Kataoka, Yuko; Ikezono, Tetsuo; Fukushima, Kunihiro; Yuen, Koji; Maeda, Yukihide; Sugaya, Akiko; Nishizaki, Kazunori
2013-08-01
Perilymphatic fistula (PLF) is defined as an abnormal leakage between perilymph from the labyrinth to the middle ear. Symptoms include hearing loss, tinnitus, and vertigo. The standard mode of PLF detection is intraoperative visualization of perilymph leakage and fistula, which ostensibly confirms the existence of PLF. Other possible methods of diagnosis include confirmation of pneumolabyrinth via diagnostic imaging. Recently, a cochlin-tomoprotein (CTP) detection test has been developed that allows definitive diagnosis of PLF-related hearing loss. We report the case of a 45-year-old man who presented with right-sided tinnitus, hearing loss, and dizziness 30 years after stapes surgery. Middle ear lavage was performed after myringotomy. A preoperative diagnosis of PLF was reached using the CTP detection test. Intraoperative observations included a necrotic long process of the incus, displaced wire piston, and fibrous tissue in the oval window. Perilymph leakage was not evident. The oval window was closed with fascia, and vertigo disappeared within 2 weeks postoperatively. When PLF is suspected after stapes surgery, the CTP detection test can be a useful, highly sensitive, and less invasive method for preoperative diagnosis. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
CTP (Cochlin-tomoprotein) detection in the profuse fluid leakage (gusher) from cochleostomy.
Ikezono, Tetsuo; Sugizaki, Kazuki; Shindo, Susumu; Sekiguchi, Satomi; Pawankar, Ruby; Baba, Shunkichi; Yagi, Toshiaki
2010-08-01
By testing 125 samples, we confirmed that Cochlin-tomoprotein (CTP) is present in the perilymph, not in cerebrospinal fluid (CSF). Perilymph and CSF exist in two distinct compartments, even in the case of a malformed inner ear with a bony defect in the lamina cribrosa, as described here. Cochleostomy might have suddenly decreased the perilymph pressure, allowing the influx of CSF into the inner ear resulting in profuse fluid leakage, first perilymph then CSF. The first purpose of this study was to further confirm the specificity of the perilymph-specific protein CTP that we reported recently. Secondly, we assessed the nature of the fluid leakage from the cochleostomy using the CTP detection test. A standardized CTP detection test was performed on 65 perilymph and 60 CSF samples. Samples of profuse fluid leakage collected from cochleostomy during cochlear implantation surgery of one patient with branchio-oto-renal (BOR) syndrome were also tested by the CTP detection test. CTP was detected in 60 of 65 perilymph samples but not in any of the CSF samples. The leaked fluid was shown to contain CTP, i.e. perilymph, at the outset, and then the CTP detection signals gradually disappeared as time elapsed.
Directory of Open Access Journals (Sweden)
Qi Wang
Full Text Available By analyzing the different phenotypes of two Chinese DFNA9 families with the same mutation located in the intervening region between the LCCL and vWFA domains of cochlin and testing the functional changes in the mutant cochlin, we investigated the different pathogeneses for mutations in LCCL and vWFA domains.Targeted next-generation sequencing for deafness-related genes was used to identify the mutation in the proband in family #208. The probands of family #208 and family #32 with the same p.C162Y mutation were followed for more than 3 years to evaluate the progression of hearing loss and vestibular dysfunction using pure-tone audiometry, caloric testing, electrocochleogram, vestibular-evoked myogenic potential, and video head-impulse test. The disruption of normal cleavage to produce secreted LCCL domain fragments and the tendency to form aggregations of mutant cochlins were tested by in vitro cell experiments.The two families showed different clinical symptoms. Family #32 was identified as having early-onset, progressive sensorineural hearing loss, similar to the symptoms in DFNA9 patients with cochlin mutations in the vWFA domain. The proband of family #208 endured late-onset recurrent paroxysmal vertigo attacks and progressively deteriorating hearing, similar to symptoms in those with cochlin mutations in the LCCL domain. We therefore suggest that the disrupted cleavage of the LCCL domain fragment is likely to cause vestibular dysfunction, and aggregation of mutant cochlin caused by mutations in the vWFA domain is responsible for early-onset hearing loss. The p.C162Y mutation causes either disruption of LCCL domain fragment cleavage or aggregation of mutant cochlin, resulting in the different phenotypes in the two families.This study demonstrates that DFNA9 families with the same genotype may have significantly different phenotypes. The mutation site in cochlin is related to the pathological mechanism underlying the different phenotypes.
Selection of tests for outlier detection
Bossers, H.C.M.; Hurink, Johann L.; Smit, Gerardus Johannes Maria
Integrated circuits are tested thoroughly in order to meet the high demands on quality. As an additional step, outlier detection is used to detect potential unreliable chips such that quality can be improved further. However, it is often unclear to which tests outlier detection should be applied and
Multisignal detecting system of pile integrity testing
Liu, Zuting; Luo, Ying; Yu, Shihai
2002-05-01
The low strain reflection wave method plays a principal rule in the integrating detection of base piles. However, there are some deficiencies with this method. For example, there is a blind area of detection on top of the tested pile; it is difficult to recognize the defects at deep-seated parts of the pile; there is still the planar of 3D domino effect, etc. It is very difficult to solve these problems only with the single-transducer pile integrity testing system. A new multi-signal piles integrity testing system is proposed in this paper, which is able to impulse and collect signals on multiple points on top of the pile. By using the multiple superposition data processing method, the detecting system can effectively restrain the interference and elevate the precision and SNR of pile integrity testing. The system can also be applied to the evaluation of engineering structure health.
Statistics of software vulnerability detection in certification testing
Barabanov, A. V.; Markov, A. S.; Tsirlov, V. L.
2018-05-01
The paper discusses practical aspects of introduction of the methods to detect software vulnerability in the day-to-day activities of the accredited testing laboratory. It presents the approval results of the vulnerability detection methods as part of the study of the open source software and the software that is a test object of the certification tests under information security requirements, including software for communication networks. Results of the study showing the allocation of identified vulnerabilities by types of attacks, country of origin, programming languages used in the development, methods for detecting vulnerability, etc. are given. The experience of foreign information security certification systems related to the detection of certified software vulnerabilities is analyzed. The main conclusion based on the study is the need to implement practices for developing secure software in the development life cycle processes. The conclusions and recommendations for the testing laboratories on the implementation of the vulnerability analysis methods are laid down.
Co-Testing of Cervical Screening Tests in Detection of High Grade Cervical Intraepithelial Neoplasia
Directory of Open Access Journals (Sweden)
Smita Asthana
2017-10-01
Full Text Available Introduction: Co-testing performance for detection of high grade Cervical Intraepithelial Neoplasia (CIN has not been adequately addressed from Low Resource Countries (LRCs. Where isolated tests do not have adequate performance, further explorations are recommended. Aim: To evaluate the co-testing of conventional cervical screening tests such as Papanicolaou (Pap and Visual Inspection Cervix with Acetic Acid (VIA, with care HPV on Cervical Samples (CHPV or on Vaginal Samples (VHPV in the detection of high grade CIN. Materials and Methods: The cross-sectional study was conducted on ever married women of age 30 to 59 years in a rural community of Dadri. Women were screened by CHPV, VHPV, and Pap and VIA methods. Confirmation of screen positives was done by histology. Sensitivity, Specificity and likelihood ratios of different combinations of test determined to evaluate the performance. Results: Total eligible women, 66.2% (5032/7604 responded for screening. Analysis was performed on 4658, after excluding those who did not complete all screenings. Co-testing of CHPV (OR=246 or VHPV (OR=278 with Pap had highest association. Positive likelihood ratios of CHPV and VHPV with Pap in CIN II+ detection rates were 13.0 and 11.8 and in CIN III+ the detection rates were 18.0 and 16.0 respectively. Higher sensitivities and specificities were observed in co-testing for CIN III+ detection as against CIN II+ lesions. Conclusion: Choice of co-testing in a pair of tests for detection of high grade CIN is likely to depend on whether screening is targeted for developed or low resource country. VIA in isolation might not yield optimal results for LRCs.
HIV resistance testing and detected drug resistance in Europe
DEFF Research Database (Denmark)
Schultze, Anna; Phillips, Andrew N; Paredes, Roger
2015-01-01
to Southern Europe. CONCLUSIONS: Despite a concurrent decline in virological failure and testing, drug resistance was commonly detected. This suggests a selective approach to resistance testing. The regional differences identified indicate that policy aiming to minimize the emergence of resistance......OBJECTIVES: To describe regional differences and trends in resistance testing among individuals experiencing virological failure and the prevalence of detected resistance among those individuals who had a genotypic resistance test done following virological failure. DESIGN: Multinational cohort...... study. METHODS: Individuals in EuroSIDA with virological failure (>1 RNA measurement >500 on ART after >6 months on ART) after 1997 were included. Adjusted odds ratios (aORs) for resistance testing following virological failure and aORs for the detection of resistance among those who had a test were...
ANOLE Portable Radiation Detection System Field Test and Evaluation Campaign
International Nuclear Information System (INIS)
Hodge, Chris A.
2007-01-01
Handheld, backpack, and mobile sensors are elements of the Global Nuclear Detection System for the interdiction and control of illicit radiological and nuclear materials. They are used by the U.S. Department of Homeland Security (DHS) and other government agencies and organizations in various roles for border protection, law enforcement, and nonproliferation monitoring. In order to systematically document the operational performance of the common commercial off-the-shelf portable radiation detection systems, the DHS Domestic Nuclear Detection Office conducted a test and evaluation campaign conducted at the Nevada Test Site from January 18 to February 27, 2006. Named 'Anole', it was the first test of its kind in terms of technical design and test complexities. The Anole test results offer users information for selecting appropriate mission-specific portable radiation detection systems. The campaign also offered manufacturers the opportunity to submit their equipment for independent operationally relevant testing to subsequently improve their detector performance. This paper will present the design, execution, and methodologies of the DHS Anole portable radiation detection system test campaign
Detecting Test Tampering Using Item Response Theory
Wollack, James A.; Cohen, Allan S.; Eckerly, Carol A.
2015-01-01
Test tampering, especially on tests for educational accountability, is an unfortunate reality, necessitating that the state (or its testing vendor) perform data forensic analyses, such as erasure analyses, to look for signs of possible malfeasance. Few statistical approaches exist for detecting fraudulent erasures, and those that do largely do not…
Fault detection in multiply-redundant measurement systems via sequential testing
International Nuclear Information System (INIS)
Ray, A.
1988-01-01
The theory and application of a sequential test procedure for fault detection and isolation. The test procedure is suited for development of intelligent instrumentation in strategic processes like aircraft and nuclear plants where redundant measurements are usually available for individual critical variables. The test procedure consists of: (1) a generic redundancy management procedure which is essentially independent of the fault detection strategy and measurement noise statistics, and (2) a modified version of sequential probability ratio test algorithm for fault detection and isolation, which functions within the framework of this redundancy management procedure. The sequential test procedure is suitable for real-time applications using commercially available microcomputers and its efficacy has been verified by online fault detection in an operating nuclear reactor. 15 references
Statistical Requirements For Pass-Fail Testing Of Contraband Detection Systems
International Nuclear Information System (INIS)
Gilliam, David M.
2011-01-01
Contraband detection systems for homeland security applications are typically tested for probability of detection (PD) and probability of false alarm (PFA) using pass-fail testing protocols. Test protocols usually require specified values for PD and PFA to be demonstrated at a specified level of statistical confidence CL. Based on a recent more theoretical treatment of this subject [1], this summary reviews the definition of CL and provides formulas and spreadsheet functions for constructing tables of general test requirements and for determining the minimum number of tests required. The formulas and tables in this article may be generally applied to many other applications of pass-fail testing, in addition to testing of contraband detection systems.
Memory detection 2.0: the first web-based memory detection test.
Kleinberg, Bennett; Verschuere, Bruno
2015-01-01
There is accumulating evidence that reaction times (RTs) can be used to detect recognition of critical (e.g., crime) information. A limitation of this research base is its reliance upon small samples (average n = 24), and indications of publication bias. To advance RT-based memory detection, we report upon the development of the first web-based memory detection test. Participants in this research (Study1: n = 255; Study2: n = 262) tried to hide 2 high salient (birthday, country of origin) and 2 low salient (favourite colour, favourite animal) autobiographical details. RTs allowed to detect concealed autobiographical information, and this, as predicted, more successfully so than error rates, and for high salient than for low salient items. While much remains to be learned, memory detection 2.0 seems to offer an interesting new platform to efficiently and validly conduct RT-based memory detection research.
Memory detection 2.0: the first web-based memory detection test.
Directory of Open Access Journals (Sweden)
Bennett Kleinberg
Full Text Available There is accumulating evidence that reaction times (RTs can be used to detect recognition of critical (e.g., crime information. A limitation of this research base is its reliance upon small samples (average n = 24, and indications of publication bias. To advance RT-based memory detection, we report upon the development of the first web-based memory detection test. Participants in this research (Study1: n = 255; Study2: n = 262 tried to hide 2 high salient (birthday, country of origin and 2 low salient (favourite colour, favourite animal autobiographical details. RTs allowed to detect concealed autobiographical information, and this, as predicted, more successfully so than error rates, and for high salient than for low salient items. While much remains to be learned, memory detection 2.0 seems to offer an interesting new platform to efficiently and validly conduct RT-based memory detection research.
Directory of Open Access Journals (Sweden)
Williams Narelle
2011-06-01
Full Text Available Abstract Background Cancer is a major cause of mortality and morbidity in patients with chronic kidney disease (CKD. In patients without kidney disease, screening is a major strategy for reducing the risk of cancer and improving the health outcomes for those who developed cancers by detecting treatable cancers at an early stage. Among those with CKD, the effectiveness, the efficacy and patients' preferences for cancer screening are unknown. Methods/Design This work describes the protocol for the DETECT study examining the effectiveness, efficiency and patient's perspectives of colorectal cancer screening using immunochemical faecal occult blood testing (iFOBT for people with CKD. The aims of the DETECT study are 1 to determine the test performance characteristics of iFOBT screening in individuals with CKD, 2 to estimate the incremental costs and health benefits of iFOBT screening in CKD compared to no screening and 3 to elicit patients' perspective for colorectal cancer screening in the CKD population. Three different study designs will be used to explore the uncertainties surrounding colorectal cancer screening in CKD. A diagnostic test accuracy study of iFOBT screening will be conducted across all stages of CKD in patients ages 35-70. Using individually collected direct healthcare costs and outcomes from the diagnostic test accuracy study, cost-utility and cost-effective analyses will be performed to estimate the costs and health benefits of iFOBT screening in CKD. Qualitative in-depth interviews will be undertaken in a subset of participants from the diagnostic test accuracy study to investigate the perspectives, experiences, attitudes and beliefs about colorectal cancer screening among individuals with CKD. Discussion The DETECT study will target the three major unknowns about early cancer detection in CKD. Findings from our study will provide accurate and definitive estimates of screening efficacy and efficiency for colorectal cancer, and
MAFF sponsored research: detection tests for irradiated food
International Nuclear Information System (INIS)
Blackburn, C.M.; Holley, P.A.; Pryke, D.C.
1993-01-01
In their 1986 report on the safety and wholesomeness of irradiated food the UK Advisory Committee on Irradiated and Novel Foods (ACINF) recognised that a generally applicable test to determine if a food had been irradiated was not available. The committee considered that, although not a pre-requisite, the existence of a detection test would be a useful supplement to a control system and do much to reassure consumers; with this in mind ACINF recommended that detection methods should be kept under review. As a consequence, in 1987 the Ministry initiated a comprehensive R and D detection test programme. Over fifty papers have been published to date as a result of this programme. MAFF (Ministry Of Agriculture Fisheries and Food) has also been involved in other research associated with irradiation and food safety, some of which is described in this paper. This paper aims to give an overview of recent work funded under the food irradiation programme. Twelve projects have been supported over the last two years, ten of which involved the development of detection tests for irradiated food. A summary of these projects is presented: - Thermoluminescence; - Electron Spin Resonance; - 2-alkylcyclobutanones; -Determination Of Hydrogen; - Differential Scanning Calorimetry; - Limulus Amoebocyte Lysate; - DNA; - Pesticide Breakdown; - Neutron Irradiation; -Future Plans. (orig./vhe)
Laser Obstacle Detection System Flight Testing
National Research Council Canada - National Science Library
Davis, Timothy
2003-01-01
...). The Aviation Applied Technology Directorate (AATD) was contracted to mount the HELLAS sensor on the nose of a UH-60L Blackhawk helicopter and to conduct flight tests to evaluate the HELLAS obstacle detection sensor...
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.
Test of TEDA, Tsunami Early Detection Algorithm
Bressan, Lidia; Tinti, Stefano
2010-05-01
Tsunami detection in real-time, both offshore and at the coastline, plays a key role in Tsunami Warning Systems since it provides so far the only reliable and timely proof of tsunami generation, and is used to confirm or cancel tsunami warnings previously issued on the basis of seismic data alone. Moreover, in case of submarine or coastal landslide generated tsunamis, which are not announced by clear seismic signals and are typically local, real-time detection at the coastline might be the fastest way to release a warning, even if the useful time for emergency operations might be limited. TEDA is an algorithm for real-time detection of tsunami signal on sea-level records, developed by the Tsunami Research Team of the University of Bologna. The development and testing of the algorithm has been accomplished within the framework of the Italian national project DPC-INGV S3 and the European project TRANSFER. The algorithm is to be implemented at station level, and it is based therefore only on sea-level data of a single station, either a coastal tide-gauge or an offshore buoy. TEDA's principle is to discriminate the first tsunami wave from the previous background signal, which implies the assumption that the tsunami waves introduce a difference in the previous sea-level signal. Therefore, in TEDA the instantaneous (most recent) and the previous background sea-level elevation gradients are characterized and compared by proper functions (IS and BS) that are updated at every new data acquisition. Detection is triggered when the instantaneous signal function passes a set threshold and at the same time it is significantly bigger compared to the previous background signal. The functions IS and BS depend on temporal parameters that allow the algorithm to be adapted different situations: in general, coastal tide-gauges have a typical background spectrum depending on the location where the instrument is installed, due to local topography and bathymetry, while offshore buoys are
Sequential detection of influenza epidemics by the Kolmogorov-Smirnov test
Directory of Open Access Journals (Sweden)
Closas Pau
2012-10-01
Full Text Available Abstract Background Influenza is a well known and common human respiratory infection, causing significant morbidity and mortality every year. Despite Influenza variability, fast and reliable outbreak detection is required for health resource planning. Clinical health records, as published by the Diagnosticat database in Catalonia, host useful data for probabilistic detection of influenza outbreaks. Methods This paper proposes a statistical method to detect influenza epidemic activity. Non-epidemic incidence rates are modeled against the exponential distribution, and the maximum likelihood estimate for the decaying factor λ is calculated. The sequential detection algorithm updates the parameter as new data becomes available. Binary epidemic detection of weekly incidence rates is assessed by Kolmogorov-Smirnov test on the absolute difference between the empirical and the cumulative density function of the estimated exponential distribution with significance level 0 ≤ α ≤ 1. Results The main advantage with respect to other approaches is the adoption of a statistically meaningful test, which provides an indicator of epidemic activity with an associated probability. The detection algorithm was initiated with parameter λ0 = 3.8617 estimated from the training sequence (corresponding to non-epidemic incidence rates of the 2008-2009 influenza season and sequentially updated. Kolmogorov-Smirnov test detected the following weeks as epidemic for each influenza season: 50−10 (2008-2009 season, 38−50 (2009-2010 season, weeks 50−9 (2010-2011 season and weeks 3 to 12 for the current 2011-2012 season. Conclusions Real medical data was used to assess the validity of the approach, as well as to construct a realistic statistical model of weekly influenza incidence rates in non-epidemic periods. For the tested data, the results confirmed the ability of the algorithm to detect the start and the end of epidemic periods. In general, the proposed test could
Evaluation of the white test for the intraoperative detection of bile leakage.
Leelawat, Kawin; Chaiyabutr, Kittipong; Subwongcharoen, Somboon; Treepongkaruna, Sa-Ad
2012-01-01
We assess whether the White test is better than the conventional bile leakage test for the intraoperative detection of bile leakage in hepatectomized patients. This study included 30 patients who received elective liver resection. Both the conventional bile leakage test (injecting an isotonic sodium chloride solution through the cystic duct) and the White test (injecting a fat emulsion solution through the cystic duct) were carried out in the same patients. The detection of bile leakage was compared between the conventional method and the White test. A bile leak was demonstrated in 8 patients (26.7%) by the conventional method and in 19 patients (63.3%) by the White test. In addition, the White test detected a significantly higher number of bile leakage sites compared with the conventional method (Wilcoxon signed-rank test; P detection of bile leakage. Based on our study, we recommend that surgeons investigating bile leakage sites during liver resections should use the White test instead of the conventional bile leakage test.
Cascaded image analysis for dynamic crack detection in material testing
Hampel, U.; Maas, H.-G.
Concrete probes in civil engineering material testing often show fissures or hairline-cracks. These cracks develop dynamically. Starting at a width of a few microns, they usually cannot be detected visually or in an image of a camera imaging the whole probe. Conventional image analysis techniques will detect fissures only if they show a width in the order of one pixel. To be able to detect and measure fissures with a width of a fraction of a pixel at an early stage of their development, a cascaded image analysis approach has been developed, implemented and tested. The basic idea of the approach is to detect discontinuities in dense surface deformation vector fields. These deformation vector fields between consecutive stereo image pairs, which are generated by cross correlation or least squares matching, show a precision in the order of 1/50 pixel. Hairline-cracks can be detected and measured by applying edge detection techniques such as a Sobel operator to the results of the image matching process. Cracks will show up as linear discontinuities in the deformation vector field and can be vectorized by edge chaining. In practical tests of the method, cracks with a width of 1/20 pixel could be detected, and their width could be determined at a precision of 1/50 pixel.
DN detection during SLSF tests
International Nuclear Information System (INIS)
Braid, T.H.; Harper, H.A.; Wilson, R.E.; Baldwin, R.D.; Gilbert, D.M.; Baxter, D.E.; Gillins, R.L.; Jeffries, G.L.
1982-01-01
During two tests in the Sodium Loop Safety Facility (W2 and P4), two systems were operated to detect delayed neutrons from exposed fuel. One monitored directly the sodium in the in-pile loop with a transit delay from the flux region of approx.2 seconds; the other conducted a sample stream of sodium to external detectors with a transit delay which could be varied from approx.10 to approx. 40 seconds. Detectors of a wide range of sensitivity were operated in pulse and current mode; DN signals varying from 2 recoil to many grams of molten fuel could be recorded reliably without saturation. During the W2 and P4 tests a continuous DN record was made. Massive fuel failure signals were observed during reactor transients in both tests, including events interpreted as fuel melting and exposure of large areas. The steady signal from the blockage in P4 was studied as a function of reactor power and sodium temperature
Automated High-Speed Video Detection of Small-Scale Explosives Testing
Ford, Robert; Guymon, Clint
2013-06-01
Small-scale explosives sensitivity test data is used to evaluate hazards of processing, handling, transportation, and storage of energetic materials. Accurate test data is critical to implementation of engineering and administrative controls for personnel safety and asset protection. Operator mischaracterization of reactions during testing contributes to either excessive or inadequate safety protocols. Use of equipment and associated algorithms to aid the operator in reaction determination can significantly reduce operator error. Safety Management Services, Inc. has developed an algorithm to evaluate high-speed video images of sparks from an ESD (Electrostatic Discharge) machine to automatically determine whether or not a reaction has taken place. The algorithm with the high-speed camera is termed GoDetect (patent pending). An operator assisted version for friction and impact testing has also been developed where software is used to quickly process and store video of sensitivity testing. We have used this method for sensitivity testing with multiple pieces of equipment. We present the fundamentals of GoDetect and compare it to other methods used for reaction detection.
SCTI chemical leak detection test plan
International Nuclear Information System (INIS)
1981-01-01
Tests will be conducted on the CRBRP prototype steam generator at SCTI to determine the effects of steam generator geometry on the response of the CRBRP chemical leak detection system to small water-to-sodium leaks in various regions of the steam generator. Specifically, small injections of hydrogen gas (simulating water leaks) will be made near the two tubesheets, and the effective transport times to the main stream exit and vent line hydrogen meters will be measured. The magnitude and time characteristics of the meters' response will also be measured. This information will be used by the Small Leak Protection Base Program (SG027) for improved predictions of meter response times and leak detection sensitivity
A Space Object Detection Algorithm using Fourier Domain Likelihood Ratio Test
Becker, D.; Cain, S.
Space object detection is of great importance in the highly dependent yet competitive and congested space domain. Detection algorithms employed play a crucial role in fulfilling the detection component in the situational awareness mission to detect, track, characterize and catalog unknown space objects. Many current space detection algorithms use a matched filter or a spatial correlator to make a detection decision at a single pixel point of a spatial image based on the assumption that the data follows a Gaussian distribution. This paper explores the potential for detection performance advantages when operating in the Fourier domain of long exposure images of small and/or dim space objects from ground based telescopes. A binary hypothesis test is developed based on the joint probability distribution function of the image under the hypothesis that an object is present and under the hypothesis that the image only contains background noise. The detection algorithm tests each pixel point of the Fourier transformed images to make the determination if an object is present based on the criteria threshold found in the likelihood ratio test. Using simulated data, the performance of the Fourier domain detection algorithm is compared to the current algorithm used in space situational awareness applications to evaluate its value.
Hydrogen peroxide test for intraoperative bile leak detection.
Trehan, V; Rao, Pankaj P; Naidu, C S; Sharma, Anuj K; Singh, A K; Sharma, Sanjay; Gaur, Amit; Kulkarni, S V; Pathak, N
2017-07-01
Bile leakage (BL) is a common complication following liver surgery, ranging from 3 to 27% in different series. To reduce the incidence of post-operative BL various BL tests have been applied since ages, but no method is foolproof and every method has their own limitations. In this study we used a relatively simpler technique to detect the BL intra-operatively. Topical application of 1.5% diluted hydrogen peroxide (H 2 O 2 ) was used to detect the BL from cut surface of liver and we compared this with conventional saline method to know the efficacy. A total of 31 patients included all patients who underwent liver resection and donor hepatectomies as part of Living Donor Liver Transplantation. After complete liver resection, the conventional saline test followed by topical diluted 1.5% H 2 O 2 test was performed on all. A BL was demonstrated in 11 patients (35.48%) by the conventional saline method and in 19 patients (61.29%) by H 2 O 2 method. Statistically compared by Wilcoxon signed-rank test showed significant difference ( P = 0.014) for minor liver resections group and ( P = 0.002) for major liver resections group. The topical application of H 2 O 2 is a simple and effective method of detection of BL from cut surface of liver. It is an easy, non-invasive, cheap, less time consuming, reproducible, and sensitive technique with no obvious disadvantages.
Accuracy analysis of the CTBTO nuclear test detection scale and Improvement
Energy Technology Data Exchange (ETDEWEB)
Ryu, Young Kwang [Seoul National Univ., Seoul (Korea, Republic of)
2014-10-15
CTBTO (Comprehensive nuclear Test Ban Treaty Organization) is charge of nuclear test monitoring for nuclear non-proliferation. CTBTO has 170 seismic stations in operation in 76 countries in order to detect the artificial earthquake that was caused by an underground nuclear test. Korea use formula that is based on the equations that are used by the IMS (International Monitoring System) of CTBTO for analysis of explosive scale, and reflect the nature of the terrain, such as rock. But the expression for calculating the exact scale explosive is still un-established state. And generally CTBTO doesn't care about artificial explosive that is being received low-yield in accordance with the criteria of nuclear detection. But, at the time that North Korea conduct a nuclear test, it should not be overlooked that the scale of the earthquake detection criteria below. Because DPRK is trying to conceal their nuclear development capability, there are possibility of low-yield nuclear test or possibility of install a buffer to hide actual explosive scale. These radionuclide observations were consistent with a DPRK low-yield nuclear test on May 2010, even though no seismic signals from such a test have been detected. But there were a few times of low-yield (magnitude 1.39-1.93) occurred around DPRK nuclear test site at that time.
Comparative efficacy of antigen and antibody detection tests for human trichinellosis
International Nuclear Information System (INIS)
Ivanoska, D.; Cuperlovic, K.; Gamble, H.R.; Murrell, K.D.
1989-01-01
Sera collected from patients with suspected or confirmed exposure to Trichinella spiralis were tested for circulating parasite antigens and antiparasite antibodies. Using an immunoradiometric assay, excretory--secretory antigens from muscle-stage larvae of T. spiralis were detected in the sera of 47% of 62 patients with clinical trichinellosis and 13% of 39 patients without clinical signs but suspected of exposure to infected meat. In comparison, antibodies were detected using an indirect immunofluorescent test in the circulation of 100% of the 62 patients with clinical trichinellosis and 46% of the 39 patients with suspected exposure. The presence of antibodies specific to excretory-secretory products of T. spiralis muscle larvae was confirmed in the majority of the samples tested by a monoclonal antibody-based competitive inhibition assay. These results indicate that antibody detection is a more sensitive diagnostic method for human trichinellosis, but that antigen detection might be a useful confirmatory test because it is a direct demonstration of parasite products in the circulation
Water Pollution Detection Based on Hypothesis Testing in Sensor Networks
Directory of Open Access Journals (Sweden)
Xu Luo
2017-01-01
Full Text Available Water pollution detection is of great importance in water conservation. In this paper, the water pollution detection problems of the network and of the node in sensor networks are discussed. The detection problems in both cases of the distribution of the monitoring noise being normal and nonnormal are considered. The pollution detection problems are analyzed based on hypothesis testing theory firstly; then, the specific detection algorithms are given. Finally, two implementation examples are given to illustrate how the proposed detection methods are used in the water pollution detection in sensor networks and prove the effectiveness of the proposed detection methods.
Detection Test for Leakage of CO2 into Sodium Loop
International Nuclear Information System (INIS)
Park, Sun Hee; Wi, Myung-Hwan; Min, Jae Hong
2015-01-01
This report is about the facility for the detection test for leakage of CO 2 into sodium loop. The facility for the detection test for leakage of CO 2 into sodium loop was introduced. The test will be carried out. Our experimental results are going to be expected to be used for approach methods to detect CO 2 leaking into sodium in heat exchangers. A sodium-and-carbon dioxide (Na-CO 2 ) heat exchanger is one of the key components for the supercritical CO 2 Brayton cycle power conversion system of sodium-cooled fast reactors (SFRs). A printed circuit heat exchanger (PCHE) is considered for the Na-CO 2 heat exchanger, which is known to have potential for reducing the volume occupied by the exchangers compared to traditional shell-and-tube heat exchangers. Among various issues about the Na- CO 2 exchanger, detection of CO 2 leaking into sodium in the heat exchanger is most important thing for its safe operation. It is known that reaction products from sodium and CO 2 such as sodium carbonate (Na 2 CO 3 ) and amorphous carbon are hardly soluble in sodium, which cause plug sodium channels. Detection technique for Na 2 CO 3 in sodium loop has not been developed yet. Therefore, detection of CO 2 and CO from reaction of sodium and CO 2 are proper to detect CO 2 leakage into sodium loop
Proof-testing strategies induced by dangerous detected failures of safety-instrumented systems
International Nuclear Information System (INIS)
Liu, Yiliu; Rausand, Marvin
2016-01-01
Some dangerous failures of safety-instrumented systems (SISs) are detected almost immediately by diagnostic self-testing as dangerous detected (DD) failures, whereas other dangerous failures can only be detected by proof-testing, and are therefore called dangerous undetected (DU) failures. Some items may have a DU- and a DD-failure at the same time. After the repair of a DD-failure is completed, the maintenance team has two options: to perform an insert proof test for DU-failure or not. If an insert proof test is performed, it is necessary to decide whether the next scheduled proof test should be postponed or performed at the scheduled time. This paper analyzes the effects of different testing strategies on the safety performance of a single channel of a SIS. The safety performance is analyzed by Petri nets and by approximation formulas and the results obtained by the two approaches are compared. It is shown that insert testing improves the safety performance of the channel, but the feasibility and cost of the strategy may be a hindrance to recommend insert testing. - Highlights: • Identify the tests induced by detected failures. • Model the testing strategies following DD-failures. • Propose analytical formulas for effects of strategies. • Simulate and verify the proposed models.
Quench detection electronics testing protocol for SST-1 magnets
International Nuclear Information System (INIS)
Banaudha, Moni; Varmora, Pankaj; Parghi, Bhadresh; Prasad, Upendra
2017-01-01
Quench Detection (QD) system consisting 204 signal channels has been successfully installed and working well during plasma experiment of SST-1 Tokamak. QD system requires testing, validation and maintenance in every SST-1 campaign for better reliability and maintainability of the system. Standalone test of each channel of the system is essential for hard-ware validation. The standard Testing Protocol follow in every campaign which validate each section of QD electronics as well as voltage tap signal cables which are routed inside the cryostat and then extended outside of the SST-1 machine up-to the magnet control room. Fiber link for Quench signal transmission to the SST-1 magnet power supply is also test and validate before every plasma campaign. Precise instrument used as a dummy source of quench signal and for manual quench generation to test the each channel and Master Quench Logic. Each signal Integrated with the magnet DAQ system, signal observed at 1Hz and 50Hz configuration to validate the logging data, compare with actual and previous test data. This paper describes the testing protocol follow in every campaign to validate functionality of QD electronics, limitation of testing, test results and overall integration of the quench detection system for SST-1 magnet. (author)
Imperfection detection probability at ultrasonic testing of reactor vessels
International Nuclear Information System (INIS)
Kazinczy, F. de; Koernvik, L.Aa.
1980-02-01
The report is a lecture given at a symposium organized by the Swedish nuclear power inspectorate on February 1980. Equipments, calibration and testing procedures are reported. The estimation of defect detection probability for ultrasonic tests and the reliability of literature data are discussed. Practical testing of reactor vessels and welded joints are described. Swedish test procedures are compared with other countries. Series of test data for welded joints of the OKG-2 reactor are presented. Future recommendations for testing procedures are made. (GBn)
[Blood Test Patterns for Blood Donors after Nucleic Acid Detection in the Blood Center].
Men, Shou-Shan; Lv, Lian-Zhi; Chen, Yuan-Feng; Han, Chun-Hua; Liu, Hong-Yu; Yan, Yan
2017-12-01
To investigate the blood test patterns for blood donors after nucleic acid detection in blood center. The collected blood samples after voluntary blood donors first were detected by conventional ELISA, then 31981 negative samples were detected via HBV/HCV/HIV combined nucleic acid test of 6 mixed samples(22716 cases) or single samples(9265 cases) by means of Roche cobas s201 instrument. The combined detection method as follows: the blood samples were assayed by conventional nucleic acid test of 6 mixed samples, at same time, 6 mixed samples were treated with polyethylene glycol precipitation method to concentrate the virus, then the nucleic acid test of blood samples was performed; the single detection method as follows: firstly the conventional nucleic acid test of single sample was performed, then the positive reactive samples after re-examination were 6-fold diluted to simulate the nucleic acid test of 6-mixed samples. The positive rate of positive samples detected by combined nucleic acid test, positive samples detected by nucleic acid test of mixed virus concentration and positive samples detected by single nucleic acid test was statistically analyzed. In addition, for HBV + persons the serological test yet should be performed. In 22 716 samples detected by nucleic acid test of 6 mixed samples (MP-6-NAT) , 9 cases were HBV + (0.40‰, 9/22716); at same time, the detection of same samples by nucleic acid test of mixed sample virus concentration showed 29 cases of HBV + (1.28‰, 29/22716). In 9265 samples detected by single nucleic acid test(ID-NAT) 12 cases showed HBV + (1.30‰, 12/9265), meanwhile the detection of these 12 samples with HBV + by 6-fold dilution for virus concentration found only 4 samples with HBV + . In serological qualified samples, ID-NAT unqualified rate was 1.28‰, which was higher than that of MP-6-NAT(0.4‰) (χ 2 =8.11, P0.05). In 41 samples with HBsAg - HBV DNA + detected by ELISA, 36 samples were confirmed to be occult HBV
A pdf-Free Change Detection Test Based on Density Difference Estimation.
Bu, Li; Alippi, Cesare; Zhao, Dongbin
2018-02-01
The ability to detect online changes in stationarity or time variance in a data stream is a hot research topic with striking implications. In this paper, we propose a novel probability density function-free change detection test, which is based on the least squares density-difference estimation method and operates online on multidimensional inputs. The test does not require any assumption about the underlying data distribution, and is able to operate immediately after having been configured by adopting a reservoir sampling mechanism. Thresholds requested to detect a change are automatically derived once a false positive rate is set by the application designer. Comprehensive experiments validate the effectiveness in detection of the proposed method both in terms of detection promptness and accuracy.
Forsey, T; Darougar, S
1980-02-01
A rapid indirect micro-immunofluorescence test capable of detecting and differentiating type-specific antibodies to herpes simplex virus is described. The test proved highly sensitive and, in 80 patients with active herpes ocular infection, antibody was detected in 94%. No anti-herpes antibody was detected in a control group of 20 patients with adenovirus infections. Testing of animal sera prepared against herpes simplex virus types 1 and 2 and of human sera from cases of ocular and genital herpes infections showed that the test can differentiate antibodies to the infecting serotypes. Specimens of whole blood, taken by fingerprick, and eye secretions, both collected on cellulose sponges, could be tested by indirect micro-immunofluorescence. Anti-herpes IgG, IgM, and IgA can also be detected.
Field test of a leak detection system: planning, execution and results
Energy Technology Data Exchange (ETDEWEB)
Sampaio da Silva; Daniel; Melo Filho, Silvio A.; Niehues de Farias, Mauro; Pacheco, Anderson [Petrobas Transporte SA - TRANSPETRO, (Brazil)
2010-07-01
The OLAPA pipeline (Brazil) with its 97.6 km in length crosses difficult environment with a combination of mountain and dense forest. The non-detection of leaks in this kind of pipeline would have serious consequences. This pipeline was chosen for testing the performance of a new TRANSPETRO leak detection system. This paper reports the testing process of the new leakage detection method carried out on the OLAPA pipeline. TRANSPETRO decided to test the leakwarn system which is a computational pipeline monitoring (CPM) method which and can be integrated into their SCADA system. The CPM uses the mass balance principle with line pack change to analyze the pipeline operational parameters. The tests consisted of comparing the theoretical results with in-field results of alarm times obtained from controlled removal of product, simulating a real leak. Three leaks were tested in different states of operation and size of leak. It was found that the results were compatible with the expected alarm time.
Multianalyte Tests for the Early Detection of Cancer: Speedbumps and Barriers
Directory of Open Access Journals (Sweden)
Michael A. Tainsky
2007-01-01
Full Text Available It has become very clear that a single molecular event is inadequate to accurately predict the biology (or pathophysiology of cancer. Furthermore, using any single molecular event as a biomarker for the early detection of malignancy may not comprehensively identify the majority of individuals with that disease. Therefore, the fact that technologies have arisen that can simultaneously detect several, possibly hundreds, of biomarkers has propelled the field towards the development of multianalyte-based in vitro diagnostic early detection tests for cancer using body fl uids such as serum, plasma, sputum, saliva, or urine. These multianalyte tests may be based on the detection of serum autoantibodies to tumor antigens, the presence of cancer-related proteins in serum, or the presence of tumor-specific genomic changes that appear in plasma as free DNA. The implementation of non-invasive diagnostic approaches to detect early stage cancer may provide the physician with evidence of cancer, but the question arises as to how the information will affect the pathway of clinical intervention. The confirmation of a positive result from an in vitro diagnostic cancer test may involve relatively invasive procedures to establish a true cancer diagnosis. If in vitro diagnostic tests are proven to be both specific, i.e. rarely produce false positive results due to unrelated conditions, and sufficiently sensitive, i.e. rarely produce false negative results, then such screening tests offer the potential for early detection and personalized therapeutics using multiple disease-related targets with convenient and non-invasive means. Here we discuss the technical and regulatory barriers inherent in development of clinical multianalyte biomarker assays.
High sensitive quench detection method using an integrated test wire
International Nuclear Information System (INIS)
Fevrier, A.; Tavergnier, J.P.; Nithart, H.; Kiblaire, M.; Duchateau, J.L.
1981-01-01
A high sensitive quench detection method which works even in the presence of an external perturbing magnetic field is reported. The quench signal is obtained from the difference in voltages at the superconducting winding terminals and at the terminals at a secondary winding strongly coupled to the primary. The secondary winding could consist of a ''zero-current strand'' of the superconducting cable not connected to one of the winding terminals or an integrated normal test wire inside the superconducting cable. Experimental results on quench detection obtained by this method are described. It is shown that the integrated test wire method leads to efficient and sensitive quench detection, especially in the presence of an external perturbing magnetic field
Real time risk analysis of kick detection: Testing and validation
International Nuclear Information System (INIS)
Islam, Rakibul; Khan, Faisal; Venkatesan, Ramchandran
2017-01-01
Oil and gas development is moving into harsh and remote locations where the highest level of safety is required. A blowout is one of the most feared accidents in oil and gas developments projects. The main objective of this paper is to test and validate the kick detection of blowout risk assessment model using uniquely developed experimental results. Kick detection is a major part of the blowout risk assessment model. The accuracy and timeliness of kick detection are dependent on the monitoring of multiple downhole parameters such as downhole pressure, fluid density, fluid conductivity and mass flow rate. In the present study these four parameters are considered in different logical combinations to assess the occurrence of kick and associated blowout risk. The assessed results are compared against the experimental observations. It is observed that simultaneous monitoring of mass flow rate combined with any one the three parameters provides most reliable detection of kick and potential blowout likelihood. The current work presents the framework for a dynamic risk assessment and management model. Upon success testing of this approach at the pilot and field levels, this approach could provide a paradigm shift in drilling safety. - Highlights: • A novel dynamic risk model of kick detection and blowout prediction. • Testing and Validation of the risk model. • Application of the dynamic risk model.
A versatile omnibus test for detecting mean and variance heterogeneity.
Cao, Ying; Wei, Peng; Bailey, Matthew; Kauwe, John S K; Maxwell, Taylor J
2014-01-01
Recent research has revealed loci that display variance heterogeneity through various means such as biological disruption, linkage disequilibrium (LD), gene-by-gene (G × G), or gene-by-environment interaction. We propose a versatile likelihood ratio test that allows joint testing for mean and variance heterogeneity (LRT(MV)) or either effect alone (LRT(M) or LRT(V)) in the presence of covariates. Using extensive simulations for our method and others, we found that all parametric tests were sensitive to nonnormality regardless of any trait transformations. Coupling our test with the parametric bootstrap solves this issue. Using simulations and empirical data from a known mean-only functional variant, we demonstrate how LD can produce variance-heterogeneity loci (vQTL) in a predictable fashion based on differential allele frequencies, high D', and relatively low r² values. We propose that a joint test for mean and variance heterogeneity is more powerful than a variance-only test for detecting vQTL. This takes advantage of loci that also have mean effects without sacrificing much power to detect variance only effects. We discuss using vQTL as an approach to detect G × G interactions and also how vQTL are related to relationship loci, and how both can create prior hypothesis for each other and reveal the relationships between traits and possibly between components of a composite trait.
Testing the system detection unit for measuring solid minerals bulk density
Voytyuk, I. N.; Kopteva, A. V.
2017-10-01
The paper provides a brief description of the system for measuring flux per volume of solid minerals via example of mineral coal. The paper discloses the operational principle of the detection unit. The paper provides full description of testing methodology, as well as practical implementation of the detection unit testing. This paper describes the removal of two data arrays via the channel of scattered anddirect radiation for the detection units of two generations. This paper describes Matlab software to determine the statistical characteristics of the studied objects. The mean value of pulses per cycles, and pulse counting inaccuracy relatively the mean value were determined for the calculation of the stability account of the detection units.
Scintillating anticoincidence detection elements design and tests with muons and protons
International Nuclear Information System (INIS)
Gilliot, M.; Chabaud, J.; Baronick, J.P.; Colonges, S.; Laurent, P.
2010-01-01
Design, construction and tests of anticoincidence detection elements are presented. Initially planned to be used as active shielding parts of the anticoincidence detector of the Simbol-X mission, they are aimed to detect cosmic protons and provide veto signal against charged-particle background induced on imaging detectors. The sample is made of a scintillator plate into which grooves are machined and waveshifting fibers glued. The fibers are connected to multianode photomultiplier (PM) tubes. The tubes characteristics have been evaluated for this application. The device has been tested with atmospheric muons that deposit similar energy to that of cosmic protons thanks to a specially designed muon telescope also described in this paper. Tests have also been performed with protons of a tandem accelerator beam line. The response is on average above 10 photoelectrons, which is not complicated to detect, which allows very good detection efficiency as well as very good ability to reject noise. In addition many evolution and performance improvements appear possible.
Scintillating anticoincidence detection elements design and tests with muons and protons
Gilliot, M.; Chabaud, J.; Baronick, J. P.; Colonges, S.; Laurent, P.
2010-09-01
Design, construction and tests of anticoincidence detection elements are presented. Initially planned to be used as active shielding parts of the anticoincidence detector of the Simbol-X mission, they are aimed to detect cosmic protons and provide veto signal against charged-particle background induced on imaging detectors. The sample is made of a scintillator plate into which grooves are machined and waveshifting fibers glued. The fibers are connected to multianode photomultiplier (PM) tubes. The tubes characteristics have been evaluated for this application. The device has been tested with atmospheric muons that deposit similar energy to that of cosmic protons thanks to a specially designed muon telescope also described in this paper. Tests have also been performed with protons of a tandem accelerator beam line. The response is on average above 10 photoelectrons, which is not complicated to detect, which allows very good detection efficiency as well as very good ability to reject noise. In addition many evolution and performance improvements appear possible.
Scintillating anticoincidence detection elements design and tests with muons and protons
Energy Technology Data Exchange (ETDEWEB)
Gilliot, M., E-mail: mickael.gilliot@univ-reims.f [Laboratoire APC, AstroParticules and Cosmologie, Batiment Condorcet, 10 rue Alice Domont et Leonie Duquet, 75205 Paris Cedex 13 (France); Chabaud, J.; Baronick, J.P.; Colonges, S. [Laboratoire APC, AstroParticules and Cosmologie, Batiment Condorcet, 10 rue Alice Domont et Leonie Duquet, 75205 Paris Cedex 13 (France); Laurent, P. [Laboratoire APC, AstroParticules and Cosmologie, Batiment Condorcet, 10 rue Alice Domont et Leonie Duquet, 75205 Paris Cedex 13 (France); CEA/DSM/Irfu/SAp, CEA/Saclay, 91191 Gif-Sur-Yvette Cedex (France)
2010-09-21
Design, construction and tests of anticoincidence detection elements are presented. Initially planned to be used as active shielding parts of the anticoincidence detector of the Simbol-X mission, they are aimed to detect cosmic protons and provide veto signal against charged-particle background induced on imaging detectors. The sample is made of a scintillator plate into which grooves are machined and waveshifting fibers glued. The fibers are connected to multianode photomultiplier (PM) tubes. The tubes characteristics have been evaluated for this application. The device has been tested with atmospheric muons that deposit similar energy to that of cosmic protons thanks to a specially designed muon telescope also described in this paper. Tests have also been performed with protons of a tandem accelerator beam line. The response is on average above 10 photoelectrons, which is not complicated to detect, which allows very good detection efficiency as well as very good ability to reject noise. In addition many evolution and performance improvements appear possible.
Samsung Salmonella Detection Kit. AOAC Performance Tested Method(SM) 021203.
Li, Jun; Cheung, Win Den; Opdyke, Jason; Harvey, John; Chong, Songchun; Moon, Cheol Gon
2012-01-01
Salmonella, one of the most common causes of foodborne illness, is a significant public health concern worldwide. There is a need in the food industry for methods that are simple, rapid, and sensitive for the detection of foodborne pathogens. In this study, the Samsung Salmonella Detection Kit, a real-time PCR assay for the detection of Salmonella, was evaluated according to the current AOAC guidelines. The validation consisted of lot-to-lot consistency, stability, robustness, and inclusivity/exclusivity studies, as well as a method comparison of 10 different food matrixes. In the validation, the Samsung Salmonella Detection Kit was used in conjunction with the Applied Biosystems StepOnePlus PCR system and the Samsung Food Testing Software for the detection of Salmonella species. The performance of the assays was compared to the U.S. Department of Agriculture/Food Safety and Inspection Service-Microbiology Laboratory Guidebook (USDA/FSIS-MLG) 4.05: Isolation and Identification of Salmonella from Meat, Poultry, Pasteurized Egg, and Catfish and the and U.S. Food and Drug Administration/Bacteriological Analytical Manual (FDA/BAM) Chapter 5 Salmonella reference methods. The validation was conducted using an unpaired study design for detection of Salmonella spp. in raw ground beef, raw pork, raw ground pork, raw chicken wings, raw salmon, alfalfa sprouts, pasteurized orange juice, peanut butter, pasteurized whole milk, and shell eggs. The Samsung Salmonella Detection Kit demonstrated lot-to-lot consistency among three independent lots as well as ruggedness with minor modifications to changes in enrichment incubation time, enrichment incubation temperature, and DNA sample volume for PCR reaction. Stability was observed for 13 months at -20 degrees C and 3 months at 5 degrees C. For the inclusivity/exclusivity study, the Samsung Salmonella Detection Kit correctly identified 147 Salmonella species isolates out of 147 isolates tested from each of three different enrichment
Hypothesis tests for the detection of constant speed radiation moving sources
Energy Technology Data Exchange (ETDEWEB)
Dumazert, Jonathan; Coulon, Romain; Kondrasovs, Vladimir; Boudergui, Karim; Sannie, Guillaume; Gameiro, Jordan; Normand, Stephane [CEA, LIST, Laboratoire Capteurs Architectures Electroniques, 99 Gif-sur-Yvette, (France); Mechin, Laurence [CNRS, UCBN, Groupe de Recherche en Informatique, Image, Automatique et Instrumentation de Caen, 4050 Caen, (France)
2015-07-01
Radiation Portal Monitors are deployed in linear network to detect radiological material in motion. As a complement to single and multichannel detection algorithms, inefficient under too low signal to noise ratios, temporal correlation algorithms have been introduced. Test hypothesis methods based on empirically estimated mean and variance of the signals delivered by the different channels have shown significant gain in terms of a tradeoff between detection sensitivity and false alarm probability. This paper discloses the concept of a new hypothesis test for temporal correlation detection methods, taking advantage of the Poisson nature of the registered counting signals, and establishes a benchmark between this test and its empirical counterpart. The simulation study validates that in the four relevant configurations of a pedestrian source carrier under respectively high and low count rate radioactive background, and a vehicle source carrier under the same respectively high and low count rate radioactive background, the newly introduced hypothesis test ensures a significantly improved compromise between sensitivity and false alarm, while guaranteeing the stability of its optimization parameter regardless of signal to noise ratio variations between 2 to 0.8. (authors)
Evaluation of the White Test for the Intraoperative Detection of Bile Leakage
Leelawat, Kawin; Chaiyabutr, Kittipong; Subwongcharoen, Somboon; Treepongkaruna, Sa-ad
2012-01-01
We assess whether the White test is better than the conventional bile leakage test for the intraoperative detection of bile leakage in hepatectomized patients. This study included 30 patients who received elective liver resection. Both the conventional bile leakage test (injecting an isotonic sodium chloride solution through the cystic duct) and the White test (injecting a fat emulsion solution through the cystic duct) were carried out in the same patients. The detection of bile leakage was c...
Detection at a distance of atomic bomb tests
Energy Technology Data Exchange (ETDEWEB)
Nahmias, M E
1954-01-01
Nahmias describes the radioassay of air, rain, and snowfall as the basis for detecting atomic bomb tests. Tables and graphs give time vs. Ra equivalents, distance vs Roentgens/h of radiation, and distribution of radioelements which can be expected.
Li, Lishu; Ikezono, Tetsuo; Sekine, Kuwon; Shindo, Susumu; Matsumura, Tomohiro; Pawankar, Ruby; Ichimiya, Issei; Yagi, Toshiaki
2010-08-01
We have cloned guinea pig Coch cDNA and the sequence information will be useful for future molecular study combined with physiological experiments. Proper Coch gene expression appears to be dependent on the unique extracellular micro-environment of the inner ear in vivo. These results provide insight into the Coch gene expression and its regulation. To characterize the guinea pig Coch gene, we performed molecular cloning and expression analysis in the inner ear and cultured fibrocytes of the spiral ligament. The Coch cDNA was isolated using RACE. Cochlin isofoms were studied by Western blot using three different types of mammalian inner ear. The cochlear fibrocytes were cultured and characterized by immunostaining. Coch gene expression in the fibrocytes was investigated and the influence of cytokine stimulation was evaluated. The full-length 1991 bp Coch cDNA that encodes a 553 amino acid protein was isolated. The sequence had significant homology with other mammals, and the sizes of the Cochlin isoforms were identical. In the cultured fibrocytes, Coch mRNA was expressed in a very small amount and the isoform production was different, compared with the results in vivo. Cytokine stimulation did not alter the level of mRNA expression or isoform formation.
Detection of ductile crack initiation by acoustic emission testing
International Nuclear Information System (INIS)
Richter, H.; Boehmert, J.; Viehrig, H.W.
1998-08-01
A Charpy impact test equipment is described permitting simultaneous measurement of impact force, crack tip opening, acoustic emissions and magnetic emissions. The core of the equipment is an inverted pendulum ram impact testing machine and the tests have been performed with laterally notched, pre-fatigue ISO-V specimens made of steels of various strength and toughness properties. The tests are intended to ascertain whether the acoustic emission method is suitable for detecting steady crack initiation in highly ductile steels. (orig./CB) [de
Advantages and disadvantages of current diagnostic tests for the detection of Helicobacter pylori.
Mégraud, F
1996-01-01
Current tests used to detect Helicobacter pylori are either invasive (histological detection, culture, the polymerase chain reaction (PCR), smear examination) or non-invasive (serology, 13C-urea breath test). These tests vary in their sensitivity and specificity, and the choice of test will depend on the situation, for example, whether the test is to detect infection or the success of eradication treatment. The accuracy of histological tests depends, to a large degree, on the expertise of the pathologist, while the accuracy of culture can depend on the conditions in which the specimen is transported and processed. When performed under optimal conditions, both techniques give very good results. The PCR test has similar sensitivity and specificity to histological and culture tests but a strict protocol must be followed to avoid contamination with H. pylori DNA. The rapid urease test (with a reading taken 1 hour later) is suitable for diagnosis before treatment but its sensitivity decreases after treatment. Smear examination has limited sensitivity. The urea breath test and serology (specific IgG detected by enzyme-linked immunosorbent assay with purified antigens) have sensitivities close to those using the best of the biopsy methods. Other points to consider when selecting a test are its availability, the rapidity of the results (which can range from a few minutes to 2 weeks), possibilities for retrospective analysis, quantification and the detection of pathogenic properties, the globality of certain tests that present an overall picture of the stomach, thus avoiding errors in sampling, and the cost of the test. Important added value can be gained from certain tests: histology allows evaluation of the status of the mucosa, culture allows strain typing and tests for antibiotic susceptibility, and the breath test can confirm successful eradication without endoscopy. When the diagnostic tests are performed correctly, most of them are highly accurate.
Application of Bayesian Methods for Detecting Fraudulent Behavior on Tests
Sinharay, Sandip
2018-01-01
Producers and consumers of test scores are increasingly concerned about fraudulent behavior before and during the test. There exist several statistical or psychometric methods for detecting fraudulent behavior on tests. This paper provides a review of the Bayesian approaches among them. Four hitherto-unpublished real data examples are provided to…
International Nuclear Information System (INIS)
Mettenboerger, D.; Vith, E.
1982-01-01
Methods of application of the direct and indirect haemolysis inhibition test were studied in order to optimise the test parameters: The ultimate aim was to standardize the test method and compare its sensitivity in detecting various platelet antibodies with platelet indirect radioactive Coombs-test and the platelet immunofluorescence test. (orig.) [de
An Optical Test Strip for the Detection of Benzoic Acid in Food
Directory of Open Access Journals (Sweden)
Fatimah Abu Bakar
2011-07-01
Full Text Available Fabrication of a test strip for detection of benzoic acid was successfully implemented by immobilizing tyrosinase, phenol and 3-methyl-2-benzothiazolinone hydrazone (MBTH onto filter paper using polystyrene as polymeric support. The sensing scheme was based on the decreasing intensity of the maroon colour of the test strip when introduced into benzoic acid solution. The test strip was characterized using optical fiber reflectance and has maximum reflectance at 375 nm. It has shown a highly reproducible measurement of benzoic acid with a calculated RSD of 0.47% (n = 10. The detection was optimized at pH 7. A linear response of the biosensor was obtained in 100 to 700 ppm of benzoic acid with a detection limit (LOD of 73.6 ppm. At 1:1 ratio of benzoic acid to interfering substances, the main interfering substance is boric acid. The kinetic analyses show that, the inhibition of benzoic is competitive inhibitor and the inhibition constant (Ki is 52.9 ppm. The activity of immobilized tyrosinase, phenol, and MBTH in the test strip was fairly sustained during 20 days when stored at 3 °C. The developed test strip was used for detection of benzoic acid in food samples and was observed to have comparable results to the HPLC method, hence the developed test strip can be used as an alternative to HPLC in detecting benzoic acid in food products.
Optical generation,detection and non-destructive testing applications of terahertz waves
Institute of Scientific and Technical Information of China (English)
ZHANG; Weili; LIANG; Dachuan; TIAN; Zhen; HAN; Jiaguang; GU; Jianqiang; HE; Mingxia; OUYANG; Chunmei
2016-01-01
Optoelectronic terahertz generation and detection play a key role in the applications of non-destructive testing,which involves different areas such as physics,biological,material science,imaging,explosions detection,astronomy applications,semiconductor technology and superconductiong electronics. In this article,we present a reviewof the principle and performance of typical terahertz sources,detectors and non-destructive testing applications. On this basis,the newdevelopment and trends of terahertz radiation detectors are also discussed.
[Rapid test for detection of susceptibility to cefotaxime in Enterobacteriaceae].
Jiménez-Guerra, Gemma; Hoyos-Mallecot, Yannik; Rodríguez-Granger, Javier; Navarro-Marí, José María; Gutiérrez-Fernández, José
In this work an "in house" rapid test based on the change in pH that is due to hydrolysis for detecting Enterobacteriaceae susceptible to cefotaxime is evaluated. The strains of Enterobacteriaceae from 1947 urine cultures were assessed using MicroScan panels and the "in house" test. This rapid test includes red phenol solution and cefotaxime. Using MicroScan panels, 499 Enterobacteriaceae isolates were evaluated, which included 27 isolates of Escherichia coli producing extended-spectrum beta-lactamases (ESBL), 16 isolates of Klebsiella pneumoniae ESBL and 1 isolate of Klebsiella oxytoca ESBL. The "in house" test offers the following values: sensitivity 98% and specificity 97%, with negative predictive value 100% and positive predictive value 78%. The "in house" test based on the change of pH is useful in our area for detecting presumptively cefotaxime-resistant Enterobacteriaceae strains. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.
9 CFR 113.36 - Detection of pathogens by the chicken inoculation test.
2010-01-01
... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of pathogens by the chicken... REQUIREMENTS Standard Procedures § 113.36 Detection of pathogens by the chicken inoculation test. The test for...,000 doses. (b) At least 25 healthy susceptible young chickens, properly identified and obtained from...
Explosive simulants for testing explosive detection systems
Kury, John W.; Anderson, Brian L.
1999-09-28
Explosives simulants that include non-explosive components are disclosed that facilitate testing of equipment designed to remotely detect explosives. The simulants are non-explosive, non-hazardous materials that can be safely handled without any significant precautions. The simulants imitate real explosives in terms of mass density, effective atomic number, x-ray transmission properties, and physical form, including moldable plastics and emulsions/gels.
Minimum detection efficiencies for a loophole-free observable-asymmetric Bell-type test
International Nuclear Information System (INIS)
Garbarino, G.
2010-01-01
We discuss the problem of finding the most favorable conditions for closing the detection loophole in a test of local realism with a Bell inequality. For a generic nonmaximally entangled two-qubit state and two incompatible bases to be adopted for alternative measurements of two observables a and b on each party, we apply Hardy's proof of nonlocality without inequality and derive an Eberhard-like inequality. For an infinity of nonmaximally entangled states we find that it is possible to refute local realism by requiring perfect detection efficiency for only one of the two observables, say b, to be measured on each party: The test is free from the detection loophole for any value of the detection efficiency corresponding to the other observable a. The maximum tolerable noise in such a loophole-free observable-asymmetric test is also evaluated.
Hall, Steven R.; Walker, Bruce K.
1990-01-01
A new failure detection and isolation algorithm for linear dynamic systems is presented. This algorithm, the Orthogonal Series Generalized Likelihood Ratio (OSGLR) test, is based on the assumption that the failure modes of interest can be represented by truncated series expansions. This assumption leads to a failure detection algorithm with several desirable properties. Computer simulation results are presented for the detection of the failures of actuators and sensors of a C-130 aircraft. The results show that the OSGLR test generally performs as well as the GLR test in terms of time to detect a failure and is more robust to failure mode uncertainty. However, the OSGLR test is also somewhat more sensitive to modeling errors than the GLR test.
Detection Test for Leakage of CO{sub 2} into Sodium Loop
Energy Technology Data Exchange (ETDEWEB)
Park, Sun Hee; Wi, Myung-Hwan; Min, Jae Hong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2015-10-15
This report is about the facility for the detection test for leakage of CO{sub 2} into sodium loop. The facility for the detection test for leakage of CO{sub 2} into sodium loop was introduced. The test will be carried out. Our experimental results are going to be expected to be used for approach methods to detect CO{sub 2} leaking into sodium in heat exchangers. A sodium-and-carbon dioxide (Na-CO{sub 2}) heat exchanger is one of the key components for the supercritical CO{sub 2} Brayton cycle power conversion system of sodium-cooled fast reactors (SFRs). A printed circuit heat exchanger (PCHE) is considered for the Na-CO{sub 2} heat exchanger, which is known to have potential for reducing the volume occupied by the exchangers compared to traditional shell-and-tube heat exchangers. Among various issues about the Na- CO{sub 2} exchanger, detection of CO{sub 2} leaking into sodium in the heat exchanger is most important thing for its safe operation. It is known that reaction products from sodium and CO{sub 2} such as sodium carbonate (Na{sub 2}CO{sub 3}) and amorphous carbon are hardly soluble in sodium, which cause plug sodium channels. Detection technique for Na{sub 2}CO{sub 3} in sodium loop has not been developed yet. Therefore, detection of CO{sub 2} and CO from reaction of sodium and CO{sub 2} are proper to detect CO{sub 2} leakage into sodium loop.
Comparison of four urease-dependent tests of detecting HP infection
International Nuclear Information System (INIS)
Han Yuan; Huang Gang; Zhu Cuiying; Ling Liqun
2001-01-01
Objective: The aim of this study is to compare the four urease-dependent tests of detecting Hp infection. The authors used following method: 1) rapid urease test (RUT), 2) 14 C urea breath test ( 14 C-UBT), 3) 13 C urea breath test which is measured by with infrared spectrometry ( 13 C-UBT1), 4) 13 C urea breath test with mass spectrometry ( 13 C-UBT). Methods: 54 patients underwent RUT, 14 C-UBT, 13 C-UBT1, 13 C-UBT2 respectively. Results: Sensitivity and specificity, accurate rate, positive predictive value (PPV), negative predictive value (NPV), respectively, were as follows: RUT (82.1%, 80%, 81.5%, 91.4%, 63.2%), 14 C-UBT (97.4%, 100%, 98.1%, 100%, 93.8%), 13 C-UBT1 (100%, 93.3%, 98.1%, 97.5%, 100%), 13 C-UBT2 (100%, 86.7%, 96.3%, 95.1%, 100%), PPV of four tests are not significantly different (P>0.05). Conclusion: Four urease-dependent tests are high sensitive and accurate methods for detecting Hp infection. UBT is an ideal tool for diagnosis, screen and follow-up of Hp infection
Executive cognitive impairment detected by simple bedside testing ...
African Journals Online (AJOL)
Aims. Cognitive impairment in people with type 2 diabetes is a barrier to successful disease management. We sought to determine whether impaired executive function as detected by a battery of simple bedside cognitive tests of executive function was associated with inadequate glycaemic control. Methods. People with ...
Experimental study on flaw detectability of remote field eddy current testing
International Nuclear Information System (INIS)
Kamimura, T.; Fukui, S.; Iwahashi, Y.; Yamada, H.
1988-01-01
For the purpose of comprehending the effect in practical use of the remote field eddy current (RFEC) testing that becomes noticeable for the ISI technique of steel tubes, its flaw detectability was clarified through a model test. This study used straight and bending tubes of 3.8 mm in wall thickness and 31.8 mm in outside diameter. These tubes were inspected from their inside. After relations among the pickup coil output, coil distance, testing frequency, etc. were measured, a probe of the practical use type was manufactured to investigate its flaw detectability by means of simulated flaws. The authors discuss how it has been found that light local wall thinning on the outside surfaces can be detected by this technique and its effect in practical use can be expected with small influences due to magnetic permeability variations of tube materials, bending of tubes, etc
Summary of accidental releases of radioactivity detected off the Nevada Test Site, 1963--1986
International Nuclear Information System (INIS)
Patzer, R.G.; Phillips, W.G.; Grossman, R.F.; Black, S.C.; Costa, C.F.
1988-08-01
Of the more than 450 underground nuclear explosives tests conducted at the Nevada Test Site from August 1963 (signing of the Limited Test Ban Treaty) through the end of 1986, only 23 accidentally released radioactivity that was detectable beyond the boundary of the NTS. Of these 23, 4 were detectable off the NTS only by aircraft while the remainder were detectable by ground monitoring instruments. Since the Baneberry venting of December 1970, only two tests released radioactivity that was detectable off the NTS, and this was a seepage of radioactive noble gases. None of these releases from underground tests designed for complete containment caused exposure of the population living in the area that exceeded standards recommended by national and international radiation protection agencies. This report summarizes the releases from each of the tests, describes the monitoring that was conducted, and lists the location of the maximum exposure
Bezos, Javier; Roy, Álvaro; Infantes-Lorenzo, José Antonio; González, Isabel; Venteo, Ángel; Romero, Beatriz; Grau, Anna; Mínguez, Olga; Domínguez, Lucas; de Juan, Lucía
2018-05-01
The diagnosis of tuberculosis (TB) in goats is based mainly on the single and comparative intradermal tuberculin (SIT and CIT) tests and, exceptionally, on the interferon-gamma (IFN-γ) assay, however they are not perfect in terms of sensitivity and specificity. Nevertheless, various serological assays that provide a potential cost-effective approach for the control of TB are also available or under development, and a variety of results have been reported regarding the ability of these tests to detect infected animals, particularly in the early stages of infection. In the present study, SIT/CIT and IFN-γ tests and three different serological assays were evaluated during two consecutive herd testing events in a recently infected caprine herd (n = 447) with a high prevalence of infection in order to evaluate their performance and provide field data with which to improve the TB control programs in this species. The proportion of infected animals that tested positive among all the infected goats (T+/I+ value) in the last herd testing event ranged from 26.2% (IC95%; 19.3-34.5) to 85.7% (IC95%; 78.5-90.7) using cell-based diagnostic tests. The SIT/SCIT tests detected more infected goats than the IFN-γ test, regardless of the interpretation criteria. The T+/I+ value of serology was 83.2 (IC95%; 75.2-89), although it increased significantly (P test (100%, IC95%; 97-100). In general, a parallel interpretation of intradermal tests with serology maximized the detection of infected goats. These results demonstrate that serological tests are valuable diagnostic tools to maximize the detection of TB infected goats, even in recent outbreaks, accelerating the eradication process. Copyright © 2018 Elsevier B.V. All rights reserved.
Field Test Data for Detecting Vibrations of a Building Using High-Speed Video Cameras
2017-10-01
ARL-TR-8185 ● OCT 2017 US Army Research Laboratory Field Test Data for Detecting Vibrations of a Building Using High-Speed Video...Field Test Data for Detecting Vibrations of a Building Using High-Speed Video Cameras by Caitlin P Conn and Geoffrey H Goldman Sensors and...June 2016 – October 2017 4. TITLE AND SUBTITLE Field Test Data for Detecting Vibrations of a Building Using High-Speed Video Cameras 5a. CONTRACT
Efficacy of immunoassay chromatography test for hepatitis-C antibodies detection
International Nuclear Information System (INIS)
Batool, A.; Khan, M.I.; Bano, K.A.
2009-01-01
To asses the efficacy of commercially available tests device method for anti HCV detection. Methods: Total 2000 blood samples for detection of anti HCV were screened initially by immuno chromatographic method. Those found positive on initial screening were re-tested by ELISA method at the Biochemistry Laboratory of the Pakistan Medical Research Council, Fatima Jinnah Medical College, Lahore. Results: Out of a total of 2,000 blood samples, 177 were found to be initially reactive/positive for anti-HCV with immuno chromatographic method. When these reactive/positive samples were retested for confirmation with ELISA, 47 blood samples were found to have tested falsely positive for anti-HCV. Overall 2.35% of blood samples were found to be tested false positive for anti-HCV by immuno chromatographic device method. Conclusions: Immuno chromatographic device method test is rapid and simple, which can be used in setting with limited facility when rapid testing is required. However it should not be used as sole criteria for diagnosis but should serve the purpose of initial screening only. Further research is required to establish the reliability of such devices for their specificity and sensitivity. (author)
Defect detectability of eddy current testing for underwater laser beam welding
International Nuclear Information System (INIS)
Ueno, Souichi; Kobayashi, Noriyasu; Ochiai, Makoto; Kasuya, Takashi; Yuguchi, Yasuhiro
2011-01-01
We clarified defect detectability of eddy current testing (ECT) as a surface inspection technique for underwater laser beam welding works of dissimilar metal welding (DMW) of reactor vessel nozzle. The underwater laser beam welding procedure includes groove caving as a preparation, laser beam welding in the grooves and welded surface grinding as a post treatment. Therefore groove and welded surface inspections are required in the underwater condition. The ECT is a major candidate as this inspection technique because a penetrant testing is difficult to perform in the underwater condition. Several kinds of experiments were curried out using a cross coil an ECT probe and ECT data acquisition system in order to demonstrate the ECT defect detectability. We used specimens, simulating groove and DMW materials at an RV nozzle, with electro-discharge machining (EDM) slits over it. Additionally, we performed a detection test for artificial stress corrosion cracking (SCC) defects. From these experimental results, we confirmed that an ECT was possible to detect EDM slits 0.3 mm or more in depth and artificial SCC defects 0.02 mm to 0.48 mm in depth on machined surface. Furthermore, the underwater ECT defect detectability is equivalent to that in air. We clarified an ECT is sufficiently usable as a surface inspection technique for underwater laser beam welding works. (author)
Statistical Methods for the detection of answer copying on achievement tests
Sotaridona, Leonardo
2003-01-01
This thesis contains a collection of studies where statistical methods for the detection of answer copying on achievement tests in multiple-choice format are proposed and investigated. Although all methods are suited to detect answer copying, each method is designed to address specific
Performance test of SKIROC II ASIC chip for the radiation detection
Energy Technology Data Exchange (ETDEWEB)
Jun, W. J.; Namgoong, H.; Kim, B. K.; Song, H. S.; Kim, H. S.; Lee, S. H.; Choi, H. J.; Ghergherehchi, M.; Chai, J. S. [Sungkyunkwan University, Suwon (Korea, Republic of)
2017-04-15
There is a PCB board called FEV8 board which can readout analog signal from any energy source, and amplify it for signal processing. For precise detection, the board had been designed to operate in wide range of energy condition, with high-resolutive detection performance. This function has the possibility of the utilization for the radiation detection. The channels of the prototype board must be evaluated to make sure that the board is perfect or not. This research had made an progress for the radiation detection as well as the electronics of the intricate combination of the measurement instrumentations. The number of the noisy channels had been measured for threshold scan, and every channels in the board had been evaluated. By improving the experimental conditions such as test script in Linux system or well designed ground condition of the test bench, much more clean data will be able to be acquisited.
A NOTE ON THE CONVENTIONAL OUTLIER DETECTION TEST PROCEDURES
Directory of Open Access Journals (Sweden)
JIANFENG GUO
Full Text Available Under the assumption of that the variance-covariance matrix is fully populated, Baarda's w-test is turn out to be completely different from the standardized least-squares residual. Unfortunately, this is not generally recognized. In the limiting case of only one degree of freedom, all the three types of test statistics, including Gaussian normal test, Student's t-test and Pope's Tau-test, will be invalid for identification of outliers: (1 all the squares of the Gaussian normal test statistic coincide with the goodness-of-fit (global test statistic, even for correlated observations. Hence, the failure of the global test implies that all the observations will be flagged as outliers, and thus the Gaussian normal test is inconclusive for localization of outliers; (2 the absolute values of the Tau-test statistic are all exactly equal to one, no matter whether the observations are contaminated. Therefore, the Tau-test cannot work for outlier detection in this situation; and (3 Student's t-test statistics are undefined.
PageFocus: Using paradata to detect and prevent cheating on online achievement tests.
Diedenhofen, Birk; Musch, Jochen
2017-08-01
Cheating threatens the validity of unproctored online achievement tests. To address this problem, we developed PageFocus, a JavaScript that detects when participants abandon test pages by switching to another window or browser tab. In a first study, we aimed at testing whether PageFocus could detect and prevent cheating. We asked 115 lab and 186 online participants to complete a knowledge test comprising items that were difficult to answer but easy to look up on the Internet. Half of the participants were invited to look up the solutions, which significantly increased their test scores. The PageFocus script detected test takers who abandoned the test page with very high sensitivity and specificity, and successfully reduced cheating by generating a popup message that asked participants not to cheat. In a second study, 510 online participants completed a knowledge test comprising items that could easily be looked up and a reasoning task involving matrices that were impossible to look up. In a first group, a performance-related monetary reward was promised to the top scorers; in a second group, participants took part in a lottery that provided performance-unrelated rewards; and in a third group, no incentive was offered. PageFocus revealed that participants cheated more when performance-related incentives were offered. As expected, however, this effect was limited to items that could easily be looked up. We recommend that PageFocus be routinely employed to detect and prevent cheating on online achievement tests.
Nadalin, Silvio; Li, Jun; Lang, Hauke; Sotiropoulos, Georgios C; Schaffer, Randolph; Radtke, Arnold; Saner, Fuat; Broelsch, Christoph E; Malagó, Massimo
2008-04-01
To describe a new intraoperative bile leakage test in patients undergoing a major liver resection aimed to combine the advantages of each of the other standard bile leakage tests (accurate visualization of leaks, reproducibility, and ease of use) without their disadvantages. At the end of the major hepatic resection, 10 to 30 mL of sterile fat emulsion, 5%, is injected via an olive-tip cannula through the cystic duct while manually occluding the distal common bile duct. As the biliary tree fills with fat emulsion solution, leakage of the white fluid is visualized on the raw surface of the liver resection margin. The detected leakages are closed by means of single stitches. Afterwards, the residual fat emulsion on the resection surface is washed off with saline and the White test is repeated to detect and/or exclude additional bile leakages. At the end, residual fat emulsion is washed out from the biliary tract by a low-pressure infusion of saline solution. Intraoperatively, additional potential bile leakages (not seen using a conventional saline bile leakage test) were identified in 74% of our patients. Postoperative bile leakages (within 30 days) occurred in only 5.1% of patients when the White test was used. No adverse effects related to this technique were observed. The White test has clear advantages in comparison with other bile leakage tests: it precisely detects bile leakages, regardless of size; it does not stain the resection surface, allowing it to be washed off and repeated ad infinitum; and it is safe, quick, and inexpensive.
Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool.
Mesquita, Flávio da Silva; Oliveira, Danielle Bruna Leal de; Crema, Daniela; Pinez, Célia Miranda Nunes; Colmanetti, Thaís Cristina; Thomazelli, Luciano Matsumia; Gilio, Alfredo Elias; Vieira, Sandra Elisabeth; Martinez, Marina Baquerizo; Botosso, Viviane Fongaro; Durigon, Edison Luiz
The aim of this study was to evaluate the QuickVue ® RSV Test Kit (QUIDEL Corp, CA, USA) as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue ® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. From 313 positive samples by immunofluorescence assays, 282 (90%) were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue ® RSV Test and viral load or specific strain. The QuickVue ® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. This study demonstrated that the QuickVue ® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.
Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool,
Directory of Open Access Journals (Sweden)
Flávio da Silva Mesquita
Full Text Available Abstract Objective: The aim of this study was to evaluate the QuickVue® RSV Test Kit (QUIDEL Corp, CA, USA as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. Methods: The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. Results: From 313 positive samples by immunofluorescence assays, 282 (90% were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue® RSV Test and viral load or specific strain. The QuickVue® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics.
Design and preliminary test results of the quench detection system for IFSMTF
International Nuclear Information System (INIS)
Shen, S.S.; Walstrom, P.L.; Wilson, C.T.; Goddard, J.S.
1985-01-01
A unique quench detection system was designed for the International Fusion Superconducting Magnet Test Facility (IFSMTF), where a simultaneous test of six large superconducting toroidal field magnets will be carried out. The scheme was based on analog subtraction of self and neighboring pickup winding voltage from the coil voltage to yield a compensated signal proportional to a normal-zone voltage. The compensated signals were input to quench detection modules that give a quench output signal to discharge the coil if the compensated signals exceed preset thresholds for preset time durations. This paper summarizes the design and analysis of the system and presents the experimental results of the simulation tests, two-coil charging-discharging tests, and the normal-zone recovery tests
Directory of Open Access Journals (Sweden)
Mohamed Ramadan El-Jade
Full Text Available Rapid detection and reporting of third generation cephalosporine resistance (3GC-R and of extended spectrum betalactamases in Enterobacteriaceae (ESBL-E is a diagnostic and therapeutic priority to avoid inefficacy of the initial antibiotic regimen. In this study we evaluated a commercially available chromogenic screen for 3GC-R as a predictive and/or confirmatory test for ESBL and AmpC activity in clinical and veterinary Enterobacteriaceae isolates. The test was highly reliable in the prediction of cefotaxime and cefpodoxime resistance, but there was no correlation with ceftazidime and piperacillin/tazobactam minimal inhibitory concentrations. All human and porcine ESBL-E tested were detected with exception of one genetically positive but phenotypically negative isolate. By contrast, AmpC detection rates lay below 30%. Notably, exclusion of piperacillin/tazobactam resistant, 3GC susceptible K1+ Klebsiella isolates increased the sensitivity and specificity of the test for ESBL detection. Our data further imply that in regions with low prevalence of AmpC and K1 positive E. coli strains chromogenic testing for 3GC-R can substitute for more time consuming ESBL confirmative testing in E. coli isolates tested positive by Phoenix or VITEK2 ESBL screen. We, therefore, suggest a diagnostic algorithm that distinguishes 3GC-R screening from primary culture and species-dependent confirmatory ESBL testing by βLACTATM and discuss the implications of MIC distribution results on the choice of antibiotic regimen.
[Validation of three screening tests used for early detection of cervical cancer].
Rodriguez-Reyes, Esperanza Rosalba; Cerda-Flores, Ricardo M; Quiñones-Pérez, Juan M; Cortés-Gutiérrez, Elva I
2008-01-01
to evaluate the validity (sensitivity, specificity, and accuracy) of three screening methods used in the early detection of the cervical carcinoma versus the histopathology diagnosis. a selected sample of 107 women attended in the Opportune Detection of Cervicouterine Cancer Program in the Hospital de Zona 46, Instituto Mexicano del Seguro Social in Durango, during the 2003 was included. The application of Papa-nicolaou, acetic acid test, and molecular detection of human papillomavirus, and histopatholgy diagnosis were performed in all the patients at the time of the gynecological exam. The detection and tipification of the human papillomavirus was performed by polymerase chain reaction (PCR) and analysis of polymorphisms of length of restriction fragments (RFLP). Histopathology diagnosis was considered the gold standard. The evaluation of the validity was carried out by the Bayesian method for diagnosis test. the positive cases for acetic acid test, Papanicolaou, and PCR were 47, 22, and 19. The accuracy values were 0.70, 0.80 and 0.99, respectively. since the molecular method showed a greater validity in the early detection of the cervical carcinoma we considered of vital importance its implementation in suitable programs of Opportune Detection of Cervicouterino Cancer Program in Mexico. However, in order to validate this conclusion, cross-sectional studies in different region of country must be carried out.
Sensitivity of the improved Dutch tube diffusion test for detection of ...
African Journals Online (AJOL)
The sensitivity of the improved two-tube test for detection of antimicrobial residues in Kenyan milk was investigated by comparison with the commercial Delvo test SP. Suspect positive milk samples (n =244) from five milk collection centers, were analyzed with the improved two-tube and the commercial Delvo SP test as per ...
Hermetic Seal Leak Detection Apparatus with Variable Size Test Chamber
Kelley, Anthony R. (Inventor)
2015-01-01
The present invention is a versatile hermetic seal leak detection apparatus for testing hermetically sealed containers and devices for leaks without the need to create a custom or specially manufactured testing chamber conforming to the dimensions of the specific object under test. The size of the testing chamber may be mechanically adjusted by the novel use of bellows to reduce and optimize the amount of gas space in a test chamber which surrounds the hermetically sealed object under test. The present invention allows the size of the test chamber to be selectively adjusted during testing to provide an optimum test chamber gas space. The present invention may be further adapted to isolate and test specific portions of the hermetically sealed object under test for leaks.
14C-urea breath test for the detection of Helicobacter pylori
International Nuclear Information System (INIS)
Veldhuyzen van Zanten, S.J.; Tytgat, K.M.; Hollingsworth, J.; Jalali, S.; Rshid, F.A.; Bowen, B.M.; Goldie, J.; Goodacre, R.L.; Riddell, R.H.; Hunt, R.H.
1990-01-01
The high urease activity of Helicobacter pylori can be used to detect this bacterium by noninvasive breath tests. We have developed a 14 C-urea breath test which uses 5 microCi 14 C with 50 mg nonradioactive urea. Breath samples are collected at baseline and every 30 min for 2 h. Our study compared the outcome of the breath test to the results of histology and culture of endoscopically obtained gastric biopsies in 84 patients. The breath test discriminated well between the 50 positive patients and the 34 patients negative for Helicobacter pylori: the calculated sensitivity was 100%, specificity 88%, positive predictive value 93%, and negative predictive value 100%. Treatment with bismuth subsalicylate and/or ampicillin resulted in lower counts of exhaled 14 CO 2 which correlated with histological improvement in gastritis. The 14 C-urea breath test is a better gold standard for the detection of Helicobacter pylori than histology and/or culture
The Stool DNA Test is More Accurate than the Plasma Septin 9 Test in Detecting Colorectal Neoplasia
Ahlquist, David A.; Taylor, William R.; Mahoney, Douglas W.; Zou, Hongzhi; Domanico, Michael; Thibodeau, Stephen N.; Boardman, Lisa A.; Berger, Barry M.; Lidgard, Graham P.
2014-01-01
Background & Aims Several noninvasive tests have been developed for colorectal cancer (CRC) screening. We compared the sensitivities of a multi-marker test for stool DNA (sDNA) and a plasma test for methylated Septin 9 (SEPT9) in identifying patients with large adenomas or CRC. Methods We analyzed paired stool and plasma samples from 30 patients with CRC and 22 with large adenomas from Mayo Clinic archives. Stool (n=46) and plasma (n=49) samples from age- and sex-matched patients with normal colonoscopy results were used as controls. The sDNA test is an assay for methylated BMP3, NDRG4, vimentin, and TFPI2; mutant KRAS; the β-actin gene, and quantity of hemoglobin (by the porphyrin method). It was performed blindly at Exact Sciences (Madison WI); the test for SEPT9 was performed at ARUP Laboratories (Salt Lake City UT). Results were considered positive based on the manufacturer's specificity cutoff values of 90% and 89%, respectively. Results The sDNA test detected adenomas (median 2 cm, range 1–5 cm) with 82% sensitivity (95% confidence interval [CI], 60%–95%); SEPT9 had 14% sensitivity (95% CI, 3%–35%; P=.0001). The sDNA test identified patients with CRC with 87% sensitivity (95% CI, 69%–96%); SEPT9 had 60% sensitivity (95% CI, 41%–77%; P=.046). The sDNA test identified patients with stage I–III CRC with 91% sensitivity (95% CI, 71%–99%); SEPT9 had 50% sensitivity (95% CI, 28%–72%; P=.013); for stage IV CRC, sensitivity values were 75% (95% CI, 35%–97%) and 88% (95% CI, 47%–100%), respectively (P=.56). False-positive rates were 7% for the sDNA test and 27% for SEPT9. Conclusions Based on analyses of paired samples, the sDNA test detects non-metastatic CRC and large adenomas with significantly greater levels of sensitivity than the SEPT9 test. These findings might be used to modify approaches for CRC prevention and early detection. PMID:22019796
Field-test of a date-rape drug detection device.
Quest, Dale W; Horsley, Joanne
2007-01-01
Drink Safe Technology Version 1.2 is an inexpensive color-change reagent test marketed internationally for use by consumers in settings such as a night club to detect potentially incapacitating concentrations of gamma-hydroxybutyric acid (GHB) and ketamine in beverages. The objective of this study was to compare product performance in the laboratory and performance in the hands of consumers in the field. Product performance in the laboratory adhered to the protocol defined by the manufacturer. Product performance in the hands of consumers in field settings allowed browsing participants to pipette an aliquot of their own drinks into randomly coded vials containing authentic drugs, or pure water, so as to yield the same concentrations of GHB or ketamine specified in the manufacturer-defined protocol, or blanks. Consumers were to proceed according to the directions printed on the product, and to record their results on a card with a code corresponding with the vial to which they had added an aliquot of their beverage. Diagnostic performance was calculated using two-way analysis. In the laboratory, Drink Safe Technology Version 1.2 reliably detected GHB and ketamine at concentrations specified by the manufacturer's protocol. The reactive color change denoting a positive test for GHB was rapid, but a positive test for ketamine required substantially more time to resolve. Nonetheless, test accuracy following the manufacturer's protocol in the laboratory was 100%. In the field, based on 101 paired-test results recorded by consumers, the test efficiency was 65.1%, sensitivity 50%, and specificity 91.6%. The product performed much better in the laboratory than it did in the hand of consumers in the field. There seems to be considerable potential for consumers to misinterpret a test result. The potential for consumers to record a false-negative test result for a spiked drink is cause for concern.
Radioimmunoassay test system for detection of anti-insulin antibodies
International Nuclear Information System (INIS)
Dudko, N.V.; Piven', N.V.; Ibragimova, G.V.; Kasatkin, Yu.N.
1995-01-01
A radiodiagnostic test system has been developed and commercial kit for radioimmunoassay of anti-insulin antibodies in human blood serum created. Clinical trials of the kit in patients (150 diabetics with types 1 and 2 condition) and normal subjects (n=100) demonstrated the possibility of using this kit for the detection of preclinical forms of diabetes and for distinguishing groups at risk of diabetes among children and adults, for the detection of insulin resistance, for the differential diagnosis of diabetes, and for monitoring the efficacy of insulin therapy. 9 refs.; 1 tab
Integration and road tests of a self-sensing CNT concrete pavement system for traffic detection
Han, Baoguo; Zhang, Kun; Burnham, Tom; Kwon, Eil; Yu, Xun
2013-01-01
In this paper, a self-sensing carbon nanotube (CNT) concrete pavement system for traffic detection is proposed and tested in a roadway. Pre-cast and cast-in-place self-sensing CNT concrete sensors were simultaneously integrated into a controlled pavement test section at the Minnesota Road Research Facility (MnROAD), USA. Road tests of the system were conducted by using an MnROAD five-axle semi-trailer tractor truck and a van, respectively, both in the winter and summer. Test results show that the proposed self-sensing pavement system can accurately detect the passing of different vehicles under different vehicular speeds and test environments. These findings indicate that the developed self-sensing CNT concrete pavement system can achieve real-time vehicle flow detection with a high detection rate and a low false-alarm rate.
Integration and road tests of a self-sensing CNT concrete pavement system for traffic detection
International Nuclear Information System (INIS)
Han, Baoguo; Zhang, Kun; Yu, Xun; Burnham, Tom; Kwon, Eil
2013-01-01
In this paper, a self-sensing carbon nanotube (CNT) concrete pavement system for traffic detection is proposed and tested in a roadway. Pre-cast and cast-in-place self-sensing CNT concrete sensors were simultaneously integrated into a controlled pavement test section at the Minnesota Road Research Facility (MnROAD), USA. Road tests of the system were conducted by using an MnROAD five-axle semi-trailer tractor truck and a van, respectively, both in the winter and summer. Test results show that the proposed self-sensing pavement system can accurately detect the passing of different vehicles under different vehicular speeds and test environments. These findings indicate that the developed self-sensing CNT concrete pavement system can achieve real-time vehicle flow detection with a high detection rate and a low false-alarm rate. (paper)
Viral RNA testing and automation on the bead-based CBNE detection microsystem.
Energy Technology Data Exchange (ETDEWEB)
Galambos, Paul C.; Bourdon, Christopher Jay; Farrell, Cara M.; Rossito, Paul (University of California at Davis); McClain, Jaime L.; Derzon, Mark Steven; Cullor, James Sterling (University of California at Davis); Rahimian, Kamayar
2008-09-01
We developed prototype chemistry for nucleic acid hybridization on our bead-based diagnostics platform and we established an automatable bead handling protocol capable of 50 part-per-billion (ppb) sensitivity. We are working towards a platform capable of parallel, rapid (10 minute), raw sample testing for orthogonal (in this case nucleic acid and immunoassays) identification of biological (and other) threats in a single sensor microsystem. In this LDRD we developed the nucleic acid chemistry required for nucleic acid hybridization. Our goal is to place a non-cell associated RNA virus (Bovine Viral Diarrhea, BVD) on the beads for raw sample testing. This key pre-requisite to showing orthogonality (nucleic acid measurements can be performed in parallel with immunoassay measurements). Orthogonal detection dramatically reduces false positives. We chose BVD because our collaborators (UC-Davis) can supply samples from persistently infected animals; and because proof-of-concept field testing can be performed with modification of the current technology platform at the UC Davis research station. Since BVD is a cattle-prone disease this research dovetails with earlier immunoassay work on Botulinum toxin simulant testing in raw milk samples. Demonstration of BVD RNA detection expands the repertoire of biological macromolecules that can be adapted to our bead-based detection. The resources of this late start LDRD were adequate to partially demonstrate the conjugation of the beads to the nucleic acids. It was never expected to be adequate for a full live virus test but to motivate that additional investment. In addition, we were able to reduce the LOD (Limit of Detection) for the botulinum toxin stimulant to 50 ppb from the earlier LOD of 1 ppm. A low LOD combined with orthogonal detection provides both low false negatives and low false positives. The logical follow-on steps to this LDRD research are to perform live virus identification as well as concurrent nucleic acid and
Directory of Open Access Journals (Sweden)
Mojca VIRŠČEK MARN
2015-12-01
Full Text Available Sensitivity of field tests (AgriStrip and Immunochromato, DAS-ELISA, two step RT-PCR and real-time RT-PCR for Plum pox virus (PPV detection was tested in various tissues of apricot, peach, plum and damson plum trees infected with isolates belonging to PPV-D, PPV-M or PPV-Rec, the three strains present in Slovenia. Flowers of apricot and plum in full bloom proved to be a very good source for detection of PPV. PPV could be detected with all tested techniques in symptomatic parts of leaves in May and with one exception even in the beginning of August, but it was not detected in asymptomatic leaves using field tests, DAS-ELISA and partly also molecular techniques. PPV was detected only in some of the samples of asymptomatic parts of the leaves with symptoms and of stalks by field tests and DAS-ELISA. Infections were not detected in buds in August using field tests or DAS-ELISA. Field tests are useful for confirmation of the PPV infection in symptomatic leaves, but in tissues without symptoms DAS-ELISA should be combined or replaced by molecular techniques.
Performance Test of BF3 Neutron Detection System
Energy Technology Data Exchange (ETDEWEB)
Choi, Yu Sun; Shin, Ho Cheol [KHNP-CRI, Daejeon (Korea, Republic of); Cho, Jin Bok; Oh, Sae Hyun; Ryou, Seok Jean [USERS, Daejeon (Korea, Republic of)
2015-10-15
The neutron detecting system of First-of-a-kind plant such an APR1400 at Shin Kori should have been verified in the condition of low operating temperature and pressure of the primary coolant system before receiving the operation license. Auxiliary Ex-core Neutron Flux Monitoring System (AENFMS) is supposed to be installed using BF3 neutron detector in Shin Kori plant. The performance test of AENFMS was conducted to measure neutron sensitivity, moderation ratio and count rate in the same condition with Ex-core Neutron Flux Monitoring System (ENFMS) of APR1400 to verify its detection characteristics in compliance with the functional requirement. Performance test has been conducted for AENFMS of APR1400 to verify BF3 neutron sensitivity, moderation ration of PE, expecting neutron signal count rate from AENFMS, possible extending cable length from detector to pre-amplifier. As a result of measurement, the neutron sensitivity of 34.246±0.168(95%CI)cps/nv, moderation ratio of 11.343±0.039(95%CI) and AENFMS expecting count rate related to ENFMS of 17.8 times are acceptable in compliance with functional requirement, respectively.
Optical Production and Detection of Ultrasonic Waves in Metals for Nondestructive Testing
Morrison, R. A.
1972-01-01
Ultrasonic waves were produced by striking the surface of a metal with the focused one-joule pulse of a Q-switched ruby laser. Rayleigh (surface) waves and longitudinal waves were detected with conventional transducers. Optical methods of detection were tested and developed. Rayleigh waves were produced with an oscillator and transducer. They were optically detected on curved polished surfaces, and on unpolished surfaces. The technique uses a knife edge to detect small angle changes of the surface as the wave pulse passes the illuminated spot. Optical flaw detection using pulse echo and attenuation is demonstrated.
International Nuclear Information System (INIS)
Peng, R.; Li, Y.F.; Zhang, W.J.; Hu, Q.P.
2014-01-01
This paper studies the fault detection process (FDP) and fault correction process (FCP) with the incorporation of testing effort function and imperfect debugging. In order to ensure high reliability, it is essential for software to undergo a testing phase, during which faults can be detected and corrected by debuggers. The testing resource allocation during this phase, which is usually depicted by the testing effort function, considerably influences not only the fault detection rate but also the time to correct a detected fault. In addition, testing is usually far from perfect such that new faults may be introduced. In this paper, we first show how to incorporate testing effort function and fault introduction into FDP and then develop FCP as delayed FDP with a correction effort. Various specific paired FDP and FCP models are obtained based on different assumptions of fault introduction and correction effort. An illustrative example is presented. The optimal release policy under different criteria is also discussed
KAtex antigen-detection test as a diagnostic tool for latent visceral ...
African Journals Online (AJOL)
SERVER
2008-04-03
Apr 3, 2008 ... Urine samples were tested by kAtex kit to detect VL antigen. All sera .... IFA, and ELISA-IgG and IgM) to finding of agreement and validity and reliability .... Animal inoculation is not usually employed as a diag- nostic test, since ...
Spurious Seasonality Detection: A Non-Parametric Test Proposal
Directory of Open Access Journals (Sweden)
Aurelio F. Bariviera
2018-01-01
Full Text Available This paper offers a general and comprehensive definition of the day-of-the-week effect. Using symbolic dynamics, we develop a unique test based on ordinal patterns in order to detect it. This test uncovers the fact that the so-called “day-of-the-week” effect is partly an artifact of the hidden correlation structure of the data. We present simulations based on artificial time series as well. While time series generated with long memory are prone to exhibit daily seasonality, pure white noise signals exhibit no pattern preference. Since ours is a non-parametric test, it requires no assumptions about the distribution of returns, so that it could be a practical alternative to conventional econometric tests. We also made an exhaustive application of the here-proposed technique to 83 stock indexes around the world. Finally, the paper highlights the relevance of symbolic analysis in economic time series studies.
Validation of Metagenomic Next-Generation Sequencing Tests for Universal Pathogen Detection.
Schlaberg, Robert; Chiu, Charles Y; Miller, Steve; Procop, Gary W; Weinstock, George
2017-06-01
- Metagenomic sequencing can be used for detection of any pathogens using unbiased, shotgun next-generation sequencing (NGS), without the need for sequence-specific amplification. Proof-of-concept has been demonstrated in infectious disease outbreaks of unknown causes and in patients with suspected infections but negative results for conventional tests. Metagenomic NGS tests hold great promise to improve infectious disease diagnostics, especially in immunocompromised and critically ill patients. - To discuss challenges and provide example solutions for validating metagenomic pathogen detection tests in clinical laboratories. A summary of current regulatory requirements, largely based on prior guidance for NGS testing in constitutional genetics and oncology, is provided. - Examples from 2 separate validation studies are provided for steps from assay design, and validation of wet bench and bioinformatics protocols, to quality control and assurance. - Although laboratory and data analysis workflows are still complex, metagenomic NGS tests for infectious diseases are increasingly being validated in clinical laboratories. Many parallels exist to NGS tests in other fields. Nevertheless, specimen preparation, rapidly evolving data analysis algorithms, and incomplete reference sequence databases are idiosyncratic to the field of microbiology and often overlooked.
A harmonic pulse testing method for leakage detection in deep subsurface storage formations
Sun, Alexander Y.; Lu, Jiemin; Hovorka, Susan
2015-06-01
Detection of leakage in deep geologic storage formations (e.g., carbon sequestration sites) is a challenging problem. This study investigates an easy-to-implement frequency domain leakage detection technology based on harmonic pulse testing (HPT). Unlike conventional constant-rate pressure interference tests, HPT stimulates a reservoir using periodic injection rates. The fundamental principle underlying HPT-based leakage detection is that leakage modifies a storage system's frequency response function, thus providing clues of system malfunction. During operations, routine HPTs can be conducted at multiple pulsing frequencies to obtain experimental frequency response functions, using which the possible time-lapse changes are examined. In this work, a set of analytical frequency response solutions is derived for predicting system responses with and without leaks for single-phase flow systems. Sensitivity studies show that HPT can effectively reveal the presence of leaks. A search procedure is then prescribed for locating the actual leaks using amplitude and phase information obtained from HPT, and the resulting optimization problem is solved using the genetic algorithm. For multiphase flows, the applicability of HPT-based leakage detection procedure is exemplified numerically using a carbon sequestration problem. Results show that the detection procedure is applicable if the average reservoir conditions in the testing zone stay relatively constant during the tests, which is a working assumption under many other interpretation methods for pressure interference tests. HPT is a cost-effective tool that only requires periodic modification of the nominal injection rate. Thus it can be incorporated into existing monitoring plans with little additional investment.
10 CFR 32.103 - Schedule D-prototype tests for ice detection devices containing strontium-90.
2010-01-01
... water and the strontium-90 shall be considered leakage. (e) Observations. After each of the tests... 10 Energy 1 2010-01-01 2010-01-01 false Schedule D-prototype tests for ice detection devices... § 32.103 Schedule D—prototype tests for ice detection devices containing strontium-90. An applicant for...
Prospective detection of large prediction errors: a hypothesis testing approach
International Nuclear Information System (INIS)
Ruan, Dan
2010-01-01
Real-time motion management is important in radiotherapy. In addition to effective monitoring schemes, prediction is required to compensate for system latency, so that treatment can be synchronized with tumor motion. However, it is difficult to predict tumor motion at all times, and it is critical to determine when large prediction errors may occur. Such information can be used to pause the treatment beam or adjust monitoring/prediction schemes. In this study, we propose a hypothesis testing approach for detecting instants corresponding to potentially large prediction errors in real time. We treat the future tumor location as a random variable, and obtain its empirical probability distribution with the kernel density estimation-based method. Under the null hypothesis, the model probability is assumed to be a concentrated Gaussian centered at the prediction output. Under the alternative hypothesis, the model distribution is assumed to be non-informative uniform, which reflects the situation that the future position cannot be inferred reliably. We derive the likelihood ratio test (LRT) for this hypothesis testing problem and show that with the method of moments for estimating the null hypothesis Gaussian parameters, the LRT reduces to a simple test on the empirical variance of the predictive random variable. This conforms to the intuition to expect a (potentially) large prediction error when the estimate is associated with high uncertainty, and to expect an accurate prediction when the uncertainty level is low. We tested the proposed method on patient-derived respiratory traces. The 'ground-truth' prediction error was evaluated by comparing the prediction values with retrospective observations, and the large prediction regions were subsequently delineated by thresholding the prediction errors. The receiver operating characteristic curve was used to describe the performance of the proposed hypothesis testing method. Clinical implication was represented by miss
Evaluation of point-of-care tests for detecting microalbuminuria in ...
African Journals Online (AJOL)
Evaluation of point-of-care tests for detecting microalbuminuria in diabetic patients. ... creatinine (modified Jaffe) and albumin-to-creatinine ratio (ACR). Results: Linear regression analysis demonstrated a good correlation for the HemoCue® ...
Earlier stages of colorectal cancer detected with immunochemical faecal occult blood tests
van Rossum, L. G. M.; van Rijn, A. F.; van Munster, I. P.; Jansen, J. B. M. J.; Fockens, P.; Laheij, R. J. F.; Dekker, E.
2009-01-01
Background: The aim of colorectal cancer screening is to improve prognosis by the detection of early cancer and precursor stages. We compared the stage distribution of asymptomatic colorectal cancer patients detected by a positive immunochemical or guaiac-based faecal occult blood test (FOBT) with
Improved anomaly detection using multi-scale PLS and generalized likelihood ratio test
Madakyaru, Muddu
2017-02-16
Process monitoring has a central role in the process industry to enhance productivity, efficiency, and safety, and to avoid expensive maintenance. In this paper, a statistical approach that exploit the advantages of multiscale PLS models (MSPLS) and those of a generalized likelihood ratio (GLR) test to better detect anomalies is proposed. Specifically, to consider the multivariate and multi-scale nature of process dynamics, a MSPLS algorithm combining PLS and wavelet analysis is used as modeling framework. Then, GLR hypothesis testing is applied using the uncorrelated residuals obtained from MSPLS model to improve the anomaly detection abilities of these latent variable based fault detection methods even further. Applications to a simulated distillation column data are used to evaluate the proposed MSPLS-GLR algorithm.
Improved anomaly detection using multi-scale PLS and generalized likelihood ratio test
Madakyaru, Muddu; Harrou, Fouzi; Sun, Ying
2017-01-01
Process monitoring has a central role in the process industry to enhance productivity, efficiency, and safety, and to avoid expensive maintenance. In this paper, a statistical approach that exploit the advantages of multiscale PLS models (MSPLS) and those of a generalized likelihood ratio (GLR) test to better detect anomalies is proposed. Specifically, to consider the multivariate and multi-scale nature of process dynamics, a MSPLS algorithm combining PLS and wavelet analysis is used as modeling framework. Then, GLR hypothesis testing is applied using the uncorrelated residuals obtained from MSPLS model to improve the anomaly detection abilities of these latent variable based fault detection methods even further. Applications to a simulated distillation column data are used to evaluate the proposed MSPLS-GLR algorithm.
Radon detection system, design, test and performance
International Nuclear Information System (INIS)
Balcazar, M.; Chavez, A.; Pina-Villalpando, G.; Navarrete, M.
1999-01-01
A portable radon detection system (α-Inin) has been designed and constructed for using it in adverse environmental conditions where humidity, temperature and chemical vaporous are present. The minimum integration time is in periods of 15 min during 41 days. A 12 V battery and a photovoltaic module allow the α-Inin autonomy in field measurements. Data is collected by means of a laptop computer where data processing and α-Inin programming are carried out. α-Inin performance was simultaneously tested in a controlled radon chamber, together with a commercial α-Meter
[The advance of detection technology of HIV self-testing].
Yan, L; Xiao, P P; Yan, H J; Huan, X P; Fu, G F; Li, J J; Yang, H T
2017-11-06
At present, China's AIDS testing increased rapidly, but there are still many people living with HIV do not recognize their status, thus postponing the antiviral treatment time. HIV self-testing (HST) is an effective method to expand the testing, not only simple operation, easy to get a result, effectively protect the detection privacy, expand the selection of testers, suit to the entire population, but also the premise and basis of other AIDS comprehensive prevention measures, all over the world are promoting it. Because the HST has controversies in the window period, price and before and after controversial, and our country is in the initial stage of HST, so it is not to develop related policies, but more and more countries are in accordance with their own situations are modified or developed to allow to use rapid detection of AIDS policy to regulate the field. This paper analyzed and summarized the advantage and influence factors of HST promotion, HST believes that in the long term, the advantages outweigh the disadvantages, we need to formulate relevant policies, and improve the sensitivity of the kit, shorten the window period of time, production and promotion of operation standard of video, specification and testing the operating practices, preventing and reporting the possible social harm, investigation and understanding of the needs of the people of the crowd, to maximize the advantages of HST, find more infection, so as to curb the epidemic of AIDS.
Bernabeu, Sandrine; Dortet, Laurent; Naas, Thierry
2017-06-01
There is an urgent need for accurate and fast diagnostic tests to identify carbapenemase-producing bacteria. Here, we have evaluated a novel colorimetric test (the β-CARBA™ test; Bio-Rad) to detect carbapenemase-producing Gram-negative bacilli from cultured colonies. The performance of the β-CARBA™ test was compared with that of the Carba NP test (or the CarbAcineto NP test) and RAPIDEC ® CARBA NP (bioMérieux) using a collection of 290 isolates with characterized β-lactamase content. This collection included 199 carbapenemase producers (121 Enterobacteriaceae, 36 Pseudomonas and 42 Acinetobacter baumannii ) and 91 non-carbapenemase producers (55 Enterobacteriaceae, 20 Pseudomonas and 16 A. baumannii ). The β-CARBA™ test correctly detected 84.9% of the carbapenemase producers, including all KPC and IMP, 96.4% of VIM, 85.3% of NDM, 80.5% of OXA-48-like and 91.2% of A. baumannii -related OXA carbapenemases (OXA-23, OXA-40, OXA-58, OXA-143 and overexpressed OXA-51). All rare metallo-β-lactamases (SPM, AIM, GIM, DIM and SIM) were detected. Importantly, all non-KPC Ambler class A carbapenemases were not detected, including GES variants with carbapenemase activity ( n = 6), IMI ( n = 3), NMC-A ( n = 1), SME ( n = 2), FRI-1 ( n = 1) and BIC-1 ( n = 1). All non-carbapenemase producers gave a negative result except with OXA-163-, OXA-405- and one TEM-3-producing Citrobacter freundii . The overall sensitivity and specificity of the β-CARBA™ test were 84.9% and 95.6%, respectively. This test is easy to perform and to interpret by non-specialized staff members. Despite lack of specificity towards non-KPC Ambler class A and OXA-48-like carbapenemases, the β-CARBA™ test could complete the existing panel of tests available for the confirmation of carbapenemases in Gram-negatives. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For
Human anti-HIV IgM detection by the OraQuick ADVANCE® Rapid HIV 1/2 Antibody Test.
Guillon, Geraldine; Yearwood, Graham; Snipes, Casey; Boschi, Daniel; Reed, Michael R
2018-01-01
The Centers for Disease Control and Prevention (CDC) and many public health jurisdictions continue to advocate for the most sensitive rapid HIV test that is available. Currently, the recommendation is to utilize tests that can detect HIV infection biomarkers within 30 days of infection, when initial immune responses are mounted. The infected patient's IgM response is often used to detect acute infection within a 20-25 days window after infection. This requirement applies to lab-based testing with automated analyzers and rapid, point of care (POC) testing used for screening in a non-clinical setting. A recent study has demonstrated that POC tests using a Protein A-based detection system can detect samples with predominantly HIV-1 IgM reactivity (Moshgabadi et al., 2015). The OraQuick ADVANCE ® Rapid HIV-1/2 Antibody Test (OraQuick ADVANCE ®) also uses Protein A as the detection protein in the antibody-binding colloidal gold conjugate, so it is expected that the OraQuick ADVANCE ® Test will also detect samples with predominantly IgM reactivity. This report definitively demonstrates that the OraQuick ADVANCE ® Test can detect IgM antibodies during an acute infection window period of approximately 20-25 days after infection, and is therefore suitable for use in testing environments requiring adherence to current CDC recommendations.
Waggoner, Jesse J; Balassiano, Ilana; Mohamed-Hadley, Alisha; Vital-Brazil, Juliana Magalhães; Sahoo, Malaya K; Pinsky, Benjamin A
2015-01-01
Reference diagnostic tests for leptospirosis include nucleic acid amplification tests, bacterial culture, and microscopic agglutination testing (MAT) of acute and convalescent serum. However, clinical laboratories often do not receive paired specimens. In the current study, we tested serum samples using a highly sensitive real-time nucleic acid amplification test for Leptospira and compared results to MAT performed on the same specimens. 478 serum samples from suspected leptospirosis cases in Rio de Janeiro were tested using a real-time RT-PCR for the diagnosis of leptospirosis, malaria and dengue (the Lepto-MD assay). The Lepto-MD assay detects all species of Leptospira (saprophytic, intermediate, and pathogenic), and in the current study, we demonstrate that this assay amplifies both Leptospira RNA and DNA. Dengue virus RNA was identified in 10 patients, and no cases of malaria were detected. A total of 65 samples (13.6%) were positive for Leptospira: 35 samples (7.3%) in the Lepto-MD assay, 33 samples (6.9%) by MAT, and 3 samples tested positive by both (kappa statistic 0.02). Poor agreement between methods was consistent regardless of the titer used to define positive MAT results or the day of disease at sample collection. Leptospira nucleic acids were detected in the Lepto-MD assay as late as day 22, and cycle threshold values did not differ based on the day of disease. When Lepto-MD assay results were added to the MAT results for all patients in 2008 (n=818), the number of detected leptospirosis cases increased by 30.4%, from 102 (12.5%) to 133 (16.3%). This study demonstrates a lack of agreement between nucleic acid detection of Leptospira and single-specimen MAT, which may result from the clearance of bacteremia coinciding with the appearance of agglutinating antibodies. A combined testing strategy for acute leptospirosis, including molecular and serologic testing, appears necessary to maximize case detection.
Using electrolyte leakage tests to determine lifting windows and detect tissue damage
Richard W. Tinus
2002-01-01
Physiological testing is rapidly coming into use as a means to determine the condition of nursery stock and predict how it will respond to treatment or use. One such test, the electrolyte leakage test, can be used to measure cold hardiness and detect tissue damage. The principle of this test is that when cell membranes are damaged, electrolytes leak out into the water...
Fault detection by surface seismic scanning tunneling macroscope: Field test
Hanafy, Sherif M.
2014-08-05
The seismic scanning tunneling macroscope (SSTM) is proposed for detecting the presence of near-surface impedance anomalies and faults. Results with synthetic data are consistent with theory in that scatterers closer to the surface provide brighter SSTM profiles than those that are deeper. The SSTM profiles show superresolution detection if the scatterers are in the near-field region of the recording line. The field data tests near Gulf of Aqaba, Haql, KSA clearly show the presence of the observable fault scarp, and identify the subsurface presence of the hidden faults indicated in the tomograms. Superresolution detection of the fault is achieved, even when the 35 Hz data are lowpass filtered to the 5-10 Hz band.
Fault detection by surface seismic scanning tunneling macroscope: Field test
Hanafy, Sherif M.; Schuster, Gerard T.
2014-01-01
The seismic scanning tunneling macroscope (SSTM) is proposed for detecting the presence of near-surface impedance anomalies and faults. Results with synthetic data are consistent with theory in that scatterers closer to the surface provide brighter SSTM profiles than those that are deeper. The SSTM profiles show superresolution detection if the scatterers are in the near-field region of the recording line. The field data tests near Gulf of Aqaba, Haql, KSA clearly show the presence of the observable fault scarp, and identify the subsurface presence of the hidden faults indicated in the tomograms. Superresolution detection of the fault is achieved, even when the 35 Hz data are lowpass filtered to the 5-10 Hz band.
14C-urea breath test for the detection of Helicobacter pylori
Veldhuyzen van Zanten, S. J.; Tytgat, K. M.; Hollingsworth, J.; Jalali, S.; Rshid, F. A.; Bowen, B. M.; Goldie, J.; Goodacre, R. L.; Riddell, R. H.; Hunt, R. H.
1990-01-01
The high urease activity of Helicobacter pylori can be used to detect this bacterium by noninvasive breath tests. We have developed a 14C-urea breath test which uses 5 microCi 14C with 50 mg nonradioactive urea. Breath samples are collected at baseline and every 30 min for 2 h. Our study compared
Germination test as a fast method to detect glyphosate-resistant sourgrass
Directory of Open Access Journals (Sweden)
Marcos Altomani Neves Dias
2015-01-01
Full Text Available The occurrence of weed species with different levels of resistance to glyphosate has increasingly spread in agricultural areas. In Brazil, sourgrass is among the main species presenting issues in this regard. Thus, fast and reliable methods to detect glyphosate resistance are of special interest for this specie, either for research or rational management purposes. This study was carried out to verify the feasibility of using the germination test to detect glyphosate resistance in sourgrass. The experiment was conducted with two sourgrass biotypes, with different levels of susceptibility to glyphosate. The seeds were previously imbibed in solutions composed of 0, 0.1875%, 0.25%, 0.75%, 1.5%, 3% and 6% of glyphosate during two periods, five and ten minutes, and submitted to germination tests. The results indicate the germination test as a feasible and time-saving approach to evaluate glyphosate-resistant sourgrass, with results available in seven days.
Germination test as a fast method to detect glyphosate-resistant sourgrass
Directory of Open Access Journals (Sweden)
Marcos Altomani Neves Dias
2015-09-01
Full Text Available The occurrence of weed species with different levels of resistance to glyphosate has increasingly spread in agricultural areas. In Brazil, sourgrass is among the main species presenting issues in this regard. Thus, fast and reliable methods to detect glyphosate resistance are of special interest for this specie, either for research or rational management purposes. This study was carried out to verify the feasibility of using the germination test to detect glyphosate resistance in sourgrass. The experiment was conducted with two sourgrass biotypes, with different levels of susceptibility to glyphosate. The seeds were previously imbibed in solutions composed of 0, 0.1875%, 0.25%, 0.75%, 1.5%, 3% and 6% of glyphosate during two periods, five and ten minutes, and submitted to germination tests. The results indicate the germination test as a feasible and time-saving approach to evaluate glyphosate-resistant sourgrass, with results available in seven days.
Ivan, M.G.; Vivet, F.; Meinders, E.R.
2010-01-01
Flexible microfluidic devices made of poly(dimethylsiloxane) (PDMS) were manufactured by soft lithography, and tested in detection of ionic species using optical absorption spectroscopy and electrical measurements. PDMS was chosen due to its flexibility and ease of surface modification by exposure to plasma and UV treatment, its transparency in UV-Vis regions of the light spectrum, and biocompatibility. The dual-detection mechanism allows the user more freedom in choosing the detection tool, ...
Rapid Detection of the Chlamydiaceae and Other Families in the Order Chlamydiales: Three PCR Tests
Everett, Karin D. E.; Hornung, Linda J.; Andersen, Arthur A.
1999-01-01
Few identification methods will rapidly or specifically detect all bacteria in the order Chlamydiales, family Chlamydiaceae. In this study, three PCR tests based on sequence data from over 48 chlamydial strains were developed for identification of these bacteria. Two tests exclusively recognized the Chlamydiaceae: a multiplex test targeting the ompA gene and the rRNA intergenic spacer and a TaqMan test targeting the 23S ribosomal DNA. The multiplex test was able to detect as few as 200 inclusion-forming units (IFU), while the TaqMan test could detect 2 IFU. The amplicons produced in these tests ranged from 132 to 320 bp in length. The third test, targeting the 23S rRNA gene, produced a 600-bp amplicon from strains belonging to several families in the order Chlamydiales. Direct sequence analysis of this amplicon has facilitated the identification of new chlamydial strains. These three tests permit ready identification of chlamydiae for diagnostic and epidemiologic study. The specificity of these tests indicates that they might also be used to identify chlamydiae without culture or isolation. PMID:9986815
Field Tests of a Tractor Rollover Detection and Emergency Notification System.
Liu, B; Koc, A B
2015-04-01
The objective of this research was to assess the feasibility of a rollover detection and emergency notification system for farm tractors using field tests. The emergency notification system was developed based on a tractor stability model and implemented on a mobile electronic device with the iOS operating system. A complementary filter was implemented to combine the data from the accelerometer and gyroscope sensors to improve their accuracies in calculating the roll and pitch angles and the roll and pitch rates. The system estimates a stability index value during tractor operation, displays feedback messages when the stability index is lower than a preset threshold value, and transmits emergency notification messages when an overturn happens. Ten tractor rollover tests were conducted on a field track. The developed system successfully monitored the stability of the tractor during all of the tests. The iOS application was able to detect rollover accidents and transmit emergency notifications in the form of a phone call and email when an accident was detected. The system can be a useful tool for training and education in safe tractor operation. The system also has potential for stability monitoring and emergency notification of other on-road and off-road motorized vehicles.
Ivan, Marius G.; Vivet, Frédéric; Meinders, Erwin R.
2010-06-01
Flexible microfluidic devices made of poly(dimethylsiloxane) (PDMS) were manufactured by soft lithography, and tested in detection of ionic species using optical absorption spectroscopy and electrical measurements. PDMS was chosen due to its flexibility and ease of surface modification by exposure to plasma and UV treatment, its transparency in UV-Vis regions of the light spectrum, and biocompatibility. The dual-detection mechanism allows the user more freedom in choosing the detection tool, and a functional device was successfully tested. Optical lithography was employed for manufacturing templates, which were subsequently used for imprinting liquid PDMS by thermal curing. Gold electrodes having various widths and distances among them were patterned with optical lithography on the top part which sealed the microchannels, and the devices were employed for detection of ionic species in aqueous salt solutions as well as micro-electrolysis cells. Due to the transparency of PDMS in UV-Vis the microfluidics were also used as photoreactors, and the in-situ formed charged species were monitored by applying a voltage between electrodes. Upon addition of a colorimetric pH sensor, acid was detected with absorption spectroscopy.
Eddy Current Testing for Detecting Small Defects in Thin Films
Obeid, Simon; Tranjan, Farid M.; Dogaru, Teodor
2007-03-01
Presented here is a technique of using Eddy Current based Giant Magneto-Resistance sensor (GMR) to detect surface and sub-layered minute defects in thin films. For surface crack detection, a measurement was performed on a copper metallization of 5-10 microns thick. It was done by scanning the GMR sensor on the surface of the wafer that had two scratches of 0.2 mm, and 2.5 mm in length respectively. In another experiment, metal coatings were deposited over the layers containing five defects with known lengths such that the defects were invisible from the surface. The limit of detection (resolution), in terms of defect size, of the GMR high-resolution Eddy Current probe was studied using this sample. Applications of Eddy Current testing include detecting defects in thin film metallic layers, and quality control of metallization layers on silicon wafers for integrated circuits manufacturing.
A fluorescence quenching test for the detection of flavonoid transformation.
Schoefer, L; Braune, A; Blaut, M
2001-11-13
A novel fluorescence quenching test for the detection of flavonoid degradation by microorganisms was developed. The test is based on the ability of the flavonoids to quench the fluorescence of 1,6-diphenyl-1,3,5-hexatriene (DPH). Several members of the anthocyanidins, flavones, isoflavones, flavonols, flavanones, dihydroflavanones, chalcones, dihydrochalcones and catechins were tested with regard to their quenching properties. The anthocyanidins were the most potent quenchers of DPH fluorescence, while the flavanones, dihydroflavanones and dihydrochalcones, quenched the fluorescence only weakly. The catechins had no visible impact on DPH fluorescence. The developed test allows a quick and easy differentiation between flavonoid-degrading and flavonoid-non-degrading bacteria. The investigation of individual reactions of flavonoid transformation with the developed test system is also possible.
Detection of antibiotic residues in food by Charm II test
International Nuclear Information System (INIS)
Addali, Mohamed
2014-01-01
Antibiotics are used in food to: -therapy and prophylaxis, -increase the productivity of the food producing animals. The presence of antimicrobial residues: -constitutes a potential human health hazard. has significant impact on international food trade. has implications on technological process in dairy industry. Detection of antibiotic residues is of great interest. It helps protect humans against the effects of such residues, the more it can support the participation of our country in international trade. Charm II test is one of the methods of detection of antimicrobial residues. The tests utilize microbial or antibody receptor assay technology. The sample is incubated with a binding agent (microbial cells with specific receptor sites or with specific antibodies attached) and a tracer (the radio-labeled version of the antibiotic to be detected). The amount of tracer on the binding agent is measured using a scintillation counter and is compared to a pre-determined cut-off or control point. If contaminating antibiotic is present, it will prevent the binding of the tracer by occupying the receptors on the binding agent. The less labeled tracer detected, the more contaminating antibiotic there is present in the sample. This work, carried out at the Radiochemical Laboratory of the National Centre of Nuclear Science and Technology, has two parts: 1/ The first is reserved to a literature review provides an overview on antibiotics and the charm II method. 2/ The second is devoted to the experimental study and presentation of results.
Detection of gonococcal infection : pros and cons of a rapid test.
Vickerman, Peter; Peeling, Rosanna W; Watts, Charlotte; Mabey, David
2005-01-01
WHO estimates that 62 million cases of gonorrhea occur annually worldwide. Untreated infection can cause serious long-term complications, especially in women. In addition, Neisseria gonorrheae infection can facilitate HIV transmission, and babies born to infected mothers are at risk of ocular infection, which can lead to blindness. Where diagnostic facilities are lacking, gonorrhea can be treated syndromically. However, this inevitably leads to over-treatment, especially in women in whom the syndrome of vaginal discharge may be due not to N. gonorrheae infection but to several other more prevalent conditions. Over-treatment is a major concern because of widespread N. gonorrheae antibiotic resistance. Moreover, a high proportion of gonorrhea cases are asymptomatic and so do not present for syndromic management. Such cases will only be detected by screening tests. The gold standard test for the detection of N. gonorrheae is culture, which has high sensitivity and specificity. However, it requires well trained staff and its performance is affected by specimen transport conditions. Other options include microscopy and tests that detect gonococcal antigen or nucleic acid. Nucleic acid amplification tests (NAATs) have higher sensitivity and can be used on non-invasive samples (urine). However, they can cross-react with other Neisseria species and are expensive, requiring highly trained staff and sophisticated equipment. In settings where patients are asked to return for laboratory results, some infected patients never receive treatment as they fail to return for their test results. This reduction in treatment, and the possible onward transmission of N. gonorrheae during any delay in treatment, means that a rapid test of lower sensitivity may be more effective if it results in patients being treated at the initial visit. Indeed, even with the low sensitivity of currently available rapid tests (50-70%), modeling shows that they can outperform gold standard tests in
Cluster Detection Tests in Spatial Epidemiology: A Global Indicator for Performance Assessment.
Directory of Open Access Journals (Sweden)
Aline Guttmann
Full Text Available 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.
Cluster Detection Tests in Spatial Epidemiology: A Global Indicator for Performance Assessment
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
CONFU: Configuration Fuzzing Testing Framework for Software Vulnerability Detection.
Dai, Huning; Murphy, Christian; Kaiser, Gail
2010-01-01
Many software security vulnerabilities only reveal themselves under certain conditions, i.e., particular configurations and inputs together with a certain runtime environment. One approach to detecting these vulnerabilities is fuzz testing. However, typical fuzz testing makes no guarantees regarding the syntactic and semantic validity of the input, or of how much of the input space will be explored. To address these problems, we present a new testing methodology called Configuration Fuzzing. Configuration Fuzzing is a technique whereby the configuration of the running application is mutated at certain execution points, in order to check for vulnerabilities that only arise in certain conditions. As the application runs in the deployment environment, this testing technique continuously fuzzes the configuration and checks "security invariants" that, if violated, indicate a vulnerability. We discuss the approach and introduce a prototype framework called ConFu (CONfiguration FUzzing testing framework) for implementation. We also present the results of case studies that demonstrate the approach's feasibility and evaluate its performance.
Detectability Measurement of GPR for Buried Target in Self-Designed Test Field
International Nuclear Information System (INIS)
Son, Soo Jung; Shin, Byoung Chul
2000-01-01
In this paper, we were investigated the detectability on various specimen in self-designed test field using the GPR system with three antenna elements. The GPR system was constantly radiated 730MHz frequency. To examine the detectability on various condition, the test were experimented using different materials, size and buried depth. As an adjusted wave-propagation velocity, the location of hyperbolic curve pattern were displayed B-scan CRT. And the pattern was exactly positioned when it was compared to the real buried-depth. Therefore, we can confirm similarity between the wave-propagation velocity and previous results
Imaging evaluation of infants with neuroblastoma detected by VMA screening spot test
International Nuclear Information System (INIS)
Fujioka, M.; Saiki, N.; Aihara, T.; Yamamoto, K.
1988-01-01
In the Saitama Prefecture in Japan, VMA (vanillyl manderic acid) screening spot test for detection of neuroblastoma has been performed in 173,046 infants in the years 1981-1986 and 15 infants were found to have neuroblastoma. Two infants had mediastinal tumors and the remainder, 13, had intraabdominal tumors. Only 7 infants had palpable masses. Although CT was documented to be the best imaging procedure to provide sufficient information for treatment, conventional radiographic examinations of the chest and abdomen, and abdominal ultrasonography were able, as initial imaging procedures, to detect reasonably small neuroblastomas in infants with a positive VMA screening test. (orig.)
Real time testing of intelligent relays for synchronous distributed generation islanding detection
Zhuang, Davy
As electric power systems continue to grow to meet ever-increasing energy demand, their security, reliability, and sustainability requirements also become more stringent. The deployment of distributed energy resources (DER), including generation and storage, in conventional passive distribution feeders, gives rise to integration problems involving protection and unintentional islanding. Distributed generators need to be islanded for safety reasons when disconnected or isolated from the main feeder as distributed generator islanding may create hazards to utility and third-party personnel, and possibly damage the distribution system infrastructure, including the distributed generators. This thesis compares several key performance indicators of a newly developed intelligent islanding detection relay, against islanding detection devices currently used by the industry. The intelligent relay employs multivariable analysis and data mining methods to arrive at decision trees that contain both the protection handles and the settings. A test methodology is developed to assess the performance of these intelligent relays on a real time simulation environment using a generic model based on a real-life distribution feeder. The methodology demonstrates the applicability and potential advantages of the intelligent relay, by running a large number of tests, reflecting a multitude of system operating conditions. The testing indicates that the intelligent relay often outperforms frequency, voltage and rate of change of frequency relays currently used for islanding detection, while respecting the islanding detection time constraints imposed by standing distributed generator interconnection guidelines.
Stokes, A F; Banich, M T; Elledge, V C
1991-08-01
The FAA has expressed concern that flight safety could be compromised by undetected cognitive impairment in pilots due to conditions such as substance abuse, mental illness, and neuropsychological problems. Interest has been shown in the possibility of adding a brief "mini-mental exam," or a simple automated test-battery to the standard flight medical to screen for such conditions. The research reported here involved the empirical evaluation of two "mini-mental exams," two paper-and-pencil test batteries, and a prototype version of an automated screening battery. Sensitivity, specificity, and positive predictive value were calculated for each sub-task in a discriminant study of 54 pilots and 62 individuals from a heterogeneous clinical population. Results suggest that the "mini-mental exams" are poor candidates for a screening test. The automated battery showed the best discrimination performance, in part because of the incorporation of dual-task tests of divided attention performance. These tests appear to be particularly sensitive to otherwise difficult-to-detect cognitive impairments of a mild or subtle nature. The use of an automated battery of tests as a screening instrument does appear to be feasible in principle, but the practical success of a screening program is heavily dependent upon the actual prevalence of cognitive impairment in the medical applicant population.
Sampson, Maureen L; Gounden, Verena; van Deventer, Hendrik E; Remaley, Alan T
2016-02-01
The main drawback of the periodic analysis of quality control (QC) material is that test performance is not monitored in time periods between QC analyses, potentially leading to the reporting of faulty test results. The objective of this study was to develop a patient based QC procedure for the more timely detection of test errors. Results from a Chem-14 panel measured on the Beckman LX20 analyzer were used to develop the model. Each test result was predicted from the other 13 members of the panel by multiple regression, which resulted in correlation coefficients between the predicted and measured result of >0.7 for 8 of the 14 tests. A logistic regression model, which utilized the measured test result, the predicted test result, the day of the week and time of day, was then developed for predicting test errors. The output of the logistic regression was tallied by a daily CUSUM approach and used to predict test errors, with a fixed specificity of 90%. The mean average run length (ARL) before error detection by CUSUM-Logistic Regression (CSLR) was 20 with a mean sensitivity of 97%, which was considerably shorter than the mean ARL of 53 (sensitivity 87.5%) for a simple prediction model that only used the measured result for error detection. A CUSUM-Logistic Regression analysis of patient laboratory data can be an effective approach for the rapid and sensitive detection of clinical laboratory errors. Published by Elsevier Inc.
Evaluation of a New and Rapid Serologic Test for Detecting Brucellosis: Brucella Coombs Gel Test.
Hanci, Hayrunisa; Igan, Hakan; Uyanik, Muhammet Hamidullah
2017-01-01
Many serological tests have been used for the diagnosis of human brucellosis. A new serological method is identified as Brucella Coombs gel test based on the principle of centrifugation gel system similar to the gel system used in blood group determination. In this system, if Brucella antibodies were present in the serum, antigen and antibody would remain as a pink complex on the gel. Otherwise, the pink Brucella antigens would precipitate at the bottom of the gel card system. In this study, we aimed to compare the Brucella Coombs gel test, a new, rapid screen and titration method for detection of non-agglutinating IgG with the Brucella Coombs test. For this study, a total of 88 serum samples were obtained from 45 healthy persons and 43 individuals who had clinical signs and symptoms of brucellosis. For each specimen, Rose Bengal test, standard agglutination test, Coombs test and Brucella Coombs gel test were carried out. Sensitivity and specificity of Brucella Coombs gel test were found as 100.0 and 82.2%, respectively. Brucella Coombs gel test can be used as a screening test with high sensitivity. By the help of pink Brucella antigen precipitation, the tests' evaluation is simple and objective. In addition, determination of Brucella antibody by rapid titration offers another important advantage.
Olodaterol and vilanterol detection in sport drug testing.
Chundela, Zdenek; Große, Joachim
2015-01-01
The possibility of the detection of olodaterol and vilanterol, two novel β2 -agonists, in human urine for the purpose of sport drug testing was investigated. Compounds of interest were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) employing methods commonly used in the World Anti-Doping Agency (WADA) accredited laboratories. For both substances, the respective parent compound was found to be a suitable target analyte for monitoring therapeutic dose administration. Copyright © 2015 John Wiley & Sons, Ltd.
Directory of Open Access Journals (Sweden)
Russell I Heigh
Full Text Available Precursors to 1/3 of colorectal cancer (CRC, serrated polyps have been under-detected by screening due to their inconspicuous, non-hemorrhagic, and proximal nature. A new multi-target stool DNA test (multi-target sDNA shows high sensitivity for both CRC and advanced adenomas. Screen detection of serrated polyps by this approach requires further validation. We sought to assess and compare noninvasive detection of sessile serrated polyps (SSP ≥ 1 cm by sDNA and an occult blood fecal immunochemical test (FIT.In a blinded prospective study, a single stool sample used for both tests was collected from 456 asymptomatic adults prior to screening or surveillance colonoscopy (criterion standard. All 29 patients with SSP ≥ 1 cm were included as cases and all 232 with no neoplastic findings as controls. Buffered stool samples were processed and frozen on receipt; Exact Sciences performed sDNA in batches using optimized analytical methods. The sDNA multi-marker panel targets methylated BMP3 (mBMP3 and NDRG4, mutant KRAS, β-actin, and hemoglobin. FIT (Polymedco OC-FIT Check was performed in separate lab ≤ 2 days post defecation and evaluated at cutoffs of 50 (FIT-50 and 100 ng/ml (FIT-100.MEDIAN AGES: cases 61 (range 57-77, controls 62 (52-70, p = NS. Women comprised 59% and 51%, p = NS, respectively. SSP median size was 1.2 cm (1-3 cm, 93% were proximal, and 64% had synchronous diminutive polyps. Among multi-target sDNA markers, mBMP3 proved highly discriminant for detection of SSP ≥ 1 cm (AUC = 0.87, p<0.00001; other DNA markers provided no incremental sensitivity. Hemoglobin alone showed no discrimination (AUC = 0.50, p = NS. At matched specificities, detection of SSP ≥ 1 cm by stool mBMP3 was significantly greater than by FIT-50 (66% vs 10%, p = 0.0003 or FIT-100 (63% vs 0%, p<0.0001.In a screening and surveillance setting, SSP ≥ 1 cm can be detected noninvasively by stool assay of exfoliated DNA markers, especially mBMP3. FIT appears to
[Micron]ADS-B Detect and Avoid Flight Tests on Phantom 4 Unmanned Aircraft System
Arteaga, Ricardo; Dandachy, Mike; Truong, Hong; Aruljothi, Arun; Vedantam, Mihir; Epperson, Kraettli; McCartney, Reed
2018-01-01
Researchers at the National Aeronautics and Space Administration Armstrong Flight Research Center in Edwards, California and Vigilant Aerospace Systems collaborated for the flight-test demonstration of an Automatic Dependent Surveillance-Broadcast based collision avoidance technology on a small unmanned aircraft system equipped with the uAvionix Automatic Dependent Surveillance-Broadcast transponder. The purpose of the testing was to demonstrate that National Aeronautics and Space Administration / Vigilant software and algorithms, commercialized as the FlightHorizon UAS"TM", are compatible with uAvionix hardware systems and the DJI Phantom 4 small unmanned aircraft system. The testing and demonstrations were necessary for both parties to further develop and certify the technology in three key areas: flights beyond visual line of sight, collision avoidance, and autonomous operations. The National Aeronautics and Space Administration and Vigilant Aerospace Systems have developed and successfully flight-tested an Automatic Dependent Surveillance-Broadcast Detect and Avoid system on the Phantom 4 small unmanned aircraft system. The Automatic Dependent Surveillance-Broadcast Detect and Avoid system architecture is especially suited for small unmanned aircraft systems because it integrates: 1) miniaturized Automatic Dependent Surveillance-Broadcast hardware; 2) radio data-link communications; 3) software algorithms for real-time Automatic Dependent Surveillance-Broadcast data integration, conflict detection, and alerting; and 4) a synthetic vision display using a fully-integrated National Aeronautics and Space Administration geobrowser for three dimensional graphical representations for ownship and air traffic situational awareness. The flight-test objectives were to evaluate the performance of Automatic Dependent Surveillance-Broadcast Detect and Avoid collision avoidance technology as installed on two small unmanned aircraft systems. In December 2016, four flight tests
Analysis of brief language tests in the detection of cognitive decline and dementia
Directory of Open Access Journals (Sweden)
Marcia Radanovic
Full Text Available Abstract Lexical access difficulties are frequent in normal aging and initial stages of dementia. Verbal fluency tests are valuable to detect cognitive decline, evidencing lexico-semantic and executive dysfunction. Objectives: To establish which language tests can contribute in detecting dementia and to verify schooling influence on subject performance. Method: 74 subjects: 33 controls, 17 Clinical Dementia Rating (CDR 0.5 and 24 (Brief Cognitive Battery - BCB e Boston Naming Test - BNT 1 were compared in tests of semantic verbal fluency (animal and fruit, picture naming (BCB and BNT and the language items of Mini Mental State Examination (MMSE. Results: There were significant differences between the control group and both CDR 0.5 and CDR 1 in all tests. Cut-off scores were: 11 and 10 for animal fluency, 8 for fruit fluency (in both, 8 and 9 for BCB naming. The CDR 0.5 group performed better than the CDR 1 group only in animal fluency. Stepwise multiple regression revealed fruit fluency, animal fluency and BCB naming as the best discriminators between patients and controls (specificity: 93.8%; sensitivity: 91.3%. In controls, comparison between illiterates and literates evidenced schooling influence in all tests, except for fruit fluency and BCB naming. In patients with dementia, only fruit fluency was uninfluenced by schooling. Conclusion: The combination of verbal fluency tests in two semantic categories along with a simple picture naming test is highly sensitive in detecting cognitive decline. Comparison between literate and illiterate subjects shows a lesser degree of influence of schooling on the selected tests, thus improving discrimination between low performance and incipient cognitive decline.
Comparison and transfer testing of multiplex ligation detection methods for GM plants
Directory of Open Access Journals (Sweden)
Ujhelyi Gabriella
2012-01-01
Full Text Available Abstract Background With the increasing number of GMOs on the global market the maintenance of European GMO regulations is becoming more complex. For the analysis of a single food or feed sample it is necessary to assess the sample for the presence of many GMO-targets simultaneously at a sensitive level. Several methods have been published regarding DNA-based multidetection. Multiplex ligation detection methods have been described that use the same basic approach: i hybridisation and ligation of specific probes, ii amplification of the ligated probes and iii detection and identification of the amplified products. Despite they all have this same basis, the published ligation methods differ radically. The present study investigated with real-time PCR whether these different ligation methods have any influence on the performance of the probes. Sensitivity and the specificity of the padlock probes (PLPs with the ligation protocol with the best performance were also tested and the selected method was initially validated in a laboratory exchange study. Results Of the ligation protocols tested in this study, the best results were obtained with the PPLMD I and PPLMD II protocols and no consistent differences between these two protocols were observed. Both protocols are based on padlock probe ligation combined with microarray detection. Twenty PLPs were tested for specificity and the best probes were subjected to further evaluation. Up to 13 targets were detected specifically and simultaneously. During the interlaboratory exchange study similar results were achieved by the two participating institutes (NIB, Slovenia, and RIKILT, the Netherlands. Conclusions From the comparison of ligation protocols it can be concluded that two protocols perform equally well on the basis of the selected set of PLPs. Using the most ideal parameters the multiplicity of one of the methods was tested and 13 targets were successfully and specifically detected. In the
An ELISA test for the detection of antibodies to Legionella pneumophila.
Wreghitt, T G; Nagington, J; Gray, J
1982-01-01
An enzyme-linked immunosorbent assay (ELISA) test has been developed to detect antibodies to Legionella pneumophila serogroup 1. There is good correlation between indirect fluorescent antibody (IFA) and ELISA titres but ELISA is more sensitive.
The sensitivity of tests to detect in vivo platelet activation induced by ...
African Journals Online (AJOL)
No influence on the results of the platelet function tests was found. Tile only test capable of detecting limited injury to the endothelium was the measurement of plasma PF4: The mean platelet life-span (MPLS) shortened, mean platelet density decreased, the circulating platelet aggregate ratio decreased, and plasma levels ...
W.B. van Leeuwen (Willem); C. van Pelt (Cindy); A. Luijendijk (Ad); H.A. Verbrugh (Henri); W.H.F. Goessens (Wil)
1999-01-01
textabstractThe slide agglutination test MRSA-Screen (Denka Seiken Co., Niigata, Japan) was compared with the mecA PCR ("gold standard") for the detection of methicillin resistance in Staphylococcus aureus. The MRSA-Screen test detected the penicillin-binding protein 2a
MTG infrared sounder detection chain: first radiometric test results
Dumestier, D.; Pistone, F.; Dartois, T.; Blazquez, E.
2017-11-01
Europe's next fleet of geostationary meteorological satellites, MeteoSat Third Generation, will introduce new functions in addition to continuity of high-resolution meteorological data. The atmosphere Infrared Sounder (IRS), as high -end instrument, is part of this challenging program. IRS principle is a Fourier Transform Interferometer, which allows recomposing atmospheric spectrum after infrared photons detection. Transmission spectrums will be used to support numerical weather prediction. IRS instrument is able to offer full disk coverage in one hour, an on-ground resolution of 4 by 4 km, in two spectral bands (MWIR: 1600 to 2175cm-1 and LWIR: 700 to 1210cm-1) with a spectral resolution of 0.6cm-1. Among critical technologies and processes, IRS detection chain shall offer outstanding characteristics in terms of radiometric performance like Signal to Noise Ratio (SNR), dynamic range and linearity. Selected detectors are HgCdTe two-dimensions arrays, cooled at 55 Kelvins, hybridized on snapshot silicon read-out circuit at 160x160 format. Video electronics present 16 bits resolution, and the whole detection chain (Detectors and electronics) permits to reach SNR between 2 000 and 10 000 as requested by the application. Radiometric onground test results performed on design representative detection chains are presented and are confirming the challenging phase A design choices.
A new efficient statistical test for detecting variability in the gene expression data.
Mathur, Sunil; Dolo, Samuel
2008-08-01
DNA microarray technology allows researchers to monitor the expressions of thousands of genes under different conditions. The detection of differential gene expression under two different conditions is very important in microarray studies. Microarray experiments are multi-step procedures and each step is a potential source of variance. This makes the measurement of variability difficult because approach based on gene-by-gene estimation of variance will have few degrees of freedom. It is highly possible that the assumption of equal variance for all the expression levels may not hold. Also, the assumption of normality of gene expressions may not hold. Thus it is essential to have a statistical procedure which is not based on the normality assumption and also it can detect genes with differential variance efficiently. The detection of differential gene expression variance will allow us to identify experimental variables that affect different biological processes and accuracy of DNA microarray measurements.In this article, a new nonparametric test for scale is developed based on the arctangent of the ratio of two expression levels. Most of the tests available in literature require the assumption of normal distribution, which makes them inapplicable in many situations, and it is also hard to verify the suitability of the normal distribution assumption for the given data set. The proposed test does not require the assumption of the distribution for the underlying population and hence makes it more practical and widely applicable. The asymptotic relative efficiency is calculated under different distributions, which show that the proposed test is very powerful when the assumption of normality breaks down. Monte Carlo simulation studies are performed to compare the power of the proposed test with some of the existing procedures. It is found that the proposed test is more powerful than commonly used tests under almost all the distributions considered in the study. A
The uriscreen test to detect significant asymptomatic bacteriuria during pregnancy.
Teppa, Roberto J; Roberts, James M
2005-01-01
Asymptomatic bacteriuria (ASB) occurs in 2-11% of pregnancies and it is a clear predisposition to the development of acute pyelonephritis, which, in turn, poses risk to mother and fetus. Treatment of bacteriuria during pregnancy reduces the incidence of pyelonephritis. Therefore, it is recommended to screen for ASB at the first prenatal visit. The gold standard for detection of bacteriuria during pregnancy is urine culture, but this test is expensive, time-consuming, and labor-intensive. To determine the reliability of an enzymatic urine screening test (Uriscreen; Savyon Diagnostics, Ashdod, Israel) for detecting ASB in pregnancy. Catheterized urine samples were collected from 150 women who had routine prenatal screening for ASB. Patients with urinary symptoms, active vaginal bleeding, or who were previously on antibiotics therapy were excluded from the study. Sensitivity, specificity, and the positive and negative predictive values for the Uriscreen were estimated using urine culture as the criterion standard. Urine cultures were considered positive if they grew >10(5) colony-forming units of a single uropathogen. Twenty-eight women (18.7%) had urine culture results indicating significant bacteriuria, and 17 of these 28 specimens had positive enzyme activity. Of 122 samples with no growth, 109 had negative enzyme activity. Sensitivity, specificity, and positive and negative predictive values for the Uriscreen test were 60.7% (+/-18.1), 89.3% (+/-5.6), 56.6%, and 90.8%, respectively. The Uriscreen test had inadequate sensitivity for rapid screening of bacteriuria in pregnancy.
C. A. Clausen; S. N. Kartal
2003-01-01
Early detection of wood decay is critical because decay fungi can cause rapid structural failure. The objective of this study was to compare the sensitivity of different methods purported to detect brown-rot decay in the early stages of development. The immunodiagnostic wood decay (IWD)test, soil block test/cake pan test, mechanical property tests, and chemical...
Test-day records as a tool for subclinical ketosis detection
Gantner Vesna; Potočnik K.; Jovanovac Sonja
2009-01-01
The prevalence, as well as the effect of subclinical ketosis on daily milk yield, was observed using 1.299,630 test-day records collected from January 2000 to December 2005 on 73,255 Slovenian Holstein cows. Subclinical ketosis was indicated by the fat to protein ratio (F/P ratio) higher than 1.5 in cows that yielded between 33 to 50 kg of milk per day (Eicher, 2004). The ketosis index was defined in relation to the timing of subclinical ketosis detection to the subsequent measures of test-da...
Detection of IgE insulin antibody with radioallergosorbent test
Energy Technology Data Exchange (ETDEWEB)
Nakagawa, S; Nakayama, H; Sasaki, T; Watanabe, T; Aoki, S [Hokkaido Univ., Sapporo (Japan). 2. Dept. of Medicine; Saito, N [Sapporo Railway Hospital (Japan). Dept. of Medicine
1978-01-01
An in vitro method for detecting IgE insulin antibody using the principle of the radioallergosorbent test (RAST) is described. In six patients with insulin allergy, the RAST values were higher than in normal persons or insulin-treated diabetics without insulin allergy. No differences were observed between normal persons and insulin-treated diabetics without insulin allergy. Moreover, it was observed that in one patient treated with highly purified insulin, there was a gradual decrease of RAST value parallel to the radioinsulin binding activity and clinical allergic symptoms. The RAST value of insulin is slightly inhibited by non-IgE antibodies and is, therefore, a semiquantitative value. However, the RAST is simple to perform and reproducible; it is therefore very useful in the detection of IgE insulin antibodies.
Detection of IgE insulin antibody with radioallergosorbent test
International Nuclear Information System (INIS)
Nakagawa, S.; Nakayama, H.; Sasaki, T.; Watanabe, T.; Aoki, S.; Saito, N.
1978-01-01
An in vitro method for detecting IgE insulin antibody using the principle of the radioallergosorbent test (RAST) is described. In six patients with insulin allergy, the RAST values were higher than in normal persons or insulin-treated diabetics without insulin allergy. No differences were observed between normal persons and insulin-treated diabetics without insulin allergy. Moreover, it was observed that in one patient treated with highly purified insulin, there was a gradual decrease of RAST value parallel to the radioinsulin binding activity and clinical allergic symptoms. The RAST value of insulin is slightly inhibited by non-IgE antibodies and is, therefore, a semiquantitative value. However, the RAST is simple to perform and reproducible; it is therefore very useful in the detection of IgE insulin antibodies. (orig.) [de
Directory of Open Access Journals (Sweden)
Agrawal S
2003-03-01
Full Text Available The purpose of this study was assessment of prevalence of Chlamydia trachomatis and utility of Direct Fluorescent Antibody (DFA test for its detection in male patients with non gonococcal urethritis in New Delhi , India Thirty male patients with symptoms of dysuria showing polymorphs in their gram stained urethral smears with no evidence of Neisseria gonorrhoeae, and negative for Trichomonas vaginalis and Candida albicans by wet mount were subjected to DFA test for detection of C. trachomatis in urethral samples. Microscopic examination of gram stained urethral smears revealed 5-7 polymorphs / HPF in 90% of the patients. Evidence of C. trachomatis with DFA (MicroTrak was detected in 11 cases (36.67% when a cut off of 10 elementary bodies was considered essential. It is concluded that C. trachomatis is an important cause of non gonococcal urethritis in male patients in New Delhi and DFA test is a useful diagnostic tool in its detection. Where facilities are not available for its detection antichlamydial therapy should be recommended emperically.
International Nuclear Information System (INIS)
Gao, Hongfei; Han, Jing; Yang, Shijia; Wang, Zhenxing; Wang, Lin; Fu, Zhifeng
2014-01-01
Graphical abstract: A multianalyte immunochromatographic test strip was developed for the rapid detection of two β 2 -agonists. Due to the application of chemiluminescent detection, this quantitative method shows much higher sensitivity. - Highlights: • An immunochromatographic test strip was developed for detection of multiple β 2 -agonists. • The whole assay process can be completed within 20 min. • The proposed method shows much higher sensitivity due to the application of CL detection. • It is a portable analytical tool suitable for field analysis and rapid screening. - Abstract: A novel immunochromatographic assay (ICA) was proposed for rapid and multiple assay of β 2 -agonists, by utilizing ractopamine (RAC) and salbutamol (SAL) as the models. Owing to the introduction of chemiluminescent (CL) approach, the proposed protocol shows much higher sensitivity. In this work, the described ICA was based on a competitive format, and horseradish peroxidase-tagged antibodies were used as highly sensitive CL probes. Quantitative analysis of β 2 -agonists was achieved by recording the CL signals of the probes captured on the two test zones of the nitrocellulose membrane. Under the optimum conditions, RAC and SAL could be detected within the linear ranges of 0.50–40 and 0.10–50 ng mL −1 , with the detection limits of 0.20 and 0.040 ng mL −1 (S/N = 3), respectively. The whole process for multianalyte immunoassay of RAC and SAL can be completed within 20 min. Furthermore, the test strip was validated with spiked swine urine samples and the results showed that this method was reliable in measuring β 2 -agonists in swine urine. This CL-based multianalyte test strip shows a series of advantages such as high sensitivity, ideal selectivity, simple manipulation, high assay efficiency and low cost. Thus, it opens up new pathway for rapid screening and field analysis, and shows a promising prospect in food safety
Energy Technology Data Exchange (ETDEWEB)
Gao, Hongfei; Han, Jing; Yang, Shijia; Wang, Zhenxing; Wang, Lin; Fu, Zhifeng, E-mail: fuzf@swu.edu.cn
2014-08-11
Graphical abstract: A multianalyte immunochromatographic test strip was developed for the rapid detection of two β{sub 2}-agonists. Due to the application of chemiluminescent detection, this quantitative method shows much higher sensitivity. - Highlights: • An immunochromatographic test strip was developed for detection of multiple β{sub 2}-agonists. • The whole assay process can be completed within 20 min. • The proposed method shows much higher sensitivity due to the application of CL detection. • It is a portable analytical tool suitable for field analysis and rapid screening. - Abstract: A novel immunochromatographic assay (ICA) was proposed for rapid and multiple assay of β{sub 2}-agonists, by utilizing ractopamine (RAC) and salbutamol (SAL) as the models. Owing to the introduction of chemiluminescent (CL) approach, the proposed protocol shows much higher sensitivity. In this work, the described ICA was based on a competitive format, and horseradish peroxidase-tagged antibodies were used as highly sensitive CL probes. Quantitative analysis of β{sub 2}-agonists was achieved by recording the CL signals of the probes captured on the two test zones of the nitrocellulose membrane. Under the optimum conditions, RAC and SAL could be detected within the linear ranges of 0.50–40 and 0.10–50 ng mL{sup −1}, with the detection limits of 0.20 and 0.040 ng mL{sup −1} (S/N = 3), respectively. The whole process for multianalyte immunoassay of RAC and SAL can be completed within 20 min. Furthermore, the test strip was validated with spiked swine urine samples and the results showed that this method was reliable in measuring β{sub 2}-agonists in swine urine. This CL-based multianalyte test strip shows a series of advantages such as high sensitivity, ideal selectivity, simple manipulation, high assay efficiency and low cost. Thus, it opens up new pathway for rapid screening and field analysis, and shows a promising prospect in food safety.
Detection of extended-spectrum β-lactamase in Enterobacter spp.--evaluation of six phenotypic tests.
Nogueira-Miranda, Keite da Silva; Palmeiro, Jussara Kasuko; Conte, Danieli; Maia, Fernanda Valverde; Reason, Iara Taborda de Messias; Monteiro, Cristina Leise; Dalla-Costa, Libera Maria
2012-02-01
Extended-spectrum β-lactamases (ESBL) are plasmid-mediated enzymes that hydrolyze cephalosporins and monobactams. The lack of a standard method to detect ESBL in Enterobacter spp. has led to underestimating its frequency. The aim of this study was to evaluate ESBL detection in Enterobacter spp. By the double-disk synergy test (DDST) and combined disk test (CDT) assay using cefepime, cefotaxime, and ceftazime as substrates for ESBL, plus AmpC inhibitors in different associations. A total of 83 Enterobacter spp. ESBL and 31 non-ESBL Enterobacter spp. were tested, and a cutoff point ≥3 mm was defined using a receiver operating characteristic (ROC) curve for combined disc methods. All tests showed 100% specificity. The sensitivity was 89.2% for DDST and CDT without AmpC inibitor, 90.4% in the combined disc test in Mueller-Hinton agar containing phenylboronic acid (CDT-PBAA), and 94% in the combined disc test in Mueller-Hinton agar containing cloxacillin (CDT-CLXA). Cefepime was the best substrate, mainly when AmpC inhibitors were not used. However, superior results were achieved when all cephalosporins were evaluated together. In conclusion, to improve ESBL detection in Enterobacter spp., some modifications in phenotypic tests are needed, such as to reduce the distance between the discs to 20 mm in DDST, to use a cutoff point for ≥3 mm on the CDT, and to include a cefepime disk or an inhibitor of AmpC in all tests.
Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool
Directory of Open Access Journals (Sweden)
Flávio da Silva Mesquita
2017-05-01
Full Text Available Objective: The aim of this study was to evaluate the QuickVue® RSV Test Kit (QUIDEL Corp, CA, USA as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. Methods: The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. Results: From 313 positive samples by immunofluorescence assays, 282 (90% were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue® RSV Test and viral load or specific strain. The QuickVue® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics. Resumo: Objetivo: Avaliar o teste QuickVue® RSV Test Kit (QUIDEL Corp, CA, EUA para o diagn
Boadella, M; Barasona, J A; Diaz-Sanchez, S; Lyashchenko, K P; Greenwald, R; Esfandiari, J; Gortazar, C
2012-04-01
Fallow deer (Dama dama) are widely distributed as natural or naturalised populations, as well as in game parks and deer farms. We used 157 fallow deer sampled in populations considered to be Mycobacterium tuberculosis complex (MTC) free and 73 Mycobacterium bovis-infected fallow deer confirmed postmortem by culture to evaluate the diagnostic performance of two tests for the detection of anti-mycobacterial antibodies: the dual path platform (DPP) VetTB assay and the bovine purified protein derivative (bPPD) ELISA. We also compared their sensitivity with that of the skin test, analyzed the effect of haemolysis degree on the antibody detection and described the relationship between the test readings and presence/absence of gross tuberculosis (TB) compatible lesions. Sensitivity of bPPD ELISA was 51% at a specificity of 96%. Depending on the cut-off value selected, the sensitivity of DPP VetTB ranged from 62 to 71%, while its specificity was 88-95%. In the subgroup of M. bovis-infected deer for which the skin test data were available (33 of 73); this method detected 76% of culture-positive animals, although the specificity of the intradermal test was not determined in this study. When the DPP VetTB and skin test data were combined, the resulting sensitivity obtained in this sub-group of M. bovis-infected deer increased to 97%. Gross pathology identified TB compatible lesions (TBL) in 89% culture-confirmed fallow deer. The infected animals with visible lesions had significantly higher readings in the DPP VetTB, but not in the bPPD ELISA. Only high levels of haemolysis decreased antibody test sensitivity and this effect was more evident for the bPPD ELISA. The results allowed inferring a number of management recommendations for rapid detection of MTC infection in live fallow deer and in surveys on hunter-harvested cervids. Copyright © 2011 Elsevier B.V. All rights reserved.
Research Note The reliability of a field test kit for the detection and ...
African Journals Online (AJOL)
Research Note The reliability of a field test kit for the detection and the persistence of ... Open Access DOWNLOAD FULL TEXT ... The objectives were to test a field kit for practicality and reliability, to assess the spread of the bacteria among ...
Dias, Karin Ziliotto; Jutras, Benoît; Acrani, Isabela Olszanski; Pereira, Liliane Desgualdo
2012-02-01
The aim of the present study was to assess the auditory temporal resolution ability in individuals with central auditory processing disorders, to examine the maturation effect and to investigate the relationship between the performance on a temporal resolution test with the performance on other central auditory tests. Participants were divided in two groups: 131 with Central Auditory Processing Disorder and 94 with normal auditory processing. They had pure-tone air-conduction thresholds no poorer than 15 dB HL bilaterally, normal admittance measures and presence of acoustic reflexes. Also, they were assessed with a central auditory test battery. Participants who failed at least one or more tests were included in the Central Auditory Processing Disorder group and those in the control group obtained normal performance on all tests. Following the auditory processing assessment, the Random Gap Detection Test was administered to the participants. A three-way ANOVA was performed. Correlation analyses were also done between the four Random Gap Detection Test subtests data as well as between Random Gap Detection Test data and the other auditory processing test results. There was a significant difference between the age-group performances in children with and without Central Auditory Processing Disorder. Also, 48% of children with Central Auditory Processing Disorder failed the Random Gap Detection Test and the percentage decreased as a function of age. The highest percentage (86%) was found in the 5-6 year-old children. Furthermore, results revealed a strong significant correlation between the four Random Gap Detection Test subtests. There was a modest correlation between the Random Gap Detection Test results and the dichotic listening tests. No significant correlation was observed between the Random Gap Detection Test data and the results of the other tests in the battery. Random Gap Detection Test should not be administered to children younger than 7 years old because
Balagon, Marivic F.; Maghanoy, Armi; Orcullo, Florenda M.; Cang, Marjorie; Dias, Ronaldo Ferreira; Collovati, Marco; Reed, Steven G.
2014-01-01
Leprosy remains an important health problem in a number of regions. Early detection of infection, followed by effective treatment, is critical to reduce disease progression. New sensitive and specific tools for early detection of infection will be a critical component of an effective leprosy elimination campaign. Diagnosis is made by recognizing clinical signs and symptoms, but few clinicians are able to confidently identify these. Simple tests to facilitate referral to leprosy experts are not widely available, and the correct diagnosis of leprosy is often delayed. In this report, we evaluate the performance of a new leprosy serological test (NDO-LID). As expected, the test readily detected clinically confirmed samples from patients with multibacillary (MB) leprosy, and the rate of positive results declined with bacterial burden. NDO-LID detected larger proportions of MB and paucibacillary (PB) leprosy than the alternative, the Standard Diagnostics leprosy test (87.0% versus 81.7% and 32.3% versus 6.5%, respectively), while also demonstrating improved specificity (97.4% versus 90.4%). Coupled with a new cell phone-based test reader platform (Smart Reader), the NDO-LID test provided consistent, objective test interpretation that could facilitate wider use in nonspecialized settings. In addition, results obtained from sera at the time of diagnosis, versus at the end of treatment, indicated that the quantifiable nature of this system can also be used to monitor treatment efficacy. Taken together, these data indicate that the NDO-LID/Smart Reader system can assist in the diagnosis and monitoring of MB leprosy and can detect a significant number of earlier-stage infections. PMID:24478496
DEFF Research Database (Denmark)
Liu, Jiayou; Schnyder, Manuela; Willesen, Jakob L.
2017-01-01
of the Angio Detect test kit by comparing Angio Detect testing results using serum or plasma samples with the results of Baermann-Wetzel testing using matched fecal samples. Samples from 214 dogs [with clinically suspected (N = 195) or diagnosed angiostrongylosis (N = 19)] were used for this evaluation......; sensitivity of the Angio Detect test was 97.1% (95%CI: 85.1%–99.9%). The Angio Detect test was negative for 177 of 179 samples that were negative by the Baermann-Wetzel test; specificity was 98.9% (95%CI: 96.0%–99.9%). In cross-reactivity testing, all 89 samples from dogs confirmed to be infected with other...... common nematodes (Dirofilaria immitis, D. repens, Crenosoma vulpis, hookworms, ascarids, or whipworms) were all negative for A. vasorum by the Angio Detect antigen test. Angio Detect provides a rapid and reliable method for diagnosis of A. vasorum in clinically suspected dogs at risk for infection...
Detection of lipoarabinomannan as a diagnostic test for tuberculosis.
Sada, E; Aguilar, D; Torres, M; Herrera, T
1992-01-01
A coagglutination technique was established for the detection of lipoarabinomannan of Mycobacterium tuberculosis in human serum samples and evaluated for its utility in the diagnosis of tuberculosis at the Instituto Nacional de Enfermedades Respiratorias in Mexico City. The test had a sensitivity of 88% in patients with sputum-smear-positive active pulmonary tuberculosis. The sensitivity in patients with active pulmonary tuberculosis negative for acid-fast bacilli in sputum was 67%. Less favo...
Spot test kit for explosives detection
Pagoria, Philip F; Whipple, Richard E; Nunes, Peter J; Eckels, Joel Del; Reynolds, John G; Miles, Robin R; Chiarappa-Zucca, Marina L
2014-03-11
An explosion tester system comprising a body, a lateral flow membrane swab unit adapted to be removeably connected to the body, a first explosives detecting reagent, a first reagent holder and dispenser operatively connected to the body, the first reagent holder and dispenser containing the first explosives detecting reagent and positioned to deliver the first explosives detecting reagent to the lateral flow membrane swab unit when the lateral flow membrane swab unit is connected to the body, a second explosives detecting reagent, and a second reagent holder and dispenser operatively connected to the body, the second reagent holder and dispenser containing the second explosives detecting reagent and positioned to deliver the second explosives detecting reagent to the lateral flow membrane swab unit when the lateral flow membrane swab unit is connected to the body.
BMVC test, an improved fluorescence assay for detection of malignant pleural effusions
International Nuclear Information System (INIS)
Lin, I-Ting; Tsai, Yu-Lin; Kang, Chi-Chih; Huang, Wei-Chun; Wang, Chiung-Lin; Lin, Mei-Ying; Lou, Pei-Jen; Shih, Jin-Yuan; Wang, Hao-Chien; Wu, Huey-Dong; Tsai, Tzu-Hsiu; Jan, I-Shiow; Chang, Ta-Chau
2014-01-01
The diagnosis of malignant pleural effusions is an important issue in the management of malignancy patients. Generally, cytologic examination is a routine diagnostic technique. However, morphological interpretation of cytology is sometimes inconclusive. Here an ancillary method named BMVC test is developed for rapid detection of malignant pleural effusion to improve the diagnostic accuracy at low cost. A simple assay kit is designed to collect living cells from clinical pleural effusion and a fluorescence probe, 3,6-Bis(1-methyl-4-vinylpyridinium) carbazole diiodide (BMVC), is used to illuminate malignant cells. The fluorescence intensity is quantitatively analyzed by ImageJ program. This method yields digital numbers for the test results without any grey zone or ambiguities in the current cytology tests due to intra-observer and inter-observer variability. Comparing with results from double-blind cytologic examination, this simple test gives a good discrimination between malignant and benign specimens with sensitivity of 89.4% (42/47) and specificity of 93.3% (56/60) for diagnosis of malignant pleural effusion. BMVC test provides accurate results in a short time period, and the digital output could assist cytologic examination to become more objective and clear-cut. This is a convenient ancillary tool for detection of malignant pleural effusions
Evaluation of the KEMRI Hep-cell II test kit for detection of hepatitis B ...
African Journals Online (AJOL)
To evaluate the Hep-cell II test, blood samples were collected from blood donors and processed for detection of HBsAg using Hep-cell II based on the test principle and procedure outlined by the manufacturer. ELISA Axsym HBsAg test was used as golden standard. Of the 400 samples tested, 287 (71.8%) were positive by ...
[Detection of anti-Leptospira antibodies in sera of patients in the latex agglutination test].
Volina, E G; Sarukhanova, L E; Iashina, N V; Prokopov, N I; Shkarlat, P E; Barysheva, I V
2001-01-01
The results of the preliminary evaluation of the sensitivity and specificity of the newly developed diagnostic test based on the determination of genus-specific antibodies to leptospires in the latex agglutination test, are presented. This test makes it possible to detect anti-Leptospira antibodies of any serogroup. The advantages of the developed test have been determined.
Permeated defect detecting test method and device in reactor
International Nuclear Information System (INIS)
Sakurai, Yoshishige.
1996-01-01
The present invention provides a method of and a device capable of performing a test for entire inner surfaces of the reactor upon periodical inspection of a BWR type reactor while sufficiently taking countermeasures for radiation rays into consideration. Namely, the present invention comprises following steps. (1) A provisional step for taking a shroud head of a reactor core shroud and incore structural components above and below the shroud out of the reactor, discharging reactor water and water tightly closing openings such as reactor wall perforation holes, (2) a pretreatment step for washing exposed inner surfaces of the reactor and peeling deteriorated materials, (3) a first drying step for drying portions washed and peeled in the step (2), (4) a permeation step for applying a permeation liquid of a defect detecting medium on the exposed inner surfaces of the reactor, (5) a permeation liquid removing step for removing the an excess permeation liquid in the step (4), (6) a second drying step for drying corresponding portions after performing the step (5), and (7) a flaw detecting step for optically observing the corresponding portions after performing the step (6) and detecting flaws. (I.S.)
International Nuclear Information System (INIS)
Hollik, Markus; Fietz, Walter H.; Fink, Stefan; Gehrlein, Mirko; Heller, Reinhard; Lange, Christian; Möhring, Tobias
2013-01-01
The Current Lead Test facility Karlsruhe (CuLTKa) is under construction at the Karlsruhe Institute of Technology (KIT) to perform acceptance tests of high temperature superconductor (HTS) current leads (CL). CuLTKa is in progress and present planning expects the completion in 2013. The data acquisition system is based on a modular design with electronic measurement and monitoring equipment covering a test voltage of 50 kV DC against ground. It provides plug-in units which enable temperature and voltage measurement at high voltage potential and in addition quench detection units which detect a loss of superconductivity reliably and quickly to avoid damage of the superconducting device under test. Prototype units for quench detection, temperature and voltage measurement have been successfully tested. Six temperature measurement units are already in use in the KIT test facility TOSKA and operated reliably during the acceptance tests of the HTS current leads for Wendelstein 7-X (W7-X) in 2011/2012. CuLTKa will be used first for 26 current leads which will be built in KIT for the fusion experiment JT-60SA. The present paper gives an overview of the design of the electronic measurement and quench detection equipment
Pengas, George; Dawson, Kate; Clatworthy, Philip
2009-01-01
Objective To evaluate a cognitive test, the TYM (“test your memory”), in the detection of Alzheimer’s disease. Design Cross sectional study. Setting Outpatient departments in three hospitals, including a memory clinic. Participants 540 control participants aged 18-95 and 139 patients attending a memory clinic with dementia/amnestic mild cognitive impairment. Intervention Cognitive test designed to use minimal operator time and to be suitable for non-specialist use. Main outcome measures Performance of normal controls on the TYM. Performance of patients with Alzheimer’s disease on the TYM compared with age matched controls. Validation of the TYM with two standard tests (the mini-mental state examination (MMSE) and the Addenbrooke’s cognitive examination-revised (ACE-R)). Sensitivity and specificity of the TYM in the detection of Alzheimer’s disease. Results Control participants completed the TYM with an average score of 47/50. Patients with Alzheimer’s disease scored an average of 33/50. The TYM score shows excellent correlation with the two standard tests. A score of ≤42/50 had a sensitivity of 93% and specificity of 86% in the diagnosis of Alzheimer’s disease. The TYM was more sensitive in detection of Alzheimer’s disease than the mini-mental examination, detecting 93% of patients compared with 52% for the mini-mental state exxamination. The negative and positive predictive values of the TYM with the cut off of ≤42 were 99% and 42% with a prevalence of Alzheimer’s disease of 10%. Thirty one patients with non-Alzheimer dementias scored an average of 39/50. Conclusions The TYM can be completed quickly and accurately by normal controls. It is a powerful and valid screening test for the detection of Alzheimer’s disease. PMID:19509424
Detection of person misfit in computerized adaptive tests with polytomous items
van Krimpen-Stoop, Edith; Meijer, R.R.
2000-01-01
Item scores that do not fit an assumed item response theory model may cause the latent trait value to be estimated inaccurately. For computerized adaptive tests (CAT) with dichotomous items, several person-fit statistics for detecting nonfitting item score patterns have been proposed. Both for
Wide area change detection with satellite imagery for locating underground nuclear testing
International Nuclear Information System (INIS)
Canty, M.J.; Jasani, B.; Schlittenhardt, J.
2001-01-01
With the advent of high resolution optical imagery from commercial earth observation satellites, the use of remote sensing data for verification of nuclear non-proliferation agreements is becoming increasingly attractive. Non-governmental organizations are routinely publishing high-quality imagery of sensitive nuclear installations round the world, and international verification authorities, such as the International Atomic Energy Agency (IAEA) or the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), will also want to make use, directly or indirectly, of this additional open source of information. Exact location of the sites of underground nuclear explosions is a task eminently suited to satellite imagery. Here both moderate resolutions for detecting signals in very large testing ranges as well as high resolution images for exact interpretation play important roles. We describe in our paper a particularly sensitive change detection procedure for bitemporal, multispectral satellite imagery which can be used to locate the spall zone of underground nuclear explosions with commercial satellite imagery. The method is based on the multivariate alteration detection (MAD) technique of Nielsen et al. Linear combinations of the spectral channels in two images of the same scene are chosen so as to minimize their positive correlation. This leads to a series of difference images - the so-called MAD components - which are mutually orthogonal (uncorrelated) and ordered according to decreasing variance in their pixel intensities. Since interesting changes in man-made structures may contribute minimally to the overall variance (as the latter may be dominated for instance by seasonal vegetation differences) it is often the case that such changes turn up in a higher order MAD component. This is because they will be uncorrelated with seasonal vegetation changes, stochastic image noise or other major contributions to the overall change signal. This in fact is one of the
Automation of diagnostic genetic testing: mutation detection by cyclic minisequencing.
Alagrund, Katariina; Orpana, Arto K
2014-01-01
The rising role of nucleic acid testing in clinical decision making is creating a need for efficient and automated diagnostic nucleic acid test platforms. Clinical use of nucleic acid testing sets demands for shorter turnaround times (TATs), lower production costs and robust, reliable methods that can easily adopt new test panels and is able to run rare tests in random access principle. Here we present a novel home-brew laboratory automation platform for diagnostic mutation testing. This platform is based on the cyclic minisequecing (cMS) and two color near-infrared (NIR) detection. Pipetting is automated using Tecan Freedom EVO pipetting robots and all assays are performed in 384-well micro plate format. The automation platform includes a data processing system, controlling all procedures, and automated patient result reporting to the hospital information system. We have found automated cMS a reliable, inexpensive and robust method for nucleic acid testing for a wide variety of diagnostic tests. The platform is currently in clinical use for over 80 mutations or polymorphisms. Additionally to tests performed from blood samples, the system performs also epigenetic test for the methylation of the MGMT gene promoter, and companion diagnostic tests for analysis of KRAS and BRAF gene mutations from formalin fixed and paraffin embedded tumor samples. Automation of genetic test reporting is found reliable and efficient decreasing the work load of academic personnel.
Sergeyeva, T A; Gorbach, L A; Piletska, E V; Piletsky, S A; Brovko, O O; Honcharova, L A; Lutsyk, O D; Sergeeva, L M; Zinchenko, O A; El'skaya, A V
2013-04-03
An easy-to-use colorimetric test-system for the efficient detection of creatinine in aqueous samples was developed. The test-system is based on composite molecularly imprinted polymer (MIP) membranes with artificial receptor sites capable of creatinine recognition. A thin MIP layer was created on the surface of microfiltration polyvinylidene fluoride (PVDF) membranes using method of photo-initiated grafting polymerization. The MIP layer was obtained by co-polymerization of a functional monomer (e.g. 2-acrylamido-2-methyl-1-propanesulfonic acid, itaconic acid or methacrylic acid) with N, N'-methylenebisacrylamide as a cross-linker. The choice of the functional monomer was based on the results of computational modeling. The creatinine-selective composite MIP membranes were used for measuring creatinine in aqueous samples. Creatinine molecules were selectively adsorbed by the MIP membranes and quantified using color reaction with picrates. The intensity of MIP membranes staining was proportional to creatinine concentration in an analyzed sample. The colorimetric test-system based on the composite MIP membranes was characterized with 0.25 mM detection limit and 0.25-2.5mM linear dynamic range. Storage stability of the MIP membranes was estimated as at least 1 year at room temperature. As compared to the traditional methods of creatinine detection the developed test-system is characterized by simplicity of operation, small size and low cost. Copyright © 2013 Elsevier B.V. All rights reserved.
Simonetti, Andrea; Amari, Filippo
2015-01-01
In reaction to the limitations of the traditional sterility test methods, in 2008, the U.S. Food and Drug Administration issued the guidance "Container and Closure System Integrity Testing in Lieu of Sterility Testing as a Component of the Stability Protocol for Sterile Products" encouraging sterile drug manufacturers to use properly validated physical methods, apart from conventional microbial challenge testing, to confirm container closure integrity as part of the stability protocol. The case study presented in this article investigated the capability of four container closure integrity testing methods to detect simulated defects of different sizes and types on glass syringes, prefilled both with drug product intended for parenteral administration and sterile water. The drug product was a flu vaccine (Agrippal, Novartis Vaccines, Siena, Italy). Vacuum decay, pharmacopoeial dye ingress test, Novartis specific dye ingress test, and high-voltage leak detection were, in succession, the methods involved in the comparative studies. The case study execution was preceded by the preparation of two independent sets of reference prefilled syringes, classified, respectively, as examples of conforming to closure integrity requirements (negative controls) and as defective (positive controls). Positive controls were, in turn, split in six groups, three of with holes laser-drilled through the prefilled syringe glass barrel, while the other three with capillary tubes embedded in the prefilled syringe plunger. These reference populations were then investigated by means of validated equipment used for container closure integrity testing of prefilled syringe commercial production; data were collected and analyzed to determine the detection rate and the percentage of false results. Results showed that the vacuum decay method had the highest performance in terms of detection sensitivity and also ensured the best reliability and repeatability of measurements. An innovative technical
Evaluation of the dimethylglyoxime stick test for the detection of nickel
DEFF Research Database (Denmark)
Menné, T; Andersen, Klaus Ejner; Kaaber, K
1987-01-01
The value of the dimethylglyoxime stick test for the detection of nickel was determined for 54 randomly purchased metal objects designed for prolonged skin contact, and for 15 metal alloys of known composition. Surface nickel content was determined by EDAX analysis (energy dispersive X-ray) and n...
Ekedahl, Harald; Jönsson, Bo; Annertz, Mårten; Frobell, Richard B
2018-04-01
To investigate the accuracy of 3 commonly used neurodynamic tests (slump test, straight-leg raise [SLR] test, femoral neurodynamic test) and 2 clinical assessments to determine radiculopathy (radiculopathy I, 1 neurologic sign; radiculopathy II, 2 neurologic signs corresponding to 1 specific nerve root) in detecting magnetic resonance imaging (MRI) findings (extrusion, subarticular nerve root compression, and foraminal nerve root compression). Validity study. Secondary care. We included subjects (N=99; mean age, 58y; 54% women) referred for epidural steroid injection because of lumbar radicular symptoms who had positive clinical and MRI findings. Positive clinical findings included the slump test (n=67), SLR test (n=50), femoral neurodynamic test (n=7), radiculopathy I (n=70), and radiculopathy II (n=33). Positive MRI findings included extrusion (n=27), subarticular nerve compression (n=14), and foraminal nerve compression (n=25). Not applicable. Accuracy of clinical tests in detecting MRI findings was evaluated using sensitivity, specificity, and receiver operating characteristics analysis with area under the curve (AUC). The slump test had the highest sensitivity in detecting extrusion (.78) and subarticular nerve compression (1.00), but the respective specificity was low (.36 and .38). Radiculopathy I was most sensitive in detecting foraminal nerve compression (.80) but with low specificity (.34). Only 1 assessment had a concurrent high sensitivity and specificity (ie, radiculopathy II) in detecting subarticular nerve compression (.71 and .73, respectively). The AUC for all tests in detecting extrusion, subarticular nerve compression, and foraminal nerve compression showed ranges of .48 to .60, .63 to .82, and .33 to .57, respectively. In general, the investigated neurodynamic tests or assessments for radiculopathy lacked diagnostic accuracy. The slump test was the most sensitive test, while radiculopathy II was the most specific test. Most interestingly, no
Streit, Sven; Limacher, Andreas; Zeller, Andreas; Bürge, Markus
2015-07-25
General practitioners (GPs) are in best position to suspect dementia. Mini-Mental State Examination (MMSE) and Clock Drawing Test (CDT) are widely used. Additional neurological tests may increase the accuracy of diagnosis. We aimed to evaluate diagnostic ability to detect dementia with a Short Smell Test (SST) and Palmo-Mental Reflex (PMR) in patients whose MMSE and CDT are normal, but who show signs of cognitive dysfunction. This was a 3.5-year cross-sectional observational study in the Memory Clinic of the University Department of Geriatrics in Bern, Switzerland. Participating patients with normal MMSE (>26 points) and CDT (>5 points) were referred by GPs because they suspected dementia. All were examined according to a standardized protocol. Diagnosis of dementia was based on DSM-IV TR criteria. We used SST and PMR to determine if they accurately detected dementia. In our cohort, 154 patients suspected of dementia had normal MMSE and CDT test results. Of these, 17 (11%) were demented. If SST or PMR were abnormal, sensitivity was 71% (95% CI 44-90%), and specificity 64% (95% CI 55-72%) for detecting dementia. If both tests were abnormal, sensitivity was 24% (95% CI 7-50%), but specificity increased to 93% (95% CI 88-97%). Patients suspected of dementia, but with normal MMSE and CDT results, may benefit if SST and PMR are added as diagnostic tools. If both SST and PMR are abnormal, this is a red flag to investigate these patients further, even though their negative neuropsychological screening results.
The detection limits of antimicrobial agents in cow's milk by a simple Yoghurt Culture Test.
Mohsenzadeh, M; Bahrainipour, A
2008-09-15
The aim of this study was to study performance of Yoghurt Culture Test (YCT) in the detection of antimicrobial residues in milk. For this purpose, the sensitivity of YCT for 15 antibiotics were determined. For each drug, 8 concentrations were tested. The detection limits of YCT at 2.5 h and 4 h incubation were determined (microg kg(-1)): 15 and 37.5, penicillin G; 4 and 5, ampicillin; 5 and 7.5, amoxycillin; 100 and 200, cephalexin; 80 and 100, cefazoline; 100 and 200, oxytetracycline; 500 and 100, chlortetracycline; 100 and 200, tetracycline; 150 and 200, doxycycline; 200 and 400, sulphadimidine; 500 and 1000, gentamycin; 1000 and 1500, spectinomycin; 400 and 500, erythromycin; 50 and 100, tylosin; 5000 and 10000, chloramphenicol. The YCT detection limits at 2.5 h incubation for ampicillin, cephalexin, tetracycline, oxytetracycline and tylosin are similar to those obtained as Maximum Residue Limit (MRL) according to Regulation 2377/90 EEC as set out by the European Union. In addition the detection limits of YCT for some antibiotics were lower than some of microbial inhibitor test.
Field Test Kit for Gun Residue Detection; TOPICAL
International Nuclear Information System (INIS)
WALKER, PAMELA K.; RODACY, PHILIP J.
2002-01-01
One of the major needs of the law enforcement field is a product that quickly, accurately, and inexpensively identifies whether a person has recently fired a gun--even if the suspect has attempted to wash the traces of gunpowder off. The Field Test Kit for Gunshot Residue Identification based on Sandia National Laboratories technology works with a wide variety of handguns and other weaponry using gunpowder. There are several organic chemicals in small arms propellants such as nitrocellulose, nitroglycerine, dinitrotoluene, and nitrites left behind after the firing of a gun that result from the incomplete combustion of the gunpowder. Sandia has developed a colorimetric shooter identification kit for in situ detection of gunshot residue (GSR) from a suspect. The test kit is the first of its kind and is small, inexpensive, and easily transported by individual law enforcement personnel requiring minimal training for effective use. It will provide immediate information identifying gunshot residue
Rummel, W. D.; Rathke, R. A.; Todd, P. H., Jr.; Mullen, S. J.
1975-01-01
Liquid penetrant, ultrasonic, eddy current and X-radiographic techniques were optimized and applied to the evaluation of 2219-T87 aluminum alloy test specimens in integrally stiffened panel, and weld panel configurations. Fatigue cracks in integrally stiffened panels, lack-of-fusion in weld panels, and fatigue cracks in weld panels were the flaw types used for evaluation. A 2319 aluminum alloy weld filler rod was used for all welding to produce the test specimens. Forty seven integrally stiffened panels containing a total of 146 fatigue cracks, ninety three lack-of-penetration (LOP) specimens containing a total of 239 LOP flaws, and one-hundred seventeen welded specimens containing a total of 293 fatigue cracks were evaluated. Nondestructive test detection reliability enhancement was evaluated during separate inspection sequences in the specimens in the 'as-machined or as-welded', post etched and post proof loaded conditions. Results of the nondestructive test evaluations were compared to the actual flaw size obtained by measurement of the fracture specimens after completing all inspection sequences. Inspection data were then analyzed to provide a statistical basis for determining the flaw detection reliability.
Bronchial provocation testing does not detect exercise-induced laryngeal obstruction.
Walsted, Emil Schwarz; Hull, James H; Sverrild, Asger; Porsbjerg, Celeste; Backer, Vibeke
2017-01-02
Exercise-induced laryngeal obstruction (EILO) is a key differential diagnosis for asthma in the presence of exertional respiratory symptoms. Continuous laryngoscopy during exercise (CLE), the current gold standard diagnostic test for EILO, has practical limitations. We aimed to establish if inspiratory flow data obtained during standard bronchoprovocation testing, to establish the presence of extra-thoracic hyper-responsiveness, may prove diagnostic for EILO and thus preclude requirement for CLE testing. We consecutively evaluated 37 adult subjects with exertional dyspnea and possible asthma referred over 6 months. All subjects received comprehensive assessment including a detailed clinical evaluation; pulmonary function testing, indirect and direct bronchial provocation testing, and CLE testing. Out of 37 subjects, moderate or severe EILO was diagnosed in 8 subjects (22%, all female) while 5 (14%) had both asthma and EILO. There was no correlation between degree of EILO during CLE and mean decrease in forced inspiratory flow (%FIF 50 ) obtained during neither the Methacholine (r = -0.15; p = 0.38) nor Mannitol (r = 0.04; p = 0.84) provocation tests. Inspiratory flow parameters obtained during bronchoprovocation tests did not reliably detect EILO. It remains that CLE is an important and key investigation modality in establishing a secure diagnosis of EILO.
Noninvasive Prenatal Testing and Incidental Detection of Occult Maternal Malignancies.
Bianchi, Diana W; Chudova, Darya; Sehnert, Amy J; Bhatt, Sucheta; Murray, Kathryn; Prosen, Tracy L; Garber, Judy E; Wilkins-Haug, Louise; Vora, Neeta L; Warsof, Stephen; Goldberg, James; Ziainia, Tina; Halks-Miller, Meredith
2015-07-14
Understanding the relationship between aneuploidy detection on noninvasive prenatal testing (NIPT) and occult maternal malignancies may explain results that are discordant with the fetal karyotype and improve maternal clinical care. To evaluate massively parallel sequencing data for patterns of copy-number variations that might prospectively identify occult maternal malignancies. Case series identified from 125,426 samples submitted between February 15, 2012, and September 30, 2014, from asymptomatic pregnant women who underwent plasma cell-free DNA sequencing for clinical prenatal aneuploidy screening. Analyses were conducted in a clinical laboratory that performs DNA sequencing. Among the clinical samples, abnormal results were detected in 3757 (3%); these were reported to the ordering physician with recommendations for further evaluation. NIPT for fetal aneuploidy screening (chromosomes 13, 18, 21, X, and Y). Detailed genome-wide bioinformatics analysis was performed on available sequencing data from 8 of 10 women with known cancers. Genome-wide copy-number changes in the original NIPT samples and in subsequent serial samples from individual patients when available are reported. Copy-number changes detected in NIPT sequencing data in the known cancer cases were compared with the types of aneuploidies detected in the overall cohort. From a cohort of 125,426 NIPT results, 3757 (3%) were positive for 1 or more aneuploidies involving chromosomes 13, 18, 21, X, or Y. From this set of 3757 samples, 10 cases of maternal cancer were identified. Detailed clinical and sequencing data were obtained in 8. Maternal cancers most frequently occurred with the rare NIPT finding of more than 1 aneuploidy detected (7 known cancers among 39 cases of multiple aneuploidies by NIPT, 18% [95% CI, 7.5%-33.5%]). All 8 cases that underwent further bioinformatics analysis showed unique patterns of nonspecific copy-number gains and losses across multiple chromosomes. In 1 case, blood was
False star detection and isolation during star tracking based on improved chi-square tests.
Zhang, Hao; Niu, Yanxiong; Lu, Jiazhen; Yang, Yanqiang; Su, Guohua
2017-08-01
The star sensor is a precise attitude measurement device for a spacecraft. Star tracking is the main and key working mode for a star sensor. However, during star tracking, false stars become an inevitable interference for star sensor applications, which may result in declined measurement accuracy. A false star detection and isolation algorithm in star tracking based on improved chi-square tests is proposed in this paper. Two estimations are established based on a Kalman filter and a priori information, respectively. The false star detection is operated through adopting the global state chi-square test in a Kalman filter. The false star isolation is achieved using a local state chi-square test. Semi-physical experiments under different trajectories with various false stars are designed for verification. Experiment results show that various false stars can be detected and isolated from navigation stars during star tracking, and the attitude measurement accuracy is hardly influenced by false stars. The proposed algorithm is proved to have an excellent performance in terms of speed, stability, and robustness.
Gaps-in-Noise test: gap detection thresholds in 9-year-old normal-hearing children.
Marculino, Carolina Finetti; Rabelo, Camila Maia; Schochat, Eliane
2011-12-01
To establish the standard criteria for the Gaps-in-Noise (GIN) test in 9-year-old normal-hearing children; to obtain the mean gap detection thresholds; and to verify the influence of the variables gender and ear on the gap detection thresholds. Forty normal-hearing individuals, 20 male and 20 female, with ages ranging from 9 years to 9 years and 11 months, were evaluated. The procedures performed were: anamnesis, audiological evaluation, acoustic immittance measures (tympanometry and acoustic reflex), Dichotic Digits Test, and GIN test. The results obtained were statistically analyzed. The results revealed similar performance of right and left ears in the population studied. There was also no difference regarding the variable gender. In the subjects evaluated, the mean gap detection thresholds were 4.4 ms for the right ear, and 4.2 ms for the left ear. The values obtained for right and left ear, as well as their standard deviations, can be used as standard criteria for 9-year-old children, regardless of ear or gender.
International Nuclear Information System (INIS)
Butt, T.; Butt, E.; Raza, S.
2017-01-01
This descriptive and cross-sectional study was planned to determine the dilemma of inadvertent detection of extended spectrum beta lactamase (ESBL) production in Enterobacteriaceaewhen using inhibition zone size of antibiotic disks of Cefotaxime or Aztreonam in routine antibiotic susceptibility testing as recommended by Clinical Laboratory Standards Institute (CLSI). Screening and double disk tests were adopted as per CLSI. Escherichia coli ATCC 25922 was used as control strain. Among total specimens of 5346, there were 348 isolates of Escherichia coli(n=235), Klebsiella pneumonia (n=92), Klebsiella oxytoca(n=3) or Proteus mirabilus(n=18). The screening method recommended by CLSI significantly falsely detected ESBL production in 79 (32.3%) isolates (p<0.0001). ESBL detection is important as its frequency is high and treatment of the infection varies with the presence and absence of ESBL. To avoid false reporting, proper phenotypic detection of ESBL confirmatory method-like double-disk synergy test, should be used routinely. (author)
Review: Diagnostic accuracy of PCR-based detection tests for Helicobacter Pylori in stool samples.
Khadangi, Fatemeh; Yassi, Maryam; Kerachian, Mohammad Amin
2017-12-01
Although different methods have been established to detect Helicobacter pylori (H. pylori) infection, identifying infected patients is an ongoing challenge. The aim of this meta-analysis was to provide pooled diagnostic accuracy measures for stool PCR test in the diagnosis of H. pylori infection. In this study, a systematic review and meta-analysis were carried out on various sources, including MEDLINE, Web of Sciences, and the Cochrane Library from April 1, 1999, to May 1, 2016. This meta-analysis adheres to the guidelines provided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses report (PRISMA Statement). The clinical value of DNA stool PCR test was based on the pooled false positive, false negative, true positive, and true negative of different genes. Twenty-six of 328 studies identified met the eligibility criteria. Stool PCR test had a performance of 71% (95% CI: 68-73) sensitivity, 96% (95% CI: 94-97) specificity, and 65.6 (95% CI: 30.2-142.5) diagnostic odds ratio (DOR) in diagnosis of H. pylori. The DOR of genes which showed the highest performance of stool PCR tests was as follows: 23S rRNA 152.5 (95% CI: 55.5-418.9), 16S rRNA 67.9 (95%CI: 6.4-714.3), and glmM 68.1 (95%CI: 20.1-231.7). The sensitivity and specificity of stool PCR test are relatively in the same spectrum of other diagnostic methods for the detection of H. pylori infection. In descending order of significance, the most diagnostic candidate genes using PCR detection were 23S rRNA, 16S rRNA, and glmM. PCR for 23S rRNA gene which has the highest performance could be applicable to detect H. pylori infection. © 2017 John Wiley & Sons Ltd.
Li, Qiang; Ou, Xi C; Pang, Yu; Xia, Hui; Huang, Hai R; Zhao, Bing; Wang, Sheng F; Zhao, Yan L
2017-07-01
MiniLab tuberculosis (ML TB) assay is a new automatic diagnostic tool for diagnosis of multidrug resistance tuberculosis (MDR-TB). This study was conducted with aims to know the performance of this assay. Sputum sample from 224 TB suspects was collected from tuberculosis suspects seeking medical care at Beijing Chest hospital. The sputum samples were directly used for smear and ML TB test. The left sputum sample was used to conduct Xpert MTB/RIF, Bactec MGIT culture and drug susceptibility test (DST). All discrepancies between the results from DST, molecular and phenotypic methods were confirmed by DNA Sequencing. The sensitivity and specificity of ML TB test for detecting MTBC from TB suspects were 95.1% and 88.9%, respectively. The sensitivity for smear negative TB suspects was 64.3%. For detection of RIF resistance, the sensitivity and specificity of ML TB test were 89.2% and 95.7%, respectively. For detection of INH resistance, the sensitivity and specificity of ML TB test were 78.3% and 98.1%, respectively. ML TB test showed similar performance to Xpert MTB/RIF for detection of MTBC and RIF resistance. In addition, ML TB also had good performance for INH resistance detection. Copyright © 2017. Published by Elsevier Ltd.
Ivan, M.G.; Vivet, F.; Meinders, E.R.
2010-01-01
Flexible microfluidic devices made of poly(dimethylsiloxane) (PDMS) were manufactured by soft lithography, and tested in detection of ionic species using optical absorption spectroscopy and electrical measurements. PDMS was chosen due to its flexibility and ease of surface modification by exposure
Application of functional IDDQ testing in a VLIW processor towards detection of aging degradation
Kerkhoff, Hans G.; Zhao, Yong
2015-01-01
In this paper, functional IDDQ testing has been applied for a 90nm VLIW processor to effectively detect aging degradation. This technique can provide health data for reliability evaluation as used in e.g. prognostic software for lifetime prediction. The test environment for validation, implementing
International Nuclear Information System (INIS)
Canalini, A.; Carvalho, N.C. de
1985-01-01
The non-destructive methods: Spum, Helium and Hydrostatic used in leakage detection in condenser pipelines for PWR type reactors are presented. The time, costs, sensitivity, resources necessary and personnel development factors are considered to choose adequated method, in function of nuclear power plant conditions. The leakage tests are applied in pressurized systems or vacuum. Eddy Current testing is used in condensers and steam generators aiming to avoid leakage in these equipments. The spume testing for leakage detection in condenser pipelines - which operation - and hydrostatic testing for leakage detection through reaming with shutdown - were most efficients. The Helium testing applied in pressurized systems or submitted to vacuum systems presented satisfactory results. The Eddy Current testing in condenser and steam generator pipelines reached desired objective, reducing leakage in the first and preserving the integrity in the second. (M.C.K.) [pt
Directory of Open Access Journals (Sweden)
A. D. Khomonenko
2016-07-01
Full Text Available Subject of Research.Software reliability and test planning models are studied taking into account the probabilistic nature of error detection and discovering. Modeling of software testing enables to plan the resources and final quality at early stages of project execution. Methods. Two dynamic models of processes (strategies are suggested for software testing, using error detection probability for each software module. The Erlang distribution is used for arbitrary distribution approximation of fault resolution duration. The exponential distribution is used for approximation of fault resolution discovering. For each strategy, modified labeled graphs are built, along with differential equation systems and their numerical solutions. The latter makes it possible to compute probabilistic characteristics of the test processes and states: probability states, distribution functions for fault detection and elimination, mathematical expectations of random variables, amount of detected or fixed errors. Evaluation of Results. Probabilistic characteristics for software development projects were calculated using suggested models. The strategies have been compared by their quality indexes. Required debugging time to achieve the specified quality goals was calculated. The calculation results are used for time and resources planning for new projects. Practical Relevance. The proposed models give the possibility to use the reliability estimates for each individual module. The Erlang approximation removes restrictions on the use of arbitrary time distribution for fault resolution duration. It improves the accuracy of software test process modeling and helps to take into account the viability (power of the tests. With the use of these models we can search for ways to improve software reliability by generating tests which detect errors with the highest probability.
Development of molecular tests for the detection of ILAR and latent viruses in fruit trees.
Roussel, S; Kummert, J; Dutrecq, O; Lepoivre, P; Jijakli, M H
2004-01-01
The detection throughout the year of latent and ILAR viruses in fruit tress by classical serological tests appear to be unreliable. We have developed RT-PCR tests for a reliable detection of latent and ILAR viruses in fruit trees. These assays were then simplified to allow the direct use of crude plant extracts instead of total RNA preparations, and the analyses of pooled samples. In this way, such RT-PCR protocols are suitable for a routine diagnosis of latent and ILAR viruses in fruit tree certification.
Gaudin, V; Hedou, C; Rault, A; Sanders, P; Verdon, E
2009-04-01
The screening of antimicrobial residues in eggs is an especially important subject. Three different commercial kits for the screening of sulphonamides and other antimicrobials in eggs were validated in accordance with Decision 2002/657/EC: one enzyme-linked immunoabsorbant assay (ELISA) kit multi-sulphonamides (from RAISIO Diagnostics) and two microbiological tests (a Premi test from DSM and an Explorer kit from Zeu-Inmunotec). The false-positive rates were lower than 2% for all kits. The detection capabilities (CCbeta) have to be as low as possible for banned substances and lower than the maximum residue limit (MRL) when MRLs have been set. The sensitivity of the Premi test was better than that of the Explorer test, probably because of the dilution of the eggs before the Explorer test was used. The CCbeta values towards most of the tested sulphonamides were satisfactory with the Premi test (amoxicillin, neomycin, tylosin and erythromycin were lower than their respective MRLs. Detection capabilities for sulphonamides were much lower for the ELISA kit than for microbiological tests. The ELISA kit could be recommended for the targeted screening of sulphonamides in eggs. On the other hand, the Explorer and Premi tests could be used as wide screening tests allowing the detection of most of the antimicrobial families.
Rapid detection of fumonisin B1 using a colloidal gold immunoassay strip test in corn samples.
Ling, Sumei; Wang, Rongzhi; Gu, Xiaosong; Wen, Can; Chen, Lingling; Chen, Zhibin; Chen, Qing-Ai; Xiao, Shiwei; Yang, Yanling; Zhuang, Zhenhong; Wang, Shihua
2015-12-15
Fumonisin B1 (FB1) is the most common and highest toxic of fumonisins species, exists frequently in corn and corn-based foods, leading to several animal and human diseases. Furthermore, FB1 was reported that it was associated with the human esophageal cancer. In view of the harmful of FB1, it is urgent to develop a feasible and accuracy method for rapid detection of FB1. In this study, a competitive immunoassay for FB1 detection was developed based on colloidal gold-antibody conjugate. The FB1-keyhole limpet hemoeyanin (FB1-KLH) conjugate was embedded in the test line, and goat anti-mouse IgG antibody embedded in the control line. The color density of the test line correlated with the concentration of FB1 in the range from 2.5 to 10 ng/mL, and the visual limit detection of test for FB1 was 2.5 ng/mL. The results indicated that the test strip is specific for FB1, and no cross-reactivity to other toxins. The quantitative detection for FB1 was simple, only needing one step without complicated assay performance and expensive equipment, and the total time of visual evaluation was less than 5 min. Hence, the developed colloidal gold-antibody assay can be used as a feasible method for FB1 rapid and quantitative detection in corn samples. Copyright © 2015 Elsevier Ltd. All rights reserved.
International Nuclear Information System (INIS)
Aryshev, A.; Araki, S.; Karataev, P.; Naito, T.; Terunuma, N.; Urakawa, J.
2007-01-01
A fast room temperature microwave detection system based on the Schottky Barrier-diode detector was created at the KEK ATF (Accelerator Test Facility). It was tested using Coherent Synchrotron Radiation (CSR) generated by the 1.28 GeV electron beam in the damping ring. The speed performance of the detection system was checked by observing the CSR from a multi-bunch (2.8 ns bunch separation time) beam. The theoretical estimations of CSR power yield from an edge of bending magnet as well as new injection tuning method are presented. A very high sensitivity of CSR power yield to the longitudinal electron distribution in a bunch is discussed
Energy Technology Data Exchange (ETDEWEB)
Raj, Sunny [Univ. of Central Florida, Orlando, FL (United States); Jha, Sumit Kumar [Univ. of Central Florida, Orlando, FL (United States); Pullum, Laura L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ramanathan, Arvind [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
2017-05-01
Validating the correctness of human detection vision systems is crucial for safety applications such as pedestrian collision avoidance in autonomous vehicles. The enormous space of possible inputs to such an intelligent system makes it difficult to design test cases for such systems. In this report, we present our tool MAYA that uses an error model derived from a convolutional neural network (CNN) to explore the space of images similar to a given input image, and then tests the correctness of a given human or object detection system on such perturbed images. We demonstrate the capability of our tool on the pre-trained Histogram-of-Oriented-Gradients (HOG) human detection algorithm implemented in the popular OpenCV toolset and the Caffe object detection system pre-trained on the ImageNet benchmark. Our tool may serve as a testing resource for the designers of intelligent human and object detection systems.
Detecting Chloride Contamination of Objects and Buildings – Evaluating a New Testing Process
Directory of Open Access Journals (Sweden)
Lynda Skipper
2018-02-01
Full Text Available Soluble salts play a key factor in damage to a variety of materials, including stone, ceramics and metals. Particularly, salt contamination can lead to weakening of porous materials through salt crystallisation events, and increases the rate of metal corrosion. Over time, this results in physical damage to affected objects and buildings. It is therefore important to be able to monitor the salt content of materials, in order to understand levels of salt contamination and the potential for damage to occur. This research discusses the further development of the testing method for surface chlorides originally proposed by Piechota and Drake Piechota (2016 in their article “A simple survey kit for chloride detection on cuneiform tablets and other collections”. It introduces new and revised steps into the original protocol in order to make the achieved results semi-quantifiable, as well as identifying the limits of detection of the test kit. A comparison to alternative testing methods showed that comparable results were achievable using this methodology. The revised methodology was tested for efficacy on a range of salt contaminated objects, as well as on samples from buildings.
A fluorescent immunochromatographic strip test using Quantum Dots for fumonisins detection.
Di Nardo, F; Anfossi, L; Giovannoli, C; Passini, C; Goftman, V V; Goryacheva, I Y; Baggiani, C
2016-04-01
A fluorescent immunochromatographic strip test (ICST) based on the use of Quantum Dots (QD) was developed and applied to detect fumonisins in maize samples. A limit of detection for fumonisin B1 of 2.8 µg L(-1) was achieved, with an analytical working range of 3-350 µg L(-1), corresponding to 30-3500 µg kg(-1) in maize flour samples, according with the extraction procedure. The time required to perform the analysis was 22 min, including sample preparation. Recovery values in the range from 91.4% to 105.4% with coefficients of variation not exceeding 5% were obtained for fortified and naturally contaminated maize flour samples. To evaluate the possible improvements due to the use of QD for ICST technology, we performed a direct comparison of the proposed QD-ICST to a gold nanoparticles- and a chemiluminescent-ICST previously developed for fumonisins detection, in which the same immunoreagents were employed. Copyright © 2015 Elsevier B.V. All rights reserved.
Distance-based microfluidic quantitative detection methods for point-of-care testing.
Tian, Tian; Li, Jiuxing; Song, Yanling; Zhou, Leiji; Zhu, Zhi; Yang, Chaoyong James
2016-04-07
Equipment-free devices with quantitative readout are of great significance to point-of-care testing (POCT), which provides real-time readout to users and is especially important in low-resource settings. Among various equipment-free approaches, distance-based visual quantitative detection methods rely on reading the visual signal length for corresponding target concentrations, thus eliminating the need for sophisticated instruments. The distance-based methods are low-cost, user-friendly and can be integrated into portable analytical devices. Moreover, such methods enable quantitative detection of various targets by the naked eye. In this review, we first introduce the concept and history of distance-based visual quantitative detection methods. Then, we summarize the main methods for translation of molecular signals to distance-based readout and discuss different microfluidic platforms (glass, PDMS, paper and thread) in terms of applications in biomedical diagnostics, food safety monitoring, and environmental analysis. Finally, the potential and future perspectives are discussed.
Final report on the UKAEA defect detection trials on test pieces 3 and 4. December 1982
International Nuclear Information System (INIS)
Lock, D.L.; Cowburn, K.J.
1983-03-01
The report follows ND-R-845(R) which described the scope, inspection procedures and results of the defect detection trials on test pieces 3 and 4. The work has been aimed at assessing the ability of non-destructive testing techniques, to detect and size defects near the clad/base metal interface of a flat piece and the inner radius of a PWR inlet nozzle. Following the destructive examination of the test pieces at Ispra, the true sizes of the intended defects are now known. These sizes are compared with that intended and the performance of the inspection teams reviewed. (author)
Toothpick test: a methodology for the detection of RR soybean plants1
Directory of Open Access Journals (Sweden)
Fabiana Mota da Silva
Full Text Available Due to the large increase in the area cultivated with genetically modified soybean in Brazil, it has become necessary to determine methods that are fast and efficient for detecting these cultivars. The aim of this work was to test the efficiency of the toothpick method in the detection of RR soybean plants, as well as to distinguish between cultivars, for sensitivity caused by herbicide. Ten transgenic soybean cultivars, resistant to the active ingredient glyphosate, and ten conventional soybean cultivars were used. Toothpicks soaked in glyphosate were applied to all the plants at stage V6 and evaluations were made at 2, 4, 6, 8 and 10 days after application (DAA. The effects of the glyphosate on the cultivars, and the symptoms of phytotoxicity caused in the transgenic plants were evaluated by means of grading scales. The toothpick test is effective in identifying RR soybean cultivars and also in separating them into groups by sensitivity to the symptoms caused by the glyphosate.
Gaudin, Valerie; Juhel-Gaugain, Murielle; Morétain, Jean-Pierre; Sanders, Pascal
2008-12-01
Premi Test contains viable spores of a strain of Bacillus stearothermophilus which is sensitive to antimicrobial residues, such as beta-lactams, tetracyclines, macrolides and sulphonamides. The growth of the strain is inhibited by the presence of antimicrobial residues in muscle tissue samples. Premi Test was validated according to AFNOR rules (French Association for Normalisation). The AFNOR validation was based on the comparison of reference methods (French Official method, i.e. four plate test (FPT) and the STAR protocol (five plate test)) with the alternative method (Premi Test). A preliminary study was conducted in an expert laboratory (Community Reference Laboratory, CRL) on both spiked and incurred samples (field samples). Several method performance criteria (sensitivity, specificity, relative accuracy) were estimated and are discussed, in addition to detection capabilities. Adequate agreement was found between the alternative method and the reference methods. However, Premi Test was more sensitive to beta-lactams and sulphonamides than the FPT. Subsequently, a collaborative study with 11 laboratories was organised by the CRL. Blank and spiked meat juice samples were sent to participants. The expert laboratory (CRL) statistically analysed the results. It was concluded that Premi Test could be used for the routine determination of antimicrobial residues in muscle of different animal origin with acceptable analytical performance. The detection capabilities of Premi Test for beta-lactams (amoxicillin, ceftiofur), one macrolide (tylosin) and tetracycline were at the level of the respective maximum residue limits (MRL) in muscle samples or even lower.
Airborne Turbulence Detection and Warning ACLAIM Flight Test Results
Hannon, Stephen M.; Bagley, Hal R.; Soreide, Dave C.; Bowdle, David A.; Bogue, Rodney K.; Ehernberger, L. Jack
1999-01-01
The Airborne Coherent Lidar for Advanced Inflight Measurements (ACLAIM) is a NASA/Dryden-lead program to develop and demonstrate a 2 micrometers pulsed Doppler lidar for airborne look-ahead turbulence detection and warning. Advanced warning of approaching turbulence can significantly reduce injuries to passengers and crew aboard commercial airliners. The ACLAIM instrument is a key asset to the ongoing Turbulence component of NASA's Aviation Safety Program, aimed at reducing the accident rate aboard commercial airliners by a factor of five over the next ten years and by a factor of ten over the next twenty years. As well, the advanced turbulence warning capability can prevent "unstarts" in the inlet of supersonic aircraft engines by alerting the flight control computer which then adjusts the engine to operate in a less fuel efficient, and more turbulence tolerant, mode. Initial flight tests of the ACLAIM were completed in March and April of 1998. This paper and presentation gives results from these initial flights, with validated demonstration of Doppler lidar wind turbulence detection several kilometers ahead of the aircraft.
Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool
Directory of Open Access Journals (Sweden)
Flávio da Silva Mesquita
2017-05-01
Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics.
Laser-induced fluorescence detection platform for point-of-care testing
Berner, Marcel; Hilbig, Urs; Schubert, Markus B.; Gauglitz, Günter
2017-08-01
Point-of-care testing (POCT) devices for continuous low-cost monitoring of critical patient parameters require miniaturized and integrated setups for performing quick high-sensitivity analyses, away from central clinical laboratories. This work presents a novel and promising laser-induced fluorescence platform for measurements in direct optical test formats that leads towards such powerful POCT devices based on fluorescence-labeled immunoassays. Ultimate sensitivity of thin film photodetectors, integrated with microfluidics, and a comprehensive optimization of all system components aim at low-level signal detection in the targeted biosensor application. The setup acquires fluorescence signals from the volume of a microfluidic channel. An innovative sandwiching process forms a flow channel in the microfluidic chips by embedding laser-cut double-sided adhesive tapes. The custom fit of amorphous silicon based photodiode arrays to the geometry of the flow channel enables miniaturization, fully adequate for POCT devices. A free-beam laser excitation with line focus provides excellent alignment stability, allows for easy and reliable swapping of the disposable microfluidic chips, and therewith greatly improves the ease of use of the resulting integrated device. As a proof-of-concept of this novel in-volume measurement approach, the limit of detection for the dye DY636-COOH in pure water as a model fluorophore is examined and found to be 26 nmol l-1 .
A Robust Semi-Parametric Test for Detecting Trait-Dependent Diversification.
Rabosky, Daniel L; Huang, Huateng
2016-03-01
Rates of species diversification vary widely across the tree of life and there is considerable interest in identifying organismal traits that correlate with rates of speciation and extinction. However, it has been challenging to develop methodological frameworks for testing hypotheses about trait-dependent diversification that are robust to phylogenetic pseudoreplication and to directionally biased rates of character change. We describe a semi-parametric test for trait-dependent diversification that explicitly requires replicated associations between character states and diversification rates to detect effects. To use the method, diversification rates are reconstructed across a phylogenetic tree with no consideration of character states. A test statistic is then computed to measure the association between species-level traits and the corresponding diversification rate estimates at the tips of the tree. The empirical value of the test statistic is compared to a null distribution that is generated by structured permutations of evolutionary rates across the phylogeny. The test is applicable to binary discrete characters as well as continuous-valued traits and can accommodate extremely sparse sampling of character states at the tips of the tree. We apply the test to several empirical data sets and demonstrate that the method has acceptable Type I error rates. © The Author(s) 2015. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Detection of foreign objects using bobbin probe eddy current test
Energy Technology Data Exchange (ETDEWEB)
Jung, Hee Sung; Kweon, Young Ho; Lee, Dong Ha; Shin, Wook Jo; Yim, Chan Ki [ECT Group, Sae-An Engineering Corporation, Seoul (Korea, Republic of)
2016-08-15
Residual foreign objects at the secondary side (top of the tubesheet and tube support plates) of a steam generator are likely to cause a leak by causing wear in the tube. The extent of wear is significantly affected by the material, shape, and size of the foreign object, and the corrosion properties of the tube. The presence of foreign objects at the top of the tubesheet and tube support plates has been identified using remote visual inspection methods such as the foreign object search and retrieval and eddy current test (ECT). The detection of the residual foreign object at the secondary side of a steam generator has limitations that depend on the material properties and the condition of contact with the tube. In this study, which is vertical and horizontal from the upper tubesheet, the corresponding bobbin ECT signals were collected and analyzed to measure its ability to detect foreign objects.
International Nuclear Information System (INIS)
Neurath, A.R.; Strick, N.
1983-01-01
The unavailability of serological tests for detection of several not yet characterized infectious agents transmitted by blood transfusion or by blood products prompted the development of alternative tests based on utilization of labeled nucleic acid probes specific for genomes of each of these agents. The prerequisite for the preparation of such probes is the demonstration in human plasma of nucleic acid sequences distinct from those present in host DNA or in genes of already characterized viruses occurring in plasma of infected individuals. To accomplish this, ultrasensitive tests for nucleic acids not dependent on their base sequence are needed. The authors describe a radioimmunoassay (RIA) for picogram quantities of DNA. Plasma (serum) specimens are treated with proteinase K in the presence of sodium dodecyl sulfate and extracted with phenol. Nucleic acids are precipitated with ethanol in the presence of dextran (mol.wt. approx. 5X10 5 ) as carrier. Subsequently, DNA from the redissolved samples is adsorbed onto polylysine-coated wells of microtiter plates and detected by a double-antibody RIA using anti-DNA autoantibodies from NZB/NZW mice and 125 I-labelled antibodies to mouse immunoglobulins. DNA which did not hybridize with human DNA was detected by this method in sera containing hepatitis B virus used as a model system. (Auth.)
Change Detection in High-Resolution Remote Sensing Images Using Levene-Test and Fuzzy Evaluation
Wang, G. H.; Wang, H. B.; Fan, W. F.; Liu, Y.; Liu, H. J.
2018-04-01
High-resolution remote sensing images possess complex spatial structure and rich texture information, according to these, this paper presents a new method of change detection based on Levene-Test and Fuzzy Evaluation. It first got map-spots by segmenting two overlapping images which had been pretreated, extracted features such as spectrum and texture. Then, changed information of all map-spots which had been treated by the Levene-Test were counted to obtain the candidate changed regions, hue information (H component) was extracted through the IHS Transform and conducted change vector analysis combined with the texture information. Eventually, the threshold was confirmed by an iteration method, the subject degrees of candidate changed regions were calculated, and final change regions were determined. In this paper experimental results on multi-temporal ZY-3 high-resolution images of some area in Jiangsu Province show that: Through extracting map-spots of larger difference as the candidate changed regions, Levene-Test decreases the computing load, improves the precision of change detection, and shows better fault-tolerant capacity for those unchanged regions which are of relatively large differences. The combination of Hue-texture features and fuzzy evaluation method can effectively decrease omissions and deficiencies, improve the precision of change detection.
Chromium(VI) release from leather and metals can be detected with a diphenylcarbazide spot test.
Bregnbak, David; Johansen, Jeanne D; Jellesen, Morten S; Zachariae, Claus; Thyssen, Jacob P
2015-11-01
Along with chromium, nickel and cobalt are the clinically most important metal allergens. However, unlike for nickel and cobalt, there is no validated colorimetric spot test that detects chromium. Such a test could help both clinicians and their patients with chromium dermatitis to identify culprit exposures. To evaluate the use of diphenylcarbazide (DPC) as a spot test reagent for the identification of chromium(VI) release. A colorimetric chromium(VI) spot test based on DPC was prepared and used on different items from small market surveys. The DPC spot test was able to identify chromium(VI) release at 0.5 ppm without interference from other pure metals, alloys, or leather. A market survey using the test showed no chromium(VI) release from work tools (0/100). However, chromium(VI) release from metal screws (7/60), one earring (1/50), leather shoes (4/100) and leather gloves (6/11) was observed. We found no false-positive test reactions. Confirmatory testing was performed with X-ray fluorescence (XRF) and spectrophotometrically on extraction fluids. The use of DPC as a colorimetric spot test reagent appears to be a good and valid test method for detecting the release of chromium(VI) ions from leather and metal articles. The spot test has the potential to become a valuable screening tool. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Comparison of IRT Likelihood Ratio Test and Logistic Regression DIF Detection Procedures
Atar, Burcu; Kamata, Akihito
2011-01-01
The Type I error rates and the power of IRT likelihood ratio test and cumulative logit ordinal logistic regression procedures in detecting differential item functioning (DIF) for polytomously scored items were investigated in this Monte Carlo simulation study. For this purpose, 54 simulation conditions (combinations of 3 sample sizes, 2 sample…
Tests for detecting overdispersion in models with measurement error in covariates.
Yang, Yingsi; Wong, Man Yu
2015-11-30
Measurement error in covariates can affect the accuracy in count data modeling and analysis. In overdispersion identification, the true mean-variance relationship can be obscured under the influence of measurement error in covariates. In this paper, we propose three tests for detecting overdispersion when covariates are measured with error: a modified score test and two score tests based on the proposed approximate likelihood and quasi-likelihood, respectively. The proposed approximate likelihood is derived under the classical measurement error model, and the resulting approximate maximum likelihood estimator is shown to have superior efficiency. Simulation results also show that the score test based on approximate likelihood outperforms the test based on quasi-likelihood and other alternatives in terms of empirical power. By analyzing a real dataset containing the health-related quality-of-life measurements of a particular group of patients, we demonstrate the importance of the proposed methods by showing that the analyses with and without measurement error correction yield significantly different results. Copyright © 2015 John Wiley & Sons, Ltd.
Tsoi, Kelvin K F; Chan, Joyce Y C; Hirai, Hoyee W; Wong, Adrian; Mok, Vincent C T; Lam, Linda C W; Kwok, Timothy C Y; Wong, Samuel Y S
2017-09-01
Mild cognitive impairment (MCI) is a prevalent symptom associated with the increased risk of dementia. There are many cognitive tests available for detection of MCI, and investigation of the diagnostic performance of the tests is deemed necessary. This study aims to evaluate the diagnostic performance of different cognitive tests used for MCI detection. A list of cognitive tests was identified in previous reviews and from online search engines. Literature searches were performed on each of the cognitive tests in MEDLINE, Embase, and PsycINFO from the earliest available dates of individual databases to December 31, 2016. Google Scholar was used as a supplementary search tool. Studies that were used to assess the diagnostic performance of the cognitive tests were extracted with inclusion and exclusion criteria. Each test's performance was compared with the standard diagnostic criteria. Bivariate random effects models were used to summarize the test performance as a point estimate for sensitivity and specificity, and presented in a summary receiver operating characteristic curve. Reporting quality and risk of bias were evaluated. A total of 108 studies with 23,546 participants were selected to evaluate 9 cognitive tests for MCI detection. Most of the studies used the Mini-Mental State Examination (MMSE) (n = 58) and the Montreal Cognitive Assessment (MoCA) (n = 35). The combined diagnostic performance of the MMSE in MCI detection was 0.71 sensitivity [95% confidence interval (CI): 0.66-0.75] and 0.74 specificity (95% CI: 0.70-0.78), and of the MoCA in MCI detection was 0.83 sensitivity (95% CI: 0.80-0.86) and 0.75 specificity (95% CI: 0.69-0.80). Among the 9 cognitive tests, recall tests showed the best diagnostic performance with 0.89 sensitivity (95% CI: 0.86-0.92) and 0.84 specificity (95% CI, 0.79-0.89). In subgroup analyses, long- or short-delay recall tests have shown better performance than immediate recall tests. Recall tests were shown to be the most
Karthik, K; Rathore, Rajesh; Thomas, Prasad; Arun, T R; Viswas, K N; Agarwal, R K; Manjunathachar, H V; Dhama, Kuldeep
2014-01-01
Brucella abortus, the major causative agent of abortion in cattle and a zoonotic pathogen, needs to be diagnosed at an early stage. Loop-mediated isothermal amplification (LAMP) test is easy to perform and also promising to be adapted at field level. To develop a LAMP assay for specific and rapid detection of B. abortus from clinical samples of cattle. LAMP primers were designed targeting BruAb2_0168 region using specific software tool and LAMP was optimized. The developed LAMP was tested for its specificity with 3 Brucella spp. and 11 other non-Brucella spp. Sensitivity of the developed LAMP was also carried out with known quantity of DNA. Cattle whole blood samples and aborted fetal stomach contents were collected and used for testing with developed LAMP assay and results were compared with polymerase chain reaction (PCR). The developed LAMP assay works at 61 °C for 60 min and the detection limit was observed to be 100-fold more than the conventional PCR that is commonly used for diagnosis of B. abortus. Clinical sensitivity and specificity of the developed LAMP assay was 100% when compared with Rose Bengal plate test and standard tube agglutination test. SYB® green dye I was used to visualize the result with naked eye. The novelty of the developed LAMP assay for specifically detecting B. abortus infection in cattle along with its inherent rapidness and high sensitivity can be employed for detecting this economically important pathogen of cattle at field level as well be exploited for screening of human infections.
International Nuclear Information System (INIS)
Inrig, Elizabeth; Koslowsky, Vern; Andrews, Bob; Dick, Michael; Forget, Patrick; Ing, Harry; Hugron, Roger; Wong, Larry
2011-01-01
Detection of radionuclides emitting short-range radiation, such as α and low-energy β particles, has always presented a challenge, particularly when such radionuclides are dispersed over a wide area. In this situation, conventional detection methods require the area of interest to be surveyed using a fragile probe at very close range--a slow, error-prone, and potentially dangerous process that may take many hours for a single room. The instrument under development uses a novel approach by imaging radiation-induced fluorescence in the air surrounding a contaminated area, rather than detecting the radiation directly. A robust and portable system has been designed and built that will allow contaminated areas to be rapidly detected and delineated. The detector incorporates position-sensitive photo-multiplier tubes, UV filters, a fast electronic shutter and an aspherical phase mask that significantly increases the depth-of-field. Preliminary tests have been conducted using sealed 241 Am sources of varying activities and surface areas. The details of the instrument design will be described and the results of recent testing will be presented.
Directory of Open Access Journals (Sweden)
L. V. Slogotskaya
2015-01-01
Full Text Available Explanation. Mantoux test is used to detect the tuberculous infection; however, low specificity of this method results in a high rate of false positive responses due to cross-reactions of PPD (protein purified derivate antigens contained in many mycobacterial species and Bacillus Calmette-Guerin (BCG strains. New drug Diaskintest (DST — recombinant protein CFP10-ESAT6 produced by Escherichia coli BL21(DE3/pCFP-ESAT proved to be the best acceptable diagnostic drug. The article was aimed at studying effectiveness of tuberculous recombinant allergen tests for detecting tuberculosis in the children and adolescents, who were registered in Moscow in 2013. Methods. Mantoux tests were used to examine 1,420,100 persons; positive reactions were observed in 1,020,000 children and adolescents (71,8%; 131,361 (12.9% of them were examined using DSTs. Results. Positive reactions to DST were observed in 3,304 persons (2.5% of the persons with positive reactions to Mantoux test. The tuberculosis detection rate among the persons with positive reactions to Mantoux tests using 2TU PPD-L (Leningrad Research Institute of Vaccines and Serums is 0.13%, among the persons with positive reactions to DSTs — 4.9%, i.e. 40 times more often (p = 0.000. Post-tuberculosis alterations were detected in 169 persons: in 0.13% of the persons with positive reactions to Mantoux tests using 2TU PPD-L and in 5.1% of the persons with positive reactions to DSTs (p = 0.000. Conclusion. Cohort studies conducted in Moscow demonstrated high effectiveness of Diaskintests for detecting tuberculosis in children and adolescents. High sensitivity of the method helps to detect the overwhelming majority of the persons with tuberculosis.
Directory of Open Access Journals (Sweden)
Martin Skulnick
1992-01-01
Full Text Available Detection of heterophile antibodies in infectious mononucleosis is the most rapid and cost-effective method for confirming the clinical diagnosis of the disease. This study compared seven commercial test kits (the Oxoid Infectious Mononucleosis Kit [Oxoid Ltd], Immunoscan Im-Latex [Baxter Travenol], Mono-Latex [Wampole Laboratories], Monospot and Im Screen Test [Ortho Diagnostics], Immunoscan Im-RBC Test [Baxter Travenol], and Infectious Mononucleosis Test [NCS Diagnostics] to the Davidsohn differential test. All of the kits were shown to be acceptable for use, with specificities and sensitivities greater than 96.5% and 95.5%, respectively.
Double-blind test program for astrometric planet detection with Gaia
Casertano, S.; Lattanzi, M. G.; Sozzetti, A.; Spagna, A.; Jancart, S.; Morbidelli, R.; Pannunzio, R.; Pourbaix, D.; Queloz, D.
2008-05-01
Aims: The scope of this paper is twofold. First, it describes the simulation scenarios and the results of a large-scale, double-blind test campaign carried out to estimate the potential of Gaia for detecting and measuring planetary systems. The identified capabilities are then put in context by highlighting the unique contribution that the Gaia exoplanet discoveries will be able to bring to the science of extrasolar planets in the next decade. Methods: We use detailed simulations of the Gaia observations of synthetic planetary systems and develop and utilize independent software codes in double-blind mode to analyze the data, including statistical tools for planet detection and different algorithms for single and multiple Keplerian orbit fitting that use no a priori knowledge of the true orbital parameters of the systems. Results: 1) Planets with astrometric signatures α≃ 3 times the assumed single-measurement error σ_ψ and period P≤ 5 yr can be detected reliably and consistently, with a very small number of false positives. 2) At twice the detection limit, uncertainties in orbital parameters and masses are typically 15-20%. 3) Over 70% of two-planet systems with well-separated periods in the range 0.2≤ P≤ 9 yr, astrometric signal-to-noise ratio 2≤α/σ_ψ≤ 50, and eccentricity e≤ 0.6 are correctly identified. 4) Favorable orbital configurations (both planets with P≤ 4 yr and α/σ_ψ≥ 10, redundancy over a factor of 2 in the number of observations) have orbital elements measured to better than 10% accuracy > 90% of the time, and the value of the mutual inclination angle i_rel determined with uncertainties ≤ 10°. 5) Finally, nominal uncertainties obtained from the fitting procedures are a good estimate of the actual errors in the orbit reconstruction. Extrapolating from the present-day statistical properties of the exoplanet sample, the results imply that a Gaia with σ_ψ = 8 μas, in its unbiased and complete magnitude-limited census of
Performance of blue-yellow screening test for antimicrobial detection in ovine milk.
Linage, B; Gonzalo, C; Carriedo, J A; Asensio, J A; Blanco, M A; De La Fuente, L F; San Primitivo, F
2007-12-01
Drug residues in milk are important because of public health and industrial implications. The detection limits of 25 antimicrobial agents were determined by the blue-yellow screening method in ovine milk. For each drug, 8 concentrations were tested on 20 ovine milk samples from individual ewes in midlactation. Detection limits determined by means of logistic regression were below European Union maximum residue limits (EU-MRL) for penicillin G (3 to 4 microg/kg), ceftiofur (96 to 107 microg/kg), framycetin (720 to 781 microg/kg), neomycin (915 to 1,084 microg/kg), and tylosin (44 to 51 microg/kg). Detection limits for ampicillin (5 to 6 microg/kg), cloxacillin (33 to 42 microg/kg), cefoperazone (73 to 82 microg/kg), cefalexin (160 to 202 microg/kg), gentamycin (355 to 382 microg/kg), streptomycin (3,063 to 3,593 microg/kg), tilmicosin (109 to 131 microg/kg), erythromycin (444 to 522 microg/kg), spyramicin (1,106 to 1,346 microg/kg), sulfadimethoxine (101 to 119 microg/kg), sulfathiazole (122 to 151 microg/kg), sulfamethazine (309 to 328 microg/kg), sulfanilamide (1,750 to 2,674 microg/kg), tetracycline (233 to 257 microg/kg), oxytetracycline (398 to 501 microg/kg), doxycycline (323 to 419 microg/kg), chlortetracycline (3,331 to 3,989 microg/kg), danofloxacin (4.7 to 5.5 mg/kg), enrofloxacin (41 to 46 mg/kg), and flumequin (63 to 71 mg/kg) were higher than the EU-MRL. Although the blue-yellow method showed improved sensitivity compared with other tests studied in ovine milk, the performance of screening methods for detecting antimicrobial agents in milk of this species should be improved.
Takeshita, Hikari; Yamamoto, Koichi; Nozato, Satoko; Inagaki, Tadakatsu; Tsuchimochi, Hirotsugu; Shirai, Mikiyasu; Yamamoto, Ryohei; Imaizumi, Yuki; Hongyo, Kazuhiro; Yokoyama, Serina; Takeda, Masao; Oguro, Ryosuke; Takami, Yoichi; Itoh, Norihisa; Takeya, Yasushi; Sugimoto, Ken; Fukada, So-Ichiro; Rakugi, Hiromi
2017-02-08
The conventional forelimb grip strength test is a widely used method to assess skeletal muscle function in rodents; in this study, we modified this method to improve its variability and consistency. The modified test had lower variability among trials and days than the conventional test in young C57BL6 mice, especially by improving the variabilities in male. The modified test was more sensitive than the conventional test to detect a difference in motor function between female and male mice, or between young and old male mice. When the modified test was performed on male mice during the aging process, reduction of grip strength manifested between 18 and 24 months of age at the group level and at the individual level. The modified test was similar to the conventional test in detecting skeletal muscle dysfunction in young male dystrophic mice. Thus, the modified forelimb grip strength test, with its improved validity and reliability may be an ideal substitute for the conventional method.
Directory of Open Access Journals (Sweden)
Marinka Drobnič-Košorok
2002-01-01
Full Text Available Two indirect ELISA tests developed for the detection of specific IgG in cats and rabbits, infected with M. canis and T. mentagrophytes, respectively, were evaluated and compared. The levels of specific antibodies were determined in sera of 20 cats and 25 rabbits naturally infected with M. canis and T. mentagrophytes, respectively. Infection was confirmed by the results of fungal culture. Blood samples from 12 cats and 17 rabbits, previously unexposed to dermatophytes, served as negative controls. A significant increase in the level of specific antibodies in groups of infected animals was demonstrated. Sensitivity, specificity and predictive values of a positive and a negative test were determined to evaluate the diagnostic potential. ELISA for the detection of specific antibodies in cats infected with M. canis (ELISA-cats test exhibited 75.0 % of sensitivity at 91.7 % of specificity, whereas the test for the detection of specific antibodies in rabbits, infected with T. mentagrophytes (ELISA-rabbits test is highly sensitive (96.0 % and highly specific (94.1 %, confirming its encouraging diagnostic potential. The cross-reactivity of fungal antigens was tested by performing the assays with antigens M. canis, T. mentagrophytes, M. pachydermatis and A. fumigatus. There were no significant indications of cross-reactions in the test T. mentagrophytes-rabbits, whereas strong cross-reaction between dermatophyte antigens was observed in the test M. canis-cats.
Nucleic acid tests for the detection of alpha human papillomaviruses.
Poljak, Mario; Cuzick, Jack; Kocjan, Boštjan J; Iftner, Thomas; Dillner, Joakim; Arbyn, Marc
2012-11-20
Testing for high-risk types of alpha human papillomaviruses (HPV) is an invaluable part of clinical guidelines for cervical carcinoma screening, management and treatment. In this comprehensive inventory of commercial tests for detection of alpha-HPV, we identified at least 125 distinct HPV tests and at least 84 variants of the original tests. However, only a small subset of HPV tests has documented clinical performance for any of the standard HPV testing indications. For more than 75% of HPV tests currently on the market, no single publication in peer-reviewed literature can be identified. HPV tests that have not been validated and lack proof of reliability, reproducibility and accuracy should not be used in clinical management. Once incorporated in the lab, it is essential that the whole procedure of HPV testing is subject to continuous and rigorous quality assurance to avoid sub-optimal, potentially harmful practices. Manufacturers of HPV tests are urged to put more effort into evaluating their current and future products analytically, using international standards, and for clinical applications, using clinically validated endpoints. To assist with analytical validation, the World Health Organization is developing international standards for HPV types other than HPV16 and HPV18 and is planning development of external quality control panels specifically designed to be used for performance evaluation of current and future HPV tests. There is a need for more competitively priced HPV tests, especially for resource-poor countries, and uniform test validation criteria based on international standards should enable issuing more competitive and fair tender notices for purchasing. Automation systems allowing large-scale testing, as well as further increases in clinical performance, are the main needs in the further improvement of HPV tests. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine
Schallig, H. D. F. H.; Schoone, G. J.; Beijer, E. G. M.; Kroon, C. C. M.; Hommers, M.; Ozbel, Y.; Ozensoy, S.; da Silva, E. S.; Cardoso, L. M.; da Silva, E. D.
2002-01-01
A fast agglutination screening test (FAST) for the detection of anti-Leishinania antibodies in serum samples from dogs with visceral leishmamosis was developed. The test is based on the direct agglutination test (DAT), but combines a higher parasite concentration with a smaller test volume. In
Design and test of a capacitance detection circuit based on a transimpedance amplifier
International Nuclear Information System (INIS)
Mu Linfeng; Zhang Wendong; He Changde; Zhang Rui; Song Jinlong; Xue Chenyang
2015-01-01
This paper presents a transimpedance amplifier (TIA) capacitance detection circuit aimed at detecting micro-capacitance, which is caused by ultrasonic stimulation applied to the capacitive micro-machined ultrasonic transducer (CMUT). In the capacitance interface, a TIA is adopted to amplify the received signal with a center frequency of 400 kHz, and finally detect ultrasound pressure. The circuit has a strong anti-stray property and this paper also studies the calculation of compensation capacity in detail. To ensure high resolution, noise analysis is conducted. After optimization, the detected minimum ultrasound pressure is 2.1 Pa, which is two orders of magnitude higher than the former. The test results showed that the circuit was sensitive to changes in ultrasound pressure and the distance between the CMUT and stumbling block, which also successfully demonstrates the functionality of the developed TIA of the analog-front-end receiver. (paper)
Mogeni, Polycarp; Williams, Thomas N; Omedo, Irene; Kimani, Domtila; Ngoi, Joyce M; Mwacharo, Jedida; Morter, Richard; Nyundo, Christopher; Wambua, Juliana; Nyangweso, George; Kapulu, Melissa; Fegan, Gregory; Bejon, Philip
2017-11-27
Malaria control strategies need to respond to geographical hotspots of transmission. Detection of hotspots depends on the sensitivity of the diagnostic tool used. We conducted cross-sectional surveys in 3 sites within Kilifi County, Kenya, that had variable transmission intensities. Rapid diagnostic test (RDT), microscopy, and polymerase chain reaction (PCR) were used to detect asymptomatic parasitemia, and hotspots were detected using the spatial scan statistic. Eight thousand five hundred eighty-one study participants were surveyed in 3 sites. There were statistically significant malaria hotspots by RDT, microscopy, and PCR for all sites except by microscopy in 1 low transmission site. Pooled data analysis of hotspots by PCR overlapped with hotspots by microscopy at a moderate setting but not at 2 lower transmission settings. However, variations in degree of overlap were noted when data were analyzed by year. Hotspots by RDT were predictive of PCR/microscopy at the moderate setting, but not at the 2 low transmission settings. We observed long-term stability of hotspots by PCR and microscopy but not RDT. Malaria control programs may consider PCR testing to guide asymptomatic malaria hotspot detection once the prevalence of infection falls. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.
Bonnice, W. F.; Motyka, P.; Wagner, E.; Hall, S. R.
1986-01-01
The performance of the orthogonal series generalized likelihood ratio (OSGLR) test in detecting and isolating commercial aircraft control surface and actuator failures is evaluated. A modification to incorporate age-weighting which significantly reduces the sensitivity of the algorithm to modeling errors is presented. The steady-state implementation of the algorithm based on a single linear model valid for a cruise flight condition is tested using a nonlinear aircraft simulation. A number of off-nominal no-failure flight conditions including maneuvers, nonzero flap deflections, different turbulence levels and steady winds were tested. Based on the no-failure decision functions produced by off-nominal flight conditions, the failure detection and isolation performance at the nominal flight condition was determined. The extension of the algorithm to a wider flight envelope by scheduling on dynamic pressure and flap deflection is examined. Based on this testing, the OSGLR algorithm should be capable of detecting control surface failures that would affect the safe operation of a commercial aircraft. Isolation may be difficult if there are several surfaces which produce similar effects on the aircraft. Extending the algorithm over the entire operating envelope of a commercial aircraft appears feasible.
Cardoso, Débora Morais; Gilio, Alfredo Elias; Hsin, Shieh Huei; Machado, Beatriz Marcondes; de Paulis, Milena; Lotufo, João Paulo B; Martinez, Marina Baquerizo; Grisi, Sandra Josefina E
2013-01-01
To evaluate the impact of the routine use of rapid antigen detection test in the diagnosis and treatment of acute pharyngotonsillitis in children. This is a prospective and observational study, with a protocol compliance design established at the Emergency Unit of the University Hospital of Universidade de São Paulo for the care of children and adolescents diagnosed with acute pharyngitis. 650 children and adolescents were enrolled. Based on clinical findings, antibiotics would be prescribed for 389 patients (59.8%); using the rapid antigen detection test, they were prescribed for 286 patients (44.0%). Among the 261 children who would not have received antibiotics based on the clinical evaluation, 111 (42.5%) had positive rapid antigen detection test. The diagnosis based only on clinical evaluation showed 61.1% sensitivity, 47.7% specificity, 44.9% positive predictive value, and 57.5% negative predictive value. The clinical diagnosis of streptococcal pharyngotonsillitis had low sensitivity and specificity. The routine use of rapid antigen detection test led to the reduction of antibiotic use and the identification of a risk group for complications of streptococcal infection, since 42.5% positive rapid antigen detection test patients would not have received antibiotics based only on clinical diagnosis.
DEFF Research Database (Denmark)
Craven, J.; Bjørn, H.; Barnes, E.H.
1999-01-01
This study reports a comparison between faecal egg count reduction test (FECRT), egg hatch assay (EHA) and larval development assay (LDA) for detecting anthelmintic resistance in equine strongyles. Resistance to benzimidazoles was demonstrated in 33 of 42 (79%) farms tested by FECRT and in 32 (62......%) of the 52 farms tested by EHA. As the reference strain used was not fully susceptible to benzimidazoles it was not possible to determine the level of resistance by LDA. Pyrantel resistance was indicated on three of 15 farms by faecal egg count reduction. Resistance was also indicated by LDA for one...
Test of a detection structure for a high-resolution vertex chamber
International Nuclear Information System (INIS)
Gruenewald, M.W.
1988-01-01
For the LEP experiment L3 a self-supporting detection structure in the TEC principle for the central vertex chamber was tested both with particles and with laser beams. The main topic of this thesis lied thereby on the determination of the coordinate of the particle passage along the signal-wire axis. Two different methods for the determination of this coordinate along the signal wire were studied. (orig./HSI) [de
Directory of Open Access Journals (Sweden)
Kothari Mihir
2007-01-01
Full Text Available Purpose: To assess the suitability of Brückner test as a screening test to detect significant refractive errors in children. Materials and Methods: A pediatric ophthalmologist prospectively observed the size and location of pupillary crescent on Brückner test as hyperopic, myopic or astigmatic. This was compared with the cycloplegic refraction. Detailed ophthalmic examination was done for all. Sensitivity, specificity, positive predictive value and negative predictive value of Brückner test were determined for the defined cutoff levels of ametropia. Results: Ninety-six subjects were examined. Mean age was 8.6 years (range 1 to 16 years. Brückner test could be completed for all; the time taken to complete this test was 10 seconds per subject. The ophthalmologist identified 131 eyes as ametropic, 61 as emmetropic. The Brückner test had sensitivity 91%, specificity 72.8%, positive predictive value 85.5% and negative predictive value 83.6%. Of 10 false negatives four had compound hypermetropic astigmatism and three had myopia. Conclusions: Brückner test can be used to rapidly screen the children for significant refractive errors. The potential benefits from such use may be maximized if programs use the test with lower crescent measurement cutoffs, a crescent measurement ruler and a distance fixation target.
14C-urea breath test in the detection of Helicobacter pylori infection
International Nuclear Information System (INIS)
Artiko, V.M.; Obradovic, V.B.; Petrovic, N.S.; Davidovic, B.M.; Grujic-Adanja, G.S.; Nastic-Miric, D.R.; Milosavljevic, T.N.
2001-01-01
Helicobacter pylori infection is supposed to be one of the major causes of digestive and other diseases. Among a lot of invasive and non-invasive methods for its detection, none is ideal. The aim is an assessment of the Helicobacter pylori infection in the stomach using breath test and comparison to other diagnostic methods, as well as following up the effects of therapy. In 17 patients with digestive discomfort, breath test, rapid urease test and histology were performed, while in 47 patients with proven HP infection the effect of therapy was followed up using breath test and clinical findings. Breath test was performed after per oral administration of the capsule of 14 C urea (37 kBq). Findings of the breath and urease tests were in accordance in 14/17 patients (83%) while breath test and histology in 16/17 patients (94%). During follow-up of the therapeutic effects, breath test and clinical findings were in accordance in 43/47 patients (98%). Breath test can be useful in diagnosis but is a method of choice in following up the patients after therapy for H. pylori infection, because it is non-invasive, fast and precise. (author)
Detecting a Weak Association by Testing its Multiple Perturbations: a Data Mining Approach
Lo, Min-Tzu; Lee, Wen-Chung
2014-05-01
Many risk factors/interventions in epidemiologic/biomedical studies are of minuscule effects. To detect such weak associations, one needs a study with a very large sample size (the number of subjects, n). The n of a study can be increased but unfortunately only to an extent. Here, we propose a novel method which hinges on increasing sample size in a different direction-the total number of variables (p). We construct a p-based `multiple perturbation test', and conduct power calculations and computer simulations to show that it can achieve a very high power to detect weak associations when p can be made very large. As a demonstration, we apply the method to analyze a genome-wide association study on age-related macular degeneration and identify two novel genetic variants that are significantly associated with the disease. The p-based method may set a stage for a new paradigm of statistical tests.
Green, Cameron; Hendry, Kirsty; Wilson, Elizabeth S; Walsh, Timothy; Allerhand, Mike; MacLullich, Alasdair M J; Tieges, Zoë
2017-07-01
Delirium in the ICU is associated with poor outcomes but is under-detected. Here we evaluated performance of a novel, graded test for objectively detecting inattention in delirium, implemented on a custom-built computerized device (Edinburgh Delirium Test Box-ICU). A pilot study was conducted, followed by a prospective case-control study. Royal Infirmary of Edinburgh General ICU. A pilot study was conducted in an opportunistic sample of 20 patients. This was followed by a validation study in 30 selected patients with and without delirium (median age, 63 yr; range, 23-84) who were assessed with the Edinburgh Delirium Test Box-ICU on up to 5 separate days. Presence of delirium was assessed using the Confusion Assessment Method for the ICU. The Edinburgh Delirium Test Box-ICU involves a behavioral assessment and a computerized test of attention, requiring patients to count slowly presented lights. Thirty patients were assessed a total of 79 times (n = 31, 23, 15, 8, and 2 for subsequent assessments; 38% delirious). Edinburgh Delirium Test Box-ICU scores (range, 0-11) were lower for patients with delirium than those without at the first (median, 0 vs 9.5), second (median, 3.5 vs 9), and third (median, 0 vs 10.5) assessments (all p Delirium Test Box-ICU score less than or equal to 5 was 100% sensitive and 92% specific to delirium across assessments. Longitudinally, participants' Edinburgh Delirium Test Box-ICU performance was associated with delirium status. These findings suggest that the Edinburgh Delirium Test Box-ICU has diagnostic utility in detecting ICU delirium in patients with Richmond Agitation and Sedation Scale Score greater than -3. The Edinburgh Delirium Test Box-ICU has potential additional value in longitudinally tracking attentional deficits because it provides a range of scores and is sensitive to change.
Wang, Chunying; Hou, Fei; Ma, Yicai
2015-06-15
A novel multicolor quantum dots (QDs) based immunochromatographic test strip (ICTS) was developed for simultaneous quantitative detection of multiple tumor markers, by utilizing alpha fetoprotein (AFP) and carcinoembryonic antigen (CEA) as models. The immunosensor could realize simultaneous quantitative detection of tumor markers with only one test line and one control line on the nitrocellulose membrane (NC membrane) due to the introduction of multicolor QDs. In this method, a mixture of mouse anti-AFP McAb and mouse anti-CEA McAb was coated on NC membrane as test line and goat anti-mouse IgG antibody was coated as control line. Anti-AFP McAb-QDs546 conjugates and anti-CEA McAb-QDs620 conjugates were mixed and applied to the conjugate pad. Simultaneous quantitative detection of multiple tumor markers was achieved by detecting the fluorescence intensity of captured QDs labels on test line and control line using a test strip reader. Under the optimum conditions, AFP and CEA could be detected as low as 3 ng/mL and 2 ng/mL in 15 min with a sample volume of 80 μL, and no obvious cross-reactivity was observed. The immunosensor was validated with 130 clinical samples and in which it exhibited high sensitivity (93% for AFP and 87% for CEA) and specificity (94% for AFP and 97% for CEA). The immunosensor also demonstrated high recoveries (87.5-113% for AFP and 90-97.3% for CEA) and low relative standard deviations (RSDs) (2.8-6.2% for AFP and 4.9-9.6% for CEA) when testing spiked human serum. This novel multicolor QDs based ICTS provides an easy and rapid, simultaneous quantitative detecting strategy for point-of-care testing of tumor markers. Copyright © 2014 Elsevier B.V. All rights reserved.
Antigen spot test (AST): a highly sensitive assay for the detection of antibodies
Energy Technology Data Exchange (ETDEWEB)
Herbrink, P; van Bussel, F J; Warnaar, S O [Rijksuniversiteit Leiden (Netherlands)
1982-02-12
A method is described for detection of antibodies by means of nitrocellulose or diazobenzyloxymethyl (DBM) paper on which various antigens have been spotted. The sensitivity of this antigen spot test (AST) is comparable with that of RIA and ELISA. The method requires only nanogram amounts of antigen. Since a variety of antigens can be spotted on a single piece of nitrocellulose or DBM paper, this antigen spot test is especially useful for specificity controls on antibodies.
Babbur, Vijayalakshmi; Lees, Christoph C; Goodburn, Sandra F; Morris, Nigel; Breeze, Andrew C G; Hackett, Gerald A
2005-06-01
To determine detection and false-positive rates for trisomy 21 using two-stage combined nuchal translucency (NT) and triple testing, whilst disclosing abnormal nuchal measurements at the scan. A prospective audit in a UK women's hospital, of 3188 women with singleton pregnancies, requesting screening for trisomy 21. Median age was 37 years (range 19-46). Women were offered NT screening at 11 to 14 weeks. Those with NT > or =3 mm were offered chorionic villus sampling. Those declining CVS, and those with NT risk of trisomy 21 > or = 1:250, based on age, NT, and triple test results were offered amniocentesis. Using a 3-mm NT 'cut-off' identified 16/25 cases of trisomy 21 (64%; 95% CI 38.8, 78.9). Of 2725 women who had a combined nuchal plus triple test assessment, 79 (2.6%) had a > or = 1:250 term risk of trisomy 21. Forty (1.3%) had amniocentesis identifying 6/9 remaining cases (67%:95% CI:27.9, 92.5). Overall, the detection rate was 88% (95% CI:68.8, 97.5) for a 4.8% FPR. For the screened population, to achieve an 88% detection rate using the triple test alone, the predicted FPR would be 20%. Conversely, for an FPR of 4.8% using the triple test alone, the detection rate would be only 60%. In a high-risk group, the combination of NT with triple test offers detection of trisomy 21 at least equivalent to either test, while allowing disclosure of an abnormal NT at the scan and reducing the FPR. Importantly, the FPR is less than 5%, considerably lower than expected for triple test alone for this population.
Memory detection 2.0: The first web-based memory detection test
Kleinberg, B.; Verschuere, B.
2015-01-01
There is accumulating evidence that reaction times (RTs) can be used to detect recognition of critical (e.g., crime) information. A limitation of this research base is its reliance upon small samples (average n = 24), and indications of publication bias. To advance RT-based memory detection, we
Evaluation of three commercial rapid tests for detecting antibodies to human immunodeficiency virus.
Ng, K P; Saw, T L; Baki, A; Kamarudin, R
2003-08-01
Determine HIV-1/2, Chembio HIV-1/2 STAT-PAK and PenTest are simple/rapid tests for the detection of antibodies to HIV-1 and HIV-2 in human whole blood, serum and plasma samples. The assay is one step and the result is read visually within 15 minutes. Using 92 known HIV-1 reactive sera and 108 known HIV-1 negative sera, the 3 HIV tests correctly identified all the known HIV-1 reactive and negative samples. The results indicated that Determine HIV-1/2, Chembio HIV-1/2 STAT-PAK and PenTest HIV are as sensitive and specific (100% concordance) as Microparticle Enzyme Immunoassay. The data indicated that these 3 HIV tests are effective testing systems for diagnosis of HIV infection in a situation when the conventional Enzyme Immunoassay is not suitable.
Destructive examination of test plates 1 and 2 of the defects detection trials
International Nuclear Information System (INIS)
Crutzen, S.; Buergers, W.; Violin, F.; Di Piazza, L.; Cowburn, K.; Sargent, T.
1983-01-01
A further phase of the UKAEA defect detection trials (described previously) with PWR pressure vessel steels is reported. The evaluation of NDT exercise results must be based on destructive examination of the plates used during the exercise. Tests are described and results given. (U.K.)
Energy Technology Data Exchange (ETDEWEB)
Husebye, E; O' Leary, D; Skar, V; Melby, K [Ullevaal Sykehus, Oslo (Norway)
1990-01-01
Detection of gastric campylobacter by the {sup 14}C-urea breath test and serology were correlated to biopsy culture in 25 unselected outpatients referred for gastroscopy. All the 17 culture-positive patients had positive {sup 14}C-urea breath test, and 16 had positive serology. Of eight culture-negative patients, six patients had negative breath test and seven negative serology. A high degree of reproducibility was found when two subsequent breath tests were performed in 11 healthy volunteers. The breath test values obtained at 10 min showed a strong correlation to the accumulated values within 30 min. Breath sampling once, 10 min after intake of 2.5 {mu}Ci {sup 14}C-urea, seems sufficient for the detection of gastric campylobacter. The {sup 14}C-urea breath test correlates well with biopsy culture and provides a sensitive tool for the detection of gastric campylobacter. Serology also corresponds well with biopsy culture and should provide a useful tool for epidemiologic studies. 22 refs., 4 figs., 1 tab.
Analysis of CFRP Joints by Means of T-Pull Mechanical Test and Ultrasonic Defects Detection
Directory of Open Access Journals (Sweden)
Caterina Casavola
2018-04-01
Full Text Available Defects detection within a composite component, with the aim of understanding and predicting its mechanical behavior, is of great importance in the aeronautical field because the irregularities of the composite material could compromise functionality. The aim of this paper is to detect defects by means of non-destructive testing (NDT on T-pull samples made by carbon fiber reinforced polymers (CFRP and to evaluate their effect on the mechanical response of the material. Samples, obtained from an industrial stringer having an inclined web and realized with a polymeric filler between cap and web, were subjected to ultrasonic monitoring and then to T-pull mechanical tests. All samples were tested with the same load mode and the same test configuration. An experimental set-up consisting of a semiautomatic C-scan ultrasonic mapping system with a phased array probe was designed and developed, optimizing control parameters and implementing image processing software. The present work is carried out on real composites parts that are characterized by having their intrinsic defectiveness, as opposed to the previous similar results in the literature mainly obtained on composite parts with artificially produced defects. In fact, although samples under study were realized free from defects, ultrasonic mapping found defectiveness inside the material. Moreover, the ultrasonic inspection could be useful in detecting both the location and size of defects. Experimental data were critically analyzed and qualitatively correlated with results of T-pull mechanical tests in order to better understand and explain mechanical behavior in terms of fracture mode.
Analysis of CFRP Joints by Means of T-Pull Mechanical Test and Ultrasonic Defects Detection.
Casavola, Caterina; Palano, Fania; De Cillis, Francesco; Tati, Angelo; Terzi, Roberto; Luprano, Vincenza
2018-04-18
Defects detection within a composite component, with the aim of understanding and predicting its mechanical behavior, is of great importance in the aeronautical field because the irregularities of the composite material could compromise functionality. The aim of this paper is to detect defects by means of non-destructive testing (NDT) on T-pull samples made by carbon fiber reinforced polymers (CFRP) and to evaluate their effect on the mechanical response of the material. Samples, obtained from an industrial stringer having an inclined web and realized with a polymeric filler between cap and web, were subjected to ultrasonic monitoring and then to T-pull mechanical tests. All samples were tested with the same load mode and the same test configuration. An experimental set-up consisting of a semiautomatic C-scan ultrasonic mapping system with a phased array probe was designed and developed, optimizing control parameters and implementing image processing software. The present work is carried out on real composites parts that are characterized by having their intrinsic defectiveness, as opposed to the previous similar results in the literature mainly obtained on composite parts with artificially produced defects. In fact, although samples under study were realized free from defects, ultrasonic mapping found defectiveness inside the material. Moreover, the ultrasonic inspection could be useful in detecting both the location and size of defects. Experimental data were critically analyzed and qualitatively correlated with results of T-pull mechanical tests in order to better understand and explain mechanical behavior in terms of fracture mode.
International Nuclear Information System (INIS)
Bilal, R.; Khaar, B.; Omar, M.; Qureshi, T.Z.; Ahmed, T.; Latif, Z.; Jaffery, I.; Omar, M.
2007-01-01
To compare the sensitivity, specificity and Positive Predictive Value (PPV) of histology, Campylobacter-Like Organism (CLO) test, culture and 13C-Urea Breath Test (UBT) for the diagnosis of Helicobacter pylori infection. District Headquarter Hospital, Rawalpindi, Military Hospital, Rawalpindi and Pakistan Institute of Science and Technology (PINSTECH), Nilore, Islamabad from June 2002 to 2003. Three mucosal biopsy specimens were obtained during endoscopy of 90 symptomatic patients. Histology, CLO test and culture were performed on these specimens. Breath samples for 13C-UBT were collected and sent to RIAD, PINSTECH on the same day for isotope ratio mass spectrometry. For analysis purpose, each of the tests was fixed as the gold standard in turn and the others were then compared against it. In addition, any two as well as any three positive tests were then set as the gold standard and the other tests compared against them to calculate the sensitivity, specificity, accuracy and PPV of other tests. Urea breath test had the highest sensitivity, ranging from 95 to 100%, against all the gold standards with specificity ranging from 55 to 100%, whereas the sensitivity of histological examination was around 98% but it had comparatively lower specificity (49-89%). The CLO test had a sensitivity range of 86-100% and specificity of 67-100%. Culture had the minimum sensitivity (59-70%) but had highest specificity (96-100%) against all the gold standards. Age and gender had no effect on p-value of each test or in combination. The urea breath test has shown the highest ability to detect the organism with 95-100% sensitivity in symptomatic individuals and specificity, which is comparable to other tests. (author)
A quench detection/logging system for the SSCL Magnet Test Laboratory
International Nuclear Information System (INIS)
Kim, K.; Coles, M.; Dryer, J.; Lambert, D.
1994-01-01
The quench in a magnet describes a process which occurs while the superconductivity state goes to the normal resistive state. The consequence of a quench is the conversion of the stored electromagnetic energy into heat. During this process the initiating point will reach a high temperature, which will char the insulation or melt the conductor and thereby destroy the magnet. To prevent the magnet from being lost, it is standard practice to observe several resistance and/or inductance voltages across the magnet as quench signatures - Detection. When a quench symptom is detected, protection operations are initiated: proper shutdown of the magnet excitation systems and treatment to dilute the heat energy at a spot - Protection. The temperature rise is diluted by firing heaters along the length of the magnet to ensure that the dissipated energy is spread. It is interesting that there is not a significant amount of published research on detection. To afford a more reliable quench detection system, two distinct approaches have been tried in the past: (i) Understanding of the Noise Mechanism and Sub-system Optimization, and (ii) Escaping from the Known Electromagnetic Noises by Observing Optical Waves or Acoustic Waves. The MTL of SSCL confronts a mass-measurement of about 10,000 production magnets. To meet the testing schedule, the false quench detection rate needs to be further optimized while the true quench detection rate remains secure for the magnet measurement safety. To meet these requirements, the authors followed an iterative top-down approach. First they defend the signal and noise characteristics of the quench phenomena by using existing software tools to build a rapid prototype system incorporating all proven functionality of the existing system. Then they further optimize the system through iterative upgrading based on their signal and noise character findings
Mandal, Shyamapada; Santhi, B.; Sridhar, S.; Vinolia, K.; Swaminathan, P.
2017-06-01
In this paper, an online fault detection and classification method is proposed for thermocouples used in nuclear power plants. In the proposed method, the fault data are detected by the classification method, which classifies the fault data from the normal data. Deep belief network (DBN), a technique for deep learning, is applied to classify the fault data. The DBN has a multilayer feature extraction scheme, which is highly sensitive to a small variation of data. Since the classification method is unable to detect the faulty sensor; therefore, a technique is proposed to identify the faulty sensor from the fault data. Finally, the composite statistical hypothesis test, namely generalized likelihood ratio test, is applied to compute the fault pattern of the faulty sensor signal based on the magnitude of the fault. The performance of the proposed method is validated by field data obtained from thermocouple sensors of the fast breeder test reactor.
Correlation of phenotypic tests with the presence of the blaZ gene for detection of beta-lactamase.
Ferreira, Adriano Martison; Martins, Katheryne Benini; Silva, Vanessa Rocha da; Mondelli, Alessandro Lia; Cunha, Maria de Lourdes Ribeiro de Souza da
Staphylococcus aureus and Staphylococcus saprophyticus are the most common and most important staphylococcal species associated with urinary tract infections. The objective of the present study was to compare and to evaluate the accuracy of four phenotypic methods for the detection of beta-lactamase production in Staphylococcus spp. Seventy-three strains produced a halo with a diameter ≤28mm (penicillin resistant) and all of them were positive for the blaZ gene. Among the 28 susceptible strain (halo ≥29mm), 23 carried the blaZ gene and five did not. The zone edge test was the most sensitive (90.3%), followed by MIC determination (85.5%), but the specificity of the former was low (40.0%). The nitrocefin test was the least sensitive (28.9%). However, the nitrocefin test together with the disk diffusion method showed the highest specificity (100%). The present results demonstrated that the zone edge test was the most sensitive phenotypic test for detection of beta-lactamase, although it is still not an ideal test to detect this type of resistance since its specificity was low. However, the inhibition halo diameter of the penicillin disk can be used together with the zone edge test since the same disk is employed in the two tests. Combined analysis of the two tests shows a sensitivity of 90.3% and specificity of 100%, proving better sensitivity, especially for S. saprophyticus. This is a low-cost test of easy application and interpretation that can be used in small and medium-sized laboratories where susceptibility testing is usually performed by the disk diffusion method. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.
Correlation of phenotypic tests with the presence of the blaZ gene for detection of beta-lactamase
Directory of Open Access Journals (Sweden)
Adriano Martison Ferreira
Full Text Available Abstract Staphylococcus aureus and Staphylococcus saprophyticus are the most common and most important staphylococcal species associated with urinary tract infections. The objective of the present study was to compare and to evaluate the accuracy of four phenotypic methods for the detection of beta-lactamase production in Staphylococcus spp. Seventy-three strains produced a halo with a diameter ≤28 mm (penicillin resistant and all of them were positive for the blaZ gene. Among the 28 susceptible strain (halo ≥29 mm, 23 carried the blaZ gene and five did not. The zone edge test was the most sensitive (90.3%, followed by MIC determination (85.5%, but the specificity of the former was low (40.0%. The nitrocefin test was the least sensitive (28.9%. However, the nitrocefin test together with the disk diffusion method showed the highest specificity (100%. The present results demonstrated that the zone edge test was the most sensitive phenotypic test for detection of beta-lactamase, although it is still not an ideal test to detect this type of resistance since its specificity was low. However, the inhibition halo diameter of the penicillin disk can be used together with the zone edge test since the same disk is employed in the two tests. Combined analysis of the two tests shows a sensitivity of 90.3% and specificity of 100%, proving better sensitivity, especially for S. saprophyticus. This is a low-cost test of easy application and interpretation that can be used in small and medium-sized laboratories where susceptibility testing is usually performed by the disk diffusion method.
Development of a one-step immunochromatographic strip test for the detection of sennosides A and B.
Putalun, Waraporn; Morinaga, Osamu; Tanaka, Hiroyuki; Shoyama, Yukihiro
2004-01-01
An immunochromatographic strip test was developed to detect sennoside A (1) and sennoside B (2) using anti-1 and anti-2 monoclonal antibodies. The qualitative assay was based on a competitive immunoassay in which the detector reagent consisted of colloidal gold particles coated with the respective sennoside antibodies. The capture reagents were 1- and 2-human serum albumin (HSA) conjugates immobilised on a nitrocellulose membrane on the test strip. The sample containing 1 and 2, together with detector reagent, passed over the zone where the capture reagents had been immobilised. The analytes in the sample competed for binding to the limited amount of antibodies in the detector reagent with the immobilised 1- and 2-HSA conjugates on the membrane and hence positive samples showed no colour in the capture spot zone. Detection limits for the strip test were 125 ng/mL for both sennosides. The assay system is useful as a rapid and simple screening method for the detection of 1 and 2 in plants, drugs and body fluids.
14C-urea breath test as a method to detect Campylobacter pylori colonization
Rauws, E. A.; van Royen, E. A.; Tytgat, G. N.
1989-01-01
Campylobacter pylori may cause type B gastritis. C. pylori produces urease, and the presence of this enzyme in gastric mucosal biopsies is a marker for colonization with the microorganism. The value of a breath test to detect C. pylori colonization in non-ulcer dyspepsia patients was investigated.
International Nuclear Information System (INIS)
Flezar, Margareta Strojan
2010-01-01
Light microscopic evaluation of cell morphology in preparations from urine or bladder washing containing exfoliated cells is a standard and primary method for the detection of bladder cancer and also malignancy from other parts of the urinary tract. The cytopathologic examination is a valuable method to detect an early recurrence of malignancy or new primary carcinoma during the follow-up of patients after the treatment of bladder cancer. Characteristic cellular and nuclear signs of malignancy indicate invasive or in situ urothelial carcinoma or high-grade papillary urothelial carcinoma. However, low sensitivity of the method reflects the unreliable cytopathologic diagnosis of low-grade urothelial neoplasms as cellular and nuclear signs of malignancy in these neoplasms are poorly manifested. Many different markers were developed to improve the diagnosis of bladder carcinoma on urinary samples. UroVysion™ test is among the newest and most promising tests. By the method of in situ hybridization one can detect specific cytogenetic changes of urothelial carcinoma
Detection of surface deformation and ionospheric perturbation by the North Korea nuclear test
Park, S. C.; Lee, W. J.; Sohn, D. H.; Lee, D. K.; Jung, H. S.
2017-12-01
We used remote sensing data to detect the changes on surface and ionosphere due to the North Korea nuclear test. To analyze the surface deformation before and after the 6th North Korea (NK) nuclear test, we used Satellite Aperture Radar (SAR) images. It was reported that there were some surface deformation with about 10 cm by the 4th test (Wei, 2017) and the 5th test (Jo, 2017) using Interferometric SAR (InSAR) technique. However we could not obtain surface deformation by the 6th test using InSAR with Advanced Land Observation Satellite 2 (ALOS-2) data because of low coherence in the area close to the epicenter. Although the low coherence can be occurred due to several reasons, the main reason may be large deformation in this particular case. Therefore we applied pixel offset method to measure the amount of surface deformation in the area with low coherence. Pixel offset method calculates the deformation in the directions along track and Line-of-Sight (LOS) using cross correlation of intensity of two SAR images before and after the event for a pixel and is used frequently to obtain large deformation of glacier (e.g. Lee et al., 2015). Applying pixel offset method to the area of the 6th NK nuclear test, we obtained about 3 m surface deformation in maximum. It seems that the larger deformation occurs as the mountain slope is steeper.We then analyzed ionospheric perturbation using Global Navigation Satellite System (GNSS) data. If acoustic wave by a nuclear test goes up to the ionosphere and disturbs electron density, then the changes in slant total electron content (STEC) may be detected by GNSS satellites. STEC perturbation has been reported in the previous NK nuclear tests (e.g. Park et al., 2011). We analyzed the third order derivatives of STEC for 51 GNSS stations in South Korea and found that some perturbation were appeared at 4 stations about 20 40 minutes after the test.
Drake, David; Kennedy, Rodney; Wallace, Eric
2018-02-06
Isometric multi-joint tests are considered reliable and have strong relationships with 1RM performance. However, limited evidence is available for the isometric squat in terms of effects of familiarization and reliability. This study aimed to assess, the effect of familiarization, stability reliability, determine the smallest detectible difference, and the correlation of the isometric squat test with 1RM squat performance. Thirty-six strength-trained participants volunteered to take part in this study. Following three familiarization sessions, test-retest reliability was evaluated with a 48-hour window between each time point. Isometric squat peak, net and relative force were assessed. Results showed three familiarizations were required, isometric squat had a high level of stability reliability and smallest detectible difference of 11% for peak and relative force. Isometric strength at a knee angle of ninety degrees had a strong significant relationship with 1RM squat performance. In conclusion, the isometric squat is a valid test to assess multi-joint strength and can discriminate between strong and weak 1RM squat performance. Changes greater than 11% in peak and relative isometric squat performance should be considered as meaningful in participants who are familiar with the test.
1976-04-01
The development and testing of incident detection algorithms was based on Los Angeles and Minneapolis freeway surveillance data. Algorithms considered were based on times series and pattern recognition techniques. Attention was given to the effects o...
Yang, Ming; Caterer, Nigel R; Xu, Wanhong; Goolia, Melissa
2015-09-01
Foot-and-mouth disease (FMD) is one of the world's most highly contagious animal diseases with tremendous economic consequences. A rapid and specific test for FMD diagnosis at the site of a suspected outbreak is crucial for the implementation of control measures. This project developed a multiplex lateral flow immunochromatographic strip test (multiplex-LFI) for the rapid detection and serotyping of FMD viruses. The monoclonal antibodies (mAbs) against serotypes O, A, and Asia 1 were used as capture mAbs. The mAbs were conjugated with fluorescein, rhodamine or biotin for serotype O, A and Asia 1, respectively. The detection mAbs which consisted of a serotype-independent mAb in combination with one serotype A-specific mAb and one Asia 1-specific mAb, were each colloidal gold-conjugated. The strips used in this study contained one control line and three test lines, which corresponded to one of the three serotypes, O, A or Asia 1. The newly developed multiplex-LFI strip test specifically identified serotype O (n=46), A (n=45) and Asia 1 (n=17) in all tested field isolates. The sensitivity of this strip test was comparable to the double antibody sandwich ELISA for serotypes O and A, but lower than the ELISA for serotype Asia 1. The multiplex-LFI strip test identified all tissue suspensions from animals that were experimentally inoculated with serotypes O, A or Asia 1. FMD viruses were detected in 38% and 50% of the swab samples from the lesion areas of experimentally inoculated sheep for serotypes O and A, respectively. The capability of the multiplex-LFI strip tests to produce rapid results with high specificity for FMD viruses of multiple serotypes makes this test a valuable tool to detect FMD viruses at outbreak sites. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.
Directory of Open Access Journals (Sweden)
A.V. Rodríguez
2015-07-01
Full Text Available Haemonchus contortus is a blood-sucking parasite causing the presence of faecal occult blood (FOB. The objective was to study three different FOB tests in order to have a new indicator of H. contortus infection in sheep that could be included in the genetic evaluation system as an alternative selection criterion to faecal worm egg count (FEC. A total of 29 Corriedale lambs were experimentally infected with 10.000 larvae of H. contortus. Stool samples were recorded for FEC and FOB tests (Hexagon, Hematest® and Multistix®, blood for packed cell volume (PCV, haemoglobin, white and red blood cell count (RBC, and FAMACHA© for scoring anaemia. At the end of the experiment lambs were slaughtered to worm burden count. Field infection was achieved in 309 Merino lambs under natural parasite challenge. FEC data were normalized through logarithmic transformation (LnFEC. Pearson correlation was estimated to examine the relationship between all traits. The three tests were able to detect the presence of FOB at day 11. FEC, PCV and RBC decreased to sub-normal values from day 18. FAMACHA© score 3 was considered to be indicative of anaemia. Most of the correlations were of high magnitude, with the exception of Multistix® test that was moderately correlated with haematological parameters, LnFEC and FEC. In field infection, most samples were negative to FOB tests and the correlations were lower than those calculated under experimental infection. In conclusion, FOB tests were able to detect haemonchosis earlier than FEC under high experimental parasite challenge. However, they were not able to detect FOB under natural mixed parasite challenge. FAMACHA© and PCV demonstrated to be good indicators of Haemonchosis, having moderate to high correlations with FEC.
A network based covariance test for detecting multivariate eQTL in saccharomyces cerevisiae.
Yuan, Huili; Li, Zhenye; Tang, Nelson L S; Deng, Minghua
2016-01-11
Expression quantitative trait locus (eQTL) analysis has been widely used to understand how genetic variations affect gene expressions in the biological systems. Traditional eQTL is investigated in a pair-wise manner in which one SNP affects the expression of one gene. In this way, some associated markers found in GWAS have been related to disease mechanism by eQTL study. However, in real life, biological process is usually performed by a group of genes. Although some methods have been proposed to identify a group of SNPs that affect the mean of gene expressions in the network, the change of co-expression pattern has not been considered. So we propose a process and algorithm to identify the marker which affects the co-expression pattern of a pathway. Considering two genes may have different correlations under different isoforms which is hard to detect by the linear test, we also consider the nonlinear test. When we applied our method to yeast eQTL dataset profiled under both the glucose and ethanol conditions, we identified a total of 166 modules, with each module consisting of a group of genes and one eQTL where the eQTL regulate the co-expression patterns of the group of genes. We found that many of these modules have biological significance. We propose a network based covariance test to identify the SNP which affects the structure of a pathway. We also consider the nonlinear test as considering two genes may have different correlations under different isoforms which is hard to detect by linear test.
Laboratory Tests of Multiplex Detection of PCR Amplicons Using the Luminex 100 Flow Analyzer
Energy Technology Data Exchange (ETDEWEB)
Venkateswaran, K.S.; Nasarabadi, S.; Langlois, R.G.
2000-05-05
Lawrence Livermore National Laboratory (LLNL) demonstrated the power of flow cytometry in detecting the biological agents simulants at JFT III. LLNL pioneered in the development of advanced nucleic acid analyzer (ANM) for portable real time identification. Recent advances in flow cytometry provide a means for multiplexed nucleic acid detection and immunoassay of pathogenic microorganisms. We are presently developing multiplexed immunoassays for the simultaneous detection of different simulants. Our goal is to build an integrated instrument for both nucleic acid analysis and immuno detection. In this study we evaluated the Luminex LX 100 for concurrent identification of more than one PCR amplified product. ANAA has real-time Taqman fluorescent detection capability for rapid identification of field samples. However, its multiplexing ability is limited by the combination of available fluorescent labels. Hence integration of ANAA with flow cytometry can give the rapidity of ANAA amplification and the multiplex capability of flow cytometry. Multiplexed flow cytometric analysis is made possible using a set of fluorescent latex microsphere that are individually identified by their red and infrared fluorescence. A green fluorochrome is used as the assay signal. Methods were developed for the identification of specific nucleic acid sequences from Bacillus globigii (Bg), Bacillus thuringensis (Bt) and Erwinia herbicola (Eh). Detection sensitivity using different reporter fluorochromes was tested with the LX 100, and also different assay formats were evaluated for their suitability for rapid testing. A blind laboratory trial was carried out December 22-27, 1999 to evaluate bead assays for multiplex identification of Bg and Bt PCR products. This report summarizes the assay development, fluorochrome comparisons, and the results of the blind trial conducted at LLNL for the laboratory evaluation of the LX 100 flow analyzer.
Jak, Suzanne; Oort, Frans J.; Dolan, Conor V.
2013-01-01
We present a test for cluster bias, which can be used to detect violations of measurement invariance across clusters in 2-level data. We show how measurement invariance assumptions across clusters imply measurement invariance across levels in a 2-level factor model. Cluster bias is investigated by testing whether the within-level factor loadings…
Directory of Open Access Journals (Sweden)
Daniela Meloni
Full Text Available Since 2004 it become clear that atypical bovine spongiform encephalopthies (BSEs exist in cattle. Whenever their detection has relied on active surveillance plans implemented in Europe since 2001 by rapid tests, the overall and inter-laboratory performance of these diagnostic systems in the detection of the atypical strains has not been studied thoroughly to date. To fill this gap, the present study reports on the analytical sensitivity of the EU-approved rapid tests for atypical L- and H-type and classical BSE in parallel. Each test was challenged with two dilution series, one created from a positive pool of the three BSE forms according to the EURL standard method of homogenate preparation (50% w/v and the other as per the test kit manufacturer's instructions. Multilevel logistic models and simple logistic models with the rapid test as the only covariate were fitted for each BSE form analyzed as directed by the test manufacturer's dilution protocol. The same schemes, but excluding the BSE type, were then applied to compare test performance under the manufacturer's versus the water protocol. The IDEXX HerdChek ® BSE-scrapie short protocol test showed the highest sensitivity for all BSE forms. The IDEXX® HerdChek BSE-scrapie ultra short protocol, the Prionics®--Check WESTERN and the AJ Roboscreen® BetaPrion tests showed similar sensitivities, followed by the Roche® PrionScreen, the Bio-Rad® TeSeE™ SAP and the Prionics®--Check PrioSTRIP in descending order of analytical sensitivity. Despite these differences, the limit of detection of all seven rapid tests against the different classes of material set within a 2 log(10 range of the best-performing test, thus meeting the European Food Safety Authority requirement for BSE surveillance purposes. These findings indicate that not many atypical cases would have been missed surveillance since 2001 which is important for further epidemiological interpretations of the sporadic character of
On the infrasound detected from the 2013 and 2016 DPRK's underground nuclear tests
Assink, J. D.; Averbuch, G.; Smets, P.S.M.; Evers, L.G.
2016-01-01
The underground nuclear tests by the Democratic People's Republic of Korea (DPRK) generated atmospheric infrasound both in 2013 and 2016. Clear detections were made in the Russian Federation (I45RU) and Japan (I30JP) in 2013 at stations from the International Monitoring System. Both tropospheric
Directory of Open Access Journals (Sweden)
Cheng X
2014-12-01
Full Text Available Xianglin Cheng,1,* Xu Pu,2,* Pen Jun,3 XiaoBo Zhu,3 Di Zhu,4 Ming Chen1 1Department of Laboratory Medicine, First Affiliated Hospital of Yangtze University, Jingzhou, 2Department of Laboratory Medicine, RenMin Hospital of Wuhan University, Wuhan, 3Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei, People’s Republic of China; 4Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA *These authors contributed equally to this study and share first authorship Background: Rapid immunochromatographic tests can detect disease markers in 10–15 minutes, which facilitates clinical diagnosis and treatment programs. However, most immunochromatographic tests employ gold nanoparticles as reporters, and these have only moderate sensitivity and act as qualitative methods for analyzing high biomarker concentrations. Methods: In this study, we introduce quantum dots (QDs as fluorescent probes and immunochromatographic strips to develop quantitative fluorescence point-of-care tests (QF-POCT to analyze C-reactive protein (CRP levels. Goat anti-rabbit IgG and rabbit IgG were used as control antibodies, and mouse monoclonal CRP antibody pairs were used for disease marker detection. One monoclonal CRP antibody was conjugated with QDs and served as a signal antibody, and the other monoclonal CRP antibody was dispensed onto the nitrocellulose membrane and served as a capturing antibody. In the presence of CRP, the fluorescence intensity of the monoclonal antibody-CRP-monoclonal antibody sandwich complex captured on the nitrocellulose membrane was determined using the fluorescence strip reader. Results: QF-POCT assays could quantitatively analyze the concentration of CRP in 15 minutes had a detection limit of 0.25 mg/L, and had a wide detection linearity range (0.5–300 mg/L. The intra-assay and interassay
Directory of Open Access Journals (Sweden)
W. Markotter
2009-09-01
Full Text Available Rapid immunodiagnostic test kit was evaluated against a selection of isolates of lyssavirus genotypes occurring in Africa. The test was carried out in parallel comparison with the fluorescent antibody test (FAT and isolates representing previously established phylogenetic groups from each genotype were included. The specificity of the rapid immunodiagnostic test compared favourably with the FAT and was found to detect all representatives of genotypes 1, 2, 3 and 4 in brain samples of either field cases or suckling mouse brain inoculates.
Song, Wonkeun; Hong, Seong Geun; Yong, Dongeun; Jeong, Seok Hoon; Kim, Hyun Soo; Kim, Han-Sung; Kim, Jae-Seok; Bae, Il Kwon
2015-03-01
We evaluated the combined use of the modified Hodge test (MHT) and carbapenemase inhibition test (CIT) using phenylboronic acid (PBA) and EDTA to detect carbapenemase-producing Enterobacteriaceae (CPE) and metallo-β-lactamase (MBL)-producing Pseudomonas spp. A total of 49 isolates of CPE (15 Klebsiella pneumoniae carbapenemase [KPC], 5 Guiana extended-spectrum β-lactamase [GES]-5, 9 New Delhi metallo-β-lactamase [NDM]-1, 5 Verona integron-encoded metallo-β-lactamase [VIM]-2, 3 imipenem-hydrolyzing β-lactamase [IMP], and 12 oxacillinase [OXA]-48-like), 25 isolates of MBL-producing Pseudomonas spp. (14 VIM-2 and 11 IMP), and 35 carbapenemase-negative controls were included. The MHT was performed for all isolates as recommended by the Clinical and Laboratory Standards Institute. Enhanced growth of the indicator strain was measured in mm with a ruler. The CIT was performed by directly dripping PBA and EDTA solutions onto carbapenem disks that were placed on Mueller-Hinton agar plates seeded with the test strain. Considering the results of the MHT with the ertapenem disk in Enterobacteriaceae and Pseudomonas spp., the CIT with the meropenem disk in Enterobacteriaceae, and the imipenem disk in Pseudomonas spp., three combined disk tests, namely MHT-positive plus PBA-positive, EDTA-positive, and MHT-positive plus PBA-negative plus EDTA-negative, had excellent sensitivity and specificity for the detection of KPC- (100% sensitivity and 100% specificity), MBL- (94% sensitivity and 100% specificity), and OXA-48-like-producing isolates (100% sensitivity and 100% specificity), respectively. Combined use of the MHT and CIT with PBA and EDTA, for the detection of CPE and MBL-producing Pseudomonas spp., is effective in detecting and characterizing carbapenemases in routine laboratories.
Energy Technology Data Exchange (ETDEWEB)
Zou, Zhexiang; Wang, Jun; Wang, Hua; Li, Yao Q.; Lin, Yuehe
2012-05-30
A novel electrochemical biosensing device that integrates an immunochromatographic test strip and a screen-printed electrode (SPE) connected to a portable electrochemical analyzer was presented for rapid, sensitive, and quantitative detection of disease-related biomarker in human blood samples. The principle of the sensor is based on sandwich immunoreactions between a biomarker and a pair of its antibodies on the test strip, followed by highly sensitive square-wave voltammetry (SWV) detection. Horseradish peroxidase (HRP) was used as a signal reporter for electrochemical readout. Hepatitis B surface antigen (HBsAg) was employed as a model protein biomarker to demonstrate the analytical performance of the sensor in this study. Some critical parameters governing the performance of the sensor were investigated in detail. The sensor was further utilized to detect HBsAg in human plasma with an average recovery of 91.3%. In comparison, a colorimetric immunochromatographic test strip assay (ITSA) was also conducted. The result shows that the SWV detection in the electrochemical sensor is much more sensitive for the quantitative determination of HBsAg than the colorimetric detection, indicating that such a sensor is a promising platform for rapid and sensitive point-of-care testing/screening of disease-related biomarkers in a large population
A quench detection/logging system for the SSCL Magnet Test Laboratory
International Nuclear Information System (INIS)
Kim, K.; Coles, M.; Dryer, J.; Lambert, D.
1993-05-01
The quench in a magnet describes a process which occurs while the superconductivity state goes to the normal resistive state. The consequence of a quench is the conversion of the stored electromagnetic energy into heat. During this process the initiating point will reach a high temperature, which will char the insulation or melt the conductor and thereby destroy the magnet. To prevent the magnet from being lost, it is standard practice to observe several resistance and/or inductance voltages across the magnet as quench signatures -- detection. When a quench symptom is detected, protection operations are initiated: proper shutdown of the magnet excitation systems and treatment to dilute the heat energy at a spot -- protection. The temperature rise is diluted by firing heaters along the length of the magnet to insure that the dissipated energy is spread. To develop a reliable quench detection system, two distinct approaches have been tried in the past: (i) Understanding of the Noise Mechanism and Sub-system Optimization, and (ii) Escaping from the Known Electromagnetic Noises by Observing Optical Waves or Acoustic Waves. The MTL of SSCL confronts a mass-measurement of about 10,000 production magnets. To meet the testing schedule, the false quench detection rate needs to be further optimized while the true quench detection rate remains secure for the magnet measurement safety. To meet these requirements, we followed an iterative top-down approach. First we defined the signal and noise characteristics of the quench phenomena by using existing software tools to build a rapid prototype system incorporating all proven functionality of the existing system. Then we further optimize the system through iterative upgrading based on our signal and noise character findings
Directory of Open Access Journals (Sweden)
Luzia Helena Queiroz da Silva
2002-03-01
Full Text Available The detection of rabies antibodies is extremely valuable for epidemiological studies, determination of immune status in man, animals, and for the diagnosis of the disease. Several serological procedures have been described for this purpose. The present study reports a comparison between counterimmunoelectrophoresis test (CIET and mouse neutralization test (MNT in the detection of antibodies against rabies virus from 212 serum samples of vaccinated dogs. The agreement between both techniques was 79.7% and a significative association was demonstrated. The correlation coefficients between MNT and the CIET titers was determined considering 88 samples showing positive results in both techniques [CIET = 2 and MNT = 5 (0.13 IU/ml] and resulted r² = 0.7926 (p < 0.001. The performance of CIET system was technically simple, cheap and rapid, and thereby it could be useful for serological monitoring of dog vaccination campaigns as well as for individual analysis.
DEFF Research Database (Denmark)
Overbye, Marie Birch
2017-01-01
Aims: A central paradigm of global anti-doping policy is detection-based deterrence, i.e. the risk of testing and exclusion from sport are effective doping deterrents. This paper investigates how elite athletes perceive the deterrent effect of the testing strategy in their sport and explores...... the likelihood of testing nor detection as deterrents. 8% did not consider the likelihood of testing and detection nor the ban from sport as deterrents. Conclusions: Testing programmes–as a strategy to detect and deter doping–are no great deterrent for many athletes. The results highlight the limitations...... whether and how specific factors such as the frequency of testing influence athletes’ perceptions of testing as a deterrent. Methods: 645 Danish elite athletes completed a web-based questionnaire about their perceptions of testing efforts in their sport. Findings: 75% of the athletes considered...
Wang, Mian; Liu, Xiaomei; Lu, Huizhe; Wang, Hongmei; Qin, Zhaohai
2015-01-21
A "turn-on" fluorescent and colorimetric chemosensor (RBS) for Pd(2+) has been designed and synthesized through introduction of sulfur as a ligand atom to Rhodamine B. RBS exhibits high selectivity (freedom from the interference of Hg(2+ )in particular) and sensitivity toward Pd(2+) with a detection limit as low as 2.4 nM. RBS is also a reversible sensor, and it can be made into test paper to detect Pd(2+) in pure water. Compared to the chemosensors that introduced phosphorus to Rhodamine to detect Pd(2+), RBS can be synthesized more simply and economically.
Chromium(VI) release from leather and metals can be detected with a diphenylcarbazide spot test
DEFF Research Database (Denmark)
Bregnbak, David; Johansen, Jeanne D.; Jellesen, Morten Stendahl
2015-01-01
Along with chromium, nickel and cobalt are the clinically most important metal allergens. However, unlike for nickel and cobalt, there is no validated colorimetric spot test that detects chromium. Such a test could help both clinicians and their patients with chromium dermatitis to identify culprit...... exposures. To evaluate the use of diphenylcarbazide (DPC) as a spot test reagent for the identification of chromium(VI) release. A colorimetric chromium(VI) spot test based on DPC was prepared and used on different items from small market surveys. The DPC spot test was able to identify chromium(VI) release...
Bond, Ashley; Burkitt, Michael D; Cox, Trevor; Smart, Howard L; Probert, Chris; Haslam, Neil; Sarkar, Sanchoy
2017-03-01
In the UK, the majority of diagnostic upper gastrointestinal (UGI) endoscopies are a result of direct-to-test referral from the primary care physician. The diagnostic yield of these tests is relatively low, and the burden high on endoscopy services. Dual-focus magnification, high-definition endoscopy is expected to improve detection and classification of UGI mucosal lesions and also help minimize biopsies by allowing better targeting. This is a retrospective study of patients attending for direct-to-test UGI endoscopy from January 2015 to June 2015. The primary outcome of interest was the identification of significant pathology. Detection of significant pathology was modelled using logistic regression. 500 procedures were included. The mean age of patients was 61.5 (±15.6) years; 60.8% of patients were female. Ninety-four gastroscopies were performed using dual-focus magnification high-definition endoscopy. Increasing age, male gender, type of endoscope, and type of operator were all identified as significant factors influencing the odds of detecting significant mucosal pathology. Use of dual-focus magnification, high-definition endoscopy was associated with an odds ratio of 1.87 (95%CI 1.11-3.12) favouring the detection of significant pathology. Subsequent analysis suggested that the increased detection of pathology during dual-focus magnification, high-definition endoscopy also influenced patient follow-up and led to a 3.0 fold (p=0.04) increase in the proportion of patients entered into an UGI endoscopic surveillance program. Dual-focus magnification, high-definition endoscopy improved the diagnostic yield for significant mucosal pathology in patients referred for direct-to-test endoscopy. If this finding is recapitulated elsewhere it will have substantial impact on the provision of UGI endoscopic services.
Engler, K. H.; Efstratiou, A.; Norn, D.; Kozlov, R. S.; Selga, I.; Glushkevich, T. G.; Tam, M.; Melnikov, V. G.; Mazurova, I. K.; Kim, V. E.; Tseneva, G. Y.; Titov, L. P.; George, R. C.
2002-01-01
An immunochromatographic strip (ICS) test was developed for the detection of diphtheria toxin by using an equine polyclonal antibody as the capture antibody and colloidal gold-labeled monoclonal antibodies specific for fragment A of the diphtheria toxin molecule as the detection antibody. The ICS test has been fully optimized for the detection of toxin from bacterial cultures; the limit of detection was approximately 0.5 ng of diphtheria toxin per ml within 10 min. In a comparative study with 915 pure clinical isolates of Corynebacterium spp., the results of the ICS test were in complete agreement with those of the conventional Elek test. The ICS test was also evaluated for its ability to detect toxigenicity from clinical specimens (throat swabs) in two field studies conducted within areas of the former USSR where diphtheria is epidemic. Eight hundred fifty throat swabs were examined by conventional culture and by use of directly inoculated broth cultures for the ICS test. The results showed 99% concordance (848 of 850 specimens), and the sensitivity and specificity of the ICS test were 98% (95% confidence interval, 91 to 99%) and 99% (95% confidence interval, 99 to 100%), respectively. PMID:11773096
Detection of anti neutrophil antibodies by radio-iodinated protein A binding test
International Nuclear Information System (INIS)
Cartron, J.; Muller, J.Y.; Tchernia, G.; Paule, B.; Varet, B.
1983-01-01
The granulocyte associated IgG in normal and neutropenic subjects has been determined by a direct quantitative assay using radiolabeled staphylococcal protein A. This assay allows to postulate an immunological mechanism to explain the neutropenia in 19 cases of neutropenias associated with malfunctions of the immune system and in 4 cases of idiopathic neutropenias. Discussed in this report is the possible interaction of immune complexes bound in vivo to the granulocytes. By an immunofluorescence test, it has been possible to detect IgG or IgM antibodies in only 52% of patients with a positive direct assay. The determination of granulocyte-associated IgG is therefore a better indicator for defining an auto-immune neutropenia than the detection of free antibodies in the sera [fr
Validation of the shake test for detecting freeze damage to adsorbed vaccines.
Kartoglu, Umit; Ozgüler, Nejat Kenan; Wolfson, Lara J; Kurzatkowski, Wiesław
2010-08-01
To determine the validity of the shake test for detecting freeze damage in aluminium-based, adsorbed, freeze-sensitive vaccines. A double-blind crossover design was used to compare the performance of the shake test conducted by trained health-care workers (HCWs) with that of phase contrast microscopy as a "gold standard". A total of 475 vials of 8 different types of World Health Organization prequalified freeze-sensitive vaccines from 10 different manufacturers were used. Vaccines were kept at 5 degrees C. Selected numbers of vials from each type were then exposed to -25 degrees C and -2 degrees C for 24-hour periods. There was complete concordance between HCWs and phase-contrast microscopy in identifying freeze-damaged vials and non-frozen samples. Non-frozen samples showed a fine-grain structure under phase contrast microscopy, but freeze-damaged samples showed large conglomerates of massed precipitates with amorphous, crystalline, solid and needle-like structures. Particles in the non-frozen samples measured from 1 microm (vaccines against diphtheria-tetanus-pertussis; Haemophilus influenzae type b; hepatitis B; diphtheria-tetanus-pertussis-hepatitis B) to 20 microm (diphtheria and tetanus vaccines, alone or in combination). By contrast, aggregates in the freeze-damaged samples measured up to 700 microm (diphtheria-tetanus-pertussis) and 350 microm on average. The shake test had 100% sensitivity, 100% specificity and 100% positive predictive value in this study, which confirms its validity for detecting freeze damage to aluminium-based freeze-sensitive vaccines.
DEFF Research Database (Denmark)
Canty, M.; Jahnke, G.; Nielsen, Allan Aasbjerg
2005-01-01
The analysis of open-source satellite imagery is in process of establishing itself as an important tool for monitoring nuclear activities throughout the world which are relevant to disarmament treaties, like e. g. the Comprehensive Nuclear-Test-Ban Treaty (CTBT). However, the detection of anthrop......The analysis of open-source satellite imagery is in process of establishing itself as an important tool for monitoring nuclear activities throughout the world which are relevant to disarmament treaties, like e. g. the Comprehensive Nuclear-Test-Ban Treaty (CTBT). However, the detection...... of conventional multispectral satellite platforms with moderate ground resolution (Landsat TM, ASTER) to detect changes over wide areas.We chose the Nevada Test Site (NTS), USA, for a case study because of the large amount of available ground truth information. The analysis is based on the multivariate alteration...
Hasan, J A; Huq, A; Nair, G B; Garg, S; Mukhopadhyay, A K; Loomis, L; Bernstein, D; Colwell, R R
1995-11-01
We report on the development and testing of two monoclonal antibody-based rapid immunodiagnostic test kits, BengalScreen, a coagglutination test, and Bengal DFA, a direct fluorescent-antibody test, for direct detection of Vibrio cholerae O139 synonym Bengal in clinical and environmental specimens. The BengalScreen test requires less than 5 min to complete and can be used in the field. Bengal DFA, being more sensitive than BengalScreen, requires only one reagent and less than 20 min for detection and enumeration of V. cholerae O139 synonym Bengal. In tests for specificity, all 40 strains of V. cholerae O139 reacted with both test kits, whereas 157 strains of heterologous species examined did not, yielding 100% specificity in this study. A field trial was conducted in with both BengalScreen and Bengal DFA, and the results were compared with those obtained by conventional culture methods. BengalScreen demonstrated a sensitivity of 95%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 94%. Results obtained by Bengal DFA, on the other hand, were 100% sensitive and 100% specific and yielded 100% positive and negative predictive values compared with culture methods. In a second evaluation, 93 stool specimens from Mexico that were negative for V. cholerae O139 by culture were also tested with both the BengalScreen and Bengal DFA kits. None of the 93 specimens were positive for V. cholerae O139 by both tests. A concentration method was optimized for screening of environmental water samples for V. cholerae O139 synonym Bengal with rapid test kits. BengalScreen results were unequivocally positive when water samples contained at least 2.0 x 10(3) CFU/ml, whereas Bengal DFA demonstrated an unequivocally positive reaction when the water sample contained at least 1.5 x 10(2) CFU/ml. When Bengal DFA was compared with conventional culture methods for enumeration of V. cholerae O139 synonym Bengal organisms, no difference was observed.
Kuzmenko, E T; Labigina, A V; Leshenko, O Ya; Rusanov, D N; Kuzmenko, V V; Fedko, L P; Pak, I P
2015-05-01
The analysis of results of screening (n = 3208; sexually active citizen aged from 18 to 59 years) was carried out to detect oncogene types of human papilloma virus in using qualitative (1150 females and 720 males) and quantitative (polymerase chain reaction in real-time (843 females and 115 males) techniques. The human papilloma virus of high oncogene type was detected in 65% and 68.4% of females and in 48.6% and 53% of males correspondingly. Among 12 types of human papilloma virus the most frequently diagnosed was human papilloma virus 16 independently of gender of examined and technique of analysis. In females, under application of qualitative tests rate of human papilloma virus 16 made up to 18.3% (n = 280) and under application of quantitative tests Rte of human papilloma virus made up to 14.9% (n = 126; p ≤ 0.05). Under examination of males using qualitative tests rate of human papilloma virus 16 made up to 8.3% (n = 60) and under application of qualitative tests made up to 12.2% (n = 14; p ≥ 0.05). Under application of qualitative tests rate of detection on the rest ofoncogene types of human papilloma virus varied in females from 3.4% to 8.4% and in males from 1.8% to 5.9%. Under application of qualitative tests to females rate of human papilloma virus with high viral load made up to 68.4%, with medium viral load - 2.85% (n = 24) and with low viral load -0.24% (n = 2). Under application of quantitative tests in males rate of detection of types of human papilloma virus made up to 53% and at that in all high viral load was established. In females, the most of oncogene types of human papilloma virus (except for 31, 39, 59) are detected significantly more often than in males.
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg; Conradsen, Knut; Skriver, Henning
2017-01-01
Based on an omnibus likelihood ratio test statistic for the equality of several variance-covariance matrices following the complex Wishart distribution and a factorization of this test statistic with associated p-values, change analysis in a time series of multilook polarimetric SAR data...... in the covariance matrix representation is carried out. The omnibus test statistic and its factorization detect if and when change occurs. Using airborne EMISAR and spaceborne RADARSAT-2 data this paper focuses on change detection based on the p-values, on visualization of change at pixel as well as segment level......, and on computer software....
Energy Technology Data Exchange (ETDEWEB)
Broddegaard, Mattias [Siemens Industrial Turbines, Finspaang (Sweden)
2004-12-01
Components in gas turbines, steam turbines and boilers are subjected to both high and low cycle fatigue. The lifetime of components is established by calculations based on conservative assumptions and safety factors, which means that most components will have a real life far exceeding the calculated. Conventional nondestructive testing is aimed at detecting macroscopic defects, such as cracks, inclusions and other discontinuities in the material. By having the possibility of detecting damage at a microscopic level, the risk of fractures in components subjected to fatigue can be reduced and the interval between testing occasions can be extended. The project goal has been to establish knowledge about possibilities and limitations for early detection of low and high cycle fatigue damage, by a literature survey and by practical experiments on low cycle fatigue specimens in 12% Cr-steel, for the following nondestructive testing methods: MWM (Meandering Winding Magnetometer) eddy current testing; and Nonlinear ultrasonics, both classical (second harmonic) and non-classical (crack closure). The project started with a literature survey. This resulted in a proposal for specimen design and selection of testing techniques and project partners. Manufacturing of specimens in 12% Cr-steel, designation X22CrMoV12-1, and low cycle fatigue testing at 300 deg C testing temperature was carried out at Siemens Industrial Turbines in Finspaang. Specimens with 0, 25, 50, 75 and 100% consumed life, based on the number of cycles to presence of macroscopic cracks, were produced. MWM eddy current testing was carried out by Jentek Sensors Inc. in the USA. Measurements with nonlinear ultrasonics were carried out by Siemens Corporate Technology in Munich and at Blekinge Univ. The specimens were finally examined in SEM and light optical microscope in Finspaang. In the literature, results showing that early detection of fatigue damage by nondestructive testing is possible, can be found. By
USE OF-EPR-DL FIELD TEST EQUIPMENT FOR DETECTION OF SIGMA PHASE
Directory of Open Access Journals (Sweden)
Abraão Danilo Gomes Barreto
2014-06-01
Full Text Available This work has objective to correlate the intergranular corrosion susceptibility test named EPR-DL (Electrochemical Potentiokinetic Reactivation of Double Loop with the sigma phase formation and other phases. It has been used samples from a UNS S32760 steel pipe for conducting various aging heat treatments. Held isothermal heat treatment at 850°C for 1 min, 10 min, 30 min, 1 h, 1h30min and 10 h. Each heat treated sample and as received were tested using the electrochemical polarization reactivation of double loop technique (EPR-DL. It was possible the detection of deleterious phases with DL-EPR portable cell. The EPR-DL test of some samples showed a second peak of reactivation in which the results showed that this peak might be associated with ferrite or be related to the presence of chi phase
Testing the applicability of rapid on-site enzymatic activity detection for surface water monitoring
Stadler, Philipp; Vogl, Wolfgang; Juri, Koschelnik; Markus, Epp; Maximilian, Lackner; Markus, Oismüller; Monika, Kumpan; Peter, Strauss; Regina, Sommer; Gabriela, Ryzinska-Paier; Farnleitner Andreas, H.; Matthias, Zessner
2015-04-01
On-site detection of enzymatic activities has been suggested as a rapid surrogate for microbiological pollution monitoring of water resources (e.g. using glucuronidases, galactosidases, esterases). Due to the possible short measuring intervals enzymatic methods have high potential as near-real time water quality monitoring tools. This presentation describes results from a long termed field test. For twelve months, two ColiMinder devices (Vienna Water Monitoring, Austria) for on-site determination of enzymatic activity were tested for stream water monitoring at the experimental catchment HOAL (Hydrological Open Air Laboratory, Center for Water Resource Systems, Vienna University of Technology). The devices were overall able to follow and reflect the diverse hydrological and microbiological conditions of the monitored stream during the test period. Continuous data in high temporal resolution captured the course of enzymatic activity in stream water during diverse rainfall events. The method also proofed sensitive enough to determine diurnal fluctuations of enzymatic activity in stream water during dry periods. The method was able to capture a seasonal trend of enzymatic activity in stream water that matches the results gained from Colilert18 analysis for E. coli and coliform bacteria of monthly grab samples. Furthermore the comparison of ColiMinder data with measurements gained at the same test site with devices using the same method but having different construction design (BACTcontrol, microLAN) showed consistent measuring results. Comparative analysis showed significant differences between measured enzymatic activity (modified fishman units and pmol/min/100ml) and cultivation based analyses (most probable number, colony forming unit). Methods of enzymatic activity measures are capable to detect ideally the enzymatic activity caused by all active target bacteria members, including VBNC (viable but nonculturable) while cultivation based methods cannot detect VBNC
Omnibus test for change detection in a time sequence of polarimetric SAR data
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg; Conradsen, Knut; Skriver, Henning
2016-01-01
in the covariance matrix representation is carried out. The omnibus test statistic and its factorization detect if and when change(s) occur. The technique is demonstrated on airborne EMISAR C-band data but may be applied to ALOS, COSMO-SkyMed, RadarSat-2, Sentinel-1, TerraSAR-X, and Yoagan or other dual- and quad...
Detection of Answer Copying Based on the Structure of a High-Stakes Test
Belov, Dmitry I.
2011-01-01
This article presents the Variable Match Index (VM-Index), a new statistic for detecting answer copying. The power of the VM-Index relies on two-dimensional conditioning as well as the structure of the test. The asymptotic distribution of the VM-Index is analyzed by reduction to Poisson trials. A computational study comparing the VM-Index with the…
Poisson Approximation-Based Score Test for Detecting Association of Rare Variants.
Fang, Hongyan; Zhang, Hong; Yang, Yaning
2016-07-01
Genome-wide association study (GWAS) has achieved great success in identifying genetic variants, but the nature of GWAS has determined its inherent limitations. Under the common disease rare variants (CDRV) hypothesis, the traditional association analysis methods commonly used in GWAS for common variants do not have enough power for detecting rare variants with a limited sample size. As a solution to this problem, pooling rare variants by their functions provides an efficient way for identifying susceptible genes. Rare variant typically have low frequencies of minor alleles, and the distribution of the total number of minor alleles of the rare variants can be approximated by a Poisson distribution. Based on this fact, we propose a new test method, the Poisson Approximation-based Score Test (PAST), for association analysis of rare variants. Two testing methods, namely, ePAST and mPAST, are proposed based on different strategies of pooling rare variants. Simulation results and application to the CRESCENDO cohort data show that our methods are more powerful than the existing methods. © 2016 John Wiley & Sons Ltd/University College London.
Kurzeja, R. J.; Buckley, R. L.; Werth, D. W.; Chiswell, S. R.
2018-03-01
A method is outlined and tested to detect low level nuclear or chemical sources from time series of concentration measurements. The method uses a mesoscale atmospheric model to simulate the concentration signature from a known or suspected source at a receptor which is then regressed successively against segments of the measurement series to create time series of metrics that measure the goodness of fit between the signatures and the measurement segments. The method was applied to radioxenon data from the Comprehensive Test Ban Treaty (CTBT) collection site in Ussuriysk, Russia (RN58) after the Democratic People's Republic of Korea (North Korea) underground nuclear test on February 12, 2013 near Punggye. The metrics were found to be a good screening tool to locate data segments with a strong likelihood of origin from Punggye, especially when multiplied together to a determine the joint probability. Metrics from RN58 were also used to find the probability that activity measured in February and April of 2013 originated from the Feb 12 test. A detailed analysis of an RN58 data segment from April 3/4, 2013 was also carried out for a grid of source locations around Punggye and identified Punggye as the most likely point of origin. Thus, the results support the strong possibility that radioxenon was emitted from the test site at various times in April and was detected intermittently at RN58, depending on the wind direction. The method does not locate unsuspected sources, but instead, evaluates the probability of a source at a specified location. However, it can be extended to include a set of suspected sources. Extension of the method to higher resolution data sets, arbitrary sampling, and time-varying sources is discussed along with a path to evaluate uncertainty in the calculated probabilities.
A miniaturised image based fluorescence detection system for point-of-care-testing of cocaine abuse
Walczak, Rafał; Krüger, Jan; Moynihan, Shane
2015-08-01
In this paper, we describe a miniaturised image-based fluorescence detection system and demonstrate its viability as a highly sensitive tool for point-of-care-analysis of drugs of abuse in human sweat with a focus on monitor individuals for drugs of abuse. Investigations of miniaturised and low power optoelectronic configurations and methodologies for real-time image analysis were successfully carried out. The miniaturised fluorescence detection system was validated against a reference detection system under controlled laboratory conditions by analysing spiked sweat samples in dip stick and then strip with sample pad. As a result of the validation studies, a 1 ng mL-1 limit of detection of cocaine in sweat and full agreement of test results with the reference detection system can be reported. Results of the investigations open the way towards a detection system that integrates a hand-held fluorescence reader and a wearable skinpatch, and which can collect and in situ analyse sweat for the presence of cocaine at any point for up to tenths hours.
Development of real-time PCR tests for the detection of Tenebrio molitor in food and feed.
Debode, Frédéric; Marien, Aline; Gérard, Amaury; Francis, Frédéric; Fumière, Olivier; Berben, Gilbert
2017-08-01
Insects are rich in proteins and could be an alternative source of proteins to feed animals and humans. Numerous companies have started the production of insects for feed purposes. In Europe, these processed animal proteins are not yet authorised by legislation as many questions still need to be answered concerning this 'novel food'. Authorisations will be possible when methods of authentication of the products are available. In this study we propose real-time PCR methods for the specific detection of the mealworm (Tenebriomolitor), one of the most widely used insects for food and feed production. Two PCR assays are proposed: the first based on the wingless gene and the second based on the cadherin gene. The PCR tests amplify fragments of 87 bp. These qualitative methods were tested according to several performance criteria. The specificity was tested on 34 insect species' DNA, but also on non-insect species including crustacean, mammals, birds and plants. The limit of detection was determined and was below 20 copies for the two PCR tests. The applicability of the tests was demonstrated by the analysis of real-life processed samples containing T. molitor.
Program for generating tests for the detection of failures in combinatorial logic systems
International Nuclear Information System (INIS)
Mansour, Mounir
1972-01-01
A method for generating test sequences for detecting failures in combinatorial logic systems, is described. It relies on: the splitting of these systems into elements of NOR and NAND circuits, the propagation of the failure state from the input to the output. Test sequences generation is achieved in two steps: a first one called chaining during which are investigated the propagation paths of an input state able to show off failures, a second one called consistency during which the global state of the circuit related to this input configuration is held to the wanted state so that the propagation takes place. (author) [fr
Directory of Open Access Journals (Sweden)
Sundaran S. Tinky
2015-04-01
Full Text Available Aim: The present study was undertaken to detect the presence of canine parvovirus (CPV in fecal samples of diarrheic dogs by conventional polymerase chain reaction (PCR and immunochromatographic (IC strip test and to compare the diagnostic potential of these tests. Materials and Methods: A total of 50 fecal samples collected from diarrheic dogs suspected for CPV infection were subjected to PCR using CPV-555 primer amplifying the gene coding for the VP1 protein. These samples were also tested by IC strip test using a commercial rapid Ag test kit. The results were statistically analyzed using McNemar test. Results: A total of 22 samples (44% were detected as positive by PCR, which yielded a specific amplicon of 583 bp. In IC strip test, 18 (36% samples were found to be positive. The sensitivity of the test as compared to PCR was found to be 72.22% and specificity was 92.86%. Positive predictive value and negative predictive value of IC strip test was found to be 88.89% and 81.25%, respectively. Statistical analysis of the results of PCR and IC assay using McNemar test revealed no significant difference (p>0.05. Conclusion: The IC strip test could be employed as a rapid field level diagnostic tool for the diagnosis of canine parvoviral diarrhea.
Directory of Open Access Journals (Sweden)
George eVisu-Petra
2013-03-01
Full Text Available The possibility to enhance the detection efficiency of the Concealed Information Test (CIT by increasing executive load was investigated, using an interference design. After learning and executing a mock crime scenario, subjects underwent three deception detection tests: an RT-based CIT, an RT-based CIT plus a concurrent memory task (CITMem, and an RT-based CIT plus a concurrent set-shifting task (CITShift. The concealed information effect, consisting in increased RT and lower response accuracy for probe items compared to irrelevant items, was evidenced across all three conditions. The group analyses indicated a larger difference between RTs to probe and irrelevant items in the dual-task conditions, but this difference was not translated in a significantly increased detection efficiency at an individual level. Signal detection parameters based on the comparison with a simulated innocent group showed accurate discrimination for all conditions. Overall response accuracy on the CITMem was highest and the difference between response accuracy to probes and irrelevants was smallest in this condition. Accuracy on the concurrent tasks (Mem and Shift was high, and responses on these tasks were significantly influenced by CIT stimulus type (probes vs. irrelevants. The findings are interpreted in relation to the cognitive load/dual-task interference literature, generating important insights for research on the involvement of executive functions in deceptive behavior.
Review of Literature on Probability of Detection for Magnetic Particle Nondestructive Testing
2013-01-01
a precipitation hardened martensitic stainless steel . The inspections were based on MIL-STD-1949A [51], now superseded but current at the time...inspector population involved in the tests, it is not possible to draw any further conclusions. MPT of flat 17-4PH stainless steel plates. A brief...inspection method used to detect surface-breaking cracks in high-strength steel components. A survey of the available literature on the reliability
Bolan, Barbara; Foster, Jonathan K.; Schmand, Ben; Bolan, Steve
2002-01-01
Three experiments provided validation data for an English language version of the Amsterdam Short Term Memory Test (ASTM test) developed to detect feigned memory impairment. Using a simulation design, the ASTM test compared favourably with the Test of Memory Malingering (TOMM) and appeared better
Rosen, Rachel; Amirault, Janine; Giligan, Emily; Khatwa, Umakanth; Nurko, Samuel
2014-01-01
One of the primary reasons for referral for reflux testing is to correlate reflux events with symptoms such as cough. Adult studies have suggested that symptom recording is flawed and pediatricians feel this is an even more significant problem because there may be errors in both parental and patient reports. We hypothesize that intraesophageal pressure recording (IEPR) provides an objective method to identify coughs during reflux testing in children. We recruited 20 children undergoing multichannel intraluminal impedance with pH (pH-MII) testing for the evaluation of cough. We placed simultaneous intraesophageal pressure and pH-MII catheters. Tracings were blindly scored by 2 observers without knowledge of patient/parent symptom report. After the blinded scoring, patient/parent report of symptoms was recorded. Ninety-four percent of all coughs were detected by IEPR and only 48% of all coughs were reported by patients/parents. The mean time from the IEPR cough to the patient/parent cough was 11±16 seconds. Using IEPR as the criterion standard for the detection of cough, the sensitivity of patient report for the detection of cough is 46%. Using varying symptom windows because of the increased precision of IEPR, the number of patients with a positive symptom index could be reduced from 30% to 0%, preventing children from being falsely categorized as having reflux-related lung disease. Parental and patient symptom recording in children is inadequate for making the diagnosis of reflux-related lung disease. If patients undergo pH-MII testing for reflux-related cough, IEPR should become the new standard by which to correlate reflux with cough.
Directory of Open Access Journals (Sweden)
Tuan Nur Akmalina Mat Jusoh
2017-01-01
Full Text Available The shattering rise in dengue virus infections globally has created a need for an accurate and validated rapid diagnostic test for this virus. Rapid diagnostic test (RDT and reverse transcription-polymerase chain reaction (RT-PCR diagnostic detection are useful tools for diagnosis of early dengue infection. We prospectively evaluated the diagnostic performance of nonstructural 1 (NS1 RDT and real-time RT-PCR diagnostic kits in 86 patient serum samples. Thirty-six samples were positive for dengue NS1 antigen while the remaining 50 were negative when tested with enzyme-linked immunosorbent assay (ELISA. Commercially available RDTs for NS1 detection, RTK ProDetect™, and SD Bioline showed high sensitivity of 94% and 89%, respectively, compared with ELISA. GenoAmp® Trioplex Real-Time RT-PCR and RealStar® Dengue RT-PCR tests presented a comparable kappa agreement with 0.722. The result obtained from GenoAmp® Real-Time RT-PCR Dengue test showed that 14 samples harbored dengue virus type 1 (DENV-1, 8 samples harbored DENV-2, 2 samples harbored DENV-3, and 1 sample harbored DENV-4. 1 sample had a double infection with DENV-1 and DENV-2. The NS1 RDTs and real-time RT-PCR tests were found to be a useful diagnostic for early and rapid diagnosis of acute dengue and an excellent surveillance tool in our battle against dengue.
Bakhshi, Hooman; Alavi-Moghaddam, Mostafa; Wu, Karin C; Imami, Mohammad; Banasiri, Mohammad
2012-06-01
Measuring the plasma levels of D-dimer is an accurate and easy modality to detect deep vein thrombosis (DVT) in nontraumatic settings. However, the diagnostic reliability of D-dimer assays in detecting posttraumatic DVT among patients with lower limb fracture undergoing orthopedic surgery is not validated. In this study, 141 patients with lower limb fracture admitted through the emergency department and undergoing orthopedic surgery were enrolled. Postoperative venous blood samples for D-dimer assay were taken on the 1st, 7th, and 28th postoperative days. Color Doppler sonography examination of both lower limbs was performed at the same time as a standard test. Eight out of the 141 patients (6%) had acute DVT based on Color Doppler sonography. Mean D-dimer was 2160 ng/mL in DVT positive patients and 864 in DVT negative patients. D-dimer levels greater than 1000 ng/mL were 100% sensitive and 71% specific for detecting postoperative DVT. D-dimer assay is a useful and sensitive test for detecting posttraumatic DVT.
Directory of Open Access Journals (Sweden)
Jae-Sik Jeon
2017-01-01
Full Text Available Background: Approximately 50% of the world population is infected with Helicobacter pylori, which corresponds to a high infection rate. Furthermore, the incidence of antibiotic-resistant H. pylori has increased with the recent rise in use of antibiotics for H. pylori elimination, suggesting growing treatment failures. Aim: The study was aimed to assess the use of residual samples from rapid urease test (RUT for biomolecular testing as an effective and accurate method to detect antibiotic-resistant H. pylori. Settings and Design: This study was a retrospective study performed using data obtained from medical records of previously isolated H. pylori strains. Materials and Methods: RUT was conducted for 5440 biopsy samples from individuals who underwent health examination in South Korea. Subsequently, 469 RUT residual samples were randomly selected and subjected to polymerase chain reaction (PCR to detect antibiotic-resistant H. pylori. Statistical Analysis Used: The Chi-square test was used to analyse categorical data. P < 0.05 was considered statistically significant. Results: The results showed a concordance between the results of PCR and conventional RUT in 450 of 469 samples, suggesting that the H. pylori PCR test is a time- and cost-effective detection method. Conclusions: This study demonstrated that PCR test can aid physicians to prescribe the appropriate antibiotics at the time of diagnosis, thus preventing the reduction in H. pylori eradication due to antibiotic resistance, averting progression to serious diseases and increasing the treatment success rate.
Directory of Open Access Journals (Sweden)
Shaheda Anwar
2010-01-01
Full Text Available There are no standard methods for the detection of metallo-b-lactamase (MBL production in gram negative organism in routine microbiology practice. The present study was undertaken to evaluate the screening tests like double disk synergy test (DDST and disk potentiation test (DPT using ceftazidime (CAZ and imipenem (IPM disks with chelating agents like EDTA, 2-mercaptopropionic acid (2-MPA. A total of 132 Pseudomonas and 76 Acinetobacter isolates were obtained from Bangabandhu Sheikh Mujib Medical University (BSMMU and Bangladesh Institute of Research and Rehabilitation for Diabetes, Endocrine and Metabolic Disorders (BIRDEM hospitals of Dhaka city. A total of 53 and 29 IPM resistant Pseudomonas and Acinetobacter isolates were selected. EDTA-IPM microdilution minimum inhibitory concentration (EDTA-IPM MIC method detected MBL in 44 (83% IPM resistant Pseudomonas and 19 (65.5% Acinetobacter isolates. DDST with CAZ-0.1M EDTA and CAZ-2-MPA detected MBL in 73.6% and 67.9% of IPM resistant Pseudomonas and 55.2% and 48.3% of Acinetobacter isolates respectively. The detection rate was 67.9% and 66.1% in Pseudomonas and 51.7% and 44.8% in Acinetobacter isolates by EDTA-IPM and IPM-2-MPA methods respectively. In comparison to DDST, DPT with CAZ-0.1M EDTA showed higher sensitivity (89.7% and specificity (100% for detection of MBL in Pseudomonas and Acinetobacter. The results showed that simple screening tests like DPT with 0.1M EDTA was able to detect MBL producing Pseudomonas and Acinetobacter from clinical samples with high sensitivity and specificity. Ibrahim Med. Coll. J. 2010; 4(1: 26-30
International Nuclear Information System (INIS)
Casali, P.; Bossus, A.; Carpentier, N.A.; Lambert, P.H.
1977-01-01
Bovine conglutinin was used in a solid-phase assay for the detection of immune complexes. In a first step, the tested serum sample was incubated in polypropylene tubes coated with conglutinin to allow C3-coated immune complexes to bind to solid-phase conglutinin. In a second step, the conglutinin-bound complexes were detected using an enzyme-conjugated or radiolabelled anti-immunoglobulin antibody. The conglutinin-binding (KgB) test did not suffer from the interference of DNA, heparin or endotoxins. Its limit of sensitivity for aggregated IgG was 3 μg/ml undiluted human serum. Immune complexes prepared in vitro using tetanus toxoid, or DNA, and corresponding antibodies in human sera could be detected at various antigen/antibody ratios and at antibody concentrations lower than 8 μg/ml. The KgB test allowed for the detection of immune complexes in sera from patients with systemic lupus erythematosus, rheumatoid arthritis, idiopathic vasculitis, leprosy and leukemia. These sera were also tested using the 125 I-labelled Clq-binding activity (BA) test and the KgB test simultaneously, and a significant rank order correlation was observed. In patients with leukemia, a significant correlation was observed using three tests, KgB, 125 I-labelled Clq BA and Raji-cell radioimmunoassay (RIA). Therefore, the KgB test appears as a simple and reproducible method, utilizing a very stable reagent, with a sensitivity and specificity comparable to the other tests studied and allowing for clinical application. (author)
Sequential Analysis: Hypothesis Testing and Changepoint Detection
2014-07-11
maintains the flexibility of deciding sooner than the fixed sample size procedure at the price of some lower power [13, 514]. The sequential probability... markets , detection of signals with unknown arrival time in seismology, navigation, radar and sonar signal processing, speech segmentation, and the... skimming cruise missile can yield a significant increase in the probability of raid annihilation. Furthermore, usually detection systems are
International Nuclear Information System (INIS)
Komai, Masafumi
2001-07-01
Fast reactor core anomalies can be detected in near real-time with acoustic sensors. An acoustic detection system senses an in-core anomaly immediately from the fast acoustic signals that propagate through the sodium coolant. One example of a detectable anomaly is sodium boiling due to local blockage in a sub-assembly; the slight change in background acoustic signals can be detected. A key advantage of the acoustic detector is that it can be located outside the core. The location of the anomaly in the core can be determined by correlating multiple acoustic signals. This report describes the testing and fundamental characteristics of a microphone suitable for use in the sodium coolant and examines methods to improve the system's S/N ratio. Testing in water confirmed that the in-sodium microphone has good impulse and wide band frequency responses. These tests used impulse and white noise signals that imitate acoustic signals from boiling sodium. Correlation processing of multiple microphone signals to improve S/N ratio is also described. (author)
DEFF Research Database (Denmark)
Wollenberger, Leah
/antagonistic activity with the ecdysteroid-responsive Drosophila melanogaster BII cell line 6) to draft an OECD guideline proposal for testing of chemicals based on the experimental work performed within this study In preliminary investigations with A. tonsa were studied various parameters related to processes......New and updated test methods to detect and characterise endocrine disrupting chemicals are urgently needed for the purpose of environmental risk assessment. Although endocrine disruption in invertebrates has not been studied as extensive as in vertebrates, in particular in fish, numerous reports...... of the present Ph.D. project were: 1) to develop a fully synthetic saltwater medium suitable for laboratory culturing of marine copepods including their feeding organism as well as for toxicity testing 2) to identify sensitive endpoints related to growth, development and reproduction of the pelagic calanoid...
International Nuclear Information System (INIS)
Gelston, Gariann M.
2010-01-01
For the Domestic Nuclear Detection Office's Rail Test Center (i.e., DNDO's RTC), port operation knowledge with flexible collection tools and technique are essential in both technology testing design and implementation intended for live operational settings. Increased contextual data, flexibility in procedures, and rapid availability of information are keys to addressing the challenges of optimization, validation, and analysis within live operational setting data collection. These concepts need to be integrated into technology testing designs, data collection, validation, and analysis processes. A modified data collection technique with a two phased live operation test method is proposed.
[Validity of AUDIT test for detection of disorders related with alcohol consumption in women].
Pérula-de Torres, Luis Angel; Fernández-García, José Angel; Arias-Vega, Raquel; Muriel-Palomino, María; Márquez-Rebollo, Encarnación; Ruiz-Moral, Roger
2005-11-26
Early detection of patients with alcohol problems is important in clinical practice. The AUDIT (Alcohol Use Disorders Identification Test) questionnaire is a valid tool for this aim, especially in the male population. The objective of this study was to validate how useful is this questionnaire in females patients and to assess their test cut-off point for the diagnosis of alcohol problems in women. 414 woman were recruited in 2 health center and specialized center for addiction treatment. The AUDIT test and a semistructured interview (SCAN as gold standard) were performed to all patients. Internal consistency and criteria validity was assessed. Cronbach alpha was 0.93 (95% confidence interval [CI], 0.921-0.941). When the DSM-IV was taken as reference the most useful cut-off point was 6 points, with 89.6% (95% CI, 76.11-96.02) sensitivity and 95.07% (95% CI, 92.18-96.97) specificity. When CIE-10 was taken as reference the sensitivity was 89.58% (95% CI, 76.56-96.10) and the specificity was 95.33% (95% CI, 92.48-97.17). AUDIT is a questionnaire with good psychometrics properties and is valid for detecting dependence and risk alcohol consumption in women.
On the importance of developing a new generation of breath tests for Helicobacter pylori detection.
Kushch, Ievgeniia; Korenev, Nikolai; Kamarchuk, Lyudmila; Pospelov, Alexander; Kravchenko, Andrey; Bajenov, Leonid; Kabulov, Mels; Amann, Anton; Kamarchuk, Gennadii
2015-12-15
State-of-the-art methods for non-invasive detection of the Helicobacter pylori (H. pylori) infection have been considered. A reported global tendency towards a non-decreasing prevalence of H. pylori worldwide could be co-influenced by the functional limitations of urea breath tests (UBTs), currently preferred for the non-invasive recognition of H. pylori in a clinical setting. Namely, the UBTs can demonstrate false-positive or false-negative results. Within this context, limitations of conventional clinically exploited H. pylori tests have been discussed to justify the existing need for the development of a new generation of breath tests for the detection of H. pylori and the differentiation of pathogenic and non-pathogenic strains of the bacterium. This paper presents the results of a pilot clinical study aimed at evaluating the development and diagnostic potential of a new method based on the detection of the non-urease products of H. pylori vital activity in exhaled gas. The characteristics of breath of adolescents with H. pylori-positive and H. pylori-negative functional dyspepsia, together with a consideration of the cytotoxin-associated gene A (CagA) status of H. pylori-positive subjects, have been determined for the first time using innovative point-contact nanosensor devices based on salts of the organic conductor tetracyanoquinodimethane (TCNQ). The clinical and diagnostic relevance of the response curves of the point-contact sensors was assessed. It was found that the recovery time of the point-contact sensors has a diagnostic value for differentiation of the H. pylori-associated peptic ulcer disease. The diagnostically significant elongation of the recovery time was even more pronounced in patients infected with CagA-positive H. pylori strains compared to the CagA-negative patients. Taking into account the operation of the point-contact sensors in the real-time mode, the obtained results are essential prerequisites for the development of a fast and
Gish, R G; Gutierrez, J A; Navarro-Cazarez, N; Giang, K; Adler, D; Tran, B; Locarnini, S; Hammond, R; Bowden, S
2014-12-01
Early identification of chronic hepatitis B is important for optimal disease management and prevention of transmission. Cost and lack of access to commercial hepatitis B surface antigen (HBsAg) immunoassays can compromise the effectiveness of HBV screening in resource-limited settings and among marginalized populations. High-quality point-of-care (POC) testing may improve HBV diagnosis in these situations. Currently available POC HBsAg assays are often limited in sensitivity. We evaluated the NanoSign(®) HBs POC chromatographic immunoassay for its ability to detect HBsAg of different genotypes and with substitutions in the 'a' determinant. Thirty-seven serum samples from patients with HBV infection, covering HBV genotypes A-G, were assessed for HBsAg titre with the Roche Elecsys HBsAg II quantification assay and with the POC assay. The POC assay reliably detected HBsAg at a concentration of at least 50 IU/mL for all genotypes, and at lower concentrations for some genotypes. Eight samples with substitutions in the HBV 'a' determinant were reliably detected after a 1/100 dilution. The POC strips were used to screen serum samples from 297 individuals at risk for HBV in local clinical settings (health fairs and outreach events) in parallel with commercial laboratory HBsAg testing (Quest Diagnostics EIA). POC testing was 73.7% sensitive and 97.8% specific for detection of HBsAg. Although the POC test demonstrated high sensitivity over a range of genotypes, false negatives were frequent in a clinical setting. Nevertheless, the POC assay offers advantages for testing in both developed and resource-limited countries due to its low cost (0.50$) and immediately available results. © 2014 John Wiley & Sons Ltd.
Gunderson, Bruce D; Gillberg, Jeffrey M; Wood, Mark A; Vijayaraman, Pugazhendhi; Shepard, Richard K; Ellenbogen, Kenneth A
2006-02-01
Implantable cardioverter-defibrillator (ICD) lead failures often present as inappropriate shock therapy. An algorithm that can reliably discriminate between ventricular tachyarrhythmias and noise due to lead failure may prevent patient discomfort and anxiety and avoid device-induced proarrhythmia by preventing inappropriate ICD shocks. The goal of this analysis was to test an ICD tachycardia detection algorithm that differentiates noise due to lead failure from ventricular tachyarrhythmias. We tested an algorithm that uses a measure of the ventricular intracardiac electrogram baseline to discriminate the sinus rhythm isoelectric line from the right ventricular coil-can (i.e., far-field) electrogram during oversensing of noise caused by a lead failure. The baseline measure was defined as the product of the sum (mV) and standard deviation (mV) of the voltage samples for a 188-ms window centered on each sensed electrogram. If the minimum baseline measure of the last 12 beats was algorithm to detect lead failures. The minimum baseline measure for the 24 lead failure episodes (0.28 +/- 0.34 mV-mV) was smaller than the 135 ventricular tachycardia (40.8 +/- 43.0 mV-mV, P <.0001) and 55 ventricular fibrillation episodes (19.1 +/- 22.8 mV-mV, P <.05). A minimum baseline <0.35 mV-mV threshold had a sensitivity of 83% (20/24) with a 100% (190/190) specificity. A baseline measure of the far-field electrogram had a high sensitivity and specificity to detect lead failure noise compared with ventricular tachycardia or fibrillation.
International Nuclear Information System (INIS)
Sigit Asmara Santa
2006-01-01
The engineering sensitivity improvement of Helium mass spectrometer leak detection using global hard vacuum test configuration has been done. The purpose of this work is to enhance the sensitivity of the current leak detection of pressurized method (sniffer method) with the sensitivity of 10 -3 ∼ 10 -5 std cm 3 /s, to the global hard vacuum test configuration method which can be achieved of up to 10 -8 std cm 3 /s. The goal of this research and development is to obtain a Helium leak test configuration which is suitable and can be used as routine bases in the quality control tests of FPM capsule and AgInCd safety control rod products. The result is an additional instrumented vacuum tube connected with conventional Helium mass spectrometer. The pressure and temperature of the test object during the leak measurement are simulated by means of a 4.1 kW capacity heater and Helium injection to test object, respectively. The addition of auxiliary mechanical vacuum pump of 2.4 l/s pumping speed which is directly connected to the vacuum tube, will reduce 86 % of evacuation time. The reduction of the measured sensitivity due to the auxiliary mechanical vacuum pump can be overcome by shutting off the pump soon after Helium mass spectrometer reaches its operating pressure condition. (author)
Integrated sample-to-detection chip for nucleic acid test assays.
Prakash, R; Pabbaraju, K; Wong, S; Tellier, R; Kaler, K V I S
2016-06-01
Nucleic acid based diagnostic techniques are routinely used for the detection of infectious agents. Most of these assays rely on nucleic acid extraction platforms for the extraction and purification of nucleic acids and a separate real-time PCR platform for quantitative nucleic acid amplification tests (NATs). Several microfluidic lab on chip (LOC) technologies have been developed, where mechanical and chemical methods are used for the extraction and purification of nucleic acids. Microfluidic technologies have also been effectively utilized for chip based real-time PCR assays. However, there are few examples of microfluidic systems which have successfully integrated these two key processes. In this study, we have implemented an electro-actuation based LOC micro-device that leverages multi-frequency actuation of samples and reagents droplets for chip based nucleic acid extraction and real-time, reverse transcription (RT) PCR (qRT-PCR) amplification from clinical samples. Our prototype micro-device combines chemical lysis with electric field assisted isolation of nucleic acid in a four channel parallel processing scheme. Furthermore, a four channel parallel qRT-PCR amplification and detection assay is integrated to deliver the sample-to-detection NAT chip. The NAT chip combines dielectrophoresis and electrostatic/electrowetting actuation methods with resistive micro-heaters and temperature sensors to perform chip based integrated NATs. The two chip modules have been validated using different panels of clinical samples and their performance compared with standard platforms. This study has established that our integrated NAT chip system has a sensitivity and specificity comparable to that of the standard platforms while providing up to 10 fold reduction in sample/reagent volumes.
Damage detection in concrete precast slabs: a quick assessment through modal tests
Directory of Open Access Journals (Sweden)
Leal Pimentel Roberto
2015-01-01
Full Text Available The use of modal tests for detecting damage in reinforced concrete precast slabs is evaluated. A set of eight slabs were tested, each belonging to flats constructed for residential use. Two groups of slabs were identified and, in each group, both cracked and uncracked slabs were found. This made it possible to compare the responses of the slabs when subjected to modal tests. The tests were carried out employing an instrumented hammer and heel drops as excitation sources. Responses were measured using an accelerometer. The lowest natural frequencies of the slabs could be identified and after filtering the results, plots indicating the variation of the lowest natural frequency versus the number of cycles of free decay were obtained for each slab. Such a plot is of more general use than the value of the natural frequency by itself, as it does not depend on slab configuration. It was observed that the cracked slabs presented a similar pattern of variation of the natural frequencies throughout the decay, being distinctive from the pattern observed for their uncracked counterparts. This provided evidence that a quick assessment of the structural condition of such slabs through the use of the tests were feasible.
Parametric Roll Resonance Detection using Phase Correlation and Log-likelihood Testing Techniques
DEFF Research Database (Denmark)
Galeazzi, Roberto; Blanke, Mogens; Poulsen, Niels Kjølstad
2009-01-01
generation warning system the purpose of which is to provide the master with an onboard system able to trigger an alarm when parametric roll is likely to happen within the immediate future. A detection scheme is introduced, which is able to issue a warning within five roll periods after a resonant motion......Real-time detection of parametric roll is still an open issue that is gathering an increasing attention. A first generation warning systems, based on guidelines and polar diagrams, showed their potential to face issues like long-term prediction and risk assessment. This paper presents a second...... started. After having determined statistical properties of the signals at hand, a detector based on the generalised log-likelihood ratio test (GLRT) is designed to look for variation in signal power. The ability of the detector to trigger alarms when parametric roll is going to onset is evaluated on two...
Sensitive technique for detecting outer defect on tube with remote field eddy current testing
International Nuclear Information System (INIS)
Kobayashi, Noriyasu; Nagai, Satoshi; Ochiai, Makoto; Jimbo, Noboru; Komai, Masafumi
2008-01-01
In the remote field eddy current testing, we proposed the method of enhancing the magnetic flux density in the vicinity of an exciter coil by controlling the magnetic flux direction for increasing the sensitivity of detecting outer defects on a tube and used the flux guide made of a magnetic material for the method. The optimum structural shape of the flux guide was designed by the magnetic field analysis. On the experiment with the application of the flux guide, the magnetic flux density increased by 59% and the artificial defect detection signal became clear. We confirmed the proposed method was effective in a high sensitivity. (author)
Klaus, Christine; Beer, Martin; Saier, Regine; Schubert, Harald; Bischoff, Sabine; Süss, Jochen
2011-01-01
Tick-borne encephalitis (TBE) in animals is not well understood yet. TBE virus (TBEV) serology in several host species could be valuable for epidemiological analyses in the field as well as for the detection of clinical cases. However, performance and suitability of the available test systems are not well assessed. Therefore, we evaluated two commercial TBEV-ELISA kits in a pilot study and compared them for their suitability in veterinary applications. For this purpose, we tested 163 field collected goat sera and evaluated the results by serum neutralization test (SNT) as "gold standard". Twenty-eight SNT positive sera (17.2%) were detected. The best suited ELISA kit was used for determination of a species-specific cutoff for horses, cattle, sheep, goats, pigs, mice, dogs, rabbits and monkeys with defined sera from animals without known or with improbable contact to TBEV. The level of non-specific ELISA results does not only differ between animal species but may also be influenced by the age of the tested animals. The number of sera which tested false positive by ELISA was higher in older than in young sheep. In order to obtain defined polyclonal sera as references, two dogs, cattle, goats, sheep, rabbits and pigs each, as well as one horse and 90 mice were immunized four times with a commercially available TBEV vaccine. In conclusion, our results demonstrated that commercial TBEV-ELISA kits are suitable for application in veterinary medicine for both, verification of clinical TBE cases and epidemiological screening. However, positive ELISA results should be verified by SNT. Only a very low number of false negative ELISA-results were found.
A combination test for detection of gene-environment interaction in cohort studies.
Coombes, Brandon; Basu, Saonli; McGue, Matt
2017-07-01
Identifying gene-environment (G-E) interactions can contribute to a better understanding of disease etiology, which may help researchers develop disease prevention strategies and interventions. One big criticism of studying G-E interaction is the lack of power due to sample size. Studies often restrict the interaction search to the top few hundred hits from a genome-wide association study or focus on potential candidate genes. In this paper, we test interactions between a candidate gene and an environmental factor to improve power by analyzing multiple variants within a gene. We extend recently developed score statistic based genetic association testing approaches to the G-E interaction testing problem. We also propose tests for interaction using gene-based summary measures that pool variants together. Although it has recently been shown that these summary measures can be biased and may lead to inflated type I error, we show that under several realistic scenarios, we can still provide valid tests of interaction. These tests use significantly less degrees of freedom and thus can have much higher power to detect interaction. Additionally, we demonstrate that the iSeq-aSum-min test, which combines a gene-based summary measure test, iSeq-aSum-G, and an interaction-based summary measure test, iSeq-aSum-I, provides a powerful alternative to test G-E interaction. We demonstrate the performance of these approaches using simulation studies and illustrate their performance to study interaction between the SNPs in several candidate genes and family climate environment on alcohol consumption using the Minnesota Center for Twin and Family Research dataset. © 2017 WILEY PERIODICALS, INC.
A New Generalizable Test for Detection of Mutations Affecting Tn10 Transposition
Huisman, Olivier; Kleckner, Nancy
1987-01-01
We describe here a new rapid screen that allows easy detection of transposon or host mutations that affect Tn10 transposition in Escherichia coli. This test involves a new Tn10 derivative called the "mini-lacZ-kanR fusion hopper" or mini-Tn10-LK for short. This element does not direct expression of β-galactosidase when present at its original starting location on a suitably engineered plasmid or phage genome because it lacks appropriate transcription and translation start signals. However, t...
López, Iria Cebreiros; Aroca, Florentina Guzmán; Bernal, Maria Dolores Frutos; Mompeán, Juan Antonio Luján; Bernal, Águeda Bas; Martínez, Antonio Miguel Hernández; Barba, Enrique Martínez; Velasco, Jose Antonio Noguera; Paricio, Pascual Parilla
2017-09-01
Morbid obese patients have a high rate of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). NASH is related to the progression and poor evolution of chronic hepatopathy in NAFLD, so that its detection makes it possible to identify the subjects who are most at risk in order to prioritize treatment. The ELF test (Enhanced Liver Fibrosis test; Siemens Diagnostics, NY, USA) has been assessed for its capacity to detect fibrosis in patients with NAFLD, but its capacity for diagnosing NASH has not been checked. Our objective is to determine the utility of the ELF test for detecting NASH in morbid obese patients with suspected NAFLD. ELF values were determined in a cohort of obese patients who underwent bariatric surgery with suspected NAFLD. Liver biopsy was used as the reference standard. The values of ELF were significantly higher in patients with NASH (p = 0.002) and in those who presented with metabolic syndrome (p = 0.047). An ELF cut-off point of 8.72 allows the detection of patients with NASH with a sensitivity of 71.4% and a specificity of 74.1% (AUC = 0.742, p = 0.002). The ELF test is efficient for the identification of obese patients with NAFLD and early signs of steatohepatitis and fibrosis.
Directory of Open Access Journals (Sweden)
Vlademir Vicente Cantarelli
Full Text Available Detection of AmpC beta-lactamase production by enterobacteria has been problematic. Contrary to ESBLs, no specific guidelines are available for detection and confirmation of AmpC production by clinical relevant microorganisms. Moreover, some bacterial species may produce inducible AmpC beta-lactamases that can be easily overlooked by routine susceptibility tests. We reported here a new test based on the strong inducible effect of imipenem on AmpC genes and the consequent antagonism with ceftazidime. This test is very simple and proved to be helpful in detecting AmpC-inducible enzymes among several species of clinical isolates.
Arm exercise-thallium imaging testing for the detection of coronary artery disease
International Nuclear Information System (INIS)
Balady, G.J.; Weiner, D.A.; Rothendler, J.A.; Ryan, T.J.
1987-01-01
Patients with lower limb impairment are often unable to undergo a standard bicycle or treadmill test for the evaluation of coronary artery disease. To establish an alternative method of testing, 50 subjects (aged 56 +/- 10 years) performed arm ergometry testing in conjunction with myocardial thallium scintigraphy. All underwent coronary angiography; significant coronary artery disease (greater than or equal to 70% stenosis) in at least one vessel was present in 41 (82%) of the 50 patients. Thallium scintigraphy was found to have an 83% sensitivity and 78% specificity for detecting coronary disease, compared with a sensitivity and specificity of 54% (p less than 0.01) and 67% (p = NS), respectively, for exercise electrocardiography. In the subgroup of 23 patients who had no prior myocardial infarction or left bundle branch block and were not taking digitalis, thallium scintigraphy had a sensitivity of 80% versus 50% for exercise electrocardiography. Scintigraphy yielded a sensitivity of 84, 74 and 90% for one, two and three vessel disease, respectively. Noninvasive arm ergometry exercise-thallium imaging testing appears to be reliable and useful and should be considered in the evaluation of coronary artery disease in patients with lower limb impairment
Directory of Open Access Journals (Sweden)
Yue Zhang
2018-02-01
Full Text Available A quantitative lateral-flow immunoassay using gold nanoparticles (AuNPs conjugated with a monoclonal antibody (MAb against saikosaponin d (SSd was developed for the analysis of SSd. The AuNPs were prepared in our laboratory. The AuNPs were polyhedral, with an average diameter of approximately 18 nm. We used the conjugation between AuNPs and MAbs against SSd to prepare immunochromatographic strips (ICSs. For the quantitative experiment, the strips with the test results were scanned using a membrane strip reader, and a detection curve (regression equation, y = −0.113ln(x + 1.5451, R2 = 0.983, representing the averages of the scanned data, was obtained. This curve was linear from 96 ng/mL to 150 μg/mL, and the IC50 value was 10.39 μg/mL. In this study, we bring the concept of POCT (point-of-care testing to the measurement of TCM compounds, and this is the first report of quantitative detection of SSd by an ICS.
Handali, Sukwan; Klarman, Molly; Gaspard, Amanda N; Dong, X Fan; Laborde, Ronald; Noh, John; Lee, Yeuk-Mui; Rodriguez, Silvia; Gonzalez, Armando E; Garcia, Hector H; Gilman, Robert H; Tsang, Victor C W; Wilkins, Patricia P
2010-04-01
Taeniasis/cysticercosis caused by Taenia solium is a frequent parasitic infection of the human brain in most of the world. Rapid and simple screening tools to identify taeniasis and cysticercosis cases are needed for control programs, mostly to identify tapeworm carriers which are the source of infection and need to be treated, or as tools for point-of-care case detection or confirmation. These screening assays should be affordable, reliable, rapid, and easy to perform. Immunochromatographic tests meet these criteria. To demonstrate proof of principle, we developed and evaluated two magnetic immunochromatographic tests (MICTs) for detection of human Taenia solium taeniasis antibodies (ES33-MICT) and neurocysticercosis antibodies (T24-MICT). These assays detected stage-specific antibodies by using two recombinant proteins, rES33 for detection of taeniasis antibodies and rT24H for detection of cysticercosis antibodies. The sensitivity and specificity of the ES33-MICT to detect taeniasis infections were 94.5% and 96%, respectively, and those of the T24-MICT to detect cases of human cysticercosis with two or more viable brain cysts were 93.9% and 98.9%, respectively. These data provide proof of principle that the ES33- and T24-MICTs provide rapid and suitable methods to identify individuals with taeniasis and cysticercosis.
Handali, Sukwan; Klarman, Molly; Gaspard, Amanda N.; Dong, X. Fan; LaBorde, Ronald; Noh, John; Lee, Yeuk-Mui; Rodriguez, Silvia; Gonzalez, Armando E.; Garcia, Hector H.; Gilman, Robert H.; Tsang, Victor C. W.; Wilkins, Patricia P.
2010-01-01
Taeniasis/cysticercosis caused by Taenia solium is a frequent parasitic infection of the human brain in most of the world. Rapid and simple screening tools to identify taeniasis and cysticercosis cases are needed for control programs, mostly to identify tapeworm carriers which are the source of infection and need to be treated, or as tools for point-of-care case detection or confirmation. These screening assays should be affordable, reliable, rapid, and easy to perform. Immunochromatographic tests meet these criteria. To demonstrate proof of principle, we developed and evaluated two magnetic immunochromatographic tests (MICTs) for detection of human Taenia solium taeniasis antibodies (ES33-MICT) and neurocysticercosis antibodies (T24-MICT). These assays detected stage-specific antibodies by using two recombinant proteins, rES33 for detection of taeniasis antibodies and rT24H for detection of cysticercosis antibodies. The sensitivity and specificity of the ES33-MICT to detect taeniasis infections were 94.5% and 96%, respectively, and those of the T24-MICT to detect cases of human cysticercosis with two or more viable brain cysts were 93.9% and 98.9%, respectively. These data provide proof of principle that the ES33- and T24-MICTs provide rapid and suitable methods to identify individuals with taeniasis and cysticercosis. PMID:20181766
Bolan, B.; Foster, J.K.; Schmand, B.; Bolan, S.
2002-01-01
Three experiments provided validation data for an English language version of the Amsterdam Short Term Memory Test (ASTM test) developed to detect feigned memory impairment. In all 3 experiments a total of 91 Ss (aged 17-66 yrs) participated. Using a simulation design, the ASTM test compared
Kuan, Pei Fen; Chiang, Derek Y
2012-09-01
DNA methylation has emerged as an important hallmark of epigenetics. Numerous platforms including tiling arrays and next generation sequencing, and experimental protocols are available for profiling DNA methylation. Similar to other tiling array data, DNA methylation data shares the characteristics of inherent correlation structure among nearby probes. However, unlike gene expression or protein DNA binding data, the varying CpG density which gives rise to CpG island, shore and shelf definition provides exogenous information in detecting differential methylation. This article aims to introduce a robust testing and probe ranking procedure based on a nonhomogeneous hidden Markov model that incorporates the above-mentioned features for detecting differential methylation. We revisit the seminal work of Sun and Cai (2009, Journal of the Royal Statistical Society: Series B (Statistical Methodology)71, 393-424) and propose modeling the nonnull using a nonparametric symmetric distribution in two-sided hypothesis testing. We show that this model improves probe ranking and is robust to model misspecification based on extensive simulation studies. We further illustrate that our proposed framework achieves good operating characteristics as compared to commonly used methods in real DNA methylation data that aims to detect differential methylation sites. © 2012, The International Biometric Society.
Directory of Open Access Journals (Sweden)
Alex Willyandre
2013-05-01
Full Text Available Transmission of HIV-1 infection by individuals in window period who are tested negative in conventional HIV-1 detection would pose the community with serious problems. Several diagnostic tools require specific labora-tory equipment, perfect timing of diagnosis, antibody to HIV-1, and invasive technique to get sample for examination, until high amount of time to process the sample as well as accessibility of remote areas. Many attempts have been made to solve those problems to come to a new detection technique. This review aims to give information about the current development technique for detection of HIV infection. Microfluidic Chip-based Nucleic Acid Testing is currently introduced for detection of HIV-1 infection. This review also cover the possible usage of gingival crevicular fluid as sample specimen that could be taken noninvasively from the individual.DOI: 10.14693/jdi.v18i2.63
A Non-Parametric Surrogate-based Test of Significance for T-Wave Alternans Detection
Nemati, Shamim; Abdala, Omar; Bazán, Violeta; Yim-Yeh, Susie; Malhotra, Atul; Clifford, Gari
2010-01-01
We present a non-parametric adaptive surrogate test that allows for the differentiation of statistically significant T-Wave Alternans (TWA) from alternating patterns that can be solely explained by the statistics of noise. The proposed test is based on estimating the distribution of noise induced alternating patterns in a beat sequence from a set of surrogate data derived from repeated reshuffling of the original beat sequence. Thus, in assessing the significance of the observed alternating patterns in the data no assumptions are made about the underlying noise distribution. In addition, since the distribution of noise-induced alternans magnitudes is calculated separately for each sequence of beats within the analysis window, the method is robust to data non-stationarities in both noise and TWA. The proposed surrogate method for rejecting noise was compared to the standard noise rejection methods used with the Spectral Method (SM) and the Modified Moving Average (MMA) techniques. Using a previously described realistic multi-lead model of TWA, and real physiological noise, we demonstrate the proposed approach reduces false TWA detections, while maintaining a lower missed TWA detection compared with all the other methods tested. A simple averaging-based TWA estimation algorithm was coupled with the surrogate significance testing and was evaluated on three public databases; the Normal Sinus Rhythm Database (NRSDB), the Chronic Heart Failure Database (CHFDB) and the Sudden Cardiac Death Database (SCDDB). Differences in TWA amplitudes between each database were evaluated at matched heart rate (HR) intervals from 40 to 120 beats per minute (BPM). Using the two-sample Kolmogorov-Smirnov test, we found that significant differences in TWA levels exist between each patient group at all decades of heart rates. The most marked difference was generally found at higher heart rates, and the new technique resulted in a larger margin of separability between patient populations than
Directory of Open Access Journals (Sweden)
Raymond SW Tsang
2015-01-01
Full Text Available Treponema pallidum subsp. pallidum and/or its nucleic acid can be detected by various methods such as microscopy, rabbit infectivity test or polymerase chain reaction (PCR tests. The rabbit infectivity test for T. pallidum, although very sensitive, has been discontinued from most laboratories due to ethical issues related to the need for animal inoculation with live T. pallidum, the technically demanding procedure and long turnaround time for results, thus making it impractical for routine diagnostic use. Dark-field and phase-contrast microscopy are still useful at clinic- or hospital-based laboratories for near-bedside detection of T. pallidum in genital, skin or mucous lesions although their availability is decreasing. The lack of reliable and specific anti-T. pallidum antibodies and its inferior sensitivity to PCR may explain why the direct fluorescent antibody test for T. pallidum is not widely available for clinical use. Immunohistochemical staining for T. pallidum also depends on the availability of specific antibodies, and the method is only applicable for histopathological examination of biopsy and autopsy specimens necessitating an invasive specimen collection approach. With recent advances in molecular diagnostics, PCR is considered to be the most reliable, versatile and practical for laboratories to implement. In addition to being an objective and sensitive test for direct detection of Treponema pallidum subsp. pallidum DNA in skin and mucous membrane lesions, the resulting PCR amplicons from selected gene targets can be further characterized for antimicrobial (macrolide susceptibility testing, strain typing and identification of T. pallidum subspecies.
International Nuclear Information System (INIS)
Mainet Gonzalez, Damian; Palenzuela Gardon, Daniel O; Aguilar Rubido; Julio C
2009-01-01
The disappearance of the e antigen and the appearance of anti-e antigen antibodies are two biomarkers that indicate favorable prognosis in Hepatitis B. In this study the Advanced QualityTM immunochromatographic test for detecting those biomarkers was compared to the Vidas semi-quantitative ELISA test. Our hypothesis was that it is possible to use these biomarkers measured in a rapid and simple Advanced QualityTM immunochromatographic test for evaluating the therapeutic response in clinical trials with chronic hepatitis B patients. The two methods were done following the manufacturer's instructions. The sera were taken from 69 patients with chronic hepatitis B of the clinical trial of the CIGB 440 therapeutic candidate. The immunochromatographic test and ELISA for detecting e antigen and anti-e antigen antibodies presented from substantial to almost perfect agreement in the evaluation of the sera of chronic Hepatitis B patients in a clinical trial. The immunochromatographic test for detecting e antigen had a low positive average agreement and a high negative average agreement compared to the ELISA. Nevertheless, the immunochromatographic test for detecting anti-e antigen antibodies had a high negative and positive average agreement in comparison to the ELISA. The immunochromagraphic test for the e antigen had a lower positive average agreement compared to the ELISA and some patients infected with Hepatitis B virus could not be detected by the former assay. The immunochromatographic test for anti-e antigen antibodies showed a similar performance to that of ELISA and could therefore be used in clinical trials for chronic Hepatitis B in health institutions without the need of a highly qualified lab technician. (author)
Characteristics of adenomas detected by fecal immunochemical test in colorectal cancer screening.
Cubiella, Joaquín; Castro, Inés; Hernandez, Vicent; González-Mao, Carmen; Rivera, Concepción; Iglesias, Felipe; Cid, Lucía; Soto, Santiago; de-Castro, Luisa; Vega, Pablo; Hermo, Jose Antonio; Macenlle, Ramiro; Martínez, Alfonso; Martínez-Ares, David; Estevez, Pamela; Cid, Estela; Herreros-Villanueva, Marta; Portillo, Isabel; Bujanda, Luis; Fernández-Seara, Javier
2014-09-01
Fecal immunochemical test (FIT) diagnostic accuracy for colorectal adenoma detection in colorectal cancer screening is limited. We analyzed 474 asymptomatic subjects with adenomas detected on colonoscopy in two blinded diagnostic tests studies designed to assess FIT diagnostic accuracy. We determined the characteristics of adenomas (number, size, histology, morphology, and location) and the risk of metachronous lesions (according to European guidelines). Finally, we performed a logistic regression to identify those variables independently associated with a positive result. Advanced adenomas were found in 145 patients (75.6% distal and 24.3% only proximal to splenic flexure). Patients were classified as low (59.5%), intermediate (30.2%), and high risk (10.3%) according to European guidelines. At a 100-ng/mL threshold, FIT was positive in 61 patients (12.8%). Patients with advanced adenomas [odds ratio (OR), 8.8; 95% confidence interval (CI), 4.76-16.25], distal advanced adenomas (OR, 6.7; 95% CI, 1.9-8.8), high risk (OR, 20.1; 95% CI, 8.8-45.8), or intermediate risk lesions (OR, 6; 95% CI, 2.9-12.4) had more probabilities to have a positive test. The characteristics of adenomas independently associated were number of adenomas (OR, 1.22; 95% CI, 1.04-1.42), distal flat adenomas (OR, 0.44; 95% CI, 0.21-0.96), pedunculated adenomas (OR, 2.28; 95% CI, 1.48-3.5), and maximum size of distal adenomas (mm; OR, 1.24; 95% CI, 1.16-1.32). European guidelines classification and adenoma location correlates with the likelihood of a positive FIT result. This information allows us to understand the FIT impact in colorectal cancer prevention. Likewise, it should be taken into account in the development of new colorectal adenomas biomarkers. ©2014 American Association for Cancer Research.
Directory of Open Access Journals (Sweden)
M Fukuda
2009-06-01
Full Text Available Recent progress in cytogenetic and biochemical mutator assay technologies has enabled us to detect single gene alterations and gross chromosomal rearrangements, and it became clear that all cancer cells are genetically unstable. In order to detect the genome-wide instability of cancer cells, a new simple method, the DNA-instability test, was developed. The methods to detect genomic instability so far reported have only demonstrated the presence of qualitative and quantitative alterations in certain specific genomic loci. In contrast to these commonly used methods to reveal the genomic instability at certain specific DNA regions, the newly introduced DNA-instability test revealed the presence of physical DNA-instability in the entire DNA molecule of a cancer cell nucleus as revealed by increased liability to denature upon HCl hydrolysis or formamide exposure. When this test was applied to borderline malignancies, cancer clones were detected in all cases at an early-stage of cancer progression. We proposed a new concept of “procancer” clones to define those cancer clones with “functional atypia” showing positivities for various cancer markers, as well as DNA-instability testing, but showing no remarkable ordinary “morphological atypia” which is commonly used as the basis of histopathological diagnosis of malignancy.
Dyson, Judith; Cowdell, Fiona
2014-12-01
To develop and psychometrically test the Motivation and Self-Efficacy in Early Detection of Skin Lesions Index. Skin cancer is the most frequently diagnosed cancer worldwide. The primary strategy used to prevent skin cancer is promotion of sun avoidance and the use of sun protection. However, despite costly and extensive campaigns, cases of skin cancer continue to increase. If found and treated early, skin cancer is curable. Early detection is, therefore, very important. The study was conducted in 2013. Instrument Development. A literature review and a survey identified barriers (factors that hinder) and levers (factors that help) to skin self-examination. These were categorized according to a the Theoretical Domains Framework and this formed the basis of an instrument, which was tested for validity and reliability using confirmatory factor analysis and Cronbach's alpha respectively. A five-factor 20-item instrument was used that tested well for reliability and construct validity. Test-retest reliability was good for all items and domains. The five factors were: (i) Outcome expectancies; (ii) Intention; (iii) Self-efficacy; (iv) Social influences; (v) Memory. The Motivation and Self-Efficacy in Early Detection of Skin Lesions Index provides a reliable and valid method of assessing barriers and levers to skin self-examination. The next step is to design a theory-based intervention that can be tailored according to individual determinants to behaviour change identified by this instrument. © 2014 John Wiley & Sons Ltd.
Huo, Ya-Yun; Li, Gui-Fen; Qiu, Yan-Hong; Li, Wei-Min; Zhang, Yong-Jiang
2017-11-23
Prunus necrotic ringspot virus (PNRSV) is one of the most devastating viruses to Prunus spp. In this study, we developed a diagnostic system RT-CPA-NATSC, wherein reverse transcription-cross-priming amplification (RT-CPA) is coupled with nucleic acid test strip cassette (NATSC), a vertical flow (VF) visualization, for PNRSV detection. The RT-CPA-NATSC assay targets the encoding gene of the PNRSV coat protein with a limit of detection of 72 copies per reaction and no cross-reaction with the known Prunus pathogenic viruses and viroids, demonstrating high sensitivity and specificity. The reaction is performed on 60 °C and can be completed less than 90 min with the prepared template RNA. Field sample test confirmed the reliability of RT-CPA-NATSC, indicating the potential application of this simple and rapid detection method in routine test of PNRSV.
Martin-Hernandez, C.; Munoz, M.; Daury, C.; Weymuth, H.; Kemmers-Voncken, A.; Corbation, V.; Toribo, T.; Bremer, M.G.E.G.
2009-01-01
An immunochromatographic lateral-flow test dipstick test was developed for the fast detection of bovine rennet whey in liquid milk and milk powder. The test is based on the binding of casein glycomacropeptide (cGMP) by two specific anti-bovine ¿-casein monoclonal antibodies and has a visual
D’Antono, Bianca; Dupuis, Gilles; Fortin, Christophe; Arsenault, André; Burelle, Denis
2006-01-01
BACKGROUND AND OBJECTIVES To examine the capacity of angina and related symptoms experienced during exercise-stress testing to detect the presence of ischemia, controlling for other clinical factors. METHOD The authors undertook a prospective study of 482 women and 425 men (mean age 58 years) undergoing exercise stress testing with myocardial perfusion imaging. One hundred forty-six women and 127 men reported chest pain, and of these, 25% of women and 66% of men had myocardial perfusion imaging evidence of ischemia during testing. The present article focuses on patients with chest pain during testing. MAIN OUTCOME MEASURES Outcome measures included chest pain localization, extension, intensity and quality, as well as the presence of various nonpain-related symptoms. Backward logistical regression analyses were performed separately on men and women who had experienced chest pain during testing. RESULTS Men who described their chest pain as ‘heavy’ were 4.6 times more likely to experience ischemia during testing (P=0.039) compared with other men, but this pain descriptor only slightly improved accuracy of prediction beyond that provided by control variables. In women, several symptoms added to the sensitivity of the prediction, such as a numb feeling in the face or neck region (OR 4.5; P=0.048), a numb feeling in the chest area (OR 14.6; P=0.003), muscle tension (OR 5.2; P=0.013), and chest pain that was described as hot or burning (OR 4.3; P=0.014). CONCLUSIONS A more refined evaluation of symptoms experienced during testing was particularly helpful in improving detection of ischemia in women, but not in men. Attention to these symptoms may favour timely diagnosis of myocardial perfusion defects in women. PMID:16639477
Microbial changes in patients with acute periodontal abscess after treatment detected by PadoTest.
Eguchi, T; Koshy, G; Umeda, M; Iwanami, T; Suga, J; Nomura, Y; Kawanami, M; Ishikawa, I
2008-03-01
To investigate changes in bacterial counts in subgingival plaque from patients with acute periodontal abscess by IAI-PadoTest. Ninety-one patients were randomly allocated to either test or control groups. In all the patients, pockets with acute periodontal abscess were irrigated with sterilized physiological saline, and in the test group, 2% minocycline hydrochloride ointment was applied once into the pocket in addition. Subgingival plaque samples were collected by paper point before treatment and 7 days after treatment. The total bacterial count was determined and Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, were detected using IAI-PadoTest, a DNA/RNA probe method. The total bacterial count decreased in both groups, with a significant decrease in the test group. The counts and number of sites positive for P. gingivalis, T. forsythia and T. denticola significantly decreased in the test group after treatment, compared with those in the control group. Pocket depth decreased in the both groups, with a statistically significant decrease in the test group. Topical treatment with minocycline in pockets with acute periodontal abscess was effective in reducing the bacterial counts as shown by the microbiological investigation using PadoTest 4.5.
People Like Logical Truth: Testing the Intuitive Detection of Logical Value in Basic Propositions.
Directory of Open Access Journals (Sweden)
Hiroko Nakamura
Full Text Available Recent studies on logical reasoning have suggested that people are intuitively aware of the logical validity of syllogisms or that they intuitively detect conflict between heuristic responses and logical norms via slight changes in their feelings. According to logical intuition studies, logically valid or heuristic logic no-conflict reasoning is fluently processed and induces positive feelings without conscious awareness. One criticism states that such effects of logicality disappear when confounding factors such as the content of syllogisms are controlled. The present study used abstract propositions and tested whether people intuitively detect logical value. Experiment 1 presented four logical propositions (conjunctive, biconditional, conditional, and material implications regarding a target case and asked the participants to rate the extent to which they liked the statement. Experiment 2 tested the effects of matching bias, as well as intuitive logic, on the reasoners' feelings by manipulating whether the antecedent or consequent (or both of the conditional was affirmed or negated. The results showed that both logicality and matching bias affected the reasoners' feelings, and people preferred logically true targets over logically false ones for all forms of propositions. These results suggest that people intuitively detect what is true from what is false during abstract reasoning. Additionally, a Bayesian mixed model meta-analysis of conditionals indicated that people's intuitive interpretation of the conditional "if p then q" fits better with the conditional probability, q given p.
Mundlos, S; Rhodes, J B; Hofmann, A F
1987-09-01
A breath test for the detection of pancreatic insufficiency was developed and tested in rats. The test features the hydrophobic molecule cholesteryl-1-14C-octanoate, which liberates 14C-octanoic acid when hydrolyzed by carboxyl ester lipase (cholesterol esterase). The 14C-octanoate is absorbed passively and rapidly metabolized to 14CO2, which is excreted in expired air. The compound was administered as an emulsion of cholesteryl octanoate, triglyceride, and lecithin to rats with mild pancreatic insufficiency induced by injecting the pancreatic duct with zein. The animals had exocrine pancreatic hypofunction based on the enzyme content of pancreas at autopsy. Amylase was reduced by 97.1 +/- 1.4%, whereas chymotrypsin was reduced by 73 +/- 14%. The p-aminobenzoic acid test was abnormal at 1 wk (21.68 +/- 8.4%), but become normal at 3 months (72.08 +/- 5.8%) after zein injection. Despite this, the animals gained weight and absorbed fat normally. The 14CO2 excretion rate in the 110-min interval after feeding was significantly reduced to 60% of sham-operated animals. Peak 14CO2 collections 20 min after feeding were reduced by 75 +/- 11%. 14CO2 output was completely normalized by administration of pancreatin prior to the test meal. The results suggest that a sensitive, noninvasive method for detecting deficiency of pancreatic carboxyl ester lipase (cholesterol esterase) secretion in the rat has been developed.
The validity of upper-limb neurodynamic tests for detecting peripheral neuropathic pain.
Nee, Robert J; Jull, Gwendolen A; Vicenzino, Bill; Coppieters, Michel W
2012-05-01
The validity of upper-limb neurodynamic tests (ULNTs) for detecting peripheral neuropathic pain (PNP) was assessed by reviewing the evidence on plausibility, the definition of a positive test, reliability, and concurrent validity. Evidence was identified by a structured search for peer-reviewed articles published in English before May 2011. The quality of concurrent validity studies was assessed with the Quality Assessment of Diagnostic Accuracy Studies tool, where appropriate. Biomechanical and experimental pain data support the plausibility of ULNTs. Evidence suggests that a positive ULNT should at least partially reproduce the patient's symptoms and that structural differentiation should change these symptoms. Data indicate that this definition of a positive ULNT is reliable when used clinically. Limited evidence suggests that the median nerve test, but not the radial nerve test, helps determine whether a patient has cervical radiculopathy. The median nerve test does not help diagnose carpal tunnel syndrome. These findings should be interpreted cautiously, because diagnostic accuracy might have been distorted by the investigators' definitions of a positive ULNT. Furthermore, patients with PNP who presented with increased nerve mechanosensitivity rather than conduction loss might have been incorrectly classified by electrophysiological reference standards as not having PNP. The only evidence for concurrent validity of the ulnar nerve test was a case study on cubital tunnel syndrome. We recommend that researchers develop more comprehensive reference standards for PNP to accurately assess the concurrent validity of ULNTs and continue investigating the predictive validity of ULNTs for prognosis or treatment response.
Field Tests of the Magnetotelluric Method to Detect Gas Hydrates, Mallik, Mackenzie Delta, Canada
Craven, J. A.; Roberts, B.; Bellefleur, G.; Spratt, J.; Wright, F.; Dallimore, S. R.
2008-12-01
The magnetotelluric method is not generally utilized at extreme latitudes due primarily to difficulties in making the good electrical contact with the ground required to measure the electric field. As such, the magnetotelluric technique has not been previously investigated to direct detect gas hydrates in on-shore permafrost environments. We present the results of preliminary field tests at Mallik, Northwest Territories, Canada, that demonstrate good quality magnetotelluric data can be obtained in this environment using specialized electrodes and buffer amplifiers similar to those utilized by Wannamaker et al (2004). This result suggests that subsurface images from larger magnetotelluric surveys will be useful to complement other techniques to detect, quantify and characterize gas hydrates.
Dussart, Philippe; Petit, Laure; Labeau, Bhety; Bremand, Laetitia; Leduc, Alexandre; Moua, David; Matheus, Séverine; Baril, Laurence
2008-08-20
We compared the performance of two new commercial tests for the detection of dengue NS1 protein during the clinical phase of dengue virus (DENV) infection-an immunochromatographic test allowing rapid detection of the NS1 antigen, Dengue NS1 Ag STRIP (Bio-Rad Laboratories - Marnes La Coquette, France), and a two-step sandwich-format microplate enzyme-linked immunosorbent assay (ELISA), pan-E Dengue Early ELISA (Panbio - Brisbane, Australia)-with a one-step sandwich-format microplate ELISA, the Platelia Dengue NS1 Ag test (Bio-Rad). We tested 272 serum samples from patients with dengue disease. Of these, 222 were from patients with acute infection of one of the four dengue serotypes, detected by RT-PCR and/or virus isolation. Forty-eight acute-phase serum samples from patients not infected with dengue virus were also included. The sensitivity of the Platelia Dengue NS1 Ag test on acute serum samples (n = 222) was 87.4% (95% confidence interval: 82.3% to 91.5%); that of Dengue NS1 Ag STRIP was 81.5% (95% CI: 75.8% to 86.4%) after 15 minutes and 82.4% (95% CI: 76.8% to 87.2%) after 30 minutes. Both tests had a specificity of 100% (97.5% CI, one-sided test: 92.6% to 100.0%). The pan-E Dengue Early ELISA had a sensitivity of 60.4% (95% CI: 53.4% to 66.8%) and a specificity of 97.9% (95% CI: 88.9% to 99.9%). Our findings support the use of diagnostic tools based on the NS1 antigen detection for the diagnosis of acute DENV infection. The immunochromatographic test, Dengue NS1 Ag STRIP-the first rapid diagnostic test for DENV infection-was highly sensitive and specific, and would therefore be a suitable first-line test in the field. The pan-E Dengue Early ELISA was less sensitive than the Platelia test; this two-step ELISA should be combined with DENV IgM antibody detection for the diagnosis of DENV infection.
Directory of Open Access Journals (Sweden)
Philippe Dussart
Full Text Available BACKGROUND: We compared the performance of two new commercial tests for the detection of dengue NS1 protein during the clinical phase of dengue virus (DENV infection-an immunochromatographic test allowing rapid detection of the NS1 antigen, Dengue NS1 Ag STRIP (Bio-Rad Laboratories - Marnes La Coquette, France, and a two-step sandwich-format microplate enzyme-linked immunosorbent assay (ELISA, pan-E Dengue Early ELISA (Panbio - Brisbane, Australia-with a one-step sandwich-format microplate ELISA, the Platelia Dengue NS1 Ag test (Bio-Rad. METHODS: We tested 272 serum samples from patients with dengue disease. Of these, 222 were from patients with acute infection of one of the four dengue serotypes, detected by RT-PCR and/or virus isolation. Forty-eight acute-phase serum samples from patients not infected with dengue virus were also included. RESULTS: The sensitivity of the Platelia Dengue NS1 Ag test on acute serum samples (n = 222 was 87.4% (95% confidence interval: 82.3% to 91.5%; that of Dengue NS1 Ag STRIP was 81.5% (95% CI: 75.8% to 86.4% after 15 minutes and 82.4% (95% CI: 76.8% to 87.2% after 30 minutes. Both tests had a specificity of 100% (97.5% CI, one-sided test: 92.6% to 100.0%. The pan-E Dengue Early ELISA had a sensitivity of 60.4% (95% CI: 53.4% to 66.8% and a specificity of 97.9% (95% CI: 88.9% to 99.9%. CONCLUSION: Our findings support the use of diagnostic tools based on the NS1 antigen detection for the diagnosis of acute DENV infection. The immunochromatographic test, Dengue NS1 Ag STRIP-the first rapid diagnostic test for DENV infection-was highly sensitive and specific, and would therefore be a suitable first-line test in the field. The pan-E Dengue Early ELISA was less sensitive than the Platelia test; this two-step ELISA should be combined with DENV IgM antibody detection for the diagnosis of DENV infection.
Nordmann, Patrice; Jayol, Aurélie; Dobias, Jan; Poirel, Laurent
2017-04-01
The rapid aminoglycoside NP (Nordmann/Poirel) test was developed to rapidly identify multiple aminoglycoside (AG) resistance in Enterobacteriaceae It is based on the detection of the glucose metabolism related to enterobacterial growth in the presence of a defined concentration of amikacin plus gentamicin. Formation of acid metabolites was evidenced by a color change (orange to yellow) of the red phenol pH indicator. The rapid aminoglycoside NP test was evaluated by using bacterial colonies of 18 AG-resistant isolates producing 16S rRNA methylases, 20 AG-resistant isolates expressing AG-modifying enzymes (acetyl-, adenyl-, and phosphotransferases), and 10 isolates susceptible to AG. Its sensitivity and specificity were 100% and 97%, respectively, compared to the broth dilution method, which was taken as the gold standard for determining aminoglycoside resistance. The test is inexpensive, rapid (<2 h), and implementable worldwide. Copyright © 2017 American Society for Microbiology.
Crawshaw, Timothy R; Chanter, Jeremy I; McGoldrick, Adrian; Line, Kirsty
2014-02-07
Cases of Mycobacterium bovis infection South American camelids have been increasing in Great Britain. Current antemortem immunological tests have some limitations. Cases at post mortem examination frequently show extensive pathology. The feasibility of detecting Mycobacterium bovis DNA in clinical samples was investigated. A sensitive extraction methodology was developed and used on nasal swabs and faeces taken post-mortem to assess the potential for a PCR test to detect Mycobacterium bovis in clinical samples. The gross pathology of the studied South American camelids was scored and a significantly greater proportion of South American camelids with more severe pathology were positive in both the nasal swab and faecal PCR tests. A combination of the nasal swab and faecal PCR tests detected 63.9% of all the South American camelids with pathology that were tested. The results suggest that antemortem diagnosis of Mycobacterium bovis in South American camelids may be possible using a PCR test on clinical samples, however more work is required to determine sensitivity and specificity, and the practicalities of applying the test in the field.
Evaluation of a microbiological indicator test for antibiotic detection in ewe and goat milk.
Comunian, R; Paba, A; Dupré, I; Daga, E S; Scintu, M F
2010-12-01
Antibiotics are widely used for therapeutic and prophylactic purposes in dairy animals. The presence of residual antibiotics in milk could cause potentially serious problems in human health and have technological implication in the manufacturing of dairy products. The aim of this study was to evaluate Delvotest Accelerator (DSM Food Specialties, Delft, the Netherlands), a new system for a fully automated microbial test to detect antibiotic residues in ewe and goat milk. Forty-three samples of raw, whole, refrigerated bulk-tank milk samples (22 of ewe milk and 21 of goat milk) were analyzed during the whole lactation period. Four concentrations of 4 antibiotics were diluted in milk: penicillin G at 1, 2, 3, and 4 μg/L; sulfadiazine at 25, 50, 100, and 200 μg/L; tetracycline at 50, 100, 200, and 400 μg/L; and gentamicin at 25, 50, 100, and 200 μg/L. The detection limit of the Delvotest Accelerator was calculated as the range of antibiotic concentrations within which 95% of positive result lie. The range of detection limit of penicillin G and sulfadiazine was easily detected by Delvotest Accelerator at or below the European Union maximum residue limits, both for ewe and goat milk samples. In contrast, the system showed a lower ability to detect tetracycline and gentamicin both for ewe and goat milk samples. Very low percentages of false-positive outcomes were obtained. Lactation phase did not seem to be a crucial factor affecting the ability of the Delvotest Accelerator to detect spiked milk samples. A higher detection ability was observed for goat milk samples compared with ewe milk samples. A negative correlation between the percentage of positive milk samples detected and milk fat, protein, and lactose contents was observed for gentamicin only. Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
International Nuclear Information System (INIS)
McKague, H.L.; Kansa, E.; Kasameyer, P.W.
1992-01-01
Self-potential anomalies are naturally occurring, nearly stationary electric fields that are detected by measuring the potential difference between two points on (or in) the ground. SP anomalies arise from a number of causes: principally electrochemical reactions, and heat and fluid flows. SP is routinely used to locate mineral deposits, geothermal systems, and zones of seepage. This paper is a progress report on our work toward detecting explosion-related SP signals at the Nevada Test Site (NTS) and in understanding the physics of these anomalies that persist and continue changing over periods of time that range from months to years. As background, we also include a brief description of how SP signals arise, and we mention their use in other areas such as exploring for geothermal resources and locating seepage through dams. Between the years 1988 and 1991, we surveyed the areas around seven underground nuclear tests for persistent SP anomalies. We not only detected anomalies, but we also found that various phenomena could be contributing to them and that we did not know which of these were actually occurring. We analyzed our new data with existing steady state codes and with a newly developed time-dependent thermal modeling code. Our results with the new code showed that the conductive decay of the thermal pulse from an underground nuclear test could produce many of the observed signals, and that others are probably caused by movement of fluid induced by the explosion. 25 refs
Zarei, Mehdi; Ghorbanpour, Masoud; Tajbakhsh, Samaneh; Mosavari, Nader
2017-08-01
Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne's disease, a chronic enteritis in cattle and other domestic and wild ruminants. The presence of MAP in tissues other than intestines and associated lymph nodes, such as meat and liver, is a potential public health concern. In the present study, the relationship between the results of rapid diagnostic tests of the Johne's disease, such as serum ELISA, rectal scraping PCR, and acid-fast staining, and the presence of MAP in liver was evaluated. Blood, liver, and rectal scraping samples were collected from 200 slaughtered cattle with unknown Johne's disease status. ELISA was performed to determine the MAP antibody activity in the serum. Acid-fast staining was performed on rectal scraping samples, and PCR was performed on rectal scraping and liver samples. PCR-positive liver samples were used for mycobacterial culture. Overall, the results of this study demonstrated that MAP can be detected and cultured from liver of slaughtered cattle and rapid diagnostic tests of Johne's disease have limited value in detecting cattle with MAP infection in liver. These findings show that the presence of MAP in liver tissue may occur in cows with negative results for rapid diagnostic tests and vice versa. Hence, liver might represent another possible risk of human exposure to MAP. Given concerns about a potential zoonotic role for MAP, these results show the necessity to find new methods for detecting cattle with MAP disseminated infection.
Felipo, Vicente; Urios, Amparo; Giménez-Garzó, Carla; Cauli, Omar; Andrés-Costa, Maria-Jesús; González, Olga; Serra, Miguel A; Sánchez-González, Javier; Aliaga, Roberto; Giner-Durán, Remedios; Belloch, Vicente; Montoliu, Carmina
2014-09-07
To assess whether non invasive blood flow measurement by arterial spin labeling in several brain regions detects minimal hepatic encephalopathy. Blood flow (BF) was analyzed by arterial spin labeling (ASL) in different brain areas of 14 controls, 24 cirrhotic patients without and 16 cirrhotic patients with minimal hepatic encephalopathy (MHE). Images were collected using a 3 Tesla MR scanner (Achieva 3T-TX, Philips, Netherlands). Pulsed ASL was performed. Patients showing MHE were detected using the battery Psychometric Hepatic Encephalopathy Score (PHES) consisting of five tests. Different cognitive and motor functions were also assessed: alterations in selective attention were evaluated using the Stroop test. Patients and controls also performed visuo-motor and bimanual coordination tests. Several biochemical parameters were measured: serum pro-inflammatory interleukins (IL-6 and IL-18), 3-nitrotyrosine, cGMP and nitrates+nitrites in plasma, and blood ammonia. Bivariate correlations were evaluated. In patients with MHE, BF was increased in cerebellar hemisphere (P = 0.03) and vermis (P = 0.012) and reduced in occipital lobe (P = 0.017). BF in cerebellar hemisphere was also increased in patients without MHE (P = 0.02). Bimanual coordination was impaired in patients without MHE (P = 0.05) and much more in patients with MHE (P battery and with CFF. BF in cerebellar hemisphere correlates with plasma cGMP and nitric oxide (NO) metabolites. BF in vermis cerebellar also correlates with NO metabolites and with 3-nitrotyrosine. IL-18 in plasma correlates with BF in thalamus and occipital lobe. Non invasive BF determination in cerebellum using ASL may detect MHE earlier than the PHES. Altered NO-cGMP pathway seems to be associated to altered BF in cerebellum.
Present trends in the detection of myocardial viability using nuclear cardiology tests
International Nuclear Information System (INIS)
Peix Gonzalez, Amalia; Garcia Barreto, David
1999-01-01
The myocardial viability diagnosis is important for those who will undergo myocardial revascularization whether by surgery or coronary angioplasty. Our purpose is to present some of the present trends in the detection of myocardial viability using nuclear cardiology tests. Emphasis is made on the estimation of radiopharmaceutical uptake and the use of vasodilators in perfusion scintigraphy mainly with technetium-labeled compounds. Also, the current possibilities for a myocardial metabolism study using single-photon emission-computed tomography as well as some clinical implications of myocardial viability are set forth
DEFF Research Database (Denmark)
Enøe, Claes; Andersen, Søren; Sørensen, Vibeke
2001-01-01
Latent-class models were used to determine the sensitivity, specificity and predictive values of a polyclonal blocking enzyme-linked immunosorbent assay (ELISA) and a modified complement-fixation test (CFT) when there was no reference test. The tests were used for detection of antibodies against ...
Directory of Open Access Journals (Sweden)
H Ghasemian safaei
2005-01-01
Full Text Available Background: This study was conducted to compare the efficacy of enzyme-linked immunosorbent assay (ELISA for detecting anti-Helicobacter pylori (H. pylori specific IgG antibodies in specimens of oral fluid and serum with bacteriological tests. Methods: Antral biopsy specimens, as well as serum and oral fluid samples were collected from 97 patients who underwent upper gastrointestinal endoscopy. The presence or absence of current H. pylori infection was determined by culture, histology and urease detection. Anti-H. pylori specific IgG was detected in serum and oral fluid, using an established lab-made, and a commercial ELISA kit. The obtained data were compared with results of bacteriological tests. Results: In all, 62 (64% of 97 patients were positive for H. pylori by one or more of the gold standard tests (culture, histology and urease detection. Lab-made enzyme-linked immunoassay of oral fluid had a sensitivity and specificity of 92% and 83% respectively. A sensitivity and specificity of 87% and 83%, respectively, was obtained with the commercial kit. Lab-made enzyme-linked immunoassay of serum samples had a sensitivity and specificity of 90% and 88%, respectively. A sensitivity of 86% and specificity of 86% was obtained with the commercial kit. Conclusion: Detection of anti-H. pylori specific IgG in oral fluid by ELISA is comparable in sensitivity and specificity with serum based methods. Oral fluid based ELISA could provide a reliable, non-invasive method for the diagnosis of H. pylori infection. Saliva testing may have a role in epidemiological studies. Keywords: Helicobacter pylori, ELISA, Oral fluid
[Diagnostic advantages of the test system "DS-EIA-HBsAg-0.01" for detection of HBV surface antigen].
Egorova, N I; Pyrenkova, I Iu; Igolkina, S N; Sharipova, I N; Puzyrev, V F; Obriadina, A P; Burkov, A N; Kornienko, N V; Fields, H A; Korovkin, A S; Shalunova, N V; Bektemirov, T A; Kuznetsov, K V; Koshcheeva, N A; Ulanova, T I
2009-01-01
The new highly sensitive test system "DS-EIA-HBsAg-0.01" (Priority Certificate No. 2006129019 of August 10, 2006) in detecting hepatitis B surface antigen (HBsAg) was assessed. The sensitivity of the test was estimated using the federal standards sample HBsAg 42-28-311-06, panels' samples Boston Biomedica Inc. (West Bridgewater, Mass, USA) and ZeptoMetrix Corp. (Buffalo, NY, USA). The findings have indicated that "DS-EIA-HBsAg-0.01" is equally effective in detecting different subtypes of HBsAg during a seroconversion period earlier than alternative assays. Along with its high analytical and diagnostic sensitivity, the system shows a high diagnostic specificity.
Donders, Gilbert G G; Marconi, Camila; Bellen, Gert
2010-01-01
Accessing vaginal pH is fundamental during gynaecological visit for the detection of abnormal vaginal flora (AVF), but use of pH strips may be time-consuming and difficult to interpret. The aim of this study was to evaluate the VS-SENSE test (Common Sense Ltd, Caesarea, Israel) as a tool for the diagnosis of AVF and its correlation with abnormal pH and bacterial vaginosis (BV). The study population consisted of 45 women with vaginal pH ≥ 4.5 and 45 women with normal pH. Vaginal samples were evaluated by VS-SENSE test, microscopy and microbiologic cultures. Comparing with pH strips results, VS-SENSE test specificity was 97.8% and sensitivity of 91%. All severe cases of BV and aerobic vaginitis (AV) were detected by the test. Only one case with normal pH had an unclear result. Concluding, VS-SENSE test is easy to perform, and it correlates with increased pH, AVF, and the severe cases of BV and AV.
Bwire, Godfrey; Orach, Christopher Garimoi; Abdallah, Dauda; Debes, Amanda Kay; Kagirita, Atek; Ram, Malathi; Sack, David A
2017-11-21
Detection, confirmation and monitoring of cholera outbreaks in many developing countries including Uganda is a big challenge due to lack of the required resources and the time the test takes. Culture method which takes 24-48 h to get the feedback and requires highly skilled laboratory staff plus other complex resources is the standard test. This study evaluated the new cholera rapid detection method that relies on Crystal VC dipsticks after enrichment with alkaline peptone water (APW) against the culture method for monitoring the progress of cholera outbreaks in rural setting. We conducted the study between March and June 2015. Fresh stool samples and rectal swabs were incubated in 1% APW for 6 h at room temperature before testing with RDT following the manufacturer's instruction. The same stool sample was cultured to isolate V. cholerae in the standard manner. We also reviewed patient registers to epidemiologically describe the cholera epidemic. We tested stool from 102 consenting suspected cholera patients reporting during daytime at Bwera Hospital (n = 69), Kilembe Mines Hospital (n = 4) and Kinyabwama Health Centre (n = 29). Ninety one (91) samples were positive and nine samples were negative according to both methods. One (1) sample was positive only by dipstick and one sample was positive only by culture (sensitivity of 99%, specificity of 90%, Positive Predictive Value of 99% and Negative Predictive Value of 90%). Overall, 146 suspected cholera cases and two deaths, (case fatality rate of 1.36%) were recorded during the study period. Among the cases aged 1-9 years, 63% (50/79) were males while in those aged 20-49 years, 76% (34/45) were females. Our findings showed that the modified dipstick test after enrichment with 1% APW had high level of accuracy in detection of V. cholerae and is quick, affordable alternative cholera outbreak monitoring tool in resource constrained settings. However, culture method should remain for cholera epidemic
Directory of Open Access Journals (Sweden)
Godfrey Bwire
2017-11-01
Full Text Available Abstract Background Detection, confirmation and monitoring of cholera outbreaks in many developing countries including Uganda is a big challenge due to lack of the required resources and the time the test takes. Culture method which takes 24–48 h to get the feedback and requires highly skilled laboratory staff plus other complex resources is the standard test. This study evaluated the new cholera rapid detection method that relies on Crystal VC dipsticks after enrichment with alkaline peptone water (APW against the culture method for monitoring the progress of cholera outbreaks in rural setting. Methods We conducted the study between March and June 2015. Fresh stool samples and rectal swabs were incubated in 1% APW for 6 h at room temperature before testing with RDT following the manufacturer’s instruction. The same stool sample was cultured to isolate V. cholerae in the standard manner. We also reviewed patient registers to epidemiologically describe the cholera epidemic. Results We tested stool from 102 consenting suspected cholera patients reporting during daytime at Bwera Hospital (n = 69, Kilembe Mines Hospital (n = 4 and Kinyabwama Health Centre (n = 29. Ninety one (91 samples were positive and nine samples were negative according to both methods. One (1 sample was positive only by dipstick and one sample was positive only by culture (sensitivity of 99%, specificity of 90%, Positive Predictive Value of 99% and Negative Predictive Value of 90%. Overall, 146 suspected cholera cases and two deaths, (case fatality rate of 1.36% were recorded during the study period. Among the cases aged 1–9 years, 63% (50/79 were males while in those aged 20–49 years, 76% (34/45 were females. Conclusions Our findings showed that the modified dipstick test after enrichment with 1% APW had high level of accuracy in detection of V. cholerae and is quick, affordable alternative cholera outbreak monitoring tool in resource constrained
Utilization of urea micro dose with 14 C in breath test to detect the Helicobacter pylori
International Nuclear Information System (INIS)
Chausson, Yvon; Coelho, Luiz Gonzaga V.; Passos, Maria do Carmo F.; Andrade, Angela A.M.; Simal, Carlos J.R.; Paula Castro, Luiz de; Fernandes, M.L.; Yazaki, F.R.
1995-01-01
A lower dose is used in the 14 C-urea breath test to detect the Helicobacter pylori (Hp). Such dose produce trivial radiation doses. The results shown that the use of this desirable dose is possible. (author). 4 refs., 1 fig
Rubaba, O; Chimbari, M J; Soko, W; Manyangadze, T; Mukaratirwa, S
2018-06-01
Circulating cathodic antigen (CCA) tests for schistosomiasis are fast and less complicated allowing making them good candidates for routine qualitative screening for schistosomiasis at point of care. The urine-CCA has been evaluated for detection of S. mansoni with promising results. Its specificity and consistency in detecting S. haematobium infection in different endemic regions has been variable. This study validated a rapid urine-CCA cassette test for qualitative detection of S. haematobium infection in an S. haematobium endemic area with low S. mansoni prevalence. Microscopic examination for the standard urine filtration technique was used to validate the commercially available urine-CCA cassette test (rapid medical diagnostics ® ). The validation was done in a sample of primary school pupils (n = 420) aged 10-15 years in schools in the Jozini Municipality, KZN. There was a relationship between infection intensity and a positive urine-CCA test. Using the urine filtration method as the gold standard, the prevalence for S. haematobium was 40%, the accuracy of the CCA kit was 54.8%, sensitivity was 68.1% while the specificity was 45.8%. The positive predictive value was 45.82% while the negative predictive value was 68.05%. Both the urine filtration and the urine-CCA methods detected heavy (≥50 eggs/10 mL urine) and light infections at statistically significant levels. The overall accuracy, sensitivity and specificity of the urine-CCA cassette test were low. The urine-CCA cassette test performed much better for heavy infections than low infections (p < 0.05) implying that the kit may not be suitable for low endemic areas. Copyright © 2018 Elsevier B.V. All rights reserved.
Thiele, Maja; Madsen, Bjørn Stæhr; Hansen, Janne Fuglsang; Detlefsen, Sönke; Antonsen, Steen; Krag, Aleksander
2018-04-01
Alcohol is the leading cause of cirrhosis and liver-related mortality, but we lack serum markers to detect compensated disease. We compared the accuracy of the Enhanced Liver Fibrosis test (ELF), the FibroTest, liver stiffness measurements (made by transient elastography and 2-dimensional shear-wave elastography), and 6 indirect marker tests in detection of advanced liver fibrosis (Kleiner stage ≥F3). We performed a prospective study of 10 liver fibrosis markers (patented and not), all performed on the same day. Patients were recruited from primary centers (municipal alcohol rehabilitation, n = 128; 6% with advanced fibrosis) and secondary health care centers (hospital outpatient clinics, n = 161; 36% with advanced fibrosis) in the Region of Southern Denmark from 2013 through 2016. Biopsy-verified fibrosis stage was used as the reference standard. The primary aim was to validate ELF in detection of advanced fibrosis in patients with alcoholic liver disease recruited from primary and secondary health care centers, using the literature-based cutoff value of 10.5. Secondary aims were to assess the diagnostic accuracy of ELF for significant fibrosis and cirrhosis and to determine whether combinations of fibrosis markers increase diagnostic yield. The ELF identified patients with advanced liver fibrosis with an area under the receiver operating characteristic curve (AUROC) of 0.92 (95% confidence interval 0.89-0.96); findings did not differ significantly between patients from primary vs secondary care (P = .917). ELF more accurately identified patients with advanced liver fibrosis than indirect marker tests, but ELF and FibroTest had comparable diagnostic accuracies (AUROC of FibroTest, 0.90) (P = .209 for comparison with ELF). Results from the ELF and FibroTest did not differ significantly from those of liver stiffness measurement in intention-to-diagnose analyses (AUROC for transient elastography, 0.90), but did differ in the per-protocol analysis (AUROC for
Directory of Open Access Journals (Sweden)
Nicola M Zetola
2008-07-01
Full Text Available Populations at highest risk for HIV infection face multiple barriers to HIV testing. To facilitate HIV testing procedures, the San Francisco General Hospital Medical Center eliminated required written patient consent for HIV testing in its medical settings in May 2006. To describe the change in HIV testing rates in different hospital settings and populations after the change in HIV testing policy in the SFDH medical center, we performed an observational study using interrupted time series analysis.Data from all patients aged 18 years and older seen from January 2003 through June 2007 at the San Francisco Department of Public Health (SFDPH medical care system were included in the analysis. The monthly HIV testing rate per 1000 had patient-visits was calculated for the overall population and stratified by hospital setting, age, sex, race/ethnicity, homelessness status, insurance status and primary language.By June 2007, the average monthly rate of HIV tests per 1000 patient-visits increased 4.38 (CI, 2.17-6.60, p<0.001 over the number predicted if the policy change had not occurred (representing a 44% increase. The monthly average number of new positive HIV tests increased from 8.9 (CI, 6.3-11.5 to 14.9 (CI, 10.6-19.2, p<0.001, representing a 67% increase. Although increases in HIV testing were seen in all populations, populations at highest risk for HIV infection, particularly men, the homeless, and the uninsured experienced the highest increases in monthly HIV testing rates after the policy change.The elimination of the requirement for written consent in May 2006 was associated with a significant and sustained increase in HIV testing rates and HIV case detection in the SFDPH medical center. Populations facing the higher barriers to HIV testing had the highest increases in HIV testing rates and case detection in response to the policy change.
Lee, Posen; Lu, Wen-Shian; Liu, Chin-Hsuan; Lin, Hung-Yu; Hsieh, Ching-Lin
2017-12-08
The d2 Test of Attention (D2) is a commonly used measure of selective attention for patients with schizophrenia. However, its test-retest reliability and minimal detectable change (MDC) are unknown in patients with schizophrenia, limiting its utility in both clinical and research settings. The aim of the present study was to examine the test-retest reliability and MDC of the D2 in patients with schizophrenia. A rater administered the D2 on 108 patients with schizophrenia twice at a 1-month interval. Test-retest reliability was determined through the calculation of the intra-class correlation coefficient (ICC). We also carried out Bland-Altman analysis, which included a scatter plot of the differences between test and retest against their mean. Systematic biases were evaluated by use of a paired t-test. The ICCs for the D2 ranged from 0.78 to 0.94. The MDCs (MDC%) of the seven subscores were 102.3 (29.7), 19.4 (85.0), 7.2 (94.6), 21.0 (69.0), 104.0 (33.1), 105.0 (35.8), and 7.8 (47.8), which represented limited-to-acceptable random measurement error. Trends in the Bland-Altman plots of the omissions (E1), commissions (E2), and errors (E) were noted, presenting that the data had heteroscedasticity. According to the results, the D2 had good test-retest reliability, especially in the scores of TN, TN-E, and CP. For the further research, finding a way to improve the administration procedure to reduce random measurement error would be important for the E1, E2, E, and FR subscores. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Isothermal Amplification for MicroRNA Detection: From the Test Tube to the Cell.
Deng, Ruijie; Zhang, Kaixiang; Li, Jinghong
2017-04-18
MicroRNAs (miRNAs) are a class of small noncoding RNAs that act as pivotal post-transcriptional regulators of gene expression, thus involving in many fundamental cellular processes such as cell proliferation, migration, and canceration. The detection of miRNAs has attracted significant interest, as abnormal miRNA expression is identified to contribute to serious human diseases such as cancers. Particularly, miRNAs in peripheral blood have recently been recognized as important biomarkers potential for liquid biopsy. Furthermore, as miRNAs are expressed heterogeneously in different cells, investigations into single-cell miRNA expression will be of great value for resolving miRNA-mediated regulatory circuits and the complexity and heterogeneity of miRNA-related diseases. Thus, the development of miRNA detection methods, especially for complex clinic samples and single cells is in great demand. In this Account, we will present recent progress in the design and application of isothermal amplification enabling miRNA detection transition from the test tube to the clinical sample and single cell, which will significantly advance our knowledge of miRNA functions and disease associations, as well as its translation in clinical diagnostics. miRNAs present a huge challenge in detection because of their extremely short length (∼22 nucleotides) and sequence homology (even with only single-nucleotide variation). The conventional golden method for nucleic acid detection, quantitative PCR (qPCR), is not amenable to directly detecting short RNAs and hardly enables distinguishing between miRNA family members with very similar sequences. Alternatively, isothermal amplification has emerged as a powerful method for quantification of nucleic acids and attracts broad interest for utilization in developing miRNA assays. Compared to PCR, isothermal amplification can be performed without precise control of temperature cycling and is well fit for detecting short RNA or DNA. We and other
Shariati, Laleh; Validi, Majid; Tabatabaiefar, Mohammad Amin; Karimi, Ali; Nafisi, Mohammad Reza
2010-12-01
Methicillin-resistant Staphylococcus aureus (MRSA) is a nosocomial pathogen. Our main objective was to compare oxacillin disk test, oxacillin E-test, and oxacillin agar screen for detection of methicillin resistance in S. aureus, using real-time PCR for mecA as the "gold standard" comparison assay. 196 S. aureus isolates were identified out of 284 Staphylococcus isolates. These isolates were screened for MRSA with several methods: disk diffusion, agar screen (6.0 μg/ml), oxacillin E-test, and real-time PCR for detection of mecA gene. Of the 196 S. aureus isolates tested, 96 isolates (49%) were mecA-positive and 100 isolates (51%) mecA-negative. All methods tested had a statistically significant agreement with real-time PCR. E-test was 100% sensitive and specific for mecA presence. The sensitivity and specificity of oxacillin agar screen method were 98 and 99%, respectively and sensitivity and specificity of oxacillin disk diffusion method were 95 and 93%, respectively. In the present study, oxacillin E-test is proposed as the best phenotypic method. For economic reasons, the oxacillin agar screen method (6.0 μg/ml), which is suitable for the detection of MRSA, is recommended due to its accuracy and low cost.
Active Fault Detection Based on a Statistical Test
DEFF Research Database (Denmark)
Sekunda, André Krabdrup; Niemann, Hans Henrik; Poulsen, Niels Kjølstad
2016-01-01
In this paper active fault detection of closed loop systems using dual Youla-Jabr-Bongiorno-Kucera(YJBK) parameters is presented. Until now all detector design for active fault detection using the dual YJBK parameters has been based on CUSUM detectors. Here a method for design of a matched filter...
Field demonstration of CO2 leakage detection in potable aquifers with a pulselike CO2-release test.
Yang, Changbing; Hovorka, Susan D; Delgado-Alonso, Jesus; Mickler, Patrick J; Treviño, Ramón H; Phillips, Straun
2014-12-02
This study presents two field pulselike CO2-release tests to demonstrate CO2 leakage detection in a shallow aquifer by monitoring groundwater pH, alkalinity, and dissolved inorganic carbon (DIC) using the periodic groundwater sampling method and a fiber-optic CO2 sensor for real-time in situ monitoring of dissolved CO2 in groundwater. Measurements of groundwater pH, alkalinity, DIC, and dissolved CO2 clearly deviated from their background values, showing responses to CO2 leakage. Dissolved CO2 observed in the tests was highly sensitive in comparison to groundwater pH, DIC, and alkalinity. Comparison of the pulselike CO2-release tests to other field tests suggests that pulselike CO2-release tests can provide reliable assessment of geochemical parameters indicative of CO2 leakage. Measurements by the fiber-optic CO2 sensor, showing obvious leakage signals, demonstrated the potential of real-time in situ monitoring of dissolved CO2 for leakage detection at a geologic carbon sequestration (GCS) site. Results of a two-dimensional reactive transport model reproduced the geochemical measurements and confirmed that the decrease in groundwater pH and the increases in DIC and dissolved CO2 observed in the pulselike CO2-release tests were caused by dissolution of CO2 whereas alkalinity was likely affected by carbonate dissolution.
F.N. Martin; M.D. Coffey; K. Zeller; R.C. Hamelin; P. Tooley; M. Garbelotto; K.J.D. Hughes; T. Kubisiak; G.J. Bilodeau; L. Levy; C. Blomquist; P.H. Berger
2009-01-01
Given the importance of Phytophthora ramorum from a regulatory standpoint, it is imperative that molecular markers for pathogen detection are fully tested to evaluate their specificity in detection of the pathogen. In an effort to evaluate 11 reported diagnostic techniques, we assembled a standardized DNA library using accessions from the World...
Energy Technology Data Exchange (ETDEWEB)
Dong, Bing; Lam, Khee Poh; Zhang, Rui; Chiou, Yun-Shang [Center for Building Performance and Diagnostics, Carnegie Mellon University, Pittsburgh, PA 15213 (United States); Andrews, Burton; Hoeynck, Michael; Benitez, Diego [Research and Technology Center, Robert BOSCH LLC, Pittsburgh, PA 15212 (United States)
2010-07-15
This paper describes a large-scale wireless and wired environmental sensor network test-bed and its application to occupancy detection in an open-plan office building. Detection of occupant presence has been used extensively in built environments for applications such as demand-controlled ventilation and security; however, the ability to discern the actual number of people in a room is beyond the scope of current sensing techniques. To address this problem, a complex sensor network is deployed in the Robert L. Preger Intelligent Workplace comprising a wireless ambient-sensing system, a wired carbon dioxide sensing system, and a wired indoor air quality sensing system. A wired camera network is implemented as well for establishing true occupancy levels to be used as ground truth information for deriving algorithmic relationships with the environment conditions. To our knowledge, this extensive and diverse ambient-sensing infrastructure of the ITEST setup as well as the continuous data-collection capability is unprecedented. Final results indicate that there are significant correlations between measured environmental conditions and occupancy status. An average of 73% accuracy on the occupancy number detection was achieved by Hidden Markov Models during testing periods. This paper serves as an exploration to the research of ITEST for occupancy detection in offices. In addition, its utility extends to a wide variety of other building technology research areas such as human-centered environmental control, security, energy efficient and sustainable green buildings. (author)
Cabada, Miguel M.; Malaga, Jose L.; Castellanos-Gonzalez, Alejandro; Bagwell, Kelli A.; Naeger, Patrick A.; Rogers, Hayley K.; Maharsi, Safa; Mbaka, Maryann; White, A. Clinton
2017-01-01
Fasciola hepatica is the most widely distributed trematode infection in the world. Control efforts may be hindered by the lack of diagnostic capacity especially in remote endemic areas. Polymerase chain reaction (PCR)–based methods offer high sensitivity and specificity but require expensive technology. However, the recombinase polymerase amplification (RPA) is an efficient isothermal method that eliminates the need for a thermal cycler and has a high deployment potential to resource-limited settings. We report on the characterization of RPA and PCR tests to detect Fasciola infection in clinical stool samples with low egg burdens. The sensitivity of the RPA and PCR were 87% and 66%, respectively. Both tests were 100% specific showing no cross-reactivity with trematode, cestode, or nematode parasites. In addition, RPA and PCR were able to detect 47% and 26% of infections not detected by microscopy, respectively. The RPA adapted to a lateral flow platform was more sensitive than gel-based detection of the reaction products. In conclusion, the Fasciola RPA is a highly sensitive and specific test to diagnose chronic infection using stool samples. The Fasciola RPA lateral flow has the potential for deployment to endemic areas after further characterization. PMID:27821691
Weir, Nichola-Jane M; Pattison, Sally H; Kearney, Paddy; Stafford, Bob; Gormley, Gerard J; Crockard, Martin A; Gilpin, Deirdre F; Tunney, Michael M; Hughes, Carmel M
2018-01-01
Urinary Tract Infections (UTIs) are common bacterial infections, second only to respiratory tract infections and particularly prevalent within primary care. Conventional detection of UTIs is culture, however, return of results can take between 24 and 72 hours. The introduction of a point of care (POC) test would allow for more timely identification of UTIs, facilitating improved, targeted treatment. This study aimed to obtain consensus on the criteria required for a POC UTI test, to meet patient need within primary care. Criteria for consideration were compiled by the research team. These criteria were validated through a two-round Delphi process, utilising an expert panel of healthcare professionals from across Europe and United States of America. Using web-based questionnaires, panellists recorded their level of agreement with each criterion based on a 5-point Likert Scale, with space for comments. Using median response, interquartile range and comments provided, criteria were accepted/rejected/revised depending on pre-agreed cut-off scores. The first round questionnaire presented thirty-three criteria to the panel, of which 22 were accepted. Consensus was not achieved for the remaining 11 criteria. Following response review, one criterion was removed, while after revision, the remaining 10 criteria entered the second round. Of these, four were subsequently accepted, resulting in 26 criteria considered appropriate for a POC test to detect urinary infections. This study generated an approved set of criteria for a POC test to detect urinary infections. Criteria acceptance and comments provided by the healthcare professionals also supports the development of a multiplex point of care UTI test.
Directory of Open Access Journals (Sweden)
Karen R Steingart
2007-06-01
Full Text Available BACKGROUND: The global tuberculosis epidemic results in nearly 2 million deaths and 9 million new cases of the disease a year. The vast majority of tuberculosis patients live in developing countries, where the diagnosis of tuberculosis relies on the identification of acid-fast bacilli on unprocessed sputum smears using conventional light microscopy. Microscopy has high specificity in tuberculosis-endemic countries, but modest sensitivity which varies among laboratories (range 20% to 80%. Moreover, the sensitivity is poor for paucibacillary disease (e.g., pediatric and HIV-associated tuberculosis. Thus, the development of rapid and accurate new diagnostic tools is imperative. Immune-based tests are potentially suitable for use in low-income countries as some test formats can be performed at the point of care without laboratory equipment. Currently, dozens of distinct commercial antibody detection tests are sold in developing countries. The question is "do they work?" METHODS AND FINDINGS: We conducted a systematic review to assess the accuracy of commercial antibody detection tests for the diagnosis of pulmonary tuberculosis. Studies from all countries using culture and/or microscopy smear for confirmation of pulmonary tuberculosis were eligible. Studies with fewer than 50 participants (25 patients and 25 control participants were excluded. In a comprehensive search, we identified 68 studies. The results demonstrate that (1 overall, commercial tests vary widely in performance; (2 sensitivity is higher in smear-positive than smear-negative samples; (3 in studies of smear-positive patients, Anda-TB IgG by enzyme-linked immunosorbent assay shows limited sensitivity (range 63% to 85% and inconsistent specificity (range 73% to 100%; (4 specificity is higher in healthy volunteers than in patients in whom tuberculosis disease is initially suspected and subsequently ruled out; and (5 there are insufficient data to determine the accuracy of most
Directory of Open Access Journals (Sweden)
Cabral Soares F
2014-12-01
Full Text Available Fernanda Cabral Soares,1 Thaís Cristina Galdino de Oliveira,1 Liliane Dias e Dias de Macedo,1 Alessandra Mendonça Tomás,1 Domingos Luiz Wanderley Picanço-Diniz,2 João Bento-Torres,1,3 Natáli Valim Oliver Bento-Torres,1,3 Cristovam Wanderley Picanço-Diniz1 1Universidade Federal do Pará, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Laboratório de Investigações em Neurodegeneração e Infecção Belém, Pará, Brazil; 2Universidade Federal do Oeste do Pará, Núcleo Universitário de Oriximiná, Oriximiná, Pará, Brazil; 3Faculdade de Fisioterapia e Terapia Ocupacional, Universidade Federal do Pará, Belém, Pará, BrazilObjective: The recognition of the limits between normal and pathological aging is essential to start preventive actions. The aim of this paper is to compare the Cambridge Neuropsychological Test Automated Battery (CANTAB and language tests to distinguish subtle differences in cognitive performances in two different age groups, namely young adults and elderly cognitively normal subjects.Method: We selected 29 young adults (29.9±1.06 years and 31 older adults (74.1±1.15 years matched by educational level (years of schooling. All subjects underwent a general assessment and a battery of neuropsychological tests, including the Mini Mental State Examination, visuospatial learning, and memory tasks from CANTAB and language tests. Cluster and discriminant analysis were applied to all neuropsychological test results to distinguish possible subgroups inside each age group.Results: Significant differences in the performance of aged and young adults were detected in both language and visuospatial memory tests. Intragroup cluster and discriminant analysis revealed that CANTAB, as compared to language tests, was able to detect subtle but significant differences between the subjects.Conclusion: Based on these findings, we concluded that, as compared to language tests, large-scale application
Zhang, Qingyang
2018-05-16
Differential co-expression analysis, as a complement of differential expression analysis, offers significant insights into the changes in molecular mechanism of different phenotypes. A prevailing approach to detecting differentially co-expressed genes is to compare Pearson's correlation coefficients in two phenotypes. However, due to the limitations of Pearson's correlation measure, this approach lacks the power to detect nonlinear changes in gene co-expression which is common in gene regulatory networks. In this work, a new nonparametric procedure is proposed to search differentially co-expressed gene pairs in different phenotypes from large-scale data. Our computational pipeline consisted of two main steps, a screening step and a testing step. The screening step is to reduce the search space by filtering out all the independent gene pairs using distance correlation measure. In the testing step, we compare the gene co-expression patterns in different phenotypes by a recently developed edge-count test. Both steps are distribution-free and targeting nonlinear relations. We illustrate the promise of the new approach by analyzing the Cancer Genome Atlas data and the METABRIC data for breast cancer subtypes. Compared with some existing methods, the new method is more powerful in detecting nonlinear type of differential co-expressions. The distance correlation screening can greatly improve computational efficiency, facilitating its application to large data sets.
International Nuclear Information System (INIS)
Henze, E.; Malfertheiner, P.; Clausen, M.; Burkhardt, H.; Adam, W.E.
1990-01-01
A carbon-14 ( 14 C) urea breath test for detecting Helicobacter pylori with multiple breath sampling was developed. Carbon-14-urea (110 kBq) administered orally to 18 normal subjects and to 82 patients with Helicobacter infection. The exhaled 14 C-labeled CO 2 was trapped at 10-min intervals for 90 min. The total 14 C activity exhaled over 90 min was integrated and expressed in %activity of the total dose given. In normals, a mean of 0.59% +/- 0.24% was measured, resulting in an upper limit of normal of 1.07%. In 82 patients, a sensitivity of 90.2%, a specificity of 83.8%, and a positive predictive value of 90.2% was found. The single probes at intervals of 40-60 min correlated best with the integrated result, with r ranging from 0.986 to 0.990. The test's diagnostic accuracy did not change at all when reevaluated with the 40-, 50-, or 60-min sample data alone. Thus, the 14 C-urea breath test can be applied routinely as a noninvasive, low-cost and one-sample test with high diagnostic accuracy in detecting Helicobacter pylori colonization
DEFF Research Database (Denmark)
Conradsen, Knut; Nielsen, Allan Aasbjerg; Schou, Jesper
2003-01-01
. Based on this distribution, a test statistic for equality of two such matrices and an associated asymptotic probability for obtaining a smaller value of the test statistic are derived and applied successfully to change detection in polarimetric SAR data. In a case study, EMISAR L-band data from April 17...... to HH, VV, or HV data alone, the derived test statistic reduces to the well-known gamma likelihood-ratio test statistic. The derived test statistic and the associated significance value can be applied as a line or edge detector in fully polarimetric SAR data also....
Energy Technology Data Exchange (ETDEWEB)
Barnett, D. Brent; Gee, Glendon W.; Sweeney, Mark D.
2001-07-31
As part of the Leak Detection, Monitoring and Mitigation (LDMM) program conducted by CH2M HILL 105-A during FY 2001. These tests are being conducted to assess the applicability of these methods (Electrical Resistance Tomography [ERT], High Resolution Resistivity [HRR], Cross-Borehole Seismography [XBS], Cross-Borehole Radar [XBR], and Cross-Borehole Electromagnetic Induction [CEMI]) to the detection and measurement of Single Shell Tank (SST) leaks into the vadose zone during planned sluicing operations. The testing in FY 2001 will result in the selection of up to two methods for further testing in FY 2002. In parallel with the geophysical tests, a Partitioning Interwell Tracer Test (PITT) study will be conducted simultaneously at the Mock Tank to assess the effectiveness of this technology in detecting and quantifying tank leaks in the vadose zone. Preparatory and background work using Cone Penetrometer methods (CPT) will be conducted at the Mock Tank site and an adjacent test area to derive soil properties for groundtruthing purposes for all methods.
International Nuclear Information System (INIS)
Douglas, D.G.; Maresca, J.W. Jr.
1993-03-01
This document provides a detailed leak detection test plan and schedule for leak testing many of the tanks that comprise the active portion of the liquid low-level waste (LLLW) system at the Oak Ridge National Laboratory (ORNL). This plan was prepared in response to the requirements of the Federal Facility Agreement (FFA) between the US Department of Energy (DOE) and two other agencies, the US Environmental Protection Agency (EPA) and the Tennessee Department of Environment and Conservation (TDEC)
Generazio, Edward R.
2011-01-01
The capability of an inspection system is established by applications of various methodologies to determine the probability of detection (POD). One accepted metric of an adequate inspection system is that for a minimum flaw size and all greater flaw sizes, there is 0.90 probability of detection with 95% confidence (90/95 POD). Directed design of experiments for probability of detection (DOEPOD) has been developed to provide an efficient and accurate methodology that yields estimates of POD and confidence bounds for both Hit-Miss or signal amplitude testing, where signal amplitudes are reduced to Hit-Miss by using a signal threshold Directed DOEPOD uses a nonparametric approach for the analysis or inspection data that does require any assumptions about the particular functional form of a POD function. The DOEPOD procedure identifies, for a given sample set whether or not the minimum requirement of 0.90 probability of detection with 95% confidence is demonstrated for a minimum flaw size and for all greater flaw sizes (90/95 POD). The DOEPOD procedures are sequentially executed in order to minimize the number of samples needed to demonstrate that there is a 90/95 POD lower confidence bound at a given flaw size and that the POD is monotonic for flaw sizes exceeding that 90/95 POD flaw size. The conservativeness of the DOEPOD methodology results is discussed. Validated guidelines for binomial estimation of POD for fracture critical inspection are established.
Directory of Open Access Journals (Sweden)
Freddie Bwanga
Full Text Available The most common method for detection of drug resistant (DR TB in resource-limited settings (RLSs is indirect susceptibility testing on Lowenstein-Jensen medium (LJ which is very time consuming with results available only after 2-3 months. Effective therapy of DR TB is therefore markedly delayed and patients can transmit resistant strains. Rapid and accurate tests suitable for RLSs in the diagnosis of DR TB are thus highly needed. In this study we compared two direct techniques--Nitrate Reductase Assay (NRA and Microscopic Observation Drug Susceptibility (MODS for rapid detection of MDR-TB in a high burden RLS. The sensitivity, specificity, and proportion of interpretable results were studied. Smear positive sputum was collected from 245 consecutive re-treatment TB patients attending a TB clinic in Kampala, Uganda. Samples were processed at the national reference laboratory and tested for susceptibility to rifampicin and isoniazid with direct NRA, direct MODS and the indirect LJ proportion method as reference. A total of 229 specimens were confirmed as M. tuberculosis, of these interpretable results were obtained in 217 (95% with either the NRA or MODS. Sensitivity, specificity and kappa agreement for MDR-TB diagnosis was 97%, 98% and 0.93 with the NRA; and 87%, 95% and 0.78 with the MODS, respectively. The median time to results was 10, 7 and 64 days with NRA, MODS and the reference technique, respectively. The cost of laboratory supplies per sample was low, around 5 USD, for the rapid tests. The direct NRA and MODS offered rapid detection of resistance almost eight weeks earlier than with the reference method. In the study settings, the direct NRA was highly sensitive and specific. We consider it to have a strong potential for timely detection of MDR-TB in RLS.
Comet assay in the detection of irradiated garlic; Teste do cometa na deteccao de alho irradiado
Energy Technology Data Exchange (ETDEWEB)
Villavicencio, Anna Lucia C.H.; Marin-Huachaca, Nelida Simona; Romanelli, Maria Fernanda [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: villavic@net.ipen.br; Delincee, Henry [Federal Research Centre for Nutrition - BFE, Karlsruhe (Germany)]. E-mail: henry.delincee@bfe.uni-karlsruhe.de
2002-07-01
The increased claim for fresh produce has forced a consensus between nations to pay more attention to the phytosanitary regulations. Inhibition of sprouting of bulbs and tubers by applying ionising radiation is authorised by the National Food Codes in Brazil. The availability of methods for detection of irradiated food will contribute to increase consumers' confidence. A quick and simple screening test to indicate whether a food product has been irradiated or not was utilised in this study. The DNA comet assay was applied to verify whether garlic imported from China had been irradiated or not. This test has already been adopted as a European Standard (EN 13784), for detection of irradiated food. Non-irradiated control samples of garlic and garlic treated with maleic hydrazide were compared with garlic samples irradiated in our department. The unirradiated samples exhibited only limited DNA migration. If samples were irradiated, an increased DNA fragmentation was observed which permitted the discrimination between non-irradiated and irradiated samples. Since the garlic samples from China showed only very limited DNA fragmentation, they were deemed non-irradiated. Thus, this simple screening test was shown to be successful for identification of an irradiation treatment. (author)
The Papanicolaou test for cervical cancer detection. A triumph and a tragedy.
Koss, L G
1989-02-03
The complex detection system leading to the discovery and treatment of precancerous lesions and early cancer of the uterine cervix is described in detail and discussed. By far the most difficult and underestimated component of this system is the screening and interpretation of cervical (Papanicolaou) smears. Cytologic case finding may fail because of inadequate samples, insufficient time devoted to screening, or human fatigue. Other weak points of the system, such as an inadequate clinical component, inadequate patient compliance, poor reproducibility of diagnoses, and ineffective aftercare, are also described. For example, obtaining a second smear to confirm or refute a diagnosis of cellular atypia is often a misleading practice. Although this cancer detection system has been shown to be effective in reducing the rate of morbidity and mortality from invasive cervical cancer in appropriately screened populations, there is no evidence that the Papanicolaou test has succeeded anywhere in complete eradication of this theoretically preventable disease. It is important to inform the public about the potential failures of the system and the reasons for them.
Testing of defects in Si semiconductor apparatus by using single-photon detection
International Nuclear Information System (INIS)
Zhongliang, Pan; Ling, Chen; Guangju, Chen
2013-01-01
The failure analysis of semiconductor apparatus is very needed for ensuring product quality, which can find several types of defects in the semiconductor apparatus. A new testing method for the defects in Si semiconductor apparatus is presented in this paper, the method makes use of photon emissions to find out the failure positions or failure components by taking advantage of the infrared photo emission characteristics of semiconductor apparatus. These emitted photons carry the information of the apparatus structure. If there are defects in the apparatus, these photons can help in understanding the apparatus properties and detecting the defects. An algorithm for the generation of circuit input vectors are presented in this paper to enhance the strength of the emitted photons for the given components in the semiconductor apparatus. The multiple-valued logic, the static timing analysis and path sensitizations, are used in the algorithm. A lot of experimental results for the Si semiconductor apparatus show that many types of defects such as contact spiking and latchup failure etc., can be detected accurately by the method proposed in this paper
International Nuclear Information System (INIS)
Aoyama, Takafumi; Ito, Chikara; Harano, Hideki; Okazaki, Koki; Watanabe, Kenichi; Iguchi, Tetsuo
2009-01-01
In a sodium-cooled fast reactor, highly sensitive technology is required to detect small amounts of sodium leaking from the cooling system piping or components. The conventional sodium leak detectors have a fundamental difficulty in improving the detection sensitivity for a sodium leak because of the presence of salinity ( 23 NaCl) in the atmosphere around the components and piping of cooling systems. In order to overcome this problem, an innovative technology has been developed to selectively detect the radioactive sodium ( 22 Na) produced by a neutron reaction in the primary cooling system using Laser Resonance Ionization Mass Spectrometry (RIMS). In this method, sodium ions produced with the two processes of (1) atomization of sodium aerosols and (2) resonance ionization of sodium atom, are detected selectively using a time-of-flight mass spectrometer. The 22 Na can be distinguished from the stable isotope ( 23 Na) by mass spectrometry, which is the advantage of RIMS comparing to the other methods. The design and the construction of the prototype system based on fundamental experiments are shown in the paper. The aerodynamic lens was newly introduced, which can transfer aerosols at atmospheric pressure into a vacuum chamber while increasing the aerosol density at the same time. Furthermore, the ionization process was applied by using the external electric field after resonance exciting from the ground level to the Rydberg level in order to increase the ionization efficiency. The preliminary test results using the stable isotope ( 23 Na) showed that prototype system could easily detect sodium aerosol of 100 ppb, equivalent to the sensitivity of the conventional detectors. (author)
System tuning and measurement error detection testing
International Nuclear Information System (INIS)
Krejci, Petr; Machek, Jindrich
2008-09-01
The project includes the use of the PEANO (Process Evaluation and Analysis by Neural Operators) system to verify the monitoring of the status of dependent measurements with a view to early measurement fault detection and estimation of selected signal levels. At the present stage, the system's capabilities of detecting measurement errors was assessed and the quality of the estimates was evaluated for various system configurations and the formation of empiric models, and rules were sought for system training at chosen process data recording parameters and operating modes. The aim was to find a suitable system configuration and to document the quality of the tuned system on artificial failures
Energy Technology Data Exchange (ETDEWEB)
Bellon, M.S. [Royal Adelaide Hospital, SA (Australia). Dept of Nuclear Medicine
1998-03-01
Full text: Helicobacter pylori infection of the gastric mucosa causes active chronic gastritis and peptic ulceration. Carbon-14 urea breath testing has been well documented in its ability to detect the presence of H. pylori. The aims of this study were to evaluate and refine the test to substantially reduce costs and improve its simplicity, availability and accuracy. We reviewed the results of 138 patients who underwent {sup 14}C urea breath testing for the detection of H. pylori utilising a kit developed at the Royal Adelaide Hospital. Modifications to the standard technique that were assessed included the relevance of buccal cleansing, single sample v multiple sampling, use of alternative CO{sub 2} absorbers and sampling techniques. In those patients with positive biopsy results, a test sensitivity of 100% was achieved. No buccal cleansing is necessary (45% oral contamination without brushing teeth v 41% with). A single breath sample only at 15 min resulted in 100% sensitivity. Alternative (cheaper and safer) CO{sub 2} absorbers such as KOH can be used. Based on these results, modifications to this well documented test have enabled us to substantially reduce costs, improve simplicity and safety and increase accuracy and availability of the test for the detection of Helicobacter pylori.
International Nuclear Information System (INIS)
Zheng Bin; Gur, David; Good, Walter F.; Hardesty, Lara A.
2004-01-01
The purpose of this study is to develop a new method for assessment of the reproducibility of computer-aided detection (CAD) schemes for digitized mammograms and to evaluate the possibility of using the implemented approach for improving CAD performance. Two thousand digitized mammograms (representing 500 cases) with 300 depicted verified masses were selected in the study. Series of images were generated for each digitized image by resampling after a series of slight image rotations. A CAD scheme developed in our laboratory was applied to all images to detect suspicious mass regions. We evaluated the reproducibility of the scheme using the detection sensitivity and false-positive rates for the original and resampled images. We also explored the possibility of improving CAD performance using three methods of combining results from the original and resampled images, including simple grouping, averaging output scores, and averaging output scores after grouping. The CAD scheme generated a detection score (from 0 to 1) for each identified suspicious region. A region with a detection score >0.5 was considered as positive. The CAD scheme detected 238 masses (79.3% case-based sensitivity) and identified 1093 false-positive regions (average 0.55 per image) in the original image dataset. In eleven repeated tests using original and ten sets of rotated and resampled images, the scheme detected a maximum of 271 masses and identified as many as 2359 false-positive regions. Two hundred and eighteen masses (80.4%) and 618 false-positive regions (26.2%) were detected in all 11 sets of images. Combining detection results improved reproducibility and the overall CAD performance. In the range of an average false-positive detection rate between 0.5 and 1 per image, the sensitivity of the scheme could be increased approximately 5% after averaging the scores of the regions detected in at least four images. At low false-positive rate (e.g., ≤average 0.3 per image), the grouping method
Ten years experience of isotopic breath test with special reference to Helicobacter pylori detection
Energy Technology Data Exchange (ETDEWEB)
Verhas, M.; Tricht, L.Van; Verschaeren, A.; Delmotte, E.; Martin, P
1997-12-31
The use of the carbon 14 urea breath test by comparison with culture for campylobacter of gastric endoscopic biopsies is studied in 91 patients. They were divided into 2 groups. The first group consisted of 53 patients examined by gastric endoscopy and carbon 14 urea breath test. In this population, gastric biopsies were taken at different regions of the stomach and duodenum. The breath test was performed within 3 hours after endoscopy. The second group consisted of 38 asymptomatic patients whom 23 were parent of children with campylobacter positive gastritis. For the whole population, neither antibiotic therapy nor bismuth medication was administrated within the 15 days before the realization of the test. Results were expressed in % of injected dose/mmole of CO{sub 2} after correction of endogenous production of CO{sub 2}. In conclusion, carbon 14 urea breath test is a reliable noninvasive test for detection and follow-up of gastritis caused by a widespread microorganism. Also, the precision of both tests, {sup 14} C-UBT and {sup 13} C-UBT, are compared simultaneously in 84 adults patients. The results were expressed as % of administered dose expired in 30 minutes. A better precision is observed with the {sup 13} C-UBT
Directory of Open Access Journals (Sweden)
Sylvia Worbs
2015-11-01
Full Text Available In the framework of the EU project EQuATox, a first international proficiency test (PT on the detection and quantification of botulinum neurotoxins (BoNT was conducted. Sample materials included BoNT serotypes A, B and E spiked into buffer, milk, meat extract and serum. Different methods were applied by the participants combining different principles of detection, identification and quantification. Based on qualitative assays, 95% of all results reported were correct. Successful strategies for BoNT detection were based on a combination of complementary immunological, MS-based and functional methods or on suitable functional in vivo/in vitro approaches (mouse bioassay, hemidiaphragm assay and Endopep-MS assay. Quantification of BoNT/A, BoNT/B and BoNT/E was performed by 48% of participating laboratories. It turned out that precise quantification of BoNT was difficult, resulting in a substantial scatter of quantitative data. This was especially true for results obtained by the mouse bioassay which is currently considered as “gold standard” for BoNT detection. The results clearly demonstrate the urgent need for certified BoNT reference materials and the development of methods replacing animal testing. In this context, the BoNT PT provided the valuable information that both the Endopep-MS assay and the hemidiaphragm assay delivered quantitative results superior to the mouse bioassay.
Cambau, Emmanuelle; Allerheiligen, Vera; Coulon, Céline; Corbel, Céline; Lascols, Christine; Deforges, Lionel; Soussy, Claude-James; Delchier, Jean-Charles; Megraud, Francis
2009-11-01
The eradication rate of Helicobacter pylori by standard therapy is decreasing due to antibiotic resistance, mainly to clarithromycin. Our aim was to provide a new molecular test to guide the treatment of new and relapsed cases. We first studied 126 H. pylori strains for phenotypic (MIC) and genotypic resistance to clarithromycin (rrl mutation) and levofloxacin (gyrA mutation) and then developed a DNA strip genotyping test on the basis of the correlation results and literature data. Clinical strains (n = 92) and gastric biopsy specimens containing H. pylori (n = 105) were tested blindly with the new molecular test GenoType HelicoDR. The presence of mutations or the absence of hybridization with wild-type sequences was predictive, in rrl for clarithromycin resistance in 91 cases (mostly the A2147G mutation) and in gyrA for levofloxacin resistance in 58 cases (mutations at codon 87 or 91). Genotyping revealed a mix of genotypes in 33% of the cases, reflecting a coinfection or selection for resistant mutants. The sensitivity and specificity of detecting resistance were 94% and 99% for clarithromycin and 87% and 98.5% for levofloxacin, respectively. The concordance scores were 0.96 for clarithromycin and 0.94 for levofloxacin. With global resistance rates of 46% for clarithromycin and 25% for levofloxacin, which were observed for consecutive positive biopsy specimens from 2007 and 2008, the positive and negative predictive values for detecting resistance were 99% and 94% for clarithromycin and 96% and 96% for fluoroquinolone. GenoType HelicoDR is efficient at detecting mutations predictive of antibiotic resistance in H. pylori when applied to strains or directly to gastric biopsy specimens.
Directory of Open Access Journals (Sweden)
Gilbert G. G. Donders
2010-01-01
Full Text Available Accessing vaginal pH is fundamental during gynaecological visit for the detection of abnormal vaginal flora (AVF, but use of pH strips may be time-consuming and difficult to interpret. The aim of this study was to evaluate the VS-SENSE test (Common Sense Ltd, Caesarea, Israel as a tool for the diagnosis of AVF and its correlation with abnormal pH and bacterial vaginosis (BV. The study population consisted of 45 women with vaginal pH ≥ 4.5 and 45 women with normal pH. Vaginal samples were evaluated by VS-SENSE test, microscopy and microbiologic cultures. Comparing with pH strips results, VS-SENSE test specificity was 97.8% and sensitivity of 91%. All severe cases of BV and aerobic vaginitis (AV were detected by the test. Only one case with normal pH had an unclear result. Concluding, VS-SENSE test is easy to perform, and it correlates with increased pH, AVF, and the severe cases of BV and AV.
Testing seismic amplitude source location for fast debris-flow detection at Illgraben, Switzerland
Walter, Fabian; Burtin, Arnaud; McArdell, Brian W.; Hovius, Niels; Weder, Bianca; Turowski, Jens M.
2017-06-01
Heavy precipitation can mobilize tens to hundreds of thousands of cubic meters of sediment in steep Alpine torrents in a short time. The resulting debris flows (mixtures of water, sediment and boulders) move downstream with velocities of several meters per second and have a high destruction potential. Warning protocols for affected communities rely on raising awareness about the debris-flow threat, precipitation monitoring and rapid detection methods. The latter, in particular, is a challenge because debris-flow-prone torrents have their catchments in steep and inaccessible terrain, where instrumentation is difficult to install and maintain. Here we test amplitude source location (ASL) as a processing scheme for seismic network data for early warning purposes. We use debris-flow and noise seismograms from the Illgraben catchment, Switzerland, a torrent system which produces several debris-flow events per year. Automatic in situ detection is currently based on geophones mounted on concrete check dams and radar stage sensors suspended above the channel. The ASL approach has the advantage that it uses seismometers, which can be installed at more accessible locations where a stable connection to mobile phone networks is available for data communication. Our ASL processing uses time-averaged ground vibration amplitudes to estimate the location of the debris-flow front. Applied to continuous data streams, inversion of the seismic amplitude decay throughout the network is robust and efficient, requires no manual identification of seismic phase arrivals and eliminates the need for a local seismic velocity model. We apply the ASL technique to a small debris-flow event on 19 July 2011, which was captured with a temporary seismic monitoring network. The processing rapidly detects the debris-flow event half an hour before arrival at the outlet of the torrent and several minutes before detection by the in situ alarm system. An analysis of continuous seismic records furthermore
Testing seismic amplitude source location for fast debris-flow detection at Illgraben, Switzerland
Directory of Open Access Journals (Sweden)
F. Walter
2017-06-01
Full Text Available Heavy precipitation can mobilize tens to hundreds of thousands of cubic meters of sediment in steep Alpine torrents in a short time. The resulting debris flows (mixtures of water, sediment and boulders move downstream with velocities of several meters per second and have a high destruction potential. Warning protocols for affected communities rely on raising awareness about the debris-flow threat, precipitation monitoring and rapid detection methods. The latter, in particular, is a challenge because debris-flow-prone torrents have their catchments in steep and inaccessible terrain, where instrumentation is difficult to install and maintain. Here we test amplitude source location (ASL as a processing scheme for seismic network data for early warning purposes. We use debris-flow and noise seismograms from the Illgraben catchment, Switzerland, a torrent system which produces several debris-flow events per year. Automatic in situ detection is currently based on geophones mounted on concrete check dams and radar stage sensors suspended above the channel. The ASL approach has the advantage that it uses seismometers, which can be installed at more accessible locations where a stable connection to mobile phone networks is available for data communication. Our ASL processing uses time-averaged ground vibration amplitudes to estimate the location of the debris-flow front. Applied to continuous data streams, inversion of the seismic amplitude decay throughout the network is robust and efficient, requires no manual identification of seismic phase arrivals and eliminates the need for a local seismic velocity model. We apply the ASL technique to a small debris-flow event on 19 July 2011, which was captured with a temporary seismic monitoring network. The processing rapidly detects the debris-flow event half an hour before arrival at the outlet of the torrent and several minutes before detection by the in situ alarm system. An analysis of continuous seismic
Laser Spot Center Detection and Comparison Test
Zhu, Jun; Xu, Zhengjie; Fu, Deli; Hu, Cong
2018-04-01
High efficiency and precision of the pot center detection are the foundations of avionics instrument navigation and optics measurement basis for many applications. It has noticeable impact on overall system performance. Among them, laser spot detection is very important in the optical measurement technology. In order to improve the low accuracy of the spot center position, the algorithm is improved on the basis of the circle fitting. The pretreatment is used by circle fitting, and the improved adaptive denoising filter for TV repair technology can effectively improves the accuracy of the spot center position. At the same time, the pretreatment and de-noising can effectively reduce the influence of Gaussian white noise, which enhances the anti-jamming capability.
Van Strien, Jan W.; Franken, Ingmar H. A.; Huijding, Jorg
2014-01-01
According to the snake detection hypothesis (Isbell, 2006), fear specifically of snakes may have pushed evolutionary changes in the primate visual system allowing pre-attentional visual detection of fearful stimuli. A previous study demonstrated that snake pictures, when compared to spiders or bird pictures, draw more early attention as reflected by larger early posterior negativity (EPN). Here we report two studies that further tested the snake detection hypothesis. In Study, 1 we tested whe...
Imbers, J.; Lopez, A.; Huntingford, C.; Allen, M. R.
2013-01-01
This paper aims to test the robustness of the detection and attribution of anthropogenic climate change using four different empirical models that were previously developed to explain the observed global mean temperature changes over the last few decades. These studies postulated that the main drivers of these changes included not only the usual natural forcings, such as solar and volcanic, and anthropogenic forcings, such as greenhouse gases and sulfates, but also other known Earth system oscillations such as El Niño Southern Oscillation (ENSO) or the Atlantic Multidecadal Oscillation (AMO). In this paper, we consider these signals, or forced responses, and test whether or not the anthropogenic signal can be robustly detected under different assumptions for the internal variability of the climate system. We assume that the internal variability of the global mean surface temperature can be described by simple stochastic models that explore a wide range of plausible temporal autocorrelations, ranging from short memory processes exemplified by an AR(1) model to long memory processes, represented by a fractional differenced model. In all instances, we conclude that human-induced changes to atmospheric gas composition is affecting global mean surface temperature changes. ©2013. American Geophysical Union. All Rights Reserved.
Imbers, J.
2013-04-27
This paper aims to test the robustness of the detection and attribution of anthropogenic climate change using four different empirical models that were previously developed to explain the observed global mean temperature changes over the last few decades. These studies postulated that the main drivers of these changes included not only the usual natural forcings, such as solar and volcanic, and anthropogenic forcings, such as greenhouse gases and sulfates, but also other known Earth system oscillations such as El Niño Southern Oscillation (ENSO) or the Atlantic Multidecadal Oscillation (AMO). In this paper, we consider these signals, or forced responses, and test whether or not the anthropogenic signal can be robustly detected under different assumptions for the internal variability of the climate system. We assume that the internal variability of the global mean surface temperature can be described by simple stochastic models that explore a wide range of plausible temporal autocorrelations, ranging from short memory processes exemplified by an AR(1) model to long memory processes, represented by a fractional differenced model. In all instances, we conclude that human-induced changes to atmospheric gas composition is affecting global mean surface temperature changes. ©2013. American Geophysical Union. All Rights Reserved.
Directory of Open Access Journals (Sweden)
Jinqi Zhao
2017-12-01
Full Text Available In recent years, multi-temporal imagery from spaceborne sensors has provided a fast and practical means for surveying and assessing changes in terrain surfaces. Owing to the all-weather imaging capability, polarimetric synthetic aperture radar (PolSAR has become a key tool for change detection. Change detection methods include both unsupervised and supervised methods. Supervised change detection, which needs some human intervention, is generally ineffective and impractical. Due to this limitation, unsupervised methods are widely used in change detection. The traditional unsupervised methods only use a part of the polarization information, and the required thresholding algorithms are independent of the multi-temporal data, which results in the change detection map being ineffective and inaccurate. To solve these problems, a novel method of change detection using a test statistic based on the likelihood ratio test and the improved Kittler and Illingworth (K&I minimum-error thresholding algorithm is introduced in this paper. The test statistic is used to generate the comparison image (CI of the multi-temporal PolSAR images, and improved K&I using a generalized Gaussian model simulates the distribution of the CI. As a result of these advantages, we can obtain the change detection map using an optimum threshold. The efficiency of the proposed method is demonstrated by the use of multi-temporal PolSAR images acquired by RADARSAT-2 over Wuhan, China. The experimental results show that the proposed method is effective and highly accurate.
DEFF Research Database (Denmark)
Nielsen, Søren Saxmose; Toft, Nils
2014-01-01
Detection of bulk tank milk (BTM) antibodies using ELISA (BTM-ELISA) may constitute an inexpensive test for surveillance of Mycobacterium avium subsp. paratuberculosis (MAP) infection in dairy cattle herds provided that the test is accurate and consistent. The objectives of this study were...... Danish Holstein herds over a period of one year. All samples were tested using a commercial indirect ELISA for detection of MAP specific antibodies. The individual cow's results were dichotomised and used to estimate the within-herd antibody prevalence at each test-date. These prevalences were...... to 0.60 when corrected for the within-herd antibody prevalence. Although the test-results were relatively consistent and correlated with the within-herd prevalence, the magnitude of the test-values makes it difficult to use the BTM-ELISA for surveillance of MAP infections in practice....
Energy Technology Data Exchange (ETDEWEB)
Casali, P; Bossus, A; Carpentier, N A; Lambert, P H [Hopital Cantonal Geneve (Switzerland)
1977-01-01
Bovine conglutinin was used in a solid-phase assay for the detection of immune complexes. In a first step, the tested serum sample was incubated in polypropylene tubes coated with conglutinin to allow C3-coated immune complexes to bind to solid-phase conglutinin. In a second step, the conglutinin-bound complexes were detected using an enzyme-conjugated or radiolabelled anti-immunoglobulin antibody. The conglutinin-binding (KgB) test did not suffer from the interference of DNA, heparin or endotoxins. Its limit of sensitivity for aggregated IgG was 3 ..mu..g/ml undiluted human serum. Immune complexes prepared in vitro using tetanus toxoid, or DNA, and corresponding antibodies in human sera could be detected at various antigen/antibody ratios and at antibody concentrations lower than 8 ..mu..g/ml. The KgB test allowed for the detection of immune complexes in sera from patients with systemic lupus erythematosus, rheumatoid arthritis, idiopathic vasculitis, leprosy and leukemia. These sera were also tested using the /sup 125/I-labelled Clq-binding activity (BA) test and the KgB test simultaneously, and a significant rank order correlation was observed. In patients with leukemia, a significant correlation was observed using three tests, KgB, /sup 125/I-labelled Clq BA and Raji-cell radioimmunoassay (RIA). Therefore, the KgB test appears as a simple and reproducible method, utilizing a very stable reagent, with a sensitivity and specificity comparable to the other tests studied and allowing for clinical application.
Sato, Junko; Ishii, Yoshinori; Noguchi, Hideo
2016-01-01
The extensor carpi ulnaris (ECU) tendon synergy test is a simple and unique diagnostic maneuver for evaluation of chronic dorsal ulnar-sided wrist pain, which applies isolated tension to the ECU without greatly stressing other structures. This study aimed to investigate the diagnostic performance of the ECU synergy test to detect ECU abnormalities on sonography. Forty affected wrists from 39 consecutive patients with chronic dorsal ulnar-sided wrist pain that continued for greater than 1 month were examined with the ECU synergy test and sonography. The sensitivity, specificity, positive predictive value, and negative predictive value of the ECU synergy test to detect ECU abnormalities were evaluated. We compared the results of the ECU synergy test between groups with and without ECU abnormalities and also compared the ages, sexes, and symptomatic durations of the patients between groups with positive and negative ECU synergy test results and between the groups with and without ECU abnormalities. The sensitivity, specificity, positive predictive value, and negative predictive value were 73.7%, 85.7%, 82.4%, and 78.3%, respectively. There was significant difference in the ECU synergy test results between the groups with and without ECU abnormalities (P synergy test could be a useful provocative maneuver to detect ECU abnormalities in patients with chronic dorsal ulnar-sided wrist pain. © 2016 by the American Institute of Ultrasound in Medicine.
Singh, Manju; Singh, Shoor Vir; Gupta, Saurabh; Chaubey, Kundan Kumar; Stephan, Bjorn John; Sohal, Jagdip Singh; Dutta, Manali
2018-04-26
Early rapid detection of Mycobacterium avium subspecies paratuberculosis (MAP) bacilli in milk samples is the major challenge since traditional culture method is time consuming and laboratory dependent. We report a simple, sensitive and specific nano-technology based 'Nano-immuno test' capable of detecting viable MAP bacilli in the milk samples within 10 h. Viable MAP bacilli were captured by MAP specific antibody-conjugated magnetic nano-particles using resazurin dye as chromogen. Test was optimized using true culture positive (10-bovine and 12-goats) and true culture negative (16-bovine and 25-goats) raw milk samples. Domestic livestock species in India are endemically infected with MAP. After successful optimization, sensitivity and specificity of the 'nano-immuno test' in goats with respect to milk culture was 91.7% and 96.0%, respectively. Whereas, it was 90.0% (sensitivity) and 92.6% (specificity) with respect to IS900 PCR. In bovine milk samples, sensitivity and specificity of 'nano-immuno test' with respect to milk culture was 90.0% and 93.7%, respectively. However, with respect to IS900 PCR, the sensitivity and specificity was 88.9% and 94.1%, respectively. Test was validated with field raw milk samples (goats-258 and bovine-138) collected from domestic livestock species to detect live/viable MAP bacilli. Of 138 bovine raw milk samples screened by six diagnostic tests, 81 (58.7%) milk samples were positive for MAP infection in one or more than one diagnostic tests. Of 81 (58.7%) positive bovine raw milk samples, only 24 (17.4%) samples were detected positive for the presence of viable MAP bacilli. Of 258 goats raw milk samples screened by six diagnostic tests, 141 (54.6%) were positive for MAP infection in one or more than one test. Of 141 (54.6%) positive raw milk samples from goats, only 48 (34.0%) were detected positive for live MAP bacilli. Simplicity and efficiency of this novel 'nano-immuno test' makes it suitable for wide-scale screening of milk
Chen, I.-H.; Horikawa, S.; Xi, J.; Wikle, H. C.; Barbaree, J. M.; Chin, B. A.
2017-05-01
Phage based magneto-elastic (ME) biosensors have been shown to be able to rapidly detect Salmonella in various food systems to serve food pathogen monitoring purposes. In this ME biosensor platform, the free-standing strip-shaped magneto-elastic sensor is the transducer and the phage probe that recognizes Salmonella in food serves as the bio-recognition element. According to Sorokulova et al. at 2005, a developed oligonucleotide probe E2 was reported to have high specificity to Salmonella enterica Typhimurium. In the report, the specificity tests were focused in most of Enterobacterace groups outside of Salmonella family. Here, to understand the specificity of phage E2 to different Salmonella enterica serotypes within Salmonella Family, we further tested the specificity of the phage probe to thirty-two Salmonella serotypes that were present in the major foodborne outbreaks during the past ten years (according to Centers for Disease Control and Prevention). The tests were conducted through an Enzyme linked Immunosorbent Assay (ELISA) format. This assay can mimic probe immobilized conditions on the magnetoelastic biosensor platform and also enable to study the binding specificity of oligonucleotide probes toward different Salmonella while avoiding phage/ sensor lot variations. Test results confirmed that this oligonucleotide probe E2 was high specific to Salmonella Typhimurium cells but showed cross reactivity to Salmonella Tennessee and four other serotypes among the thirty-two tested Salmonella serotypes.
A blind test of nondestructive underground void detection by ground penetrating radar (GPR)
Lai, Wallace W. L.; Chang, Ray K. W.; Sham, Janet F. C.
2018-02-01
Blind test/experiment is widely adopted in various scientific disciplines like medicine drug testing/clinical trials/psychology, but not popular in nondestructive testing and evaluation (NDTE) nor near-surface geophysics (NSG). This paper introduces a blind test of nondestructive underground void detection in highway/pavement using ground penetrating radar (GPR). Purpose of which is to help the Highways Department (HyD) of the Hong Kong Government to evaluate the feasibility of large-scale and nationwide application, and examine the ability of appropriate service providers to carry out such works. In the past failure case of such NDTE/NSG based on lowest bid price, it is not easy to know which part(s) in SWIMS (S - service provider, i.e. people; W - work procedure; I - instrumentation; M - materials in the complex underground; S - specifications by client) fails, and how it/they fail(s). This work attempts to carry out the blind test by burying fit balls (as voids) under a site with reinforced concrete road and paving block by PolyU team A. The blind test about the void centroid, spread and cover depth was then carried out by PolyU team B without prior information given. Then with this baseline, a marking scheme, acceptance criteria and passing mark were set to test six local commercial service providers, determine their scores and evaluate the performance. A pass is a prerequisite of the award of a service contract of similar nature. In this first attempt of the blind test, results were not satisfactory and it is concluded that 'S-service provider' and 'W-work procedure' amongst SWIMS contributed to most part of the unsatisfactory performance.+
Zhang, Bin; Qian, Yao; Wu, Yuntian; Yang, Y. B.
2018-04-01
To further the technique of indirect measurement, the contact-point response of a moving test vehicle is adopted for the damage detection of bridges. First, the contact-point response of the vehicle moving over the bridge is derived both analytically and in central difference form (for field use). Then, the instantaneous amplitude squared (IAS) of the driving component of the contact-point response is calculated by the Hilbert transform, making use of its narrow-band feature. The IAS peaks serve as the key parameter for damage detection. In the numerical simulation, a damage (crack) is modeled by a hinge-spring unit. The feasibility of the proposed method to detect the location and severity of a damage or multi damages of the bridge is verified. Also, the effects of surface roughness, vehicle speed, measurement noise and random traffic are studied. In the presence of ongoing traffic, the damages of the bridge are identified from the repeated or invariant IAS peaks generated for different traffic flows by the same test vehicle over the bridge.
International Nuclear Information System (INIS)
Florent, C.; Vidon, N.; Flourie, B.; Carmantrand, A.; Zerbani, A.; Maurel, M.; Bernier, J.J.
1986-01-01
Gastric losses of plasma are usually measured with radiolabeled macromolecules. This method is expensive and cumbersome. Direct measurement of exudated plasma proteins are ineffective since proteins are denaturated by acidic gastric juice and pepsin. It was recently shown that albumin measurement after immediate neutralization allowed detection of gastric protein losses, but this method is quite complex and time consuming. We studied alpha 1-antitrypsin and 51Cr-labeled protein clearance in gastric juice during normal saline and cimetidine (1.5 mg/kg/hr) infusion in six healthy volunteers and six patients with exudative gastropathy. alpha 1-Antitrypsin was measurable in all samples during cimetidine infusion: alpha 1-AT and 51Cr losses were significantly correlated (P less than 0.001). The upper limit of gastric alpha 1-AT clearance in controls was 0.86 ml/hr (mean + 2 SD). Using this value, there was no overlapping between patients and controls. The upper limit of 51Cr test was 1.87 ml/hr (mean + 2 SD) in controls but gastric clearance of 51Cr was below this value in one patient. This suggests that the measurement of alpha 1-AT gastric clearance during cimetidine perfusion is a good test to detect an exudative gastropathy. This test is inexpensive and lasts only 3 hr
Measurement of EPF for detection of cow pregnancy using rosette inhibition test.
Ghaffari Laleh, V; Ghaffari Laleh, R; Pirany, N; Moghadaszadeh Ahrabi, M
2008-07-01
Early embryonic death of calves due to sub-fertility in cows is of great economic concern to dairy industry. Early pregnancy factor (EPF) is a secretory protein with pregnancy associated immunosuppressive properties. Rosette inhibition test (RIT) was used to detect EPF in inseminated dairy cows. Blood samples were collected at two intervals, 1-3 and 5-7 days after insemination from 23 inseminated and 18 non-inseminated control cows for RIT and pregnancy diagnosis performed between 42 and 45 days on palpation. The study indicates that RIT (P<0.05) has the potential to distinguish pregnant from non-pregnant dairy cows in the first week of pregnancy.
Yunus, Sami; Massart, Marion; Huang, Te-Din; Glupczynski, Youri
2015-01-01
Accurate detection of carbapenemase-producing Enterobacteriaceae (CPE) constitutes a major laboratory diagnostic challenge. We evaluated an electrochemical technique (the BYG Carba test) which allows detection of CPE in less than 35 min. The BYG Carba test was first validated in triplicate against 57 collection isolates with previously characterized β-lactam resistance mechanisms (OXA-48, n = 12; KPC, n = 8; NDM, n = 8; VIM, n = 8; IMP, n = 3; GIM, n = 1; GES-6, n = 1; no carbapenemase, n = 16) and against a panel of 10 isolates obtained from the United Kingdom National External Quality Assessment Service (NEQAS). The test was then evaluated prospectively against 324 isolates referred to the national reference center for suspicion of CPE. The BYG Carba test results were compared with those obtained with the Carba NP test using multiplex PCR sequencing as the gold standard. Of the 57 collection and the 10 NEQAS isolates, all but one GES-6-producing isolate were correctly identified by the Carba BYG test. Among the 324 consecutive Enterobacteriaceae isolates tested prospectively, 146 were confirmed as noncarbapenemase producers by PCR while 178 harbored a carbapenemase gene (OXA-48, n = 117; KPC, n = 25; NDM, n = 23; and VIM, n = 13). Prospectively, in comparison with PCR results, the BYG Carba test displayed 95% sensitivity and 100% specificity versus 89% and 100%, respectively, for the Carba NP test. The BYG Carba test is a novel, rapid, and efficient assay based on an electro-active polymer biosensing technology discriminating between CPE and non-CPE. The precise electrochemical signal (electrochemical impedance variations) allows the establishment of real-time objective measurement and interpretation criteria which should facilitate the accreditation process of this technology. PMID:26637378
Cosmological Non-Gaussian Signature Detection: Comparing Performance of Different Statistical Tests
Directory of Open Access Journals (Sweden)
O. Forni
2005-09-01
Full Text Available Currently, it appears that the best method for non-Gaussianity detection in the cosmic microwave background (CMB consists in calculating the kurtosis of the wavelet coefficients. We know that wavelet-kurtosis outperforms other methods such as the bispectrum, the genus, ridgelet-kurtosis, and curvelet-kurtosis on an empirical basis, but relatively few studies have compared other transform-based statistics, such as extreme values, or more recent tools such as higher criticism (HC, or proposed “best possible†choices for such statistics. In this paper, we consider two models for transform-domain coefficients: (a a power-law model, which seems suited to the wavelet coefficients of simulated cosmic strings, and (b a sparse mixture model, which seems suitable for the curvelet coefficients of filamentary structure. For model (a, if power-law behavior holds with finite 8th moment, excess kurtosis is an asymptotically optimal detector, but if the 8th moment is not finite, a test based on extreme values is asymptotically optimal. For model (b, if the transform coefficients are very sparse, a recent test, higher criticism, is an optimal detector, but if they are dense, kurtosis is an optimal detector. Empirical wavelet coefficients of simulated cosmic strings have power-law character, infinite 8th moment, while curvelet coefficients of the simulated cosmic strings are not very sparse. In all cases, excess kurtosis seems to be an effective test in moderate-resolution imagery.
Trawny, Nikolas; Huertas, Andres; Luna, Michael E.; Villalpando, Carlos Y.; Martin, Keith E.; Carson, John M.; Johnson, Andrew E.; Restrepo, Carolina; Roback, Vincent E.
2015-01-01
The Hazard Detection System (HDS) is a component of the ALHAT (Autonomous Landing and Hazard Avoidance Technology) sensor suite, which together provide a lander Guidance, Navigation and Control (GN&C) system with the relevant measurements necessary to enable safe precision landing under any lighting conditions. The HDS consists of a stand-alone compute element (CE), an Inertial Measurement Unit (IMU), and a gimbaled flash LIDAR sensor that are used, in real-time, to generate a Digital Elevation Map (DEM) of the landing terrain, detect candidate safe landing sites for the vehicle through Hazard Detection (HD), and generate hazard-relative navigation (HRN) measurements used for safe precision landing. Following an extensive ground and helicopter test campaign, ALHAT was integrated onto the Morpheus rocket-powered terrestrial test vehicle in March 2014. Morpheus and ALHAT then performed five successful free flights at the simulated lunar hazard field constructed at the Shuttle Landing Facility (SLF) at Kennedy Space Center, for the first time testing the full system on a lunar-like approach geometry in a relevant dynamic environment. During these flights, the HDS successfully generated DEMs, correctly identified safe landing sites and provided HRN measurements to the vehicle, marking the first autonomous landing of a NASA rocket-powered vehicle in hazardous terrain. This paper provides a brief overview of the HDS architecture and describes its in-flight performance.
Uddameri, Venkatesh; Singaraju, Sreeram; Hernandez, E Annette
2018-02-21
Seasonal and cyclic trends in nutrient concentrations at four agricultural drainage ditches were assessed using a dataset generated from a multivariate, multiscale, multiyear water quality monitoring effort in the agriculturally dominant Lower Rio Grande Valley (LRGV) River Watershed in South Texas. An innovative bootstrap sampling-based power analysis procedure was developed to evaluate the ability of Mann-Whitney and Noether tests to discern trends and to guide future monitoring efforts. The Mann-Whitney U test was able to detect significant changes between summer and winter nutrient concentrations at sites with lower depths and unimpeded flows. Pollutant dilution, non-agricultural loadings, and in-channel flow structures (weirs) masked the effects of seasonality. The detection of cyclical trends using the Noether test was highest in the presence of vegetation mainly for total phosphorus and oxidized nitrogen (nitrite + nitrate) compared to dissolved phosphorus and reduced nitrogen (total Kjeldahl nitrogen-TKN). Prospective power analysis indicated that while increased monitoring can lead to higher statistical power, the effect size (i.e., the total number of trend sequences within a time-series) had a greater influence on the Noether test. Both Mann-Whitney and Noether tests provide complementary information on seasonal and cyclic behavior of pollutant concentrations and are affected by different processes. The results from these statistical tests when evaluated in the context of flow, vegetation, and in-channel hydraulic alterations can help guide future data collection and monitoring efforts. The study highlights the need for long-term monitoring of agricultural drainage ditches to properly discern seasonal and cyclical trends.
Calès, P; Zarski, J P; Chapplain, J Marc; Bertrais, S; Sturm, N; Michelet, C; Babany, G; Chaigneau, J; Eddine Charaf, M
2012-02-01
We evaluated whether quantitative measurements of liver fibrosis with recently developed diagnostics outperform histological staging in detecting natural or interferon-induced changes. We compared Metavir staging, morphometry (area and fractal dimension) and six blood tests in 157 patients with chronic hepatitis C from two trials testing maintenance interferon for 96 weeks. Paired liver biopsies and blood tests were available for 101 patients, and there was a significant improvement in Metavir activity and a significant increase in blood tests reflecting fibrosis quantity in patients treated with interferon when compared with controls - all per cent changes in histological fibrosis measures were significantly increased in F1 vs F2-4 stages only in the interferon group. For the whole population studied between weeks 0 and 96, there was significant progression only in the area of fibrosis (AOF) (P = 0.026), FibroMeter (P = 0.020) and CirrhoMeter (P = 0.003). With regards to dynamic reproducibility, agreement was good (r(ic) ≥ 0.72) only for Metavir fibrosis score, FibroMeter and CirrhoMeter. The per cent change in AOF was significantly higher than that of fractal dimension (P = 0.003) or Metavir fibrosis score (P = 0.015). CirrhoMeter was the only blood test with a change significantly higher than that of AOF (P = 0.039). AOF and two blood tests, reflecting fibrosis quantity, have high sensitivity and/or reproducibility permitting the detection of a small progression in liver fibrosis over two years. A blood test reflecting fibrosis quantity is more sensitive and reproducible than morphometry. The study also shows that maintenance interferon does not improve fibrosis, whatever its stage. © 2011 Blackwell Publishing Ltd.
Yang, Mingming; Zhao, Yuting; Wang, Limin; Paulsen, Michael; Simpson, Christopher D; Liu, Fengquan; Du, Dan; Lin, Yuehe
2018-05-01
A novel sandwich immunoassay based immunochromatographic test strip (ICTS) has been developed for simultaneously measuring both butyrylcholinesterase (BChE) activity and the total amount of BChE (including inhibited and active enzyme) from 70 μLpost-exposure human plasma sample. The principle of this method is based on the BChE monoclonal antibody (MAb) capable of acting as both capture antibody and detection antibody. The BChE MAb which was immobilized on the test line was able to recognize both organophosphorus BChE adducts (OP-BChE) and BChE and provided equal binding affinity, permitting detection of the total enzyme amount in post-exposure human plasma samples. The formed immunocomplexes on the test line can further be excised from the test-strip for subsequent off-line measurement of BChE activity using the Ellman assay. Therefore, dual biomarkers of BChE activity and phosphorylation (OP-BChE) will be obtained simultaneously. The whole sandwich-immunoassay was performed on one ICTS, greatly reducing analytical time. The ICTS sensor showed excellent linear responses for assaying total amount of BChE and active BChE ranging from 0.22 to 3.58nM and 0.22-7.17nM, respectively. Both the signal detection limits are 0.10nM. We validated the practical application of the proposed method to measure 124 human plasma samples from orchard workers and cotton farmers with long-term exposure to organophosphorus pesticides (OPs). The results were in highly agreement with LC/MS/MS which verified our method is extremely accurate. Combining the portability and rapidity of test strip and the compatibility of BChE MAb as both capture antibody and detection antibody, the developed method provides a baseline-free, low-cost and rapid tool for in-field monitoring of OP exposures. Copyright © 2018 Elsevier B.V. All rights reserved.
Mulcahey, M J; Slavin, Mary D; Ni, Pengsheng; Vogel, Lawrence C; Kozin, Scott H; Haley, Stephen M; Jette, Alan M
2015-09-16
The Cerebral Palsy Computerized Adaptive Test (CP-CAT) is a parent-reported outcomes instrument for measuring lower and upper-extremity function, activity, and global health across impairment levels and a broad age range of children with cerebral palsy (CP). This study was performed to examine whether the Lower Extremity/Mobility (LE) CP-CAT detects change in mobility following orthopaedic surgery in children with CP. This multicenter, longitudinal study involved administration of the LE CP-CAT, the Pediatric Outcomes Data Collection Instrument (PODCI) Transfer/Mobility and Sports/Physical Functioning domains, and the Timed "Up & Go" test (TUG) before and after elective orthopaedic surgery in a convenience sample of 255 children, four to twenty years of age, who had CP and a Gross Motor Function Classification System (GMFCS) level of I, II, or III. Standardized response means (SRMs) and 95% confidence intervals (CIs) were calculated for all measures at six, twelve, and twenty-four months following surgery. SRM estimates for the LE CP-CAT were significantly greater than the SRM estimates for the PODCI Transfer/Mobility domain at twelve months, the PODCI Sports/Physical Functioning domain at twelve months, and the TUG at twelve and twenty-four months. When the results for the children at GMFCS levels I, II, and III were grouped together, the improvements in function detected by the LE CP-CAT at twelve and twenty-four months were found to be greater than the changes detected by the PODCI Transfer/Mobility and Sports/Physical Functioning scales. The LE CP-CAT outperformed the PODCI scales for GMFCS levels I and III at both of these follow-up intervals; none of the scales performed well for patients with GMFCS level II. The results of this study showed that the LE CP-CAT displayed superior sensitivity to change than the PODCI and TUG scales after musculoskeletal surgery in children with CP. Copyright © 2015 by The Journal of Bone and Joint Surgery, Incorporated.
Standardization of serological tests for detecting anti-Trypanosoma cruzi antibodies in dogs
Directory of Open Access Journals (Sweden)
M. A. Lauricella
1993-09-01
Full Text Available This paper reports on the standardization of four serological reactions currently used in human serodiagnosis for the detection of anti-Trypanosoma cruzi antibodies in naturally and experimentally infected dogs. Indirect immunofluorescence test (IFAT and hemagglutination test (IHAT were standardized, and complement fixation test (CFT and direct agglutination test (DAT were used for diagnostic confirmation. Four hundred and eighty one mongrel dogs that were studied by xenodiagnosis were used: (1 parasitemic dogs of two localities of endemic area (EA of Santiago del Estero province in Argentina (n = 134; (2 non-parasitemic dogs of the same area (n = 285; (3 dogs experimentally infected with T. cruzi in the patent period (n = 6; (4 non-infected dogs (n = 56 which were born in the city of Buenos Aires (BA, one non-EA for Chagas' disease. For IFAT, parasitemic dogs EA showed 95% of reactive sera. Non parasitemic dogs EA showed 77% of non reactive sera. None sera from BA were reactive for dilutions higher than four. For IHAT, 84% of sera of parasitemic dogs EA showed serological reactivity and among non parasitemic dogs BA, 61% were non reactive, while the remainder showed at most titres of 1/16. The cut-off titres for IFAT and IHAT were 1/16 and 1/32 respectively, and for CFT and DAT 1/1 and 1/128 respectively. Sensitivity for IFAT, IHAT, CF and DAT were 95%, 84%, 97% and 95% respectively.
International Nuclear Information System (INIS)
Nishikawa, Yoshito; Ishida, Hitoshi; Kurozumi, Yasuo
2013-01-01
Ultrasonic testing is difficult to apply to cast stainless steel which is the material of the main coolant pipes in pressurized water reactors, because of the large attenuation and scattering of ultrasonic waves caused by its macro structure. In this study, ultrasonic testing for progression of axial fatigue cracks of a welded area in the test piece of cast stainless steel pipe was performed using double big-size ultrasonic probes which were formerly developed in INSS. It was found that detection of defects that were over 6% of the target depth for the specimen thickness of 69mm is possible, and detection of defects with over 10% of the target depth is possible for all test conditions. (author)
Gong, Chester; Wu, Minghong G.; Santiago, Confesor
2016-01-01
The Unmanned Aircraft Systems Integration in the National Airspace System project, or UAS Integration in the NAS, aims to reduce technical barriers related to safety and operational challenges associated with enabling routine UAS access to the NAS. The UAS Integration in the NAS Project conducted a flight test activity, referred to as Flight Test 3 (FT3), involving several Detect-and-Avoid (DAA) research prototype systems between June 15, 2015 and August 12, 2015 at the Armstrong Flight Research Center (AFRC). This report documents the flight testing and analysis results for the NASA Ames-developed JADEM-Autoresolver DAA system, referred to as 'Autoresolver' herein. Four flight test days (June 17, 18, 22, and July 22) were dedicated to Autoresolver testing. The objectives of this test were as follows: 1. Validate CPA prediction accuracy and detect-and-avoid (DAA, formerly known as self-separation) alerting logic in realistic flight conditions. 2. Validate DAA trajectory model including maneuvers. 3. Evaluate TCAS/DAA interoperability. 4. Inform final Minimum Operating Performance Standards (MOPS). Flight test scenarios were designed to collect data to directly address the objectives 1-3. Objective 4, inform final MOPS, was a general objective applicable to the UAS in the NAS project as a whole, of which flight test is a subset. This report presents analysis results completed in support of the UAS in the NAS project FT3 data review conducted on October 20, 2015. Due to time constraints and, to a lesser extent, TCAS data collection issues, objective 3 was not evaluated in this analysis.
Wojewoda, Christina M; Sercia, Linda; Navas, Maria; Tuohy, Marion; Wilson, Deborah; Hall, Geraldine S; Procop, Gary W; Richter, Sandra S
2013-07-01
Rapid identification of pathogens from blood cultures can decrease lengths of stay and improve patient outcomes. We evaluated the accuracy of the Verigene Gram-positive blood culture (BC-GP) nucleic acid test for investigational use only (Nanosphere, Inc., Northbrook, IL) for the identification of Gram-positive bacteria from blood cultures. The detection of resistance genes (mecA in Staphylococcus aureus and Staphylococcus epidermidis and vanA or vanB in Enterococcus faecium and Enterococcus faecalis) by the BC-GP assay also was assessed. A total of 186 positive blood cultures (in BacT/Alert FA bottles) with Gram-positive cocci observed with Gram staining were analyzed using the BC-GP assay. The BC-GP results were compared with the identification and susceptibility profiles obtained with routine methods in the clinical laboratory. Discordant results were arbitrated with additional biochemical, cefoxitin disk, and repeat BC-GP testing. The initial BC-GP organism identification was concordant with routine method results for 94.6% of the blood cultures. Only 40% of the Streptococcus pneumoniae identifications were correct. The detection of the mecA gene for 69 blood cultures with only S. aureus or S. epidermidis was concordant with susceptibility testing results. For 3 of 6 cultures with multiple Staphylococcus spp., mecA detection was reported but was correlated with oxacillin resistance in a species other than S. aureus or S. epidermidis. The detection of vanA agreed with susceptibility testing results for 45 of 46 cultures with E. faecalis or E. faecium. Comparison of the mean times to results for each organism group showed that BC-GP results were available 31 to 42 h earlier than phenotypic identifications and 41 to 50 h earlier than susceptibility results.
DEFF Research Database (Denmark)
Bjerrum, Andreas; Milter, Maya Christel; Andersen, Ole
2015-01-01
BACKGROUND: Limited data exist on adenoma surveillance as recommended in the European guidelines for quality assurance in colorectal cancer (CRC) screening and diagnosis after faecal occult blood test (FOBT) screening. OBJECTIVE: To assess the European guidelines for adenoma surveillance after CRC...... of CRC was higher in risk group C than A (RR 5.20, 95% confidence interval: 0.63-42.58), but not statistically significant. In risk group C, half of new advanced adenomas were detected within the first year and four of nine CRC were detected within 3 years. CONCLUSION: Risk stratification of adenoma...
Directory of Open Access Journals (Sweden)
J. Q. Zhao
2016-06-01
Full Text Available Accurate and timely change detection of Earth’s surface features is extremely important for understanding relationships and interactions between people and natural phenomena. Many traditional methods of change detection only use a part of polarization information and the supervised threshold selection. Those methods are insufficiency and time-costing. In this paper, we present a novel unsupervised change-detection method based on quad-polarimetric SAR data and automatic threshold selection to solve the problem of change detection. First, speckle noise is removed for the two registered SAR images. Second, the similarity measure is calculated by the test statistic, and automatic threshold selection of KI is introduced to obtain the change map. The efficiency of the proposed method is demonstrated by the quad-pol SAR images acquired by Radarsat-2 over Wuhan of China.
Directory of Open Access Journals (Sweden)
Sun Tao
2010-10-01
Full Text Available Abstract Background Duck enteritis virus (DEV infection causes substantial economic losses to the worldwide duck-producing areas. The monitoring of DEV-specific antibodies is a key to evaluate the effect of DEV vaccine and develop rational immunization programs. Thus, in this study, an immunochromatographic strip (ICS test was developed for detecting DEV serum antibodies. Results The ICS test is based on membrane chromatography, and uses both the purified recombinant UL51 protein conjugated with colloidal gold and goat anti-rabbit IgG conjugated with colloidal gold as tracers, the purified recombinant UL51 protein as the capture reagent at the test line, and rabbit IgG as the capture reagent at the control line. The specificity of the ICS was evaluated by sera against DEV, Duck hepatitis virus (DHV, Riemerella anatipestifer (RA, Duck E. coli, Muscovy duck parvovirus (MPV, or Duck Influenza viruses (DIV. Only sera against DEV showed the strong positive results. In order to determine the sensitivity of the ICS, anti-DEV serum diluted serially was tested, and the minimum detection limit of 1:128 was obtained. The ICS components, which are provided in a sealed package, require no refrigeration and are stable for 12 months. To evaluate the effect of the ICS, 110 duck serum samples collected from several non-immune duck flocks were simultaneously tested by the ICS test, enzyme-linked immunosorbent assay (ELISA and neutralization test (NT. The results showed that the sensitivity of the ICS test was almost consistent with ELISA and much higher than NT, has low cost, and is rapid (15 min and easy to perform with no requirement of specialized equipment, reagent or technicians. Conclusions In this work, we successfully developed a simple and rapid ICS test for detecting DEV serum antibodies for the first time. The ICS test was high specific and sensitive for the rapid detection of anti-DEV antibodies, and has great potential to be used for the serological
International Nuclear Information System (INIS)
Williams, D.L.
1999-01-01
International Monitoring System (IMS) stations are being deployed worldwide in support of the Comprehensive [Nuclear] Test Ban Treaty (CTBT). The highly sensitive radionuclide monitoring stations regularly sample airborne radionuclide particulates to determine whether fission products are present in the atmosphere that may be indicative of a nuclear weapons test. Standards have been set for these stations regarding their operation regime and the minimum detectable concentrations (MDCs) for specific radionuclides likely to be present after a nuclear weapons test. This study uses actual CTBT monitoring data to relate a subset of the specified operational standards with the listed MDC limits. It is determined that a relationship exists between the specified operational regime and the MDC values. Since the background radioactivity is largely a function of the radon and thoron progeny, longer decay operational regimes allow for a reduction in the background. For longer lived radionuclides, this corresponds to a reduction in MDC. (author)
Koishi, Andrea Cristine; Suzukawa, Andréia Akemi; Zanluca, Camila; Camacho, Daria Elena; Comach, Guillermo; Duarte Dos Santos, Claudia Nunes
2018-03-01
Zika virus (ZIKV) is an emerging arbovirus belonging to the genus flavivirus that comprises other important public health viruses, such as dengue (DENV) and yellow fever (YFV). In general, ZIKV infection is a self-limiting disease, however cases of Guillain-Barré syndrome and congenital brain abnormalities in newborn infants have been reported. Diagnosing ZIKV infection remains a challenge, as viral RNA detection is only applicable until a few days after the onset of symptoms. After that, serological tests must be applied, and, as expected, high cross-reactivity between ZIKV and other flavivirus serology is observed. Plaque reduction neutralization test (PRNT) is indicated to confirm positive samples for being more specific, however it is laborious intensive and time consuming, representing a major bottleneck for patient diagnosis. To overcome this limitation, we developed a high-throughput image-based fluorescent neutralization test for ZIKV infection by serological detection. Using 226 human specimens, we showed that the new test presented higher throughput than traditional PRNT, maintaining the correlation between results. Furthermore, when tested with dengue virus samples, it showed 50.53% less cross reactivity than MAC-ELISA. This fluorescent neutralization test could be used for clinical diagnosis confirmation of ZIKV infection, as well as for vaccine clinical trials and seroprevalence studies.
Production and detection of cold anti-hydrogen atoms A first step towards high precision CPT test
Variola, A; Bonomi, G; Boutcha, A; Bowe, P; Carraro, C; Cesar, C L; Charlton, M; Doser, Michael; Filippini, V; Fontana, A; Fujiwara, M C; Funakoshi, R; Genova, P; Hangst, J S; Hayano, R S; Jørgensen, L V; Lagomarsino, V; Landua, Rolf; Lindelöf, D; Lodi-Rizzini, E; Macri, M; Madsen, N; Manuzio, G; Montagna, P; Pruys, H S; Regenfus, C; Rotondi, A; Riedler, P; Testera, G; Van der Werf, D P
2003-01-01
Observations of anti-hydrogen in small quantities have been reported at CERN and at FermiLab, but these experiments were not suited to spectroscopy experiments. In 2002 the ATHENA collaboration reported the production and detection of very low energy anti-hydrogen atoms produced in cryogenic environment. This is the first major step in the study of antiatom's internal structure and it can lead to a high precision test of the CPT fundamental symmetry. The method of production and detection of cold anti-hydrogen will be introduced. The absolute rate of anti-hydrogen production and the signal to background ratio in the ATHENA experiment will be discussed. (7 refs) .
International Nuclear Information System (INIS)
Majidi, A.P.; Streicher, A.
1986-01-01
Three different electrochemical reactivation tests are compared with etch structures produced in the electrolytic oxalic acid etch test. These nondestructive tests are needed to evaluate welded stainless steel pipes and other plant equipment for susceptibility to intergranular attack. Sensitization associated with precipitates of chromium carbides at grain boundaries can make these materials subject to intergranular attack in acids and, in particular, to intergranular stress corrosion cracking in high-temperature (289 0 C) water on boiling water nuclear reactor power plants. In the first of the two older reactivation tests, sensitization is detected by the electrical charge generated during reactivation. In the second, it is measured by the ratio of maximum currents generated by a prior anodic loop and the reactivation loop. A third, simpler reactivation method based on a measurement of the maximum current generated during reactivation is proposed. If the objective of the field tests, which are to be carried out with portable equipment, is to distinguish between nonsensitized and sensitized material, this can be accomplished most simply, most rapidly, and at lowest cost by an evaluation of oxalic acid etch structures
Peng, Linda X; Wallace, Morgan; Andaloro, Bridget; Fallon, Dawn; Fleck, Lois; Delduco, Dan; Tice, George
2011-01-01
The BAX System PCR assay for Salmonella detection in foods was previously validated as AOAC Research Institute (RI) Performance Tested Method (PTM) 100201. New studies were conducted on beef and produce using the same media and protocol currently approved for the BAX System PCR assay for E. coli O157:H7 multiplex (MP). Additionally, soy protein isolate was tested for matrix extension using the U.S. Food and Drug Administration-Bacteriological Analytical Manual (FDA-BAM) enrichment protocols. The studies compared the BAX System method to the U.S. Department of Agriculture culture method for detecting Salmonella in beef and the FDA-BAM culture method for detecting Salmonella in produce and soy protein isolate. Method comparison studies on low-level inoculates showed that the BAX System assay for Salmonella performed as well as or better than the reference method for detecting Salmonella in beef and produce in 8-24 h enrichment when the BAX System E. coli O157:H7 MP media was used, and soy protein isolate in 20 h enrichment with lactose broth followed by 3 h regrowth in brain heart infusion broth. An inclusivity panel of 104 Salmonella strains with diverse serotypes was tested by the BAX System using the proprietary BAX System media and returned all positive results. Ruggedness factors involved in the enrichment phase were also evaluated by testing outside the specified parameters, and none of the factors examined affected the performance of the assay.
Development of sputter ion pump based SG leak detection system for Fast Breeder Test Reactor
International Nuclear Information System (INIS)
Babu, B.; Sureshkumar, K.V.; Srinivasan, G.
2013-01-01
Highlights: ► Development and commissioning of SG leak detection system for FBTR. ► Development of Robust method of using sputter ion pump based system. ► Modifications for improving reliability and availability. ► On line injection of hydrogen in sodium during reactor operation. ► Triplication of the SG leak detection system. - Abstract: The Fast Breeder Test Reactor (FBTR) is a 40 MWt, loop type sodium cooled fast reactor built at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam as a fore-runner to the second stage of Indian nuclear power programme. The reactor design is based on the French reactor Rapsodie with several modifications which include the provision of a steam-water circuit and turbo-generator. FBTR uses sodium as the coolant in the main heat transport medium to transfer heat from the reactor core to the feed water in the tertiary loop for producing superheated steam, which drives the turbo-generator. Sodium and water flow in shell and tube side respectively, separated by thin-walls of the ferritic steel tubes of the once-through steam generator (SG). Material defects in these tubes can lead to leakage of water into sodium, resulting in sodium water reactions leading to undesirable consequences. Early detection of water or steam leaks into sodium in the steam generator units of liquid metal fast breeder reactors (LMFBR) is an important requirement from safety and economic considerations. The SG leak in FBTR is detected by Sputter Ion Pump (SIP) based Steam Generator Leak Detection (SGLD) system and Thermal Conductivity Detector (TCD) based Hydrogen in Argon Detection (HAD) system. Many modifications were carried out in the SGLD system for the reactor operation to improve the reliability and availability. This paper details the development and the acquired experience of SIP based SGLD system instrumentation for real time hydrogen detection in sodium for FBTR.
Zhang, Yuhan; Lu, Dr. Thomas
2010-01-01
The objectives of this project were to develop a ROI (Region of Interest) detector using Haar-like feature similar to the face detection in Intel's OpenCV library, implement it in Matlab code, and test the performance of the new ROI detector against the existing ROI detector that uses Optimal Trade-off Maximum Average Correlation Height filter (OTMACH). The ROI detector included 3 parts: 1, Automated Haar-like feature selection in finding a small set of the most relevant Haar-like features for detecting ROIs that contained a target. 2, Having the small set of Haar-like features from the last step, a neural network needed to be trained to recognize ROIs with targets by taking the Haar-like features as inputs. 3, using the trained neural network from the last step, a filtering method needed to be developed to process the neural network responses into a small set of regions of interests. This needed to be coded in Matlab. All the 3 parts needed to be coded in Matlab. The parameters in the detector needed to be trained by machine learning and tested with specific datasets. Since OpenCV library and Haar-like feature were not available in Matlab, the Haar-like feature calculation needed to be implemented in Matlab. The codes for Adaptive Boosting and max/min filters in Matlab could to be found from the Internet but needed to be integrated to serve the purpose of this project. The performance of the new detector was tested by comparing the accuracy and the speed of the new detector against the existing OTMACH detector. The speed was referred as the average speed to find the regions of interests in an image. The accuracy was measured by the number of false positives (false alarms) at the same detection rate between the two detectors.
Detected Surface Effects of the September 3, 2017 Declared Nuclear Test
Pabian, F. V.
2017-12-01
Satellite-based synthetic aperture radar (SAR) data of North Korea's Punggye-ri Nuclear Test Site, together with new electro-optical commercial satellite imagery and a short official video (apparently recorded during the most recent test), provide additional insights on the widespread surface disturbances[1] around the peak of Mt. Mantap that were caused by North Korea's sixth and by far largest nuclear test (over one hundred kilotons). While a number of visible landslides have already been reported by this author and others, this additional data reveals more information about the widespread nature of the detected movements that indicate a general slumping/compression of the top 200 meters of the mountain consisting of loosely consolidated volcanic ash deposits above a nonconformity with underlying basement diorite/granites. A closer look at the one previously noted zone of localized slippage/subsidence located within the volcanic deposits, revealed that several healthy trees have been knocked down. The new image data empirically confirms previous seismological estimates that the detonation occurred somewhere under Mt. Mantap. The North Korean-sourced short video, which shows a large dust cloud rising up from the mountain along with a probable active rockfall in a pre-existing landslide scar, provides additional new evidence consistent with that conclusion. However, the broad-scale nature of those movements inhibits more precise geolocation of the test within the mountain using imagery. [1] Surface displacements include landslides, spall, cracks, rock falls, small fault displacements, and earth movement including slippage/subsidence within pre-existing surface features such as small depressions as previously reported here: http://www.38north.org/2017/01/fpabiandcoblentz010617/ and http://www.38north.org/2017/09/punggye090517/ and http://www.38north.org/2017/09/punggye091217/
Validation of pre-coated ELISA tests to detect antibodies against T. congolense and T. vivax
International Nuclear Information System (INIS)
Shumba, W.
2000-01-01
The anti-trypanosomal antibody detecting enzyme linked immunosorbent assay (ELISA) was first described in 1977 and was further developed for use in large scale surveys in Zimbabwe. More recently, the IAEA initiated a programme to improve the robustness and standardisation of the assay. The IAEA supplied plates pre-coated with either a crude T. congolense or T. vivax antigen and the reagents necessary for analysing samples. Parasitologically positive and negative sera were used to validate and determine the cut-off values of the two tests. The samples were tested and results analysed using a variety of cut-off values. The tests provided similar information although the T. congolense pre-coated plates gave significantly higher optical density values than the plates coated with T. vivax. Sensitivity and specificity values were calculated using the different cut-off points. Results indicate that the test using T. congolense antigen had the highest specificity and sensitivity for a given cut-off value. Although the test could distinguish positive from negative sera, it was quite difficult to provide a suitable cut-off value, but the value should be dictated by the use of the test. (author)
Cassidy, Brianna M; Lu, Zhenyu; Martin, Jennifer P; Tazik, Shawna K; Kellogg, Katie W; DeJong, Stephanie A; Belliveau, Elle O; Kilgore, Katherine E; Ervin, Samantha M; Meece-Rayle, Mackenzie; Abraham, Alyssa M; Myrick, Michael L; Morgan, Stephen L
2017-09-01
The luminol test has been used for over 60 years by forensic investigators for presumptive identification of blood and visualization of blood splatter patterns. Multiple studies have estimated the limit of detection (LD) for bloodstains when luminol is employed, with results ranging from 100× to 5,000,000× dilute. However, these studies typically have not identified and controlled important experimental variables which may affect the luminol LD for bloodstains. Without control of experimental parameters in the laboratory, variables which affect the potential of presumptive bloodstain test methods remain largely unknown, and comparisons required to establish new, more powerful detection methods are simply impossible. We have developed a quantitative method to determine the relationship between the amount of blood present and its reaction with luminol by measuring, under controlled conditions, the resulting chemiluminescent intensity with a video camera, combined with processing of the digital intensity data. The method resulted in an estimated LD for bloodstains on cotton fabric at ∼200,000× diluted blood with a specific luminol formulation. Although luminol is the focus of this study, the experimental protocol used could be modified to study effects of variables using other blood detection reagents. Copyright © 2017 Elsevier B.V. All rights reserved.
Zero-inflated Poisson model based likelihood ratio test for drug safety signal detection.
Huang, Lan; Zheng, Dan; Zalkikar, Jyoti; Tiwari, Ram
2017-02-01
In recent decades, numerous methods have been developed for data mining of large drug safety databases, such as Food and Drug Administration's (FDA's) Adverse Event Reporting System, where data matrices are formed by drugs such as columns and adverse events as rows. Often, a large number of cells in these data matrices have zero cell counts and some of them are "true zeros" indicating that the drug-adverse event pairs cannot occur, and these zero counts are distinguished from the other zero counts that are modeled zero counts and simply indicate that the drug-adverse event pairs have not occurred yet or have not been reported yet. In this paper, a zero-inflated Poisson model based likelihood ratio test method is proposed to identify drug-adverse event pairs that have disproportionately high reporting rates, which are also called signals. The maximum likelihood estimates of the model parameters of zero-inflated Poisson model based likelihood ratio test are obtained using the expectation and maximization algorithm. The zero-inflated Poisson model based likelihood ratio test is also modified to handle the stratified analyses for binary and categorical covariates (e.g. gender and age) in the data. The proposed zero-inflated Poisson model based likelihood ratio test method is shown to asymptotically control the type I error and false discovery rate, and its finite sample performance for signal detection is evaluated through a simulation study. The simulation results show that the zero-inflated Poisson model based likelihood ratio test method performs similar to Poisson model based likelihood ratio test method when the estimated percentage of true zeros in the database is small. Both the zero-inflated Poisson model based likelihood ratio test and likelihood ratio test methods are applied to six selected drugs, from the 2006 to 2011 Adverse Event Reporting System database, with varying percentages of observed zero-count cells.
Oestrus Detection in Dairy Cows Using Likelihood Ratio Tests
DEFF Research Database (Denmark)
Jónsson, Ragnar Ingi; Björgvinssin, Trausti; Blanke, Mogens
2008-01-01
This paper addresses detection of oestrus in dairy cows using methods from statistical change detection. The activity of the cows was measured by a necklace attached sensor. Statistical properties of the activity measure were investigated. Using data sets from 17 cows, diurnal activity variations...
Singh, Monika; Bhoge, Rajesh K; Randhawa, Gurinderjit
2018-04-20
Background : Confirming the integrity of seed samples in powdered form is important priorto conducting a genetically modified organism (GMO) test. Rapid onsite methods may provide a technological solution to check for genetically modified (GM) events at ports of entry. In India, Bt cotton is the commercialized GM crop with four approved GM events; however, 59 GM events have been approved globally. GMO screening is required to test for authorized GM events. The identity and amplifiability of test samples could be ensured first by employing endogenous genes as an internal control. Objective : A rapid onsite detection method was developed for an endogenous reference gene, stearoyl acyl carrier protein desaturase ( Sad1 ) of cotton, employing visual and real-time loop-mediated isothermal amplification (LAMP). Methods : The assays were performed at a constant temperature of 63°C for 30 min for visual LAMP and 62ºC for 40 min for real-time LAMP. Positive amplification was visualized as a change in color from orange to green on addition of SYBR ® Green or detected as real-time amplification curves. Results : Specificity of LAMP assays was confirmed using a set of 10 samples. LOD for visual LAMP was up to 0.1%, detecting 40 target copies, and for real-time LAMP up to 0.05%, detecting 20 target copies. Conclusions : The developed methods could be utilized to confirm the integrity of seed powder prior to conducting a GMO test for specific GM events of cotton. Highlights : LAMP assays for the endogenous Sad1 gene of cotton have been developed to be used as an internal control for onsite GMO testing in cotton.
Directory of Open Access Journals (Sweden)
Romeo T. Cristina
2012-12-01
Full Text Available Zebrafish are vertebrate animals often used in research for wastewaters, environment chemicals, cancer and diabetes drugs due to their speed and ease for handling and obtaining test results. Organisms capacity to detect and avoid contaminated soils reveals soils stressor potential and has an ecological relevance indepted with its direct relationship to soil biodiversity and it’s quality as a habitat for the organism. Soil pollution tests were accomplished on arthropods (Collembola, earthworms, oligochaete worms (Enchytraeidae, this being behavior modification tests, observing which species avoids contaminated soils and if response intensity depends on contamination degree. Using Daphnia sp. for testing it’s possible because of their sensibility to an amount of aquatic pollutants and also for their small sizes involving a use of small volumes of test substance and water for dilution.
Cambau, Emmanuelle; Allerheiligen, Vera; Coulon, Céline; Corbel, Céline; Lascols, Christine; Deforges, Lionel; Soussy, Claude-James; Delchier, Jean-Charles; Megraud, Francis
2009-01-01
The eradication rate of Helicobacter pylori by standard therapy is decreasing due to antibiotic resistance, mainly to clarithromycin. Our aim was to provide a new molecular test to guide the treatment of new and relapsed cases. We first studied 126 H. pylori strains for phenotypic (MIC) and genotypic resistance to clarithromycin (rrl mutation) and levofloxacin (gyrA mutation) and then developed a DNA strip genotyping test on the basis of the correlation results and literature data. Clinical strains (n = 92) and gastric biopsy specimens containing H. pylori (n = 105) were tested blindly with the new molecular test GenoType HelicoDR. The presence of mutations or the absence of hybridization with wild-type sequences was predictive, in rrl for clarithromycin resistance in 91 cases (mostly the A2147G mutation) and in gyrA for levofloxacin resistance in 58 cases (mutations at codon 87 or 91). Genotyping revealed a mix of genotypes in 33% of the cases, reflecting a coinfection or selection for resistant mutants. The sensitivity and specificity of detecting resistance were 94% and 99% for clarithromycin and 87% and 98.5% for levofloxacin, respectively. The concordance scores were 0.96 for clarithromycin and 0.94 for levofloxacin. With global resistance rates of 46% for clarithromycin and 25% for levofloxacin, which were observed for consecutive positive biopsy specimens from 2007 and 2008, the positive and negative predictive values for detecting resistance were 99% and 94% for clarithromycin and 96% and 96% for fluoroquinolone. GenoType HelicoDR is efficient at detecting mutations predictive of antibiotic resistance in H. pylori when applied to strains or directly to gastric biopsy specimens. PMID:19759218
Matzopoulos, Richard; Lasarow, Avi; Bowman, Brett
2013-10-01
This pilot study aimed to test four substance use screening devices developed in Germany under local South African conditions and assess their utility for detecting driving under the influence of drugs (DUID) as part of the standard roadblock operations of local law enforcement agencies. The devices were used to screen a sample of motorists in the Gauteng and Western Cape provinces. The motorists were diverted for screening at roadblocks at the discretion of the law enforcement agencies involved, as per their standard operating procedures. Fieldworkers also administered a questionnaire that described the screening procedure, as well as information about vehicles, demographic information about the motorists and their attitudes to the screening process during testing. Motorists tested positive for breath alcohol in 28% of the 261 cases tested. Oral fluid was screened for drugs as per the standard calibrated cut-offs of all four devices. There were 14 cases where the under-influence drivers tested positive for alcohol and drugs simultaneously, but 14% of the 269 drivers drug-screened tested positive for drugs only. After alcohol, amphetamine, methamphetamine and cocaine were the most common drugs of impairment detected. The results suggest that under normal enforcement procedures only 76% of drivers impaired by alcohol and other drugs would have been detected. In more than 70% of cases the tests were administered within 5 min and this is likely to improve with more regular use. It was clear that the pilot screening process meets global testing standards. Although use of the screening devices alone would not serve as a basis for prosecution and provisions would need to be made for the confirmation of results through laboratory testing, rollout of this screening process would improve operational efficiency in at least two ways. Firstly, the accuracy of the tests will substantially decrease confirmatory test loads. Secondly, laboratory drug testing can be restricted to
Leak detection : Principles and practice
International Nuclear Information System (INIS)
Rama Rao, V.V.K.
1981-01-01
Principles of leak detection are explained and various aspects of leak detection techniques and leak detectors are reviewed. The review covers: units for leaks and leak tightness, classification of leaks, timing of leak testing, designing for ease of leak testing of any job, methods of leak detection, their ranges of application and limitations, leak detectors, response time of leak test, minimum detectable concentration of search gas during leak tests, and validity of leak tests. Helium mass spectrometer type leak detector and technique are described in detail. Recent improvements in leak detectors and techniques, particularly mass spectrometer leak detectors using gases other than helium (e.g. hydrogen, argon) are also covered in the review. (M.G.B.)
Directory of Open Access Journals (Sweden)
Nestani Tukvadze
Full Text Available The WHO has recommended the implementation of rapid diagnostic tests to detect and help combat M/XDR tuberculosis (TB. There are limited data on the performance and impact of these tests in field settings.The performance of the commercially available Genotype MTBDRplus molecular assay was compared to conventional methods including AFB smear, culture and drug susceptibility testing (DST using both an absolute concentration method on Löwenstein-Jensen media and broth-based method using the MGIT 960 system. Sputum specimens were obtained from TB suspects in the country of Georgia who received care through the National TB Program.Among 500 AFB smear-positive sputum specimens, 458 (91.6% had both a positive sputum culture for Mycobacterium tuberculosis and a valid MTBDRplus assay result. The MTBDRplus assay detected isoniazid (INH resistance directly from the sputum specimen in 159 (89.8% of 177 specimens and MDR-TB in 109 (95.6% of 114 specimens compared to conventional methods. There was high agreement between the MTBDRplus assay and conventional DST results in detecting MDR-TB (kappa = 0.95, p<0.01. The most prevalent INH resistance mutation was S315T (78% in the katG codon and the most common rifampicin resistance mutation was S531L (68% in the rpoB codon. Among 13 specimens from TB suspects with negative sputum cultures, 7 had a positive MTBDRplus assay (3 with MDR-TB. The time to detection of MDR-TB was significantly less using the MTBDRplus assay (4.2 days compared to the use of standard phenotypic tests (67.3 days with solid media and 21.6 days with broth-based media.Compared to conventional methods, the MTBDRplus assay had high accuracy and significantly reduced time to detection of MDR-TB in an area with high MDR-TB prevalence. The use of rapid molecular diagnostic tests for TB and drug resistance should increase the proportion of patients promptly placed on appropriate therapy.
Wang, Jing; Feng, Shangyuan; Lin, Juqiang; Zeng, Yongyi; Li, Ling; Huang, Zufang; Li, Buhong; Zeng, Haishan; Chen, Rong
2013-11-01
Surface-enhanced Raman spectroscopy (SERS) of serum albumin and globulin were employed to detect hepatocellular carcinoma (HCC). Tentative assignments of SERS bands show specific biomolecular changes associated with cancer development. These changes include a decrease in relative amounts of tryptophan, glutamine, glycine, and serine, indicating excessive consumption of amino acids for protein duplication. Principal component analysis was also introduced to analyze the obtained spectra, resulting in both diagnostic sensitivity and specificity of 100%. More importantly, it reveals that this method can detect HCC patients with alpha-fetoprotein negative test results, suggesting its great potential as a new alternative to detect HCC.
Moen, Johannes K.
1936-01-01
1. A skin test with a crude bacterial extract prepared from group C (Lancefield) hemolytic streptococci was used as a means of detecting possible carriers of the streptococcus causing epizootic lymphadenitis in guinea pigs. A positive test similar to a positive tuberculin reaction was considered presumptive evidence of present or recent infection with this streptococcus. 2. 20 positive reactors were found in 330 supposedly normal guinea pigs. 3. 195 negatively reacting animals were used as a breeding stock which yielded 1,296 progeny over a period of 15 months. None of the breeding stock or their progeny showed evidence of spontaneous lymphadenitis. Skin tests of 100 of the progeny were all negative. 4. The use of this skin test as a means of obtaining guinea pig breeding stock free of the streptococcus causing spontaneous lymphadenitis is suggested. PMID:19870552
Asakawa, A; Fueki, K; Ohyama, T
2005-09-01
The aim of this study was to determine the sensitivity of the Mixing Ability Test to detect improvement of masticatory function in subjects on transition from old to new removable partial dentures. Thirty-two subjects (seven males, 25 females, mean age 65.0 years) with distal extension partially edentulous area in mandible and/or maxilla participated in the study. The following reasons were presented for replacing the old removable partial dentures with new ones: fracture and/or poor fitness of retainers, extraction of abutment teeth, poor fitness of denture base, severe wear of artificial teeth and request for metal base dentures. Masticatory function with old and new removable partial dentures after an adaptation period (mean 27.4 weeks) was evaluated by the Mixing Ability Test. Subjects were asked to masticate five two-coloured wax cubes with each removable partial denture. Mixing Ability Index was obtained from the colour mixture and shape of the masticated cubes. Wilcoxon signed-rank test was used to test the difference of Mixing Ability Indexes between old and new removable partial dentures. The mixing ability indexes with new removable partial dentures (mean+/- s.d.: 0.70+/- 0.68) was significantly higher (Premovable partial dentures (-0.11+/-1.13). The results suggest that the Mixing Ability Test was capable of detecting improvement in masticatory function with new removable partial dentures.
Živanović, Dragan; Simić, Milan; Kokolanski, Zivko; Denić, Dragan; Dimcev, Vladimir
2018-04-01
Software supported procedure for generation of long-time complex test sentences, suitable for testing the instruments for detection of standard voltage quality (VQ) disturbances is presented in this paper. This solution for test signal generation includes significant improvements of computer-based signal generator presented and described in the previously published paper [1]. The generator is based on virtual instrumentation software for defining the basic signal parameters, data acquisition card NI 6343, and power amplifier for amplification of output voltage level to the nominal RMS voltage value of 230 V. Definition of basic signal parameters in LabVIEW application software is supported using Script files, which allows simple repetition of specific test signals and combination of more different test sequences in the complex composite test waveform. The basic advantage of this generator compared to the similar solutions for signal generation is the possibility for long-time test sequence generation according to predefined complex test scenarios, including various combinations of VQ disturbances defined in accordance with the European standard EN50160. Experimental verification of the presented signal generator capability is performed by testing the commercial power quality analyzer Fluke 435 Series II. In this paper are shown some characteristic complex test signals with various disturbances and logged data obtained from the tested power quality analyzer.
Takechi, Hajime; Dodge, Hiroko H
2010-01-01
Aim It is highly desirable to develop a neuropsychological screening test which is sensitive to the early stage of Alzheimer’s disease (AD), and is easy to administer at the primary care physician’s (PCP’s) office. Methods Participants were 128 AD patients and 54 healthy volunteers. Brief cognitive screening tests were administered to the participants including the Mini-Mental State Examination (MMSE), Clock Drawing Test (CDT), Verbal Fluency Test (VFT), a Verbal Category Cued Memory test (CCMT) and the Scenery Picture Memory Test (SPMT). In the SPMT, a scenery picture of a living room containing 23 familiar objects was used. The administration of the SPMT comprised the first shallow memory session (Pict 1) and the second deep memory session (Pict 2). The area under the receiver–operator curve (AUC) was used to compare the efficacy of SPMT with other cognitive tests. Results Pict 1, which requires less than 2 min to complete, had the same AUC as Pict 2, and showed significantly larger AUC than MMSE, CDT and VFT for all (MMSE 19–23) and very mild (MMSE ≥ 24) AD patients. When we conducted the similar analysis separately for those younger than 75 years and those aged 75 years or older, we obtained the same results as above among the older age group. Pict 1 showed larger AUC than CCMT in overall sample and also in the older age group, although the difference was not statistically significant. Conclusion The SPMT could be useful for detection of mild and very mild AD in settings even where time is limited. PMID:20446933
Dyck, P J; Zimmerman, I; Gillen, D A; Johnson, D; Karnes, J L; O'Brien, P C
1993-08-01
We recently found that vibratory detection threshold is greatly influenced by the algorithm of testing. Here, we study the influence of stimulus characteristics and algorithm of testing and estimating threshold on cool (CDT), warm (WDT), and heat-pain (HPDT) detection thresholds. We show that continuously decreasing (for CDT) or increasing (for WDT) thermode temperature to the point at which cooling or warming is perceived and signaled by depressing a response key ("appearance" threshold) overestimates threshold with rapid rates of thermal change. The mean of the appearance and disappearance thresholds also does not perform well for insensitive sites and patients. Pyramidal (or flat-topped pyramidal) stimuli ranging in magnitude, in 25 steps, from near skin temperature to 9 degrees C for 10 seconds (for CDT), from near skin temperature to 45 degrees C for 10 seconds (for WDT), and from near skin temperature to 49 degrees C for 10 seconds (for HPDT) provide ideal stimuli for use in several algorithms of testing and estimating threshold. Near threshold, only the initial direction of thermal change from skin temperature is perceived, and not its return to baseline. Use of steps of stimulus intensity allows the subject or patient to take the needed time to decide whether the stimulus was felt or not (in 4, 2, and 1 stepping algorithms), or whether it occurred in stimulus interval 1 or 2 (in two-alternative forced-choice testing). Thermal thresholds were generally significantly lower with a large (10 cm2) than with a small (2.7 cm2) thermode.(ABSTRACT TRUNCATED AT 250 WORDS)
Estimated accuracy of classification of defects detected in welded joints by radiographic tests
International Nuclear Information System (INIS)
Siqueira, M.H.S.; De Silva, R.R.; De Souza, M.P.V.; Rebello, J.M.A.; Caloba, L.P.; Mery, D.
2004-01-01
This work is a study to estimate the accuracy of classification of the main classes of weld defects detected by radiography test, such as: undercut, lack of penetration, porosity, slag inclusion, crack or lack of fusion. To carry out this work non-linear pattern classifiers were developed, using neural networks, and the largest number of radiographic patterns as possible was used as well as statistical inference techniques of random selection of samples with and without repositioning (bootstrap) in order to estimate the accuracy of the classification. The results pointed to an estimated accuracy of around 80% for the classes of defects analyzed. (author)
Estimated accuracy of classification of defects detected in welded joints by radiographic tests
Energy Technology Data Exchange (ETDEWEB)
Siqueira, M.H.S.; De Silva, R.R.; De Souza, M.P.V.; Rebello, J.M.A. [Federal Univ. of Rio de Janeiro, Dept., of Metallurgical and Materials Engineering, Rio de Janeiro (Brazil); Caloba, L.P. [Federal Univ. of Rio de Janeiro, Dept., of Electrical Engineering, Rio de Janeiro (Brazil); Mery, D. [Pontificia Unversidad Catolica de Chile, Escuela de Ingenieria - DCC, Dept. de Ciencia de la Computacion, Casilla, Santiago (Chile)
2004-07-01
This work is a study to estimate the accuracy of classification of the main classes of weld defects detected by radiography test, such as: undercut, lack of penetration, porosity, slag inclusion, crack or lack of fusion. To carry out this work non-linear pattern classifiers were developed, using neural networks, and the largest number of radiographic patterns as possible was used as well as statistical inference techniques of random selection of samples with and without repositioning (bootstrap) in order to estimate the accuracy of the classification. The results pointed to an estimated accuracy of around 80% for the classes of defects analyzed. (author)
Ni, Zhengyuan; Yan, Huimin; Ni, Xuxiang; Zhang, Xiuda
2017-10-01
The research of the multifunctional analyzer which integrates absorbance detection, fluorescence detection, time-resolved fluorescence detection, biochemical luminescence detection methods, can make efficient detection and analysis for a variety of human body nutrients. This article focuses on the absorbance detection and fluorescence detection system. The two systems are modular in design and controlled by embedded system, to achieve automatic measurement according to user settings. In the optical path design, the application of confocal design can improve the optical signal acquisition capability, and reduce the interference. A photon counter is used for detection, and a high performance counter module is designed to measure the output of photon counter. In the experiment, we use neutral density filters and potassium dichromate solution to test the absorbance detection system, and use fluorescein isothiocyanate FITC for fluorescence detection system performance test. The experimental results show that the absorbance detection system has a detection range of 0 4OD, and has good linearity in the detection range, while the fluorescence detection system has a high sensitivity of 1pmol/L concentration.
Tests to Detect Colorectal Cancer and Polyps
... follow-up care needed after the test The convenience of the test The cost of the test ... by digital rectal examination: A comparison with recommended sampling practice. Annals of Internal Medicine 2005; 142(2): ...
International Nuclear Information System (INIS)
Mainet Gonzalez, Damian; Palenzuela Gardon, Daniel O; Diaz Argudin, Tamara
2007-01-01
The disappearance of antigen e of hepatitis B in the presence of the plasmatic antibodies against antigen e may indicate a satisfactory therapeutic response in patients with chronic hepatitis B. The immuno-chromatographic test carried out in the diagnosis of diseases use different antibody combinations and may employ the avidin or streptavidin-biotin technology to develop a rapid immuno-chromatographic test for the detection of antibodies anti-antigen e in the plasma. They were detected in the laboratory by means of two fast immuno-chromatographic tests when using in one of them the avidin-biotin technology. These tests are carried out with a one-step competitive inhibition format and amplified or not with avidin-biotin. Monoclonal antibodies against antigen e obtained by cellular hybridization were used. Forty-six plasmatic samples classified as positive and negative to the anti-antigen antibodies were evaluated with a reference immunochromatographic test Advanced QualityTM. The possible expiry time of the biological reagents forming part of these tests were studied with accelerated thermal-stability experiments. The possible interference in the plasma of some of the biochemical compounds used in these trials was analyzed. Four murine monoclonal antibodies anti-antigen e were obtained and only one of them was used in these immunochromatographic tests with an anti-antigen polyclonal antibody conjugated with gold. Both tests and their stable biological reagents discriminated the positive and negative samples to the antibodies anti-antigen e, as well as the commercial test. There was no interference in the biochemical compounds studied in these tests. Both immuno-chromatographic tests made in the laboratory are useful to detect antibodies anti-antigen e in the plasma. The avidin-biotin increased the analytical sensitivity of this type of fast immuno-chromatographic test without altering its performance features. (Author)
Cipriano, R.C.; Ford, L.A.; Smith, D.R.; Schachte, J.H.; Petrie, C.J.
1997-01-01
Accurate detection of Aeromonas salmonicida subsp. salmonicida (the cause of furunculosis disease) in covertly infected salmonids is difficult and is a cause of concern for those involved in fish health inspection and resource management programs. In this study, we examined populations of brook trout Salvelinus fontinalis, Atlantic salmon Salmo salar, and lake trout Salvelinus namaycush that previously sustained natural episodes of furunculosis. Consequently, the sampled fish were presumed to harbor latent infections. Mucus, gill, liver, kidney, heart, spleen, and intestine samples (N = 100 fish per group sampled) were processed and examined by (1) direct dilution counts and (2) quadrant streaking after a 48-h pre-enrichment in trypticase soy broth (TSB). Another subsample of fish from each group was then subjected to stress-inducible furunculosis tests. Stress tests detected A. salmonicida in three of four groups of fish that were examined whereas the pathogen was detected in only two of the groups analyzed with culture-based assays. Although pre-enrichment in TSB enhanced detection within internal sampling sites including the liver, heart, spleen, and kidney, enrichment did not enhance detection from mucus, gill, or intestinal samples.
2013-07-01
DTRA-TR-13-48 Low Power, Room Temperature Systems for the Detection and Identification of Radionuclides from Atmospheric Nuclear Test Approved for...01-C-0071 Radionuclides from Atmospheric Nuclear Tests 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Muren Chu...I IIlIl4eI ilf "tt""f;lk~ l).t::l’e.do)- mllin:: in an n-t~’Jf mlllril.: II!’ ,-kll ~".r’I::!, ..... ·hkh j,-, .:auI,,·d br thP . la-ek f.r ·;IIff
DEFF Research Database (Denmark)
Lund, Mikkel N.; Chaplin, William J.; Kjeldsen, Hans
2012-01-01
hence a candidate detection). We apply the method to solar photometry data, whose quality was systematically degraded to test the performance of the MWPS at low signal-to-noise ratios. We also compare the performance of the MWPS against the frequently applied power-spectrum-of-power-spectrum (PSx...
Genchi, Marco; Mangia, Carlo; Ferrari, Nicola; Loukeri, Sofia
2018-01-01
The performance of a rapid immunochromatographic test for the detection of Dirofilaria immitis antigens (Speed Diro™; BVT-Virbac, France) was assessed in 49 experimentally infected dogs and in 244 naturally infected animals; 142 dogs and 102 cats. In experimentally infected dogs, Speed Diro™ showed a sensitivity of 90.9% in dogs infected with one adult female worm and 100% in dogs infected with more than one female worm. Specificity was 100%. For naturally infected dogs, the Knott test and PetChek ® HTWM PF served as reference methods for microfilaremia and antigenemia, respectively. All microfilaemic dogs (55/142) were positive with Speed Diro™. Importantly, none of the 21 dogs infected with D. repens were positive. The results of Speed Diro™ for the detection of antigenemia were compared with two in-house tests, SNAP ® HTWM and Witness ® Dirofilaria, and all three tests were 100% specific and sensitive in comparison to PetChek ® HTWM PF. For the evaluation of feline samples, 102 cats were examined by echocardiography. Sera from 87 heartworm-infected cats were tested by Speed Diro™ and SNAP ® HTWM. The results of Speed Diro™ were equivalent to SNAP ® HTWM, with a sensitivity of 98.9% and a specificity of 100%.
Lack of detection of human papillomavirus infection by hybridization test in prostatic biopsies
International Nuclear Information System (INIS)
Gazzaz, Faten S; Mosli, Hisham A
2009-01-01
To explore the possibility of finding human papillomavirus (HPV) infection in the prostate tissue of a cohort of Saudi men presenting with benign prostatic hyperplasia (BPH) or prostate cancer. A cohort study on prospectively collected tissue samples was conducted at King Abdulaziz University Hospital (KAUH), Jeddah, Kingdom of Saudi Arabia from March 2007 to December 2008 on a total of 56 male patients, age range 50-93 years (average 68), diagnosed as having BPH or prostate cancer. The HPV DNA hybridization by hybrid capture 2 technology was performed on prostate biopsies of these patients to detect 18 types of HPV infection, and differentiate between 2 HPV DNA groups, the low-risk types, and the high/intermediate risk types.The tissues of all the prostatic biopsies were negative for HPV DNA. Our results, using the hybridization test, indicate that it is unlikely that HPV-16 or HPV-18, or the other tested subtypes, enhance the risk of prostate cancer. (author)
Directory of Open Access Journals (Sweden)
Chen Hai-Tang
2011-05-01
Full Text Available Abstract Background Canine leishmaniasis (CanL is endemic in western China, resulting in important public health problem. It is essential to evaluate the prevalence of canine Leishmania infantum infection for designing control policy. In the present study we report for the first time prevalence of Leishmania infection in dogs living in Jiuzhaigou County (Sichuan Provence, China, which is not only an important endemic area of CanL but also a tourism scenic spot, detected by PCR, ELISA and dipstick test. The results could provide key information for designing control programs against canine and human leishmaniasis. In addition, the complete sequence of the Leishmania isolate from Sichuan Province has not been reported to date and we present the sequences of 116 base-pair (bp fragment of the conserved region in the minicircle kinetoplast DNA (kDNA and the results of phylogenetic analyses based on the sequence of the amplified fragment. Results The proportion of dogs infected with Leishmania in Jiuzhaigou County was 36.79%, 9.43%, and 51.88% detected by ELISA, dipstick test, and PCR, respectively. The ELISA and PCR tests were more sensitive than dipstick test. The PCR method is the most sensitive way to detect dogs infected with Leishmania parasites. The total positive rate for infected dogs in the area was 59.43% by the three methods. The PCR products of 116-bp fragment amplified from the kDNA conserved region of dog blood samples and laboratory maintained L. infantum were DNA sequenced and the variation of the sequences was observed. The phylogenetic tree based on the sequences of 116-bp fragment reveals that L. infantum is more genetically related to visceralizing species L. donovani than to the Leishmania species associated with cutaneous disease. Conclusions More than half of dogs living in the endemic Jiuzhaigou County were infected by L. infantum. Control measures, such as treatment or eradication of infected dogs, or prohibition of
Turgeon, David K; Novicki, Thomas J; Quick, John; Carlson, LaDonna; Miller, Pat; Ulness, Bruce; Cent, Anne; Ashley, Rhoda; Larson, Ann; Coyle, Marie; Limaye, Ajit P; Cookson, Brad T; Fritsche, Thomas R
2003-02-01
Clostridium difficile is one of the most frequent causes of nosocomial gastrointestinal disease. Risk factors include prior antibiotic therapy, bowel surgery, and the immunocompromised state. Direct fecal analysis for C. difficile toxin B by tissue culture cytotoxin B assay (CBA), while only 60 to 85% sensitive overall, is a common laboratory method. We have used 1,003 consecutive, nonduplicate fecal samples to compare six commercially available immunoassays (IA) for C. difficile detection with CBA: Prima System Clostridium difficile Tox A and VIDAS Clostridium difficile Tox A II, which detect C. difficile toxin A; Premier Cytoclone A/B and Techlab Clostridium difficile Tox A/B, which detect toxins A and B; and ImmunoCard Clostridium difficile and Triage Micro C. difficile panels, which detect toxin A and a species-specific antigen. For all tests, Triage antigen was most sensitive (89.1%; negative predictive value [NPV] = 98.7%) while ImmunoCard was most specific (99.7%; positive predictive value [PPV] = 95.0%). For toxin tests only, Prima System had the highest sensitivity (82.2%; NPV = 98.0%) while ImmunoCard had the highest specificity (99.7%; PPV = 95.0%). Hematopoietic stem cell transplant (HSCT) patients contributed 44.7% of all samples tested, and no significant differences in sensitivity or specificity were noted between HSCT and non-HSCT patients. IAs, while not as sensitive as direct fecal CBA, produce reasonable predictive values, especially when both antigen and toxin are detected. They also offer significant advantages over CBA in terms of turnaround time and ease of use.
Directory of Open Access Journals (Sweden)
Wang ZZ
2014-04-01
Full Text Available Zhizeng Wang,1 Dejuan Zhi,2 Yang Zhao,1 Hailong Zhang,2 Xin Wang,2 Yi Ru,1 Hongyu Li1,2 1MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, People's Republic of China; 2Institute of Microbiology and Biochemical Pharmacy, School of Pharmaceutics, Lanzhou University, Lanzhou, People's Republic of China Abstract: Although high melamine (MEL intake has been proven to cause serious health problems, MEL is sometimes illegally added to milk products and animal feed, arousing serious food safety concerns. A satisfactory method of detecting MEL in onsite or in-home testing is in urgent need of development. This work aimed to explore a rapid, convenient, and cost-effective method of identifying MEL in milk products or other food by colloidal selenium-based lateral flow immunoassay. Colloidal selenium was synthesized by L-ascorbic acid to reduce seleninic acid at room temperature. After conjugation with a monoclonal antibody anti-MEL, a test strip was successfully prepared. The detection limit of the test strip reached 150 µg/kg, 1,000 µg/kg, and 800 µg/kg in liquid milk, milk powder, and animal feed, respectively. No cross-reactions with homologues cyanuric acid, cyanurodiamide, or ammelide were found. Moreover, the MEL test strip can remain stable after storage for 1 year at room temperature. Our results demonstrate that the colloidal selenium MEL test strip can detect MEL in adulterated milk products or animal feed conveniently, rapidly, and sensitively. In contrast with a colloidal gold MEL test strip, the colloidal selenium MEL test strip was easy to prepare and more cost-efficient. Keywords: melamine, selenium nanoparticles, test strip, milk, animal feed, dairy food
Barta, András; Horváth, Gábor; Horváth, Ákos; Egri, Ádám; Blahó, Miklós; Barta, Pál; Bumke, Karl; Macke, Andreas
2015-02-10
Cloud cover estimation is an important part of routine meteorological observations. Cloudiness measurements are used in climate model evaluation, nowcasting solar radiation, parameterizing the fluctuations of sea surface insolation, and building energy transfer models of the atmosphere. Currently, the most widespread ground-based method to measure cloudiness is based on analyzing the unpolarized intensity and color distribution of the sky obtained by digital cameras. As a new approach, we propose that cloud detection can be aided by the additional use of skylight polarization measured by 180° field-of-view imaging polarimetry. In the fall of 2010, we tested such a novel polarimetric cloud detector aboard the research vessel Polarstern during expedition ANT-XXVII/1. One of our goals was to test the durability of the measurement hardware under the extreme conditions of a trans-Atlantic cruise. Here, we describe the instrument and compare the results of several different cloud detection algorithms, some conventional and some newly developed. We also discuss the weaknesses of our design and its possible improvements. The comparison with cloud detection algorithms developed for traditional nonpolarimetric full-sky imagers allowed us to evaluate the added value of polarimetric quantities. We found that (1) neural-network-based algorithms perform the best among the investigated schemes and (2) global information (the mean and variance of intensity), nonoptical information (e.g., sun-view geometry), and polarimetric information (e.g., the degree of polarization) improve the accuracy of cloud detection, albeit slightly.
Mehta, Maitry S.; Paule, Suzanne M.; Hacek, Donna M.; Thomson, Richard B.; Kaul, Karen L.; Peterson, Lance R.
2008-01-01
Nasal and perianal swab specimens were tested for detection of Staphylococcus aureus and vancomycin-resistant Enterococcus species (VRE) using a laboratory-developed real-time PCR test and microbiological cultures. The real-time PCR and culture results for S. aureus were similar. PCR had adequate sensitivity, but culture was more specific for the detection of VRE.
Chow, Eric P F; Callander, Denton; Fairley, Christopher K; Zhang, Lei; Donovan, Basil; Guy, Rebecca; Lewis, David A; Hellard, Margaret; Read, Phillip; Ward, Alison; Chen, Marcus Y
2017-08-01
Syphilis rates have increased markedly among men who have sex with men (MSM) internationally. We examined trends in syphilis testing and detection of early syphilis among MSM in Australia. Serial cross-sectional analyses on syphilis testing and diagnoses among MSM attending a national sentinel network of 46 clinics in Australia between 2007 and 2014. 359313 clinic visits were included. The proportion of MSM serologically tested for syphilis annually increased in HIV-negative (48% to 91%; Ptrend syphilis cases were detected in HIV-negative and HIV-positive MSM, respectively. Among HIV-negative MSM, the proportion of infections that were early latent increased from 27% to 44% (Ptrend syphilis correlated with increasing testing coverage (r = -0.87; P = .005) or frequency (r = -0.93; P = .001). Increases in syphilis screening were associated with increased detection of asymptomatic infectious syphilis and relative falls in secondary syphilis for both HIV-positive and HIV-negative MSM nationally, suggesting interruption of syphilis progression. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.
International Nuclear Information System (INIS)
Porter, J.F.
1996-01-01
Nondestructive testing (NDT) is the use of physical and chemical methods for evaluating material integrity without impairing its intended usefulness or continuing service. Nondestructive tests are used by manufaturer's for the following reasons: 1) to ensure product reliability; 2) to prevent accidents and save human lives; 3) to aid in better product design; 4) to control manufacturing processes; and 5) to maintain a uniform quality level. Nondestructive testing is used extensively on power plants, oil and chemical refineries, offshore oil rigs and pipeline (NDT can even be conducted underwater), welds on tanks, boilers, pressure vessels and heat exchengers. NDT is now being used for testing concrete and composite materials. Because of the criticality of its application, NDT should be performed and the results evaluated by qualified personnel. There are five basic nondestructive examination methods: 1) liquid penetrant testing - method used for detecting surface flaws in materials. This method can be used for metallic and nonmetallic materials, portable and relatively inexpensive. 2) magnetic particle testing - method used to detect surface and subsurface flaws in ferromagnetic materials; 3) radiographic testing - method used to detect internal flaws and significant variation in material composition and thickness; 4) ultrasonic testing - method used to detect internal and external flaws in materials. This method uses ultrasonics to measure thickness of a material or to examine the internal structure for discontinuities. 5) eddy current testing - method used to detect surface and subsurface flaws in conductive materials. Not one nondestructive examination method can find all discontinuities in all of the materials capable of being tested. The most important consideration is for the specifier of the test to be familiar with the test method and its applicability to the type and geometry of the material and the flaws to be detected
International Nuclear Information System (INIS)
Voronov, G. S.; Berezhetskii, M. S.; Bondar’, Yu. F.; Vafin, I. Yu.; Vasil’kov, D. G.; Voronova, E. V.; Grebenshchikov, S. E.; Grishina, I. A.; Larionova, N. F.; Letunov, A. A.; Logvinenko, V. P.; Meshcheryakov, A. I.; Pleshkov, E. I.; Khol’nov, Yu. V.; Fedyanin, O. I.; Tsygankov, V. A.; Shchepetov, S. V.; Kurnaev, V. A.; Vizgalov, I. V.; Urusov, V. A.
2013-01-01
Results are presented from L-2M stellarator experiments on testing a possible method for detection of water microleakages in the cooling system of the first wall and vacuum chamber of ITER. The method consists in the spectroscopic detection of spectral lines of the OH hydroxyl, which forms via the dissociation of water molecules in plasma. Emission in the spectral band of 305–310 nm can be detected even at water leakage rates less than 10 −4 Pa m 3 /s. Chemical reactions between water and boron compounds on the vacuum chamber wall delay the detection of leakages up to ∼2000 s. A similar phenomenon can be expected when a leakage will occur in ITER, where the materials suggested for the first wall (Be, Li) can also chemically react with water.
Acoustic leak detection and ultrasonic crack detection
International Nuclear Information System (INIS)
Kupperman, D.S.; Claytor, T.N.; Groenwald, R.
1983-10-01
A program is under way to assess the effectiveness of current and proposed techniques for acoustic leak detection (ALD) in reactor coolant systems. An ALD facility has been constructed and tests have begun on five laboratory-grown cracks (three fatigue and two thermal-fatigue and two field-induced IGSCC specimens. After ultrasonic testing revealed cracks in the Georgia Power Co. HATCH-1 BWR recirculation header, the utility installed an ALD system. Data from HATCH-1 have given an indication of the background noise level at a BWR recirculation header sweepolet weld. The HATCH leak detection system was tested to determine the sensitivity and dynamic range. Other background data have been acquired at the Watts Bar Nuclear Reactor in Tennessee. An ANL waveguide system, including transducer and electronics, was installed and tested on an accumulator safety injection pipe. The possibility of using ultrasonic wave scattering patterns to discriminate between IGSCCs and geometric reflectors has been explored. Thirteen reflectors (field IGSCCs, graphite wool IGSCCs, weld roots, and slits) were examined. Work with cast stainless steel (SS) included sound velocity and attenuation in isotropic and anisotropic cast SS. Reducing anisotropy does not help reduce attenuation in large-grained material. Large artificial flaws (e.g., a 1-cm-deep notch with a 4-cm path) could not be detected in isotropic centrifugally cast SS (1 to 2-mm grains) by longitudinal or shear waves at frequencies of 1 MHz or greater, but could be detected with 0.5-MHz shear waves. 13 figures
Irii, Toshiaki; Maebashi, Kyoko; Fukui, Kenji; Sohma, Ryoko; Matsumoto, Sari; Takasu, Shojiro; Iwadate, Kimiharu
2016-05-01
Investigation of drug-related crimes, such as violation of the Stimulant Drug Control Law, requires identifying the used drug (mainly stimulant drugs, methamphetamine hydrochloride) from a drug solution and the DNA type of the drug user from a trace of blood left in the syringe used to inject the drug. In current standard test procedures, DNA typing and methamphetamine detection are performed as independent tests that use two separate portions of a precious sample. The sample can be entirely used up by either analysis. Therefore, we developed a new procedure involving partial lysis of a stimulant-containing blood sample followed by separation of the lysate into a precipitate for DNA typing and a liquid-phase fraction for methamphetamine detection. The method enables these two tests to be run in parallel using a single portion of sample. Samples were prepared by adding methamphetamine hydrochloride water solution to blood. Samples were lysed with Proteinase K in PBS at 56°C for 20min, cooled at -20°C after adding methanol, and then centrifuged at 15,000rpm. Based on the biopolymer-precipitating ability of alcohol, the precipitate was used for DNA typing and the liquid-phase fraction for methamphetamine detection. For DNA typing, the precipitate was dissolved and DNA was extracted, quantified, and subjected to STR analysis using the AmpFℓSTR® Identifiler® Plus PCR Amplification Kit. For methamphetamine detection, the liquid-phase fraction was evaporated with N2 gas after adding 20μL acetic acid and passed through an extraction column; the substances captured in the column were eluted with a solvent, derivatized, and quantitatively detected using gas chromatograph/mass spectrometry. This method was simple and could be completed in approximately 2h. Both DNA typing and methamphetamine detection were possible, which suggests that this method may be valuable for use in criminal investigations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Energy Technology Data Exchange (ETDEWEB)
Schreiber, G.A.; Helle, N.; Schulzki, G.; Linke, B.; Spiegelberg, A.; Mager, M.; Boegl, K.W. [BgVV - Federal Inst. for Health Protection of Consumers and Veterinary Medicine, Berlin (Germany)
1996-12-31
The gas chromatographic (GC) analysis of radiation-induced volatile hydrocarbons (HC) and 2-alkylcyclobutanones, the ESR spectroscopic detection of radiation-specific radicals and the thermoluminescence (TL) analysis of silicate mineral are the most important methods for identification of irradiated foods. After successful performance in interlaboratory studies on meat products, fish, spices, herbs and shells of nuts, all or some of these methods have been approved by national authorities in Germany and the United Kingdom. Recently, draft European Standards have been elaborated for approval by member states of the European Committee for Standardization (CEN). Several research laboratories have shown that these methods can be applied to various foods not yet tested in collaborative studies. However, for an effective application in food control it is necessary to prove their suitability in interlaboratory studies. Therefore, in 1993/94, various interlaboratory tests were organised by the BgVV. In an ESR spectroscopic test, shrimps and paprika powder were examined. Shrimps were also the subject of examination in a TL test. Finally, GC detection of radiation-induced hydrocarbons in the fat fraction of foods was used in another test to identify irradiated Camembert, avocado, papaya and mango. In the following paper, results of the interlaboratory tests are summarised. Detailed reports are published by this institute. (author).
International Nuclear Information System (INIS)
Schreiber, G.A.; Helle, N.; Schulzki, G.; Linke, B.; Spiegelberg, A.; Mager, M.; Boegl, K.W.
1996-01-01
The gas chromatographic (GC) analysis of radiation-induced volatile hydrocarbons (HC) and 2-alkylcyclobutanones, the ESR spectroscopic detection of radiation-specific radicals and the thermoluminescence (TL) analysis of silicate mineral are the most important methods for identification of irradiated foods. After successful performance in interlaboratory studies on meat products, fish, spices, herbs and shells of nuts, all or some of these methods have been approved by national authorities in Germany and the United Kingdom. Recently, draft European Standards have been elaborated for approval by member states of the European Committee for Standardization (CEN). Several research laboratories have shown that these methods can be applied to various foods not yet tested in collaborative studies. However, for an effective application in food control it is necessary to prove their suitability in interlaboratory studies. Therefore, in 1993/94, various interlaboratory tests were organised by the BgVV. In an ESR spectroscopic test, shrimps and paprika powder were examined. Shrimps were also the subject of examination in a TL test. Finally, GC detection of radiation-induced hydrocarbons in the fat fraction of foods was used in another test to identify irradiated Camembert, avocado, papaya and mango. In the following paper, results of the interlaboratory tests are summarised. Detailed reports are published by this institute. (author)
Walton, David M; Macdermid, Joy C; Nielson, Warren; Teasell, Robert W; Chiasson, Marco; Brown, Lauren
2011-09-01
Clinical measurement. To evaluate the intrarater, interrater, and test-retest reliability of an accessible digital algometer, and to determine the minimum detectable change in normal healthy individuals and a clinical population with neck pain. Pressure pain threshold testing may be a valuable assessment and prognostic indicator for people with neck pain. To date, most of this research has been completed using algometers that are too resource intensive for routine clinical use. Novice raters (physiotherapy students or clinical physiotherapists) were trained to perform algometry testing over 2 clinically relevant sites: the angle of the upper trapezius and the belly of the tibialis anterior. A convenience sample of normal healthy individuals and a clinical sample of people with neck pain were tested by 2 different raters (all participants) and on 2 different days (healthy participants only). Intraclass correlation coefficient (ICC), standard error of measurement, and minimum detectable change were calculated. A total of 60 healthy volunteers and 40 people with neck pain were recruited. Intrarater reliability was almost perfect (ICC = 0.94-0.97), interrater reliability was substantial to near perfect (ICC = 0.79-0.90), and test-retest reliability was substantial (ICC = 0.76-0.79). Smaller change was detectable in the trapezius compared to the tibialis anterior. This study provides evidence that novice raters can perform digital algometry with adequate reliability for research and clinical use in people with and without neck pain.
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg; Conradsen, Knut; Skriver, Henning
2016-01-01
Based on an omnibus likelihood ratio test statistic for the equality of several variance-covariance matrices following the complex Wishart distribution with an associated p-value and a factorization of this test statistic, change analysis in a short sequence of multilook, polarimetric SAR data...... in the covariance matrix representation is carried out. The omnibus test statistic and its factorization detect if and when change(s) occur. The technique is demonstrated on airborne EMISAR L-band data but may be applied to Sentinel-1, Cosmo-SkyMed, TerraSAR-X, ALOS and RadarSat-2 or other dual- and quad...
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg; Conradsen, Knut; Skriver, Henning
2016-01-01
Based on an omnibus likelihood ratio test statistic for the equality of several variance-covariance matrices following the complex Wishart distribution with an associated p-value and a factorization of this test statistic, change analysis in a short sequence of multilook, polarimetric SAR data...... in the covariance matrix representation is carried out. The omnibus test statistic and its factorization detect if and when change(s) occur. The technique is demonstrated on airborne EMISAR L-band data but may be applied to Sentinel-1, Cosmo-SkyMed, TerraSAR-X, ALOS and RadarSat-2 or other dual- and quad...
Energy Technology Data Exchange (ETDEWEB)
Nolan, J P; Vladutiu, A O; Moreno, D M; Cohen, S A; Camara, D S [State University of New York, Buffalo (USA). School of Medicine
1982-11-26
The ability to measure circulating endotoxin in various disease states has been hampered by the lack of a specific and quantitative assay. The test most commonly used has been the Limulus gelation assay, which measures an enzymatic effect of endotoxin rather than the substance itself. Based on a solid-phase immunoradiometric assay previously developed to detect the specific lipopolysaccharide from Escherichia coli 026, a similar assay has been developed for the lipid A moiety of endotoxins. The assay uses rabbit antibodies to lipid A which do not react with ketodeoxyoctonate, myristic or beta-hydroxymyristic acids, and detects lipid A obtained from endotoxins of various origins after acid hydrolysis of lipopolysaccharide. Experiments in rats given exogenous endotoxin suggest that this assay can be useful for quantitation of bacterial endotoxins in serum and for studying the pathophysiology of experimental endotoxemia.
Segura-Ortí, Eva; Martínez-Olmos, Francisco José
2011-08-01
Determining the relative and absolute reliability of outcomes of physical performance tests for people undergoing hemodialysis is necessary to discriminate between the true effects of exercise interventions and the inherent variability of this cohort. The aims of this study were to assess the relative reliability of sit-to-stand-to-sit tests (the STS-10, which measures the time [in seconds] required to complete 10 full stands from a sitting position, and the STS-60, which measures the number of repetitions achieved in 60 seconds), the Six-Minute Walk Test (6MWT), the one-leg heel-rise test, and the handgrip strength test and to calculate minimal detectable change (MDC) scores in people undergoing hemodialysis. This study was a prospective, nonexperimental investigation. Thirty-nine people undergoing hemodialysis at 2 clinics in Spain were contacted. Study participants performed the STS-10 (n=37), the STS-60 (n=37), and the 6MWT (n=36). At one of the settings, the participants also performed the one-leg heel-rise test (n=21) and the handgrip strength test (n=12) on both the right and the left sides. Participants attended 2 testing sessions 1 to 2 weeks apart. High intraclass correlation coefficients (≥.88) were found for all tests, suggesting good relative reliability. The MDC scores at 90% confidence intervals were as follows: 8.4 seconds for the STS-10, 4 repetitions for the STS-60, 66.3 m for the 6MWT, 3.4 kg for handgrip strength (force-generating capacity), 3.7 repetitions for the one-leg heel-rise test with the right leg, and 5.2 repetitions for the one-leg heel-rise test with the left leg. Limitations A limited sample of patients was used in this study. The STS-16, STS-60, 6MWT, one-leg heel rise test, and handgrip strength test are reliable outcome measures. The MDC scores at 90% confidence intervals for these tests will help to determine whether a change is due to error or to an intervention.
Madsen, Tanja; Christensen, Mads; Sloth Andersen, Camilla; Varhelyi, Andras; Laureshyn, Aliaksei; Moeslund, Thomas; Lahrmann, Harry
2017-01-01
Naturalistic studies can potentially be used to detect accidents of vulnerable road users and thus overcome the large degree of under-reporting in the official accident records. In this study, simulated cycling and walking accidents were performed by a stuntman and with a crash test dummy to test how they differ from each other and the potential implications of using simulated accidents as an alternative to real accidents. The study consisted of simulations of common accident types for cyclis...
Diagnostic validation of three test methods for detection of cyprinid herpesvirus 3 (CyHV-3).
Clouthier, Sharon C; McClure, Carol; Schroeder, Tamara; Desai, Megan; Hawley, Laura; Khatkar, Sunita; Lindsay, Melissa; Lowe, Geoff; Richard, Jon; Anderson, Eric D
2017-03-06
Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of koi herpesvirus disease in koi and common carp. The disease is notifiable to the World Organisation for Animal Health. Three tests-quantitative polymerase chain reaction (qPCR), conventional PCR (cPCR) and virus isolation by cell culture (VI)-were validated to assess their fitness as diagnostic tools for detection of CyHV-3. Test performance metrics of diagnostic accuracy were sensitivity (DSe) and specificity (DSp). Repeatability and reproducibility were measured to assess diagnostic precision. Estimates of test accuracy, in the absence of a gold standard reference test, were generated using latent class models. Test samples originated from wild common carp naturally exposed to CyHV-3 or domesticated koi either virus free or experimentally infected with the virus. Three laboratories in Canada participated in the precision study. Moderate to high repeatability (81 to 99%) and reproducibility (72 to 97%) were observed for the qPCR and cPCR tests. The lack of agreement observed between some of the PCR test pair results was attributed to cross-contamination of samples with CyHV-3 nucleic acid. Accuracy estimates for the PCR tests were 99% for DSe and 93% for DSp. Poor precision was observed for the VI test (4 to 95%). Accuracy estimates for VI/qPCR were 90% for DSe and 88% for DSp. Collectively, the results show that the CyHV-3 qPCR test is a suitable tool for surveillance, presumptive diagnosis and certification of individuals or populations as CyHV-3 free.
He, J X; Jiang, Y F
2017-08-06
Hereditary cancer is caused by specific pathogenic gene mutations. Early detection and early intervention are the most effective ways to prevent and control hereditary cancer. High-throughput sequencing based genetic testing technology (NGS) breaks through the restrictions of pedigree analysis, provide a convenient and efficient method to detect and diagnose hereditary cancer. Here, we introduce the mechanism of hereditary cancer, summarize, discuss and prospect the application of NGS and other genetic tests in the diagnosis of hereditary retinoblastoma, hereditary breast and ovarian cancer syndrome, hereditary colorectal cancer and other complex and rare hereditary tumors.
Test sensitivity is important for detecting variability in pointing comprehension in canines.
Pongrácz, Péter; Gácsi, Márta; Hegedüs, Dorottya; Péter, András; Miklósi, Adám
2013-09-01
Several articles have been recently published on dogs' (Canis familiaris) performance in two-way object choice experiments in which subjects had to find hidden food by utilizing human pointing. The interpretation of results has led to a vivid theoretical debate about the cognitive background of human gestural signal understanding in dogs, despite the fact that many important details of the testing method have not yet been standardized. We report three experiments that aim to reveal how some procedural differences influence adult companion dogs' performance in these tests. Utilizing a large sample in Experiment 1, we provide evidence that neither the keeping conditions (garden/house) nor the location of the testing (outdoor/indoor) affect a dogs' performance. In Experiment 2, we compare dogs' performance using three different types of pointing gestures. Dogs' performance varied between momentary distal and momentary cross-pointing but "low" and "high" performer dogs chose uniformly better than chance level if they responded to sustained pointing gestures with reinforcement (food reward and a clicking sound; "clicker pointing"). In Experiment 3, we show that single features of the aforementioned "clicker pointing" method can slightly improve dogs' success rate if they were added one by one to the momentary distal pointing method. These results provide evidence that although companion dogs show a robust performance at different testing locations regardless of their keeping conditions, the exact execution of the human gesture and additional reinforcement techniques have substantial effect on the outcomes. Consequently, researchers should standardize their methodology before engaging in debates on the comparative aspects of socio-cognitive skills because the procedures they utilize may differ in sensitivity for detecting differences.
Temperature Trend Detection in Upper Indus Basin by Using Mann-Kendall Test
Directory of Open Access Journals (Sweden)
Ateeq Ur Rauf
2016-10-01
Full Text Available Global warming and Climate change are commonly acknowledged as the most noteworthy environmental quandary the world is undergoing today. Contemporary studies have revealed that the Earth’s surface air temperature has augmented by 0.6°C – 0.8°C in the course of the 20th century, together with alterations in the hydrological cycle. This study focuses on detecting trends in seasonal temperature for the five selected stations in the Upper Indus Basin. The Mann-Kendall test was run at 5% significance level on time series data for each of the five stations during the time period, 1985 to 2014. The Standard Test Statistic (Zs indicates the presence of trend and whether it is increasing or decreasing. The analysis showed an increasing trend in mean monthly temperature at Astore, Gilgit and Gupiz in March and a decreasing trend for Astore, Drosh, Gilgit and Skardu in September. Gilgit and Gupiz showed unexpected increasing trend in October. This study concludes that the temperature starts increasing in March and stays elevated till the month of June and starts rising again in October thus resulting in expansion of summer season and prolonged glacial melting.
Beltrán, M C; Romero, T; Althaus, R L; Molina, M P
2013-05-01
The Charm maximum residue limit β-lactam and tetracycline test (Charm MRL BLTET; Charm Sciences Inc., Lawrence, MA) is an immunoreceptor assay utilizing Rapid One-Step Assay lateral flow technology that detects β-lactam or tetracycline drugs in raw commingled cow milk at or below European Union maximum residue levels (EU-MRL). The Charm MRL BLTET test procedure was recently modified (dilution in buffer and longer incubation) by the manufacturers to be used with raw ewe and goat milk. To assess the Charm MRL BLTET test for the detection of β-lactams and tetracyclines in milk of small ruminants, an evaluation study was performed at Instituto de Ciencia y Tecnologia Animal of Universitat Politècnica de València (Spain). The test specificity and detection capability (CCβ) were studied following Commission Decision 2002/657/EC. Specificity results obtained in this study were optimal for individual milk free of antimicrobials from ewes (99.2% for β-lactams and 100% for tetracyclines) and goats (97.9% for β-lactams and 100% for tetracyclines) along the entire lactation period regardless of whether the results were visually or instrumentally interpreted. Moreover, no positive results were obtained when a relatively high concentration of different substances belonging to antimicrobial families other than β-lactams and tetracyclines were present in ewe and goat milk. For both types of milk, the CCβ calculated was lower or equal to EU-MRL for amoxicillin (4 µg/kg), ampicillin (4 µg/kg), benzylpenicillin (≤ 2 µg/kg), dicloxacillin (30 µg/kg), oxacillin (30 µg/kg), cefacetrile (≤ 63 µg/kg), cefalonium (≤ 10 µg/kg), cefapirin (≤ 30 µg/kg), desacetylcefapirin (≤ 30 µg/kg), cefazolin (≤ 25 µg/kg), cefoperazone (≤ 25 µg/kg), cefquinome (20 µg/kg), ceftiofur (≤ 50 µg/kg), desfuroylceftiofur (≤ 50µg/kg), and cephalexin (≤ 50 µg/kg). However, this test could neither detect cloxacillin nor nafcillin at or below EU-MRL (CCβ >30 µg/kg). The
Ausab test - a radioimmunoassay in the solid phase for the detection of antibodies against HBsAg
Energy Technology Data Exchange (ETDEWEB)
Lange, W; Koehler, H; Apodaca, J [Bundesgesundheitsamt, Berlin (Germany, F.R.). Abt. fuer Virologie
1974-01-01
The suitability of a newly developed RIA (Ausab test, Abbott laboratories) for the detection of antibodies against the Hepatitis B (surface) antigen (HBsAg) has been tested on 1968 sera of blood donors. Reproducibility test and specificity test were included. During the examination the technique of the Ausab test was changed from the original one-step to the two-step procedure. With the one-step technique 431 of 1968 sera (21.9%) showed positive reactions. During the test problems concerning the differentiation between positive and negative results were encountered due to high unspecific binding of radioactivity. Positive sera were re-examined employing the two-step technique and only 77.4% of the previously positive reactions could be reproduced. 50 sera that were negative in the one-step test remained negative in the two-step test. Difficulties concerning nonspecific binding of radioactivity as observed with the one-step technique were not encountered with the two-step procedure. On 92 of the confirmed positive sera a specificity test was run and 90 (97.8%) proved to be specific. A calculated 16.5% of the blood donors in Berlin have to be considered as antibody carriers. Only 6 of the Ausab positive sera were found to give positive reactions in CEP. 3 sera that were initially positive in CEP could neither be confirmed in a repeated CEP nor in the Ausab test.
The DNA comet assay and the germination test in detection of food treated by ionizing radiation
International Nuclear Information System (INIS)
Huachaca, Nelida Simona Marin
2002-01-01
Two methods of irradiated food detection, one biochemical, the comet assay and, other biological, the germination test, were applied in bovine meat and fruit samples. The comet assay detects the damage on DNA caused by ionizing radiation. The germination test evaluates the sensitivity to radiation of seeds as for germination ability, shooting and, rooting. The samples were irradiated in gamma font and electron accelerator. For bovine meat samples, the doses were 0.0; 2.5; 4.5 e 7.0 kGy at chilled condition and, 0.0; 2.5; 4.5; 7.0 e 8.5 kGy at frozen conditions. For fruit samples such as melon, watermelon, apple, orange, papaya and, tomato, the doses were: 0.0; 0.5; 0.75; 1.0; 2.0 e 4.0 kGy. The differences between the gamma rays and the electron beam effects on extent of DNA migration and, on shooting and rooting, showed to be similar. The comet assay, under neutral conditions, permitted to discriminate between irradiated and unirradiated bovine meat samples, until one month of storage. Also, it was possible to distinguish, by the comet assay, the control sample with regard to irradiated fruit, at doses as low as 0,5 kGy. In the germination test, the root length was the best parameter to discriminate irradiated and unirradiated samples of melon, watermelon and tomato, while the germination percent was the best parameter for apple and orange. (author)
Howell, David R; Osternig, Louis R; Chou, Li-Shan
2018-02-16
To examine the acute (within 72h of injury) and long-term (2mo postinjury) independent associations between objective dual-task gait balance and neurocognitive measurements among adolescents and young adults with a concussion and matched controls. Longitudinal case-control. Motion analysis laboratory. A total of 95 participants completed the study: 51 who sustained a concussion (mean age, 17.5±3.3y; 71% men) and 44 controls (mean age, 17.7±2.9y; 72% men). Participants who sustained a concussion underwent a dual-task gait analysis and computerized neurocognitive testing within 72 hours of injury and again 2 months later. Uninjured controls also completed the same test protocol in similar time increments. Not applicable. We compared dual-task gait balance control and computerized neurocognitive test performance between groups using independent samples t tests. Multivariable binary logistic regression models were then constructed for each testing time to determine the association between group membership (concussion vs control), dual-task gait balance control, and neurocognitive function. Medial-lateral center-of-mass displacement during dual-task gait was independently associated with group membership at the initial test (adjusted odds ratio [aOR], 2.432; 95% confidence interval [CI], 1.269-4.661) and 2-month follow-up test (aOR, 1.817; 95% CI, 1.014-3.256) tests. Visual memory composite scores were significantly associated with group membership at the initial hour postinjury time point (aOR, .953; 95% CI, .833-.998). However, the combination of computerized neurocognitive test variables did not predict dual-task gait balance control for participants with concussion, and no single neurocognitive variable was associated with dual-task gait balance control at either testing time. Dual-task assessments concurrently evaluating gait and cognitive performance may allow for the detection of persistent deficits beyond those detected by computerized neurocognitive deficits
Dawnay, Nick; Hughes, Rebecca; Court, Denise Syndercombe; Duxbury, Nicola
2016-01-01
Identifying individual species or determining species' composition in an unknown sample is important for a variety of forensic applications. Food authentication, monitoring illegal trade in endangered species, forensic entomology, sexual assault case work and counter terrorism are just some of the fields that can require the detection of the biological species present. Traditional laboratory based approaches employ a wide variety of tools and technologies and exploit a number of different species specific traits including morphology, molecular differences and immuno-chemical analyses. A large number of these approaches require laboratory based apparatus and results can take a number of days to be returned to investigating authorities. Having a presumptive test for rapid identification could lead to savings in terms of cost and time and allow sample prioritisation if confirmatory testing in a laboratory is required later. This model study describes the development of an assay using a single HyBeacon(®) probe and melt curve analyses allowing rapid screening and authentication of food products labelled as Atlantic cod (Gadus morhua). Exploiting melt curve detection of species specific SNP sites on the COI gene the test allows detection of a target species (Atlantic cod) and closely related species which may be used as substitutes. The assay has been designed for use with the Field Portable ParaDNA system, a molecular detection platform for non-expert users. The entire process from sampling to result takes approximately 75min. Validation studies were performed on both single source genomic DNA, mixed genomic DNA and commercial samples. Data suggests the assay has a lower limit of detection of 31 pg DNA. The specificity of the assay to Atlantic cod was measured by testing highly processed food samples including frozen, defrosted and cooked fish fillets as well as fish fingers, battered fish fillet and fish pie. Ninety-six (92.7%) of all Atlantic cod food products
Directory of Open Access Journals (Sweden)
David J Moore
Full Text Available HIV-associated neurocognitive disorders (HAND remain prevalent despite improved antiretroviral treatment (ART, and it is essential to have a sensitive and specific HAND screening tool.Participants were 200 HIV-infected US military beneficiaries, managed early in the course of HIV infection, had few comorbidities, and had open access to ART. Participants completed a comprehensive, seven-domain (16-test, neuropsychological battery (∼120 min; neurocognitive impairment (NCI was determined using a standardized score derived from demographically adjusted T-scores (global deficit score ≥0.5. Restricting the estimated administration time of the screening battery to < = 20 minutes, we examined the sensitivity and specificity of detecting NCI for all possible combinations of 2-, 3-, and 4- tests from the comprehensive battery.Participants were relatively healthy (median CD4 count: 546 cells/mm(3 with 64% receiving ART. Prevalence of NCI was low (19%. The best 2-test screener included the Stroop Color Test and the Hopkins Verbal Learning Test-Revised (11 min; sensitivity = 73%; specificity = 83%; the best 3-test screener included the above measures plus the Paced Auditory Serial Addition Test (PASAT; 16 min; sensitivity = 86%; specificity = 75%. The addition of Action Fluency to the above three tests improved specificity (18 min; sensitivity = 86%; specificity = 87%.Combinations of widely accepted neuropsychological tests with brief implementation time demonstrated good sensitivity and specificity compared to a time intensive neuropsychological test battery. Tests of verbal learning, attention/working memory, and processing speed are particularly useful in detecting NCI. Utilizing validated, easy to administer, traditional neuropsychological tests with established normative data may represent an excellent approach to screening for NCI in HIV.
Directory of Open Access Journals (Sweden)
Shifra Ken Dror
Full Text Available Infectious gastroenteritis is a global health problem associated with high morbidity and mortality rates. Rapid and accurate diagnosis is crucial to allow appropriate and timely treatment. Current laboratory stool testing has a long turnaround time (TAT and demands highly qualified personnel and multiple techniques. The need for high throughput and the number of possible enteric pathogens compels the implementation of a molecular approach which uses multiplex technology, without compromising performance requirements. In this work we evaluated the feasibility of the NanoCHIP® Gastrointestinal Panel (GIP (Savyon Diagnostics, Ashdod, IL, a molecular microarray-based screening test, to be used in the routine workflow of our laboratory, a big outpatient microbiology laboratory. The NanoCHIP® GIP test provides simultaneous detection of nine major enteric bacteria and parasites: Campylobacter spp., Salmonella spp., Shigella spp., Giardia sp., Cryptosporidium spp., Entamoeba histolytica, Entamoeba dispar, Dientamoeba fragilis, and Blastocystis spp. The required high-throughput was obtained by the NanoCHIP® detection system together with the MagNA Pure 96 DNA purification system (Roche Diagnostics Ltd., Switzerland. This combined system has demonstrated a higher sensitivity and detection yield compared to the conventional methods in both, retrospective and prospective samples. The identification of multiple parasites and bacteria in a single test also enabled increased efficiency of detecting mixed infections, as well as reduced hands-on time and work load. In conclusion, the combination of these two automated systems is a proper response to the laboratory needs in terms of improving laboratory workflow, turn-around-time, minimizing human errors and can be efficiently integrated in the routine work of the laboratory.
International Nuclear Information System (INIS)
Douglas, D.G.; Starr, J.W.; Juliano, T.M.; Maresca, J.W. Jr.
1993-09-01
This document provides a detailed leak detection test plan and schedule for leak testing many of the pipelines that comprise the active portion of the liquid low-level waste (LLLW) system at the Oak Ridge National Laboratory (ORNL). This plan was prepared in response to the requirements of the Federal Facility Agreement (FFA) between the US Department of Energy (DOE) and two other agencies, the US Environmental Protection Agency (EPA) and the Tennessee Department of Environment and Conservation (TDEC). The LLLW system is an interconnected complex of tanks and pipelines. The FFA distinguishes four categories of tank and pipeline systems within this complex: new systems (Category A), doubly contained systems (Category B), singly contained systems (Category C), and inactive systems (Category D). The FFA specifically requires leak testing of the Category C systems. This plan and schedule addresses leak testing of the Category C pipelines and those doubly contained pipelines that do not fully meet the requirements for secondary containment as listed in the FFA
Detection of antigens of allergic diseases in children by radioallergosorbent test (RAST), 1
International Nuclear Information System (INIS)
Hirooka, Junko
1977-01-01
Detection of antigens mainly by RAST, measurement of immunoglobulin, and investigation of clinical history were performed on children with intractable bronchial asthma. The results were compared with those in cases of mild or moderate degree, and they were discussed. The obtained results were as follows: 1) Cases, of which the occurrence age of disease was under 2 years old, hold a majority in intractable cases, and the ratio was twice that of the control group. 2) A result of skin test was generally lower positive rate in the intractable group as compared to the control group. However, a result of prick test for buckwheat antigen in the intractable group showed higher positive rate than that in the control group. The intractable group tended to be separated into two extreme groups, one which showed positive to most of inhaled antigens in skin test, and another which showed negative to all antigens. 3) As a result of RAST, 13% of the intractable group showed positive to egg white out of food antigens, and it was three times the ratio of positive in the control group. One case showed strong positive to rice. 4) Two thirds of cases which showed positive in RAST for food antigens showed negative in prick test. 5) Total IgE in the serum of the intractable group was clearly lower in values than that of the control group. (Tsunoda, M.)
Directory of Open Access Journals (Sweden)
Daria Štefatić
2008-08-01
Full Text Available Colorectal cancer is one of the most common cancer types worldwide and it continues to be a serious public health problem. Early detection and diagnosis are of great importance in cancer management. At present, diagnostic blood tests are based on the detection of tumor-associated markers such as carcinoembryonic antigen (CEA, the cancer antigen CA19-9 for gastrointestinal cancer, CA15-3 for breast cancer or CA125 for ovarian cancer. The lack of sensitivity and specificity of these markers prevents their general use in cancer screening of an average risk population. Therefore, new cancer biomarkers or better screening methods are necessary to improve the diagnostics of the disease. This study was directed to the optimization of a diagnostic, enzyme linked immunosorbent assay (ELISA based test to identify and validate new serum markers, such as extracellular Protein Kinase A (ecPKA and Nicotinamide A-Meth- yltransferase (NNMT. In this type of assay, the cancer antigens are quantified indirectly - by detecting the presence of auto-antibodies against tumor proteins in human serum. The result of the optimization and validation process was in the case of ecPKA a reproducible and stable assay. In case of NNMT the assay was probably not sensitive enough.
International Nuclear Information System (INIS)
Tomka, M.; Kirchhoff, T.; Stefurkova, V.; Zajac, V.; Kulcsar, L.
1998-01-01
Familial adenomatous polyposis (FAP) is usually associated with mutation in the adenomatous polyposis coli (APC) gene. To examine the occurrence of these mutations in the number of FAP suspected families from the whole Slovakia effectively, we have applied heteroduplex analysis (HDA) and protein truncation test (PTT) for the analyses of 2-5 base pair deletions and point mutations of the APC gene. In the analyzed exon 15 of the APC gene determined by the primers 15Efor-15Grev for HDA and 15ET7-15J3 for PTT more than 70% of mutations should be deletions [3, 12], which are detectable by HDA. In our collection of 5 FAP families mutations in the APC gene were found in families 10, 27 and 41 using HDA. By PTT test the formation of truncated APC protein in FAP families 2, 10, 16 and 27 were revealed. The necessity of combination of at least HDA and PTT techniques for exact detection of APC mutations in analyzed APC region is discussed. (authors)
Trace Contraband Detection Field-Test by the South Texas Specialized Crimes and Narcotics Task Force
Energy Technology Data Exchange (ETDEWEB)
Hannum, David W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Contraband Detection Dept.; Shannon, Gary W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Contraband Detection Dept.
2006-04-01
This report describes the collaboration between the South Texas Specialized Crimes and Narcotics Task Force (STSCNTF) and Sandia National Laboratories (SNL) in a field test that provided prototype hand-held trace detection technology for use in counter-drug operations. The National Institute of Justice (NIJ)/National Law Enforcement and Corrections Technology Center (NLECTC)/Border Research and Technology Center (BRTC) was contacted by STSCNTF for assistance in obtaining cutting-edge technology. The BRTC created a pilot project for Sandia National Laboratories (SNL) and the STSCNTF for the use of SNL’s Hound, a hand-held sample collection and preconcentration system that, when combined with a commercial chemical detector, can be used for the trace detection of illicit drugs and explosives. The STSCNTF operates in an area of high narcotics trafficking where methods of concealment make the detection of narcotics challenging. Sandia National Laboratories’ (SNL) Contraband Detection Department personnel provided the Hound system hardware and operational training. The Hound system combines the GE VaporTracer2, a hand-held commercial chemical detector, with an SNL-developed sample collection and preconcentration system. The South Texas Task force reported a variety of successes, including identification of a major shipment of methamphetamines, the discovery of hidden compartments in vehicles that contained illegal drugs and currency used in drug deals, and the identification of a suspect in a nightclub shooting. The main advantage of the hand-held trace detection unit is its ability to quickly identify the type of chemical (drugs or explosives) without a long lag time for laboratory analysis, which is the most common analysis method for current law enforcement procedures.
Energy Technology Data Exchange (ETDEWEB)
Budal, Elisabeth B; Haugland, Hans K; Skar, Robert [Department of Pathology, Haukeland University Hospital, N-2021, Bergen (Norway); Mæhle, Bjørn O [Department of Pathology, Haukeland University Hospital, N-2021, Bergen (Norway); Section for Pathology, Department of Clinical Medicine, University of Bergen, N-5021, Bergen (Norway); Bjørge, Tone [Department of Global Public Health and Primary Care, University of Bergen, Bergen (Norway); Norwegian Institute of Public Health, Bergen (Norway); Vintermyr, Olav K, E-mail: olav.vintermyr@helse-bergen.no [Department of Pathology, Haukeland University Hospital, N-2021, Bergen (Norway); Section for Pathology, Department of Clinical Medicine, University of Bergen, N-5021, Bergen (Norway)
2014-02-01
In Norway, Pap smears with atypical squamous cells of uncertain significance (ASCUS) and low-grade squamous intraepithelial lesions (LSIL) are triaged after 6 months. The aim of the study was to evaluate effects of implementing human papillomavirus (HPV) test (2005) in delayed triage of ASCUS and LSIL in a cohort of women from Western Norway. After a survey of 119,469 cervical Pap smears during 2005–2007, a total of 1055 women with an index ASCUS or LSIL were included in the study and followed up for 3–6 years with respect to progression into cervical intraepithelial neoplasia grade 2 or worse (CIN2+). Overall sensitivity for detection of CIN2+ with HPV testing and cytology was 96% and 72%, respectively. The sensitivity for detection of CIN2+ was not affected by age, but the specificity of the HPV test increased with age. Thus, for the age groups <34 years, 34–50 years, and >50 years, the specificity of a positive HPV test to detect CIN2+ was 47%, 71%, and 82%, respectively. Positive predictive values for CIN2+ in women with positive cytology, positive HPV test, negative cytology, negative HPV test, or negative HPV and cytology tests were 52%, 41%, 8%, 1.5%, and 0.4%, respectively. HPV testing resulted in a net 22% increased detection of CIN2+. Fifty-six percent of CIN2+ was detected at an earlier time point with HPV testing in triage. Implementation of HPV testing in delayed triage of ASCUS and LSIL improved the stratification of CIN2+ risk and increased CIN2+ detection and at an earlier time point than with triage by cytology alone.
Budal, Elisabeth B; Haugland, Hans K; Skar, Robert; Maehle, Bjørn O; Bjørge, Tone; Vintermyr, Olav K
2014-02-01
In Norway, Pap smears with atypical squamous cells of uncertain significance (ASCUS) and low-grade squamous intraepithelial lesions (LSIL) are triaged after 6 months. The aim of the study was to evaluate effects of implementing human papillomavirus (HPV) test (2005) in delayed triage of ASCUS and LSIL in a cohort of women from Western Norway. After a survey of 119,469 cervical Pap smears during 2005-2007, a total of 1055 women with an index ASCUS or LSIL were included in the study and followed up for 3-6 years with respect to progression into cervical intraepithelial neoplasia grade 2 or worse (CIN2+). Overall sensitivity for detection of CIN2+ with HPV testing and cytology was 96% and 72%, respectively. The sensitivity for detection of CIN2+ was not affected by age, but the specificity of the HPV test increased with age. Thus, for the age groups 50 years, the specificity of a positive HPV test to detect CIN2+ was 47%, 71%, and 82%, respectively. Positive predictive values for CIN2+ in women with positive cytology, positive HPV test, negative cytology, negative HPV test, or negative HPV and cytology tests were 52%, 41%, 8%, 1.5%, and 0.4%, respectively. HPV testing resulted in a net 22% increased detection of CIN2+. Fifty-six percent of CIN2+ was detected at an earlier time point with HPV testing in triage. Implementation of HPV testing in delayed triage of ASCUS and LSIL improved the stratification of CIN2+ risk and increased CIN2+ detection and at an earlier time point than with triage by cytology alone. © 2013 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.
International Nuclear Information System (INIS)
Budal, Elisabeth B; Haugland, Hans K; Skar, Robert; Mæhle, Bjørn O; Bjørge, Tone; Vintermyr, Olav K
2014-01-01
In Norway, Pap smears with atypical squamous cells of uncertain significance (ASCUS) and low-grade squamous intraepithelial lesions (LSIL) are triaged after 6 months. The aim of the study was to evaluate effects of implementing human papillomavirus (HPV) test (2005) in delayed triage of ASCUS and LSIL in a cohort of women from Western Norway. After a survey of 119,469 cervical Pap smears during 2005–2007, a total of 1055 women with an index ASCUS or LSIL were included in the study and followed up for 3–6 years with respect to progression into cervical intraepithelial neoplasia grade 2 or worse (CIN2+). Overall sensitivity for detection of CIN2+ with HPV testing and cytology was 96% and 72%, respectively. The sensitivity for detection of CIN2+ was not affected by age, but the specificity of the HPV test increased with age. Thus, for the age groups <34 years, 34–50 years, and >50 years, the specificity of a positive HPV test to detect CIN2+ was 47%, 71%, and 82%, respectively. Positive predictive values for CIN2+ in women with positive cytology, positive HPV test, negative cytology, negative HPV test, or negative HPV and cytology tests were 52%, 41%, 8%, 1.5%, and 0.4%, respectively. HPV testing resulted in a net 22% increased detection of CIN2+. Fifty-six percent of CIN2+ was detected at an earlier time point with HPV testing in triage. Implementation of HPV testing in delayed triage of ASCUS and LSIL improved the stratification of CIN2+ risk and increased CIN2+ detection and at an earlier time point than with triage by cytology alone
Madsen, Tanja Kidholm Osmann; Christensen, Mads Bock; Andersen, Camilla Sloth; Várhelyi, András; Laureshyn, Aliaksei; Moeslund, Thomas B.; Lahrmann, Harry Spaabæk
2017-01-01
Naturalistic studies can potentially be used to detect accidents of vulnerable road users and thus overcome the large degree of under-reporting in the official accident records. In this study, simulated cycling and walking accidents were performed by a stunt man and with a crash test dummy to test how they differ from each other and the potential implications of using simulated accidents as an alternative to real accidents. The study consisted of simulations of common accident types for cycli...
Improving Detection of Prediabetes in Children and Adults: Using Combinations of Blood Glucose Tests
Directory of Open Access Journals (Sweden)
Ike Solomon Okosun
2015-11-01
Full Text Available Aim: To determine combinations of blood glucose tests: oral glucose tolerance (OGT, fasting plasma glucose (FBG and hemoglobin A1C (HbA1C that are associated with highest diagnostic rates of prediabetes in non-diabetic American children and adults.Methods: The 2007-2008 U.S. National Health and Nutrition Examination Surveys data were used for this study. Overall and specific prevalence of prediabetes (defined using OGT+FPG, OGT+HbA1C, HbA1C+FPG and OGT+FPG+HbA1C tests were determined across age, race/ethnicity, sex and BMI categories.Results: FPG+HbA1C test was associated with significantly higher diagnostic rates of prediabetes across age, race/ethnicity and BMI. Estimates of overall prevalence of prediabetes using OGT+FPG, OGT+HbA1C, HbA1C+FPG and OGT+FPG+HbA1C tests were 20.3%, 24.2%, 33% and 34.3%, respectively. Compared to OGT+FPG, the use of HbA1C+FPG test in screening was associated with 44.8%, 135%, 38.6% and 35.9% increased prevalence of prediabetes in non-Hispanic White, non-Hispanic Black, Mexican-American and other racial/ethnic men, respectively. The corresponding values in women were 67.8%, 140%, 37.2% and 42.6%, respectively. Combined use of all blood glucose tests did not improve the overall and gender-specific prediabetes prevalence beyond what was observed using HbA1C+FPG test.Conclusions: HbA1C criteria were associated with higher diagnosis rates of prediabetes than FPG and OGT tests in non-diabetic American children and adults. Using a combination of HbA1C and FPG test in screening for prediabetes reduces intrinsic systematic bias in using just HbA1C testing and offers the benefits of each test. A well-defined HbA1C that takes into consideration race/ethnicity, gender, age and body mass index may improve detection of prediabetes in population and clinical settings.
Tseng, Shao-Chin; Yu, Chen-Chieh; Wan, Dehui; Chen, Hsuen-Li; Wang, Lon Alex; Wu, Ming-Chung; Su, Wei-Fang; Han, Hsieh-Cheng; Chen, Li-Chyong
2012-06-05
Convenient, rapid, and accurate detection of chemical and biomolecules would be a great benefit to medical, pharmaceutical, and environmental sciences. Many chemical and biosensors based on metal nanoparticles (NPs) have been developed. However, as a result of the inconvenience and complexity of most of the current preparation techniques, surface plasmon-based test papers are not as common as, for example, litmus paper, which finds daily use. In this paper, we propose a convenient and practical technique, based on the photothermal effect, to fabricate the plasmonic test paper. This technique is superior to other reported methods for its rapid fabrication time (a few seconds), large-area throughput, selectivity in the positioning of the NPs, and the capability of preparing NP arrays in high density on various paper substrates. In addition to their low cost, portability, flexibility, and biodegradability, plasmonic test paper can be burned after detecting contagious biomolecules, making them safe and eco-friendly.
de Oliveira, Daniele V; Van Der Sand, Sueli T
2016-07-01
Some bacteria from the Enterobacteriaceae family are showing a significant capability to disseminate β-lactams resistance mechanisms among them, and these same mechanisms can be carried out from the hospital environment to superficial water. The aim of this study was to evaluate different phenotypic methods for the detection β-lactamases production by enterobacteria isolated from the anthropogenic environment: hospital wastewater and from a stream that cross the city of Porto Alegre. The applied tests were the modified Hodge test (MHT) and phenotypic tests with the following inhibitors: carbapenemase-phenylboronic acid (APB), metallo-β-lactamase-EDTA, AmpC β-lactamase-cloxacillin, and the confirmatory test for extended-spectrum β-lactamase (ESBL)-clavulanic acid. For this evaluation, 131 isolates were initially subjected to antibiogram using the following antimicrobials: cefotaxime (30 µg), cefpodoxime (10 μg), ceftazidime (30 µg), ertapenem (10 μg), meropenem (10 μg), and aztreonam (30 μg). After this first screening, 62 isolates showed a profile resistance for at least one antimicrobial. These isolates were subjected to all phenotypic tests. Of those, 40 isolates were positive for at least one phenotypic test. In MHT test, one isolate was positive and five were with inconclusive results. The results achieved with the inhibitors are as follows: APB 25/40 positive strains; EDTA 8/40 positive strains; and with CLOXA 2/40 positive strains. ESBL production was observed for 34/40 strains. This assessment shows a high level of bacteria which can produce enzymes that inactivate β-lactams present in the different environment like the stream waters and from the hospital settings.
Directory of Open Access Journals (Sweden)
Aroussi Abdelkrim
2015-01-01
Full Text Available In France, some cases of severe toxoplasmosis have been linked to the consumption of horse meat that had been imported from the American continent where atypical strains of Toxoplasma gondii are more common than in Europe. Many seroprevalence studies are presented in the literature but risk assessment of T. gondii infection after horse meat consumption is not possible in the absence of validated serological tests and the unknown correlation between detection of antibodies against T. gondii and presence of tissue cysts. We performed magnetic-capture polymerase chain reaction (MC-PCR to detect T. gondii DNA in 231 horse meat samples purchased in supermarkets in France and evaluated the performance and level of agreement of the modified agglutination test (MAT and enzyme-linked immunosorbent assay (ELISA in the meat juices. The serological tests lacked sensitivity, specificity, and agreement between them, and there was no correlation with the presence of T. gondii DNA in horse meat, raising concerns about the reliability of T. gondii seroprevalence data in horses from the literature. T. gondii DNA was detected in 43% of horse meat samples but the absence of strain isolation in mice following inoculation of more than 100 horse meat samples suggests a low distribution of cysts in skeletal muscles and a low risk of T. gondii infection associated with horse meat consumption. However, to avoid any risk of toxoplasmosis, thorough cooking of horse meat is recommended.
Aroussi, Abdelkrim; Vignoles, Philippe; Dalmay, François; Wimel, Laurence; Dardé, Marie-Laure; Mercier, Aurélien; Ajzenberg, Daniel
2015-01-01
In France, some cases of severe toxoplasmosis have been linked to the consumption of horse meat that had been imported from the American continent where atypical strains of Toxoplasma gondii are more common than in Europe. Many seroprevalence studies are presented in the literature but risk assessment of T. gondii infection after horse meat consumption is not possible in the absence of validated serological tests and the unknown correlation between detection of antibodies against T. gondii and presence of tissue cysts. We performed magnetic-capture polymerase chain reaction (MC-PCR) to detect T. gondii DNA in 231 horse meat samples purchased in supermarkets in France and evaluated the performance and level of agreement of the modified agglutination test (MAT) and enzyme-linked immunosorbent assay (ELISA) in the meat juices. The serological tests lacked sensitivity, specificity, and agreement between them, and there was no correlation with the presence of T. gondii DNA in horse meat, raising concerns about the reliability of T. gondii seroprevalence data in horses from the literature. T. gondii DNA was detected in 43% of horse meat samples but the absence of strain isolation in mice following inoculation of more than 100 horse meat samples suggests a low distribution of cysts in skeletal muscles and a low risk of T. gondii infection associated with horse meat consumption. However, to avoid any risk of toxoplasmosis, thorough cooking of horse meat is recommended. © A. Aroussi et al., published by EDP Sciences, 2015.
Cohn, T.A.; England, J.F.; Berenbrock, C.E.; Mason, R.R.; Stedinger, J.R.; Lamontagne, J.R.
2013-01-01
he Grubbs-Beck test is recommended by the federal guidelines for detection of low outliers in flood flow frequency computation in the United States. This paper presents a generalization of the Grubbs-Beck test for normal data (similar to the Rosner (1983) test; see also Spencer and McCuen (1996)) that can provide a consistent standard for identifying multiple potentially influential low flows. In cases where low outliers have been identified, they can be represented as “less-than” values, and a frequency distribution can be developed using censored-data statistical techniques, such as the Expected Moments Algorithm. This approach can improve the fit of the right-hand tail of a frequency distribution and provide protection from lack-of-fit due to unimportant but potentially influential low flows (PILFs) in a flood series, thus making the flood frequency analysis procedure more robust.
Directory of Open Access Journals (Sweden)
Mauro Maciel de Arruda
2016-01-01
Full Text Available In Brazil, human and canine visceral leishmaniasis (CVL caused byLeishmania infantum has undergone urbanisation since 1980, constituting a public health problem, and serological tests are tools of choice for identifying infected dogs. Until recently, the Brazilian zoonoses control program recommended enzyme-linked immunosorbent assays (ELISA and indirect immunofluorescence assays (IFA as the screening and confirmatory methods, respectively, for the detection of canine infection. The purpose of this study was to estimate the accuracy of ELISA and IFA in parallel or serial combinations. The reference standard comprised the results of direct visualisation of parasites in histological sections, immunohistochemical test, or isolation of the parasite in culture. Samples from 98 cases and 1,327 noncases were included. Individually, both tests presented sensitivity of 91.8% and 90.8%, and specificity of 83.4 and 53.4%, for the ELISA and IFA, respectively. When tests were used in parallel combination, sensitivity attained 99.2%, while specificity dropped to 44.8%. When used in serial combination (ELISA followed by IFA, decreased sensitivity (83.3% and increased specificity (92.5% were observed. Serial testing approach improved specificity with moderate loss in sensitivity. This strategy could partially fulfill the needs of public health and dog owners for a more accurate diagnosis of CVL.
Tekin, Kemal; Albay, Ali; Simsek, Hulya; Sig, Ali Korhan; Guney, Mustafa
2017-10-01
The present study aimed to evaluate the performances of the BACTEC MGIT 960 SL DST kit and the GenoType MTBDRsl test for detecting second-line antituberculosis drug resistance in Multidrug-resistant TB (MDR-TB) cases. Forty-six MDR-TB strains were studied. Second-line antituberculosis drug resistances were detected using the BACTEC MGIT 960 SL DST kit and the GenoType MTBDRsl test. The Middlebrook 7H10 agar proportion method was used as the reference test. The sensitivity and specificity values for the BACTEC MGIT 960 SL DST kit were both 100% for amikacin, kanamycin, capreomycin (4 µg/mL), and ofloxacin; 100% and 95.3%, respectively, for capreomycin (10 µg/mL); and 85.7% and 100%, respectively, for moxifloxacin (0.5 µg/mL). The sensitivity and specificity values for the GenoType MTBDRsl test to detect fluoroquinolone and aminoglycoside/cyclic peptide resistance were 88.9% and 100%, respectively, for ofloxacin and 85.7% and 94.9%, respectively, for moxifloxacin (0.5 µg/mL). The accuracy of the GenoType MTBDRsl assay for kanamycin, capreomycin, ofloxacin, and moxifloxacin was lower than that of the BACTEC MGIT 960 SL DST. The BACTEC MGIT 960 SL DST kit and the GenoType MTBDRsl were successful in detecting second-line antituberculosis drug resistance. Preliminary results of the GenoType MTBDRsl are very valuable for early treatment decisions, but we still recommend additional BACTEC MGIT 960 SL DST kit usage in the routine evaluation of drug-resistant tuberculosis.
Tekin, Kemal; Albay, Ali; Simsek, Hulya; Sig, Ali Korhan; Guney, Mustafa
2017-01-01
Objective: The present study aimed to evaluate the performances of the BACTEC MGIT 960 SL DST kit and the GenoType MTBDRsl test for detecting second-line antituberculosis drug resistance in Multidrug-resistant TB (MDR-TB) cases. Materials and Methods: Forty-six MDR-TB strains were studied. Second-line antituberculosis drug resistances were detected using the BACTEC MGIT 960 SL DST kit and the GenoType MTBDRsl test. The Middlebrook 7H10 agar proportion method was used as the reference test. Results: The sensitivity and specificity values for the BACTEC MGIT 960 SL DST kit were both 100% for amikacin, kanamycin, capreomycin (4 µg/mL), and ofloxacin; 100% and 95.3%, respectively, for capreomycin (10 µg/mL); and 85.7% and 100%, respectively, for moxifloxacin (0.5 µg/mL). The sensitivity and specificity values for the GenoType MTBDRsl test to detect fluoroquinolone and aminoglycoside/cyclic peptide resistance were 88.9% and 100%, respectively, for ofloxacin and 85.7% and 94.9%, respectively, for moxifloxacin (0.5 µg/mL). The accuracy of the GenoType MTBDRsl assay for kanamycin, capreomycin, ofloxacin, and moxifloxacin was lower than that of the BACTEC MGIT 960 SL DST. Conclusion: The BACTEC MGIT 960 SL DST kit and the GenoType MTBDRsl were successful in detecting second-line antituberculosis drug resistance. Preliminary results of the GenoType MTBDRsl are very valuable for early treatment decisions, but we still recommend additional BACTEC MGIT 960 SL DST kit usage in the routine evaluation of drug-resistant tuberculosis. PMID:29123441
Mandelker, Diana; Zhang, Liying; Kemel, Yelena; Stadler, Zsofia K; Joseph, Vijai; Zehir, Ahmet; Pradhan, Nisha; Arnold, Angela; Walsh, Michael F; Li, Yirong; Balakrishnan, Anoop R; Syed, Aijazuddin; Prasad, Meera; Nafa, Khedoudja; Carlo, Maria I; Cadoo, Karen A; Sheehan, Meg; Fleischut, Megan H; Salo-Mullen, Erin; Trottier, Magan; Lipkin, Steven M; Lincoln, Anne; Mukherjee, Semanti; Ravichandran, Vignesh; Cambria, Roy; Galle, Jesse; Abida, Wassim; Arcila, Marcia E; Benayed, Ryma; Shah, Ronak; Yu, Kenneth; Bajorin, Dean F; Coleman, Jonathan A; Leach, Steven D; Lowery, Maeve A; Garcia-Aguilar, Julio; Kantoff, Philip W; Sawyers, Charles L; Dickler, Maura N; Saltz, Leonard; Motzer, Robert J; O'Reilly, Eileen M; Scher, Howard I; Baselga, Jose; Klimstra, David S; Solit, David B; Hyman, David M; Berger, Michael F; Ladanyi, Marc; Robson, Mark E; Offit, Kenneth
2017-09-05
Guidelines for cancer genetic testing based on family history may miss clinically actionable genetic changes with established implications for cancer screening or prevention. To determine the proportion and potential clinical implications of inherited variants detected using simultaneous sequencing of the tumor and normal tissue ("tumor-normal sequencing") compared with genetic test results based on current guidelines. From January 2014 until May 2016 at Memorial Sloan Kettering Cancer Center, 10 336 patients consented to tumor DNA sequencing. Since May 2015, 1040 of these patients with advanced cancer were referred by their oncologists for germline analysis of 76 cancer predisposition genes. Patients with clinically actionable inherited mutations whose genetic test results would not have been predicted by published decision rules were identified. Follow-up for potential clinical implications of mutation detection was through May 2017. Tumor and germline sequencing compared with the predicted yield of targeted germline sequencing based on clinical guidelines. Proportion of clinically actionable germline mutations detected by universal tumor-normal sequencing that would not have been detected by guideline-directed testing. Of 1040 patients, the median age was 58 years (interquartile range, 50.5-66 years), 65.3% were male, and 81.3% had stage IV disease at the time of genomic analysis, with prostate, renal, pancreatic, breast, and colon cancer as the most common diagnoses. Of the 1040 patients, 182 (17.5%; 95% CI, 15.3%-19.9%) had clinically actionable mutations conferring cancer susceptibility, including 149 with moderate- to high-penetrance mutations; 101 patients tested (9.7%; 95% CI, 8.1%-11.7%) would not have had these mutations detected using clinical guidelines, including 65 with moderate- to high-penetrance mutations. Frequency of inherited mutations was related to case mix, stage, and founder mutations. Germline findings led to discussion or initiation of
International Nuclear Information System (INIS)
Sasahara, Toshihiko
1998-01-01
The present invention provides a device for detecting welded portions of a reactor pressure vessel. Namely, the device of the present invention comprises (1) a casing to be disposed on the surface to be detected, (2) a probe driving means loaded to the casing, (3) a probe driven along the surface to be detected and (4) a pressure reduction means for keeping the hollow portion in the casing to an evacuated atmosphere. The casing comprises a flexible suction edge to be tightly in contact with the surface to be tested for maintaining the air tight state, (6) a guide wheel for moving the casing along the surface to be tested and (7) a handle for performing transferring operation. The flaw detection device thus constituted has following features. The working efficiency upon conducting detection is improved. The influence of the weight of the device on the detection is small. The device can be applied on the surface of a nonmagnetic material. The efficiency for the flaw detection can be improved. (I.S.)
Directory of Open Access Journals (Sweden)
Flávia de Miranda Corrêa
Full Text Available CONTEXT AND OBJECTIVE: The age-stratified performance of the oncogenic HPV-DNA (human papillomavirus deoxyribonucleic acid test for triage of low-grade squamous intraepithelial lesions (LSIL requires investigation. The objective of this study was to evaluate and compare the age-stratified performance (cutoff point: 35 years of oncogenic HPV-DNA testing and repeated cytological tests, for detecting cervical intraepithelial neoplasia grade 3 (CIN3, in order to triage for LSIL. DESIGN AND SETTING: Systematic review. Studies were identified in nine electronic databases and in the reference lists of the articles retrieved. METHODS: The eligibility criteria consisted of initial cytological findings of LSIL; subsequent oncogenic HPV-DNA testing and repeated cytological tests; and CIN3 detection. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS guidelines were used for quality assessment. Qualitative information synthesis was performed. RESULTS: Out of 7,776 studies, 284 were identified as pertinent and three fulfilled the eligibility criteria. The CIN3 prevalence ranged from 6% to 12%. The HPV-DNA positivity rate ranged from 64% to 83%; sensitivity for CIN3 detection ranged from 95.2% to 100%; and specificity was available in two studies (27% and 52%. The sensitivity of repeated cytological tests, in relation to the threshold for atypical squamous cells of undetermined significance (ASCUS, was available in two studies (33% and 90.8%; and specificity was available in one study (53%. CONCLUSIONS: Currently, there is no scientific evidence available that would prove that colposcopic triage using oncogenic HPV-DNA testing to detect CIN3 performs better than repeated cytological tests, among women with LSIL aged 35 years and over.
Statistical theory of signal detection
Helstrom, Carl Wilhelm; Costrell, L; Kandiah, K
1968-01-01
Statistical Theory of Signal Detection, Second Edition provides an elementary introduction to the theory of statistical testing of hypotheses that is related to the detection of signals in radar and communications technology. This book presents a comprehensive survey of digital communication systems. Organized into 11 chapters, this edition begins with an overview of the theory of signal detection and the typical detection problem. This text then examines the goals of the detection system, which are defined through an analogy with the testing of statistical hypotheses. Other chapters consider
Quantitative Ischemia Detection During Cardiac MR Stress Testing
National Research Council Canada - National Science Library
Kraitchman, D
2001-01-01
.... During a second ischemic episode, conventional cine wall motion images were acquired. The time from occlusion to the detection of ischemia by each MR technique, as well as ECG ischemic alterations, was determined...
Chakravorty, Soumitesh; Simmons, Ann Marie; Rowneki, Mazhgan; Parmar, Heta; Cao, Yuan; Ryan, Jamie; Banada, Padmapriya P; Deshpande, Srinidhi; Shenai, Shubhada; Gall, Alexander; Glass, Jennifer; Krieswirth, Barry; Schumacher, Samuel G; Nabeta, Pamela; Tukvadze, Nestani; Rodrigues, Camilla; Skrahina, Alena; Tagliani, Elisa; Cirillo, Daniela M; Davidow, Amy; Denkinger, Claudia M; Persing, David; Kwiatkowski, Robert; Jones, Martin; Alland, David
2017-08-29
The Xpert MTB/RIF assay (Xpert) is a rapid test for tuberculosis (TB) and rifampin resistance (RIF-R) suitable for point-of-care testing. However, it has decreased sensitivity in smear-negative sputum, and false identification of RIF-R occasionally occurs. We developed the Xpert MTB/RIF Ultra assay (Ultra) to improve performance. Ultra and Xpert limits of detection (LOD), dynamic ranges, and RIF-R rpoB mutation detection were tested on Mycobacterium tuberculosis DNA or sputum samples spiked with known numbers of M. tuberculosis H37Rv or Mycobacterium bovis BCG CFU. Frozen and prospectively collected clinical samples from patients suspected of having TB, with and without culture-confirmed TB, were also tested. For M. tuberculosis H37Rv, the LOD was 15.6 CFU/ml of sputum for Ultra versus 112.6 CFU/ml of sputum for Xpert, and for M. bovis BCG, it was 143.4 CFU/ml of sputum for Ultra versus 344 CFU/ml of sputum for Xpert. Ultra resulted in no false-positive RIF-R specimens, while Xpert resulted in two false-positive RIF-R specimens. All RIF-R-associated M. tuberculosis rpoB mutations tested were identified by Ultra. Testing on clinical sputum samples, Ultra versus Xpert, resulted in an overall sensitivity of 87.5% (95% confidence interval [CI], 82.1, 91.7) versus 81.0% (95% CI, 74.9, 86.2) and a sensitivity on sputum smear-negative samples of 78.9% (95% CI, 70.0, 86.1) versus 66.1% (95% CI, 56.4, 74.9). Both tests had a specificity of 98.7% (95% CI, 93.0, 100), and both had comparable accuracies for detection of RIF-R in these samples. Ultra should significantly improve TB detection, especially in patients with paucibacillary disease, and may provide more-reliable RIF-R detection. IMPORTANCE The Xpert MTB/RIF assay (Xpert), the first point-of-care assay for tuberculosis (TB), was endorsed by the World Health Organization in December 2010. Since then, 23 million Xpert tests have been procured in 130 countries. Although Xpert showed high overall sensitivity and
Castells, Antoni; Quintero, Enrique; Álvarez, Cristina; Bujanda, Luis; Cubiella, Joaquín; Salas, Dolores; Lanas, Angel; Carballo, Fernando; Morillas, Juan Diego; Hernández, Cristina; Jover, Rodrigo; Hijona, Elizabeth; Portillo, Isabel; Enríquez-Navascués, José M; Hernández, Vicent; Martínez-Turnes, Alfonso; Menéndez-Villalva, Carlos; González-Mao, Carmen; Sala, Teresa; Ponce, Marta; Andrés, Mercedes; Teruel, Gloria; Peris, Antonio; Sopeña, Federico; González-Rubio, Francisca; Seoane-Urgorri, Agustín; Grau, Jaume; Serradesanferm, Anna; Pozo, Àngels; Pellisé, Maria; Balaguer, Francesc; Ono, Akiko; Cruzado, José; Pérez-Riquelme, Francisco; Alonso-Abreu, Inmaculada; Carrillo-Palau, Marta; de la Vega-Prieto, Mariola; Iglesias, Rosario; Amador, Javier; Blanco, José Manuel; Sastre, Rocio; Ferrándiz, Juan; González-Hernández, Ma José; Andreu, Montserrat; Bessa, Xavier
2014-10-01
We compared the ability of biennial fecal immunochemical testing (FIT) and one-time sigmoidoscopy to detect colon side-specific advanced neoplasms in a population-based, multicenter, nationwide, randomized controlled trial. We identified asymptomatic men and women, 50-69 years old, through community health registries and randomly assigned them to groups that received a single colonoscopy examination or biennial FIT. Sigmoidoscopy yield was simulated from results obtained from the colonoscopy group, according to the criteria proposed in the UK Flexible Sigmoidoscopy Trial for colonoscopy referral. Patients who underwent FIT and were found to have ≥75 ng hemoglobin/mL were referred for colonoscopy. Data were analyzed from 5059 subjects in the colonoscopy group and 10,507 in the FIT group. The main outcome was rate of detection of any advanced neoplasm proximal to the splenic flexure. Advanced neoplasms were detected in 317 subjects (6.3%) in the sigmoidoscopy simulation group compared with 288 (2.7%) in the FIT group (odds ratio for sigmoidoscopy, 2.29; 95% confidence interval, 1.93-2.70; P = .0001). Sigmoidoscopy also detected advanced distal neoplasia in a higher percentage of patients than FIT (odds ratio, 2.61; 95% confidence interval, 2.20-3.10; P = .0001). The methods did not differ significantly in identifying patients with advanced proximal neoplasms (odds ratio, 1.17; 95% confidence interval, 0.78-1.76; P = .44). This was probably due to the lower performance of both strategies in detecting patients with proximal lesions (sigmoidoscopy detected these in 19.1% of patients and FIT in 14.9% of patients) vs distal ones (sigmoidoscopy detected these in 86.8% of patients and FIT in 33.5% of patients). Sigmoidoscopy, but not FIT, detected proximal lesions in lower percentages of women (especially those 50-59 years old) than men. Sigmoidoscopy and FIT have similar limitations in detecting advanced proximal neoplasms, which depend on patients' characteristics
Berchebru, Laurent; Rameil, Pascal; Gaudin, Jean-Christophe; Gausson, Sabrina; Larigauderie, Guilhem; Pujol, Céline; Morel, Yannick; Ramisse, Vincent
2014-10-01
Test and evaluation of engineered biothreat agent detection systems ("biodetectors") are a challenging task for government agencies and industries involved in biosecurity and biodefense programs. In addition to user friendly features, biodetectors need to perform both highly sensitive and specific detection, and must not produce excessive false alerts. In fact, the atmosphere displays a number of variables such as airborne bacterial content that can interfere with the detection process, thus impeding comparative tests when carried out at different times or places. To overcome these bacterial air content fluctuations, a standardized reagent bacterial mixture (SRBM), consisting in a collection of selected cultivable environmental species that are prevalent in temperate climate bioaerosols, was designed to generate a stable, reproducible, and easy to use surrogate of bioaerosol sample. The rationale, design, and production process are reported. The results showed that 8.59; CI 95%: 8.46-8.72 log cfu distributed into vials underwent a 0.95; CI 95%: 0.65-1.26 log viability decay after dehydration and subsequent reconstitution, thus advantageously mimicking a natural bioaerosol sample which is typically composed of cultivable and uncultivable particles. Dehydrated SRBM was stable for more than 12months at 4°C and allowed the reconstitution of a dead/live cells aqueous suspension that is stable for 96h at +4°C, according to plate counts. Specific detection of a simulating biothreat agent (e.g. Bacillus atrophaeus) by immuno-magnetic or PCR assays did not display any significant loss of sensitivity, false negative or positive results in the presence of SRBM. This work provides guidance on testing and evaluating detection devices, and may contribute to the establishment of suitable standards and normalized procedures. Copyright © 2014 Elsevier B.V. All rights reserved.
Latham, S K; Smith, T O
2014-05-01
The purpose of this study was to determine the diagnostic test accuracy of ultrasound for the detection of lateral epicondylitis. An electronic search of databases registering published (MEDLINE, EMBASE, CINAHL, AMED, Cochrane Library, ScienceDirect) and unpublished literature was conducted to January 2013. All diagnostic accuracy studies that compared the accuracy of ultrasound (index test) with a reference standard for lateral epicondylitis were included. The methodological quality of each of the studies was appraised using the QUADAS tool. When appropriate, the pooled sensitivity and specificity analysis was conducted. Ten studies investigating 711 participants and 1077 elbows were included in this review. Ultrasound had variable sensitivity and specificity (sensitivity: 64%-100%; specificity: 36%-100%). The available literature had modest methodological quality, and was limited in terms of sample sizes and blinding between index and reference test results. There is evidence to support the use of ultrasound in the detection of lateral epicondylitis. However, its accuracy appears to be highly dependent on numerous variables, such as operator experience, equipment and stage of pathology. Judgement should be used when considering the benefit of ultrasound for use in clinical practice. Further research assessing variables such a transducer frequency independently is specifically warranted. Level II. Copyright © 2014 Elsevier Masson SAS. All rights reserved.