Empirically Optimized Flow Cytometric Immunoassay Validates Ambient Analyte Theory

PubMed Central

Parpia, Zaheer A.; Kelso, David M.

2010-01-01

Ekins’ ambient analyte theory predicts, counter intuitively, that an immunoassay’s limit of detection can be improved by reducing the amount of capture antibody. In addition, it also anticipates that results should be insensitive to the volume of sample as well as the amount of capture antibody added. The objective of this study is to empirically validate all of the performance characteristics predicted by Ekins’ theory. Flow cytometric analysis was used to detect binding between a fluorescent ligand and capture microparticles since it can directly measure fractional occupancy, the primary response variable in ambient analyte theory. After experimentally determining ambient analyte conditions, comparisons were carried out between ambient and non-ambient assays in terms of their signal strengths, limits of detection, and their sensitivity to variations in reaction volume and number of particles. The critical number of binding sites required for an assay to be in the ambient analyte region was estimated to be 0.1VKd. As predicted, such assays exhibited superior signal/noise levels and limits of detection; and were not affected by variations in sample volume and number of binding sites. When the signal detected measures fractional occupancy, ambient analyte theory is an excellent guide to developing assays with superior performance characteristics. PMID:20152793

Automated radial basis function neural network based image classification system for diabetic retinopathy detection in retinal images

NASA Astrophysics Data System (ADS)

Anitha, J.; Vijila, C. Kezi Selva; Hemanth, D. Jude

2010-02-01

Diabetic retinopathy (DR) is a chronic eye disease for which early detection is highly essential to avoid any fatal results. Image processing of retinal images emerge as a feasible tool for this early diagnosis. Digital image processing techniques involve image classification which is a significant technique to detect the abnormality in the eye. Various automated classification systems have been developed in the recent years but most of them lack high classification accuracy. Artificial neural networks are the widely preferred artificial intelligence technique since it yields superior results in terms of classification accuracy. In this work, Radial Basis function (RBF) neural network based bi-level classification system is proposed to differentiate abnormal DR Images and normal retinal images. The results are analyzed in terms of classification accuracy, sensitivity and specificity. A comparative analysis is performed with the results of the probabilistic classifier namely Bayesian classifier to show the superior nature of neural classifier. Experimental results show promising results for the neural classifier in terms of the performance measures.

A new multi-spectral feature level image fusion method for human interpretation

NASA Astrophysics Data System (ADS)

Leviner, Marom; Maltz, Masha

2009-03-01

Various different methods to perform multi-spectral image fusion have been suggested, mostly on the pixel level. However, the jury is still out on the benefits of a fused image compared to its source images. We present here a new multi-spectral image fusion method, multi-spectral segmentation fusion (MSSF), which uses a feature level processing paradigm. To test our method, we compared human observer performance in a three-task experiment using MSSF against two established methods: averaging and principle components analysis (PCA), and against its two source bands, visible and infrared. The three tasks that we studied were: (1) simple target detection, (2) spatial orientation, and (3) camouflaged target detection. MSSF proved superior to the other fusion methods in all three tests; MSSF also outperformed the source images in the spatial orientation and camouflaged target detection tasks. Based on these findings, current speculation about the circumstances in which multi-spectral image fusion in general and specific fusion methods in particular would be superior to using the original image sources can be further addressed.

[Significance of Septin9 gene methylation detection of plasma circulation DNA in colorectal cancer screening].

PubMed

Kang, Qian; Jin, Peng; Yang, Lang; Wang, Xin; An, Hejuan; Liu, Lili; Li, Na; Sheng, Jianqiu

2014-12-30

To explore the role of detecting the methylation status of gene Septin9 (SEPT9) in plasma for colorectal cancer screening in Chinese population. Patients were collected from Beijing Military General Hospital since September 2013 to February 2014. The performance of SEPT9 assay was validated in a single-blind study of 80 cases with colonoscopy and pathologically verified colorectal cancer and 52 normal controls. The detection of Septin9 gene methylation in peripheral blood was performed by fluorescence quantitative polymerase chain reaction (PCR). And immunoassay fecal occult blood test was conducted to compare the superiority of methylated Septin9 for screening colorectal cancer. The Septin9 assay successfully identified 75.0% (95%CI:64.7%-83.6%) of cancers at a specificity of 98.1% (95%CI:90.9%-99.9%). And it was superior to fecal occult blood screening for colorectal cancer (sensitivity 79.5% vs 53.8%, P < 0.05). Determination of SEPT9 methylation status is an innovative non-invasive plasma screening test for colorectal cancer.

A systematic review and meta-analysis of diagnostic test of MRA versus MRI for detection superior labrum anterior to posterior lesions type II-VII.

PubMed

Arirachakaran, Alisara; Boonard, Manusak; Chaijenkij, Kornkit; Pituckanotai, Kwanchai; Prommahachai, Akom; Kongtharvonskul, Jatupon

2017-02-01

To determine the diagnostic performance of magnetic resonance arthrography (MRA) and magnetic resonance imaging (MRI) in superior labrum anterior to posterior lesions (type II-VII) of the shoulder. PubMed and Scopus search engines, an electronic search of articles was performed from inception to February 19, 2016. Diagnostic performance of index tests was compared by the summary area under receiver operator characteristic curve (AUROC). In all, 117 of 493 studies were eligible and 32 studies (2,013 shoulders) and 11 studies (1,498 shoulders) were evaluated with MRA and MRI. The summary sensitivity, specificity, likelihood ratio (positive and negative) and AUROC were 0.87 (95 % confidence interval, CI: 0.82, 0.91), 0.92 (95 %CI: 0.85, 0.95), 10.28 (95 %CI: 5.84, 18.08), 0.14 (95 %CI: 0.10, 0.20) and 0.94 (95 %CI: 0.92, 0.96) respectively for MRA, and 0.76 (95 %CI: 0.61, 0.86), 0.87 (95 %CI: 0.71, 0.95), 5.89 (95 %CI: 2.5, 13.86), 0.28 (95 %CI: 0.17, 0.47) and 0.94 (95 %CI: 0.92, 0.96) respectively for MRI. The diagnostic performance of MRA was superior to MRI by both direct and indirect comparisons for the detection of SLAP lesions.

Application of the shifted excitation Raman difference spectroscopy (SERDS) to the analysis of trace amounts of methanol in red wines

NASA Astrophysics Data System (ADS)

Volodin, Boris; Dolgy, Sergei; Ban, Vladimir S.; Gracin, Davor; Juraić, Krunoslav; Gracin, Leo

2014-03-01

Shifted Excitation Raman Difference Spectroscopy (SERDS) has proven an effective method for performing Raman analysis of fluorescent samples. This technique allows achieving excellent signal to noise performance with shorter excitation wavelengths, thus taking full advantage of the superior signal strength afforded by shorter excitation wavelengths and the superior performance, also combined with lower cost, delivered by silicon CCDs. The technique is enabled by use of two closely space fixed-wavelength laser diode sources stabilized with the Volume Bragg gratings (VBGs). A side by side comparison reveals that SERDS technique delivers superior signal to noise ratio and better detection limits in most situations, even when a longer excitation wavelength is employed for the purpose of elimination of the fluorescence. We have applied the SERDS technique to the quantitative analysis of the presence of trace amounts of methanol in red wines, which is an important task in quality control operations within wine industry and is currently difficult to perform in the field. So far conventional Raman spectroscopy analysis of red wines has been impractical due to the high degree of fluorescence.

Spoiled gradient recalled acquisition in the steady state technique is superior to conventional postcontrast spin echo technique for magnetic resonance imaging detection of adrenocorticotropin-secreting pituitary tumors.

PubMed

Patronas, Nicholas; Bulakbasi, Nail; Stratakis, Constantine A; Lafferty, Antony; Oldfield, Edward H; Doppman, John; Nieman, Lynnette K

2003-04-01

Recent studies show that the standard T1-weighted spin echo (SE) technique for magnetic resonance imaging (MRI) fails to identify 40% of corticotrope adenomas. We hypothesized that the superior soft tissue contrast and thinner sections obtained with spoiled gradient recalled acquisition in the steady state (SPGR) would improve tumor detection. We compared the performance of SE and SPGR MRI in 50 patients (age, 7-67 yr) with surgically confirmed corticotrope adenoma. Coronal SE and SPGR MR images were obtained before and after administration of gadolinium contrast, using a 1.5 T scanner. SE scans were obtained over 5.1 min (12-cm field of view; interleaved sections, 3 mm). SPGR scans were obtained over 3.45 min (12- or 18-cm field of view, contiguous 1- or 2-mm slices). The MRI interpretations of two radiologists were compared with findings at surgical resection. Compared with SE for detection of tumor, SPGR had superior sensitivity (80%; confidence interval, 68-91; vs. 49%; confidence interval, 34-63%), but a higher false positive rate (2% vs. 4%). We recommend the addition of SPGR to SE sequences using pituitary-specific technical parameters to improve the MRI detection of ACTH-secreting pituitary tumors.

Synovial fluid multiplex PCR is superior to culture for detection of low-virulent pathogens causing periprosthetic joint infection.

PubMed

Morgenstern, Christian; Cabric, Sabrina; Perka, Carsten; Trampuz, Andrej; Renz, Nora

2018-02-01

Analysis of joint aspirate is the standard preoperative investigation for diagnosis of periprosthetic joint infection (PJI). We compared the diagnostic performance of culture and multiplex polymerase chain reaction (PCR) of synovial fluid for diagnosis of PJI. Patients in whom aspiration of the prosthetic hip or knee joint was performed before revision arthroplasty were prospectively included. The performance of synovial fluid culture and multiplex PCR was compared by McNemar's chi-squared test. A total of 142 patients were included, 82 with knee and 60 with hip prosthesis. PJI was diagnosed in 77 patients (54%) and aseptic failure in 65 patients (46%). The sensitivity of synovial fluid culture and PCR was 52% and 60%, respectively, showing concordant results in 116 patients (82%). In patients with PJI, PCR missed 6 high-virulent pathogens (S. aureus, streptococci, E. faecalis, E. coli) which grew in synovial fluid culture, whereas synovial fluid culture missed 12 pathogens detected by multiplex PCR, predominantly low-virulent pathogens (Cutibacterium acnes and coagulase-negative staphylococci). In patients with aseptic failure, PCR detected 6 low-virulent organisms (predominantly C. acnes). While the overall performance of synovial fluid PCR was comparable to culture, PCR was superior for detection of low-virulent bacteria such as Cutibacterium spp. and coagulase-negative staphylococci. In addition, synovial fluid culture required several days for growth, whereas multiplex PCR provided results within 5hours in an automated manner. Copyright © 2017 Elsevier Inc. All rights reserved.

Searching Remote Homology with Spectral Clustering with Symmetry in Neighborhood Cluster Kernels

PubMed Central

Maulik, Ujjwal; Sarkar, Anasua

2013-01-01

Remote homology detection among proteins utilizing only the unlabelled sequences is a central problem in comparative genomics. The existing cluster kernel methods based on neighborhoods and profiles and the Markov clustering algorithms are currently the most popular methods for protein family recognition. The deviation from random walks with inflation or dependency on hard threshold in similarity measure in those methods requires an enhancement for homology detection among multi-domain proteins. We propose to combine spectral clustering with neighborhood kernels in Markov similarity for enhancing sensitivity in detecting homology independent of “recent” paralogs. The spectral clustering approach with new combined local alignment kernels more effectively exploits the unsupervised protein sequences globally reducing inter-cluster walks. When combined with the corrections based on modified symmetry based proximity norm deemphasizing outliers, the technique proposed in this article outperforms other state-of-the-art cluster kernels among all twelve implemented kernels. The comparison with the state-of-the-art string and mismatch kernels also show the superior performance scores provided by the proposed kernels. Similar performance improvement also is found over an existing large dataset. Therefore the proposed spectral clustering framework over combined local alignment kernels with modified symmetry based correction achieves superior performance for unsupervised remote homolog detection even in multi-domain and promiscuous domain proteins from Genolevures database families with better biological relevance. Source code available upon request. Contact: sarkar@labri.fr. PMID:23457439

Searching remote homology with spectral clustering with symmetry in neighborhood cluster kernels.

PubMed

Maulik, Ujjwal; Sarkar, Anasua

2013-01-01

Remote homology detection among proteins utilizing only the unlabelled sequences is a central problem in comparative genomics. The existing cluster kernel methods based on neighborhoods and profiles and the Markov clustering algorithms are currently the most popular methods for protein family recognition. The deviation from random walks with inflation or dependency on hard threshold in similarity measure in those methods requires an enhancement for homology detection among multi-domain proteins. We propose to combine spectral clustering with neighborhood kernels in Markov similarity for enhancing sensitivity in detecting homology independent of "recent" paralogs. The spectral clustering approach with new combined local alignment kernels more effectively exploits the unsupervised protein sequences globally reducing inter-cluster walks. When combined with the corrections based on modified symmetry based proximity norm deemphasizing outliers, the technique proposed in this article outperforms other state-of-the-art cluster kernels among all twelve implemented kernels. The comparison with the state-of-the-art string and mismatch kernels also show the superior performance scores provided by the proposed kernels. Similar performance improvement also is found over an existing large dataset. Therefore the proposed spectral clustering framework over combined local alignment kernels with modified symmetry based correction achieves superior performance for unsupervised remote homolog detection even in multi-domain and promiscuous domain proteins from Genolevures database families with better biological relevance. Source code available upon request. sarkar@labri.fr.

Moving target detection for frequency agility radar by sparse reconstruction

NASA Astrophysics Data System (ADS)

Quan, Yinghui; Li, YaChao; Wu, Yaojun; Ran, Lei; Xing, Mengdao; Liu, Mengqi

2016-09-01

Frequency agility radar, with randomly varied carrier frequency from pulse to pulse, exhibits superior performance compared to the conventional fixed carrier frequency pulse-Doppler radar against the electromagnetic interference. A novel moving target detection (MTD) method is proposed for the estimation of the target's velocity of frequency agility radar based on pulses within a coherent processing interval by using sparse reconstruction. Hardware implementation of orthogonal matching pursuit algorithm is executed on Xilinx Virtex-7 Field Programmable Gata Array (FPGA) to perform sparse optimization. Finally, a series of experiments are performed to evaluate the performance of proposed MTD method for frequency agility radar systems.

Moving target detection for frequency agility radar by sparse reconstruction.

PubMed

Quan, Yinghui; Li, YaChao; Wu, Yaojun; Ran, Lei; Xing, Mengdao; Liu, Mengqi

2016-09-01

Frequency agility radar, with randomly varied carrier frequency from pulse to pulse, exhibits superior performance compared to the conventional fixed carrier frequency pulse-Doppler radar against the electromagnetic interference. A novel moving target detection (MTD) method is proposed for the estimation of the target's velocity of frequency agility radar based on pulses within a coherent processing interval by using sparse reconstruction. Hardware implementation of orthogonal matching pursuit algorithm is executed on Xilinx Virtex-7 Field Programmable Gata Array (FPGA) to perform sparse optimization. Finally, a series of experiments are performed to evaluate the performance of proposed MTD method for frequency agility radar systems.

Graphene-carbon nanotube composite aerogel for selective detection of uric acid

NASA Astrophysics Data System (ADS)

Zhang, Feifei; Tang, Jie; Wang, Zonghua; Qin, Lu-Chang

2013-12-01

Graphene and single-walled carbon nanotube (SWNT) composite aerogel has been prepared by hydrothermal synthesis. The restacking of graphene is effectively reduced by SWNTs inserted in between graphene layers in order to make available more active sites and reactive surface area. Electrochemical experiments show that the graphene-SWNT composite electrode has superior catalytic performance in selective detection of uric acid (UA).

Automatic target detection using binary template matching

NASA Astrophysics Data System (ADS)

Jun, Dong-San; Sun, Sun-Gu; Park, HyunWook

2005-03-01

This paper presents a new automatic target detection (ATD) algorithm to detect targets such as battle tanks and armored personal carriers in ground-to-ground scenarios. Whereas most ATD algorithms were developed for forward-looking infrared (FLIR) images, we have developed an ATD algorithm for charge-coupled device (CCD) images, which have superior quality to FLIR images in daylight. The proposed algorithm uses fast binary template matching with an adaptive binarization, which is robust to various light conditions in CCD images and saves computation time. Experimental results show that the proposed method has good detection performance.

Evaluation of Ca3Co2O6 as cathode material for high-performance solid-oxide fuel cell

PubMed Central

Wei, Tao; Huang, Yun-Hui; Zeng, Rui; Yuan, Li-Xia; Hu, Xian-Luo; Zhang, Wu-Xing; Jiang, Long; Yang, Jun-You; Zhang, Zhao-Liang

2013-01-01

A cobalt-based thermoelectric compound Ca3Co2O6 (CCO) has been developed as new cathode material with superior performance for intermediate-temperature (IT) solid-oxide fuel cell (SOFC). Systematic evaluation has been carried out. Measurement of thermal expansion coefficient (TEC), thermal-stress (σ) and interfacial shearing stress (τ) with the electrolyte show that CCO matches well with several commonly-used IT electrolytes. Maximum power density as high as 1.47 W cm−2 is attained at 800°C, and an additional thermoelectric voltage of 11.7 mV is detected. The superior electrochemical performance, thermoelectric effect, and comparable thermal and mechanical behaviors with the electrolytes make CCO to be a promising cathode material for SOFC. PMID:23350032

High Hydrogen Content Graphene Hydride Compounds & High Cross-­ Section Cladding Coatings for Fast Neutron Detection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chandrashekhar, MVS

The objective is to develop and implement a superior low-cost, large area (potentially >32in), easily deployable, close proximity, harsh environment innovative neutron sensor needed for next generation fuel cycle monitoring. We will exploit recent breakthroughs at the PI’s lab on the electrochemistry of epitaxial graphene (EG) formed on commercial SiC wafers, a transformative nanomaterial system with superior radiation detection and durability properties to develop a new paradigm in detection for fast neutrons, a by-product of fission reactors. There are currently few effective detection/monitoring schemes, especially solid-state ones at present. This is essential for monitoring and control of future fuel cyclesmore » to make them more efficient and reliable. By exploiting these novel materials, as well as innovative hybrid SiC/EG/Cladding device architectures conceived by the team, will develop low-cost, high performance solutions to fast-neutron detection. Finally, we will also explore 3-terminal device implementations for neutron detectors with built-in electronic gain to further shrink these devices and improve their sensitivity.« less

Can spectro-temporal complexity explain the autistic pattern of performance on auditory tasks?

PubMed

Samson, Fabienne; Mottron, Laurent; Jemel, Boutheina; Belin, Pascal; Ciocca, Valter

2006-01-01

To test the hypothesis that level of neural complexity explain the relative level of performance and brain activity in autistic individuals, available behavioural, ERP and imaging findings related to the perception of increasingly complex auditory material under various processing tasks in autism were reviewed. Tasks involving simple material (pure tones) and/or low-level operations (detection, labelling, chord disembedding, detection of pitch changes) show a superior level of performance and shorter ERP latencies. In contrast, tasks involving spectrally- and temporally-dynamic material and/or complex operations (evaluation, attention) are poorly performed by autistics, or generate inferior ERP activity or brain activation. Neural complexity required to perform auditory tasks may therefore explain pattern of performance and activation of autistic individuals during auditory tasks.

A new full-field digital mammography system with and without the use of an advanced post-processing algorithm: comparison of image quality and diagnostic performance.

PubMed

Ahn, Hye Shin; Kim, Sun Mi; Jang, Mijung; Yun, Bo La; Kim, Bohyoung; Ko, Eun Sook; Han, Boo-Kyung; Chang, Jung Min; Yi, Ann; Cho, Nariya; Moon, Woo Kyung; Choi, Hye Young

2014-01-01

To compare new full-field digital mammography (FFDM) with and without use of an advanced post-processing algorithm to improve image quality, lesion detection, diagnostic performance, and priority rank. During a 22-month period, we prospectively enrolled 100 cases of specimen FFDM mammography (Brestige®), which was performed alone or in combination with a post-processing algorithm developed by the manufacturer: group A (SMA), specimen mammography without application of "Mammogram enhancement ver. 2.0"; group B (SMB), specimen mammography with application of "Mammogram enhancement ver. 2.0". Two sets of specimen mammographies were randomly reviewed by five experienced radiologists. Image quality, lesion detection, diagnostic performance, and priority rank with regard to image preference were evaluated. Three aspects of image quality (overall quality, contrast, and noise) of the SMB were significantly superior to those of SMA (p < 0.05). SMB was significantly superior to SMA for visualizing calcifications (p < 0.05). Diagnostic performance, as evaluated by cancer score, was similar between SMA and SMB. SMB was preferred to SMA by four of the five reviewers. The post-processing algorithm may improve image quality with better image preference in FFDM than without use of the software.

Dual-energy bone removal computed tomography (BRCT): preliminary report of efficacy of acute intracranial hemorrhage detection.

PubMed

Naruto, Norihito; Tannai, Hidenori; Nishikawa, Kazuma; Yamagishi, Kentaro; Hashimoto, Masahiko; Kawabe, Hideto; Kamisaki, Yuichi; Sumiya, Hisashi; Kuroda, Satoshi; Noguchi, Kyo

2018-02-01

One of the major applications of dual-energy computed tomography (DECT) is automated bone removal (BR). We hypothesized that the visualization of acute intracranial hemorrhage could be improved on BRCT by removing bone as it has the highest density tissue in the head. This preliminary study evaluated the efficacy of a DE BR algorithm for the head CT of trauma patients. Sixteen patients with acute intracranial hemorrhage within 1 day after head trauma were enrolled in this study. All CT examinations were performed on a dual-source dual-energy CT scanner. BRCT images were generated using the Bone Removal Application. Simulated standard CT and BRCT images were visually reviewed in terms of detectability (presence or absence) of acute hemorrhagic lesions. DECT depicted 28 epidural/subdural hemorrhages, 17 contusional hemorrhages, and 7 subarachnoid hemorrhages. In detecting epidural/subdural hemorrhage, BRCT [28/28 (100%)] was significantly superior to simulated standard CT [17/28 (61%)] (p = .001). In detecting contusional hemorrhage, BRCT [17/17 (100%)] was also significantly superior to simulated standard CT [11/17 (65%)] (p = .0092). BRCT was superior to simulated standard CT in detecting acute intracranial hemorrhage. BRCT could improve the detection of small intracranial hemorrhages, particularly those adjacent to bone, by removing bone that can interfere with the visualization of small acute hemorrhage. In an emergency such as head trauma, BRCT can be used as support imaging in combination with simulated standard CT and bone scale CT, although BRCT cannot replace a simulated standard CT.

Principles in sampling design, lessons, and recommendations from a multi-year, multi-port surveillance program in Lake Superior

EPA Science Inventory

We evaluated a pilot aquatic invasive species (AIS) early detection monitoring program in Lake Superior that was designed to detect newly-introduced fishes. We established survey protocols for three major ports (Duluth-Superior, Sault Ste. Marie, Thunder Bay), and designed an ada...

Detection of subjects and brain regions related to Alzheimer's disease using 3D MRI scans based on eigenbrain and machine learning

PubMed Central

Zhang, Yudong; Dong, Zhengchao; Phillips, Preetha; Wang, Shuihua; Ji, Genlin; Yang, Jiquan; Yuan, Ti-Fei

2015-01-01

Purpose: Early diagnosis or detection of Alzheimer's disease (AD) from the normal elder control (NC) is very important. However, the computer-aided diagnosis (CAD) was not widely used, and the classification performance did not reach the standard of practical use. We proposed a novel CAD system for MR brain images based on eigenbrains and machine learning with two goals: accurate detection of both AD subjects and AD-related brain regions. Method: First, we used maximum inter-class variance (ICV) to select key slices from 3D volumetric data. Second, we generated an eigenbrain set for each subject. Third, the most important eigenbrain (MIE) was obtained by Welch's t-test (WTT). Finally, kernel support-vector-machines with different kernels that were trained by particle swarm optimization, were used to make an accurate prediction of AD subjects. Coefficients of MIE with values higher than 0.98 quantile were highlighted to obtain the discriminant regions that distinguish AD from NC. Results: The experiments showed that the proposed method can predict AD subjects with a competitive performance with existing methods, especially the accuracy of the polynomial kernel (92.36 ± 0.94) was better than the linear kernel of 91.47 ± 1.02 and the radial basis function (RBF) kernel of 86.71 ± 1.93. The proposed eigenbrain-based CAD system detected 30 AD-related brain regions (Anterior Cingulate, Caudate Nucleus, Cerebellum, Cingulate Gyrus, Claustrum, Inferior Frontal Gyrus, Inferior Parietal Lobule, Insula, Lateral Ventricle, Lentiform Nucleus, Lingual Gyrus, Medial Frontal Gyrus, Middle Frontal Gyrus, Middle Occipital Gyrus, Middle Temporal Gyrus, Paracentral Lobule, Parahippocampal Gyrus, Postcentral Gyrus, Posterial Cingulate, Precentral Gyrus, Precuneus, Subcallosal Gyrus, Sub-Gyral, Superior Frontal Gyrus, Superior Parietal Lobule, Superior Temporal Gyrus, Supramarginal Gyrus, Thalamus, Transverse Temporal Gyrus, and Uncus). The results were coherent with existing literatures. Conclusion: The eigenbrain method was effective in AD subject prediction and discriminant brain-region detection in MRI scanning. PMID:26082713

Telemetry Tests Of The Advanced Receiver II

NASA Technical Reports Server (NTRS)

Hinedi, Sami M.; Bevan, Roland P.; Marina, Miguel

1993-01-01

Report describes telemetry tests of Advanced Receiver II (ARX-II): digital radio receiving subsystem operating on intermediate-frequency output of another receiving subsystem called "multimission receiver" (MMR), detecting carrier, subcarrier, and data-symbol signals transmitted by spacecraft, and extracts Doppler information from signals. Analysis of data shows performance of MMR/ARX-II system comparable and sometimes superior to performances of Blk-III/BPA and Blk-III/SDA/SSA systems.

Performance of the CLSI Carba NP and the Rosco Carb Screen Assays Using North American Carbapenemase-Producing Enterobacteriaceae and Pseudomonas aeruginosa Isolates

PubMed Central

Gallagher, Lauren C.; Roundtree, Sylvester S.; Lancaster, Diana P.; Rudin, Susan D.; Bard, Jennifer Dien; Roberts, Amity L.; Marshall, Steven H.; Bonomo, Robert A.

2015-01-01

This study compared the performance of the Carba NP assay, published by the Clinical and Laboratory Standards Institute, and the Rosco Rapid Carb Screen kit. Carba NP had superior sensitivity, but both assays required an increased inoculum to detect carbapenemase production in isolates with blaNDM, blaIMP, and blaOXA-48. PMID:26269624

Spoof Detection for Finger-Vein Recognition System Using NIR Camera.

PubMed

Nguyen, Dat Tien; Yoon, Hyo Sik; Pham, Tuyen Danh; Park, Kang Ryoung

2017-10-01

Finger-vein recognition, a new and advanced biometrics recognition method, is attracting the attention of researchers because of its advantages such as high recognition performance and lesser likelihood of theft and inaccuracies occurring on account of skin condition defects. However, as reported by previous researchers, it is possible to attack a finger-vein recognition system by using presentation attack (fake) finger-vein images. As a result, spoof detection, named as presentation attack detection (PAD), is necessary in such recognition systems. Previous attempts to establish PAD methods primarily focused on designing feature extractors by hand (handcrafted feature extractor) based on the observations of the researchers about the difference between real (live) and presentation attack finger-vein images. Therefore, the detection performance was limited. Recently, the deep learning framework has been successfully applied in computer vision and delivered superior results compared to traditional handcrafted methods on various computer vision applications such as image-based face recognition, gender recognition and image classification. In this paper, we propose a PAD method for near-infrared (NIR) camera-based finger-vein recognition system using convolutional neural network (CNN) to enhance the detection ability of previous handcrafted methods. Using the CNN method, we can derive a more suitable feature extractor for PAD than the other handcrafted methods using a training procedure. We further process the extracted image features to enhance the presentation attack finger-vein image detection ability of the CNN method using principal component analysis method (PCA) for dimensionality reduction of feature space and support vector machine (SVM) for classification. Through extensive experimental results, we confirm that our proposed method is adequate for presentation attack finger-vein image detection and it can deliver superior detection results compared to CNN-based methods and other previous handcrafted methods.

Spoof Detection for Finger-Vein Recognition System Using NIR Camera

PubMed Central

Nguyen, Dat Tien; Yoon, Hyo Sik; Pham, Tuyen Danh; Park, Kang Ryoung

2017-01-01

Finger-vein recognition, a new and advanced biometrics recognition method, is attracting the attention of researchers because of its advantages such as high recognition performance and lesser likelihood of theft and inaccuracies occurring on account of skin condition defects. However, as reported by previous researchers, it is possible to attack a finger-vein recognition system by using presentation attack (fake) finger-vein images. As a result, spoof detection, named as presentation attack detection (PAD), is necessary in such recognition systems. Previous attempts to establish PAD methods primarily focused on designing feature extractors by hand (handcrafted feature extractor) based on the observations of the researchers about the difference between real (live) and presentation attack finger-vein images. Therefore, the detection performance was limited. Recently, the deep learning framework has been successfully applied in computer vision and delivered superior results compared to traditional handcrafted methods on various computer vision applications such as image-based face recognition, gender recognition and image classification. In this paper, we propose a PAD method for near-infrared (NIR) camera-based finger-vein recognition system using convolutional neural network (CNN) to enhance the detection ability of previous handcrafted methods. Using the CNN method, we can derive a more suitable feature extractor for PAD than the other handcrafted methods using a training procedure. We further process the extracted image features to enhance the presentation attack finger-vein image detection ability of the CNN method using principal component analysis method (PCA) for dimensionality reduction of feature space and support vector machine (SVM) for classification. Through extensive experimental results, we confirm that our proposed method is adequate for presentation attack finger-vein image detection and it can deliver superior detection results compared to CNN-based methods and other previous handcrafted methods. PMID:28974031

Sampling design for early detection of aquatic invasive species in Great Lakes ports

EPA Science Inventory

We evaluated a pilot adaptive monitoring program for aquatic invasive species (AIS) early detection in Lake Superior. The monitoring program is designed to detect newly-introduced fishes, and encompasses the lake’s three major ports (Duluth-Superior, Sault Ste. Marie, Thund...

Sampling design for aquatic invasive species early detection in Great Lakes ports

EPA Science Inventory

From 2006-2012, we evaluated a pilot aquatic invasive species (AIS) early detection monitoring program in Lake Superior that was designed to detect newly introduced fishes. We established survey protocols for three major ports (Duluth-Superior, Sault Ste. Marie, Thunder Bay) and ...

Detection of Alzheimer's Disease by Three-Dimensional Displacement Field Estimation in Structural Magnetic Resonance Imaging.

PubMed

Wang, Shuihua; Zhang, Yudong; Liu, Ge; Phillips, Preetha; Yuan, Ti-Fei

2016-01-01

Within the past decade, computer scientists have developed many methods using computer vision and machine learning techniques to detect Alzheimer's disease (AD) in its early stages. However, some of these methods are unable to achieve excellent detection accuracy, and several other methods are unable to locate AD-related regions. Hence, our goal was to develop a novel AD brain detection method. In this study, our method was based on the three-dimensional (3D) displacement-field (DF) estimation between subjects in the healthy elder control group and AD group. The 3D-DF was treated with AD-related features. The three feature selection measures were used in the Bhattacharyya distance, Student's t-test, and Welch's t-test (WTT). Two non-parallel support vector machines, i.e., generalized eigenvalue proximal support vector machine and twin support vector machine (TSVM), were then used for classification. A 50 × 10-fold cross validation was implemented for statistical analysis. The results showed that "3D-DF+WTT+TSVM" achieved the best performance, with an accuracy of 93.05 ± 2.18, a sensitivity of 92.57 ± 3.80, a specificity of 93.18 ± 3.35, and a precision of 79.51 ± 2.86. This method also exceled in 13 state-of-the-art approaches. Additionally, we were able to detect 17 regions related to AD by using the pure computer-vision technique. These regions include sub-gyral, inferior parietal lobule, precuneus, angular gyrus, lingual gyrus, supramarginal gyrus, postcentral gyrus, third ventricle, superior parietal lobule, thalamus, middle temporal gyrus, precentral gyrus, superior temporal gyrus, superior occipital gyrus, cingulate gyrus, culmen, and insula. These regions were reported in recent publications. The 3D-DF is effective in AD subject and related region detection.

[Transthoracic and transesophageal echocardiography in the pre- and postoperative assessment of interatrial communication].

PubMed

San Román, J A; Vilacosta, I; Zamorano, J; Castillo, J A; Rollán, M J; Villanueva, M A; Almería, C; Sánchez-Harguindey, L

1993-12-01

Transthoracic echocardiography is the most useful noninvasive method to diagnose atrial septal defect. It is suggested by some authors that transesophageal echocardiography is more accurate than transthoracic echocardiography in this setting. Our aim was to compare the usefulness of both techniques in: 1) diagnosing atrial septal defect, 2) detecting associated anomalies and 3) postoperative assessment. Pre and postoperative transthoracic and transesophageal echocardiography were performed in 27 patients in whom diagnosis of atrial septal defect was confirmed at surgery. Transthoracic echocardiography demonstrated the defect in 20 patients (74%) (8 ostium primum, 10 ostium secundum and 2 sinus venosus). The 27 patients (100%) were correctly diagnosed by transesophageal echocardiography (8 ostium primum, 12 ostium secundum and 7 sinus venosus). Defect size determined by transthoracic echocardiography had a poor correlation with the surgical measurement (r = 0.34). A good correlation was obtained when transesophageal versus surgical defect size measurements were compared (r = 0.85; p < 0.05). Transesophageal echocardiography was superior in detecting associated anomalies (5 patients with anomalous partial pulmonary venous drainage, 3 persistence of left superior vena cava and 1 atrial septal aneurysm). Moreover, this technique better determined residual atrial septal defect, and detected a postsurgical inferior vena cava connection to the left atrium. Transesophageal echocardiography is superior to transthoracic echocardiography in diagnosing atrial septal defect sinus venosus type, detecting associated anomalies and postoperative assessment. Transthoracic echocardiography is diagnostic in the majority of patients with atrial septal defect ostium primum and ostium secundum types.

Implementing a Parallel Image Edge Detection Algorithm Based on the Otsu-Canny Operator on the Hadoop Platform.

PubMed

Cao, Jianfang; Chen, Lichao; Wang, Min; Tian, Yun

2018-01-01

The Canny operator is widely used to detect edges in images. However, as the size of the image dataset increases, the edge detection performance of the Canny operator decreases and its runtime becomes excessive. To improve the runtime and edge detection performance of the Canny operator, in this paper, we propose a parallel design and implementation for an Otsu-optimized Canny operator using a MapReduce parallel programming model that runs on the Hadoop platform. The Otsu algorithm is used to optimize the Canny operator's dual threshold and improve the edge detection performance, while the MapReduce parallel programming model facilitates parallel processing for the Canny operator to solve the processing speed and communication cost problems that occur when the Canny edge detection algorithm is applied to big data. For the experiments, we constructed datasets of different scales from the Pascal VOC2012 image database. The proposed parallel Otsu-Canny edge detection algorithm performs better than other traditional edge detection algorithms. The parallel approach reduced the running time by approximately 67.2% on a Hadoop cluster architecture consisting of 5 nodes with a dataset of 60,000 images. Overall, our approach system speeds up the system by approximately 3.4 times when processing large-scale datasets, which demonstrates the obvious superiority of our method. The proposed algorithm in this study demonstrates both better edge detection performance and improved time performance.

The role of Fluorine-18-Fluorodeoxyglucose positron emission tomography in staging and restaging of patients with osteosarcoma.

PubMed

Quartuccio, Natale; Treglia, Giorgio; Salsano, Marco; Mattoli, Maria Vittoria; Muoio, Barbara; Piccardo, Arnoldo; Lopci, Egesta; Cistaro, Angelina

2013-06-01

The objective of this study is to systematically review the role of positron emission tomography (PET) and PET/computed tomography (PET/CT) with Fluorine-18-Fluorodeoxyglucose (FDG) in patients with osteosarcoma (OS). A comprehensive literature search of published studies through October 10(th), 2012 in PubMed/MEDLINE, Embase and Scopus databases regarding whole-body FDG-PET and FDG-PET/CT in patients with OS was performed. We identified 13 studies including 289 patients with OS. With regard to the staging and restaging of OS, the diagnostic performance of FDG-PET and PET/CT seem to be high; FDG-PET and PET/CT seem to be superior to bone scintigraphy and conventional imaging methods in detecting bone metastases; conversely, spiral CT seems to be superior to FDG-PET in detecting pulmonary metastases from OS. Metabolic imaging may provide additional information in the evaluation of OS patients. The combination of FDG-PET or FDG-PET/CT with conventional imaging methods seems to be a valuable tool in the staging and restaging of OS and may have a relevant impact on the treatment planning.

Neuroanatomical correlates of biological motion detection.

PubMed

Gilaie-Dotan, Sharon; Kanai, Ryota; Bahrami, Bahador; Rees, Geraint; Saygin, Ayse P

2013-02-01

Biological motion detection is both commonplace and important, but there is great inter-individual variability in this ability, the neural basis of which is currently unknown. Here we examined whether the behavioral variability in biological motion detection is reflected in brain anatomy. Perceptual thresholds for detection of biological motion and control conditions (non-biological object motion detection and motion coherence) were determined in a group of healthy human adults (n=31) together with structural magnetic resonance images of the brain. Voxel based morphometry analyzes revealed that gray matter volumes of left posterior superior temporal sulcus (pSTS) and left ventral premotor cortex (vPMC) significantly predicted individual differences in biological motion detection, but showed no significant relationship with performance on the control tasks. Our study reveals a neural basis associated with the inter-individual variability in biological motion detection, reliably linking the neuroanatomical structure of left pSTS and vPMC with biological motion detection performance. Copyright © 2012 Elsevier Ltd. All rights reserved.

Dual Low-Rank Pursuit: Learning Salient Features for Saliency Detection.

PubMed

Lang, Congyan; Feng, Jiashi; Feng, Songhe; Wang, Jingdong; Yan, Shuicheng

2016-06-01

Saliency detection is an important procedure for machines to understand visual world as humans do. In this paper, we consider a specific saliency detection problem of predicting human eye fixations when they freely view natural images, and propose a novel dual low-rank pursuit (DLRP) method. DLRP learns saliency-aware feature transformations by utilizing available supervision information and constructs discriminative bases for effectively detecting human fixation points under the popular low-rank and sparsity-pursuit framework. Benefiting from the embedded high-level information in the supervised learning process, DLRP is able to predict fixations accurately without performing the expensive object segmentation as in the previous works. Comprehensive experiments clearly show the superiority of the proposed DLRP method over the established state-of-the-art methods. We also empirically demonstrate that DLRP provides stronger generalization performance across different data sets and inherits the advantages of both the bottom-up- and top-down-based saliency detection methods.

High definition versus standard definition white light endoscopy for detecting dysplasia in patients with Barrett's esophagus.

PubMed

Sami, S S; Subramanian, V; Butt, W M; Bejkar, G; Coleman, J; Mannath, J; Ragunath, K

2015-01-01

High-definition endoscopy systems provide superior image resolution. The aim of this study was to assess the utility of high definition compared with standard definition endoscopy system for detecting dysplastic lesions in patients with Barrett's esophagus. A retrospective cohort study of patients with non-dysplastic Barrett's esophagus undergoing routine surveillance was performed. Data were retrieved from the central hospital electronic database. Procedures performed for non-surveillance indications, Barrett's esophagus Prague C0M1 classification with no specialized intestinal metaplasia on histology, patients diagnosed with any dysplasia or cancer on index endoscopy, and procedures using advanced imaging techniques were excluded. Logistic regression models were constructed to estimate adjusted odds ratios and 95% confidence intervals comparing outcomes with standard definition and high-definition systems. The high definition was superior to standard definition system in targeted detection of all dysplastic lesions (odds ratio 3.27, 95% confidence interval 1.27-8.40) as well as overall dysplasia detected on both random and target biopsies (odds ratio 2.36, 95% confidence interval 1.50-3.72). More non-dysplastic lesions were detected with the high-definition system (odds ratio 1.16, 95% confidence interval 1.01-1.33). There was no difference between high definition and standard definition endoscopy in the overall (random and target) high-grade dysplasia or cancers detected (odds ratio 0.93, 95% confidence interval 0.83-1.04). Trainee endoscopists, number of biopsies taken, and male sex were all significantly associated with a higher yield for dysplastic lesions. The use of the high-definition endoscopy system is associated with better targeted detection of any dysplasia during routine Barrett's esophagus surveillance. However, high-definition endoscopy cannot replace random biopsies at present time. © 2014 International Society for Diseases of the Esophagus.

Differential detection of Gaussian MSK in a mobile radio environment

NASA Technical Reports Server (NTRS)

Simon, M. K.; Wang, C. C.

1984-01-01

Minimum shift keying with Gaussian shaped transmit pulses is a strong candidate for a modulation technique that satisfies the stringent out-of-band radiated power requirements of the mobil radio application. Numerous studies and field experiments have been conducted by the Japanese on urban and suburban mobile radio channels with systems employing Gaussian minimum-shift keying (GMSK) transmission and differentially coherent reception. A comprehensive analytical treatment is presented of the performance of such systems emphasizing the important trade-offs among the various system design parameters such as transmit and receiver filter bandwidths and detection threshold level. It is shown that two-bit differential detection of GMSK is capable of offering far superior performance to the more conventional one-bit detection method both in the presence of an additive Gaussian noise background and Rician fading.

Model-Based Design of Tree WSNs for Decentralized Detection.

PubMed

Tantawy, Ashraf; Koutsoukos, Xenofon; Biswas, Gautam

2015-08-20

The classical decentralized detection problem of finding the optimal decision rules at the sensor and fusion center, as well as variants that introduce physical channel impairments have been studied extensively in the literature. The deployment of WSNs in decentralized detection applications brings new challenges to the field. Protocols for different communication layers have to be co-designed to optimize the detection performance. In this paper, we consider the communication network design problem for a tree WSN. We pursue a system-level approach where a complete model for the system is developed that captures the interactions between different layers, as well as different sensor quality measures. For network optimization, we propose a hierarchical optimization algorithm that lends itself to the tree structure, requiring only local network information. The proposed design approach shows superior performance over several contentionless and contention-based network design approaches.

Differential detection of Gaussian MSK in a mobile radio environment

NASA Astrophysics Data System (ADS)

Simon, M. K.; Wang, C. C.

1984-11-01

Minimum shift keying with Gaussian shaped transmit pulses is a strong candidate for a modulation technique that satisfies the stringent out-of-band radiated power requirements of the mobil radio application. Numerous studies and field experiments have been conducted by the Japanese on urban and suburban mobile radio channels with systems employing Gaussian minimum-shift keying (GMSK) transmission and differentially coherent reception. A comprehensive analytical treatment is presented of the performance of such systems emphasizing the important trade-offs among the various system design parameters such as transmit and receiver filter bandwidths and detection threshold level. It is shown that two-bit differential detection of GMSK is capable of offering far superior performance to the more conventional one-bit detection method both in the presence of an additive Gaussian noise background and Rician fading.

Measuring target detection performance in paradigms with high event rates.

PubMed

Bendixen, Alexandra; Andersen, Søren K

2013-05-01

Combining behavioral and neurophysiological measurements inevitably implies mutual constraints, such as when the neurophysiological measurement requires fast-paced stimulus presentation and hence the attribution of a behavioral response to a particular preceding stimulus becomes ambiguous. We develop and test a method for validly assessing behavioral detection performance in spite of this ambiguity. We examine four approaches taken in the literature to treat such situations. We analytically derive a new variant of computing the classical parameters of signal detection theory, hit and false alarm rates, adapted to fast-paced paradigms. Each of the previous approaches shows specific shortcomings (susceptibility towards response window choice, biased estimates of behavioral detection performance). Superior performance of our new approach is demonstrated for both simulated and empirical behavioral data. Further evidence is provided by reliable correspondence between behavioral performance and the N2b component as an electrophysiological indicator of target detection. The appropriateness of our approach is substantiated by both theoretical and empirical arguments. We demonstrate an easy-to-implement solution for measuring target detection performance independent of the rate of event presentation. Thus overcoming the measurement bias of previous approaches, our method will help to clarify the behavioral relevance of different measures of cortical activation. Copyright © 2012 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Low-contrast detectability in volume rendering: a phantom study on multidetector-row spiral CT data.

PubMed

Shin, Hoen-Oh; Falck, Christian V; Galanski, Michael

2004-02-01

To cope with the increasing amount of CT data, there is growing interest in direct volume-rendering techniques (VRT) as a diagnostic tool. The aim of this phantom study was to analyze the low-contrast detectability (LCD) of VRT compared with multi-planar reformations (MPR). Soft tissue lesions were simulated by spheres of different diameters (3-8 mm). The average lesion density was 15 HU compared with a background density of 35 HU. Two different CT protocols with 40 and 150 mAs were performed on a multi-detector row CT. The scanning parameters were as following: 140 kV; 2x0.5-mm slice collimation; pitch 2 (table movement per rotation/single slice collimation), and reconstruction with 0.5-mm slice thickness at 0.5-mm interval. A B30 kernel was used for reconstruction. The VRT was performed by mapping Hounsfield values to gray levels equal to a CT window (center: 60 HU; window: 370 HU ). A linear ramp was applied for the opacity transfer function varying the maximum opacity between 0.1 and 1.0. A statistical method based on the Rose model was used to calculate the detection threshold depending on lesion size and image noise. Additionally, clinical data of 2 patients with three liver lesions of different sizes and density were evaluated. In VRT, LCD was most dependent on object size. Regarding lesions larger than 5 mm, VRT is significantly superior to MPR (p<0.05) for all opacity settings. In lesions sized 3-5 mm a maximum opacity level approximately 40-50% showed a near equivalent detectability in VRT and MPR. For higher opacity levels VRT was superior to MPR. Only for 3-mm lesions MPR performed slightly better in low-contrast detectability (p<0.05). Compared with MPR, VRT shows similar performance in LCD. Due to noise suppression effects, it is suited for visualization of data with high noise content.

Sonar Recognition Training: An Investigation of Whole VS. Part and Analytic VS. Synthetic Procedures.

ERIC Educational Resources Information Center

Annett, John

An experienced person, in such tasks as sonar detection and recognition, has a considerable superiority over a machine recognition system in auditory pattern recognition. However, people require extensive exposure to auditory patterns before achieving a high level of performance. In an attempt to discover a method of training people to recognize…

Value of Egy-Score in diagnosis of significant, advanced hepatic fibrosis and cirrhosis compared to aspartate aminotransferase-to-platelet ratio index, FIB-4 and Forns' index in chronic hepatitis C virus.

PubMed

Alboraie, Mohamed; Khairy, Marwa; Elsharkawy, Marwa; Asem, Noha; Elsharkawy, Aisha; Esmat, Gamal

2015-05-01

Serum markers and developed scores are of rising importance in non-invasive diagnosis of hepatic fibrosis. Aspartate aminotransferase-to-platelet ratio index (APRI), FIB-4 and Forns' index are validated scores used for diagnosis of liver fibrosis. The Egy-Score is a newly developed score for detection of hepatic fibrosis with promising results. We aimed to assess the accuracy of the Egy-Score in the diagnosis of significant fibrosis, advanced fibrosis and cirrhosis compared to APRI, FIB-4 and Forns' in chronic hepatitis C virus (HCV) patients. A retrospective study including 100 chronic hepatitis C naïve Egyptian patients was performed. Patients were classified according to stages of fibrosis into three groups: significant fibrosis (≥ F2), advanced fibrosis (≥ F3) and cirrhosis (F4). Egy-Score, APRI, FIB-4 and Forns' index were calculated. Regression analysis and receiver-operator curves were plotted to assess the sensitivity, specificity and predictive values for the significant scores with the best cut-off for diagnosis. An Egy-Score of 3.28 or more was superior to APRI, FIB-4 and Forns' index for detecting advanced fibrosis with a sensitivity of 91% and specificity of 78%. An Egy-Score of 3.67 or more was superior to APRI, FIB-4 and Forns' index for detecting cirrhosis with a sensitivity of 82% and specificity of 87%. Forns' index was superior to Egy-Score, FIB-4 and APRI for detecting significant fibrosis. The Egy-Score is a promising, accurate, easily calculated, cost-effective score in the prediction of hepatic fibrosis in chronic HCV patients with superiority over APRI, FIB-4 and Forns' index in advanced hepatic fibrosis and cirrhosis. © 2014 The Japan Society of Hepatology.

Implementing a Parallel Image Edge Detection Algorithm Based on the Otsu-Canny Operator on the Hadoop Platform

PubMed Central

Wang, Min; Tian, Yun

2018-01-01

The Canny operator is widely used to detect edges in images. However, as the size of the image dataset increases, the edge detection performance of the Canny operator decreases and its runtime becomes excessive. To improve the runtime and edge detection performance of the Canny operator, in this paper, we propose a parallel design and implementation for an Otsu-optimized Canny operator using a MapReduce parallel programming model that runs on the Hadoop platform. The Otsu algorithm is used to optimize the Canny operator's dual threshold and improve the edge detection performance, while the MapReduce parallel programming model facilitates parallel processing for the Canny operator to solve the processing speed and communication cost problems that occur when the Canny edge detection algorithm is applied to big data. For the experiments, we constructed datasets of different scales from the Pascal VOC2012 image database. The proposed parallel Otsu-Canny edge detection algorithm performs better than other traditional edge detection algorithms. The parallel approach reduced the running time by approximately 67.2% on a Hadoop cluster architecture consisting of 5 nodes with a dataset of 60,000 images. Overall, our approach system speeds up the system by approximately 3.4 times when processing large-scale datasets, which demonstrates the obvious superiority of our method. The proposed algorithm in this study demonstrates both better edge detection performance and improved time performance. PMID:29861711

3D-nanostructured Au electrodes for the event-specific detection of MON810 transgenic maize.

PubMed

Fátima Barroso, M; Freitas, Maria; Oliveira, M Beatriz P P; de-Los-Santos-Álvarez, Noemí; Lobo-Castañón, María Jesús; Delerue-Matos, Cristina

2015-03-01

In the present work, the development of a genosensor for the event-specific detection of MON810 transgenic maize is proposed. Taking advantage of nanostructuration, a cost-effective three dimensional electrode was fabricated and a ternary monolayer containing a dithiol, a monothiol and the thiolated capture probe was optimized to minimize the unspecific signals. A sandwich format assay was selected as a way of precluding inefficient hybridization associated with stable secondary target structures. A comparison between the analytical performance of the Au nanostructured electrodes and commercially available screen-printed electrodes highlighted the superior performance of the nanostructured ones. Finally, the genosensor was effectively applied to detect the transgenic sequence in real samples, showing its potential for future quantitative analysis. Copyright © 2014 Elsevier B.V. All rights reserved.

High-Performance Sensors Based on Resistance Fluctuations of Single-Layer-Graphene Transistors.

PubMed

Amin, Kazi Rafsanjani; Bid, Aveek

2015-09-09

One of the most interesting predicted applications of graphene-monolayer-based devices is as high-quality sensors. In this article, we show, through systematic experiments, a chemical vapor sensor based on the measurement of low-frequency resistance fluctuations of single-layer-graphene field-effect-transistor devices. The sensor has extremely high sensitivity, very high specificity, high fidelity, and fast response times. The performance of the device using this scheme of measurement (which uses resistance fluctuations as the detection parameter) is more than 2 orders of magnitude better than a detection scheme in which changes in the average value of the resistance is monitored. We propose a number-density-fluctuation-based model to explain the superior characteristics of a noise-measurement-based detection scheme presented in this article.

Distributed learning automata-based algorithm for community detection in complex networks

NASA Astrophysics Data System (ADS)

Khomami, Mohammad Mehdi Daliri; Rezvanian, Alireza; Meybodi, Mohammad Reza

2016-03-01

Community structure is an important and universal topological property of many complex networks such as social and information networks. The detection of communities of a network is a significant technique for understanding the structure and function of networks. In this paper, we propose an algorithm based on distributed learning automata for community detection (DLACD) in complex networks. In the proposed algorithm, each vertex of network is equipped with a learning automation. According to the cooperation among network of learning automata and updating action probabilities of each automaton, the algorithm interactively tries to identify high-density local communities. The performance of the proposed algorithm is investigated through a number of simulations on popular synthetic and real networks. Experimental results in comparison with popular community detection algorithms such as walk trap, Danon greedy optimization, Fuzzy community detection, Multi-resolution community detection and label propagation demonstrated the superiority of DLACD in terms of modularity, NMI, performance, min-max-cut and coverage.

Abnormality detection of mammograms by discriminative dictionary learning on DSIFT descriptors.

PubMed

Tavakoli, Nasrin; Karimi, Maryam; Nejati, Mansour; Karimi, Nader; Reza Soroushmehr, S M; Samavi, Shadrokh; Najarian, Kayvan

2017-07-01

Detection and classification of breast lesions using mammographic images are one of the most difficult studies in medical image processing. A number of learning and non-learning methods have been proposed for detecting and classifying these lesions. However, the accuracy of the detection/classification still needs improvement. In this paper we propose a powerful classification method based on sparse learning to diagnose breast cancer in mammograms. For this purpose, a supervised discriminative dictionary learning approach is applied on dense scale invariant feature transform (DSIFT) features. A linear classifier is also simultaneously learned with the dictionary which can effectively classify the sparse representations. Our experimental results show the superior performance of our method compared to existing approaches.

Model-Based Design of Tree WSNs for Decentralized Detection †

PubMed Central

Tantawy, Ashraf; Koutsoukos, Xenofon; Biswas, Gautam

2015-01-01

The classical decentralized detection problem of finding the optimal decision rules at the sensor and fusion center, as well as variants that introduce physical channel impairments have been studied extensively in the literature. The deployment of WSNs in decentralized detection applications brings new challenges to the field. Protocols for different communication layers have to be co-designed to optimize the detection performance. In this paper, we consider the communication network design problem for a tree WSN. We pursue a system-level approach where a complete model for the system is developed that captures the interactions between different layers, as well as different sensor quality measures. For network optimization, we propose a hierarchical optimization algorithm that lends itself to the tree structure, requiring only local network information. The proposed design approach shows superior performance over several contentionless and contention-based network design approaches. PMID:26307989

Cluster Detection Tests in Spatial Epidemiology: A Global Indicator for Performance Assessment

PubMed Central

Guttmann, Aline; Li, Xinran; Feschet, Fabien; Gaudart, Jean; Demongeot, Jacques; Boire, Jean-Yves; Ouchchane, Lemlih

2015-01-01

In cluster detection of disease, the use of local cluster detection tests (CDTs) is current. These methods aim both at locating likely clusters and testing for their statistical significance. New or improved CDTs are regularly proposed to epidemiologists and must be subjected to performance assessment. Because location accuracy has to be considered, performance assessment goes beyond the raw estimation of type I or II errors. As no consensus exists for performance evaluations, heterogeneous methods are used, and therefore studies are rarely comparable. A global indicator of performance, which assesses both spatial accuracy and usual power, would facilitate the exploration of CDTs behaviour and help between-studies comparisons. The Tanimoto coefficient (TC) is a well-known measure of similarity that can assess location accuracy but only for one detected cluster. In a simulation study, performance is measured for many tests. From the TC, we here propose two statistics, the averaged TC and the cumulated TC, as indicators able to provide a global overview of CDTs performance for both usual power and location accuracy. We evidence the properties of these two indicators and the superiority of the cumulated TC to assess performance. We tested these indicators to conduct a systematic spatial assessment displayed through performance maps. PMID:26086911

An Energy-Efficient Multi-Tier Architecture for Fall Detection Using Smartphones.

PubMed

Guvensan, M Amac; Kansiz, A Oguz; Camgoz, N Cihan; Turkmen, H Irem; Yavuz, A Gokhan; Karsligil, M Elif

2017-06-23

Automatic detection of fall events is vital to providing fast medical assistance to the causality, particularly when the injury causes loss of consciousness. Optimization of the energy consumption of mobile applications, especially those which run 24/7 in the background, is essential for longer use of smartphones. In order to improve energy-efficiency without compromising on the fall detection performance, we propose a novel 3-tier architecture that combines simple thresholding methods with machine learning algorithms. The proposed method is implemented on a mobile application, called uSurvive, for Android smartphones. It runs as a background service and monitors the activities of a person in daily life and automatically sends a notification to the appropriate authorities and/or user defined contacts when it detects a fall. The performance of the proposed method was evaluated in terms of fall detection performance and energy consumption. Real life performance tests conducted on two different models of smartphone demonstrate that our 3-tier architecture with feature reduction could save up to 62% of energy compared to machine learning only solutions. In addition to this energy saving, the hybrid method has a 93% of accuracy, which is superior to thresholding methods and better than machine learning only solutions.

The role of Fluorine-18-Fluorodeoxyglucose positron emission tomography in staging and restaging of patients with osteosarcoma

PubMed Central

Quartuccio, Natale; Treglia, Giorgio; Salsano, Marco; Mattoli, Maria Vittoria; Muoio, Barbara; Piccardo, Arnoldo; Lopci, Egesta; Cistaro, Angelina

2013-01-01

Background The objective of this study is to systematically review the role of positron emission tomography (PET) and PET/computed tomography (PET/CT) with Fluorine-18-Fluorodeoxyglucose (FDG) in patients with osteosarcoma (OS). Methods A comprehensive literature search of published studies through October 10th, 2012 in PubMed/MEDLINE, Embase and Scopus databases regarding whole-body FDG-PET and FDG-PET/CT in patients with OS was performed. Results We identified 13 studies including 289 patients with OS. With regard to the staging and restaging of OS, the diagnostic performance of FDG-PET and PET/CT seem to be high; FDG-PET and PET/CT seem to be superior to bone scintigraphy and conventional imaging methods in detecting bone metastases; conversely, spiral CT seems to be superior to FDG-PET in detecting pulmonary metastases from OS Conclusions Metabolic imaging may provide additional information in the evaluation of OS patients. The combination of FDG-PET or FDG-PET/CT with conventional imaging methods seems to be a valuable tool in the staging and restaging of OS and may have a relevant impact on the treatment planning. PMID:23801904

A sound advantage: Increased auditory capacity in autism.

PubMed

Remington, Anna; Fairnie, Jake

2017-09-01

Autism Spectrum Disorder (ASD) has an intriguing auditory processing profile. Individuals show enhanced pitch discrimination, yet often find seemingly innocuous sounds distressing. This study used two behavioural experiments to examine whether an increased capacity for processing sounds in ASD could underlie both the difficulties and enhanced abilities found in the auditory domain. Autistic and non-autistic young adults performed a set of auditory detection and identification tasks designed to tax processing capacity and establish the extent of perceptual capacity in each population. Tasks were constructed to highlight both the benefits and disadvantages of increased capacity. Autistic people were better at detecting additional unexpected and expected sounds (increased distraction and superior performance respectively). This suggests that they have increased auditory perceptual capacity relative to non-autistic people. This increased capacity may offer an explanation for the auditory superiorities seen in autism (e.g. heightened pitch detection). Somewhat counter-intuitively, this same 'skill' could result in the sensory overload that is often reported - which subsequently can interfere with social communication. Reframing autistic perceptual processing in terms of increased capacity, rather than a filtering deficit or inability to maintain focus, increases our understanding of this complex condition, and has important practical implications that could be used to develop intervention programs to minimise the distress that is often seen in response to sensory stimuli. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

How often do surgeons intervene on shoulder labral lesions detected at MR examination? A retrospective review of MR examinations correlated with arthroscopy

PubMed Central

2014-01-01

Objective: We report the prevalence of surgical intervention on shoulder labral lesions detected at MR examinations and how surgeons describe labral tears seen at MR examinations in their arthroscopy reports. Methods: A retrospective review of 100 consecutive patients aged 50 years or younger who had shoulder labral tears on MR and went on to have surgery performed. It was determined whether surgical intervention was performed on the MR lesions. Results: Of these 100 patients, 72 had superior labral anterior to posterior (SLAP) tears, 38 had posterior labral tears and 28 had anterior labral tears on MR examination. All 100 patients went on to arthroscopy. All lesions described on MRI were described on arthroscopy. Of the 72 SLAP tears, 64 were described as fraying on arthroscopy with 51 debrided. The remaining eight SLAP tears were tacked surgically. Of the 38 posterior labral tears, 36 were described as fraying on arthroscopy with 29 debrided and 2 had surgical tacking performed. Of the 28 anterior labral tears described on MR examination, 26 had surgical tacking performed and 2 were debrided. There were four SLAP tears, two anterior labral tears and three posterior labral tears seen on arthroscopy but not seen on MR examination. Conclusion: In this series, a high percentage of SLAP tears and posterior labral tears described on MR examination did not have surgical tacking. Most anterior labral tears had surgical tacking. Based on the above, our surgeons request we describe superior and posterior labral lesions as fraying and/or tearing, unless we can see a displaced tear. Most anterior labral lesions are treated with surgical tacking. Advances in knowledge: MRI allows for sensitive detection of labral tears. The tears often are not clinically significant. PMID:24712320

[Tumor thrombus arising from the superior vena cava and extending into the right atrium in a patient with advanced testicular germ cell tumor].

PubMed

Miyake, Makito; Fujimoto, Kiyohide; Matsushita, Chie; Chihara, Yoshitomo; Tanaka, Masahiro; Hirayama, Akihide; Hirao, Yoshihiko; Uemura, Hirotsugu

2009-06-01

A 24-year-old man was referred to our hospital with a painless mass on the left side of his neck. Ultrasonography detected right testicular tumor and computerized tomography scanning revealed a left supraclavicular lymph node mass and bulky retroperitoneal lymph node mass. He initially underwent right high orchiectomy, combination chemotherapy and retroperitoneal lymph node dissection for advanced testicular non-seminomatous germ cell tumor. Six years later, late relapse was detected in the lung. After complete remission of the lung metastasis with chemotherapy, the serum alpha-fetoprotein began to increase because of superior vena caval thrombus extending into the right atrium. Emergency surgical excision was performed successfully using extracorporeal circulation to prevent pulmonary embolism and the resected specimen pathologically revealed adenocarcinoma interpreted as teratoma malignant transformation. Adjuvant chemotherapy consisting of paclitaxel, ifosfamide and nedaplatin were administered for subsequent slight elevation of serum F-human chorionic gonadotropin beta, resulting in successful normalization again. Later, he suddenly died of cerebral infarction without any evidence of recurrence 138 months after his initial presentation. We report herein an extremely uncommon case of advanced testicular germ cell tumor with development of superior vena caval thrombus extending into the right atrium.

Use of classification trees to apportion single echo detections to species: Application to the pelagic fish community of Lake Superior

USGS Publications Warehouse

Yule, Daniel L.; Adams, Jean V.; Hrabik, Thomas R.; Vinson, Mark R.; Woiak, Zebadiah; Ahrenstroff, Tyler D.

2013-01-01

Acoustic methods are used to estimate the density of pelagic fish in large lakes with results of midwater trawling used to assign species composition. Apportionment in lakes having mixed species can be challenging because only a small fraction of the water sampled acoustically is sampled with trawl gear. Here we describe a new method where single echo detections (SEDs) are assigned to species based on classification tree models developed from catch data that separate species based on fish size and the spatial habitats they occupy. During the summer of 2011, we conducted a spatially-balanced lake-wide acoustic and midwater trawl survey of Lake Superior. A total of 51 sites in four bathymetric depth strata (0–30 m, 30–100 m, 100–200 m, and >200 m) were sampled. We developed classification tree models for each stratum and found fish length was the most important variable for separating species. To apply these trees to the acoustic data, we needed to identify a target strength to length (TS-to-L) relationship appropriate for all abundant Lake Superior pelagic species. We tested performance of 7 general (i.e., multi-species) relationships derived from three published studies. The best-performing relationship was identified by comparing predicted and observed catch compositions using a second independent Lake Superior data set. Once identified, the relationship was used to predict lengths of SEDs from the lake-wide survey, and the classification tree models were used to assign each SED to a species. Exotic rainbow smelt (Osmerus mordax) were the most common species at bathymetric depths 100 m (384 million; 6.0 kt). Cisco (Coregonus artedi) were widely distributed over all strata with their population estimated at 182 million (44 kt). The apportionment method we describe should be transferable to other large lakes provided fish are not tightly aggregated, and an appropriate TS-to-L relationship for abundant pelagic fish species can be determined.

Lightening the load: perceptual load impairs visual detection in typical adults but not in autism.

PubMed

Remington, Anna M; Swettenham, John G; Lavie, Nilli

2012-05-01

Autism spectrum disorder (ASD) research portrays a mixed picture of attentional abilities with demonstrations of enhancements (e.g., superior visual search) and deficits (e.g., higher distractibility). Here we test a potential resolution derived from the Load Theory of Attention (e.g., Lavie, 2005). In Load Theory, distractor processing depends on the perceptual load of the task and as such can only be eliminated under high load that engages full capacity. We hypothesize that ASD involves enhanced perceptual capacity, leading to the superior performance and increased distractor processing previously reported. Using a signal-detection paradigm, we test this directly and demonstrate that, under higher levels of load, perceptual sensitivity was reduced in typical adults but not in adults with ASD. These findings confirm our hypothesis and offer a promising solution to the previous discrepancies by suggesting that increased distractor processing in ASD results not from a filtering deficit but from enhanced perceptual capacity.

Facile synthesis of carbon dots with superior sensing ability

NASA Astrophysics Data System (ADS)

Jin, Lin; Li, Jingguo; Liu, Liyun; Wang, Zhenling; Zhang, Xingcai

2018-04-01

Carbon dots (CDs) have various applications in biomedical and environmental field, such as bio-imaging, bio-sensing and heavy metal detection. In this study, a novel class of CDs were synthesized using a one-step hydrothermal method. The fabricated CDs displayed stable photoluminescence, good water solubility, and photo stability. Moreover, the functional groups (carboxylic acid moieties and hydroxyls) on the surface of the obtained CDs enable it with superior sensing ability (e.g., very low detectable concentration for Pb2+: 5 nmol/L). With superior detection sensitivity, excellent fluorescent properties and facile fabrication method, the as-obtained CDs can find practical applications as cost-effective and sensitive chemo-sensors in water and food safety field.

Lesion Detection in CT Images Using Deep Learning Semantic Segmentation Technique

NASA Astrophysics Data System (ADS)

Kalinovsky, A.; Liauchuk, V.; Tarasau, A.

2017-05-01

In this paper, the problem of automatic detection of tuberculosis lesion on 3D lung CT images is considered as a benchmark for testing out algorithms based on a modern concept of Deep Learning. For training and testing of the algorithms a domestic dataset of 338 3D CT scans of tuberculosis patients with manually labelled lesions was used. The algorithms which are based on using Deep Convolutional Networks were implemented and applied in three different ways including slice-wise lesion detection in 2D images using semantic segmentation, slice-wise lesion detection in 2D images using sliding window technique as well as straightforward detection of lesions via semantic segmentation in whole 3D CT scans. The algorithms demonstrate superior performance compared to algorithms based on conventional image analysis methods.

The Superior-Edge-of-the-Knee Incision Method in Lymphaticovenular Anastomosis for Lower Extremity Lymphedema.

PubMed

Seki, Yukio; Yamamoto, Takumi; Yoshimatsu, Hidehiko; Hayashi, Akitatsu; Kurazono, Arito; Mori, Masanori; Kato, Yoichi; Koshima, Isao

2015-11-01

Lymphatic vessel diameter and lymph flow are important for accurate anastomosis and effective lymph-to-venous flow in lymphaticovenular anastomosis. The authors developed a reliable method, the superioredge-of-the-knee incision method, for detecting and making the best use of high-flow lymphatic vessels in the distal medial thigh between the deep and superficial fascia, where movement of the knee, combined with compression between these fascial layers, theoretically results in upward propulsion of lymphatic fluid. Intraoperative detection of large lymphatic vessels and of venous reflux and postoperative lymphedematous volume reduction were compared between 15 patients in whom lymphaticovenular anastomoses with the superior-edge-of-the-knee incision method were undergone and 15 in whom conventional lymphaticovenular anastomoses were undergone. Lymphaticovenular anastomosis at the thigh yielded 30 anastomoses in the superior-edge-of-the-knee incision group and 32 anastomoses in the non-superior-edge-of-the-knee incision group. Large lymphatic vessels were more frequently found in the superior-edge-of-the-knee incision group than in the non-superior-edge-of-the-knee incision group (60.0 percent versus 18.8 percent; p = 0.002). Venous reflux occurred less frequently in the superior-edge-of-the-knee incision group than in the non-superior-edge-of-the-knee incision group (10.0 percent versus 65.6 percent; p < 0.001). Reduction of the lower extremity lymphedema index was significantly greater in the superior-edge-of-the-knee incision group than in the non-superior-edge-of-the-knee incision group (24.427 ± 12.400 versus 0.032 ± 20.535; p < 0.001). The superior-edge-of-the-knee incision method facilitates detection and use of large, high-flow lymphatic vessels in the distal medial thigh, both of which are important for optimum therapeutic effects in patients with lower extremity lymphedema. Therapeutic, III.

Application of an enhanced fuzzy algorithm for MR brain tumor image segmentation

NASA Astrophysics Data System (ADS)

Hemanth, D. Jude; Vijila, C. Kezi Selva; Anitha, J.

2010-02-01

Image segmentation is one of the significant digital image processing techniques commonly used in the medical field. One of the specific applications is tumor detection in abnormal Magnetic Resonance (MR) brain images. Fuzzy approaches are widely preferred for tumor segmentation which generally yields superior results in terms of accuracy. But most of the fuzzy algorithms suffer from the drawback of slow convergence rate which makes the system practically non-feasible. In this work, the application of modified Fuzzy C-means (FCM) algorithm to tackle the convergence problem is explored in the context of brain image segmentation. This modified FCM algorithm employs the concept of quantization to improve the convergence rate besides yielding excellent segmentation efficiency. This algorithm is experimented on real time abnormal MR brain images collected from the radiologists. A comprehensive feature vector is extracted from these images and used for the segmentation technique. An extensive feature selection process is performed which reduces the convergence time period and improve the segmentation efficiency. After segmentation, the tumor portion is extracted from the segmented image. Comparative analysis in terms of segmentation efficiency and convergence rate is performed between the conventional FCM and the modified FCM. Experimental results show superior results for the modified FCM algorithm in terms of the performance measures. Thus, this work highlights the application of the modified algorithm for brain tumor detection in abnormal MR brain images.

Performance of transport and selective media for swine Bordetella bronchiseptica recovery and it comparison to polymerase chain reaction detection

PubMed Central

Coutinho, Tania Alen; Bernardi, Mari Lourdes; de Itapema Cardoso, Marisa Ribeiro; Borowski, Sandra Maria; Moreno, Andrea Micke; de Barcellos, David Emilio Santos Neves

2009-01-01

Three comparative assays were performed seeking to improve the sensitivity of the diagnosis of Bordetella bronchiseptica infection analyzing swine nasal swabs. An initial assay compared the recovery of B. bronchiseptica from swabs simultaneously inoculated with B. bronchiseptica and some interfering bacteria, immersed into three transport formulations (Amies with charcoal, trypticase soy broth and phosphate buffer according to Soerensen supplemented with 5% of bovine fetal serum) and submitted to different temperatures (10°C and 27°C) and periods of incubation (24, 72 and 120 hours). A subsequent assay compared three selective media (MacConkey agar, modified selective medium G20G and a ceftiofur medium) for their recovery capabilities from clinical specimens. One last assay compared the polymerase chain reaction to the three selective media. In the first assay, the recovery of B. bronchiseptica from transport systems was better at 27°C and the three formulations had good performances at this temperature, but the collection of qualitative and quantitative analysis indicated the advantage of Amies medium for nasal swabs transportation. The second assay indicated that MacConkey agar and modified G20G had similar results and were superior to the ceftiofur medium. In the final assay, polymerase chain reaction presented superior capability of B. bronchiseptica detection to culture procedures. PMID:24031390

Granular Flow Graph, Adaptive Rule Generation and Tracking.

PubMed

Pal, Sankar Kumar; Chakraborty, Debarati Bhunia

2017-12-01

A new method of adaptive rule generation in granular computing framework is described based on rough rule base and granular flow graph, and applied for video tracking. In the process, several new concepts and operations are introduced, and methodologies formulated with superior performance. The flow graph enables in defining an intelligent technique for rule base adaptation where its characteristics in mapping the relevance of attributes and rules in decision-making system are exploited. Two new features, namely, expected flow graph and mutual dependency between flow graphs are defined to make the flow graph applicable in the tasks of both training and validation. All these techniques are performed in neighborhood granular level. A way of forming spatio-temporal 3-D granules of arbitrary shape and size is introduced. The rough flow graph-based adaptive granular rule-based system, thus produced for unsupervised video tracking, is capable of handling the uncertainties and incompleteness in frames, able to overcome the incompleteness in information that arises without initial manual interactions and in providing superior performance and gaining in computation time. The cases of partial overlapping and detecting the unpredictable changes are handled efficiently. It is shown that the neighborhood granulation provides a balanced tradeoff between speed and accuracy as compared to pixel level computation. The quantitative indices used for evaluating the performance of tracking do not require any information on ground truth as in the other methods. Superiority of the algorithm to nonadaptive and other recent ones is demonstrated extensively.

TREFEX: Trend Estimation and Change Detection in the Response of MOX Gas Sensors

PubMed Central

Pashami, Sepideh; Lilienthal, Achim J.; Schaffernicht, Erik; Trincavelli, Marco

2013-01-01

Many applications of metal oxide gas sensors can benefit from reliable algorithms to detect significant changes in the sensor response. Significant changes indicate a change in the emission modality of a distant gas source and occur due to a sudden change of concentration or exposure to a different compound. As a consequence of turbulent gas transport and the relatively slow response and recovery times of metal oxide sensors, their response in open sampling configuration exhibits strong fluctuations that interfere with the changes of interest. In this paper we introduce TREFEX, a novel change point detection algorithm, especially designed for metal oxide gas sensors in an open sampling system. TREFEX models the response of MOX sensors as a piecewise exponential signal and considers the junctions between consecutive exponentials as change points. We formulate non-linear trend filtering and change point detection as a parameter-free convex optimization problem for single sensors and sensor arrays. We evaluate the performance of the TREFEX algorithm experimentally for different metal oxide sensors and several gas emission profiles. A comparison with the previously proposed GLR method shows a clearly superior performance of the TREFEX algorithm both in detection performance and in estimating the change time. PMID:23736853

Detailed anatomy of the abducens nerve in the lateral rectus muscle.

PubMed

Nam, Yong Seok; Kim, In-Beom; Shin, Sun Young

2017-10-01

The aims of this study were to elucidate the detailed anatomy of the abducens nerve in the lateral rectus muscle (LRM) and the intramuscular innervation pattern using Sihler staining. In this cohort study, 32 eyes of 16 cadavers were assessed. Dissection was performed from the LRM origin to its insertion. The following distances were measured: from LRM insertion to the bifurcation point of the abducens nerve, from LRM insertion to the entry site of the superior branch or inferior branch, from the upper border of the LRM to the entry site of the superior branch, from the lower border of LRM to the entry site of inferior branch, and the widths of the main trunk and superior and inferior branches. The single trunk of the abducens nerve divided into two branches 37 mm from insertion of the LRM, and 22 of 32 (68.8%) orbits showed only two superior and inferior branches with no subdivision. The superior branch entered the LRM more anteriorly (P = 0.037) and the superior branch was thinner than the inferior branch (P = 0.040). The most distally located intramuscular nerve ending was observed at 52.9 ± 3.5% of the length of each muscle. Non-overlap between the superior and inferior intramuscular arborization of the nerve was detected in 27 of 32 cases (84.4%). Five cases (15.6%) showed definite overlap of the superior and inferior zones. This study revealed the detailed anatomy of the abducens nerve in the LRM and provides helpful information to understand abducens nerve palsy. Clin. Anat. 30:873-877, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Autoregressive statistical pattern recognition algorithms for damage detection in civil structures

NASA Astrophysics Data System (ADS)

Yao, Ruigen; Pakzad, Shamim N.

2012-08-01

Statistical pattern recognition has recently emerged as a promising set of complementary methods to system identification for automatic structural damage assessment. Its essence is to use well-known concepts in statistics for boundary definition of different pattern classes, such as those for damaged and undamaged structures. In this paper, several statistical pattern recognition algorithms using autoregressive models, including statistical control charts and hypothesis testing, are reviewed as potentially competitive damage detection techniques. To enhance the performance of statistical methods, new feature extraction techniques using model spectra and residual autocorrelation, together with resampling-based threshold construction methods, are proposed. Subsequently, simulated acceleration data from a multi degree-of-freedom system is generated to test and compare the efficiency of the existing and proposed algorithms. Data from laboratory experiments conducted on a truss and a large-scale bridge slab model are then used to further validate the damage detection methods and demonstrate the superior performance of proposed algorithms.

An Energy-Efficient Multi-Tier Architecture for Fall Detection on Smartphones

PubMed Central

Guvensan, M. Amac; Kansiz, A. Oguz; Camgoz, N. Cihan; Turkmen, H. Irem; Yavuz, A. Gokhan; Karsligil, M. Elif

2017-01-01

Automatic detection of fall events is vital to providing fast medical assistance to the causality, particularly when the injury causes loss of consciousness. Optimization of the energy consumption of mobile applications, especially those which run 24/7 in the background, is essential for longer use of smartphones. In order to improve energy-efficiency without compromising on the fall detection performance, we propose a novel 3-tier architecture that combines simple thresholding methods with machine learning algorithms. The proposed method is implemented on a mobile application, called uSurvive, for Android smartphones. It runs as a background service and monitors the activities of a person in daily life and automatically sends a notification to the appropriate authorities and/or user defined contacts when it detects a fall. The performance of the proposed method was evaluated in terms of fall detection performance and energy consumption. Real life performance tests conducted on two different models of smartphone demonstrate that our 3-tier architecture with feature reduction could save up to 62% of energy compared to machine learning only solutions. In addition to this energy saving, the hybrid method has a 93% of accuracy, which is superior to thresholding methods and better than machine learning only solutions. PMID:28644378

Super-recognition in development: A case study of an adolescent with extraordinary face recognition skills.

PubMed

Bennetts, Rachel J; Mole, Joseph; Bate, Sarah

2017-09-01

Face recognition abilities vary widely. While face recognition deficits have been reported in children, it is unclear whether superior face recognition skills can be encountered during development. This paper presents O.B., a 14-year-old female with extraordinary face recognition skills: a "super-recognizer" (SR). O.B. demonstrated exceptional face-processing skills across multiple tasks, with a level of performance that is comparable to adult SRs. Her superior abilities appear to be specific to face identity: She showed an exaggerated face inversion effect and her superior abilities did not extend to object processing or non-identity aspects of face recognition. Finally, an eye-movement task demonstrated that O.B. spent more time than controls examining the nose - a pattern previously reported in adult SRs. O.B. is therefore particularly skilled at extracting and using identity-specific facial cues, indicating that face and object recognition are dissociable during development, and that super recognition can be detected in adolescence.

Action detection by double hierarchical multi-structure space-time statistical matching model

NASA Astrophysics Data System (ADS)

Han, Jing; Zhu, Junwei; Cui, Yiyin; Bai, Lianfa; Yue, Jiang

2018-03-01

Aimed at the complex information in videos and low detection efficiency, an actions detection model based on neighboring Gaussian structure and 3D LARK features is put forward. We exploit a double hierarchical multi-structure space-time statistical matching model (DMSM) in temporal action localization. First, a neighboring Gaussian structure is presented to describe the multi-scale structural relationship. Then, a space-time statistical matching method is proposed to achieve two similarity matrices on both large and small scales, which combines double hierarchical structural constraints in model by both the neighboring Gaussian structure and the 3D LARK local structure. Finally, the double hierarchical similarity is fused and analyzed to detect actions. Besides, the multi-scale composite template extends the model application into multi-view. Experimental results of DMSM on the complex visual tracker benchmark data sets and THUMOS 2014 data sets show the promising performance. Compared with other state-of-the-art algorithm, DMSM achieves superior performances.

Advances in SAW gas sensors based on the condensate-adsorption effect.

PubMed

Liu, Jiuling; Wang, Wen; Li, Shunzhou; Liu, Minghua; He, Shitang

2011-01-01

A surface-acoustic-wave (SAW) gas sensor with a low detection limit and fast response for volatile organic compounds (VOCs) based on the condensate-adsorption effect detection is developed. In this sensor a gas chromatography (GC) column acts as the separator element and a dual-resonator oscillator acts as the detector element. Regarding the surface effective permittivity method, the response mechanism analysis, which relates the condensate-adsorption effect, is performed, leading to the sensor performance prediction prior to fabrication. New designs of SAW resonators, which act as feedback of the oscillator, are devised in order to decrease the insertion loss and to achieve single-mode control, resulting in superior frequency stability of the oscillator. Based on the new phase modulation approach, excellent short-term frequency stability (±3 Hz/s) is achieved with the SAW oscillator by using the 500 MHz dual-port resonator as feedback element. In a sensor experiment investigating formaldehyde detection, the implemented SAW gas sensor exhibits an excellent threshold detection limit as low as 0.38 pg.

Action detection by double hierarchical multi-structure space–time statistical matching model

NASA Astrophysics Data System (ADS)

Han, Jing; Zhu, Junwei; Cui, Yiyin; Bai, Lianfa; Yue, Jiang

2018-06-01

Aimed at the complex information in videos and low detection efficiency, an actions detection model based on neighboring Gaussian structure and 3D LARK features is put forward. We exploit a double hierarchical multi-structure space-time statistical matching model (DMSM) in temporal action localization. First, a neighboring Gaussian structure is presented to describe the multi-scale structural relationship. Then, a space-time statistical matching method is proposed to achieve two similarity matrices on both large and small scales, which combines double hierarchical structural constraints in model by both the neighboring Gaussian structure and the 3D LARK local structure. Finally, the double hierarchical similarity is fused and analyzed to detect actions. Besides, the multi-scale composite template extends the model application into multi-view. Experimental results of DMSM on the complex visual tracker benchmark data sets and THUMOS 2014 data sets show the promising performance. Compared with other state-of-the-art algorithm, DMSM achieves superior performances.

Indocyanine Green Videoangiography Transoptic Visualization and Clipping Confirmation of an Optic Splitting Ophthalmic Artery Aneurysm.

PubMed

Rustemi, Oriela; Cester, Giacomo; Causin, Francesco; Scienza, Renato; Della Puppa, Alessandro

2016-06-01

Ophthalmic artery aneurysms with medial and superior projection in exceptionally rare cases can split the optic nerve. Treatment of these aneurysms is challenging, because the aneurysm dome is hidden from the optic nerve, rendering its visualization and clipping confirmation difficult. In addition, optic nerve function should be preserved during surgical maneuvers. Preoperative detection of this growing feature is usually missing. We illustrate the first case of indocyanine green videoangiography (ICG-VA) application in an optic penetrating ophthalmic artery aneurysm treatment. A 57-year-old woman presented with temporal hemianopsia, slight right visual acuity deficit, and new onset of headache. The cerebral angiography detected a right ophthalmic artery aneurysm medially and superiorly projecting. The A1 tract of the ipsilateral anterior cerebral artery was elevated and curved, being suspicious for an under optic aneurysm growth. Surgery was performed. Initially the aneurysm was not visible. ICG-VA permitted the transoptic aneurysm visualization. After optic canal opening, the aneurysm was clipped and transoptic ICG-VA confirmed the aneurysm occlusion. ICG-VA showed also the slight improvement of the optic nerve pial vascularization. Postoperatively, the visual acuity was 10/10 and the hemianopsia did not worsen. The elevation and curve of the A1 tract in medially and superiorly projecting ophthalmic aneurysms may be an indirect sign of under optic growth, or optic splitting aneurysms. ICG-VA transoptic aneurysm detection and occlusion confirmation reduces the surgical maneuvers on the optic nerve, contributing to function preservation. Copyright © 2016 Elsevier Inc. All rights reserved.

Assessing the detectability of antioxidants in two-dimensional high-performance liquid chromatography.

PubMed

Bassanese, Danielle N; Conlan, Xavier A; Barnett, Neil W; Stevenson, Paul G

2015-05-01

This paper explores the analytical figures of merit of two-dimensional high-performance liquid chromatography for the separation of antioxidant standards. The cumulative two-dimensional high-performance liquid chromatography peak area was calculated for 11 antioxidants by two different methods--the areas reported by the control software and by fitting the data with a Gaussian model; these methods were evaluated for precision and sensitivity. Both methods demonstrated excellent precision in regards to retention time in the second dimension (%RSD below 1.16%) and cumulative second dimension peak area (%RSD below 3.73% from the instrument software and 5.87% for the Gaussian method). Combining areas reported by the high-performance liquid chromatographic control software displayed superior limits of detection, in the order of 1 × 10(-6) M, almost an order of magnitude lower than the Gaussian method for some analytes. The introduction of the countergradient eliminated the strong solvent mismatch between dimensions, leading to a much improved peak shape and better detection limits for quantification. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Point target detection utilizing super-resolution strategy for infrared scanning oversampling system

NASA Astrophysics Data System (ADS)

Wang, Longguang; Lin, Zaiping; Deng, Xinpu; An, Wei

2017-11-01

To improve the resolution of remote sensing infrared images, infrared scanning oversampling system is employed with information amount quadrupled, which contributes to the target detection. Generally the image data from double-line detector of infrared scanning oversampling system is shuffled to a whole oversampled image to be post-processed, whereas the aliasing between neighboring pixels leads to image degradation with a great impact on target detection. This paper formulates a point target detection method utilizing super-resolution (SR) strategy concerning infrared scanning oversampling system, with an accelerated SR strategy proposed to realize fast de-aliasing of the oversampled image and an adaptive MRF-based regularization designed to achieve the preserving and aggregation of target energy. Extensive experiments demonstrate the superior detection performance, robustness and efficiency of the proposed method compared with other state-of-the-art approaches.

Syndromic surveillance using veterinary laboratory data: data pre-processing and algorithm performance evaluation

PubMed Central

Dórea, Fernanda C.; McEwen, Beverly J.; McNab, W. Bruce; Revie, Crawford W.; Sanchez, Javier

2013-01-01

Diagnostic test orders to an animal laboratory were explored as a data source for monitoring trends in the incidence of clinical syndromes in cattle. Four years of real data and over 200 simulated outbreak signals were used to compare pre-processing methods that could remove temporal effects in the data, as well as temporal aberration detection algorithms that provided high sensitivity and specificity. Weekly differencing demonstrated solid performance in removing day-of-week effects, even in series with low daily counts. For aberration detection, the results indicated that no single algorithm showed performance superior to all others across the range of outbreak scenarios simulated. Exponentially weighted moving average charts and Holt–Winters exponential smoothing demonstrated complementary performance, with the latter offering an automated method to adjust to changes in the time series that will likely occur in the future. Shewhart charts provided lower sensitivity but earlier detection in some scenarios. Cumulative sum charts did not appear to add value to the system; however, the poor performance of this algorithm was attributed to characteristics of the data monitored. These findings indicate that automated monitoring aimed at early detection of temporal aberrations will likely be most effective when a range of algorithms are implemented in parallel. PMID:23576782

Syndromic surveillance using veterinary laboratory data: data pre-processing and algorithm performance evaluation.

PubMed

Dórea, Fernanda C; McEwen, Beverly J; McNab, W Bruce; Revie, Crawford W; Sanchez, Javier

2013-06-06

Diagnostic test orders to an animal laboratory were explored as a data source for monitoring trends in the incidence of clinical syndromes in cattle. Four years of real data and over 200 simulated outbreak signals were used to compare pre-processing methods that could remove temporal effects in the data, as well as temporal aberration detection algorithms that provided high sensitivity and specificity. Weekly differencing demonstrated solid performance in removing day-of-week effects, even in series with low daily counts. For aberration detection, the results indicated that no single algorithm showed performance superior to all others across the range of outbreak scenarios simulated. Exponentially weighted moving average charts and Holt-Winters exponential smoothing demonstrated complementary performance, with the latter offering an automated method to adjust to changes in the time series that will likely occur in the future. Shewhart charts provided lower sensitivity but earlier detection in some scenarios. Cumulative sum charts did not appear to add value to the system; however, the poor performance of this algorithm was attributed to characteristics of the data monitored. These findings indicate that automated monitoring aimed at early detection of temporal aberrations will likely be most effective when a range of algorithms are implemented in parallel.

Comparative evaluation of diagnostic tests for the detection of Mycobacterium avium subsp. paratuberculosis in the tissues of sheep affected with distinct pathology of paratuberculosis.

PubMed

Sonawane, Ganesh G; Tripathi, Bhupendra N

2016-12-01

Paratuberculosis or Johne's disease is a chronic infectious granulomatous enteritis, mainly of cattle, sheep, goats, and other domestic and wild animals caused by Mycobacterium avium subsp. paratuberculosis (MAP). Currently, MAP has been recognized as an important animal pathogen with significant zoonotic and public health concerns. The early detection of infected animals using suitable diagnostic methods helps in developing control and preventive strategies for the herd. Therefore, the present study was aimed to determine the comparative efficacy of certain diagnostic methods used in the identification and confirmation of MAP in the ovine tissues with distinct pathology of paratuberculosis. The ileum and mesenteric lymph node (MLN) tissues were collected from 38 sheep infected with paratuberculosis from organized farms of Rajasthan. These animals were further classified as paucibacillary (PB; n=15) or multibacillary (MB; n=23) on the basis of histopathological findings and mycobacterial loads. The ileum and MLN tissues of these animals were subjected to IS900 and 251 gene polymerase chain reaction (PCR) and bacterial culture. The tissue sections from MB, PB, and uninfected control sheep groups were stained using indirect immunoperoxidase technique (IPT) and Ziehl-Neelsen (ZN) method. On bacterial culture examination of the ileum and MLN tissues using Herrold's egg yolk medium, MAP was isolated in 14 (60.9%) MB and 5 (33.3%) PB sheep. Of 38 sheep, IS900 PCR detected 21 (55.2%) positive for MAP, of which 19 (82.6%) were MB and 2 (13.3%) were PB sheep. Similarly, 251 gene PCR detected 25 (65.7%) sheep positive for MAP infection, of which 21 (91.3%) were MB and 4 (27%) were PB sheep. Thus, 251 gene PCR was found superior to IS900 PCR in the detection of MAP from the tissues. In PB sheep, IPT and ZN tests were positive in 87.5% and 50% of ileum sections and 70% and 37.5% in MLN sections, respectively. In MB sheep, IPT and ZN tests detected all animals as positive for MAP organisms or antigen and had equal sensitivity in the detection of MAP. The overall sensitivity of IPT was found superior (95%) to ZN staining (80%) in the demonstration of acid-fast bacteria or its antigen in the tissues. The sensitivity of all the tests in the detection of MAP was lower in PB sheep than in MB sheep. Bacterial culture detected MAP in only 50% of sheep and was found less sensitive than other tests used in the present study. Comparing the overall sensitivity of both the PCR assays, 251 gene PCR was found superior to IS900 gene PCR. The sensitivity of IPT was found superior (95%) to the ZN staining (80%) in the demonstration of acid-fast bacteria in the tissues. In the present study, IPT was found superior in the detection of MAP in PB and MB form of ovine paratuberculosis. This test can be used in the confirmation of post mortem diagnosis and research of paratuberculosis along with histopathology. However, 251 gene PCR assay was found easier to perform than IPT and could be used as paratuberculosis screening test in endemic sheep farms for blood and fecal samples. Copyright © 2016.

Barcode DNA length polymorphisms vs fatty acid profiling for adulteration detection in olive oil.

PubMed

Uncu, Ali Tevfik; Uncu, Ayse Ozgur; Frary, Anne; Doganlar, Sami

2017-04-15

The aim of this study was to compare the performance of a DNA-barcode assay with fatty acid profile analysis to authenticate the botanical origin of olive oil. To achieve this aim, we performed a PCR-capillary electrophoresis (PCR-CE) approach on olive oil: seed oil blends using the plastid trnL (UAA) intron barcode. In parallel to genomic analysis, we subjected the samples to gas chromatography analysis of fatty acid composition. While the PCR-CE assay proved equally efficient as gas chromatography analysis in detecting adulteration with soybean, palm, rapeseed, sunflower, sesame, cottonseed and peanut oils, it was superior to the widely utilized analytical chemistry approach in revealing the adulterant species and detecting small quantities of corn and safflower oils in olive oil. Moreover, the DNA-based test correctly identified all tested olive oil: hazelnut oil blends whereas it was not feasible to detect hazelnut oil adulteration through fatty acid profile analysis. Thus, the present research has shown the feasibility of a PCR-CE barcode assay to detect adulteration in olive oil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development of a morphological convolution operator for bearing fault detection

NASA Astrophysics Data System (ADS)

Li, Yifan; Liang, Xihui; Liu, Weiwei; Wang, Yan

2018-05-01

This paper presents a novel signal processing scheme, namely morphological convolution operator (MCO) lifted morphological undecimated wavelet (MUDW), for rolling element bearing fault detection. In this scheme, a MCO is first designed to fully utilize the advantage of the closing & opening gradient operator and the closing-opening & opening-closing gradient operator for feature extraction as well as the merit of excellent denoising characteristics of the convolution operator. The MCO is then introduced into MUDW for the purpose of improving the fault detection ability of the reported MUDWs. Experimental vibration signals collected from a train wheelset test rig and the bearing data center of Case Western Reserve University are employed to evaluate the effectiveness of the proposed MCO lifted MUDW on fault detection of rolling element bearings. The results show that the proposed approach has a superior performance in extracting fault features of defective rolling element bearings. In addition, comparisons are performed between two reported MUDWs and the proposed MCO lifted MUDW. The MCO lifted MUDW outperforms both of them in detection of outer race faults and inner race faults of rolling element bearings.

Technology for low-cost PIR security sensors

NASA Astrophysics Data System (ADS)

Liddiard, Kevin C.

2008-03-01

Current passive infrared (PIR) security sensors employing pyroelectric detectors are simple, cheap and reliable, but have several deficiencies. These sensors, developed two decades ago, are essentially short-range moving-target hotspot detectors. They cannot detect slow temperature changes, and thus are unable to respond to radiation stimuli indicating potential danger such as overheating electrical appliances and developing fires. They have a poor optical resolution and limited ability to recognize detected targets. Modern uncooled thermal infrared technology has vastly superior performance but as yet is too costly to challenge the PIR security sensor market. In this paper microbolometer technology will be discussed which can provide enhanced performance at acceptable cost. In addition to security sensing the technology has numerous applications in the military, industrial and domestic markets where target range is short and low cost is paramount.

Quantifying palpation techniques in relation to performance in a clinical prostate exam.

PubMed

Wang, Ninghuan; Gerling, Gregory J; Childress, Reba Moyer; Martin, Marcus L

2010-07-01

This paper seeks to quantify finger palpation techniques in the prostate clinical exam, determine their relationship with performance in detecting abnormalities, and differentiate the tendencies of nurse practitioner students and resident physicians. One issue with the digital rectal examination (DRE) is that performance in detecting abnormalities varies greatly and agreement between examiners is low. The utilization of particular palpation techniques may be one way to improve clinician ability. Based on past qualitative instruction, this paper algorithmically defines a set of palpation techniques for the DRE, i.e., global finger movement (GFM), local finger movement (LFM), and average intentional finger pressure, and utilizes a custom-built simulator to analyze finger movements in an experiment with two groups: 18 nurse practitioner students and 16 resident physicians. Although technique utilization varied, some elements clearly impacted performance. For example, those utilizing the LFM of vibration were significantly better at detecting abnormalities. Also, the V GFM led to greater success, but finger pressure played a lesser role. Interestingly, while the residents were clearly the superior performers, their techniques differed only subtly from the students. In summary, the quantified palpation techniques appear to account for examination ability at some level, but not entirely for differences between groups.

QRS Detection Algorithm for Telehealth Electrocardiogram Recordings.

PubMed

Khamis, Heba; Weiss, Robert; Xie, Yang; Chang, Chan-Wei; Lovell, Nigel H; Redmond, Stephen J

2016-07-01

QRS detection algorithms are needed to analyze electrocardiogram (ECG) recordings generated in telehealth environments. However, the numerous published QRS detectors focus on clean clinical data. Here, a "UNSW" QRS detection algorithm is described that is suitable for clinical ECG and also poorer quality telehealth ECG. The UNSW algorithm generates a feature signal containing information about ECG amplitude and derivative, which is filtered according to its frequency content and an adaptive threshold is applied. The algorithm was tested on clinical and telehealth ECG and the QRS detection performance is compared to the Pan-Tompkins (PT) and Gutiérrez-Rivas (GR) algorithm. For the MIT-BIH Arrhythmia database (virtually artifact free, clinical ECG), the overall sensitivity (Se) and positive predictivity (+P) of the UNSW algorithm was >99%, which was comparable to PT and GR. When applied to the MIT-BIH noise stress test database (clinical ECG with added calibrated noise) after artifact masking, all three algorithms had overall Se >99%, and the UNSW algorithm had higher +P (98%, p < 0.05) than PT and GR. For 250 telehealth ECG records (unsupervised recordings; dry metal electrodes), the UNSW algorithm had 98% Se and 95% +P which was superior to PT (+P: p < 0.001) and GR (Se and +P: p < 0.001). This is the first study to describe a QRS detection algorithm for telehealth data and evaluate it on clinical and telehealth ECG with superior results to published algorithms. The UNSW algorithm could be used to manage increasing telehealth ECG analysis workloads.

Visual processing in adolescents with autism spectrum disorder: evidence from embedded figures and configural superiority tests.

PubMed

Dillen, Claudia; Steyaert, Jean; Op de Beeck, Hans P; Boets, Bart

2015-05-01

The embedded figures test has often been used to reveal weak central coherence in individuals with autism spectrum disorder (ASD). Here, we administered a more standardized automated version of the embedded figures test in combination with the configural superiority task, to investigate the effect of contextual modulation on local feature detection in 23 adolescents with ASD and 26 matched typically developing controls. On both tasks both groups performed largely similarly in terms of accuracy and reaction time, and both displayed the contextual modulation effect. This indicates that individuals with ASD are equally sensitive compared to typically developing individuals to the contextual effects of the task and that there is no evidence for a local processing bias in adolescents with ASD.

Molecular engineering of a dual emission near-infrared ratiometric fluorophore for the detection of pH at the organism level.

PubMed

Wang, Bo-Lin; Jiang, Chuang; Li, Kun; Liu, Yan-Hong; Xie, Yongmei; Yu, Xiao-Qi

2015-07-07

A near-infrared ratiometric fluorophore (NIR-HBT) was rationally designed and constructed by expanding both the excitation and emission wavelength of the classical ratiometric fluorophore 2-(benzothiazol-2-yl)phenol (HBT) into the near-infrared region. The NIR-HBT was easily synthesized by incorporating the HBT module into the hemicyanine skeleton and showed evident NIR ratiometric fluorophore characteristics. Further application of the new fluorophore for pH detection demonstrated that NIR-HBT possesses superior overall analytical performance and NIR-HBT was successfully applied for detection of acidosis caused by inflammation in living animal tissue, which indicated the potential application value of NIR-HBT in biological imaging and sensing.

Minimal time change detection algorithm for reconfigurable control system and application to aerospace

NASA Technical Reports Server (NTRS)

Kim, Sungwan

1994-01-01

System parameters should be tracked on-line to build a reconfigurable control system even though there exists an abrupt change. For this purpose, a new performance index that we are studying is the speed of adaptation- how quickly does the system determine that a change has occurred? In this paper, a new, robust algorithm that is optimized to minimize the time delay in detecting a change for fixed false alarm probability is proposed. Simulation results for the aircraft lateral motion with a known or unknown change in control gain matrices, in the presence of doublet input, indicate that the algorithm works fairly well. One of its distinguishing properties is that detection delay of this algorithm is superior to that of Whiteness Test.

Gender and practical skill performance in science

NASA Astrophysics Data System (ADS)

Lock, Roger

The performance of 18 boys and 18 girls on four problem-solving tasks set in science contexts was compared. The tasks were administered in a one-to-one testing situation and assessments were made by direct observation, questioning, and by using written records. The tasks were valid and reliable, and the samples of boys and girls were matched for ability and curriculum background. Past studies have identified gender differences in performance on science tasks; however, this study found little evidence to support these findings. Few significant differences in performance were found. No gender differences were detected in observation, reporting, or planning skills, and there was no differential performance on the use of scientific language. Girls performed less well in relation to self-reliance, and performance differences on the interpretation skill approached significance with boys' performance superior.

Gaze Behavior of Gymnastics Judges: Where Do Experienced Judges and Gymnasts Look While Judging?

PubMed

Pizzera, Alexandra; Möller, Carsten; Plessner, Henning

2018-03-01

Gymnastics judges and former gymnasts have been shown to be quite accurate in detecting errors and accurately judging performance. The purpose of the current study was to examine if this superior judging performance is reflected in judges' gaze behavior. Thirty-five judges were asked to judge 21 gymnasts who performed a skill on the vault in a video-based test. Classifying 1 sample on 2 different criteria, judging performance and gaze behavior were compared between judges with a higher license level and judges with a lower license level and between judges who were able to perform the skill (specific motor experience [SME]) and those who were not. The results revealed better judging performance among judges with a higher license level compared with judges with a lower license level and more fixations on the gymnast during the whole skill and the landing phase, specifically on the head and arms of the gymnast. Specific motor experience did not result in any differences in judging performance; however, judges with SME showed similar gaze patterns to those of judges with a high license level, with 1 difference in their increased focus on the gymnasts' feet. Superior judging performance seems to be reflected in a specific gaze behavior. This gaze behavior appears to partly stem from judges' own sensorimotor experiences for this skill and reflects the gymnasts' perspective onto the skill.

Planar junctionless phototransistor: A potential high-performance and low-cost device for optical-communications

NASA Astrophysics Data System (ADS)

Ferhati, H.; Djeffal, F.

2017-12-01

In this paper, a new junctionless optical controlled field effect transistor (JL-OCFET) and its comprehensive theoretical model is proposed to achieve high optical performance and low cost fabrication process. Exhaustive study of the device characteristics and comparison between the proposed junctionless design and the conventional inversion mode structure (IM-OCFET) for similar dimensions are performed. Our investigation reveals that the proposed design exhibits an outstanding capability to be an alternative to the IM-OCFET due to the high performance and the weak signal detection benefit offered by this design. Moreover, the developed analytical expressions are exploited to formulate the objective functions to optimize the device performance using Genetic Algorithms (GAs) approach. The optimized JL-OCFET not only demonstrates good performance in terms of derived drain current and responsivity, but also exhibits superior signal to noise ratio, low power consumption, high-sensitivity, high ION/IOFF ratio and high-detectivity as compared to the conventional IM-OCFET counterpart. These characteristics make the optimized JL-OCFET potentially suitable for developing low cost and ultrasensitive photodetectors for high-performance and low cost inter-chips data communication applications.

A study of Minnesota forests and lakes using data from Earth Resources Technology Satellites

NASA Technical Reports Server (NTRS)

1974-01-01

Highlights of research and practical benefits are discussed for the following projects which utilized ERTS 1 data to provide municipal, state, federal, and industrial users with environmental resource information for the state of Minnesota: (1) forest disease detection and control; (2) evaluation of water quality by remote sensing techniques; (3) forest vegetation classification and management; (4) detection of saline soils in the Red River Valley; (5) snowmelt flood prediction; (6) remote sensing applications to hydrology; (7) Rice Creek watershed project; (8) water quality in Lake Superior and the Duluth Superior Harbor; and (9) determination of Lake Superior currents from turbidity patterns.

Phase magnification by two-axis countertwisting for detection-noise robust interferometry

NASA Astrophysics Data System (ADS)

Anders, Fabian; Pezzè, Luca; Smerzi, Augusto; Klempt, Carsten

2018-04-01

Entanglement-enhanced atom interferometry has the potential of surpassing the standard quantum limit and eventually reaching the ultimate Heisenberg bound. The experimental progress is, however, hindered by various technical noise sources, including the noise in the detection of the output quantum state. The influence of detection noise can be largely overcome by exploiting echo schemes, where the entanglement-generating interaction is repeated after the interferometer sequence. Here, we propose an echo protocol that uses two-axis countertwisting as the main nonlinear interaction. We demonstrate that the scheme is robust to detection noise and its performance is superior compared to the already demonstrated one-axis twisting echo scheme. In particular, the sensitivity maintains the Heisenberg scaling in the limit of a large particle number. Finally, we show that the protocol can be implemented with spinor Bose-Einstein condensates. Our results thus outline a realistic approach to mitigate the detection noise in quantum-enhanced interferometry.

A multistage approach to improve performance of computer-aided detection of pulmonary embolisms depicted on CT images: preliminary investigation.

PubMed

Park, Sang Cheol; Chapman, Brian E; Zheng, Bin

2011-06-01

This study developed a computer-aided detection (CAD) scheme for pulmonary embolism (PE) detection and investigated several approaches to improve CAD performance. In the study, 20 computed tomography examinations with various lung diseases were selected, which include 44 verified PE lesions. The proposed CAD scheme consists of five basic steps: 1) lung segmentation; 2) PE candidate extraction using an intensity mask and tobogganing region growing; 3) PE candidate feature extraction; 4) false-positive (FP) reduction using an artificial neural network (ANN); and 5) a multifeature-based k-nearest neighbor for positive/negative classification. In this study, we also investigated the following additional methods to improve CAD performance: 1) grouping 2-D detected features into a single 3-D object; 2) selecting features with a genetic algorithm (GA); and 3) limiting the number of allowed suspicious lesions to be cued in one examination. The results showed that 1) CAD scheme using tobogganing, an ANN, and grouping method achieved the maximum detection sensitivity of 79.2%; 2) the maximum scoring method achieved the superior performance over other scoring fusion methods; 3) GA was able to delete "redundant" features and further improve CAD performance; and 4) limiting the maximum number of cued lesions in an examination reduced FP rate by 5.3 times. Combining these approaches, CAD scheme achieved 63.2% detection sensitivity with 18.4 FP lesions per examination. The study suggested that performance of CAD schemes for PE detection depends on many factors that include 1) optimizing the 2-D region grouping and scoring methods; 2) selecting the optimal feature set; and 3) limiting the number of allowed cueing lesions per examination.

Ionic effect investigation of a potentiometric sensor for urea and surface morphology observation of entrapped urease/polypyrrole matrix.

PubMed

Syu, Mei-Jywan; Chang, Yu-Sung

2009-04-15

Potentio-dynamic polymerization of buffered urease and pyrrole monomer onto carbon papers was conducted to fabricate an immobilized urease electrode for measuring the urea concentration. To use carbon paper as the substrate for the electro-growth of polypyrrole matrix not only created sufficient adhesion of the conducting polymer layer but also provided superior entrapment of urease enzymes. The potentiometric response corresponding to ammonia, the product formed from the urease catalyzed urea reaction, was employed for the urea concentration measurement. Scanning electron microscopic photographs showed that the polypyrrole matrix deposited on the carbon papers appeared to be of a cylindrical nanotube shape. The charge density applied in the polymerization was found to affect the potentiometric response while the potential-scanning rate showed minor influence. The composite electrodes had high sensitivity in urea detection, showing a response linear to the logarithm of the urea concentration in the range of 10(-3) to 10 mM. The detection of urea solution prepared in water and buffer was also compared. Ionic effect on the sensing of urea solution was investigated. By comparing the data reported in literature, the urease/polypyrrole/carbon paper electrode developed in this work showed superior long-term stability and reusability. The detection of urea in serum was also well performed.

Neural basis of superior performance of action videogame players in an attention-demanding task.

PubMed

Mishra, Jyoti; Zinni, Marla; Bavelier, Daphne; Hillyard, Steven A

2011-01-19

Steady-state visual evoked potentials (SSVEPs) were recorded from action videogame players (VGPs) and from non-videogame players (NVGPs) during an attention-demanding task. Participants were presented with a multi-stimulus display consisting of rapid sequences of alphanumeric stimuli presented at rates of 8.6/12 Hz in the left/right peripheral visual fields, along with a central square at fixation flashing at 5.5 Hz and a letter sequence flashing at 15 Hz at an upper central location. Subjects were cued to attend to one of the peripheral or central stimulus sequences and detect occasional targets. Consistent with previous behavioral studies, VGPs detected targets with greater speed and accuracy than NVGPs. This behavioral advantage was associated with an increased suppression of SSVEP amplitudes to unattended peripheral sequences in VGPs relative to NVGPs, whereas the magnitude of the attended SSVEPs was equivalent in the two groups. Group differences were also observed in the event-related potentials to targets in the alphanumeric sequences, with the target-elicited P300 component being of larger amplitude in VGPS than NVGPs. These electrophysiological findings suggest that the superior target detection capabilities of the VGPs are attributable, at least in part, to enhanced suppression of distracting irrelevant information and more effective perceptual decision processes.

Comparison of direct and heterodyne detection optical intersatellite communication links

NASA Technical Reports Server (NTRS)

Chen, C. C.; Gardner, C. S.

1987-01-01

The performance of direct and heterodyne detection optical intersatellite communication links are evaluated and compared. It is shown that the performance of optical links is very sensitive to the pointing and tracking errors at the transmitter and receiver. In the presence of random pointing and tracking errors, optimal antenna gains exist that will minimize the required transmitter power. In addition to limiting the antenna gains, random pointing and tracking errors also impose a power penalty in the link budget. This power penalty is between 1.6 to 3 dB for a direct detection QPPM link, and 3 to 5 dB for a heterodyne QFSK system. For the heterodyne systems, the carrier phase noise presents another major factor of performance degradation that must be considered. In contrast, the loss due to synchronization error is small. The link budgets for direct and heterodyne detection systems are evaluated. It is shown that, for systems with large pointing and tracking errors, the link budget is dominated by the spatial tracking error, and the direct detection system shows a superior performance because it is less sensitive to the spatial tracking error. On the other hand, for systems with small pointing and tracking jitters, the antenna gains are in general limited by the launch cost, and suboptimal antenna gains are often used in practice. In which case, the heterodyne system has a slightly higher power margin because of higher receiver sensitivity.

Tin Oxide Crystals Exposed by Low-Energy {110} Facets for Enhanced Electrochemical Heavy Metal Ions Sensing: X-ray Absorption Fine Structure Experimental Combined with Density-Functional Theory Evidence.

PubMed

Jin, Zhen; Yang, Meng; Chen, Shao-Hua; Liu, Jin-Huai; Li, Qun-Xiang; Huang, Xing-Jiu

2017-02-21

Herein, we revealed that the electrochemical behaviors on the detection of heavy metal ions (HMIs) would largely rely on the exposed facets of SnO 2 nanoparticles. Compared to the high-energy {221} facet, the low-energy {110} facet of SnO 2 possessed better electrochemical performance. The adsorption/desorption tests, density-functional theory (DFT) calculations, and X-ray absorption fine structure (XAFS) studies showed that the lower barrier energy of surface diffusion on {110} facet was critical for the superior electrochemical property, which was favorable for the ions diffusion on the electrode, and further leading the enhanced electrochemical performance. Through the combination of experiments and theoretical calculations, a reliable interpretation of the mechanism for electroanalysis of HMIs with nanomaterials exposed by different crystal facets has been provided. Furthermore, it provides a deep insight into understanding the key factor to improve the electrochemical performance for HMIs detection, so as to design high-performance electrochemical sensors.

Comparative study of label-free electrochemical immunoassay on various gold nanostructures

NASA Astrophysics Data System (ADS)

Rafique, S.; Gao, C.; Li, C. M.; Bhatti, A. S.

2013-10-01

Electrochemical methods such as amperometry and impedance spectroscopy provide the feasibility of label-free immunoassay. However, the performance of electrochemical interfaces varies with the shape of gold nanostructures. In the present work three types of gold nanostructures including pyramid, spherical, and rod-like nanostructures were electrochemically synthesized on the gold electrode and were further transformed into immunosensor by covalent binding of antibodies. As a model protein, a cancer biomarker, Carcinoembryonic Antigen (CEA) was detected using amperometric and impedimetric techniques on three nanostructured electrodes, which enabled to evaluate and compare the immunoassay's performance. It was found that all three immunosensors showed improved linear electrochemical response to the concentration of CEA compared to bare Au electrode. Among all the spherical gold nanostructure based immunosensors displayed superior performance. Under optimal condition, the immunosensors exhibited a limit of detection of 4.1 pg ml-1 over a concentration range of five orders of magnitude. This paper emphasizes that fine control over the geometry of nanostructures is essentially important for high-performance electrochemical immunoassay.

Serial nonenhancing magnetic resonance imaging scans of high grade glioblastoma multiforme.

PubMed Central

Moore-Stovall, J.; Venkatesh, R.

1993-01-01

Magnetic resonance imaging (MRI) from clinical experience has proven to be superior to all other diagnostic imaging modalities, including computed tomography (CT) in the detection of intracranial neoplasms. Although glioblastoma multiforme presents a challenge for all diagnostic imaging modalities including MRI, MRI is paramount to CT in detecting subtle abnormal water accumulation in brain tissue caused by tumor even before there is disruption of the blood brain barrier. Currently, clinical research and investigational trials on nonionic gadolinium contrast agents have proven that nonionic gadolinium HP-DO3A (ProHance) contrast agents have lower osmolality and greater stability, which make them superior compounds to gadolinium diethylenetriamine-pentacetic acid (Gd-DTPA). Therefore, the nonionic gadolinium contrasts have been safely administered more rapidly, in higher or multiple doses for contrast enhanced MRI without adverse side effects or changes in serum iron or total bilirubin, and the intensity of the area of enhancement and number of lesions detected were superior to that of Gd-DTPA (Magnevist) at the standard dose (0.1 mmol/Kg). Perhaps if the nonionic gadolinium contrast agent, ProHance, had been approved by the Food and Drug Administration (FDA) when this MRI was performed in 1990 it would have aided in providing contrast enhancement and visualization of the tumor lesion to assist in patient diagnosis and management. Magnetic resonance imaging also provides unique multiplanar capabilities that allow for optimal visualization of the temporal and occipital lobes of the brain without bone interference.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9A Figure 9B Figure 10 Figure 11 Figure 12 Figure 13 PMID:8382751

Performance effects of nicotine during selective attention, divided attention, and simple stimulus detection: an fMRI study.

PubMed

Hahn, Britta; Ross, Thomas J; Wolkenberg, Frank A; Shakleya, Diaa M; Huestis, Marilyn A; Stein, Elliot A

2009-09-01

Attention-enhancing effects of nicotine appear to depend on the nature of the attentional function. Underlying neuroanatomical mechanisms, too, may vary depending on the function modulated. This functional magnetic resonance imaging study recorded blood oxygen level-dependent (BOLD) activity in minimally deprived smokers during tasks of simple stimulus detection, selective attention, or divided attention after single-blind application of a transdermal nicotine (21 mg) or placebo patch. Smokers' performance in the placebo condition was unimpaired as compared with matched nonsmokers. Nicotine reduced reaction time (RT) in the stimulus detection and selective attention but not divided attention condition. Across all task conditions, nicotine reduced activation in frontal, temporal, thalamic, and visual regions and enhanced deactivation in so-called "default" regions. Thalamic effects correlated with RT reduction selectively during stimulus detection. An interaction with task condition was observed in middle and superior frontal gyri, where nicotine reduced activation only during stimulus detection. A visuomotor control experiment provided evidence against nonspecific effects of nicotine. In conclusion, although prefrontal activity partly displayed differential modulation by nicotine, most BOLD effects were identical across tasks, despite differential performance effects, suggesting that common neuronal mechanisms can selectively benefit different attentional functions. Overall, the effects of nicotine may be explained by increased functional efficiency and downregulated task-independent "default" functions.

LIMPIC: a computational method for the separation of protein MALDI-TOF-MS signals from noise.

PubMed

Mantini, Dante; Petrucci, Francesca; Pieragostino, Damiana; Del Boccio, Piero; Di Nicola, Marta; Di Ilio, Carmine; Federici, Giorgio; Sacchetta, Paolo; Comani, Silvia; Urbani, Andrea

2007-03-26

Mass spectrometry protein profiling is a promising tool for biomarker discovery in clinical proteomics. However, the development of a reliable approach for the separation of protein signals from noise is required. In this paper, LIMPIC, a computational method for the detection of protein peaks from linear-mode MALDI-TOF data is proposed. LIMPIC is based on novel techniques for background noise reduction and baseline removal. Peak detection is performed considering the presence of a non-homogeneous noise level in the mass spectrum. A comparison of the peaks collected from multiple spectra is used to classify them on the basis of a detection rate parameter, and hence to separate the protein signals from other disturbances. LIMPIC preprocessing proves to be superior than other classical preprocessing techniques, allowing for a reliable decomposition of the background noise and the baseline drift from the MALDI-TOF mass spectra. It provides lower coefficient of variation associated with the peak intensity, improving the reliability of the information that can be extracted from single spectra. Our results show that LIMPIC peak-picking is effective even in low protein concentration regimes. The analytical comparison with commercial and freeware peak-picking algorithms demonstrates its superior performances in terms of sensitivity and specificity, both on in-vitro purified protein samples and human plasma samples. The quantitative information on the peak intensity extracted with LIMPIC could be used for the recognition of significant protein profiles by means of advanced statistic tools: LIMPIC might be valuable in the perspective of biomarker discovery.

Automatic Constraint Detection for 2D Layout Regularization.

PubMed

Jiang, Haiyong; Nan, Liangliang; Yan, Dong-Ming; Dong, Weiming; Zhang, Xiaopeng; Wonka, Peter

2016-08-01

In this paper, we address the problem of constraint detection for layout regularization. The layout we consider is a set of two-dimensional elements where each element is represented by its bounding box. Layout regularization is important in digitizing plans or images, such as floor plans and facade images, and in the improvement of user-created contents, such as architectural drawings and slide layouts. To regularize a layout, we aim to improve the input by detecting and subsequently enforcing alignment, size, and distance constraints between layout elements. Similar to previous work, we formulate layout regularization as a quadratic programming problem. In addition, we propose a novel optimization algorithm that automatically detects constraints. We evaluate the proposed framework using a variety of input layouts from different applications. Our results demonstrate that our method has superior performance to the state of the art.

Aggregated channels network for real-time pedestrian detection

NASA Astrophysics Data System (ADS)

Ghorban, Farzin; Marín, Javier; Su, Yu; Colombo, Alessandro; Kummert, Anton

2018-04-01

Convolutional neural networks (CNNs) have demonstrated their superiority in numerous computer vision tasks, yet their computational cost results prohibitive for many real-time applications such as pedestrian detection which is usually performed on low-consumption hardware. In order to alleviate this drawback, most strategies focus on using a two-stage cascade approach. Essentially, in the first stage a fast method generates a significant but reduced amount of high quality proposals that later, in the second stage, are evaluated by the CNN. In this work, we propose a novel detection pipeline that further benefits from the two-stage cascade strategy. More concretely, the enriched and subsequently compressed features used in the first stage are reused as the CNN input. As a consequence, a simpler network architecture, adapted for such small input sizes, allows to achieve real-time performance and obtain results close to the state-of-the-art while running significantly faster without the use of GPU. In particular, considering that the proposed pipeline runs in frame rate, the achieved performance is highly competitive. We furthermore demonstrate that the proposed pipeline on itself can serve as an effective proposal generator.

Diagnosis of glaucoma and detection of glaucoma progression using spectral domain optical coherence tomography.

PubMed

Grewal, Dilraj S; Tanna, Angelo P

2013-03-01

With the rapid adoption of spectral domain optical coherence tomography (SDOCT) in clinical practice and the recent advances in software technology, there is a need for a review of the literature on glaucoma detection and progression analysis algorithms designed for the commercially available instruments. Peripapillary retinal nerve fiber layer (RNFL) thickness and macular thickness, including segmental macular thickness calculation algorithms, have been demonstrated to be repeatable and reproducible, and have a high degree of diagnostic sensitivity and specificity in discriminating between healthy and glaucomatous eyes across the glaucoma continuum. Newer software capabilities such as glaucoma progression detection algorithms provide an objective analysis of longitudinally obtained structural data that enhances our ability to detect glaucomatous progression. RNFL measurements obtained with SDOCT appear more sensitive than time domain OCT (TDOCT) for glaucoma progression detection; however, agreement with the assessments of visual field progression is poor. Over the last few years, several studies have been performed to assess the diagnostic performance of SDOCT structural imaging and its validity in assessing glaucoma progression. Most evidence suggests that SDOCT performs similarly to TDOCT for glaucoma diagnosis; however, SDOCT may be superior for the detection of early stage disease. With respect to progression detection, SDOCT represents an important technological advance because of its improved resolution and repeatability. Advancements in RNFL thickness quantification, segmental macular thickness calculation and progression detection algorithms, when used correctly, may help to improve our ability to diagnose and manage glaucoma.

Evaluation of outbreak detection performance using multi-stream syndromic surveillance for influenza-like illness in rural Hubei Province, China: a temporal simulation model based on healthcare-seeking behaviors.

PubMed

Fan, Yunzhou; Wang, Ying; Jiang, Hongbo; Yang, Wenwen; Yu, Miao; Yan, Weirong; Diwan, Vinod K; Xu, Biao; Dong, Hengjin; Palm, Lars; Nie, Shaofa

2014-01-01

Syndromic surveillance promotes the early detection of diseases outbreaks. Although syndromic surveillance has increased in developing countries, performance on outbreak detection, particularly in cases of multi-stream surveillance, has scarcely been evaluated in rural areas. This study introduces a temporal simulation model based on healthcare-seeking behaviors to evaluate the performance of multi-stream syndromic surveillance for influenza-like illness. Data were obtained in six towns of rural Hubei Province, China, from April 2012 to June 2013. A Susceptible-Exposed-Infectious-Recovered model generated 27 scenarios of simulated influenza A (H1N1) outbreaks, which were converted into corresponding simulated syndromic datasets through the healthcare-behaviors model. We then superimposed converted syndromic datasets onto the baselines obtained to create the testing datasets. Outbreak performance of single-stream surveillance of clinic visit, frequency of over the counter drug purchases, school absenteeism, and multi-stream surveillance of their combinations were evaluated using receiver operating characteristic curves and activity monitoring operation curves. In the six towns examined, clinic visit surveillance and school absenteeism surveillance exhibited superior performances of outbreak detection than over the counter drug purchase frequency surveillance; the performance of multi-stream surveillance was preferable to signal-stream surveillance, particularly at low specificity (Sp <90%). The temporal simulation model based on healthcare-seeking behaviors offers an accessible method for evaluating the performance of multi-stream surveillance.

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

Assessment of the GPM and TRMM Precipitation Products Using the Rain Gauge Network over the Tibetan Plateau

NASA Astrophysics Data System (ADS)

Zhang, Sijia; Wang, Donghai; Qin, Zhengkun; Zheng, Yaoyao; Guo, Jianping

2018-04-01

Using high-quality hourly observations from national-level ground-based stations, the satellite-based rainfall products from both the Global Precipitation Measurement (GPM) Integrated MultisatellitE Retrievals for GPM (IMERG) and its predecessor, the Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA), are statistically evaluated over the Tibetan Plateau (TP), with an emphasis on the diurnal variation. The results indicate that: (1) the half-hourly IMERG rainfall product can explicitly describe the diurnal variation over the TP, but with discrepancies in the timing of the greatest precipitation intensity and an overestimation of the maximum rainfall intensity over the whole TP. In addition, the performance of IMERG on the hourly timescale, in terms of the correlation coefficient and relative bias, is different for regions with sea level height below or above 3500 m; (2) the IMERG products, having higher correlation and lower root-mean-square error, perform better than the TMPA products on the daily and monthly timescales; and (3) the detection ability of IMERG is superior to that of TMPA, as corroborated by a higher Hanssen and Kuipers score, a higher probability of detection, a lower false alarm ratio, and a lower bias. Compared to TMPA, the IMERG products ameliorate the overestimation across the TP. In conclusion, GPM IMERG is superior to TRMM TMPA over the TP on multiple timescales.

Presence of selected chemicals of emerging concern in water and bottom sediment from the St. Louis River, St. Louis Bay, and Superior Bay, Minnesota and Wisconsin, 2010

USGS Publications Warehouse

Christensen, Victoria G.; Lee, Kathy E.; Kieta, Kristen A.; Elliott, Sarah M.

2012-01-01

The St. Louis Bay of Lake Superior receives substantial urban runoff, wastewater treatment plant effluent, and industrial effluent. In 1987, the International Joint Commission designated the St. Louis Bay portion of the lower St. Louis River as one of the Great Lakes Areas of Concern. Concerns exist about the potential effects of chemicals of emerging concern on aquatic biota because many of these chemicals, including endocrine active chemicals, have been shown to affect the endocrine systems of fish. To determine the occurrence of chemicals of emerging concern in the St. Louis River, the St. Louis Bay, and Superior Bay, the U.S. Geological Survey in cooperation with the Minnesota Pollution Control Agency and the Wisconsin Department of Natural Resources collected water and bottom-sediment samples from 40 sites from August through October 2010. The objectives of this study were to (1) identify the extent to which chemicals of emerging concern, including pharmaceuticals, hormones, and other organic chemicals, occur in the St. Louis River, St. Louis Bay, and Superior Bay, and (2) identify the extent to which the chemicals may have accumulated in bottom sediment of the study area. Samples were analyzed for selected wastewater indicators, hormones, sterols, bisphenol A, and human-health pharmaceuticals. During this study, 33 of 89 chemicals of emerging concern were detected among all water samples collected and 56 of 104 chemicals of emerging concern were detected in bottom-sediment samples. The chemical N,N-diethyl-meta-toluamide (DEET) was the most commonly detected chemical in water samples and 2,6-dimethylnaphthalene was the most commonly detected chemical in bottom-sediment samples. In general, chemicals of emerging concern were detected at a higher frequency in bottom-sediment samples than in water samples. Estrone (a steroid hormone) and hexahydrohexamethyl cyclopentabensopyran (a synthetic fragrance) were the most commonly detected endocrine active chemicals in water samples; beta-sitosterol (a plant sterol), estrone, and 4-tert-octylphenol (an alkylphenol) were the most commonly detected endocrine active chemicals in bottom-sediment samples. The greater detection frequency of chemicals in bottom-sediment samples compared to the detection frequency in water samples indicates that bottom sediment is an important sink for chemicals of emerging concern. At least one polycyclic aromatic hydrocarbon was detected in every sample; and in most samples, all nine polycyclic aromatic hydrocarbons included in analyses were detected. Bottom sediment collected from Superior Bay had the most polycyclic aromatic hydrocarbon detections of the sediment sampling locations.

Ultrasensitive, Real-time and Discriminative Detection of Improvised Explosives by Chemiresistive Thin-film Sensory Array of Mn2+ Tailored Hierarchical ZnS

NASA Astrophysics Data System (ADS)

Zhou, Chaoyu; Wu, Zhaofeng; Guo, Yanan; Li, Yushu; Cao, Hongyu; Zheng, Xuefang; Dou, Xincun

2016-05-01

A simple method combing Mn2+ doping with a hierarchical structure was developed for the improvement of thin-film sensors and efficient detection of the explosives relevant to improvised explosive devices (IEDs). ZnS hierarchical nanospheres (HNs) were prepared via a solution-based route and their sensing performances were manipulated by Mn2+ doping. The responses of the sensors based on ZnS HNs towards 8 explosives generally increase firstly and then decrease with the increase of the doped Mn2+ concentration, reaching the climate at 5% Mn2+. Furthermore, the sensory array based on ZnS HNs with different doping levels achieved the sensitive and discriminative detection of 6 analytes relevant to IEDs and 2 military explosives in less than 5 s at room temperature. Importantly, the superior sensing performances make ZnS HNs material interesting in the field of chemiresistive sensors, and this simple method could be a very promising strategy to put the sensors based on thin-films of one-dimensional (1D) nanostructures into practical IEDs detection.

The visual analysis of emotional actions.

PubMed

Chouchourelou, Arieta; Matsuka, Toshihiko; Harber, Kent; Shiffrar, Maggie

2006-01-01

Is the visual analysis of human actions modulated by the emotional content of those actions? This question is motivated by a consideration of the neuroanatomical connections between visual and emotional areas. Specifically, the superior temporal sulcus (STS), known to play a critical role in the visual detection of action, is extensively interconnected with the amygdala, a center for emotion processing. To the extent that amygdala activity influences STS activity, one would expect to find systematic differences in the visual detection of emotional actions. A series of psychophysical studies tested this prediction. Experiment 1 identified point-light walker movies that convincingly depicted five different emotional states: happiness, sadness, neutral, anger, and fear. In Experiment 2, participants performed a walker detection task with these movies. Detection performance was systematically modulated by the emotional content of the gaits. Participants demonstrated the greatest visual sensitivity to angry walkers. The results of Experiment 3 suggest that local velocity cues to anger may account for high false alarm rates to the presence of angry gaits. These results support the hypothesis that the visual analysis of human action depends upon emotion processes.

Ultrasensitive, Real-time and Discriminative Detection of Improvised Explosives by Chemiresistive Thin-film Sensory Array of Mn2+ Tailored Hierarchical ZnS

PubMed Central

Zhou, Chaoyu; Wu, Zhaofeng; Guo, Yanan; Li, Yushu; Cao, Hongyu; Zheng, Xuefang; Dou, Xincun

2016-01-01

A simple method combing Mn2+ doping with a hierarchical structure was developed for the improvement of thin-film sensors and efficient detection of the explosives relevant to improvised explosive devices (IEDs). ZnS hierarchical nanospheres (HNs) were prepared via a solution-based route and their sensing performances were manipulated by Mn2+ doping. The responses of the sensors based on ZnS HNs towards 8 explosives generally increase firstly and then decrease with the increase of the doped Mn2+ concentration, reaching the climate at 5% Mn2+. Furthermore, the sensory array based on ZnS HNs with different doping levels achieved the sensitive and discriminative detection of 6 analytes relevant to IEDs and 2 military explosives in less than 5 s at room temperature. Importantly, the superior sensing performances make ZnS HNs material interesting in the field of chemiresistive sensors, and this simple method could be a very promising strategy to put the sensors based on thin-films of one-dimensional (1D) nanostructures into practical IEDs detection. PMID:27161193

Sky light polarization detection with linear polarizer triplet in light field camera inspired by insect vision.

PubMed

Zhang, Wenjing; Cao, Yu; Zhang, Xuanzhe; Liu, Zejin

2015-10-20

Stable information of a sky light polarization pattern can be used for navigation with various advantages such as better performance of anti-interference, no "error cumulative effect," and so on. But the existing method of sky light polarization measurement is weak in real-time performance or with a complex system. Inspired by the navigational capability of a Cataglyphis with its compound eyes, we introduce a new approach to acquire the all-sky image under different polarization directions with one camera and without a rotating polarizer, so as to detect the polarization pattern across the full sky in a single snapshot. Our system is based on a handheld light field camera with a wide-angle lens and a triplet linear polarizer placed over its aperture stop. Experimental results agree with the theoretical predictions. Not only real-time detection but simple and costless architecture demonstrates the superiority of the approach proposed in this paper.

Sensitive Nonenzymatic Electrochemical Glucose Detection Based on Hollow Porous NiO

NASA Astrophysics Data System (ADS)

He, Gege; Tian, Liangliang; Cai, Yanhua; Wu, Shenping; Su, Yongyao; Yan, Hengqing; Pu, Wanrong; Zhang, Jinkun; Li, Lu

2018-01-01

Transition metal oxides (TMOs) have attracted extensive research attentions as promising electrocatalytic materials. Despite low cost and high stability, the electrocatalytic activity of TMOs still cannot satisfy the requirements of applications. Inspired by kinetics, the design of hollow porous structure is considered as a promising strategy to achieve superior electrocatalytic performance. In this work, cubic NiO hollow porous architecture (NiO HPA) was constructed through coordinating etching and precipitating (CEP) principle followed by post calcination. Being employed to detect glucose, NiO HPA electrode exhibits outstanding electrocatalytic activity in terms of high sensitivity (1323 μA mM-1 cm-2) and low detection limit (0.32 μM). The excellent electrocatalytic activity can be ascribed to large specific surface area (SSA), ordered diffusion channels, and accelerated electron transfer rate derived from the unique hollow porous features. The results demonstrate that the NiO HPA could have practical applications in the design of nonenzymatic glucose sensors. The construction of hollow porous architecture provides an effective nanoengineering strategy for high-performance electrocatalysts.

Trace determination of thiram using SERS-active hollow sea-urchin gold nanoparticles

NASA Astrophysics Data System (ADS)

Zhang, Guanghui; Zhang, Chuankun; Ma, Yanan; Wang, Zheng; Wang, Shun; Xu, Chan; Wang, Dashuang

2017-04-01

Surface-enhanced Raman scattering (SERS) is greatly structure-dependent on the absorbed nanoparticles. Nanostructures with different novel morphologies show different Raman enhancement factor orders of magnitude. Herein, a unique nanostructure with fruitful SERS-active sites, composed of hollow interiors and thorns which named as hollow sea-urchin gold nanoparticles (HSU-GNPs), was synthesized by using a one-pot galvanic replacement method. And the corresponding morphologies and optical properties were characterized by TEM images and absorption spectra. Importantly, the synthetic parameters of HSU-GNPs were optimized to obtain a superior SERS performance by analyzing the formation mechanism and the SERS spectra of R6G-labeled HSU-GNPs which obtained at different concentrations of AgNO3. Furthermore, the SERS-based application of HSU-GNPs was performed on the dose-response detection of thiram. The experimental result shows this detection strategy is available for thiram with decent sensitivity and reproducibility, which suggests that it is an excellent candidate for the detection of pesticides.

Train axle bearing fault detection using a feature selection scheme based multi-scale morphological filter

NASA Astrophysics Data System (ADS)

Li, Yifan; Liang, Xihui; Lin, Jianhui; Chen, Yuejian; Liu, Jianxin

2018-02-01

This paper presents a novel signal processing scheme, feature selection based multi-scale morphological filter (MMF), for train axle bearing fault detection. In this scheme, more than 30 feature indicators of vibration signals are calculated for axle bearings with different conditions and the features which can reflect fault characteristics more effectively and representatively are selected using the max-relevance and min-redundancy principle. Then, a filtering scale selection approach for MMF based on feature selection and grey relational analysis is proposed. The feature selection based MMF method is tested on diagnosis of artificially created damages of rolling bearings of railway trains. Experimental results show that the proposed method has a superior performance in extracting fault features of defective train axle bearings. In addition, comparisons are performed with the kurtosis criterion based MMF and the spectral kurtosis criterion based MMF. The proposed feature selection based MMF method outperforms these two methods in detection of train axle bearing faults.

Electrochemical sensor for rutin detection based on Au nanoparticle-loaded helical carbon nanotubes

NASA Astrophysics Data System (ADS)

Yang, Haitang; Li, Bingyue; Cui, Rongjing; Xing, Ruimin; Liu, Shanhu

2017-10-01

The key step in the fabrication of highly active electrochemical sensors is seeking multifunctional nanocomposites as electrode modified materials. In this study, the gold nanoparticle-decorated helical carbon nanotube nanocomposites (AuNPs-HCNTs) were fabricated for rutin detection because of its superior sensitivity, the chemical stability of AuNPs, and the superior conductivity and unique 3D-helical structure of helical carbon nanotubes. Results showed the prepared nanocomposites exhibited superior electrocatalytic activity towards rutin due to the synergetic effects of AuNPs and HCNTs. Under the optimized conditions, the developed sensor exhibited a linear response range from 0.1 to 31 μmol/L for rutin with a low detectable limit of 81 nmol/L. The proposed method might offer a possibility for electrochemical analysis of rutin in Chinese medical analysis or serum monitoring owing to its low cost, simplicity, high sensitivity, good stability, and few interferences against common coexisting ions in real samples.

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

Cross-sectional echocardiographic diagnosis of systemic venous return.

PubMed Central

Huhta, J C; Smallhorn, J F; Macartney, F J; Anderson, R H; de Leval, M

1982-01-01

To determine the sensitivity and specificity of cross-sectional echocardiography in diagnosing anomalous systemic venous return we used the technique in 800 consecutive children with congenital heart disease and whom the diagnosis was ultimately confirmed by angiography. Cross-sectional echocardiography was performed without prior knowledge of the diagnosis in all but 11 patients, who were recalled because of a known abnormality of atrial situs. The sensitivity of cross-sectional echocardiographic detection of various structures was as follows: right superior vena cava 792/792 (100%); left superior vena cava 46/48 (96%); bilateral superior vena cava 38/40 (95%); bridging innominate vein with bilateral superior vena cava 13/18 (72%); connection of superior caval segment to heart (coronary sinus or either atrium) (100%); absence of suprarenal inferior vena cava 23/23 (100%); azygos continuation of the inferior vena cava 31/33 (91%); downstream connection of azygos continuation, once seen, 21/21 (100%); partial anomalous hepatic venous connection (one hepatic vein not connected to the inferior vena cava) 1/1 (100%); total anomalous hepatic venous connection (invariably associated with left isomerism) 23/23 (100%). The specificity of each above diagnoses was 100% except in one infant with exomphalos in whom absence of the suprarenal inferior vena cava was incorrectly diagnosed. Thus cross-sectional echocardiography is an extremely specific and highly sensitive method of recognizing anomalous systemic venous return. It is therefore of great value of planning both cardiac catheterisation and cannulation for open heart surgery. Images PMID:6751361

Detection of exudates in fundus imagery using a constant false-alarm rate (CFAR) detector

NASA Astrophysics Data System (ADS)

Khanna, Manish; Kapoor, Elina

2014-05-01

Diabetic retinopathy is the leading cause of blindness in adults in the United States. The presence of exudates in fundus imagery is the early sign of diabetic retinopathy so detection of these lesions is essential in preventing further ocular damage. In this paper we present a novel technique to automatically detect exudates in fundus imagery that is robust against spatial and temporal variations of background noise. The detection threshold is adjusted dynamically, based on the local noise statics around the pixel under test in order to maintain a pre-determined, constant false alarm rate (CFAR). The CFAR detector is often used to detect bright targets in radar imagery where the background clutter can vary considerably from scene to scene and with angle to the scene. Similarly, the CFAR detector addresses the challenge of detecting exudate lesions in RGB and multispectral fundus imagery where the background clutter often exhibits variations in brightness and texture. These variations present a challenge to common, global thresholding detection algorithms and other methods. Performance of the CFAR algorithm is tested against a publicly available, annotated, diabetic retinopathy database and preliminary testing suggests that performance of the CFAR detector proves to be superior to techniques such as Otsu thresholding.

Contrast-enhanced spectral mammography vs. mammography and MRI - clinical performance in a multi-reader evaluation.

PubMed

Fallenberg, Eva M; Schmitzberger, Florian F; Amer, Heba; Ingold-Heppner, Barbara; Balleyguier, Corinne; Diekmann, Felix; Engelken, Florian; Mann, Ritse M; Renz, Diane M; Bick, Ulrich; Hamm, Bernd; Dromain, Clarisse

2017-07-01

To compare the diagnostic performance of contrast-enhanced spectral mammography (CESM) to digital mammography (MG) and magnetic resonance imaging (MRI) in a prospective two-centre, multi-reader study. One hundred seventy-eight women (mean age 53 years) with invasive breast cancer and/or DCIS were included after ethics board approval. MG, CESM and CESM + MG were evaluated by three blinded radiologists based on amended ACR BI-RADS criteria. MRI was assessed by another group of three readers. Receiver-operating characteristic (ROC) curves were compared. Size measurements for the 70 lesions detected by all readers in each modality were correlated with pathology. Reading results for 604 lesions were available (273 malignant, 4 high-risk, 327 benign). The area under the ROC curve was significantly larger for CESM alone (0.84) and CESM + MG (0.83) compared to MG (0.76) (largest advantage in dense breasts) while it was not significantly different from MRI (0.85). Pearson correlation coefficients for size comparison were 0.61 for MG, 0.69 for CESM, 0.70 for CESM + MG and 0.79 for MRI. This study showed that CESM, alone and in combination with MG, is as accurate as MRI but is superior to MG for lesion detection. Patients with dense breasts benefitted most from CESM with the smallest additional dose compared to MG. • CESM has comparable diagnostic performance (ROC-AUC) to MRI for breast cancer diagnostics. • CESM in combination with MG does not improve diagnostic performance. • CESM has lower sensitivity but higher specificity than MRI. • Sensitivity differences are more pronounced in dense and not significant in non-dense breasts. • CESM and MRI are significantly superior to MG, particularly in dense breasts.

Determining the Performance of Fluorescence Molecular Imaging Devices using Traceable Working Standards with SI Units of Radiance

PubMed Central

Zhu, Banghe; Rasmussen, John C.; Litorja, Maritoni

2017-01-01

To date, no emerging preclinical or clinical near-infrared fluorescence (NIRF) imaging devices for non-invasive and/or surgical guidance have their performances validated on working standards with SI units of radiance that enable comparison or quantitative quality assurance. In this work, we developed and deployed a methodology to calibrate a stable, solid phantom for emission radiance with units of mW · sr−1 · cm−2 for use in characterizing the measurement sensitivity of ICCD and IsCMOS detection, signal-to-noise ratio, and contrast. In addition, at calibrated radiances, we assess transverse and lateral resolution of ICCD and IsCMOS camera systems. The methodology allowed determination of superior SNR of the ICCD over the IsCMOS camera system and superior resolution of the IsCMOS over the ICCD camera system. Contrast depended upon the camera settings (binning and integration time) and gain of intensifier. Finally, because of architecture of CMOS and CCD camera systems resulting in vastly different performance, we comment on the utility of these systems for small animal imaging as well as clinical applications for non-invasive and surgical guidance. PMID:26552078

Fabrication and characteristics of high-performance and high-stability aluminum-doped zinc oxide thin-film transistors

NASA Astrophysics Data System (ADS)

Shan, Dongfang; Han, Dedong; Huang, Fuqing; Tian, Yu; Zhang, Suoming; Qi, Lin; Cong, Yingying; Zhang, Shengdong; Zhang, Xing; Wang, Yi

2014-01-01

Fully transparent aluminum-doped zinc oxide (AZO) thin-film transistors (TFTs) were successfully fabricated on glass substrates at room temperature. Superior properties, such as a high saturation mobility of 59.3 cm2 V-1 s-1, a positive threshold voltage of 1.3 V, a steep subthreshold swing of 122.9 mV/dec, an off-state current on the order of 10-12 A, and an on/off ratio of 2.7 × 108, were obtained. The electrical properties of the AZO TFTs were successively studied within a period of six months. Small property degenerations could be observed from the test results obtained within the study period, which proved the high-performance and high-stability characteristics of AZO TFTs. Furthermore, hysteresis loop scanning of AZO TFTs was performed, and a small hysteresis could be detected in the scanning curves, which suggested the superior properties of a dielectric and a channel-insulator interface. Lastly, we succeeded in manufacturing an organic LED (OLED) flat panel display panel driven by AZO TFTs and obtained an excellent display effect from it. We believe that AZO TFTs are a promising candidate successor to Si-based TFTs in next-generation flat panel displays.

A morphometric analysis of the superior cervical ganglion and its surrounding structures.

PubMed

Fazliogullari, Zeliha; Kilic, Cenk; Karabulut, Ahmet Kagan; Yazar, Fatih

2016-04-01

The aim of this cadaveric study was to detect the superior cervical ganglion (SCG) in a topographic manner according to vertebrae and to determine the relationship between the vertebrae, mandibular angle and longus colli muscle through morphometric analysis. The present study was performed on 40 SCG of 20 human cadavers (16 males, 4 females). The level of the SCG was determined based on the vertebrae. Ganglion length, width and thickness were detected. Distance to the adjacent vertebra, the mandibular angle and medial side of the longus colli muscle were measured. The results were evaluated statistically. The SCG existing in all cadavers was detected at the C2 vertebra level in 34 cadavers and at the C3 vertebra level in 6 cadavers. The average length, width and thickness of the SCG were 15.18 ± 1.12, 4.62 ± 0.25, and 1.83 ± 0.10 mm, respectively. No statistically significant difference was detected in terms of the distances between the ganglion and anterior tubercle of transverse processes of the vertebrae as well as the mandibular angle on either side. The distance between the SCG and the medial edge of the longus colli muscle was significantly greater on the left side in both men (p < 0.001) and women (p < 0.01). Recognition of morphometric characteristics of the SCG and detection of its location according to adjacent formations may serve as a guide for nerve blockage studies and help surgeons to preserve the ganglion in both anterior and anterolateral cervical approaches.

Application of a Multiplex Quantitative PCR to Assess Prevalence and Intensity Of Intestinal Parasite Infections in a Controlled Clinical Trial

PubMed Central

Llewellyn, Stacey; Inpankaew, Tawin; Nery, Susana Vaz; Gray, Darren J.; Verweij, Jaco J.; Clements, Archie C. A.; Gomes, Santina J.; Traub, Rebecca; McCarthy, James S.

2016-01-01

Background Accurate quantitative assessment of infection with soil transmitted helminths and protozoa is key to the interpretation of epidemiologic studies of these parasites, as well as for monitoring large scale treatment efficacy and effectiveness studies. As morbidity and transmission of helminth infections are directly related to both the prevalence and intensity of infection, there is particular need for improved techniques for assessment of infection intensity for both purposes. The current study aimed to evaluate two multiplex PCR assays to determine prevalence and intensity of intestinal parasite infections, and compare them to standard microscopy. Methodology/Principal Findings Faecal samples were collected from a total of 680 people, originating from rural communities in Timor-Leste (467 samples) and Cambodia (213 samples). DNA was extracted from stool samples and subject to two multiplex real-time PCR reactions the first targeting: Necator americanus, Ancylostoma spp., Ascaris spp., and Trichuris trichiura; and the second Entamoeba histolytica, Cryptosporidium spp., Giardia. duodenalis, and Strongyloides stercoralis. Samples were also subject to sodium nitrate flotation for identification and quantification of STH eggs, and zinc sulphate centrifugal flotation for detection of protozoan parasites. Higher parasite prevalence was detected by multiplex PCR (hookworms 2.9 times higher, Ascaris 1.2, Giardia 1.6, along with superior polyparasitism detection with this effect magnified as the number of parasites present increased (one: 40.2% vs. 38.1%, two: 30.9% vs. 12.9%, three: 7.6% vs. 0.4%, four: 0.4% vs. 0%). Although, all STH positive samples were low intensity infections by microscopy as defined by WHO guidelines the DNA-load detected by multiplex PCR suggested higher intensity infections. Conclusions/Significance Multiplex PCR, in addition to superior sensitivity, enabled more accurate determination of infection intensity for Ascaris, hookworms and Giardia compared to microscopy, especially in samples exhibiting polyparasitism. The superior performance of multiplex PCR to detect polyparasitism and more accurately determine infection intensity suggests that it is a more appropriate technique for use in epidemiologic studies and for monitoring large-scale intervention trials. PMID:26820626

Natural history of Leber's hereditary optic neuropathy: longitudinal analysis of the retinal nerve fiber layer by optical coherence tomography.

PubMed

Barboni, Piero; Carbonelli, Michele; Savini, Giacomo; Ramos, Carolina do V F; Carta, Arturo; Berezovsky, Adriana; Salomao, Solange R; Carelli, Valerio; Sadun, Alfredo A

2010-03-01

To investigate by optical coherence tomography (OCT) the topographic pattern and temporal sequence of fiber loss in the peripapillary retinal nerve fiber layer (RNFL) of patients with Leber's hereditary optic neuropathy (LHON) in a longitudinal follow-up. Cohort study. Six eyes of 4 patients with molecularly defined LHON were enrolled before the subacute period of visual loss. Subjects were studied by StratusOCT (Carl Zeiss Meditec, Inc., Dublin, CA) during a 9-month follow-up starting from the presymptomatic stage of the disease. Examinations were carried out at 4 different time points: presymptomatic stage, time of visual loss, and 3 and 9 months later. Peripapillary RNFL thickness for each quadrant of the optic nerve. Statistical comparisons were performed by ordinary analysis of variance with Dunnett's post-test. A significant increase of RNFL thickness was detected in the temporal and inferior quadrants between the presymptomatic stage and the disease onset (P<0.05). The 360-degree average and the superior and nasal quadrants showed a nonstatistically significant increase of thickness at this time. In the 360-degree average (P<0.01), superior (P<0.01), nasal (P<0.05), and inferior (P<0.01) quadrants, RNFL thickening showed statistically significant changes between the presymptomatic stage and the 3-month follow-up. At 3 months, a nonsignificant reduction of RNFL thickness was detected in the temporal quadrant. A significant reduction of RNFL was detected in all but the nasal quadrants between the presymptomatic stage and the 9-month Follow-up. The RNFL thickness increase first appeared at the temporal and inferior quadrants. Conversely, at 3 months the thickening fibers were more evident in the superior and nasal quadrants. These findings are consistent with the established preferential early involvement of the papillomacular bundle in LHON. We also demonstrated the previously unrecognized simultaneous early involvement of the inferior quadrant. The late involvement of both superior and nasal quadrants suggests a dynamic evolution of the acute stage that continues for 3 months and may represent a therapeutic window of opportunity. Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Addressing multi-label imbalance problem of surgical tool detection using CNN.

PubMed

Sahu, Manish; Mukhopadhyay, Anirban; Szengel, Angelika; Zachow, Stefan

2017-06-01

A fully automated surgical tool detection framework is proposed for endoscopic video streams. State-of-the-art surgical tool detection methods rely on supervised one-vs-all or multi-class classification techniques, completely ignoring the co-occurrence relationship of the tools and the associated class imbalance. In this paper, we formulate tool detection as a multi-label classification task where tool co-occurrences are treated as separate classes. In addition, imbalance on tool co-occurrences is analyzed and stratification techniques are employed to address the imbalance during convolutional neural network (CNN) training. Moreover, temporal smoothing is introduced as an online post-processing step to enhance runtime prediction. Quantitative analysis is performed on the M2CAI16 tool detection dataset to highlight the importance of stratification, temporal smoothing and the overall framework for tool detection. The analysis on tool imbalance, backed by the empirical results, indicates the need and superiority of the proposed framework over state-of-the-art techniques.

A COMPARATIVE STUDY OF REAL-TIME AND STATIC ULTRASONOGRAPHY DIAGNOSES FOR THE INCIDENTAL DETECTION OF DIFFUSE THYROID DISEASE.

PubMed

Kim, Dong Wook

2015-08-01

The aim of this study was to compare the diagnostic accuracy of real-time and static ultrasonography (US) for the incidental detection of diffuse thyroid disease (DTD). In 118 consecutive patients, a single radiologist performed real-time US before thyroidectomy. For static US, the same radiologist retrospectively investigated the sonographic findings on a picture-archiving and communication system after 3 months. The diagnostic categories of both real-time and static US diagnoses were determined based on the number of abnormal findings, and the diagnostic indices were calculated by a receiver operating characteristic (ROC) curve analysis using the histopathologic results as the reference standard. Histopathologic results included normal thyroid (n = 77), Hashimoto thyroiditis (n = 11), non-Hashimoto lymphocytic thyroiditis (n = 29), and diffuse hyperplasia (n = 1). Normal thyroid and DTD showed significant differences in echogenicity, echotexture, glandular margin, and vascularity on both real-time and static US. There was a positive correlation between US categories and histopathologic results in both real-time and static US. The highest diagnostic indices were obtained when the cutoff criteria of real-time and static US diagnoses were chosen as indeterminate and suspicious for DTD, respectively. The ROC curve analysis showed that real-time US was superior to static US in diagnostic accuracy. Both real-time and static US may be helpful for the detection of incidental DTD, but real-time US is superior to static US for detecting incidental DTD.

Fast learning method for convolutional neural networks using extreme learning machine and its application to lane detection.

PubMed

Kim, Jihun; Kim, Jonghong; Jang, Gil-Jin; Lee, Minho

2017-03-01

Deep learning has received significant attention recently as a promising solution to many problems in the area of artificial intelligence. Among several deep learning architectures, convolutional neural networks (CNNs) demonstrate superior performance when compared to other machine learning methods in the applications of object detection and recognition. We use a CNN for image enhancement and the detection of driving lanes on motorways. In general, the process of lane detection consists of edge extraction and line detection. A CNN can be used to enhance the input images before lane detection by excluding noise and obstacles that are irrelevant to the edge detection result. However, training conventional CNNs requires considerable computation and a big dataset. Therefore, we suggest a new learning algorithm for CNNs using an extreme learning machine (ELM). The ELM is a fast learning method used to calculate network weights between output and hidden layers in a single iteration and thus, can dramatically reduce learning time while producing accurate results with minimal training data. A conventional ELM can be applied to networks with a single hidden layer; as such, we propose a stacked ELM architecture in the CNN framework. Further, we modify the backpropagation algorithm to find the targets of hidden layers and effectively learn network weights while maintaining performance. Experimental results confirm that the proposed method is effective in reducing learning time and improving performance. Copyright © 2016 Elsevier Ltd. All rights reserved.

A new technique for detecting colored macro plastic debris on beaches using webcam images and CIELUV.

PubMed

Kataoka, Tomoya; Hinata, Hirofumi; Kako, Shin'ichiro

2012-09-01

We have developed a technique for detecting the pixels of colored macro plastic debris (plastic pixels) using photographs taken by a webcam installed on Sodenohama beach, Tobishima Island, Japan. The technique involves generating color references using a uniform color space (CIELUV) to detect plastic pixels and removing misdetected pixels by applying a composite image method. This technique demonstrated superior performance in terms of detecting plastic pixels of various colors compared to the previous method which used the lightness values in the CIELUV color space. We also obtained a 10-month time series of the quantity of plastic debris by combining a projective transformation with this technique. By sequential monitoring of plastic debris quantity using webcams, it is possible to clean up beaches systematically, to clarify the transportation processes of plastic debris in oceans and coastal seas and to estimate accumulation rates on beaches. Copyright © 2012 Elsevier Ltd. All rights reserved.

Fusion and Gaussian mixture based classifiers for SONAR data

NASA Astrophysics Data System (ADS)

Kotari, Vikas; Chang, KC

2011-06-01

Underwater mines are inexpensive and highly effective weapons. They are difficult to detect and classify. Hence detection and classification of underwater mines is essential for the safety of naval vessels. This necessitates a formulation of highly efficient classifiers and detection techniques. Current techniques primarily focus on signals from one source. Data fusion is known to increase the accuracy of detection and classification. In this paper, we formulated a fusion-based classifier and a Gaussian mixture model (GMM) based classifier for classification of underwater mines. The emphasis has been on sound navigation and ranging (SONAR) signals due to their extensive use in current naval operations. The classifiers have been tested on real SONAR data obtained from University of California Irvine (UCI) repository. The performance of both GMM based classifier and fusion based classifier clearly demonstrate their superior classification accuracy over conventional single source cases and validate our approach.

Magnetic Enzymatic Platform for Organophosphate Pesticide Detection Using Boron-doped Diamond Electrodes.

PubMed

Pino, Flavio; Ivandini, Tribidasari A; Nakata, Kazuya; Fujishima, Akira; Merkoçi, Arben; Einaga, Yasuaki

2015-01-01

A simple and reliable enzymatic system for organophosporus pesticide detection was successfully developed, by exploiting the synergy between the magnetic beads collection capacity and the outstanding electrochemistry property of boron-doped diamond electrodes. The determination of an organophosphate pesticide, chlorpyrifos (CPF), was performed based on the inhibition system of the enzyme acetylcholinesterase bonded to magnetic beads through a biotin-streptavidin complex system. A better sensitivity was found for a system with magnetic beads in the concentration range of 10(-9) to 10(-5) M. The estimated limits of detection based on IC10 (10% acetylcholinesterase (AChE) inhibition) have been detected and optimized to be 5.7 × 10(-10) M CPF. Spiked samples of water of Yokohama (Japan) have been measured to validate the efficiency of the enzymatic system. The results suggested that the use of magnetic beads to immobilize biomolecules or biosensing agents is suitable to maintain the superiority of BDD electrodes.

Reflection symmetry detection using locally affine invariant edge correspondence.

PubMed

Wang, Zhaozhong; Tang, Zesheng; Zhang, Xiao

2015-04-01

Reflection symmetry detection receives increasing attentions in recent years. The state-of-the-art algorithms mainly use the matching of intensity-based features (such as the SIFT) within a single image to find symmetry axes. This paper proposes a novel approach by establishing the correspondence of locally affine invariant edge-based features, which are superior to the intensity based in the aspects that it is insensitive to illumination variations, and applicable to textureless objects. The locally affine invariance is achieved by simple linear algebra for efficient and robust computations, making the algorithm suitable for detections under object distortions like perspective projection. Commonly used edge detectors and a voting process are, respectively, used before and after the edge description and matching steps to form a complete reflection detection pipeline. Experiments are performed using synthetic and real-world images with both multiple and single reflection symmetry axis. The test results are compared with existing algorithms to validate the proposed method.

Development of Highly Sensitive Bulk Acoustic Wave Device Biosensor Arrays for Screening and Early Detection of Prostate Cancer

DTIC Science & Technology

2008-01-01

phase biosensor. Zinc oxide (ZnO) yielded results far superior to the tantalum pentoxide ( Ta2O5 ) alternative that was attempted. Preliminary results...secondary crosslinking with GMBS was performed for ZnO surfaces coated with MTS and MPA. To provide visual confirmation of the density and uniformity of...contained 8 devices coated with the same antibody species. Fluoroscein Isothyocyanate (FITC) was selected as the negative control since FITC is a

Brain MRI analysis for Alzheimer's disease diagnosis using an ensemble system of deep convolutional neural networks.

PubMed

Islam, Jyoti; Zhang, Yanqing

2018-05-31

Alzheimer's disease is an incurable, progressive neurological brain disorder. Earlier detection of Alzheimer's disease can help with proper treatment and prevent brain tissue damage. Several statistical and machine learning models have been exploited by researchers for Alzheimer's disease diagnosis. Analyzing magnetic resonance imaging (MRI) is a common practice for Alzheimer's disease diagnosis in clinical research. Detection of Alzheimer's disease is exacting due to the similarity in Alzheimer's disease MRI data and standard healthy MRI data of older people. Recently, advanced deep learning techniques have successfully demonstrated human-level performance in numerous fields including medical image analysis. We propose a deep convolutional neural network for Alzheimer's disease diagnosis using brain MRI data analysis. While most of the existing approaches perform binary classification, our model can identify different stages of Alzheimer's disease and obtains superior performance for early-stage diagnosis. We conducted ample experiments to demonstrate that our proposed model outperformed comparative baselines on the Open Access Series of Imaging Studies dataset.

Quantification of signal detection performance degradation induced by phase-retrieval in propagation-based x-ray phase-contrast imaging

NASA Astrophysics Data System (ADS)

Chou, Cheng-Ying; Anastasio, Mark A.

2016-04-01

In propagation-based X-ray phase-contrast (PB XPC) imaging, the measured image contains a mixture of absorption- and phase-contrast. To obtain separate images of the projected absorption and phase (i.e., refractive) properties of a sample, phase retrieval methods can be employed. It has been suggested that phase-retrieval can always improve image quality in PB XPC imaging. However, when objective (task-based) measures of image quality are employed, this is not necessarily true and phase retrieval can be detrimental. In this work, signal detection theory is utilized to quantify the performance of a Hotelling observer (HO) for detecting a known signal in a known background. Two cases are considered. In the first case, the HO acts directly on the measured intensity data. In the second case, the HO acts on either the retrieved phase or absorption image. We demonstrate that the performance of the HO is superior when acting on the measured intensity data. The loss of task-specific information induced by phase-retrieval is quantified by computing the efficiency of the HO as the ratio of the test statistic signal-to-noise ratio (SNR) for the two cases. The effect of the system geometry on this efficiency is systematically investigated. Our findings confirm that phase-retrieval can impair signal detection performance in XPC imaging.

Adaptive Self-Tuning Networks

NASA Astrophysics Data System (ADS)

Knox, H. A.; Draelos, T.; Young, C. J.; Lawry, B.; Chael, E. P.; Faust, A.; Peterson, M. G.

2015-12-01

The quality of automatic detections from seismic sensor networks depends on a large number of data processing parameters that interact in complex ways. The largely manual process of identifying effective parameters is painstaking and does not guarantee that the resulting controls are the optimal configuration settings. Yet, achieving superior automatic detection of seismic events is closely related to these parameters. We present an automated sensor tuning (AST) system that learns near-optimal parameter settings for each event type using neuro-dynamic programming (reinforcement learning) trained with historic data. AST learns to test the raw signal against all event-settings and automatically self-tunes to an emerging event in real-time. The overall goal is to reduce the number of missed legitimate event detections and the number of false event detections. Reducing false alarms early in the seismic pipeline processing will have a significant impact on this goal. Applicable both for existing sensor performance boosting and new sensor deployment, this system provides an important new method to automatically tune complex remote sensing systems. Systems tuned in this way will achieve better performance than is currently possible by manual tuning, and with much less time and effort devoted to the tuning process. With ground truth on detections in seismic waveforms from a network of stations, we show that AST increases the probability of detection while decreasing false alarms.

Cochlear implant in Hong Kong Cantonese.

PubMed

Tang, S O; Luk, W S; Lau, C C; So, K W; Wong, C M; Yiu, M L; Kwok, C L

1990-11-01

Cochlear implant surgery was performed in four Cantonese-speaking postlingually deaf Chinese adults, using the House/3M single channel device. This article outlines the methodology, including preoperative assessment and postoperative rehabilitation; and explains the necessary modifications in speech and audiologic work-up in Cantonese-speaking patients. Salient features of Cantonese phonetics, especially its tonal characteristics, are described. The findings of the study are presented. The results of the cochlear implant would suggest a performance superior to that of the hearing aid. Furthermore, the cochlear implant is able to detect tonal cues. This quality of the cochlear implant may prove to be a valuable asset to a tonal language-speaking cochlear implantee.

GryphSens: A Smartphone-Based Portable Diagnostic Reader for the Rapid Detection of Progesterone in Milk

PubMed Central

Jang, Hyunwook; Ahmed, Syed Rahin; Neethirajan, Suresh

2017-01-01

Enzyme-linked immunosorbent assay (ELISA) is a popular assay technique for the detection and quantification of various biological substances due its high sensitivity and specificity. More often, it requires large and expensive laboratory instruments, which makes it difficult to conduct when the tests must be performed quickly at the point-of-care (POC). To increase portability and ease of use, we propose a portable diagnostic system based on a Raspberry Pi imaging sensor for the rapid detection of progesterone in milk samples. We designed, assembled, and tested a standalone portable diagnostic reader and validated it for progesterone detection against a standard ELISA assay using a commercial plate reader. The portable POC device yielded consistent results, regardless of differences in the cameras and flashlights between various smartphone devices. An Android application was built to provide front-end access to users, control the diagnostic reader, and display and store the progesterone measurement on the smartphone. The diagnostic reader takes images of the samples, reads the pixel values, processes the results, and presents the results on the handheld device. The proposed POC reader can perform to superior levels of performance as a plate reader, while adding the desirable qualities of portability and ease of use. PMID:28489036

GryphSens: A Smartphone-Based Portable Diagnostic Reader for the Rapid Detection of Progesterone in Milk.

PubMed

Jang, Hyunwook; Ahmed, Syed Rahin; Neethirajan, Suresh

2017-05-10

Enzyme-linked immunosorbent assay (ELISA) is a popular assay technique for the detection and quantification of various biological substances due its high sensitivity and specificity. More often, it requires large and expensive laboratory instruments, which makes it difficult to conduct when the tests must be performed quickly at the point-of-care (POC). To increase portability and ease of use, we propose a portable diagnostic system based on a Raspberry Pi imaging sensor for the rapid detection of progesterone in milk samples. We designed, assembled, and tested a standalone portable diagnostic reader and validated it for progesterone detection against a standard ELISA assay using a commercial plate reader. The portable POC device yielded consistent results, regardless of differences in the cameras and flashlights between various smartphone devices. An Android application was built to provide front-end access to users, control the diagnostic reader, and display and store the progesterone measurement on the smartphone. The diagnostic reader takes images of the samples, reads the pixel values, processes the results, and presents the results on the handheld device. The proposed POC reader can perform to superior levels of performance as a plate reader, while adding the desirable qualities of portability and ease of use.

Noise and range considerations for close-range radar sensing of life signs underwater.

PubMed

Hafner, Noah; Lubecke, Victor

2011-01-01

Close-range underwater sensing of motion-based life signs can be performed with low power Doppler radar and ultrasound techniques. Corresponding noise and range performance trade-offs are examined here, with regard to choice of frequency and technology. The frequency range examined includes part of the UHF and microwave spectrum. Underwater detection of motion by radar in freshwater and saltwater are demonstrated. Radar measurements exhibited reduced susceptibility to noise as compared to ultrasound. While higher frequency radar exhibited better signal to noise ratio, propagation was superior for lower frequencies. Radar detection of motion through saltwater was also demonstrated at restricted ranges (1-2 cm) with low power transmission (10 dBm). The results facilitate the establishment of guidelines for optimal choice in technology for the underwater measurement motion-based life signs, with respect to trade offs involving range and noise.

Electrochemical biosensing of galactose based on carbon materials: graphene versus multi-walled carbon nanotubes.

PubMed

Dalkıran, Berna; Erden, Pınar Esra; Kılıç, Esma

2016-06-01

In this study, two enzyme electrodes based on graphene (GR), Co3O4 nanoparticles and chitosan (CS) or multi-walled carbon nanotubes (MWCNTs), Co3O4 nanoparticles, and CS, were fabricated as novel biosensing platforms for galactose determination, and their performances were compared. Galactose oxidase (GaOx) was immobilized onto the electrode surfaces by crosslinking with glutaraldehyde. Optimum working conditions of the biosensors were investigated and the analytical performance of the biosensors was compared with respect to detection limit, linearity, repeatability, and stability. The MWCNTs-based galactose biosensor provided about 1.6-fold higher sensitivity than its graphene counterpart. Moreover, the linear working range and detection limit of the MWCNTs-based galactose biosensor was superior to the graphene-modified biosensor. The successful application of the purposed biosensors for galactose biosensing in human serum samples was also investigated.

[Application of DNA extraction kit, 'GM quicker' for detection of genetically modified soybeans].

PubMed

Sato, Noriko; Sugiura, Yoshitsugu; Tanaka, Toshitsugu

2012-01-01

Several DNA extraction methods have been officially introduced to detect genetically modified soybeans, but the choice of DNA extraction kits depend on the nature of the samples, such as grains or processed foods. To overcome this disadvantage, we examined whether the GM quicker kit is available for both grains and processed foods. We compared GM quicker with four approved DNA extraction kits in respect of DNA purity, copy numbers of lectin gene, and working time. We found that the DNA quality of GM quicker was superior to that of the other kits for grains, and the procedure was faster. However, in the case of processed foods, GM quicker was not superior to the other kits. We therefore investigated an unapproved GM quicker 3 kit, which is available for DNA extraction from processed foods, such as tofu and boiled soybeans. The GM quicker 3 kit provided good DNA quality from both grains and processed foods, so we made a minor modification of the GM quicker-based protocol that was suitable for processed foods, using GM quicker and its reagents. The modified method enhanced the performance of GM quicker with processed foods. We believe that GM quicker with the modified protocol is an excellent tool to obtain high-quality DNA from grains and processed foods for detection of genetically modified soybeans.

A Facile synthesis of superparamagnetic Fe3O4 nanofibers with superior peroxidase-like catalytic activity for sensitive colorimetric detection of L-cysteine

NASA Astrophysics Data System (ADS)

Chen, Sihui; Chi, Maoqiang; Zhu, Yun; Gao, Mu; Wang, Ce; Lu, Xiaofeng

2018-05-01

Superaramagnetic Fe3O4 nanomaterials are good candidates as enzyme mimics due to their excellent catalytic activity, high stability and facile synthesis. However, the morphology of Fe3O4 nanomaterials has much influence on their enzyme-like catalytic activity. In this work, we have developed a simple polymer-assisted thermochemical reduction approach to prepare Fe3O4 nanofibers for peroxidase-like catalytic applications. The as-prepared Fe3O4 nanofibers show a higher catalytic activity than commercial Fe3O4 nanoparticles. The steady-state kinetic assay result shows that the Michaelis-Menten constant value of the as-obtained Fe3O4 nanofibers is similar to that of horseradish peroxidase (HRP), indicating their superior affinity to the 3,3‧,5,5‧-tetramethylbenzidine (TMB) and H2O2 substrate. Based on the outstanding catalytic activity, a sensing platform for the detection of L-cysteine has been performed and the limit of detection is as low as 0.028 μM. In addition, an excellent selectivity toward L-cysteine over other types of amino acids, glucose and metal ions has been achieved as well. This work offers an original means for the fabrication of superparamagnetic Fe3O4 nanofibers and demonstrates their delightful potential applications in the fields of biosensing, environmental monitoring, and medical diagnostics.

Investigation of statistical iterative reconstruction for dedicated breast CT

PubMed Central

Makeev, Andrey; Glick, Stephen J.

2013-01-01

Purpose: Dedicated breast CT has great potential for improving the detection and diagnosis of breast cancer. Statistical iterative reconstruction (SIR) in dedicated breast CT is a promising alternative to traditional filtered backprojection (FBP). One of the difficulties in using SIR is the presence of free parameters in the algorithm that control the appearance of the resulting image. These parameters require tuning in order to achieve high quality reconstructions. In this study, the authors investigated the penalized maximum likelihood (PML) method with two commonly used types of roughness penalty functions: hyperbolic potential and anisotropic total variation (TV) norm. Reconstructed images were compared with images obtained using standard FBP. Optimal parameters for PML with the hyperbolic prior are reported for the task of detecting microcalcifications embedded in breast tissue. Methods: Computer simulations were used to acquire projections in a half-cone beam geometry. The modeled setup describes a realistic breast CT benchtop system, with an x-ray spectra produced by a point source and an a-Si, CsI:Tl flat-panel detector. A voxelized anthropomorphic breast phantom with 280 μm microcalcification spheres embedded in it was used to model attenuation properties of the uncompressed woman's breast in a pendant position. The reconstruction of 3D images was performed using the separable paraboloidal surrogates algorithm with ordered subsets. Task performance was assessed with the ideal observer detectability index to determine optimal PML parameters. Results: The authors' findings suggest that there is a preferred range of values of the roughness penalty weight and the edge preservation threshold in the penalized objective function with the hyperbolic potential, which resulted in low noise images with high contrast microcalcifications preserved. In terms of numerical observer detectability index, the PML method with optimal parameters yielded substantially improved performance (by a factor of greater than 10) compared to FBP. The hyperbolic prior was also observed to be superior to the TV norm. A few of the best-performing parameter pairs for the PML method also demonstrated superior performance for various radiation doses. In fact, using PML with certain parameter values results in better images, acquired using 2 mGy dose, than FBP-reconstructed images acquired using 6 mGy dose. Conclusions: A range of optimal free parameters for the PML algorithm with hyperbolic and TV norm-based potentials is presented for the microcalcification detection task, in dedicated breast CT. The reported values can be used as starting values of the free parameters, when SIR techniques are used for image reconstruction. Significant improvement in image quality can be achieved by using PML with optimal combination of parameters, as compared to FBP. Importantly, these results suggest improved detection of microcalcifications can be obtained by using PML with lower radiation dose to the patient, than using FBP with higher dose. PMID:23927318

Diagnosis of BK viral nephropathy in the renal allograft biopsy: role of fluorescence in situ hybridization.

PubMed

Wang, Zhen; Portier, Bryce P; Hu, Bo; Chiesa-Vottero, Andres; Myles, Jonathan; Procop, Gary W; Tubbs, Raymond R

2012-09-01

Early recognition of BK viral nephropathy is essential for successful management. Our aim in this study was to evaluate a novel fluorescence in situ hybridization (FISH) assay for detection of BK virus in renal transplant biopsies in the context of standard detection methods. Renal allograft biopsies (n = 108) were analyzed via H&E, immunohistochemistry (IHC) for simian virus 40, and FISH for BK virus. BK virus was detected in 16 (14.8%) cases by H&E, 13 (12%) cases by IHC, 18 (16.6%) cases by FISH, and 19 (17.6%) cases by real-time PCR; 24 of 108 showed a discrepancy in ≥1 testing modalities. Comparison of H&E, IHC, and FISH showed no statistical difference in detection of BK virus. However, performing comparisons between the different tissue-based assays in the context of plasma or urine real-time PCR results showed significant improvement in detection of BK by FISH over H&E (P = 0.02) but not IHC (P = 0.07). This novel FISH-based approach for BK virus identification in renal allograft biopsy tissue mirrored real-time PCR results and showed superior performance to detection of inclusions by H&E. Therefore, use of FISH for BK virus detection in the setting of renal allograft biopsy is a useful and sensitive detection method and could be adopted in any laboratory that currently performs FISH analysis. Copyright © 2012 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Comparison of Fully Automated Computer Analysis and Visual Scoring for Detection of Coronary Artery Disease from Myocardial Perfusion SPECT in a Large Population

PubMed Central

Arsanjani, Reza; Xu, Yuan; Hayes, Sean W.; Fish, Mathews; Lemley, Mark; Gerlach, James; Dorbala, Sharmila; Berman, Daniel S.; Germano, Guido; Slomka, Piotr

2012-01-01

We compared the performance of a fully automated quantification of attenuation-corrected (AC) and non-corrected (NC) myocardial perfusion single photon emission computed tomography (MPS) with the corresponding performance of experienced readers for the detection coronary artery disease (CAD). Methods 995 rest/stress 99mTc-sestamibi MPS studies, [650 consecutive cases with coronary angiography and 345 with likelihood of CAD < 5% (LLk)] were obtained by MPS with AC. Total perfusion deficit (TPD) for AC and NC data were compared to the visual summed stress and rest scores of 2 experienced readers. Visual reads were performed in 4 consecutive steps with the following information progressively revealed: NC data, AC+NC data, computer results, all clinical information. Results The diagnostic accuracy of TPD for detection of CAD was similar to both readers (NC: 82% vs. 84%, AC: 86% vs. 85–87% p = NS) with the exception of second reader when using clinical information (89%, p < 0.05). The Receiver-Operator-Characteristics Areas-Under-Curve (ROC-AUC) for TPD were significantly better than visual reads for NC (0.91 vs. 0.87 and 0.89, p < 0.01) and AC (0.92 vs. 0.90, p < 0.01), and it was comparable to visual reads incorporating all clinical information. Per-vessel accuracy of TPD was superior to one reader for NC (81% vs. 77%, p < 0.05) and AC (83% vs. 78%, p < 0.05) and equivalent to second reader [NC (79%) and AC (81%)]. Per-vessel ROC-AUC for NC (0.83) and AC (0.84) for TPD were better than (0.78–0.80 p < 0.01), and comparable to second reader (0.82–0.84, p = NS), for all steps. Conclusion For the detection of ≥ 70% stenosis based on angiographic criteria, a fully automated computer analysis of NC and AC MPS data is equivalent for per-patient and can be superior for per-vessel analysis, when compared to expert analysis. PMID:23315665

Interactions of cognitive and auditory abilities in congenitally blind individuals.

PubMed

Rokem, Ariel; Ahissar, Merav

2009-02-01

Congenitally blind individuals have been found to show superior performance in perceptual and memory tasks. In the present study, we asked whether superior stimulus encoding could account for performance in memory tasks. We characterized the performance of a group of congenitally blind individuals on a series of auditory, memory and executive cognitive tasks and compared their performance to that of sighted controls matched for age, education and musical training. As expected, we found superior verbal spans among congenitally blind individuals. Moreover, we found superior speech perception, measured by resilience to noise, and superior auditory frequency discrimination. However, when memory span was measured under conditions of equivalent speech perception, by adjusting the signal to noise ratio for each individual to the same level of perceptual difficulty (80% correct), the advantage in memory span was completely eliminated. Moreover, blind individuals did not possess any advantage in cognitive executive functions, such as manipulation of items in memory and math abilities. We propose that the short-term memory advantage of blind individuals results from better stimulus encoding, rather than from superiority at subsequent processing stages.

Multicenter comparison of 18F-FDG and 68Ga-DOTA-peptide PET/CT for pulmonary carcinoid.

PubMed

Lococo, Filippo; Perotti, Germano; Cardillo, Giuseppe; De Waure, Chiara; Filice, Angelina; Graziano, Paolo; Rossi, Giulio; Sgarbi, Giorgio; Stefanelli, Antonella; Giordano, Alessandro; Granone, Pierluigi; Rindi, Guido; Versari, Annibale; Rufini, Vittoria

2015-03-01

The aims of this study were to retrospectively evaluate and compare the detection rate (DR) of 68Ga-DOTA-peptide and 18F-FDG PET/CT in the preoperative workup of patients with pulmonary carcinoid (PC) and to assess the utility of various functional indices obtained with the 2 tracers in predicting the histological characterization of PC, that is, typical versus atypical. Thirty-three consecutive patients with confirmed PC referred for 18F-FDG and 68Ga-DOTA-peptide PET/CT in 2 centers between January 2009 and April 2013 were included. The semiquantitative evaluation included the SUV max, the SUV of the tumor relative to the maximal liver uptake for 18F-FDG (SUV T/L) or the maximal spleen uptake for 68Ga-DOTA-peptides (SUV T/S), the ratio between SUV max of 68Ga-DOTA-peptides PET/CT, and the SUV max of 18F-FDG PET/CT (SUV max ratio). Histology was used as reference standard. Definitive diagnosis consisted of 23 typical carcinoids (TCs) and 10 atypical carcinoids. 18F-FDG PET/CT was positive in 18 cases and negative in 15 (55% DR). 68Ga-DOTA-peptide PET/CT was positive in 26 cases and negative in 7 (79% DR). In the subgroup analysis, 68Ga-DOTA-peptide PET/CT was superior in detecting TC (91% DR; P < 0.001), whereas 18F-FDG PET/CT was superior in detecting atypical carcinoid (100% DR; P = 0.04). The SUV max ratio was the most accurate semiquantitative index in identifying TC. Overall diagnostic performance of PET/CT in detecting PC is optimal when integrating 18F-FDG and 68Ga-DOTA-peptide PET/CT findings. In the subgroup analysis, the SUV max ratio seems to be the most accurate index in predicting TC. Both methods should be performed when PC is suspected or when the histological subtype is undefined.

A Multiagent-based Intrusion Detection System with the Support of Multi-Class Supervised Classification

NASA Astrophysics Data System (ADS)

Shyu, Mei-Ling; Sainani, Varsha

The increasing number of network security related incidents have made it necessary for the organizations to actively protect their sensitive data with network intrusion detection systems (IDSs). IDSs are expected to analyze a large volume of data while not placing a significantly added load on the monitoring systems and networks. This requires good data mining strategies which take less time and give accurate results. In this study, a novel data mining assisted multiagent-based intrusion detection system (DMAS-IDS) is proposed, particularly with the support of multiclass supervised classification. These agents can detect and take predefined actions against malicious activities, and data mining techniques can help detect them. Our proposed DMAS-IDS shows superior performance compared to central sniffing IDS techniques, and saves network resources compared to other distributed IDS with mobile agents that activate too many sniffers causing bottlenecks in the network. This is one of the major motivations to use a distributed model based on multiagent platform along with a supervised classification technique.

Community detection enhancement using non-negative matrix factorization with graph regularization

NASA Astrophysics Data System (ADS)

Liu, Xiao; Wei, Yi-Ming; Wang, Jian; Wang, Wen-Jun; He, Dong-Xiao; Song, Zhan-Jie

2016-06-01

Community detection is a meaningful task in the analysis of complex networks, which has received great concern in various domains. A plethora of exhaustive studies has made great effort and proposed many methods on community detection. Particularly, a kind of attractive one is the two-step method which first makes a preprocessing for the network and then identifies its communities. However, not all types of methods can achieve satisfactory results by using such preprocessing strategy, such as the non-negative matrix factorization (NMF) methods. In this paper, rather than using the above two-step method as most works did, we propose a graph regularized-based model to improve, specialized, the NMF-based methods for the detection of communities, namely NMFGR. In NMFGR, we introduce the similarity metric which contains both the global and local information of networks, to reflect the relationships between two nodes, so as to improve the accuracy of community detection. Experimental results on both artificial and real-world networks demonstrate the superior performance of NMFGR to some competing methods.

Early detection of invasive fishes in Lake Superior

EPA Science Inventory

Invasive species pose a serious threat to the Great Lakes warranting continual monitoring for the arrival of new species. Three locations in Lake Superior were identified as "high risk" for new introductions: St. Louis River near Duluth, MN, Upper St. Marys River near S...

Early detection of non-indigenous fishes in Lake Superior

EPA Science Inventory

Invasive species pose a serious threat to the ecological stability of the Great Lakes warranting continual monitoring for the arrival of new species. Three locations in Lake Superior were identified as “high risk” for new introductions: St. Louis River near Duluth, M...

Deep Convolutional Neural Network-Based Early Automated Detection of Diabetic Retinopathy Using Fundus Image.

PubMed

Xu, Kele; Feng, Dawei; Mi, Haibo

2017-11-23

The automatic detection of diabetic retinopathy is of vital importance, as it is the main cause of irreversible vision loss in the working-age population in the developed world. The early detection of diabetic retinopathy occurrence can be very helpful for clinical treatment; although several different feature extraction approaches have been proposed, the classification task for retinal images is still tedious even for those trained clinicians. Recently, deep convolutional neural networks have manifested superior performance in image classification compared to previous handcrafted feature-based image classification methods. Thus, in this paper, we explored the use of deep convolutional neural network methodology for the automatic classification of diabetic retinopathy using color fundus image, and obtained an accuracy of 94.5% on our dataset, outperforming the results obtained by using classical approaches.

On-site comprehensive analysis of explosives using HPLC-UV-PAED

NASA Astrophysics Data System (ADS)

Marple, Ronita L.; LaCourse, William R.

2004-03-01

High-performance liquid chromatography with ultra violet and photo-assisted electrochemical detection (HPLC-UV-PAED) has been developed for the sensitive and selective detection of explosives in ground water and soil extracts. Fractionation and preconcentration of explosives is accomplished with on-line solid phase extraction (SPE), which minimizes sample pretreatment and enables faster and more accurate on-site assessment of a contaminated site. Detection limits are equivalent or superior (i.e., <1 part-per-trillion for HMX) to those achieved using the Environmental Protection Agency (EPA) Method 8330. This approach is more broadly applicable, as it is capable of determining a wider range of organic nitro compounds. Soil samples are extracted using pressurized fluid extraction (PFE), and this technique is automatable, field-compatible, and environmentally friendly, adding to the overall efficiency of the methodology.

The Morphologies of the Semiconductor Oxides and Their Gas-Sensing Properties

PubMed Central

Lv, Xin; Li, Shuang; Wang, Qingji

2017-01-01

Semiconductor oxide chemoresistive gas sensors are widely used for detecting deleterious gases due to low cost, simple preparation, rapid response and high sensitivity. The performance of gas sensor is greatly affected by the morphology of the semiconductor oxide. There are many semiconductor oxide morphologies, including zero-dimensional, one-dimensional, two-dimensional and three-dimensional ones. The semiconductor oxides with different morphologies significantly enhance the gas-sensing performance. Among the various morphologies, hollow nanostructures and core-shell nanostructures are always the focus of research in the field of gas sensors due to their distinctive structural characteristics and superior performance. Herein the morphologies of semiconductor oxides and their gas-sensing properties are reviewed. This review also proposes a potential strategy for the enhancement of gas-sensing performance in the future. PMID:29189714

Border preserving skin lesion segmentation

NASA Astrophysics Data System (ADS)

Kamali, Mostafa; Samei, Golnoosh

2008-03-01

Melanoma is a fatal cancer with a growing incident rate. However it could be cured if diagnosed in early stages. The first step in detecting melanoma is the separation of skin lesion from healthy skin. There are particular features associated with a malignant lesion whose successful detection relies upon accurately extracted borders. We propose a two step approach. First, we apply K-means clustering method (to 3D RGB space) that extracts relatively accurate borders. In the second step we perform an extra refining step for detecting the fading area around some lesions as accurately as possible. Our method has a number of novelties. Firstly as the clustering method is directly applied to the 3D color space, we do not overlook the dependencies between different color channels. In addition, it is capable of extracting fine lesion borders up to pixel level in spite of the difficulties associated with fading areas around the lesion. Performing clustering in different color spaces reveals that 3D RGB color space is preferred. The application of the proposed algorithm to an extensive data-base of skin lesions shows that its performance is superior to that of existing methods both in terms of accuracy and computational complexity.

New GasB-based single-mode diode lasers in the NIR and MIR spectral regime for sensor applications

NASA Astrophysics Data System (ADS)

Milde, Tobias; Hoppe, Morten; Tatenguem, Herve; Honsberg, Martin; Mordmüller, Mario; O'Gorman, James; Schade, Wolfgang; Sacher, Joachim

2018-02-01

The NIR/MIR region between 1.8μm and 3.5μm contains important absorption lines for gas detection. State of the art are InP laser based setups, which show poor gain above 1.8μm and cannot be applied beyond 2.1μm. GaSb laser show a significantly higher output power (100mW for Fabry-Perot, 30mW for DFB). The laser design is presented with simulation and actual performance data. The superior performance of the GaSb lasers is verified in gas sensing applications. TDLAS and QEPAS measurements at trace gases like CH4, CO2 and N2O are shown to prove the spectroscopy performance.

Performance of the new automated Abbott RealTime MTB assay for rapid detection of Mycobacterium tuberculosis complex in respiratory specimens.

PubMed

Chen, J H K; She, K K K; Kwong, T-C; Wong, O-Y; Siu, G K H; Leung, C-C; Chang, K-C; Tam, C-M; Ho, P-L; Cheng, V C C; Yuen, K-Y; Yam, W-C

2015-09-01

The automated high-throughput Abbott RealTime MTB real-time PCR assay has been recently launched for Mycobacterium tuberculosis complex (MTBC) clinical diagnosis. This study would like to evaluate its performance. We first compared its diagnostic performance with the Roche Cobas TaqMan MTB assay on 214 clinical respiratory specimens. Prospective analysis of a total 520 specimens was then performed to further evaluate the Abbott assay. The Abbott assay showed a lower limit of detection at 22.5 AFB/ml, which was more sensitive than the Cobas assay (167.5 AFB/ml). The two assays demonstrated a significant difference in diagnostic performance (McNemar's test; P = 0.0034), in which the Abbott assay presented significantly higher area under curve (AUC) than the Cobas assay (1.000 vs 0.880; P = 0.0002). The Abbott assay demonstrated extremely low PCR inhibition on clinical respiratory specimens. The automated Abbott assay required only very short manual handling time (0.5 h), which could help to improve the laboratory management. In the prospective analysis, the overall estimates for sensitivity and specificity of the Abbott assay were both 100 % among smear-positive specimens, whereas the smear-negative specimens were 96.7 and 96.1 %, respectively. No cross-reactivity with non-tuberculosis mycobacterial species was observed. The superiority in sensitivity of the Abbott assay for detecting MTBC in smear-negative specimens could further minimize the risk in MTBC false-negative detection. The new Abbott RealTime MTB assay has good diagnostic performance which can be a useful diagnostic tool for rapid MTBC detection in clinical laboratories.

Sex, Age, and Cognitive Correlates of Asymmetries in Thickness of the Cortical Mantle Across the Life Span

PubMed Central

Plessen, Kerstin J.; Hugdahl, Kenneth; Bansal, Ravi; Hao, Xuejun

2014-01-01

We assessed the correlations of age, sex, and cognitive performance with measures of asymmetry in cortical thickness on high-resolution MRIs in 215 healthy human children and adults, 7–59 years of age. A left > right asymmetry in thickness of the cortical mantle was present throughout the entire lateral, dorsal, and mesial surfaces of the frontal lobe, extending into primary sensory, superior parietal, and anterior superior temporal cortices. A right > left asymmetry was present in the lateral, mesial, and dorsal surfaces of the posterior temporal, parietal, and occipital cortices, as well as in the entire inferior surface of the brain. An exaggerated left > right asymmetry was detected in females in anterior brain regions, and an exaggerated right > left asymmetry was detected in males in the orbitofrontal, inferior parietal, and inferior occipital cortices. Weaker moderating effects of sex were scattered along the mesial surface of the brain. Age significantly moderated asymmetry measures in the inferior sensorimotor, inferior parietal, posterior temporal, and inferior occipital cortices. The age × asymmetry interaction derived from a steeper decline in cortical thickness with age in the right hemisphere than in the left on the lateral surface, whereas it derived from a steeper decline with age in the left hemisphere than in the right on the mesial surface. Finally, measures of performance on working memory and vocabulary tasks improved with increasing magnitudes of normal asymmetries in regions thought to support these cognitive capacities. PMID:24790200

[Investigation of fat in the dural sinus].

PubMed

Tokiguchi, S

1991-08-25

Detection of fat in the cranium usually indicates the presence of a fat-containing tumor such as lipoma, dermoid cyst or teratoma. However, since 1982, Hasso et al demonstrated with CT the presence of normal adipose tissue in the cavernous sinus, the mere existence of fat in the cranium does not necessarily mean the presence of a fatty tumor. The author first described fat deposition in the superior sagittal sinus and torcular Herophili following a CT study performed in 1986. The purpose of this study was to investigate the distribution, frequency, and anatomical correlations of fat in the dural sinus as demonstrated on CT. Fat was detected in the cavernous sinus in 20% of all cases (492/2408), and occurred more frequently (25%) in those older than 50 years. Fat was less frequent in the other dural sinuses (3%; 75/2296). The most common location was the torcular Herophili, followed in decreasing order of frequency by the straight sinus, inferior sagittal sinus, superior sagittal sinus and transverse sinus. Pathological examination was performed in three cases. Fat deposition was composed of normal adipose tissue and was devoid of fibrous encapsulation or infiltration. In one case, the fat seemed to be partly exposed to the subarachnoid space on CT, whereas on autopsy, thin dura mater covering the fat nodule was confirmed. Fat in the dural sinus must be differentiated from cavernous nodule or sinus thrombosis. The Hounsfield unit may be helpful in making a definitive diagnosis.

Sex, age, and cognitive correlates of asymmetries in thickness of the cortical mantle across the life span.

PubMed

Plessen, Kerstin J; Hugdahl, Kenneth; Bansal, Ravi; Hao, Xuejun; Peterson, Bradley S

2014-04-30

We assessed the correlations of age, sex, and cognitive performance with measures of asymmetry in cortical thickness on high-resolution MRIs in 215 healthy human children and adults, 7-59 years of age. A left > right asymmetry in thickness of the cortical mantle was present throughout the entire lateral, dorsal, and mesial surfaces of the frontal lobe, extending into primary sensory, superior parietal, and anterior superior temporal cortices. A right > left asymmetry was present in the lateral, mesial, and dorsal surfaces of the posterior temporal, parietal, and occipital cortices, as well as in the entire inferior surface of the brain. An exaggerated left > right asymmetry was detected in females in anterior brain regions, and an exaggerated right > left asymmetry was detected in males in the orbitofrontal, inferior parietal, and inferior occipital cortices. Weaker moderating effects of sex were scattered along the mesial surface of the brain. Age significantly moderated asymmetry measures in the inferior sensorimotor, inferior parietal, posterior temporal, and inferior occipital cortices. The age × asymmetry interaction derived from a steeper decline in cortical thickness with age in the right hemisphere than in the left on the lateral surface, whereas it derived from a steeper decline with age in the left hemisphere than in the right on the mesial surface. Finally, measures of performance on working memory and vocabulary tasks improved with increasing magnitudes of normal asymmetries in regions thought to support these cognitive capacities.

Category-Specific Comparison of Univariate Alerting Methods for Biosurveillance Decision Support

PubMed Central

Elbert, Yevgeniy; Hung, Vivian; Burkom, Howard

2013-01-01

Objective For a multi-source decision support application, we sought to match univariate alerting algorithms to surveillance data types to optimize detection performance. Introduction Temporal alerting algorithms commonly used in syndromic surveillance systems are often adjusted for data features such as cyclic behavior but are subject to overfitting or misspecification errors when applied indiscriminately. In a project for the Armed Forces Health Surveillance Center to enable multivariate decision support, we obtained 4.5 years of out-patient, prescription and laboratory test records from all US military treatment facilities. A proof-of-concept project phase produced 16 events with multiple evidence corroboration for comparison of alerting algorithms for detection performance. We used the representative streams from each data source to compare sensitivity of 6 algorithms to injected spikes, and we used all data streams from 16 known events to compare them for detection timeliness. Methods The six methods compared were: Holt-Winters generalized exponential smoothing method (1)automated choice between daily methods, regression and an exponential weighted moving average (2)adaptive daily Shewhart-type chartadaptive one-sided daily CUSUMEWMA applied to 7-day means with a trend correction; and7-day temporal scan statistic Sensitivity testing: We conducted comparative sensitivity testing for categories of time series with similar scales and seasonal behavior. We added multiples of the standard deviation of each time series as single-day injects in separate algorithm runs. For each candidate method, we then used as a sensitivity measure the proportion of these runs for which the output of each algorithm was below alerting thresholds estimated empirically for each algorithm using simulated data streams. We identified the algorithm(s) whose sensitivity was most consistently high for each data category. For each syndromic query applied to each data source (outpatient, lab test orders, and prescriptions), 502 authentic time series were derived, one for each reporting treatment facility. Data categories were selected in order to group time series with similar expected algorithm performance: Median > 100 < Median ≤ 10Median = 0Lag 7 Autocorrelation Coefficient ≥ 0.2Lag 7 Autocorrelation Coefficient < 0.2 Timeliness testing: For the timeliness testing, we avoided artificiality of simulated signals by measuring alerting detection delays in the 16 corroborated outbreaks. The multiple time series from these events gave a total of 141 time series with outbreak intervals for timeliness testing. The following measures were computed to quantify timeliness of detection: Median Detection Delay – median number of days to detect the outbreak.Penalized Mean Detection Delay –mean number of days to detect the outbreak with outbreak misses penalized as 1 day plus the maximum detection time. Results Based on the injection results, the Holt-Winters algorithm was most sensitive among time series with positive medians. The adaptive CUSUM and the Shewhart methods were most sensitive for data streams with median zero. Table 1 provides timeliness results using the 141 outbreak-associated streams on sparse (Median=0) and non-sparse data categories. [Insert table #1 here] Data median Detection Delay, days Holt-winters Regression EWMA Adaptive Shewhart Adaptive CUSUM 7-day Trend-adj. EWMA 7-day Temporal Scan Median 0 Median 3 2 4 2 4.5 2 Penalized Mean 7.2 7 6.6 6.2 7.3 7.6 Median >0 Median 2 2 2.5 2 6 4 Penalized Mean 6.1 7 7.2 7.1 7.7 6.6 The gray shading in the table 1 indicates methods with shortest detection delays for sparse and non-sparse data streams. The Holt-Winters method was again superior for non-sparse data. For data with median=0, the adaptive CUSUM was superior for a daily false alarm probability of 0.01, but the Shewhart method was timelier for more liberal thresholds. Conclusions Both kinds of detection performance analysis showed the method based on Holt-Winters exponential smoothing superior on non-sparse time series with day-of-week effects. The adaptive CUSUM and She-whart methods proved optimal on sparse data and data without weekly patterns.

Eye-tracking AFROC study of the influence of experience and training on chest x-ray interpretation

NASA Astrophysics Data System (ADS)

Manning, David; Ethell, Susan C.; Crawford, Trevor

2003-05-01

Four observer groups with different levels of expertise were tested in an investigation into the comparative nature of expert performance. The radiological task was the detection and localization of significant pulmonary nodules in postero-anterior vies of the chest in adults. Three test banks of 40 images were used. The observer groups were 6 experienced radiographers prior to a six month training program in chest image interpretation, the same radiographers after their tr4aining program, and 6 fresher undergraduate radiography students. Eye tracking was carried out on all observers to demonstrate differences in visual activity and nodule detection performance was measured with an AFROC technique. Detection performances of the four groups showed the radiologists and radiographers after training were measurably superior at the task. The eye-tracking parameters saccadic length, number of fixations visual coverage and scrutiny timer per film were measured for all subjects and compared. The missed nodules fixated and not fixated were also determined for the radiologist group. Results have shown distinct stylistic differences in the visual scanning strategies between the experienced and inexperienced observers that we believe can be generalized into a description of characteristics of expert versus non-expert performance. The findings will be used in the educational program of image interpretation for non-radiology practitioners.

Optimal control theory for non-scalar-valued performance criteria. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Gerring, H. P.

1971-01-01

The theory of optimal control for nonscalar-valued performance criteria is discussed. In the space, where the performance criterion attains its value, the relations better than, worse than, not better than, and not worse than are defined by a partial order relation. The notion of optimality splits up into superiority and non-inferiority, because worse than is not the complement of better than, in general. A superior solution is better than every other solution. A noninferior solution is not worse than any other solution. Noninferior solutions have been investigated particularly for vector-valued performance criteria. Superior solutions for non-scalar-valued performance criteria attaining their values in abstract partially ordered spaces are emphasized. The main result is the infimum principle which constitutes necessary conditions for a control to be a superior solution to an optimal control problem.

Altered resting-state functional connectivity in post-traumatic stress disorder: a perfusion MRI study

NASA Astrophysics Data System (ADS)

Li, Baojuan; Liu, Jian; Liu, Yang; Lu, Hong-Bing; Yin, Hong

2013-03-01

The majority of studies on posttraumatic stress disorder (PTSD) so far have focused on delineating patterns of activations during cognitive processes. Recently, more and more researches have started to investigate functional connectivity in PTSD subjects using BOLD-fMRI. Functional connectivity analysis has been demonstrated as a powerful approach to identify biomarkers of different brain diseases. This study aimed to detect resting-state functional connectivity abnormities in patients with PTSD using arterial spin labeling (ASL) fMRI. As a completely non-invasive technique, ASL allows quantitative estimates of cerebral blood flow (CBF). Compared with BOLD-fMRI, ASL fMRI has many advantages, including less low-frequency signal drifts, superior functional localization, etc. In the current study, ASL images were collected from 10 survivors in mining disaster with recent onset PTSD and 10 survivors without PTSD. Decreased regional CBF in the right middle temporal gyrus, lingual gyrus, and postcentral gyrus was detected in the PTSD patients. Seed-based resting-state functional connectivity analysis was performed using an area in the right middle temporal gyrus as region of interest. Compared with the non-PTSD group, the PTSD subjects demonstrated increased functional connectivity between the right middle temporal gyrus and the right superior temporal gyrus, the left middle temporal gyrus. Meanwhile, decreased functional connectivity between the right middle temporal gyrus and the right postcentral gyrus, the right superior parietal lobule was also found in the PTSD patients. This is the first study which investigated resting-state functional connectivity in PTSD using ASL images. The results may provide new insight into the neural substrates of PTSD.

Multiple fault separation and detection by joint subspace learning for the health assessment of wind turbine gearboxes

NASA Astrophysics Data System (ADS)

Du, Zhaohui; Chen, Xuefeng; Zhang, Han; Zi, Yanyang; Yan, Ruqiang

2017-09-01

The gearbox of a wind turbine (WT) has dominant failure rates and highest downtime loss among all WT subsystems. Thus, gearbox health assessment for maintenance cost reduction is of paramount importance. The concurrence of multiple faults in gearbox components is a common phenomenon due to fault induction mechanism. This problem should be considered before planning to replace the components of the WT gearbox. Therefore, the key fault patterns should be reliably identified from noisy observation data for the development of an effective maintenance strategy. However, most of the existing studies focusing on multiple fault diagnosis always suffer from inappropriate division of fault information in order to satisfy various rigorous decomposition principles or statistical assumptions, such as the smooth envelope principle of ensemble empirical mode decomposition and the mutual independence assumption of independent component analysis. Thus, this paper presents a joint subspace learning-based multiple fault detection (JSL-MFD) technique to construct different subspaces adaptively for different fault patterns. Its main advantage is its capability to learn multiple fault subspaces directly from the observation signal itself. It can also sparsely concentrate the feature information into a few dominant subspace coefficients. Furthermore, it can eliminate noise by simply performing coefficient shrinkage operations. Consequently, multiple fault patterns are reliably identified by utilizing the maximum fault information criterion. The superiority of JSL-MFD in multiple fault separation and detection is comprehensively investigated and verified by the analysis of a data set of a 750 kW WT gearbox. Results show that JSL-MFD is superior to a state-of-the-art technique in detecting hidden fault patterns and enhancing detection accuracy.

Sensitivity Comparison of Vapor Trace Detection of Explosives Based on Chemo-Mechanical Sensing with Optical Detection and Capacitive Sensing with Electronic Detection

PubMed Central

Strle, Drago; Štefane, Bogdan; Zupanič, Erik; Trifkovič, Mario; Maček, Marijan; Jakša, Gregor; Kvasič, Ivan; Muševič, Igor

2014-01-01

The article offers a comparison of the sensitivities for vapour trace detection of Trinitrotoluene (TNT) explosives of two different sensor systems: a chemo-mechanical sensor based on chemically modified Atomic Force Microscope (AFM) cantilevers based on Micro Electro Mechanical System (MEMS) technology with optical detection (CMO), and a miniature system based on capacitive detection of chemically functionalized planar capacitors with interdigitated electrodes with a comb-like structure with electronic detection (CE). In both cases (either CMO or CE), the sensor surfaces are chemically functionalized with a layer of APhS (trimethoxyphenylsilane) molecules, which give the strongest sensor response for TNT. The construction and calibration of a vapour generator is also presented. The measurements of the sensor response to TNT are performed under equal conditions for both systems, and the results show that CE system with ultrasensitive electronics is far superior to optical detection using MEMS. Using CMO system, we can detect 300 molecules of TNT in 10+12 molecules of N2 carrier gas, whereas the CE system can detect three molecules of TNT in 10+12 molecules of carrier N2. PMID:24977388

Detecting autologous blood transfusions: a comparison of three passport approaches and four blood markers.

PubMed

Mørkeberg, J; Sharpe, K; Belhage, B; Damsgaard, R; Schmidt, W; Prommer, N; Gore, C J; Ashenden, M J

2011-04-01

Blood passport has been suggested as an indirect tool to detect various kinds of blood manipulations. Autologous blood transfusions are currently undetectable, and the objective of this study was to examine the sensitivities of different blood markers and blood passport approaches in order to determine the best approach to detect autologous blood transfusions. Twenty-nine subjects were transfused with either one (n=8) or three (n=21) bags of autologous blood. Hemoglobin concentration ([Hb]), percentage of reticulocytes (%ret) and hemoglobin mass (Hbmass) were measured 1 day before reinfusion and six times after reinfusion. The sensitivity and specificity of a novel marker, Hbmr (based on Hbmass and %ret), was evaluated together with [Hb], Hbmass and OFF-hr by different passport methods. Our novel Hbmr marker showed superior sensitivity in detecting the highest dosage of transfused blood, with OFF-hr showing equal or superior sensitivities at lower dosages. Hbmr and OFF-hr showed superior but equal sensitivities from 1 to 4 weeks after transfusion compared with [Hb] and Hbmass, with Hbmass being the only tenable prospect to detect acute transfusions. Because autologous blood transfusions can be an acute practice with blood withdrawal and reinfusion within a few days, Hbmass seems to be the only option for revealing this practice. © 2009 John Wiley & Sons A/S.

Fusion of Scores in a Detection Context Based on Alpha Integration.

PubMed

Soriano, Antonio; Vergara, Luis; Ahmed, Bouziane; Salazar, Addisson

2015-09-01

We present a new method for fusing scores corresponding to different detectors (two-hypotheses case). It is based on alpha integration, which we have adapted to the detection context. Three optimization methods are presented: least mean square error, maximization of the area under the ROC curve, and minimization of the probability of error. Gradient algorithms are proposed for the three methods. Different experiments with simulated and real data are included. Simulated data consider the two-detector case to illustrate the factors influencing alpha integration and demonstrate the improvements obtained by score fusion with respect to individual detector performance. Two real data cases have been considered. In the first, multimodal biometric data have been processed. This case is representative of scenarios in which the probability of detection is to be maximized for a given probability of false alarm. The second case is the automatic analysis of electroencephalogram and electrocardiogram records with the aim of reproducing the medical expert detections of arousal during sleeping. This case is representative of scenarios in which probability of error is to be minimized. The general superior performance of alpha integration verifies the interest of optimizing the fusing parameters.

Laser Engineered Graphene Paper for Mass Spectrometry Imaging

PubMed Central

Qian, Kun; Zhou, Liang; Liu, Jian; Yang, Jie; Xu, Hongyi; Yu, Meihua; Nouwens, Amanda; Zou, Jin; Monteiro, Michael J.; Yu, Chengzhong

2013-01-01

A pulsed laser engineering approach is developed to prepare novel functional graphene paper with graphitic nanospheres homogeneously decorated on the surface and the superior performance of engineered paper is revealed in matrix-free mass spectrometry (MS) detection and imaging. We demonstrate that the stability of graphene paper under intense irradiation can be dramatically increased through a designed laser engineering process by forming densely packed graphitic nanospheres on the paper surface. Moreover, the surface hydrophobicity is enhanced and electric conductivity is improved. The engineered graphene paper can image the invisible micro-patterns of trace amount molecules and increases the detection limit towards diverse molecules by over two orders of magnitude compared to the pristine graphene paper and commercial products in MS analysis. PMID:23475267

Atom-Based Sensing of Weak Radio Frequency Electric Fields Using Homodyne Readout

PubMed Central

Kumar, Santosh; Fan, Haoquan; Kübler, Harald; Sheng, Jiteng; Shaffer, James P.

2017-01-01

We utilize a homodyne detection technique to achieve a new sensitivity limit for atom-based, absolute radio-frequency electric field sensing of 5 μV cm−1 Hz−1/2. A Mach-Zehnder interferometer is used for the homodyne detection. With the increased sensitivity, we investigate the dominant dephasing mechanisms that affect the performance of the sensor. In particular, we present data on power broadening, collisional broadening and transit time broadening. Our results are compared to density matrix calculations. We show that photon shot noise in the signal readout is currently a limiting factor. We suggest that new approaches with superior readout with respect to photon shot noise are needed to increase the sensitivity further. PMID:28218308

Theory of CW lidar aerosol backscatter measurements and development of a 2.1 microns solid-state pulsed laser radar for aerosol backscatter profiling

NASA Technical Reports Server (NTRS)

Kavaya, Michael J.; Henderson, Sammy W.; Frehlich, R. G.

1991-01-01

The performance and calibration of a focused, continuous wave, coherent detection CO2 lidar operated for the measurement of atmospheric backscatter coefficient, B(m), was examined. This instrument functions by transmitting infrared (10 micron) light into the atmosphere and collecting the light which is scattered in the rearward direction. Two distinct modes of operation were considered. In volume mode, the scattered light energy from many aerosols is detected simultaneously, whereas in the single particle mode (SPM), the scattered light energy from a single aerosol is detected. The analysis considered possible sources of error for each of these two cases, and also considered the conditions where each technique would have superior performance. The analysis showed that, within reasonable assumptions, the value of B(m) could be accurately measured by either the VM or the SPM method. The understanding of the theory developed during the analysis was also applied to a pulsed CO2 lidar. Preliminary results of field testing of a solid state 2 micron lidar using a CW oscillator is included.

PdCo alloy nanoparticle-embedded carbon nanofiber for ultrasensitive nonenzymatic detection of hydrogen peroxide and nitrite.

PubMed

Liu, Dong; Guo, Qiaohui; Zhang, Xueping; Hou, Haoqing; You, Tianyan

2015-07-15

PdCo alloy nanoparticle-embedded carbon nanofiber (PdCo/CNF) prepared by electrospinning and thermal treatment was employed as a high-performance platform for the determination of hydrogen peroxide and nitrite. The as-obtained PdCo/CNF were characterized by transmission electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction. Electrochemical impedance spectroscopy, cyclic voltammetry and differential pulse voltammetry were employed to investigate the electrochemical behaviors of the resultant biosensor. The proposed PdCo/CNF-based biosensor showed excellent analytical performances toward hydrogen peroxide (detection limit: 0.1 μM; linear range: 0.2 μM-23.5 mM) and nitrite (detection limit: 0.2 μM; linear range: 0.4-30 μM and 30-400 μM). The superior analytical properties could be attributed to the synergic effect and firmly embedment of well-dispersed PdCo alloy nanoparticles. These attractive electrochemical properties make this robust electrode material promising for the development of effective electrochemical sensors. Copyright © 2015 Elsevier Inc. All rights reserved.

Detection Copy Number Variants from NGS with Sparse and Smooth Constraints.

PubMed

Zhang, Yue; Cheung, Yiu-Ming; Xu, Bo; Su, Weifeng

2017-01-01

It is known that copy number variations (CNVs) are associated with complex diseases and particular tumor types, thus reliable identification of CNVs is of great potential value. Recent advances in next generation sequencing (NGS) data analysis have helped manifest the richness of CNV information. However, the performances of these methods are not consistent. Reliably finding CNVs in NGS data in an efficient way remains a challenging topic, worthy of further investigation. Accordingly, we tackle the problem by formulating CNVs identification into a quadratic optimization problem involving two constraints. By imposing the constraints of sparsity and smoothness, the reconstructed read depth signal from NGS is anticipated to fit the CNVs patterns more accurately. An efficient numerical solution tailored from alternating direction minimization (ADM) framework is elaborated. We demonstrate the advantages of the proposed method, namely ADM-CNV, by comparing it with six popular CNV detection methods using synthetic, simulated, and empirical sequencing data. It is shown that the proposed approach can successfully reconstruct CNV patterns from raw data, and achieve superior or comparable performance in detection of the CNVs compared to the existing counterparts.

Assessing the performance of a motion tracking system based on optical joint transform correlation

NASA Astrophysics Data System (ADS)

Elbouz, M.; Alfalou, A.; Brosseau, C.; Ben Haj Yahia, N.; Alam, M. S.

2015-08-01

We present an optimized system specially designed for the tracking and recognition of moving subjects in a confined environment (such as an elderly remaining at home). In the first step of our study, we use a VanderLugt correlator (VLC) with an adapted pre-processing treatment of the input plane and a postprocessing of the correlation plane via a nonlinear function allowing us to make a robust decision. The second step is based on an optical joint transform correlation (JTC)-based system (NZ-NL-correlation JTC) for achieving improved detection and tracking of moving persons in a confined space. The proposed system has been found to have significantly superior discrimination and robustness capabilities allowing to detect an unknown target in an input scene and to determine the target's trajectory when this target is in motion. This system offers robust tracking performance of a moving target in several scenarios, such as rotational variation of input faces. Test results obtained using various real life video sequences show that the proposed system is particularly suitable for real-time detection and tracking of moving objects.

Aspects of detection and tracking of ground targets from an airborne EO/IR sensor

NASA Astrophysics Data System (ADS)

Balaji, Bhashyam; Sithiravel, Rajiv; Daya, Zahir; Kirubarajan, Thiagalingam

2015-05-01

An airborne EO/IR (electro-optical/infrared) camera system comprises of a suite of sensors, such as a narrow and wide field of view (FOV) EO and mid-wave IR sensors. EO/IR camera systems are regularly employed on military and search and rescue aircrafts. The EO/IR system can be used to detect and identify objects rapidly in daylight and at night, often with superior performance in challenging conditions such as fog. There exist several algorithms for detecting potential targets in the bearing elevation grid. The nonlinear filtering problem is one of estimation of the kinematic parameters from bearing and elevation measurements from a moving platform. In this paper, we developed a complete model for the state of a target as detected by an airborne EO/IR system and simulated a typical scenario with single target with 1 or 2 airborne sensors. We have demonstrated the ability to track the target with `high precision' and noted the improvement from using two sensors on a single platform or on separate platforms. The performance of the Extended Kalman filter (EKF) is investigated on simulated data. Image/video data collected from an IR sensor on an airborne platform are processed using an image tracking by detection algorithm.

Multi-class geospatial object detection and geographic image classification based on collection of part detectors

NASA Astrophysics Data System (ADS)

Cheng, Gong; Han, Junwei; Zhou, Peicheng; Guo, Lei

2014-12-01

The rapid development of remote sensing technology has facilitated us the acquisition of remote sensing images with higher and higher spatial resolution, but how to automatically understand the image contents is still a big challenge. In this paper, we develop a practical and rotation-invariant framework for multi-class geospatial object detection and geographic image classification based on collection of part detectors (COPD). The COPD is composed of a set of representative and discriminative part detectors, where each part detector is a linear support vector machine (SVM) classifier used for the detection of objects or recurring spatial patterns within a certain range of orientation. Specifically, when performing multi-class geospatial object detection, we learn a set of seed-based part detectors where each part detector corresponds to a particular viewpoint of an object class, so the collection of them provides a solution for rotation-invariant detection of multi-class objects. When performing geographic image classification, we utilize a large number of pre-trained part detectors to discovery distinctive visual parts from images and use them as attributes to represent the images. Comprehensive evaluations on two remote sensing image databases and comparisons with some state-of-the-art approaches demonstrate the effectiveness and superiority of the developed framework.

SvABA: genome-wide detection of structural variants and indels by local assembly.

PubMed

Wala, Jeremiah A; Bandopadhayay, Pratiti; Greenwald, Noah F; O'Rourke, Ryan; Sharpe, Ted; Stewart, Chip; Schumacher, Steve; Li, Yilong; Weischenfeldt, Joachim; Yao, Xiaotong; Nusbaum, Chad; Campbell, Peter; Getz, Gad; Meyerson, Matthew; Zhang, Cheng-Zhong; Imielinski, Marcin; Beroukhim, Rameen

2018-04-01

Structural variants (SVs), including small insertion and deletion variants (indels), are challenging to detect through standard alignment-based variant calling methods. Sequence assembly offers a powerful approach to identifying SVs, but is difficult to apply at scale genome-wide for SV detection due to its computational complexity and the difficulty of extracting SVs from assembly contigs. We describe SvABA, an efficient and accurate method for detecting SVs from short-read sequencing data using genome-wide local assembly with low memory and computing requirements. We evaluated SvABA's performance on the NA12878 human genome and in simulated and real cancer genomes. SvABA demonstrates superior sensitivity and specificity across a large spectrum of SVs and substantially improves detection performance for variants in the 20-300 bp range, compared with existing methods. SvABA also identifies complex somatic rearrangements with chains of short (<1000 bp) templated-sequence insertions copied from distant genomic regions. We applied SvABA to 344 cancer genomes from 11 cancer types and found that short templated-sequence insertions occur in ∼4% of all somatic rearrangements. Finally, we demonstrate that SvABA can identify sites of viral integration and cancer driver alterations containing medium-sized (50-300 bp) SVs. © 2018 Wala et al.; Published by Cold Spring Harbor Laboratory Press.

Left Superior Vena Cava Draining Into Left Atrium in Tetralogy of Fallot-Four Cases of a Rare Association.

PubMed

Ramman, Tarun Raina; Dutta, Nilanjan; Chowdhuri, Kuntal Roy; Agrawal, Sunny; Girotra, Sumir; Azad, Sushil; Radhakrishnan, Sitaraman; Iyer, Parvathi Unninayar; Iyer, Krishna Subramony

2018-01-01

Persistent left superior vena cava is a common congenital anomaly of the thoracic venous system. Left superior vena cava draining into left atrium is a malformation of sinus venosus and caval system. The anomaly may be a cause of unexplained hypoxia even in adults. It may give rise to various diagnostic and technical challenges during cardiac catheterization and open-heart surgery. It is often detected serendipitously during diagnostic workup. Isolated left superior vena cava opening into left atrium is very commonly associated with other congenital heart defects. But tetralogy of Fallot is very rarely associated with persistent left superior vena cava which drains into left atrium. We report four such cases who underwent surgical correction successfully.

Visual search performance in infants associates with later ASD diagnosis.

PubMed

Cheung, C H M; Bedford, R; Johnson, M H; Charman, T; Gliga, T

2018-01-01

An enhanced ability to detect visual targets amongst distractors, known as visual search (VS), has often been documented in Autism Spectrum Disorders (ASD). Yet, it is unclear when this behaviour emerges in development and if it is specific to ASD. We followed up infants at high and low familial risk for ASD to investigate how early VS abilities links to later ASD diagnosis, the potential underlying mechanisms of this association and the specificity of superior VS to ASD. Clinical diagnosis of ASD as well as dimensional measures of ASD, attention-deficit/hyperactivity disorder (ADHD) and anxiety symptoms were ascertained at 3 years. At 9 and 15 months, but not at age 2 years, high-risk children who later met clinical criteria for ASD (HR-ASD) had better VS performance than those without later diagnosis and low-risk controls. Although HR-ASD children were also more attentive to the task at 9 months, this did not explain search performance. Superior VS specifically predicted 3 year-old ASD but not ADHD or anxiety symptoms. Our results demonstrate that atypical perception and core ASD symptoms of social interaction and communication are closely and selectively associated during early development, and suggest causal links between perceptual and social features of ASD. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

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...

Whole-body low-dose computed tomography in multiple myeloma staging: Superior diagnostic performance in the detection of bone lesions, vertebral compression fractures, rib fractures and extraskeletal findings compared to radiography with similar radiation exposure.

PubMed

Lambert, Lukas; Ourednicek, Petr; Meckova, Zuzana; Gavelli, Giampaolo; Straub, Jan; Spicka, Ivan

2017-04-01

The primary objective of the present prospective study was to compare the diagnostic performance of conventional radiography (CR) and whole-body low-dose computed tomography (WBLDCT) with a comparable radiation dose reconstructed using hybrid iterative reconstruction technique, in terms of the detection of bone lesions, skeletal fractures, vertebral compressions and extraskeletal findings. The secondary objective was to evaluate lesion attenuation in relation to its size. A total of 74 patients underwent same-day skeletal survey by CR and WBLDCT. In CR and WBLDCT, two readers assessed the number of osteolytic lesions at each region and stage according to the International Myeloma Working Group (IMWG) criteria. A single reader additionally assessed extraskeletal findings and their significance, the number of vertebral compressions and bone fractures. The radiation exposure was 2.7±0.9 mSv for WBLDCT and 2.5±0.9 mSv for CR (P=0.054). CR detected bone involvement in 127 out of 486 regions (26%; P<0.0001), confirmed by WBLDCT. CR underestimated the disease stage in 16% and overestimated it in 8% of the patients (P=0.0077). WBLDCT detected more rib fractures compared with CR (188 vs. 47; P<0.0001), vertebral compressions (93 vs. 67; P=0.010) and extraskeletal findings (194 vs. 52; P<0.0001). There was no correlation observed between lesion size (≥5 mm) and its attenuation (r=-0.006; P=0.93). The inter-observer agreement for the presence of osteolytic lesions was κ=0.76 for WBLDCT, and κ=0.55 for CR. The present study concluded that WBLDCT with hybrid iterative reconstruction technique demonstrates superiority to CR with an identical radiation dose in the detection of bone lesions, skeletal fractures, vertebral compressions and extraskeletal findings, which results in up- or downstaging in 24% patients according to the IMWG criteria. The attenuation of osteolytic lesions can be measured with the avoidance of the partial volume effect.

Controversies in colorectal cancer screening.

PubMed

Pox, Christian P

2014-01-01

Colorectal cancer (CRC) is one of the most common cancers worldwide and a good candidate for screening programmes. However, there is controversy concerning which of the available screening tests should be used. There is general agreement that screening for CRC in the asymptomatic population should begin at the age of 50. Several different screening methods are available which can be separated into those that mainly detect cancers: faecal occult blood tests [guaiac (FOBT) and immunochemical (FIT)], genetic stool tests, blood tests and the M2-pyruvate kinase (M2-PK) test. Methods that detect cancers and polyps are colonoscopy, sigmoidoscopy, CT-colonography (CT-C) and colon capsule endoscopy. The only tests for which a reduction in CRC mortality compared to no screening have been proven in randomized trials are FOBT and sigmoidoscopy. Several trials suggest that FIT are superior to FOBT in terms of detection rates of cancers and advanced adenomas and possibly compliance. There is indirect evidence suggesting efficacy of colonoscopy as a screening test. The role of CT-C is controversial. There is data suggesting a good sensitivity for neoplasia >9 mm with a lower sensitivity for smaller neoplasia. However, radiation exposure is considered a major limitation in some countries. Unresolved questions include the lesion cut-off for referral to colonoscopy and work-up of extracolonic findings. For other methods, like genetic stool testing using newer markers, blood tests, capsule endoscopy and M2-PK, there is currently insufficient data on screening of the asymptomatic population. Key Messages: Colorectal screening is recommended and should be performed in the form of an organized programme. If detection of early-stage cancers is the aim of a screening programme, FIT seem to be superior to FOBT. If detection and removal of adenomas is the aim of a screening programme, endoscopic methods seem to be good alternatives. Sigmoidoscopy is easier to perform but will likely only have an effect on distal cancers. Colonoscopy is more invasive but enables inspection of the whole colon. The role of CT-C, capsule endoscopy, genetic stool tests, blood tests and M2-PK is currently unknown. © 2014 S. Karger AG, Basel.

A self-assembled fluorescent organic nanoprobe and its application for sulfite detection in food samples and living systems.

PubMed

Gao, Tang; Cao, Xiaozheng; Ge, Peng; Dong, Jie; Yang, Shuqi; Xu, Huan; Wu, Yong; Gao, Feng; Zeng, Wenbin

2017-05-23

Sulfur dioxide (SO 2 ) is a widely distributed air pollutant, and humans can easily be exposed to sulfite by inhaling SO 2 , thus inducing respiratory responses and diseases. Hence, to develop a rapid, sensitive and selective method for detection of sulfites is of great importance. Herein, we designed and synthesized a novel tetraphenyl imidazole compound TIBM with aggregation-induced emission enhancement (AIEE). TIBM can self-assemble into well-organized nanoparticles and is reported as an excellent probe for detection of sulfite with high selectivity and sensitivity. The nanoprobe performed very well for the detection of sulfite with an ultrafast detection time (15 s) and an ultralow detection limit (7.4 nM), which is superior to most of the reported probes. Moreover, the nanoprobe was successfully used to detect sulfite in food samples with a favorable accuracy. In addition, we developed paper-based devices for point-of-care detection of sulfite with naked eyes. Furthermore, due to its high water solubility, cell membrane permeability and good biocompatibility, the nanoproboe was further applied to detect sulfite in living systems. This study may offer some helpful insights for designing other AIE-based fluorescent nanosensors for various analytes.

Development of a comprehensive performance-testing protocol for competitive surfers.

PubMed

Sheppard, Jeremy M; Nimphius, Sophia; Haff, Greg G; Tran, Tai T; Spiteri, Tania; Brooks, Hedda; Slater, Gary; Newton, Robert U

2013-09-01

Appropriate and valid testing protocols for evaluating the physical performances of surfing athletes are not well refined. The purpose of this project was to develop, refine, and evaluate a testing protocol for use with elite surfers, including measures of anthropometry, strength and power, and endurance. After pilot testing and consultation with athletes, coaches, and sport scientists, a specific suite of tests was developed. Forty-four competitive junior surfers (16.2 ± 1.3 y, 166.3 ± 7.3 cm, 57.9 ± 8.5 kg) participated in this study involving a within-day repeated-measures analysis, using an elite junior group of 22 international competitors (EJG), to establish reliability of the measures. To reflect validity of the testing measures, a comparison of performance results was then undertaken between the EJG and an age-matched competitive junior group of 22 nationally competitive surfers (CJG). Percent typical error of measurement (%TEM) for primary variables gained from the assessments ranged from 1.1% to 3.0%, with intraclass correlation coefficients ranging from .96 to .99. One-way analysis of variance revealed that the EJG had lower skinfolds (P = .005, d = 0.9) than the CJG, despite no difference in stature (P = .102) or body mass (P = .827). The EJG were faster in 15-m sprint-paddle velocity (P < .001, d = 1.3) and had higher lower-body isometric peak force (P = .04, d = 0.7) and superior endurance-paddling velocity (P = .008, d = 0.9). The relatively low %TEM of these tests in this population allows for high sensitivity to detect change. The results of this study suggest that competitively superior junior surfers are leaner and possess superior strength, paddling power, and paddling endurance.

Evolutionary neural networks for anomaly detection based on the behavior of a program.

PubMed

Han, Sang-Jun; Cho, Sung-Bae

2006-06-01

The process of learning the behavior of a given program by using machine-learning techniques (based on system-call audit data) is effective to detect intrusions. Rule learning, neural networks, statistics, and hidden Markov models (HMMs) are some of the kinds of representative methods for intrusion detection. Among them, neural networks are known for good performance in learning system-call sequences. In order to apply this knowledge to real-world problems successfully, it is important to determine the structures and weights of these call sequences. However, finding the appropriate structures requires very long time periods because there are no suitable analytical solutions. In this paper, a novel intrusion-detection technique based on evolutionary neural networks (ENNs) is proposed. One advantage of using ENNs is that it takes less time to obtain superior neural networks than when using conventional approaches. This is because they discover the structures and weights of the neural networks simultaneously. Experimental results with the 1999 Defense Advanced Research Projects Agency (DARPA) Intrusion Detection Evaluation (IDEVAL) data confirm that ENNs are promising tools for intrusion detection.

A Hybrid Color Space for Skin Detection Using Genetic Algorithm Heuristic Search and Principal Component Analysis Technique

PubMed Central

2015-01-01

Color is one of the most prominent features of an image and used in many skin and face detection applications. Color space transformation is widely used by researchers to improve face and skin detection performance. Despite the substantial research efforts in this area, choosing a proper color space in terms of skin and face classification performance which can address issues like illumination variations, various camera characteristics and diversity in skin color tones has remained an open issue. This research proposes a new three-dimensional hybrid color space termed SKN by employing the Genetic Algorithm heuristic and Principal Component Analysis to find the optimal representation of human skin color in over seventeen existing color spaces. Genetic Algorithm heuristic is used to find the optimal color component combination setup in terms of skin detection accuracy while the Principal Component Analysis projects the optimal Genetic Algorithm solution to a less complex dimension. Pixel wise skin detection was used to evaluate the performance of the proposed color space. We have employed four classifiers including Random Forest, Naïve Bayes, Support Vector Machine and Multilayer Perceptron in order to generate the human skin color predictive model. The proposed color space was compared to some existing color spaces and shows superior results in terms of pixel-wise skin detection accuracy. Experimental results show that by using Random Forest classifier, the proposed SKN color space obtained an average F-score and True Positive Rate of 0.953 and False Positive Rate of 0.0482 which outperformed the existing color spaces in terms of pixel wise skin detection accuracy. The results also indicate that among the classifiers used in this study, Random Forest is the most suitable classifier for pixel wise skin detection applications. PMID:26267377

DEWS (DEep White matter hyperintensity Segmentation framework): A fully automated pipeline for detecting small deep white matter hyperintensities in migraineurs.

PubMed

Park, Bo-Yong; Lee, Mi Ji; Lee, Seung-Hak; Cha, Jihoon; Chung, Chin-Sang; Kim, Sung Tae; Park, Hyunjin

2018-01-01

Migraineurs show an increased load of white matter hyperintensities (WMHs) and more rapid deep WMH progression. Previous methods for WMH segmentation have limited efficacy to detect small deep WMHs. We developed a new fully automated detection pipeline, DEWS (DEep White matter hyperintensity Segmentation framework), for small and superficially-located deep WMHs. A total of 148 non-elderly subjects with migraine were included in this study. The pipeline consists of three components: 1) white matter (WM) extraction, 2) WMH detection, and 3) false positive reduction. In WM extraction, we adjusted the WM mask to re-assign misclassified WMHs back to WM using many sequential low-level image processing steps. In WMH detection, the potential WMH clusters were detected using an intensity based threshold and region growing approach. For false positive reduction, the detected WMH clusters were classified into final WMHs and non-WMHs using the random forest (RF) classifier. Size, texture, and multi-scale deep features were used to train the RF classifier. DEWS successfully detected small deep WMHs with a high positive predictive value (PPV) of 0.98 and true positive rate (TPR) of 0.70 in the training and test sets. Similar performance of PPV (0.96) and TPR (0.68) was attained in the validation set. DEWS showed a superior performance in comparison with other methods. Our proposed pipeline is freely available online to help the research community in quantifying deep WMHs in non-elderly adults.

Biomechanical Effects of Acromioplasty on Superior Capsule Reconstruction for Irreparable Supraspinatus Tendon Tears.

PubMed

Mihata, Teruhisa; McGarry, Michelle H; Kahn, Timothy; Goldberg, Iliya; Neo, Masashi; Lee, Thay Q

2016-01-01

Acromioplasty is increasingly being performed for both reparable and irreparable rotator cuff tears. However, acromioplasty may destroy the coracoacromial arch, including the coracoacromial ligament, consequently causing a deterioration in superior stability even after superior capsule reconstruction. The purpose of this study was to investigate the effects of acromioplasty on shoulder biomechanics after superior capsule reconstruction for irreparable supraspinatus tendon tears. The hypothesis was that acromioplasty with superior capsule reconstruction would decrease the area of subacromial impingement without increasing superior translation and subacromial contact pressure. Controlled laboratory study. Seven fresh-frozen cadaveric shoulders were evaluated using a custom shoulder testing system. Glenohumeral superior translation, the location of the humeral head relative to the glenoid, and subacromial contact pressure and area were compared among 4 conditions: (1) intact shoulder, (2) irreparable supraspinatus tendon tear, (3) superior capsule reconstruction without acromioplasty, and (4) superior capsule reconstruction with acromioplasty. Superior capsule reconstruction was performed using the fascia lata. Compared with the intact shoulder, the creation of an irreparable supraspinatus tear significantly shifted the humeral head superiorly in the balanced muscle loading condition (without superior force applied) (0° of abduction: 2.8-mm superior shift [P = .0005]; 30° of abduction: 1.9-mm superior shift [P = .003]) and increased both superior translation (0° of abduction: 239% of intact [P = .04]; 30° of abduction: 199% of intact [P = .02]) and subacromial peak contact pressure (0° of abduction: 308% of intact [P = .0002]; 30° of abduction: 252% of intact [P = .001]) by applying superior force. Superior capsule reconstruction without acromioplasty significantly decreased superior translation (0° of abduction: 86% of intact [P = .02]; 30° of abduction: 75% of intact [P = .002]) and subacromial peak contact pressure (0° of abduction: 47% of intact [P = .0002]; 30° of abduction: 83% of intact [P = .0005]; 60° of abduction: 38% of intact [P = .04]) compared with after the creation of a supraspinatus tear. Adding acromioplasty significantly decreased the subacromial contact area compared with superior capsule reconstruction without acromioplasty (0° of abduction: 26% decrease [P = .01]; 30° of abduction: 21% decrease [P = .009]; 60° of abduction: 61% decrease [P = .003]) and did not alter humeral head position, superior translation, or subacromial peak contact pressure. Superior capsule reconstruction repositioned the superiorly migrated humeral head and restored superior stability in the shoulder joint. Adding acromioplasty decreased the subacromial contact area without increasing the subacromial contact pressure. When superior capsule reconstruction is performed for irreparable rotator cuff tears, acromioplasty may help to decrease the postoperative risk of abrasion and tearing of the graft beneath the acromion. © 2015 The Author(s).

Individual differences in working memory capacity and workload capacity.

PubMed

Yu, Ju-Chi; Chang, Ting-Yun; Yang, Cheng-Ta

2014-01-01

We investigated the relationship between working memory capacity (WMC) and workload capacity (WLC). Each participant performed an operation span (OSPAN) task to measure his/her WMC and three redundant-target detection tasks to measure his/her WLC. WLC was computed non-parametrically (Experiments 1 and 2) and parametrically (Experiment 2). Both levels of analyses showed that participants high in WMC had larger WLC than those low in WMC only when redundant information came from visual and auditory modalities, suggesting that high-WMC participants had superior processing capacity in dealing with redundant visual and auditory information. This difference was eliminated when multiple processes required processing for only a single working memory subsystem in a color-shape detection task and a double-dot detection task. These results highlighted the role of executive control in integrating and binding information from the two working memory subsystems for perceptual decision making.

Enclosure Transform for Interest Point Detection From Speckle Imagery.

PubMed

Yongjian Yu; Jue Wang

2017-03-01

We present a fast enclosure transform (ET) to localize complex objects of interest from speckle imagery. This approach explores the spatial confinement on regional features from a sparse image feature representation. Unrelated, broken ridge features surrounding an object are organized collaboratively, giving rise to the enclosureness of the object. Three enclosure likelihood measures are constructed, consisting of the enclosure force, potential energy, and encloser count. In the transform domain, the local maxima manifest the locations of objects of interest, for which only the intrinsic dimension is known a priori. The discrete ET algorithm is computationally efficient, being on the order of O(MN) using N measuring distances across an image of M ridge pixels. It involves easy and few parameter settings. We demonstrate and assess the performance of ET on the automatic detection of the prostate locations from supra-pubic ultrasound images. ET yields superior results in terms of positive detection rate, accuracy and coverage.

Waveguide integrated superconducting single-photon detectors with high internal quantum efficiency at telecom wavelengths

PubMed Central

Kahl, Oliver; Ferrari, Simone; Kovalyuk, Vadim; Goltsman, Gregory N.; Korneev, Alexander; Pernice, Wolfram H. P.

2015-01-01

Superconducting nanowire single-photon detectors (SNSPDs) provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, compatibility with an integrated optical platform is a crucial requirement for applications in emerging quantum photonic technologies. Here we present SNSPDs embedded in nanophotonic integrated circuits which achieve internal quantum efficiencies close to unity at 1550 nm wavelength. This allows for the SNSPDs to be operated at bias currents far below the critical current where unwanted dark count events reach milli-Hz levels while on-chip detection efficiencies above 70% are maintained. The measured dark count rates correspond to noise-equivalent powers in the 10−19 W/Hz−1/2 range and the timing jitter is as low as 35 ps. Our detectors are fully scalable and interface directly with waveguide-based optical platforms. PMID:26061283

Waveguide integrated superconducting single-photon detectors with high internal quantum efficiency at telecom wavelengths.

PubMed

Kahl, Oliver; Ferrari, Simone; Kovalyuk, Vadim; Goltsman, Gregory N; Korneev, Alexander; Pernice, Wolfram H P

2015-06-10

Superconducting nanowire single-photon detectors (SNSPDs) provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, compatibility with an integrated optical platform is a crucial requirement for applications in emerging quantum photonic technologies. Here we present SNSPDs embedded in nanophotonic integrated circuits which achieve internal quantum efficiencies close to unity at 1550 nm wavelength. This allows for the SNSPDs to be operated at bias currents far below the critical current where unwanted dark count events reach milli-Hz levels while on-chip detection efficiencies above 70% are maintained. The measured dark count rates correspond to noise-equivalent powers in the 10(-19) W/Hz(-1/2) range and the timing jitter is as low as 35 ps. Our detectors are fully scalable and interface directly with waveguide-based optical platforms.

Community detection in complex networks by using membrane algorithm

NASA Astrophysics Data System (ADS)

Liu, Chuang; Fan, Linan; Liu, Zhou; Dai, Xiang; Xu, Jiamei; Chang, Baoren

Community detection in complex networks is a key problem of network analysis. In this paper, a new membrane algorithm is proposed to solve the community detection in complex networks. The proposed algorithm is based on membrane systems, which consists of objects, reaction rules, and a membrane structure. Each object represents a candidate partition of a complex network, and the quality of objects is evaluated according to network modularity. The reaction rules include evolutionary rules and communication rules. Evolutionary rules are responsible for improving the quality of objects, which employ the differential evolutionary algorithm to evolve objects. Communication rules implement the information exchanged among membranes. Finally, the proposed algorithm is evaluated on synthetic, real-world networks with real partitions known and the large-scaled networks with real partitions unknown. The experimental results indicate the superior performance of the proposed algorithm in comparison with other experimental algorithms.

A Widely Applicable Silver Sol for TLC Detection with Rich and Stable SERS Features.

PubMed

Zhu, Qingxia; Li, Hao; Lu, Feng; Chai, Yifeng; Yuan, Yongfang

2016-12-01

Thin-layer chromatography (TLC) coupled with surface-enhanced Raman spectroscopy (SERS) has gained tremendous popularity in the study of various complex systems. However, the detection of hydrophobic analytes is difficult, and the specificity still needs to be improved. In this study, a SERS-active non-aqueous silver sol which could activate the analytes to produce rich and stable spectral features was rapidly synthesized. Then, the optimized silver nanoparticles (AgNPs)-DMF sol was employed for TLC-SERS detection of hydrophobic (and also hydrophilic) analytes. SERS performance of this sol was superior to that of traditional Lee-Meisel AgNPs due to its high specificity, acceptable stability, and wide applicability. The non-aqueous AgNPs would be suitable for the TLC-SERS method, which shows great promise for applications in food safety assurance, environmental monitoring, medical diagnoses, and many other fields.

A Widely Applicable Silver Sol for TLC Detection with Rich and Stable SERS Features

NASA Astrophysics Data System (ADS)

Zhu, Qingxia; Li, Hao; Lu, Feng; Chai, Yifeng; Yuan, Yongfang

2016-04-01

Thin-layer chromatography (TLC) coupled with surface-enhanced Raman spectroscopy (SERS) has gained tremendous popularity in the study of various complex systems. However, the detection of hydrophobic analytes is difficult, and the specificity still needs to be improved. In this study, a SERS-active non-aqueous silver sol which could activate the analytes to produce rich and stable spectral features was rapidly synthesized. Then, the optimized silver nanoparticles (AgNPs)-DMF sol was employed for TLC-SERS detection of hydrophobic (and also hydrophilic) analytes. SERS performance of this sol was superior to that of traditional Lee-Meisel AgNPs due to its high specificity, acceptable stability, and wide applicability. The non-aqueous AgNPs would be suitable for the TLC-SERS method, which shows great promise for applications in food safety assurance, environmental monitoring, medical diagnoses, and many other fields.

PdCuPt Nanocrystals With Multi-branches for Enzyme-free Glucose Detection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fu, Shaofang; Zhu, Chengzhou; Song, Junhua

By carefully controlling the synthesis condition, branched PtCu bimetallic templates were synthesized in aqueous solution. After the galvanic replacement reaction between PtCu templates and the Pt precursors, PdCuPt trimetallic nanocrystals with branched structures were obtained. Owing to the open structure and the optimized composition, the electrochemical experimental results reveal that the PdCuPt trimetallic nanocrystals exhibit high electrocatalytic activity, selectivity and stability for the oxidation of glucose in alkaline solution. In details, a sensitivity of 378 μA/mM/cm2 and a detection limit of 1.29 μM can be achieved. The good electrocatalytic performance should be attributed to the unique branched nanostructure as wellmore » as the synergistic effect among metals. The superior catalytic properties suggest that these nanocrystals are promising for enzyme-free detection of glucose.« less

Weak Fault Feature Extraction of Rolling Bearings Based on an Improved Kurtogram.

PubMed

Chen, Xianglong; Feng, Fuzhou; Zhang, Bingzhi

2016-09-13

Kurtograms have been verified to be an efficient tool in bearing fault detection and diagnosis because of their superiority in extracting transient features. However, the short-time Fourier Transform is insufficient in time-frequency analysis and kurtosis is deficient in detecting cyclic transients. Those factors weaken the performance of the original kurtogram in extracting weak fault features. Correlated Kurtosis (CK) is then designed, as a more effective solution, in detecting cyclic transients. Redundant Second Generation Wavelet Packet Transform (RSGWPT) is deemed to be effective in capturing more detailed local time-frequency description of the signal, and restricting the frequency aliasing components of the analysis results. The authors in this manuscript, combining the CK with the RSGWPT, propose an improved kurtogram to extract weak fault features from bearing vibration signals. The analysis of simulation signals and real application cases demonstrate that the proposed method is relatively more accurate and effective in extracting weak fault features.

Microstructured silicon neutron detectors for security applications

NASA Astrophysics Data System (ADS)

Esteban, S.; Fleta, C.; Guardiola, C.; Jumilla, C.; Pellegrini, G.; Quirion, D.; Rodriguez, J.; Lozano, M.

2014-12-01

In this paper we present the design and performance of a perforated thermal neutron silicon detector with a 6LiF neutron converter. This device was manufactured within the REWARD project workplace whose aim is to develop and enhance technologies for the detection of nuclear and radiological materials. The sensor perforated structure results in a higher efficiency than that obtained with an equivalent planar sensor. The detectors were tested in a thermal neutron beam at the nuclear reactor at the Instituto Superior Técnico in Lisbon and the intrinsic detection efficiency for thermal neutrons and the gamma sensitivity were obtained. The Geant4 Monte Carlo code was used to simulate the experimental conditions, i.e. thermal neutron beam and the whole detector geometry. An intrinsic thermal neutron detection efficiency of 8.6%±0.4% with a discrimination setting of 450 keV was measured.

Evaluation of Two Commercial Enzyme-Linked Immunosorbent Assay Kits for the Detection of Human Circulating Metrnl.

PubMed

Zheng, Si-Li; Li, Zhi-Yong; Zhang, Zheng; Wang, Dong-Sheng; Xu, Jian; Miao, Chao-Yu

2018-04-01

Metrnl is a newly discovered secreted protein with neurotrophic activity and metabolic effect, while in earlier studies its circulating level in human was not explored. We evaluated two commercial enzyme-linked immunosorbent assay kits (DY7867-05, R&D Systems and SK00478-02, Aviscera Bioscience) for the detection of human circulating Metrnl. The DY7867-05 kit showed superiority over the SK00478-02 kit since it generated better curve fitting degree, smaller variation among tests, higher inter-assay reproducibility and better specificity, and could effectively detect human Metrnl in six types of blood samples. Subsequent analysis was performed using the DY7867-05 kit. Sample storage conditions were investigated. No gender difference in circulating Metrnl levels was found, while people with newly diagnosed type 2 diabetes mellitus (T2DM) had significantly lower Metrnl levels compared to the healthy controls.

Intrinsic resting-state activity predicts working memory brain activation and behavioral performance.

PubMed

Zou, Qihong; Ross, Thomas J; Gu, Hong; Geng, Xiujuan; Zuo, Xi-Nian; Hong, L Elliot; Gao, Jia-Hong; Stein, Elliot A; Zang, Yu-Feng; Yang, Yihong

2013-12-01

Although resting-state brain activity has been demonstrated to correspond with task-evoked brain activation, the relationship between intrinsic and evoked brain activity has not been fully characterized. For example, it is unclear whether intrinsic activity can also predict task-evoked deactivation and whether the rest-task relationship is dependent on task load. In this study, we addressed these issues on 40 healthy control subjects using resting-state and task-driven [N-back working memory (WM) task] functional magnetic resonance imaging data collected in the same session. Using amplitude of low-frequency fluctuation (ALFF) as an index of intrinsic resting-state activity, we found that ALFF in the middle frontal gyrus and inferior/superior parietal lobules was positively correlated with WM task-evoked activation, while ALFF in the medial prefrontal cortex, posterior cingulate cortex, superior frontal gyrus, superior temporal gyrus, and fusiform gyrus was negatively correlated with WM task-evoked deactivation. Further, the relationship between the intrinsic resting-state activity and task-evoked activation in lateral/superior frontal gyri, inferior/superior parietal lobules, superior temporal gyrus, and midline regions was stronger at higher WM task loads. In addition, both resting-state activity and the task-evoked activation in the superior parietal lobule/precuneus were significantly correlated with the WM task behavioral performance, explaining similar portions of intersubject performance variance. Together, these findings suggest that intrinsic resting-state activity facilitates or is permissive of specific brain circuit engagement to perform a cognitive task, and that resting activity can predict subsequent task-evoked brain responses and behavioral performance. Copyright © 2012 Wiley Periodicals, Inc.

The influence of working memory on the anger superiority effect.

PubMed

Moriya, Jun; Koster, Ernst H W; De Raedt, Rudi

2014-01-01

The anger superiority effect shows that an angry face is detected more efficiently than a happy face. However, it is still controversial whether attentional allocation to angry faces is a bottom-up process or not. We investigated whether the anger superiority effect is influenced by top-down control, especially working memory (WM). Participants remembered a colour and then searched for differently coloured facial expressions. Just holding the colour information in WM did not modulate the anger superiority effect. However, when increasing the probabilities of trials in which the colour of a target face matched the colour held in WM, participants were inclined to direct attention to the target face regardless of the facial expression. Moreover, the knowledge of high probability of valid trials eliminated the anger superiority effect. These results suggest that the anger superiority effect is modulated by top-down effects of WM, the probability of events and expectancy about these probabilities.

Experimental Study on Damage Detection in Timber Specimens Based on an Electromechanical Impedance Technique and RMSD-Based Mahalanobis Distance

PubMed Central

Wang, Dansheng; Wang, Qinghua; Wang, Hao; Zhu, Hongping

2016-01-01

In the electromechanical impedance (EMI) method, the PZT patch performs the functions of both sensor and exciter. Due to the high frequency actuation and non-model based characteristics, the EMI method can be utilized to detect incipient structural damage. In recent years EMI techniques have been widely applied to monitor the health status of concrete and steel materials, however, studies on application to timber are limited. This paper will explore the feasibility of using the EMI technique for damage detection in timber specimens. In addition, the conventional damage index, namely root mean square deviation (RMSD) is employed to evaluate the level of damage. On that basis, a new damage index, Mahalanobis distance based on RMSD, is proposed to evaluate the damage severity of timber specimens. Experimental studies are implemented to detect notch and hole damage in the timber specimens. Experimental results verify the availability and robustness of the proposed damage index and its superiority over the RMSD indexes. PMID:27782088

Experimental Study on Damage Detection in Timber Specimens Based on an Electromechanical Impedance Technique and RMSD-Based Mahalanobis Distance.

PubMed

Wang, Dansheng; Wang, Qinghua; Wang, Hao; Zhu, Hongping

2016-10-22

In the electromechanical impedance (EMI) method, the PZT patch performs the functions of both sensor and exciter. Due to the high frequency actuation and non-model based characteristics, the EMI method can be utilized to detect incipient structural damage. In recent years EMI techniques have been widely applied to monitor the health status of concrete and steel materials, however, studies on application to timber are limited. This paper will explore the feasibility of using the EMI technique for damage detection in timber specimens. In addition, the conventional damage index, namely root mean square deviation (RMSD) is employed to evaluate the level of damage. On that basis, a new damage index, Mahalanobis distance based on RMSD, is proposed to evaluate the damage severity of timber specimens. Experimental studies are implemented to detect notch and hole damage in the timber specimens. Experimental results verify the availability and robustness of the proposed damage index and its superiority over the RMSD indexes.

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…

Imaging and Detection of Carboxylesterase in Living Cells and Zebrafish Pretreated with Pesticides by a New Near-Infrared Fluorescence Off-On Probe.

PubMed

Li, Dongyu; Li, Zhao; Chen, Weihua; Yang, Xingbin

2017-05-24

A new near-infrared fluorescence off-on probe was developed and applied to fluorescence imaging of carboxylesterase in living HepG-2 cells and zebrafish pretreated with pesticides (carbamate, organophosphorus, and pyrethroid). The probe was readily prepared by connecting (4-acetoxybenzyl)oxy as a quenching and recognizing moiety to a stable hemicyanine skeleton that can be formed via the decomposition of IR-780. The fluorescence off-on response of the probe to carboxylesterase is based on the enzyme-catalyzed spontaneous hydrolysis of the carboxylic ester bond, followed by a further fragmentation of the phenylmethyl unit and thereby the fluorophore release. Compared with the only existing near-infrared carboxylesterase probe, the proposed probe exhibits superior analytical performance, such as near-infrared fluorescence emission over 700 nm as well as high selectivity and sensitivity, with a detection limit of 4.5 × 10 -3 U/mL. More importantly, the probe is cell membrane permeable, and its applicability has been successfully demonstrated for monitoring carboxylesterase activity in living HepG-2 cells and zebrafish pretreated with pesticides, revealing that pesticides can effectively inhibit the activity of carboxylesterase. The superior properties of the probe make it of great potential use in indicating pesticide exposure.

Revising superior planning performance in chess players: the impact of time restriction and motivation aspects.

PubMed

Unterrainer, Josef Martin; Kaller, Christoph Philipp; Leonhart, Rainer; Rahm, Benjamin

2011-01-01

In a previous study (Unterrainer, Kaller, Halsband, & Rahm, 2006), chess players outperformed non-chess players in the Tower of London planning task but exhibited disproportionately longer processing times. This pattern of results raises the question of whether chess players' planning capabilities are superior or whether the results reflect differences in the speed-accuracy trade-off between the groups, possibly attributable to sports motivation. The present study was designed to disambiguate these alternative suggestions by implementing various constraints on planning time and by assessing self-reported motivation. In contrast to the previous study, chess players' performance was not superior, independently of whether problems had to be solved with (Experiment 1) or without (Experiment 2) time limits. As expected, chess players reported higher overall trait and state motivation scores across both experiments. These findings revise the notion of superior planning performance in chess players. In consequence, they do not conform with the assumption of a general transfer of chess-related planning expertise to other cognitive domains, instead suggesting that superior performance may be possible only under specific circumstances such as receiving competitive instructions.

Comparable cortical activation with inferior performance in women during a novel cognitive inhibition task.

PubMed

Halari, R; Kumari, V

2005-03-07

Men are hypothesised to perform better than women at tasks requiring cognitive inhibition. The present study applied whole-brain functional magnetic resonance imaging to investigate the neural correlates of cognitive inhibition using a novel task, requiring detection of numbers decreasing in numerical order, in relation to sex. The study involved 19 young healthy subjects (9 men, 10 women). Behavioural sex differences favouring men were found on the inhibition, but not on the automatization (i.e. detection of numbers increasing in numerical order), condition of the task. Significant areas of activation associated with cognitive inhibition included the right inferior prefrontal and bilateral dorsolateral prefrontal cortices, left inferior and superior parietal lobes, and bilateral temporal regions across men and women. No brain region was significantly differently activated in men and women. Our findings demonstrate that (a) cognitive inhibition is dependent on intact processes within frontal and parietal regions, and (b) women show inferior cognitive inhibition despite of comparable activation to men in relevant regions. Equated behavioural performance may elicit sex differences in brain activation.

Minimum entropy deconvolution optimized sinusoidal synthesis and its application to vibration based fault detection

NASA Astrophysics Data System (ADS)

Li, Gang; Zhao, Qing

2017-03-01

In this paper, a minimum entropy deconvolution based sinusoidal synthesis (MEDSS) filter is proposed to improve the fault detection performance of the regular sinusoidal synthesis (SS) method. The SS filter is an efficient linear predictor that exploits the frequency properties during model construction. The phase information of the harmonic components is not used in the regular SS filter. However, the phase relationships are important in differentiating noise from characteristic impulsive fault signatures. Therefore, in this work, the minimum entropy deconvolution (MED) technique is used to optimize the SS filter during the model construction process. A time-weighted-error Kalman filter is used to estimate the MEDSS model parameters adaptively. Three simulation examples and a practical application case study are provided to illustrate the effectiveness of the proposed method. The regular SS method and the autoregressive MED (ARMED) method are also implemented for comparison. The MEDSS model has demonstrated superior performance compared to the regular SS method and it also shows comparable or better performance with much less computational intensity than the ARMED method.

Investigation of statistical iterative reconstruction for dedicated breast CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makeev, Andrey; Glick, Stephen J.

2013-08-15

Purpose: Dedicated breast CT has great potential for improving the detection and diagnosis of breast cancer. Statistical iterative reconstruction (SIR) in dedicated breast CT is a promising alternative to traditional filtered backprojection (FBP). One of the difficulties in using SIR is the presence of free parameters in the algorithm that control the appearance of the resulting image. These parameters require tuning in order to achieve high quality reconstructions. In this study, the authors investigated the penalized maximum likelihood (PML) method with two commonly used types of roughness penalty functions: hyperbolic potential and anisotropic total variation (TV) norm. Reconstructed images weremore » compared with images obtained using standard FBP. Optimal parameters for PML with the hyperbolic prior are reported for the task of detecting microcalcifications embedded in breast tissue.Methods: Computer simulations were used to acquire projections in a half-cone beam geometry. The modeled setup describes a realistic breast CT benchtop system, with an x-ray spectra produced by a point source and an a-Si, CsI:Tl flat-panel detector. A voxelized anthropomorphic breast phantom with 280 μm microcalcification spheres embedded in it was used to model attenuation properties of the uncompressed woman's breast in a pendant position. The reconstruction of 3D images was performed using the separable paraboloidal surrogates algorithm with ordered subsets. Task performance was assessed with the ideal observer detectability index to determine optimal PML parameters.Results: The authors' findings suggest that there is a preferred range of values of the roughness penalty weight and the edge preservation threshold in the penalized objective function with the hyperbolic potential, which resulted in low noise images with high contrast microcalcifications preserved. In terms of numerical observer detectability index, the PML method with optimal parameters yielded substantially improved performance (by a factor of greater than 10) compared to FBP. The hyperbolic prior was also observed to be superior to the TV norm. A few of the best-performing parameter pairs for the PML method also demonstrated superior performance for various radiation doses. In fact, using PML with certain parameter values results in better images, acquired using 2 mGy dose, than FBP-reconstructed images acquired using 6 mGy dose.Conclusions: A range of optimal free parameters for the PML algorithm with hyperbolic and TV norm-based potentials is presented for the microcalcification detection task, in dedicated breast CT. The reported values can be used as starting values of the free parameters, when SIR techniques are used for image reconstruction. Significant improvement in image quality can be achieved by using PML with optimal combination of parameters, as compared to FBP. Importantly, these results suggest improved detection of microcalcifications can be obtained by using PML with lower radiation dose to the patient, than using FBP with higher dose.« less

High Ability and Learner Characteristics

ERIC Educational Resources Information Center

Hindal, Huda; Reid, Norman; Whitehead, Rex

2013-01-01

The outstandingly able learner has been conceptualised, in terms of test and examination performance, as the learner showing superior academic performance which is markedly better than that of peers and in ways regarded as of value by wider society. In Kuwait, such superior examination performance leads to a classification regarded as being…

40 CFR 63.176 - Quality improvement program for pumps.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., operating or maintenance practices, and pump or pump seal designs or technologies that have poorer than... shall also be used to determine if there are superior performing pump or pump seal technologies that are... average emission performance. A superior performing pump or pump seal technology is one with a leak...

40 CFR 63.176 - Quality improvement program for pumps.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., operating or maintenance practices, and pump or pump seal designs or technologies that have poorer than... shall also be used to determine if there are superior performing pump or pump seal technologies that are... average emission performance. A superior performing pump or pump seal technology is one with a leak...

40 CFR 63.1035 - Quality improvement program for pumps.

Code of Federal Regulations, 2013 CFR

2013-07-01

... determine the services, operating or maintenance practices, and pump or pump seal designs or technologies... analysis shall also be used to determine if there are superior performing pump or pump seal technologies... with poorer than average emission performance. A superior performing pump or pump seal technology is...

40 CFR 63.1035 - Quality improvement program for pumps.

Code of Federal Regulations, 2012 CFR

2012-07-01

... determine the services, operating or maintenance practices, and pump or pump seal designs or technologies... analysis shall also be used to determine if there are superior performing pump or pump seal technologies... with poorer than average emission performance. A superior performing pump or pump seal technology is...

40 CFR 63.1035 - Quality improvement program for pumps.

Code of Federal Regulations, 2011 CFR

2011-07-01

... determine the services, operating or maintenance practices, and pump or pump seal designs or technologies... analysis shall also be used to determine if there are superior performing pump or pump seal technologies... with poorer than average emission performance. A superior performing pump or pump seal technology is...

40 CFR 63.1035 - Quality improvement program for pumps.

Code of Federal Regulations, 2014 CFR

2014-07-01

... determine the services, operating or maintenance practices, and pump or pump seal designs or technologies... analysis shall also be used to determine if there are superior performing pump or pump seal technologies... with poorer than average emission performance. A superior performing pump or pump seal technology is...

40 CFR 63.176 - Quality improvement program for pumps.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., operating or maintenance practices, and pump or pump seal designs or technologies that have poorer than... shall also be used to determine if there are superior performing pump or pump seal technologies that are... average emission performance. A superior performing pump or pump seal technology is one with a leak...

Cognitive Development of Intellectually Gifted: A Piagetian Perspective.

ERIC Educational Resources Information Center

Carter, Kyle R.

1985-01-01

Relationships between intellectual giftedness and performance within Piagetian stages of 673 gifted students (10-16 years old) were investigated. Results showed that intellectually superior children out- performed children of normal ability at all age levels. Intellectually superior Ss out-performed bright-normal Ss at lower ages, but no…

Predicting outcome of status epilepticus.

PubMed

Leitinger, M; Kalss, G; Rohracher, A; Pilz, G; Novak, H; Höfler, J; Deak, I; Kuchukhidze, G; Dobesberger, J; Wakonig, A; Trinka, E

2015-08-01

Status epilepticus (SE) is a frequent neurological emergency complicated by high mortality and often poor functional outcome in survivors. The aim of this study was to review available clinical scores to predict outcome. Literature review. PubMed Search terms were "score", "outcome", and "status epilepticus" (April 9th 2015). Publications with abstracts available in English, no other language restrictions, or any restrictions concerning investigated patients were included. Two scores were identified: "Status Epilepticus Severity Score--STESS" and "Epidemiology based Mortality score in SE--EMSE". A comprehensive comparison of test parameters concerning performance, options, and limitations was performed. Epidemiology based Mortality score in SE allows detailed individualization of risk factors and is significantly superior to STESS in a retrospective explorative study. In particular, EMSE is very good at detection of good and bad outcome, whereas STESS detecting bad outcome is limited by a ceiling effect and uncertainty of correct cutoff value. Epidemiology based Mortality score in SE can be adapted to different regions in the world and to advances in medicine, as new data emerge. In addition, we designed a reporting standard for status epilepticus to enhance acquisition and communication of outcome relevant data. A data acquisition sheet used from patient admission in emergency room, from the EEG lab to intensive care unit, is provided for optimized data collection. Status Epilepticus Severity Score is easy to perform and predicts bad outcome, but has a low predictive value for good outcomes. Epidemiology based Mortality score in SE is superior to STESS in predicting good or bad outcome but needs marginally more time to perform. Epidemiology based Mortality score in SE may prove very useful for risk stratification in interventional studies and is recommended for individual outcome prediction. Prospective validation in different cohorts is needed for EMSE, whereas STESS needs further validation in cohorts with a wider range of etiologies. This article is part of a Special Issue entitled "Status Epilepticus". Copyright © 2015. Published by Elsevier Inc.

The comparison of detection methods of asymptomatic malaria in hypoendemic areas

NASA Astrophysics Data System (ADS)

Siahaan, L.; Panggabean, M.; Panggabean, Y. C.

2018-03-01

Malaria is still a problem that disrupts public health in North Sumatera. Late diagnosis will increase the chances of increased morbidity and mortality due to malaria. The early detection of asymptomatic malaria is one of the best efforts to reduce the transmission of the disease. Early detection is certainly must be done on suspect patients who have no malaria complaints. Passive Case Detection (PCD) methods seem hard to find asymptomatic malaria. This study was conducted to compare ACD (Active Case Detection) and PCD methods in asymptomatic malaria detection in the hypoendemic areas of malaria. ACD method is done by going to the sample based on secondary data. Meanwhile, PCD is done on samples that come to health services. Samples were taken randomly and diagnosis was confirmed by microscopic examination with 3% Giemsa staining, as gold standard of malaria diagnostics. There was a significant difference between ACD and PCD detection methods (p = 0.034), where ACD method was seen superior in detecting malaria patients in all categories, such as: clinical malaria (65.2%), asymptomatic malaria (65.1%) and submicroscopic malaria (58.5%). ACD detection methods are superior in detecting malaria sufferers, especially asymptomatic malaria sufferers.

Optimal MRI sequences for 68Ga-PSMA-11 PET/MRI in evaluation of biochemically recurrent prostate cancer.

PubMed

Lake, Spencer T; Greene, Kirsten L; Westphalen, Antonio C; Behr, Spencer C; Zagoria, Ronald; Small, Eric J; Carroll, Peter R; Hope, Thomas A

2017-09-19

PET/MRI can be used for the detection of disease in biochemical recurrence (BCR) patients imaged with 68 Ga-PSMA-11 PET. This study was designed to determine the optimal MRI sequences to localize positive findings on 68 Ga-PSMA-11 PET of patients with BCR after definitive therapy. Fifty-five consecutive prostate cancer patients with BCR imaged with 68 Ga-PSMA-11 3.0T PET/MRI were retrospectively analyzed. Mean PSA was 7.9 ± 12.9 ng/ml, and mean PSA doubling time was 7.1 ± 6.6 months. Detection rates of anatomic correlates for prostate-specific membrane antigen (PSMA)-positive foci were evaluated on small field of view (FOV) T2, T1 post-contrast, and diffusion-weighted images. For prostate bed recurrences, the detection rate of dynamic contrast-enhanced (DCE) imaging for PSMA-positive foci was evaluated. Finally, the detection sensitivity for PSMA-avid foci on 3- and 8-min PET acquisitions was compared. PSMA-positive foci were detected in 89.1% (49/55) of patients evaluated. Small FOV T2 performed best for lymph nodes and detected correlates for all PSMA-avid lymph nodes. DCE imaging performed the best for suspected prostate bed recurrence, detecting correlates for 87.5% (14/16) of PSMA-positive prostate bed foci. The 8-min PET acquisition performed better than the 3-min acquisition for lymph nodes smaller than 1 cm, detecting 100% (57/57) of lymph nodes less than 1 cm, compared to 78.9% (45/57) for the 3-min acquisition. PSMA PET/MRI performed well for the detection of sites of suspected recurrent disease in patients with BCR. Of the MRI sequences obtained for localization, small FOV T2 images detected the greatest proportion of PSMA-positive abdominopelvic lymph nodes and DCE imaging detected the greatest proportion of PSMA-positive prostate bed foci. The 8-min PET acquisition was superior to the 3 min acquisition for detection of small lymph nodes.

A comparison of the diagnostic accuracy of MARS MRI and ultrasound of the painful metal-on-metal hip arthroplasty.

PubMed

Siddiqui, Imran A; Sabah, Shiraz A; Satchithananda, Keshthra; Lim, Adrian K; Cro, Suzie; Henckel, Johann; Skinner, John A; Hart, Alister J

2014-08-01

Metal artifact reduction sequence (MARS) MRI and ultrasound scanning (USS) can both be used to detect pseudotumors, abductor muscle atrophy, and tendinous pathology in patients with painful metal-on-metal (MOM) hip arthroplasty. We wanted to determine the diagnostic test characteristics of USS using MARS MRI as a reference for detection of pseudotumors and muscle atrophy. PatienTS AND METHODS: We performed a prospective cohort study to compare MARS MRI and USS findings in 19 consecutive patients with unilateral MOM hips. Protocolized USS was performed by consultant musculoskeletal radiologists who were blinded regarding clinical details. Reports were independently compared with MARS MRI, the imaging gold standard, to calculate predictive values. The prevalence of pseudotumors on MARS MRI was 68% (95% CI: 43-87) and on USS it was 53% (CI: 29-76). The sensitivity of USS in detecting pseudotumors was 69% (CI 39-91) and the specificity was 83% (CI: 36-97). The sensitivity of detection of abductor muscle atrophy was 47% (CI: 24-71). In addition, joint effusion was detected in 10 cases by USS and none were seen by MARS MRI. We found a poor agreement between USS and MARS MRI. USS was inferior to MARS MRI for detection of pseudotumors and muscle atrophy, but it was superior for detection of joint effusion and tendinous pathologies. MARS MRI is more advantageous than USS for practical reasons, including preoperative planning and longitudinal comparison.

A Comparison of the Performance of Efficient Data Analysis Versus Fine Particle Dose as Metrics for the Quality Control of Aerodynamic Particle Size Distributions of Orally Inhaled Pharmaceuticals.

PubMed

Tougas, Terrence P; Goodey, Adrian P; Hardwell, Gareth; Mitchell, Jolyon; Lyapustina, Svetlana

2017-02-01

The performance of two quality control (QC) tests for aerodynamic particle size distributions (APSD) of orally inhaled drug products (OIPs) is compared. One of the tests is based on the fine particle dose (FPD) metric currently expected by the European regulators. The other test, called efficient data analysis (EDA), uses the ratio of large particle mass to small particle mass (LPM/SPM), along with impactor sized mass (ISM), to detect changes in APSD for QC purposes. The comparison is based on analysis of APSD data from four products (two different pressurized metered dose inhalers (MDIs) and two dry powder inhalers (DPIs)). It is demonstrated that in each case, EDA is able to detect shifts and abnormalities that FPD misses. The lack of sensitivity on the part of FPD is due to its "aggregate" nature, since FPD is a univariate measure of all particles less than about 5 μm aerodynamic diameter, and shifts or changes within the range encompassed by this metric may go undetected. EDA is thus shown to be superior to FPD for routine control of OIP quality. This finding augments previously reported superiority of EDA compared with impactor stage groupings (favored by US regulators) for incorrect rejections (type I errors) when incorrect acceptances (type II errors) were adjusted to the same probability for both approaches. EDA is therefore proposed as a method of choice for routine quality control of OIPs in both European and US regulatory environments.

Anatomic ligament consolidation of the superior acromioclavicular ligament and the coracoclavicular ligament complex after acute arthroscopically assisted double coracoclavicular bundle stabilization.

PubMed

Jobmann, S; Buckup, J; Colcuc, C; Roessler, P P; Zimmermann, E; Schüttler, K F; Hoffmann, R; Welsch, F; Stein, T

2017-09-18

The consolidation of the acromioclavicular (AC) and coracoclavicular (CC) ligament complex after arthroscopically assisted stabilization of acute acromioclavicular joint (ACJ) separation is still under consideration. Fifty-five consecutive patients after arthroscopically assisted double-CC-bundle stabilization within 14 days after acute high-grade ACJ separation were studied prospectively. All patients were clinically analysed preoperatively (FU0) and post-operatively (FU1 = 6 months; FU2 = 12 months). The structural MRI assessments were performed at FU0 (injured ACJ) and at FU2 bilateral (radiologic control group) and assessed separately the ligament thickness and length at defined regions for the conoid, trapezoid and the superior AC ligament. Thirty-seven patients were assessed after 6.5 months and after 16.0 months. The 16-month MRI analysis revealed for all patients continuous ligament healing for the CC-complex and the superior AC ligament with in the average hypertrophic consolidation compared to the control side. Separate conoid and trapezoid strands (double-strand configuration) were detected in 27 of 37 (73%) patients, and a single-strand configuration was detected in 10 of 37 (27%) patients; both configurations showed similar CCD data. The ligament healing was not influenced by the point of surgery, age at surgery and heterotopic ossification. The clinical outcome was increased (FU0-FU2): Rowe, 47.7-97.0 pts.; TAFT, 3.9-10.6 pts.; NAS pain , 8.9-1.4 pts. (all P < 0.05). The arthroscopically assisted double-CC-bundle stabilization within 14 days after acute high-grade ACJ separation showed 16 months after surgery sufficient consolidations of the AC and double-CC ligament complex in 73%. III, Case series.

Evaluation of image features and classification methods for Barrett's cancer detection using VLE imaging

NASA Astrophysics Data System (ADS)

Klomp, Sander; van der Sommen, Fons; Swager, Anne-Fré; Zinger, Svitlana; Schoon, Erik J.; Curvers, Wouter L.; Bergman, Jacques J.; de With, Peter H. N.

2017-03-01

Volumetric Laser Endomicroscopy (VLE) is a promising technique for the detection of early neoplasia in Barrett's Esophagus (BE). VLE generates hundreds of high resolution, grayscale, cross-sectional images of the esophagus. However, at present, classifying these images is a time consuming and cumbersome effort performed by an expert using a clinical prediction model. This paper explores the feasibility of using computer vision techniques to accurately predict the presence of dysplastic tissue in VLE BE images. Our contribution is threefold. First, a benchmarking is performed for widely applied machine learning techniques and feature extraction methods. Second, three new features based on the clinical detection model are proposed, having superior classification accuracy and speed, compared to earlier work. Third, we evaluate automated parameter tuning by applying simple grid search and feature selection methods. The results are evaluated on a clinically validated dataset of 30 dysplastic and 30 non-dysplastic VLE images. Optimal classification accuracy is obtained by applying a support vector machine and using our modified Haralick features and optimal image cropping, obtaining an area under the receiver operating characteristic of 0.95 compared to the clinical prediction model at 0.81. Optimal execution time is achieved using a proposed mean and median feature, which is extracted at least factor 2.5 faster than alternative features with comparable performance.

Detection of Viral Hemorrhagic Septicemia Virus by Quantitative Reverse Transcription Polymerase Chain Reaction from Two Fish Species at Two Sites in Lake Superior

USGS Publications Warehouse

Cornwell, Emily R.; Eckerlin, Geofrey E.; Getchell, Rodman G.; Groocock, Geoffrey H.; Thompson, Tarin M.; Batts, William N.; Casey, Rufina N.; Kurath, Gael; Winton, James R.; Bowser, Paul R.; Bain, Mark B.; Casey, James W.

2011-01-01

Viral hemorrhagic septicemia virus (VHSV) was first detected in the Laurentian Great Lakes in 2005 during a mortality event in the Bay of Quinte, Lake Ontario. Subsequent analysis of archived samples determined that the first known isolation of VHSV in the Laurentian Great Lakes was from a muskellunge Esox masquinongy collected in Lake St. Clair in 2003. By the end of 2008, mortality events and viral isolations had occurred in all of the Laurentian Great Lakes except Lake Superior. In 2009, a focused disease surveillance program was designed to determine whether VHSV was also present in Lake Superior. In this survey, 874 fish from 7 sites along the U.S. shoreline of Lake Superior were collected during June 2009. Collections were focused on nearshore species known to be susceptible to VHSV. All fish were dissected individually by using aseptic techniques and were tested for the presence of VHSV genetic material by use of a quantitative reverse transcription (qRT) polymerase chain reaction (PCR) targeting the viral nucleoprotein gene. Seventeen fish from two host species at two different sites tested positive at low levels for VHSV. All attempts to isolate virus in cell culture were unsuccessful. However, the presence of viral RNA was confirmed independently in five fish by using a nested PCR that targeted the glycoprotein (G) gene. Partial G gene sequences obtained from three fish were identical to the corresponding sequence from the original 2003 VHSV isolate (MI03) from muskellunge. These detections represent the earliest evidence for the presence of VHSV in Lake Superior and illustrate the utility of the highly sensitive qRT-PCR assay for disease surveillance in aquatic animals.

Comparison of Non-Culture-Based Methods for Detection of Systemic Fungal Infections, with an Emphasis on Invasive Candida Infections

PubMed Central

White, P. Lewis; Archer, Alice E.; Barnes, Rosemary A.

2005-01-01

The accepted limitations associated with classic culture techniques for the diagnosis of invasive fungal infections have lead to the emergence of many non-culture-based methods. With superior sensitivities and quicker turnaround times, non-culture-based methods may aid the diagnosis of invasive fungal infections. In this review of the diagnostic service, we assessed the performances of two antigen detection techniques (enzyme-linked immunosorbent assay [ELISA] and latex agglutination) with a molecular method for the detection of invasive Candida infection and invasive aspergillosis. The specificities for all three assays were high (≥97%), although the Candida PCR method had enhanced sensitivity over both ELISA and latex agglutination with values of 95%, 75%, and 25%, respectively. However, calculating significant sensitivity values for the Aspergillus detection methods was not feasible due to a low number of proven/probable cases. Despite enhanced sensitivity, the PCR method failed to detect nucleic acid in a probable case of invasive Candida infection that was detected by ELISA. In conclusion, both PCR and ELISA techniques should be used in unison to aid the detection of invasive fungal infections. PMID:15872239

Precise fiber length measurement using harmonic detection of phase-locked cavity modes

NASA Astrophysics Data System (ADS)

Terra, Osama

2018-06-01

In this paper, precise length measurements of optical fibers are performed by employing harmonic detection of the pulse-train frequency of a passively mode-locked fiber laser. This frequency is proportional to the length of the laser cavity in which the measured fiber is installed. Our proposed technique enables length measurement of long fibers from 1 to 40 km with precision from 0.4 to 8 mm and short fibers of few meters with precision as low as 26 μm. Such superior precision is achieved not only by the selection of higher harmonics of up to 1410, but also by the careful control of the wavelength at which the passive mode-locking occur, because of the broadband nature of the used gain medium.

Benzophenone based fluorophore for selective detection of Sn2+ ion: Experimental and theoretical study.

PubMed

Jadhav, Amol G; Shinde, Suvidha S; Lanke, Sandip K; Sekar, Nagaiyan

2017-03-05

Synthesis of novel benzophenone-based chemosensor is presented for the selective sensing of Sn 2+ ion. Screening of competitive metal ions was performed by competitive experiments. The specific cation recognition ability of chemosensor towards Sn 2+ was investigated by experimental (UV-visible, fluorescence spectroscopy, 1 H NMR, 13 C NMR, FTIR and HRMS) methods and further supported by Density Functional Theory study. The stoichiometric binding ratio and binding constant (K a ) for complex is found to be 1:1 and 1.50×10 4 , respectively. The detection limit of Sn 2+ towards chemosensor was found to be 0.3898ppb. Specific selectivity and superiority of chemosensor over another recently reported chemosensor is presented. Copyright © 2016 Elsevier B.V. All rights reserved.

A highly selective and simple fluorescent sensor for mercury (II) ion detection based on cysteamine-capped CdTe quantum dots synthesized by the reflux method.

PubMed

Ding, Xiaojie; Qu, Lingbo; Yang, Ran; Zhou, Yuchen; Li, Jianjun

2015-06-01

Cysteamine (CA)-capped CdTe quantum dots (QDs) (CA-CdTe QDs) were prepared by the reflux method and utilized as an efficient nano-sized fluorescent sensor to detect mercury (II) ions (Hg(2+) ). Under optimum conditions, the fluorescence quenching effect of CA-CdTe QDs was linear at Hg(2+) concentrations in the range of 6.0-450 nmol/L. The detection limit was calculated to be 4.0 nmol/L according to the 3σ IUPAC criteria. The influence of 10-fold Pb(2+) , Cu(2+) and Ag(+) on the determination of Hg(2+) was < 7% (superior to other reports based on crude QDs). Furthermore, the detection sensitivity and selectivity were much improved relative to a sensor based on the CA-CdTe QDs probe, which was prepared using a one-pot synthetic method. This CA-CdTe QDs sensor system represents a new feasibility to improve the detection performance of a QDs sensor by changing the synthesis method. Copyright © 2014 John Wiley & Sons, Ltd.

A novel rail defect detection method based on undecimated lifting wavelet packet transform and Shannon entropy-improved adaptive line enhancer

NASA Astrophysics Data System (ADS)

Hao, Qiushi; Zhang, Xin; Wang, Yan; Shen, Yi; Makis, Viliam

2018-07-01

Acoustic emission (AE) technology is sensitive to subliminal rail defects, however strong wheel-rail contact rolling noise under high-speed condition has gravely impeded detecting of rail defects using traditional denoising methods. In this context, the paper develops an adaptive detection method for rail cracks, which combines multiresolution analysis with an improved adaptive line enhancer (ALE). To obtain elaborate multiresolution information of transient crack signals with low computational cost, lifting scheme-based undecimated wavelet packet transform is adopted. In order to feature the impulsive property of crack signals, a Shannon entropy-improved ALE is proposed as a signal enhancing approach, where Shannon entropy is introduced to improve the cost function. Then a rail defect detection plan based on the proposed method for high-speed condition is put forward. From theoretical analysis and experimental verification, it is demonstrated that the proposed method has superior performance in enhancing the rail defect AE signal and reducing the strong background noise, offering an effective multiresolution approach for rail defect detection under high-speed and strong-noise condition.

Chemical Analysis of the Chinese Liquor Luzhoulaojiao by Comprehensive Two-Dimensional Gas Chromatography/Time-of-Flight Mass Spectrometry

PubMed Central

Yao, Feng; Yi, Bin; Shen, Caihong; Tao, Fei; Liu, Yumin; Lin, Zhixin; Xu, Ping

2015-01-01

Luzhoulaojiao liquor is a type of Chinese liquor that dates back hundreds of years, but whose precise chemical composition remains unknown. This paper describes the screening of the liquor and the identification of its compounds using comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GC × GC/TOF-MS). Samples were prepared by both liquid-liquid extraction and solid-phase microextraction, which facilitated the detection of thousands of compounds in the liquor, thus demonstrating the superior performance of the proposed method over those reported in previous studies. A total of 320 compounds were common to all 18 types of Luzhoulaojiao liquor studied here, and 13 abundant and potentially bioactive compounds were further quantified. The results indicated that the high-performance method presented here is well suited for the detection and identification of compounds in liquors. This study also contributes to enriching our knowledge of the contents of Chinese liquors. PMID:25857434

GDPC: Gravitation-based Density Peaks Clustering algorithm

NASA Astrophysics Data System (ADS)

Jiang, Jianhua; Hao, Dehao; Chen, Yujun; Parmar, Milan; Li, Keqin

2018-07-01

The Density Peaks Clustering algorithm, which we refer to as DPC, is a novel and efficient density-based clustering approach, and it is published in Science in 2014. The DPC has advantages of discovering clusters with varying sizes and varying densities, but has some limitations of detecting the number of clusters and identifying anomalies. We develop an enhanced algorithm with an alternative decision graph based on gravitation theory and nearby distance to identify centroids and anomalies accurately. We apply our method to some UCI and synthetic data sets. We report comparative clustering performances using F-Measure and 2-dimensional vision. We also compare our method to other clustering algorithms, such as K-Means, Affinity Propagation (AP) and DPC. We present F-Measure scores and clustering accuracies of our GDPC algorithm compared to K-Means, AP and DPC on different data sets. We show that the GDPC has the superior performance in its capability of: (1) detecting the number of clusters obviously; (2) aggregating clusters with varying sizes, varying densities efficiently; (3) identifying anomalies accurately.

Adaptive mechanism-based congestion control for networked systems

NASA Astrophysics Data System (ADS)

Liu, Zhi; Zhang, Yun; Chen, C. L. Philip

2013-03-01

In order to assure the communication quality in network systems with heavy traffic and limited bandwidth, a new ATRED (adaptive thresholds random early detection) congestion control algorithm is proposed for the congestion avoidance and resource management of network systems. Different to the traditional AQM (active queue management) algorithms, the control parameters of ATRED are not configured statically, but dynamically adjusted by the adaptive mechanism. By integrating with the adaptive strategy, ATRED alleviates the tuning difficulty of RED (random early detection) and shows a better control on the queue management, and achieve a more robust performance than RED under varying network conditions. Furthermore, a dynamic transmission control protocol-AQM control system using ATRED controller is introduced for the systematic analysis. It is proved that the stability of the network system can be guaranteed when the adaptive mechanism is finely designed. Simulation studies show the proposed ATRED algorithm achieves a good performance in varying network environments, which is superior to the RED and Gentle-RED algorithm, and providing more reliable service under varying network conditions.

Fuzzy regression modeling for tool performance prediction and degradation detection.

PubMed

Li, X; Er, M J; Lim, B S; Zhou, J H; Gan, O P; Rutkowski, L

2010-10-01

In this paper, the viability of using Fuzzy-Rule-Based Regression Modeling (FRM) algorithm for tool performance and degradation detection is investigated. The FRM is developed based on a multi-layered fuzzy-rule-based hybrid system with Multiple Regression Models (MRM) embedded into a fuzzy logic inference engine that employs Self Organizing Maps (SOM) for clustering. The FRM converts a complex nonlinear problem to a simplified linear format in order to further increase the accuracy in prediction and rate of convergence. The efficacy of the proposed FRM is tested through a case study - namely to predict the remaining useful life of a ball nose milling cutter during a dry machining process of hardened tool steel with a hardness of 52-54 HRc. A comparative study is further made between four predictive models using the same set of experimental data. It is shown that the FRM is superior as compared with conventional MRM, Back Propagation Neural Networks (BPNN) and Radial Basis Function Networks (RBFN) in terms of prediction accuracy and learning speed.

Flexible hemispheric microarrays of highly pressure-sensitive sensors based on breath figure method.

PubMed

Wang, Zhihui; Zhang, Ling; Liu, Jin; Jiang, Hao; Li, Chunzhong

2018-05-30

Recently, flexible pressure sensors featuring high sensitivity, broad sensing range and real-time detection have aroused great attention owing to their crucial role in the development of artificial intelligent devices and healthcare systems. Herein, highly sensitive pressure sensors based on hemisphere-microarray flexible substrates are fabricated via inversely templating honeycomb structures deriving from a facile and static breath figure process. The interlocked and subtle microstructures greatly improve the sensing characteristics and compressibility of the as-prepared pressure sensor, endowing it a sensitivity as high as 196 kPa-1 and a wide pressure sensing range (0-100 kPa), as well as other superior performance, including a lower detection limit of 0.5 Pa, fast response time (<26 ms) and high reversibility (>10 000 cycles). Based on the outstanding sensing performance, the potential capability of our pressure sensor in capturing physiological information and recognizing speech signals has been demonstrated, indicating promising application in wearable and intelligent electronics.

An enhanced narrow-band imaging method for the microvessel detection

NASA Astrophysics Data System (ADS)

Yu, Feng; Song, Enmin; Liu, Hong; Wan, Youming; Zhu, Jun; Hung, Chih-Cheng

2018-02-01

A medical endoscope system combined with the narrow-band imaging (NBI), has been shown to be a superior diagnostic tool for early cancer detection. The NBI can reveal the morphologic changes of microvessels in the superficial cancer. In order to improve the conspicuousness of microvessel texture, we propose an enhanced NBI method to improve the conspicuousness of endoscopic images. To obtain the more conspicuous narrow-band images, we use the edge operator to extract the edge information of the narrow-band blue and green images, and give a weight to the extracted edges. Then, the weighted edges are fused with the narrow-band blue and green images. Finally, the displayed endoscopic images are reconstructed with the enhanced narrow-band images. In addition, we evaluate the performance of enhanced narrow-band images with different edge operators. Experimental results indicate that the Sobel and Canny operators achieve the best performance of all. Compared with traditional NBI method of Olympus company, our proposed method has more conspicuous texture of microvessel.

Chemical Analysis of the Chinese Liquor Luzhoulaojiao by Comprehensive Two-Dimensional Gas Chromatography/Time-of-Flight Mass Spectrometry

NASA Astrophysics Data System (ADS)

Yao, Feng; Yi, Bin; Shen, Caihong; Tao, Fei; Liu, Yumin; Lin, Zhixin; Xu, Ping

2015-04-01

Luzhoulaojiao liquor is a type of Chinese liquor that dates back hundreds of years, but whose precise chemical composition remains unknown. This paper describes the screening of the liquor and the identification of its compounds using comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GC × GC/TOF-MS). Samples were prepared by both liquid-liquid extraction and solid-phase microextraction, which facilitated the detection of thousands of compounds in the liquor, thus demonstrating the superior performance of the proposed method over those reported in previous studies. A total of 320 compounds were common to all 18 types of Luzhoulaojiao liquor studied here, and 13 abundant and potentially bioactive compounds were further quantified. The results indicated that the high-performance method presented here is well suited for the detection and identification of compounds in liquors. This study also contributes to enriching our knowledge of the contents of Chinese liquors.

Detecting and visualizing weak signatures in hyperspectral data

NASA Astrophysics Data System (ADS)

MacPherson, Duncan James

This thesis evaluates existing techniques for detecting weak spectral signatures from remotely sensed hyperspectral data. Algorithms are presented that successfully detect hard-to-find 'mystery' signatures in unknown cluttered backgrounds. The term 'mystery' is used to describe a scenario where the spectral target and background endmembers are unknown. Sub-Pixel analysis and background suppression are used to find deeply embedded signatures which can be less than 10% of the total signal strength. Existing 'mystery target' detection algorithms are derived and compared. Several techniques are shown to be superior both visually and quantitatively. Detection performance is evaluated using confidence metrics that are developed. A multiple algorithm approach is shown to improve detection confidence significantly. Although the research focuses on remote sensing applications, the algorithms presented can be applied to a wide variety of diverse fields such as medicine, law enforcement, manufacturing, earth science, food production, and astrophysics. The algorithms are shown to be general and can be applied to both the reflective and emissive parts of the electromagnetic spectrum. The application scope is a broad one and the final results open new opportunities for many specific applications including: land mine detection, pollution and hazardous waste detection, crop abundance calculations, volcanic activity monitoring, detecting diseases in food, automobile or airplane target recognition, cancer detection, mining operations, extracting galactic gas emissions, etc.

Status of Non-indigenous Benthic Invertebrates in the Duluth-Superior Harbor and the Role of Sampling Methods in their Detection

EPA Science Inventory

As part of a study to develop recommendations for non-indigenous species (NIS) monitoring in Great Lakes areas of risk, we conducted intensive sampling in the Duluth-Superior Harbor and lower St. Louis River in 2005 and 2006. Of the >200 invertebrate taxa recorded, 19 were non-...

Detection of the posterior superior alveolar artery in the lateral sinus wall using computed tomography/cone beam computed tomography: a prevalence meta-analysis study and systematic review.

PubMed

Varela-Centelles, P; Loira-Gago, M; Seoane-Romero, J M; Takkouche, B; Monteiro, L; Seoane, J

2015-11-01

A systematic search of MEDLINE, Embase, and Proceedings Web of Science was undertaken to assess the prevalence of the posterior superior alveolar artery (PSAA) in the lateral sinus wall in sinus lift patients, as identified using computed tomography (CT)/cone beam computed tomography (CBCT). For inclusion, the article had to report PSAA detection in the bony wall using CT and/or CBCT in patients with subsinus edentulism. Studies on post-mortem findings, mixed samples (living and cadaveric), those presenting pooled results only, or studies performed for a sinus pathology were excluded. Heterogeneity was checked using an adapted version of the DerSimonian and Laird Q test, and quantified by calculating the proportion of the total variance due to between-study variance (Ri statistic). Eight hundred and eleven single papers were reviewed and filtered according to the inclusion/exclusion criteria. Ten studies were selected (1647 patients and 2740 maxillary sinuses (study unit)). The pooled prevalence of PSAA was 62.02 (95% confidence interval (CI) 46.33-77.71). CBCT studies detected PSAA more frequently (78.12, 95% CI 61.25-94.98) than CT studies (51.19, 95% CI 42.33-60.05). Conventional CT revealed thicker arteries than CBCT. It is concluded that PSAA detection is more frequent when CBCT explorations are used. Additional comparative studies controlling for potential confounding factors are needed to ascertain the actual diagnostic value of radiographic explorations for assessing the PSAA prior to sinus floor elevation procedures. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Is performance related to marketing research in the health care industry?

PubMed

Naidu, G M; Kleimenhagen, A; Pillari, G D

1994-01-01

Marketing research has grown to become indispensable for superior performance in packaged goods industries. While health care institutions are spending large amounts on marketing research, few studies focus upon the relationship of marketing research to health care organizational performance. Utilizing a national sample of U.S. hospitals, this article points out that marketing research and superior performance are positively associated.

Can Blindsight Be Superior to "Sighted-Sight"?

ERIC Educational Resources Information Center

Trevethan, Ceri T.; Sahraie, Arash; Weiskrantz, Larry

2007-01-01

DB, the first blindsight case to be tested extensively (Weiskrantz, 1986) has demonstrated the ability to detect and discriminate a range of visual stimuli presented within his perimetrically blind visual field defect. In a temporal two alternative forced choice (2AFC) detection experiment we have investigated the limits of DB's detection ability…

Induced videokeratography alterations in patients with excessive meibomian secretions.

PubMed

Markomanolakis, Marinos M; Kymionis, George D; Aslanides, Ioannis M; Astyrakakis, Nikolaos; Pallikaris, Ioannis G

2005-01-01

To describe lipid-induced specific videokeratographic (VKG) corneal changes and subsequent resolution after eyelid washing. VKG was performed with C-Scan corneal topography. In all patients an excessive meibomian gland lipid secretion was found with or without coexistent chronic posterior blepharitis. After the initial VKG, a meticulous cleaning of the lids with a mild alkali shampoo (10% Johnson's baby shampoo in sterile water) was done, first by gently scrubbing the closed eyelid fissure with the solution to mobilize and emulsify any Meibomian gland secretions followed by cleaning of the upper and lower margins individually, using Q-tip applicators soaked in the detergent. Three patients with tear film lipid layer excess (TFLE), which correlated with the presence of a superior or central corneal steepening in VKG, were studied. In two of the subjects, careful lid washing reversed either completely or partially this VKG effect, whereas in the last patient the VKG changes after artificially increasing the tear film lipid content is described. Meibomian gland lipid secretions may induce mainly superior and occasionally central VKG corneal steepening that is not correlated with any slit-lamp pathologic findings. Computerized corneal topography can help detect such corneal abnormalities, and their reversibility may distinguish them from other pathologic conditions (such as contact lens-induced warpage, eccentric ablations, irregular astigmatism, superior keratoconus).

Giftedness and Evidence for Reproducibly Superior Performance: An Account Based on the Expert Performance Framework

ERIC Educational Resources Information Center

Ericsson, K. Anders; Roring, Roy W.; Nandagopal, Kiruthiga

2007-01-01

Giftedness researchers have long debated whether there is empirical evidence to support a distinction between giftedness and attained level of achievement. In this paper we propose a general theoretical framework that establishes scientific criteria for acceptable evidence of superior reproducible performance, which any theory of exceptional…

Non-contrast CT at comparable dose to an abdominal radiograph in patients with acute renal colic; impact of iterative reconstruction on image quality and diagnostic performance.

PubMed

McLaughlin, P D; Murphy, K P; Hayes, S A; Carey, K; Sammon, J; Crush, L; O'Neill, F; Normoyle, B; McGarrigle, A M; Barry, J E; Maher, M M

2014-04-01

The aim was to assess the performance of low-dose non-contrast CT of the urinary tract (LD-CT) acquired at radiation exposures close to that of abdominal radiography using adaptive statistical iterative reconstruction (ASiR). Thirty-three patients with clinically suspected renal colic were prospectively included. Conventional dose (CD-CT) and LD-CT data sets were contemporaneously acquired. LD-CT images were reconstructed with 40 %, 70 % and 90 % ASiR. Image quality was subjectively and objectively measured. Images were also clinically interpreted. Mean ED was 0.48 ± 0.07 mSv for LD-CT compared with 4.43 ± 3.14 mSv for CD-CT. Increasing the percentage ASiR resulted in a step-wise reduction in mean objective noise (p < 0.001 for all comparisons). Seventy % ASiR LD-CT images had higher diagnostic acceptability and spatial resolution than 90 % ASiR LD-CT images (p < 0.001). Twenty-seven calculi (diameter = 5.5 ± 1.7 mm), including all ureteric stones, were correctly identified using 70 % ASiR LD-CT with two false positives and 16 false negatives (diameter = 2.3 ± 0.7 mm) equating to a sensitivity and specificity of 72 % and 94 %. Seventy % ASiR LD-CT had a sensitivity and specificity of 87 % and 100 % for detection of calculi >3 mm. Reconstruction of LD-CT images with 70 % ASiR resulted in superior image quality than FBP, 40 % ASIR and 90 % ASIR. LD-CT with ASIR demonstrates high sensitivity and specificity for detection of calculi >3 mm. • Low-dose CT studies for urinary calculus detection were performed with a mean dose of 0.48 ± 0.07 mSv • Low-dose CT with 70 % ASiR detected calculi >3 mm with a sensitivity and specificity of 87 % and 100 % • Reconstruction with 70 % ASiR was superior to filtered back projection, 40 % ASiR and 90 % ASiR images.

Low haemoglobin density for detecting iron deficiency across a large population, including pregnancy.

PubMed

Crispin, P; Sinclair, F; Andriolo, K

2016-08-01

Low haemoglobin density (LHD%) from Coulter counters has been suggested as a means to detect iron deficiency. Its performance in a broad population group, including pregnancy, has not been evaluated. A retrospective study of adult and paediatric (under 12 years old) patient samples referred for blood counts and iron studies between October 2013 and March 2015. Receiver operator characteristic (ROC) curves were constructed to evaluate the performance of LHD% adults, children, and in the antenatal subgroup. Using a strict definition for iron deficiency, compared with a selected normal cohort, LHD% had a ROC area under the curve (AUC) of 0.90 (0.89-0.91), but in an unselected cohort, the AUC fell to 0.74 (0.73-0.75) with a sensitivity of 74% and specificity of 60% at a cut-off value of 5.9%. In the paediatric cohort, the AUC was 0.79(0.73-0.85), giving a sensitivity and specificity of 75% and 68%, respectively. LHD% did not effectively identify iron deficiency in pregnancy with an AUC of 0.60 (0.54-0.65) and was no better than MCV at detecting iron deficiency. LHD% detects iron deficiency in adult and paediatric populations, but not in the antenatal setting, and does not appear superior to MCV. © 2016 John Wiley & Sons Ltd.

A new hierarchical method for inter-patient heartbeat classification using random projections and RR intervals

PubMed Central

2014-01-01

Background The inter-patient classification schema and the Association for the Advancement of Medical Instrumentation (AAMI) standards are important to the construction and evaluation of automated heartbeat classification systems. The majority of previously proposed methods that take the above two aspects into consideration use the same features and classification method to classify different classes of heartbeats. The performance of the classification system is often unsatisfactory with respect to the ventricular ectopic beat (VEB) and supraventricular ectopic beat (SVEB). Methods Based on the different characteristics of VEB and SVEB, a novel hierarchical heartbeat classification system was constructed. This was done in order to improve the classification performance of these two classes of heartbeats by using different features and classification methods. First, random projection and support vector machine (SVM) ensemble were used to detect VEB. Then, the ratio of the RR interval was compared to a predetermined threshold to detect SVEB. The optimal parameters for the classification models were selected on the training set and used in the independent testing set to assess the final performance of the classification system. Meanwhile, the effect of different lead configurations on the classification results was evaluated. Results Results showed that the performance of this classification system was notably superior to that of other methods. The VEB detection sensitivity was 93.9% with a positive predictive value of 90.9%, and the SVEB detection sensitivity was 91.1% with a positive predictive value of 42.2%. In addition, this classification process was relatively fast. Conclusions A hierarchical heartbeat classification system was proposed based on the inter-patient data division to detect VEB and SVEB. It demonstrated better classification performance than existing methods. It can be regarded as a promising system for detecting VEB and SVEB of unknown patients in clinical practice. PMID:24981916

Fluorescence background subtraction technique for hybrid fluorescence molecular tomography/x-ray computed tomography imaging of a mouse model of early stage lung cancer.

PubMed

Ale, Angelique; Ermolayev, Vladimir; Deliolanis, Nikolaos C; Ntziachristos, Vasilis

2013-05-01

The ability to visualize early stage lung cancer is important in the study of biomarkers and targeting agents that could lead to earlier diagnosis. The recent development of hybrid free-space 360-deg fluorescence molecular tomography (FMT) and x-ray computed tomography (XCT) imaging yields a superior optical imaging modality for three-dimensional small animal fluorescence imaging over stand-alone optical systems. Imaging accuracy was improved by using XCT information in the fluorescence reconstruction method. Despite this progress, the detection sensitivity of targeted fluorescence agents remains limited by nonspecific background accumulation of the fluorochrome employed, which complicates early detection of murine cancers. Therefore we examine whether x-ray CT information and bulk fluorescence detection can be combined to increase detection sensitivity. Correspondingly, we research the performance of a data-driven fluorescence background estimator employed for subtraction of background fluorescence from acquisition data. Using mice containing known fluorochromes ex vivo, we demonstrate the reduction of background signals from reconstructed images and sensitivity improvements. Finally, by applying the method to in vivo data from K-ras transgenic mice developing lung cancer, we find small tumors at an early stage compared with reconstructions performed using raw data. We conclude with the benefits of employing fluorescence subtraction in hybrid FMT-XCT for early detection studies.

Musicians' edge: A comparison of auditory processing, cognitive abilities and statistical learning.

PubMed

Mandikal Vasuki, Pragati Rao; Sharma, Mridula; Demuth, Katherine; Arciuli, Joanne

2016-12-01

It has been hypothesized that musical expertise is associated with enhanced auditory processing and cognitive abilities. Recent research has examined the relationship between musicians' advantage and implicit statistical learning skills. In the present study, we assessed a variety of auditory processing skills, cognitive processing skills, and statistical learning (auditory and visual forms) in age-matched musicians (N = 17) and non-musicians (N = 18). Musicians had significantly better performance than non-musicians on frequency discrimination, and backward digit span. A key finding was that musicians had better auditory, but not visual, statistical learning than non-musicians. Performance on the statistical learning tasks was not correlated with performance on auditory and cognitive measures. Musicians' superior performance on auditory (but not visual) statistical learning suggests that musical expertise is associated with an enhanced ability to detect statistical regularities in auditory stimuli. Copyright © 2016 Elsevier B.V. All rights reserved.

Placental Plasmodium falciparum malaria infection: Operational accuracy of HRP2 rapid diagnostic tests in a malaria endemic setting

PubMed Central

2011-01-01

Background Malaria has a negative effect on the outcome of pregnancy. Pregnant women are at high risk of severe malaria and severe haemolytic anaemia, which contribute 60-70% of foetal and perinatal losses. Peripheral blood smear microscopy under-estimates sequestered placental infections, therefore malaria rapid diagnostic tests (RDTs) detecting histidine rich protein-2 antigen (HRP-2) in peripheral blood are a potential alternative. Methods HRP-2 RDTs accuracy in detecting malaria in pregnancy (MIP >28 weeks gestation) and placental Plasmodium falciparum malaria (after childbirth) were conducted using Giemsa microscopy and placental histopathology respectively as the reference standard. The study was conducted in Mbale Hospital, using the midwives to perform and interpret the RDT results. Discordant results samples were spot checked using PCR techniques. Results Among 433 febrile women tested, RDTs had a sensitivity of 96.8% (95% CI 92-98.8), specificity of 73.5% (95% CI 67.8-78.6), a positive predictive value (PPV) of 68.0% (95% CI 61.4-73.9), and negative predictive value (NPV) of 97.5% (95% CI 94.0-99.0) in detecting peripheral P. falciparum malaria during pregnancy. At delivery, in non-symptomatic women, RDTs had a 80.9% sensitivity (95% CI 57.4-93.7) and a 87.5% specificity (95%CI 80.9-92.1), PPV of 47.2% (95% CI 30.7-64.2) and NPV of 97.1% (95% CI 92.2-99.1) in detecting placental P. falciparum infections among 173 samples. At delivery, 41% of peripheral infections were detected by microscopy without concurrent placental infection. The combination of RDTs and microscopy improved the sensitivity to 90.5% and the specificity to 98.4% for detecting placental malaria infection (McNemar's X 2> 3.84). RDTs were not superior to microscopy in detecting placental infection (McNemar's X 2< 3.84). Presence of malaria in pregnancy and active placental malaria infection were 38% and 12% respectively. Placental infections were associated with poor pregnancy outcome [pre-term, still birth and low birth weight] (aOR = 37.9) and late pregnancy malaria infection (aOR = 20.9). Mosquito net use (aOR 2.1) and increasing parity (aOR 2.7) were associated with lower risk for malaria in pregnancy. Conclusion Use of HRP-2 RDTs to detect malaria in pregnancy in symptomatic women was accurate when performed by midwives. A combination of RDTs and microscopy provided the best means of detecting placental malaria. RDTs were not superior to microscopy in detecting placental infection. With a high sensitivity and specificity, RDTs could be a useful tool for assessing malaria in pregnancy, with further (cost-) effectiveness studies. PMID:22004666

Plasma free versus deconjugated metanephrines for diagnosis of phaeochromocytoma

PubMed Central

Pamporaki, Christina; Därr, Roland; Bursztyn, Michael; Stephan, Glöckner; Bornstein, Stefan R.; Lenders, Jacques W.M.; Pacak, Karel; Krinner, Axel; Eisenhofer, Graeme

2013-01-01

Summary Background Diagnosis of phaeochromocytoma is commonly performed by measurements of plasma free normetanephrine and metanephrine. Plasma deconjugated normetanephrine and metanephrine have been proposed as alternative equivalent, but easier to measure biomarkers. Objective The aim of this study was to compare the diagnostic performances of plasma free versus deconjugated normetanephrine and metanephrine in patients tested for phaeochromocytoma. Methods The study population included a reference group of 262 normotensive and hypertensive volunteers, 198 patients with phaeochromocytoma and 528 patients initially suspected of having the tumour, but with negative investigations after at least 2 years of follow up. Measurements were performed using liquid chromatography with electrochemical detection. Results Median plasma concentrations of free normetanephrine were 17-fold higher in patients with phaeochromocytoma than in the reference population, a 72% larger (p<0.001) difference than that for the 10-fold higher levels of plasma deconjugated normetanephrine. In contrast, relative increases of plasma concentrations of free and deconjugated metanephrine were similar. Using upper cut-offs established in the reference population, measurements of plasma free metabolites provided superior diagnostic performance than deconjugated metabolites according to measures of both sensitivity (97% vs 92%, p=0.002) and specificity (93 vs 89%, p=0.012). The area under the receiver operating characteristic curve for the free metabolites was larger than that for the deconjugated metabolites (0.986 vs 0.965, p<0.001). Conclusion Measurements of plasma free normetanephrine and metanephrine are superior to the deconjugated metabolites for diagnosis of phaeochromocytoma. PMID:23461656

Integrated species distribution models: combining presence-background data and site-occupancy data with imperfect detection

USGS Publications Warehouse

Koshkina, Vira; Wang, Yang; Gordon, Ascelin; Dorazio, Robert; White, Matthew; Stone, Lewi

2017-01-01

Two main sources of data for species distribution models (SDMs) are site-occupancy (SO) data from planned surveys, and presence-background (PB) data from opportunistic surveys and other sources. SO surveys give high quality data about presences and absences of the species in a particular area. However, due to their high cost, they often cover a smaller area relative to PB data, and are usually not representative of the geographic range of a species. In contrast, PB data is plentiful, covers a larger area, but is less reliable due to the lack of information on species absences, and is usually characterised by biased sampling. Here we present a new approach for species distribution modelling that integrates these two data types.We have used an inhomogeneous Poisson point process as the basis for constructing an integrated SDM that fits both PB and SO data simultaneously. It is the first implementation of an Integrated SO–PB Model which uses repeated survey occupancy data and also incorporates detection probability.The Integrated Model's performance was evaluated, using simulated data and compared to approaches using PB or SO data alone. It was found to be superior, improving the predictions of species spatial distributions, even when SO data is sparse and collected in a limited area. The Integrated Model was also found effective when environmental covariates were significantly correlated. Our method was demonstrated with real SO and PB data for the Yellow-bellied glider (Petaurus australis) in south-eastern Australia, with the predictive performance of the Integrated Model again found to be superior.PB models are known to produce biased estimates of species occupancy or abundance. The small sample size of SO datasets often results in poor out-of-sample predictions. Integrated models combine data from these two sources, providing superior predictions of species abundance compared to using either data source alone. Unlike conventional SDMs which have restrictive scale-dependence in their predictions, our Integrated Model is based on a point process model and has no such scale-dependency. It may be used for predictions of abundance at any spatial-scale while still maintaining the underlying relationship between abundance and area.

A simple bedside blood test (Fibrofast; FIB-5) is superior to FIB-4 index for the differentiation between non-significant and significant fibrosis in patients with chronic hepatitis C.

PubMed

Shiha, G; Seif, S; Eldesoky, A; Elbasiony, M; Soliman, R; Metwally, A; Zalata, K; Mikhail, N

2017-05-01

A simple non-invasive score (Fibrofast, FIB-5) was developed using five routine laboratory tests (ALT, AST, alkaline phosphatase, albumin and platelets count) for the detection of significant hepatic fibrosis in patients with chronic hepatitis C. The FIB-4 index is a non-invasive test for the assessment of liver fibrosis, and a score of ≤1.45 enables the correct identification of patients who have non-significant (F0-1) from significant fibrosis (F2-4), and could avoid liver biopsy. The aim of this study was to compare the performance characteristics of FIB-5 and FIB-4 to differentiate between non-significant and significant fibrosis. A cross-sectional study included 604 chronic HCV patients. All liver biopsies were scored using the METAVIR system. Both FIB-5 and FIB-4 scores were measured and the performance characteristics were calculated using the ROC curve. The performance characteristics of FIB-5 at ≥7.5 and FIB-4 at ≤1.45 for the differentiation between non-significant fibrosis and significant fibrosis were: specificity 94.4%, PPV 85.7%, and specificity 54.9%, PPV 55.7% respectively. FIB-5 score at the new cutoff is superior to FIB-4 index for the differentiation between non-significant and significant fibrosis.

An Improved Unsupervised Image Segmentation Evaluation Approach Based on - and Over-Segmentation Aware

NASA Astrophysics Data System (ADS)

Su, Tengfei

2018-04-01

In this paper, an unsupervised evaluation scheme for remote sensing image segmentation is developed. Based on a method called under- and over-segmentation aware (UOA), the new approach is improved by overcoming the defect in the part of estimating over-segmentation error. Two cases of such error-prone defect are listed, and edge strength is employed to devise a solution to this issue. Two subsets of high resolution remote sensing images were used to test the proposed algorithm, and the experimental results indicate its superior performance, which is attributed to its improved OSE detection model.

Biomedical engineering tasks. [electrode development for electrocardiography and electroencephalography

NASA Technical Reports Server (NTRS)

1972-01-01

Electrocardiographic and vectorcardiographic bioinstrumentation work centered on the development of a new electrode system harness for Project Skylab. Evaluation of several silver electrode configurations proved superior impedance voltage performance for silver/silver chloride electrodes mounted flush by using a paste adhesive. A portable ECG processor has been designed and a breadboard unit has been built to sample ECG input data at a rate of 500 samples per second for arrhythmia detection. A small real time display driver program has been developed for statistical analysis on selected QPS features. Engineering work on a sleep monitoring cap assembly continued.

Large-size porous ZnO flakes with superior gas-sensing performance

NASA Astrophysics Data System (ADS)

Wen, Wei; Wu, Jin-Ming; Wang, Yu-De

2012-06-01

A simple top-down route is developed to fabricate large size porous ZnO flakes via solution combustion synthesis followed by a subsequent calcination in air, which is template-free and can be easily enlarged to an industrial scale. The achieved porous ZnO flakes, which are tens to hundreds of micrometers in flat and tens of nanometers in thickness, exhibit high response for detecting acetone and ethanol, because the unique two-dimensional architecture shortens effectively the gas diffusion distance and provides highly accessible open channels and active surfaces for the target gas.

Visual search for emotional expressions: Effect of stimulus set on anger and happiness superiority.

PubMed

Savage, Ruth A; Becker, Stefanie I; Lipp, Ottmar V

2016-01-01

Prior reports of preferential detection of emotional expressions in visual search have yielded inconsistent results, even for face stimuli that avoid obvious expression-related perceptual confounds. The current study investigated inconsistent reports of anger and happiness superiority effects using face stimuli drawn from the same database. Experiment 1 excluded procedural differences as a potential factor, replicating a happiness superiority effect in a procedure that previously yielded an anger superiority effect. Experiments 2a and 2b confirmed that image colour or poser gender did not account for prior inconsistent findings. Experiments 3a and 3b identified stimulus set as the critical variable, revealing happiness or anger superiority effects for two partially overlapping sets of face stimuli. The current results highlight the critical role of stimulus selection for the observation of happiness or anger superiority effects in visual search even for face stimuli that avoid obvious expression related perceptual confounds and are drawn from a single database.

High spectral resolution of gamma-rays at room temperature by perovskite CsPbBr 3 single crystals

DOE PAGES

He, Yihui; Matei, Liviu; Jung, Hee Joon; ...

2018-04-23

Gamma-ray detection and spectroscopy is the quantitative determination of their energy spectra, and is of critical value and critically important in diverse technological and scientific fields. Here we report an improved melt growth method for cesium lead bromide and a special detector design with asymmetrical metal electrode configuration that leads to a high performance at room temperature. As-grown centimeter-sized crystals possess extremely low impurity levels (below 10 p.p.m. for total 69 elements) and detectors achieve 3.9% energy resolution for 122 keV 57Co gamma-ray and 3.8% for 662 keV 137Cs gamma-ray. Cesium lead bromide is unique among all gamma-ray detection materialsmore » in that its hole transport properties are responsible for the high performance. The superior mobility-lifetime product for holes (1.34 × 10 –3 cm 2 V –1) derives mainly from the record long hole carrier lifetime (over 25 μs). Here, the easily scalable crystal growth and high-energy resolution, highlight cesium lead bromide as an exceptional next generation material for room temperature radiation detection.« less

High spectral resolution of gamma-rays at room temperature by perovskite CsPbBr 3 single crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Yihui; Matei, Liviu; Jung, Hee Joon

Gamma-ray detection and spectroscopy is the quantitative determination of their energy spectra, and is of critical value and critically important in diverse technological and scientific fields. Here we report an improved melt growth method for cesium lead bromide and a special detector design with asymmetrical metal electrode configuration that leads to a high performance at room temperature. As-grown centimeter-sized crystals possess extremely low impurity levels (below 10 p.p.m. for total 69 elements) and detectors achieve 3.9% energy resolution for 122 keV 57Co gamma-ray and 3.8% for 662 keV 137Cs gamma-ray. Cesium lead bromide is unique among all gamma-ray detection materialsmore » in that its hole transport properties are responsible for the high performance. The superior mobility-lifetime product for holes (1.34 × 10 –3 cm 2 V –1) derives mainly from the record long hole carrier lifetime (over 25 μs). Here, the easily scalable crystal growth and high-energy resolution, highlight cesium lead bromide as an exceptional next generation material for room temperature radiation detection.« less

Single-Use, Electricity-Free Amplification Device for Detection of HIV-1

PubMed Central

Curtis, Kelly A.; Rudolph, Donna L.; Morrison, Daphne; Guelig, Dylan; Diesburg, Steven; McAdams, David; Burton, Robert A.; LaBarre, Paul; Owen, Michele

2016-01-01

Early and accurate diagnosis of HIV is key for the reduction of transmission and initiation of patient care. The availability of a rapid nucleic acid test (NAT) for use at the point-of-care (POC) will fill a gap in HIV diagnostics, improving the diagnosis of acute infection and HIV in infants born to infected mothers. In this study, we evaluated the performance of non-instrumented nucleic acid amplification, single-use disposable (NINA-SUD) devices for the detection of HIV-1 in whole blood using reverse-transcription, loop-mediated isothermal amplification (RT-LAMP) with lyophilized reagents. The NINA-SUD heating device harnesses the heat from an exothermic chemical reaction initiated by the addition of saline to magnesium iron powder. Reproducibility was demonstrated between NINA-SUD units and comparable, if not superior, performance for detecting clinical specimens was observed as compared to the thermal cycler. The stability of the lyophilized HIV-1 RT-LAMP reagents was also demonstrated following storage at −20, 4, 25, and 30°C for up to one month. The single-use, disposable NAT minimizes hands-on time and has the potential to facilitate HIV-1 testing in resource-limited settings or at the POC. PMID:27616198

Porous NiCo2O4 nanoarray-integrated binder-free 3D open electrode offers a highly efficient sensing platform for enzyme-free glucose detection.

PubMed

Luo, X; Huang, M; He, D; Wang, M; Zhang, Y; Jiang, P

2018-05-29

High electrical conductivity and the exposure to more active sites are crucial to boost the performance of a glucose sensor. A porous binary metal oxide nanoarray integrated on a binder-free 3D electrode is expected to offer a highly sensitive sensing platform. As a model, porous NiCo2O4 nanowire arrays supported on carbon cloth (NiCo2O4 NWA/CC) have been prepared and used for enzyme-free glucose sensing. NiCo2O4 NWA/CC shows larger effective surface area, superior electronic conductivity, and higher catalytic activity towards enzyme-free glucose sensing, with a linear range from 1 μM to 0.63 mM, a sensitivity of 4.12 mA mM-1 cm-2, and low detection limit of 0.5 μM. Moreover, NiCo2O4 NWA/CC also displays good selectivity and stability and thus, it can be reliable for glucose detection in human serum samples. These findings inspire the fabrication of a high-performance electrochemical sensing platform by preparing porous binary metal oxide nanoarrays supported on a 3D conductive substrate.

Lower Activation in Frontal Cortex and Posterior Cingulate Cortex Observed during Sex Determination Test in Early-Stage Dementia of the Alzheimer Type

PubMed Central

Rajmohan, Ravi; Anderson, Ronald C.; Fang, Dan; Meyer, Austin G.; Laengvejkal, Pavis; Julayanont, Parunyou; Hannabas, Greg; Linton, Kitten; Culberson, John; Khan, Hafiz; De Toledo, John; Reddy, P. Hemachandra; O’Boyle, Michael W.

2017-01-01

Face-labeling refers to the ability to classify faces into social categories. This plays a critical role in human interaction as it serves to define concepts of socially acceptable interpersonal behavior. The purpose of the current study was to characterize, what, if any, impairments in face-labeling are detectable in participants with early-stage clinically diagnosed dementia of the Alzheimer type (CDDAT) through the use of the sex determination test (SDT). In the current study, four (1 female, 3 males) CDDAT and nine (4 females, 5 males) age-matched neurotypicals (NT) completed the SDT using chimeric faces while undergoing BOLD fMRI. It was expected that CDDAT participants would have poor verbal fluency, which would correspond to poor performance on the SDT. This could be explained by decreased activation and connectivity patterns within the fusiform face area (FFA) and anterior cingulate cortex (ACC). DTI was also performed to test the association of pathological deterioration of connectivity in the uncinate fasciculus (UF) and verbally-mediated performance. CDDAT showed lower verbal fluency test (VFT) performance, but VFT was not significantly correlated to SDT and no significant difference was seen between CDDAT and NT for SDT performance as half of the CDDAT performed substantially worse than NT while the other half performed similarly. BOLD fMRI of SDT displayed differences in the left superior frontal gyrus and posterior cingulate cortex (PCC), but not the FFA or ACC. Furthermore, although DTI showed deterioration of the right inferior and superior longitudinal fasciculi, as well as the PCC, it did not demonstrate significant deterioration of UF tracts. Taken together, early-stage CDDAT may represent a common emerging point for the loss of face labeling ability. PMID:28588478

Lower Activation in Frontal Cortex and Posterior Cingulate Cortex Observed during Sex Determination Test in Early-Stage Dementia of the Alzheimer Type.

PubMed

Rajmohan, Ravi; Anderson, Ronald C; Fang, Dan; Meyer, Austin G; Laengvejkal, Pavis; Julayanont, Parunyou; Hannabas, Greg; Linton, Kitten; Culberson, John; Khan, Hafiz; De Toledo, John; Reddy, P Hemachandra; O'Boyle, Michael W

2017-01-01

Face-labeling refers to the ability to classify faces into social categories. This plays a critical role in human interaction as it serves to define concepts of socially acceptable interpersonal behavior. The purpose of the current study was to characterize, what, if any, impairments in face-labeling are detectable in participants with early-stage clinically diagnosed dementia of the Alzheimer type (CDDAT) through the use of the sex determination test (SDT). In the current study, four (1 female, 3 males) CDDAT and nine (4 females, 5 males) age-matched neurotypicals (NT) completed the SDT using chimeric faces while undergoing BOLD fMRI. It was expected that CDDAT participants would have poor verbal fluency, which would correspond to poor performance on the SDT. This could be explained by decreased activation and connectivity patterns within the fusiform face area (FFA) and anterior cingulate cortex (ACC). DTI was also performed to test the association of pathological deterioration of connectivity in the uncinate fasciculus (UF) and verbally-mediated performance. CDDAT showed lower verbal fluency test (VFT) performance, but VFT was not significantly correlated to SDT and no significant difference was seen between CDDAT and NT for SDT performance as half of the CDDAT performed substantially worse than NT while the other half performed similarly. BOLD fMRI of SDT displayed differences in the left superior frontal gyrus and posterior cingulate cortex (PCC), but not the FFA or ACC. Furthermore, although DTI showed deterioration of the right inferior and superior longitudinal fasciculi, as well as the PCC, it did not demonstrate significant deterioration of UF tracts. Taken together, early-stage CDDAT may represent a common emerging point for the loss of face labeling ability.

Dimensions of Manic Symptoms in Youth: Psychosocial Impairment and Cognitive Performance in the IMAGEN Sample

ERIC Educational Resources Information Center

Stringaris, Argyris; Castellanos-Ryan, Natalie; Banaschewski, Tobias; Barker, Gareth J.; Bokde, Arun L.; Bromberg, Uli; Büchel, Christian; Fauth-Bühler, Mira; Flor, Herta; Frouin, Vincent; Gallinat, Juergen; Garavan, Hugh; Gowland, Penny; Heinz, Andreas; Itterman, Bernd; Lawrence, Claire; Nees, Frauke; Paillere-Martinot, Marie-Laure; Paus, Tomas; Pausova, Zdenka; Rietschel, Marcella; Smolka, Michael N.; Schumann, Gunter; Goodman, Robert; Conrod, Patricia

2014-01-01

Background: It has been reported that mania may be associated with superior cognitive performance. In this study, we test the hypothesis that manic symptoms in youth separate along two correlated dimensions and that a symptom constellation of high energy and cheerfulness is associated with superior cognitive performance. Method: We studied 1755…

Automated Nucleic Acid Extraction Systems for Detecting Cytomegalovirus and Epstein-Barr Virus Using Real-Time PCR: A Comparison Study Between the QIAsymphony RGQ and QIAcube Systems.

PubMed

Kim, Hanah; Hur, Mina; Kim, Ji Young; Moon, Hee Won; Yun, Yeo Min; Cho, Hyun Chan

2017-03-01

Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) are increasingly important in immunocompromised patients. Nucleic acid extraction methods could affect the results of viral nucleic acid amplification tests. We compared two automated nucleic acid extraction systems for detecting CMV and EBV using real-time PCR assays. One hundred and fifty-three whole blood (WB) samples were tested for CMV detection, and 117 WB samples were tested for EBV detection. Viral nucleic acid was extracted in parallel by using QIAsymphony RGQ and QIAcube (Qiagen GmbH, Germany), and real-time PCR assays for CMV and EBV were performed with a Rotor-Gene Q real-time PCR cycler (Qiagen). Detection rates for CMV and EBV were compared, and agreements between the two systems were analyzed. The detection rate of CMV and EBV differed significantly between the QIAsymphony RGQ and QIAcube systems (CMV, 59.5% [91/153] vs 43.8% [67/153], P=0.0005; EBV, 59.0% [69/117] vs 42.7% [50/117], P=0.0008). The two systems showed moderate agreement for CMV and EBV detection (kappa=0.43 and 0.52, respectively). QIAsymphony RGQ showed a negligible correlation with QIAcube for quantitative EBV detection. QIAcube exhibited EBV PCR inhibition in 23.9% (28/117) of samples. Automated nucleic acid extraction systems have different performances and significantly affect the detection of viral pathogens. The QIAsymphony RGQ system appears to be superior to the QIAcube system for detecting CMV and EBV. A suitable sample preparation system should be considered for optimized nucleic acid amplification in clinical laboratories.

Night vision: requirements and possible roadmap for FIR and NIR systems

NASA Astrophysics Data System (ADS)

Källhammer, Jan-Erik

2006-04-01

A night vision system must increase visibility in situations where only low beam headlights can be used today. As pedestrians and animals have the highest risk increase in night time traffic due to darkness, the ability of detecting those objects should be the main performance criteria, and the system must remain effective when facing the headlights of oncoming vehicles. Far infrared system has been shown to be superior to near infrared system in terms of pedestrian detection distance. Near infrared images were rated to have significantly higher visual clutter compared with far infrared images. Visual clutter has been shown to correlate with reduction in detection distance of pedestrians. Far infrared images are perceived as being more unusual and therefore more difficult to interpret, although the image appearance is likely related to the lower visual clutter. However, the main issue comparing the two technologies should be how well they solve the driver's problem with insufficient visibility under low beam conditions, especially of pedestrians and other vulnerable road users. With the addition of an automatic detection aid, a main issue will be whether the advantage of FIR systems will vanish given NIR systems with well performing automatic pedestrian detection functionality. The first night vision introductions did not generate the sales volumes initially expected. A renewed interest in night vision systems are however to be expected after the release of night vision systems by BMW, Mercedes and Honda, the latter with automatic pedestrian detection.

Tomosynthesis for the early detection of pulmonary emphysema: diagnostic performance compared with chest radiography, using multidetector computed tomography as reference.

PubMed

Yamada, Yoshitake; Jinzaki, Masahiro; Hashimoto, Masahiro; Shiomi, Eisuke; Abe, Takayuki; Kuribayashi, Sachio; Ogawa, Kenji

2013-08-01

To compare the diagnostic performance of tomosynthesis with that of chest radiography for the detection of pulmonary emphysema, using multidetector computed tomography (MDCT) as reference. Forty-eight patients with and 63 without pulmonary emphysema underwent chest MDCT, tomosynthesis and radiography on the same day. Two blinded radiologists independently evaluated the tomosynthesis images and radiographs for the presence of pulmonary emphysema. Axial and coronal MDCT images served as the reference standard and the percentage lung volume with attenuation values of -950 HU or lower (LAA-950) was evaluated to determine the extent of emphysema. Receiver-operating characteristic (ROC) analysis and generalised estimating equations model were used. ROC analysis revealed significantly better performance (P < 0.0001) of tomosynthesis than radiography for the detection of pulmonary emphysema. The average sensitivity, specificity, positive predictive value and negative predictive value of tomosynthesis were 0.875, 0.968, 0.955 and 0.910, respectively, whereas the values for radiography were 0.479, 0.913, 0.815 and 0.697, respectively. For both tomosynthesis and radiography, the sensitivity increased with increasing LAA-950. The diagnostic performance of tomosynthesis was significantly superior to that of radiography for the detection of pulmonary emphysema. In both tomosynthesis and radiography, the sensitivity was affected by the LAA-950. • Tomosynthesis showed significantly better diagnostic performance for pulmonary emphysema than radiography. • Interobserver agreement for tomosynthesis was significantly higher than that for radiography. • Sensitivity increased with increasing LAA -950 in both tomosynthesis and radiography. • Tomosynthesis imparts a similar radiation dose to two projection chest radiography. • Radiation dose and cost of tomosynthesis are lower than those of MDCT.

Automatic identification of epileptic seizures from EEG signals using linear programming boosting.

PubMed

Hassan, Ahnaf Rashik; Subasi, Abdulhamit

2016-11-01

Computerized epileptic seizure detection is essential for expediting epilepsy diagnosis and research and for assisting medical professionals. Moreover, the implementation of an epilepsy monitoring device that has low power and is portable requires a reliable and successful seizure detection scheme. In this work, the problem of automated epilepsy seizure detection using singe-channel EEG signals has been addressed. At first, segments of EEG signals are decomposed using a newly proposed signal processing scheme, namely complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN). Six spectral moments are extracted from the CEEMDAN mode functions and train and test matrices are formed afterward. These matrices are fed into the classifier to identify epileptic seizures from EEG signal segments. In this work, we implement an ensemble learning based machine learning algorithm, namely linear programming boosting (LPBoost) to perform classification. The efficacy of spectral features in the CEEMDAN domain is validated by graphical and statistical analyses. The performance of CEEMDAN is compared to those of its predecessors to further inspect its suitability. The effectiveness and the appropriateness of LPBoost are demonstrated as opposed to the commonly used classification models. Resubstitution and 10 fold cross-validation error analyses confirm the superior algorithm performance of the proposed scheme. The algorithmic performance of our epilepsy seizure identification scheme is also evaluated against state-of-the-art works in the literature. Experimental outcomes manifest that the proposed seizure detection scheme performs better than the existing works in terms of accuracy, sensitivity, specificity, and Cohen's Kappa coefficient. It can be anticipated that owing to its use of only one channel of EEG signal, the proposed method will be suitable for device implementation, eliminate the onus of clinicians for analyzing a large bulk of data manually, and expedite epilepsy diagnosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Heart Transplant in Patient With Isolated Left Superior Vena Cava by Atrial Appendage Rotation.

PubMed

Reyes, Karl M; Gupta, Dipankar; Fricker, Frederick Jay; Cooke, Susan; Bleiweis, Mark S

2018-06-01

Orthotopic heart transplantation in patients with an isolated persistent left superior vena cava is extremely rare, and the anastomotic connection between a right-sided donor superior vena cava and left-sided recipient superior vena cava can be challenging to perform. We present a novel technique used in an infant female, using the left atrial appendage to extend the superior vena cava anastomosis. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Superior Detection of Threat-Relevant Stimuli in Infancy

ERIC Educational Resources Information Center

LoBue, Vanessa; DeLoache, Judy S.

2010-01-01

The ability to quickly detect potential threat is an important survival mechanism for humans and other animals. Past research has established that adults have an attentional bias for the detection of threat-relevant stimuli, including snakes and spiders as well as angry human faces. Recent studies have documented that preschool children also…

Detection of Apical Root Cracks Using Spectral Domain and Swept-source Optical Coherence Tomography.

PubMed

de Oliveira, Bruna Paloma; Câmara, Andréa Cruz; Duarte, Daniel Amancio; Gomes, Anderson Stevens Leonidas; Heck, Richard John; Antonino, Antonio Celso Dantas; Aguiar, Carlos Menezes

2017-07-01

This study aimed to evaluate the ability of 2 optical coherence tomographic (OCT) systems to detect apical dentinal microcracks. Twenty extracted human single-rooted mandibular incisors were selected. After root canal preparation with an R40 Reciproc file (VDW, Munich, Germany), the specimens presenting apical microcracks were identified using micro-computed tomographic (micro-CT) scanning as the gold standard. Then, the apical portions of the roots were imaged with spectral domain OCT (SD-OCT) and swept-source OCT systems, and the resulting images were blindly evaluated by 3 independent examiners to detect microcracks. The diagnostic performance of each OCT device was calculated, and statistical analysis was performed. Based on the micro-CT images, 12 (60%) roots presented dentinal microcracks in the apical region. The images generated by the OCT systems were able to show microcrack lines at the same location as the corresponding micro-CT cross sections. Although the diagnostic performance of the SD-OCT device was superior, there were no statistically significant differences between the 2 OCT devices (P > .05). Interexaminer agreement was substantial to almost perfect for the SD-OCT system and moderate to almost perfect for the swept-source OCT system, whereas intraexaminer agreement was substantial to almost perfect for both OCT devices. The detection ability verified for both OCT systems renders them promising tools for the diagnosis of apical microcracks. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Evaluation of Nine Somatic Variant Callers for Detection of Somatic Mutations in Exome and Targeted Deep Sequencing Data.

PubMed

Krøigård, Anne Bruun; Thomassen, Mads; Lænkholm, Anne-Vibeke; Kruse, Torben A; Larsen, Martin Jakob

2016-01-01

Next generation sequencing is extensively applied to catalogue somatic mutations in cancer, in research settings and increasingly in clinical settings for molecular diagnostics, guiding therapy decisions. Somatic variant callers perform paired comparisons of sequencing data from cancer tissue and matched normal tissue in order to detect somatic mutations. The advent of many new somatic variant callers creates a need for comparison and validation of the tools, as no de facto standard for detection of somatic mutations exists and only limited comparisons have been reported. We have performed a comprehensive evaluation using exome sequencing and targeted deep sequencing data of paired tumor-normal samples from five breast cancer patients to evaluate the performance of nine publicly available somatic variant callers: EBCall, Mutect, Seurat, Shimmer, Indelocator, Somatic Sniper, Strelka, VarScan 2 and Virmid for the detection of single nucleotide mutations and small deletions and insertions. We report a large variation in the number of calls from the nine somatic variant callers on the same sequencing data and highly variable agreement. Sequencing depth had markedly diverse impact on individual callers, as for some callers, increased sequencing depth highly improved sensitivity. For SNV calling, we report EBCall, Mutect, Virmid and Strelka to be the most reliable somatic variant callers for both exome sequencing and targeted deep sequencing. For indel calling, EBCall is superior due to high sensitivity and robustness to changes in sequencing depths.

Evaluation of Nine Somatic Variant Callers for Detection of Somatic Mutations in Exome and Targeted Deep Sequencing Data

PubMed Central

Krøigård, Anne Bruun; Thomassen, Mads; Lænkholm, Anne-Vibeke; Kruse, Torben A.; Larsen, Martin Jakob

2016-01-01

Next generation sequencing is extensively applied to catalogue somatic mutations in cancer, in research settings and increasingly in clinical settings for molecular diagnostics, guiding therapy decisions. Somatic variant callers perform paired comparisons of sequencing data from cancer tissue and matched normal tissue in order to detect somatic mutations. The advent of many new somatic variant callers creates a need for comparison and validation of the tools, as no de facto standard for detection of somatic mutations exists and only limited comparisons have been reported. We have performed a comprehensive evaluation using exome sequencing and targeted deep sequencing data of paired tumor-normal samples from five breast cancer patients to evaluate the performance of nine publicly available somatic variant callers: EBCall, Mutect, Seurat, Shimmer, Indelocator, Somatic Sniper, Strelka, VarScan 2 and Virmid for the detection of single nucleotide mutations and small deletions and insertions. We report a large variation in the number of calls from the nine somatic variant callers on the same sequencing data and highly variable agreement. Sequencing depth had markedly diverse impact on individual callers, as for some callers, increased sequencing depth highly improved sensitivity. For SNV calling, we report EBCall, Mutect, Virmid and Strelka to be the most reliable somatic variant callers for both exome sequencing and targeted deep sequencing. For indel calling, EBCall is superior due to high sensitivity and robustness to changes in sequencing depths. PMID:27002637

46 CFR 401.410 - Basic rates and charges on Lakes Huron, Michigan and Superior and the St. Mary's River.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Superior and the St. Mary's River. 401.410 Section 401.410 Shipping COAST GUARD (GREAT LAKES PILOTAGE... Services § 401.410 Basic rates and charges on Lakes Huron, Michigan and Superior and the St. Mary's River... performed by U.S. registered pilots on Lakes Huron, Michigan, and Superior and the St. Mary's River. (a...

An improved method to detect correct protein folds using partial clustering.

PubMed

Zhou, Jianjun; Wishart, David S

2013-01-16

Structure-based clustering is commonly used to identify correct protein folds among candidate folds (also called decoys) generated by protein structure prediction programs. However, traditional clustering methods exhibit a poor runtime performance on large decoy sets. We hypothesized that a more efficient "partial" clustering approach in combination with an improved scoring scheme could significantly improve both the speed and performance of existing candidate selection methods. We propose a new scheme that performs rapid but incomplete clustering on protein decoys. Our method detects structurally similar decoys (measured using either C(α) RMSD or GDT-TS score) and extracts representatives from them without assigning every decoy to a cluster. We integrated our new clustering strategy with several different scoring functions to assess both the performance and speed in identifying correct or near-correct folds. Experimental results on 35 Rosetta decoy sets and 40 I-TASSER decoy sets show that our method can improve the correct fold detection rate as assessed by two different quality criteria. This improvement is significantly better than two recently published clustering methods, Durandal and Calibur-lite. Speed and efficiency testing shows that our method can handle much larger decoy sets and is up to 22 times faster than Durandal and Calibur-lite. The new method, named HS-Forest, avoids the computationally expensive task of clustering every decoy, yet still allows superior correct-fold selection. Its improved speed, efficiency and decoy-selection performance should enable structure prediction researchers to work with larger decoy sets and significantly improve their ab initio structure prediction performance.

An improved method to detect correct protein folds using partial clustering

PubMed Central

2013-01-01

Background Structure-based clustering is commonly used to identify correct protein folds among candidate folds (also called decoys) generated by protein structure prediction programs. However, traditional clustering methods exhibit a poor runtime performance on large decoy sets. We hypothesized that a more efficient “partial“ clustering approach in combination with an improved scoring scheme could significantly improve both the speed and performance of existing candidate selection methods. Results We propose a new scheme that performs rapid but incomplete clustering on protein decoys. Our method detects structurally similar decoys (measured using either Cα RMSD or GDT-TS score) and extracts representatives from them without assigning every decoy to a cluster. We integrated our new clustering strategy with several different scoring functions to assess both the performance and speed in identifying correct or near-correct folds. Experimental results on 35 Rosetta decoy sets and 40 I-TASSER decoy sets show that our method can improve the correct fold detection rate as assessed by two different quality criteria. This improvement is significantly better than two recently published clustering methods, Durandal and Calibur-lite. Speed and efficiency testing shows that our method can handle much larger decoy sets and is up to 22 times faster than Durandal and Calibur-lite. Conclusions The new method, named HS-Forest, avoids the computationally expensive task of clustering every decoy, yet still allows superior correct-fold selection. Its improved speed, efficiency and decoy-selection performance should enable structure prediction researchers to work with larger decoy sets and significantly improve their ab initio structure prediction performance. PMID:23323835

What Neural Substrates Trigger the Adept Scientific Pattern Discovery by Biologists?

NASA Astrophysics Data System (ADS)

Lee, Jun-Ki; Kwon, Yong-Ju

2011-04-01

This study investigated the neural correlates of experts and novices during biological object pattern detection using an fMRI approach in order to reveal the neural correlates of a biologist's superior pattern discovery ability. Sixteen healthy male participants (8 biologists and 8 non-biologists) volunteered for the study. Participants were shown fifteen series of organism pictures and asked to detect patterns amid stimulus pictures. Primary findings showed significant activations in the right middle temporal gyrus and inferior parietal lobule amongst participants in the biologist (expert) group. Interestingly, the left superior temporal gyrus was activated in participants from the non-biologist (novice) group. These results suggested that superior pattern discovery ability could be related to a functional facilitation of the parieto-temporal network, which is particularly driven by the right middle temporal gyrus and inferior parietal lobule in addition to the recruitment of additional brain regions. Furthermore, the functional facilitation of the network might actually pertain to high coherent processing skills and visual working memory capacity. Hence, study results suggested that adept scientific thinking ability can be detected by neuronal substrates, which may be used as criteria for developing and evaluating a brain-based science curriculum and test instrument.

Multitask assessment of roads and vehicles network (MARVN)

NASA Astrophysics Data System (ADS)

Yang, Fang; Yi, Meng; Cai, Yiran; Blasch, Erik; Sullivan, Nichole; Sheaff, Carolyn; Chen, Genshe; Ling, Haibin

2018-05-01

Vehicle detection in wide area motion imagery (WAMI) has drawn increasing attention from the computer vision research community in recent decades. In this paper, we present a new architecture for vehicle detection on road using multi-task network, which is able to detect and segment vehicles, estimate their pose, and meanwhile yield road isolation for a given region. The multi-task network consists of three components: 1) vehicle detection, 2) vehicle and road segmentation, and 3) detection screening. Segmentation and detection components share the same backbone network and are trained jointly in an end-to-end way. Unlike background subtraction or frame differencing based methods, the proposed Multitask Assessment of Roads and Vehicles Network (MARVN) method can detect vehicles which are slowing down, stopped, and/or partially occluded in a single image. In addition, the method can eliminate the detections which are located at outside road using yielded road segmentation so as to decrease the false positive rate. As few WAMI datasets have road mask and vehicles bounding box anotations, we extract 512 frames from WPAFB 2009 dataset and carefully refine the original annotations. The resulting dataset is thus named as WAMI512. We extensively compare the proposed method with state-of-the-art methods on WAMI512 dataset, and demonstrate superior performance in terms of efficiency and accuracy.

Development of a β-Lactoglobulin Sensor Based on SPR for Milk Allergens Detection.

PubMed

Ashley, Jon; D'Aurelio, Roberta; Piekarska, Monika; Temblay, Jeff; Pleasants, Mike; Trinh, Linda; Rodgers, Thomas L; Tothill, Ibtisam E

2018-03-27

A sensitive and label-free surface plasmon resonance (SPR) based sensor was developed in this work for the detection of milk allergens. β-lactoglobulin (BLG) protein was used as the biomarker for cow milk detection. This is to be used directly in final rinse samples of cleaning in-place (CIP) systems of food manufacturers. The affinity assay was optimised and characterised before a standard curve was performed in pure buffer conditions, giving a detection limit of 0.164 µg mL -1 as a direct binding assay. The detection limit can be further enhanced through the use of a sandwich assay and amplification with nanomaterials. However, this was not required here, as the detection limit achieved exceeded the required allergen detection levels of 2 µg mL -1 for β-lactoglobulin. The binding affinities of the polyclonal antibody for BLG, expressed by the dissociation constant (K D ), were equal to 2.59 × 10 -9 M. The developed SPR-based sensor offers several advantages in terms of label-free detection, real-time measurements, potential on-line system and superior sensitivity when compared to ELISA-based techniques. The method is novel for this application and could be applied to wider food allergen risk management decision(s) in food manufacturing.

[Efficacy of storage phosphor-based digital mammography in diagnosis of breast cancer--comparison with film-screen mammography].

PubMed

Kitahama, H

1991-05-25

The aim of this study is to present efficacy of storage phosphor-based digital mammography (CR-mammography) in diagnosis of breast cancer. Ninety-seven cases with breast cancer including 44 cases less than 2 cm in macroscopic size (t1 cases) were evaluated using storage phosphor-based digital mammography (2000 x 2510 pixels by 10 bits). Abnormal findings on CR-mammography were detected in 86 cases (88.7%) of 97 women with breast cancer. Sensitivity of CR-mammography was 88.7%. It was superior to that of film-screen mammography. On t1 breast cancer cases, sensitivity on CR-mammography was 88.6%. False negative rate in t1 breast cancer cases was reduced by image processing using CR-mammography. To evaluate microcalcifications, CR-mammograms and film-screen mammograms were investigated in 22 cases of breast cancer proven pathologically the existence of microcalcifications and 11 paraffin tissue blocks of breast cancer. CR-mammography was superior to film-screen mammography in recognizing of microcalcifications. As regards the detectability for the number and the shape of microcalcifications, CR-mammography was equivalent to film-screen mammography. Receiver operating characteristic (ROC) analysis by eight observers was performed for CR-mammography and film-screen mammography with 54 breast cancer patients and 54 normal cases. The detectability of abnormal findings of breast cancer on CR-mammography (ROC area = 0.91) was better than that on film-screen mammography (ROC area = 0.88) (p less than 0.05). Efficacy of storage phosphor-based digital mammography in diagnosis of breast cancer was discussed and demonstrated in this study.

Electrostimulation mapping of comprehension of auditory and visual words.

PubMed

Roux, Franck-Emmanuel; Miskin, Krasimir; Durand, Jean-Baptiste; Sacko, Oumar; Réhault, Emilie; Tanova, Rositsa; Démonet, Jean-François

2015-10-01

In order to spare functional areas during the removal of brain tumours, electrical stimulation mapping was used in 90 patients (77 in the left hemisphere and 13 in the right; 2754 cortical sites tested). Language functions were studied with a special focus on comprehension of auditory and visual words and the semantic system. In addition to naming, patients were asked to perform pointing tasks from auditory and visual stimuli (using sets of 4 different images controlled for familiarity), and also auditory object (sound recognition) and Token test tasks. Ninety-two auditory comprehension interference sites were observed. We found that the process of auditory comprehension involved a few, fine-grained, sub-centimetre cortical territories. Early stages of speech comprehension seem to relate to two posterior regions in the left superior temporal gyrus. Downstream lexical-semantic speech processing and sound analysis involved 2 pathways, along the anterior part of the left superior temporal gyrus, and posteriorly around the supramarginal and middle temporal gyri. Electrostimulation experimentally dissociated perceptual consciousness attached to speech comprehension. The initial word discrimination process can be considered as an "automatic" stage, the attention feedback not being impaired by stimulation as would be the case at the lexical-semantic stage. Multimodal organization of the superior temporal gyrus was also detected since some neurones could be involved in comprehension of visual material and naming. These findings demonstrate a fine graded, sub-centimetre, cortical representation of speech comprehension processing mainly in the left superior temporal gyrus and are in line with those described in dual stream models of language comprehension processing. Copyright © 2015 Elsevier Ltd. All rights reserved.

Diagnosis of gastrointestinal parasites in reptiles: comparison of two coprological methods

PubMed Central

2014-01-01

Background Exotic reptiles have become increasingly common domestic pets worldwide and are well known to be carriers of different parasites including some with zoonotic potential. The need of accurate diagnosis of gastrointestinal endoparasite infections in domestic reptiles is therefore essential, not only for the well-being of captive reptiles but also for the owners. Here, two different approaches for the detection of parasite stages in reptile faeces were compared: a combination of native and iodine stained direct smears together with a flotation technique (CNF) versus the standard SAF-method. Results A total of 59 different reptile faeces (20 lizards, 22 snakes, 17 tortoises) were coprologically analyzed by the two methods for the presence of endoparasites. Analyzed reptile faecal samples contained a broad spectrum of parasites (total occurence 93.2%, n = 55) including different species of nematodes (55.9%, n = 33), trematodes (15.3%, n = 9), pentastomids (3.4%, n = 2) and protozoans (47.5%, n = 28). Associations between the performances of both methods to detect selected single parasite stages or groups of such were evaluated by Fisher's exact test and marginal homogeneity was tested by the McNemar test. In 88.1% of all examined samples (n = 52, 95% confidence interval [CI] = 77.1 - 95.1%) the two diagnostic methods rendered differing results, and the McNemar test for paired observations showed highly significant differences of the detection frequency (P < 0.0001). Conclusion The combination of direct smears/flotation proved superior in the detection of flagellates trophozoites, coccidian oocysts and nematode eggs, especially those of oxyurids. SAF-technique was superior in detecting larval stages and trematode eggs, but this advantage failed to be statistically significant (P = 0.13). Therefore, CNF is the recommended method for routine faecal examination of captive reptiles while the SAF-technique is advisable as additional measure particularly for wild caught animals and individuals which are to be introduced into captive collections. PMID:25299119

Phase sensitive reconstruction of T1-weighted inversion recovery in the evaluation of the cervical cord lesions in multiple Sclerosis; is it similarly eligible in 1.5 T magnet fields?

PubMed

Shayganfar, A; Sarrami, A H; Fathi, S; Shaygannejad, V; Shamsian, S

2018-04-22

In primary studies with 3 T Magnets, phase sensitive reconstruction of T1-weighted inversion recovery (PSIR) have showed ability to depict the cervical multiple sclerosis (MS) lesions some of which may not be detected by short tau inversion recovery (STIR). Regarding to more availability of 1.5 T MRI, this study was designed to evaluate the eligibility of PSIR in 1.5 T for detection of spinal cord MS lesions. In a study between September 2016 till March 2017 the patients with proven diagnosis of MS enrolled to the study. The standard protocol (sagittal STIR and T2W FSE and axial T2W FSE) as well as sagittal PSIR sequences were performed using a 1.5 T magnet. The images were studied and the lesions were localized and recorded as sharp or faint on each sequence. Of 25 patients (22 females and 3 males, with mean age of 33.5 ± 9.8 years and mean disease duration of 5.4 ± 3.9 years) 69 lesions in STIR, 53 lesions in T2W FSE, 47 lesions in Magnitude reconstruction of PSIR (Magnitude), and 30 lesions in phase sensitive (real) reconstruction PSIR were detected. A Wilcoxon signed-rank test showed STIR has a statistically significant higher detection rate of the plaques rather than other three sequences. (STIR and T2W FSE, Z = -4.000, p < 0.0001, STIR and Magnitude, Z = -4.690, p < 0.0001, STIR and PSIR, Z = -6.245, p = 0.002) Also, STIR had a statistically significant superiority in the boundary definition of the plaques rather than other three sequences. This study shows that in the setting of a 1.5 T magnet field, STIR significantly has a superiority over both of the PSIR reconstructions (i.e. real and magnitude) for the detection as well as the boundary definition of the cervical cord lesions of MS. These results have a good relevance to clinical practice by using MRI scanners and sequences routinely available, however, it is discrepant with other reports performed by 3 T Magnet fields. Copyright © 2018 Elsevier B.V. All rights reserved.

Amorphous Red Phosphorus Embedded in Sandwiched Porous Carbon Enabling Superior Sodium Storage Performances.

PubMed

Wu, Ying; Liu, Zheng; Zhong, Xiongwu; Cheng, Xiaolong; Fan, Zhuangjun; Yu, Yan

2018-03-01

The red P anode for sodium ion batteries has attracted great attention recently due to the high theoretical capacity, but the poor intrinsic electronic conductivity and large volume expansion restrain its widespread applications. Herein, the red P is successfully encapsulated into the cube shaped sandwich-like interconnected porous carbon building (denoted as P@C-GO/MOF-5) via the vaporization-condensation method. Superior cycling stability (high capacity retention of about 93% at 2 A g -1 after 100 cycles) and excellent rate performance (502 mAh g -1 at 10 A g -1 ) can be obtained for the P@C-GO/MOF-5 electrode. The superior electrochemical performance can be ascribed to the successful incorporation of red P into the unique carbon matrix with large surface area and pore volume, interconnected porous structure, excellent electronic conductivity and superior structural stability. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Surveillance for vancomycin-resistant enterococci: type, rates, costs, and implications.

PubMed

Shadel, Brooke N; Puzniak, Laura A; Gillespie, Kathleen N; Lawrence, Steven J; Kollef, Marin; Mundy, Linda M

2006-10-01

To evaluate 2 active surveillance strategies for detection of enteric vancomycin-resistant enterococci (VRE) in an intensive care unit (ICU). Thirty-month prospective observational study. ICU at a university-affiliated referral center. All patients with an ICU stay of 24 hours or more were eligible for the study. Clinical active surveillance (CAS), involving culture of a rectal swab specimen for detection of VRE, was performed on admission, weekly while the patient was in the ICU, and at discharge. Laboratory-based active surveillance (LAS), involving culture of a stool specimen for detection of VRE, was performed on stool samples submitted for Clostridium difficile toxin detection. Enteric colonization with VRE was detected in 309 (17%) of 1,872 patients. The CAS method initially detected 280 (91%) of the 309 patients colonized with VRE, compared with 25 patients (8%) detected by LAS; colonization in 4 patients (1%) was initially detected by analysis of other clinical specimens. Most patients with colonization (76%) would have gone undetected by LAS alone, whereas use of the CAS method exclusively would have missed only 3 patients (1%) who were colonized. CAS cost Dollars 1,913 per month, or Dollars 57,395 for the 30-month study period. Cost savings of CAS from preventing cases of VRE colonization and bacteremia were estimated to range from Dollars 56,258 to Dollars 303,334 per month. A patient-based CAS strategy for detection of enteric colonization with VRE was superior to LAS. In this high-risk setting, CAS appeared to be the most efficient and cost-effective surveillance method. The modest costs of CAS were offset by the averted costs associated with the prevention of VRE colonization and bacteremia.

[Use of new tools for controlling triatomines in different entomologic situations in the American continent].

PubMed

Oliveira Filho, A M

1997-01-01

The field results of new tools for triatomine control developed under the sponsorship of WHO/TDR are reported: a) A slow-release "paint" containing malathion; b) fumigant cans containing cypermethrin and DDVP, and c) sensor boxes for the detection of triatomine infestations. Field assays were performed in Chile, Honduras and Paraguay against Triatoma infestans, T. dimidiata and Rhodnius prolixus, accordingly to a standard protocol designed by a WHO experts committee. Preliminary 6 months post-treatment results for the three countries show an efficient control when insecticide paints were used indoors and in the peridomicilium, keeping reinfestation near zero. The final results presented for Chile two years post-treatment confirmed the superiority of the slow-release "paints". Sensor boxes were less effective than man/hour captures in the detection of infested houses.

Morphological and radiological study of ossified superior transverse scapular ligament as potential risk factor of suprascapular nerve entrapment.

PubMed

Polguj, Michał; Sibiński, Marcin; Grzegorzewski, Andrzej; Waszczykowski, Michał; Majos, Agata; Topol, Mirosław

2014-01-01

The suprascapular notch is covered superiorly by the superior transverse scapular ligament. This region is the most common place of suprascapular nerve entrapment formation. The study was performed on 812 specimens: 86 dry scapulae, 104 formalin-fixed cadaveric shoulders, and 622 computer topography scans of scapulae. In the cases with completely ossified superior transverse scapular ligament, the following measurements were performed: proximal and distal width of the bony bridge, middle transverse and vertical diameter of the suprascapular foramen, and area of the suprascapular foramen. An ossified superior transverse scapular ligament was observed more often in men and in the right scapula. The mean age of the subjects with a completely ossified superior transverse scapular ligament was found to be similar than in those without ossification. The ossified band-shaped type of superior transverse scapular ligament was more common than the fan-shaped type and reduced the space below the ligament to a significantly greater degree. The ossified band-shaped type should be taken into consideration as a potential risk factor in the formation of suprascapular nerve entrapment. It could explain the comparable frequency of neuropathy in various populations throughout the world despite the significant differences between them in occurrence of ossified superior transverse scapular ligament.

More than Just Another Face in the Crowd: Evidence for an "Angry Superiority Effect" in Children with and without Autism

ERIC Educational Resources Information Center

Rosset, Delphine; Santos, Andreia; Da Fonseca, David; Rondan, Cecilie; Poinso, Francois; Deruelle, Christine

2011-01-01

The angry superiority effect refers to more efficient way individuals detect angry relative to happy faces in a crowd. Given their socio-emotional deficits, children with autism spectrum disorders (ASD) may be impervious to this effect. Thirty children with ASD and 30 matched-typically developing children were presented with a visual search task,…

Aging and the Picture Superiority Effect in Recall.

ERIC Educational Resources Information Center

Winograd, Eugene; And Others

1982-01-01

Compared verbal and visual encoding using the picture superiority effect. One experiment found an interaction between age and type of material. In other experiments, the picture superiority effect was found in both age groups with no interaction. Performing a semantic-orienting task had no effect on recall. (Author/RC)

Comparison of gonioscopy and anterior segment ocular coherence tomography in detecting angle closure in different quadrants of the anterior chamber angle.

PubMed

Sakata, Lisandro M; Lavanya, Raghavan; Friedman, David S; Aung, Han T; Gao, Hong; Kumar, Rajesh S; Foster, Paul J; Aung, Tin

2008-05-01

To compare the performance of gonioscopy and anterior segment (AS) optical coherence tomography (OCT) in detecting angle closure in the different quadrants of the anterior chamber angle (ACA). Cross-sectional observational study. Five hundred two consecutive subjects more than 50 years of age with no previous ophthalmic problems recruited from a community clinic in Singapore. All subjects underwent gonioscopy and AS OCT imaging in the dark. Using gonioscopy, the ACA was graded using the Scheie system by a single examiner masked to AS OCT findings. The ACA in a particular quadrant was classified as closed if the posterior trabecular meshwork could not be seen on gonioscopy. A closed ACA on AS OCT imaging was defined by the presence of any contact between the iris and angle wall anterior to the scleral spur. After excluding eyes with poor image quality, a total of 423 right eyes were included in the analysis. A closed angle in at least 1 quadrant was observed in 59% of the eyes by AS OCT and in 33% of the eyes by gonioscopy (P<0.001), with fair agreement between the two methods (kappa = 0.40). The frequency of closed angles by AS OCT and gonioscopy were 48% versus 29% superiorly, 43% versus 22% inferiorly, 18% versus 14% nasally, and 12% versus 20% temporally, respectively. Of the 119 of 1692 quadrants that were closed on gonioscopy but open on AS OCT, a steep iris profile was present in 61 (51%) of 119 quadrants on AS OCT, and of the 276 of 1692 quadrants that were open on gonioscopy but closed on AS OCT, 196 (71%) of 276 quadrants showed short iridoangle contact on AS OCT. The highest rates of closed angles on gonioscopy and AS OCT images were observed in the superior quadrant. Anterior segment OCT tended to detect more closed ACAs than gonioscopy, particularly in the superior and inferior quadrants. Variations in the iris profile and level of iridoangle contact also may explain some of the differences seen between gonioscopy and AS OCT.

Use of ionic liquids as headspace gas chromatography diluents for the analysis of residual solvents in pharmaceuticals.

PubMed

Nacham, Omprakash; Ho, Tien D; Anderson, Jared L; Webster, Gregory K

2017-10-25

In this study, two ionic liquids (ILs), 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([BMIM][NTf 2 ]) and trihexyltetradecylphosphonium bis[(trifluoromethyl)sulfonyl]imide ([P 66614 ][NTf 2 ]) were examined as contemporary diluents for residual solvent analysis using static headspace gas chromatography (SHS-GC) coupled with flame ionization detection (FID). ILs are a class of non-molecular solvents featuring negligible vapor pressure and high thermal stabilities. Owing to these favorable properties, ILs have potential to enable superior sensitivity and reduced interference, compared to conventional organic diluents, at high headspace incubation temperatures. By employing the [BMIM][NTf 2 ] IL as a diluent, a 25-fold improvement in limit of detection (LOD) was observed with respect to traditional HS-GC diluents, such as N-methylpyrrolidone (NMP). The established IL-based method demonstrated LODs ranging from 5.8 parts-per-million (ppm) to 20ppm of residual solvents in drug substances. The optimization of headspace extraction conditions was performed prior to method validation. An incubation temperature of 140°C and a 15min incubation time provided the best sensitivity for the analysis. Under optimized experimental conditions, the mass of residual solvents partitioned in the headspace was higher when using [BMIM][NTf 2 ] than NMP as a diluent. The analytical performance was demonstrated by determining the repeatability, accuracy, and linearity of the method. Linear ranges of up to two orders of magnitude were obtained for class 3 solvents. Excellent analyte recoveries were obtained in the presence of three different active pharmaceutical ingredients. Owing to its robustness, high throughput, and superior sensitivity, the HS-GC IL-based method can be used as an alternative to existing residual solvent methods. Copyright © 2017 Elsevier B.V. All rights reserved.

Scalable Static and Dynamic Community Detection Using Grappolo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Halappanavar, Mahantesh; Lu, Hao; Kalyanaraman, Anantharaman

Graph clustering, popularly known as community detection, is a fundamental kernel for several applications of relevance to the Defense Advanced Research Projects Agency’s (DARPA) Hierarchical Identify Verify Exploit (HIVE) Pro- gram. Clusters or communities represent natural divisions within a network that are densely connected within a cluster and sparsely connected to the rest of the network. The need to compute clustering on large scale data necessitates the development of efficient algorithms that can exploit modern architectures that are fundamentally parallel in nature. How- ever, due to their irregular and inherently sequential nature, many of the current algorithms for community detectionmore » are challenging to parallelize. In response to the HIVE Graph Challenge, we present several parallelization heuristics for fast community detection using the Louvain method as the serial template. We implement all the heuristics in a software library called Grappolo. Using the inputs from the HIVE Challenge, we demonstrate superior performance and high quality solutions based on four parallelization heuristics. We use Grappolo on static graphs as the first step towards community detection on streaming graphs.« less

An adaptive confidence limit for periodic non-steady conditions fault detection

NASA Astrophysics Data System (ADS)

Wang, Tianzhen; Wu, Hao; Ni, Mengqi; Zhang, Milu; Dong, Jingjing; Benbouzid, Mohamed El Hachemi; Hu, Xiong

2016-05-01

System monitoring has become a major concern in batch process due to the fact that failure rate in non-steady conditions is much higher than in steady ones. A series of approaches based on PCA have already solved problems such as data dimensionality reduction, multivariable decorrelation, and processing non-changing signal. However, if the data follows non-Gaussian distribution or the variables contain some signal changes, the above approaches are not applicable. To deal with these concerns and to enhance performance in multiperiod data processing, this paper proposes a fault detection method using adaptive confidence limit (ACL) in periodic non-steady conditions. The proposed ACL method achieves four main enhancements: Longitudinal-Standardization could convert non-Gaussian sampling data to Gaussian ones; the multiperiod PCA algorithm could reduce dimensionality, remove correlation, and improve the monitoring accuracy; the adaptive confidence limit could detect faults under non-steady conditions; the fault sections determination procedure could select the appropriate parameter of the adaptive confidence limit. The achieved result analysis clearly shows that the proposed ACL method is superior to other fault detection approaches under periodic non-steady conditions.

A Sea-Sky Line Detection Method for Unmanned Surface Vehicles Based on Gradient Saliency.

PubMed

Wang, Bo; Su, Yumin; Wan, Lei

2016-04-15

Special features in real marine environments such as cloud clutter, sea glint and weather conditions always result in various kinds of interference in optical images, which make it very difficult for unmanned surface vehicles (USVs) to detect the sea-sky line (SSL) accurately. To solve this problem a saliency-based SSL detection method is proposed. Through the computation of gradient saliency the line features of SSL are enhanced effectively, while other interference factors are relatively suppressed, and line support regions are obtained by a region growing method on gradient orientation. The SSL identification is achieved according to region contrast, line segment length and orientation features, and optimal state estimation of SSL detection is implemented by introducing a cubature Kalman filter (CKF). In the end, the proposed method is tested on a benchmark dataset from the "XL" USV in a real marine environment, and the experimental results demonstrate that the proposed method is significantly superior to other state-of-the-art methods in terms of accuracy rate and real-time performance, and its accuracy and stability are effectively improved by the CKF.

Efficient Gas-Sensing for Formaldehyde with 3D Hierarchical Co3O4 Derived from Co5-Based MOF Microcrystals.

PubMed

Zhou, Wei; Wu, Ya-Pan; Zhao, Jun; Dong, Wen-Wen; Qiao, Xiu-Qing; Hou, Dong-Fang; Bu, Xianhui; Li, Dong-Sheng

2017-11-20

Detecting formaldehyde at low operating temperature and maintaining long-term stability are of great significance. In this work, a hierarchical Co 3 O 4 nanostructure has been fabricated by calcining Co 5 -based metal-organic framework (MOF) microcrystals. Co 3 O 4 -350 particles were used for efficient gas-sensing for the detecting of formaldehyde vapor at lower working temperature (170 °C), low detection limit of 10 ppm, and long-term stability (30 days), which not only is the optimal value among all reported pure Co 3 O 4 sensing materials for the detection of formaldehyde but also is superior to that of majority of Co 3 O 4 -based composites. Such extraordinarily efficient properties might be resulted from hierarchically structures, larger surface area and unique pore structure. This strategy is further confirmed that MOFs, especially Co-clusters MOFs, could be used as precursor to synthesize 3D nanostructure metal oxide materials with high-performance, which possess high porosity and more active sites and shorter ionic diffusion lengths.

Contrast Invariant Interest Point Detection by Zero-Norm LoG Filter.

PubMed

Zhenwei Miao; Xudong Jiang; Kim-Hui Yap

2016-01-01

The Laplacian of Gaussian (LoG) filter is widely used in interest point detection. However, low-contrast image structures, though stable and significant, are often submerged by the high-contrast ones in the response image of the LoG filter, and hence are difficult to be detected. To solve this problem, we derive a generalized LoG filter, and propose a zero-norm LoG filter. The response of the zero-norm LoG filter is proportional to the weighted number of bright/dark pixels in a local region, which makes this filter be invariant to the image contrast. Based on the zero-norm LoG filter, we develop an interest point detector to extract local structures from images. Compared with the contrast dependent detectors, such as the popular scale invariant feature transform detector, the proposed detector is robust to illumination changes and abrupt variations of images. Experiments on benchmark databases demonstrate the superior performance of the proposed zero-norm LoG detector in terms of the repeatability and matching score of the detected points as well as the image recognition rate under different conditions.

Comprehensive thin-layer chromatography mass spectrometry of flavanols from Juniperus communis L. and Punica granatum L.

PubMed

Smrke, Samo; Vovk, Irena

2013-05-10

The coupling of thin-layer chromatography with mass spectrometry (TLC-MS) for the analysis of monomeric flavanols and proanthocyanidins in samples presented as complex matrices has been studied. The elution conditions for TLC-MS were optimised and full scans were compared with selected reaction monitoring for the MS detection of compounds. The performance of silica gel and cellulose plates with different developing solvents in TLC-MS was assessed. Cellulose plates provided superior sensitivity while ionisation suppression was encountered with silica plates. The use of a HILIC guard column beyond the elution head was found to facilitate detection of monomer compounds on silica plates. A new comprehensive TLC×MS procedure for screening flavanols in the entire chromatogram was developed as an alternative to the use of 4-dimethylaminocinnamaldehyde to determine the locations of compounds on the plate. This new procedure was applied to detect flavanols in the peel of Punica granatum L. fruits and in seeds of Juniperus communis L., in which flavanols and proanthocyanidin dimers and trimers were detected for the first time. Copyright © 2013 Elsevier B.V. All rights reserved.

A Plasmonic Mass Spectrometry Approach for Detection of Small Nutrients and Toxins

NASA Astrophysics Data System (ADS)

Wu, Shu; Qian, Linxi; Huang, Lin; Sun, Xuming; Su, Haiyang; Gurav, Deepanjali D.; Jiang, Mawei; Cai, Wei; Qian, Kun

2018-07-01

Nutriology relies on advanced analytical tools to study the molecular compositions of food and provide key information on sample quality/safety. Small nutrients detection is challenging due to the high diversity and broad dynamic range of molecules in food samples, and a further issue is to track low abundance toxins. Herein, we developed a novel plasmonic matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) approach to detect small nutrients and toxins in complex biological emulsion samples. Silver nanoshells (SiO2@Ag) with optimized structures were used as matrices and achieved direct analysis of 6 nL of human breast milk without any enrichment or separation. We performed identification and quantitation of small nutrients and toxins with limit-of-detection down to 0.4 pmol (for melamine) and reaction time shortened to minutes, which is superior to the conventional biochemical method currently in use. The developed approach contributes to the near-future application of MALDI MS in a broad field and personalized design of plasmonic materials for real-case bio-analysis.[Figure not available: see fulltext.

Capillary-driven surface-enhanced Raman scattering (SERS)-based microfluidic chip for abrin detection

NASA Astrophysics Data System (ADS)

Yang, Hao; Deng, Min; Ga, Shan; Chen, Shouhui; Kang, Lin; Wang, Junhong; Xin, Wenwen; Zhang, Tao; You, Zherong; An, Yuan; Wang, Jinglin; Cui, Daxiang

2014-03-01

Herein, we firstly demonstrate the design and the proof-of-concept use of a capillary-driven surface-enhanced Raman scattering (SERS)-based microfluidic chip for abrin detection. The micropillar array substrate was etched and coated with a gold film by microelectromechanical systems (MEMS) process to integrate into a lateral flow test strip. The detection of abrin solutions of various concentrations was performed by the as-prepared microfluidic chip. It was shown that the correlation between the abrin concentration and SERS signal was found to be linear within the range of 0.1 ng/mL to 1 μg/mL with a limit of detection of 0.1 ng/mL. Our microfluidic chip design enhanced the operability of SERS-based immunodiagnostic techniques, significantly reducing the complication and cost of preparation as compared to previous SERS-based works. Meanwhile, this design proved the superiority to conventional lateral flow test strips in respect of both sensitivity and quantitation and showed great potential in the diagnosis and treatment for abrin poisoning as well as on-site screening of abrin-spiked materials.

Ground-based remote sensing of HDO/H2O ratio profiles: introduction and validation of an innovative retrieval approach

NASA Astrophysics Data System (ADS)

Schneider, M.; Hase, F.; Blumenstock, T.

2006-10-01

We propose an innovative approach for analysing ground-based FTIR spectra which allows us to detect variabilities of lower and middle/upper tropospheric HDO/H2O ratios. We show that the proposed method is superior to common approaches. We estimate that lower tropospheric HDO/H2O ratios can be detected with a noise to signal ratio of 15% and middle/upper tropospheric ratios with a noise to signal ratio of 50%. The method requires the inversion to be performed on a logarithmic scale and to introduce an inter-species constraint. While common methods calculate the isotope ratio posterior to an independent, optimal estimation of the HDO and H2O profile, the proposed approach is an optimal estimator for the ratio itself. We apply the innovative approach to spectra measured continuously during 15 months and present, for the first time, an annual cycle of tropospheric HDO/H2O ratio profiles as detected by ground-based measurements. Outliers in the detected middle/upper tropospheric ratios are interpreted by backward trajectories.

Ground-based remote sensing of HDO/H2O ratio profiles: introduction and validation of an innovative retrieval approach

NASA Astrophysics Data System (ADS)

Schneider, M.; Hase, F.; Blumenstock, T.

2006-06-01

We propose an innovative approach for analysing ground-based FTIR spectra which allows us to detect variabilities of lower and middle/upper tropospheric HDO/H2O ratios. We show that the proposed method is superior to common approaches. We estimate that lower tropospheric HDO/H2O ratios can be detected with a noise to signal ratio of 15% and middle/upper tropospheric ratios with a noise to signal ratio of 50%. The method requires the inversion to be performed on a logarithmic scale and to introduce an inter-species constraint. While common methods calculate the isotope ratio posterior to an independent, optimal estimation of the HDO and H2O profile, the proposed approach is an optimal estimator for the ratio itself. We apply the innovative approach to spectra measured continuously during 15 months and present, for the first time, an annual cycle of tropospheric HDO/H2O ratio profiles as detected by ground-based measurements. Outliers in the detected middle/upper tropospheric ratios are interpreted by backward trajectories.

A cooperative game framework for detecting overlapping communities in social networks

NASA Astrophysics Data System (ADS)

Jonnalagadda, Annapurna; Kuppusamy, Lakshmanan

2018-02-01

Community detection in social networks is a challenging and complex task, which received much attention from researchers of multiple domains in recent years. The evolution of communities in social networks happens merely due to the self-interest of the nodes. The interesting feature of community structure in social networks is the multi membership of the nodes resulting in overlapping communities. Assuming the nodes of the social network as self-interested players, the dynamics of community formation can be captured in the form of a game. In this paper, we propose a greedy algorithm, namely, Weighted Graph Community Game (WGCG), in order to model the interactions among the self-interested nodes of the social network. The proposed algorithm employs the Shapley value mechanism to discover the inherent communities of the underlying social network. The experimental evaluation on the real-world and synthetic benchmark networks demonstrates that the performance of the proposed algorithm is superior to the state-of-the-art overlapping community detection algorithms.

An Enzyme-Free Signal Amplification Technique for Ultrasensitive Colorimetric Assay of Disease Biomarkers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Haihang; Yang, Kuikun; Tao, Jing

Enzyme-based colorimetric assays have been widely used in research labs and clinical diagnosis for decades. Nevertheless, as constrained by the performance of enzymes, their detection sensitivity has not been substantially improved in recent years, which inhibits many critical applications such as early detection of cancers. In this work, we demonstrate an enzyme-free signal amplification technique, based on gold vesicles encapsulated with Pd-Ir nanoparticles as peroxidase mimics, for colorimetric assay of disease biomarkers with significantly enhanced sensitivity. This technique overcomes the intrinsic limitations of enzymes, thanks to the superior catalytic efficiency of peroxidase mimics and the efficient loading and release ofmore » these mimics. Using human prostate surface antigen as a model biomarker, we demonstrated that the enzyme-free assay could reach a limit of detection at the femtogram/mL level, which is over 10 3-fold lower than that of conventional enzyme-based assay when the same antibodies and similar procedure were used.« less

An Enzyme-Free Signal Amplification Technique for Ultrasensitive Colorimetric Assay of Disease Biomarkers

DOE PAGES

Ye, Haihang; Yang, Kuikun; Tao, Jing; ...

2017-01-30

Enzyme-based colorimetric assays have been widely used in research labs and clinical diagnosis for decades. Nevertheless, as constrained by the performance of enzymes, their detection sensitivity has not been substantially improved in recent years, which inhibits many critical applications such as early detection of cancers. In this work, we demonstrate an enzyme-free signal amplification technique, based on gold vesicles encapsulated with Pd-Ir nanoparticles as peroxidase mimics, for colorimetric assay of disease biomarkers with significantly enhanced sensitivity. This technique overcomes the intrinsic limitations of enzymes, thanks to the superior catalytic efficiency of peroxidase mimics and the efficient loading and release ofmore » these mimics. Using human prostate surface antigen as a model biomarker, we demonstrated that the enzyme-free assay could reach a limit of detection at the femtogram/mL level, which is over 10 3-fold lower than that of conventional enzyme-based assay when the same antibodies and similar procedure were used.« less

Rational design of binder-free noble metal/metal oxide arrays with nanocauliflower structure for wide linear range nonenzymatic glucose detection

PubMed Central

Li, Zhenzhen; Xin, Yanmei; Zhang, Zhonghai; Wu, Hongjun; Wang, Peng

2015-01-01

One-dimensional nanocomposites of metal-oxide and noble metal were expected to present superior performance for nonenzymatic glucose detection due to its good conductivity and high catalytic activity inherited from noble metal and metal oxide respectively. As a proof of concept, we synthesized gold and copper oxide (Au/CuO) composite with unique one-dimensional nanocauliflowers structure. Due to the nature of the synthesis method, no any foreign binder was needed in keeping either Au or CuO in place. To the best of our knowledge, this is the first attempt in combining metal oxide and noble metal in a binder-free style for fabricating nonenzymatic glucose sensor. The Au/CuO nanocauliflowers with large electrochemical active surface and high electrolyte contact area would promise a wide linear range and high sensitive detection of glucose with good stability and reproducibility due to its good electrical conductivity of Au and high electrocatalytic activity of CuO. PMID:26068705

Weak Fault Feature Extraction of Rolling Bearings Based on an Improved Kurtogram

PubMed Central

Chen, Xianglong; Feng, Fuzhou; Zhang, Bingzhi

2016-01-01

Kurtograms have been verified to be an efficient tool in bearing fault detection and diagnosis because of their superiority in extracting transient features. However, the short-time Fourier Transform is insufficient in time-frequency analysis and kurtosis is deficient in detecting cyclic transients. Those factors weaken the performance of the original kurtogram in extracting weak fault features. Correlated Kurtosis (CK) is then designed, as a more effective solution, in detecting cyclic transients. Redundant Second Generation Wavelet Packet Transform (RSGWPT) is deemed to be effective in capturing more detailed local time-frequency description of the signal, and restricting the frequency aliasing components of the analysis results. The authors in this manuscript, combining the CK with the RSGWPT, propose an improved kurtogram to extract weak fault features from bearing vibration signals. The analysis of simulation signals and real application cases demonstrate that the proposed method is relatively more accurate and effective in extracting weak fault features. PMID:27649171

Object-based detection of vehicles using combined optical and elevation data

NASA Astrophysics Data System (ADS)

Schilling, Hendrik; Bulatov, Dimitri; Middelmann, Wolfgang

2018-02-01

The detection of vehicles is an important and challenging topic that is relevant for many applications. In this work, we present a workflow that utilizes optical and elevation data to detect vehicles in remotely sensed urban data. This workflow consists of three consecutive stages: candidate identification, classification, and single vehicle extraction. Unlike in most previous approaches, fusion of both data sources is strongly pursued at all stages. While the first stage utilizes the fact that most man-made objects are rectangular in shape, the second and third stages employ machine learning techniques combined with specific features. The stages are designed to handle multiple sensor input, which results in a significant improvement. A detailed evaluation shows the benefits of our workflow, which includes hand-tailored features; even in comparison with classification approaches based on Convolutional Neural Networks, which are state of the art in computer vision, we could obtain a comparable or superior performance (F1 score of 0.96-0.94).

Facile synthesis of nanostructured TiNb2O7 anode materials with superior performance for high-rate lithium ion batteries.

PubMed

Lou, Shuaifeng; Ma, Yulin; Cheng, Xinqun; Gao, Jinlong; Gao, Yunzhi; Zuo, Pengjian; Du, Chunyu; Yin, Geping

2015-12-18

One-dimensional nanostructured TiNb2O7 was prepared by a simple solution-based process and subsequent thermal annealing. The obtained anode materials exhibited excellent electrochemical performance with superior reversible capacity, rate capability and cyclic stability.

Multi-modal information processing for visual workload relief

NASA Technical Reports Server (NTRS)

Burke, M. W.; Gilson, R. D.; Jagacinski, R. J.

1980-01-01

The simultaneous performance of two single-dimensional compensatory tracking tasks, one with the left hand and one with the right hand, is discussed. The tracking performed with the left hand was considered the primary task and was performed with a visual display or a quickened kinesthetic-tactual (KT) display. The right-handed tracking was considered the secondary task and was carried out only with a visual display. Although the two primary task displays had afforded equivalent performance in a critical tracking task performed alone, in the dual-task situation the quickened KT primary display resulted in superior secondary visual task performance. Comparisons of various combinations of primary and secondary visual displays in integrated or separated formats indicate that the superiority of the quickened KT display is not simply due to the elimination of visual scanning. Additional testing indicated that quickening per se also is not the immediate cause of the observed KT superiority.

Greater sensitivity of the cortical face processing system to perceptually-equated face detection

PubMed Central

Maher, S.; Ekstrom, T.; Tong, Y.; Nickerson, L.D.; Frederick, B.; Chen, Y.

2015-01-01

Face detection, the perceptual capacity to identify a visual stimulus as a face before probing deeper into specific attributes (such as its identity or emotion), is essential for social functioning. Despite the importance of this functional capacity, face detection and its underlying brain mechanisms are not well understood. This study evaluated the roles that the cortical face processing system, which is identified largely through studying other aspects of face perception, play in face detection. Specifically, we used functional magnetic resonance imaging (fMRI) to examine the activations of the fusifom face area (FFA), occipital face area (OFA) and superior temporal sulcus (STS) when face detection was isolated from other aspects of face perception and when face detection was perceptually-equated across individual human participants (n=20). During face detection, FFA and OFA were significantly activated, even for stimuli presented at perceptual-threshold levels, whereas STS was not. During tree detection, however, FFA and OFA were responsive only for highly salient (i.e., high contrast) stimuli. Moreover, activation of FFA during face detection predicted a significant portion of the perceptual performance levels that were determined psychophysically for each participant. This pattern of result indicates that FFA and OFA have a greater sensitivity to face detection signals and selectively support the initial process of face vs. non-face object perception. PMID:26592952

Oral-Fluid Thiol-Detection Test Identifies Underlying Active Periodontal Disease Not Detected by the Visual Awake Examination.

PubMed

Queck, Katherine E; Chapman, Angela; Herzog, Leslie J; Shell-Martin, Tamara; Burgess-Cassler, Anthony; McClure, George David

Periodontal disease in dogs is highly prevalent but can only be accurately diagnosed by performing an anesthetized oral examination with periodontal probing and dental radiography. In this study, 114 dogs had a visual awake examination of the oral cavity and were administered an oral-fluid thiol-detection test prior to undergoing a a full-mouth anesthetized oral examination and digital dental radiographs. The results show the visual awake examination underestimated the presence and severity of active periodontal disease. The thiol-detection test was superior to the visual awake examination at detecting the presence and severity of active periodontal disease and was an indicator of progression toward alveolar bone loss. The thiol-detection test detected active periodontal disease at early stages of development, before any visual cues were present, indicating the need for intervention to prevent periodontal bone loss. Early detection is important because without intervention, dogs with gingivitis (active periodontal disease) progress to irreversible periodontal bone loss (stage 2+). As suggested in the current AAHA guidelines, a thiol-detection test administered in conjunction with the visual awake examination during routine wellness examinations facilitates veterinarian-client communication and mitigates under-diagnosis of periodontal disease and underutilization of dental services. The thiol-detection test can be used to monitor the periodontal health status of the conscious patient during follow-up examinations based on disease severity.

In vitro performance of near infrared light transillumination at 780-nm and digital radiography for detection of non-cavitated approximal caries.

PubMed

Abogazalah, N; Eckert, G J; Ando, M

2017-08-01

To evaluate the ability of a Near Infrared Light Transillumination (NILT) device to detect non-cavitated approximal caries lesions; and to compare its performance to Digital Radiography (DR). Thirty human extracted premolars (sound to lesions into the outer one-third of dentin) were selected. Lesion depth was confirmed by micro-computed tomography (μ-CT). Teeth were mounted in a custom-made device to simulate approximal contact. DR and NILT (CariVu™, DEXIS, LLC, Hatfield, PA, USA) examinations were performed and repeated by three trained and calibrated examiners. Sensitivity, specificity, area under ROC curve (A z ), inter- and intra-class correlation coefficients (ICCs) for each method, and correlation among the methods were determined. ICCs for intra-/inter-examiner agreement were substantial for NILT (0.69/0.64), and moderate for DR (0.52/0.48). Sensitivity/specificity for NILT and DR were 0.68/0.93 and 0.50/0.64, respectively. A z for NILT was 0.81, while for DR it was 0.61. Spearman correlation coefficient with μ-CT for NILT (0.65, p<0.001) demonstrated moderate association, while that of DR suggested no association (0.19, p=0.289). Within the limitations of this in vitro study, NILT demonstrated a potential for early approximal caries detection. NILT and DR performed the same regarding the accuracy for non-cavitated approximal caries detection; however, NILT was superior to DR in terms of repeatability, agreement and correlation with μ-CT. A commercial version of NILT was recently introduced as a non-irradiative adjunctive caries detection method. It uses near infrared (NIR) light at 780-nm to transilluminate teeth and captures live images from the occlusal surface. This study demonstrates that NILT can be used as an alternative to radiography for non-cavitated approximal caries detection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ultrahigh performance supercritical fluid chromatography of lipophilic compounds with application to synthetic and commercial biodiesel.

PubMed

Ashraf-Khorassani, M; Yang, J; Rainville, P; Jones, M D; Fountain, K J; Isaac, G; Taylor, L T

2015-03-01

Ultrahigh performance supercritical fluid chromatography (UHPSFC) in combination with sub-2μm particles and either diode array ultraviolet (UV), evaporative light scattering, (ELSD), or mass spectrometric (MS) detection has been shown to be a valuable technique for the determination of acylglycerols in soybean, corn, sesame, and tobacco seed oils. Excellent resolution on an un-endcapped single C18 column (3.0mm×150mm) with a mobile phase gradient of acetonitrile and carbon dioxide in as little as 10min served greatly as an improvement on first generation packed column SFC instrumentation. Unlike high resolution gas chromatography and high performance liquid chromatography with mass spectrometric detection, UHPSFC/MS was determined to be a superior analytical tool for both separation and detection of mono-, di-, and tri-acylglycerols as well as free glycerol itself in biodiesel without derivatization. Baseline separation of residual tri-, di-, and mono-acylglycerols alongside glycerol at 0.05% (w/w) was easily obtained employing packed column SFC. The new analytical methodology was applied to both commercial B100 biodiesel (i.e. fatty acid methyl esters) derived from vegetable oil and to an "in-house" synthetic biodiesel (i.e. fatty acid ethyl esters) derived from tobacco seed oil and ethanol both before and after purification via column chromatography on bare silica. Copyright © 2014 Elsevier B.V. All rights reserved.

Clinical Evaluation of a Loop-Mediated Amplification Kit for Diagnosis of Imported Malaria

PubMed Central

Polley, Spencer D.; González, Iveth J.; Mohamed, Deqa; Daly, Rosemarie; Bowers, Kathy; Watson, Julie; Mewse, Emma; Armstrong, Margaret; Gray, Christen; Perkins, Mark D.; Bell, David; Kanda, Hidetoshi; Tomita, Norihiro; Kubota, Yutaka; Mori, Yasuyoshi; Chiodini, Peter L.; Sutherland, Colin J.

2013-01-01

Background. Diagnosis of malaria relies on parasite detection by microscopy or antigen detection; both fail to detect low-density infections. New tests providing rapid, sensitive diagnosis with minimal need for training would enhance both malaria diagnosis and malaria control activities. We determined the diagnostic accuracy of a new loop-mediated amplification (LAMP) kit in febrile returned travelers. Methods. The kit was evaluated in sequential blood samples from returned travelers sent for pathogen testing to a specialist parasitology laboratory. Microscopy was performed, and then malaria LAMP was performed using Plasmodium genus and Plasmodium falciparum–specific tests in parallel. Nested polymerase chain reaction (PCR) was performed on all samples as the reference standard. Primary outcome measures for diagnostic accuracy were sensitivity and specificity of LAMP results, compared with those of nested PCR. Results. A total of 705 samples were tested in the primary analysis. Sensitivity and specificity were 98.4% and 98.1%, respectively, for the LAMP P. falciparum primers and 97.0% and 99.2%, respectively, for the Plasmodium genus primers. Post hoc repeat PCR analysis of all 15 tests with discrepant results resolved 4 results in favor of LAMP, suggesting that the primary analysis had underestimated diagnostic accuracy. Conclusions. Malaria LAMP had a diagnostic accuracy similar to that of nested PCR, with a greatly reduced time to result, and was superior to expert microscopy. PMID:23633403

Cognitive foundations for model-based sensor fusion

NASA Astrophysics Data System (ADS)

Perlovsky, Leonid I.; Weijers, Bertus; Mutz, Chris W.

2003-08-01

Target detection, tracking, and sensor fusion are complicated problems, which usually are performed sequentially. First detecting targets, then tracking, then fusing multiple sensors reduces computations. This procedure however is inapplicable to difficult targets which cannot be reliably detected using individual sensors, on individual scans or frames. In such more complicated cases one has to perform functions of fusing, tracking, and detecting concurrently. This often has led to prohibitive combinatorial complexity and, as a consequence, to sub-optimal performance as compared to the information-theoretic content of all the available data. It is well appreciated that in this task the human mind is by far superior qualitatively to existing mathematical methods of sensor fusion, however, the human mind is limited in the amount of information and speed of computation it can cope with. Therefore, research efforts have been devoted toward incorporating "biological lessons" into smart algorithms, yet success has been limited. Why is this so, and how to overcome existing limitations? The fundamental reasons for current limitations are analyzed and a potentially breakthrough research and development effort is outlined. We utilize the way our mind combines emotions and concepts in the thinking process and present the mathematical approach to accomplishing this in the current technology computers. The presentation will summarize the difficulties encountered by intelligent systems over the last 50 years related to combinatorial complexity, analyze the fundamental limitations of existing algorithms and neural networks, and relate it to the type of logic underlying the computational structure: formal, multivalued, and fuzzy logic. A new concept of dynamic logic will be introduced along with algorithms capable of pulling together all the available information from multiple sources. This new mathematical technique, like our brain, combines conceptual understanding with emotional evaluation and overcomes the combinatorial complexity of concurrent fusion, tracking, and detection. The presentation will discuss examples of performance, where computational speedups of many orders of magnitude were attained leading to performance improvements of up to 10 dB (and better).

Monitoring Poisson observations using combined applications of Shewhart and EWMA charts

NASA Astrophysics Data System (ADS)

Abujiya, Mu'azu Ramat

2017-11-01

The Shewhart and exponentially weighted moving average (EWMA) charts for nonconformities are the most widely used procedures of choice for monitoring Poisson observations in modern industries. Individually, the Shewhart EWMA charts are only sensitive to large and small shifts, respectively. To enhance the detection abilities of the two schemes in monitoring all kinds of shifts in Poisson count data, this study examines the performance of combined applications of the Shewhart, and EWMA Poisson control charts. Furthermore, the study proposes modifications based on well-structured statistical data collection technique, ranked set sampling (RSS), to detect shifts in the mean of a Poisson process more quickly. The relative performance of the proposed Shewhart-EWMA Poisson location charts is evaluated in terms of the average run length (ARL), standard deviation of the run length (SDRL), median run length (MRL), average ratio ARL (ARARL), average extra quadratic loss (AEQL) and performance comparison index (PCI). Consequently, all the new Poisson control charts based on RSS method are generally more superior than most of the existing schemes for monitoring Poisson processes. The use of these combined Shewhart-EWMA Poisson charts is illustrated with an example to demonstrate the practical implementation of the design procedure.

A Negative Selection Immune System Inspired Methodology for Fault Diagnosis of Wind Turbines.

PubMed

Alizadeh, Esmaeil; Meskin, Nader; Khorasani, Khashayar

2017-11-01

High operational and maintenance costs represent as major economic constraints in the wind turbine (WT) industry. These concerns have made investigation into fault diagnosis of WT systems an extremely important and active area of research. In this paper, an immune system (IS) inspired methodology for performing fault detection and isolation (FDI) of a WT system is proposed and developed. The proposed scheme is based on a self nonself discrimination paradigm of a biological IS. Specifically, the negative selection mechanism [negative selection algorithm (NSA)] of the human body is utilized. In this paper, a hierarchical bank of NSAs are designed to detect and isolate both individual as well as simultaneously occurring faults common to the WTs. A smoothing moving window filter is then utilized to further improve the reliability and performance of the FDI scheme. Moreover, the performance of our proposed scheme is compared with another state-of-the-art data-driven technique, namely the support vector machines (SVMs) to demonstrate and illustrate the superiority and advantages of our proposed NSA-based FDI scheme. Finally, a nonparametric statistical comparison test is implemented to evaluate our proposed methodology with that of the SVM under various fault severities.

Computer-aided diagnosis of cavernous malformations in brain MR images.

PubMed

Wang, Huiquan; Ahmed, S Nizam; Mandal, Mrinal

2018-06-01

Cavernous malformation or cavernoma is one of the most common epileptogenic lesions. It is a type of brain vessel abnormality that can cause serious symptoms such as seizures, intracerebral hemorrhage, and various neurological disorders. Manual detection of cavernomas by physicians in a large set of brain MRI slices is a time-consuming and labor-intensive task and often delays diagnosis. In this paper, we propose a computer-aided diagnosis (CAD) system for cavernomas based on T2-weighted axial plane MRI image analysis. The proposed technique first extracts the brain area based on atlas registration and active contour model, and then performs template matching to obtain candidate cavernoma regions. Texture, the histogram of oriented gradients and local binary pattern features of each candidate region are calculated, and principal component analysis is applied to reduce the feature dimensionality. Support vector machines (SVMs) are finally used to classify each region into cavernoma or non-cavernoma so that most of the false positives (obtained by template matching) are eliminated. The performance of the proposed CAD system is evaluated and experimental results show that it provides superior performance in cavernoma detection compared to existing techniques. Copyright © 2018 Elsevier Ltd. All rights reserved.

Automatic detection of muscle activity from mechanomyogram signals: a comparison of amplitude and wavelet-based methods.

PubMed

Alves, Natasha; Chau, Tom

2010-04-01

Knowledge of muscle activity timing is critical to many clinical applications, such as the assessment of muscle coordination and the prescription of muscle-activated switches for individuals with disabilities. In this study, we introduce a continuous wavelet transform (CWT) algorithm for the detection of muscle activity via mechanomyogram (MMG) signals. CWT coefficients of the MMG signal were compared to scale-specific thresholds derived from the baseline signal to estimate the timing of muscle activity. Test signals were recorded from the flexor carpi radialis muscles of 15 able-bodied participants as they squeezed and released a hand dynamometer. Using the dynamometer signal as a reference, the proposed CWT detection algorithm was compared against a global-threshold CWT detector as well as amplitude-based event detection for sensitivity and specificity to voluntary contractions. The scale-specific CWT-based algorithm exhibited superior detection performance over the other detectors. CWT detection also showed good muscle selectivity during hand movement, particularly when a given muscle was the primary facilitator of the contraction. This may suggest that, during contraction, the compound MMG signal has a recurring morphological pattern that is not prevalent in the baseline signal. The ability of CWT analysis to be implemented in real time makes it a candidate for muscle-activity detection in clinical applications.

Resist development status for immersion lithography

NASA Astrophysics Data System (ADS)

Tsuji, Hiromitsu; Yoshida, Masaaki; Ishizuka, Keita; Hirano, Tomoyuki; Endo, Kotaro; Sato, Mitsuru

2005-05-01

Immersion lithography has already demonstrated superior performance for next generation semiconductor manufacturing, while some challenges with contact immersion fluids and resist still remain. There are many interactions to be considered with regards to the solid and liquid interface. Resist elusion in particular requires very careful attention since the impact on the lens and fluid supply system in exposure tool could pose a significant risk at the manufacturing stage. TOK developed a screening procedure to detect resist elution of ion species down to ppb levels during non and post exposure steps. It was found that the PAG cation elution is affected by molecular weight and structure while the PAG anion elution was dependent on the molecular structure and mobility. In this paper, lithographic performance is also discussed with the low elution type resist.

High performance broadband photodetector based on MoS2/porous silicon heterojunction

NASA Astrophysics Data System (ADS)

Dhyani, Veerendra; Dwivedi, Priyanka; Dhanekar, Saakshi; Das, Samaresh

2017-11-01

A high speed efficient broadband photodetector based on a vertical n-MoS2/p-porous silicon heterostructure has been demonstrated. Large area MoS2 on electrochemical etched porous silicon was grown by sulphurization of a sputtered MoO3 thin film. A maximum responsivity of 9 A/W (550-850 nm) with a very high detectivity of ˜1014 Jones is observed. Transient measurements show a fast response time of ˜9 μs and is competent to work at high frequencies (˜50 kHz). The enhanced photodetection performance of the heterojunction made on porous silicon over that made on planar silicon is explained in terms of higher interfacial barrier height, superior light trapping property, and larger junction area in the MoS2/porous silicon junction.

On designing a new cumulative sum Wilcoxon signed rank chart for monitoring process location

PubMed Central

Nazir, Hafiz Zafar; Tahir, Muhammad; Riaz, Muhammad

2018-01-01

In this paper, ranked set sampling is used for developing a non-parametric location chart which is developed on the basis of Wilcoxon signed rank statistic. The average run length and some other characteristics of run length are used as the measures to assess the performance of the proposed scheme. Some selective distributions including Laplace (or double exponential), logistic, normal, contaminated normal and student’s t-distributions are considered to examine the performance of the proposed Wilcoxon signed rank control chart. It has been observed that the proposed scheme shows superior shift detection ability than some of the competing counterpart schemes covered in this study. Moreover, the proposed control chart is also implemented and illustrated with a real data set. PMID:29664919

A novel highly sensitive, rapid and safe Rift Valley fever virus neutralization test.

PubMed

Wichgers Schreur, Paul J; Paweska, Janusz T; Kant, Jet; Kortekaas, Jeroen

2017-10-01

Antibodies specific for Rift Valley fever virus (RVFV) can be detected by diverse methods, including ezyme-linked immunosortbent assay (ELISA) and virus neutralization test (VNT). The VNT is superior in sensitivity and specificity and is therefore considered the gold standard serological assay. Classical VNTs make use of virulent RVFV and therefore have to be performed in biosafety level 3 laboratories. Here, we report the development of a novel VNT that is based on an avirulent RVFV expressing the enhanced green fluorescent protein (eGFP), which can be performed safely outside level 3 biocontainment facilities. Evaluation with a broad panel of experimental sera and field sera demonstrated that this novel VNT is faster and more sensitive than the classical VNT. Copyright © 2017 Elsevier B.V. All rights reserved.

External laryngeal nerve in thyroid surgery: is the nerve stimulator necessary?

PubMed

Aina, E N; Hisham, A N

2001-09-01

To find out the incidence and type of external laryngeal nerves during operations on the thyroid, and to assess the role of a nerve stimulator in detecting them. Prospective, non-randomised study. Teaching hospital, Malaysia. 317 patients who had 447 dissections between early January 1998 and late November 1999. Number and type of nerves crossing the cricothyroid space, and the usefulness of the nerve stimulator in finding them. The nerve stimulator was used in 206/447 dissections (46%). 392 external laryngeal nerves were seen (88%), of which 196/206 (95%) were detected with the stimulator. However, without the stimulator 196 nerves were detected out of 241 dissections (81%). The stimulator detected 47 (23%) Type I nerves (nerve > 1 cm from the upper edge of superior pole); 86 (42%) Type IIa nerves (nerve < 1 cm from the upper edge of superior pole); and 63 (31%) Type IIb nerves (nerve below upper edge of superior pole). 10 nerves were not detected. When the stimulator was not used the corresponding figures were 32 (13%), 113 (47%), and 51 (21%), and 45 nerves were not seen. If the nerve cannot be found we recommend dissection of capsule close to the medial border of the upper pole of the thyroid to avoid injury to the nerve. Although the use of the nerve stimulator seems desirable, it confers no added advantage in finding the nerve. In the event of uncertainty about whether a structure is the nerve, the stimulator may help to confirm it. However, exposure of the cricothyroid space is most important for good exposure in searching for the external laryngeal nerve.

Multisensor configurations for early sniper detection

NASA Astrophysics Data System (ADS)

Lindgren, D.; Bank, D.; Carlsson, L.; Dulski, R.; Duval, Y.; Fournier, G.; Grasser, R.; Habberstad, H.; Jacquelard, C.; Kastek, M.; Otterlei, R.; Piau, G.-P.; Pierre, F.; Renhorn, I.; Sjöqvist, L.; Steinvall, O.; Trzaskawka, P.

2011-11-01

This contribution reports some of the fusion results from the EDA SNIPOD project, where different multisensor configurations for sniper detection and localization have been studied. A project aim has been to cover the whole time line from sniper transport and establishment to shot. To do so, different optical sensors with and without laser illumination have been tested, as well as acoustic arrays and solid state projectile radar. A sensor fusion node collects detections and background statistics from all sensors and employs hypothesis testing and multisensor estimation programs to produce unified and reliable sniper alarms and accurate sniper localizations. Operator interfaces that connect to the fusion node should be able to support both sniper countermeasures and the guidance of personnel to safety. Although the integrated platform has not been actually built, sensors have been evaluated at common field trials with military ammunitions in the caliber range 5.56 to 12.7 mm, and at sniper distances up to 900 m. It is concluded that integrating complementary sensors for pre- and postshot sniper detection in a common system with automatic detection and fusion will give superior performance, compared to stand alone sensors. A practical system is most likely designed with a cost effective subset of available complementary sensors.

A ROC-based feature selection method for computer-aided detection and diagnosis

NASA Astrophysics Data System (ADS)

Wang, Songyuan; Zhang, Guopeng; Liao, Qimei; Zhang, Junying; Jiao, Chun; Lu, Hongbing

2014-03-01

Image-based computer-aided detection and diagnosis (CAD) has been a very active research topic aiming to assist physicians to detect lesions and distinguish them from benign to malignant. However, the datasets fed into a classifier usually suffer from small number of samples, as well as significantly less samples available in one class (have a disease) than the other, resulting in the classifier's suboptimal performance. How to identifying the most characterizing features of the observed data for lesion detection is critical to improve the sensitivity and minimize false positives of a CAD system. In this study, we propose a novel feature selection method mR-FAST that combines the minimal-redundancymaximal relevance (mRMR) framework with a selection metric FAST (feature assessment by sliding thresholds) based on the area under a ROC curve (AUC) generated on optimal simple linear discriminants. With three feature datasets extracted from CAD systems for colon polyps and bladder cancer, we show that the space of candidate features selected by mR-FAST is more characterizing for lesion detection with higher AUC, enabling to find a compact subset of superior features at low cost.

The miniaturized Raman system and detection of traces of life in halite from the Atacama Desert: some considerations for the search for life signatures on Mars.

PubMed

Vítek, Petr; Jehlička, Jan; Edwards, Howell G M; Hutchinson, Ian; Ascaso, Carmen; Wierzchos, Jacek

2012-12-01

Raman spectroscopy is being adopted as a nondestructive instrumentation for the robotic exploration of Mars to search for traces of life in the geological record. Here, miniaturized Raman spectrometers of two different types equipped with 532 and 785 nm lasers for excitation, respectively, were compared for the detection of microbial biomarkers in natural halite from the hyperarid region of the Atacama Desert. Measurements were performed directly on the rock as well as on the homogenized, powdered samples prepared from this material-the effects of this sample preparation and the excitation wavelength employed in the analysis are compared and discussed. From these results, 532 nm excitation was found to be superior for the analysis of powdered specimens due to its high sensitivity toward carotenoids and hence a higher capability for their detection at relatively low concentration in bulk powdered specimens. For the same reason, this wavelength was a better choice for the detection of carotenoids in direct measurements made on the rock samples. The 785 nm excitation wavelength, in contrast, proved to be more sensitive toward the detection of scytonemin.

Detection of burst suppression patterns in EEG using recurrence rate.

PubMed

Liang, Zhenhu; Wang, Yinghua; Ren, Yongshao; Li, Duan; Voss, Logan; Sleigh, Jamie; Li, Xiaoli

2014-01-01

Burst suppression is a unique electroencephalogram (EEG) pattern commonly seen in cases of severely reduced brain activity such as overdose of general anesthesia. It is important to detect burst suppression reliably during the administration of anesthetic or sedative agents, especially for cerebral-protective treatments in various neurosurgical diseases. This study investigates recurrent plot (RP) analysis for the detection of the burst suppression pattern (BSP) in EEG. The RP analysis is applied to EEG data containing BSPs collected from 14 patients. Firstly we obtain the best selection of parameters for RP analysis. Then, the recurrence rate (RR), determinism (DET), and entropy (ENTR) are calculated. Then RR was selected as the best BSP index one-way analysis of variance (ANOVA) and multiple comparison tests. Finally, the performance of RR analysis is compared with spectral analysis, bispectral analysis, approximate entropy, and the nonlinear energy operator (NLEO). ANOVA and multiple comparison tests showed that the RR could detect BSP and that it was superior to other measures with the highest sensitivity of suppression detection (96.49%, P = 0.03). Tracking BSP patterns is essential for clinical monitoring in critically ill and anesthetized patients. The purposed RR may provide an effective burst suppression detector for developing new patient monitoring systems.

Enhancement of Localized Surface Plasmon Resonance polymer based biosensor chips using well-defined glycopolymers for lectin detection.

PubMed

Jin, Yan; Wong, Kok Hou; Granville, Anthony Michael

2016-01-15

Poly(methyl methacrylate) polymer based Localized Surface Plasmon Resonance biosensor chips were successfully fabricated using glycopolymer brushes carrying glucose moieties for the detection of concanavalin A. Poly(pentafluorostyrene), with pre-determined polymer chain lengths, were synthesized via a reversible addition-fragmentation chain transfer polymerization technique. The synthesized poly(pentafluorostyrene), was subsequently converted into glycopolymers via a para-fluoro-thiol "click" reaction and grafted onto the surface of sensor chips. The "glycocluster effect" induced by pendent carbohydrate moieties enabled a stronger affinity for concanavalin A binding, which resulted in a dramatic expansion of the sensors' response range. It was discovered that the longer polymer brushes did not guarantee additional enhancements for the sensor chips. Instead, they could lead to higher detection limits. In this study, the limit of detection for the sensor chips was discovered to be 1.3nmolL(-1) with a saturated response at 1054.2nmolL(-1). In addition to the superior performance, the capabilities of the reported sensor chips can be easily manipulated to detect a diverse range of analytes by "clicking" various sensing elements onto the polymer brushes. Copyright © 2015 Elsevier Inc. All rights reserved.

Teschoviruses as Indicators of Porcine Fecal Contamination of Surface Water

PubMed Central

Jiménez-Clavero, Miguel Angel; Fernández, Carlos; Ortiz, José Antonio; Pro, Javier; Carbonell, Gregoria; Tarazona, José Vicente; Roblas, Neftalí; Ley, Victoria

2003-01-01

Teschoviruses specifically infect pigs and are shed in pig feces. Hence, their presence in water should indicate contamination with pig fecal residues. To assess this hypothesis, we have developed a real-time reverse transcriptase PCR (RT-PCR) method that allows the quantitative detection of pig teschovirus (PTV) RNA. The method is able to detect 92 fg of PTV RNA per ml of sample. Using this method, we have detected the presence of PTV RNA in water and fecal samples from all pig farms examined (n = 5). Feces from other animal species (cattle, sheep, and goats) were negative in this test. To compare the PTV RNA detection method with conventional chemical determinations currently in use for evaluation of water contamination, we analyzed water samples collected downstream from a pig slurry spillage site. We have found a positive correlation within both types of determinations. The sensitivity of the PTV detection assay was similar to that achieved by unspecific organic matter determination and superior to all other conventional chemical analyses performed. Furthermore, the new method is highly specific, revealing the porcine origin of the contamination, a feature that is lacking in currently available methods for the assessment of water contamination. PMID:14532098

Performance and Characterization of a Modular Superconducting Nanowire Single Photon Detector System for Space-to-Earth Optical Communications Links

NASA Technical Reports Server (NTRS)

Vyhnalek, Brian E.; Tedder, Sarah A.; Nappier, Jennifer M.

2018-01-01

Space-to-ground photon-counting optical communication links supporting high data rates over large distances require enhanced ground receiver sensitivity in order to reduce the mass and power burden on the spacecraft transmitter. Superconducting nanowire single-photon detectors (SNSPDs) have been demonstrated to offer superior performance in detection efficiency, timing resolution, and count rates over semiconductor photodetectors, and are a suitable technology for high photon efficiency links. Recently photon detectors based on superconducting nanowires have become commercially available, and we have assessed the characteristics and performance of one such commercial system as a candidate for potential utilization in ground receiver designs. The SNSPD system features independent channels which can be added modularly, and we analyze the scalability of the system to support different data rates, as well as consider coupling concepts and issues as the number of channels increases.

DuPont Qualicon BAX System assay for genus Listeria 24E.

PubMed

Wallace, F Morgan; Fallon, Dawn; DeMarco, Daniel; Varkey, Stephen

2011-01-01

The new BAX System PCR Assay for Genus Listeria 24E was evaluated for detecting Listeria spp. in frankfurters, spinach, cooked shrimp, queso fresco cheese, and on stainless steel surfaces with a single-stage enrichment in BAX System 24 Listeria Enrichment Broth (24 LEB). Method comparison studies performed on samples with low-level inoculates showed that the BAX System demonstrates a sensitivity equivalent or superior to the U.S. Food and Drug Administration's Bacteriological Analytical Manual and the U.S. Department of Agriculture-Food Safety and Inspection Service culture methods, but with a significantly shorter time to result. Tests to evaluate inclusivity and exclusivity returned no false-negative and no false-positive results on a diverse panel of isolates, and tests for lot-to-lot variability and tablet stability demonstrated consistent performance. Ruggedness studies determined that none of the factors examined, within the range of deviations from specified parameters examined, affect the performance of the assay.

Detection of Cryptosporidium and Giardia in clinical laboratories in Europe--a comparative study.

PubMed

Manser, M; Granlund, M; Edwards, H; Saez, A; Petersen, E; Evengard, B; Chiodini, P

2014-01-01

To determine the routine diagnostic methods used and compare the performance in detection of oocysts of Cryptosporidium species and cysts of Giardia intestinalis in faecal samples by European specialist parasitology laboratories and European clinical laboratories. Two sets of seven formalin-preserved faecal samples, one containing cysts of Giardia intestinalis and the other, containing oocysts of Cryptosporidium, were sent to 18 laboratories. Participants were asked to examine the specimens using their routine protocol for detecting these parasites and state the method(s) used. Eighteen laboratories answered the questionnaire. For detection of Giardia, 16 of them used sedimentation/concentration followed by light microscopy. Using this technique the lower limit of detection of Giardia was 17.2 cysts/mL of faeces in the best performing laboratories. Only three of 16 laboratories used fluorescent-conjugated antibody-based microscopy. For detection of Cryptosporidium acid-fast staining was used by 14 of the 17 laboratories that examined the samples. With this technique the lower limit of detection was 976 oocysts/mL of faeces. Fluorescent-conjugated antibody-based microscopy was used by only five of the 17 laboratories. There was variation in the lower limit of detection of cysts of Giardia and oocysts of Cryptosporidium between laboratories using the same basic microscopic methods. Fluorescent-conjugated antibody-based microscopy was not superior to light microscopy under the conditions of this study. There is a need for a larger-scale multi-site comparison of the methods used for the diagnosis of these parasites and the development of a Europe-wide laboratory protocol based upon its findings. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

Improving the detection of evoked responses to periodic stimulation by using bivariate local spectral F-test - Application to EEG during photic stimulation.

PubMed

Felix, Leonardo Bonato; Rocha, Paulo Fábio; Mendes, Eduardo Mazoni Andrade Marçal; Miranda de Sá, Antonio Mauricio Ferreira Leite

2017-10-01

The spectral local F-test has been applied for detecting evoked responses to rhythmic stimulation that are embedded in the ongoing electroencephalogram (EEG). Based on the sampling distribution of a flat spectrum at the neighbourhood of the stimulation frequency, spectral peaks in an EEG signal that are due to the stimulation may be readily assessed. Nevertheless, the performance of the technique is strongly affected by both the signal-to-noise ratio (SNR) of the responses and the number of data segments used in the estimation. The present work aims at both deriving and evaluating a multivariate extension of local F-test by including the EEG collected at a second distinct derivation. The detection rate with this multivariate detector was found to be greater than that using a single channel in case of equal SNR in both signals. Monte Carlo simulation results showed that the probability of detection with this new detector saturates for signal-to-noise ratios above 12 dB and indicated a greater detection rate in practical situations, even when smaller SNR-values are found in the added signal (e.g. 5 dB for 16 neighbouring frequencies used in the estimation). The technique was next applied to the EEG from 12 subjects during intermittent, photic stimulation leading to superior performance in comparison with the univariate local F-test. Since a higher detection rate with the proposed technique is achieved without the need of increasing the number of data segments, it allows evoked responses to be detected faster, once the same detection rate may be accomplished with less segments. This might be useful in clinical practice. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

Bullets versus burgers: is it threat or relevance that captures attention?

PubMed

de Oca, Beatrice M; Black, Alison A

2013-01-01

Previous studies have found that potentially dangerous stimuli are better at capturing attention than neutral stimuli, a finding sometimes called the threat superiority effect. However, non-threatening stimuli also capture attention in many studies of visual attention. In Experiment 1, the relevance superiority effect was tested with a visual search task comparing detection times for threatening stimuli (guns), pleasant but motivationally relevant stimuli (food), and neutral stimuli (flowers and chairs). Gun targets were detected more rapidly than both types of neutral targets, whereas food targets were detected more quickly than the neutral chair targets only. Guns were detected more rapidly than food. In Experiment 2, threatening targets (guns and snakes), pleasant but motivationally relevant targets (money and food), and neutral targets (trees and couches) were all presented with the same neutral distractors (cactus and pots) in order to control for the valence of the distractor stimulus across the three categories of target stimuli. Threatening and pleasant target categories facilitated attention relative to neutral targets. The results support the view that both threatening and pleasant pictures can be detected more rapidly than neutral targets.

A Robust False Matching Points Detection Method for Remote Sensing Image Registration

NASA Astrophysics Data System (ADS)

Shan, X. J.; Tang, P.

2015-04-01

Given the influences of illumination, imaging angle, and geometric distortion, among others, false matching points still occur in all image registration algorithms. Therefore, false matching points detection is an important step in remote sensing image registration. Random Sample Consensus (RANSAC) is typically used to detect false matching points. However, RANSAC method cannot detect all false matching points in some remote sensing images. Therefore, a robust false matching points detection method based on Knearest- neighbour (K-NN) graph (KGD) is proposed in this method to obtain robust and high accuracy result. The KGD method starts with the construction of the K-NN graph in one image. K-NN graph can be first generated for each matching points and its K nearest matching points. Local transformation model for each matching point is then obtained by using its K nearest matching points. The error of each matching point is computed by using its transformation model. Last, L matching points with largest error are identified false matching points and removed. This process is iterative until all errors are smaller than the given threshold. In addition, KGD method can be used in combination with other methods, such as RANSAC. Several remote sensing images with different resolutions and terrains are used in the experiment. We evaluate the performance of KGD method, RANSAC + KGD method, RANSAC, and Graph Transformation Matching (GTM). The experimental results demonstrate the superior performance of the KGD and RANSAC + KGD methods.

Impact of frequency and polarization diversity on a terahertz radar's imaging performance

NASA Astrophysics Data System (ADS)

Cooper, Ken B.; Dengler, Robert J.; Llombart, Nuria

2011-05-01

The Jet Propulsion Laboratory's 675 GHz, 25 m standoff imaging radar can achieve >1 Hz real time frame rates over 40x40 cm fields of view for rapid detection of person-borne concealed weapons. In its normal mode of operation, the radar generates imagery based solely on the time-of-flight, or range, between the radar and target. With good clothing penetration at 675 GHz, a hidden object will be detectable as an anomaly in the range-to-surface profile of a subject. Here we report on results of two modifications in the radar system that were made to asses its performance using somewhat different detection approaches. First, the radar's operating frequency and bandwidth were cut in half, to 340 GHz and 13 GHz, where there potential system advantages include superior transmit power and clothing penetration, as well as a lower cost of components. In this case, we found that the twofold reduction in range and cross-range resolution sharply limited the quality of through-clothes imagery, although some improvement is observed for detection of large targets concealed by very thick clothing. The second radar modification tested involved operation in a fully polarimetric mode, where enhanced image contrast might occur between surfaces with different material or geometric characteristics. Results from these tests indicated that random speckle dominates polarimetric power imagery, making it an unattractive approach for contrast improvement. Taken together, the experiments described here underscore the primary importance of high resolution imaging in THz radar applications for concealed weapons detection.

A fast and high-sensitive dual-wavelength diffuse optical tomography system using digital lock-in photon-counting technique

NASA Astrophysics Data System (ADS)

Chen, Weiting; Yi, Xi; Zhao, Huijuan; Gao, Feng

2014-09-01

We presented a novel dual-wavelength diffuse optical imaging system which can perform 2-D or 3-D imaging fast and high-sensitively for monitoring the dynamic change of optical parameters. A newly proposed lock-in photon-counting detection method was adopted for week optical signal collection, which brought in excellent property as well as simplified geometry. Fundamental principles of the lock-in photon-counting detection were elaborately demonstrated, and the feasibility was strictly verified by the linearity experiment. Systemic performance of the prototype set up was experimentally accessed, including stray light rejection and inherent interference. Results showed that the system possessed superior anti-interference capability (under 0.58% in darkroom) compared with traditional photon-counting detection, and the crosstalk between two wavelengths was lower than 2.28%. For comprehensive assessment, 2-D phantom experiments towards relatively large dimension model (diameter of 4cm) were conducted. Different absorption targets were imaged to investigate detection sensitivity. Reconstruction image under all conditions was exciting, with a desirable SNR. Study on image quality v.s. integration time put forward a new method for accessing higher SNR with the sacrifice of measuring speed. In summary, the newly developed system showed great potential in promoting detection sensitivity as well as measuring speed. This will make substantial progress in dynamically tracking the blood concentration distribution in many clinical areas, such as small animal disease modeling, human brain activity research and thick tissues (for example, breast) diagnosis.

Comparison between capillary electrophoresis and high performance liquid chromatography for detection and quantification of Hb constant spring [Hb CS; α142, Term→Gln (TAA>CAA IN α2)].

PubMed

Waneesorn, Jarurin; Panyasai, Sitthichai; Kongthai, Kanyakan; Singboottra, Panthong; Pornprasert, Sakorn

2011-01-01

Hb Constant Spring [Hb CS; α142, Term→Gln (TAA>CAA in α2)] is often missed by routine laboratory testing since its mRNA as well as gene product are unstable and presented at a low level in peripheral blood. This study aimed to analyze the efficacy of capillary electrophoresis (CE) and high performance liquid chromatography (HPLC) for detecting and quantifying Hb CS in 19 heterozygotes and 14 homozygotes with Hb CS as well as 10 Hb H-CS disease subjects who were detected by molecular analysis. In the CE electrophoregram, Hb CS was seen at zone 2 and was observed in all samples, while the chromatogram of Hb CS peaks was found in 26.32% heterozygotes, 42.86% homozygotes and 90% Hb H-CS disease subjects, respectively. In addition, the Hb CS levels in each group of subjects quantified by CE were significantly higher than those quantified by HPLC. Based on the CE method, the lowest Hb CS level was found in the heterozygotes, whereas the highest level was found in the Hb H-CS disease patients. Therefore, the CE method was superior to the HPLC method for detecting Hb CS. Furthermore, the level of Hb CS quantified by CE proved useful in screening heterozygotes and homozygotes with Hb CS as well as Hb H-CS disease.

Neural Computation as a Tool to Differentiate Perceptual from Emotional Processes: The Case of Anger Superiority Effect

ERIC Educational Resources Information Center

Mermillod, Martial; Vermeulen, Nicolas; Lundqvist, Daniel; Niedenthal, Paula M.

2009-01-01

Research findings in social and cognitive psychology imply that it is easier to detect angry faces than happy faces in a crowd of neutral faces [Hansen, C. H., & Hansen, R. D. (1988). Finding the face in the crowd--An anger superiority effect. "Journal of Personality and Social Psychology," 54(6), 917-924]. This phenomenon has been held to have…

Fair lineups are better than biased lineups and showups, but not because they increase underlying discriminability.

PubMed

Smith, Andrew M; Wells, Gary L; Lindsay, R C L; Penrod, Steven D

2017-04-01

Receiver Operating Characteristic (ROC) analysis has recently come in vogue for assessing the underlying discriminability and the applied utility of lineup procedures. Two primary assumptions underlie recommendations that ROC analysis be used to assess the applied utility of lineup procedures: (a) ROC analysis of lineups measures underlying discriminability, and (b) the procedure that produces superior underlying discriminability produces superior applied utility. These same assumptions underlie a recently derived diagnostic-feature detection theory, a theory of discriminability, intended to explain recent patterns observed in ROC comparisons of lineups. We demonstrate, however, that these assumptions are incorrect when ROC analysis is applied to lineups. We also demonstrate that a structural phenomenon of lineups, differential filler siphoning, and not the psychological phenomenon of diagnostic-feature detection, explains why lineups are superior to showups and why fair lineups are superior to biased lineups. In the process of our proofs, we show that computational simulations have assumed, unrealistically, that all witnesses share exactly the same decision criteria. When criterial variance is included in computational models, differential filler siphoning emerges. The result proves dissociation between ROC curves and underlying discriminability: Higher ROC curves for lineups than for showups and for fair than for biased lineups despite no increase in underlying discriminability. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Tacit Knowledge Flows and Institutional Theory: Accelerating Acculturation

DTIC Science & Technology

2010-01-01

sustainable competitive advantage , but different kinds of knowledge affect competitive advantage differently. This applies especially to the...such qualitative fieldwork and informs theory and practice alike. 1. Introduction Knowledge is key to sustainable competitive advantage ...4,8,19]. Knowledge enables effective action; effective action drives superior performance; and superior performance supports competitive advantage

Monitoring of facial stress during space flight: Optical computer recognition combining discriminative and generative methods

NASA Astrophysics Data System (ADS)

Dinges, David F.; Venkataraman, Sundara; McGlinchey, Eleanor L.; Metaxas, Dimitris N.

2007-02-01

Astronauts are required to perform mission-critical tasks at a high level of functional capability throughout spaceflight. Stressors can compromise their ability to do so, making early objective detection of neurobehavioral problems in spaceflight a priority. Computer optical approaches offer a completely unobtrusive way to detect distress during critical operations in space flight. A methodology was developed and a study completed to determine whether optical computer recognition algorithms could be used to discriminate facial expressions during stress induced by performance demands. Stress recognition from a facial image sequence is a subject that has not received much attention although it is an important problem for many applications beyond space flight (security, human-computer interaction, etc.). This paper proposes a comprehensive method to detect stress from facial image sequences by using a model-based tracker. The image sequences were captured as subjects underwent a battery of psychological tests under high- and low-stress conditions. A cue integration-based tracking system accurately captured the rigid and non-rigid parameters of different parts of the face (eyebrows, lips). The labeled sequences were used to train the recognition system, which consisted of generative (hidden Markov model) and discriminative (support vector machine) parts that yield results superior to using either approach individually. The current optical algorithm methods performed at a 68% accuracy rate in an experimental study of 60 healthy adults undergoing periods of high-stress versus low-stress performance demands. Accuracy and practical feasibility of the technique is being improved further with automatic multi-resolution selection for the discretization of the mask, and automated face detection and mask initialization algorithms.

Plasma-free vs deconjugated metanephrines for diagnosis of phaeochromocytoma.

PubMed

Pamporaki, Christina; Därr, Roland; Bursztyn, Michael; Glöckner, Stephan; Bornstein, Stefan R; Lenders, Jacques W M; Pacak, Karel; Krinner, Axel; Eisenhofer, Graeme

2013-10-01

The diagnosis of phaeochromocytoma is commonly performed by the measurements of plasma-free normetanephrine and metanephrine. Plasma-deconjugated normetanephrine and metanephrine have been proposed as alternative, equivalent, but easier to measure biomarkers. The aim of this study was to compare the diagnostic performance of plasma-free vs deconjugated normetanephrine and metanephrine in patients tested for phaeochromocytoma. The study population included a reference group of 262 normotensive and hypertensive volunteers, 198 patients with phaeochromocytoma and 528 patients initially suspected of having the tumour, but with negative investigations after at least 2 years of follow-up. Measurements were performed using liquid chromatography with electrochemical detection. Plasma concentrations of free normetanephrine were 17-fold higher in patients with phaeochromocytoma than in the reference population, a 72% larger (P < 0·001) difference than that for the 10-fold higher levels of plasma-deconjugated normetanephrine. In contrast, relative increases in plasma concentrations of free and deconjugated metanephrine were similar. Using upper cut-offs established in the reference population, measurements of plasma-free metabolites provided superior diagnostic performance than deconjugated metabolites according to measures of both sensitivity (97% vs 92%, P = 0·002) and specificity (93% vs 89%, P = 0·012). The area under the receiver operating characteristic curve for the free metabolites was larger than that for the deconjugated metabolites (0·986 vs 0·965, P < 0·001). Measurements of plasma-free normetanephrine and metanephrine are superior to the deconjugated metabolites for diagnosis of phaeochromocytoma. © 2013 John Wiley & Sons Ltd.

Do Superior or Inferior Interlaminar Approach or Bevel Orientation Predispose to Nonepidural Needle Penetration?

PubMed

Koontz, Nicholas A; Wiggins, Richard H; Stoddard, Gregory J; Shah, Lubdha M

2017-10-01

There is a paucity of evidence-based literature regarding the advantages and disadvantages of the interlaminar approach and needle bevel orientation for performing a lumbar interlaminar epidural steroid injection (ESI). The purpose of this study was to determine if superior versus inferior lamina approach, needle bevel tip orientation, or both may predispose to inadvertent nonepidural penetration during lumbar interlaminar ESI. A prospective study was performed of patients with low back pain with or without radicular pain or neurogenic claudication referred for lumbar interlaminar ESI. Two hundred eleven patients were randomized by interlaminar approach (superior vs inferior) and bevel tip orientation (cranial vs caudal). Lumbar interlaminar ESI was performed by six interventionalists of varying levels of experience using fluoroscopic guidance with curved tip epidural needles, using loss-of-resistance technique and confirmation with contrast opacification. Exact Poisson regression was used to model the study outcome. Two hundred twenty-one lumbar interlaminar ESIs were performed on 211 patients, randomized to a superior (n = 121) or inferior lamina approach (n = 100) and to a cranial (n = 103) or caudal (n = 118) orientation of the bevel tip. Epidural needle placement was confirmed in 96.4% (n = 213) of cases. Nonepidural needle placement was most commonly associated with superior lamina approach and caudal bevel tip orientation, which was marginally significant (adjusted risk ratio, 6.88; 95% CI, 0.93-∞; p = 0.059). Inadvertent nonepidural needle penetration during fluoroscopically guided lumbar interlaminar ESI appears to be affected by approach, with superior lamina approach and caudal bevel tip orientation being the least favorable technique.

Discrimination of Breast Cancer with Microcalcifications on Mammography by Deep Learning.

PubMed

Wang, Jinhua; Yang, Xi; Cai, Hongmin; Tan, Wanchang; Jin, Cangzheng; Li, Li

2016-06-07

Microcalcification is an effective indicator of early breast cancer. To improve the diagnostic accuracy of microcalcifications, this study evaluates the performance of deep learning-based models on large datasets for its discrimination. A semi-automated segmentation method was used to characterize all microcalcifications. A discrimination classifier model was constructed to assess the accuracies of microcalcifications and breast masses, either in isolation or combination, for classifying breast lesions. Performances were compared to benchmark models. Our deep learning model achieved a discriminative accuracy of 87.3% if microcalcifications were characterized alone, compared to 85.8% with a support vector machine. The accuracies were 61.3% for both methods with masses alone and improved to 89.7% and 85.8% after the combined analysis with microcalcifications. Image segmentation with our deep learning model yielded 15, 26 and 41 features for the three scenarios, respectively. Overall, deep learning based on large datasets was superior to standard methods for the discrimination of microcalcifications. Accuracy was increased by adopting a combinatorial approach to detect microcalcifications and masses simultaneously. This may have clinical value for early detection and treatment of breast cancer.

Knee Joint Vibration Signal Analysis with Matching Pursuit Decomposition and Dynamic Weighted Classifier Fusion

PubMed Central

Cai, Suxian; Yang, Shanshan; Zheng, Fang; Lu, Meng; Wu, Yunfeng; Krishnan, Sridhar

2013-01-01

Analysis of knee joint vibration (VAG) signals can provide quantitative indices for detection of knee joint pathology at an early stage. In addition to the statistical features developed in the related previous studies, we extracted two separable features, that is, the number of atoms derived from the wavelet matching pursuit decomposition and the number of significant signal turns detected with the fixed threshold in the time domain. To perform a better classification over the data set of 89 VAG signals, we applied a novel classifier fusion system based on the dynamic weighted fusion (DWF) method to ameliorate the classification performance. For comparison, a single leastsquares support vector machine (LS-SVM) and the Bagging ensemble were used for the classification task as well. The results in terms of overall accuracy in percentage and area under the receiver operating characteristic curve obtained with the DWF-based classifier fusion method reached 88.76% and 0.9515, respectively, which demonstrated the effectiveness and superiority of the DWF method with two distinct features for the VAG signal analysis. PMID:23573175

Discrimination of Breast Cancer with Microcalcifications on Mammography by Deep Learning

PubMed Central

Wang, Jinhua; Yang, Xi; Cai, Hongmin; Tan, Wanchang; Jin, Cangzheng; Li, Li

2016-01-01

Microcalcification is an effective indicator of early breast cancer. To improve the diagnostic accuracy of microcalcifications, this study evaluates the performance of deep learning-based models on large datasets for its discrimination. A semi-automated segmentation method was used to characterize all microcalcifications. A discrimination classifier model was constructed to assess the accuracies of microcalcifications and breast masses, either in isolation or combination, for classifying breast lesions. Performances were compared to benchmark models. Our deep learning model achieved a discriminative accuracy of 87.3% if microcalcifications were characterized alone, compared to 85.8% with a support vector machine. The accuracies were 61.3% for both methods with masses alone and improved to 89.7% and 85.8% after the combined analysis with microcalcifications. Image segmentation with our deep learning model yielded 15, 26 and 41 features for the three scenarios, respectively. Overall, deep learning based on large datasets was superior to standard methods for the discrimination of microcalcifications. Accuracy was increased by adopting a combinatorial approach to detect microcalcifications and masses simultaneously. This may have clinical value for early detection and treatment of breast cancer. PMID:27273294

Infrared-enhanced TV for fire detection

NASA Technical Reports Server (NTRS)

Hall, J. R.

1978-01-01

Closed-circuit television is superior to conventional smoke or heat sensors for detecting fires in large open spaces. Single TV camera scans entire area, whereas many conventional sensors and maze of interconnecting wiring might be required to get same coverage. Camera is monitored by person who would trip alarm if fire were detected, or electronic circuitry could process camera signal for fully-automatic alarm system.

Direct fluorescent antibody technique for the detection of bacterial kidney disease in paraffin-embedded tissues

USGS Publications Warehouse

Ochiai, T.; Yasutake, W.T.; Gould, R.W.

1985-01-01

The direct fluorescent antibody technique (FAT) was successfully used to detect the causative agent of bacterial kidney disease (BKD), Renibacterium salmoninarum, in Bouin's solution flexed and paraffinembedded egg and tissue sections. This method is superior to gram stain and may be particularly useful in detecting the BKD organism in fish with low-grade infection.

Graphene based strain sensor with LCP substrate

NASA Astrophysics Data System (ADS)

Nie, M.; Yang, H. S.; Xia, Y. H.

2018-02-01

A flexible strain sensor constructed by an efficient, low-cost fabrication strategy is presented in this paper. It is assembled by adhering grid-like graphene on LCP substrate. Kinds of measurement setup have been designed to verify that the proposed flexible sensor device is suitable to be used in health monitoring system. From the experiment results, it can be proved that the sensor exhibits the following features: ultra-light, relatively good sensitivity, high reversibility, superior physical robustness, easy fabrication. With the great performance of this flexible strain sensor, it is considered to play an important role in body monitoring, structural health monitoring system, fatigue detection and healthcare systems in the near future.

Severe Obstructive Calcification of the Descending Aorta: A Case Report of "Coral Reef Aorta".

PubMed

Ishigaki, Takahiro; Matsuda, Hitoshi; Henmi, Soichiro; Yoshida, Masato; Mukohara, Nobuhiko

2017-06-25

An 82-year-old man suffering from lower back pain and dyspnea presented to our institute in a state of shock. Computed tomography showed subtotal occlusion of the descending aorta with massive atherosclerotic calcification. As the proximal portion of the superior mesenteric artery was obstructed, emergency bypass from the right axillary artery to the bilateral external iliac arteries was performed, but the patient died 2 days later. Autopsy revealed that reddish-brown and verrucous masses obstructed the descending aorta, and high-grade thickening of the intima and extensive deposits of calcium in the lumina and medial layer were detected in the descending aorta histologically.

Synthesis of functional carbon nanospheres by a composite-molten-salt method and amperometric sensing of hydrogen peroxide.

PubMed

Wang, Xue; Hu, Chenguo; Xiong, Yufeng; Zhang, Cuiling

2013-02-01

Functional carbon nanospheres have been synthesized from analytically pure glucose by a composite-molten-salt (CMS) method. Field emission scanning electron microscopy, transmission electron microscopy, Raman and Fourier transformation infra-red spectroscopy indicate the carbon nanospheres are solid, bond hybridisation (sp2/sp3) and with many functional groups on their surfaces. Amperometric sensor based on the synthesized carbon nanospheres have been fabricated without pretreatment or modification. The detection of hydrogen peroxide exhibits high sensitivity and good selectivity. The electrochemical measurement of these nanospheres demonstrates much superior performance to those of the carbon nanospheres synthesized by hydrothermal method.

Multiparametric Magnetic Resonance Imaging (MRI) and MRI-Transrectal Ultrasound Fusion Biopsy for Index Tumor Detection: Correlation with Radical Prostatectomy Specimen.

PubMed

Radtke, Jan P; Schwab, Constantin; Wolf, Maya B; Freitag, Martin T; Alt, Celine D; Kesch, Claudia; Popeneciu, Ionel V; Huettenbrink, Clemens; Gasch, Claudia; Klein, Tilman; Bonekamp, David; Duensing, Stefan; Roth, Wilfried; Schueler, Svenja; Stock, Christian; Schlemmer, Heinz-Peter; Roethke, Matthias; Hohenfellner, Markus; Hadaschik, Boris A

2016-11-01

Multiparametric magnetic resonance imaging (mpMRI) and MRI fusion targeted biopsy (FTB) detect significant prostate cancer (sPCa) more accurately than conventional biopsies alone. To evaluate the detection accuracy of mpMRI and FTB on radical prostatectomy (RP) specimen. From a cohort of 755 men who underwent transperineal MRI and transrectal ultrasound fusion biopsy under general anesthesia between 2012 and 2014, we retrospectively analyzed 120 consecutive patients who had subsequent RP. All received saturation biopsy (SB) in addition to FTB of lesions with Prostate Imaging Reporting and Data System (PI-RADS) score ≥2. The index lesion was defined as the lesion with extraprostatic extension, the highest Gleason score (GS), or the largest tumor volume (TV) if GS were the same, in order of priority. GS 3+3 and TV ≥1.3ml or GS ≥3+4 and TV ≥0.55ml were considered sPCa. We assessed the detection accuracy by mpMRI and different biopsy approaches and analyzed lesion agreement between mpMRI and RP specimen. Overall, 120 index and 71 nonindex lesions were detected. Overall, 107 (89%) index and 51 (72%) nonindex lesions harbored sPCa. MpMRI detected 110 of 120 (92%) index lesions, FTB (two cores per lesion) alone diagnosed 96 of 120 (80%) index lesions, and SB alone diagnosed 110 of 120 (92%) index lesions. Combined SB and FTB detected 115 of 120 (96%) index foci. FTB performed significantly less accurately compared with mpMRI (p=0.02) and the combination for index lesion detection (p=0.002). Combined FTB and SB detected 97% of all sPCa lesions and was superior to mpMRI (85%), FTB (79%), and SB (88%) alone (p<0.001 each). Spearman's rank correlation coefficient for index lesion agreement between mpMRI and RP was 0.87 (p<0.001). Limitations included the retrospective design, multiple operators, and nonblinding of radiologists. MpMRI identified 92% of index lesions compared with RP histopathology. The combination of FTB and SB was superior to both approaches alone, reliably detecting 97% of sPCa lesions. Multiparametric magnetic resonance imaging detects the index lesion accurately in 9 of 10 patients; however, the combined biopsy approach, while missing less significant cancer, comes at the cost of detecting more insignificant cancer. Copyright © 2016 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Spectral imaging of chemical compounds using multivariate optically enhanced filters integrated with InGaAs VGA cameras

NASA Astrophysics Data System (ADS)

Priore, Ryan J.; Jacksen, Niels

2016-05-01

Infrared hyperspectral imagers (HSI) have been fielded for the detection of hazardous chemical and biological compounds, tag detection (friend versus foe detection) and other defense critical sensing missions over the last two decades. Low Size/Weight/Power/Cost (SWaPc) methods of identification of chemical compounds spectroscopy has been a long term goal for hand held applications. We describe a new HSI concept for low cost / high performance InGaAs SWIR camera chemical identification for military, security, industrial and commercial end user applications. Multivariate Optical Elements (MOEs) are thin-film devices that encode a broadband, spectroscopic pattern allowing a simple broadband detector to generate a highly sensitive and specific detection for a target analyte. MOEs can be matched 1:1 to a discrete analyte or class prediction. Additionally, MOE filter sets are capable of sensing an orthogonal projection of the original sparse spectroscopic space enabling a small set of MOEs to discriminate a multitude of target analytes. This paper identifies algorithms and broadband optical filter designs that have been demonstrated to identify chemical compounds using high performance InGaAs VGA detectors. It shows how some of the initial models have been reduced to simple spectral designs and tested to produce positive identification of such chemicals. We also are developing pixilated MOE compressed detection sensors for the detection of a multitude of chemical targets in challenging backgrounds/environments for both commercial and defense/security applications. This MOE based, real-time HSI sensor will exhibit superior sensitivity and specificity as compared to currently fielded HSI systems.

CRISPR Recognition Tool (CRT): a tool for automatic detection ofclustered regularly interspaced palindromic repeats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bland, Charles; Ramsey, Teresa L.; Sabree, Fareedah

Clustered Regularly Interspaced Palindromic Repeats (CRISPRs) are a novel type of direct repeat found in a wide range of bacteria and archaea. CRISPRs are beginning to attract attention because of their proposed mechanism; that is, defending their hosts against invading extrachromosomal elements such as viruses. Existing repeat detection tools do a poor job of identifying CRISPRs due to the presence of unique spacer sequences separating the repeats. In this study, a new tool, CRT, is introduced that rapidly and accurately identifies CRISPRs in large DNA strings, such as genomes and metagenomes. CRT was compared to CRISPR detection tools, Patscan andmore » Pilercr. In terms of correctness, CRT was shown to be very reliable, demonstrating significant improvements over Patscan for measures precision, recall and quality. When compared to Pilercr, CRT showed improved performance for recall and quality. In terms of speed, CRT also demonstrated superior performance, especially for genomes containing large numbers of repeats. In this paper a new tool was introduced for the automatic detection of CRISPR elements. This tool, CRT, was shown to be a significant improvement over the current techniques for CRISPR identification. CRT's approach to detecting repetitive sequences is straightforward. It uses a simple sequential scan of a DNA sequence and detects repeats directly without any major conversion or preprocessing of the input. This leads to a program that is easy to describe and understand; yet it is very accurate, fast and memory efficient, being O(n) in space and O(nm/l) in time.« less

Improved LabPET Detectors Using Lu1.8Gd0.2SiO5:Ce (LGSO) Scintillator Blocks

NASA Astrophysics Data System (ADS)

Bergeron, Mélanie; Pepin, Catherine M.; Cadorette, Jules; Loignon-Houle, Francis; Fontaine, Réjean; Lecomte, Roger

2015-02-01

The scintillator is one of the key building blocks that critically determine the physical performance of PET detectors. The quest for scintillation crystals with improved characteristics has been crucial in designing scanners with superior imaging performance. Recently, it was shown that the decay time constant of high lutetium content Lu1.8Gd0.2SiO5: Ce (LGSO) scintillators can be adjusted by varying the cerium concentration from 0.025 mol% to 0.75 mol%, thus providing interesting characteristics for phoswich detectors. The high light output (90%-120% NaI) and the improved spectral match of these scintillators with avalanche photodiode (APD) readout promise superior energy and timing resolutions. Moreover, their improved mechanical properties, as compared to conventional LGSO ( Lu0.4Gd1.6SiO5: Ce), make block array manufacturing readily feasible. To verify these assumptions, new phoswich block arrays made of LGSO-90%Lu with low and high mol% Ce concentrations were fabricated and assembled into modules dedicated to the LabPET scanner. Typical crystal decay time constants were 31 ns and 47 ns, respectively. Phoswich crystal identification performed using a digital pulse shape discrimination algorithm yielded an average 8% error. At 511 keV, an energy resolution of 17-21% was obtained, while coincidence timing resolution between 4.6 ns and 5.2 ns was achieved. The characteristics of this new LGSO-based phoswich detector module are expected to improve the LabPET scanner performance. The higher stopping power would increase the detection efficiency. The better timing resolution would also allow the use of a narrower coincidence window, thus minimizing the random event rate. Altogether, these two improvements will significantly enhance the noise equivalent count rate performance of an all LGSO-based LabPET scanner.

Dynamic Kinetic Resolution Enabled by Intramolecular Benzoin Reaction: Synthetic Applications and Mechanistic Insights.

PubMed

Zhang, Guoxiang; Yang, Shuang; Zhang, Xiaoyan; Lin, Qiqiao; Das, Deb K; Liu, Jian; Fang, Xinqiang

2016-06-29

The highly enantio-, diastereo-, and regioselective dynamic kinetic resolution of β-ketoesters and 1,3-diketones was achieved via a chiral N-heterocyclic carbene catalyzed intramolecular cross-benzoin reaction. A variety of tetralone derivatives bearing two contiguous stereocenters and multiple functionalities were liberated in moderate to excellent yields and with high levels of stereoselectivity (>95% ee and >20:1 dr in most cases). In addition, the excellent regioselectivity control for aryl/alkyl 1,3-diketones, and the superior electronic differentiation of 1,3-diarylketones were highlighted. Moreover, a set of new mechanistic rationale that differs with the currently widely accepted understanding of intramolecular benzoin reactions was established to demonstrate the superior preference of benzoin over aldol transformation: (1) A coexistence of competitive aldol and benzoin reactions was detected, but a retro-aldol-irreversible benzoin process performs a vital role in the generation of predominant benzoin products. (2) The most essential role of an N-electron-withdrawing substituent in triazolium catalysts was revealed to be accelerating the rate of the benzoin transformation, rather than suppressing the aldol process through reducing the inherent basicity of the catalyst.

A novel semi-transductive learning framework for efficient atypicality detection in chest radiographs

NASA Astrophysics Data System (ADS)

Alzubaidi, Mohammad; Balasubramanian, Vineeth; Patel, Ameet; Panchanathan, Sethuraman; Black, John A., Jr.

2012-03-01

Inductive learning refers to machine learning algorithms that learn a model from a set of training data instances. Any test instance is then classified by comparing it to the learned model. When the set of training instances lend themselves well to modeling, the use of a model substantially reduces the computation cost of classification. However, some training data sets are complex, and do not lend themselves well to modeling. Transductive learning refers to machine learning algorithms that classify test instances by comparing them to all of the training instances, without creating an explicit model. This can produce better classification performance, but at a much higher computational cost. Medical images vary greatly across human populations, constituting a data set that does not lend itself well to modeling. Our previous work showed that the wide variations seen across training sets of "normal" chest radiographs make it difficult to successfully classify test radiographs with an inductive (modeling) approach, and that a transductive approach leads to much better performance in detecting atypical regions. The problem with the transductive approach is its high computational cost. This paper develops and demonstrates a novel semi-transductive framework that can address the unique challenges of atypicality detection in chest radiographs. The proposed framework combines the superior performance of transductive methods with the reduced computational cost of inductive methods. Our results show that the proposed semitransductive approach provides both effective and efficient detection of atypical regions within a set of chest radiographs previously labeled by Mayo Clinic expert thoracic radiologists.

Attention-level transitory response: a novel hybrid BCI approach

NASA Astrophysics Data System (ADS)

Diez, Pablo F.; Garcés Correa, Agustina; Orosco, Lorena; Laciar, Eric; Mut, Vicente

2015-10-01

Objective. People with disabilities may control devices such as a computer or a wheelchair by means of a brain-computer interface (BCI). BCI based on steady-state visual evoked potentials (SSVEP) requires visual stimulation of the user. However, this SSVEP-based BCI suffers from the ‘Midas touch effect’, i.e., the BCI can detect an SSVEP even when the user is not gazing at the stimulus. Then, these incorrect detections deteriorate the performance of the system, especially in asynchronous BCI because ongoing EEG is classified. In this paper, a novel transitory response of the attention-level of the user is reported. It was used to develop a hybrid BCI (hBCI). Approach. Three methods are proposed to detect the attention-level of the user. They are based on the alpha rhythm and theta/beta rate. The proposed hBCI scheme is presented along with these methods. Hence, the hBCI sends a command only when the user is at a high-level of attention, or in other words, when the user is really focused on the task being performed. The hBCI was tested over two different EEG datasets. Main results. The performance of the hybrid approach is superior to the standard one. Improvements of 20% in accuracy and 10 bits min-1 are reported. Moreover, the attention-level is extracted from the same EEG channels used in SSVEP detection and this way, no extra hardware is needed. Significance. A transitory response of EEG signal is used to develop the attention-SSVEP hBCI which is capable of reducing the Midas touch effect.

Attention-level transitory response: a novel hybrid BCI approach.

PubMed

Diez, Pablo F; Garcés Correa, Agustina; Orosco, Lorena; Laciar, Eric; Mut, Vicente

2015-10-01

People with disabilities may control devices such as a computer or a wheelchair by means of a brain-computer interface (BCI). BCI based on steady-state visual evoked potentials (SSVEP) requires visual stimulation of the user. However, this SSVEP-based BCI suffers from the 'Midas touch effect', i.e., the BCI can detect an SSVEP even when the user is not gazing at the stimulus. Then, these incorrect detections deteriorate the performance of the system, especially in asynchronous BCI because ongoing EEG is classified. In this paper, a novel transitory response of the attention-level of the user is reported. It was used to develop a hybrid BCI (hBCI). Three methods are proposed to detect the attention-level of the user. They are based on the alpha rhythm and theta/beta rate. The proposed hBCI scheme is presented along with these methods. Hence, the hBCI sends a command only when the user is at a high-level of attention, or in other words, when the user is really focused on the task being performed. The hBCI was tested over two different EEG datasets. The performance of the hybrid approach is superior to the standard one. Improvements of 20% in accuracy and 10 bits min(-1) are reported. Moreover, the attention-level is extracted from the same EEG channels used in SSVEP detection and this way, no extra hardware is needed. A transitory response of EEG signal is used to develop the attention-SSVEP hBCI which is capable of reducing the Midas touch effect.

Progress in the development of immunoanalytical methods incorporating recombinant antibodies to small molecular weight biotoxins.

PubMed

Kavanagh, Owen; Elliott, Christopher T; Campbell, Katrina

2015-04-01

Rapid immunoanalytical screening of food and environmental samples for small molecular weight (hapten) biotoxin contaminations requires the production of antibody reagents that possess the requisite sensitivity and specificity. To date animal-derived polyclonal (pAb) and monoclonal (mAb) antibodies have provided the binding element of the majority of these assays but recombinant antibodies (rAb) isolated from in vitro combinatorial phage display libraries are an exciting alternative due to (1) circumventing the need for experimental animals, (2) speed of production in commonly used in vitro expression systems and (3) subsequent molecular enhancement of binder performance. Short chain variable fragments (scFv) have been the most commonly employed rAb reagents for hapten biotoxin detection over the last two decades but antibody binding fragments (Fab) and single domain antibodies (sdAb) are increasing in popularity due to increased expression efficiency of functional binders and superior resistance to solvents. rAb-based immunochromatographic assays and surface plasmon resonance (SPR) biosensors have been reported to detect sub-regulatory levels of fungal (mycotoxins), marine (phycotoxins) and aquatic biotoxins in a wide range of food and environmental matrices, however this technology has yet to surpass the performances of the equivalent mAb- and pAb-based formats. As such the full potential of rAb technology in hapten biotoxin detection has yet to be achieved, but in time the inherent advantages of engineered rAb are set to provide the next generation of ultra-high performing binder reagents for the rapid and specific detection of hapten biotoxins.

Options in human papillomavirus (HPV) detection for cervical cancer screening: comparison between full genotyping and a rapid qualitative HPV-DNA assay in Ghana.

PubMed

Obiri-Yeboah, Dorcas; Adu-Sarkodie, Yaw; Djigma, Florencia; Akakpo, Kafui; Aniakwa-Bonsu, Ebenezer; Amoako-Sakyi, Daniel; Jacques, Simpore; Mayaud, Philippe

2017-01-01

Modern cervical cancer screening increasingly relies on the use of molecular techniques detecting high-risk oncogenic human papillomavirus (hr-HPV). A major challenge for developing countries like Ghana has been the unavailability and costs of HPV DNA-based testing. This study compares the performance of care HPV, a semi-rapid and affordable qualitative detection assay for 14 hr-HPV genotypes, with HPV genotyping, for the detection of cytological cervical squamous intraepithelial lesions (SIL). A study comparing between frequency matched HIV-1 seropositive and HIV-seronegative women was conducted in the Cape Coast Teaching Hospital, Ghana. A systematic sampling method was used to select women attending clinics in the hospital. Cervical samples were tested for HPV by care HPV and Anyplex-II HPV28 genotyping assay, and by conventional cytology. A total of 175 paired results (94 from HIV-1 seropositive and 81 from HIV-seronegative women) were analyzed based on the ability of both tests to detect the 14 hr-HPV types included in the care HPV assay. The inter-assay concordance was 94.3% (95%CI: 89.7-97.2%, kappa = 0.88), similar by HIV serostatus. The care HPV assay was equally sensitive among HIV-1 seropositive and seronegative women (97.3% vs. 95.7%, p  = 0.50) and slightly more specific among HIV-seronegative women (85.0% vs. 93.1%, p  = 0.10). care HPV had good sensitivity (87.5%) but low specificity (52.1%) for the detection of low SIL or greater lesions, but its performance was superior to genotyping (87.5 and 38.8%, respectively). Reproducibility of care HPV, tested on 97 samples by the same individual was 82.5% (95%CI: 73.4-89.4%). The performance characteristics of care HPV compared to genotyping suggest that this simpler and cheaper HPV detection assay could offer a suitable alternative for HPV screening in Ghana.

Imaging of Pericardiophrenic Bundles Using Multislice Spiral Computed Tomography for Phrenic Nerve Anatomy.

PubMed

Wang, Yan-Jing; Liu, Lin; Zhang, Meng-Chao; Sun, Huan; Zeng, Hong; Yang, Ping

2016-08-01

Phrenic nerve injury and diaphragmatic stimulation are common complications following arrhythmia ablation and pacing therapies. Preoperative comprehension of phrenic nerve anatomy via non-invasive CT imaging may help to minimize the electrophysiological procedure-related complications. Coronary CT angiography data of 121 consecutive patients were collected. Imaging of left and right pericardiophrenic bundles was performed with volume rendering and multi-planar reformation techniques. The shortest spatial distances between phrenic nerves and key electrophysiology-related structures were determined. The frequencies of the shortest distances ≤5 mm, >5 mm and direct contact between phrenic nerves and adjacent structures were calculated. Left and right pericardiophrenic bundles were identified in 86.8% and 51.2% of the patients, respectively. The right phrenic nerve was <5 mm from right superior and inferior pulmonary veins in 92.0% and 3.2% of the patients, respectively. The percentage of right phrenic nerve, <5 mm from right atrium, superior caval vein, and superior caval vein-right atrium junction was 87.1%, 100%, and 62.9%, respectively. Left phrenic nerve was <5 mm from left atrial appendage, great cardiac vein, anterior and posterior interventricular veins, and left ventricular posterior veins in 81.9%, 1.0%, 39.1%, 28.6%, and 91.4% of the patients, respectively. Merely 0.06% left phrenic nerve had a distance <5 mm with left superior pulmonary vein, and none left phrenic nerve showed a distance <5 mm with left inferior pulmonary vein. One-stop enhanced CT scanning enabled detection of phrenic nerve anatomy, which might facilitate avoidance of the phrenic nerve-related complications in interventional electrophysiology. © 2016 Wiley Periodicals, Inc.

Dual mini-fragment plating for midshaft clavicle fractures: a clinical and biomechanical investigation.

PubMed

Prasarn, Mark L; Meyers, Kathleen N; Wilkin, Geoffrey; Wellman, David S; Chan, Daniel B; Ahn, Jaimo; Lorich, Dean G; Helfet, David L

2015-12-01

We sought to evaluate clinical and biomechanical outcomes of dual mini-fragment plate fixation for clavicle fractures. We hypothesized that this technique would produce an anatomical reduction with good clinical outcomes, be well tolerated by patients, and demonstrate equivalent biomechanics to single plating. Dual mini-fragment plating was performed for 17 isolated, displaced midshaft clavicle fractures. Functional outcomes and complications were retrospectively reviewed. A sawbones model compared dual plating biomechanics to a (1) superior 3.5-mm locking reconstruction plate, or (2) antero-inferior 3.5-mm locking reconstruction plate. On biomechanical testing, with anterior loading, dual plating was significantly more rigid than single locked anterior-plating (p = 0.02) but less rigid than single locked superior-plating (p = 0.001). With superior loading, dual plating trended toward higher rigidity versus single locked superior-plating (p = 0.07) but was less rigid than single locked anterior-plating (p = 0.03). No statistically significant differences in axial loading (p = 0.27) or torsion (p = 0.23) were detected. Average patient follow-up was 16.1 months (12-38). Anatomic reduction was achieved and maintained through final healing (average 14.7 weeks). No patient underwent hardware removal. Average 1-year DASH score was 4.0 (completed in 88 %). Displaced midshaft clavicle fractures can be effectively managed with dual mini-fragment plating. This technique results in high union rates and excellent clinical outcomes. Compared to single plating, dual plating is biomechanically equivalent in axial loading and torsion, yet offers better multi-planar bending stiffness despite the use of smaller plates. This technique may decrease the need for secondary surgery due to implant prominence and may aid in fracture reduction by buttressing butterfly fragments in two planes.

SU-D-204-05: Quantitative Comparison of a High Resolution Micro-Angiographic Fluoroscopic (MAF) Detector with a Standard Flat Panel Detector (FPD) Using the New Metric of Generalized Measured Relative Object Detectability (GM-ROD)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Russ, M; Ionita, C; Bednarek, D

Purpose: In endovascular image-guided neuro-interventions, visualization of fine detail is paramount. For example, the ability of the interventionist to visualize the stent struts depends heavily on the x-ray imaging detector performance. Methods: A study to examine the relative performance of the high resolution MAF-CMOS (pixel size 75µm, Nyquist frequency 6.6 cycles/mm) and a standard Flat Panel Detector (pixel size 194µm, Nyquist frequency 2.5 cycles/mm) detectors in imaging a neuro stent was done using the Generalized Measured Relative Object Detectability (GM-ROD) metric. Low quantum noise images of a deployed stent were obtained by averaging 95 frames obtained by both detectors withoutmore » changing other exposure or geometric parameters. The square of the Fourier transform of each image is taken and divided by the generalized normalized noise power spectrum to give an effective measured task-specific signal-to-noise ratio. This expression is then integrated from 0 to each of the detector’s Nyquist frequencies, and the GM-ROD value is determined by taking a ratio of the integrals for the MAF-CMOS to that of the FPD. The lower bound of integration can be varied to emphasize high frequencies in the detector comparisons. Results: The MAF-CMOS detector exhibits vastly superior performance over the FPD when integrating over all frequencies, yielding a GM-ROD value of 63.1. The lower bound of integration was stepped up in increments of 0.5 cycles/mm for higher frequency comparisons. As the lower bound increased, the GM-ROD value was augmented, reflecting the superior performance of the MAF-CMOS in the high frequency regime. Conclusion: GM-ROD is a versatile metric that can provide quantitative detector and task dependent comparisons that can be used as a basis for detector selection. Supported by NIH Grant: 2R01EB002873 and an equipment grant from Toshiba Medical Systems Corporation.« less

Is There a Limit to the Superiority of Individuals with ASD in Visual Search?

ERIC Educational Resources Information Center

Hessels, Roy S.; Hooge, Ignace T. C.; Snijders, Tineke M.; Kemner, Chantal

2014-01-01

Superiority in visual search for individuals diagnosed with autism spectrum disorder (ASD) is a well-reported finding. We administered two visual search tasks to individuals with ASD and matched controls. One showed no difference between the groups, and one did show the expected superior performance for individuals with ASD. These results offer an…

Development of a MEMS device for acoustic emission testing

NASA Astrophysics Data System (ADS)

Ozevin, Didem; Pessiki, Stephen P.; Jain, Akash; Greve, David W.; Oppenheim, Irving J.

2003-08-01

Acoustic emission testing is an important technology for evaluating structural materials, and especially for detecting damage in structural members. Significant new capabilities may be gained by developing MEMS transducers for acoustic emission testing, including permanent bonding or embedment for superior coupling, greater density of transducer placement, and a bundle of transducers on each device tuned to different frequencies. Additional advantages include capabilities for maintenance of signal histories and coordination between multiple transducers. We designed a MEMS device for acoustic emission testing that features two different mechanical types, a hexagonal plate design and a spring-mass design, with multiple detectors of each type at ten different frequencies in the range of 100 kHz to 1 MHz. The devices were fabricated in the multi-user polysilicon surface micromachining (MUMPs) process and we have conducted electrical characterization experiments and initial experiments on acoustic emission detection. We first report on C(V) measurements and perform a comparison between predicted (design) and measured response. We next report on admittance measurements conducted at pressures varying from vacuum to atmospheric, identifying the resonant frequencies and again providing a comparison with predicted performance. We then describe initial calibration experiments that compare the performance of the detectors to other acoustic emission transducers, and we discuss the overall performance of the device as a sensor suite, as contrasted to the single-channel performance of most commercial transducers.

Pseudoaneurysm of the superior lateral genicular artery: case report of a rare complication after total knee arthroplasty.

PubMed

Saini, Pramod; Meena, Sanjay; Malhotra, Rajesh; Gamanagatti, Shivanand; Kumar, Vijay; Jain, Vaibhav

2013-01-01

Pseudoaneurysm of superior lateral genicular artery following total knee arthroplasty is a rare complication and has been reported following lateral release performed for eversion of patella in a knee with tight lateral structures. This report describes a case of pseudo aneurysm of superior lateral geniculate artery that developed after primary Total knee arthroplasty for a stiff knee in a 68 year old patient. Patient presented with pain and rapidly increasing swelling in early post operative period. Diagnosis was made on duplex ultrasound and confirmed by angiography. Angiographic coil embolisation of the pseudoaneurysm was performed. Since no lateral release was performed in this case, the probable mechanism was shear injury to the vessel. Pseudoaneurysm of superior lateral genicular artery can occur in absence of lateral release by shear injury to an atherosclerotic vessel. Angiographic coil embolisation appears to be the best method for treating such post arthroplasty pseudoaneurysm because of less chance of infection, non interference with rehabilitation and diagnosis and treatment during same procedure.

A Comparison of ACQ, AIE and AEE-Based Polymers Loaded on Polyurethane Foams as Sensors for Explosives Detection.

PubMed

Chu, Zhiwei; Fan, Zhuxin; Zhang, Xiang; Tan, Xiaofeng; Li, Dongxu; Chen, Guohua; Zhao, Qinghua

2018-05-15

An aggregation-caused quenching (ACQ)-active polymer (PF), an aggregation-induced emission (AIE)-active polymer (PFTPE) and an aggregation-enhanced emission (AEE)-active polymer (PTTPE) were synthesized by tetraphenylethane (TPE), fluorene and thiophene moieties. Polyurethane (PU) foams modified by PF, PFTPE and PTTPE, namely PU-PF, PU-PFTPE and PU-PTTPE, using ultrasonication-assisted method have been prepared. A comparative study of PU-PF, PU-PFTPE and PU-PTTPE for detection explosives had been performed, and significant fluorescence quenching was observed with the introduction of PA solutions. The as-prepared PU-PF, PU-PFTPE and PU-PTTPE sensors exhibited a superior sensitivity for PA solutions with different concentrations. Remarkably, PU-PF gave a quenching efficiency of 96.2%, higher than 93.5% for PU-PFTPE and 86.7% for PU-PTTPE at a PA concentration of 180 µg·mL -1 in methanol, which was attributed to the effective energy transfer from the fluorophore (PF) to the nitro explosive (PA). This suggested that some ACQ polymers, applied to detect explosives, could afford better performances than AIE or AEE polymers through modification of structures and selection of adequate carriers. At the same time, these chemical sensors can be recycled many times.

A Comparison of ACQ, AIE and AEE-Based Polymers Loaded on Polyurethane Foams as Sensors for Explosives Detection

PubMed Central

Chu, Zhiwei; Fan, Zhuxin; Zhang, Xiang; Tan, Xiaofeng; Chen, Guohua; Zhao, Qinghua

2018-01-01

An aggregation-caused quenching (ACQ)-active polymer (PF), an aggregation-induced emission (AIE)-active polymer (PFTPE) and an aggregation-enhanced emission (AEE)-active polymer (PTTPE) were synthesized by tetraphenylethane (TPE), fluorene and thiophene moieties. Polyurethane (PU) foams modified by PF, PFTPE and PTTPE, namely PU-PF, PU-PFTPE and PU-PTTPE, using ultrasonication-assisted method have been prepared. A comparative study of PU-PF, PU-PFTPE and PU-PTTPE for detection explosives had been performed, and significant fluorescence quenching was observed with the introduction of PA solutions. The as-prepared PU-PF, PU-PFTPE and PU-PTTPE sensors exhibited a superior sensitivity for PA solutions with different concentrations. Remarkably, PU-PF gave a quenching efficiency of 96.2%, higher than 93.5% for PU-PFTPE and 86.7% for PU-PTTPE at a PA concentration of 180 µg·mL−1 in methanol, which was attributed to the effective energy transfer from the fluorophore (PF) to the nitro explosive (PA). This suggested that some ACQ polymers, applied to detect explosives, could afford better performances than AIE or AEE polymers through modification of structures and selection of adequate carriers. At the same time, these chemical sensors can be recycled many times. PMID:29762497

Highly sensitive hydrogen sulfide (H2 S) gas sensors from viral-templated nanocrystalline gold nanowires

NASA Astrophysics Data System (ADS)

Moon, Chung Hee; Zhang, Miluo; Myung, Nosang V.; Haberer, Elaine D.

2014-04-01

A facile, site-specific viral-templated assembly method was used to fabricate sensitive hydrogen sulfide (H2S) gas sensors at room temperature. A gold-binding M13 bacteriophage served to organize gold nanoparticles into linear arrays which were used as seeds for subsequent nanowire formation through electroless deposition. Nanowire widths and densities within the sensors were modified by electroless deposition time and phage concentration, respectively, to tune device resistance. Chemiresistive H2S gas sensors with superior room temperature sensing performance were produced with sensitivity of 654%/ppmv, theoretical lowest detection limit of 2 ppbv, and 70% recovery within 9 min for 0.025 ppmv. The role of the viral template and associated gold-binding peptide was elucidated by removing organics using a short O2 plasma treatment followed by an ethanol dip. The template and gold-binding peptide were crucial to electrical and sensor performance. Without surface organics, the resistance fell by several orders of magnitude, the sensitivity dropped by more than a factor of 100 to 6%/ppmv, the lower limit of detection increased, and no recovery was detected with dry air flow. Viral templates provide a novel, alternative fabrication route for highly sensitive, nanostructured H2S gas sensors.

Internal-illumination photoacoustic computed tomography

NASA Astrophysics Data System (ADS)

Li, Mucong; Lan, Bangxin; Liu, Wei; Xia, Jun; Yao, Junjie

2018-03-01

We report a photoacoustic computed tomography (PACT) system using a customized optical fiber with a cylindrical diffuser to internally illuminate deep targets. The traditional external light illumination in PACT usually limits the penetration depth to a few centimeters from the tissue surface, mainly due to strong optical attenuation along the light propagation path from the outside in. By contrast, internal light illumination, with external ultrasound detection, can potentially detect much deeper targets. Different from previous internal illumination PACT implementations using forward-looking optical fibers, our internal-illumination PACT system uses a customized optical fiber with a 3-cm-long conoid needle diffuser attached to the fiber tip, which can homogeneously illuminate the surrounding space and substantially enlarge the field of view. We characterized the internal illumination distribution and PACT system performance. We performed tissue phantom and in vivo animal studies to further demonstrate the superior imaging depth using internal illumination over external illumination. We imaged a 7.5-cm-deep leaf target embedded in optically scattering medium and the beating heart of a mouse overlaid with 3.7-cm-thick chicken tissue. Our results have collectively demonstrated that the internal light illumination combined with external ultrasound detection might be a useful strategy to improve the penetration depth of PACT in imaging deep organs of large animals and humans.

Droplet digital PCR-based EGFR mutation detection with an internal quality control index to determine the quality of DNA.

PubMed

Kim, Sung-Su; Choi, Hyun-Jeung; Kim, Jin Ju; Kim, M Sun; Lee, In-Seon; Byun, Bohyun; Jia, Lina; Oh, Myung Ryurl; Moon, Youngho; Park, Sarah; Choi, Joon-Seok; Chae, Seoung Wan; Nam, Byung-Ho; Kim, Jin-Soo; Kim, Jihun; Min, Byung Soh; Lee, Jae Seok; Won, Jae-Kyung; Cho, Soo Youn; Choi, Yoon-La; Shin, Young Kee

2018-01-11

In clinical translational research and molecular in vitro diagnostics, a major challenge in the detection of genetic mutations is overcoming artefactual results caused by the low-quality of formalin-fixed paraffin-embedded tissue (FFPET)-derived DNA (FFPET-DNA). Here, we propose the use of an 'internal quality control (iQC) index' as a criterion for judging the minimum quality of DNA for PCR-based analyses. In a pre-clinical study comparing the results from droplet digital PCR-based EGFR mutation test (ddEGFR test) and qPCR-based EGFR mutation test (cobas EGFR test), iQC index ≥ 0.5 (iQC copies ≥ 500, using 3.3 ng of FFPET-DNA [1,000 genome equivalents]) was established, indicating that more than half of the input DNA was amplifiable. Using this criterion, we conducted a retrospective comparative clinical study of the ddEGFR and cobas EGFR tests for the detection of EGFR mutations in non-small cell lung cancer (NSCLC) FFPET-DNA samples. Compared with the cobas EGFR test, the ddEGFR test exhibited superior analytical performance and equivalent or higher clinical performance. Furthermore, iQC index is a reliable indicator of the quality of FFPET-DNA and could be used to prevent incorrect diagnoses arising from low-quality samples.

Enzyme-free ethanol sensor based on electrospun nickel nanoparticle-loaded carbon fiber paste electrode.

PubMed

Liu, Yang; Zhang, Lei; Guo, Qiaohui; Hou, Haoqing; You, Tianyan

2010-03-24

We have developed a novel nickel nanoparticle-loaded carbon fiber paste (NiCFP) electrode for enzyme-free determination of ethanol. An electrospinning technique was used to prepare the NiCF composite with large amounts of spherical nanoparticles firmly embedded in carbon fibers (CF). In application to electroanalysis of ethanol, the NiCFP electrode exhibited high amperometric response and good operational stability. The calibration curve was linear up to 87.5 mM with a detection limit of 0.25 mM, which is superior to that obtained with other transition metal based electrodes. For detection of ethanol present in liquor samples, the values obtained with the NiCFP electrode were in agreement with the ones declared on the label. The attractive analytical performance and simple preparation method make this novel material promising for the development of effective enzyme-free sensors. Copyright 2010 Elsevier B.V. All rights reserved.

Digital detection of endonuclease mediated gene disruption in the HIV provirus

PubMed Central

Sedlak, Ruth Hall; Liang, Shu; Niyonzima, Nixon; De Silva Feelixge, Harshana S.; Roychoudhury, Pavitra; Greninger, Alexander L.; Weber, Nicholas D.; Boissel, Sandrine; Scharenberg, Andrew M.; Cheng, Anqi; Magaret, Amalia; Bumgarner, Roger; Stone, Daniel; Jerome, Keith R.

2016-01-01

Genome editing by designer nucleases is a rapidly evolving technology utilized in a highly diverse set of research fields. Among all fields, the T7 endonuclease mismatch cleavage assay, or Surveyor assay, is the most commonly used tool to assess genomic editing by designer nucleases. This assay, while relatively easy to perform, provides only a semi-quantitative measure of mutation efficiency that lacks sensitivity and accuracy. We demonstrate a simple droplet digital PCR assay that quickly quantitates a range of indel mutations with detection as low as 0.02% mutant in a wild type background and precision (≤6%CV) and accuracy superior to either mismatch cleavage assay or clonal sequencing when compared to next-generation sequencing. The precision and simplicity of this assay will facilitate comparison of gene editing approaches and their optimization, accelerating progress in this rapidly-moving field. PMID:26829887

Detection of Cheating by Decimation Algorithm

NASA Astrophysics Data System (ADS)

Yamanaka, Shogo; Ohzeki, Masayuki; Decelle, Aurélien

2015-02-01

We expand the item response theory to study the case of "cheating students" for a set of exams, trying to detect them by applying a greedy algorithm of inference. This extended model is closely related to the Boltzmann machine learning. In this paper we aim to infer the correct biases and interactions of our model by considering a relatively small number of sets of training data. Nevertheless, the greedy algorithm that we employed in the present study exhibits good performance with a few number of training data. The key point is the sparseness of the interactions in our problem in the context of the Boltzmann machine learning: the existence of cheating students is expected to be very rare (possibly even in real world). We compare a standard approach to infer the sparse interactions in the Boltzmann machine learning to our greedy algorithm and we find the latter to be superior in several aspects.

Scientific Impact Recognition Award. Sentinel node staging for breast cancer: intraoperative molecular pathology overcomes conventional histologic sampling errors.

PubMed

Blumencranz, Peter; Whitworth, Pat W; Deck, Kenneth; Rosenberg, Anne; Reintgen, Douglas; Beitsch, Peter; Chagpar, Anees; Julian, Thomas; Saha, Sukamal; Mamounas, Eleftherios; Giuliano, Armando; Simmons, Rache

2007-10-01

When sentinel node dissection reveals breast cancer metastasis, completion axillary lymph node dissection is ideally performed during the same operation. Intraoperative histologic techniques have low and variable sensitivity. A new intraoperative molecular assay (GeneSearch BLN Assay; Veridex, LLC, Warren, NJ) was evaluated to determine its efficiency in identifying significant sentinel lymph node metastases (>.2 mm). Positive or negative BLN Assay results generated from fresh 2-mm node slabs were compared with results from conventional histologic evaluation of adjacent fixed tissue slabs. In a prospective study of 416 patients at 11 clinical sites, the assay detected 98% of metastases >2 mm and 88% of metastasis greater >.2 mm, results superior to frozen section. Micrometastases were less frequently detected (57%) and assay positive results in nodes found negative by histology were rare (4%). The BLN Assay is properly calibrated for use as a stand alone intraoperative molecular test.

Detection of Upscale-Crop and Partial Manipulation in Surveillance Video Based on Sensor Pattern Noise

PubMed Central

Hyun, Dai-Kyung; Ryu, Seung-Jin; Lee, Hae-Yeoun; Lee, Heung-Kyu

2013-01-01

In many court cases, surveillance videos are used as significant court evidence. As these surveillance videos can easily be forged, it may cause serious social issues, such as convicting an innocent person. Nevertheless, there is little research being done on forgery of surveillance videos. This paper proposes a forensic technique to detect forgeries of surveillance video based on sensor pattern noise (SPN). We exploit the scaling invariance of the minimum average correlation energy Mellin radial harmonic (MACE-MRH) correlation filter to reliably unveil traces of upscaling in videos. By excluding the high-frequency components of the investigated video and adaptively choosing the size of the local search window, the proposed method effectively localizes partially manipulated regions. Empirical evidence from a large database of test videos, including RGB (Red, Green, Blue)/infrared video, dynamic-/static-scene video and compressed video, indicates the superior performance of the proposed method. PMID:24051524

The Miniaturized Raman System and Detection of Traces of Life in Halite from the Atacama Desert: Some Considerations for the Search for Life Signatures on Mars

PubMed Central

Jehlička, Jan; Edwards, Howell G.M.; Hutchinson, Ian; Ascaso, Carmen; Wierzchos, Jacek

2012-01-01

Abstract Raman spectroscopy is being adopted as a nondestructive instrumentation for the robotic exploration of Mars to search for traces of life in the geological record. Here, miniaturized Raman spectrometers of two different types equipped with 532 and 785 nm lasers for excitation, respectively, were compared for the detection of microbial biomarkers in natural halite from the hyperarid region of the Atacama Desert. Measurements were performed directly on the rock as well as on the homogenized, powdered samples prepared from this material—the effects of this sample preparation and the excitation wavelength employed in the analysis are compared and discussed. From these results, 532 nm excitation was found to be superior for the analysis of powdered specimens due to its high sensitivity toward carotenoids and hence a higher capability for their detection at relatively low concentration in bulk powdered specimens. For the same reason, this wavelength was a better choice for the detection of carotenoids in direct measurements made on the rock samples. The 785 nm excitation wavelength, in contrast, proved to be more sensitive toward the detection of scytonemin. Key Words: Miniaturized portable Raman—Atacama—Mars—Biomarker detection. Astrobiology 12, 1095–1099. PMID:23151300

Rapid and Sensitive Detection of Protein Biomarker Using a Portable Fluorescence Biosensor based on Quantum Dots and a Lateral Flow Test Strip

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zhaohui; Wang, Ying; Wang, Jun

2010-08-15

A portable fluorescence biosensor with rapid and ultrasensitive response for trace protein has been built up with quantum dots and lateral flow test strip. The superior signal brightness and high photostability of quantum dots are combined with the promising advantages of lateral flow test strip and resulted in high sensitivity, selectivity and speedy for protein detection. Nitrated ceruloplasmin, a significant biomarker for cardiovascular disease, lung cancer and stress response to smoking, was used as model protein to demonstrate the good performances of this proposed Qdot-based lateral flow test strip. Quantitative detection of nitrated ceruloplasmin was realized by recording the fluorescencemore » intensity of quantum dots captured on the test line. Under optimal conditions, this portable fluorescence biosensor displays rapid responses for nitrated ceruloplasmin in wide dynamic range with a detection limit of 0.1ng/mL (S/N=3). Furthermore, the biosensor was successfully utilized for spiked human plasma sample detection with the concentration as low as 1ng/mL. The results demonstrate that the quantum dot-based lateral flow test strip is capable for rapid, sensitive, and quantitative detection of nitrated ceruloplasmin and hold a great promise for point-of-care and in field analysis of other protein biomarkers.« less

Ultrahigh-Sensitivity Piezoresistive Pressure Sensors for Detection of Tiny Pressure.

PubMed

Li, Hongwei; Wu, Kunjie; Xu, Zeyang; Wang, Zhongwu; Meng, Yancheng; Li, Liqiang

2018-06-20

High-sensitivity pressure sensors are crucial for the ultrasensitive touch technology and E-skin, especially at the tiny-pressure range below 100 Pa. However, it is highly challenging to substantially promote sensitivity beyond the current level at several to 200 kPa -1 and to improve the detection limit lower than 0.1 Pa, which is significant for the development of pressure sensors toward ultrasensitive and highly precise detection. Here, we develop an efficient strategy to greatly improve the sensitivity near to 2000 kPa -1 using short-channel coplanar device structure and sharp microstructure, which is systematically proposed for the first time and rationalized by the mathematic calculation and analysis. Significantly, benefiting from the ultrahigh sensitivity, the detection limit is improved to be as small as 0.075 Pa. The sensitivity and detection limit are both superior to the current levels and far surpass the function of human skin. Furthermore, the sensor shows fast response time (50 μs), excellent reproducibility and stability, and low power consumption. Remarkably, the sensor shows excellent detection capacity in the tiny-pressure range, including light-emitting diode switching with a pressure of 7 Pa, ringtone (2-20 Pa) recognition, and ultrasensitive (0.1 Pa) electronic glove. This work represents a performance and strategic progress in the field of pressure sensing.

High-Density Dielectrophoretic Microwell Array for Detection, Capture, and Single-Cell Analysis of Rare Tumor Cells in Peripheral Blood.

PubMed

Morimoto, Atsushi; Mogami, Toshifumi; Watanabe, Masaru; Iijima, Kazuki; Akiyama, Yasuyuki; Katayama, Koji; Futami, Toru; Yamamoto, Nobuyuki; Sawada, Takeshi; Koizumi, Fumiaki; Koh, Yasuhiro

2015-01-01

Development of a reliable platform and workflow to detect and capture a small number of mutation-bearing circulating tumor cells (CTCs) from a blood sample is necessary for the development of noninvasive cancer diagnosis. In this preclinical study, we aimed to develop a capture system for molecular characterization of single CTCs based on high-density dielectrophoretic microwell array technology. Spike-in experiments using lung cancer cell lines were conducted. The microwell array was used to capture spiked cancer cells, and captured single cells were subjected to whole genome amplification followed by sequencing. A high detection rate (70.2%-90.0%) and excellent linear performance (R2 = 0.8189-0.9999) were noted between the observed and expected numbers of tumor cells. The detection rate was markedly higher than that obtained using the CellSearch system in a blinded manner, suggesting the superior sensitivity of our system in detecting EpCAM- tumor cells. Isolation of single captured tumor cells, followed by detection of EGFR mutations, was achieved using Sanger sequencing. Using a microwell array, we established an efficient and convenient platform for the capture and characterization of single CTCs. The results of a proof-of-principle preclinical study indicated that this platform has potential for the molecular characterization of captured CTCs from patients.

Assessment of circulating copy number variant detection for cancer screening.

PubMed

Molparia, Bhuvan; Nichani, Eshaan; Torkamani, Ali

2017-01-01

Current high-sensitivity cancer screening methods, largely utilizing correlative biomarkers, suffer from false positive rates that lead to unnecessary medical procedures and debatable public health benefit overall. Detection of circulating tumor DNA (ctDNA), a causal biomarker, has the potential to revolutionize cancer screening. Thus far, the majority of ctDNA studies have focused on detection of tumor-specific point mutations after cancer diagnosis for the purpose of post-treatment surveillance. However, ctDNA point mutation detection methods developed to date likely lack either the scope or analytical sensitivity necessary to be useful for cancer screening, due to the low (<1%) ctDNA fraction derived from early stage tumors. On the other hand, tumor-derived copy number variant (CNV) detection is hypothetically a superior means of ctDNA-based cancer screening for many tumor types, given that, relative to point mutations, each individual tumor CNV contributes a much larger number of ctDNA fragments to the overall pool of circulating free DNA (cfDNA). A small number of studies have demonstrated the potential of ctDNA CNV-based screening in select cancer types. Here we perform an in silico assessment of the potential for ctDNA CNV-based cancer screening across many common cancers, and suggest ctDNA CNV detection shows promise as a broad cancer screening methodology.

Carbon nanoparticle for highly sensitive and selective fluorescent detection of mercury(II) ion in aqueous solution.

PubMed

Li, Hailong; Zhai, Junfeng; Tian, Jingqi; Luo, Yonglan; Sun, Xuping

2011-08-15

In this article, carbon nanoparticles (CNPs) were used as a novel fluorescent sensing platform for highly sensitive and selective Hg(2+) detection. To the best of our knowledge, this is the first example of CNPs obtained from candle soot used in this type of sensor. The general concept used in this approach is based on that adsorption of the fluorescently labeled single-stranded DNA (ssDNA) probe by CNP via π-π stacking interactions between DNA bases and CNP leads to substantial dye fluorescence quenching; however, in the presence of Hg(2+), T-Hg(2+)-T induced hairpin structure does not adsorb on CNP and thus retains the dye fluorescence. A detection limit as low as 10nM was achieved. The present CNP-based biosensor for Hg(2+) detection exhibits remarkable specificity against other possible metal ions. Furthermore, superior selectivity performance was observed when Hg(2+) detection was carried out in the presence of a large amount of other interference ions. Finally, in order to evaluate its potential practical application, Hg(2+) detection was conducted with the use of lake water other than pure buffer and it is believed that it holds great promise for real sample analysis upon further development. Copyright © 2011 Elsevier B.V. All rights reserved.

The role of synovial fluid analysis in the detection of periprosthetic hip and knee infections: a systematic review and meta-analysis.

PubMed

De Fine, Marcello; Giavaresi, Gianluca; Fini, Milena; Illuminati, Andrea; Terrando, Silvio; Pignatti, Giovanni

2018-05-01

This study tried to ascertain (1) the accuracy of synovial fluid white blood cell count and polymorphonucleate percentage in the diagnosis of periprosthetic hip and knee infections, (2) which test yielded superior test performance, and (3) the influence on diagnostic accuracy of study characteristics such as patient number, study design, study level, anatomic site, and threshold value. A systematic search was conducted including papers assessing more effective cutoffs for synovial fluid tests, having comparative design, evaluating an exclusive cohort of hip or knee prostheses, including a clear definition of infected cases, and reporting sufficient data for the calculation of true-positive, false-positive, false-negative, and true-negative. A total of 375 articles were collected and, given the inclusion criteria, ten manuscripts were included. These studies assessed 1155 hip prostheses (276 infected cases) and 1235 knee prostheses (401 infected cases). The specificity of synovial fluid white blood cell count was significantly increased by using the threshold value ≥ 3000 cell/μL (p = 0.006); the sensitivity of polymorphonucleate percentage was significantly higher in detecting knee infections (p = 0.034). Both tests had a high specificity and sensitivity in detecting periprosthetic joint infections, and no clear superiority of one over the other existed. Furthermore, cutoff and anatomic site significantly influenced synovial fluid white blood cell count and polymorphonucleate percentage, respectively. Synovial fluid analysis is adequate in differentiating patients with periprosthetic hip and knee infections. Our data confirms international guidelines suggesting the use of 3000 cell/μL as cutoff threshold for synovial fluid white blood cell count. Since an anatomic site effect has been demonstrated, the goal of future studies will be to identify different cutoffs for hip and knee prostheses.

Binding diversity of antibodies against external and internal epitopes of the multidrug resistance gene product P-glycoprotein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lehne, G.; De Angelis, P.; Clausen, O.P.F.

1995-07-01

P-glycoprotein (Pgp) is a trans-membraneous protein that is associated with multidrug resistance (MDR) in human cancer, including hepatocellular carcinomas and leukemia. There is no consensus regarding methods of choice for analysis of Pgp expression, and development of reliable analytical methods is now essential. We have studied the Pgp expression in human hepatoma and leukemia cell lines using flow cytometry. The aim of the study was to compare binding properties of anti-Pgp antibodies reacting with surface (MRK16, UIC2) and cytoplasmic (C219, JSB-1) epitopes to assess which antibody performed best with respect to fluorescence discrimination. By histogram subtraction the fractions of resistantmore » human hepatoma cells positive for Pgp were 99% (MRK16), 97% (UIC2), 77% (USB-1), and 51% (C219), demonstrating variations in antibody reactivity. The resolution in detecting decreasing levels of Pgp in hepatoma cells was superior for the externally binding antibodies, showing that there is a correlation between antibody reactivity and fluorescence discrimination. Similar results were obtained for parental and resistant KG1a human leukemia cell lines. The Pgp epitopes remained reactive to the anti-Pgp MAbs after methanol fixation and cryopreservation. By dual parameter flow cytometry it was shown that Pgp expression in viable cells may be assessed together with uptake of epirubicin, which was low in cells expressing high levels of Pgp and vice versa. In conclusion, all tested antibodies proved useful for flow cytometric detection of high levels of Pgp, but the externally binding ones were superior in detection of low and variable levels of Pgp. 36 refs., 8 figs., 1 tab.« less

Five common tumor biomarkers and CEA for diagnosing early gastric cancer: A protocol for a network meta-analysis of diagnostic test accuracy.

PubMed

Shen, Minghui; Wang, Hui; Wei, Kongyuan; Zhang, Jianling; You, Chongge

2018-05-01

Although surgical resection is the recommended treatment for the patients with gastric cancer, lots of patients show advanced or metastatic gastric cancer at the time of diagnosis. Detection of gastric cancer at early stages is a huge challenge because of lack of appropriate detection tests. Unfortunately, existing clinical guidelines focusing on early diagnosis of gastric cancer do not provide consistent and prudent evidence. Serum carcinoembryonic antigen was considered as a complementary test, although it is not good enough to diagnose early gastric cancer. There are no other tumor markers recommended for diagnosing early gastric cancer. This study aims to evaluate and compare the diagnostic accuracy of 5 common tumor biomarkers (CA19-9, CA125, PG, IncRNA, and DNA methylation) and CEA and their combinations for diagnosing gastric cancer through network meta-analysis method, and to rank these tests using a superiority index. PubMed, EMBASE.com, and the Cochrane Central Register of Controlled Trials (CENTRAL) will be searched from their inception to March 2018. We will include diagnostic tests which assessed the accuracy of the above-mentioned tumor biomarkers and CEA for diagnosing gastric cancer. The risk of bias for each study will be independently assessed as low, moderate, or high using criteria adapted from Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Network meta-analysis will be performed using STATA 12.0 and R 3.4.1 software. The competing diagnostic tests will be ranked by a superiority index. This study is ongoing and will be submitted to a peer-reviewed journal for publication. This study will provide systematically suggestions to select different tumor biomarkers for detecting the early gastric cancer.

Functional electrospun nanofibers for multimodal sensitive detection of biogenic amines in food via a simple dipstick assay.

PubMed

Yurova, Nadezhda S; Danchuk, Alexandra; Mobarez, Sarah N; Wongkaew, Nongnoot; Rusanova, Tatiana; Baeumner, Antje J; Duerkop, Axel

2018-01-01

Electrospun nanofibers (ENFs) are promising materials for rapid diagnostic tests like lateral flow assays and dipsticks because they offer an immense surface area while excluding minimal volume, a variety of functional surface groups, and can entrap functional additives within their interior. Here, we show that ENFs on sample pads are superior in comparison to standard polymer membranes for the optical detection of biogenic amines (BAs) in food using a dipstick format. Specifically, cellulose acetate (CA) fibers doped with 2 mg/mL of the chromogenic and fluorogenic amine-reactive chameleon dye Py-1 were electrospun into uniform anionic mats. Those extract cationic BAs from real samples and Py-1 transduces BA concentrations into a change of color, reflectance, and fluorescence. Dropping a BA sample onto the nanofiber mat converts the weakly fluorescent pyrylium dye Py-1 into a strongly red emitting pyridinium dye. For the first time, a simple UV lamp excites fluorescence and a digital camera acts as detector. The intensity ratio of the red to the blue channel of the digital image is dependent on the concentration of most relevant BAs indicating food spoilage from 10 to 250 μM. This matches the permitted limits for BAs in foods and no false positive signals arise from secondary and tertiary amines. BA detection in seafood samples was also demonstrated successfully. The nanofiber mat dipsticks were up to sixfold more sensitive than those using a polymer membrane with the same dye embedded. Hence, nanofiber-based tests are not only superior to polymer-based dipstick assays, but will also improve the performance of established tests related to food safety, medical diagnostics, and environmental testing. Graphical Absract ᅟ.

Adaptability and stability of soybean genotypes in off-season cultivation.

PubMed

Batista, R O; Hamawaki, R L; Sousa, L B; Nogueira, A P O; Hamawaki, O T

2015-08-14

The oil and protein contents of soybean grains are important quantitative traits for use in breeding. However, few breeding programs perform selection based on these traits in different environments. This study assessed the adaptability and stability of 14 elite early soybean breeding lines in off-season cultivation with respect to yield, and oil and protein contents. A range of statistical methods was applied and these analyses indicated that for off-season cultivation, the lines UFUS 5 and UFUS 10 could be recommended due to their superior performance in grain yield, oil content, and specific adaptability to unfavorable environments along with high stability in these characteristics. Also recommended were UFUS 06, which demonstrated superior performance in all three tested characteristics and showed adaptation to favorable environments, and UFUS 13, which showed high adaptability and stability and a superior performance for protein content.

Assessment of a combined gas chromatography mass spectrometer sensor (GC-MSS) system for detecting biologically relevant volatile compounds (VCs).

PubMed

Gould, Oliver; Wieczorek, Tomas; de Lacy Costello, Ben P J; Persad, Raj; Ratcliffe, Norman

2017-09-26

There have been a number of studies in which metal oxide sensors (MOS) have replaced conventional analytical detectors in gas chromatography systems. However, despite the use of these instruments in a range of applications including breath research the sensor responses (i.e. resistance changes w.r.t. concentration of VCs) remain largely unreported. This paper addresses that issue by comparing the response of a metal oxide sensor directly with a mass spectrometer (MS), whereby both detectors are interfaced to the same GC column using an s-swafer. It was demonstrated that the sensitivity of an in-house fabricated ZnO/ SnO2 thick film MOS was superior to a modern MS for the detection of a wide range of volatile compounds (VCs) of different functionalities and masses. Better techniques for detection and quantification of these VCs is valuable, as many of these compounds are commonly reported throughout the scientific literature. This is also the first published report of a combined GC-MS sensor system. These 2 different detector technologies when combined, should enhance discriminatory abilities to aid disease diagnoses using volatiles from e.g. breath, and bodily fluids. 29 chemical standards have been tested using solid phase micro-extraction; 25 of these compounds are found on human breath. In all but 2 instances the sensor exhibited the same or superior limit of detection compared to the MS. 12 stool samples from healthy participants were analysed, the sensor detected, on average 1.6 peaks more per sample than the MS. Similarly analysing the headspace of E. coli broth cultures the sensor detected 6.9 more peaks per sample versus the MS. This greater sensitivity is primarily a function of the superior limits of detection of the metal oxide sensor. This shows that systems based on the combination of chromatography systems with solid state sensors shows promise for a range of applications. © 2017 IOP Publishing Ltd.

Assessment of a combined gas chromatography mass spectrometer sensor system for detecting biologically relevant volatile compounds.

PubMed

Gould, Oliver; Wieczorek, Tom; de Lacy Costello, Ben; Persad, Raj; Ratcliffe, Norman

2017-12-06

There have been a number of studies in which metal oxide sensors (MOS) have replaced conventional analytical detectors in gas chromatography systems. However, despite the use of these instruments in a range of applications including breath research the sensor responses (i.e. resistance changes w.r.t. concentration of VCs) remain largely unreported. This paper addresses that issue by comparing the response of a metal oxide sensor directly with a mass spectrometer (MS), whereby both detectors are interfaced to the same GC column using an s-swafer. It was demonstrated that the sensitivity of an in-house fabricated ZnO/SnO 2 thick film MOS was superior to a modern MS for the detection of a wide range of volatile compounds (VCs) of different functionalities and masses. Better techniques for detection and quantification of these VCs is valuable, as many of these compounds are commonly reported throughout the scientific literature. This is also the first published report of a combined GC-MS sensor system. These two different detector technologies when combined, should enhance discriminatory abilities to aid disease diagnoses using volatiles from e.g. breath, and bodily fluids. Twenty-nine chemical standards have been tested using solid phase micro-extraction; 25 of these compounds are found on human breath. In all but two instances the sensor exhibited the same or superior limit of detection compared to the MS. Twelve stool samples from healthy participants were analysed; the sensor detected, on average 1.6 peaks more per sample than the MS. Similarly, analysing the headspace of E. coli broth cultures the sensor detected 6.9 more peaks per sample versus the MS. This greater sensitivity is primarily a function of the superior limits of detection of the metal oxide sensor. This shows that systems based on the combination of chromatography systems with solid state sensors shows promise for a range of applications.

The Hidden Snake in the Grass: Superior Detection of Snakes in Challenging Attentional Conditions

PubMed Central

Soares, Sandra C.; Lindström, Björn; Esteves, Francisco; Öhman, Arne

2014-01-01

Snakes have provided a serious threat to primates throughout evolution. Furthermore, bites by venomous snakes still cause significant morbidity and mortality in tropical regions of the world. According to the Snake Detection Theory (SDT Isbell, 2006; 2009), the vital need to detect camouflaged snakes provided strong evolutionary pressure to develop astute perceptual capacity in animals that were potential targets for snake attacks. We performed a series of behavioral tests that assessed snake detection under conditions that may have been critical for survival. We used spiders as the control stimulus because they are also a common object of phobias and rated negatively by the general population, thus commonly lumped together with snakes as “evolutionary fear-relevant”. Across four experiments (N = 205) we demonstrate an advantage in snake detection, which was particularly obvious under visual conditions known to impede detection of a wide array of common stimuli, for example brief stimulus exposures, stimuli presentation in the visual periphery, and stimuli camouflaged in a cluttered environment. Our results demonstrate a striking independence of snake detection from ecological factors that impede the detection of other stimuli, which suggests that, consistent with the SDT, they reflect a specific biological adaptation. Nonetheless, the empirical tests we report are limited to only one aspect of this rich theory, which integrates findings across a wide array of scientific disciplines. PMID:25493937

The Hidden Snake in the Grass: Superior Detection of Snakes in Challenging Attentional Conditions.

PubMed

Soares, Sandra C; Lindström, Björn; Esteves, Francisco; Ohman, Arne

2014-01-01

Snakes have provided a serious threat to primates throughout evolution. Furthermore, bites by venomous snakes still cause significant morbidity and mortality in tropical regions of the world. According to the Snake Detection Theory (SDT Isbell, 2006; 2009), the vital need to detect camouflaged snakes provided strong evolutionary pressure to develop astute perceptual capacity in animals that were potential targets for snake attacks. We performed a series of behavioral tests that assessed snake detection under conditions that may have been critical for survival. We used spiders as the control stimulus because they are also a common object of phobias and rated negatively by the general population, thus commonly lumped together with snakes as "evolutionary fear-relevant". Across four experiments (N = 205) we demonstrate an advantage in snake detection, which was particularly obvious under visual conditions known to impede detection of a wide array of common stimuli, for example brief stimulus exposures, stimuli presentation in the visual periphery, and stimuli camouflaged in a cluttered environment. Our results demonstrate a striking independence of snake detection from ecological factors that impede the detection of other stimuli, which suggests that, consistent with the SDT, they reflect a specific biological adaptation. Nonetheless, the empirical tests we report are limited to only one aspect of this rich theory, which integrates findings across a wide array of scientific disciplines.

Recognition Memory and Source Memory in Autism Spectrum Disorder: A Study of the Intention Superiority and Enactment Effects

ERIC Educational Resources Information Center

Grainger, Catherine; Williams, David M.; Lind, Sophie E.

2017-01-01

It is well established that neurotypical individuals generally show better memory for actions they have performed than actions they have observed others perform or merely read about, a so-called "enactment effect." Strikingly, research has also shown that neurotypical individuals demonstrate superior memory for actions they…

Caged Fish Studies to Detect and Monitor Contaminants of Emerging Concern in the Great Lakes

EPA Science Inventory

Effects-based monitoring studies were conducted in the St. Louis Harbor, Lake Superior, in support of the Great Lakes Restoration Initiative (GLRI). The overall goal of the research was to develop and validate methods using caged fish exposures to detect and monitor contaminants...

Anomaly Detection in the Right Hemisphere: The Influence of Visuospatial Factors

ERIC Educational Resources Information Center

Smith, Stephen D.; Dixon, Michael J.; Tays, William J.; Bulman-Fleming, M. Barbara

2004-01-01

Previous research with both brain-damaged and neurologically intact populations has demonstrated that the right cerebral hemisphere (RH) is superior to the left cerebral hemisphere (LH) at detecting anomalies (or incongruities) in objects (Ramachandran, 1995; Smith, Tays, Dixon, & Bulman-Fleming, 2002). The current research assesses whether the RH…

Centrifugal microfluidic platform for ultrasensitive detection of Botulinum Toxin

USDA-ARS?s Scientific Manuscript database

Botulinum neurotoxin – a global public health threat and category A bioterrorism agent - is the most toxic substance known and one of the most challenging toxins to detect due to its lethality at extremely low concentrations. Hence the live-mouse bioassay because of its superior sensitivity, remains...

Lesion detectability in 2D-mammography and digital breast tomosynthesis using different targets and observers

NASA Astrophysics Data System (ADS)

Elangovan, Premkumar; Mackenzie, Alistair; Dance, David R.; Young, Kenneth C.; Wells, Kevin

2018-05-01

This work investigates the detection performance of specialist and non-specialist observers for different targets in 2D-mammography and digital breast tomosynthesis (DBT) using the OPTIMAM virtual clinical trials (VCT) Toolbox and a 4-alternative forced choice (4AFC) assessment paradigm. Using 2D-mammography and DBT images of virtual breast phantoms, we compare the detection limits of simple uniform spherical targets and irregular solid masses. Target diameters of 4 mm and 6 mm have been chosen to represent target sizes close to the minimum detectable size found in breast screening, across a range of controlled contrast levels. The images were viewed by a set of specialist observers (five medical physicists and six experienced clinical readers) and five non-specialists. Combined results from both observer groups indicate that DBT has a significantly lower detectable threshold contrast than 2D-mammography for small masses (4 mm: 2.1% [DBT] versus 6.9% [2D]; 6 mm: 0.7% [DBT] versus 3.9% [2D]) and spheres (4 mm: 2.9% [DBT] versus 5.3% [2D]; 6 mm: 0.3% [DBT] versus 2.2% [2D]) (p  <  0.0001). Both observer groups found spheres significantly easier to detect than irregular solid masses for both sizes and modalities (p  <  0.0001) (except 4 mm DBT). The detection performances of specialist and non-specialist observers were generally found to be comparable, where each group marginally outperformed the other in particular detection tasks. Within the specialist group, the clinical readers performed better than the medical physicists with irregular masses (p  <  0.0001). The results indicate that using spherical targets in such studies may produce over-optimistic detection thresholds compared to more complex masses, and that the superiority of DBT for detecting masses over 2D-mammography has been quantified. The results also suggest specialist observers may be supplemented by non-specialist observers (with training) in some types of 4AFC studies.

a Single-Exposure Dual-Energy Computed Radiography Technique for Improved Nodule Detection and Classification in Chest Imaging

NASA Astrophysics Data System (ADS)

Zink, Frank Edward

The detection and classification of pulmonary nodules is of great interest in chest radiography. Nodules are often indicative of primary cancer, and their detection is particularly important in asymptomatic patients. The ability to classify nodules as calcified or non-calcified is important because calcification is a positive indicator that the nodule is benign. Dual-energy methods offer the potential to improve both the detection and classification of nodules by allowing the formation of material-selective images. Tissue-selective images can improve detection by virtue of the elimination of obscuring rib structure. Bone -selective images are essentially calcium images, allowing classification of the nodule. A dual-energy technique is introduced which uses a computed radiography system to acquire dual-energy chest radiographs in a single-exposure. All aspects of the dual-energy technique are described, with particular emphasis on scatter-correction, beam-hardening correction, and noise-reduction algorithms. The adaptive noise-reduction algorithm employed improves material-selective signal-to-noise ratio by up to a factor of seven with minimal sacrifice in selectivity. A clinical comparison study is described, undertaken to compare the dual-energy technique to conventional chest radiography for the tasks of nodule detection and classification. Observer performance data were collected using the Free Response Observer Characteristic (FROC) method and the bi-normal Alternative FROC (AFROC) performance model. Results of the comparison study, analyzed using two common multiple observer statistical models, showed that the dual-energy technique was superior to conventional chest radiography for detection of nodules at a statistically significant level (p < .05). Discussion of the comparison study emphasizes the unique combination of data collection and analysis techniques employed, as well as the limitations of comparison techniques in the larger context of technology assessment.

A rapid and convenient method for detecting a broad spectrum of malignant cells from malignant pleuroperitoneal effusion of patients using a multifunctional NIR heptamethine dye.

PubMed

Tian, Ying; Sun, Jing; Yan, Huaijiang; Teng, Zhaogang; Zeng, Leyong; Liu, Ying; Li, Yanjun; Wang, Jiandong; Wang, Shouju; Lu, Guangming

2015-02-07

Detection of malignant cells from malignant effusion is crucial to establish or adjust therapies of patients with cancer. The conventional qualitative detection in malignant pleuroperitoneal effusion is cytological analysis, which is time-consuming and complicated. Therefore, a faster and more convenient detection strategy is urgently needed. In this study, we report a rapid method to detect malignant cells from malignant pleuroperitoneal effusion (hydrothorax and ascites) of patients using IR-808, a tumor-targeted near-infrared (NIR) fluorescent heptamethine dye (tNRI dye), which exhibited superior labeling efficacy without specific conjugation to biomarkers. The targeted imaging performance toward malignant cells using IR-808 was confirmed by comparing with normal cells, and the fluorescence stability assay of IR-808 in malignant effusion was performed from 1 h to 48 h. In order to save time and dose, the incubation time and concentration were optimized to 10 min and 5 μM, which were used to detect malignant cells from 28 clinical samples of malignant pleuroperitoneal effusion. The results revealed that IR-808 could be internalized selectively by malignant cells of samples, and these malignant cells could be easily distinguished from normal cells under a fluorescence microscope. The positive rates between cytological analysis and the IR-808 staining method were 86% (24/28) and 79% (22/28), respectively. An excellent concordance level (Kappa = 0.752, P < 0.001) was observed between the two methods. Our results indicated that IR-808, a new NIR fluorescent heptamethine dye with unique optical imaging and tumor targeting properties, could provide a fast and simple way to detect a broad spectrum of malignant cells from malignant pleuroperitoneal effusion in patients.

Performance metrics for state-of-the-art airborne magnetic and electromagnetic systems for mapping and detection of unexploded ordnance

NASA Astrophysics Data System (ADS)

Doll, William E.; Bell, David T.; Gamey, T. Jeffrey; Beard, Les P.; Sheehan, Jacob R.; Norton, Jeannemarie

2010-04-01

Over the past decade, notable progress has been made in the performance of airborne geophysical systems for mapping and detection of unexploded ordnance in terrestrial and shallow marine environments. For magnetometer systems, the most significant improvements include development of denser magnetometer arrays and vertical gradiometer configurations. In prototype analyses and recent Environmental Security Technology Certification Program (ESTCP) assessments using new production systems the greatest sensitivity has been achieved with a vertical gradiometer configuration, despite model-based survey design results which suggest that dense total-field arrays would be superior. As effective as magnetometer systems have proven to be at many sites, they are inadequate at sites where basalts and other ferrous geologic formations or soils produce anomalies that approach or exceed those of target ordnance items. Additionally, magnetometer systems are ineffective where detection of non-ferrous ordnance items is of primary concern. Recent completion of the Battelle TEM-8 airborne time-domain electromagnetic system represents the culmination of nearly nine years of assessment and development of airborne electromagnetic systems for UXO mapping and detection. A recent ESTCP demonstration of this system in New Mexico showed that it was able to detect 99% of blind-seeded ordnance items, 81mm and larger, and that it could be used to map in detail a bombing target on a basalt flow where previous airborne magnetometer surveys had failed. The probability of detection for the TEM-8 in the blind-seeded study area was better than that reported for a dense-array total-field magnetometer demonstration of the same blind-seeded site, and the TEM-8 system successfully detected these items with less than half as many anomaly picks as the dense-array total-field magnetometer system.

A Versatile Nanowire Platform for Highly Efficient Isolation and Direct PCR-free Colorimetric Detection of Human Papillomavirus DNA from Unprocessed Urine

PubMed Central

Lee, HyungJae; Choi, Mihye; Hwang, Sang-Hyun; Cho, Youngnam

2018-01-01

Purpose: As human papillomavirus (HPV) is primarily responsible for the development of cervical cancer, significant efforts have been devoted to develop novel strategies for detecting and identifying HPV DNA in urine. The analysis of target DNA sequences in urine offers a potential alternative to conventional methods as a non-invasive clinical screening and diagnostic assessment tool for the detection of HPV. However, the lack of efficient approaches to isolate and directly detect HPV DNA in urine has restricted its potential clinical use. In this study, we demonstrated a novel approach of using polyethylenimine-conjugated magnetic polypyrrole nanowires (PEI-mPpy NWs) for the extraction, identification, and PCR-free colorimetric detection of high-risk strains of HPV DNA sequences, particularly HPV-16 and HPV-18, in urine specimens of cervical cancer patients. Materials and Methods: We fabricated and characterized polyethylenimine-conjugated magnetic nanowires (PEI/mPpy NWs). PEI/mPpy NWs-based HPV DNA isolation and detection strategy appears to be a cost-effective and practical technology with greater sensitivity and accuracy than other urine-based methods. Results: The analytical and clinical performance of PEI-mPpy NWs was evaluated and compared with those of cervical swabs, demonstrating a superior type-specific concordance rate of 100% between urine and cervical swabs, even when using a small volume of urine (300 µL). Conclusion: We envision that PEI-mPpy NWs provide substantive evidence for clinical diagnosis and management of HPV-associated disease with their excellent performance in the recovery and detection of HPV DNA from minimal amounts of urine samples. PMID:29290816

A History of U.S. Navy Periscope Detection Radar, Sensor Design and Development

DTIC Science & Technology

2014-12-31

A History of U.S. Navy Periscope Detection Radar Sensor Design and Development John G. Shannon Paul M. Moser Rite-Solutions, Inc...superiority through the years. Highly effective radar sensors used for military applications were originally large ground-based units designed, developed...automatically. Until very recently, all fleet operational periscope detection radar (PDR) sensor systems have required a skilled and alert human

Real-time PCR assay is superior to other methods for the detection of mycoplasma contamination in the cell lines of the National Cell Bank of Iran.

PubMed

Molla Kazemiha, Vahid; Bonakdar, Shahin; Amanzadeh, Amir; Azari, Shahram; Memarnejadian, Arash; Shahbazi, Shirin; Shokrgozar, Mohammad Ali; Mahdian, Reza

2016-08-01

Mycoplasmas are the most important contaminants of cell cultures throughout the world. They are considered as a major problem in biological studies and biopharmaceutical economic issues. In this study, our aim was to find the best standard technique as a rapid method with high sensitivity, specificity and accuracy for the detection of mycoplasma contamination in the cell lines of the National Cell Bank of Iran. Thirty cell lines suspected to mycoplasma contamination were evaluated by five different techniques including microbial culture, indirect DNA DAPI staining, enzymatic mycoalert(®) assay, conventional PCR and real-time PCR. Five mycoplasma-contaminated cell lines were assigned as positive controls and five mycoplasma-free cell lines as negative controls. The enzymatic method was performed using the mycoalert(®) mycoplasma detection kit. Real-time PCR technique was conducted by PromoKine diagnostic kits. In the conventional PCR method, mycoplasma genus-specific primers were designed to analyze the sequences based on a fixed and common region on 16S ribosomal RNA with PCR product size of 425 bp. Mycoplasma contamination was observed in 60, 56.66, 53.33, 46.66 and 33.33 % of 30 different cell cultures by real-time PCR, PCR, enzymatic mycoalert(®), indirect DNA DAPI staining and microbial culture methods, respectively. The analysis of the results of the different methods showed that the real-time PCR assay was superior the other methods with the sensitivity, specificity, accuracy, predictive value of positive and negative results of 100 %. These values were 94.44, 100, 96.77, 100 and 92.85 % for the conventional PCR method, respectively. Therefore, this study showed that real-time PCR and PCR assays based on the common sequences in the 16S ribosomal RNA are reliable methods with high sensitivity, specificity and accuracy for detection of mycoplasma contamination in cell cultures and other biological products.

Three-dimensional constructive interference in steady-state magnetic resonance imaging in syringomyelia: advantages over conventional imaging.

PubMed

Roser, Florian; Ebner, Florian H; Danz, Søren; Riether, Felix; Ritz, Rainer; Dietz, Klaus; Naegele, Thomas; Tatagiba, Marcos S

2008-05-01

Neuroradiology has become indispensable in detecting the pathophysiology in syringomyelia. Constructive interference in steady-state (CISS) magnetic resonance (MR) imaging can provide superior contrast at the sub-arachnoid tissue borders. As this region is critical in preoperative evaluation, the authors hypothesized that CISS imaging would provide superior assessment of syrinx pathology and surgical planning. Based on records collected from a database of 130 patients with syringomyelia treated at the authors' institution, 59 patients were prospectively evaluated with complete neuroradiological examinations. In addition to routine acquisitions with FLAIR, T1- and T2-weighted, and contrast-enhanced MR imaging series, the authors obtained sagittal cardiac-gated sequences to visualize cerebrospinal fluid (CSF) pulsations and axial 3D CISS MR sequences to detect focal arachnoid webs. Statistical qualitative and quantitative evaluations of spinal cord/CSF contrast, spinal cord/CSF delineation, motion artifacts, and artifacts induced by pulsatile CSF flow were performed. The 3D CISS MR sequences demonstrated a contrast-to-noise ratio significantly better than any other routine imaging sequence (p < 0.001). Moreover, 3D CISS imaging can detect more subarachnoid webs and cavitations in the syrinx than T2-weighted MR imaging with less flow-void artifact. The limitation of 3D CISS imaging is a susceptibility to motion artifacts that can cause reduced spatial resolution. Lengthy acquisition times for axial segments can be reduced with multiplanar reconstruction of 3D CISS-generated sagittal images. Constructive interference in steady-state imaging is the MR sequence of choice in the preoperative evaluation of syringomyelia, allowing significantly higher detection rates of focal subarachnoid webs, whereas standard T2-weighted MR imaging shows turbulent CSF flow voids. Constructive interference in steady-state MR imaging enables the neurosurgeon to accurately identify cases requiring decompression for obstructed CSF. Motion artifacts can be eliminated with technical variations.

Evaluation of conventional PCR for detection of Strongylus vulgaris on horse farms.

PubMed

Bracken, M K; Wøhlk, C B M; Petersen, S L; Nielsen, M K

2012-03-23

Strongyle parasites are ubiquitous in grazing horses. Of these, the bloodworm Strongylus vulgaris is regarded as most pathogenic. Increasing levels of anthelmintic resistance in strongyle parasites has led to recommendations of decreased treatment intensities, and there is now a pronounced need for reliable tools for detection of parasite burdens in general and S. vulgaris in particular. The only method currently available for diagnosing S. vulgaris in practice is the larval culture, which is laborious and time-consuming, so veterinary practitioners most often pool samples from several horses together in one culture to save time. Recently, molecular tools have been developed to detect S. vulgaris in faecal samples. The aim of this study was to compare the performance of a conventional polymerase chain reaction (PCR) assay with the traditional larval culture and furthermore test the performance of pooled versus individual PCR for farm screening purposes. Faecal samples were obtained from 331 horses on 18 different farms. Farm size ranged from 6 to 56 horses, and horses aged between 2 months and 31 years. Larval cultures and PCR were performed individually on all horses. In addition, PCR was performed on 66 faecal pools consisting of 3-5 horses each. Species-specific PCR primers previously developed were used for the PCR. PCR and larval culture detected S. vulgaris in 12.1 and 4.5% of individual horses, respectively. On the farm level, eight farms tested positive with the larval culture, while 13 and 11 farms were positive with the individual and pooled PCRs, respectively. The individual PCR method was statistically superior to the larval culture, while no statistical difference could be detected between pooled and individual PCR for farm screening. In conclusion, pooled PCR appears to be a useful tool for farm screening for S. vulgaris. Copyright © 2011 Elsevier B.V. All rights reserved.

Audiovisual synchrony enhances BOLD responses in a brain network including multisensory STS while also enhancing target-detection performance for both modalities

PubMed Central

Marchant, Jennifer L; Ruff, Christian C; Driver, Jon

2012-01-01

The brain seeks to combine related inputs from different senses (e.g., hearing and vision), via multisensory integration. Temporal information can indicate whether stimuli in different senses are related or not. A recent human fMRI study (Noesselt et al. [2007]: J Neurosci 27:11431–11441) used auditory and visual trains of beeps and flashes with erratic timing, manipulating whether auditory and visual trains were synchronous or unrelated in temporal pattern. A region of superior temporal sulcus (STS) showed higher BOLD signal for the synchronous condition. But this could not be related to performance, and it remained unclear if the erratic, unpredictable nature of the stimulus trains was important. Here we compared synchronous audiovisual trains to asynchronous trains, while using a behavioral task requiring detection of higher-intensity target events in either modality. We further varied whether the stimulus trains had predictable temporal pattern or not. Synchrony (versus lag) between auditory and visual trains enhanced behavioral sensitivity (d') to intensity targets in either modality, regardless of predictable versus unpredictable patterning. The analogous contrast in fMRI revealed BOLD increases in several brain areas, including the left STS region reported by Noesselt et al. [2007: J Neurosci 27:11431–11441]. The synchrony effect on BOLD here correlated with the subject-by-subject impact on performance. Predictability of temporal pattern did not affect target detection performance or STS activity, but did lead to an interaction with audiovisual synchrony for BOLD in inferior parietal cortex. PMID:21953980

Aging and the picture superiority effect in recall.

PubMed

Winograd, E; Smith, A D; Simon, E W

1982-01-01

One recurrent theme in the literature on aging and memory is that the decline of memory for nonverbal information is steeper than for verbal information. This research compares verbal and visual encoding using the picture superiority effect, the finding that pictures are remembered better than words. In the first experiment, an interaction was found between age and type of material; younger subjects recalled more pictures than words while older subjects did not. However, the overall effect was small and two further experiments were conducted. In both of these experiments, the picture superiority effect was found in both age groups with no interaction. In addition, performing a semantic orienting task had no effect on recall. The finding of a picture superiority effect in older subjects indicates that nonverbal codes can be effectively used by subjects in all age groups to facilitate memory performance.

Assessing and benchmarking multiphoton microscopes for biologists

PubMed Central

Corbin, Kaitlin; Pinkard, Henry; Peck, Sebastian; Beemiller, Peter; Krummel, Matthew F.

2017-01-01

Multiphoton microscopy has become staple tool for tracking cells within tissues and organs due to superior depth of penetration, low excitation volumes, and reduced phototoxicity. Many factors, ranging from laser pulse width to relay optics to detectors and electronics, contribute to the overall ability of these microscopes to excite and detect fluorescence deep within tissues. However, we have found that there are few standard ways already described in the literature to distinguish between microscopes or to benchmark existing microscopes to measure the overall quality and efficiency of these instruments. Here, we discuss some simple parameters and methods that can either be used within a multiphoton facility or by a prospective purchaser to benchmark performance. This can both assist in identifying decay in microscope performance and in choosing features of a scope that are suited to experimental needs. PMID:24974026

Performance analysis of MISO multi-hop FSO links over log-normal channels with fog and beam divergence attenuations

NASA Astrophysics Data System (ADS)

Abaza, Mohamed; Mesleh, Raed; Mansour, Ali; Aggoune, el-Hadi

2015-01-01

The performance analysis of a multi-hop decode and forward relaying free-space optical (FSO) communication system is presented in this paper. The considered FSO system uses intensity modulation and direct detection as means of transmission and reception. Atmospheric turbulence impacts are modeled as a log-normal channel, and different weather attenuation effects and geometric losses are taken into account. It is shown that multi-hop is an efficient technique to mitigate such effects in FSO communication systems. A comparison with direct link and multiple-input single-output (MISO) systems considering correlation effects at the transmitter is provided. Results show that MISO multi-hop FSO systems are superior than their counterparts over links exhibiting high attenuation. Monte Carlo simulation results are provided to validate the bit error rate (BER) analyses and conclusions.

A cost-effective process to prepare VO{sub 2} (M) powder and films with superior thermochromic properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiao, Xiudi; Zhang, Hua; Chai, Guanqi

2014-03-01

Graphical abstract: Combining codeposition and short time post annealing, VO{sub 2} (M) with high quality and excellent phase transition performance is obtained. After mixing the VO{sub 2} powder with acrylic resin, the composite films deposited on glass show superior visible transmission and solar modulation, which can be used as an excellent candidate of low cost smart window in energy saving field. - Highlights: • The VO{sub 2} powder obtained by short time thermolysis method is high purity and crystallinity with superior phase transition performance. • The maximum decreasing efficiency of phase transition temperature is about −30 K/at% with w =more » 0.4 at%. • After mixing VO{sub 2} powder with acrylic resin, the maximal visible transmission of the composite films is 48% and the transmission modulation at 2000 nm is 37.3% with phase transition temperature of 66.2 °C. • Though the phase transition performance is weakened by tungsten doping, the film prepared by 1.3 at% tungsten doped VO{sub 2} still show superior transmission modulation about 26.4%, which means that it is a potential candidate as smart windows. - Abstract: VO{sub 2} powder with superior phase transition performance was prepared by convenient thermolysis method. The results illustrated that VO{sub 2} powder show high purity and crystallinity. VO{sub 2} particles are transformed from cluster to quasi-sphere with the increase of annealing temperature. The DSC analysis proves that VO{sub 2} show superior phase transition performance around 68 °C. The phase transition temperature can be reduced to 33.5 °C by 1.8 at% tungsten doping. The maximum decreasing efficiency of phase transition temperature is about −30 K/at% with w = 0.4 at%. After mixing VO{sub 2} powder with acrylic resin, the maximal visible transmission of the composite thin films on glass is 48% and the transmission modulation at 2000 nm is 37.3% with phase transition temperature of 66.2 °C. Though the phase transition performance is weakened by tungsten doping, the film prepared by 1.3 at% tungsten doped VO{sub 2} still show superior transmission modulation about 26.4% at 2000 nm, which means that it is a potential candidate as smart windows.« less

Do Children with Visual Impairments Demonstrate Superior Short-term Memory, Memory Strategies, and Metamemory?

ERIC Educational Resources Information Center

Wyver, Shirley R.; Markham, Roslyn

1998-01-01

This study compared the memory processes underpinning the performance of 19 children with visual impairments and 19 sighted children on the Digit Span subtest of the Wechsler Intelligence Scales. No support was found for claims of the superior performance of children with visual impairments on the subtest nor of a greater awareness of memory…

The efficiency of sonography in diagnosing volvulus in neonates with suspected intestinal malrotation

PubMed Central

Zhang, Wenhua; Sun, Hongjun; Luo, Fangqiong

2017-01-01

Abstract This study is to prospectively evaluate the efficiency of sonography for volvulus diagnosis in neonates with clinically suspected intestinal malrotation. A total of 83 patients with suspected intestinal malrotation who underwent detailed abdominal sonography and upper gastrointestinal contrast study were included. Malrotation was characterized by inversion of the superior mesenteric artery (SMA) and superior mesenteric vein (SMV) in sonographic examination. The “whirlpool sign” of Color Doppler Sonography was recognized as a characteristic for malrotation with volvulus. The degrees of rotation of the SMV winding around SMA were also detected by sonography. Surgery was performed in patients with sonography diagnosed malrotation. A total of 39 patients were sonographically diagnosed as malrotation which was subsequently confirmed by surgery. The sensitivity and positive predictive value of the sonographic diagnosis were both 100% (39/39). The sensitivity, specificity and accuracy of “whirlpool sign” for the detection of midgut volvulus were 95.2% (20/21), 88.9% (16/18), and 92.3% (36/39), respectively. Greater degrees of rotation (equal or greater than 720°) showed higher risk (odds ratio, 5.0; P < .01) for intestinal necrosis occurrence. Sonography is more accurate in diagnosing suspected malrotation than upper gastrointestinal contrast study. Specific sonographic “whirlpool sign” related to volvulus may be used as a potential indicator for intestinal necrosis. In addition, sonography can exclude malrotation and may help the diagnosis of other diseases, such as annular pancreas and duodenal atresia. PMID:29049228

The efficiency of sonography in diagnosing volvulus in neonates with suspected intestinal malrotation.

PubMed

Zhang, Wenhua; Sun, Hongjun; Luo, Fangqiong

2017-10-01

This study is to prospectively evaluate the efficiency of sonography for volvulus diagnosis in neonates with clinically suspected intestinal malrotation.A total of 83 patients with suspected intestinal malrotation who underwent detailed abdominal sonography and upper gastrointestinal contrast study were included. Malrotation was characterized by inversion of the superior mesenteric artery (SMA) and superior mesenteric vein (SMV) in sonographic examination. The "whirlpool sign" of Color Doppler Sonography was recognized as a characteristic for malrotation with volvulus. The degrees of rotation of the SMV winding around SMA were also detected by sonography. Surgery was performed in patients with sonography diagnosed malrotation.A total of 39 patients were sonographically diagnosed as malrotation which was subsequently confirmed by surgery. The sensitivity and positive predictive value of the sonographic diagnosis were both 100% (39/39). The sensitivity, specificity and accuracy of "whirlpool sign" for the detection of midgut volvulus were 95.2% (20/21), 88.9% (16/18), and 92.3% (36/39), respectively. Greater degrees of rotation (equal or greater than 720°) showed higher risk (odds ratio, 5.0; P < .01) for intestinal necrosis occurrence.Sonography is more accurate in diagnosing suspected malrotation than upper gastrointestinal contrast study. Specific sonographic "whirlpool sign" related to volvulus may be used as a potential indicator for intestinal necrosis. In addition, sonography can exclude malrotation and may help the diagnosis of other diseases, such as annular pancreas and duodenal atresia.

Fusion Imaging: A Novel Staging Modality in Testis Cancer

PubMed Central

Sterbis, Joseph R.; Rice, Kevin R.; Javitt, Marcia C.; Schenkman, Noah S.; Brassell, Stephen A.

2010-01-01

Objective: Computed tomography and chest radiographs provide the standard imaging for staging, treatment, and surveillance of testicular germ cell neoplasms. Positron emission tomography has recently been utilized for staging, but is somewhat limited in its ability to provide anatomic localization. Fusion imaging combines the metabolic information provided by positron emission tomography with the anatomic precision of computed tomography. To the best of our knowledge, this represents the first study of the effectiveness using fusion imaging in evaluation of patients with testis cancer. Methods: A prospective study of 49 patients presenting to Walter Reed Army Medical Center with testicular cancer from 2003 to 2009 was performed. Fusion imaging was compared with conventional imaging, tumor markers, pathologic results, and clinical follow-up. Results: There were 14 true positives, 33 true negatives, 1 false positive, and 1 false negative. Sensitivity, specificity, positive predictive value, and negative predictive value were 93.3, 97.0, 93.3, and 97.0% respectively. In 11 patient scenarios, fusion imaging differed from conventional imaging. Utility was found in superior lesion detection compared to helical computed tomography due to anatomical/functional image co-registration, detection of micrometastasis in lymph nodes (pathologic nodes < 1cm), surveillance for recurrence post-chemotherapy, differentiating fibrosis from active disease in nodes < 2.5cm, and acting as a quality assurance measure to computed tomography alone. Conclusions: In addition to demonstrating a sensitivity and specificity comparable or superior to conventional imaging, fusion imaging shows promise in providing additive data that may assist in clinical decision-making. PMID:21103077

Fusion imaging: a novel staging modality in testis cancer.

PubMed

Sterbis, Joseph R; Rice, Kevin R; Javitt, Marcia C; Schenkman, Noah S; Brassell, Stephen A

2010-11-05

Computed tomography and chest radiographs provide the standard imaging for staging, treatment, and surveillance of testicular germ cell neoplasms. Positron emission tomography has recently been utilized for staging, but is somewhat limited in its ability to provide anatomic localization. Fusion imaging combines the metabolic information provided by positron emission tomography with the anatomic precision of computed tomography. To the best of our knowledge, this represents the first study of the effectiveness using fusion imaging in evaluation of patients with testis cancer. A prospective study of 49 patients presenting to Walter Reed Army Medical Center with testicular cancer from 2003 to 2009 was performed. Fusion imaging was compared with conventional imaging, tumor markers, pathologic results, and clinical follow-up. There were 14 true positives, 33 true negatives, 1 false positive, and 1 false negative. Sensitivity, specificity, positive predictive value, and negative predictive value were 93.3, 97.0, 93.3, and 97.0% respectively. In 11 patient scenarios, fusion imaging differed from conventional imaging. Utility was found in superior lesion detection compared to helical computed tomography due to anatomical/functional image co-registration, detection of micrometastasis in lymph nodes (pathologic nodes < 1cm), surveillance for recurrence post-chemotherapy, differentiating fibrosis from active disease in nodes < 2.5cm, and acting as a quality assurance measure to computed tomography alone. In addition to demonstrating a sensitivity and specificity comparable or superior to conventional imaging, fusion imaging shows promise in providing additive data that may assist in clinical decision-making.

Enhanced anger superiority effect in generalized anxiety disorder and panic disorder

PubMed Central

Ashwin, Chris; Holas, Pawel; Broadhurst, Shanna; Kokoszka, Andrzej; Georgiou, George A.; Fox, Elaine

2012-01-01

People are typically faster and more accurate to detect angry compared to happy faces, which is known as the anger superiority effect. Many cognitive models of anxiety suggest anxiety disorders involve attentional biases towards threat, although the nature of these biases remains unclear. The present study used a Face-in-the-Crowd task to investigate the anger superiority effect in a control group and patients diagnosed with either generalized anxiety disorder (GAD) or panic disorder (PD). The main finding was that both anxiety groups showed an enhanced anger superiority effect compared to controls, which is consistent with key theories of anxiety. Furthermore, both anxiety groups showed a differential pattern of enhanced bias towards threat depending on the crowd in the displays. The different attentional bias patterns between the GAD and PD groups may be related to the diverse symptoms in these disorders. These findings have implications for the diagnosis and treatment of anxiety. PMID:22196167

Differentiating benign from malignant solid breast masses: value of shear wave elastography according to lesion stiffness combined with greyscale ultrasound according to BI-RADS classification.

PubMed

Evans, A; Whelehan, P; Thomson, K; Brauer, K; Jordan, L; Purdie, C; McLean, D; Baker, L; Vinnicombe, S; Thompson, A

2012-07-10

The aim of this study was to assess the performance of shear wave elastography combined with BI-RADS classification of greyscale ultrasound images for benign/malignant differentiation in a large group of patients. One hundred and seventy-five consecutive patients with solid breast masses on routine ultrasonography undergoing percutaneous biopsy had the greyscale findings classified according to the American College of Radiology BI-RADS. The mean elasticity values from four shear wave images were obtained. For mean elasticity vs greyscale BI-RADS, the performance results against histology were sensitivity: 95% vs 95%, specificity: 77% vs 69%, Positive Predictive Value (PPV): 88% vs 84%, Negative Predictive Value (NPV): 90% vs 91%, and accuracy: 89% vs 86% (all P>0.05). The results for the combination (positive result from either modality counted as malignant) were sensitivity 100%, specificity 61%, PPV 82%, NPV 100%, and accuracy 86%. The combination of BI-RADS greyscale and shear wave elastography yielded superior sensitivity to BI-RADS alone (P=0.03) or shear wave alone (P=0.03). The NPV was superior in combination compared with either alone (BI-RADS P=0.01 and shear wave P=0.02). Together, BI-RADS assessment of greyscale ultrasound images and shear wave ultrasound elastography are extremely sensitive for detection of malignancy.

Differentiating benign from malignant solid breast masses: value of shear wave elastography according to lesion stiffness combined with greyscale ultrasound according to BI-RADS classification

PubMed Central

Evans, A; Whelehan, P; Thomson, K; Brauer, K; Jordan, L; Purdie, C; McLean, D; Baker, L; Vinnicombe, S; Thompson, A

2012-01-01

Background: The aim of this study was to assess the performance of shear wave elastography combined with BI-RADS classification of greyscale ultrasound images for benign/malignant differentiation in a large group of patients. Methods: One hundred and seventy-five consecutive patients with solid breast masses on routine ultrasonography undergoing percutaneous biopsy had the greyscale findings classified according to the American College of Radiology BI-RADS. The mean elasticity values from four shear wave images were obtained. Results: For mean elasticity vs greyscale BI-RADS, the performance results against histology were sensitivity: 95% vs 95%, specificity: 77% vs 69%, Positive Predictive Value (PPV): 88% vs 84%, Negative Predictive Value (NPV): 90% vs 91%, and accuracy: 89% vs 86% (all P>0.05). The results for the combination (positive result from either modality counted as malignant) were sensitivity 100%, specificity 61%, PPV 82%, NPV 100%, and accuracy 86%. The combination of BI-RADS greyscale and shear wave elastography yielded superior sensitivity to BI-RADS alone (P=0.03) or shear wave alone (P=0.03). The NPV was superior in combination compared with either alone (BI-RADS P=0.01 and shear wave P=0.02). Conclusion: Together, BI-RADS assessment of greyscale ultrasound images and shear wave ultrasound elastography are extremely sensitive for detection of malignancy. PMID:22691969

Retrospective study evaluating the performance of a first-trimester combined screening for trisomy 21 in an Italian unselected population

PubMed Central

Padula, Francesco; Cignini, Pietro; Giannarelli, Diana; Brizzi, Cristiana; Coco, Claudio; D’Emidio, Laura; Giorgio, Elsa; Giorlandino, Maurizio; Mangiafico, Lucia; Mastrandrea, Marialuisa; Milite, Vincenzo; Mobili, Luisa; Nanni, Cinzia; Raffio, Raffaella; Taramanni, Cinzia; Vigna, Roberto; Mesoraca, Alvaro; Bizzoco, Domenico; Gabrielli, Ivan; Di Giacomo, Gianluca; Barone, Maria Antonietta; Cima, Antonella; Giorlandino, Francesca Romana; Emili, Sabrina; Cupellaro, Marina; Giorlandino, Claudio

2014-01-01

Objectives to assess the performance of a combined first-trimester screening for trisomy 21 in an unselected Italian population referred to a specialized private center for prenatal medicine. Methods a retrospective validation of first-trimester screening algorithms [risk calculation based on maternal age and nuchal translucency (NT) alone, maternal age and serum parameters (free β-hCG and PAPP-A) alone and a combination of both] for fetal aneuploidies evaluated in an unselected Italian population at Artemisia Fetal-Maternal Medical Centre in Rome. All measurements were performed between 11+0 and 13+6 weeks of gestation, between April 2007 and December 2008. Results of 3,610 single fetuses included in the study, we had a complete follow-up on 2,984. Fourteen of 17 cases of trisomy 21 were detected when a cut-off of 1:300 was applied [detection rate (DR) 82.4%, 95% confidence interval (CI) 64.2–100; false-positive rate (FPR) 4.7%, 95% CI 3.9–5.4; false-negative rate (FNR) 17.6%, 95% CI 0–35.8%]. Conclusion in our study population the detection rate for trisomy 21, using the combined risk calculation based on maternal age, fetal NT, maternal PAPP-A and free β-hCG levels, was superior to the application of either parameter alone. The algorithm has been validated for first trimester screening in the Italian population. PMID:26266002

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ng, Sweet Ping, E-mail: sweet.ng@petermac.org; David, Steven; Alamgeer, Muhammad

Purpose: To assess the diagnostic performance of pretreatment {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography ({sup 18}F-FDG PET/CT) and its impact on radiation therapy treatment decisions in patients with locally advanced breast cancer (LABC). Methods and Materials: Patients with LABC with Eastern Cooperative Oncology Group performance status <2 and no contraindication to neoadjuvant chemotherapy, surgery, and adjuvant radiation therapy were enrolled on a prospective trial. All patients had pretreatment conventional imaging (CI) performed, including bilateral breast mammography and ultrasound, bone scan, and CT chest, abdomen, and pelvis scans performed. Informed consent was obtained before enrolment. Pretreatment whole-body {sup 18}F-FDG PET/CT scansmore » were performed on all patients, and results were compared with CI findings. Results: A total of 154 patients with LABC with no clinical or radiologic evidence of distant metastases on CI were enrolled. Median age was 49 years (range, 26-70 years). Imaging with PET/CT detected distant metastatic disease and/or locoregional disease not visualized on CI in 32 patients (20.8%). Distant metastatic disease was detected in 17 patients (11.0%): 6 had bony metastases, 5 had intrathoracic metastases (pulmonary/mediastinal), 2 had distant nodal metastases, 2 had liver metastases, 1 had pulmonary and bony metastases, and 1 had mediastinal and distant nodal metastases. Of the remaining 139 patients, nodal disease outside conventional radiation therapy fields was detected on PET/CT in 15 patients (10.8%), with involvement of ipsilateral internal mammary nodes in 13 and ipsilateral level 5 cervical nodes in 2. Conclusions: Imaging with PET/CT provides superior diagnostic and staging information in patients with LABC compared with CI, which has significant therapeutic implications with respect to radiation therapy management. Imaging with PET/CT should be considered in all patients undergoing primary staging for LABC.« less

Serum S100 calcium binding protein A4 improves the diagnostic accuracy of transient elastography for assessing liver fibrosis in hepatitis B.

PubMed

Yan, Li-Bo; Zhang, Qing-Bo; Zhu, Xia; He, Min; Tang, Hong

2018-02-01

The diagnostic performance of Fibroscan might be improved when combined with other serum fibrosis related markers. Previous study has demonstrated that S100A4 expression is associated with liver fibrosis in humans with hepatitis. This study aimed to clarify diagnostic accuracy of serum S100A4 levels for significant liver fibrosis in patients with chronic hepatitis B (CHB), and develop a combined algorithm of liver stiffness measurement (LSM) and S100A4 to predict significant liver fibrosis in CHB. One hundred and seventy-five CHB patients who had performed liver biopsy were consecutively included. We evaluated serum S100A4 levels, LSM values and other clinically-approved fibrosis scores. Serum S100A4 level was higher in CHB patients with significant fibrosis, compared to those without [199.58 (33.31-1971.96) vs. 107.15 (2.10-1038.94), P<0.001]. Using receiver-operating characteristic (ROC) analyses, the area under the curves (AUC), sensitivity, specificity and accuracy of S100A4 were found to be 0.749, 62.7%, 75.9% and 0.70 for significant fibrosis (≥Stage 2), respectively. Although not superior to LSM, these results were better than the fibrosis index based on the 4 factor (FIB-4) and the aspartate aminotransferase-to-platelet ratio index (APRI) for significant fibrosis detection. An algorithm consisting of S100A4 and LSM was derived. The AUC, sensitivity, specificity and accuracy of model based on serum S100A4 level and LSM were 0.866, 86.6%, 77.8% and 0.79 for significant fibrosis detection, superior to those based on LSM alone (0.834, 76.1%, 80.7% and 0.76, P=0.041). Serum S100A4 level was identified as a fibrosis marker of liver fibrosis in patients with CHB. Combining serum S100A4 with LSM improved the accuracy of transient elastography for hepatitis B significant fibrosis detection. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Using Information From Prior Satellite Scans to Improve Cloud Detection Near the Day-Night Terminator

NASA Technical Reports Server (NTRS)

Yost, Christopher R.; Minnis, Patrick; Trepte, Qing Z.; Palikonda, Rabindra; Ayers, Jeffrey K.; Spangenberg, Doulas A.

2012-01-01

With geostationary satellite data it is possible to have a continuous record of diurnal cycles of cloud properties for a large portion of the globe. Daytime cloud property retrieval algorithms are typically superior to nighttime algorithms because daytime methods utilize measurements of reflected solar radiation. However, reflected solar radiation is difficult to accurately model for high solar zenith angles where the amount of incident radiation is small. Clear and cloudy scenes can exhibit very small differences in reflected radiation and threshold-based cloud detection methods have more difficulty setting the proper thresholds for accurate cloud detection. Because top-of-atmosphere radiances are typically more accurately modeled outside the terminator region, information from previous scans can help guide cloud detection near the terminator. This paper presents an algorithm that uses cloud fraction and clear and cloudy infrared brightness temperatures from previous satellite scan times to improve the performance of a threshold-based cloud mask near the terminator. Comparisons of daytime, nighttime, and terminator cloud fraction derived from Geostationary Operational Environmental Satellite (GOES) radiance measurements show that the algorithm greatly reduces the number of false cloud detections and smoothes the transition from the daytime to the nighttime clod detection algorithm. Comparisons with the Geoscience Laser Altimeter System (GLAS) data show that using this algorithm decreases the number of false detections by approximately 20 percentage points.

Enantioselective determination of the organochlorine pesticide bromocyclen in spiked fish tissue using solid-phase microextraction coupled to gas chromatography with ECD and ICP-MS detection.

PubMed

Fidalgo-Used, Natalia; Montes-Bayón, Maria; Blanco-González, Elisa; Sanz-Medel, Alfredo

2008-05-15

A method for enantioselective determination of bromocyclen enantiomers in fish tissue has been developed. The enantiomers were resolved by capillary gas chromatography (GC) using a commercial chiral column (CP-Chirasil-Dex CB) and a temperature program from 50 degrees C (held for 1 min), raised to 140 degrees C at 40 degrees C min(-1) and then raised at 0.2 degrees C min(-1) to 155 degrees C. This enantioselective gas chromatographic separation was combined with a clean-up/enrichment procedure based on solid-phase microextraction (SPME). Under SPME optimized conditions, precision, linearity range and detection limits of the developed SPME-enantioselective GC procedure were evaluated and compared using two different detection systems: a classical electron-capture detection (ECD) and an element specific detection using inductively coupled plasma mass spectrometry (ICP-MS). The SPME-GC-ECD method exhibited an excellent sensitivity, with detection limits of 0.2 ng L(-1) for each enantiomer of bromocyclen. Although ICP-MS offered poorer detection limits (7 ng L(-1) as Br, equivalent to 36 ng L(-1) of each enantiomer) than conventional ECD detector, it proved to be clearly superior in terms of selectivity. The relative potential and performance of the two compared methods for real-life analysis has been illustrated by the determination of enantiomers of bromocyclen in spiked tissue extracts of trout.

Design of Passive Power Filter for Hybrid Series Active Power Filter using Estimation, Detection and Classification Method

NASA Astrophysics Data System (ADS)

Swain, Sushree Diptimayee; Ray, Pravat Kumar; Mohanty, K. B.

2016-06-01

This research paper discover the design of a shunt Passive Power Filter (PPF) in Hybrid Series Active Power Filter (HSAPF) that employs a novel analytic methodology which is superior than FFT analysis. This novel approach consists of the estimation, detection and classification of the signals. The proposed method is applied to estimate, detect and classify the power quality (PQ) disturbance such as harmonics. This proposed work deals with three methods: the harmonic detection through wavelet transform method, the harmonic estimation by Kalman Filter algorithm and harmonic classification by decision tree method. From different type of mother wavelets in wavelet transform method, the db8 is selected as suitable mother wavelet because of its potency on transient response and crouched oscillation at frequency domain. In harmonic compensation process, the detected harmonic is compensated through Hybrid Series Active Power Filter (HSAPF) based on Instantaneous Reactive Power Theory (IRPT). The efficacy of the proposed method is verified in MATLAB/SIMULINK domain and as well as with an experimental set up. The obtained results confirm the superiority of the proposed methodology than FFT analysis. This newly proposed PPF is used to make the conventional HSAPF more robust and stable.

Comparison of Four Sampling Gears in Detecting Invasive Invertebrates in the Duluth-Superior Harbor, Oral Presentation

EPA Science Inventory

It is important to conduct non-indigenous species assessments in areas at risk, such as ecosystems associated with Great Lakes harbors, both for the detection of new species and to determine the spread of existing ones. In addition to direct impacts on harbor ecosystems, addition...

Sprayable enzyme-activatable fluorescent probes: kinetic mapping using dynamic fluorescence imaging can help detecting tiny cancer foci (Conference Presentation)

NASA Astrophysics Data System (ADS)

Kobayashi, Hisataka

2017-02-01

Optical fluorescence-guided imaging is increasingly used to guide surgery and endoscopic procedures. Sprayable enzyme-activatable probes are particularly useful because of high target-to-background ratios that increase sensitivity for tiny cancer foci. However, green fluorescent activatable probes suffers from interference from autofluorescence found in biological tissue. Dynamic imaging followed by the kinetic analysis could be detected local enzyme activity and used to differentiate specific fluorescence arising from an activated probe in a tumor from autofluorescence in background tissues especially when low concentrations of the dye are applied to detect tiny cancer foci. Serial fluorescence imaging was performed using various concentrations of γ-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG) which was sprayed on the peritoneal surface with tiny implants of SHIN3-dsRed ovarian cancer tumors. Temporal differences in signal between specific green fluorescence in cancer foci and non-specific autofluorescence in background tissue was measured and processed into three kinetic maps reflecting maximum fluorescence signal (MF), wash-in rate (WIR), and area under the curve (AUC), respectively. Especially at lower concentrations, kinetic maps derived from dynamic fluorescence imaging were clearly superior to unprocessed images for detection small cancer foci.

Multichannel interictal spike activity detection using time-frequency entropy measure.

PubMed

Thanaraj, Palani; Parvathavarthini, B

2017-06-01

Localization of interictal spikes is an important clinical step in the pre-surgical assessment of pharmacoresistant epileptic patients. The manual selection of interictal spike periods is cumbersome and involves a considerable amount of analysis workload for the physician. The primary focus of this paper is to automate the detection of interictal spikes for clinical applications in epilepsy localization. The epilepsy localization procedure involves detection of spikes in a multichannel EEG epoch. Therefore, a multichannel Time-Frequency (T-F) entropy measure is proposed to extract features related to the interictal spike activity. Least squares support vector machine is used to train the proposed feature to classify the EEG epochs as either normal or interictal spike period. The proposed T-F entropy measure, when validated with epilepsy dataset of 15 patients, shows an interictal spike classification accuracy of 91.20%, sensitivity of 100% and specificity of 84.23%. Moreover, the area under the curve of Receiver Operating Characteristics plot of 0.9339 shows the superior classification performance of the proposed T-F entropy measure. The results of this paper show a good spike detection accuracy without any prior information about the spike morphology.

Gallium arsenide based surface plasmon resonance for glucose monitoring

NASA Astrophysics Data System (ADS)

Patil, Harshada; Sane, Vani; Sriram, G.; Indumathi, T. S; Sharan, Preeta

2015-07-01

The recent trends in the semiconductor and microwave industries has enabled the development of scalable microfabrication technology which produces a superior set of performance as against its counterparts. Surface Plasmon Resonance (SPR) based biosensors are a special class of optical sensors that become affected by electromagnetic waves. It is found that bio-molecular recognition element immobilized on the SPR sensor surface layer reveals a characteristic interaction with various sample solutions during the passage of light. The present work revolves around developing painless glucose monitoring systems using fluids containing glucose like saliva, urine, sweat or tears instead of blood samples. Non-invasive glucose monitoring has long been simulated using label free detection mechanisms and the same concept is adapted. In label-free detection, target molecules are not labeled or altered, and are detected in their natural forms. Label-free detection mechanisms involves the measurement of refractive index (RI) change induced by molecular interactions. These interactions relates the sample concentration or surface density, instead of total sample mass. After simulation it has been observed that the result obtained is highly accurate and sensitive. The structure used here is SPR sensor based on channel waveguide. The tools used for simulation are RSOFT FULLWAVE, MEEP and MATLAB etc.

Overlapping Community Detection based on Network Decomposition

NASA Astrophysics Data System (ADS)

Ding, Zhuanlian; Zhang, Xingyi; Sun, Dengdi; Luo, Bin

2016-04-01

Community detection in complex network has become a vital step to understand the structure and dynamics of networks in various fields. However, traditional node clustering and relatively new proposed link clustering methods have inherent drawbacks to discover overlapping communities. Node clustering is inadequate to capture the pervasive overlaps, while link clustering is often criticized due to the high computational cost and ambiguous definition of communities. So, overlapping community detection is still a formidable challenge. In this work, we propose a new overlapping community detection algorithm based on network decomposition, called NDOCD. Specifically, NDOCD iteratively splits the network by removing all links in derived link communities, which are identified by utilizing node clustering technique. The network decomposition contributes to reducing the computation time and noise link elimination conduces to improving the quality of obtained communities. Besides, we employ node clustering technique rather than link similarity measure to discover link communities, thus NDOCD avoids an ambiguous definition of community and becomes less time-consuming. We test our approach on both synthetic and real-world networks. Results demonstrate the superior performance of our approach both in computation time and accuracy compared to state-of-the-art algorithms.

Human rhinovirus C infections in pediatric hematology and oncology patients.

PubMed

Loria, Carolina; Domm, Jennifer A; Halasa, Natasha B; Heitman, Elizabeth; Miller, E Kathryn; Xu, Meng; Saville, Benjamin R; Frangoul, Haydar; Williams, John V

2015-02-01

Children with cancer and HSCT recipients are at high risk for common viral infections. We sought to define the viral etiology of ARI and identify risk factors. Nasal wash samples were collected from pediatric hematology-oncology patients and HSCT recipients with ARI during the 2003-2005 winter seasons. Real-time RT-PCR was performed to detect Flu A, influenza B, RSV, PIV 1-3, human MPV, and HRV. HRV specimens were sequenced and genotyped. Seventy-eight samples from 62 children were included. Viruses were detected in 31 of 78 samples (40%). HRV were detected most frequently, in 16 (52%) including five HRVC; followed by seven (22%) RSV, five (16%) Flu A, four (13%) MPV, and two (6%) PIV2. There was a trend toward higher risk of viral infection for children in day care. Only 8% of the study children had received influenza vaccine. HRV, including the recently discovered HRVC, are an important cause of infection in pediatric oncology and HSCT patients. Molecular testing is superior to conventional methods and should be standard of care, as HRV are not detected by conventional methods. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Of Uberfleas and Krakens: Detecting Trade-offs Using Mixed Models.

PubMed

Careau, Vincent; Wilson, Robbie S

2017-08-01

All animals experience performance trade-offs as they complete tasks such as capturing prey, defending territories, acquiring mates, and escaping predators. Why then, is it so hard to detect performance trade-offs at the whole-organismal level? Why do we sometimes even obtain positive correlations between two performance traits that are predicted to be negatively associated? Here we explore two plausible explanations. First, most analyses are based on individual maximal values (i.e., personal best), which could introduce a bias in the correlation estimates. Second, phenotypic correlations alone may be poor indicators of a trade-off when contrasting processes occur at the among- versus within-individual levels. One such scenario is the "big houses big cars" model developed in life-history theory to explain the existence of "uberfleas" that are superior in all regards (because they acquire more resources than others). We highlight that the exact opposite scenario might occur for performance trade-offs, where among-individual trade-offs may be masked by within-individual changes in physical condition. One of the best ways to test among these alternative scenarios is to collect repeated pairs of performance traits and analyze them using multivariate mixed models (MMMs). MMMs allow straightforward and simultaneous examination of trait correlations at the among- and within-individual levels. We use a simple simulation tool (SQuID package in R) to create a population of Krakens, a mythical giant squid-like sea creature whose morphology generates a performance trade-off between swimming speed and strength or ability to sink ships. The simulations showed that using individual maximum values introduces a bias that is particularly severe when individuals differ in the number of repeated samples (ntrial). Finally, we show how MMMs can help detect performance (or any other type of) trade-offs and offer additional insights (e.g., help detect plasticity integration). We hope researchers will adopt MMMs when exploring trade-offs in whole-animal performances. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Effect of respiratory muscle training on exercise performance in healthy individuals: a systematic review and meta-analysis.

PubMed

Illi, Sabine K; Held, Ulrike; Frank, Irène; Spengler, Christina M

2012-08-01

Two distinct types of specific respiratory muscle training (RMT), i.e. respiratory muscle strength (resistive/threshold) and endurance (hyperpnoea) training, have been established to improve the endurance performance of healthy individuals. We performed a systematic review and meta-analysis in order to determine the factors that affect the change in endurance performance after RMT in healthy subjects. A computerized search was performed without language restriction in MEDLINE, EMBASE and CINAHL and references of original studies and reviews were searched for further relevant studies. RMT studies with healthy individuals assessing changes in endurance exercise performance by maximal tests (constant load, time trial, intermittent incremental, conventional [non-intermittent] incremental) were screened and abstracted by two independent investigators. A multiple linear regression model was used to identify effects of subjects' fitness, type of RMT (inspiratory or combined inspiratory/expiratory muscle strength training, respiratory muscle endurance training), type of exercise test, test duration and type of sport (rowing, running, swimming, cycling) on changes in performance after RMT. In addition, a meta-analysis was performed to determine the effect of RMT on endurance performance in those studies providing the necessary data. The multiple linear regression analysis including 46 original studies revealed that less fit subjects benefit more from RMT than highly trained athletes (6.0% per 10 mL · kg⁻¹ · min⁻¹ decrease in maximal oxygen uptake, 95% confidence interval [CI] 1.8, 10.2%; p = 0.005) and that improvements do not differ significantly between inspiratory muscle strength and respiratory muscle endurance training (p = 0.208), while combined inspiratory and expiratory muscle strength training seems to be superior in improving performance, although based on only 6 studies (+12.8% compared with inspiratory muscle strength training, 95% CI 3.6, 22.0%; p = 0.006). Furthermore, constant load tests (+16%, 95% CI 10.2, 22.9%) and intermittent incremental tests (+18.5%, 95% CI 10.8, 26.3%) detect changes in endurance performance better than conventional incremental tests (both p < 0.001) with no difference between time trials and conventional incremental tests (p = 0.286). With increasing test duration, improvements in performance are greater (+0.4% per minute test duration, 95% CI 0.1, 0.6%; p = 0.011) and the type of sport does not influence the magnitude of improvements (all p > 0.05). The meta-analysis, performed on eight controlled trials revealed a significant improvement in performance after RMT, which was detected by constant load tests, time trials and intermittent incremental tests, but not by conventional incremental tests. RMT improves endurance exercise performance in healthy individuals with greater improvements in less fit individuals and in sports of longer durations. The two most common types of RMT (inspiratory muscle strength and respiratory muscle endurance training) do not differ significantly in their effect, while combined inspiratory/expiratory strength training might be superior. Improvements are similar between different types of sports. Changes in performance can be detected by constant load tests, time trials and intermittent incremental tests only. Thus, all types of RMT can be used to improve exercise performance in healthy subjects but care must be taken regarding the test used to investigate the improvements.

F-18 FDG PET, CT, and MRI for detecting the malignant potential in patients with gastrointestinal stromal tumors: A protocol for a network meta-analysis of diagnostic test accuracy.

PubMed

Wei, Kongyuan; Pan, Bei; Yang, Huan; Lu, Cuncun; Ge, Long; Cao, Nong

2018-04-01

Gastrointestinal stromal tumor (GIST) is a rare cancer in gastrointestinal carcinomas and has been widely known as a curable disease among all the digestive tumors. However, early detection of malignant potential in patients with GIST has still been a huge challenge all around the world. CT, MRI, and F-18 FDG PET are all considered as good tests for diagnosing malignant GIST efficiently, but no recommended suggestions presents which test among the 3 is the prior one in detecting the malignant potential of GIST. We perform this study to assess the accuracy between CT, MRI, and F-18 FDG PET through network meta-analysis method, and to rank these tests. PubMed, EMBASE.com, CNKI, and CBM databases will be searched without search date and language restrictions. We will include diagnostic tests which assessed the accuracy of CT, MRI, and F-18 FDG PET in detecting the malignant potential of GIST. The risk of bias in each study will be independently assessed as low, moderate, or high using criteria adapted from Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Meta-analysis will be performed using STATA 12.0 and R 3.4.1 software. The competing diagnostic tests will be ranked by a superiority index. This study is ongoing, and will be submitted to a peer-reviewed journal for publication. This study will provide a comprehensive evidence summary of CT, MRI, and F-18 FDG PET in detecting the malignant potential of GIST.

Automated detection of tuberculosis on sputum smeared slides using stepwise classification

NASA Astrophysics Data System (ADS)

Divekar, Ajay; Pangilinan, Corina; Coetzee, Gerrit; Sondh, Tarlochan; Lure, Fleming Y. M.; Kennedy, Sean

2012-03-01

Routine visual slide screening for identification of tuberculosis (TB) bacilli in stained sputum slides under microscope system is a tedious labor-intensive task and can miss up to 50% of TB. Based on the Shannon cofactor expansion on Boolean function for classification, a stepwise classification (SWC) algorithm is developed to remove different types of false positives, one type at a time, and to increase the detection of TB bacilli at different concentrations. Both bacilli and non-bacilli objects are first analyzed and classified into several different categories including scanty positive, high concentration positive, and several non-bacilli categories: small bright objects, beaded, dim elongated objects, etc. The morphological and contrast features are extracted based on aprior clinical knowledge. The SWC is composed of several individual classifiers. Individual classifier to increase the bacilli counts utilizes an adaptive algorithm based on a microbiologist's statistical heuristic decision process. Individual classifier to reduce false positive is developed through minimization from a binary decision tree to classify different types of true and false positive based on feature vectors. Finally, the detection algorithm is was tested on 102 independent confirmed negative and 74 positive cases. A multi-class task analysis shows high accordance rate for negative, scanty, and high-concentration as 88.24%, 56.00%, and 97.96%, respectively. A binary-class task analysis using a receiver operating characteristics method with the area under the curve (Az) is also utilized to analyze the performance of this detection algorithm, showing the superior detection performance on the high-concentration cases (Az=0.913) and cases mixed with high-concentration and scanty cases (Az=0.878).

A Hybrid Approach for CpG Island Detection in the Human Genome.

PubMed

Yang, Cheng-Hong; Lin, Yu-Da; Chiang, Yi-Cheng; Chuang, Li-Yeh

2016-01-01

CpG islands have been demonstrated to influence local chromatin structures and simplify the regulation of gene activity. However, the accurate and rapid determination of CpG islands for whole DNA sequences remains experimentally and computationally challenging. A novel procedure is proposed to detect CpG islands by combining clustering technology with the sliding-window method (PSO-based). Clustering technology is used to detect the locations of all possible CpG islands and process the data, thus effectively obviating the need for the extensive and unnecessary processing of DNA fragments, and thus improving the efficiency of sliding-window based particle swarm optimization (PSO) search. This proposed approach, named ClusterPSO, provides versatile and highly-sensitive detection of CpG islands in the human genome. In addition, the detection efficiency of ClusterPSO is compared with eight CpG island detection methods in the human genome. Comparison of the detection efficiency for the CpG islands in human genome, including sensitivity, specificity, accuracy, performance coefficient (PC), and correlation coefficient (CC), ClusterPSO revealed superior detection ability among all of the test methods. Moreover, the combination of clustering technology and PSO method can successfully overcome their respective drawbacks while maintaining their advantages. Thus, clustering technology could be hybridized with the optimization algorithm method to optimize CpG island detection. The prediction accuracy of ClusterPSO was quite high, indicating the combination of CpGcluster and PSO has several advantages over CpGcluster and PSO alone. In addition, ClusterPSO significantly reduced implementation time.

Information Theoretic Extraction of EEG Features for Monitoring Subject Attention

NASA Technical Reports Server (NTRS)

Principe, Jose C.

2000-01-01

The goal of this project was to test the applicability of information theoretic learning (feasibility study) to develop new brain computer interfaces (BCI). The difficulty to BCI comes from several aspects: (1) the effective data collection of signals related to cognition; (2) the preprocessing of these signals to extract the relevant information; (3) the pattern recognition methodology to detect reliably the signals related to cognitive states. We only addressed the two last aspects in this research. We started by evaluating an information theoretic measure of distance (Bhattacharyya distance) for BCI performance with good predictive results. We also compared several features to detect the presence of event related desynchronization (ERD) and synchronization (ERS), and concluded that at least for now the bandpass filtering is the best compromise between simplicity and performance. Finally, we implemented several classifiers for temporal - pattern recognition. We found out that the performance of temporal classifiers is superior to static classifiers but not by much. We conclude by stating that the future of BCI should be found in alternate approaches to sense, collect and process the signals created by populations of neurons. Towards this goal, cross-disciplinary teams of neuroscientists and engineers should be funded to approach BCIs from a much more principled view point.

Amorphization of cobalt monoxide nanocrystals and related explosive gas sensing applications.

PubMed

Li, L H; Xiao, J; Yang, G W

2015-10-16

Amorphous nanomaterials have attracted attention due to their excellent performances, highly comparable to their crystalline counterparts. Sensor materials with amorphous phases are usually evaluated to be unsuitable for sensors because of poor performance. As a matter of fact, amorphous nanomaterials have rather unique sensor behaviors. Here, we report the amorphousization of cobalt monoxide (CoO) nanocrystals driven by a unique process involved in laser ablation in liquid (LAL). We also established that a fast and nonequilibrium process created by LAL results in the amorphousization of nanocrystals. The as-prepared amorphous CoO (a-CoO) nanoflakes possess a high aspect ratio, which showed good sensing of explosive gases. The fabricated gas sensor can detect CO and H2 at levels as low as 5 and 10 ppm, respectively, at 100 °C. The performance characteristics of this sensor, including high sensitivity, low working temperature, and low detection limit, are superior to those of sensors made with crystalline phase oxides. Meanwhile, a temperature-dependent p-n transition was observed in the sensor's response to CO, suggesting that the sensing properties can be tailored by changing the carrier type, thus tuning the selectivity of sensors to different gases. These findings demonstrate the potential applications of amorphous nanomaterials as gas sensor components.

Micro computed tomography features of laryngeal fractures in a case of fatal manual strangulation.

PubMed

Fais, Paolo; Giraudo, Chiara; Viero, Alessia; Miotto, Diego; Bortolotti, Federica; Tagliaro, Franco; Montisci, Massimo; Cecchetto, Giovanni

2016-01-01

Cases of subtle fatal neck compression are often complicated by the lack of specificity of the post-mortem signs of asphyxia and by the lack of clear signs of neck compression. Herein we present a forensic case of a 45-year-old schizophrenic patient found on the floor of the bedroom of a psychiatric ward in cardiopulmonary arrest and who died after two days in a vegetative state. The deposition of the roommate of the deceased, who claimed responsibility for the killing of the victim by neck compression, was considered unreliable by the prosecutor. Autopsy, toxicological analyses, and multi-slice computed tomography (MSCT), micro computed tomography (micro-CT) and histology of the larynx complex were performed. Particularly, micro-CT analysis of the thyroid cartilage revealed the bilateral presence of ossified triticeous cartilages and the complete fragmentation of the right superior horn of the thyroid, but it additionally demonstrated a fracture on the contralateral superior horns, which was not clearly diagnosable at MSCT. On the basis of the evidence of intracartilaginous laryngeal hemorrhages and bilateral microfracture at the base of the superior horns of the larynx, the death was classified as a case of asphyxia due to manual strangulation. Micro-CT was confirmed as a useful tool in cases of subtle fatal neck compression, for the detection of minute laryngeal cartilage fractures, especially in complex cases with equivocal findings on MSCT. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Dual tracer functional imaging of gastroenteropancreatic neuroendocrine tumors using 68Ga-DOTA-NOC PET-CT and 18F-FDG PET-CT: competitive or complimentary?

PubMed

Naswa, Niraj; Sharma, Punit; Gupta, Santosh Kumar; Karunanithi, Sellam; Reddy, Rama Mohan; Patnecha, Manish; Lata, Sneh; Kumar, Rakesh; Malhotra, Arun; Bal, Chandrasekhar

2014-01-01

This study aimed to compare the diagnostic performance of Ga-DOTANOC PET/CT with F-FDG PET/CT in the patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Data of 51 patients with definite histological diagnosis of GEP-NET who underwent both Ga-DOTA-NOC PET-CT and F-FDG PET-CT within a span of 15 days were selected for this retrospective analysis. Sensitivity, specificity, and predictive values were calculated for Ga-DOTA-NOC PET-CT and F-FDG PET-CT, and results were compared both on patientwise and regionwise analysis. Ga-DOTA-NOC PET-CT is superior to F-FDG PET-CT on patientwise analysis (P < 0.0001). On regionwise analysis, Ga-DOTA-NOC PET-CT is superior to F-FDG PET-CT only for lymph node metastases (P < 0.003). Although Ga-DOTA-NOC PET-CT detected more liver and skeletal lesions compared with F-FDG PET-CT, the difference was not statistically significant. In addition, the results of combined imaging helped in selecting candidates who would undergo the appropriate mode of treatment, whether octreotide therapy or conventional chemotherapy Ga-DOTA-NOC PET-CT seems to be superior to F-FDG PET-CT for imaging GEP-NETs. However, their role seems to be complementary because combination of Ga-DOTA-NOC PET-CT and F-FDG PET-CT in such patients helps demonstrate the total disease burden and segregate them to proper therapeutic groups.

The mental simulation of state/psychological verbs in the adolescent brain: An fMRI study.

PubMed

Tomasino, Barbara; Nobile, Maria; Re, Marta; Bellina, Monica; Garzitto, Marco; Arrigoni, Filippo; Molteni, Massimo; Fabbro, Franco; Brambilla, Paolo

2018-06-01

This fMRI study investigated mental simulation of state/psychological and action verbs during adolescence. Sixteen healthy subjects silently read verbs describing a motor scene or not (STIMULUS: motor, state/psychological verbs) and they were explicitly asked to imagine the situation or they performed letter detection preventing them from using simulation (TASK: imagery vs. letter detection). A significant task by stimuli interaction showed that imagery of state/psychological verbs, as compared to action stimuli (controlled by the letter detection) selectively increased activation in the right supramarginal gyrus/rolandic operculum and in the right insula, and decreased activation in the right intraparietal sulcus. We compared these data to those from a group of older participants (Tomasino et al. 2014a). Activation in the left supramarginal gyrus decreased for the latter group (as compared to the present group) for imagery of state/psychological verbs. By contrast, activation in the right superior frontal gyrus decreased for the former group (as compared to the older group) for imagery of state/psychological verbs. Copyright © 2018 Elsevier Inc. All rights reserved.

[Establishment of Automation System for Detection of Alcohol in Blood].

PubMed

Tian, L L; Shen, Lei; Xue, J F; Liu, M M; Liang, L J

2017-02-01

To establish an automation system for detection of alcohol content in blood. The determination was performed by automated workstation of extraction-headspace gas chromatography （HS-GC）. The blood collection with negative pressure, sealing time of headspace bottle and sample needle were checked and optimized in the abstraction of automation system. The automatic sampling was compared with the manual sampling. The quantitative data obtained by the automated workstation of extraction-HS-GC for alcohol was stable. The relative differences of two parallel samples were less than 5%. The automated extraction was superior to the manual extraction. A good linear relationship was obtained at the alcohol concentration range of 0.1-3.0 mg/mL （ r ≥0.999） with good repeatability. The method is simple and quick, with more standard experiment process and accurate experimental data. It eliminates the error from the experimenter and has good repeatability, which can be applied to the qualitative and quantitative detections of alcohol in blood. Copyright© by the Editorial Department of Journal of Forensic Medicine

Bacterial community analysis of swine manure treated with autothermal thermophilic aerobic digestion.

PubMed

Han, Il; Congeevaram, Shankar; Ki, Dong-Won; Oh, Byoung-Taek; Park, Joonhong

2011-02-01

Due to the environmental problems associated with disposal of livestock sludge, many stabilization studies emphasizing on the sludge volume reduction were performed. However, little is known about the microbial risk present in sludge and its stabilized products. This study microbiologically explored the effects of anaerobic lagoon fermentation (ALF) and autothermal thermophilic aerobic digestion (ATAD) on pathogen-related risk of raw swine manure by using culture-independent 16S rDNA cloning and sequencing methods. In raw swine manure, clones closely related to pathogens such as Dialister pneumosintes, Erysipelothrix rhusiopathiae, Succinivibrioan dextrinosolvens, and Schineria sp. were detected. Meanwhile, in the mesophilic ALF-treated swine manure, bacterial community clones closely related to pathogens such as Schineria sp. and Succinivibrio dextrinosolvens were still detected. Interestingly, the ATAD treatment resulted in no detection of clones closely related to pathogens in the stabilized thermophilic bacterial community, with the predominance of novel Clostridia class populations. These findings support the superiority of ATAD in selectively reducing potential human and animal pathogens compared to ALF, which is a typical manure stabilization method used in livestock farms.

Micropatterned Pyramidal Ionic Gels for Sensing Broad-Range Pressures with High Sensitivity.

PubMed

Cho, Sung Hwan; Lee, Seung Won; Yu, Seunggun; Kim, Hyeohn; Chang, Sooho; Kang, Donyoung; Hwang, Ihn; Kang, Han Sol; Jeong, Beomjin; Kim, Eui Hyuk; Cho, Suk Man; Kim, Kang Lib; Lee, Hyungsuk; Shim, Wooyoung; Park, Cheolmin

2017-03-22

The development of pressure sensors that are effective over a broad range of pressures is crucial for the future development of electronic skin applicable to the detection of a wide pressure range from acoustic wave to dynamic human motion. Here, we present flexible capacitive pressure sensors that incorporate micropatterned pyramidal ionic gels to enable ultrasensitive pressure detection. Our devices show superior pressure-sensing performance, with a broad sensing range from a few pascals up to 50 kPa, with fast response times of <20 ms and a low operating voltage of 0.25 V. Since high-dielectric-constant ionic gels were employed as constituent sensing materials, an unprecedented sensitivity of 41 kPa -1 in the low-pressure regime of <400 Pa could be realized in the context of a metal-insulator-metal platform. This broad-range capacitive pressure sensor allows for the efficient detection of pressure from a variety of sources, including sound waves, a lightweight object, jugular venous pulses, radial artery pulses, and human finger touch. This platform offers a simple, robust approach to low-cost, scalable device design, enabling practical applications of electronic skin.

A Novel Detection Model and Its Optimal Features to Classify Falls from Low- and High-Acceleration Activities of Daily Life Using an Insole Sensor System

PubMed Central

Cates, Benjamin; Sim, Taeyong; Heo, Hyun Mu; Kim, Bori; Kim, Hyunggun; Mun, Joung Hwan

2018-01-01

In order to overcome the current limitations in current threshold-based and machine learning-based fall detectors, an insole system and novel fall classification model were created. Because high-acceleration activities have a high risk for falls, and because of the potential damage that is associated with falls during high-acceleration activities, four low-acceleration activities, four high-acceleration activities, and eight types of high-acceleration falls were performed by twenty young male subjects. Encompassing a total of 800 falls and 320 min of activities of daily life (ADLs), the created Support Vector Machine model’s Leave-One-Out cross-validation provides a fall detection sensitivity (0.996), specificity (1.000), and accuracy (0.999). These classification results are similar or superior to other fall detection models in the literature, while also including high-acceleration ADLs to challenge the classification model, and simultaneously reducing the burden that is associated with wearable sensors and increasing user comfort by inserting the insole system into the shoe. PMID:29673165

Damage detection in composite panels based on mode-converted Lamb waves sensed using 3D laser scanning vibrometer

NASA Astrophysics Data System (ADS)

Pieczonka, Łukasz; Ambroziński, Łukasz; Staszewski, Wiesław J.; Barnoncel, David; Pérès, Patrick

2017-12-01

This paper introduces damage identification approach based on guided ultrasonic waves and 3D laser Doppler vibrometry. The method is based on the fact that the symmetric and antisymmetric Lamb wave modes differ in amplitude of the in-plane and out-of-plane vibrations. Moreover, the modes differ also in group velocities and normally they are well separated in time. For a given time window both modes can occur simultaneously only close to the wave source or to a defect that leads to mode conversion. By making the comparison between the in-plane and out-of-plane wave vector components the detection of mode conversion is possible, allowing for superior and reliable damage detection. Experimental verification of the proposed damage identification procedure is performed on fuel tank elements of Reusable Launch Vehicles designed for space exploration. Lamb waves are excited using low-profile, surface-bonded piezoceramic transducers and 3D scanning laser Doppler vibrometer is used to characterize the Lamb wave propagation field. The paper presents theoretical background of the proposed damage identification technique as well as experimental arrangements and results.

Qualitative and quantitative analysis of hyaluronan oligosaccharides with high performance thin layer chromatography using reagent-free derivatization on amino-modified silica and electrospray ionization-quadrupole time-of-flight mass spectrometry coupling on normal phase.

PubMed

Rothenhöfer, Martin; Scherübl, Rosmarie; Bernhardt, Günther; Heilmann, Jörg; Buschauer, Armin

2012-07-27

Purified oligomers of hyalobiuronic acid are indispensable tools to elucidate the physiological and pathophysiological role of hyaluronan degradation by various hyaluronidase isoenzymes. Therefore, we established and validated a novel sensitive, convenient, rapid, and cost-effective high performance thin layer chromatography (HPTLC) method for the qualitative and quantitative analysis of small saturated hyaluronan oligosaccharides consisting of 2-4 hyalobiuronic acid moieties. The use of amino-modified silica as stationary phase allows a simple reagent-free in situ derivatization by heating, resulting in a very low limit of detection (7-19 pmol per band, depending on the analyzed saturated oligosaccharide). By this derivatization procedure for the first time densitometric quantification of the analytes could be performed by HPTLC. The validated method showed a quantification limit of 37-71 pmol per band and was proven to be superior in comparison to conventional detection of hyaluronan oligosaccharides. The analytes were identified by hyphenation of normal phase planar chromatography to mass spectrometry (TLC-MS) using electrospray ionization. As an alternative to sequential techniques such as high performance liquid chromatography (HPLC) and capillary electrophoresis (CE), the validated HPTLC quantification method can easily be automated and is applicable to the analysis of multiple samples in parallel. Copyright © 2012 Elsevier B.V. All rights reserved.

Improvement of retinal blood vessel detection using morphological component analysis.

PubMed

Imani, Elaheh; Javidi, Malihe; Pourreza, Hamid-Reza

2015-03-01

Detection and quantitative measurement of variations in the retinal blood vessels can help diagnose several diseases including diabetic retinopathy. Intrinsic characteristics of abnormal retinal images make blood vessel detection difficult. The major problem with traditional vessel segmentation algorithms is producing false positive vessels in the presence of diabetic retinopathy lesions. To overcome this problem, a novel scheme for extracting retinal blood vessels based on morphological component analysis (MCA) algorithm is presented in this paper. MCA was developed based on sparse representation of signals. This algorithm assumes that each signal is a linear combination of several morphologically distinct components. In the proposed method, the MCA algorithm with appropriate transforms is adopted to separate vessels and lesions from each other. Afterwards, the Morlet Wavelet Transform is applied to enhance the retinal vessels. The final vessel map is obtained by adaptive thresholding. The performance of the proposed method is measured on the publicly available DRIVE and STARE datasets and compared with several state-of-the-art methods. An accuracy of 0.9523 and 0.9590 has been respectively achieved on the DRIVE and STARE datasets, which are not only greater than most methods, but are also superior to the second human observer's performance. The results show that the proposed method can achieve improved detection in abnormal retinal images and decrease false positive vessels in pathological regions compared to other methods. Also, the robustness of the method in the presence of noise is shown via experimental result. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Unique blood culture for diagnosis of bloodstream infections in emergency departments: a prospective multicentre study.

PubMed

Dargère, S; Parienti, J-J; Roupie, E; Gancel, P-E; Wiel, E; Smaiti, N; Loiez, C; Joly, L-M; Lemée, L; Pestel-Caron, M; du Cheyron, D; Verdon, R; Leclercq, R; Cattoir, V

2014-11-01

Detection of microorganisms by blood cultures (BCs) is essential in managing patients with bacteraemia. Rather than the number of punctures, the volume of blood drawn is considered paramount in efficient and reliable detection of microorganisms. We performed a 1-year prospective multicentre study in adult emergency departments of three French university hospitals comparing two methods for BCs: a unique blood culture (UBC) collecting a large volume of blood (40 mL) and the standard method of multiple blood cultures (MBC). The performances of both methods for bacterial contamination and efficient microbial detection were compared, each patient serving as his own control. Amongst the 2314 patients included, three hundred were positive for pathogens (n=245) or contaminants (n=55). Out of the 245 patients, 11 were positive for pathogens by UBC but negative by MBC and seven negative by UBC but positive by MBC (p 0.480). In the subgroup of 137 patients with only two BCs, UBC was superior to MBC (p 0.044). Seven and 17 patients had contaminated BCs by UBC and MBC only, respectively (p 0.062). Considering the sums of pathogens missed and contaminants, UBC significantly outperformed MBC (p 0.045). Considering the complete picture of cost savings, efficient detection of microorganisms and decrease in contaminations, UBC offers an interesting alternative to MBC. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.

3D fluid-attenuated inversion recovery imaging: reduced CSF artifacts and enhanced sensitivity and specificity for subarachnoid hemorrhage.

PubMed

Lummel, N; Schoepf, V; Burke, M; Brueckmann, H; Linn, J

2011-12-01

FLAIR images are highly sensitive for SAH. However, CSF flow artifacts caused by conventional FLAIR can produce false-positive results. Here, we compare 3D and 3D FLAIR sequences, focusing on their potential for containing these artifacts and their sensitivity and specificity for detection of SAHs. We evaluated the following 4 FLAIR sequences: 1) 2D FLAIR at 1.5T, 2) 2D FLAIR, 3) 2D PROPELLER-FLAIR, and 4) 3D Cube-FLAIR at 3T. All sequences were performed in 5 healthy volunteers; sequences 2 and 4 were also performed under routine conditions in 10 patients with focal epilepsy and in 10 patients with SAH. Two neuroradiologists independently conducted the analysis. The presence of flow artifacts in the ventricles and cisterns of healthy volunteers and patients with epilepsy was evaluated and scored on a 4-point scale. Mean values were calculated and compared by using paired t tests. Sensitivity and specificity for SAH detection in sequences 2 and 4 were determined. Cube-FLAIR showed almost no CSF artifacts in the volunteers and the patients with epilepsy; therefore, it was superior to any other FLAIR (P < .001). Sensitivity and specificity of SAH detection by 3T FLAIR were 58.3% and 89.4%, respectively, whereas Cube-FLAIR had a sensitivity of 95% and a specificity of 100%. Cube-FLAIR allows FLAIR imaging with almost no CSF artifacts and is, thus, particularly useful for SAH detection.

Pseudoaneurysm of the superior lateral genicular artery: case report of a rare complication after total knee arthroplasty

PubMed Central

2013-01-01

Background Pseudoaneurysm of superior lateral genicular artery following total knee arthroplasty is a rare complication and has been reported following lateral release performed for eversion of patella in a knee with tight lateral structures. Case presentation This report describes a case of pseudo aneurysm of superior lateral geniculate artery that developed after primary Total knee arthroplasty for a stiff knee in a 68 year old patient. Patient presented with pain and rapidly increasing swelling in early post operative period. Diagnosis was made on duplex ultrasound and confirmed by angiography. Angiographic coil embolisation of the pseudoaneurysm was performed. Since no lateral release was performed in this case, the probable mechanism was shear injury to the vessel. Conclusion Pseudoaneurysm of superior lateral genicular artery can occur in absence of lateral release by shear injury to an atherosclerotic vessel. Angiographic coil embolisation appears to be the best method for treating such post arthroplasty pseudoaneurysm because of less chance of infection, non interference with rehabilitation and diagnosis and treatment during same procedure. PMID:23687974

Niche harmony search algorithm for detecting complex disease associated high-order SNP combinations.

PubMed

Tuo, Shouheng; Zhang, Junying; Yuan, Xiguo; He, Zongzhen; Liu, Yajun; Liu, Zhaowen

2017-09-14

Genome-wide association study is especially challenging in detecting high-order disease-causing models due to model diversity, possible low or even no marginal effect of the model, and extraordinary search and computations. In this paper, we propose a niche harmony search algorithm where joint entropy is utilized as a heuristic factor to guide the search for low or no marginal effect model, and two computationally lightweight scores are selected to evaluate and adapt to diverse of disease models. In order to obtain all possible suspected pathogenic models, niche technique merges with HS, which serves as a taboo region to avoid HS trapping into local search. From the resultant set of candidate SNP-combinations, we use G-test statistic for testing true positives. Experiments were performed on twenty typical simulation datasets in which 12 models are with marginal effect and eight ones are with no marginal effect. Our results indicate that the proposed algorithm has very high detection power for searching suspected disease models in the first stage and it is superior to some typical existing approaches in both detection power and CPU runtime for all these datasets. Application to age-related macular degeneration (AMD) demonstrates our method is promising in detecting high-order disease-causing models.

Functional magnetic resonance imaging activation detection: fuzzy cluster analysis in wavelet and multiwavelet domains.

PubMed

Jahanian, Hesamoddin; Soltanian-Zadeh, Hamid; Hossein-Zadeh, Gholam-Ali

2005-09-01

To present novel feature spaces, based on multiscale decompositions obtained by scalar wavelet and multiwavelet transforms, to remedy problems associated with high dimension of functional magnetic resonance imaging (fMRI) time series (when they are used directly in clustering algorithms) and their poor signal-to-noise ratio (SNR) that limits accurate classification of fMRI time series according to their activation contents. Using randomization, the proposed method finds wavelet/multiwavelet coefficients that represent the activation content of fMRI time series and combines them to define new feature spaces. Using simulated and experimental fMRI data sets, the proposed feature spaces are compared to the cross-correlation (CC) feature space and their performances are evaluated. In these studies, the false positive detection rate is controlled using randomization. To compare different methods, several points of the receiver operating characteristics (ROC) curves, using simulated data, are estimated and compared. The proposed features suppress the effects of confounding signals and improve activation detection sensitivity. Experimental results show improved sensitivity and robustness of the proposed method compared to the conventional CC analysis. More accurate and sensitive activation detection can be achieved using the proposed feature spaces compared to CC feature space. Multiwavelet features show superior detection sensitivity compared to the scalar wavelet features. (c) 2005 Wiley-Liss, Inc.

Automatic detection of Martian dark slope streaks by machine learning using HiRISE images

NASA Astrophysics Data System (ADS)

Wang, Yexin; Di, Kaichang; Xin, Xin; Wan, Wenhui

2017-07-01

Dark slope streaks (DSSs) on the Martian surface are one of the active geologic features that can be observed on Mars nowadays. The detection of DSS is a prerequisite for studying its appearance, morphology, and distribution to reveal its underlying geological mechanisms. In addition, increasingly massive amounts of Mars high resolution data are now available. Hence, an automatic detection method for locating DSSs is highly desirable. In this research, we present an automatic DSS detection method by combining interest region extraction and machine learning techniques. The interest region extraction combines gradient and regional grayscale information. Moreover, a novel recognition strategy is proposed that takes the normalized minimum bounding rectangles (MBRs) of the extracted regions to calculate the Local Binary Pattern (LBP) feature and train a DSS classifier using the Adaboost machine learning algorithm. Comparative experiments using five different feature descriptors and three different machine learning algorithms show the superiority of the proposed method. Experimental results utilizing 888 extracted region samples from 28 HiRISE images show that the overall detection accuracy of our proposed method is 92.4%, with a true positive rate of 79.1% and false positive rate of 3.7%, which in particular indicates great performance of the method at eliminating non-DSS regions.

Sensitive electrochemical sensors for simultaneous determination of ascorbic acid, dopamine, and uric acid based on Au@Pd-reduced graphene oxide nanocomposites

NASA Astrophysics Data System (ADS)

Jiang, Jingjing; Du, Xuezhong

2014-09-01

Sensitive electrochemical sensors were fabricated with reduced graphene oxide-supported Au@Pd (Au@Pd-RGO) nanocomposites by one-step synthesis for individual and simultaneous determination of ascorbic acid (AA), dopamine (DA), and uric acid (UA) with low detection limits and wide concentration ranges. From the Au@Pd-RGO-modified electrodes, well-separated oxidation peaks and enhanced peak currents of AA, DA, and UA were observed owing to the superior conductivity of RGO and the excellent catalytic activity of Au@Pd nanoparticles. For individual detection, the linear responses of AA, DA, and UA were in the concentration ranges of 0.1-1000, 0.01-100, and 0.02-500 μM with detection limits of 0.02, 0.002, and 0.005 μM (S/N = 3), respectively. For simultaneous detection by synchronous change of the concentrations of AA, DA, and UA, the linear response ranges were 1-800, 0.1-100, and 0.1-350 μM with detection limits of 0.28, 0.024, and 0.02 μM (S/N = 3), respectively. The fabricated sensors were further applied to the detection of AA, DA, and UA in urine samples. The Au@Pd-RGO nanocomposites have promising applications in highly sensitive and selective electrochemical sensing.Sensitive electrochemical sensors were fabricated with reduced graphene oxide-supported Au@Pd (Au@Pd-RGO) nanocomposites by one-step synthesis for individual and simultaneous determination of ascorbic acid (AA), dopamine (DA), and uric acid (UA) with low detection limits and wide concentration ranges. From the Au@Pd-RGO-modified electrodes, well-separated oxidation peaks and enhanced peak currents of AA, DA, and UA were observed owing to the superior conductivity of RGO and the excellent catalytic activity of Au@Pd nanoparticles. For individual detection, the linear responses of AA, DA, and UA were in the concentration ranges of 0.1-1000, 0.01-100, and 0.02-500 μM with detection limits of 0.02, 0.002, and 0.005 μM (S/N = 3), respectively. For simultaneous detection by synchronous change of the concentrations of AA, DA, and UA, the linear response ranges were 1-800, 0.1-100, and 0.1-350 μM with detection limits of 0.28, 0.024, and 0.02 μM (S/N = 3), respectively. The fabricated sensors were further applied to the detection of AA, DA, and UA in urine samples. The Au@Pd-RGO nanocomposites have promising applications in highly sensitive and selective electrochemical sensing. Electronic supplementary information (ESI) available: pH optimization, comparison of sensor performances, interference experiments, and detection in urine samples. See DOI: 10.1039/c4nr01774a

QWIPs at IRnova, a status update

NASA Astrophysics Data System (ADS)

Martijn, Henk; Gamfeldt, Anders; Asplund, Carl; Smuk, Sergiy; Kataria, Himanshu; Costard, Eric

2016-05-01

IRnova has a long history of producing QWIPs for the LWIR band. In this paper we give an overview of the current products (FPAs with 640x480 and 384x288 pixels respectively, and 25 μm pitch) and their performance. Their superior stability and uniformity inherent to detectors based on III/V material system will be demonstrated. Furthermore, an IDCA specifically designed for hand-held systems used for the detection of SF6 gas using a 0.5 W cooler will be presented. The detector format is 320x256 pixels with 30 μm pitch using the ISC9705 read out circuit. The peak wavelength is at 10.55 μm and the NETD is 22 mK.

Broadband spectroscopic sensor for real-time monitoring of industrial SO(2) emissions.

PubMed

Xu, Feng; Zhang, Yungang; Somesfalean, Gabriel; Wang, Huashan; Wu, Shaohua; Zhang, Zhiguo

2007-05-01

A spectroscopic system for continuous real-time monitoring of SO(2) concentrations in industrial emissions was developed. The sensor is well suited for field applications due to simple and compact instrumental design, and robust data evaluation based on ultraviolet broadband absorption without the use of any calibration cell. The sensor has a detection limit of 1 ppm, and was employed both for gas-flow simulations with and without suspended particles, and for in situ measurement of SO(2) concentrations in the flue gas emitted from an industrial coal-fired boiler. The price/performance ratio of the instrument is expected to be superior to other comparable real-time monitoring systems.

Chromosomal Microarray Testing in 42 Korean Patients with Unexplained Developmental Delay, Intellectual Disability, Autism Spectrum Disorders, and Multiple Congenital Anomalies.

PubMed

Lee, Sun Ho; Song, Wung Joo

2017-09-01

Chromosomal microarray (CMA) is a high-resolution, high-throughput method of identifying submicroscopic genomic copy number variations (CNVs). CMA has been established as the first-line diagnostic test for individuals with developmental delay (DD), intellectual disability (ID), autism spectrum disorders (ASDs), and multiple congenital anomalies (MCAs). CMA analysis was performed in 42 Korean patients who had been diagnosed with unexplained DD, ID, ASDs, and MCAs. Clinically relevant CNVs were discovered in 28 patients. Variants of unknown significance were detected in 13 patients. The diagnostic yield was high (66.7%). CMA is a superior diagnostic tool compared with conventional karyotyping and fluorescent in situ hybridization.

Severe Obstructive Calcification of the Descending Aorta: A Case Report of “Coral Reef Aorta”

PubMed Central

Ishigaki, Takahiro; Matsuda, Hitoshi; Henmi, Soichiro; Yoshida, Masato; Mukohara, Nobuhiko

2017-01-01

An 82-year-old man suffering from lower back pain and dyspnea presented to our institute in a state of shock. Computed tomography showed subtotal occlusion of the descending aorta with massive atherosclerotic calcification. As the proximal portion of the superior mesenteric artery was obstructed, emergency bypass from the right axillary artery to the bilateral external iliac arteries was performed, but the patient died 2 days later. Autopsy revealed that reddish-brown and verrucous masses obstructed the descending aorta, and high-grade thickening of the intima and extensive deposits of calcium in the lumina and medial layer were detected in the descending aorta histologically. PMID:29034045

Soft-information flipping approach in multi-head multi-track BPMR systems

NASA Astrophysics Data System (ADS)

Warisarn, C.; Busyatras, W.; Myint, L. M. M.

2018-05-01

Inter-track interference is one of the most severe impairments in bit-patterned media recording system. This impairment can be effectively handled by a modulation code and a multi-head array jointly processing multiple tracks; however, such a modulation constraint has never been utilized to improve the soft-information. Therefore, this paper proposes the utilization of modulation codes with an encoded constraint defined by the criteria for soft-information flipping during a three-track data detection process. Moreover, we also investigate the optimal offset position of readheads to provide the most improvement in system performance. The simulation results indicate that the proposed systems with and without position jitter are significantly superior to uncoded systems.

Minimal hardware Bluetooth tracking for long-term at-home elder supervision.

PubMed

Kelly, Damian; McLoone, Sean; Farrell, Ronan

2010-01-01

The ability to automatically detect the location of an elder within their own home is a significant enabler of remote elder supervision and interaction applications. This location information is typically generated via a myriad of sensors throughout the home environment. Even with high sensor redundancy, there are still situations where traditional elder monitoring systems are unable to resolve the location of the elder. This work develops a minimal infrastructure radio-frequency localisation system for long-term elder location tracking. An RFID room-labelling technique is employed and with it, the localisation system developed in this work is shown to exhibit superior performance to more traditional localisation systems in realistic long-term deployments.

Advances in Multi-Pixel Photon Counter technology: First characterization results

NASA Astrophysics Data System (ADS)

Bonanno, G.; Marano, D.; Romeo, G.; Garozzo, S.; Grillo, A.; Timpanaro, M. C.; Catalano, O.; Giarrusso, S.; Impiombato, D.; La Rosa, G.; Sottile, G.

2016-01-01

Due to the recent advances in silicon photomultiplier technology, new types of Silicon Photomultiplier (SiPM), also named Multi-Pixel Photon Counter (MPPC) detectors have become recently available, demonstrating superior performance in terms of their most important electrical and optical parameters. This paper presents the latest characterization results of the novel Low Cross-Talk (LCT) MPPC families from Hamamatsu, where a noticeable fill-factor enhancement and cross-talk reduction is achieved. In addition, the newly adopted resin coating has been proven to yield improved photon detection capabilities in the 280-320 nm spectral range, making the new LCT MPPCs particularly suitable for emerging applications like Cherenkov Telescope Array, and Astroparticle Physics.

The Applications of Gold Nanoparticle-Initialed Chemiluminescence in Biomedical Detection

NASA Astrophysics Data System (ADS)

Liu, Zezhong; Zhao, Furong; Gao, Shandian; Shao, Junjun; Chang, Huiyun

2016-10-01

Chemiluminescence technique as a novel detection method has gained much attention in recent years owning to the merits of high sensitivity, wider linear ranges, and low background signal. Similarly, nanotechnology especially for gold nanoparticles has emerged as detection tools due to their unique physical and chemical properties. Recently, it has become increasingly popular to couple gold nanoparticles with chemiluminescence technique in biological agents' detection. In this review, we describe the superiority of both chemiluminescence and gold nanoparticles and conclude the different applications of gold nanoparticle-initialed chemiluminescence in biomedical detection.

Residual symptoms after surgery for unilateral congenital superior oblique palsy.

PubMed

Caca, Ihsan; Sahin, Alparslan; Cingu, Abdullah; Ari, Seyhmus; Akbas, Umut

2012-01-01

To establish the surgical results and residual symptoms in 48 cases with unilateral congenital superior oblique muscle palsy that had surgical intervention to the vertical muscles alone. Myectomy and concomitant disinsertion of the inferior oblique (IO) muscle was performed in 38 cases and myectomy and concomitant IO disinsertion and recession of the superior rectus muscle in the ipsilateral eye was performed in 10 cases. The preoperative and postoperative vertical deviation values and surgical results were compared. Of the patients who had myectomy and concomitant IO disinsertion, 74% achieved an "excellent" result, 21% a "good" result, and 5% a "poor" result postoperatively. The difference in deviation between preoperative and postoperative values was statistically significant (P < .001). Of the patients who had myectomy and concomitant inferior oblique disinsertion and ipsilateral superior rectus recession, 50% achieved an "excellent" result, 20% a "good" result, and 30% a "poor" result postoperatively. The difference in deviation between preoperative and postoperative values was statistically significant (P < .001). Both procedures are effective and successful in patients with superior oblique muscle palsy, but a secondary surgery may be required. Copyright 2012, SLACK Incorporated.

Morphological relationship between the superior cervical ganglion and cervical nerves in Japanese cadaver donors.

PubMed

Mitsuoka, Kazuyuki; Kikutani, Takeshi; Sato, Iwao

2017-02-01

There are various communications between the superior cervical ganglion (SCG) and the vagus and glossopharyngeal nerves. However, little information exists concerning the origin of these sympathetic ganglion branches at the superior, middle, and inferior regions of the human SCG. The aim of this study was to describe the human SCG in a morphometric manner with the communication with cranial and cervical nerves and supply. This study characterized 72 SCG samples from 54 elderly Japanese human cadavers (30 males, 24 females; 65-100 years old). The SCG size (length, width, and thickness) and location were measured from the jugular foramen. We also defined the communication branches of the SCG to the vagus, glossopharyngeal, cervical, and accessory nerves at three regions (superior, middle, and inferior regions) of the SCG. Finally, we examined the arrangement and origin of the branch communications in detail and confirmed our observations, using histological sections of the SCG. The SCG in all cadaver donors was detected at the C2 and C3 vertebra levels. The number of SCG branches supplied the communicating branches, such as the carotid branch, communicating branch of the vagus nerve, and glossopharyngeal nerve, were frequently detected in the superior region of the SCG (χ 2  = 587.72, df = 26, p  <   .001). The number of ganglion cells with a large number of neurons per unit area (1 mm 2 ) was most often found in the middle region with shrunken neurons of the SCG compared with other regions. The communication branches of the SCG are mainly connected to the vagus and glossopharyngeal nerves. Characterizing these branches can provide useful data for head and neck ganglion block and surgical treatments.

Bearing performance degradation assessment based on time-frequency code features and SOM network

NASA Astrophysics Data System (ADS)

Zhang, Yan; Tang, Baoping; Han, Yan; Deng, Lei

2017-04-01

Bearing performance degradation assessment and prognostics are extremely important in supporting maintenance decision and guaranteeing the system’s reliability. To achieve this goal, this paper proposes a novel feature extraction method for the degradation assessment and prognostics of bearings. Features of time-frequency codes (TFCs) are extracted from the time-frequency distribution using a hybrid procedure based on short-time Fourier transform (STFT) and non-negative matrix factorization (NMF) theory. An alternative way to design the health indicator is investigated by quantifying the similarity between feature vectors using a self-organizing map (SOM) network. On the basis of this idea, a new health indicator called time-frequency code quantification error (TFCQE) is proposed to assess the performance degradation of the bearing. This indicator is constructed based on the bearing real-time behavior and the SOM model that is previously trained with only the TFC vectors under the normal condition. Vibration signals collected from the bearing run-to-failure tests are used to validate the developed method. The comparison results demonstrate the superiority of the proposed TFCQE indicator over many other traditional features in terms of feature quality metrics, incipient degradation identification and achieving accurate prediction. Highlights • Time-frequency codes are extracted to reflect the signals’ characteristics. • SOM network served as a tool to quantify the similarity between feature vectors. • A new health indicator is proposed to demonstrate the whole stage of degradation development. • The method is useful for extracting the degradation features and detecting the incipient degradation. • The superiority of the proposed method is verified using experimental data.

Selecting global climate models for regional climate change studies

PubMed Central

Pierce, David W.; Barnett, Tim P.; Santer, Benjamin D.; Gleckler, Peter J.

2009-01-01

Regional or local climate change modeling studies currently require starting with a global climate model, then downscaling to the region of interest. How should global models be chosen for such studies, and what effect do such choices have? This question is addressed in the context of a regional climate detection and attribution (D&A) study of January-February-March (JFM) temperature over the western U.S. Models are often selected for a regional D&A analysis based on the quality of the simulated regional climate. Accordingly, 42 performance metrics based on seasonal temperature and precipitation, the El Nino/Southern Oscillation (ENSO), and the Pacific Decadal Oscillation are constructed and applied to 21 global models. However, no strong relationship is found between the score of the models on the metrics and results of the D&A analysis. Instead, the importance of having ensembles of runs with enough realizations to reduce the effects of natural internal climate variability is emphasized. Also, the superiority of the multimodel ensemble average (MM) to any 1 individual model, already found in global studies examining the mean climate, is true in this regional study that includes measures of variability as well. Evidence is shown that this superiority is largely caused by the cancellation of offsetting errors in the individual global models. Results with both the MM and models picked randomly confirm the original D&A results of anthropogenically forced JFM temperature changes in the western U.S. Future projections of temperature do not depend on model performance until the 2080s, after which the better performing models show warmer temperatures. PMID:19439652

Evaluation of a newly designed sandwich enzyme linked immunosorbent assay for the detection of hydatid antigen in serum, urine and cyst fluid for diagnosis of cystic echinococcosis.

PubMed

Chaya, Dr; Parija, Subhash Chandra

2013-07-01

Cystic echinococcosis (CE) is a zoonotic disease of humans with variable clinical manifestations. Imaging and immunological methods are currently the mainstay of diagnosis of this disease. Although the immunological tests for detection of anti-echinococcal antibodies have several disadvantages, they are widely being used. Antigen is far more superior than antibody detection test as they can provide a specific parasitic diagnosis. A sandwich enzyme linked immunosorbent assay (ELISA) was designed using antibodies to 24 kDa urinary hydatid antigen for the detection of hydatid antigens in urine, serum and cyst fluid specimens. The performance of this novel test was compared with that of other hydatid antibody detection ELISA and enzyme immune transfer blot (EITB) using radiological and surgical confirmation as the gold standard. The antigen detection ELISA showed 100% sensitivity and specificity when tested with cyst fluid. On testing urine and serum, the antigen detection ELISA was found to be more specific than antibody detection ELISA. EITB was found to be the most sensitive and specific test. ELISA using polyclonal antibodies against 24 kDa urinary hydatid protein was moderately sensitive to detect hydatid antigen in serum and urine. Hence polyclonal antibodies to 24 kDa urinary hydatid antigen can be used as an alternative source of antibody to detect hydatid antigen in serum, urine and cyst fluid. In the present study, EITB was found to be highly specific test for detection of hydatid antibodiesin serum. 24 kDa protein was found to be specific and of diagnostic value in CE.

Fast Track ultrasound protocol to detect acute complications after totally implantable venous access device placement.

PubMed

Wu, Chun-Yu; Lin, Feng-Sheng; Wang, Yi-Chia; Chou, Wei-Han; Lin, Wen-Ying; Sun, Wei-Zen; Lin, Chih-Peng

2015-01-01

The role of ultrasound examination in detection of postprocedure complications from totally implantable venous access devices (TIVAD) placement is still uncertain. In a cohort of 665 cancer outpatients, we assessed a quick ultrasound examination protocol in early detection of mechanical complications of catheterization. Immediately after TIVAD placement, an ultrasound examination and chest radiography were performed to detect hemothorax, pneumothorax, and catheter malposition. The two methods were compared. Of the 668 catheters inserted, 628 were placed into axillary veins and 40 into internal jugular veins. The ultrasound examination took 2.5 ± 1.1 min. No hemothorax was detected, and neither pneumothorax nor catheter malposition was evident among the 40 internal jugular vein cannulations. Ultrasound and chest radiography examinations of the 628 axillary vein cannulations detected five and four instances of pneumothorax, respectively. Ultrasound detected all six catheter malpositions into the internal jugular vein. However, ultrasound failed to detect two out of three malpositions in the contralateral brachiocephalic vein and one kinking inside the superior vena cava. Without revision surgery, the operating time was 34.1 ± 15.6 min. With revision surgery, the operating time was shorter when ultrasound detected catheter malposition than when chest radiography was used (96.8 ± 12.9 vs. 188.8 ± 10.3 min, p < 0.001). Postprocedure ultrasound examination is a quick and sensitive method to detect TIVAD-related pneumothorax. It also precisely detects catheter malposition to internal jugular vein thus reduces time needed for revision surgery while chest radiography remains necessary to confirm catheter final position.

Staging of neuroendocrine tumours: comparison of [68Ga]DOTATOC multiphase PET/CT and whole-body MRI

PubMed Central

Schwenzer, N. F.; Sperling, O.; Aschoff, P.; Lichy, M. P.; Müller, M.; Brendle, C.; Werner, M. K.; Claussen, C. D.; Pfannenberg, C.

2013-01-01

Abstract Purpose: In patients with a neuroendocrine tumour (NET), the extent of disease strongly influences the outcome and multidisciplinary therapeutic management. Thus, systematic analysis of the diagnostic performance of the existing staging modalities is necessary. The aim of this study was to compare the diagnostic performance of 2 whole-body imaging modalities, [68Ga]DOTATOC positron emission tomography (PET)/computed tomography (CT) and magnetic resonance imaging (MRI) in patients with NET with regard to possible impact on treatment decisions. Materials and methods: [68Ga]DOTATOC-PET/CT and whole-body magnetic resonance imaging (wbMRI) were performed on 51 patients (25 females, 26 males, mean age 57 years) with histologically proven NET and suspicion of metastatic spread within a mean interval of 2.4 days (range 0–28 days). PET/CT was performed after intravenous administration of 150 MBq [68Ga]DOTATOC. The CT protocol comprised multiphase contrast-enhanced imaging. The MRI protocol consisted of standard sequences before and after intravenous contrast administration at 1.5 T. Each modality (PET, CT, PET/CT, wbMRI) was evaluated independently by 2 experienced readers. Consensus decision based on correlation of all imaging data, histologic and surgical findings and clinical follow-up was established as the standard of reference. Lesion-based and patient-based analysis was performed. Detection rates and accuracy were compared using the McNemar test. P values <0.05 were considered significant. The impact of whole-body imaging on the treatment decision was evaluated by the interdisciplinary tumour board of our institution. Results: 593 metastatic lesions were detected in 41 of 51 (80%) patients with NET (lung 54, liver 266, bone 131, lymph node 99, other 43). One hundred and twenty PET-negative lesions were detected by CT or MRI. Of all 593 lesions detected, PET identified 381 (64%) true-positive lesions, CT 482 (81%), PET/CT 545 (92%) and wbMRI 540 (91%). Comparison of lesion-based detection rates between PET/CT and wbMRI revealed significantly higher sensitivity of PET/CT for metastatic lymph nodes (100% vs 73%; P < 0.0001) and pulmonary lesions (100% vs 87%; P = 0.0233), whereas wbMRI had significantly higher detection rates for liver (99% vs 92%; P < 0.0001) and bone lesions (96% vs 82%; P < 0.0001). Of all 593 lesions, 22 were found only in PET, 11 only in CT and 47 only in wbMRI. The patient-based overall assessment of the metastatic status of the patient showed comparable sensitivity of PET/CT and MRI with slightly higher accuracy of PET/CT. Patient-based analysis of metastatic organ involvement revealed significantly higher accuracy of PET/CT for bone and lymph node metastases (100% vs 88%; P = 0.0412 and 98% vs 78%; P = 0.0044) and for the overall comparison (99% vs 89%; P < 0.0001). The imaging results influenced the treatment decision in 30 patients (59%) with comparable information from PET/CT and wbMRI in 30 patients, additional relevant information from PET/CT in 16 patients and from wbMRI in 7 patients. Conclusion: PET/CT and wbMRI showed comparable overall lesion-based detection rates for metastatic involvement in NET but significantly differed in organ-based detection rates with superiority of PET/CT for lymph node and pulmonary lesions and of wbMRI for liver and bone metastases. Patient-based analysis revealed superiority of PET/CT for NET staging. Individual treatment strategies benefit from complementary information from PET/CT and MRI. PMID:23466785

Hybrid SnO2/TiO2 Nanocomposites for Selective Detection of Ultra-Low Hydrogen Sulfide Concentrations in Complex Backgrounds

PubMed Central

Larin, Alexander; Womble, Phillip C.; Dobrokhotov, Vladimir

2016-01-01

In this paper, we present a chemiresistive metal oxide (MOX) sensor for detection of hydrogen sulfide. Compared to the previous reports, the overall sensor performance was improved in multiple characteristics, including: sensitivity, selectivity, stability, activation time, response time, recovery time, and activation temperature. The superior sensor performance was attributed to the utilization of hybrid SnO2/TiO2 oxides as interactive catalytic layers deposited using a magnetron radio frequency (RF) sputtering technique. The unique advantage of the RF sputtering for sensor fabrication is the ability to create ultra-thin films with precise control of geometry, morphology and chemical composition of the product of synthesis. Chemiresistive films down to several nanometers can be fabricated as sensing elements. The RF sputtering technique was found to be very robust for bilayer and multilayer oxide structure fabrication. The geometry, morphology, chemical composition and electronic structure of interactive layers were evaluated in relation to their gas sensing performance, using scanning electron microscopy (SEM), X-ray diffraction technique (XRD), atomic force microscopy (AFM), Energy Dispersive X-ray Spectroscopy (EDAX), UV visible spectroscopy, and Kelvin probe measurements. A sensor based on multilayer SnO2/TiO2 catalytic layer with 10% vol. content of TiO2 demonstrated the best gas sensing performance in all characteristics. Based on the pattern relating material’s characteristics to gas sensing performance, the optimization strategy for hydrogen sulfide sensor fabrication was suggested. PMID:27618900

The influence of schizotypal traits on attention under high perceptual load.

PubMed

Stotesbury, Hanne; Gaigg, Sebastian B; Kirhan, Saim; Haenschel, Corinna

2018-03-01

Schizophrenia Spectrum Disorders (SSD) are known to be characterised by abnormalities in attentional processes, but there are inconsistencies in the literature that remain unresolved. This article considers whether perceptual resource limitations play a role in moderating attentional abnormalities in SSD. According to perceptual load theory, perceptual resource limitations can lead to attenuated or superior performance on dual-task paradigms depending on whether participants are required to process, or attempt to ignore, secondary stimuli. If SSD is associated with perceptual resource limitations, and if it represents the extreme end of an otherwise normally distributed neuropsychological phenotype, schizotypal traits in the general population should lead to disproportionate performance costs on dual-task paradigms as a function of the perceptual task demands. To test this prediction, schizotypal traits were quantified via the Schizotypal Personality Questionnaire (SPQ) in 74 healthy volunteers, who also completed a dual-task signal detection paradigm that required participants to detect central and peripheral stimuli across conditions that varied in the overall number of stimuli presented. The results confirmed decreasing performance as the perceptual load of the task increased. More importantly, significant correlations between SPQ scores and task performance confirmed that increased schizotypal traits, particularly in the cognitive-perceptual domain, are associated with greater performance decrements under increasing perceptual load. These results confirm that attentional difficulties associated with SSD extend sub-clinically into the general population and suggest that cognitive-perceptual schizotypal traits may represent a risk factor for difficulties in the regulation of attention under increasing perceptual load.

Indocyanine green videoangiography "in negative": definition and usefulness in spinal dural arteriovenous fistulae.

PubMed

Simal Julián, Juan Antonio; Miranda Lloret, Pablo; López González, Antonio; Evangelista Zamora, Rocío; Botella Asunción, Carlos

2013-05-01

Indocyanine green videoangiography (IGV) has proven its effectiveness in the field of exovascular neurosurgery, both in the intracranial and spinal compartment, but is necessary to define a systematic process for the performance of the IGV to facilitate its interpretation during the procedure. We have defined and applied the concept of videoangiography "in negative" (INIGV) to spinal dural arteriovenous fistulae (dAVF) for the detection and treatment of arteriovenous shunts, so called because the first phase is performed with the vessel suggestive of being pathological occluded. A Pentero-operating microscope with near-infrared IGV-integrated system (Carl Zeiss Co., Germany) was used. At our institution, 24 patients were treated for a spinal dAVF between 1995 and 2011, only in the last 4 cases, INIGV was performed. We describe the IGV in negative procedure and show the most illustrative cases. In all cases, the fistula occlusion was confirmed by postoperative selective digital subtraction angiography (DSA). INIGV demonstrate its capacity in detecting vessels not actually arterialized that should be respected and avoid some of the main limitations of the conventional IGV. This is a technical description about an Indocyanine green (ICG) videoangiographic procedure modification that is superior to merely performing ICG before and after clipping of a dAVF. The INIGV results are rapid and easy to interpret procedure and provide great advantages to the dAVF treatment. Nevertheless, further studies are needed with a larger sample size to determine if INIGV may reduce the need to perform immediate postoperative DSA.

The Right Hemisphere Advantage in Visual Change Detection Depends on Temporal Factors

ERIC Educational Resources Information Center

Spotorno, Sara; Faure, Sylvane

2011-01-01

What accounts for the Right Hemisphere (RH) functional superiority in visual change detection? An original task which combines one-shot and divided visual field paradigms allowed us to direct change information initially to the RH or the Left Hemisphere (LH) by deleting, respectively, an object included in the left or right half of a scene…

Fluorescence in situ hybridization is superior for monitoring Epstein Barr viral load in infectious mononucleosis patients.

PubMed

Cao, Pengfei; Zhang, Meili; Wang, Wei; Dai, Yafei; Sai, Buqing; Sun, Jun; Wang, Lujuan; Wang, Fan; Li, Guiyuan; Xiang, Juanjuan

2017-05-03

Epstein Barr virus (EBV) plays a causal role in some diseases, including infectious mononucleosis, lymphoproliferative diseases and nasopharyngeal carcinoma. Detection of EBV infection has been shown to be a useful tool for diagnosing EBV-related diseases. In the present study, we compared the performance of molecular tests, including fluorescence in situ hybridization (FISH) and EBV real-time PCR, to those of serological assays for the detection of EBV infection. Thirty-eight patients with infectious mononucleosis (IM) were enrolled, of whom 31 were diagnosed with a mild type, and seven were diagnosed with IM with haemophagocytic lymphohistiocytosis and chronic active EBV infection. Twenty healthy controls were involved in the study. The atypical lymphocytes in peripheral blood were detected under a microscope and the percentage of positive cells was calculated. EBV DNA load in peripheral blood was detected using real-time PCR. The FISH assay was developed to detect the EBV genome from peripheral blood mononuclear cells (PBMC). Other diagnosis methods including the heterophil agglutination (HA) test and EBV-VCA-IgM test, to detect EBV were also compared. SPSS17.0 was used for statistical analysis. In all, 5-41% atypical lymphocytes were found among the PBMC in mild IM patients, whereas 8-51% atypical lymphocytes were found in IM patients with haemophagocytic lymphohistiocytosis and chronic active EBV infection patients. There was no significant difference in the ratios of atypical lymphoma between patients of the different types. We observed that 71.2% of mild IM patients and 85.7% of IM patients with haemophagocytic lymphohistiocytosis and chronic active EBV infection patients were positive for EBV-VCA-IgM. EBV-VCA-IgM was negative in all healthy control subjects. In addition, 67.1% of mild IM patients tested heterophile antibody positive, whereas 71.4% of IM patients with haemophagocytic lymphohistiocytosis and chronic active EBV infection tested positive. EBV DNA detected using real-time PCR was observed in 89.5% of these IM patients. The EBV genome was detected by the FISH assay in 97.4% of the IM patients. The EB viral loads detected by FISH and real-time PCR increased with the severity of IM. The EBV genome was detected in almost all the PBMC of IM with haemophagocytic lymphohistiocytosis and chronic active EBV infection patients. Molecular tests, including FISH and EBV real-time PCR, are more sensitive than serological assays for the detection of EBV infection. The FISH assay detecting EBV copies in unfractionated whole blood is preferable and superior to plasma real-time PCR in its reflection of the absolute viral burden circulating in the patients.

Combined operative technique with anterior surgical approach and video-assisted thoracoscopic surgical lobectomy for anterior superior sulcus tumours.

PubMed

Yokoyama, Yuhei; Chen, Fengshi; Aoyama, Akihiro; Sato, Toshihiko; Date, Hiroshi

2014-11-01

Video-assisted thoracoscopic surgery (VATS) has been widely used, but surgical resections of superior sulcus tumours remain challenging because of their anatomical location. For such cases, less-invasive procedures, such as the anterior transcervical-thoracic and transmanubrial approaches, have been widely performed because of their excellent visualization of the subclavian vessels. Recently, a combined operative technique with an anterior surgical approach and VATS for anterior superior sulcus tumours has been introduced. Herein, we report three cases of anterior superior sulcus tumours successfully resected by surgical approaches combined with a VATS-based lobectomy. In all cases, operability was confirmed by VATS, and upper lobectomies with hilar and mediastinal lymph node dissections were performed. Subsequently, dissections of the anterior inlet of the tumours were performed using the transmanubrial approach in two patients and the anterior trans-cervical-thoracic approach in one patient. Both approaches provided excellent access to the anterior inlet of the tumour and exposure of the subclavian vessels, resulting in radical resection of the tumour with concomitant resection of the surrounding anatomical structures, including the chest wall and vessels. In conclusion, VATS lobectomy combined with the anterior surgical approach might be an excellent procedure for the resection of anterior superior sulcus tumours. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Secondary visual workload capability with primary visual and kinesthetic-tactual displays

NASA Technical Reports Server (NTRS)

Gilson, R. D.; Burke, M. W.; Jagacinski, R. J.

1978-01-01

Subjects performed a cross-adaptive tracking task with a visual secondary display and either a visual or a quickened kinesthetic-tactual (K-T) primary display. The quickened K-T display resulted in superior secondary task performance. Comparisons of secondary workload capability with integrated and separated visual displays indicated that the superiority of the quickened K-T display was not simply due to the elimination of visual scanning. When subjects did not have to perform a secondary task, there was no significant difference between visual and quickened K-T displays in performing a critical tracking task.

Breast cancer detection using time reversal

NASA Astrophysics Data System (ADS)

Sheikh Sajjadieh, Mohammad Hossein

Breast cancer is the second leading cause of cancer death after lung cancer among women. Mammography and magnetic resonance imaging (MRI) have certain limitations in detecting breast cancer, especially during its early stage of development. A number of studies have shown that microwave breast cancer detection has potential to become a successful clinical complement to the conventional X-ray mammography. Microwave breast imaging is performed by illuminating the breast tissues with an electromagnetic waveform and recording its reflections (backscatters) emanating from variations in the normal breast tissues and tumour cells, if present, using an antenna array. These backscatters, referred to as the overall (tumour and clutter) response, are processed to estimate the tumour response, which is applied as input to array imaging algorithms used to estimate the location of the tumour. Due to changes in the breast profile over time, the commonly utilized background subtraction procedures used to estimate the target (tumour) response in array processing are impractical for breast cancer detection. The thesis proposes a new tumour estimation algorithm based on a combination of the data adaptive filter with the envelope detection filter (DAF/EDF), which collectively do not require a training step. After establishing the superiority of the DAF/EDF based approach, the thesis shows that the time reversal (TR) array imaging algorithms outperform their conventional conterparts in detecting and localizing tumour cells in breast tissues at SNRs ranging from 15 to 30dB.

Superior limbic keratoconjunctivitis associated with cosmetic soft contact lens wear.

PubMed

Fuerst, D J; Sugar, J; Worobec, S

1983-08-01

Thirteen patients who wore soft contact lenses were seen with a syndrome consistent with superior limbic keratoconjunctivitis. An irregular epithelial surface, punctate staining with fluorescein, and subepithelial infiltrates were found on the superior aspect of the corneas in association with hyperemia of the superior bulbar conjunctivae. The keratoconjunctivitis persisted as long as 15 months after discontinuation of lens wear. Patch testing with ophthalmic vehicle preservatives, performed on seven patients, failed to show a consistent hypersensitivity to any of the tested compounds, and three patients had used only preservative-free saline for lens care. The etiology of this syndrome is unknown.

PScan 1.0: flexible software framework for polygon based multiphoton microscopy

NASA Astrophysics Data System (ADS)

Li, Yongxiao; Lee, Woei Ming

2016-12-01

Multiphoton laser scanning microscopes exhibit highly localized nonlinear optical excitation and are powerful instruments for in-vivo deep tissue imaging. Customized multiphoton microscopy has a significantly superior performance for in-vivo imaging because of precise control over the scanning and detection system. To date, there have been several flexible software platforms catered to custom built microscopy systems i.e. ScanImage, HelioScan, MicroManager, that perform at imaging speeds of 30-100fps. In this paper, we describe a flexible software framework for high speed imaging systems capable of operating from 5 fps to 1600 fps. The software is based on the MATLAB image processing toolbox. It has the capability to communicate directly with a high performing imaging card (Matrox Solios eA/XA), thus retaining high speed acquisition. The program is also designed to communicate with LabVIEW and Fiji for instrument control and image processing. Pscan 1.0 can handle high imaging rates and contains sufficient flexibility for users to adapt to their high speed imaging systems.

TiO2-Based Nanoheterostructures for Promoting Gas Sensitivity Performance: Designs, Developments, and Prospects

PubMed Central

Wang, Yuan; Wu, Tao; Zhou, Yun; Meng, Chuanmin; Zhu, Wenjun; Liu, Lixin

2017-01-01

Gas sensors based on titanium dioxide (TiO2) have attracted much public attention during the past decades due to their excellent potential for applications in environmental pollution remediation, transportation industries, personal safety, biology, and medicine. Numerous efforts have therefore been devoted to improving the sensing performance of TiO2. In those effects, the construct of nanoheterostructures is a promising tactic in gas sensing modification, which shows superior sensing performance to that of the single component-based sensors. In this review, we briefly summarize and highlight the development of TiO2-based heterostructure gas sensing materials with diverse models, including semiconductor/semiconductor nanoheterostructures, noble metal/semiconductor nanoheterostructures, carbon-group-materials/semiconductor nano- heterostructures, and organic/inorganic nanoheterostructures, which have been investigated for effective enhancement of gas sensing properties through the increase of sensitivity, selectivity, and stability, decrease of optimal work temperature and response/recovery time, and minimization of detectable levels. PMID:28846621