Aerodynamic Performance of Scale-Model Turbofan Outlet Guide Vanes Designed for Low Noise

NASA Technical Reports Server (NTRS)

Hughes, Christopher E.

2001-01-01

The design of effective new technologies to reduce aircraft propulsion noise is dependent on an understanding of the noise sources and noise generation mechanisms in the modern turbofan engine. In order to more fully understand the physics of noise in a turbofan engine, a comprehensive aeroacoustic wind tunnel test programs was conducted called the 'Source Diagnostic Test.' The text was cooperative effort between NASA and General Electric Aircraft Engines, as part of the NASA Advanced Subsonic Technology Noise Reduction Program. A 1/5-scale model simulator representing the bypass stage of a current technology high bypass ratio turbofan engine was used in the test. The test article consisted of the bypass fan and outlet guide vanes in a flight-type nacelle. The fan used was a medium pressure ratio design with 22 individual, wide chord blades. Three outlet guide vane design configurations were investigated, representing a 54-vane radial Baseline configuration, a 26-vane radial, wide chord Low Count configuration and a 26-vane, wide chord Low Noise configuration with 30 deg of aft sweep. The test was conducted in the NASA Glenn Research Center 9 by 15-Foot Low Speed Wind Tunnel at velocities simulating the takeoff and approach phases of the aircraft flight envelope. The Source Diagnostic Test had several acoustic and aerodynamic technical objectives: (1) establish the performance of a scale model fan selected to represent the current technology turbofan product; (2) assess the performance of the fan stage with each of the three distinct outlet guide vane designs; (3) determine the effect of the outlet guide vane configuration on the fan baseline performance; and (4) conduct detailed flowfield diagnostic surveys, both acoustic and aerodynamic, to characterize and understand the noise generation mechanisms in a turbofan engine. This paper addresses the fan and stage aerodynamic performance results from the Source Diagnostic Test.

Neutral Beam Source and Target Plasma for Development of a Local Electric Field Fluctuation Diagnostic

NASA Astrophysics Data System (ADS)

Bakken, M. R.; Burke, M. G.; Fonck, R. J.; Lewicki, B. T.; Rhodes, A. T.; Winz, G. R.

2016-10-01

A new diagnostic measuring local E-> (r , t) fluctuations is being developed for plasma turbulence studies in tokamaks. This is accomplished by measuring fluctuations in the separation of the π components in the Hα motional Stark spectrum. Fluctuations in this separation are expected to be Ẽ / ẼEMSE 10-3EMSE 10-3 . In addition to a high throughput, high speed spectrometer, the project requires a low divergence (Ω 0 .5°) , 80 keV, 2.5 A H0 beam and a target plasma test stand. The beam employs a washer-stack arc ion source to achieve a high species fraction at full energy. Laboratory tests of the ion source demonstrate repeatable plasmas with Te 10 eV and ne 1.6 ×1017 m-3, sufficient for the beam ion optics requirements. Te and ne scalings of the ion source plasma are presented with respect to operational parameters. A novel three-phase resonant converter power supply will provide 6 mA/cm2 of 80 keV H0 at the focal plane for pulse lengths up to 15 ms, with low ripple δV / 80 keV 0.05 % at 280 kHz. Diagnostic development and validation tests will be performed on a magnetized plasma test stand with 0.5 T field. The test chamber will utilize a washer-stack arc source to produce a target plasma comparable to edge tokamak plasmas. A bias-plate with programmable power supply will be used to impose Ẽ within the target plasma. Work supported by US DOE Grant DE-FG02-89ER53296.

Analysis and modification of a single-mesh gear fatigue rig for use in diagnostic studies

NASA Technical Reports Server (NTRS)

Zakrajsek, James J.; Townsend, Dennis P.; Oswald, Fred B.; Decker, Harry J.

1992-01-01

A single-mesh gear fatigue rig was analyzed and modified for use in gear mesh diagnostic research. The fatigue rig allowed unwanted vibration to mask the test-gear vibration signal, making it difficult to perform diagnostic studies. Several possible sources and factors contributing to the unwanted components of the vibration signal were investigated. Sensor mounting location was found to have a major effect on the content of the vibration signal. In the presence of unwanted vibration sources, modal amplification made unwanted components strong. A sensor location was found that provided a flatter frequency response. This resulted in a more useful vibration signal. A major network was performed on the fatigue rig to reduce the influence of the most probable sources of the noise in the vibration signal. The slave gears were machined to reduce weight and increase tooth loading. The housing and the shafts were modified to reduce imbalance, looseness, and misalignment in the rotating components. These changes resulted in an improved vibration signal, with the test-gear mesh frequency now the dominant component in the signal. Also, with the unwanted sources eliminated, the sensor mounting location giving the most robust representation of the test-gear meshing energy was found to be at a point close to the test gears in the load zone of the bearings.

21 CFR 660.32 - Collection of source material.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.32 Collection of source material. Blood for Reagent Red Blood Cells from donors of peripheral blood...

21 CFR 660.32 - Collection of source material.

Code of Federal Regulations, 2012 CFR

2012-04-01

...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.32 Collection of source material. Blood for Reagent Red Blood Cells from donors of peripheral blood...

21 CFR 660.32 - Collection of source material.

Code of Federal Regulations, 2011 CFR

2011-04-01

...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.32 Collection of source material. Blood for Reagent Red Blood Cells from donors of peripheral blood...

21 CFR 660.32 - Collection of source material.

Code of Federal Regulations, 2013 CFR

2013-04-01

...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.32 Collection of source material. Blood for Reagent Red Blood Cells from donors of peripheral blood...

A first characterization of the NIO1 particle beam by means of a diagnostic calorimeter

NASA Astrophysics Data System (ADS)

Pimazzoni, A.; Cavenago, M.; Cervaro, V.; Fasolo, D.; Serianni, G.; Tollin, M.; Veltri, P.

2017-08-01

Powerful neutral beam injectors (NBI) are required as heating and current drive systems for tokamaks like ITER. The development of negative ion sources and accelerators (40 A; 1 MeV D- beam) in particular, is a crucial point and many issues still require a better understanding. In this framework, the experiment NIO1 (9 beamlets of 15 mA H- each, 60 kV) operated at Consorzio RFX started operation in 2014[1]. Both its RF negative ion source (up to 2.5 kW) and its beamline are equipped with many diagnostics [2]. For the early tests on the extraction system, oxygen has been used as well as hydrogen due to its higher electronegativity, which allows reaching currents large enough to test the beam diagnostics even without caesium injection. In particular a 1D-CFC (carbon-fibre-carbon composite) tile is used as a calorimeter to determine the beam power deposition by observing the rear surface of the tile with an infra-red camera; the same design is applied as for STRIKE [3], one of the diagnostics of SPIDER (the ITER-like ion source prototype [4]) whose facility is currently under construction at Consorzio RFX. From this diagnostic it is also possible to assess the beam divergence and thus the beam optics. The present contribution describes the characterization of the NIO1 particle beam by means of temperature and current measurements with different source and accelerator parameters.

Castellated tiles as the beam-facing components for the diagnostic calorimeter of the negative ion source SPIDER

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

Peruzzo, S., E-mail: simone.peruzzo@igi.cnr.it; Cervaro, V.; Dalla Palma, M.

2016-02-15

This paper presents the results of numerical simulations and experimental tests carried out to assess the feasibility and suitability of graphite castellated tiles as beam-facing component in the diagnostic calorimeter of the negative ion source SPIDER (Source for Production of Ions of Deuterium Extracted from Radio frequency plasma). The results indicate that this concept could be a reliable, although less performing, alternative for the present design based on carbon fiber composite tiles, as it provides thermal measurements on the required spatial scale.

Castellated tiles as the beam-facing components for the diagnostic calorimeter of the negative ion source SPIDER

NASA Astrophysics Data System (ADS)

Peruzzo, S.; Cervaro, V.; Dalla Palma, M.; Delogu, R.; De Muri, M.; Fasolo, D.; Franchin, L.; Pasqualotto, R.; Pimazzoni, A.; Rizzolo, A.; Tollin, M.; Zampieri, L.; Serianni, G.

2016-02-01

This paper presents the results of numerical simulations and experimental tests carried out to assess the feasibility and suitability of graphite castellated tiles as beam-facing component in the diagnostic calorimeter of the negative ion source SPIDER (Source for Production of Ions of Deuterium Extracted from Radio frequency plasma). The results indicate that this concept could be a reliable, although less performing, alternative for the present design based on carbon fiber composite tiles, as it provides thermal measurements on the required spatial scale.

Advances Afoot in Microbiology.

PubMed

Patel, Robin; Karon, Brad S

2017-07-01

In 2016, the American Academy of Microbiology convened a colloquium to examine point-of-care (POC) microbiology testing and to evaluate its effects on clinical microbiology. Colloquium participants included representatives from clinical microbiology laboratories, industry, and the government, who together made recommendations regarding the implementation, oversight, and evaluation of POC microbiology testing. The colloquium report is timely and well written (V. Dolen et al., Changing Diagnostic Paradigms for Microbiology , 2017, https://www.asm.org/index.php/colloquium-reports/item/6421-changing-diagnostic-paradigms-for-microbiology?utm_source=Commentary&utm_medium=referral&utm_campaign=diagnostics). Emerging POC microbiology tests, especially nucleic acid amplification tests, have the potential to advance medical care. Copyright © 2017 American Society for Microbiology.

Communication gaps in nursing home transfers to the ED: impact on turnaround time, disposition, and diagnostic testing.

PubMed

Nelson, Drew; Washton, Danae; Jeanmonod, Rebecca

2013-04-01

This study aims to determine the source of communication gaps in history of present illness (HPI), medical history, and advanced directives in nursing home (NH) patients transferred to the emergency department (ED). We also attempt to determine if these gaps create differences in patient turnaround time (TAT), disposition decision, or diagnostic testing. A convenience sample of patients transferred from NHs to a level 1 community trauma center was enrolled by the physicians caring for them. The physicians assessed the adequacy and source of the history for each patient. The patient's chart was then retrospectively reviewed to determine disposition, ED TAT, and diagnostic tests ordered. One hundred patients were enrolled. Physicians found that NH paperwork contained adequate HPI 35% of the time. Patients could provide their own HPI 28% of the time. In 32% of patients, adequate HPI could not be obtained from the patient, NH paperwork, or NH personnel. Comparing patients in whom adequate HPI was available (n = 68) to those in whom HPI was not available (n = 32), there was no difference in TAT (146 vs 173 minutes, P = .22), admissions (60% vs 66%, P = .66), or diagnostic testing (P = .89-1.0). Emergency department physicians often do not have adequate HPI in patients transferred from NHs. The absence of adequate information does not affect patient TAT, disposition decision, or ED diagnostic testing. Copyright © 2013 Elsevier Inc. All rights reserved.

Planned Experiments on the Princeton Advanced Test Stand

NASA Astrophysics Data System (ADS)

Stepanov, A.; Gilson, E. P.; Grisham, L.; Kaganovich, I.; Davidson, R. C.

2010-11-01

The Princeton Advanced Test Stand (PATS) device is an experimental facility based on the STS-100 high voltage test stand transferred from LBNL. It consists of a multicusp RF ion source, a pulsed extraction system capable of forming high-perveance 100keV ion beams, and a large six-foot-long vacuum with convenient access for beam diagnostics. This results in a flexible system for studying high perveance ion beams relevant to NDCX-I/II, including experiments on beam neutralization by ferroelectric plasma sources (FEPS) being developed at PPPL. Research on PATS will concern the basic physics of beam-plasma interactions, such as the effects of volume neutralization on beam emittance, as well as optimizing technology of the FEPS. PATS combines the advantage of an ion beam source and a large-volume plasma source in a chamber with ample access for diagnostics, resulting in a robust setup for investigating and improving relevant aspects of neutralized drift. There are also plans for running the ion source with strongly electro-negative gases such as chlorine, making it possible to extract positive or negative ion beams.

Langmuir probes for SPIDER (source for the production of ions of deuterium extracted from radio frequency plasma) experiment: Tests in BATMAN (Bavarian test machine for negative ions)

NASA Astrophysics Data System (ADS)

Brombin, M.; Spolaore, M.; Serianni, G.; Pomaro, N.; Taliercio, C.; Palma, M. Dalla; Pasqualotto, R.; Schiesko, L.

2014-11-01

A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors' holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation. No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.

Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from Radio Frequency plasma) experiment: tests in BATMAN (BAvarian Test Machine for Negative ions).

PubMed

Brombin, M; Spolaore, M; Serianni, G; Pomaro, N; Taliercio, C; Dalla Palma, M; Pasqualotto, R; Schiesko, L

2014-11-01

A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors' holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation. No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.

Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies: The PRISMA-DTA Statement.

PubMed

McInnes, Matthew D F; Moher, David; Thombs, Brett D; McGrath, Trevor A; Bossuyt, Patrick M; Clifford, Tammy; Cohen, Jérémie F; Deeks, Jonathan J; Gatsonis, Constantine; Hooft, Lotty; Hunt, Harriet A; Hyde, Christopher J; Korevaar, Daniël A; Leeflang, Mariska M G; Macaskill, Petra; Reitsma, Johannes B; Rodin, Rachel; Rutjes, Anne W S; Salameh, Jean-Paul; Stevens, Adrienne; Takwoingi, Yemisi; Tonelli, Marcello; Weeks, Laura; Whiting, Penny; Willis, Brian H

2018-01-23

Systematic reviews of diagnostic test accuracy synthesize data from primary diagnostic studies that have evaluated the accuracy of 1 or more index tests against a reference standard, provide estimates of test performance, allow comparisons of the accuracy of different tests, and facilitate the identification of sources of variability in test accuracy. To develop the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) diagnostic test accuracy guideline as a stand-alone extension of the PRISMA statement. Modifications to the PRISMA statement reflect the specific requirements for reporting of systematic reviews and meta-analyses of diagnostic test accuracy studies and the abstracts for these reviews. Established standards from the Enhancing the Quality and Transparency of Health Research (EQUATOR) Network were followed for the development of the guideline. The original PRISMA statement was used as a framework on which to modify and add items. A group of 24 multidisciplinary experts used a systematic review of articles on existing reporting guidelines and methods, a 3-round Delphi process, a consensus meeting, pilot testing, and iterative refinement to develop the PRISMA diagnostic test accuracy guideline. The final version of the PRISMA diagnostic test accuracy guideline checklist was approved by the group. The systematic review (produced 64 items) and the Delphi process (provided feedback on 7 proposed items; 1 item was later split into 2 items) identified 71 potentially relevant items for consideration. The Delphi process reduced these to 60 items that were discussed at the consensus meeting. Following the meeting, pilot testing and iterative feedback were used to generate the 27-item PRISMA diagnostic test accuracy checklist. To reflect specific or optimal contemporary systematic review methods for diagnostic test accuracy, 8 of the 27 original PRISMA items were left unchanged, 17 were modified, 2 were added, and 2 were omitted. The 27-item PRISMA diagnostic test accuracy checklist provides specific guidance for reporting of systematic reviews. The PRISMA diagnostic test accuracy guideline can facilitate the transparent reporting of reviews, and may assist in the evaluation of validity and applicability, enhance replicability of reviews, and make the results from systematic reviews of diagnostic test accuracy studies more useful.

Natural rubber latex skin testing reagents: safety and diagnostic accuracy of nonammoniated latex, ammoniated latex, and latex rubber glove extracts.

PubMed

Hamilton, R G; Adkinson, N F

1996-11-01

Nonammoniated latex, ammoniated latex, and rubber glove extracts are the only sources of natural rubber (Hevea brasiliensis) latex that have potential for use as skin testing reagents in the diagnosis of latex allergy. Their diagnostic sensitivity and specificity as skin test reagents are unknown. We conducted a phase 1/2 clinical study to examine the safety and diagnostic accuracy (sensitivity and specificity) of nonammoniated latex, ammoniated latex, and rubber glove extracts as skin test extracts to identify the most efficacious source material for future skin test reagent development. Twenty-four adults not allergic to latex, 19 adults with hand dermatitis or pruritus, and 59 adults with a latex allergy were identified by clinical history. All provided blood and then received puncture skin tests and intradermal skin tests with nonammoniated latex, ammoniated latex, and rubber glove extracts from Malaysian H. brasiliensis latex by use of sequential titration. A glove provocation test and IgE anti-latex RAST were used to clarify positive history-negative skin test response and negative history-positive skin test response mismatches. All three extracts were biologically safe and sterile. After normalization to 1 mg/ml of total protein, all three extracts produced equivalent diagnostic sensitivity and specificity in puncture skin tests and intradermal skin tests at various extract concentrations. Optimal diagnostic accuracy was safely achieved at 100 micrograms/ml for intradermal skin tests (e.g., nonammoniated latex: puncture skin test sensitivity 96%, specificity 100%; intradermal skin test sensitivity 93%, specificity 96%). The presence of IgE antibody in skin was highly correlated with IgE anti-latex in serum (nonammoniated latex: r = 0.98, p < 0.001; ammoniated latex: r = 0.94, p < 0.001; rubber glove extract: r = 0.96, p < 0.001). All five available subjects with a positive history, negative skin test response, and absence of IgE antibody in serum had a negative glove provocation test response, indicating no clinical evidence of latex allergy. No systemic or large local allergic reactions were observed with puncture skin tests or intradermal skin tests. Equivalent diagnostic sensitivity and specificity were observed with the nonammoniated latex, ammoniated latex, and rubber glove extract skin test reagents after normalization for total protein; nonammoniated latex may be considered the reagent of choice on the basis of practical quality control and reproducibility considerations.

Radiation safety.

PubMed

Skinner, Sarah

2013-06-01

Diagnostic radiology procedures, such as computed tomography (CT) and X-ray, are an increasing source of ionising radiation exposure to our community. Exposure to ionising radiation is associated with increased risk of malignancy, proportional to the level of exposure. Every diagnostic test using ionising radiation needs to be justified by clinical need. General practitioners need a working knowledge of radiation safety so they can adequately inform their patients of the risks and benefits of diagnostic imaging procedures.

40 CFR 60.53b - Standards for municipal waste combustor operating practices.

Code of Federal Regulations, 2011 CFR

2011-07-01

... for the purpose of evaluating system performance, testing new technology or control technologies... evaluating system performance, testing new technology or control technologies, diagnostic testing, or related... (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of...

A negative ion source test facility

NASA Astrophysics Data System (ADS)

Melanson, S.; Dehnel, M.; Potkins, D.; Theroux, J.; Hollinger, C.; Martin, J.; Philpott, C.; Stewart, T.; Jackle, P.; Williams, P.; Brown, S.; Jones, T.; Coad, B.; Withington, S.

2016-02-01

Progress is being made in the development of an Ion Source Test Facility (ISTF) by D-Pace Inc. in collaboration with Buckley Systems Ltd. in Auckland, NZ. The first phase of the ISTF is to be commissioned in October 2015 with the second phase being commissioned in March 2016. The facility will primarily be used for the development and the commercialization of ion sources. It will also be used to characterize and further develop various D-Pace Inc. beam diagnostic devices.

Fan Noise Source Diagnostic Test Computation of Rotor Wake Turbulence Noise

NASA Technical Reports Server (NTRS)

Nallasamy, M.; Envia, E.; Thorp, S. A.; Shabbir, A.

2002-01-01

An important source mechanism of fan broadband noise is the interaction of rotor wake turbulence with the fan outlet guide vanes. A broadband noise model that utilizes computed rotor flow turbulence from a RANS code is used to predict fan broadband noise spectra. The noise model is employed to examine the broadband noise characteristics of the 22-inch Source Diagnostic Test fan rig for which broadband noise data were obtained in wind tunnel tests at the NASA Glenn Research Center. A 9-case matrix of three outlet guide vane configurations at three representative fan tip speeds are considered. For all cases inlet and exhaust acoustic power spectra are computed and compared with the measured spectra where possible. In general, the acoustic power levels and shape of the predicted spectra are in good agreement with the measured data. The predicted spectra show the experimentally observed trends with fan tip speed, vane count, and vane sweep. The results also demonstrate the validity of using CFD-based turbulence information for fan broadband noise calculations.

Langmuir probes for SPIDER (source for the production of ions of deuterium extracted from radio frequency plasma) experiment: Tests in BATMAN (Bavarian test machine for negative ions)

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

Brombin, M., E-mail: matteo.brombin@igi.cnr.it; Spolaore, M.; Serianni, G.

2014-11-15

A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors’ holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation.more » No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.« less

Iridology: A systematic review.

PubMed

Ernst, E

1999-02-01

Iridologists claim to be able to diagnose medical conditions through abnormalities of pigmentation in the iris. This technique is popular in many countries. Therefore it is relevant to ask whether it is valid. To systematically review all interpretable tests of the validity of iridology as a diagnostic tool. DATA SOURCE AND EXTRACTION: Three independent literature searches were performed to identify all blinded tests. Data were extracted in a predefined, standardized fashion. Four case control studies were found. The majority of these investigations suggests that iridology is not a valid diagnostic method. The validity of iridology as a diagnostic tool is not supported by scientific evaluations. Patients and therapists should be discouraged from using this method.

Simple Sample Processing Enhances Malaria Rapid Diagnostic Test Performance

PubMed Central

Davis, K. M.; Gibson, L. E.; Haselton, F. R.; Wright, D. W.

2016-01-01

Lateral flow immunochromatographic rapid diagnostic tests (RDTs) are the primary form of medical diagnostic used for malaria in underdeveloped nations. Unfortunately, many of these tests do not detect asymptomatic malaria carriers. In order for eradication of the disease to be achieved, this problem must be solved. In this study, we demonstrate enhancement in the performance of six RDT brands when a simple sample-processing step is added to the front of the diagnostic process. Greater than a 4-fold RDT signal enhancement was observed as a result of the sample processing step. This lowered the limit of detection for RDT brands to submicroscopic parasitemias. For the best performing RDTs the limits of detection were found to be as low as 3 parasites/μL. Finally, through individual donor samples, the correlations between donor source, WHO panel detection scores and RDT signal intensities were explored. PMID:24787948

Simple sample processing enhances malaria rapid diagnostic test performance.

PubMed

Davis, K M; Gibson, L E; Haselton, F R; Wright, D W

2014-06-21

Lateral flow immunochromatographic rapid diagnostic tests (RDTs) are the primary form of medical diagnostic used for malaria in underdeveloped nations. Unfortunately, many of these tests do not detect asymptomatic malaria carriers. In order for eradication of the disease to be achieved, this problem must be solved. In this study, we demonstrate enhancement in the performance of six RDT brands when a simple sample-processing step is added to the front of the diagnostic process. Greater than a 4-fold RDT signal enhancement was observed as a result of the sample processing step. This lowered the limit of detection for RDT brands to submicroscopic parasitemias. For the best performing RDTs the limits of detection were found to be as low as 3 parasites per μL. Finally, through individual donor samples, the correlations between donor source, WHO panel detection scores and RDT signal intensities were explored.

Diagnostic techniques for measurement of aerodynamic noise in free field and reverberant environment of wind tunnels

NASA Technical Reports Server (NTRS)

El-Sum, H. M. A.; Mawardi, O. K.

1973-01-01

Techniques for studying aerodynamic noise generating mechanisms without disturbing the flow in a free field, and in the reverberation environment of the ARC wind tunnel were investigated along with the design and testing of an acoustic antenna with an electronic steering control. The acoustic characteristics of turbojet as a noise source, detection of direct sound from a source in a reverberant background, optical diagnostic methods, and the design characteristics of a high directivity acoustic antenna. Recommendations for further studies are included.

Introduction to basic solar cell measurements

NASA Technical Reports Server (NTRS)

Brandhorst, H. W., Jr.

1976-01-01

The basic approaches to solar cell performance and diagnostic measurements are described. The light sources, equipment for I-V curve measurement, and the test conditions and procedures for performance measurement are detailed. Solar cell diagnostic tools discussed include analysis of I-V curves, series resistance and reverse saturation current determination, spectral response/quantum yield measurement, and diffusion length/lifetime determination.

Loopback Tester: a synchronous communications circuit diagnostic device

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

Maestas, J.H.

1986-07-01

The Loopback Tester is an Intel SBC 86/12A Single Board Computer and an Intel SBC 534 Communications Expansion Board configured and programmed to perform various basic or less. These tests include: (1) Data Communications Equipment (DCE) transmit timing detection (2) data rate measurement (3) instantaneous loopback indication and (4) bit error rate testing. It requires no initial setup after plug in, and can be used to locate the source of communications loss in a circuit. It can also be used to determine when crypto variable mismatch problems are the source of communications loss. This report discusses the functionality of themore » Loopback Tester as a diagnostic device. It also discusses the hardware and software which implements this simple yet reliable device.« less

Diagnostic accuracy of physical examination tests of the ankle/foot complex: a systematic review.

PubMed

Schwieterman, Braun; Haas, Deniele; Columber, Kirby; Knupp, Darren; Cook, Chad

2013-08-01

Orthopedic special tests of the ankle/foot complex are routinely used during the physical examination process in order to help diagnose ankle/lower leg pathologies. The purpose of this systematic review was to investigate the diagnostic accuracy of ankle/lower leg special tests. A search of the current literature was conducted using PubMed, CINAHL, SPORTDiscus, ProQuest Nursing and Allied Health Sources, Scopus, and Cochrane Library. Studies were eligible if they included the following: 1) a diagnostic clinical test of musculoskeletal pathology in the ankle/foot complex, 2) description of the clinical test or tests, 3) a report of the diagnostic accuracy of the clinical test (e.g. sensitivity and specificity), and 4) an acceptable reference standard for comparison. The quality of included studies was determined by two independent reviewers using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Nine diagnostic accuracy studies met the inclusion criteria for this systematic review; analyzing a total of 16 special tests of the ankle/foot complex. After assessment using the QUADAS-2, only one study had low risk of bias and low concerns regarding applicability. Most ankle/lower leg orthopedic special tests are confirmatory in nature and are best utilized at the end of the physical examination. Most of the studies included in this systematic review demonstrate notable biases, which suggest that results and recommendations in this review should be taken as a guide rather than an outright standard. There is need for future research with more stringent study design criteria so that more accurate diagnostic power of ankle/lower leg special tests can be determined. 3a.

DIAGNOSTIC ACCURACY OF PHYSICAL EXAMINATION TESTS OF THE ANKLE/FOOT COMPLEX: A SYSTEMATIC REVIEW

PubMed Central

Schwieterman, Braun; Haas, Deniele; Columber, Kirby; Knupp, Darren

2013-01-01

Background: Orthopedic special tests of the ankle/foot complex are routinely used during the physical examination process in order to help diagnose ankle/lower leg pathologies. Purpose: The purpose of this systematic review was to investigate the diagnostic accuracy of ankle/lower leg special tests. Methods: A search of the current literature was conducted using PubMed, CINAHL, SPORTDiscus, ProQuest Nursing and Allied Health Sources, Scopus, and Cochrane Library. Studies were eligible if they included the following: 1) a diagnostic clinical test of musculoskeletal pathology in the ankle/foot complex, 2) description of the clinical test or tests, 3) a report of the diagnostic accuracy of the clinical test (e.g. sensitivity and specificity), and 4) an acceptable reference standard for comparison. The quality of included studies was determined by two independent reviewers using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Results: Nine diagnostic accuracy studies met the inclusion criteria for this systematic review; analyzing a total of 16 special tests of the ankle/foot complex. After assessment using the QUADAS-2, only one study had low risk of bias and low concerns regarding applicability. Conclusion: Most ankle/lower leg orthopedic special tests are confirmatory in nature and are best utilized at the end of the physical examination. Most of the studies included in this systematic review demonstrate notable biases, which suggest that results and recommendations in this review should be taken as a guide rather than an outright standard. There is need for future research with more stringent study design criteria so that more accurate diagnostic power of ankle/lower leg special tests can be determined. Level of Evidence: 3a PMID:24175128

Get the Diagnosis: an evidence-based medicine collaborative Wiki for diagnostic test accuracy.

PubMed

Hammer, Mark M; Kohlberg, Gavriel D

2017-04-01

Despite widespread calls for its use, there are challenges to the implementation of evidence-based medicine (EBM) in clinical practice. In response to the challenges of finding timely, pertinent information on diagnostic test accuracy, we developed an online, crowd-sourced Wiki on diagnostic test accuracy called Get the Diagnosis (GTD, http://www.getthediagnosis.org). Since its launch in November 2008 till October 2015, GTD has accumulated information on 300 diagnoses, with 1617 total diagnostic entries. There are a total of 1097 unique diagnostic tests with a mean of 5.4 tests (range 0-38) per diagnosis. 73% of entries (1182 of 1617) have an associated sensitivity and specificity and 89% of entries (1432 of 1617) have associated peer-reviewed literature citations. Altogether, GTD contains 474 unique literature citations. For a sample of three diagnoses, the search precision (percentage of relevant results in the first 30 entries) in GTD was 100% as compared with a range of 13.3%-63.3% for PubMed and between 6.7% and 76.7% for Google Scholar. GTD offers a fast, precise and efficient way to look up diagnostic test accuracy. On three selected examples, GTD had a greater precision rate compared with PubMed and Google Scholar in identifying diagnostic test information. GTD is a free resource that complements other currently available resources. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Diagnostic accuracy research in glaucoma is still incompletely reported: An application of Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015.

PubMed

Michelessi, Manuele; Lucenteforte, Ersilia; Miele, Alba; Oddone, Francesco; Crescioli, Giada; Fameli, Valeria; Korevaar, Daniël A; Virgili, Gianni

2017-01-01

Research has shown a modest adherence of diagnostic test accuracy (DTA) studies in glaucoma to the Standards for Reporting of Diagnostic Accuracy Studies (STARD). We have applied the updated 30-item STARD 2015 checklist to a set of studies included in a Cochrane DTA systematic review of imaging tools for diagnosing manifest glaucoma. Three pairs of reviewers, including one senior reviewer who assessed all studies, independently checked the adherence of each study to STARD 2015. Adherence was analyzed on an individual-item basis. Logistic regression was used to evaluate the effect of publication year and impact factor on adherence. We included 106 DTA studies, published between 2003-2014 in journals with a median impact factor of 2.6. Overall adherence was 54.1% for 3,286 individual rating across 31 items, with a mean of 16.8 (SD: 3.1; range 8-23) items per study. Large variability in adherence to reporting standards was detected across individual STARD 2015 items, ranging from 0 to 100%. Nine items (1: identification as diagnostic accuracy study in title/abstract; 6: eligibility criteria; 10: index test (a) and reference standard (b) definition; 12: cut-off definitions for index test (a) and reference standard (b); 14: estimation of diagnostic accuracy measures; 21a: severity spectrum of diseased; 23: cross-tabulation of the index and reference standard results) were adequately reported in more than 90% of the studies. Conversely, 10 items (3: scientific and clinical background of the index test; 11: rationale for the reference standard; 13b: blinding of index test results; 17: analyses of variability; 18; sample size calculation; 19: study flow diagram; 20: baseline characteristics of participants; 28: registration number and registry; 29: availability of study protocol; 30: sources of funding) were adequately reported in less than 30% of the studies. Only four items showed a statistically significant improvement over time: missing data (16), baseline characteristics of participants (20), estimates of diagnostic accuracy (24) and sources of funding (30). Adherence to STARD 2015 among DTA studies in glaucoma research is incomplete, and only modestly increasing over time.

Fan Noise Source Diagnostic Test: Rotor Alone Aerodynamic Performance Results

NASA Technical Reports Server (NTRS)

Hughes, Christopher E.; Jeracki, Robert J.; Woodward, Richard P.; Miller, Christopher J.

2005-01-01

The aerodynamic performance of an isolated fan or rotor alone model was measured in the NASA Glenn Research Center 9- by 15- Foot Low Speed Wind Tunnel as part of the Fan Broadband Source Diagnostic Test conducted at NASA Glenn. The Source Diagnostic Test was conducted to identify the noise sources within a wind tunnel scale model of a turbofan engine and quantify their contribution to the overall system noise level. The fan was part of a 1/5th scale model representation of the bypass stage of a current technology turbofan engine. For the rotor alone testing, the fan and nacelle, including the inlet, external cowl, and fixed area fan exit nozzle, were modeled in the test hardware; the internal outlet guide vanes located behind the fan were removed. Without the outlet guide vanes, the velocity at the nozzle exit changes significantly, thereby affecting the fan performance. As part of the investigation, variations in the fan nozzle area were tested in order to match as closely as possible the rotor alone performance with the fan performance obtained with the outlet guide vanes installed. The fan operating performance was determined using fixed pressure/temperature combination rakes and the corrected weight flow. The performance results indicate that a suitable nozzle exit was achieved to be able to closely match the rotor alone and fan/outlet guide vane configuration performance on the sea level operating line. A small shift in the slope of the sea level operating line was measured, which resulted in a slightly higher rotor alone fan pressure ratio at take-off conditions, matched fan performance at cutback conditions, and a slightly lower rotor alone fan pressure ratio at approach conditions. However, the small differences in fan performance at all fan conditions were considered too small to affect the fan acoustic performance.

Correlation of clinical examination characteristics with three sources of chronic low back pain.

PubMed

Young, Sharon; Aprill, Charles; Laslett, Mark

2003-01-01

Research has demonstrated some progress in using a clinical examination to predict discogenic or sacroiliac (SI) joint sources of pain. No clear predictors of symptomatic lumbar zygapophysial joints have yet been demonstrated. To identify significant components of a clinical examination that are associated with symptomatic lumbar discs, zygapophysial joints and SI joints. A prospective, criterion-related concurrent validity study performed at a private radiology practice specializing in spinal diagnostics. The sample consisted of 81 patients with chronic lumbopelvic pain referred for diagnostic injections. Contingency tables were constructed for nine features of the clinical evaluation compared with the results of diagnostic injections. Statistical analysis included chi-squared test for independence, phi and odds ratios with confidence intervals. Patients received blinded clinical examinations by physical therapists, and diagnostic injections were used as the criterion standard. Significant relationships were found between discogenic pain and centralization of pain during repeated movement testing, and pain when rising from sitting. Lumbar zygapophysial joint pain was associated with absence of pain when rising from sitting. Sacroiliac joint pain was related to three or more positive pain provocation tests, pain when rising from sitting, unilateral pain and absence of lumbar pain. Significant correlations exist between clinical examination findings and symptomatic lumbar discs, zygapophysial and SI joints. The strongest relationships were seen between SI joint pain and three or more positive pain provocation tests, centralization of pain for symptomatic discs and absence of pain when rising from sitting for symptomatic lumbar zygapophysial joints.

The front end test stand high performance H- ion source at Rutherford Appleton Laboratory.

PubMed

Faircloth, D C; Lawrie, S; Letchford, A P; Gabor, C; Wise, P; Whitehead, M; Wood, T; Westall, M; Findlay, D; Perkins, M; Savage, P J; Lee, D A; Pozimski, J K

2010-02-01

The aim of the front end test stand (FETS) project is to demonstrate that chopped low energy beams of high quality can be produced. FETS consists of a 60 mA Penning Surface Plasma Ion Source, a three solenoid low energy beam transport, a 3 MeV radio frequency quadrupole, a chopper, and a comprehensive suite of diagnostics. This paper details the design and initial performance of the ion source and the laser profile measurement system. Beam current, profile, and emittance measurements are shown for different operating conditions.

Single-shot, high-resolution, fiber-based phase-diversity photodetection of optical pulses

NASA Astrophysics Data System (ADS)

Dorrer, C.; Waxer, L. J.; Kalb, A.; Hill, E. M.; Bromage, J.

2016-03-01

Temporally characterizing optical pulses is an important task when building, optimizing, and using optical sources. Direct photodetection with high-bandwidth photodiodes and real-time oscilloscopes is only adequate for optical pulses longer than ~10 ps; diagnostics based on indirect strategies are required to characterize femtosecond and sub-10-ps coherent sources. Most of these diagnostics are based on nonlinear optics and can be difficult to implement for the single-shot characterization of nonrepetitive events. A temporal diagnostic based on phase diversity is demonstrated in the context of picosecond high-energy laser systems, where single-shot pulse measurements are required for system safety and interpretation of experimental results. A plurality of ancillary optical pulses obtained by adding known amounts of chromatic dispersion to the pulse under test are directly measured by photodetection and processed to reconstruct the input pulse shape. This high-sensitivity (~50-pJ) diagnostic is based on a pulse replicator composed of fiber splitters and delay fibers, making it possible to operate with fiber sources and free-space sources after fiber coupling. Experimental data obtained with a high-bandwidth real-time oscilloscope demonstrate accurate characterization of pulses from a high-energy chirped-pulse amplification system, even for pulses shorter than the photodetection impulse response.

Modeling and design of a beam emission spectroscopy diagnostic for the negative ion source NIO1

NASA Astrophysics Data System (ADS)

Barbisan, M.; Zaniol, B.; Cavenago, M.; Pasqualotto, R.

2014-02-01

Consorzio RFX and INFN-LNL are building a flexible small ion source (Negative Ion Optimization 1, NIO1) capable of producing about 130 mA of H- ions accelerated at 60 KeV. Aim of the experiment is to test and develop the instrumentation for SPIDER and MITICA, the prototypes, respectively, of the negative ion sources and of the whole neutral beam injectors which will operate in the ITER experiment. As SPIDER and MITICA, NIO1 will be monitored with beam emission spectroscopy (BES), a non-invasive diagnostic based on the analysis of the spectrum of the Hα emission produced by the interaction of the energetic ions with the background gas. Aim of BES is to monitor direction, divergence, and uniformity of the ion beam. The precision of these measurements depends on a number of factors related to the physics of production and acceleration of the negative ions, to the geometry of the beam, and to the collection optics. These elements were considered in a set of codes developed to identify the configuration of the diagnostic which minimizes the measurement errors. The model was already used to design the BES diagnostic for SPIDER and MITICA. The paper presents the model and describes its application to design the BES diagnostic in NIO1.

Characterizing the Performance of the Princeton Advanced Test Stand Ion Source

NASA Astrophysics Data System (ADS)

Stepanov, A.; Gilson, E. P.; Grisham, L.; Kaganovich, I.; Davidson, R. C.

2012-10-01

The Princeton Advanced Test Stand (PATS) is a compact experimental facility for studying the physics of intense beam-plasma interactions relevant to the Neutralized Drift Compression Experiment - II (NDCX-II). The PATS facility consists of a multicusp RF ion source mounted on a 2 m-long vacuum chamber with numerous ports for diagnostic access. Ar+ beams are extracted from the source plasma with three-electrode (accel-decel) extraction optics. The RF power and extraction voltage (30 - 100 kV) are pulsed to produce 100 μsec duration beams at 0.5 Hz with excellent shot-to-shot repeatability. Diagnostics include Faraday cups, a double-slit emittance scanner, and scintillator imaging. This work reports measurements of beam parameters for a range of beam energies (30 - 50 keV) and currents to characterize the behavior of the ion source and extraction optics. Emittance scanner data is used to calculate the beam trace-space distribution and corresponding transverse emittance. If the plasma density is changing during a beam pulse, time-resolved emittance scanner data has been taken to study the corresponding evolution of the beam trace-space distribution.

Conjugation of fiber-coupled wide-band light sources and acousto-optical spectral elements

NASA Astrophysics Data System (ADS)

Machikhin, Alexander; Batshev, Vladislav; Polschikova, Olga; Khokhlov, Demid; Pozhar, Vitold; Gorevoy, Alexey

2017-12-01

Endoscopic instrumentation is widely used for diagnostics and surgery. The imaging systems, which provide the hyperspectral information of the tissues accessible by endoscopes, are particularly interesting and promising for in vivo photoluminescence diagnostics and therapy of tumour and inflammatory diseases. To add the spectral imaging feature to standard video endoscopes, we propose to implement acousto-optical (AO) filtration of wide-band illumination of incandescent-lamp-based light sources. To collect maximum light and direct it to the fiber-optic light guide inside the endoscopic probe, we have developed and tested the optical system for coupling the light source, the acousto-optical tunable filter (AOTF) and the light guide. The system is compact and compatible with the standard endoscopic components.

A Meta-Analysis of Typhoid Diagnostic Accuracy Studies: A Recommendation to Adopt a Standardized Composite Reference

PubMed Central

Storey, Helen L.; Huang, Ying; Crudder, Chris; Golden, Allison; de los Santos, Tala; Hawkins, Kenneth

2015-01-01

Novel typhoid diagnostics currently under development have the potential to improve clinical care, surveillance, and the disease burden estimates that support vaccine introduction. Blood culture is most often used as the reference method to evaluate the accuracy of new typhoid tests; however, it is recognized to be an imperfect gold standard. If no single gold standard test exists, use of a composite reference standard (CRS) can improve estimation of diagnostic accuracy. Numerous studies have used a CRS to evaluate new typhoid diagnostics; however, there is no consensus on an appropriate CRS. In order to evaluate existing tests for use as a reference test or inclusion in a CRS, we performed a systematic review of the typhoid literature to include all index/reference test combinations observed. We described the landscape of comparisons performed, showed results of a meta-analysis on the accuracy of the more common combinations, and evaluated sources of variability based on study quality. This wide-ranging meta-analysis suggests that no single test has sufficiently good performance but some existing diagnostics may be useful as part of a CRS. Additionally, based on findings from the meta-analysis and a constructed numerical example demonstrating the use of CRS, we proposed necessary criteria and potential components of a typhoid CRS to guide future recommendations. Agreement and adoption by all investigators of a standardized CRS is requisite, and would improve comparison of new diagnostics across independent studies, leading to the identification of a better reference test and improved confidence in prevalence estimates. PMID:26566275

Atomic Resonance Radiation Energetics Investigation as a Diagnostic Method for Non-Equilibrium Hypervelocity Flows

NASA Technical Reports Server (NTRS)

Meyer, Scott A.; Bershader, Daniel; Sharma, Surendra P.; Deiwert, George S.

1996-01-01

Absorption measurements with a tunable vacuum ultraviolet light source have been proposed as a concentration diagnostic for atomic oxygen, and the viability of this technique is assessed in light of recent measurements. The instrumentation, as well as initial calibration measurements, have been reported previously. We report here additional calibration measurements performed to study the resonance broadening line shape for atomic oxygen. The application of this diagnostic is evaluated by considering the range of suitable test conditions and requirements, and by identifying issues that remain to be addressed.

Portable Health Algorithms Test System

NASA Technical Reports Server (NTRS)

Melcher, Kevin J.; Wong, Edmond; Fulton, Christopher E.; Sowers, Thomas S.; Maul, William A.

2010-01-01

A document discusses the Portable Health Algorithms Test (PHALT) System, which has been designed as a means for evolving the maturity and credibility of algorithms developed to assess the health of aerospace systems. Comprising an integrated hardware-software environment, the PHALT system allows systems health management algorithms to be developed in a graphical programming environment, to be tested and refined using system simulation or test data playback, and to be evaluated in a real-time hardware-in-the-loop mode with a live test article. The integrated hardware and software development environment provides a seamless transition from algorithm development to real-time implementation. The portability of the hardware makes it quick and easy to transport between test facilities. This hard ware/software architecture is flexible enough to support a variety of diagnostic applications and test hardware, and the GUI-based rapid prototyping capability is sufficient to support development execution, and testing of custom diagnostic algorithms. The PHALT operating system supports execution of diagnostic algorithms under real-time constraints. PHALT can perform real-time capture and playback of test rig data with the ability to augment/ modify the data stream (e.g. inject simulated faults). It performs algorithm testing using a variety of data input sources, including real-time data acquisition, test data playback, and system simulations, and also provides system feedback to evaluate closed-loop diagnostic response and mitigation control.

Clostridium difficile

PubMed Central

Curry, Scott R.

2017-01-01

SYNOPSIS Clostridium difficile infections (CDI) have emerged as one of the principal threats to the health of hospitalized and immunocompromised patients. Nucleic acid testing for C. difficile toxin genes has eclipsed traditional clinical diagnostics for CDI in sensitivity and is now widespread in clinical use, but preliminary evidence suggests that this may have come at a cost of substantially reduced positive predictive value. The importance of C. difficile colonization is increasingly recognized not only as a source for false positive clinical testing but also as a source of new infections within hospitals and other healthcare environments. In the last five years, several new treatment strategies that capitalize on the increasing understanding of the altered microbiome and host defenses in CDI patients have completed clinical trials, including fecal microbiota transplantation (FMT). This article highlights the changing epidemiology, laboratory diagnostics, pathogenesis, and treatment of CDI. PMID:20513554

Development of an Information Fusion System for Engine Diagnostics and Health Management

NASA Technical Reports Server (NTRS)

Volponi, Allan J.; Brotherton, Tom; Luppold, Robert; Simon, Donald L.

2004-01-01

Aircraft gas-turbine engine data are available from a variety of sources including on-board sensor measurements, maintenance histories, and component models. An ultimate goal of Propulsion Health Management (PHM) is to maximize the amount of meaningful information that can be extracted from disparate data sources to obtain comprehensive diagnostic and prognostic knowledge regarding the health of the engine. Data Fusion is the integration of data or information from multiple sources, to achieve improved accuracy and more specific inferences than can be obtained from the use of a single sensor alone. The basic tenet underlying the data/information fusion concept is to leverage all available information to enhance diagnostic visibility, increase diagnostic reliability and reduce the number of diagnostic false alarms. This paper describes a basic PHM Data Fusion architecture being developed in alignment with the NASA C17 Propulsion Health Management (PHM) Flight Test program. The challenge of how to maximize the meaningful information extracted from disparate data sources to obtain enhanced diagnostic and prognostic information regarding the health and condition of the engine is the primary goal of this endeavor. To address this challenge, NASA Glenn Research Center (GRC), NASA Dryden Flight Research Center (DFRC) and Pratt & Whitney (P&W) have formed a team with several small innovative technology companies to plan and conduct a research project in the area of data fusion as applied to PHM. Methodologies being developed and evaluated have been drawn from a wide range of areas including artificial intelligence, pattern recognition, statistical estimation, and fuzzy logic. This paper will provide a broad overview of this work, discuss some of the methodologies employed and give some illustrative examples.

Nosocomial Candidiasis: Antifungal Stewardship and the Importance of Rapid Diagnosis.

PubMed

Pfaller, Michael A; Castanheira, Mariana

2016-01-01

Candidemia and other forms of candidiasis are associated with considerable excess mortality and costs. Despite the addition of several new antifungal agents with improved spectrum and potency, the frequency of Candida infection and associated mortality have not decreased in the past two decades. The lack of rapid and sensitive diagnostic tests has led to considerable overuse of antifungal agents resulting in increased costs, selection pressure for resistance, unnecessary drug toxicity, and adverse drug interactions. Both the lack of timely diagnostic tests and emergence of antifungal resistance pose considerable problems for antifungal stewardship. Whereas antifungal stewardship with a focus on nosocomial candidiasis should be able to improve the administration of antifungal therapy in terms of drug selection, proper dose and duration, source control and de-escalation therapy, an important parameter, timeliness of antifungal therapy, remains a victim of slow and insensitive diagnostic tests. Fortunately, new proteomic and molecular diagnostic tools are improving the time to species identification and detection. In this review we will describe the potential impact that rapid diagnostic testing and antifungal stewardship can have on the management of nosocomial candidiasis. © The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Progress on development of SPIDER diagnostics

NASA Astrophysics Data System (ADS)

Pasqualotto, R.; Agostini, M.; Barbisan, M.; Bernardi, M.; Brombin, M.; Cavazzana, R.; Croci, G.; Palma, M. Dalla; Delogu, R. S.; Gorini, G.; Lotto, L.; Muraro, A.; Peruzzo, S.; Pimazzoni, A.; Pomaro, N.; Rizzolo, A.; Serianni, G.; Spolaore, M.; Tardocchi, M.; Zaniol, B.; Zaupa, M.

2017-08-01

SPIDER experiment, the full size prototype of the beam source for the ITER heating neutral beam injector, has to demonstrate extraction and acceleration to 100 kV of a large negative ion hydrogen or deuterium beam with co-extracted electron fraction e-/D- <1 and beam uniformity within 10%, for up to one hour beam pulses. Main RF source plasma and beam parameters are measured with different complementary techniques to exploit the combination of their specific features. While SPIDER plant systems are being installed, the different diagnostic systems are in the procurement phase. Their final design is described here with a focus on some key solutions and most original and cost effective implementations. Thermocouples used to measure the power load distribution in the source and over the beam dump front surface will be efficiently fixed with proven technique and acquired through commercial and custom electronics. Spectroscopy needs to use well collimated lines of sight and will employ novel design spectrometers with higher efficiency and resolution and filtered detectors with custom built amplifiers. The electrostatic probes will be operated through electronics specifically developed to cope with the challenging environment of the RF source. The instrumented calorimeter STRIKE will use new CFC tiles, still under development. Two linear cameras, one built in house, have been tested as suitable for optical beam tomography. Some diagnostic components are off the shelf, others are custom developed: some of these are being prototyped or are under test before final production and installation, which will be completed before start of SPIDER operation.

Use of a pLDH-based dipstick in the diagnostic and therapeutic follow-up of malaria patients in Mali

PubMed Central

2011-01-01

Background Malaria is a major public health problem in Mali and diagnosis is typically based on microscopy. Microscopy requires a well trained technician, a reliable power source, a functioning microscope and adequate supplies. The scarcity of resources of community health centres (CHC) does not allow for such a significant investment in only one aspect of malaria control. In this context, Rapid Diagnostic Tests (RDTs) may improve case management particularly in remote areas. Methods This multicentre study included 725 patients simultaneously screened with OptiMal-IT test and thick smears for malaria parasite detection. While evaluating the therapeutic efficacy of choroquine in 2 study sites, we compared the diagnostic values of thick smear microscopy to OptiMal-IT test applying the WHO 14 days follow-up scheme using samples collected from 344 patients. Results The sensitivity and the specificity of OptiMal-IT compared to thick smear was 97.2% and 95.4%, whereas the positive and negative predictive values were 96.7 and 96.1%, respectively. The percent agreement between the two diagnostic tests was 0.93. The two tests were comparable in detecting malaria at day 0, day 3 and day 14. The only difference was observed at day 7 due to high gametocytemia. Subjectively, health care providers found OptiMal-IT easier to use and store under field conditions. Conclusion OptiMal-IT test revealed similar results when compared to microscopy which is considered the gold standard for malaria diagnostics. The test was found to have a short processing time and was easier to use. These advantages may improve malaria case management by providing a diagnostic and drug efficacy follow-up tool to peripheral health centres with limited resources. PMID:22114867

Does clinical pretest probability influence image quality and diagnostic accuracy in dual-source coronary CT angiography?

PubMed

Thomas, Christoph; Brodoefel, Harald; Tsiflikas, Ilias; Bruckner, Friederike; Reimann, Anja; Ketelsen, Dominik; Drosch, Tanja; Claussen, Claus D; Kopp, Andreas; Heuschmid, Martin; Burgstahler, Christof

2010-02-01

To prospectively evaluate the influence of the clinical pretest probability assessed by the Morise score onto image quality and diagnostic accuracy in coronary dual-source computed tomography angiography (DSCTA). In 61 patients, DSCTA and invasive coronary angiography were performed. Subjective image quality and accuracy for stenosis detection (>50%) of DSCTA with invasive coronary angiography as gold standard were evaluated. The influence of pretest probability onto image quality and accuracy was assessed by logistic regression and chi-square testing. Correlations of image quality and accuracy with the Morise score were determined using linear regression. Thirty-eight patients were categorized into the high, 21 into the intermediate, and 2 into the low probability group. Accuracies for the detection of significant stenoses were 0.94, 0.97, and 1.00, respectively. Logistic regressions and chi-square tests showed statistically significant correlations between Morise score and image quality (P < .0001 and P < .001) and accuracy (P = .0049 and P = .027). Linear regression revealed a cutoff Morise score for a good image quality of 16 and a cutoff for a barely diagnostic image quality beyond the upper Morise scale. Pretest probability is a weak predictor of image quality and diagnostic accuracy in coronary DSCTA. A sufficient image quality for diagnostic images can be reached with all pretest probabilities. Therefore, coronary DSCTA might be suitable also for patients with a high pretest probability. Copyright 2010 AUR. Published by Elsevier Inc. All rights reserved.

Greater Real-Life Diagnostic Efficacy of Allergen Molecule-Based Diagnosis for Prescription of Immunotherapy in an Area with Multiple Pollen Exposure

PubMed Central

Saltabayeva, Ulbosin; Garib, Victoria; Morenko, Marina; Rosenson, Rafail; Ispayeva, Zhanat; Gatauova, Madina; Zulus, Loreta; Karaulov, Alexander; Gastager, Felix; Valenta, Rudolf

2017-01-01

Background Allergen molecule-based diagnosis has been suggested to facilitate the identification of disease-causing allergen sources and the prescription of allergen-specific immunotherapy (AIT). The aim of the current study was to compare allergen molecule-based IgE serology with allergen extract-based skin testing for the identification of the disease-causing allergen sources. The study was conducted in an area where patients are exposed to pollen from multiple sources (trees, grasses, and weeds) at the same time to compare the diagnostic efficiency of the 2 forms of diagnosis. Methods Patients from Astana, Kazakhstan, who suffered from pollen-induced allergy (n = 95) were subjected to skin prick testing (SPT) with a local panel of tree pollen, grass pollen, and weed pollen allergen extracts and IgE antibodies specific for marker allergen molecules (nArt v 1, nArt v 3, rAmb a 1, rPhl p 1, rPhl p 5, rBet v 1) were measured by ImmunoCAP. Direct and indirect costs for diagnosis based on SPT and marker allergen-based IgE serology as well as direct costs for immunotherapy depending on SPT and serological test results were calculated. Results The costs for SPT-based diagnosis per patient were lower than the costs for allergen molecule-based IgE serology. However, allergen molecule-based serology was more precise in detecting the disease-causing allergen sources. A lower number of immunotherapy treatments (n = 119) was needed according to molecular diagnosis as compared to extract-based diagnosis (n = 275), which considerably reduced the total costs for diagnosis and for a 3-year treatment from EUR 1,112.30 to 521.77 per patient. Conclusions The results from this real-life study show that SPT is less expensive than allergen molecule-based diagnostic testing, but molecular diagnosis allowed more precise prescription of immunotherapy which substantially reduced treatment costs and combined costs for diagnosis and treatment. PMID:28654920

Data Fusion for Enhanced Aircraft Engine Prognostics and Health Management

NASA Technical Reports Server (NTRS)

Volponi, Al

2005-01-01

Aircraft gas-turbine engine data is available from a variety of sources, including on-board sensor measurements, maintenance histories, and component models. An ultimate goal of Propulsion Health Management (PHM) is to maximize the amount of meaningful information that can be extracted from disparate data sources to obtain comprehensive diagnostic and prognostic knowledge regarding the health of the engine. Data fusion is the integration of data or information from multiple sources for the achievement of improved accuracy and more specific inferences than can be obtained from the use of a single sensor alone. The basic tenet underlying the data/ information fusion concept is to leverage all available information to enhance diagnostic visibility, increase diagnostic reliability and reduce the number of diagnostic false alarms. This report describes a basic PHM data fusion architecture being developed in alignment with the NASA C-17 PHM Flight Test program. The challenge of how to maximize the meaningful information extracted from disparate data sources to obtain enhanced diagnostic and prognostic information regarding the health and condition of the engine is the primary goal of this endeavor. To address this challenge, NASA Glenn Research Center, NASA Dryden Flight Research Center, and Pratt & Whitney have formed a team with several small innovative technology companies to plan and conduct a research project in the area of data fusion, as it applies to PHM. Methodologies being developed and evaluated have been drawn from a wide range of areas including artificial intelligence, pattern recognition, statistical estimation, and fuzzy logic. This report will provide a chronology and summary of the work accomplished under this research contract.

Turbofan Noise Studied in Unique Model Research Program in NASA Glenn's 9- by 15-Foot Low-Speed Wind Tunnel

NASA Technical Reports Server (NTRS)

Hughes, Christopher E.

2001-01-01

A comprehensive aeroacoustic research program called the Source Diagnostic Test was recently concluded in NASA Glenn Research Center's 9- by 15-Foot Low Speed Wind Tunnel. The testing involved representatives from Glenn, NASA Langley Research Center, GE Aircraft Engines, and the Boeing Company. The technical objectives of this research were to identify the different source mechanisms of noise in a modern, high-bypass turbofan aircraft engine through scale-model testing and to make detailed acoustic and aerodynamic measurements to more fully understand the physics of how turbofan noise is generated.

Sequential Test Strategies for Multiple Fault Isolation

NASA Technical Reports Server (NTRS)

Shakeri, M.; Pattipati, Krishna R.; Raghavan, V.; Patterson-Hine, Ann; Kell, T.

1997-01-01

In this paper, we consider the problem of constructing near optimal test sequencing algorithms for diagnosing multiple faults in redundant (fault-tolerant) systems. The computational complexity of solving the optimal multiple-fault isolation problem is super-exponential, that is, it is much more difficult than the single-fault isolation problem, which, by itself, is NP-hard. By employing concepts from information theory and Lagrangian relaxation, we present several static and dynamic (on-line or interactive) test sequencing algorithms for the multiple fault isolation problem that provide a trade-off between the degree of suboptimality and computational complexity. Furthermore, we present novel diagnostic strategies that generate a static diagnostic directed graph (digraph), instead of a static diagnostic tree, for multiple fault diagnosis. Using this approach, the storage complexity of the overall diagnostic strategy reduces substantially. Computational results based on real-world systems indicate that the size of a static multiple fault strategy is strictly related to the structure of the system, and that the use of an on-line multiple fault strategy can diagnose faults in systems with as many as 10,000 failure sources.

Meta-analysis of diagnostic test data: a bivariate Bayesian modeling approach.

PubMed

Verde, Pablo E

2010-12-30

In the last decades, the amount of published results on clinical diagnostic tests has expanded very rapidly. The counterpart to this development has been the formal evaluation and synthesis of diagnostic results. However, published results present substantial heterogeneity and they can be regarded as so far removed from the classical domain of meta-analysis, that they can provide a rather severe test of classical statistical methods. Recently, bivariate random effects meta-analytic methods, which model the pairs of sensitivities and specificities, have been presented from the classical point of view. In this work a bivariate Bayesian modeling approach is presented. This approach substantially extends the scope of classical bivariate methods by allowing the structural distribution of the random effects to depend on multiple sources of variability. Meta-analysis is summarized by the predictive posterior distributions for sensitivity and specificity. This new approach allows, also, to perform substantial model checking, model diagnostic and model selection. Statistical computations are implemented in the public domain statistical software (WinBUGS and R) and illustrated with real data examples. Copyright © 2010 John Wiley & Sons, Ltd.

Evidence synthesis to inform model-based cost-effectiveness evaluations of diagnostic tests: a methodological review of health technology assessments.

PubMed

Shinkins, Bethany; Yang, Yaling; Abel, Lucy; Fanshawe, Thomas R

2017-04-14

Evaluations of diagnostic tests are challenging because of the indirect nature of their impact on patient outcomes. Model-based health economic evaluations of tests allow different types of evidence from various sources to be incorporated and enable cost-effectiveness estimates to be made beyond the duration of available study data. To parameterize a health-economic model fully, all the ways a test impacts on patient health must be quantified, including but not limited to diagnostic test accuracy. We assessed all UK NIHR HTA reports published May 2009-July 2015. Reports were included if they evaluated a diagnostic test, included a model-based health economic evaluation and included a systematic review and meta-analysis of test accuracy. From each eligible report we extracted information on the following topics: 1) what evidence aside from test accuracy was searched for and synthesised, 2) which methods were used to synthesise test accuracy evidence and how did the results inform the economic model, 3) how/whether threshold effects were explored, 4) how the potential dependency between multiple tests in a pathway was accounted for, and 5) for evaluations of tests targeted at the primary care setting, how evidence from differing healthcare settings was incorporated. The bivariate or HSROC model was implemented in 20/22 reports that met all inclusion criteria. Test accuracy data for health economic modelling was obtained from meta-analyses completely in four reports, partially in fourteen reports and not at all in four reports. Only 2/7 reports that used a quantitative test gave clear threshold recommendations. All 22 reports explored the effect of uncertainty in accuracy parameters but most of those that used multiple tests did not allow for dependence between test results. 7/22 tests were potentially suitable for primary care but the majority found limited evidence on test accuracy in primary care settings. The uptake of appropriate meta-analysis methods for synthesising evidence on diagnostic test accuracy in UK NIHR HTAs has improved in recent years. Future research should focus on other evidence requirements for cost-effectiveness assessment, threshold effects for quantitative tests and the impact of multiple diagnostic tests.

Ultrasound as Diagnostic Tool for Diaphragmatic Myoclonus

PubMed Central

Llaneza Ramos, Vesper Fe Marie; Considine, Elaine; Karp, Barbara I.; Lungu, Codrin; Alter, Katharine; Hallett, Mark

2015-01-01

Background Diaphragmatic myoclonus is a rare disorder of repetitive diaphragmatic contractions, acknowledged to be a spectrum that includes psychogenic features. Electromyography has been the diagnostic tool most commonly used in the literature. Methods To test if we could perform a noninvasive technique to delineate the diaphragm as the source of abnormal movements and demonstrate distractibility and entrainability, we used B-mode ultrasound in a patient with diaphragmatic myoclonus. Results Ultrasound imaging clearly delineated the diaphragm as the source of her abdominal movements. We were able to demonstrate entrainability of the diaphragm to hand tapping to a prescribed rhythm set by examiner. Conclusion We recommend the use of ultrasound as a noninvasive, convenient diagnostic tool for further studies of diaphragmatic myoclonus. We agree with previous findings that diaphragmatic myoclonus may be a functional movement disorder, as evidenced by distractibility and entrainability demonstrated on real-time video with ultrasonography. PMID:27430001

Detection of clinically relevant copy-number variants by exome sequencing in a large cohort of genetic disorders

PubMed Central

Pfundt, Rolph; del Rosario, Marisol; Vissers, Lisenka E.L.M.; Kwint, Michael P.; Janssen, Irene M.; de Leeuw, Nicole; Yntema, Helger G.; Nelen, Marcel R.; Lugtenberg, Dorien; Kamsteeg, Erik-Jan; Wieskamp, Nienke; Stegmann, Alexander P.A.; Stevens, Servi J.C.; Rodenburg, Richard J.T.; Simons, Annet; Mensenkamp, Arjen R.; Rinne, Tuula; Gilissen, Christian; Scheffer, Hans; Veltman, Joris A.; Hehir-Kwa, Jayne Y.

2017-01-01

Purpose: Copy-number variation is a common source of genomic variation and an important genetic cause of disease. Microarray-based analysis of copy-number variants (CNVs) has become a first-tier diagnostic test for patients with neurodevelopmental disorders, with a diagnostic yield of 10–20%. However, for most other genetic disorders, the role of CNVs is less clear and most diagnostic genetic studies are generally limited to the study of single-nucleotide variants (SNVs) and other small variants. With the introduction of exome and genome sequencing, it is now possible to detect both SNVs and CNVs using an exome- or genome-wide approach with a single test. Methods: We performed exome-based read-depth CNV screening on data from 2,603 patients affected by a range of genetic disorders for which exome sequencing was performed in a diagnostic setting. Results: In total, 123 clinically relevant CNVs ranging in size from 727 bp to 15.3 Mb were detected, which resulted in 51 conclusive diagnoses and an overall increase in diagnostic yield of ~2% (ranging from 0 to –5.8% per disorder). Conclusions: This study shows that CNVs play an important role in a broad range of genetic disorders and that detection via exome-based CNV profiling results in an increase in the diagnostic yield without additional testing, bringing us closer to single-test genomics. Genet Med advance online publication 27 October 2016 PMID:28574513

Methodology and preliminary results of a systematic literature review of ante-mortem and post-mortem diagnostic tests for bovine tuberculosis.

PubMed

Downs, Sara H; Parry, Jessica E; Upton, Paul A; Broughan, Jennifer M; Goodchild, Anthony V; Nuñez-Garcia, Javier; Greiner, Matthias; Abernethy, Darrell A; Cameron, Angus R; Cook, Alasdair J; de la Rua-Domenech, Ricardo; Gunn, Jane; Pritchard, Elizabeth; Rhodes, Shelley; Rolfe, Simon; Sharp, Michael; Vordermeier, H Martin; Watson, Eamon; Welsh, Michael; Whelan, Adam O; Woolliams, John A; More, Simon J; Clifton-Hadley, Richard S

2018-05-01

A systematic review was conducted to identify studies with data for statistical meta-analyses of sensitivity (Se) and specificity (Sp) of ante-mortem and post-mortem diagnostic tests for bovine tuberculosis (bTB) in cattle. Members of a working group (WG) developed and tested search criteria and developed a standardised two-stage review process, to identify primary studies with numerator and denominator data for test performance and an agreed range of covariate data. No limits were applied to year, language, region or type of test in initial searches of electronic databases. In stage 1, titles and available abstracts were reviewed. References that complied with stage 1 selection criteria were reviewed in entirety and agreed data were extracted from references that complied with stage 2 selection criteria. At stage 1, 9782 references were reviewed and 261 (2.6%) passed through to stage 2 where 215 English language references were each randomly allocated to two of 18 WG reviewers and 46 references in other languages were allocated to native speakers. Agreement regarding eligibility between reviewers of the same reference at stage 2 was moderate (Kappa statistic = 0.51) and a resolution procedure was conducted. Only 119 references (published 1934-2009) were identified with eligible performance estimates for one or more of 14 different diagnostic test types; despite a comprehensive search strategy and the global impact of bTB. Searches of electronic databases for diagnostic test performance data were found to be nonspecific with regard to identifying references with diagnostic test Se or Sp data. Guidelines for the content of abstracts to research papers reporting diagnostic test performance are presented. The results of meta-analyses of the sensitivity and specificity of the tests, and of an evaluation of the methodological quality of the source references, are presented in accompanying papers (Nuñez-Garcia et al., 2017; Downs et al., 2017). Copyright © 2017. Published by Elsevier B.V.

Fan Noise Source Diagnostic Test: Tone Modal Structure Results

NASA Technical Reports Server (NTRS)

Heidelberg, Laurence J.

2002-01-01

This investigation is part of a test series that was extremely comprehensive and included aerodynamic and acoustic testing of a fan stage using two different fan rotors and three different stator designs. The test series is known as the Source Diagnostic Test (SDT) and was conducted by NASA Glenn as part of the Advanced Subsonic Technology (AST) Noise Reduction Program. Tone mode measurements of one of the rotors with three different stators were made. The stator designs involve changes in vane count and sweep at constant solidity. The results of both inlet and exhaust tone mode measurements are presented in terms of mode power for both circumferential and radial mode orders. The results show benefits of vane sweep to be large, up to 13 dB in total tone power. At many conditions, the increase in power due to cutting on the rotor/stator interaction is more than offset by vane sweep. The rotor locked mode is shown as an important contributor to tone power when the blade tip speed is near and above Mach one. This is most evident in the inlet when the direct rotor field starts to cut on.

Comparative Soot Diagnostics Experiment Looks at the Smoky World of Microgravity Combustion

NASA Technical Reports Server (NTRS)

Urban, David L.; Griffin, DeVon W.; Gard, Melissa Y.

1997-01-01

From an economic standpoint, soot is one of the most important combustion intermediates and products. It is a major industrial product and is the dominant medium for radiant heat transport in most flames used to generate heat and power. The nonbuoyant structure of most flames of practical interest (turbulent flames) makes the understanding of soot processes in microgravity flames important to our ability to predict fire behavior on Earth. In addition, fires in spacecraft are considered a credible possibility. To respond to this risk, NASA has flown fire (or smoke) detectors on Skylab and the space shuttles and included them in the International Space Station design. The design of these detectors, however, was based entirely on normal gravity (1g) data. The detector used in the shuttle fleet is an ionization detector, whereas the system planned for the space station uses forward scattering of near-infrared light. The ionization detector, which is similar to smoke detectors used in homes, has a comparative advantage for submicron particulates. In fact, the space shuttle model uses a separation system that makes it blind to particles larger than a micron (believed to be dust). In the larger size range, the lightscattering detector is most sensitive. Without microgravity smoke data, the difference in the particle size sensitivities of the two detectors cannot be evaluated. As part of the Comparative Soot Diagnostics (CSD) experiment, these systems were tested to determine their response to particulates generated during long periods of low gravity. This experiment provided the first such measurements toward understanding soot processes on Earth and for designing and implementing improved spacecraft smoke detection systems. The objectives of CSD were to examine how particulates form from a variety of sources and to quantify the performance of several diagnostic techniques. The sources tested included four overheated materials (paper, silicone rubber, Teflon-coated (DuPont) wire, and Kapton-coated (DuPont) wires), each tested at three heating rates, and a candle tested at three air velocities. Paper, silicone rubber, and wire insulation, materials found in spacecraft crew cabins, were selected because of their different smoke properties. The candle yielded hydrocarbon soot typical of many 1g flames. Four diagnostic techniques were employed: thermophoretic sampling collected particulates for size analysis; laser light extinction measurements near the source tallied total particulate production; and laser light scattering and ionization detector measurements far from the particulate source provided data for evaluating the performance of smoke detection systems for these particulate sources.

Image quality enhancement for skin cancer optical diagnostics

NASA Astrophysics Data System (ADS)

Bliznuks, Dmitrijs; Kuzmina, Ilona; Bolocko, Katrina; Lihachev, Alexey

2017-12-01

The research presents image quality analysis and enhancement proposals in biophotonic area. The sources of image problems are reviewed and analyzed. The problems with most impact in biophotonic area are analyzed in terms of specific biophotonic task - skin cancer diagnostics. The results point out that main problem for skin cancer analysis is the skin illumination problems. Since it is often not possible to prevent illumination problems, the paper proposes image post processing algorithm - low frequency filtering. Practical results show diagnostic results improvement after using proposed filter. Along that, filter do not reduces diagnostic results' quality for images without illumination defects. Current filtering algorithm requires empirical tuning of filter parameters. Further work needed to test the algorithm in other biophotonic applications and propose automatic filter parameter selection.

Towards non- and minimally instrumented, microfluidics-based diagnostic devices†

PubMed Central

Weigl, Bernhard; Domingo, Gonzalo; LaBarre, Paul; Gerlach, Jay

2009-01-01

In many health care settings, it is uneconomical, impractical, or unaffordable to maintain and access a fully equipped diagnostics laboratory. Examples include home health care, developing-country health care, and emergency situations in which first responders are dealing with pandemics or biowarfare agent release. In those settings, fully disposable diagnostic devices that require no instrument support, reagent, or significant training are well suited. Although the only such technology to have found widespread adoption so far is the immunochromatographic rapid assay strip test, microfluidics holds promise to expand the range of assay technologies that can be performed in formats similar to that of a strip test. In this paper, we review progress toward development of disposable, low-cost, easy-to-use microfluidics-based diagnostics that require no instrument at all. We also present examples of microfluidic functional elements—including mixers, separators, and detectors—as well as complete microfluidic devices that function entirely without any moving parts and external power sources. PMID:19023463

RF Negative Ion Source Development at IPP Garching

NASA Astrophysics Data System (ADS)

Kraus, W.; McNeely, P.; Berger, M.; Christ-Koch, S.; Falter, H. D.; Fantz, U.; Franzen, P.; Fröschle, M.; Heinemann, B.; Leyer, S.; Riedl, R.; Speth, E.; Wünderlich, D.

2007-08-01

IPP Garching is heavily involved in the development of an ion source for Neutral Beam Heating of the ITER Tokamak. RF driven ion sources have been successfully developed and are in operation on the ASDEX-Upgrade Tokamak for positive ion based NBH by the NB Heating group at IPP Garching. Building on this experience a RF driven H- ion source has been under development at IPP Garching as an alternative to the ITER reference design ion source. The number of test beds devoted to source development for ITER has increased from one (BATMAN) by the addition of two test beds (MANITU, RADI). This paper contains descriptions of the three test beds. Results on diagnostic development using laser photodetachment and cavity ringdown spectroscopy are given for BATMAN. The latest results for long pulse development on MANITU are presented including the to date longest pulse (600 s). As well, details of source modifications necessitated for pulses in excess of 100 s are given. The newest test bed RADI is still being commissioned and only technical details of the test bed are included in this paper. The final topic of the paper is an investigation into the effects of biasing the plasma grid.

Verification bias an underrecognized source of error in assessing the efficacy of medical imaging.

PubMed

Petscavage, Jonelle M; Richardson, Michael L; Carr, Robert B

2011-03-01

Diagnostic tests are validated by comparison against a "gold standard" reference test. When the reference test is invasive or expensive, it may not be applied to all patients. This can result in biased estimates of the sensitivity and specificity of the diagnostic test. This type of bias is called "verification bias," and is a common problem in imaging research. The purpose of our study is to estimate the prevalence of verification bias in the recent radiology literature. All issues of the American Journal of Roentgenology (AJR), Academic Radiology, Radiology, and European Journal of Radiology (EJR) between November 2006 and October 2009 were reviewed for original research articles mentioning sensitivity or specificity as endpoints. Articles were read to determine whether verification bias was present and searched for author recognition of verification bias in the design. During 3 years, these journals published 2969 original research articles. A total of 776 articles used sensitivity or specificity as an outcome. Of these, 211 articles demonstrated potential verification bias. The fraction of articles with potential bias was respectively 36.4%, 23.4%, 29.5%, and 13.4% for AJR, Academic Radiology, Radiology, and EJR. The total fraction of papers with potential bias in which the authors acknowledged this bias was 17.1%. Verification bias is a common and frequently unacknowledged source of error in efficacy studies of diagnostic imaging. Bias can often be eliminated by proper study design. When it cannot be eliminated, it should be estimated and acknowledged. Published by Elsevier Inc.

Limited-information goodness-of-fit testing of diagnostic classification item response models.

PubMed

Hansen, Mark; Cai, Li; Monroe, Scott; Li, Zhen

2016-11-01

Despite the growing popularity of diagnostic classification models (e.g., Rupp et al., 2010, Diagnostic measurement: theory, methods, and applications, Guilford Press, New York, NY) in educational and psychological measurement, methods for testing their absolute goodness of fit to real data remain relatively underdeveloped. For tests of reasonable length and for realistic sample size, full-information test statistics such as Pearson's X 2 and the likelihood ratio statistic G 2 suffer from sparseness in the underlying contingency table from which they are computed. Recently, limited-information fit statistics such as Maydeu-Olivares and Joe's (2006, Psychometrika, 71, 713) M 2 have been found to be quite useful in testing the overall goodness of fit of item response theory models. In this study, we applied Maydeu-Olivares and Joe's (2006, Psychometrika, 71, 713) M 2 statistic to diagnostic classification models. Through a series of simulation studies, we found that M 2 is well calibrated across a wide range of diagnostic model structures and was sensitive to certain misspecifications of the item model (e.g., fitting disjunctive models to data generated according to a conjunctive model), errors in the Q-matrix (adding or omitting paths, omitting a latent variable), and violations of local item independence due to unmodelled testlet effects. On the other hand, M 2 was largely insensitive to misspecifications in the distribution of higher-order latent dimensions and to the specification of an extraneous attribute. To complement the analyses of the overall model goodness of fit using M 2 , we investigated the utility of the Chen and Thissen (1997, J. Educ. Behav. Stat., 22, 265) local dependence statistic XLD2 for characterizing sources of misfit, an important aspect of model appraisal often overlooked in favour of overall statements. The XLD2 statistic was found to be slightly conservative (with Type I error rates consistently below the nominal level) but still useful in pinpointing the sources of misfit. Patterns of local dependence arising due to specific model misspecifications are illustrated. Finally, we used the M 2 and XLD2 statistics to evaluate a diagnostic model fit to data from the Trends in Mathematics and Science Study, drawing upon analyses previously conducted by Lee et al., (2011, IJT, 11, 144). © 2016 The British Psychological Society.

Tomographic diagnostic of the hydrogen beam from a negative ion source

NASA Astrophysics Data System (ADS)

Agostini, M.; Brombin, M.; Serianni, G.; Pasqualotto, R.

2011-10-01

In this paper the tomographic diagnostic developed to characterize the 2D density distribution of a particle beam from a negative ion source is described. In particular, the reliability of this diagnostic has been tested by considering the geometry of the source for the production of ions of deuterium extracted from an rf plasma (SPIDER). SPIDER is a low energy prototype negative ion source for the international thermonuclear experimental reactor (ITER) neutral beam injector, aimed at demonstrating the capability to create and extract a current of D- (H-) ions up to 50 A (60 A) accelerated at 100 kV. The ions are extracted over a wide surface (1.52×0.56m2) with a uniform plasma density which is prescribed to remain within 10% of the mean value. The main target of the tomographic diagnostic is the measurement of the beam uniformity with sufficient spatial resolution and of its evolution throughout the pulse duration. To reach this target, a tomographic algorithm based on the simultaneous algebraic reconstruction technique is developed and the geometry of the lines of sight is optimized so as to cover the whole area of the beam. Phantoms that reproduce different experimental beam configurations are simulated and reconstructed, and the role of the noise in the signals is studied. The simulated phantoms are correctly reconstructed and their two-dimensional spatial nonuniformity is correctly estimated, up to a noise level of 10% with respect to the signal.

Washington Hospital Center defends its position. Changing situation calls for a new approach.

PubMed

Botvin, J D

2000-01-01

Washington Hospital Center, in the nation's capital, found cardiac care, its leading source of revenue, challenged by new contenders. This launched an aggressive campaign directly at patients, encouraging them to use WHC's diagnostic testing services.

Quality of information accompanying on-line marketing of home diagnostic tests.

PubMed

Datta, Adrija K; Selman, Tara J; Kwok, Tony; Tang, Teresa; Khan, Khalid S

2008-01-01

To assess the quality of information provided to consumers by websites marketing medical home diagnostic tests. A cross-sectional analysis of a database developed from searching targeted websites. Data sources were websites written in English which marketed medical home diagnostic tests. A meta-search engine was used to identify the first 20 citations for each type of home diagnostic medical test. Relevant websites limited to those written in English were reviewed independently and in triplicate, with disputes resolved by two further reviewers. Information on the quality of these sites was extracted using a pre-piloted performer. 168 websites were suitable for inclusion in the review. The quality of these sites showed marked variation. Only 24 of 168 (14.2%) complied with at least three-quarters of the quality items and just over half (95 of 168, 56.5%) reported official approval or certification of the test. Information on accuracy of the test marketed was reported by 87 of 168 (51.7%) websites, with 15 of 168 (8.9%) providing a scientific reference. Instructions for use of the product were found in 97 of 168 (57.9%). However, the course of action to be taken after obtaining the test result was stated in only 63 of 168 (37.5%) for a positive result and 43 of 168 (25.5%) for a negative result. The quality of information posted on commercial websites marketing home tests online is unsatisfactory and potentially misleading for consumers.

Quality of information accompanying on-line marketing of home diagnostic tests

PubMed Central

Datta, Adrija K; Selman, Tara J; Kwok, Tony; Tang, Teresa; Khan, Khalid S

2008-01-01

Objective To assess the quality of information provided to consumers by websites marketing medical home diagnostic tests. Design A cross-sectional analysis of a database developed from searching targeted websites. Setting Data sources were websites written in English which marketed medical home diagnostic tests. Main outcome measures A meta-search engine was used to identify the first 20 citations for each type of home diagnostic medical test. Relevant websites limited to those written in English were reviewed independently and in triplicate, with disputes resolved by two further reviewers. Information on the quality of these sites was extracted using a pre-piloted performer. Results 168 websites were suitable for inclusion in the review. The quality of these sites showed marked variation. Only 24 of 168 (14.2%) complied with at least three-quarters of the quality items and just over half (95 of 168, 56.5%) reported official approval or certification of the test. Information on accuracy of the test marketed was reported by 87 of 168 (51.7%) websites, with 15 of 168 (8.9%) providing a scientific reference. Instructions for use of the product were found in 97 of 168 (57.9%). However, the course of action to be taken after obtaining the test result was stated in only 63 of 168 (37.5%) for a positive result and 43 of 168 (25.5%) for a negative result. Conclusions The quality of information posted on commercial websites marketing home tests online is unsatisfactory and potentially misleading for consumers. PMID:18263912

Interrogating the dynamics between power, knowledge and pregnant bodies in amniocentesis decision making.

PubMed

Markens, Susan; Browner, Carole H; Mabel Preloran, H

2010-01-01

A common assumption is that women who decline prenatal testing distrust biomedicine and trust embodied/experiential knowledge sources, while women who accept testing trust biomedicine and distrust embodied/experiential sources. Another major assumption about prenatal testing utilisation is that women who are open to abortion will undergo prenatal testing while those who are opposed to abortion will decline testing. Yet, previous research has produced inconsistent findings as to what, if anything, distinguishes women who accept or decline the offer of prenatal diagnosis. Analysing interviews with 147 pregnant women, this paper questions these assumptions about the role of abortion views and pregnant women's relative trust in various knowledge sources on their decisions to accept or decline an amniocentesis offer after a positive result on an initial diagnostic screening. We found that pregnant women's attitudes toward different knowledge sources were equally, if not more, important factors than abortion views in affecting whether individual women accepted or declined amniocentesis. At the same time, our data reveal that the relationship between 'expert' and 'lay' knowledge sources is often complex and synergistic.

CHALLENGES IN SETTING UP QUALITY CONTROL IN DIAGNOSTIC RADIOLOGY FACILITIES IN NIGERIA.

PubMed

Inyang, S O; Egbe, N O; Ekpo, E

2015-01-01

The Nigerian Nuclear Regulatory Authority (NNRA) was established to regulate and control the use of radioactive and radiation emitting sources in Nigeria. Quality control (QC) on diagnostic radiology equipment form part of the fundamental requirements for the authorization of diagnostic radiology facilities in the Country. Some quality control tests (output, exposure linearity and reproducibility) were measured on the x-ray machines in the facilities that took part in the study. Questionnaire was developed to evaluate the frequencies at which QC tests were conducted in the facilities and the challenges in setting up QC. Results show great variation in the values of the QC parameters measured. Inadequate cooperation by facilities management, lack of QC equipment and insufficient staff form the major challenges in setting up QC in the facilities under study. The responses on the frequencies at which QC tests should be conducted did not correspond to the recommended standards; indicating that personnel were not familiar with QC implementation and may require further training on QC.

A Comparison of Methods to Screen Middle School Students for Reading and Math Difficulties

ERIC Educational Resources Information Center

Nelson, Peter M.; Van Norman, Ethan R.; Lackner, Stacey K.

2016-01-01

The current study explored multiple ways in which middle schools can use and integrate data sources to predict proficiency on future high-stakes state achievement tests. The diagnostic accuracy of (a) prior achievement data, (b) teacher rating scale scores, (c) a composite score combining state test scores and rating scale responses, and (d) two…

Potential Biases Introduced by Conflating Screening and Diagnostic Testing in Colorectal Cancer Screening Surveillance

PubMed Central

Becker, Elizabeth A.; Griffith, Derek M.; West, Brady T.; Janz, Nancy K.; Resnicow, Ken; Morris, Arden M.

2015-01-01

Background Screening and post-symptomatic diagnostic testing are often conflated in cancer screening surveillance research. We examined the error in estimated colorectal cancer (CRC) screening prevalence due to the conflation of screening and diagnostic testing. Methods Using data from the 2008 National Health Interview Survey, we compared weighted prevalence estimates of the use of all testing (screening and diagnostic) and screening in at-risk adults, and calculated the overestimation of screening prevalence across socio-demographic groups. Results The population screening prevalence was overestimated by 23.3%, and the level of overestimation varied widely across socio-demographic groups (median 22.6%, mean 24.8%). The highest levels of overestimation were in non-Hispanic White females (27.4%), adults ages 50–54 (32.0%), and those with the highest socioeconomic vulnerability (low educational attainment (31.3%), low poverty ratio (32.5%), no usual source of health care (54.4%) and not insured (51.6%)) (all p-values < 0.001). Conclusions When the impetus for testing was not included, CRC screening prevalence was overestimated, and patterns of overestimation often aligned with social and economic vulnerability. These results are of concern to researchers who utilize survey data from the Behavioral Risk Factor Surveillance System (BRFSS) to assess cancer screening behaviors, as it is currently not designed to distinguish diagnostic testing from screening. Impact Surveillance research in cancer screening that does not consider the impetus for testing risks measurement error of screening prevalence, impeding progress toward improving population health. Ultimately, in order to craft relevant screening benchmarks and interventions, we must look beyond ‘what’ and ‘when’ and include ‘why.’ PMID:26491056

A study of interior noise levels, noise sources and transmission paths in light aircraft

NASA Technical Reports Server (NTRS)

Hayden, R. E.; Murray, B. S.; Theobald, M. A.

1983-01-01

The interior noise levels and spectral characteristics of 18 single-and twin-engine propeller-driven light aircraft, and source-path diagnosis of a single-engine aircraft which was considered representative of a large part of the fleet were studied. The purpose of the flight surveys was to measure internal noise levels and identify principal noise sources and paths under a carefully controlled and standardized set of flight procedures. The diagnostic tests consisted of flights and ground tests in which various parts of the aircraft, such as engine mounts, the engine compartment, exhaust pipe, individual panels, and the wing strut were instrumented to determine source levels and transmission path strengths using the transfer function technique. Predominant source and path combinations are identified. Experimental techniques are described. Data, transfer function calculations to derive source-path contributions to the cabin acoustic environment, and implications of the findings for noise control design are analyzed.

Requirements for diagnosis of malaria at different levels of the laboratory network in Africa.

PubMed

Long, Earl G

2009-06-01

The rapid increase of resistance to cheap, reliable antimalarials, the increasing cost of effective drugs, and the low specificity of clinical diagnosis has increased the need for more reliable diagnostic methods for malaria. The most commonly used and most reliable remains microscopic examination of stained blood smears, but this technique requires skilled personnel, precision instruments, and ideally a source of electricity. Microscopy has the advantage of enabling the examiner to identify the species, stage, and density of an infection. An alternative to microscopy is the rapid diagnostic test (RDT), which uses a labeled monoclonal antibody to detect circulating parasitic antigens. This test is most commonly used to detect Plasmodium falciparum infections and is available in a plastic cassette format. Both microscopy and RDTs should be available at all levels of laboratory service in endemic areas, but in peripheral laboratories with minimally trained staff, the RDT may be a more practical diagnostic method.

Laboratory testing for cytomegalovirus among pregnant women in the United States: a retrospective study using administrative claims data

PubMed Central

2012-01-01

Background Routine cytomegalovirus (CMV) screening during pregnancy is not recommended in the United States and the extent to which it is performed is unknown. Using a medical claims database, we computed rates of CMV-specific testing among pregnant women. Methods We used medical claims from the 2009 Truven Health MarketScan® Commercial databases. We computed CMV-specific testing rates using CPT codes. Results We identified 77,773 pregnant women, of whom 1,668 (2%) had a claim for CMV-specific testing. CMV-specific testing was significantly associated with older age, Northeast or urban residence, and a diagnostic code for mononucleosis. We identified 44 women with a diagnostic code for mononucleosis, of whom 14% had CMV-specific testing. Conclusions Few pregnant women had CMV-specific testing, suggesting that screening for CMV infection during pregnancy is not commonly performed. In the absence of national surveillance for CMV infections during pregnancy, healthcare claims are a potential source for monitoring practices of CMV-specific testing. PMID:23198949

Finding and applying evidence during clinical rounds: the "evidence cart".

PubMed

Sackett, D L; Straus, S E

1998-10-21

Physicians need easy access to evidence for clinical decisions while they care for patients but, to our knowledge, no investigators have assessed use of evidence during rounds with house staff. To determine if it was feasible to find and apply evidence during clinical rounds, using an "evidence cart" that contains multiple sources of evidence and the means for projecting and printing them. Descriptive feasibility study of use of evidence during 1 month (April 1997) and anonymous questionnaire (May 1997). General medicine inpatient service. Medical students, house staff, fellows, and attending consultant. Evidence cart that included 2 secondary sources developed by the department (critically appraised topics [CATs] and Redbook), Best Evidence, JAMA Rational Clinical Examination series, the Cochrane Library, MEDLINE, a physical examination textbook, a radiology anatomy textbook, and a Simulscope, which allows several people to listen simultaneously to the same signs on physical examination. Number of times sources were used, type of sources searched and success of searches, time needed to search, and whether the search affected patient care. The evidence cart was used 98 times, but could not be taken on bedside rounds because of its bulk; hard copies of several sources were taken instead. When the evidence cart was used during team rounds and student rounds, some sources could be accessed quickly enough (10.2-25.4 seconds) to be practical on our service. Of 98 searches, 79 (81%) sought evidence that could affect diagnostic and/or treatment decisions. Seventy-one (90%) of 79 searches regarding patient management were successful, and when assessed from the perspective of the most junior team members responsible for each patient's evaluation and management, 37 (52%) of the 71 successful searches confirmed their current or tentative diagnostic or treatment plans, 18 (25%) led to a new diagnostic skill, an additional test, or a new management decision, and 16 (23%) corrected a previous clinical skill, diagnostic test, or treatment. When the cart was removed, the perceived need for evidence rose sharply, but a search for it was carried out only 12% of the time (5 searches performed out of the 41 times evidence was needed). Making evidence quickly available to clinicians on a busy medical inpatient service using an evidence cart increased the extent to which evidence was sought and incorporated into patient care decisions.

Extreme ultraviolet spectroscopy diagnostics of low-temperature plasmas based on a sliced multilayer grating and glass capillary optics.

PubMed

Kantsyrev, V L; Safronova, A S; Williamson, K M; Wilcox, P; Ouart, N D; Yilmaz, M F; Struve, K W; Voronov, D L; Feshchenko, R M; Artyukov, I A; Vinogradov, A V

2008-10-01

New extreme ultraviolet (EUV) spectroscopic diagnostics of relatively low-temperature plasmas based on the application of an EUV spectrometer and fast EUV diodes combined with glass capillary optics is described. An advanced high resolution dispersive element sliced multilayer grating was used in the compact EUV spectrometer. For monitoring of the time history of radiation, filtered fast EUV diodes were used in the same spectral region (>13 nm) as the EUV spectrometer. The radiation from the plasma was captured by using a single inexpensive glass capillary that was transported onto the spectrometer entrance slit and EUV diode. The use of glass capillary optics allowed placement of the spectrometer and diodes behind the thick radiation shield outside the direction of a possible hard x-ray radiation beam and debris from the plasma source. The results of the testing and application of this diagnostic for a compact laser plasma source are presented. Examples of modeling with parameters of plasmas are discussed.

Greater Real-Life Diagnostic Efficacy of Allergen Molecule-Based Diagnosis for Prescription of Immunotherapy in an Area with Multiple Pollen Exposure.

PubMed

Saltabayeva, Ulbosin; Garib, Victoria; Morenko, Marina; Rosenson, Rafail; Ispayeva, Zhanat; Gatauova, Madina; Zulus, Loreta; Karaulov, Alexander; Gastager, Felix; Valenta, Rudolf

2017-01-01

Allergen molecule-based diagnosis has been suggested to facilitate the identification of disease-causing allergen sources and the prescription of allergen-specific immunotherapy (AIT). The aim of the current study was to compare allergen molecule-based IgE serology with allergen extract-based skin testing for the identification of the disease-causing allergen sources. The study was conducted in an area where patients are exposed to pollen from multiple sources (trees, grasses, and weeds) at the same time to compare the diagnostic efficiency of the 2 forms of diagnosis. Patients from Astana, Kazakhstan, who suffered from pollen-induced allergy (n = 95) were subjected to skin prick testing (SPT) with a local panel of tree pollen, grass pollen, and weed pollen allergen extracts and IgE antibodies specific for marker allergen molecules (nArt v 1, nArt v 3, rAmb a 1, rPhl p 1, rPhl p 5, rBet v 1) were measured by ImmunoCAP. Direct and indirect costs for diagnosis based on SPT and marker allergen-based IgE serology as well as direct costs for immunotherapy depending on SPT and serological test results were calculated. The costs for SPT-based diagnosis per patient were lower than the costs for allergen molecule-based IgE serology. However, allergen molecule-based serology was more precise in detecting the disease-causing allergen sources. A lower number of immunotherapy treatments (n = 119) was needed according to molecular diagnosis as compared to extract-based diagnosis (n = 275), which considerably reduced the total costs for diagnosis and for a 3-year treatment from EUR 1,112.30 to 521.77 per patient. The results from this real-life study show that SPT is less expensive than allergen molecule-based diagnostic testing, but molecular diagnosis allowed more precise prescription of immunotherapy which substantially reduced treatment costs and combined costs for diagnosis and treatment. © 2017 The Author(s) Published by S. Karger AG, Basel.

First beam measurements on the vessel for extraction and source plasma analyses (VESPA) at the Rutherford Appleton Laboratory (RAL)

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

Lawrie, Scott R., E-mail: scott.lawrie@stfc.ac.uk; John Adams Institute for Accelerator Science, Department of Physics, University of Oxford; Faircloth, Daniel C.

2015-04-08

In order to facilitate the testing of advanced H{sup −} ion sources for the ISIS and Front End Test Stand (FETS) facilities at the Rutherford Appleton Laboratory (RAL), a Vessel for Extraction and Source Plasma Analyses (VESPA) has been constructed. This will perform the first detailed plasma measurements on the ISIS Penning-type H{sup −} ion source using emission spectroscopic techniques. In addition, the 30-year-old extraction optics are re-designed from the ground up in order to fully transport the beam. Using multiple beam and plasma diagnostics devices, the ultimate aim is improve H{sup −} production efficiency and subsequent transport for eithermore » long-term ISIS user operations or high power FETS requirements. The VESPA will also accommodate and test a new scaled-up Penning H{sup −} source design. This paper details the VESPA design, construction and commissioning, as well as initial beam and spectroscopy results.« less

Tests sérologiques dans la maladie cœliaque

PubMed Central

Rashid, Mohsin; Lee, Jennie

2016-01-01

Résumé Objectif Répondre aux questions souvent posées par les généralistes et aux difficultés auxquelles ils font face lorsqu’ils prescrivent des tests sérologiques pour la maladie cœliaque et fournir des conseils pratiques pour aider à interpréter les résultats des tests. Sources de l’information Une recherche a été effectuée dans MEDLINE pour les lignes directrices sur le diagnostic et la prise en charge de la maladie cœliaque publiées en anglais entre 2000 et 2015 par des organisations professionnelles de gastro-entérologie. Message principal Pour dépister la maladie cœliaque, le dosage de l’anticorps immunoglobuline A (IgA) anti-transglutaminase tissulaire est le test de choix. Il faut mesurer le taux sérique d’IgA totale afin d’écarter un déficit sélectif en IgA et d’éviter les faux négatifs. Les patients dont le test sérologique est positif doivent être recommandés à un gastro-entérologue pour subir des biopsies de l’intestin grêle par endoscopie afin de confirmer le diagnostic. Le typage des antigènes des leucocytes humains DQ2 et DQ8 peut aider à écarter le diagnostic. Un régime sans gluten ne doit pas être entrepris avant que le diagnostic de maladie cœliaque soit confirmé. Conclusion Les tests sérologiques sont très utiles pour confirmer les soupçons d’une maladie cœliaque. Le diagnostic précoce est essentiel pour prévenir les complications liées à la maladie cœliaque.

An objective method and measuring equipment for noise control and acoustic diagnostics of motorcars. [acoustic diagnostics on automobile engines

NASA Technical Reports Server (NTRS)

Kacprowski, J.; Motylewski, J.; Miazga, J.

1974-01-01

An objective method and apparatus for noise control and acoustic diagnostics of motorcar engines are reported. The method and apparatus let us know whether the noisiness of the vehicle under test exceeds the admissible threshold levels given by appropriate standards and if so what is the main source of the excessive noise. The method consists in measuring both the overall noise level and the sound pressure levels in definite frequency bands while the engine speed is controlled as well and may be fixed at prescribed values. Whenever the individually adjusted threshold level has been exceeded in any frequency band, a self-sustaining control signal is sent.

2D imaging X-ray diagnostic for measuring the current density distribution in a wide-area electron beam produced in a multiaperture diode with plasma cathode

NASA Astrophysics Data System (ADS)

Kurkuchekov, V.; Kandaurov, I.; Trunev, Y.

2018-05-01

A simple and inexpensive X-ray diagnostic tool was designed for measuring the cross-sectional current density distribution in a low-relativistic pulsed electron beam produced in a source based on an arc-discharge plasma cathode and multiaperture diode-type electron optical system. The beam parameters were as follows: Uacc = 50–110 kV, Ibeam = 20–100 A, τbeam = 0.1–0.3 ms. The beam effective diameter was ca. 7 cm. Based on a pinhole camera, the diagnostic allows one to obtain a 2D profile of electron beam flux distribution on a flat metal target in a single shot. The linearity of the diagnostic system response to the electron flux density was established experimentally. Spatial resolution of the diagnostic was also estimated in special test experiments. The optimal choice of the main components of the diagnostic technique is discussed.

Overdiagnosis across medical disciplines: a scoping review

PubMed Central

de Groot, Joris A H; Reitsma, Johannes B; Moons, Karel G M; Hooft, Lotty; Naaktgeboren, Christiana A

2017-01-01

Objective To provide insight into how and in what clinical fields overdiagnosis is studied and give directions for further applied and methodological research. Design Scoping review. Data sources Medline up to August 2017. Study selection All English studies on humans, in which overdiagnosis was discussed as a dominant theme. Data extraction Studies were assessed on clinical field, study aim (ie, methodological or non-methodological), article type (eg, primary study, review), the type and role of diagnostic test(s) studied and the context in which these studies discussed overdiagnosis. Results From 4896 studies, 1851 were included for analysis. Half of all studies on overdiagnosis were performed in the field of oncology (50%). Other prevalent clinical fields included mental disorders, infectious diseases and cardiovascular diseases accounting for 9%, 8% and 6% of studies, respectively. Overdiagnosis was addressed from a methodological perspective in 20% of studies. Primary studies were the most common article type (58%). The type of diagnostic tests most commonly studied were imaging tests (32%), although these were predominantly seen in oncology and cardiovascular disease (84%). Diagnostic tests were studied in a screening setting in 43% of all studies, but as high as 75% of all oncological studies. The context in which studies addressed overdiagnosis related most frequently to its estimation, accounting for 53%. Methodology on overdiagnosis estimation and definition provided a source for extensive discussion. Other contexts of discussion included definition of disease, overdiagnosis communication, trends in increasing disease prevalence, drivers and consequences of overdiagnosis, incidental findings and genomics. Conclusions Overdiagnosis is discussed across virtually all clinical fields and in different contexts. The variability in characteristics between studies and lack of consensus on overdiagnosis definition indicate the need for a uniform typology to improve coherence and comparability of studies on overdiagnosis. PMID:29284720

A systematic review and meta-analysis of the diagnostic accuracy of point-of-care tests for the detection of hyperketonemia in dairy cows.

PubMed

Tatone, Elise H; Gordon, Jessica L; Hubbs, Jessie; LeBlanc, Stephen J; DeVries, Trevor J; Duffield, Todd F

2016-08-01

Several rapid tests for use on farm have been validated for the detection of hyperketonemia (HK) in dairy cattle, however the reported sensitivity and specificity of each method varies and no single study has compared them all. Meta-analysis of diagnostic test accuracy is becoming more common in human medical literature but there are few veterinary examples. The objective of this work was to perform a systematic review and meta-analysis to determine the point-of-care testing method with the highest combined sensitivity and specificity, the optimal threshold for each method, and to identify gaps in the literature. A comprehensive literature search resulted in 5196 references. After removing duplicates and performing relevance screening, 23 studies were included for the qualitative synthesis and 18 for the meta-analysis. The three index tests evaluated in the meta-analysis were: the Precision Xtra(®) handheld device measuring beta-hydroxybutyrate (BHB) concentration in whole blood, and Ketostix(®) and KetoTest(®) semi-quantitative strips measuring the concentration of acetoacetate in urine and BHB in milk, respectively. The diagnostic accuracy of the 3 index tests relative to the reference standard measurement of BHB in serum or whole blood between 1.0-1.4mmol/L was compared using the hierarchical summary receiver operator characteristic (HSROC) method. Subgroup analysis was conducted for each index test to examine the accuracy at different thresholds. The impact of the reference standard threshold, the reference standard method, the prevalence of HK in the population, the primary study source and risk of bias of the primary study was explored using meta-regression. The Precision Xtra(®) device had the highest summary sensitivity in whole blood BHB at 1.2mmol/L, 94.8% (CI95%: 92.6-97.0), and specificity, 97.5% (CI95%: 96.9-98.1). The threshold employed (1.2-1.4mmol/L) did not impact the diagnostic accuracy of the test. The Ketostix(®) and KetoTest(®) strips had the highest summary sensitivity and specificity when the trace and weak positive thresholds were used, respectively. Controlling for the source of publication, HK prevalence and reference standard employed did not impact the estimated sensitivity and specificity of the tests. Including only peer-reviewed studies reduced the number of primary studies evaluating the Precision Xtra(®) by 43% and Ketostix(®) by 33%. Diagnosing HK with blood, urine or milk are valid options, however, the diagnostic inaccuracy of urine and milk should be considered when making economic and treatment decisions. Copyright © 2016 Elsevier B.V. All rights reserved.

Diagnostic accuracy of level 3 portable sleep tests versus level 1 polysomnography for sleep-disordered breathing: a systematic review and meta-analysis

PubMed Central

El Shayeb, Mohamed; Topfer, Leigh-Ann; Stafinski, Tania; Pawluk, Lawrence; Menon, Devidas

2014-01-01

Background: Greater awareness of sleep-disordered breathing and rising obesity rates have fueled demand for sleep studies. Sleep testing using level 3 portable devices may expedite diagnosis and reduce the costs associated with level 1 in-laboratory polysomnography. We sought to assess the diagnostic accuracy of level 3 testing compared with level 1 testing and to identify the appropriate patient population for each test. Methods: We conducted a systematic review and meta-analysis of comparative studies of level 3 versus level 1 sleep tests in adults with suspected sleep-disordered breathing. We searched 3 research databases and grey literature sources for studies that reported on diagnostic accuracy parameters or disease management after diagnosis. Two reviewers screened the search results, selected potentially relevant studies and extracted data. We used a bivariate mixed-effects binary regression model to estimate summary diagnostic accuracy parameters. Results: We included 59 studies involving a total of 5026 evaluable patients (mostly patients suspected of having obstructive sleep apnea). Of these, 19 studies were included in the meta-analysis. The estimated area under the receiver operating characteristics curve was high, ranging between 0.85 and 0.99 across different levels of disease severity. Summary sensitivity ranged between 0.79 and 0.97, and summary specificity ranged between 0.60 and 0.93 across different apnea–hypopnea cut-offs. We saw no significant difference in the clinical management parameters between patients who underwent either test to receive their diagnosis. Interpretation: Level 3 portable devices showed good diagnostic performance compared with level 1 sleep tests in adult patients with a high pretest probability of moderate to severe obstructive sleep apnea and no unstable comorbidities. For patients suspected of having other types of sleep-disordered breathing or sleep disorders not related to breathing, level 1 testing remains the reference standard. PMID:24218531

Feline Genetics: Clinical Applications and Genetic Testing

PubMed Central

Lyons, Leslie A.

2010-01-01

DNA testing for domestic cat diseases and appearance traits is a rapidly growing asset for veterinary medicine. Approximately thirty-three genes contain fifty mutations that cause feline health problems or alterations in the cat’s appearance. A variety of commercial laboratories can now perform cat genetic diagnostics, allowing both the veterinary clinician and the private owner to obtain DNA test results. DNA is easily obtained from a cat via a buccal swab using a standard cotton bud or cytological brush, allowing DNA samples to be easily sent to any laboratory in the world. The DNA test results identify carriers of the traits, predict the incidence of traits from breeding programs, and influence medical prognoses and treatments. An overall goal of identifying these genetic mutations is the correction of the defect via gene therapies and designer drug therapies. Thus, genetic testing is an effective preventative medicine and a potential ultimate cure. However, genetic diagnostic tests may still be novel for many veterinary practitioners and their application in the clinical setting needs to have the same scrutiny as any other diagnostic procedure. This article will review the genetic tests for the domestic cat, potential sources of error for genetic testing, and the pros and cons of DNA results in veterinary medicine. Highlighted are genetic tests specific to the individual cat, which are a part of the cat’s internal genome. PMID:21147473

Feline genetics: clinical applications and genetic testing.

PubMed

Lyons, Leslie A

2010-11-01

DNA testing for domestic cat diseases and appearance traits is a rapidly growing asset for veterinary medicine. Approximately 33 genes contain 50 mutations that cause feline health problems or alterations in the cat's appearance. A variety of commercial laboratories can now perform cat genetic diagnostics, allowing both the veterinary clinician and the private owner to obtain DNA test results. DNA is easily obtained from a cat via a buccal swab with a standard cotton bud or cytological brush, allowing DNA samples to be easily sent to any laboratory in the world. The DNA test results identify carriers of the traits, predict the incidence of traits from breeding programs, and influence medical prognoses and treatments. An overall goal of identifying these genetic mutations is the correction of the defect via gene therapies and designer drug therapies. Thus, genetic testing is an effective preventative medicine and a potential ultimate cure. However, genetic diagnostic tests may still be novel for many veterinary practitioners and their application in the clinical setting needs to have the same scrutiny as any other diagnostic procedure. This article will review the genetic tests for the domestic cat, potential sources of error for genetic testing, and the pros and cons of DNA results in veterinary medicine. Highlighted are genetic tests specific to the individual cat, which are a part of the cat's internal genome. Copyright © 2010 Elsevier Inc. All rights reserved.

Special Physical Examination Tests for Superior Labrum Anterior-Posterior Shoulder Tears: An Examination of Clinical Usefulness

PubMed Central

Sandrey, Michelle A.

2013-01-01

Reference/Citation: Calvert E, Chambers GK, Regan W, Hawkins RH, Leith JM. Special physical examination tests for superior labrum anterior-posterior shoulder injuries are clinically limited and invalid: a diagnostic systematic review. J Clin Epidemiol. 2009;62(5):558–563. Clinical Question: The systematic review focused on diagnostic accuracy studies to determine if evidence was sufficient to support the use of superior labrum anterior-posterior (SLAP) physical examination tests as valid and reliable. The primary question was whether there was sufficient evidence in the published literature to support the use of SLAP physical examination tests as valid and reliable diagnostic test procedures. Data Sources: Studies published in English were identified through database searches on MEDLINE, EMBASE, and the Cochrane database (1970–2004) using the search term SLAP lesions. The medical subject headings of arthroscopy, shoulder joint, and athletic injuries were combined with test or testing, physical examination, and sensitivity and specificity to locate additional sources. Other sources were identified by rereviewing the reference lists of included studies and review articles. Study Selection: Studies were eligible based on the following criteria: (1) published in English, (2) focused on the physical examination of SLAP lesions, and (3) presented original data. A study was excluded if the article was limited to a clinical description of 1 or more special tests without any research focus to provide clinical accuracy data or if it did not focus on the topic. Data Extraction: The abstracts that were located through the search strategies were reviewed, and potentially relevant abstracts were selected. Strict epidemiologic methods were used to obtain and collate all relevant studies; the authors developed a study questionnaire to record study name, year of publication, study design, sample size, and statistics. Validity of the diagnostic test study was determined by applying the 5 criteria proposed by Calvert et al. If the study met the inclusion and validity criteria, 95% confidence intervals were calculated for each sensitivity, specificity, and positive and negative likelihood ratio reported. No specific information was provided about the procedure if the reviewers disagreed on how the evaluation criteria were applied. Main Results: The specific search criteria led to the identification of 29 full-text articles. The studies were reviewed, and inclusion and exclusion criteria were applied. This resulted in 14 excluded studies and 15 eligible studies for analysis. Of the 15 eligible studies, 1 evaluated only a single physical examination test for a SLAP lesion or biceps tendon injury, and 10 studies evaluated 2 to 6 physical examination tests for a SLAP lesion or biceps tendon injury. Nine studies reported sensitivities and specificities greater than 75%, 4 had sensitivities less than 75%, 3 had specificities less than 75%, 1 did not report sensitivity, and 2 did not report specificities. When validity was assessed for those 15 papers, only 1 study that evaluated the biceps tendon met the 5 critical appraisal criteria of Calvert et al and calculated 95% confidence intervals. When the Speed and Yergason tests were each compared with the gold standard (arthroscopy), the confidence intervals for the positive and negative likelihood ratios spanned 1. This indicated that the test result is unlikely to change the odds of having or not having the condition, respectively. Conclusions: The literature currently used as a reference for teaching in medical schools and continuing education lacks the necessary validity to help rule in or out a SLAP lesion or biceps tendon involvement. Based on the results from the systematic review conducted by Calvert et al, no tests clinically diagnose a SLAP lesion. This is a cause for concern as magnetic resonance imaging or magnetic resonance arthrography, which are frequently used to assess a possible SLAP lesion, may also have diagnostic flaws and may be cost prohibitive. Performing arthroscopy on every patient to rule the condition in or out is unethical, especially if a SLAP lesion is not present. More rigorous validity studies should be conducted for SLAP lesion physical examination tests using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool or Standards for Reporting Diagnostic Accuracy (STARD) criteria. PMID:23914880

A data-driven algorithm integrating clinical and laboratory features for the diagnosis and prognosis of necrotizing enterocolitis.

PubMed

Ji, Jun; Ling, Xuefeng B; Zhao, Yingzhen; Hu, Zhongkai; Zheng, Xiaolin; Xu, Zhening; Wen, Qiaojun; Kastenberg, Zachary J; Li, Ping; Abdullah, Fizan; Brandt, Mary L; Ehrenkranz, Richard A; Harris, Mary Catherine; Lee, Timothy C; Simpson, B Joyce; Bowers, Corinna; Moss, R Lawrence; Sylvester, Karl G

2014-01-01

Necrotizing enterocolitis (NEC) is a major source of neonatal morbidity and mortality. Since there is no specific diagnostic test or risk of progression model available for NEC, the diagnosis and outcome prediction of NEC is made on clinical grounds. The objective in this study was to develop and validate new NEC scoring systems for automated staging and prognostic forecasting. A six-center consortium of university based pediatric teaching hospitals prospectively collected data on infants under suspicion of having NEC over a 7-year period. A database comprised of 520 infants was utilized to develop the NEC diagnostic and prognostic models by dividing the entire dataset into training and testing cohorts of demographically matched subjects. Developed on the training cohort and validated on the blind testing cohort, our multivariate analyses led to NEC scoring metrics integrating clinical data. Machine learning using clinical and laboratory results at the time of clinical presentation led to two nec models: (1) an automated diagnostic classification scheme; (2) a dynamic prognostic method for risk-stratifying patients into low, intermediate and high NEC scores to determine the risk for disease progression. We submit that dynamic risk stratification of infants with NEC will assist clinicians in determining the need for additional diagnostic testing and guide potential therapies in a dynamic manner. http://translationalmedicine.stanford.edu/cgi-bin/NEC/index.pl and smartphone application upon request.

40 CFR 85.2222 - On-board diagnostic test procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... 85.2222 Section 85.2222 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF AIR POLLUTION FROM MOBILE SOURCES Emission Control System Performance... inspected at the EPA Docket No. A-94-21 at EPA's Air Docket (LE-131), Room 1500 M, 1st Floor, Waterside Mall...

Preliminary results from the Small Negative Ion Facility (SNIF) at CCFE

NASA Astrophysics Data System (ADS)

Zacks, J.; McAdams, R.; Booth, J.; Flinders, K.; Holmes, A. J. T.; Simmonds, M.; Stevens, B.; Stevenson, P.; Surrey, E.; Warder, S.; Whitehead, A.; Young, D.

2013-02-01

At Culham Centre for Fusion Energy, a new beam extraction test facility has been built with the purpose of studying and enhancing negative ion beam production and transport. The multipole hydrogen ion source is based on a RF generated plasma using a continuous 5kW power supply operating at the industrial standard frequency of 13.56MHz. The cylindrical source has a diameter of 30cm and a depth of 20cm, with a flat spiral antenna driving the source through a quartz window. The magnet configuration is arranged to produce a dipole filter field across the ion source close to the plasma grid. The plasma load is matched to the RF generator using a Pi matching network. The accelerator uses a single extraction aperture of 14mm diameter, with a biased insert for electron suppression. The accelerator is a triode design with a beam energy of up to 30kV. The beamline consists of a turbomolecular pumped vacuum tank with an instrumented beam dump and ports for additional diagnostics. The ITER Neutral Beam source operates with the enhancement of caesium, which, when scaled up to a reactor, will be heavily consumed. The small size of SNIF allows for fast turn around of modifications and alternative materials to caesium can be tested. A full description of the facility and planned diagnostics is given. Initial results are presented, including measurements and calculations of the plasma load on the RF generator, and beam extraction measurements.

Multiple dopant injection system for small rocket engines

NASA Technical Reports Server (NTRS)

Sakala, G. G.; Raines, N. G.

1992-01-01

The Diagnostics Test Facility (DTF) at NASA's Stennis Space Center (SSC) was designed and built to provide a standard rocket engine exhaust plume for use in the research and development of engine health monitoring instrumentation. A 1000 lb thrust class liquid oxygen (LOX)-gaseous hydrogen (GH2) fueled rocket engine is used as the subscale plume source to simulate the SSME during experimentation and instrument development. The ability of the DTF to provide efficient, and low cost test operations makes it uniquely suited for plume diagnostic experimentation. The most unique feature of the DTF is the Multiple Dopant Injection System (MDIS) that is used to seed the exhaust plume with the desired element or metal alloy. The dopant injection takes place at the fuel injector, yielding a very uniform and homogeneous distribution of the seeding material in the exhaust plume. The MDIS allows during a single test firing of the DTF, the seeding of the exhaust plume with up to three different dopants and also provides distilled water base lines between the dopants. A number of plume diagnostic-related experiments have already utilized the unique capabilities of the DTF.

Mycobacterium tuberculosis Contaminant Risk on Bone Marrow Aspiration Material from Iliac Bone Patients with Active Tuberculous Spondylitis.

PubMed

Rahyussalim, Ahmad Jabir; Kurniawati, Tri; Rukmana, Andriansjah

2016-01-01

There was a concern on Mycobacterium tuberculosis spreading to the bone marrow, when it was applied on tuberculous spine infection. This research aimed to study the probability of using autologous bone marrow as a source of mesenchymal stem cell for patients with tuberculous spondylitis. As many as nine patients with tuberculous spondylitis were used as samples. During the procedure, the vertebral lesion material and iliac bone marrow aspirates were obtained for acid fast staining, bacteria culture, and PCR (polymerase chain reaction) tests for Mycobacterium tuberculosis at the Clinical Microbiology Laboratory of Faculty of Medicine Universitas Indonesia. This research showed that there was a relationship between diagnostic confirmation of tuberculous spondylitis based on the PCR test and bacterial culture on the solid vertebral lesion material with the PCR test and bacterial culture from the bone marrow aspirates. If the diagnostic confirmation concluded positive results, then there was a higher probability that there would be a positive result for the bone marrow aspirates, so that it was not recommended to use autologous bone marrow as a source of mesenchymal stem cell for patients with tuberculous spondylitis unless the PCR and culture examination of the bone marrow showed a negative result.

21 CFR 1020.30 - Diagnostic x-ray systems and their major components.

Code of Federal Regulations, 2012 CFR

2012-04-01

... irradiation. Diagnostic source assembly means the tube housing assembly with a beam-limiting device attached. Diagnostic x-ray system means an x-ray system designed for irradiation of any part of the human body for the... diagnostic source assembly. Fluoroscopic irradiation time means the cumulative duration during an examination...

21 CFR 1020.30 - Diagnostic x-ray systems and their major components.

Code of Federal Regulations, 2013 CFR

2013-04-01

... irradiation. Diagnostic source assembly means the tube housing assembly with a beam-limiting device attached. Diagnostic x-ray system means an x-ray system designed for irradiation of any part of the human body for the... diagnostic source assembly. Fluoroscopic irradiation time means the cumulative duration during an examination...

21 CFR 1020.30 - Diagnostic x-ray systems and their major components.

Code of Federal Regulations, 2014 CFR

2014-04-01

... irradiation. Diagnostic source assembly means the tube housing assembly with a beam-limiting device attached. Diagnostic x-ray system means an x-ray system designed for irradiation of any part of the human body for the... diagnostic source assembly. Fluoroscopic irradiation time means the cumulative duration during an examination...

Students' understanding of direct current resistive electrical circuits

NASA Astrophysics Data System (ADS)

Engelhardt, Paula Vetter; Beichner, Robert J.

2004-01-01

Both high school and university students' reasoning regarding direct current resistive electric circuits often differ from the accepted explanations. At present, there are no standard diagnostic tests on electric circuits. Two versions of a diagnostic instrument were developed, each consisting of 29 questions. The information provided by this test can provide instructors with a way of evaluating the progress and conceptual difficulties of their students. The analysis indicates that students, especially females, tend to hold multiple misconceptions, even after instruction. During interviews, the idea that the battery is a constant source of current was used most often in answering the questions. Students tended to focus on the current in solving problems and to confuse terms, often assigning the properties of current to voltage and/or resistance.

Gas gun shock experiments with single-pulse x-ray phase contrast imaging and diffraction at the Advanced Photon Source

NASA Astrophysics Data System (ADS)

Luo, S. N.; Jensen, B. J.; Hooks, D. E.; Fezzaa, K.; Ramos, K. J.; Yeager, J. D.; Kwiatkowski, K.; Shimada, T.

2012-07-01

The highly transient nature of shock loading and pronounced microstructure effects on dynamic materials response call for in situ, temporally and spatially resolved, x-ray-based diagnostics. Third-generation synchrotron x-ray sources are advantageous for x-ray phase contrast imaging (PCI) and diffraction under dynamic loading, due to their high photon fluxes, high coherency, and high pulse repetition rates. The feasibility of bulk-scale gas gun shock experiments with dynamic x-ray PCI and diffraction measurements was investigated at the beamline 32ID-B of the Advanced Photon Source. The x-ray beam characteristics, experimental setup, x-ray diagnostics, and static and dynamic test results are described. We demonstrate ultrafast, multiframe, single-pulse PCI measurements with unprecedented temporal (<100 ps) and spatial (˜2 μm) resolutions for bulk-scale shock experiments, as well as single-pulse dynamic Laue diffraction. The results not only substantiate the potential of synchrotron-based experiments for addressing a variety of shock physics problems, but also allow us to identify the technical challenges related to image detection, x-ray source, and dynamic loading.

Design considerations for highly effective fluorescence excitation and detection optical systems for molecular diagnostics

NASA Astrophysics Data System (ADS)

Kasper, Axel; Van Hille, Herbert; Kuk, Sola

2018-02-01

Modern instruments for molecular diagnostics are continuously optimized for diagnostic accuracy, versatility and throughput. The latest progress in LED technology together with tailored optics solutions allows developing highly efficient photonics engines perfectly adapted to the sample under test. Super-bright chip-on-board LED light sources are a key component for such instruments providing maximum luminous intensities in a multitude of narrow spectral bands. In particular the combination of white LEDs with other narrow band LEDs allows achieving optimum efficiency outperforming traditional Xenon light sources in terms of energy consumption, heat dissipation in the system, and switching time between spectral channels. Maximum sensitivity of the diagnostic system can only be achieved with an optimized optics system for the illumination and imaging of the sample. The illumination beam path must be designed for optimum homogeneity across the field while precisely limiting the angular distribution of the excitation light. This is a necessity for avoiding spill-over to the detection beam path and guaranteeing the efficiency of the spectral filtering. The imaging optics must combine high spatial resolution, high light collection efficiency and optimized suppression of excitation light for good signal-to-noise ratio. In order to achieve minimum cross-talk between individual wells in the sample, the optics design must also consider the generation of stray light and the formation of ghost images. We discuss what parameters and limitations have to be considered in an integrated system design approach covering the full path from the light source to the detector.

Diagnostics for a 1.2 kA, 1 MeV, electron induction injector

NASA Astrophysics Data System (ADS)

Houck, T. L.; Anderson, D. E.; Eylon, S.; Henestroza, E.; Lidia, S. M.; Vanecek, D. L.; Westenskow, G. A.; Yu, S. S.

1998-12-01

We are constructing a 1.2 kA, 1 MeV, electron induction injector as part of the RTA program, a collaborative effort between LLNL and LBNL to develop relativistic klystrons for Two-Beam Accelerator applications. The RTA injector will also be used in the development of a high-gradient, low-emittance, electron source and beam diagnostics for the second axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility. The electron source will be a 3.5″-diameter, thermionic, flat-surface, m-type cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150 ns flat top (1% energy variation), and a normalized edge emittance of less than 200 π-mm-mr. Precise measurement of the beam parameters is required so that performance of the RTA injector can be confidently scaled to the 4 kA, 3 MeV, and 2-microsecond pulse parameters of the DARHT injector. Planned diagnostics include an isolated cathode with resistive divider for direct measurement of current emission, resistive wall and magnetic probe current monitors for measuring beam current and centroid position, capacitive probes for measuring A-K gap voltage, an energy spectrometer, and a pepperpot emittance diagnostic. Details of the injector, beam line, and diagnostics are presented.

An informatics model for guiding assembly of telemicrobiology workstations for malaria collaborative diagnostics using commodity products and open-source software.

PubMed

Suhanic, West; Crandall, Ian; Pennefather, Peter

2009-07-17

Deficits in clinical microbiology infrastructure exacerbate global infectious disease burdens. This paper examines how commodity computation, communication, and measurement products combined with open-source analysis and communication applications can be incorporated into laboratory medicine microbiology protocols. Those commodity components are all now sourceable globally. An informatics model is presented for guiding the use of low-cost commodity components and free software in the assembly of clinically useful and usable telemicrobiology workstations. The model incorporates two general principles: 1) collaborative diagnostics, where free and open communication and networking applications are used to link distributed collaborators for reciprocal assistance in organizing and interpreting digital diagnostic data; and 2) commodity engineering, which leverages globally available consumer electronics and open-source informatics applications, to build generic open systems that measure needed information in ways substantially equivalent to more complex proprietary systems. Routine microscopic examination of Giemsa and fluorescently stained blood smears for diagnosing malaria is used as an example to validate the model. The model is used as a constraint-based guide for the design, assembly, and testing of a functioning, open, and commoditized telemicroscopy system that supports distributed acquisition, exploration, analysis, interpretation, and reporting of digital microscopy images of stained malarial blood smears while also supporting remote diagnostic tracking, quality assessment and diagnostic process development. The open telemicroscopy workstation design and use-process described here can address clinical microbiology infrastructure deficits in an economically sound and sustainable manner. It can boost capacity to deal with comprehensive measurement of disease and care outcomes in individuals and groups in a distributed and collaborative fashion. The workstation enables local control over the creation and use of diagnostic data, while allowing for remote collaborative support of diagnostic data interpretation and tracking. It can enable global pooling of malaria disease information and the development of open, participatory, and adaptable laboratory medicine practices. The informatic model highlights how the larger issue of access to generic commoditized measurement, information processing, and communication technology in both high- and low-income countries can enable diagnostic services that are much less expensive, but substantially equivalent to those currently in use in high-income countries.

Cell electrophoresis for diagnostic purposes. II. Critical evaluation of conventional cytopherometry.

PubMed Central

Hoffmann, W.; Kaufmann, R.; Steiner, R.; Werner, W.

1981-01-01

Determination of the electrophoretic mobility of test cells has been widely used in an attempt to detect so-called lymphokines in a laboratory test for cancer, but operational difficulties are inherent in conventional cytopherometers. This study therefore investigates the technical and operational aspects of cell electrophoresis, using the Zeiss cytopherometer; e.g. influence of electro-osmosis, focus uncertainty, movement due to convection and other sources of error. Implications and possible improvements in the test are discussed. PMID:7248145

Endometrial biomarkers for the non-invasive diagnosis of endometriosis.

PubMed

Gupta, Devashana; Hull, M Louise; Fraser, Ian; Miller, Laura; Bossuyt, Patrick M M; Johnson, Neil; Nisenblat, Vicki

2016-04-20

About 10% of reproductive-aged women suffer from endometriosis, which is a costly, chronic disease that causes pelvic pain and subfertility. Laparoscopy is the gold standard diagnostic test for endometriosis, but it is expensive and carries surgical risks. Currently, there are no non-invasive tests available in clinical practice that accurately diagnose endometriosis. This is the first diagnostic test accuracy review of endometrial biomarkers for endometriosis that utilises Cochrane methodologies, providing an update on the rapidly expanding literature in this field. To determine the diagnostic accuracy of the endometrial biomarkers for pelvic endometriosis, using a surgical diagnosis as the reference standard. We evaluated the tests as replacement tests for diagnostic surgery and as triage tests to inform decisions to undertake surgery for endometriosis. We did not restrict the searches to particular study designs, language or publication dates. To identify trials, we searched the following databases: CENTRAL (2015, July), MEDLINE (inception to May 2015), EMBASE (inception to May 2015), CINAHL (inception to April 2015), PsycINFO (inception to April 2015), Web of Science (inception to April 2015), LILACS (inception to April 2015), OAIster (inception to April 2015), TRIP (inception to April 2015) and ClinicalTrials.gov (inception to April 2015). We searched DARE and PubMed databases up to April 2015 to identify reviews and guidelines as sources of references to potentially relevant studies. We also performed searches for papers recently published and not yet indexed in the major databases. The search strategies incorporated words in the title, abstract, text words across the record and the medical subject headings (MeSH). We considered published peer-reviewed, randomised controlled or cross-sectional studies of any size that included prospectively collected samples from any population of reproductive-aged women suspected of having one or more of the following target conditions: ovarian, peritoneal or deep infiltrating endometriosis (DIE). Two authors independently extracted data from each study and performed a quality assessment. For each endometrial diagnostic test, we classified the data as positive or negative for the surgical detection of endometriosis and calculated the estimates of sensitivity and specificity. We considered two or more tests evaluated in the same cohort as separate data sets. We used the bivariate model to obtain pooled estimates of sensitivity and specificity whenever sufficient data were available. The predetermined criteria for a clinically useful test to replace diagnostic surgery was one with a sensitivity of 94% and a specificity of 79%. The criteria for triage tests were set at sensitivity at or above 95% and specificity at or above 50%, which in case of negative results rules out the diagnosis (SnOUT test) or sensitivity at or above 50% with specificity at or above 95%, which in case of positive result rules in the diagnosis (SpIN test). We included 54 studies involving 2729 participants, most of which were of poor methodological quality. The studies evaluated endometrial biomarkers either in specific phases of the menstrual cycle or outside of it, and the studies tested the biomarkers either in menstrual fluid, in whole endometrial tissue or in separate endometrial components. Twenty-seven studies evaluated the diagnostic performance of 22 endometrial biomarkers for endometriosis. These were angiogenesis and growth factors (PROK-1), cell-adhesion molecules (integrins α3β1, α4β1, β1 and α6), DNA-repair molecules (hTERT), endometrial and mitochondrial proteome, hormonal markers (CYP19, 17βHSD2, ER-α, ER-β), inflammatory markers (IL-1R2), myogenic markers (caldesmon, CALD-1), neural markers (PGP 9.5, VIP, CGRP, SP, NPY, NF) and tumour markers (CA-125). Most of these biomarkers were assessed in single studies, whilst only data for PGP 9.5 and CYP19 were available for meta-analysis. These two biomarkers demonstrated significant diversity for the diagnostic estimates between the studies; however, the data were too limited to reliably determine the sources of heterogeneity. The mean sensitivities and specificities of PGP 9.5 (7 studies, 361 women) were 0.96 (95% confidence interval (CI) 0.91 to 1.00) and 0.86 (95% CI 0.70 to 1.00), after excluding one outlier study, and for CYP19 (8 studies, 444 women), they were were 0.77 (95% CI 0.70 to 0.85) and 0.74 (95% CI 0.65 to 84), respectively. We could not statistically evaluate other biomarkers in a meaningful way. An additional 31 studies evaluated 77 biomarkers that showed no evidence of differences in expression levels between the groups of women with and without endometriosis. We could not statistically evaluate most of the biomarkers assessed in this review in a meaningful way. In view of the low quality of most of the included studies, the findings of this review should be interpreted with caution. Although PGP 9.5 met the criteria for a replacement test, it demonstrated considerable inter study heterogeneity in diagnostic estimates, the source of which could not be determined. Several endometrial biomarkers, such as endometrial proteome, 17βHSD2, IL-1R2, caldesmon and other neural markers (VIP, CGRP, SP, NPY and combination of VIP, PGP 9.5 and SP) showed promising evidence of diagnostic accuracy, but there was insufficient or poor quality evidence for any clinical recommendations. Laparoscopy remains the gold standard for the diagnosis of endometriosis, and using any non-invasive tests should only be undertaken in a research setting. We have also identified a number of biomarkers that demonstrated no diagnostic value for endometriosis. We recommend that researchers direct future studies towards biomarkers with high diagnostic potential in good quality diagnostic studies.

A suite of diagnostics to validate and optimize the prototype ITER neutral beam injector

NASA Astrophysics Data System (ADS)

Pasqualotto, R.; Agostini, M.; Barbisan, M.; Brombin, M.; Cavazzana, R.; Croci, G.; Dalla Palma, M.; Delogu, R. S.; De Muri, M.; Muraro, A.; Peruzzo, S.; Pimazzoni, A.; Pomaro, N.; Rebai, M.; Rizzolo, A.; Sartori, E.; Serianni, G.; Spagnolo, S.; Spolaore, M.; Tardocchi, M.; Zaniol, B.; Zaupa, M.

2017-10-01

The ITER project requires additional heating provided by two neutral beam injectors using 40 A negative deuterium ions accelerated at 1 MV. As the beam requirements have never been experimentally met, a test facility is under construction at Consorzio RFX, which hosts two experiments: SPIDER, full-size 100 kV ion source prototype, and MITICA, 1 MeV full-size ITER injector prototype. Since diagnostics in ITER injectors will be mainly limited to thermocouples, due to neutron and gamma radiation and to limited access, it is crucial to thoroughly investigate and characterize in more accessible experiments the key parameters of source plasma and beam, using several complementary diagnostics assisted by modelling. In SPIDER and MITICA the ion source parameters will be measured by optical emission spectroscopy, electrostatic probes, cavity ring down spectroscopy for H^- density and laser absorption spectroscopy for cesium density. Measurements over multiple lines-of-sight will provide the spatial distribution of the parameters over the source extension. The beam profile uniformity and its divergence are studied with beam emission spectroscopy, complemented by visible tomography and neutron imaging, which are novel techniques, while an instrumented calorimeter based on custom unidirectional carbon fiber composite tiles observed by infrared cameras will measure the beam footprint on short pulses with the highest spatial resolution. All heated components will be monitored with thermocouples: as these will likely be the only measurements available in ITER injectors, their capabilities will be investigated by comparison with other techniques. SPIDER and MITICA diagnostics are described in the present paper with a focus on their rationale, key solutions and most original and effective implementations.

Using routine diagnostic data as a method of surveillance of arboviral infection in travellers: a comparative analysis with a focus on dengue.

PubMed

Cleton, Natalie; Reusken, Chantal; Murk, Jean-Luc; de Jong, Menno; Reimerink, Johan; van der Eijk, Annemiek; Koopmans, Marion

2014-01-01

In a large part of the developing world, limited infectious disease surveillance is performed. In laboratory information management systems data on diagnostic requests is available and may be amenable to trend analyses. We explored this potential, using DENV diagnostic requests as a model. Test results and anonymised information provided by clinicians were received for 8942 patients from diagnostic centres in the Netherlands from January 2000 to May 2011. The data were evaluated for completeness of a predefined minimal dataset and trends in DENV positive results by travel destination. Population travel data were obtained from a commercial registry, and dengue case notification data by country from WHO DengueNet. Vaccination history was rarely reported (0.4%); travel destination was completed for 42% of requests; trends in diagnostic requests and IgM positive tests for this subset correlated to the WHO DENV notifications for the three main travel destinations, with some discrepancies. Additionally, this approach may provide information on disease outbreaks with other pathogens causing diseases clinically similar to DENV. PCR data proved to be insufficient for trend monitoring by country. This approach is not straightforward, but shows potential for use as a source of additional information for surveillance of disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

A motion detection system for AXAF X-ray ground testing

NASA Technical Reports Server (NTRS)

Arenberg, Jonathan W.; Texter, Scott C.

1993-01-01

The concept, implementation, and performance of the motion detection system (MDS) designed as a diagnostic for X-ray ground testing for AXAF are described. The purpose of the MDS is to measure the magnitude of a relative rigid body motion among the AXAF test optic, the X-ray source, and X-ray focal plane detector. The MDS consists of a point source, lens, centroid detector, transimpedance amplifier, and computer system. Measurement of the centroid position of the image of the optical point source provides a direct measure of the motions of the X-ray optical system. The outputs from the detector and filter/amplifier are digitized and processed using the calibration with a 50 Hz bandwidth to give the centroid's location on the detector. Resolution of 0.008 arcsec has been achieved by this system. Data illustrating the performance of the motion detection system are also presented.

External Quality Assessment beyond the analytical phase: an Australian perspective.

PubMed

Badrick, Tony; Gay, Stephanie; McCaughey, Euan J; Georgiou, Andrew

2017-02-15

External Quality Assessment (EQA) is the verification, on a recurring basis, that laboratory results conform to expectations for the quality required for patient care. It is now widely recognised that both the pre- and post-laboratory phase of testing, termed the diagnostic phases, are a significant source of laboratory errors. These errors have a direct impact on both the effectiveness of the laboratory and patient safety. Despite this, Australian laboratories tend to be focussed on very narrow concepts of EQA, primarily surrounding test accuracy, with little in the way of EQA programs for the diagnostic phases. There is a wide range of possibilities for the development of EQA for the diagnostic phases in Australia, such as the utilisation of scenarios and health informatics. Such programs can also be supported through advances in health information and communications technology, including electronic test ordering and clinical decision support systems. While the development of such programs will require consultation and support from the referring doctors, and their format will need careful construction to ensure that the data collected is de-identified and provides education as well as useful and informative data, we believe that there is high value in the development of such programs. Therefore, it is our opinion that all pathology laboratories should strive to be involved in an EQA program in the diagnostic phases to both monitor the diagnostic process and to identify, learn from and reduce errors and near misses in these phases in a timely fashion.

External Quality Assessment beyond the analytical phase: an Australian perspective

PubMed Central

Gay, Stephanie; McCaughey, Euan J.; Georgiou, Andrew

2017-01-01

External Quality Assessment (EQA) is the verification, on a recurring basis, that laboratory results conform to expectations for the quality required for patient care. It is now widely recognised that both the pre- and post-laboratory phase of testing, termed the diagnostic phases, are a significant source of laboratory errors. These errors have a direct impact on both the effectiveness of the laboratory and patient safety. Despite this, Australian laboratories tend to be focussed on very narrow concepts of EQA, primarily surrounding test accuracy, with little in the way of EQA programs for the diagnostic phases. There is a wide range of possibilities for the development of EQA for the diagnostic phases in Australia, such as the utilisation of scenarios and health informatics. Such programs can also be supported through advances in health information and communications technology, including electronic test ordering and clinical decision support systems. While the development of such programs will require consultation and support from the referring doctors, and their format will need careful construction to ensure that the data collected is de-identified and provides education as well as useful and informative data, we believe that there is high value in the development of such programs. Therefore, it is our opinion that all pathology laboratories should strive to be involved in an EQA program in the diagnostic phases to both monitor the diagnostic process and to identify, learn from and reduce errors and near misses in these phases in a timely fashion. PMID:28392728

Study of a high power hydrogen beam diagnostic based on secondary electron emission.

PubMed

Sartori, E; Panasenkov, A; Veltri, P; Serianni, G; Pasqualotto, R

2016-11-01

In high power neutral beams for fusion, beam uniformity is an important figure of merit. Knowing the transverse power profile is essential during the initial phases of beam source operation, such as those expected for the ITER heating neutral beam (HNB) test facility. To measure it a diagnostic technique is proposed, based on the collection of secondary electrons generated by beam-surface and beam-gas interactions, by an array of positively biased collectors placed behind the calorimeter tubes. This measurement showed in the IREK test stand good proportionality to the primary beam current. To investigate the diagnostic performances in different conditions, we developed a numerical model of secondary electron emission, induced by beam particle impact on the copper tubes, and reproducing the cascade of secondary emission caused by successive electron impacts. The model is first validated against IREK measurements. It is then applied to the HNB case, to assess the locality of the measurement, the proportionality to the beam current density, and the influence of beam plasma.

GEM detectors development for radiation environment: neutron tests and simulations

NASA Astrophysics Data System (ADS)

Chernyshova, Maryna; Jednoróg, Sławomir; Malinowski, Karol; Czarski, Tomasz; Ziółkowski, Adam; Bieńkowska, Barbara; Prokopowicz, Rafał; Łaszyńska, Ewa; Kowalska-Strzeciwilk, Ewa; Poźniak, Krzysztof T.; Kasprowicz, Grzegorz; Zabołotny, Wojciech; Wojeński, Andrzej; Krawczyk, Rafał D.; Linczuk, Paweł; Potrykus, Paweł; Bajdel, Barcel

2016-09-01

One of the requests from the ongoing ITER-Like Wall Project is to have diagnostics for Soft X-Ray (SXR) monitoring in tokamak. Such diagnostics should be focused on tungsten emission measurements, as an increased attention is currently paid to tungsten due to a fact that it became a main candidate for the plasma facing material in ITER and future fusion reactor. In addition, such diagnostics should be able to withstand harsh radiation environment at tokamak during its operation. The presented work is related to the development of such diagnostics based on Gas Electron Multiplier (GEM) technology. More specifically, an influence of neutron radiation on performance of the GEM detectors is studied both experimentally and through computer simulations. The neutron induced radioactivity (after neutron source exposure) was found to be not pronounced comparing to an impact of other secondary neutron reaction products (during the exposure).

Modeling and simulation of a beam emission spectroscopy diagnostic for the ITER prototype neutral beam injector.

PubMed

Barbisan, M; Zaniol, B; Pasqualotto, R

2014-11-01

A test facility for the development of the neutral beam injection system for ITER is under construction at Consorzio RFX. It will host two experiments: SPIDER, a 100 keV H(-)/D(-) ion RF source, and MITICA, a prototype of the full performance ITER injector (1 MV, 17 MW beam). A set of diagnostics will monitor the operation and allow to optimize the performance of the two prototypes. In particular, beam emission spectroscopy will measure the uniformity and the divergence of the fast particles beam exiting the ion source and travelling through the beam line components. This type of measurement is based on the collection of the Hα/Dα emission resulting from the interaction of the energetic particles with the background gas. A numerical model has been developed to simulate the spectrum of the collected emissions in order to design this diagnostic and to study its performance. The paper describes the model at the base of the simulations and presents the modeled Hα spectra in the case of MITICA experiment.

Real-time neutron imaging of gas turbines

NASA Astrophysics Data System (ADS)

Stewart, P. A. E.

1987-06-01

The current status of real-time neutron radiography imaging is briefly reviewed, and results of tests carried out on cold neutron sources are reported. In particular, attention is given to demonstrations of neutron radiography on a running gas turbine engine. The future role of real-time neutron imaging in engineering diagnostics is briefly discussed.

Beam-Plasma Interaction Experiments on the Princeton Advanced Test Stand

NASA Astrophysics Data System (ADS)

Stepanov, A.; Gilson, E. P.; Grisham, L.; Kaganovich, I. D.; Davidson, R. C.

2011-10-01

The Princeton Advanced Test Stand (PATS) is a compact experimental facility for studying the fundamental physics of intense beam-plasma interactions relevant to the Neutralized Drift Compression Experiment - II (NDCX-II). The PATS facility consists of a 100 keV ion beam source mounted on a six-foot-long vacuum chamber with numerous ports for diagnostic access. A 100 keV Ar+ beam is launched into a volumetric plasma, which is produced by a ferroelectric plasma source (FEPS). Beam diagnostics upstream and downstream of the FEPS allow for detailed studies of the effects that the plasma has on the beam. This setup is designed for studying the dependence of charge and current neutralization and beam emittance growth on the beam and plasma parameters. This work reports initial measurements of beam quality produced by the extraction electrodes that were recently installed on the PATS device. The transverse beam phase space is measured with double-slit emittance scanners, and the experimental results are compared to WARP simulations of the extraction system. This research is supported by the U.S. Department of Energy.

Experimental characterization of hollow-cathode plasma sources at Frascati

NASA Technical Reports Server (NTRS)

Vannaroni, G.; Cosmovici, C. B.; Bonifazi, C.; Mccoy, J.

1988-01-01

An experimental characterization has been conducted for hollow cathodes applicable as plasma contactors on Space Shuttle-based experiments. The diagnostics tests were conducted in an 0.5 cu m vacuum chamber by means of Langmuir probes at various distances from the source. Two electron populations are noted, one in the 0.3-1 eV and the other in the 7-11 eV temperature range. Current developments in the design of plasma chambers incorporating magnetic field compensation are noted.

Collaborative Research: Atmospheric Pressure Microplasma Chemistry-Photon Synergies Final Report

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

Graves, David

Combining the effects of low temperature, atmospheric pressure microplasmas and microplasma photon sources shows greatly expanded range of applications of each of them. The plasma sources create active chemical species and these can be activated further by addition of photons and associated photochemistry. There are many ways to combine the effects of plasma chemistry and photochemistry, especially if there are multiple phases present. The project combines construction of appropriate test experimental systems, various spectroscopic diagnostics and mathematical modeling.

Investigation of plasma parameters at BATMAN for variation of the Cs evaporation asymmetry and comparing two driver geometries

NASA Astrophysics Data System (ADS)

Wimmer, C.; Fantz, U.; Aza, E.; Jovović, J.; Kraus, W.; Mimo, A.; Schiesko, L.

2017-08-01

The Neutral Beam Injection (NBI) system for fusion devices like ITER and, beyond ITER, DEMO requires large scale sources for negative hydrogen ions. BATMAN (Bavarian Test Machine for Negative ions) is a test facility attached with the prototype source for the ITER NBI (1/8 source size of the ITER source), dedicated to physical investigations due to its flexible access for diagnostics and exchange of source components. The required amount of negative ions is produced by surface conversion of hydrogen atoms or ions on caesiated surfaces. Several diagnostic tools (Optical Emission Spectroscopy, Cavity Ring-Down Spectroscopy for H-, Langmuir probes, Tunable Diode Laser Absorption Spectroscopy for Cs) allow the determination of plasma parameters in the ion source. Plasma parameters for two modifications of the standard prototype source have been investigated: Firstly, a second Cs oven has been installed in the bottom part of the back plate in addition to the regularly used oven in the top part of the back plate. Evaporation from the top oven only can lead to a vertically asymmetric Cs distribution in front of the plasma grid. Using both ovens, a symmetric Cs distribution can be reached - however, in most cases no significant change of the extracted ion current has been determined for varying Cs symmetry if the source is well-conditioned. Secondly, BATMAN has been equipped with a much larger, racetrack-shaped RF driver (area of 32×58 cm2) instead of the cylindrical RF driver (diameter of 24.5 cm). The main idea is that one racetrack driver could substitute two cylindrical drivers in larger sources with increased reliability and power efficiency. For the same applied RF power, the electron density is lower in the racetrack driver due to its five times higher volume. The fraction of hydrogen atoms to molecules, however, is at a similar level or even slightly higher, which is a promising result for application in larger sources.

Sample size in studies on diagnostic accuracy in ophthalmology: a literature survey.

PubMed

Bochmann, Frank; Johnson, Zoe; Azuara-Blanco, Augusto

2007-07-01

To assess the sample sizes used in studies on diagnostic accuracy in ophthalmology. Design and sources: A survey literature published in 2005. The frequency of reporting calculations of sample sizes and the samples' sizes were extracted from the published literature. A manual search of five leading clinical journals in ophthalmology with the highest impact (Investigative Ophthalmology and Visual Science, Ophthalmology, Archives of Ophthalmology, American Journal of Ophthalmology and British Journal of Ophthalmology) was conducted by two independent investigators. A total of 1698 articles were identified, of which 40 studies were on diagnostic accuracy. One study reported that sample size was calculated before initiating the study. Another study reported consideration of sample size without calculation. The mean (SD) sample size of all diagnostic studies was 172.6 (218.9). The median prevalence of the target condition was 50.5%. Only a few studies consider sample size in their methods. Inadequate sample sizes in diagnostic accuracy studies may result in misleading estimates of test accuracy. An improvement over the current standards on the design and reporting of diagnostic studies is warranted.

In Silico identification of pathogenic strains of Cronobacter from Biochemical data reveals association of inositol fermentation with pathogenicity.

PubMed

Hamby, Stephen E; Joseph, Susan; Forsythe, Stephen J; Chuzhanova, Nadia

2011-09-20

Cronobacter, formerly known as Enterobacter sakazakii, is a food-borne pathogen known to cause neonatal meningitis, septicaemia and death. Current diagnostic tests for identification of Cronobacter do not differentiate between species, necessitating time consuming 16S rDNA gene sequencing or multilocus sequence typing (MLST). The organism is ubiquitous, being found in the environment and in a wide range of foods, although there is variation in pathogenicity between Cronobacter isolates and between species. Therefore to be able to differentiate between the pathogenic and non-pathogenic strains is of interest to the food industry and regulators. Here we report the use of Expectation Maximization clustering to categorise 98 strains of Cronobacter as pathogenic or non-pathogenic based on biochemical test results from standard diagnostic test kits. Pathogenicity of a strain was postulated on the basis of either pathogenic symptoms associated with strain source or corresponding MLST sequence types, allowing the clusters to be labelled as containing either pathogenic or non-pathogenic strains. The resulting clusters gave good differentiation of strains into pathogenic and non-pathogenic groups, corresponding well to isolate source and MLST sequence type. The results also revealed a potential association between pathogenicity and inositol fermentation. An investigation of the genomes of Cronobacter sakazakii and C. turicensis revealed the gene for inositol monophosphatase is associated with putative virulence factors in pathogenic strains of Cronobacter. We demonstrated a computational approach allowing existing diagnostic kits to be used to identify pathogenic strains of Cronobacter. The resulting clusters correlated well with MLST sequence types and revealed new information about the pathogenicity of Cronobacter species.

A neutron diagnostic for high current deuterium beams.

PubMed

Rebai, M; Cavenago, M; Croci, G; Dalla Palma, M; Gervasini, G; Ghezzi, F; Grosso, G; Murtas, F; Pasqualotto, R; Cippo, E Perelli; Tardocchi, M; Tollin, M; Gorini, G

2012-02-01

A neutron diagnostic for high current deuterium beams is proposed for installation on the spectral shear interferometry for direct electric field reconstruction (SPIDER, Source for Production of Ion of Deuterium Extracted from RF plasma) test beam facility. The proposed detection system is called Close-contact Neutron Emission Surface Mapping (CNESM). The diagnostic aims at providing the map of the neutron emission on the beam dump surface by placing a detector in close contact, right behind the dump. CNESM uses gas electron multiplier detectors equipped with a cathode that also serves as neutron-proton converter foil. The cathode is made of a thin polythene film and an aluminium film; it is designed for detection of neutrons of energy >2.2 MeV with an incidence angle < 45°. CNESM was designed on the basis of simulations of the different steps from the deuteron beam interaction with the beam dump to the neutron detection in the nGEM. Neutron scattering was simulated with the MCNPX code. CNESM on SPIDER is a first step towards the application of this diagnostic technique to the MITICA beam test facility, where it will be used to resolve the horizontal profile of the beam intensity.

A neutron diagnostic for high current deuterium beams

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

Rebai, M.; Perelli Cippo, E.; Cavenago, M.

2012-02-15

A neutron diagnostic for high current deuterium beams is proposed for installation on the spectral shear interferometry for direct electric field reconstruction (SPIDER, Source for Production of Ion of Deuterium Extracted from RF plasma) test beam facility. The proposed detection system is called Close-contact Neutron Emission Surface Mapping (CNESM). The diagnostic aims at providing the map of the neutron emission on the beam dump surface by placing a detector in close contact, right behind the dump. CNESM uses gas electron multiplier detectors equipped with a cathode that also serves as neutron-proton converter foil. The cathode is made of a thinmore » polythene film and an aluminium film; it is designed for detection of neutrons of energy >2.2 MeV with an incidence angle < 45 deg. CNESM was designed on the basis of simulations of the different steps from the deuteron beam interaction with the beam dump to the neutron detection in the nGEM. Neutron scattering was simulated with the MCNPX code. CNESM on SPIDER is a first step towards the application of this diagnostic technique to the MITICA beam test facility, where it will be used to resolve the horizontal profile of the beam intensity.« less

A minority perspective in the diagnosis of child language disorders.

PubMed

Seymour, H N; Bland, L

1991-01-01

The effective diagnosis and treatment of persons from diverse minority language backgrounds has become an important issue in the field of speech and language pathology. Yet, many SLPs have had little or no formal training in minority language, there is a paucity of normative data on language acquisition in minority groups, and there are few standardized speech and language tests appropriate for these groups. We described a diagnostic process that addresses these problems. The diagnostic protocol we have proposed for a child from a Black English-speaking background characterizes many of the major issues in treating minority children. In summary, we proposed four assessment strategies: gathering referral source data; making direct observations; using standardized tests of non-speech and language behavior (cognition, perception, motor, etc.); and eliciting language samples and probes.

Status of the Negative Ion Based Heating and Diagnostic Neutral Beams for ITER

NASA Astrophysics Data System (ADS)

Schunke, B.; Bora, D.; Hemsworth, R.; Tanga, A.

2009-03-01

The current baseline of ITER foresees 2 Heating Neutral Beam (HNB's) systems based on negative ion technology, each accelerating to 1 MeV 40 A of D- and capable of delivering 16.5 MW of D0 to the ITER plasma, with a 3rd HNB injector foreseen as an upgrade option [1]. In addition a dedicated Diagnostic Neutral Beam (DNB) accelerating 60 A of H- to 100 keV will inject ≈15 A equivalent of H0 for charge exchange recombination spectroscopy and other diagnostics. Recently the RF driven negative ion source developed by IPP Garching has replaced the filamented ion source as the reference ITER design. The RF source developed at IPP, which is approximately a quarter scale of the source needed for ITER, is expected to have reduced caesium consumption compared to the filamented arc driven ion source. The RF driven source has demonstrated adequate accelerated D- and H- current densities as well as long-pulse operation [2, 3]. It is foreseen that the HNB's and the DNB will use the same negative ion source. Experiments with a half ITER-size ion source are on-going at IPP and the operation of a full-scale ion source will be demonstrated, at full power and pulse length, in the dedicated Ion Source Test Bed (ISTF), which will be part of the Neutral Beam Test Facility (NBTF), in Padua, Italy. This facility will carry out the necessary R&D for the HNB's for ITER and demonstrate operation of the full-scale HNB beamline. An overview of the current status of the neutral beam (NB) systems and the chosen configuration will be given and the ongoing integration effort into the ITER plant will be highlighted. It will be demonstrated how installation and maintenance logistics have influenced the design, notably the top access scheme facilitating access for maintenance and installation. The impact of the ITER Design Review and recent design change requests (DCRs) will be briefly discussed, including start-up and commissioning issues. The low current hydrogen phase now envisaged for start-up imposed specific requirements for operating the HNB's at full beam power. It has been decided to address the shinethrough issue by installing wall armour protection, which increases the operational space in all scenarios. Other NB related issues identified by the Design Review process will be discussed and the possible changes to the ITER baseline indicated.

Review: Diagnostic accuracy of PCR-based detection tests for Helicobacter Pylori in stool samples.

PubMed

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.

Declic: design, integration and testing of a multi configurable instrument using optical diagnostics to study directional solidification and critical fluids

NASA Astrophysics Data System (ADS)

Durieux, A.; Martin, B.; Laubier, D.

2017-11-01

DECLIC, a Facility dedicated to the study of transparent media under microgravity, will be used in an ISS EXPRESS Rack. This paper focuses on the EXL which contains two optical boxes disposed on two opposite sides of the cavity where the Inserts to be studied shall be locked. At the moment, three types of inserts are planned to be accommodated in the EXL. Various optical diagnostics are available by configuring the EXL (sources, sensors, mechanisms). After the presentation of the EXL design, this article deals with some manufacturing and testing aspects, such as the use of COTS (cameras). Specific OGSE have been developed in order to simulate the optical interfaces and the propagation of beams in the inserts. Three models of the EXL have been integrated and fully tested, including the Flight Model. The sequence of tests, the performances measured, and then some images of the experiments performed with the inserts will be presented.

Accidental mydriasis from blue nightshade "lipstick".

PubMed

Rubinfeld, R S; Currie, J N

1987-03-01

A 7-year-old girl presented with bilaterally dilated pupils, nausea, and vomiting 2 days after head trauma. Pilocarpine pupil testing led to the correct diagnosis of pharmacologic pupillary dilation from an unexpected and unusual source of plant poisoning, Solanum dulcamara (blue nightshade). In patients with internal ophthalmoplegia, awareness of the possibility of pharmacologic mydriasis and correct use of topical pilocarpine testing can preclude the necessity for neuroradiologic and invasive diagnostic studies, even in cases with atypical or complex presentations.

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

Maestas, J.H.

The Loopback Tester is an Intel SBC 86/12A Single Board Computer and an Intel SBC 534 Communications Expansion Board configured and programmed to perform various basic or less. These tests include: (1) Data Communications Equipment (DCE) transmit timing detection (2) data rate measurement (3) instantaneous loopback indication and (4) bit error rate testing. It requires no initial setup after plug in, and can be used to locate the source of communications loss in a circuit. It can also be used to determine when crypto variable mismatch problems are the source of communications loss. This report discusses the functionality of themore » Loopback Tester as a diagnostic device. It also discusses the hardware and software which implements this simple yet reliable device.« less

Legionnaire's Disease Since Philadelphia: Lessons Learned and Continued Progress.

PubMed

Cunha, Cheston B; Cunha, Burke A

2017-03-01

Legionnaire's disease has been recognized as a cause of severe community-acquired pneumonia (CAP). Legionnaire's disease has characteristic extrapulmonary findings that are the basis for a presumptive clinical diagnosis. The widespread use of Legionella culture, sputum DFA, serology, urinary antigen testing, and polymerase chain reaction have allowed earlier diagnosis of Legionnaire's disease. Excluding common source outbreaks, CAP caused by Legionnaire's disease is manifested as sporadic cases. In contrast, nosocomial Legionnaire's disease occurs in clusters or outbreaks from common Legionella species-contaminated water sources. Improved diagnostic tests have permitted accurate diagnosis. Bacterial coinfections with Legionnaire's disease are uncommon, but when present, are most often associated with bacteremia pneumococcal pneumonia. Copyright © 2016 Elsevier Inc. All rights reserved.

Production of recombinant dengue non-structural 1 (NS1) proteins from clinical virus isolates.

PubMed

Yohan, Benediktus; Wardhani, Puspa; Aryati; Trimarsanto, Hidayat; Sasmono, R Tedjo

2017-01-01

Dengue is a febrile disease caused by infection of dengue virus (DENV). Early diagnosis of dengue infection is important for better management of the disease. The DENV Non-Structural Protein 1 (NS1) antigen has been routinely used for the early dengue detection. In dengue epidemic countries such as Indonesia, clinicians are increasingly relying on the NS1 detection for confirmation of dengue infection. Various NS1 diagnostic tests are commercially available, however different sensitivities and specificities were observed in various settings. This study was aimed to generate dengue NS1 recombinant protein for the development of dengue diagnostic tests. Four Indonesian DENV isolates were used as the source of the NS1 gene cloning, expression, and purification in bacterial expression system. Recombinant NS1 proteins were successfully purified and their antigenicities were assessed. Immunization of mice with recombinant proteins observed the immunogenicity of the NS1 protein. The generated recombinant proteins can be potentially used in the development of NS1 diagnostic test. With minimal modifications, this method can be used for producing NS1 recombinant proteins from isolates obtained from other geographical regions. Copyright © 2016 Elsevier Inc. All rights reserved.

Graph-based real-time fault diagnostics

NASA Technical Reports Server (NTRS)

Padalkar, S.; Karsai, G.; Sztipanovits, J.

1988-01-01

A real-time fault detection and diagnosis capability is absolutely crucial in the design of large-scale space systems. Some of the existing AI-based fault diagnostic techniques like expert systems and qualitative modelling are frequently ill-suited for this purpose. Expert systems are often inadequately structured, difficult to validate and suffer from knowledge acquisition bottlenecks. Qualitative modelling techniques sometimes generate a large number of failure source alternatives, thus hampering speedy diagnosis. In this paper we present a graph-based technique which is well suited for real-time fault diagnosis, structured knowledge representation and acquisition and testing and validation. A Hierarchical Fault Model of the system to be diagnosed is developed. At each level of hierarchy, there exist fault propagation digraphs denoting causal relations between failure modes of subsystems. The edges of such a digraph are weighted with fault propagation time intervals. Efficient and restartable graph algorithms are used for on-line speedy identification of failure source components.

Single element of the matrix source of negative hydrogen ions: Measurements of the extracted currents combined with diagnostics

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

Yordanov, D., E-mail: yordanov@phys.uni-sofia.bg; Lishev, St.; Shivarova, A.

2016-02-15

Combining measurements of the extracted currents with probe and laser-photodetachment diagnostics, the study is an extension of recent tests of factors and gas-discharge conditions stimulating the extraction of volume produced negative ions. The experiment is in a single element of a rf source with the design of a matrix of small-radius inductively driven discharges. The results are for the electron and negative-ion densities, for the plasma potential and for the electronegativity in the vicinity of the plasma electrode as well as for the currents of the extracted negative ions and electrons. The plasma-electrode bias and the rf power have beenmore » varied. Necessity of a high bias to the plasma electrode and stable linear increase of the extracted currents with the rf power are the main conclusions.« less

Molecular allergy diagnostics using IgE singleplex determinations: methodological and practical considerations for use in clinical routine: Part 18 of the Series Molecular Allergology.

PubMed

Kleine-Tebbe, Jörg; Jakob, Thilo

Allergen molecules (synonyms: single allergens, allergen components) open up new horizons for the targeted allergen-specific diagnostics of immunoglobulin E (IgE) in singleplex determination. The following rationales support the targeted use of allergen molecules and, more importantly, improve test properties: (1) increased test sensitivity ("analytical sensitivity"), particularly when important allergens are under-represented or lacking in the extract; (2) improved test selectivity (analytical specificity), particularly when the selected IgE repertoire against an allergen yields additional information on: (a) potential risk, (b) possible cross-reactivity, or (c) primary (species-specific) sensitization. However, the appropriate indication for the use of single allergens can only be established on a case-by-case basis (depending on the clinical context and previous history) and in an allergen-specific manner (depending on the allergen source and the single allergens available), rather than in a standardized way. Numerous investigations on suspected food allergy, insect venom allergy, or sensitization to respiratory allergens have meanwhile demonstrated the successful use of defined molecules for allergen-specific singleplex IgE diagnosis. Specific IgE to single allergens is limited in its suitability to predict the clinical relevance of sensitivity on an individual basis. In food allergies, one can at best identify the relative risk of a clinical reaction on the basis of an IgE profile, but no absolutely reliable prediction on (future) tolerance can be made. Ultimately, the clinical relevance of all IgE findings depends on the presence of corresponding symptoms and can only be assessed on an individual basis (previous history, symptom log, and provocation testing with the relevant allergen source where appropriate). Thus, also in molecular allergology, the treating physician and not the test result should determine the clinical relevance of diagnostic findings. Supplementary material is available for this article at 10.1007/s40629-015-0067-z and is accessible for authorized users.

Neutron monitoring and electrode calorimetry experiments in the HIP-1 Hot Ion Plasma

NASA Technical Reports Server (NTRS)

Reinmann, J. J.; Layman, R. W.

1977-01-01

Results are presented for two diagnostic procedures on HIP-1: neutron diagnostics to determine where neutrons originated within the plasma discharge chamber and electrode calorimetry to measure the steady-state power absorbed by the two anodes and cathodes. Results are also reported for a hot-ion plasma formed with a continuous-cathode rod, one that spans the full length of the test section, in place of the two hollow cathodes. The outboard neutron source strength increased relative to that at the midplane when (1) the cathode tips were moved farther outboard, (2) the anode diameters were increased, and (3) one of the anodes was removed. The distribution of neutron sources within the plasma discharge chamber was insensitive to the division of current between the two cathodes. For the continuous cathode, increasing the discharge current increased the midplane neutron source strength relative to the outboard source strength. Each cathode absorbed from 12 to 15 percent of the input power regardless of the division of current between the cathodes. The anodes absorbed from 20 to 40 percent of the input power. The division of power absorption between the anodes varied with plasma operating conditions and electrode placement.

Status of the Negative Ion Based Heating and Diagnostic Neutral Beams for ITER

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

Schunke, B.; Bora, D.; Hemsworth, R.

2009-03-12

The current baseline of ITER foresees 2 Heating Neutral Beam (HNB's) systems based on negative ion technology, each accelerating to 1 MeV 40 A of D{sup -} and capable of delivering 16.5 MW of D{sup 0} to the ITER plasma, with a 3rd HNB injector foreseen as an upgrade option. In addition a dedicated Diagnostic Neutral Beam (DNB) accelerating 60 A of H{sup -} to 100 keV will inject {approx_equal}15 A equivalent of H{sup 0} for charge exchange recombination spectroscopy and other diagnostics. Recently the RF driven negative ion source developed by IPP Garching has replaced the filamented ion sourcemore » as the reference ITER design. The RF source developed at IPP, which is approximately a quarter scale of the source needed for ITER, is expected to have reduced caesium consumption compared to the filamented arc driven ion source. The RF driven source has demonstrated adequate accelerated D{sup -} and H{sup -} current densities as well as long-pulse operation. It is foreseen that the HNB's and the DNB will use the same negative ion source. Experiments with a half ITER-size ion source are on-going at IPP and the operation of a full-scale ion source will be demonstrated, at full power and pulse length, in the dedicated Ion Source Test Bed (ISTF), which will be part of the Neutral Beam Test Facility (NBTF), in Padua, Italy. This facility will carry out the necessary R and D for the HNB's for ITER and demonstrate operation of the full-scale HNB beamline. An overview of the current status of the neutral beam (NB) systems and the chosen configuration will be given and the ongoing integration effort into the ITER plant will be highlighted. It will be demonstrated how installation and maintenance logistics have influenced the design, notably the top access scheme facilitating access for maintenance and installation. The impact of the ITER Design Review and recent design change requests (DCRs) will be briefly discussed, including start-up and commissioning issues. The low current hydrogen phase now envisaged for start-up imposed specific requirements for operating the HNB's at full beam power. It has been decided to address the shinethrough issue by installing wall armour protection, which increases the operational space in all scenarios. Other NB related issues identified by the Design Review process will be discussed and the possible changes to the ITER baseline indicated.« less

42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Procedural Terminology published by the American Medical Association. (vii) Diagnostic tests performed by a... & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL INSURANCE (SMI) BENEFITS Medical and Other Health Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory...

42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Procedural Terminology published by the American Medical Association. (vii) Diagnostic tests performed by a... & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL INSURANCE (SMI) BENEFITS Medical and Other Health Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory...

A method for the development of disease-specific reference standards vocabularies from textual biomedical literature resources

PubMed Central

Wang, Liqin; Bray, Bruce E.; Shi, Jianlin; Fiol, Guilherme Del; Haug, Peter J.

2017-01-01

Objective Disease-specific vocabularies are fundamental to many knowledge-based intelligent systems and applications like text annotation, cohort selection, disease diagnostic modeling, and therapy recommendation. Reference standards are critical in the development and validation of automated methods for disease-specific vocabularies. The goal of the present study is to design and test a generalizable method for the development of vocabulary reference standards from expert-curated, disease-specific biomedical literature resources. Methods We formed disease-specific corpora from literature resources like textbooks, evidence-based synthesized online sources, clinical practice guidelines, and journal articles. Medical experts annotated and adjudicated disease-specific terms in four classes (i.e., causes or risk factors, signs or symptoms, diagnostic tests or results, and treatment). Annotations were mapped to UMLS concepts. We assessed source variation, the contribution of each source to build disease-specific vocabularies, the saturation of the vocabularies with respect to the number of used sources, and the generalizability of the method with different diseases. Results The study resulted in 2588 string-unique annotations for heart failure in four classes, and 193 and 425 respectively for pulmonary embolism and rheumatoid arthritis in treatment class. Approximately 80% of the annotations were mapped to UMLS concepts. The agreement among heart failure sources ranged between 0.28 and 0.46. The contribution of these sources to the final vocabulary ranged between 18% and 49%. With the sources explored, the heart failure vocabulary reached near saturation in all four classes with the inclusion of minimal six sources (or between four to seven sources if only counting terms occurred in two or more sources). It took fewer sources to reach near saturation for the other two diseases in terms of the treatment class. Conclusions We developed a method for the development of disease-specific reference vocabularies. Expert-curated biomedical literature resources are substantial for acquiring disease-specific medical knowledge. It is feasible to reach near saturation in a disease-specific vocabulary using a relatively small number of literature sources. PMID:26971304

Decision making about healthcare-related tests and diagnostic test strategies. Paper 4: International guidelines show variability in their approaches.

PubMed

Mustafa, Reem A; Wiercioch, Wojtek; Arevalo-Rodriguez, Ingrid; Cheung, Adrienne; Prediger, Barbara; Ivanova, Liudmila; Ventresca, Matthew; Brozek, Jan; Santesso, Nancy; Bossuyt, Patrick; Garg, Amit X; Lloyd, Nancy; Lelgemann, Monika; Bühler, Diedrich; Schünemann, Holger J

2017-12-01

The objective of the study was to describe and compare current practices in developing guidelines about the use of healthcare-related tests and diagnostic strategies (HCTDS). We sampled 37 public health and clinical practice guidelines about HCTDS from various sources without language restrictions. Detailed descriptions of the systems used to assess the quality of evidence and develop recommendations were challenging to find within guidelines. We observed much variability among and within organizations with respect to how they develop recommendations about HCTDS. Twenty-four percent of the guidelines did not consider health benefits and harms but based decisions solely on test accuracy. We did not identify guidelines that described the main potential care pathways involving tests for a healthcare problem. In addition, we did not identify guidelines that systematically assessed, described, and referenced the evidence that linked test accuracy and patient-important outcomes. There is considerable variability among the processes used and factors considered in developing recommendations about the use of tests. This variability may be the cause for the disagreement we observed in recommendations about testing for the same condition. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnostic value of FIB-4 for liver fibrosis in patients with hepatitis B: a meta-analysis of diagnostic test.

PubMed

Yin, Zhi; Zou, Jin; Li, Qiongxuan; Chen, Lizhang

2017-04-04

This study is aimed at evaluating the diagnostic value of FIB-4 for liver fibrosis in patients with hepatitis B through a meta-analysis of diagnostic test. We conducted a comprehensive search in the Pubmed, Embase, Web of Science, and Chinese National Knowledge Infrastructure before October 31, 2016. Stata 14.0 software was used for calculation and statistical analyses. We used the sensitivity, specificity, positive and negative likelihood ratio (PLR, NLR), diagnostic odds ratio (DOR) and 95% confidence intervals (CIs) to evaluate the diagnostic value of FIB-4 for liver fibrosis in patients with hepatitis B. Twenty-six studies were included in the final analyses, with a total of 8274 individuals. The pooled parameters are calculated from all studies: sensitivity of 0.69 (95%CI:0.63-0.75), specificity of 0.81 (95%CI: 0.73-0.87), PLR of 3.63 (95%CI:2.66-4.94), NLR of 0.38 (95%CI:0.32-0.44), DOR of 9.57 (95%CI: 6.67-13.74), and area under the curve (AUC) of 0.80 (95%CI: 0.76-0.83). We also conducted subgroup based on the range of cut-off values. Results from subgroup analysis showed that cut-off was the source of heterogeneity in the present study. The sensitivity and specificity of cut-off>2 were 0.69 and 0.95 with the AUC of 0.90 (95%CI: 0.87-0.92). The overall diagnostic value of FIB-4 is not very high for liver fibrosis in patients with hepatitis B. However, the diagnostic value is affected by the cut-off value. FIB-4 has relatively high diagnostic value for detecting liver fibrosis in patients with hepatitis B when the diagnostic threshold value is more than 2.0.

Conversion-Integration of MSFC Nonlinear Signal Diagnostic Analysis Algorithms for Realtime Execution of MSFC's MPP Prototype System

NASA Technical Reports Server (NTRS)

Jong, Jen-Yi

1996-01-01

NASA's advanced propulsion system Small Scale Magnetic Disturbances/Advanced Technology Development (SSME/ATD) has been undergoing extensive flight certification and developmental testing, which involves large numbers of health monitoring measurements. To enhance engine safety and reliability, detailed analysis and evaluation of the measurement signals are mandatory to assess its dynamic characteristics and operational condition. Efficient and reliable signal detection techniques will reduce the risk of catastrophic system failures and expedite the evaluation of both flight and ground test data, and thereby reduce launch turn-around time. During the development of SSME, ASRI participated in the research and development of several advanced non- linear signal diagnostic methods for health monitoring and failure prediction in turbomachinery components. However, due to the intensive computational requirement associated with such advanced analysis tasks, current SSME dynamic data analysis and diagnostic evaluation is performed off-line following flight or ground test with a typical diagnostic turnaround time of one to two days. The objective of MSFC's MPP Prototype System is to eliminate such 'diagnostic lag time' by achieving signal processing and analysis in real-time. Such an on-line diagnostic system can provide sufficient lead time to initiate corrective action and also to enable efficient scheduling of inspection, maintenance and repair activities. The major objective of this project was to convert and implement a number of advanced nonlinear diagnostic DSP algorithms in a format consistent with that required for integration into the Vanderbilt Multigraph Architecture (MGA) Model Based Programming environment. This effort will allow the real-time execution of these algorithms using the MSFC MPP Prototype System. ASRI has completed the software conversion and integration of a sequence of nonlinear signal analysis techniques specified in the SOW for real-time execution on MSFC's MPP Prototype. This report documents and summarizes the results of the contract tasks; provides the complete computer source code; including all FORTRAN/C Utilities; and all other utilities/supporting software libraries that are required for operation.

Tritium assay of Li sub 2 O pellets in the LBM/LOTUS experiments

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

Quanci, J.; Azam, S.; Bertone, P.

1986-01-01

One of the objectives of the Lithium Blanket Module (LBM) program is to test the ability of advanced neutronics codes to model the tritium breeding characteristics of a fusion blanket exposed to a toroidal fusion neutron source. The LBM consists of over 20,000 cylindrical lithium oxide pellets and numerous diagnostic pellets and wafers. The LBM has been irradiated at the Ecole Polytechnique Federale de Lausanne (EPFL) LOTUS facility with a Haefely sealed neutron generator that gives a point deuterium-tritium neutron source up to 5 {times} 10{sup 12} 14-MeV n/s. Both Princeton Plasma Physics Laboratory (PPL) and EPFL assayed the tritiummore » bred at various positions in the LBM. EPFL employed a dissolution technique while PPL recovered the tritium by a thermal extraction method. EPFL uses 0.38-g, 75% TD, lithium oxide diagnostic wafers to evaluate the tritium bred in the LBM. PPPL employs a thermal extraction method to determine the tritium bred in lithium oxide samples. In the initial experiments, diagnostic pellets and wafers were placed at five locations in the LBM central removable test rod at distances of 3, 9, 21, 36, and 48 cm from the front face of the module. The two sets of data for the tritium bred in the LBM along its centerline as a function of distance from the front face of the module were compared with each other, and with the predictions of two-dimensional neutronics codes. 1 ref.« less

Laboratory study of the spectrum of highly ionized calcium in the 100-250 A range applied to solar flare diagnostics

NASA Technical Reports Server (NTRS)

Lippmann, S.; Finkenthal, M.; Huang, L. K.; Moos, H. W.; Stratton, B. C.; Yu, T. L.; Bhatia, A. K.

1987-01-01

Calcium was introduced into the TEXT tokamak, and its spectral emission was recorded in the 50-360 A range by an absolutely calibrated grazing incidence spectrometer. These observations of highly ionized species of calcium at known conditions of plasma electron temperature and density allow testing of line brightness ratio predictions based on theoretical values of temperature-dependent electron excitation rates. The confirmation of the expected ratios in Be I-like to O I-like calcium allows more confident use of these ratios as a density diagnostic of remote astrophysical sources such as solar flares.

Comparative Soot Diagnostics: 1 Year Report

NASA Technical Reports Server (NTRS)

Urban, David L.; Griffin, DeVon W.; Gard, Melissa Y.

1998-01-01

The motivation for the Comparative Soot Diagnostics (CSD) experiment lies in the broad practical importance of understanding combustion generated particulate. Depending upon the circumstances, particulate matter can affect the durability and performance of combustion equipment, can be a pollutant, can be used to detect fires and, in the form of soot, can be the dominant source of radiant energy from flames. Bright sooty fires are desirable for efficient energy extraction in furnaces and power equipment. In contrast, soot-enhanced radiation is undesirable in many propulsion systems (e.g. jet engines). The non-buoyant structure of most flames of practical interest (turbulent) makes understanding of soot processes in low gravity flames important to our ability to predict fire behavior on earth. These studies also have direct applications to fire safety in human-crew spacecraft, since smoke is the indicator used for automated detection in current spacecraft. In addition, recent tests conducted on MIR showed that a candle in a truly quiescent spacecraft environment can burn for tens of minutes. Consequently, this test and many earlier tests have demonstrated that fires in spacecraft can be considered a credible risk. In anticipation of this risk, NASA has included fire detectors on Skylab, smoke detectors on the Space Shuttle (STS), and smoke detectors in the design for the International Space Station (ISS). In the CSD experiment, these smoke detectors were tested using, quasi-steady, low-gravity, particulate generating materials. Samples of the particulate were also obtained from these low-gravity sources. This experiment provides the first such measurements aimed toward understanding of soot processes here on earth and for the testing and design of advanced spacecraft smoke detection systems. This paper describes the operation and preliminary results of the CSD experiment which was was conducted in the Middeck Glovebox Facility (MGBX) on USMP-3. The objectives of CSD are to examine the particulate emission from a variety of pyrolyzing and combusting sources and to quantify the performance of several particulate-sensing diagnostic techniques. This paper presents the results of the microgravity portion of the CSD experiment. The results include the temporal response of the detectors and average sizes of the primary and aggregate particles captured on the thermophoretic probes. Complete assessment of the microgravity data and its combination with the normal-gravity data are still in process.

Diagnostic Ability of Wide-field Retinal Nerve Fiber Layer Maps Using Swept-Source Optical Coherence Tomography for Detection of Preperimetric and Early Perimetric Glaucoma.

PubMed

Lee, Won June; Na, Kyeong Ik; Kim, Young Kook; Jeoung, Jin Wook; Park, Ki Ho

2017-06-01

To evaluate the diagnostic ability of wide-field retinal nerve fiber layer (RNFL) maps with swept-source optical coherence tomography (SS-OCT) for detection of preperimetric (PPG) and early perimetric glaucoma (EG). One hundred eighty-four eyes, including 67 healthy eyes, 43 eyes with PPG, and 74 eyes with EG, were analyzed. Patients underwent a comprehensive ocular examination including red-free RNFL photography, visual field testing and wide-field SS-OCT scanning (DRI-OCT-1 Atlantis; Topcon, Tokyo, Japan). SS-OCT provides a wide-field RNFL thickness map and a SuperPixel map, which are composed of the RNFL deviation map of the peripapillary area and the deviation map of the composition of the ganglion cell layer with the inner plexiform layer and RNFL (GC-IPL+RNFL) in the macular area. The ability to discriminate PPG and EG from healthy eyes was assessed using sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) for all parameters and criteria provided by the wide-field SS-OCT scan. The wide-field RNFL thickness map using SS-OCT showed the highest sensitivity of PPG-diagnostic and EG-diagnostic performance compared with the other SS-OCT criteria based on the internal normative base (93.0 and 97.3%, respectively). Among the SS-OCT continuous parameters, the RFNL thickness of the 7 clock-hour, inferior and inferotemporal macular ganglion cell analyses showed the largest AUC of PPG-diagnostic and EG-diagnostic performance (AUC=0.809 to 0.865). The wide-field RNFL thickness map using SS-OCT performed well in distinguishing eyes with PPG and EG from healthy eyes. In the clinical setting, wide-field RNFL maps of SS-OCT can be useful tools for detection of early-stage glaucoma.

Diagnostic value of two commercial chromatographic "patient-side" tests in the diagnosis of acute canine leptospirosis.

PubMed

Gloor, C I; Schweighauser, A; Francey, T; Rodriguez-Campos, S; Vidondo, B; Bigler, B; Schuller, S

2017-03-01

To determine the diagnostic performance of two patient-side tests (RDT-1: Test-it™ and RDT-2 Witness®Lepto) in the early diagnosis of canine leptospirosis. Retrospective study of 108 dogs with leptospirosis and 53 controls. Leptospirosis was diagnosed based on compatible clinical and clinicopathologic signs and either a single microscopic agglutination test titre_ >800 (n=49), seroconversion (n=53), positive urine real time PCR (RT-PCR) (n=1), evidence of spirochaetes in silver-stained tissues (n=1) or a combination of these (n=4). Leptospirosis was excluded in dogs with a convincing alternative diagnosis and single microscopic agglutination testing titres _<200 (n=46) or lack of seroconversion (n=7). Indices of diagnostic accuracy of the rapid diagnostic tests were calculated by comparing admission rapid diagnostic test results to the final disease status. Rapid diagnostic test-1 was performed in 118 dogs, rapid diagnostic test-2 in 69 dogs and both tests in 26 dogs. Weak positive results occurred frequently representing 22·6% (rapid diagnostic test-1) and 32·3% (rapid diagnostic test-2) of all positive tests in dogs with leptospirosis. If weak positive rapid diagnostic tests were considered positive, rapid diagnostic test-1 and rapid diagnostic test-2 had sensitivities of 82 and 76%, specificities of 91 and 100%, positive predictive values of 94% and 100% and negative predictive values of 73% and 74%, respectively. There were some technical problems with rapid diagnostic test-1. The diagnostic performance of the rapid diagnostic tests is similar to that reported for the microscopic agglutination test. Both can support a diagnosis of leptospirosis with high specificity but leptospirosis cannot be excluded based on a negative admission test result. Both RDTs are useful in conjunction with other confirmatory tests. © 2017 British Small Animal Veterinary Association.

Distribution of Acanthamoeba Genotypes Isolated from Recreational and Therapeutic Geothermal Water Sources in Southwestern Iran

PubMed Central

Niyyati, Maryam; Saberi, Reza; Latifi, Alireza; Lasjerdi, Zohreh

2016-01-01

A comprehensive survey was conducted along 10 km of geothermal rivers in southwestern Iran. A total of 40 water samples were tested for the presence of Acanthamoeba spp., and genotypes were determined by targeting the diagnostic fragment 3 region of the 18S rRNA gene. The pathogenic potential of all positive isolates was also identified using tolerance ability test. High occurrences of Acanthamoeba (50%) were detected in the sampling areas. Based on sequencing analysis, isolates belonging to T4 (93.7%) and T2 (6.25%) genotypes were reported. Thermo- and osmotolerance tests revealed that five strains are highly pathogenic. Since every collection site of this study was associated with high human activity, posting of warning signs, monitoring of recreational water sources, and awareness of high-risk people are of utmost importance. To the best of our knowledge, the present research is the first to report T2 genotype from geothermal water sources in Iran. PMID:27127409

Distribution of Acanthamoeba Genotypes Isolated from Recreational and Therapeutic Geothermal Water Sources in Southwestern Iran.

PubMed

Niyyati, Maryam; Saberi, Reza; Latifi, Alireza; Lasjerdi, Zohreh

2016-01-01

A comprehensive survey was conducted along 10 km of geothermal rivers in southwestern Iran. A total of 40 water samples were tested for the presence of Acanthamoeba spp., and genotypes were determined by targeting the diagnostic fragment 3 region of the 18S rRNA gene. The pathogenic potential of all positive isolates was also identified using tolerance ability test. High occurrences of Acanthamoeba (50%) were detected in the sampling areas. Based on sequencing analysis, isolates belonging to T4 (93.7%) and T2 (6.25%) genotypes were reported. Thermo- and osmotolerance tests revealed that five strains are highly pathogenic. Since every collection site of this study was associated with high human activity, posting of warning signs, monitoring of recreational water sources, and awareness of high-risk people are of utmost importance. To the best of our knowledge, the present research is the first to report T2 genotype from geothermal water sources in Iran.

Shoulder pain in primary care: diagnostic accuracy of clinical examination tests for non-traumatic acromioclavicular joint pain

PubMed Central

2013-01-01

Background Despite numerous methodological flaws in previous study designs and the lack of validation in primary care populations, clinical tests for identifying acromioclavicular joint (ACJ) pain are widely utilised without concern for such issues. The aim of this study was to estimate the diagnostic accuracy of traditional ACJ tests and to compare their accuracy with other clinical examination features for identifying a predominant ACJ pain source in a primary care cohort. Methods Consecutive patients with shoulder pain were recruited prospectively from primary health care clinics. Following a standardised clinical examination and diagnostic injection into the subacromial bursa, all participants received a fluoroscopically guided diagnostic block of 1% lidocaine hydrochloride (XylocaineTM) into the ACJ. Diagnostic accuracy statistics including sensitivity, specificity, predictive values, positive and negative likelihood ratios (LR+ and LR-) were calculated for traditional ACJ tests (Active Compression/O’Brien’s test, cross-body adduction, localised ACJ tenderness and Hawkins-Kennedy test), and for individual and combinations of clinical examination variables that were associated with a positive anaesthetic response (PAR) (P≤0.05) defined as 80% or more reduction in post-injection pain intensity during provocative clinical tests. Results Twenty two of 153 participants (14%) reported an 80% PAR. None of the traditional ACJ tests were associated with an 80% PAR (P<0.05) and combinations of traditional tests were not able to discriminate between a PAR and a negative anaesthetic response (AUC 0.507; 95% CI: 0.366, 0.647; P>0.05). Five clinical examination variables (repetitive mechanism of pain onset, no referred pain below the elbow, thickened or swollen ACJ, no symptom provocation during passive glenohumeral abduction and external rotation) were associated with an 80% PAR (P<0.05) and demonstrated an ability to accurately discriminate between an PAR and NAR (AUC 0.791; 95% CI 0.702, 0.880; P<0.001). Less than two positive clinical features resulted in 96% sensitivity (95% CI 0.78, 0.99) and a LR- 0.09 (95% CI 0.02, 0.41) and four positive clinical features resulted in 95% specificity (95% CI 0.90, 0.98) and a LR+ of 4.98 (95% CI 1.69, 13.84). Conclusions In this cohort of primary care patients with predominantly subacute or chronic ACJ pain of non-traumatic onset, traditional ACJ tests were of limited diagnostic value. Combinations of other history and physical examination findings were able to more accurately identify injection-confirmed ACJ pain in this cohort. PMID:23634871

UK NEQAS survey of allergen component testing across the United Kingdom and other European countries

PubMed Central

Saleem, R.; Keymer, C.; Patel, D.; Egner, W.

2017-01-01

Summary The clinical utility of molecular diagnostic approaches in allergy investigation is being recognized increasingly to play a significant role in the management of allergic patients. Determining the sensitization pattern, which is best achieved through the use of component resolved diagnostics (CRD), allows effective risk stratification, appropriate treatment and patient selection for immunotherapy. In order to assess the diagnostic service provisions for in‐vitro allergy testing across Europe, a survey was carried out via the total immunoglobulin (Ig)E and specific IgE external quality assurance schemes run by UK National External Quality Assessment Service (NEQAS) Immunology, Immunochemistry and Allergy. This survey assessed allergy testing, and in particular allergen components offered by the laboratories, and found a wide variability in service provision, particularly between the United Kingdom and other European Union (EU) countries. Furthermore, there was lack of standardization for acquisition of clinical information to aid allergen (and component) selection, gating strategy, testing algorithms and clinical interpretation. Interestingly, a significant proportion of laboratories (the majority from EU) stated that they ‘used’ the results for peanut components for risk stratification. However, the vast majority of participants were unaware of guidelines relating to the use of allergen component testing, and agreed that further education would assist in reaching a common platform. Hence, this survey has highlighted that although CRD has been adopted into routine diagnostics across Europe, it is potentially compromised by lack of standardized protocols and guidance sources. Consequently, there is a need for local or national standards and education through External Quality Assurance services on the performance and application of CRD into allergy investigation. PMID:28423454

Study of a high power hydrogen beam diagnostic based on secondary electron emission

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

Sartori, E., E-mail: emanuele.sartori@igi.cnr.it; Department of Management and Engineering, University di Padova strad. S. Nicola 3, 36100 Vicenza; Panasenkov, A.

2016-11-15

In high power neutral beams for fusion, beam uniformity is an important figure of merit. Knowing the transverse power profile is essential during the initial phases of beam source operation, such as those expected for the ITER heating neutral beam (HNB) test facility. To measure it a diagnostic technique is proposed, based on the collection of secondary electrons generated by beam-surface and beam-gas interactions, by an array of positively biased collectors placed behind the calorimeter tubes. This measurement showed in the IREK test stand good proportionality to the primary beam current. To investigate the diagnostic performances in different conditions, wemore » developed a numerical model of secondary electron emission, induced by beam particle impact on the copper tubes, and reproducing the cascade of secondary emission caused by successive electron impacts. The model is first validated against IREK measurements. It is then applied to the HNB case, to assess the locality of the measurement, the proportionality to the beam current density, and the influence of beam plasma.« less

A user-friendly, open-source tool to project impact and cost of diagnostic tests for tuberculosis

PubMed Central

Dowdy, David W; Andrews, Jason R; Dodd, Peter J; Gilman, Robert H

2014-01-01

Most models of infectious diseases, including tuberculosis (TB), do not provide results customized to local conditions. We created a dynamic transmission model to project TB incidence, TB mortality, multidrug-resistant (MDR) TB prevalence, and incremental costs over 5 years after scale-up of nine alternative diagnostic strategies. A corresponding web-based interface allows users to specify local costs and epidemiology. In settings with little capacity for up-front investment, same-day microscopy had the greatest impact on TB incidence and became cost-saving within 5 years if delivered at $10/test. With greater initial investment, population-level scale-up of Xpert MTB/RIF or microcolony-based culture often averted 10 times more TB cases than narrowly-targeted strategies, at minimal incremental long-term cost. Xpert for smear-positive TB had reasonable impact on MDR-TB incidence, but at substantial price and little impact on overall TB incidence and mortality. This user-friendly modeling framework improves decision-makers' ability to evaluate the local impact of TB diagnostic strategies. DOI: http://dx.doi.org/10.7554/eLife.02565.001 PMID:24898755

Modeling and simulation of a beam emission spectroscopy diagnostic for the ITER prototype neutral beam injector

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

Barbisan, M., E-mail: marco.barbisan@igi.cnr.it; Zaniol, B.; Pasqualotto, R.

2014-11-15

A test facility for the development of the neutral beam injection system for ITER is under construction at Consorzio RFX. It will host two experiments: SPIDER, a 100 keV H{sup −}/D{sup −} ion RF source, and MITICA, a prototype of the full performance ITER injector (1 MV, 17 MW beam). A set of diagnostics will monitor the operation and allow to optimize the performance of the two prototypes. In particular, beam emission spectroscopy will measure the uniformity and the divergence of the fast particles beam exiting the ion source and travelling through the beam line components. This type of measurementmore » is based on the collection of the H{sub α}/D{sub α} emission resulting from the interaction of the energetic particles with the background gas. A numerical model has been developed to simulate the spectrum of the collected emissions in order to design this diagnostic and to study its performance. The paper describes the model at the base of the simulations and presents the modeled H{sub α} spectra in the case of MITICA experiment.« less

Power Balance Analysis of the Prototype-Material Plasma Exposure eXperiment

NASA Astrophysics Data System (ADS)

Showers, M. A.; Biewer, T. M.; Caneses, J. F.; Caughman, J. B. O.; Lumsdaine, A.; Owen, L.; Rapp, J.; Youchison, D.; Beers, C. J.; Donovan, D. C.; Kafle, N.; Ray, H. B.

2017-10-01

The Prototype-Material Plasma Exposure eXperiment (Proto-MPEX) is a test bed for the plasma source concept for the planned Material Plasma Exposure eXperiment (MPEX), a steady-state linear device studying plasma material interactions for fusion reactors. A power balance of Proto-MPEX attempts to identify machine operating parameters that will improve Proto-MPEX's performance, potentially impacting the MPEX design concept. A power balance has been performed utilizing an extensive diagnostic suite to identify mechanisms and locations of power loss from the main plasma. The diagnostic package includes infrared cameras, double Langmuir probes, fluoroptic probes, Mach probes, a Thomson scattering diagnostic, a McPherson spectrometer and in-vessel thermocouples. Radiation losses are estimated with absolute calibrated spectroscopic signals. This work was supported by the U.S. D.O.E. contract DE-AC05-00OR22725.

40 CFR 85.2223 - On-board diagnostic test report.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 18 2010-07-01 2010-07-01 false On-board diagnostic test report. 85... Tests § 85.2223 On-board diagnostic test report. (a) Motorists whose vehicles fail the on-board diagnostic test described in § 85.2222 shall be provided with the on-board diagnostic test results, including...

40 CFR 85.2223 - On-board diagnostic test report.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 18 2011-07-01 2011-07-01 false On-board diagnostic test report. 85... Tests § 85.2223 On-board diagnostic test report. (a) Motorists whose vehicles fail the on-board diagnostic test described in § 85.2222 shall be provided with the on-board diagnostic test results, including...

Multi-method automated diagnostics of rotating machines

NASA Astrophysics Data System (ADS)

Kostyukov, A. V.; Boychenko, S. N.; Shchelkanov, A. V.; Burda, E. A.

2017-08-01

The automated machinery diagnostics and monitoring systems utilized within the petrochemical plants are an integral part of the measures taken to ensure safety and, as a consequence, the efficiency of these industrial facilities. Such systems are often limited in their functionality due to the specifics of the diagnostic techniques adopted. As the diagnostic techniques applied in each system are limited, and machinery defects can have different physical nature, it becomes necessary to combine several diagnostics and monitoring systems to control various machinery components. Such an approach is inconvenient, since it requires additional measures to bring the diagnostic results in a single view of the technical condition of production assets. In this case, we mean by a production facility a bonded complex of a process unit, a drive, a power source and lines. A failure of any of these components will cause an outage of the production asset, which is unacceptable. The purpose of the study is to test a combined use of vibration diagnostics and partial discharge techniques within the diagnostic systems of enterprises for automated control of the technical condition of rotating machinery during maintenance and at production facilities. The described solutions allow you to control the condition of mechanical and electrical components of rotating machines. It is shown that the functionality of the diagnostics systems can be expanded with minimal changes in technological chains of repair and operation of rotating machinery. Automation of such systems reduces the influence of the human factor on the quality of repair and diagnostics of the machinery.

42 CFR 415.180 - Teaching setting requirements for the interpretation of diagnostic radiology and other diagnostic...

Code of Federal Regulations, 2011 CFR

2011-10-01

... interpretation of diagnostic radiology and other diagnostic tests. 415.180 Section 415.180 Public Health CENTERS... for the interpretation of diagnostic radiology and other diagnostic tests. (a) General rule. Physician fee schedule payment is made for the interpretation of diagnostic radiology and other diagnostic tests...

42 CFR 415.180 - Teaching setting requirements for the interpretation of diagnostic radiology and other diagnostic...

Code of Federal Regulations, 2010 CFR

2010-10-01

... interpretation of diagnostic radiology and other diagnostic tests. 415.180 Section 415.180 Public Health CENTERS... for the interpretation of diagnostic radiology and other diagnostic tests. (a) General rule. Physician fee schedule payment is made for the interpretation of diagnostic radiology and other diagnostic tests...

Validation of a serum neutralization test for detection of antibodies specific to cyprinid herpesvirus 3 in infected common and koi carp (Cyprinus carpio).

PubMed

Cabon, J; Louboutin, L; Castric, J; Bergmann, S; Bovo, G; Matras, M; Haenen, O; Olesen, N J; Morin, T

2017-05-01

Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of a serious infective, notifiable disease affecting common carp and varieties. In survivors, infection is generally characterized by a subclinical latency phase with restricted viral replication. The CyHV-3 genome is difficult to detect in such carrier fish that represent a potential source of dissemination if viral reactivation occurs. In this study, the analytical and diagnostic performance of an alternative serum neutralization (SN) method based on the detection of CyHV-3-specific antibodies was assessed using 151 serum or plasma samples from healthy and naturally or experimentally CyHV-3-infected carp. French CyHV-3 isolate 07/108b was neutralized efficiently by sera from carp infected with European, American and Taiwanese CyHV-3 isolates, but no neutralization was observed using sera specific to other aquatic herpesviruses. Diagnostic sensitivity, diagnostic specificity and repeatability of 95.9%, 99.0% and 99.3%, respectively, were obtained, as well as a compliance rate of 89.9% in reproducibility testing. Neutralizing antibodies were steadily detected in infected carp subjected to restrictive or permissive temperature variations over more than 25 months post-infection. The results suggest that this non-lethal diagnostic test could be used in the future to improve the epidemiological surveillance and control of CyHV-3 disease. © 2016 John Wiley & Sons Ltd.

Toxoplasma gondii Recombinant Antigens as Tools for Serodiagnosis of Human Toxoplasmosis: Current Status of Studies

PubMed Central

2013-01-01

Toxoplasma gondii is a parasitic protozoan which is the cause of toxoplasmosis. Although human toxoplasmosis in healthy adults is usually asymptomatic, serious disease can occur in the case of congenital infections and immunocompromised individuals. Furthermore, despite the exact recognition of its etiology, it still presents a diagnostic problem. Diagnosis of toxoplasmosis is mainly based on the results of serological tests detecting anti-T. gondii-specific antibodies in the patient's serum sample. The specificities and sensitivities of serology tests depend mostly on the diagnostic antigen(s) used. Most of the commercial serological kits currently available are based on Toxoplasma lysate antigens (TLAs). In recent years, many studies showed that recombinant antigenic proteins of T. gondii may be an alternative source of antigens which are very useful for the serodiagnosis of toxoplasmosis. This article presents a review of current studies on the application and usefulness of different T. gondii recombinant antigens in serological tests for the diagnosis of human toxoplasmosis. PMID:23784855

"Shotgun" versus sequential testing. Cost-effectiveness of diagnostic strategies for vaginitis.

PubMed

Carr, Phyllis L; Rothberg, Michael B; Friedman, Robert H; Felsenstein, Donna; Pliskin, Joseph S

2005-09-01

Although vaginitis is a common outpatient problem, only 60% of patients can be diagnosed at the initial office visit of a primary care provider using the office procedures of pH testing, whiff tests, normal saline, and potassium hydroxide preps. To determine the most cost-effective diagnostic and treatment approach for the medical management of vaginitis. Decision and cost-effectiveness analyses. Healthy women with symptoms of vaginitis undiagnosed after an initial pelvic exam, wet mount preparations, pH, and the four criteria to diagnose bacterial vaginosis. General office practice. We evaluated 28 diagnostic strategies comprised of combinations of pH testing, vaginal cultures for yeast and Trichomonas vaginalis, Gram's stain for bacterial vaginosis, and DNA probes for Neisseria gonorrhoeae and Chlamydia. Data sources for the study were confined to English language literature. The outcome measures were symptom-days and costs. The least expensive strategy was to perform yeast culture, gonorrhoeae and Chlamydia probes at the initial visit, and Gram's stain and Trichomonas culture only when the vaginal pH exceeded 4.9 (330 dollars, 7.30 symptom days). Other strategies cost 8 dollars to 76 dollars more and increased duration of symptoms by up to 1.3 days. In probabilistic sensitivity analysis, this strategy was always the most effective strategy and was also least expensive 58% of the time. For patients with vaginitis symptoms undiagnosed by pelvic examination, wet mount preparations and related office tests, a comprehensive, pH-guided testing strategy at the initial office visit is less expensive and more effective than ordering tests sequentially.

Optimal Combination of Non-Invasive Tools for the Early Detection of Potentially Life-Threatening Emergencies in Gynecology

PubMed Central

Varas, Catalina; Ravit, Marion; Mimoun, Camille; Panel, Pierre; Huchon, Cyrille; Fauconnier, Arnaud

2016-01-01

Objectives Potentially life-threatening gynecological emergencies (G-PLEs) are acute pelvic conditions that may spontaneously evolve into a life-threatening situation, or those for which there is a risk of sequelae or death in the absence of prompt diagnosis and treatment. The objective of this study was to identify the best combination of non-invasive diagnostic tools to ensure an accurate diagnosis and timely response when faced with G-PLEs for patients arriving with acute pelvic pain at the Gynecological Emergency Department (ED). Methods The data on non-invasive diagnostic tools were sourced from the records of patients presenting at the ED of two hospitals in the Parisian suburbs (France) with acute pelvic pain between September 2006 and April 2008. The medical history of the patients was obtained through a standardized questionnaire completed for a prospective observational study, and missing information was completed with data sourced from the medical forms. Diagnostic tool categories were predefined as a collection of signs or symptoms. We analyzed the association of each sign/symptom with G-PLEs using Pearson’s Chi-Square or Fischer’s exact tests. Symptoms and signs associated with G-PLEs (p-value < 0.20) were subjected to logistic regression to evaluate the diagnostic value of each of the predefined diagnostic tools and in various combinations. Results The data of 365 patients with acute pelvic pain were analyzed, of whom 103 were confirmed to have a PLE. We analyzed five diagnostic tools by logistic regression: Triage Process, History-Taking, Physical Examination, Ultrasonography, and Biological Exams. The combination of History-Taking and Ultrasonography had a C-index of 0.83, the highest for a model combining two tools. Conclusions The use of a standardized self-assessment questionnaire for history-taking and focal ultrasound examination were found to be the most successful tool combination for the diagnosis of gynecological emergencies in a Gynecological ED. Additional tools, such as physical examination, do not add substantial diagnostic value. PMID:27583697

Feasibility of streamlining an interactive Bayesian-based diagnostic support tool designed for clinical practice

NASA Astrophysics Data System (ADS)

Chen, Po-Hao; Botzolakis, Emmanuel; Mohan, Suyash; Bryan, R. N.; Cook, Tessa

2016-03-01

In radiology, diagnostic errors occur either through the failure of detection or incorrect interpretation. Errors are estimated to occur in 30-35% of all exams and contribute to 40-54% of medical malpractice litigations. In this work, we focus on reducing incorrect interpretation of known imaging features. Existing literature categorizes cognitive bias leading a radiologist to an incorrect diagnosis despite having correctly recognized the abnormal imaging features: anchoring bias, framing effect, availability bias, and premature closure. Computational methods make a unique contribution, as they do not exhibit the same cognitive biases as a human. Bayesian networks formalize the diagnostic process. They modify pre-test diagnostic probabilities using clinical and imaging features, arriving at a post-test probability for each possible diagnosis. To translate Bayesian networks to clinical practice, we implemented an entirely web-based open-source software tool. In this tool, the radiologist first selects a network of choice (e.g. basal ganglia). Then, large, clearly labeled buttons displaying salient imaging features are displayed on the screen serving both as a checklist and for input. As the radiologist inputs the value of an extracted imaging feature, the conditional probabilities of each possible diagnosis are updated. The software presents its level of diagnostic discrimination using a Pareto distribution chart, updated with each additional imaging feature. Active collaboration with the clinical radiologist is a feasible approach to software design and leads to design decisions closely coupling the complex mathematics of conditional probability in Bayesian networks with practice.

A Novel Field-Deployable Point-of-Care Diagnostic Test for Cutaneous Leishmaniasis

DTIC Science & Technology

2017-10-01

Leishmaniasis PRINCIPAL INVESTIGATOR: LT. Danett K. Bishop CONTRACTING ORGANIZATION: The Henry M. Jackson for the Advancement of Military Medicine Bethesda...21702-5012 DISTRIBUTION STATEMENT: Approved for Public Release; Distribution Unlimited The views, opinions and/or findings contained in this...estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the

42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... in the 80000 series of the Current Procedural Terminology published by the American Medical... & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL INSURANCE (SMI) BENEFITS Medical and Other Health Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory...

42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Procedural Terminology published by the American Medical Association. (3) Levels of supervision. Except where... & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL INSURANCE (SMI) BENEFITS Medical and Other Health Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory...

Development of departmental standard for traceability of measured activity for I-131 therapy capsules used in nuclear medicine.

PubMed

Ravichandran, Ramamoorthy; Binukumar, Jp

2011-01-01

International Basic Safety Standards (International Atomic Energy Agency, IAEA) provide guidance levels for diagnostic procedures in nuclear medicine indicating the maximum usual activity for various diagnostic tests in terms of activities of injected radioactive formulations. An accuracy of ± 10% in the activities of administered radio-pharmaceuticals is being recommended, for expected outcome in diagnostic and therapeutic nuclear medicine procedures. It is recommended that the long-term stability of isotope calibrators used in nuclear medicine is to be checked periodically for their performance using a long-lived check source, such as Cs-137, of suitable activity. In view of the un-availability of such a radioactive source, we tried to develop methods to maintain traceability of these instruments, for certifying measured activities for human use. Two re-entrant chambers [(HDR 1000 and Selectron Source Dosimetry System (SSDS)] with I-125 and Ir-192 calibration factors in the Department of Radiotherapy were used to measure Iodine-131 (I-131) therapy capsules to establish traceability to Mark V isotope calibrator of the Department of Nuclear Medicine. Special nylon jigs were fabricated to keep I-131 capsule holder in position. Measured activities in all the chambers showed good agreement. The accuracy of SSDS chamber in measuring Ir-192 activities in the last 5 years was within 0.5%, validating its role as departmental standard for measuring activity. The above method is adopted because mean energies of I-131 and Ir-192 are comparable.

Special physical examination tests for superior labrum anterior-posterior shoulder tears: an examination of clinical usefulness.

PubMed

Sandrey, Michelle A

2013-01-01

Calvert E, Chambers GK, Regan W, Hawkins RH, Leith JM. Special physical examination tests for superior labrum anterior-posterior shoulder injuries are clinically limited and invalid: a diagnostic systematic review. J Clin Epidemiol. 2009;62(5):558-563. The systematic review focused on diagnostic accuracy studies to determine if evidence was sufficient to support the use of superior labrum anterior-posterior (SLAP) physical examination tests as valid and reliable. The primary question was whether there was sufficient evidence in the published literature to support the use of SLAP physical examination tests as valid and reliable diagnostic test procedures. Studies published in English were identified through database searches on MEDLINE, EMBASE, and the Cochrane database (1970-2004) using the search term SLAP lesions. The medical subject headings of arthroscopy, shoulder joint, and athletic injuries were combined with test or testing, physical examination, and sensitivity and specificity to locate additional sources. Other sources were identified by rereviewing the reference lists of included studies and review articles. Studies were eligible based on the following criteria: (1) published in English, (2) focused on the physical examination of SLAP lesions, and (3) presented original data. A study was excluded if the article was limited to a clinical description of 1 or more special tests without any research focus to provide clinical accuracy data or if it did not focus on the topic. The abstracts that were located through the search strategies were reviewed, and potentially relevant abstracts were selected. Strict epidemiologic methods were used to obtain and collate all relevant studies; the authors developed a study questionnaire to record study name, year of publication, study design, sample size, and statistics. Validity of the diagnostic test study was determined by applying the 5 criteria proposed by Calvert et al. If the study met the inclusion and validity criteria, 95% confidence intervals were calculated for each sensitivity, specificity, and positive and negative likelihood ratio reported. No specific information was provided about the procedure if the reviewers disagreed on how the evaluation criteria were applied. The specific search criteria led to the identification of 29 full-text articles. The studies were reviewed, and inclusion and exclusion criteria were applied. This resulted in 14 excluded studies and 15 eligible studies for analysis. Of the 15 eligible studies, 1 evaluated only a single physical examination test for a SLAP lesion or biceps tendon injury, and 10 studies evaluated 2 to 6 physical examination tests for a SLAP lesion or biceps tendon injury. Nine studies reported sensitivities and specificities greater than 75%, 4 had sensitivities less than 75%, 3 had specificities less than 75%, 1 did not report sensitivity, and 2 did not report specificities. When validity was assessed for those 15 papers, only 1 study that evaluated the biceps tendon met the 5 critical appraisal criteria of Calvert et al and calculated 95% confidence intervals. When the Speed and Yergason tests were each compared with the gold standard (arthroscopy), the confidence intervals for the positive and negative likelihood ratios spanned 1. This indicated that the test result is unlikely to change the odds of having or not having the condition, respectively. The literature currently used as a reference for teaching in medical schools and continuing education lacks the necessary validity to help rule in or out a SLAP lesion or biceps tendon involvement. Based on the results from the systematic review conducted by Calvert et al, no tests clinically diagnose a SLAP lesion. This is a cause for concern as magnetic resonance imaging or magnetic resonance arthrography, which are frequently used to assess a possible SLAP lesion, may also have diagnostic flaws and may be cost prohibitive. Performing arthroscopy on every patient to rule the condition in or out is unethical, especially if a SLAP lesion is not present. More rigorous validity studies should be conducted for SLAP lesion physical examination tests using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool or Standards for Reporting Diagnostic Accuracy (STARD) criteria.

Overview of the electric propulsion plasma diagnostics suite for the VASIMR VX-200 testbed

NASA Astrophysics Data System (ADS)

Olsen, Christopher; Longmier, Benjamin; Ballenger, Maxwell; Squire, Jared; Glover, Tim; Carter, Mark; Bering, Edgar; Giambusso, Matthew

2012-10-01

Descriptions of the various plasma diagnostics and data analysis methods are given for instruments used in high power (> 100 kW) electric propulsion testing. These include planar Langmuir probes, an articulating retarding potential analyzer, a double Langmuir probe, a multi-axis magnetometer, a high frequency electric field probe, microwave interferometer, and momentum flux targets. These diagnostics have been used to measure the efficiencies of the thruster, plasma source, ion cyclotron resonance booster, and magnetic nozzle as well as used to explore physical phenomena in the plume such as ion/electron detachment, plasma turbulence, and magnetic field line stretching. Typical plume parameters range up to 10^13 cm-3 electron density, 1 kG applied magnetic fields, ion energies in excess of 150 eV, and cold electrons (2 -- 5 eV) with a spatial measurement range over 2 m.

Detector for imaging and dosimetry of laser-driven epithermal neutrons by alpha conversion

NASA Astrophysics Data System (ADS)

Mirfayzi, S. R.; Alejo, A.; Ahmed, H.; Wilson, L. A.; Ansell, S.; Armstrong, C.; Butler, N. M. H.; Clarke, R. J.; Higginson, A.; Notley, M.; Raspino, D.; Rusby, D. R.; Borghesi, M.; Rhodes, N. J.; McKenna, P.; Neely, D.; Brenner, C. M.; Kar, S.

2016-10-01

An epithermal neutron imager based on detecting alpha particles created via boron neutron capture mechanism is discussed. The diagnostic mainly consists of a mm thick Boron Nitride (BN) sheet (as an alpha converter) in contact with a non-borated cellulose nitride film (LR115 type-II) detector. While the BN absorbs the neutrons in the thermal and epithermal ranges, the fast neutrons register insignificantly on the detector due to their low neutron capture and recoil cross-sections. The use of solid-state nuclear track detectors (SSNTD), unlike image plates, micro-channel plates and scintillators, provide safeguard from the x-rays, gamma-rays and electrons. The diagnostic was tested on a proof-of-principle basis, in front of a laser driven source of moderated neutrons, which suggests the potential of using this diagnostic (BN+SSNTD) for dosimetry and imaging applications.

Cushing Syndrome: Diagnostic Workup and Imaging Features, With Clinical and Pathologic Correlation.

PubMed

Wagner-Bartak, Nicolaus A; Baiomy, Ali; Habra, Mouhammed Amir; Mukhi, Shalini V; Morani, Ajaykumar C; Korivi, Brinda R; Waguespack, Steven G; Elsayes, Khaled M

2017-07-01

Cushing syndrome (CS) is a constellation of clinical signs and symptoms resulting from chronic exposure to excess cortisol, either exogenous or endogenous. Exogenous CS is most commonly caused by administration of glucocorticoids. Endogenous CS is subdivided into two types: adrenocorticotropic hormone (ACTH) dependent and ACTH independent. Cushing disease, which is caused by a pituitary adenoma, is the most common cause of ACTH-dependent CS for which pituitary MRI can be diagnostic, with bilateral inferior petrosal sinus sampling useful in equivocal cases. In ectopic ACTH production, which is usually caused by a tumor in the thorax (e.g., small cell lung carcinoma, bronchial and thymic carcinoids, or medullary thyroid carcinoma) or abdomen (e.g., gastroenteropancreatic neuroendocrine tumors or pheochromocytoma), CT, MRI, and nuclear medicine tests are used for localizing the source of ACTH. In ACTH-independent CS, which is caused by various adrenal abnormalities, adrenal protocol CT or MRI is usually diagnostic.

STARD 2015: An Updated List of Essential Items for Reporting Diagnostic Accuracy Studies.

PubMed

Bossuyt, Patrick M; Reitsma, Johannes B; Bruns, David E; Gatsonis, Constantine A; Glasziou, Paul P; Irwig, Les; Lijmer, Jeroen G; Moher, David; Rennie, Drummond; de Vet, Henrica C W; Kressel, Herbert Y; Rifai, Nader; Golub, Robert M; Altman, Douglas G; Hooft, Lotty; Korevaar, Daniël A; Cohen, Jérémie F

2015-12-01

Incomplete reporting has been identified as a major source of avoidable waste in biomedical research. Essential information is often not provided in study reports, impeding the identification, critical appraisal, and replication of studies. To improve the quality of reporting of diagnostic accuracy studies, the Standards for Reporting of Diagnostic Accuracy Studies (STARD) statement was developed. Here we present STARD 2015, an updated list of 30 essential items that should be included in every report of a diagnostic accuracy study. This update incorporates recent evidence about sources of bias and variability in diagnostic accuracy and is intended to facilitate the use of STARD. As such, STARD 2015 may help to improve completeness and transparency in reporting of diagnostic accuracy studies.

ACCURACY OF PLASMA FREE METANEPHRINES IN THE DIAGNOSIS OF PHEOCHROMOCYTOMA AND PARAGANGLIOMA: A SYSTEMATIC REVIEW AND META-ANALYSIS.

PubMed

Chen, Yan; Xiao, Huangmeng; Zhou, Xieda; Huang, Xiaoyu; Li, Yanbing; Xiao, Haipeng; Cao, Xiaopei

2017-10-01

Various studies have validated plasma free metanephrines (MNs) as biomarkers for pheochromocytoma and paraganglioma (PPGL). This meta-analysis aimed to estimate the overall diagnostic accuracy of this biochemical test for PPGL. We searched the PubMed, the Cochrane Library, Web of Science, Embase, Scopus, OvidSP, and ProQuest Dissertations & Theses databases from January 1, 1995 to December 2, 2016 and selected studies written in English that assessed plasma free MNs in the diagnosis of PPGL. Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) was used to evaluate the quality of the included studies. We calculated pooled sensitivities, specificities, positive and negative likelihood ratios, diagnostic odds ratios (DORs) and areas under curve (AUCs) with their 95% confidence intervals (95% CIs). Heterogeneity was assessed by I 2 . To identify the source of heterogeneity, we evaluated the threshold effect and performed a meta-regression. Deeks' funnel plot was selected for investigating any potential publication bias. Although the combination of metanephrine (MN) and normetanephrine (NMN) carried lower specificity (0.94, 95% CI 0.90-0.97) than NMN (0.97, 95% CI 0.92-0.99), NMN was generally more accurate than individual tests, with the highest AUC (0.99, 95% CI 0.97-0.99), DOR (443.35, 95% CI 216.9-906.23), and pooled sensitivity (0.97, 95% CI 0.94-0.98) values. Threshold effect and meta-regression analyses showed that different cut-offs, blood sampling positions, study types and test methods contributed to heterogeneity. This meta-analysis suggested an effective value for combined plasma free MNs for the diagnosis of PPGL, but testing for MNs requires more standardization using tightly regulated studies. AUC = area under curve; CI = confidence interval; DOR = diagnostic odds ratio; EIA = enzyme immunoassay; LC-ECD = liquid chromatography-electrochemical detection; LC-MS/MS = liquid chromatography-tandem mass spectrometry; MN = metanephrine; NMN = normetaneprhine; PPGL = pheochromocytoma and paraganglioma; QUADAS-2 = Quality Assessment of Diagnostic Accuracy Studies 2.

Outcomes of non-invasive diagnostic modalities for the detection of coronary artery disease: network meta-analysis of diagnostic randomised controlled trials

PubMed Central

Siontis, George CM; Mavridis, Dimitris; Greenwood, John P; Coles, Bernadette; Nikolakopoulou, Adriani; Jüni, Peter; Salanti, Georgia

2018-01-01

Abstract Objective To evaluate differences in downstream testing, coronary revascularisation, and clinical outcomes following non-invasive diagnostic modalities used to detect coronary artery disease. Design Systematic review and network meta-analysis. Data sources Medline, Medline in process, Embase, Cochrane Library for clinical trials, PubMed, Web of Science, SCOPUS, WHO International Clinical Trials Registry Platform, and Clinicaltrials.gov. Eligibility criteria for selecting studies Diagnostic randomised controlled trials comparing non-invasive diagnostic modalities in patients presenting with symptoms suggestive of low risk acute coronary syndrome or stable coronary artery disease. Data synthesis A random effects network meta-analysis synthesised available evidence from trials evaluating the effect of non-invasive diagnostic modalities on downstream testing and patient oriented outcomes in patients with suspected coronary artery disease. Modalities included exercise electrocardiograms, stress echocardiography, single photon emission computed tomography-myocardial perfusion imaging, real time myocardial contrast echocardiography, coronary computed tomographic angiography, and cardiovascular magnetic resonance. Unpublished outcome data were obtained from 11 trials. Results 18 trials of patients with low risk acute coronary syndrome (n=11 329) and 12 trials of those with suspected stable coronary artery disease (n=22 062) were included. Among patients with low risk acute coronary syndrome, stress echocardiography, cardiovascular magnetic resonance, and exercise electrocardiograms resulted in fewer invasive referrals for coronary angiography than coronary computed tomographic angiography (odds ratio 0.28 (95% confidence interval 0.14 to 0.57), 0.32 (0.15 to 0.71), and 0.53 (0.28 to 1.00), respectively). There was no effect on the subsequent risk of myocardial infarction, but estimates were imprecise. Heterogeneity and inconsistency were low. In patients with suspected stable coronary artery disease, an initial diagnostic strategy of stress echocardiography or single photon emission computed tomography-myocardial perfusion imaging resulted in fewer downstream tests than coronary computed tomographic angiography (0.24 (0.08 to 0.74) and 0.57 (0.37 to 0.87), respectively). However, exercise electrocardiograms yielded the highest downstream testing rate. Estimates for death and myocardial infarction were imprecise without clear discrimination between strategies. Conclusions For patients with low risk acute coronary syndrome, an initial diagnostic strategy of stress echocardiography or cardiovascular magnetic resonance is associated with fewer referrals for invasive coronary angiography and revascularisation procedures than non-invasive anatomical testing, without apparent impact on the future risk of myocardial infarction. For suspected stable coronary artery disease, there was no clear discrimination between diagnostic strategies regarding the subsequent need for invasive coronary angiography, and differences in the risk of myocardial infarction cannot be ruled out. Systematic review registration PROSPERO registry no CRD42016049442. PMID:29467161

Quarantine for pandemic influenza control at the borders of small island nations.

PubMed

Nishiura, Hiroshi; Wilson, Nick; Baker, Michael G

2009-03-11

Although border quarantine is included in many influenza pandemic plans, detailed guidelines have yet to be formulated, including considerations for the optimal quarantine length. Motivated by the situation of small island nations, which will probably experience the introduction of pandemic influenza via just one airport, we examined the potential effectiveness of quarantine as a border control measure. Analysing the detailed epidemiologic characteristics of influenza, the effectiveness of quarantine at the borders of islands was modelled as the relative reduction of the risk of releasing infectious individuals into the community, explicitly accounting for the presence of asymptomatic infected individuals. The potential benefit of adding the use of rapid diagnostic testing to the quarantine process was also considered. We predict that 95% and 99% effectiveness in preventing the release of infectious individuals into the community could be achieved with quarantine periods of longer than 4.7 and 8.6 days, respectively. If rapid diagnostic testing is combined with quarantine, the lengths of quarantine to achieve 95% and 99% effectiveness could be shortened to 2.6 and 5.7 days, respectively. Sensitivity analysis revealed that quarantine alone for 8.7 days or quarantine for 5.7 days combined with using rapid diagnostic testing could prevent secondary transmissions caused by the released infectious individuals for a plausible range of prevalence at the source country (up to 10%) and for a modest number of incoming travellers (up to 8000 individuals). Quarantine at the borders of island nations could contribute substantially to preventing the arrival of pandemic influenza (or at least delaying the arrival date). For small island nations we recommend consideration of quarantine alone for 9 days or quarantine for 6 days combined with using rapid diagnostic testing (if available).

Quarantine for pandemic influenza control at the borders of small island nations

PubMed Central

2009-01-01

Background Although border quarantine is included in many influenza pandemic plans, detailed guidelines have yet to be formulated, including considerations for the optimal quarantine length. Motivated by the situation of small island nations, which will probably experience the introduction of pandemic influenza via just one airport, we examined the potential effectiveness of quarantine as a border control measure. Methods Analysing the detailed epidemiologic characteristics of influenza, the effectiveness of quarantine at the borders of islands was modelled as the relative reduction of the risk of releasing infectious individuals into the community, explicitly accounting for the presence of asymptomatic infected individuals. The potential benefit of adding the use of rapid diagnostic testing to the quarantine process was also considered. Results We predict that 95% and 99% effectiveness in preventing the release of infectious individuals into the community could be achieved with quarantine periods of longer than 4.7 and 8.6 days, respectively. If rapid diagnostic testing is combined with quarantine, the lengths of quarantine to achieve 95% and 99% effectiveness could be shortened to 2.6 and 5.7 days, respectively. Sensitivity analysis revealed that quarantine alone for 8.7 days or quarantine for 5.7 days combined with using rapid diagnostic testing could prevent secondary transmissions caused by the released infectious individuals for a plausible range of prevalence at the source country (up to 10%) and for a modest number of incoming travellers (up to 8000 individuals). Conclusion Quarantine at the borders of island nations could contribute substantially to preventing the arrival of pandemic influenza (or at least delaying the arrival date). For small island nations we recommend consideration of quarantine alone for 9 days or quarantine for 6 days combined with using rapid diagnostic testing (if available). PMID:19284571

Availability and price of malaria rapid diagnostic tests in the public and private health sectors in 2011: results from 10 nationally representative cross-sectional retail surveys.

PubMed

Poyer, Stephen; Shewchuk, Tanya; Tougher, Sarah; Ye, Yazoume; Mann, Andrea G; Willey, Barbara A; Thomson, Rebecca; Amuasi, John H; Ren, Ruilin; Wamukoya, Marilyn; Taylor, Mark; Nguah, Samuel Blay; Mberu, Blessing; Kalolella, Admirabilis; Juma, Elizabeth; Festo, Charles; Johanes, Boniface; Diap, Graciela; Bruxvoort, Katia; Ansong, Daniel; Hanson, Kara; Arnold, Fred; Goodman, Catherine

2015-06-01

To describe the state of the public and private malaria diagnostics market shortly after WHO updated its guidelines for testing all suspected malaria cases prior to treatment. Ten nationally representative cross-sectional cluster surveys were conducted in 2011 among public and private health facilities, community health workers and retail outlets (pharmacies and drug shops) in nine countries (Tanzania mainland and Zanzibar surveyed separately). Eligible outlets had antimalarials in stock on the day of interview or had stocked antimalarials in the past 3 months. Three thousand four hundred and thirty-nine rapid diagnostic test (RDT) products from 39 manufacturers were audited among 12,197 outlets interviewed. Availability was typically highest in public health facilities, although availability in these facilities varied greatly across countries, from 15% in Nigeria to >90% in Madagascar and Cambodia. Private for-profit sector availability was 46% in Cambodia, 20% in Zambia, but low in other countries. Median retail prices for RDTs in the private for-profit sector ranged from $0.00 in Madagascar to $3.13 in Zambia. The reported number of RDTs used in the 7 days before the survey in public health facilities ranged from 3 (Benin) to 50 (Zambia). Eighteen months after WHO updated its case management guidelines, RDT availability remained poor in the private sector in sub-Saharan Africa. Given the ongoing importance of the private sector as a source of fever treatment, the goal of universal diagnosis will not be achievable under current circumstances. These results constitute national baselines against which progress in scaling-up diagnostic tests can be assessed. © 2015 John Wiley & Sons Ltd.

Diagnosis of Brucellosis in Livestock and Wildlife

PubMed Central

Godfroid, Jacques; Nielsen, Klaus; Saegerman, Claude

2010-01-01

Aim To describe and discuss the merits of various direct and indirect methods applied in vitro (mainly on blood or milk) or in vivo (allergic test) for the diagnosis of brucellosis in animals. Methods The recent literature on brucellosis diagnostic tests was reviewed. These diagnostic tests are applied with different goals, such as national screening, confirmatory diagnosis, certification, and international trade. The validation of such diagnostic tests is still an issue, particularly in wildlife. The choice of the testing strategy depends on the prevailing brucellosis epidemiological situation and the goal of testing. Results Measuring the kinetics of antibody production after Brucella spp. infection is essential for analyzing serological results correctly and may help to predict abortion. Indirect ELISAs help to discriminate 1) between false positive serological reactions and true brucellosis and 2) between vaccination and infection. Biotyping of Brucella spp. provides valuable epidemiological information that allows tracing an infection back to the sources in instances where several biotypes of a given Brucella species are circulating. Polymerase chain reaction and new molecular methods are likely to be used as routine typing and fingerprinting methods in the coming years. Conclusion The diagnosis of brucellosis in livestock and wildlife is complex and serological results need to be carefully analyzed. The B. abortus S19 and B. melitensis Rev. 1 vaccines are the cornerstones of control programs in cattle and small ruminants, respectively. There is no vaccine available for pigs or for wildlife. In the absence of a human brucellosis vaccine, prevention of human brucellosis depends on the control of the disease in animals. PMID:20718082

Microwave frequency sweep interferometer for plasma density measurements in ECR ion sources: Design and preliminary results

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

Torrisi, Giuseppe; University Mediterranea of Reggio Calabria, Reggio Calabria; Mascali, David

2016-02-15

The Electron Cyclotron Resonance Ion Sources (ECRISs) development is strictly related to the availability of new diagnostic tools, as the existing ones are not adequate to such compact machines and to their plasma characteristics. Microwave interferometry is a non-invasive method for plasma diagnostics and represents the best candidate for plasma density measurement in hostile environment. Interferometry in ECRISs is a challenging task mainly due to their compact size. The typical density of ECR plasmas is in the range 10{sup 11}–10{sup 13} cm{sup −3} and it needs a probing beam wavelength of the order of few centimetres, comparable to the chambermore » radius. The paper describes the design of a microwave interferometer developed at the LNS-INFN laboratories based on the so-called “frequency sweep” method to filter out the multipath contribution in the detected signals. The measurement technique and the preliminary results (calibration) obtained during the experimental tests will be presented.« less

Characterization of spatially resolved high resolution x-ray spectrometers for HEDP and light-source experiments

NASA Astrophysics Data System (ADS)

Hill, K. W.; Bitter, M.; Delgado-Aparicio, L.; Efthimion, P.; Pablant, N.; Lu, J.; Beiersdorfer, P.; Chen, H.; Magee, E.

2014-10-01

A high resolution 1D imaging x-ray spectrometer concept comprising a spherically bent crystal and a 2D pixelated detector is being optimized for diagnostics of small sources such as high energy density physics (HEDP) and synchrotron radiation or x-ray free electron laser experiments. This instrument is used on tokamak experiments for measurement of spatial profiles of Doppler ion temperature and plasma flow velocity, as well as electron temperature. Laboratory measurements demonstrate a resolving power, E/ ΔE of 10,000 and spatial resolution better than 10 μm. Good performance is obtained for Bragg angles ranging from 23 to 63 degrees. Initial tests of the instrument on HEDP plasmas are being performed with a goal of developing spatially resolved ion and electron temperature diagnostics. This work was performed under the auspices of the US DOE by PPPL under Contract DE-AC02-09CH11466 and by LLNL under Contract DE-AC52-07NA27344.

Advanced Imaging Adds Little Value in the Diagnosis of Femoroacetabular Impingement Syndrome.

PubMed

Cunningham, Daniel J; Paranjape, Chinmay S; Harris, Joshua D; Nho, Shane J; Olson, Steven A; Mather, Richard C

2017-12-20

Femoroacetabular impingement (FAI) syndrome is an increasingly recognized source of hip pain and disability in young active adults. In order to confirm the diagnosis, providers often supplement physical examination maneuvers and radiographs with intra-articular hip injection, magnetic resonance imaging (MRI), or magnetic resonance arthrography (MRA). Since diagnostic imaging represents the fastest rising cost segment in U.S. health care, there is a need for value-driven diagnostic algorithms. The purpose of this study was to identify cost-effective diagnostic strategies for symptomatic FAI, comparing history and physical examination (H&P) alone (utilizing only radiographic imaging) with supplementation with injection, MRI, or MRA. A simple-chain decision model run as a cost-utility analysis was constructed to assess the diagnostic value of the MRI, MRA, and injection that are added to the H&P and radiographs in diagnosing symptomatic FAI. Strategies were compared using the incremental cost-utility ratio (ICUR) with a willingness to pay (WTP) of $100,000/QALY (quality-adjusted life year). Direct costs were measured using the Humana database (PearlDiver). Diagnostic test accuracy, treatment outcome probabilities, and utilities were extracted from the literature. H&P with and without supplemental diagnostic injection was the most cost-effective. Adjunct injection was preferred in situations with a WTP of >$60,000/QALY, low examination sensitivity, and high FAI prevalence. With low disease prevalence and low examination sensitivity, as may occur in a general practitioner's office, H&P with injection was the most cost-effective strategy, whereas in the reciprocal scenario, H&P with injection was only favored at exceptionally high WTP (∼$990,000). H&P and radiographs with supplemental diagnostic injection are preferred over advanced imaging, even with reasonable deviations from published values of disease prevalence, test sensitivity, and test specificity. Providers with low examination sensitivity in situations with low disease prevalence may benefit most from including injection in their diagnostic strategy. Providers with high examination sensitivity in situations with high disease prevalence may not benefit from including injection in their diagnostic strategy. Providers should not routinely rely on advanced imaging to diagnose FAI syndrome, although advanced imaging may have a role in challenging clinical scenarios. Economic and Decision Analysis Level IV. See Instructions for Authors for a complete description of levels of evidence.

42 CFR 414.508 - Payment for a new clinical diagnostic laboratory test.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 3 2010-10-01 2010-10-01 false Payment for a new clinical diagnostic laboratory... SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.508 Payment for a new clinical diagnostic laboratory test. For a new clinical diagnostic laboratory test that is assigned a new or...

20 CFR 404.1519m - Diagnostic tests or procedures.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Diagnostic tests or procedures. 404.1519m... Report Content § 404.1519m Diagnostic tests or procedures. We will request the results of any diagnostic... will not order diagnostic tests or procedures that involve significant risk to you, such as myelograms...

42 CFR 414.508 - Payment for a new clinical diagnostic laboratory test.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 3 2011-10-01 2011-10-01 false Payment for a new clinical diagnostic laboratory... SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.508 Payment for a new clinical diagnostic laboratory test. For a new clinical diagnostic laboratory test that is assigned a new or...

Wireless acquisition of multi-channel seismic data using the Seismobile system

NASA Astrophysics Data System (ADS)

Isakow, Zbigniew

2017-11-01

This paper describes the wireless acquisition of multi-channel seismic data using a specialized mobile system, Seismobile, designed for subsoil diagnostics for transportation routes. The paper presents examples of multi-channel seismic records obtained during system tests in a configuration with 96 channels (4 landstreamers of 24-channel) and various seismic sources. Seismic waves were generated at the same point using different sources: a 5-kg hammer, a Gisco's source with a 90-kg pile-driver, and two other the pile-drivers of 45 and 70 kg. Particular attention is paid to the synchronization of source timing, the measurement of geometry by autonomous GPS systems, and the repeatability of triggering measurements constrained by an accelerometer identifying the seismic waveform. The tests were designed to the registration, reliability, and range of the wireless transmission of survey signals. The effectiveness of the automatic numbering of measuring modules was tested as the system components were arranged and fixed to the streamers. After measurements were completed, the accuracy and speed of data downloading from the internal memory (SDHC 32GB WiFi) was determined. Additionally, the functionality of automatic battery recharging, the maximum survey duration, and the reliability of battery discharge signalling were assessed.

Tomographic diagnostics of nonthermal plasmas

NASA Astrophysics Data System (ADS)

Denisova, Natalia

2009-10-01

In the previous work [1], we discussed a ``technology'' of tomographic method and relations between the tomographic diagnostics in thermal (equilibrium) and nonthermal (nonequilibrium) plasma sources. The conclusion has been made that tomographic reconstruction in thermal plasma sources is the standard procedure at present, which can provide much useful information on the plasma structure and its evolution in time, while the tomographic reconstruction of nonthermal plasma has a great potential at making a contribution to understanding the fundamental problem of substance behavior in strongly nonequilibrium conditions. Using medical terminology, one could say, that tomographic diagnostics of the equilibrium plasma sources studies their ``anatomic'' structure, while reconstruction of the nonequilibrium plasma is similar to the ``physiological'' examination: it is directed to study the physical mechanisms and processes. The present work is focused on nonthermal plasma research. The tomographic diagnostics is directed to study spatial structures formed in the gas discharge plasmas under the influence of electrical and gravitational fields. The ways of plasma ``self-organization'' in changing and extreme conditions are analyzed. The analysis has been made using some examples from our practical tomographic diagnostics of nonthermal plasma sources, such as low-pressure capacitive and inductive discharges. [0pt] [1] Denisova N. Plasma diagnostics using computed tomography method // IEEE Trans. Plasma Sci. 2009 37 4 502.

Broadband Liner Optimization for the Source Diagnostic Test Fan

NASA Technical Reports Server (NTRS)

Nark, Douglas M.; Jones, Michael G.

2012-01-01

The broadband component of fan noise has grown in relevance with the utilization of increased bypass ratio and advanced fan designs. Thus, while the attenuation of fan tones remains paramount, the ability to simultaneously reduce broadband fan noise levels has become more appealing. This paper describes a broadband acoustic liner optimization study for the scale model Source Diagnostic Test fan. Specifically, in-duct attenuation predictions with a statistical fan source model are used to obtain optimum impedance spectra over a number of flow conditions for three liner locations in the bypass duct. The predicted optimum impedance information is then used with acoustic liner modeling tools to design liners aimed at producing impedance spectra that most closely match the predicted optimum values. Design selection is based on an acceptance criterion that provides the ability to apply increased weighting to specific frequencies and/or operating conditions. Typical tonal liner designs targeting single frequencies at one operating condition are first produced to provide baseline performance information. These are followed by multiple broadband design approaches culminating in a broadband liner targeting the full range of frequencies and operating conditions. The broadband liner is found to satisfy the optimum impedance objectives much better than the tonal liner designs. In addition, the broadband liner is found to provide better attenuation than the tonal designs over the full range of frequencies and operating conditions considered. Thus, the current study successfully establishes a process for the initial design and evaluation of novel broadband liner concepts for complex engine configurations.

Access to diphtheria antitoxin for therapy and diagnostics.

PubMed

Both, L; White, J; Mandal, S; Efstratiou, A

2014-06-19

The most effective treatment for diphtheria is swift administration of diphtheria antitoxin (DAT) with conjunct antibiotic therapy. DAT is an equine immunoglobulin preparation and listed among the World Health Organization Essential Medicines. Essential Medicines should be available in functioning health systems at all times in adequate amounts, in appropriate dosage forms, with assured quality, and at prices individuals and the community can afford. However, DAT is in scarce supply and frequently unavailable to patients because of discontinued production in several countries, low economic viability, and high regulatory requirements for the safe manufacture of blood-derived products. DAT is also a cornerstone of diphtheria diagnostics but several diagnostic reference laboratories across the European Union (EU) and elsewhere routinely face problems in sourcing DAT for toxigenicity testing. Overall, global access to DAT for both therapeutic and diagnostic applications seems inadequate. Therefore--besides efforts to improve the current supply of DAT--accelerated research and development of alternatives including monoclonal antibodies for therapy and molecular-based methods for diagnostics are required. Given the rarity of the disease, it would be useful to organise a small stockpile centrally for all EU countries and to maintain an inventory of DAT availability within and between countries.

Creation of a simple natural language processing tool to support an imaging utilization quality dashboard.

PubMed

Swartz, Jordan; Koziatek, Christian; Theobald, Jason; Smith, Silas; Iturrate, Eduardo

2017-05-01

Testing for venous thromboembolism (VTE) is associated with cost and risk to patients (e.g. radiation). To assess the appropriateness of imaging utilization at the provider level, it is important to know that provider's diagnostic yield (percentage of tests positive for the diagnostic entity of interest). However, determining diagnostic yield typically requires either time-consuming, manual review of radiology reports or the use of complex and/or proprietary natural language processing software. The objectives of this study were twofold: 1) to develop and implement a simple, user-configurable, and open-source natural language processing tool to classify radiology reports with high accuracy and 2) to use the results of the tool to design a provider-specific VTE imaging dashboard, consisting of both utilization rate and diagnostic yield. Two physicians reviewed a training set of 400 lower extremity ultrasound (UTZ) and computed tomography pulmonary angiogram (CTPA) reports to understand the language used in VTE-positive and VTE-negative reports. The insights from this review informed the arguments to the five modifiable parameters of the NLP tool. A validation set of 2,000 studies was then independently classified by the reviewers and by the tool; the classifications were compared and the performance of the tool was calculated. The tool was highly accurate in classifying the presence and absence of VTE for both the UTZ (sensitivity 95.7%; 95% CI 91.5-99.8, specificity 100%; 95% CI 100-100) and CTPA reports (sensitivity 97.1%; 95% CI 94.3-99.9, specificity 98.6%; 95% CI 97.8-99.4). The diagnostic yield was then calculated at the individual provider level and the imaging dashboard was created. We have created a novel NLP tool designed for users without a background in computer programming, which has been used to classify venous thromboembolism reports with a high degree of accuracy. The tool is open-source and available for download at http://iturrate.com/simpleNLP. Results obtained using this tool can be applied to enhance quality by presenting information about utilization and yield to providers via an imaging dashboard. Copyright © 2017 Elsevier B.V. All rights reserved.

X-ray transport and radiation response assessment (XTRRA) experiments at the National Ignition Facility.

PubMed

Fournier, K B; Brown, C G; Yeoman, M F; Fisher, J H; Seiler, S W; Hinshelwood, D; Compton, S; Holdener, F R; Kemp, G E; Newlander, C D; Gilliam, R P; Froula, N; Lilly, M; Davis, J F; Lerch, Maj A; Blue, B E

2016-11-01

Our team has developed an experimental platform to evaluate the x-ray-generated stress and impulse in materials. Experimental activities include x-ray source development, design of the sample mounting hardware and sensors interfaced to the National Ignition Facility's diagnostics insertion system, and system integration into the facility. This paper focuses on the X-ray Transport and Radiation Response Assessment (XTRRA) test cassettes built for these experiments. The test cassette is designed to position six samples at three predetermined distances from the source, each known to within ±1% accuracy. Built-in calorimeters give in situ measurements of the x-ray environment along the sample lines of sight. The measured accuracy of sample responses as well as planned modifications to the XTRRA cassette is discussed.

30 CFR 250.525 - What do I submit if my casing diagnostic test requires action?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What do I submit if my casing diagnostic test... if my casing diagnostic test requires action? Within 14 days after you perform a casing diagnostic... Corrective Action Plan within 30 days of the diagnostic test. (b) a casing pressure request, Regional...

Model Diagnostics for the Department of Energy's Accelerated Climate Modeling for Energy (ACME) Project

NASA Astrophysics Data System (ADS)

Smith, B.

2015-12-01

In 2014, eight Department of Energy (DOE) national laboratories, four academic institutions, one company, and the National Centre for Atmospheric Research combined forces in a project called Accelerated Climate Modeling for Energy (ACME) with the goal to speed Earth system model development for climate and energy. Over the planned 10-year span, the project will conduct simulations and modeling on DOE's most powerful high-performance computing systems at Oak Ridge, Argonne, and Lawrence Berkeley Leadership Compute Facilities. A key component of the ACME project is the development of an interactive test bed for the advanced Earth system model. Its execution infrastructure will accelerate model development and testing cycles. The ACME Workflow Group is leading the efforts to automate labor-intensive tasks, provide intelligent support for complex tasks and reduce duplication of effort through collaboration support. As part of this new workflow environment, we have created a diagnostic, metric, and intercomparison Python framework, called UVCMetrics, to aid in the testing-to-production execution of the ACME model. The framework exploits similarities among different diagnostics to compactly support diagnosis of new models. It presently focuses on atmosphere and land but is designed to support ocean and sea ice model components as well. This framework is built on top of the existing open-source software framework known as the Ultrascale Visualization Climate Data Analysis Tools (UV-CDAT). Because of its flexible framework design, scientists and modelers now can generate thousands of possible diagnostic outputs. These diagnostics can compare model runs, compare model vs. observation, or simply verify a model is physically realistic. Additional diagnostics are easily integrated into the framework, and our users have already added several. Diagnostics can be generated, viewed, and manipulated from the UV-CDAT graphical user interface, Python command line scripts and programs, and web browsers. The framework is designed to be scalable to large datasets, yet easy to use and familiar to scientists using previous tools. Integration in the ACME overall user interface facilitates data publication, further analysis, and quick feedback to model developers and scientists making component or coupled model runs.

Assessment and mitigation of diagnostic-generated electromagnetic interference at the National Ignition Facilitya)

NASA Astrophysics Data System (ADS)

Brown, C. G.; Ayers, J.; Felker, B.; Ferguson, W.; Holder, J. P.; Nagel, S. R.; Piston, K. W.; Simanovskaia, N.; Throop, A. L.; Chung, M.; Hilsabeck, T.

2012-10-01

Electromagnetic interference (EMI) is an ever-present challenge at laser facilities such as the National Ignition Facility (NIF). The major source of EMI at such facilities is laser-target interaction that can generate intense electromagnetic fields within, and outside of, the laser target chamber. In addition, the diagnostics themselves can be a source of EMI, even interfering with themselves. In this paper we describe EMI generated by ARIANE and DIXI, present measurements, and discuss effects of the diagnostic-generated EMI on ARIANE's CCD and on a PMT nearby DIXI. Finally we present some of the efforts we have made to mitigate the effects of diagnostic-generated EMI on NIF diagnostics.

A new dump system design for stray light reduction of Thomson scattering diagnostic system on EAST.

PubMed

Xiao, Shumei; Zang, Qing; Han, Xiaofeng; Wang, Tengfei; Yu, Jin; Zhao, Junyu

2016-07-01

Thomson scattering (TS) diagnostic is an important diagnostic for measuring electron temperature and density during plasma discharge. However, the measurement of Thomson scattering signal is disturbed by the stray light easily. The stray light sources in the Experimental Advanced Superconducting Tokamak (EAST) TS diagnostic system were analyzed by a simulation model of the diagnostic system, and simulation results show that the dump system is the primary stray light source. Based on the optics theory and the simulation analysis, a novel dump system including an improved beam trap was proposed and installed. The measurement results indicate that the new dump system can reduce more than 60% of the stray light for the diagnostic system, and the influence of stray light on the error of measured density decreases.

STARD 2015: An Updated List of Essential Items for Reporting Diagnostic Accuracy Studies.

PubMed

Bossuyt, Patrick M; Reitsma, Johannes B; Bruns, David E; Gatsonis, Constantine A; Glasziou, Paul P; Irwig, Les; Lijmer, Jeroen G; Moher, David; Rennie, Drummond; de Vet, Henrica C W; Kressel, Herbert Y; Rifai, Nader; Golub, Robert M; Altman, Douglas G; Hooft, Lotty; Korevaar, Daniël A; Cohen, Jérémie F

2015-12-01

Incomplete reporting has been identified as a major source of avoidable waste in biomedical research. Essential information is often not provided in study reports, impeding the identification, critical appraisal, and replication of studies. To improve the quality of reporting of diagnostic accuracy studies, the Standards for Reporting of Diagnostic Accuracy Studies (STARD) statement was developed. Here we present STARD 2015, an updated list of 30 essential items that should be included in every report of a diagnostic accuracy study. This update incorporates recent evidence about sources of bias and variability in diagnostic accuracy and is intended to facilitate the use of STARD. As such, STARD 2015 may help to improve completeness and transparency in reporting of diagnostic accuracy studies. © 2015 American Association for Clinical Chemistry.

Systematic review of the diagnosis of scabies in therapeutic trials.

PubMed

Thompson, M J; Engelman, D; Gholam, K; Fuller, L C; Steer, A C

2017-07-01

Human scabies (infestation with the mite Sarcoptes scabiei var hominis) causes a significant disease burden worldwide, yet there are no agreed diagnostic guidelines. We aimed to determine whether a consistent approach to diagnosing scabies has been used for published scabies therapeutic trials. The data sources used were the MEDLINE, Embase and Cochrane databases, from 1946 to 29 August 2013. Eligible studies were trials of therapeutic interventions against scabies in human subjects, published in English, enrolling patients with scabies, and using various therapeutic interventions. Language was a limitation of this study as some relevant trials published in languages other than English may have been excluded. Each study was reviewed by two independent authors, who assessed the clinical examination and testing approaches used for scabies diagnosis in the included studies. We found that of 71 included trials, 40 (56%) specified which clinical findings were used for diagnosis, which were predominantly rash, rash distribution, pruritus and mite burrows. Parasitological testing was used in 63% of trials (n = 45) and was used more frequently in clinic-based than in field studies. Nearly one-quarter of trials (24%, n = 17) did not define the diagnostic method used. Overall, the diagnostic approaches were poorly described, prohibiting accurate comparison of existing studies. This review further supports the need for consensus diagnostic guidelines for scabies. © 2017 British Association of Dermatologists.

Diagnosing students' misconceptions in algebra: results from an experimental pilot study.

PubMed

Russell, Michael; O'Dwyer, Laura M; Miranda, Helena

2009-05-01

Computer-based diagnostic assessment systems hold potential to help teachers identify sources of poor performance and to connect teachers and students to learning activities designed to help advance students' conceptual understandings. The present article presents findings from a study that examined how students' performance in algebra and their overcoming of common algebraic misconceptions were affected by the use of a diagnostic assessment system that focused on important algebra concepts. This study used a four-group randomized cluster trial design in which teachers were assigned randomly to one of four groups: a "business as usual" control group, a partial intervention group that was provided with access to diagnostic tests results, a partial intervention group that was provided with access to the learning activities, and a full intervention group that was given access to the test results and learning activities. Data were collected from 905 students (6th-12th grade) nested within 44 teachers. We used hierarchical linear modeling techniques to compare the effects of full, partial, and no (control) intervention on students' algebraic ability and misconceptions. The analyses indicate that full intervention had a net positive effect on ability and misconception measures.

Investigation of the boundary layer during the transition from volume to surface dominated H- production at the BATMAN test facility

NASA Astrophysics Data System (ADS)

Wimmer, C.; Schiesko, L.; Fantz, U.

2016-02-01

BATMAN (Bavarian Test Machine for Negative ions) is a test facility equipped with a 1/8 scale H- source for the ITER heating neutral beam injection. Several diagnostics in the boundary layer close to the plasma grid (first grid of the accelerator system) followed the transition from volume to surface dominated H- production starting with a Cs-free, cleaned source and subsequent evaporation of caesium, while the source has been operated at ITER relevant pressure of 0.3 Pa: Langmuir probes are used to determine the plasma potential, optical emission spectroscopy is used to follow the caesiation process, and cavity ring-down spectroscopy allows for the measurement of the H- density. The influence on the plasma during the transition from an electron-ion plasma towards an ion-ion plasma, in which negative hydrogen ions become the dominant negatively charged particle species, is seen in a strong increase of the H- density combined with a reduction of the plasma potential. A clear correlation of the extracted current densities (jH-, je) exists with the Cs emission.

Investigation of the boundary layer during the transition from volume to surface dominated H⁻ production at the BATMAN test facility.

PubMed

Wimmer, C; Schiesko, L; Fantz, U

2016-02-01

BATMAN (Bavarian Test Machine for Negative ions) is a test facility equipped with a 18 scale H(-) source for the ITER heating neutral beam injection. Several diagnostics in the boundary layer close to the plasma grid (first grid of the accelerator system) followed the transition from volume to surface dominated H(-) production starting with a Cs-free, cleaned source and subsequent evaporation of caesium, while the source has been operated at ITER relevant pressure of 0.3 Pa: Langmuir probes are used to determine the plasma potential, optical emission spectroscopy is used to follow the caesiation process, and cavity ring-down spectroscopy allows for the measurement of the H(-) density. The influence on the plasma during the transition from an electron-ion plasma towards an ion-ion plasma, in which negative hydrogen ions become the dominant negatively charged particle species, is seen in a strong increase of the H(-) density combined with a reduction of the plasma potential. A clear correlation of the extracted current densities (j(H(-)), j(e)) exists with the Cs emission.

Skin diseases associated with Malassezia species in humans. Clinical features and diagnostic criteria.

PubMed

Difonzo, E M; Faggi, E

2008-06-01

Malassezia yeasts not only cause the well known pityriasis versicolor and folliculitis, but also play an important role in other skin diseases, including seborrheic dermatitis and atopic dermatitis. The presence of Malassezia yeasts may be confirmed by direct microscopic examination and cultures of skin scrapings. In pityriasis versicolor the direct microscopic examination is the rapidest and surest test for confirming the clinical diagnosis. The preparation will show a cluster of globose budding spores with thick or double wall and short hyphae. For detecting Malassezia in the other diseases the cultures is preferable. Culture is useful both for confirming the clinical diagnosis and for epidemiological investigations. The identification of the Malassezia species is not easy. The microscopic observation of the colony direct towards the identification of Malassezia species, but it is not enough to identify the colonies definitely. Several biochemical tests are necessary for a precise identification, such as catalase reaction, growth on media without lipid sources, ability to utilize hydrophilic emulsifiers as sole lipid source, esculin test, tryptophan test.

Economic Outcomes with Anatomic versus Functional Diagnostic Testing for Coronary Artery Disease

PubMed Central

Mark, Daniel B.; Federspiel, Jerome J.; Cowper, Patricia A.; Anstrom, Kevin J.; Hoffmann, Udo; Patel, Manesh R.; Davidson-Ray, Linda; Daniels, Melanie R.; Cooper, Lawton S.; Knight, J. David; Lee, Kerry L.; Douglas, Pamela S.

2016-01-01

Background The PROMISE trial found that initial use of ≥64-slice multidetector computed tomographic angiography (CTA) versus functional diagnostic testing strategies did not improve clinical outcomes in stable symptomatic patients with suspected coronary artery disease (CAD) requiring noninvasive testing. Objective Economic analysis of PROMISE, a major secondary aim. Design Prospective economic study from the US perspective. Comparisons were made by intention-to-treat. Confidence intervals were calculated using bootstrap methods. Setting 190 U.S. centers Patients 9649 U.S. patients enrolled in PROMISE. Enrollment began July 2010 and completed September 2013. Median follow-up was 25 months. Measurements Technical costs of the initial (outpatient) testing strategy were estimated from Premier Research Database data. Hospital-based costs were estimated using hospital bills and Medicare cost-to-charge ratios. Physician fees were taken from the Medicare Fee Schedule. Costs were expressed in 2014 US dollars discounted at 3% and estimated out to 3 years using inverse probability weighting methods. Results The mean initial testing costs were: $174 for exercise ECG; $404 for CTA; $501 to $514 for (exercise, pharmacologic) stress echo; $946 to $1132 for (exercise, pharmacologic) stress nuclear. Mean costs at 90 days for the CTA strategy were $2494 versus $2240 for the functional strategy (mean difference $254, 95% CI −$634 to $906). The difference was associated with more revascularizations and catheterizations (4.25 per 100 patients) with CTA use. After 90 days, the mean cost difference between the arms out to 3 years remained small ($373). Limitations Cost weights for test strategies obtained from sources outside PROMISE. Conclusions CTA and functional diagnostic testing strategies in patients with suspected CAD have similar costs through three years of follow-up. PMID:27214597

YouTube and food allergy: An appraisal of the educational quality of information.

PubMed

Reddy, Keerthi; Kearns, Mary; Alvarez-Arango, Santiago; Carrillo-Martin, Ismael; Cuervo-Pardo, Nathaly; Cuervo-Pardo, Lyda; Dimov, Ves; Lang, David M; Lopez-Alvarez, Sonia; Schroer, Brian; Mohan, Kaushik; Dula, Mark; Zheng, Simin; Kozinetz, Claudia; Gonzalez-Estrada, Alexei

2018-06-01

Food allergy affects an estimated 8% of children and 3% of adults in the United States. Food-allergic individuals increasingly use the web for medical information. We sought to determine the educational quality of food allergy YouTube videos. We performed a YouTube search using keywords "food allergy" and "food allergies". The 300 most viewed videos were included and analyzed for characteristics, source, and content. Source was further classified as healthcare provider, alternative medicine provider, patient, company, media, and professional society. A scoring system (FA-DQS) was created to evaluate quality (-10 to +34 points). Negative points were assigned for misleading information. Eight reviewers scored each video independently. Three hundred videos were analyzed, with a median of 6351.50 views, 19 likes, and 1 dislike. More video presenters were female (54.3%). The most common type of video source was alternative medicine provider (26.3%). Alternative treatments included the following: water fast, juicing, Ayurveda, apple cider, yoga, visualization, and sea moss. Controversial diagnostics included kinesiology, IgG testing, and pulse test. Almost half of the videos depicted a non-IgE-mediated reaction (49.0%).Videos by professional societies had the highest FA-DQS (7.27). Scores for videos by professional societies were significantly different from other sources (P < .001). There was a high degree of agreement among reviewers (ICC = 0.820; P < .001). YouTube videos on food allergy frequently recommend controversial diagnostics and commonly depict non-IgE-mediated reactions. There is a need for high-quality, evidence-based, educational videos on food allergy. © 2018 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

Fan Noise Source Diagnostic Test: Vane Unsteady Pressure Results

NASA Technical Reports Server (NTRS)

Envia, Edmane

2002-01-01

To investigate the nature of fan outlet guide vane pressure fluctuations and their link to rotor-stator interaction noise, time histories of vane fluctuating pressures were digitally acquired as part of the Fan Noise Source Diagnostic Test. Vane unsteady pressures were measured at seven fan tip speeds for both a radial and a swept vane configuration. Using time-domain averaging and spectral analysis, the blade passing frequency (BPF) harmonic and broadband contents of the vane pressures were individually analyzed. Significant Sound Pressure Level (SPL) reductions were observed for the swept vane relative to the radial vane for the BPF harmonics of vane pressure, but vane broadband reductions due to sweep turned out to be much smaller especially on an average basis. Cross-correlation analysis was used to establish the level of spatial coherence of broadband pressures between different locations on the vane and integral length scales of pressure fluctuations were estimated from these correlations. Two main results of this work are: (1) the average broadband level on the vane (in dB) increases linearly with the fan tip speed for both the radial and swept vanes, and (2) the broadband pressure distribution on the vane is nearly homogeneous and its integral length scale is a monotonically decreasing function of fan tip speed.

40 CFR 85.2222 - On-board diagnostic test procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 19 2013-07-01 2013-07-01 false On-board diagnostic test procedures... Warranty Short Tests § 85.2222 On-board diagnostic test procedures. The test sequence for the inspection of on-board diagnostic systems on 1996 and newer light-duty vehicles and light-duty trucks shall consist...

40 CFR 85.2222 - On-board diagnostic test procedures.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 19 2012-07-01 2012-07-01 false On-board diagnostic test procedures... Warranty Short Tests § 85.2222 On-board diagnostic test procedures. The test sequence for the inspection of on-board diagnostic systems on 1996 and newer light-duty vehicles and light-duty trucks shall consist...

40 CFR 85.2231 - On-board diagnostic test equipment requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 19 2012-07-01 2012-07-01 false On-board diagnostic test equipment... Warranty Short Tests § 85.2231 On-board diagnostic test equipment requirements. (a) The test system interface to the vehicle shall include a plug that conforms to SAE J1962 “Diagnostic Connector.” The...

40 CFR 85.2222 - On-board diagnostic test procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 18 2011-07-01 2011-07-01 false On-board diagnostic test procedures... Warranty Short Tests § 85.2222 On-board diagnostic test procedures. The test sequence for the inspection of on-board diagnostic systems on 1996 and newer light-duty vehicles and light-duty trucks shall consist...

40 CFR 85.2231 - On-board diagnostic test equipment requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 18 2011-07-01 2011-07-01 false On-board diagnostic test equipment... Warranty Short Tests § 85.2231 On-board diagnostic test equipment requirements. (a) The test system interface to the vehicle shall include a plug that conforms to SAE J1962 “Diagnostic Connector.” The...

40 CFR 85.2231 - On-board diagnostic test equipment requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 19 2013-07-01 2013-07-01 false On-board diagnostic test equipment... Warranty Short Tests § 85.2231 On-board diagnostic test equipment requirements. (a) The test system interface to the vehicle shall include a plug that conforms to SAE J1962 “Diagnostic Connector.” The...

The Daniel K. Inouye College of Pharmacy Scripts: Updates on Clostridium difficile Infection: Advances in Laboratory Testing to Aid Diagnosis and Treatment.

PubMed

Lteif, Louis

2017-02-01

Clostridium difficile remains a major source of nosocomial infections and associated diarrhea. More recently, community-acquired cases are on the rise creating a concern for a serious public health threat. Appropriate infection control precautions as well as prevention and optimal management may help to avoid detrimental outbreaks. A key step is utilizing laboratory testing for quick and accurate diagnosis of potential cases. This overview article describes Clostridium difficile infection control and prevention methods and updates the most recent management strategies including a focus on the utilization and interpretation of laboratory diagnostic testing and appropriate treatment.

A compact time-of-flight mass spectrometer for ion source characterization

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

Chen, L., E-mail: l.chen03@gmail.com; Wan, X.; Jin, D. Z.

2015-03-15

A compact time-of-flight mass spectrometer with overall dimension of about 413 × 250 × 414 mm based on orthogonal injection and angle reflection has been developed for ion source characterization. Configuration and principle of the time-of-flight mass spectrometer are introduced in this paper. The mass resolution is optimized to be about 1690 (FWHM), and the ion energy detection range is tested to be between about 3 and 163 eV with the help of electron impact ion source. High mass resolution and compact configuration make this spectrometer useful to provide a valuable diagnostic for ion spectra fundamental research and study themore » mass to charge composition of plasma with wide range of parameters.« less

30-lens interferometer for high energy x-rays

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

Lyubomirskiy, M., E-mail: lyubomir@esrf.fr; Snigireva, I., E-mail: irina@esrf.fr; Vaughan, G.

2016-07-27

We report a hard X-ray multilens interferometer consisting of 30 parallel compound refractive lenses. Under coherent illumination each CRL creates a diffraction limited focal spot - secondary source. An overlapping of coherent beams from these sources resulting in the interference pattern which has a rich longitudinal structure in accordance with the Talbot imaging formalism. The proposed interferometer was experimentally tested at ID11 ESRF beamline for the photon energies 32 keV and 65 keV. The fundamental and fractional Talbot images were recorded with the high resolution CCD camera. An effective source size in the order of 15 µm was determined frommore » the first Talbot image proving that the multilens interferometer can be used as a high resolution beam diagnostic tool.« less

Diagnostic Air Quality Model Evaluation of Source-Specific Primary and Secondary Fine Particulate Carbon

EPA Science Inventory

Ambient measurements of 78 source-specific tracers of primary and secondary carbonaceous fine particulate matter collected at four midwestern United States locations over a full year (March 2004–February 2005) provided an unprecedented opportunity to diagnostically evaluate...

Comparison of Far-Field Noise for Three Significantly Different Model Turbofans

NASA Technical Reports Server (NTRS)

Woodward, Richard P.

2008-01-01

Far-field noise sound power level (PWL) spectra and overall sound pressure level (OASPL) directivities were compared for three significantly different model fan stages which were tested in the NASA Glenn 9x15 Low Speed Wind Tunnel. The test fans included the Advanced Ducted Propulsor (ADP) Fan1, the baseline Source Diagnostic Test (SDT) fan, and the Quiet High Speed Fan2 (QHSF2) These fans had design rotor tangential tip speeds from 840 to 1474 ft/s and stage pressure ratios from 1.29 to 1.82. Additional parameters included rotor-stator spacing, stator sweep, and downstream support struts. Acoustic comparison points were selected on the basis of stage thrust. Acoustic results for the low tip speed/low pressure ratio fan (ADP Fan1) were thrust-adjusted to show how a geometrically-scaled version of this fan might compare at the higher design thrust levels of the other two fans. Lowest noise levels were typically observed for ADP Fan1 (which had a radial stator) and for the intermediate tip speed fan (Source Diagnostics Test, SDT, R4 rotor) with a swept stator. Projected noise levels for the ADP fan to the SDT swept stator configuration at design point conditions showed the fans to have similar noise levels. However, it is possible that the ADP fan could be 2 to 3 dB quieter with incorporation of a swept stator. Benefits of a scaled ADP fan include avoidance of multiple pure tones associated with transonic and higher blade tip speeds. Penalties of a larger size ADP fan would include increased nacelle size and drag.

Comparison of Far-field Noise for Three Significantly Different Model Turbofans

NASA Technical Reports Server (NTRS)

Woodward, Richard P.

2008-01-01

Far-field noise sound power level (PWL) spectra and overall sound pressure level (OASPL) directivities were compared for three significantly different model fan stages which were tested in the NASA Glenn 9 15 Low Speed Wind Tunnel. The test fans included the Advanced Ducted Propulsor (ADP) Fan1, the baseline Source Diagnostic Test (SDT) fan, and the Quiet High Speed Fan2 (QHSF2). These fans had design rotor tangential tip speeds from 840 to 1474 ft/s and stage pressure ratios from 1.29 to 1.82. Additional parameters included rotor-stator spacing, stator sweep, and downstream support struts. Acoustic comparison points were selected on the basis of stage thrust. Acoustic results for the low tip speed/low pressure ratio fan (ADP Fan1) were thrust-adjusted to show how a geometrically-scaled version of this fan might compare at the higher design thrust levels of the other two fans. Lowest noise levels were typically observed for ADP Fan1 (which had a radial stator) and for the intermediate tip speed fan (Source Diagnostics Test, SDT, R4 rotor) with a swept stator. Projected noise levels for the ADP fan to the SDT swept stator configuration at design point conditions showed the fans to have similar noise levels. However, it is possible that the ADP fan could be 2 to 3 dB quieter with incorporation of a swept stator. Benefits of a scaled ADP fan include avoidance of multiple pure tones associated with transonic and higher blade tip speeds. Penalties of a larger size ADP fan would include increased nacelle size and drag.

The Quantitative Science of Evaluating Imaging Evidence.

PubMed

Genders, Tessa S S; Ferket, Bart S; Hunink, M G Myriam

2017-03-01

Cardiovascular diagnostic imaging tests are increasingly used in everyday clinical practice, but are often imperfect, just like any other diagnostic test. The performance of a cardiovascular diagnostic imaging test is usually expressed in terms of sensitivity and specificity compared with the reference standard (gold standard) for diagnosing the disease. However, evidence-based application of a diagnostic test also requires knowledge about the pre-test probability of disease, the benefit of making a correct diagnosis, the harm caused by false-positive imaging test results, and potential adverse effects of performing the test itself. To assist in clinical decision making regarding appropriate use of cardiovascular diagnostic imaging tests, we reviewed quantitative concepts related to diagnostic performance (e.g., sensitivity, specificity, predictive values, likelihood ratios), as well as possible biases and solutions in diagnostic performance studies, Bayesian principles, and the threshold approach to decision making. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Evaluating Diagnostic Point-of-Care Tests in Resource-Limited Settings

PubMed Central

Drain, Paul K; Hyle, Emily P; Noubary, Farzad; Freedberg, Kenneth A; Wilson, Douglas; Bishai, William; Rodriguez, William; Bassett, Ingrid V

2014-01-01

Diagnostic point-of-care (POC) testing is intended to minimize the time to obtain a test result, thereby allowing clinicians and patients to make an expeditious clinical decision. As POC tests expand into resource-limited settings (RLS), the benefits must outweigh the costs. To optimize POC testing in RLS, diagnostic POC tests need rigorous evaluations focused on relevant clinical outcomes and operational costs, which differ from evaluations of conventional diagnostic tests. Here, we reviewed published studies on POC testing in RLS, and found no clearly defined metric for the clinical utility of POC testing. Therefore, we propose a framework for evaluating POC tests, and suggest and define the term “test efficacy” to describe a diagnostic test’s capacity to support a clinical decision within its operational context. We also proposed revised criteria for an ideal diagnostic POC test in resource-limited settings. Through systematic evaluations, comparisons between centralized diagnostic testing and novel POC technologies can be more formalized, and health officials can better determine which POC technologies represent valuable additions to their clinical programs. PMID:24332389

[Diagnostic test scale SI5: Assessment of sacroiliac joint dysfunction].

PubMed

Acevedo González, Juan C; Quintero Oliveros, Silvia

2015-01-01

Sacroiliac joint dysfunction is a known cause of low back pain. We think that a diagnostic score scale (SI5) may be performed to assess diagnostic utility of clinical signs of sacroiliac joint dysfunction. The primary aim of the present study was to conduct the pilot study of our new diagnostic score scale, the SI5, for sacroiliac joint syndrome. We reviewed the literature on clinical characteristics, diagnostic tests and imaging most commonly used in diagnosing sacroiliac joint dysfunction. Our group evaluated the diagnostic utility of these aspects and we used those considered most representative to develop the SI5 diagnostic scale. The SI5 scale was applied to 22 patients with low back pain; afterwards, the standard test for diagnosing this pathology (selective blockage of the SI joint) was also performed on these patients. The sensitivity and specificity for each sign were also assessed and the diagnostic scale called SI5 was then proposed, based on these data. The most sensitive clinical tests for diagnosing SI joint dysfunction were 2 patient-reported clinical characteristics, the Laguerre Test, sacroiliac rocking test and Yeomans test (greater than 80% sensitivity). The tests with greatest diagnostic specificity (>80%) were the Lewitt test, Piedallu test and Gillet test. The proposed SI5 test score scale showed sensitivity of 73% and specificity of 71%. Sacroiliac joint syndrome has been shown to produce low back pain frequently; however, the diagnostic value of examination tests for sacroiliac joint pain has been questioned by other authors. The pilot study on the SI5 diagnostic score scale showed good sensitivity and specificity. However, the process of statistical validation of the SI5 needs to be continued. Copyright © 2014 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

Epidemiology, diagnostics, and management of tuberculosis in domestic cattle and deer in New Zealand in the face of a wildlife reservoir.

PubMed

Buddle, B M; de Lisle, G W; Griffin, J F T; Hutchings, S A

2015-06-01

The control of tuberculosis (TB) in cattle and farmed deer in New Zealand has been greatly influenced by the existence of a wildlife reservoir of Mycobacterium bovis infection, principally the Australian brushtail possum (Trichosurus vulpecula). The reduction in possum numbers in areas with endemic M. bovis infection through vigorous vector control operations has been a major contributor to the marked reduction in the number of infected cattle and farmed deer herds in the past two decades. Management of TB in cattle and farmed deer in New Zealand has involved a combination of vector control, regionalisation of diagnostic testing of cattle and deer herds, abattoir surveillance and movement control from vector risk areas. Accurate diagnosis of infected cattle and deer has been a crucial component in the control programme. As the control programme has evolved, test requirements have changed and new tests have been introduced or test interpretations modified. Subspecific strain typing of M. bovis isolates has proved to be a valuable component in the epidemiological investigation of herd breakdowns to identify whether the source of infection was domestic livestock or wildlife. New initiatives will include the use of improved models for analysing diagnostic test data and characterising disease outbreaks leading to faster elimination of infection from herds. The introduction of the National Animal Identification Tracing programme will allow better risk profiling of individual herds and more reliable tracing of animal movements. TB in cattle and farmed deer in New Zealand can only be controlled by eliminating the disease in both domestic livestock and the wildlife reservoir.

International External Quality Assurance for Laboratory Diagnosis of Diphtheria ▿

PubMed Central

Neal, S. E.; Efstratiou, A.

2009-01-01

The diphtheria surveillance network (DIPNET) encompassing National Diphtheria Reference Centers from 25 European countries is a Dedicated Surveillance Network recognized by the European Commission. A key DIPNET objective is the quality assessment of microbiological procedures for diphtheria across the European Union and beyond. A detailed questionnaire on the level of reference laboratory services and an external quality assessment (EQA) panel comprising six simulated throat specimens were sent to 34 centers. Twenty-three centers are designated National Diphtheria Reference Centers, with the laboratory in the United Kingdom being the only WHO Collaborating Centre. A variety of screening and identification tests were used, including the cysteinase test (20/34 centers), pyrazinamidase test (17/34 centers), and commercial kits (25/34 centers). The classic Elek test for toxigenicity testing is mostly used (28/34 centers), with variations in serum sources and antitoxin concentrations. Many laboratories reported problems obtaining Elek reagents or media. Only six centers produced acceptable results for all six specimens. Overall, 21% of identification and 13% of toxigenicity reports were unacceptable. Many centers could not isolate the target organism, and most found difficulties with the specimens that contained Corynebacterium striatum as a commensal contaminant. Nineteen centers generated either false-positive or negative toxigenic results, which may have caused inappropriate medical management. The discrepancies in this diphtheria diagnostics EQA alarmingly reflect the urgent need to improve laboratory performance in diphtheria diagnostics in Europe, standardize feasible and robust microbiological methods, and build awareness among public health authorities. Therefore, DIPNET recommends that regular workshops and EQA distributions for diphtheria diagnostics should be supported and maintained. PMID:19828749

How to Use the DX SYSTEM of Diagnostic Testing. Methodology Project.

ERIC Educational Resources Information Center

McArthur, David; Cabello, Beverly

The DX SYSTEM of Diagnostic Testing is an easy-to-use computerized system for developing and administering diagnostic tests. A diagnostic test measures a student's mastery of a specific domain (skill or content area). It examines the necessary subskills hierarchically from the most to the least complex. The DX SYSTEM features tailored testing with…

Measures of accuracy and performance of diagnostic tests.

PubMed

Drobatz, Kenneth J

2009-05-01

Diagnostic tests are integral to the practice of veterinary cardiology, any other specialty, and general veterinary medicine. Developing and understanding diagnostic tests is one of the cornerstones of clinical research. This manuscript describes the diagnostic test properties including sensitivity, specificity, predictive value, likelihood ratio, receiver operating characteristic curve. Review of practical book chapters and standard statistics manuscripts. Diagnostics such as sensitivity, specificity, predictive value, likelihood ratio, and receiver operating characteristic curve are described and illustrated. Basic understanding of how diagnostic tests are developed and interpreted is essential in reviewing clinical scientific papers and understanding evidence based medicine.

42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... Nonphysician practitioners (that is, clinical nurse specialists, clinical psychologists, clinical social... that do not involve the use of contrast media; and (iii) Diagnostic mammograms if the approved portable...

What Do Diagnostic Reading Tests Really Diagnose?

ERIC Educational Resources Information Center

Winkley, Carol K.

A study was made of nine reading tests, including both group and individually-administered measures, which are claimed to be chiefly diagnostic. Instruments analyzed were the following: Silent Reading Diagnostic Tests (Bond, Balow, and Hoyt), Botel Reading Inventory, Durrell Analysis of Reading Difficulty, Gates-McKillop Reading Diagnostic Tests,…

9 CFR 93.404 - Import permits for ruminants and for ruminant test specimens for diagnostic purposes; and...

Code of Federal Regulations, 2012 CFR

2012-01-01

... ruminant test specimens for diagnostic purposes; and reservation fees for space at quarantine facilities... for ruminants and for ruminant test specimens for diagnostic purposes; and reservation fees for space...) For ruminants and ruminant test specimens for diagnostic screening purposes intended for importation...

9 CFR 93.404 - Import permits for ruminants and for ruminant test specimens for diagnostic purposes; and...

Code of Federal Regulations, 2013 CFR

2013-01-01

... ruminant test specimens for diagnostic purposes; and reservation fees for space at quarantine facilities... for ruminants and for ruminant test specimens for diagnostic purposes; and reservation fees for space...) For ruminants and ruminant test specimens for diagnostic screening purposes intended for importation...

9 CFR 93.404 - Import permits for ruminants and for ruminant test specimens for diagnostic purposes; and...

Code of Federal Regulations, 2014 CFR

2014-01-01

... ruminant test specimens for diagnostic purposes; and reservation fees for space at quarantine facilities... for ruminants and for ruminant test specimens for diagnostic purposes; and reservation fees for space...) For ruminants and ruminant test specimens for diagnostic screening purposes intended for importation...

9 CFR 93.404 - Import permits for ruminants and for ruminant test specimens for diagnostic purposes; and...

Code of Federal Regulations, 2010 CFR

2010-01-01

... ruminant test specimens for diagnostic purposes; and reservation fees for space at quarantine facilities... for ruminants and for ruminant test specimens for diagnostic purposes; and reservation fees for space...) For ruminants and ruminant test specimens for diagnostic screening purposes intended for importation...

9 CFR 93.404 - Import permits for ruminants and for ruminant test specimens for diagnostic purposes; and...

Code of Federal Regulations, 2011 CFR

2011-01-01

... ruminant test specimens for diagnostic purposes; and reservation fees for space at quarantine facilities... for ruminants and for ruminant test specimens for diagnostic purposes; and reservation fees for space...) For ruminants and ruminant test specimens for diagnostic screening purposes intended for importation...

Uptake of prenatal diagnostic testing and the effectiveness of prenatal screening for Down syndrome.

PubMed

Jaques, Alice M; Collins, Veronica R; Muggli, Evelyne E; Amor, David J; Francis, Ivan; Sheffield, Leslie J; Halliday, Jane L

2010-06-01

To map prenatal screening and diagnostic testing pathways in Victorian pregnant women during 2003 to 2004; measure the impact of prenatal diagnostic testing uptake on the effectiveness of prenatal screening for Down syndrome; and assess factors influencing uptake of diagnostic testing following screening. State-wide data collections of prenatal screening and diagnostic tests were linked to all Victorian births and pregnancy terminations for birth defects. Overall, 52% of women had a prenatal test (65 692/126 305); screening (44.9%), diagnostic testing (3.9%), or both (3.2%). Uptake of diagnostic testing was 71.4% (2390/3349) after an increased risk screen result, and 2.5% (1381/54 286) after a low risk result. Variation in uptake of diagnostic testing reduced the effectiveness of the screening program by 11.2%: from 87.4% (sensitivity - 125/143) to 76.2% (prenatal diagnoses of Down syndrome - 109/143). In both the increased and low risk groups, uptake was influenced by absolute numerical risk, as well as by the change in numerical risk from a priori risk. This comprehensive follow-up demonstrates clearly that numerical risk is being used to aid in decision making about confirmatory diagnostic testing. Collectively, these fundamental individual decisions will impact on the overall effectiveness of screening programmes for Down syndrome.

A new dump system design for stray light reduction of Thomson scattering diagnostic system on EAST

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

Xiao, Shumei; Zang, Qing, E-mail: zangq@ipp.ac.cn; Han, Xiaofeng

Thomson scattering (TS) diagnostic is an important diagnostic for measuring electron temperature and density during plasma discharge. However, the measurement of Thomson scattering signal is disturbed by the stray light easily. The stray light sources in the Experimental Advanced Superconducting Tokamak (EAST) TS diagnostic system were analyzed by a simulation model of the diagnostic system, and simulation results show that the dump system is the primary stray light source. Based on the optics theory and the simulation analysis, a novel dump system including an improved beam trap was proposed and installed. The measurement results indicate that the new dump systemmore » can reduce more than 60% of the stray light for the diagnostic system, and the influence of stray light on the error of measured density decreases.« less

Identifying a Robust and Practical Quasar Accretion-Rate Indicator Using the Chandra Archive

NASA Astrophysics Data System (ADS)

Shemmer, Ohad

2017-09-01

Understanding the rapid growth of supermassive black holes and the assembly of their host galaxies is severely limited by the lack of reliable estimates of black-hole mass and accretion rate in distant quasars. We propose to utilize the Chandra archive to identify the most reliable and practical Eddington-ratio indicator by investigating diagnostics of quasar accretion power in the hard-X-ray, C IV, and Hbeta spectral bands of a carefully-selected sample of optically-selected sources. We will perform a ``stress test'' to each of these diagnostics, relying critically on the hard-X-ray observable properties, and deliver a prescription for the most robust Eddington-ratio estimate that can be utilized economically at the highest accessible redshifts.

Identification of antigenic Sarcoptes scabiei proteins for use in a diagnostic test and of non-antigenic proteins that may be immunomodulatory

PubMed Central

Morgan, Marjorie S.; Rider, S. Dean; Arlian, Larry G.

2017-01-01

Background Scabies, caused by the mite, Sarcoptes scabiei, infects millions of humans, and many wild and domestic mammals. Scabies mites burrow in the lower stratum corneum of the epidermis of the skin and are the source of substances that are antigenic or modulate aspects of the protective response of the host. Ordinary scabies is a difficult disease to diagnose. Objective The goal of this project was to identify S. scabiei proteins that may be candidate antigens for use in a diagnostic test or may be used by the mite to modulate the host’s protective response. Methods An aqueous extract of S. scabiei was separated by 2-dimensional electrophoresis and proteins were identified by mass spectrometry. A parallel immunoblot was probed with serum from patients with ordinary scabies to identify IgM and/or IgG-binding antigens. The genes coding for 23 selected proteins were cloned into E. coli and the expressed recombinant proteins were screened with serum from patients with confirmed ordinary scabies. Results We identified 50 different proteins produced by S. scabiei, 34 of which were not previously identified, and determined that 66% were recognized by patient IgM and/or IgG. Fourteen proteins were screened for use in a diagnostic test but none possessed enough sensitivity and specificity to be useful. Six of the 9 proteins selected for the possibility that they may be immunomodulatory were not recognized by antibodies in patient serum. Conclusions Thirty-three proteins that bound IgM and/or IgG from the serum of patients with ordinary scabies were identified. None of the 14 tested were useful for inclusion in a diagnostic test. The identities of 16 proteins that are not recognized as antigens by infected patients were also determined. These could be among the molecules that are responsible for this mite’s ability to modulate its host’s innate and adaptive immune responses. PMID:28604804

Assessment and Mitigation of Diagnostic-Generated Electromagnetic Interference at the National Ignition Facility

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

Brown, C G; Ayers, M J; Felker, B

2012-04-20

Electromagnetic interference (EMI) is an ever-present challenge at laser facilities such as the National Ignition Facility (NIF). The major source of EMI at such facilities is laser-target interaction that can generate intense electromagnetic fields within, and outside of, the laser target chamber. In addition, the diagnostics themselves can be a source of EMI, even interfering with themselves. In this paper we describe EMI generated by ARIANE and DIXI, present measurements, and discuss effects of the diagnostic-generated EMI on ARIANE's CCD and on a PMT nearby DIXI. Finally we present some of the efforts we have made to mitigate the effectsmore » of diagnostic-generated EMI on NIF diagnostics.« less

Preliminary assessment of the diagnostic performances of a new rapid diagnostic test for the serodiagnosis of human cystic echinococcosis.

PubMed

Vola, Ambra; Tamarozzi, Francesca; Noordin, Rahmah; Yunus, Muhammad Hafiznur; Khanbabaie, Sam; De Silvestri, Annalisa; Brunetti, Enrico; Mariconti, Mara

2018-04-14

Rapid diagnostic tests for cystic echinococcosis (CE) are convenient to support ultrasound diagnosis in uncertain cases, especially in resource-limited settings. We found comparable diagnostic performances of the experimental Hyd Rapid Test and the commercial VIRapid HYDATIDOSIS Test, used in our diagnostic laboratory, using samples from well-characterized hepatic CE cases. Copyright © 2018 Elsevier Inc. All rights reserved.

Management of chronic low back pain: rationales, principles, and targets of imaging-guided spinal injections.

PubMed

Fritz, Jan; Niemeyer, Thomas; Clasen, Stephan; Wiskirchen, Jakub; Tepe, Gunnar; Kastler, Bruno; Nägele, Thomas; König, Claudius W; Claussen, Claus D; Pereira, Philippe L

2007-01-01

If low back pain does not improve with conservative management, the cause of the pain must be determined before further therapy is initiated. Information obtained from the patient's medical history, physical examination, and imaging may suffice to rule out many common causes of chronic pain (eg, fracture, malignancy, visceral or metabolic abnormality, deformity, inflammation, and infection). However, in most cases, the initial clinical and imaging findings have a low predictive value for the identification of specific pain-producing spinal structures. Diagnostic spinal injections performed in conjunction with imaging may be necessary to test the hypothesis that a particular structure is the source of pain. To ensure a valid test result, diagnostic injection procedures should be monitored with fluoroscopy, computed tomography, or magnetic resonance imaging. The use of controlled and comparative injections helps maximize the reliability of the test results. After a symptomatic structure has been identified, therapeutic spinal injections may be administered as an adjunct to conservative management, especially in patients with inoperable conditions. Therapeutic injections also may help hasten the recovery of patients with persistent or recurrent pain after spinal surgery. RSNA, 2007

The Effect of Bypass Nozzle Exit Area on Fan Aerodynamic Performance and Noise in a Model Turbofan Simulator

NASA Technical Reports Server (NTRS)

Hughes, Christopher E.; Podboy, Gary, G.; Woodward, Richard P.; Jeracki, Robert, J.

2013-01-01

The design of effective new technologies to reduce aircraft propulsion noise is dependent on identifying and understanding the noise sources and noise generation mechanisms in the modern turbofan engine, as well as determining their contribution to the overall aircraft noise signature. Therefore, a comprehensive aeroacoustic wind tunnel test program was conducted called the Fan Broadband Source Diagnostic Test as part of the NASA Quiet Aircraft Technology program. The test was performed in the anechoic NASA Glenn 9- by 15-Foot Low Speed Wind Tunnel using a 1/5 scale model turbofan simulator which represented a current generation, medium pressure ratio, high bypass turbofan aircraft engine. The investigation focused on simulating in model scale only the bypass section of the turbofan engine. The test objectives were to: identify the noise sources within the model and determine their noise level; investigate several component design technologies by determining their impact on the aerodynamic and acoustic performance of the fan stage; and conduct detailed flow diagnostics within the fan flow field to characterize the physics of the noise generation mechanisms in a turbofan model. This report discusses results obtained for one aspect of the Source Diagnostic Test that investigated the effect of the bypass or fan nozzle exit area on the bypass stage aerodynamic performance, specifically the fan and outlet guide vanes or stators, as well as the farfield acoustic noise level. The aerodynamic performance, farfield acoustics, and Laser Doppler Velocimeter flow diagnostic results are presented for the fan and four different fixed-area bypass nozzle configurations. The nozzles simulated fixed engine operating lines and encompassed the fan stage operating envelope from near stall to cruise. One nozzle was selected as a baseline reference, representing the nozzle area which would achieve the design point operating conditions and fan stage performance. The total area change from the smallest to the largest nozzle was 12.9 percent of the baseline nozzle area. The results will show that there are significant changes in aerodynamic performance and farfield acoustics as the fan nozzle area is increased. The weight flow through the fan model increased between 7 and 9 percent, the fan and stage pressure dropped between 8 and 10 percent, and the adiabatic efficiency increased between 2 and 3 percent--the magnitude of the change dependent on the fan speed. Results from force balance measurements of fan and outlet guide vane thrust will show that as the nozzle exit area is increased the combined thrust of the fan and outlet guide vanes together also increases, between 2 and 3.5 percent, mainly due to the increase in lift from the outlet guide vanes. In terms of farfield acoustics, the overall sound power level produced by the fan stage dropped nearly linearly between 1 dB at takeoff condition and 3.5 dB at approach condition, mainly due to a decrease in the broadband noise levels. Finally, fan swirl angle survey and Laser Doppler Velocimeter mean velocity and turbulence data obtained in the fan wake will show that the swirl angles and turbulence levels within the wake decrease as the fan nozzle area increases, which helps to explain the drop in the fan broadband noise at all fan speeds.

Posterior, Lateral, and Anterior Hip Pain Due to Musculoskeletal Origin: A Narrative Literature Review of History, Physical Examination, and Diagnostic Imaging.

PubMed

Battaglia, Patrick J; D'Angelo, Kevin; Kettner, Norman W

2016-12-01

The purpose of this study was to present a narrative review of the literature of musculoskeletal causes of adult hip pain, with special attention to history, physical examination, and diagnostic imaging. A narrative review of the English medical literature was performed by using the search terms "hip pain" AND "anterior," "lateral," and "posterior." Additionally, specific entities of hip pain or pain referral sources to the hip were searched for. We used the PubMed search engine through January 15, 2016. Musculoskeletal sources of adult hip pain can be divided into posterior, lateral, and anterior categories. For posterior hip pain, select considerations include lumbar spine and femoroacetabular joint referral, sacroiliac joint pathology, piriformis syndrome, and proximal hamstring tendinopathy. Gluteal tendinopathy and iliotibial band thickening are the most common causes of lateral hip pain. Anterior hip pain is further divided into causes that are intra-articular (ie, labral tear, osteoarthritis, osteonecrosis) and extra-articular (ie, snapping hip and inguinal disruption [athletic pubalgia]). Entrapment neuropathies and myofascial pain should also be considered in each compartment. A limited number of historical features and physical examination tests for evaluation of adult hip pain are supported by the literature and are discussed in this article. Depending on the clinical differential, the gamut of diagnostic imaging modalities recommended for accurate diagnosis include plain film radiography, computed tomography, magnetic resonance imaging, skeletal scintigraphy, and ultrasonography. The evaluation of adult hip pain is challenging. Clinicians should consider posterior, lateral, and anterior sources of pain while keeping in mind that these may overlap.

Identifying Students' Mathematical Skills from a Multiple-Choice Diagnostic Test Using an Iterative Technique to Minimise False Positives

ERIC Educational Resources Information Center

Manning, S.; Dix, A.

2008-01-01

There is anecdotal evidence that a significant number of students studying computing related courses at degree level have difficulty with sub-GCE mathematics. Testing of students' skills is often performed using diagnostic tests and a number of computer-based diagnostic tests exist, which work, essentially, by testing one specific diagnostic skill…

Non-destructive diagnostics of irradiated materials using neutron scattering from pulsed neutron sources

NASA Astrophysics Data System (ADS)

Korenev, Sergey; Sikolenko, Vadim

2004-09-01

The advantage of neutron-scattering studies as compared to the standard X-ray technique is the high penetration of neutrons that allow us to study volume effects. The high resolution of instrumentation on the basis neutron scattering allows measurement of the parameters of lattice structure with high precision. We suggest the use of neutron scattering from pulsed neutron sources for analysis of materials irradiated with pulsed high current electron and ion beams. The results of preliminary tests using this method for Ni foils that have been studied by neutron diffraction at the IBR-2 (Pulsed Fast Reactor at Joint Institute for Nuclear Research) are presented.

An alternate approach to the production of radioisotopes for nuclear medicine applications

NASA Astrophysics Data System (ADS)

D'Auria, John M.; Keller, Roderich; Ladouceur, Keith; Lapi, Suzanne E.; Ruth, Thomas J.; Schmor, Paul

2013-03-01

There is a growing need for the production of radioisotopes for both diagnostic and therapeutic medical applications. Radioisotopes that are produced using the (n,γ) or (γ,n) reactions, however, typically result in samples with low specific activity (radioactivity/gram) due to the high abundance of target material of the same element. One method to effectively remove the isotopic impurity is electro-magnetic mass separation. An Ion Source Test Facility has been constructed at TRIUMF to develop high-intensity, high-efficiency, reliable ion sources for purification of radioactive isotopes, particularly those used in nuclear medicine. In progress studies are presented.

An alternate approach to the production of radioisotopes for nuclear medicine applications.

PubMed

D'Auria, John M; Keller, Roderich; Ladouceur, Keith; Lapi, Suzanne E; Ruth, Thomas J; Schmor, Paul

2013-03-01

There is a growing need for the production of radioisotopes for both diagnostic and therapeutic medical applications. Radioisotopes that are produced using the (n,γ) or (γ,n) reactions, however, typically result in samples with low specific activity (radioactivity∕gram) due to the high abundance of target material of the same element. One method to effectively remove the isotopic impurity is electro-magnetic mass separation. An Ion Source Test Facility has been constructed at TRIUMF to develop high-intensity, high-efficiency, reliable ion sources for purification of radioactive isotopes, particularly those used in nuclear medicine. In progress studies are presented.

42 CFR 414.506 - Procedures for public consultation for payment for a new clinical diagnostic laboratory test.

Code of Federal Regulations, 2010 CFR

2010-10-01

... a new clinical diagnostic laboratory test. 414.506 Section 414.506 Public Health CENTERS FOR... FOR PART B MEDICAL AND OTHER HEALTH SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.506 Procedures for public consultation for payment for a new clinical diagnostic laboratory test...

42 CFR 414.506 - Procedures for public consultation for payment for a new clinical diagnostic laboratory test.

Code of Federal Regulations, 2011 CFR

2011-10-01

... a new clinical diagnostic laboratory test. 414.506 Section 414.506 Public Health CENTERS FOR... FOR PART B MEDICAL AND OTHER HEALTH SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.506 Procedures for public consultation for payment for a new clinical diagnostic laboratory test...

Understanding the properties of diagnostic tests - Part 2: Likelihood ratios.

PubMed

Ranganathan, Priya; Aggarwal, Rakesh

2018-01-01

Diagnostic tests are used to identify subjects with and without disease. In a previous article in this series, we examined some attributes of diagnostic tests - sensitivity, specificity, and predictive values. In this second article, we look at likelihood ratios, which are useful for the interpretation of diagnostic test results in everyday clinical practice.

X-ray transport and radiation response assessment (XTRRA) experiments at the National Ignition Facility

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

Fournier, K. B., E-mail: fournier2@llnl.gov; Brown, C. G.; Yeoman, M. F.

2016-11-15

Our team has developed an experimental platform to evaluate the x-ray-generated stress and impulse in materials. Experimental activities include x-ray source development, design of the sample mounting hardware and sensors interfaced to the National Ignition Facility’s diagnostics insertion system, and system integration into the facility. This paper focuses on the X-ray Transport and Radiation Response Assessment (XTRRA) test cassettes built for these experiments. The test cassette is designed to position six samples at three predetermined distances from the source, each known to within ±1% accuracy. Built-in calorimeters give in situ measurements of the x-ray environment along the sample lines ofmore » sight. The measured accuracy of sample responses as well as planned modifications to the XTRRA cassette is discussed.« less

X-ray transport and radiation response assessment (XTRRA) experiments at the National Ignition Facility

DOE PAGES

Fournier, K. B.; Brown, Jr., C. G.; Yeoman, M. F.; ...

2016-08-10

Our team has developed an experimental platform to evaluate the x-ray-generated stress and impulse in materials. Experimental activities include x-ray source development, design of the sample mounting hardware and sensors interfaced to the NIF’s diagnostics insertion system, and system integration into the facility. This paper focuses on the X-ray Transport and Radiation Response Assessment (XTRRA) test cassettes built for these experiments. The test cassette is designed to position six samples at three predetermined distances from the source, each known to within ±1% accuracy. Built in calorimeters give in situ measurements of the x-ray environment along the sample lines of sight.more » We discuss the measured accuracy of sample responses, as well as planned modifications to the XTRRA cassette.« less

The diagnostic accuracy of serological tests for Lyme borreliosis in Europe: a systematic review and meta-analysis.

PubMed

Leeflang, M M G; Ang, C W; Berkhout, J; Bijlmer, H A; Van Bortel, W; Brandenburg, A H; Van Burgel, N D; Van Dam, A P; Dessau, R B; Fingerle, V; Hovius, J W R; Jaulhac, B; Meijer, B; Van Pelt, W; Schellekens, J F P; Spijker, R; Stelma, F F; Stanek, G; Verduyn-Lunel, F; Zeller, H; Sprong, H

2016-03-25

Interpretation of serological assays in Lyme borreliosis requires an understanding of the clinical indications and the limitations of the currently available tests. We therefore systematically reviewed the accuracy of serological tests for the diagnosis of Lyme borreliosis in Europe. We searched EMBASE en MEDLINE and contacted experts. Studies evaluating the diagnostic accuracy of serological assays for Lyme borreliosis in Europe were eligible. Study selection and data-extraction were done by two authors independently. We assessed study quality using the QUADAS-2 checklist. We used a hierarchical summary ROC meta-regression method for the meta-analyses. Potential sources of heterogeneity were test-type, commercial or in-house, Ig-type, antigen type and study quality. These were added as covariates to the model, to assess their effect on test accuracy. Seventy-eight studies evaluating an Enzyme-Linked ImmunoSorbent assay (ELISA) or an immunoblot assay against a reference standard of clinical criteria were included. None of the studies had low risk of bias for all QUADAS-2 domains. Sensitivity was highly heterogeneous, with summary estimates: erythema migrans 50% (95% CI 40% to 61%); neuroborreliosis 77% (95% CI 67% to 85%); acrodermatitis chronica atrophicans 97% (95% CI 94% to 99%); unspecified Lyme borreliosis 73% (95% CI 53% to 87%). Specificity was around 95% in studies with healthy controls, but around 80% in cross-sectional studies. Two-tiered algorithms or antibody indices did not outperform single test approaches. The observed heterogeneity and risk of bias complicate the extrapolation of our results to clinical practice. The usefulness of the serological tests for Lyme disease depends on the pre-test probability and subsequent predictive values in the setting where the tests are being used. Future diagnostic accuracy studies should be prospectively planned cross-sectional studies, done in settings where the test will be used in practice.

Market surveillance of in vitro diagnostics by the BfArM until end 2010: how safe are products for tumor diagnostics?

PubMed

Siekmeier, R; Wetzel, D

2013-01-01

The European Directive 98/79/EC on in vitro diagnostic medical devices (IVD) regulates the marketing and post market surveillance of IVD in the European Economic Area. In cases of incidents and field corrective actions the manufacturers have to inform the responsible Competent Authorities (CA). In Germany, the Federal Institute for Drugs and Medical Devices (BfArM) is the responsible CA for most IVD. In this study all notifications regarding IVD (tests, calibrators, kits, and control materials, except laboratory analyzers) for tumor diagnostics received by the BfArM between begin 1999 until end of 2010 were analyzed. All notifications were analyzed in respect to the type of product, the source of notification, the underlying product defects and the corrective actions performed. In the observation period, a total of 2,851 notifications were received of which 84 were related to IVD for tumor diagnostics included in this study (clinical chemistry - 63, histology - 6, molecular biology - 3, rapid tests - 12). Reports were received from manufacturers (68 cases), CA (8 cases), users (4 cases) and other sources (4 cases). In the group of IVD based on clinical chemistry means, the affected products were mostly those for the measurement of prostate specific antigen (PSA, 14 cases), human chorion gonadotropine (13 cases), carcino embryonic antigen (6 cases), CA 19-9 (6 cases), α(1)-fetoprotein (6 cases) and CA 125 (5 cases), whereas in test strips 9 out of the 12 notifications were related to PSA. Investigations of the manufacturers were able to identify the underlying root causes of product failures in 66 cases (78.6%). In 10 cases (11.9%) the root cause remained unclear and in 6 cases and 2 cases (7.1% and 2.4%) a product failure was excluded or a user error was the underlying cause. Most common root causes of product failures were material defects (24 cases) and manufacturing errors (15 cases). Corrective actions were performed by the manufacturers in 64 cases (76.2%) and were predominantly (multiple entries possible) customer information (62 cases, mandatory in case of a recall), recalls (45 cases), modifications in production or quality management (45 cases) and design changes (14 cases). The obtained results suggest that the system for post marketing surveillance of IVD is an established tool to enhance product safety and provides valuable information on product specific problems serving for improvement of product safety.

Comparing diagnostic tests on benefit-risk.

PubMed

Pennello, Gene; Pantoja-Galicia, Norberto; Evans, Scott

2016-01-01

Comparing diagnostic tests on accuracy alone can be inconclusive. For example, a test may have better sensitivity than another test yet worse specificity. Comparing tests on benefit risk may be more conclusive because clinical consequences of diagnostic error are considered. For benefit-risk evaluation, we propose diagnostic yield, the expected distribution of subjects with true positive, false positive, true negative, and false negative test results in a hypothetical population. We construct a table of diagnostic yield that includes the number of false positive subjects experiencing adverse consequences from unnecessary work-up. We then develop a decision theory for evaluating tests. The theory provides additional interpretation to quantities in the diagnostic yield table. It also indicates that the expected utility of a test relative to a perfect test is a weighted accuracy measure, the average of sensitivity and specificity weighted for prevalence and relative importance of false positive and false negative testing errors, also interpretable as the cost-benefit ratio of treating non-diseased and diseased subjects. We propose plots of diagnostic yield, weighted accuracy, and relative net benefit of tests as functions of prevalence or cost-benefit ratio. Concepts are illustrated with hypothetical screening tests for colorectal cancer with test positive subjects being referred to colonoscopy.

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

Koivisto, H., E-mail: hannu.koivisto@phys.jyu.fi; Kalvas, T.; Tarvainen, O.

Several ion source related research and development projects are in progress at the Department of Physics, University of Jyväskylä (JYFL). The work can be divided into investigation of the ion source plasma and development of ion sources, ion beams, and diagnostics. The investigation covers the Electron Cyclotron Resonance Ion Source (ECRIS) plasma instabilities, vacuum ultraviolet (VUV) and visible light emission, photon induced electron emission, and the development of plasma diagnostics. The ion source development covers the work performed for radiofrequency-driven negative ion source, RADIS, beam line upgrade of the JYFL 14 GHz ECRIS, and the development of a new room-temperature-magnetmore » 18 GHz ECRIS, HIISI.« less

Occult Blood Testing for Early Detection of Colorectal Cancer: Diagnostic Outcomes

PubMed Central

Hislop, T. Gregory; Morrison, Brenda J.; Hoogewerf, Peter E.; Burns, Sheilagh D.; Sizto, Ronald

1987-01-01

Three thousand five hundred and fifty-four asymptomatic persons from 32 family practices returned hemoccult II tests for colorectal cancer; 2.2% of these returned tests were positive. The diagnoses for the 47 persons with positive tests which were done while on meat restriction included six cancers (1.7/1000) and five polyps (1.4/1000); 18 were diagnosed with other known sources, and 18 were undiagnosed. All polyps and four of six cancers were diagnosed by combined barium enema with sigmoidoscopy or by colonoscopy. Five of six cancers were diagnosed at early stages. Meat restriction, the method of returning the test for analysis, the number of holes completed in the test, and the delay time from completing the test to analysis did not influence the likelihood of a positive test. PMID:20469468

Study on validity of a rapid diagnostic test kit versus light microscopy for malaria diagnosis in Ahmedabad city, India.

PubMed

Vyas, S; Puwar, B; Patel, V; Bhatt, G; Kulkarni, S; Fancy, M

2014-05-01

Light microscopy of blood smears for diagnosis of malaria in the field has several limitations, notably delays in diagnosis. This study in Ahmedabad in Gujarat State, India, evaluated the diagnostic performance of a rapid diagnostic test for malaria (SD Bioline Malaria Ag P.f/Pan) versus blood smear examination as the gold standard. All fever cases presenting at 13 urban health centres were subjected to rapid diagnostic testing and thick and thin blood smears. A total of 677 cases with fever were examined; 135 (20.0%) tested positive by rapid diagnostic test and 86 (12.7%) by blood smear. The sensitivity of the rapid diagnostic test for malaria was 98.8%, specificity was 91.5%, positive predictive value 63.0% and negative predictive value 99.8%. For detection of Plasmodium falciparum the sensitivity of rapid diagnostic test was 100% and specificity was 97.3%. The results show the acceptability of the rapid test as an alternative to light microscopy in the field setting.

The 2016 Academic Emergency Medicine Consensus Conference, "Shared Decision Making in the Emergency Department: Development of a Policy-relevant Patient-centered Research Agenda" Diagnostic Testing Breakout Session Report.

PubMed

Barrett, Tyler W; Rising, Kristin L; Bellolio, M Fernanda; Hall, M Kennedy; Brody, Aaron; Dodd, Kenneth W; Grieser, Mira; Levy, Phillip D; Raja, Ali S; Self, Wesley H; Weingarten, Gail; Hess, Erik P; Hollander, Judd E

2016-12-01

Diagnostic testing is an integral component of patient evaluation in the emergency department (ED). Emergency clinicians frequently use diagnostic testing to more confidently exclude "worst-case" diagnoses rather than to determine the most likely etiology for a presenting complaint. Increased utilization of diagnostic testing has not been associated with reductions in disease-related mortality but has led to increased overall healthcare costs and other unintended consequences (e.g., incidental findings requiring further workup, unnecessary exposure to ionizing radiation or potentially nephrotoxic contrast). Shared decision making (SDM) presents an opportunity for clinicians to discuss the benefits and harms associated with diagnostic testing with patients to more closely tailor testing to patient risk. This article introduces the challenges and opportunities associated with incorporating SDM into emergency care by summarizing the conclusions of the diagnostic testing group at the 2016 Academic Emergency Medicine Consensus Conference on SDM. Three primary domains emerged: 1) characteristics of a condition or test appropriate for SDM, 2) critical elements of and potential barriers to SDM discussions on diagnostic testing, and 3) financial aspects of SDM applied to diagnostic testing. The most critical research questions to improve engagement of patients in their acute care diagnostic decisions were determined by consensus. © 2016 by the Society for Academic Emergency Medicine.

Influence of a source line position on results of EM observations applied to the diagnostics of underground heating system pipelines in urban area

NASA Astrophysics Data System (ADS)

Vetrov, A.

2009-05-01

The condition of underground constructions, communication and supply systems in the cities has to be periodically monitored and controlled in order to prevent their breakage, which can result in serious accident, especially in urban area. The most risk of damage have the underground construction made of steal such as pipelines widely used for water, gas and heat supply. To ensure the pipeline survivability it is necessary to carry out the operative and inexpensive control of pipelines condition. Induced electromagnetic methods of geophysics can be applied to provide such diagnostics. The highly developed surface in urbane area is one of cause hampering the realization of electromagnetic methods of diagnostics. The main problem is in finding of an appropriate place for the source line and electrodes on a limited surface area and their optimal position relative to the observation path to minimize their influence on observed data. Author made a number of experiments of an underground heating system pipeline diagnostics using different position of the source line and electrodes. The experiments were made on a 200 meters section over 2 meters deep pipeline. The admissible length of the source line and angle between the source line and the observation path were determined. The minimal length of the source line for the experiment conditions and accuracy made 30 meters, the maximum admissible angle departure from the perpendicular position made 30 degrees. The work was undertaken in cooperation with diagnostics company DIsSO, Saint-Petersburg, Russia.

Allergen concentration in natural rubber latex.

PubMed

Yeang, H-Y; Hamilton, R G; Bernstein, D I; Arif, S A M; Chow, K-S; Loke, Y-H; Raulf-Heimsoth, M; Wagner, S; Breiteneder, H; Biagini, R E

2006-08-01

Hevea brasiliensis latex serum is commonly used as the in vivo and in vitro reference antigen for latex allergy diagnosis as it contains the full complement of latex allergens. This study quantifies the concentrations of the significant allergens in latex serum and examines its suitability as an antigen source in latex allergy diagnosis and immunotherapy. The serum phase was extracted from centrifuged latex that was repeatedly freeze-thawed or glycerinated. Quantitation of latex allergens was performed by two-site immunoenzymetric assays. The abundance of RNA transcripts of the latex allergens was estimated from the number of their clones in an Expressed Sequence Tags library. The latex allergens, Hev b 1, 2, 3, 4, 5, 6, 7 and 13, were detected in freeze-thawed and glycerinated latex serum at levels ranging from 75 (Hev b 6) to 0.06 nmol/mg total proteins (Hev b 4). Hev b 6 content in the latex was up to a thousand times higher than the other seven latex allergens, depending on source and/or preparation procedure. Allergen concentration was reflected in the abundance of mRNA transcripts. When used as the antigen, latex serum may bias the outcome of latex allergy diagnostic tests towards sensitization to Hev b 6. Tests that make use of latex serum may fail to detect latex-specific IgE reactivity in subjects who are sensitized only to allergens that are present at low concentrations. Latex allergy diagnostics and immunotherapy that use whole latex serum as the antigen source may not be optimal because of the marked imbalance of its constituent allergens.

Leveling the Playing Field: Bringing Development of Biomarkers and Molecular Diagnostics up to the Standards for Drug Development

PubMed Central

Poste, George; Carbone, David P.; Parkinson, David R.; Verweij, Jaap; Hewitt, Stephen; Jessup, J. Milburn

2012-01-01

Molecular diagnostics are increasingly important in clinical research to stratify or identify molecularly profiled patient cohorts for targeted therapies, to modify the dose of a therapeutic, or to assess early response to therapy or monitor patients. Molecular diagnostics can also be used to identify pharmocogenetic risk of adverse drug reactions. The articles of this CCR Focus section on Molecular Diagnosis describe the development and use of markers for medical decision-making in the cancer patient. They define the sources of preanalytic variability to minimize as well as the regulatory and financial challenges in diagnostic development and integration into clinical practice. They also outline an NCI program to assist diagnostic development. Molecular diagnostic clinical tests require rigor in their development and clinical validation with sufficient sensitivity, specificity and validity that is comparable to that used for development of therapeutics. These diagnostics must be offered at a realistic cost that reflects both their clinical value and the costs associated with their development. When genome sequencing technologies move into the clinic, they must be integrated with and traceable to current technology because they may identify more efficient and accurate approaches to drug development. In addition, regulators may define progressive drug approval for companion diagnostics that requires further evidence regarding efficacy and safety before full approval. A way to accomplish this is to emphasize Phase IV post-marketing hypothesis driven clinical trials with biological characterization that permits accurate definition of the association of low prevalence gene alterations with toxicity or response in large cohorts. PMID:22422403

Leveling the playing field: bringing development of biomarkers and molecular diagnostics up to the standards for drug development.

PubMed

Poste, George; Carbone, David P; Parkinson, David R; Verweij, Jaap; Hewitt, Stephen M; Jessup, J Milburn

2012-03-15

Molecular diagnostics are becoming increasingly important in clinical research to stratify or identify molecularly profiled patient cohorts for targeted therapies, to modify the dose of a therapeutic, and to assess early response to therapy or monitor patients. Molecular diagnostics can also be used to identify the pharmacogenetic risk of adverse drug reactions. The articles in this CCR Focus section on molecular diagnosis describe the development and use of markers to guide medical decisions regarding cancer patients. They define sources of preanalytic variability that need to be minimized, as well as the regulatory and financial challenges involved in developing diagnostics and integrating them into clinical practice. They also outline a National Cancer Institute program to assist diagnostic development. Molecular diagnostic clinical tests require rigor in their development and clinical validation, with sensitivity, specificity, and validity comparable to those required for the development of therapeutics. These diagnostics must be offered at a realistic cost that reflects both their clinical value and the costs associated with their development. When genome-sequencing technologies move into the clinic, they must be integrated with and traceable to current technology because they may identify more efficient and accurate approaches to drug development. In addition, regulators may define progressive drug approval for companion diagnostics that requires further evidence regarding efficacy and safety before full approval can be achieved. One way to accomplish this is to emphasize phase IV postmarketing, hypothesis-driven clinical trials with biological characterization that would permit an accurate definition of the association of low-prevalence gene alterations with toxicity or response in large cohorts.

On a gas electron multiplier based synthetic diagnostic for soft x-ray tomography on WEST with focus on impurity transport studies

NASA Astrophysics Data System (ADS)

Jardin, A.; Mazon, D.; Malard, P.; O'Mullane, M.; Chernyshova, M.; Czarski, T.; Malinowski, K.; Kasprowicz, G.; Wojenski, A.; Pozniak, K.

2017-08-01

The tokamak WEST aims at testing ITER divertor high heat flux component technology in long pulse operation. Unfortunately, heavy impurities like tungsten (W) sputtered from the plasma facing components can pollute the plasma core by radiation cooling in the soft x-ray (SXR) range, which is detrimental for the energy confinement and plasma stability. SXR diagnostics give valuable information to monitor impurities and study their transport. The WEST SXR diagnostic is composed of two new cameras based on the Gas Electron Multiplier (GEM) technology. The WEST GEM cameras will be used for impurity transport studies by performing 2D tomographic reconstructions with spectral resolution in tunable energy bands. In this paper, we characterize the GEM spectral response and investigate W density reconstruction thanks to a synthetic diagnostic recently developed and coupled with a tomography algorithm based on the minimum Fisher information (MFI) inversion method. The synthetic diagnostic includes the SXR source from a given plasma scenario, the photoionization, electron cloud transport and avalanche in the detection volume using Magboltz, and tomographic reconstruction of the radiation from the GEM signal. Preliminary studies of the effect of transport on the W ionization equilibrium and on the reconstruction capabilities are also presented.

Nonproliferative and Proliferative Lesions of the Gastrointestinal Tract, Pancreas and Salivary Glands of the Rat and Mouse.

PubMed

Nolte, Thomas; Brander-Weber, Patricia; Dangler, Charles; Deschl, Ulrich; Elwell, Michael R; Greaves, Peter; Hailey, Richard; Leach, Michael W; Pandiri, Arun R; Rogers, Arlin; Shackelford, Cynthia C; Spencer, Andrew; Tanaka, Takuji; Ward, Jerrold M

2016-01-01

The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) project is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature and diagnostic criteria for nonproliferative and proliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature and diagnostic criteria for classifying lesions in the digestive system including the salivary glands and the exocrine pancreas of laboratory rats and mice. Most lesions are illustrated by color photomicrographs. The standardized nomenclature, the diagnostic criteria, and the photomicrographs are also available electronically on the Internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous and age related lesions as well as lesions induced by exposure to test items. Relevant infectious and parasitic lesions are included as well. A widely accepted and utilized international harmonization of nomenclature and diagnostic criteria for the digestive system will decrease misunderstandings among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists.

Nonproliferative and Proliferative Lesions of the Gastrointestinal Tract, Pancreas and Salivary Glands of the Rat and Mouse

PubMed Central

Nolte, Thomas; Brander-Weber, Patricia; Dangler, Charles; Deschl, Ulrich; Elwell, Michael R.; Greaves, Peter; Hailey, Richard; Leach, Michael W.; Pandiri, Arun R.; Rogers, Arlin; Shackelford, Cynthia C.; Spencer, Andrew; Tanaka, Takuji; Ward, Jerrold M.

2016-01-01

The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) project is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature and diagnostic criteria for nonproliferative and proliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature and diagnostic criteria for classifying lesions in the digestive system including the salivary glands and the exocrine pancreas of laboratory rats and mice. Most lesions are illustrated by color photomicrographs. The standardized nomenclature, the diagnostic criteria, and the photomicrographs are also available electronically on the Internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous and age related lesions as well as lesions induced by exposure to test items. Relevant infectious and parasitic lesions are included as well. A widely accepted and utilized international harmonization of nomenclature and diagnostic criteria for the digestive system will decrease misunderstandings among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists. PMID:26973378

Development of diagnostic test instruments to reveal level student conception in kinematic and dynamics

NASA Astrophysics Data System (ADS)

Handhika, J.; Cari, C.; Suparmi, A.; Sunarno, W.; Purwandari, P.

2018-03-01

The purpose of this research was to develop a diagnostic test instrument to reveal students' conceptions in kinematics and dynamics. The diagnostic test was developed based on the content indicator the concept of (1) displacement and distance, (2) instantaneous and average velocity, (3) zero and constant acceleration, (4) gravitational acceleration (5) Newton's first Law, (6) and Newton's third Law. The diagnostic test development model includes: Diagnostic test requirement analysis, formulating test-making objectives, developing tests, checking the validity of the content and the performance of reliability, and application of tests. The Content Validation Index (CVI) results in the category are highly relevant, with a value of 0.85. Three questions get negative Content Validation Ratio CVR) (-0.6), after revised distractors and clarify visual presentation; the CVR become 1 (highly relevant). This test was applied, obtained 16 valid test items, with Cronbach Alpha value of 0.80. It can conclude that diagnostic test can be used to reveal the level of students conception in kinematics and dynamics.

Design and application of multimegawatt X -band deflectors for femtosecond electron beam diagnostics

DOE PAGES

Dolgashev, Valery A.; Bowden, Gordon; Ding, Yuantao; ...

2014-10-02

Performance of the x-ray free electron laser Linac Coherent Light Source (LCLS) and the Facility for Advanced Accelerator Experimental Tests (FACET) is determined by the properties of their extremely short electron bunches. Multi-GeV electron bunches in both LCLS and FACET are less than 100 fs long. Optimization of beam properties and understanding of free-electron laser operation require electron beam diagnostics with time resolution of about 10 fs. We designed, built and commissioned a set of high frequency X-band deflectors which can measure the beam longitudinal space charge distribution and slice energy spread to better than 10 fs resolution at fullmore » LCLS energy (14 GeV), and with 70 fs resolution at full FACET energy (20 GeV). Use of high frequency and high gradient in these devices allows them to reach unprecedented performance. We report on the physics motivation, design considerations, operational configuration, cold tests, and typical results of the X-band deflector systems currently in use at SLAC.« less

Laser power meters as an X-ray power diagnostic for LCLS-II

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

Heimann, Philip; Moeller, Stefan; Carbajo, Sergio

For the LCLS-II X-ray instruments, laser power meters are being developed as compact X-ray power diagnostics to operate at soft and tender X-ray photon energies. These diagnostics can be installed at various locations along an X-ray free-electron laser (FEL) beamline in order to monitor the transmission of X-ray optics along the beam path. In addition, the power meters will be used to determine the absolute X-ray power at the endstations. Here, thermopile power meters, which measure average power, and have been chosen primarily for their compatibility with the high repetition rates at LCLS-II, are evaluated. Here, a number of characteristicsmore » in the soft X-ray range are presented including linearity, calibrations conducted with a photodiode and a gas monitor detector as well as ultra-high-vacuum compatibility tests using residual gas analysis. The application of these power meters for LCLS-II and other X-ray FEL sources is discussed.« less

Laser power meters as an X-ray power diagnostic for LCLS-II.

PubMed

Heimann, Philip; Moeller, Stefan; Carbajo, Sergio; Song, Sanghoon; Dakovski, Georgi; Nordlund, Dennis; Fritz, David

2018-01-01

For the LCLS-II X-ray instruments, laser power meters are being developed as compact X-ray power diagnostics to operate at soft and tender X-ray photon energies. These diagnostics can be installed at various locations along an X-ray free-electron laser (FEL) beamline in order to monitor the transmission of X-ray optics along the beam path. In addition, the power meters will be used to determine the absolute X-ray power at the endstations. Here, thermopile power meters, which measure average power, and have been chosen primarily for their compatibility with the high repetition rates at LCLS-II, are evaluated. A number of characteristics in the soft X-ray range are presented including linearity, calibrations conducted with a photodiode and a gas monitor detector as well as ultra-high-vacuum compatibility tests using residual gas analysis. The application of these power meters for LCLS-II and other X-ray FEL sources is discussed.

Laser power meters as an X-ray power diagnostic for LCLS-II

DOE PAGES

Heimann, Philip; Moeller, Stefan; Carbajo, Sergio; ...

2018-01-01

For the LCLS-II X-ray instruments, laser power meters are being developed as compact X-ray power diagnostics to operate at soft and tender X-ray photon energies. These diagnostics can be installed at various locations along an X-ray free-electron laser (FEL) beamline in order to monitor the transmission of X-ray optics along the beam path. In addition, the power meters will be used to determine the absolute X-ray power at the endstations. Here, thermopile power meters, which measure average power, and have been chosen primarily for their compatibility with the high repetition rates at LCLS-II, are evaluated. Here, a number of characteristicsmore » in the soft X-ray range are presented including linearity, calibrations conducted with a photodiode and a gas monitor detector as well as ultra-high-vacuum compatibility tests using residual gas analysis. The application of these power meters for LCLS-II and other X-ray FEL sources is discussed.« less

30 CFR 250.523 - How long do I keep records of casing pressure and diagnostic tests?

Code of Federal Regulations, 2011 CFR

2011-07-01

... and diagnostic tests? 250.523 Section 250.523 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... long do I keep records of casing pressure and diagnostic tests? Records of casing pressure and diagnostic tests must be kept at the field office nearest the well for a minimum of 2 years. The last casing...

Use of 3×2 tables with an intention to diagnose approach to assess clinical performance of diagnostic tests: meta-analytical evaluation of coronary CT angiography studies

PubMed Central

Schuetz, Georg M; Schlattmann, Peter

2012-01-01

Objective To determine whether a 3×2 table, using an intention to diagnose approach, is better than the “classic” 2×2 table at handling transparent reporting and non-evaluable results, when assessing the accuracy of a diagnostic test. Design Based on a systematic search for diagnostic accuracy studies of coronary computed tomography (CT) angiography, full texts of relevant studies were evaluated to determine whether they could calculate an alternative 3×2 table. To quantify an overall effect, we pooled diagnostic accuracy values according to a meta-analytical approach. Data sources Medline (via PubMed), Embase (via Ovid), and ISI Web of Science electronic databases. Eligibility criteria Prospective English or German language studies comparing coronary CT with conventional coronary angiography in all patients and providing sufficient data for a patient level analysis. Results 120 studies (10 287 patients) were eligible. Studies varied greatly in their approaches to handling non-evaluable findings. We found 26 studies (including 2298 patients) that allowed us to calculate both 2×2 tables and 3×2 tables. Using a bivariate random effects model, we compared the 2×2 table with the 3×2 table, and found significant differences for pooled sensitivity (98.2 (95% confidence interval 96.7 to 99.1) v 92.7 (88.5 to 95.3)), area under the curve (0.99 (0.98 to 1.00) v 0.93 (0.91 to 0.95)), positive likelihood ratio (9.1 (6.2 to 13.3) v 4.4 (3.3 to 6.0)), and negative likelihood ratio (0.02 (0.01 to 0.04) v 0.09 (0.06 to 0.15); (P<0.05)). Conclusion Parameters for diagnostic performance significantly decrease if non-evaluable results are included by a 3×2 table for analysis (intention to diagnose approach). This approach provides a more realistic picture of the clinical potential of diagnostic tests. PMID:23097549

Borehole survey instrument

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

Sharp, H.E.; Lin, J.W. III; Macha, E.S.

1984-12-04

A borehole survey instrument is provided having a meniscus type floating compass member with indicia thereon for indicating azimuth and inclination. A light source is disposed below the indicia for illuminating the indicia upward through the liquid through which the meniscus type floating compass member floats. A lens system is provided for focusing the image of the illuminated compass member upon a film disposed below the compass member. This arrangement permits the centering post for the compass member to be of minimum diameter consistent with rigidity requirements and permits a high angle compass member to indicate angles of inclination approachingmore » ninety degrees. A multiple light bulb light source is utilized and each light bulb is mounted in a manner which permits a single light bulb to illuminate the entire compass member. A hand-held programming and diagnostic unit is provided which may be momentarily electrically mated with the borehole survey tool to input a programmed timed delay and diagnostically test both the condition of the light bulbs utilized as the illumination source and the state of the batteries within the instrument. This hand-held programmable unit eliminates all the mechanical programming switches and permits the instrument to be completely sealed from the pressure, fluids and contaminants normally found in a well bore.« less

Physics-based investigation of negative ion behavior in a negative-ion-rich plasma using integrated diagnostics

NASA Astrophysics Data System (ADS)

Tsumori, K.; Takeiri, Y.; Ikeda, K.; Nakano, H.; Geng, S.; Kisaki, M.; Nagaoka, K.; Tokuzawa, T.; Wada, M.; Sasaki, K.; Nishiyama, S.; Goto, M.; Osakabe, M.

2017-08-01

Total power of 16 MW has been successfully delivered to the plasma confined in the Large Helical Device (LHD) from three Neutral Beam Injectors (NBIs) equipped with negative hydrogen (H-) ion sources. However, the detailed mechanisms from production through extraction of H- ions are still yet to be clarified and a similar size ion source on an independent acceleration test bench called Research and development Negative Ion Source (RNIS) serves as the facility to study physics related to H- production and transport for further improvement of NBI. The production of negative-ion-rich plasma and the H- ions behavior in the beam extraction region in RNIS is being investigated by employing an integrated diagnostic system. Flow patterns of electrons, positive ions and H- ions in the extraction region are described in a two-dimensional map. The measured flow patterns indicate the existence a stagnation region, where the H- flow changes the direction at a distance about 20 mm from the plasma grid. The pattern also suggested the H- flow originated from plasma grid (PG) surface that turned back toward extraction apertures. The turning region seems formed by a layer of combined magnetic field produced by the magnetic filter field and the Electron-Deflection Magnetic (EDM) field created by magnets installed in the extraction electrode.

Systematic review, meta-analysis and economic modelling of molecular diagnostic tests for antibiotic resistance in tuberculosis.

PubMed

Drobniewski, Francis; Cooke, Mary; Jordan, Jake; Casali, Nicola; Mugwagwa, Tendai; Broda, Agnieszka; Townsend, Catherine; Sivaramakrishnan, Anand; Green, Nathan; Jit, Mark; Lipman, Marc; Lord, Joanne; White, Peter J; Abubakar, Ibrahim

2015-05-01

Drug-resistant tuberculosis (TB), especially multidrug-resistant (MDR, resistance to rifampicin and isoniazid) disease, is associated with a worse patient outcome. Drug resistance diagnosed using microbiological culture takes days to weeks, as TB bacteria grow slowly. Rapid molecular tests for drug resistance detection (1 day) are commercially available and may promote faster initiation of appropriate treatment. To (1) conduct a systematic review of evidence regarding diagnostic accuracy of molecular genetic tests for drug resistance, (2) conduct a health-economic evaluation of screening and diagnostic strategies, including comparison of alternative models of service provision and assessment of the value of targeting rapid testing at high-risk subgroups, and (3) construct a transmission-dynamic mathematical model that translates the estimates of diagnostic accuracy into estimates of clinical impact. A standardised search strategy identified relevant studies from EMBASE, PubMed, MEDLINE, Bioscience Information Service (BIOSIS), System for Information on Grey Literature in Europe Social Policy & Practice (SIGLE) and Web of Science, published between 1 January 2000 and 15 August 2013. Additional 'grey' sources were included. Quality was assessed using quality assessment of diagnostic accuracy studies version 2 (QUADAS-2). For each diagnostic strategy and population subgroup, a care pathway was constructed to specify which medical treatments and health services that individuals would receive from presentation to the point where they either did or did not complete TB treatment successfully. A total cost was estimated from a health service perspective for each care pathway, and the health impact was estimated in terms of the mean discounted quality-adjusted life-years (QALYs) lost as a result of disease and treatment. Costs and QALYs were both discounted at 3.5% per year. An integrated transmission-dynamic and economic model was used to evaluate the cost-effectiveness of introducing rapid molecular testing (in addition to culture and drug sensitivity testing). Probabilistic sensitivity analysis was performed to evaluate the impact on cost-effectiveness of diagnostic and treatment time delays, diagnosis and treatment costs, and associated QALYs. A total of 8922 titles and abstracts were identified, with 557 papers being potentially eligible. Of these, 56 studies contained sufficient test information for analysis. All three commercial tests performed well when detecting drug resistance in clinical samples, although with evidence of heterogeneity between studies. Pooled sensitivity for GenoType® MTBDRplus (Hain Lifescience, Nehren, Germany) (isoniazid and rifampicin resistance), INNO-LiPA Rif.TB® (Fujirebio Europe, Ghent, Belgium) (rifampicin resistance) and Xpert® MTB/RIF (Cepheid Inc., Sunnyvale, CA, USA) (rifampicin resistance) was 83.4%, 94.6%, 95.4% and 96.8%, respectively; equivalent pooled specificity was 99.6%, 98.2%, 99.7% and 98.4%, respectively. Results of the transmission model suggest that all of the rapid assays considered here, if added to the current diagnostic pathway, would be cost-saving and achieve a reduction in expected QALY loss compared with current practice. GenoType MTBDRplus appeared to be the most cost-effective of the rapid tests in the South Asian population, although results were similar for GeneXpert. In all other scenarios GeneXpert appeared to be the most cost-effective strategy. Rapid molecular tests for rifampicin and isoniazid resistance were sensitive and specific. They may also be cost-effective when added to culture drug susceptibility testing in the UK. There is global interest in point-of-care testing and further work is needed to review the performance of emerging tests and the wider health-economic impact of decentralised testing in clinics and primary care, as well as non-health-care settings, such as shelters and prisons. This study is registered as PROSPERO CRD42011001537. The National Institute for Health Research Health Technology Assessment programme.

76 FR 49491 - Medicare Program; Section 3113: The Treatment of Certain Complex Diagnostic Laboratory Tests...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-10

...] Medicare Program; Section 3113: The Treatment of Certain Complex Diagnostic Laboratory Tests Demonstration... code under the Treatment of Certain Complex Diagnostic Laboratory Tests Demonstration. The deadline for... interested parties of an opportunity to participate in the Treatment of Certain Complex Diagnostic Laboratory...

The Use of a Mobile Laboratory Unit in Support of Patient Management and Epidemiological Surveillance during the 2005 Marburg Outbreak in Angola

PubMed Central

Grolla, Allen; Jones, Steven M.; Fernando, Lisa; Strong, James E.; Ströher, Ute; Möller, Peggy; Paweska, Janusz T.; Burt, Felicity; Pablo Palma, Pedro; Sprecher, Armand; Formenty, Pierre; Roth, Cathy; Feldmann, Heinz

2011-01-01

Background Marburg virus (MARV), a zoonotic pathogen causing severe hemorrhagic fever in man, has emerged in Angola resulting in the largest outbreak of Marburg hemorrhagic fever (MHF) with the highest case fatality rate to date. Methodology/Principal Findings A mobile laboratory unit (MLU) was deployed as part of the World Health Organization outbreak response. Utilizing quantitative real-time PCR assays, this laboratory provided specific MARV diagnostics in Uige, the epicentre of the outbreak. The MLU operated over a period of 88 days and tested 620 specimens from 388 individuals. Specimens included mainly oral swabs and EDTA blood. Following establishing on site, the MLU operation allowed a diagnostic response in <4 hours from sample receiving. Most cases were found among females in the child-bearing age and in children less than five years of age. The outbreak had a high number of paediatric cases and breastfeeding may have been a factor in MARV transmission as indicated by the epidemiology and MARV positive breast milk specimens. Oral swabs were a useful alternative specimen source to whole blood/serum allowing testing of patients in circumstances of resistance to invasive procedures but limited diagnostic testing to molecular approaches. There was a high concordance in test results between the MLU and the reference laboratory in Luanda operated by the US Centers for Disease Control and Prevention. Conclusions/Significance The MLU was an important outbreak response asset providing support in patient management and epidemiological surveillance. Field laboratory capacity should be expanded and made an essential part of any future outbreak investigation. PMID:21629730

Routine echocardiography in the management of stroke and transient ischaemic attack: a systematic review and economic evaluation.

PubMed

Holmes, Michael; Rathbone, John; Littlewood, Chris; Rawdin, Andrew; Stevenson, Matt; Stevens, John; Archer, Rachel; Evans, Pippa; Wang, Jenny

2014-03-01

Identification of the underlying cause of stroke and transient ischaemic attack (TIA) is important so that preventative therapy can be used to reduce the risk of recurrence. Transthoracic echocardiography (TTE) and transoesophageal echocardiography (TOE) are diagnostic tools used to identify those cardiac sources of stroke that may respond to treatment. (1) Undertake systematic reviews to determine (a) the prevalence of cardiac sources of stroke and TIA and (b) the diagnostic accuracy of echocardiography; (2) undertake a survey to ascertain which guidelines and management strategies are used by UK stroke centres; and (3) evaluate the cost-effectiveness of the addition of TTE to the routine assessment of patients who have had a first-episode diagnosed stroke or TIA in the UK. Bibliographic databases including MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature, PsycINFO and the NHS Economic Evaluation Database were searched from inception to December 2010 (prevalence) or September 2011 (diagnostic accuracy). Bibliographies of related papers were screened and experts were contacted to identify additional published and unpublished references. The systematic reviews were undertaken according to the general principles recommended in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A decision-analytic model was developed to estimate the costs and quality-adjusted life-years accrued by each potential echocardiography strategy in the management of stroke and TIA for patients aged 45, 55 and 65 years. The model took a lifetime horizon and a NHS perspective. Costs and health benefits were discounted at an annual rate of 3.5%. Evidence to enable modelling was found for left atrial thrombus only. The cost-effectiveness of echocardiography is therefore based on all stroke patients being tested but only those with a left atrial thrombus receiving the benefits and harms of treatment. To describe current NHS stroke management practice we provided a questionnaire to the lead clinician of all stroke units in the UK. The searches identified 17,278 citations for the systematic review of the prevalence of potential cardiac sources of stroke and TIA, of which 65 studies were included. Patent foramen ovale was the most frequently reported pathology, followed by atrial septal aneurysm and mitral valve prolapse, with prevalence ranging from 0.25% to 73%, from 0.4% to 28% and from 0% to 31.6% respectively. For the systematic review of the diagnostic accuracy of echocardiography, 16,504 citations were identified, of which 51 studies were included. The pooled sensitivity to detect left atrial thrombus in three studies using transthoracic echocardiography in second harmonic imaging mode (TTEh) was 0.79 [95% credible interval (CrI) 0.47 to 0.94], with a pooled specificity of 1.00 (95% CrI 0.99 to 1.00) compared with TOE. Differences in the diagnostic accuracy of tests occurred mostly in their sensitivity to detect cardiac sources of stroke. No adverse events data were reported. Our principal economic finding is that TTEh is a cost-effective use of NHS resources compared with TOE when clinicians deem it the most appropriate test. The survey showed that the decision-making process for the management of stroke and TIA is very complex and varies considerably by site. It is clear that to accurately describe current management practice a very sophisticated questionnaire would be required. The prevalence review highlights the difficulties that clinicians face when identifying the cause of cardioembolic stroke (the limitations of the tests, the confounding comorbidities and the inherent mobility of blood clots). The diagnostic accuracy review was limited by the small number of studies reporting data or because studies included too few participants with a cardiac pathology, leaving a large degree of uncertainty about the underlying diagnostic accuracy. The economic model has limitations because of the limited data available for important parameters such as the efficacy of treatment in reducing stroke recurrence. The economic analysis indicates that, in those cases in which TTEh is deemed the most appropriate test, it is a cost-effective use of NHS resources. However, this analysis has highlighted a lack of evidence in several areas and the results of the economic evaluation should therefore be treated with caution. There is a need for further evaluation of current echocardiography technologies, the causal associations between potential risk factors and stroke and whether or not anticoagulation therapies prevent recurrent stroke. Studies attempting to establish the prevalence of cardiac sources of stroke should identify all potential risk factors, rule out those that are not relevant and grade the findings according to risk. Research is also needed to reduce the uncertainty around the estimates of the sensitivity and specificity of TTEh and TOE, singly and in combination, in detecting treatable cardiac abnormalities compared with the 'gold standard' in each pathology. The study is registered as PROSPERO no. CRD42011001353. The National Institute for Health Research Health Technology Assessment programme.

A community outbreak of Legionnaires' disease from an industrial cooling tower: assessment of clinical features and diagnostic procedures.

PubMed

Hugosson, Anna; Hjorth, Martin; Bernander, Sverker; Claesson, Berndt E B; Johansson, Agneta; Larsson, Helena; Nolskog, Peter; Pap, Judit; Svensson, Nils; Ulleryd, Peter

2007-01-01

An outbreak of Legionnaires' disease (LD) occurred in Lidköping, Sweden, in August 2004. A cooling tower was identified as the probable source of infection. During the outbreak period an unexpected 3-6-fold increase in pneumonia patients was noted at the local hospital. During 7 weeks LD was diagnosed in 15 patients by urinary antigen and/or sputum culture. Additionally, 15 LD patients were diagnosed later by serology. Patients with LD were generally younger, more healthy, and more often smokers compared to other pneumonia patients. On admittance they had more severe symptoms with high fever and raised CRP levels, and more often hyponatraemia, gastrointestinal and CNS symptoms. A causative agent besides Legionella was found in 2 patients only. A significant titre rise for Mycoplasma and/or Chlamydophila pneumoniae was found in 13 of 29 tested patients with confirmed LD. We conclude that the clinical diagnosis of LD is difficult and that available diagnostic methods detect only a minority of patients in the acute phase. Therefore in severe pneumonia, empirically targeted therapy should be instituted on clinical grounds irrespective of the results of diagnostic tests. The observation of increased antibody levels for M. and C. pneumoniae suggests an unspecific immune reaction and merits further study.

Update on the status of the ITER ECE diagnostic design

NASA Astrophysics Data System (ADS)

Taylor, G.; Austin, M. E.; Basile, A.; Beno, J. H.; Danani, S.; Feder, R.; Houshmandyar, S.; Hubbard, A. E.; Johnson, D. W.; Khodak, A.; Kumar, R.; Kumar, S.; Ouroua, A.; Padasalagi, S. B.; Pandya, H. K. B.; Phillips, P. E.; Rowan, W. L.; Stillerman, J.; Thomas, S.; Udintsev, V. S.; Vayakis, G.; Walsh, M.; Weeks, D.

2017-07-01

Considerable progress has been made on the design of the ITER electron cyclotron emission (ECE) diagnostic over the past two years. Radial and oblique views are still included in the design in order to measure distortions in the electron momentum distribution, but the oblique view has been redirected to reduce stray millimeter radiation from the electron cyclotron heating system. A major challenge has been designing the 1000 K calibration sources and remotely activated mirrors located in the ECE diagnostic shield module (DSM) in the equatorial port plug #09. These critical systems are being modeled and prototypes are being developed. Providing adequate neutron shielding in the DSM while allowing sufficient space for optical components is also a significant challenge. Four 45-meter long low-loss transmission lines transport the 70-1000 GHz ECE from the DSM to the ECE instrumentation room. Prototype transmission lines are being tested, as are the polarization splitter modules that separate O-mode and X-mode polarized ECE. A highly integrated prototype 200-300 GHz radiometer is being tested on the DIII-D tokamak in the USA. Design activities also include integration of ECE signals into the ITER plasma control system and determining the hardware and software architecture needed to control and calibrate the ECE instruments.

Comparison of a Flow Assay for Brucellosis Antibodies with the Reference cELISA Test in West African Bos indicus

PubMed Central

Bronsvoort, Barend M. deC.; Koterwas, Bronwyn; Land, Fiona; Handel, Ian G.; Tucker, James; Morgan, Kenton L.; Tanya, Vincent N.; Abdoel, Theresia H.; Smits, Henk L.

2009-01-01

Brucellosis is considered by the Food and Agricultural Organisation and the World Health Organisation as one of the most widespread zoonoses in the world. It is a major veterinary public health challenge as animals are almost exclusively the source of infection for people. It is often undiagnosed in both human patients and the animal sources and it is widely acknowledged that the epidemiology of brucellosis in humans and animals is poorly understood, particularly in sub-Saharan Africa. It is therefore important to develop better diagnostic tools in order to improve our understanding of the epidemiology and also for use in the field for disease control and eradication. As with any new diagnostic test, it is essential that it is validated in as many populations as possible in order to characterise its performance and improve the interpretation of its results. This paper describes a comparison between a new lateral flow assasy (LFA) for bovine brucellosis and the widely used cELISA in a no gold standard analysis to estimate test performance in this West African cattle population. A Bayesian formulation of the Hui-Walter latent class model incorporated previous studies' data on sensitivity and specificity of the cELISA. The results indicate that the new LFA is very sensitive (∼87%) and highly specific (∼97%). The analysis also suggests that the current cut-off of the cELSIA may not be optimal for this cattle population but alternative cut-offs did not significantly change the estimates of the LFA. This study demonstrates the potential usefulness of this simple to use test in field based surveillance and control which could be easily adopted for use in developing countries with only basic laboratory facilities. PMID:19381332

Light Microscopy Module Imaging Tested and Demonstrated

NASA Technical Reports Server (NTRS)

Gati, Frank

2004-01-01

The Fluids Integrated Rack (FIR), a facility-class payload, and the Light Microscopy Module (LMM), a subrack payload, are integrated research facilities that will fly in the U.S. Laboratory module, Destiny, aboard the International Space Station. Both facilities are being engineered, designed, and developed at the NASA Glenn Research Center by Northrop Grumman Information Technology. The FIR is a modular, multiuser scientific research facility that is one of two racks that make up the Fluids and Combustion Facility (the other being the Combustion Integrated Rack). The FIR has a large volume dedicated for experimental hardware; easily reconfigurable diagnostics, power, and data systems that allow for unique experiment configurations; and customizable software. The FIR will also provide imagers, light sources, power management and control, command and data handling for facility and experiment hardware, and data processing and storage. The first payload in the FIR will be the LMM. The LMM integrated with the FIR is a remotely controllable, automated, on-orbit microscope subrack facility, with key diagnostic capabilities for meeting science requirements--including video microscopy to observe microscopic phenonema and dynamic interactions, interferometry to make thin-film measurements with nanometer resolution, laser tweezers to manipulate micrometer-sized particles, confocal microscopy to provide enhanced three-dimensional visualization of structures, and spectrophotometry to measure the photonic properties of materials. Vibration disturbances were identified early in the LMM development phase as a high risk for contaminating the science microgravity environment. An integrated FIR-LMM test was conducted in Glenn's Acoustics Test Laboratory to assess mechanical sources of vibration and their impact to microscopic imaging. The primary purpose of the test was to characterize the LMM response at the sample location, the x-y stage within the microscope, to vibration emissions from the FIR and LMM support structures.

Disposable cartridge biosensor platform for portable diagnostics

NASA Astrophysics Data System (ADS)

Yaras, Yusuf S.; Cakmak, Onur; Gunduz, Ali B.; Saglam, Gokhan; Olcer, Selim; Mostafazadeh, Aref; Baris, Ibrahim; Civitci, Fehmi; Yaralioglu, Goksen G.; Urey, Hakan

2017-03-01

We developed two types of cantilever-based biosensors for portable diagnostics applications. One sensor is based on MEMS cantilever chip mounted in a microfluidic channel and the other sensor is based on a movable optical fiber placed across a microfluidic channel. Both types of sensors were aimed at direct mechanical measurement of coagulation time in a disposable cartridge using plasma or whole blood samples. There are several similarities and also some important differences between the MEMS based and the optical fiber based solutions. The aim of this paper is to provide a comparison between the two solutions and the results. For both types of sensors, actuation of the cantilever or the moving fiber is achieved using an electro coil and the readout is optical. Since both the actuation and sensing are remote, no electrical connections are required for the cartridge. Therefore it is possible to build low cost disposable cartridges. The reader unit for the cartridge contains light sources, photodetectors, the electro coil, a heater, analog electronics, and a microprocessor. The reader unit has different optical interfaces for the cartridges that have MEMS cantilevers and moving fibers. MEMS based platform has better sensitivity but optomechanical alignment is a challenge and measurements with whole blood were not possible due to high scattering of light by the red blood cells. Fiber sensor based platform has relaxed optomechanical tolerances, ease of manufacturing, and it allows measurements in whole blood. Both sensors were tested using control plasma samples for activated-Partial-Thromboplastin-Time (aPTT) measurements. Control plasma test results matched with the manufacturer's datasheet. Optical fiber based system was tested for aPTT tests with human whole blood samples and the proposed platform provided repeatable test results making the system method of choice for portable diagnostics.

Epidemiology, diagnostics, and management of tuberculosis in domestic cattle and deer in New Zealand in the face of a wildlife reservoir

PubMed Central

Buddle, BM; de Lisle, GW; Griffin, JFT; Hutchings, SA

2015-01-01

Abstract The control of tuberculosis (TB) in cattle and farmed deer in New Zealand has been greatly influenced by the existence of a wildlife reservoir of Mycobacterium bovis infection, principally the Australian brushtail possum (Trichosurus vulpecula). The reduction in possum numbers in areas with endemic M. bovis infection through vigorous vector control operations has been a major contributor to the marked reduction in the number of infected cattle and farmed deer herds in the past two decades. Management of TB in cattle and farmed deer in New Zealand has involved a combination of vector control, regionalisation of diagnostic testing of cattle and deer herds, abattoir surveillance and movement control from vector risk areas. Accurate diagnosis of infected cattle and deer has been a crucial component in the control programme. As the control programme has evolved, test requirements have changed and new tests have been introduced or test interpretations modified. Subspecific strain typing of M. bovis isolates has proved to be a valuable component in the epidemiological investigation of herd breakdowns to identify whether the source of infection was domestic livestock or wildlife. New initiatives will include the use of improved models for analysing diagnostic test data and characterising disease outbreaks leading to faster elimination of infection from herds. The introduction of the National Animal Identification Tracing programme will allow better risk profiling of individual herds and more reliable tracing of animal movements. TB in cattle and farmed deer in New Zealand can only be controlled by eliminating the disease in both domestic livestock and the wildlife reservoir. PMID:24992203

Ion source research and development at University of Jyväskylä: Studies of different plasma processes and towards the higher beam intensities.

PubMed

Koivisto, H; Kalvas, T; Tarvainen, O; Komppula, J; Laulainen, J; Kronholm, R; Ranttila, K; Tuunanen, J; Thuillier, T; Xie, D; Machicoane, G

2016-02-01

Several ion source related research and development projects are in progress at the Department of Physics, University of Jyväskylä (JYFL). The work can be divided into investigation of the ion source plasma and development of ion sources, ion beams, and diagnostics. The investigation covers the Electron Cyclotron Resonance Ion Source (ECRIS) plasma instabilities, vacuum ultraviolet (VUV) and visible light emission, photon induced electron emission, and the development of plasma diagnostics. The ion source development covers the work performed for radiofrequency-driven negative ion source, RADIS, beam line upgrade of the JYFL 14 GHz ECRIS, and the development of a new room-temperature-magnet 18 GHz ECRIS, HIISI.

Diagnostic experiments at a 3 MeV test stand at Rutherford Appleton Laboratory (United Kingdom).

PubMed

Gabor, C; Faircloth, D C; Lee, D A; Lawrie, S R; Letchford, A P; Pozimski, J K

2010-02-01

A front end is currently under construction consisting of a H(-) Penning ion source (65 keV, 60 mA), low energy beam transport (LEBT), and radio frequency quadrupole (3 MeV output energy) with a medium energy beam transport suitable for high power proton applications. Diagnostics can be divided either in destructive techniques such as beam profile monitor, pepperpot, slit-slit emittance scanner (preferably used during commissioning) or nondestructive, permanently installed devices such as photodetachment-based techniques. Another way to determine beam distributions is a scintillator with charge-coupled device camera. First experiments have been performed to control the beam injection into the LEBT. The influence of beam parameters such as particle energy and space-charge compensation on the two-dimensional distribution and profiles will be presented.

Recent H- diagnostics, plasma simulations, and 2X scaled Penning ion source developments at the Rutherford Appleton Laboratory

NASA Astrophysics Data System (ADS)

Lawrie, S. R.; Faircloth, D. C.; Smith, J. D.; Sarmento, T. M.; Whitehead, M. O.; Wood, T.; Perkins, M.; Macgregor, J.; Abel, R.

2018-05-01

A vessel for extraction and source plasma analyses is being used for Penning H- ion source development at the Rutherford Appleton Laboratory. A new set of optical elements including an einzel lens has been installed, which transports over 80 mA of H- beam successfully. Simultaneously, a 2X scaled Penning source has been developed to reduce cathode power density. The 2X source is now delivering a 65 mA H- ion beam at 10% duty factor, meeting its design criteria. The long-term viability of the einzel lens and 2X source is now being evaluated, so new diagnostic devices have been installed. A pair of electrostatic deflector plates is used to correct beam misalignment and perform fast chopping, with a voltage rise time of 24 ns. A suite of four quartz crystal microbalances has shown that the cesium flux in the vacuum vessel is only increased by a factor of two, despite the absence of a dedicated cold trap. Finally, an infrared camera has demonstrated good agreement with thermal simulations but has indicated unexpected heating due to beam loss on the downstream electrode. These types of diagnostics are suitable for monitoring all operational ion sources. In addition to experimental campaigns and new diagnostic tools, the high-performance VSim and COMSOL software packages are being used for plasma simulations of two novel ion thrusters for space propulsion applications. In parallel, a VSim framework has been established to include arbitrary temperature and cesium fields to allow the modeling of surface physics in H- ion sources.

A broadband LED source in visible to short-wave-infrared wavelengths for spectral tumor diagnostics

NASA Astrophysics Data System (ADS)

Hayashi, Daiyu; van Dongen, Anne Marie; Boerekamp, Jack; Spoor, Sandra; Lucassen, Gerald; Schleipen, Jean

2017-06-01

Various tumor types exhibit the spectral fingerprints in the absorption and reflection spectra in visible and especially in near- to short-wave-infrared wavelength ranges. For the purpose of spectral tumor diagnostics by means of diffuse reflectance spectroscopy, we developed a broadband light emitting diode (LED) source consisting of a blue LED for optical excitation, Lu3Al5O12:Ce3+,Cr3+ luminescent garnet for visible to near infrared emissions, and Bismuth doped GeO2 luminescent glass for near-infrared to short-wave infrared emissions. It emits broad-band light emissions continuously in 470-1600 nm with a spectral gap at 900-1000 nm. In comparison to the currently available broadband light sources like halogen lamps, high-pressure discharge lamps and super continuum lasers, the light sources of this paper has significant advantages for spectral tissue diagnostics in high-spectral stability, improved light coupling to optical fibers, potential in low light source cost and enabling battery-drive.

Economic Outcomes With Anatomical Versus Functional Diagnostic Testing for Coronary Artery Disease.

PubMed

Mark, Daniel B; Federspiel, Jerome J; Cowper, Patricia A; Anstrom, Kevin J; Hoffmann, Udo; Patel, Manesh R; Davidson-Ray, Linda; Daniels, Melanie R; Cooper, Lawton S; Knight, J David; Lee, Kerry L; Douglas, Pamela S

2016-07-19

PROMISE (PROspective Multicenter Imaging Study for Evaluation of Chest Pain) found that initial use of at least 64-slice multidetector computed tomography angiography (CTA) versus functional diagnostic testing strategies did not improve clinical outcomes in stable symptomatic patients with suspected coronary artery disease (CAD) requiring noninvasive testing. To conduct an economic analysis for PROMISE (a major secondary aim of the study). Prospective economic study from the U.S. perspective. Comparisons were made according to the intention-to-treat principle, and CIs were calculated using bootstrap methods. (ClinicalTrials.gov: NCT01174550). 190 U.S. centers. 9649 U.S. patients enrolled in PROMISE between July 2010 and September 2013. Median follow-up was 25 months. Technical costs of the initial (outpatient) testing strategy were estimated from Premier Research Database data. Hospital-based costs were estimated using hospital bills and Medicare cost-charge ratios. Physician fees were taken from the Medicare Physician Fee Schedule. Costs were expressed in 2014 U.S. dollars, discounted at 3% annually, and estimated out to 3 years using inverse probability weighting methods. The mean initial testing costs were $174 for exercise electrocardiography; $404 for CTA; $501 to $514 for pharmacologic and exercise stress echocardiography, respectively; and $946 to $1132 for exercise and pharmacologic stress nuclear testing, respectively. Mean costs at 90 days were $2494 for the CTA strategy versus $2240 for the functional strategy (mean difference, $254 [95% CI, -$634 to $906]). The difference was associated with more revascularizations and catheterizations (4.25 per 100 patients) with CTA use. After 90 days, the mean cost difference between the groups out to 3 years remained small. Cost weights for test strategies were obtained from sources outside PROMISE. Computed tomography angiography and functional diagnostic testing strategies in patients with suspected CAD have similar costs through 3 years of follow-up. National Heart, Lung, and Blood Institute.

Reporting Diagnostic Scores in Educational Testing: Temptations, Pitfalls, and Some Solutions

ERIC Educational Resources Information Center

Sinharay, Sandip; Puhan, Gautam; Haberman, Shelby J.

2010-01-01

Diagnostic scores are of increasing interest in educational testing due to their potential remedial and instructional benefit. Naturally, the number of educational tests that report diagnostic scores is on the rise, as are the number of research publications on such scores. This article provides a critical evaluation of diagnostic score reporting…

Myasthenia Gravis: Tests and Diagnostic Methods

MedlinePlus

... Focus on MG Newsletter MG Quarterly Test & Diagnostic methods In addition to a complete medical and neurological ... How can I help? About MGFA Test & Diagnostic methods Treatment for MG FAQ's Upcoming Events 2018 MG ...

[Diagnostic kits in parasitology: which controls?].

PubMed

Rossi, P

2004-06-01

The development of new diagnostic tools particularly for some parasitic "neglected diseases", is slowed or even hindered by limited resources assigned for basic and applied research in public institution and private sector. Even if the time-line and costs needed for developing a new In Vitro Diagnostic (IVD) test are generally lower compared to vaccines or new drugs, industry is poorly engaged in investing resources due to the perception of limited markets. To accelerate the development of diagnostics for the world's most deadly diseases, the World Health Organization's (WHO) Special Programme for Research and Training in Tropical Diseases (TDR), the United Nations Development Programme, the World Bank and the Gates Foundation, last year launched a new initiative, FIND (Foundation for Innovative New Diagnostics, www.finddiagnostics.org). The aim is to "apply the latest biotechnology innovations to develop and validate affordable diagnostic tests for diseases of the developing world". Ideally, a new diagnostic test should be accurately evaluated prior to use in medical practice. The first step would be a pre-clinical evaluation, an analytic study to determine its laboratory performance. A crucial point in this phase is the calibration of reagents (antigens, antibodies, DNA probes, etc.) against a standard reference preparation. WHO, through the WHO International Laboratories for Biological Standards, "provides International Biological Reference Preparations which serve as reference sources of defined biological activity expressed in an internationally agreed unit" (www.who.int/biologicals/IBRP/index.htm). Standardization allows "comparison of biological measurements worldwide" and ensures the reliability of diagnostic procedures. These preparations are generally intended for use in the characterization of the activity of secondary reference preparations (regional, national or in-house working standards). Unfortunately, international reference standards for parasitic diseases are not available at present, except for Toxoplasma antibodies. The first international standard reagent for Anti-Toxoplasma Serum was established in 1968 and at present, an international standard reference serum, Anti-toxoplasma serum, human TOXM is available at the National Institute for Biological Standards and Control (NIBSC) in UK. Several collaborative, multicenter studies were carried out to assess the performance of different methods and commercial tests for the diagnosis of toxoplasmosis, by providing to participating laboratories a panel of well-defined sera to be tested. A four-phase process following well-accepted methodological standards for the development of diagnostics, analogous to those internationally accepted for drugs and vaccines was recently proposed. The pre-clinical evaluation, the analytic study to assess sensitivity, specificity, predictive values in laboratory (phase I), should be followed by a proof of principle study to distinguish diseased from healthy persons in easily accessible populations (phase II). The evaluation of test performance in populations of intended use (phase III), and finally the delineation of cost-effectiveness and societal impact of new tests in comparison with existing tools (phase IV) should complete the validation procedure. In this context, national regulatory agencies play a major role in pre-market approval and post-market surveillance of IVDs. The European Community in 1998 approved a directive (Directive 98/79/EC) which rules the marketing of IVD medical devices, in order to harmonise the performance levels and standards in European countries. But, among IVDs for parasitic diseases, only those to detect congenital toxoplasmosis are submitted to defined procedures to provide the verification of products before their placing on the market and the surveillance after their marketing by a notified body, which perform appropriate examinations, tests and inspections to production facilities to verify if the device meets the requirements of the directive. In U.S.A., the Food and Drug Administration (FDA), through the Office of In Vitro Diagnostic Device Evaluation and Safety (OIVD), provides a comprehensive and regulatory activity for IVDs through pre-market evaluation and post-market surveillance. In developing countries, the scarcity of resources limits the procedures through which the national control authority can assure safety, quality and efficacy of products marketed, both imported and locally manufactured.

Implementation of Rapid Molecular Infectious Disease Diagnostics: the Role of Diagnostic and Antimicrobial Stewardship.

PubMed

Messacar, Kevin; Parker, Sarah K; Todd, James K; Dominguez, Samuel R

2017-03-01

New rapid molecular diagnostic technologies for infectious diseases enable expedited accurate microbiological diagnoses. However, diagnostic stewardship and antimicrobial stewardship are necessary to ensure that these technologies conserve, rather than consume, additional health care resources and optimally affect patient care. Diagnostic stewardship is needed to implement appropriate tests for the clinical setting and to direct testing toward appropriate patients. Antimicrobial stewardship is needed to ensure prompt appropriate clinical action to translate faster diagnostic test results in the laboratory into improved outcomes at the bedside. This minireview outlines the roles of diagnostic stewardship and antimicrobial stewardship in the implementation of rapid molecular infectious disease diagnostics. Copyright © 2017 American Society for Microbiology.

Polyphasic approach for differentiating Penicillium nordicum from Penicillium verrucosum.

PubMed

Berni, E; Degola, F; Cacchioli, C; Restivo, F M; Spotti, E

2011-04-01

The aim of this research was to use a polyphasic approach to differentiate Penicillium verrucosum from Penicillium nordicum, to compare different techniques, and to select the most suitable for industrial use. In particular, (1) a cultural technique with two substrates selective for these species; (2) a molecular diagnostic test recently set up and a RAPD procedure derived from this assay; (3) an RP-HPLC analysis to quantify ochratoxin A (OTA) production and (4) an automated system based on fungal carbon source utilisation (Biolog Microstation™) were used. Thirty strains isolated from meat products and originally identified as P. verrucosum by morphological methods were re-examined by newer cultural tests and by PCR methods. All were found to belong to P. nordicum. Their biochemical and chemical characterisation supported the results obtained by cultural and molecular techniques and showed the varied ability in P. verrucosum and P. nordicum to metabolise carbon-based sources and to produce OTA at different concentrations, respectively.

A single mini-barcode test to screen for Australian mammalian predators from environmental samples

PubMed Central

MacDonald, Anna J; Sarre, Stephen D

2017-01-01

Abstract Identification of species from trace samples is now possible through the comparison of diagnostic DNA fragments against reference DNA sequence databases. DNA detection of animals from non-invasive samples, such as predator faeces (scats) that contain traces of DNA from their species of origin, has proved to be a valuable tool for the management of elusive wildlife. However, application of this approach can be limited by the availability of appropriate genetic markers. Scat DNA is often degraded, meaning that longer DNA sequences, including standard DNA barcoding markers, are difficult to recover. Instead, targeted short diagnostic markers are required to serve as diagnostic mini-barcodes. The mitochondrial genome is a useful source of such trace DNA markers because it provides good resolution at the species level and occurs in high copy numbers per cell. We developed a mini-barcode based on a short (178 bp) fragment of the conserved 12S ribosomal ribonucleic acid mitochondrial gene sequence, with the goal of discriminating amongst the scats of large mammalian predators of Australia. We tested the sensitivity and specificity of our primers and can accurately detect and discriminate amongst quolls, cats, dogs, foxes, and devils from trace DNA samples. Our approach provides a cost-effective, time-efficient, and non-invasive tool that enables identification of all 8 medium-large mammal predators in Australia, including native and introduced species, using a single test. With modification, this approach is likely to be of broad applicability elsewhere. PMID:28810700

A class of ejecta transport test problems

NASA Astrophysics Data System (ADS)

Oro, David M.; Hammerberg, J. E.; Buttler, William T.; Mariam, Fesseha G.; Morris, Christopher L.; Rousculp, Chris; Stone, Joseph B.

2012-03-01

Hydro code implementations of ejecta dynamics at shocked interfaces presume a source distribution function of particulate masses and velocities, f0(m,u;t). Some properties of this source distribution function have been determined from Taylor- and supported-shockwave experiments. Such experiments measure the mass moment of f0 under vacuum conditions assuming weak particle-particle interactions and, usually, fully inelastic scattering (capture) of ejecta particles from piezoelectric diagnostic probes. Recently, planar ejection of W particles into vacuum, Ar, and Xe gas atmospheres have been carried out to provide benchmark transport data for transport model development and validation. We present those experimental results and compare them with modeled transport of the W-ejecta particles in Ar and Xe.

Design, installation, commissioning and operation of a beamlet monitor in the negative ion beam test stand at NIFS

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

Antoni, V.; Agostinetti, P.; Brombin, M.

2015-04-08

In the framework of the accompanying activity for the development of the two neutral beam injectors for the ITER fusion experiment, an instrumented beam calorimeter is being designed at Consorzio RFX, to be used in the SPIDER test facility (particle energy 100keV; beam current 50A), with the aim of testing beam characteristics and to verify the source proper operation. The main components of the instrumented calorimeter are one-directional carbon-fibre-carbon composite tiles. Some prototype tiles have been used as a small-scale version of the entire calorimeter in the test stand of the neutral beam injectors of the LHD experiment, with themore » aim of characterising the beam features in various operating conditions. The extraction system of the NIFS test stand source was modified, by applying a mask to the first gridded electrode, in order to isolate only a subset of the beamlets, arranged in two 3×5 matrices, resembling the beamlet groups of the ITER beam sources. The present contribution gives a description of the design of the diagnostic system, including the numerical simulations of the expected thermal pattern. Moreover the dedicated thermocouple measurement system is presented. The beamlet monitor was successfully used for a full experimental campaign, during which the main parameters of the source, mainly the arc power and the grid voltages, were varied. This contribution describes the methods of fitting and data analysis applied to the infrared images of the camera to recover the beamlet optics characteristics, in order to quantify the response of the system to different operational conditions. Some results concerning the beamlet features are presented as a function of the source parameters.« less

A reassessment of ground water flow conditions and specific yield at Borden and Cape Cod

USGS Publications Warehouse

Grimestad, Garry

2002-01-01

Recent widely accepted findings respecting the origin and nature of specific yield in unconfined aquifers rely heavily on water level changes observed during two pumping tests, one conducted at Borden, Ontario, Canada, and the other at Cape Cod, Massachusetts. The drawdown patterns observed during those tests have been taken as proof that unconfined specific yield estimates obtained from long-duration pumping tests should approach the laboratory-estimated effective porosity of representative aquifer formation samples. However, both of the original test reports included direct or referential descriptions of potential supplemental sources of pumped water that would have introduced intractable complications and errors into straightforward interpretations of the drawdown observations if actually present. Searches for evidence of previously neglected sources were performed by screening the original drawdown observations from both locations for signs of diagnostic skewing that should be present only if some of the extracted water was derived from sources other than main aquifer storage. The data screening was performed using error-guided computer assisted fitting techniques, capable of accurately sensing and simulating the effects of a wide range of non-traditional and external sources. The drawdown curves from both tests proved to be inconsistent with traditional single-source pumped aquifer models but consistent with site-specific alternatives that included significant contributions of water from external sources. The corrected pumping responses shared several important features. Unsaturated drainage appears to have ceased effectively at both locations within the first day of pumping, and estimates of specific yield stabilized at levels considerably smaller than the corresponding laboratory-measured or probable effective porosity. Separate sequential analyses of progressively later field observations gave stable and nearly constant specific yield estimates for each location, with no evidence from either test that more prolonged pumping would have induced substantially greater levels of unconfined specific yield.

Effect of Point-of-Care Diagnostics on Maternal Outcomes in Human Immunodeficiency Virus–Infected Women: Systematic Review and Meta-analysis

PubMed Central

Mashamba-Thompson, Tivani P; Morgan, Rebecca L; Sartorius, Benn; Dennis, Brittany; Drain, Paul K; Thabane, Lehana

2017-01-01

Introduction The World Health Organization advocates for increased accessibility of HIV-related point-of-care (POC) diagnostics in settings that lack laboratory infrastructure. The aim of this study is to assess the impact of POC diagnostics on maternal health outcomes in HIV-infected women. Methods A systematic literature review used multiple data sources as follows: Cochrane Infectious Disease Group Specialized Register; Cochrane Central Register of Control Trials, published in The Cochrane Library; PubMed; EBSCOhost and LILACS from January 2000 to October 2015. References of included studies were hand searched. Randomized controlled trials (RCTs) and observational studies examining health outcomes of HIV-infected women were eligible for inclusion in this review. The Cochrane Risk of Bias tool was used for bias assessment of the included studies. PRISMA guidelines were used for reporting. Results Of the 695 studies identified, six retrievable studies (five cross-sectional studies and one case control study) met the inclusion criteria and were included in this study. These studies examined a total of 167 HIV-infected women in different study settings. No studies reported evidence of CD4 count, viral load and TB, and the syphilis POC test impact on HIV-infected women was not found by this study. Included studies reported the impact of various HIV rapid tests across the following five maternal outcomes: timely receipt of results with pooled effect size (ES) = 1.00 (95% confidence interval [CI]: (0.98; 1.02); enabling partner testing, ES = 0.95 (0.85; 1.04); prevention of mother-to-child transmission of HIV, ES = 0.86 (0.79; 0.93); linkage to antiretroviral treatment (ART), ES = 0.76 (0.69; 0.84); and linkage to HIV care, ES = 0.50 (0.18; 0.82). No studies reported evidence of the impact of POC testing on maternal mortality or maternal and child morbidity of HIV-infected women. Conclusions The review provides an international overview of the impact of HIV POC diagnostics on maternal outcomes in HIV-infected women, showing the evidence that the HIV POC test is significantly associated with decreased mother-to-child transmission of HIV and increased linkage to ART and HIV care for HIV-infected women. It also revealed a gap in the literature aimed at assessing the impact of POC diagnostics on maternal morbidity and mortality in HIV-infected women. PMID:29242711

The Importance of Conditional Probability in Diagnostic Reasoning and Clinical Decision Making: A Primer for the Eye Care Practitioner.

PubMed

Sanfilippo, Paul G; Hewitt, Alex W; Mackey, David A

2017-04-01

To outline and detail the importance of conditional probability in clinical decision making and discuss the various diagnostic measures eye care practitioners should be aware of in order to improve the scope of their clinical practice. We conducted a review of the importance of conditional probability in diagnostic testing for the eye care practitioner. Eye care practitioners use diagnostic tests on a daily basis to assist in clinical decision making and optimizing patient care and management. These tests provide probabilistic information that can enable the clinician to increase (or decrease) their level of certainty about the presence of a particular condition. While an understanding of the characteristics of diagnostic tests are essential to facilitate proper interpretation of test results and disease risk, many practitioners either confuse or misinterpret these measures. In the interests of their patients, practitioners should be aware of the basic concepts associated with diagnostic testing and the simple mathematical rule that underpins them. Importantly, the practitioner needs to recognize that the prevalence of a disease in the population greatly determines the clinical value of a diagnostic test.

Pearls and pitfalls of allergy diagnostic testing: report from the American College of Allergy, Asthma and Immunology/American Academy of Allergy, Asthma and Immunology Specific IgE Test Task Force.

PubMed

Cox, Linda; Williams, Brock; Sicherer, Scott; Oppenheimer, John; Sher, Larry; Hamilton, Robert; Golden, David

2008-12-01

The intended purpose of this monograph is to provide a general overview of allergy diagnostics for health care professionals who care for patients with allergic disease. For a more comprehensive review of allergy diagnostic testing, readers can refer to the Allergy Diagnostic Practice Parameters. A key message is that a positive allergy test result (skin or blood) indicates only the presence of allergen specific IgE (called sensitization). It does not necessarily mean clinical allergy (ie, allergic symptoms with exposure). It is important for this reason that the allergy evaluation be based on the patient's history and directed by a health care professional with sufficient understanding of allergy diagnostic testing to use the information obtained from his/her evaluation of the patient to determine (1) what allergy diagnostic tests to order, (2) how to interpret the allergy diagnostic test results, and (3) how to use the information obtained from the allergy evaluation to develop an appropriate therapeutic treatment plan.

Tagging Water Sources in Atmospheric Models

NASA Technical Reports Server (NTRS)

Bosilovich, M.

2003-01-01

Tagging of water sources in atmospheric models allows for quantitative diagnostics of how water is transported from its source region to its sink region. In this presentation, we review how this methodology is applied to global atmospheric models. We will present several applications of the methodology. In one example, the regional sources of water for the North American Monsoon system are evaluated by tagging the surface evaporation. In another example, the tagged water is used to quantify the global water cycling rate and residence time. We will also discuss the need for more research and the importance of these diagnostics in water cycle studies.

An update on carbon nanotube-enabled X-ray sources for biomedical imaging.

PubMed

Puett, Connor; Inscoe, Christina; Hartman, Allison; Calliste, Jabari; Franceschi, Dora K; Lu, Jianping; Zhou, Otto; Lee, Yueh Z

2018-01-01

A new imaging technology has emerged that uses carbon nanotubes (CNT) as the electron emitter (cathode) for the X-ray tube. Since the performance of the CNT cathode is controlled by simple voltage manipulation, CNT-enabled X-ray sources are ideal for the repetitive imaging steps needed to capture three-dimensional information. As such, they have allowed the development of a gated micro-computed tomography (CT) scanner for small animal research as well as stationary tomosynthesis, an experimental technology for large field-of-view human imaging. The small animal CT can acquire images at specific points in the respiratory and cardiac cycles. Longitudinal imaging therefore becomes possible and has been applied to many research questions, ranging from tumor response to the noninvasive assessment of cardiac output. Digital tomosynthesis (DT) is a low-dose and low-cost human imaging tool that captures some depth information. Known as three-dimensional mammography, DT is now used clinically for breast imaging. However, the resolution of currently-approved DT is limited by the need to swing the X-ray source through space to collect a series of projection views. An array of fixed and distributed CNT-enabled sources provides the solution and has been used to construct stationary DT devices for breast, lung, and dental imaging. To date, over 100 patients have been imaged on Institutional Review Board-approved study protocols. Early experience is promising, showing an excellent conspicuity of soft-tissue features, while also highlighting technical and post-acquisition processing limitations that are guiding continued research and development. Additionally, CNT-enabled sources are being tested in miniature X-ray tubes that are capable of generating adequate photon energies and tube currents for clinical imaging. Although there are many potential applications for these small field-of-view devices, initial experience has been with an X-ray source that can be inserted into the mouth for dental imaging. Conceived less than 20 years ago, CNT-enabled X-ray sources are now being manufactured on a commercial scale and are powering both research tools and experimental human imaging devices. WIREs Nanomed Nanobiotechnol 2018, 10:e1475. doi: 10.1002/wnan.1475 This article is categorized under: Diagnostic Tools > Diagnostic Nanodevices Diagnostic Tools > In Vivo Nanodiagnostics and Imaging. © 2017 Wiley Periodicals, Inc.

42 CFR 414.509 - Reconsideration of basis for and amount of payment for a new clinical diagnostic laboratory test.

Code of Federal Regulations, 2010 CFR

2010-10-01

... for a new clinical diagnostic laboratory test. 414.509 Section 414.509 Public Health CENTERS FOR... FOR PART B MEDICAL AND OTHER HEALTH SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.509 Reconsideration of basis for and amount of payment for a new clinical diagnostic laboratory...

A Novel Field-Deployable Point-of-Care Diagnostic Test for Cutaneous Leishmaniasis

DTIC Science & Technology

2017-10-01

AWARD NUMBER: W81XWH-14-2-0195 TITLE: A Novel Field-Deployable Point-of-Care Diagnostic Test for Cutaneous Leishmaniasis PRINCIPAL INVESTIGATOR...Field-Deployable Point-of-Care Diagnostic Test for Cutaneous Leishmaniasis 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...Month % completion Aim 1: To use simulated field conditions to optimize and produce the established RPA lateral flow diagnostic test for POC

Special Educator's Complete Guide to 109 Diagnostic Tests: How To Select & Interpret Tests, Use Results in IEPs, and Remediate Specific Difficulties.

ERIC Educational Resources Information Center

Pierangelo, Roger; Giuliani, George

This manual is a guide to the special education diagnostic process and covers the various stages of evaluation, interpretation, diagnosis, prescription, and remediation. Test information includes: explanations of the most commonly used diagnostic tests, coverage of the areas measured by each test, interpretation of test patterns for commonly used…

Diagnostic accuracy of contrast-enhanced ultrasound in assessing the therapeutic response to radio frequency ablation for liver tumors: systematic review and meta-analysis.

PubMed

Xuan, Min; Zhou, Fengsheng; Ding, Yan; Zhu, Qiaoying; Dong, Ji; Zhou, Hao; Cheng, Jun; Jiang, Xiao; Wu, Pengxi

2018-04-01

To review the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) used to detect residual or recurrent liver tumors after radiofrequency ablation (RFA). This technique uses contrast-enhanced computer tomography or/and contrast-enhanced magnetic resonance imaging as the gold standard of investigation. MEDLINE, EMBASE, and COCHRANE were systematically searched for all potentially eligible studies comparing CEUS with the reference standard that follows RFA. Risk of bias and applicability concerns were addressed by adopting the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Pooled point estimates for sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratios (DOR) with 95% CI were computed before plotting the sROC (summary receiver operating characteristic) curve. Meta-regression and subgroup analysis were used to identify the source of the heterogeneity that was detected. Publication bias was evaluated using Deeks' funnel plot asymmetry test. Ten eligible studies on 1162 lesions that occurred between 2001 and 2016 were included in the final analysis. The quality of the included studies assessed by the QUADAS-2 tool was considered reasonable. The pooled sensitivity and specificity of CEUS in detecting residual or recurrent liver tumors had the following values: 0.90 (95% CI 0.85-0.94) and 1.00 (95% CI 0.99-1.00), respectively. Overall DOR was 420.10 (95% CI 142.30-1240.20). The sources of heterogeneity could not be precisely identified by meta-regression or subgroup analysis. No evidence of publication bias was found. This study confirmed that CEUS exhibits high sensitivity and specificity in assessing therapeutic responses to RFA for liver tumors.

Underwater Test Diagnostics Using Explosively Excited Argon And Laser Light Photography Techniques

NASA Astrophysics Data System (ADS)

Wisotski, John

1990-01-01

This paper presents results of photographic methods employed in underwater tests used to study high-velocity fragment deceleration, deformation and fracture during the perforation of water-backed plates. These methods employed overlapping ultra-high and very high speed camera recordings using explosively excited argon and ruby-laser light sources that gave ample light to penetrate across a 2.3-meter (7.54-foot) diameter tank of water with enough intensity to photograph displacement-time histories of steel cubes with impact speeds of 1000 to 1500 m/s (3280 to 4920 ft/s) at camera framing rates of 250,000 and 17,000 fr/s, respectively.

[Are urgent imaging tests indicated in the management of acute pancreatitis?].

PubMed

Fornell Pérez, R; Lozano Rodríguez, A

2016-01-01

Acute pancreatitis is a common emergency within abdominal disease. It is accepted that two of three conditions must be fulfilled for its diagnosis: characteristic clinical presentation, characteristic laboratory findings, and/or characteristic diagnostic imaging findings. The first two conditions are the most often used, probably for reasons of efficiency and frequency. Nevertheless, the need for imaging studies is sometimes a source of conflict. For this reason, we decided to review the current evidence regarding the indication of urgent imaging tests in the management of acute pancreatitis. Copyright © 2015 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

Femtosecond Laser Eyewear Protection: Measurements and Precautions

PubMed Central

Stromberg, Christopher J.; Hadler, Joshua A.; Alberding, Brian G.; Heilweil, Edwin J.

2018-01-01

Ultrafast laser systems are becoming more widespread throughout the research and industrial communities yet eye protection for these high power, bright pulsed sources still require scrupulous characterization and testing before use. Femtosecond lasers, with pulses naturally possessing broad-bandwidth and high average power with variable repetition rate, can exhibit spectral side-bands and subtly changing center wavelengths, which may unknowingly affect eyewear safety protection. Pulse spectral characterization and power diagnostics are presented for a 80 MHz, Ti+3:Sapphire, ≈ 800 nm, ≈40 femtosecond oscillator system. Power and spectral transmission for 22 test samples are measured to determine whether they fall within manufacturer specifications. PMID:29353984

Femtosecond Laser Eyewear Protection: Measurements and Precautions.

PubMed

Stromberg, Christopher J; Hadler, Joshua A; Alberding, Brian G; Heilweil, Edwin J

2017-11-01

Ultrafast laser systems are becoming more widespread throughout the research and industrial communities yet eye protection for these high power, bright pulsed sources still require scrupulous characterization and testing before use. Femtosecond lasers, with pulses naturally possessing broad-bandwidth and high average power with variable repetition rate, can exhibit spectral side-bands and subtly changing center wavelengths, which may unknowingly affect eyewear safety protection. Pulse spectral characterization and power diagnostics are presented for a 80 MHz, Ti +3 :Sapphire, ≈ 800 nm, ≈40 femtosecond oscillator system. Power and spectral transmission for 22 test samples are measured to determine whether they fall within manufacturer specifications.

Scientific and technical complex for modeling, researching and testing of rocket-space vehicles’ electric power installations

NASA Astrophysics Data System (ADS)

Bezruchko, Konstantin; Davidov, Albert

2009-01-01

In the given article scientific and technical complex for modeling, researching and testing of rocket-space vehicles' power installations which was created in Power Source Laboratory of National Aerospace University "KhAI" is described. This scientific and technical complex gives the opportunity to replace the full-sized tests on model tests and to reduce financial and temporary inputs at modeling, researching and testing of rocket-space vehicles' power installations. Using the given complex it is possible to solve the problems of designing and researching of rocket-space vehicles' power installations efficiently, and also to provide experimental researches of physical processes and tests of solar and chemical batteries of rocket-space complexes and space vehicles. Scientific and technical complex also allows providing accelerated tests, diagnostics, life-time control and restoring of chemical accumulators for rocket-space vehicles' power supply systems.

How to: evaluate a diagnostic test.

PubMed

Leeflang, Mariska M G; Allerberger, Franz

2018-06-12

The development of an in vitro diagnostic test from a good idea to a clinically relevant tool takes several steps, with more stringent requirements at every step. This article aims to summarize the necessary questions to be asked about a test and to illustrate study designs answering these questions. We also aim to relate the Regulation (EU) 2017/746 to the needs of evidence-based diagnostic testing, where applicable. We used literature on evidence-based diagnostics, a text book on clinical trials in the development and marketing of medical devices and the English version of Regulation 2017/746 of the European Parliament and of the Council on in vitro diagnostic medical devices. The combination of different test uses and different stages of development determine the required test characteristics and suitability of study designs. In an earlier stage of test development it may be crucial to know whether a test can differentiate diseased persons from healthy controls, while this tells us little about how a test will perform in practice. Later stages focus on the diagnostic accuracy of a test in a clinically relevant situation. However, a test that perfectly distinguishes between patients with and without a certain condition may still have little effect on patient outcomes. Therefore, randomized controlled trials of testing may be needed, as well as post-marketing monitoring. Both researchers and users of tests need to be aware of the limitations of diagnostic test accuracy and realize that accuracy is only indirectly linked to people's health status. Copyright © 2018. Published by Elsevier Ltd.

ACER Physics Unit Tests: Unit Tests, Diagnostic Aids, [and] Teachers Handbook.

ERIC Educational Resources Information Center

Australian Council for Educational Research, Hawthorn.

The Physics Unit Tests are designed to assist in the diagnostic evaluation of students' progress in the study of physics during the last two years of secondary schooling. They consist of a collection of 21 separate tests, each related to a different topic, and 21 diagnostic aids corresponding to the tests. The topics covered are: physical…

[Pre- and post-test probability of obstructive coronary artery disease in two diagnostic strategies: relative contributions of exercise ECG and coronary CT angiography].

PubMed

Faria Alves, Miguel; Ferreira, António Miguel; Cardoso, Gonçalo; Saraiva Lopes, Ricardo; Correia, Maria da Graça; Machado Gil, Victor

2013-03-01

The purpose of this study was to assess the change in theoretical probability of coronary artery disease (CAD) in patients with suspected CAD undergoing coronary CT angiography (CCTA) as first line test vs. patients who underwent CCTA after an exercise ECG. Pre- and post-test probabilities of CAD were assessed in 158 patients with suspected CAD undergoing dual-source CCTA as the first-line test (Group A) and in 134 in whom CCTA was performed after an exercise ECG (Group B). Pre-test probabilities were calculated based on age, gender and type of chest pain. Post-test probabilities were calculated according to Bayes' theorem. There were no significant differences between the groups regarding pre-test probability (median 23.5% [13.3-37.8] in group A vs. 20.5% [13.4-34.5] in group B; p=0,479). In group A, the percentage of patients with intermediate likelihood of disease (10-90%) was 90% before testing and 15% after CCTA (p<0,001), while in group B, it was 95% before testing, 87% after exercise ECG (p=NS), and 17% after CCTA (p<0,001). Unlike exercise testing, CCTA is able to reclassify the risk in the majority of patients with an intermediate probability of obstructive CAD. The use of CCTA as a first-line diagnostic test for CAD may be beneficial in this setting. Copyright © 2012 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Orthologous Allergens and Diagnostic Utility of Major Allergen Alt a 1

PubMed Central

Moreno, Antonio; Alcover, Javier; Rodríguez, David; Palacios, Ricardo; Martínez-Naves, Eduardo

2016-01-01

Purpose Hypersensitivity to fungi is associated with rhinoconjunctivitis and asthma. For some fungi, such as Alternaria alternata (A. alternata), the symptoms of asthma are persistent, increasing disease severity and the risk of fatal outcomes. There are a large number of species of fungi but knowledge of them remains limited. This, together with the difficulties in obtaining adequate standardized extracts, means that there remain significant challenges in the diagnosis and immunotherapy of allergy associated with fungi. The type of indoor fungi related to asthma/allergy varies according to geographic, climatic, and seasonal factors, making their study difficult. The aim of this study was to determine hypersensitivity to indoor fungi in a population from Cuenca, Spain. Methods Thirty-five patients with symptoms compatible with rhinitis or asthma who showed clear worsening of their symptoms in their homes or workplace were included. In vivo and in vitro tests were made with a battery of fungal allergens, including the species isolated in the home or workplace. Results Ulocladium botrytis (U. botrytis) and A. alternata were the most representative species as a source of home sensitization. These species showed very high concordance in skin tests, specific IgE, and histamine release. The allergen Alt a 1, which was recognized in all patients, was detected in A. alternata, U. botrytis, and Stemphylium botryosum (S. botryosum). Conclusions U. botrytis and A. alternata were the most representative species as a source of home sensitization. Alt a 1 was recognized in all patients and may be considered a non-species-specific allergen that could be used as a diagnostic source of sensitization to some species of the Pleosporaceae family. PMID:27334781

Meta-analysis for the comparison of two diagnostic tests to a common gold standard: A generalized linear mixed model approach.

PubMed

Hoyer, Annika; Kuss, Oliver

2018-05-01

Meta-analysis of diagnostic studies is still a rapidly developing area of biostatistical research. Especially, there is an increasing interest in methods to compare different diagnostic tests to a common gold standard. Restricting to the case of two diagnostic tests, in these meta-analyses the parameters of interest are the differences of sensitivities and specificities (with their corresponding confidence intervals) between the two diagnostic tests while accounting for the various associations across single studies and between the two tests. We propose statistical models with a quadrivariate response (where sensitivity of test 1, specificity of test 1, sensitivity of test 2, and specificity of test 2 are the four responses) as a sensible approach to this task. Using a quadrivariate generalized linear mixed model naturally generalizes the common standard bivariate model of meta-analysis for a single diagnostic test. If information on several thresholds of the tests is available, the quadrivariate model can be further generalized to yield a comparison of full receiver operating characteristic (ROC) curves. We illustrate our model by an example where two screening methods for the diagnosis of type 2 diabetes are compared.

Upgrade of the BATMAN test facility for H- source development

NASA Astrophysics Data System (ADS)

Heinemann, B.; Fröschle, M.; Falter, H.-D.; Fantz, U.; Franzen, P.; Kraus, W.; Nocentini, R.; Riedl, R.; Ruf, B.

2015-04-01

The development of a radio frequency (RF) driven source for negative hydrogen ions for the neutral beam heating devices of fusion experiments has been successfully carried out at IPP since 1996 on the test facility BATMAN. The required ITER parameters have been achieved with the prototype source consisting of a cylindrical driver on the back side of a racetrack like expansion chamber. The extraction system, called "Large Area Grid" (LAG) was derived from a positive ion accelerator from ASDEX Upgrade (AUG) using its aperture size (ø 8 mm) and pattern but replacing the first two electrodes and masking down the extraction area to 70 cm2. BATMAN is a well diagnosed and highly flexible test facility which will be kept operational in parallel to the half size ITER source test facility ELISE for further developments to improve the RF efficiency and the beam properties. It is therefore planned to upgrade BATMAN with a new ITER-like grid system (ILG) representing almost one ITER beamlet group, namely 5 × 14 apertures (ø 14 mm). Additionally to the standard three grid extraction system a repeller electrode upstream of the grounded grid can optionally be installed which is positively charged against it by 2 kV. This is designated to affect the onset of the space charge compensation downstream of the grounded grid and to reduce the backstreaming of positive ions from the drift space backwards into the ion source. For magnetic filter field studies a plasma grid current up to 3 kA will be available as well as permanent magnets embedded into a diagnostic flange or in an external magnet frame. Furthermore different source vessels and source configurations are under discussion for BATMAN, e.g. using the AUG type racetrack RF source as driver instead of the circular one or modifying the expansion chamber for a more flexible position of the external magnet frame.

Efficient fault diagnosis of helicopter gearboxes

NASA Technical Reports Server (NTRS)

Chin, H.; Danai, K.; Lewicki, D. G.

1993-01-01

Application of a diagnostic system to a helicopter gearbox is presented. The diagnostic system is a nonparametric pattern classifier that uses a multi-valued influence matrix (MVIM) as its diagnostic model and benefits from a fast learning algorithm that enables it to estimate its diagnostic model from a small number of measurement-fault data. To test this diagnostic system, vibration measurements were collected from a helicopter gearbox test stand during accelerated fatigue tests and at various fault instances. The diagnostic results indicate that the MVIM system can accurately detect and diagnose various gearbox faults so long as they are included in training.

Comparison of the test characteristics of procalcitonin to C-reactive protein and leukocytosis for the detection of serious bacterial infections in children presenting with fever without source: a systematic review and meta-analysis.

PubMed

Yo, Chia-Hung; Hsieh, Pei-Shan; Lee, Si-Huei; Wu, Jiunn-Yih; Chang, Shy-Shin; Tasi, Kuang-Chau; Lee, Chien-Chang

2012-11-01

We determine the usefulness of the procalcitonin for early identification of young children at risk for severe bacterial infection among those presenting with fever without source. The design was a systematic review and meta-analysis of diagnostic studies. Data sources were searches of MEDLINE and EMBASE in April 2011. Included were diagnostic studies that evaluated the diagnostic value of procalcitonin alone or compared with other laboratory markers, such as C-reactive protein or leukocyte count, to detect severe bacterial infection in children with fever without source who were aged between 7 days and 36 months. Eight studies were included (1,883 patients) for procalcitonin analysis, 6 (1,265 patients) for C-reactive protein analysis, and 7 (1,649 patients) for leukocyte analysis. The markers differed in their ability to predict serious bacterial infection: procalcitonin (odds ratio [OR] 10.6; 95% confidence interval [CI] 6.9 to 16.0), C-reactive protein (OR 9.83; 95% CI 7.05 to 13.7), and leukocytosis (OR 4.26; 95% CI 3.22 to 5.63). The random-effect model was used for procalcitonin analysis because heterogeneity across studies existed. Overall sensitivity was 0.83 (95% CI 0.70 to 0.91) for procalcitonin, 0.74 (95% CI 0.65 to 0.82) for C-reactive protein, and 0.58 (95% CI 0.49 to 0.67) for leukocyte count. Overall specificity was 0.69 (95% CI 0.59 to 0.85) for procalcitonin, 0.76 (95% CI 0.70 to 0.81) for C-reactive protein, and 0.73 (95% CI 0.67 to 0.77) for leukocyte count. Procalcitonin performs better than leukocyte count and C-reactive protein for detecting serious bacterial infection among children with fever without source. Considering the poor pooled positive likelihood ratio and acceptable pooled negative likelihood ratio, procalcitonin is better for ruling out serious bacterial infection than for ruling it in. Existing studies do not define how best to combine procalcitonin with other clinical information. Copyright © 2012. Published by Mosby, Inc.

Provocation testing to assist craniomandibular pain diagnosis.

PubMed

DuPont, John S; Brown, Christopher E

2010-04-01

Patients with TMD often present with complex pain symptoms, which can make it difficult to reach a diagnosis. Usually palpation of the masticatory muscles and TM joints, range of motion testing and imaging are used in the diagnostic process. Sometimes it is necessary to evaluate the jaw moving muscles from a functional prospective because they cannot be palpated due to inaccessibility or because they have other structures that are more superficial to them. In these instances, provocation testing can be a helpful adjunct in providing some insight into what is occurring in the area being tested and localizing a suspected source of pain. Anesthesia blocking can be used to confirm any positive findings. This article explores several provocation tests that can be used to evaluate conditions of the masticatory musculature, the TM joints and the stylomandibular ligament.

The impact of new trends in POCTs for companion diagnostics, non-invasive testing and molecular diagnostics.

PubMed

Huckle, David

2015-06-01

Point-of-care diagnostics have been slowly developing over several decades and have taken on a new importance in current healthcare delivery for both diagnostics and development of new drugs. Molecular diagnostics have become a key driver of technology change and opened up new areas in companion diagnostics for use alongside pharmaceuticals and in new clinical approaches such as non-invasive testing. Future areas involving smartphone and other information technology advances, together with new developments in molecular biology, microfluidics and surface chemistry are adding to advances in the market. The focus for point-of-care tests with molecular diagnostic technologies is focused on advancing effective applications.

[Dealing with diagnostic uncertainty in general practice].

PubMed

Wübken, Magdalena; Oswald, Jana; Schneider, Antonius

2013-01-01

In general, the prevalence of diseases is low in primary care. Therefore, the positive predictive value of diagnostic tests is lower than in hospitals where patients are highly selected. In addition, the patients present with milder forms of disease; and many diseases might hide behind the initial symptom(s). These facts lead to diagnostic uncertainty which is somewhat inherent to general practice. This narrative review discusses different sources of and reasons for uncertainty and strategies to deal with it in the context of the current literature. Fear of uncertainty correlates with higher diagnostic activities. The attitude towards uncertainty correlates with the choice of medical speciality by vocational trainees or medical students. An intolerance of uncertainty, which still increases as medicine is making steady progress, might partly explain the growing shortage of general practitioners. The bio-psycho-social context appears to be important to diagnostic decision-making. The effect of intuition and heuristics are investigated by cognitive psychologists. It is still unclear whether these aspects are prone to bias or useful, which might depend on the context of medical decisions. Good communication is of great importance to share uncertainty with the patients in a transparent way and to alleviate shared decision-making. Dealing with uncertainty should be seen as an important core component of general practice and needs to be investigated in more detail to improve the respective medical decisions. Copyright © 2013. Published by Elsevier GmbH.

42 CFR 419.2 - Basis of payment.

Code of Federal Regulations, 2012 CFR

2012-10-01

... prospective payment system establishes a national payment rate, standardized for geographic wage differences...) Capital-related costs; (9) Implantable items used in connection with diagnostic X-ray tests, diagnostic laboratory tests, and other diagnostic tests; (10) Durable medical equipment that is implantable; (11...

Imaging modalities for the non-invasive diagnosis of endometriosis.

PubMed

Nisenblat, Vicki; Bossuyt, Patrick M M; Farquhar, Cindy; Johnson, Neil; Hull, M Louise

2016-02-26

About 10% of women of reproductive age suffer from endometriosis. Endometriosis is a costly chronic disease that causes pelvic pain and subfertility. Laparoscopy, the gold standard diagnostic test for endometriosis, is expensive and carries surgical risks. Currently, no non-invasive tests that can be used to accurately diagnose endometriosis are available in clinical practice. This is the first review of diagnostic test accuracy of imaging tests for endometriosis that uses Cochrane methods to provide an update on the rapidly expanding literature in this field. • To provide estimates of the diagnostic accuracy of imaging modalities for the diagnosis of pelvic endometriosis, ovarian endometriosis and deeply infiltrating endometriosis (DIE) versus surgical diagnosis as a reference standard.• To describe performance of imaging tests for mapping of deep endometriotic lesions in the pelvis at specific anatomical sites.Imaging tests were evaluated as replacement tests for diagnostic surgery and as triage tests that would assist decision making regarding diagnostic surgery for endometriosis. We searched the following databases to 20 April 2015: MEDLINE, CENTRAL, EMBASE, CINAHL, PsycINFO, Web of Science, LILACS, OAIster, TRIP, ClinicalTrials.gov, MEDION, DARE, and PubMed. Searches were not restricted to a particular study design or language nor to specific publication dates. The search strategy incorporated words in the title, abstracts, text words across the record and medical subject headings (MeSH). We considered published peer-reviewed cross-sectional studies and randomised controlled trials of any size that included prospectively recruited women of reproductive age suspected of having one or more of the following target conditions: endometrioma, pelvic endometriosis, DIE or endometriotic lesions at specific intrapelvic anatomical locations. We included studies that compared the diagnostic test accuracy of one or more imaging modalities versus findings of surgical visualisation of endometriotic lesions. Two review authors independently collected and performed a quality assessment of data from each study. For each imaging test, data were classified as positive or negative for surgical detection of endometriosis, and sensitivity and specificity estimates were calculated. If two or more tests were evaluated in the same cohort, each was considered as a separate data set. We used the bivariate model to obtain pooled estimates of sensitivity and specificity when sufficient data sets were available. Predetermined criteria for a clinically useful imaging test to replace diagnostic surgery included sensitivity ≥ 94% and specificity ≥ 79%. Criteria for triage tests were set at sensitivity ≥ 95% and specificity ≥ 50%, ruling out the diagnosis with a negative result (SnNout test - if sensitivity is high, a negative test rules out pathology) or at sensitivity ≥ 50% with specificity ≥ 95%, ruling in the diagnosis with a positive result (SpPin test - if specificity is high, a positive test rules in pathology). We included 49 studies involving 4807 women: 13 studies evaluated pelvic endometriosis, 10 endometriomas and 15 DIE, and 33 studies addressed endometriosis at specific anatomical sites. Most studies were of poor methodological quality. The most studied modalities were transvaginal ultrasound (TVUS) and magnetic resonance imaging (MRI), with outcome measures commonly demonstrating diversity in diagnostic estimates; however, sources of heterogeneity could not be reliably determined. No imaging test met the criteria for a replacement or triage test for detecting pelvic endometriosis, albeit TVUS approached the criteria for a SpPin triage test. For endometrioma, TVUS (eight studies, 765 participants; sensitivity 0.93 (95% confidence interval (CI) 0.87, 0.99), specificity 0.96 (95% CI 0.92, 0.99)) qualified as a SpPin triage test and approached the criteria for a replacement and SnNout triage test, whereas MRI (three studies, 179 participants; sensitivity 0.95 (95% CI 0.90, 1.00), specificity 0.91 (95% CI 0.86, 0.97)) met the criteria for a replacement and SnNout triage test and approached the criteria for a SpPin test. For DIE, TVUS (nine studies, 12 data sets, 934 participants; sensitivity 0.79 (95% CI 0.69, 0.89) and specificity 0.94 (95% CI 0.88, 1.00)) approached the criteria for a SpPin triage test, and MRI (six studies, seven data sets, 266 participants; sensitivity 0.94 (95% CI 0.90, 0.97), specificity 0.77 (95% CI 0.44, 1.00)) approached the criteria for a replacement and SnNout triage test. Other imaging tests assessed in small individual studies could not be statistically evaluated.TVUS met the criteria for a SpPin triage test in mapping DIE to uterosacral ligaments, rectovaginal septum, vaginal wall, pouch of Douglas (POD) and rectosigmoid. MRI met the criteria for a SpPin triage test for POD and vaginal and rectosigmoid endometriosis. Transrectal ultrasonography (TRUS) might qualify as a SpPin triage test for rectosigmoid involvement but could not be adequately assessed for other anatomical sites because heterogeneous data were scant. Multi-detector computerised tomography enema (MDCT-e) displayed the highest diagnostic performance for rectosigmoid and other bowel endometriosis and met the criteria for both SpPin and SnNout triage tests, but studies were too few to provide meaningful results.Diagnostic accuracies were higher for TVUS with bowel preparation (TVUS-BP) and rectal water contrast (RWC-TVS) and for 3.0TMRI than for conventional methods, although the paucity of studies precluded statistical evaluation. None of the evaluated imaging modalities were able to detect overall pelvic endometriosis with enough accuracy that they would be suggested to replace surgery. Specifically for endometrioma, TVUS qualified as a SpPin triage test. MRI displayed sufficient accuracy to suggest utility as a replacement test, but the data were too scant to permit meaningful conclusions. TVUS could be used clinically to identify additional anatomical sites of DIE compared with MRI, thus facilitating preoperative planning. Rectosigmoid endometriosis was the only site that could be accurately mapped by using TVUS, TRUS, MRI or MDCT-e. Studies evaluating recent advances in imaging modalities such as TVUS-BP, RWC-TVS, 3.0TMRI and MDCT-e were observed to have high diagnostic accuracies but were too few to allow prudent evaluation of their diagnostic role. In view of the low quality of most of the included studies, the findings of this review should be interpreted with caution. Future well-designed diagnostic studies undertaken to compare imaging tests for diagnostic test accuracy and costs are recommended.

Laboratory Information Systems in Molecular Diagnostics: Why Molecular Diagnostics Data are Different.

PubMed

Lee, Roy E; Henricks, Walter H; Sirintrapun, Sahussapont J

2016-03-01

Molecular diagnostic testing presents new challenges to information management that are yet to be sufficiently addressed by currently available information systems for the molecular laboratory. These challenges relate to unique aspects of molecular genetic testing: molecular test ordering, informed consent issues, diverse specimen types that encompass the full breadth of specimens handled by traditional anatomic and clinical pathology information systems, data structures and data elements specific to molecular testing, varied testing workflows and protocols, diverse instrument outputs, unique needs and requirements of molecular test reporting, and nuances related to the dissemination of molecular pathology test reports. By satisfactorily addressing these needs in molecular test data management, a laboratory information system designed for the unique needs of molecular diagnostics presents a compelling reason to migrate away from the current paper and spreadsheet information management that many molecular laboratories currently use. This paper reviews the issues and challenges of information management in the molecular diagnostics laboratory.

Comparison of strategies for substantiating freedom from scrapie in a sheep flock.

PubMed

Durand, Benoit; Martinez, Marie-José; Calavas, Didier; Ducrot, Christian

2009-04-30

The public health threat represented by a potential circulation of bovine spongiform encephalopathy agent in sheep population has led European animal health authorities to launch large screening and genetic selection programmes. If demonstrated, such a circulation would have dramatic economic consequences for sheep breeding sector. In this context, it is important to evaluate the feasibility of qualification procedures that would allow sheep breeders demonstrating their flock is free from scrapie. Classical approaches, based on surveys designed to detect disease presence, do not account for scrapie specificities: the genetic variations of susceptibility and the absence of live diagnostic test routinely available. Adapting these approaches leads to a paradoxical situation in which a greater amount of testing is needed to substantiate disease freedom in genetically resistant flocks than in susceptible flocks, whereas probability of disease freedom is a priori higher in the former than in the latter. The goal of this study was to propose, evaluate and compare several qualification strategies for demonstrating a flock is free from scrapie. A probabilistic framework was defined that accounts for scrapie specificities and allows solving the preceding paradox. Six qualification strategies were defined that combine genotyping data, diagnostic tests results and flock pedigree. These were compared in two types of simulated flocks: resistant and susceptible flocks. Two strategies allowed demonstrating disease freedom in several years, for the majority of simulated flocks: a strategy in which all the flock animals are genotyped, and a strategy in which only founders animals are genotyped, the flock pedigree being known. In both cases, diagnostic tests are performed on culled animals. The less costly strategy varied according to the genetic context (resistant or susceptible) and to the relative costs of a genotyping exam and of a diagnostic test. This work demonstrates that combining data sources allows substantiating a flock is free from scrapie within a reasonable time frame. Qualification schemes could thus be a useful tool for voluntary or mandatory scrapie control programmes. However, there is no general strategy that would always minimize the costs and choice of the strategy should be adapted to local genetic conditions.

Diagnostic accuracy of Xpert MTB/RIF assay for musculoskeletal tuberculosis: a meta-analysis.

PubMed

Wen, Hai; Li, Pengzhi; Ma, Hong; Lv, Guohua

2017-01-01

Xpert MTB/RIF assay, a rapid and automated real-time nucleic acid amplification test, has been reported for the diagnosis of musculoskeletal tuberculosis (TB) in current years. This meta-analysis aims to determine the diagnostic accuracy of Xpert for the detection of musculoskeletal TB and rifampicin (RIF) resistance. We searched PubMed, Embase, China National Knowledge Infrastructure, and Wanfang for original articles published up to 1st June 2017 to identify studies in which the Xpert assay was applied to diagnose musculoskeletal TB. Pooled estimates were calculated using a random-effects model or a fixed-effects model according to heterogeneity. Summary receiver operating characteristic curves and the area under the curve (AUC) were used to summarize overall diagnostic performance. Deeks' test was performed to evaluate potential publication bias. Twelve studies were identified with a pooled sensitivity and specificity of respectively 0.81 (95% confidence interval [CI] 0.78-0.83) and 0.83 (95% CI 0.80-0.86) of Xpert for the diagnosis of musculoskeletal TB. Xpert was highly sensitive (0.89, 95% CI 0.79-0.95) and highly specific (0.96, 95% CI 0.92-0.98) in detecting RIF resistance. AUC (over 0.9) suggested a relatively high level of overall diagnostic accuracy of Xpert for detecting musculoskeletal TB and RIF resistance. Prevalence and reference standard were indicated to be sources of heterogeneity between studies. No publication bias was found. This study provides available evidence of the rapid and effective role of Xpert in diagnosing musculoskeletal TB and detecting RIF resistance.

[Implementation of cytology images classification--the Bethesda 2001 System--in a group of screened women from Podlaskie region--effect evaluation].

PubMed

Zbroch, Tomasz; Knapp, Paweł Grzegorz; Knapp, Piotr Andrzej

2007-09-01

Increasing knowledge concerning carcinogenesis within cervical epithelium has forced us to make continues modifications of cytology classification of the cervical smears. Eventually, new descriptions of the submicroscopic cytomorphological abnormalities have enabled the implementation of Bethesda System which was meant to take place of the former Papanicolaou classification although temporarily both are sometimes used simultaneously. The aim of this study was to compare results of these two classification systems in the aspect of diagnostic accuracy verified by further tests of the diagnostic algorithm for the cervical lesion evaluation. The study was conducted in the group of women selected from general population, the criteria being the place of living and cervical cancer age risk group, in the consecutive periods of mass screening in Podlaski region. The performed diagnostic tests have been based on the commonly used algorithm, as well as identical laboratory and methodological conditions. Performed assessment revealed comparable diagnostic accuracy of both analyzing classifications, verified by histological examination, although with marked higher specificity for dysplastic lesions with decreased number of HSIL results and increased diagnosis of LSILs. Higher number of performed colposcopies and biopsies were an additional consequence of TBS classification. Results based on Bethesda System made it possible to find the sources and reasons of abnormalities with much greater precision, which enabled causing agent treatment. Two evaluated cytology classification systems, although not much different, depicted higher potential of TBS and better, more effective communication between cytology laboratory and gynecologist, making reasonable implementation of The Bethesda System in the daily cytology screening work.

9 CFR 93.406 - Diagnostic tests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Diagnostic tests. 93.406 Section 93... CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.406 Diagnostic tests. (a) Tuberculosis and brucellosis tests of cattle. Except as provided in paragraph (d) of this section and in §§ 93.418, 93.427(d), and 93...

9 CFR 93.406 - Diagnostic tests.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Diagnostic tests. 93.406 Section 93... CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.406 Diagnostic tests. (a) Tuberculosis and brucellosis tests of cattle. Except as provided in paragraph (d) of this section and in §§ 93.418, 93.427(d), and 93...

A Three-Tier Diagnostic Test to Assess Pre-Service Teachers' Misconceptions about Global Warming, Greenhouse Effect, Ozone Layer Depletion, and Acid Rain

ERIC Educational Resources Information Center

Arslan, Harika Ozge; Cigdemoglu, Ceyhan; Moseley, Christine

2012-01-01

This study describes the development and validation of a three-tier multiple-choice diagnostic test, the atmosphere-related environmental problems diagnostic test (AREPDiT), to reveal common misconceptions of global warming (GW), greenhouse effect (GE), ozone layer depletion (OLD), and acid rain (AR). The development of a two-tier diagnostic test…

A Compact, Tunable Near-UV Source for Quantitative Microgravity Combustion Diagnostics

NASA Technical Reports Server (NTRS)

Peterson, K. A.; Oh, D. B.

1999-01-01

There is a need for improved optical diagnostic methods for use in microgravity combustion research. Spectroscopic methods with fast time response that can provide absolute concentrations and concentration profiles of important chemical species in flames are needed to facilitate the understanding of combustion kinetics in microgravity. Although a variety of sophisticated laser-based diagnostics (such as planar laser induced fluorescence, degenerate four wave mixing and coherent Raman methods) have been applied to the study of combustion in laboratory flames, the instrumentation associated with these methods is not well suited to microgravity drop tower or space station platforms. Important attributes of diagnostic systems for such applications include compact size, low power consumption, ruggedness, and reliability. We describe a diode laser-based near-UV source designed with the constraints of microgravity research in mind. Coherent light near 420 nm is generated by frequency doubling in a nonlinear crystal. This light source is single mode with a very narrow bandwidth suitable for gas phase diagnostics, can be tuned over several 1/cm and can be wavelength modulated at up to MHz frequencies. We demonstrate the usefulness of this source for combustion diagnostics by measuring CH radical concentration profiles in an atmospheric pressure laboratory flame. The radical concentrations are measured using wavelength modulation spectroscopy (WMS) to obtain the line-of-sight integrated absorption for different paths through the flame. Laser induced fluorescence (LIF) measurements are also demonstrated with this instrument, showing the feasibility of simultaneous WMS absorption and LIF measurements with the same light source. LIF detection perpendicular to the laser beam can be used to map relative species densities along the line-of-sight while the integrated absorption available through WMS provides a mathematical constraint on the extraction of quantitative information from the LIF data. Combining absorption with LIF - especially if the measurements are made simultaneously with the same excitation beam - may allow elimination of geometrical factors and effects of intensity fluctuations (common difficulties with the analysis of LIF data) from the analysis.

Diagnostic methods for insect sting allergy.

PubMed

Hamilton, Robert G

2004-08-01

This review overviews advances from mid-2002 to the present in the validation and performance methods used in the diagnosis of Hymenoptera venom-induced immediate-type hypersensitivity. The general diagnostic algorithm for insect sting allergy is initially discussed with an examination of the AAAAI's 2003 revised practice parameter guidelines. Changes as a result of a greater recognition of skin test negative systemic reactors include repeat analysis of all testing and acceptance of serology as a complementary diagnostic test to the skin test. Original data examining concordance of venom-specific IgE results produced by the second-generation Pharmacia CAP System with the Johns Hopkins University radioallergosorbent test are presented. Diagnostic performance of honeybee venom-specific IgE assays used in clinical laboratories in North America is discussed using data from the Diagnostic Allergy Proficiency Survey conducted by the College of American Pathologists. Validity of venom-specific IgE antibody in postmortem blood specimens is demonstrated. The utility of alternative in-vivo (provocation) and in-vitro (basophil-based) diagnostic testing methods is critiqued. This overview supports the following conclusions. Improved practice parameter guidelines include serology and skin test as complementary in supporting a positive clinical history during the diagnostic process. Data are provided which support the analytical performance of commercially available venom-specific IgE antibody serology-based assays. Intentional sting challenge in-vivo provocation, in-vitro basophil flow cytometry (CD63, CD203c) based assays, and in-vitro basophil histamine and sulfidoleukotriene release assays have their utility in the study of difficult diagnostic cases, but their use will remain as supplementary, secondary diagnostic tests.

Comparison of diagnostic techniques for the detection of Cryptosporidium oocysts in animal samples

PubMed Central

Mirhashemi, Marzieh Ezzaty; Zintl, Annetta; Grant, Tim; Lucy, Frances E.; Mulcahy, Grace; De Waal, Theo

2015-01-01

While a large number of laboratory methods for the detection of Cryptosporidium oocysts in faecal samples are now available, their efficacy for identifying asymptomatic cases of cryptosporidiosis is poorly understood. This study was carried out to determine a reliable screening test for epidemiological studies in livestock. In addition, three molecular tests were compared to identify Cryptosporidium species responsible for the infection in cattle, sheep and horses. A variety of diagnostic tests including microscopic (Kinyoun's staining), immunological (Direct Fluorescence Antibody tests or DFAT), enzyme-linked immunosorbent assay (ELISA), and molecular methods (nested PCR) were compared to assess their ability to detect Cryptosporidium in cattle, horse and sheep faecal samples. The results indicate that the sensitivity and specificity of each test is highly dependent on the input samples; while Kinyoun's and DFAT proved to be reliable screening tools for cattle samples, DFAT and PCR analysis (targeted at the 18S rRNA gene fragment) were more sensitive for screening sheep and horse samples. Finally different PCR primer sets targeted at the same region resulted in the preferential amplification of certain Cryptosporidium species when multiple species were present in the sample. Therefore, for identification of Cryptosporidium spp. in the event of asymptomatic cryptosporidiosis, the combination of different 18S rRNA nested PCR primer sets is recommended for further epidemiological applications and also tracking the sources of infection. PMID:25662435

A Colorimetric Enzyme-Linked Immunosorbent Assay (ELISA) Detection Platform for a Point-of-Care Dengue Detection System on a Lab-on-Compact-Disc.

PubMed

Thiha, Aung; Ibrahim, Fatimah

2015-05-18

The enzyme-linked Immunosorbent Assay (ELISA) is the gold standard clinical diagnostic tool for the detection and quantification of protein biomarkers. However, conventional ELISA tests have drawbacks in their requirement of time, expensive equipment and expertise for operation. Hence, for the purpose of rapid, high throughput screening and point-of-care diagnosis, researchers are miniaturizing sandwich ELISA procedures on Lab-on-a-Chip and Lab-on-Compact Disc (LOCD) platforms. This paper presents a novel integrated device to detect and interpret the ELISA test results on a LOCD platform. The system applies absorption spectrophotometry to measure the absorbance (optical density) of the sample using a monochromatic light source and optical sensor. The device performs automated analysis of the results and presents absorbance values and diagnostic test results via a graphical display or via Bluetooth to a smartphone platform which also acts as controller of the device. The efficacy of the device was evaluated by performing dengue antibody IgG ELISA on 64 hospitalized patients suspected of dengue. The results demonstrate high accuracy of the device, with 95% sensitivity and 100% specificity in detection when compared with gold standard commercial ELISA microplate readers. This sensor platform represents a significant step towards establishing ELISA as a rapid, inexpensive and automatic testing method for the purpose of point-of-care-testing (POCT) in resource-limited settings.

Computer based extraction of phenoptypic features of human congenital anomalies from the digital literature with natural language processing techniques.

PubMed

Karakülah, Gökhan; Dicle, Oğuz; Koşaner, Ozgün; Suner, Aslı; Birant, Çağdaş Can; Berber, Tolga; Canbek, Sezin

2014-01-01

The lack of laboratory tests for the diagnosis of most of the congenital anomalies renders the physical examination of the case crucial for the diagnosis of the anomaly; and the cases in the diagnostic phase are mostly being evaluated in the light of the literature knowledge. In this respect, for accurate diagnosis, ,it is of great importance to provide the decision maker with decision support by presenting the literature knowledge about a particular case. Here, we demonstrated a methodology for automated scanning and determining of the phenotypic features from the case reports related to congenital anomalies in the literature with text and natural language processing methods, and we created a framework of an information source for a potential diagnostic decision support system for congenital anomalies.

42 CFR 493.833 - Condition: Diagnostic immunology.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 5 2012-10-01 2012-10-01 false Condition: Diagnostic immunology. 493.833 Section..., Or Any Combination of These Tests § 493.833 Condition: Diagnostic immunology. The specialty of diagnostic immunology includes for purposes of proficiency testing the subspecialties of syphilis serology...

42 CFR 493.833 - Condition: Diagnostic immunology.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 5 2013-10-01 2013-10-01 false Condition: Diagnostic immunology. 493.833 Section..., Or Any Combination of These Tests § 493.833 Condition: Diagnostic immunology. The specialty of diagnostic immunology includes for purposes of proficiency testing the subspecialties of syphilis serology...

42 CFR 493.833 - Condition: Diagnostic immunology.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 5 2014-10-01 2014-10-01 false Condition: Diagnostic immunology. 493.833 Section..., Or Any Combination of These Tests § 493.833 Condition: Diagnostic immunology. The specialty of diagnostic immunology includes for purposes of proficiency testing the subspecialties of syphilis serology...

WE-AB-206-01: Diagnostic Ultrasound Imaging Quality Assurance

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

Zagzebski, J.

The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. The goal of this ultrasound hands-on workshop is to demonstrate quality control (QC) testing in diagnostic ultrasound and to provide updates in ACR ultrasound accreditation requirements. The first half of this workshop will include two presentations reviewing diagnostic ultrasound QA/QC and ACR ultrasound accreditation requirements. The second half of the workshop will include live demonstrations of basic QC tests. An array of ultrasound testing phantoms and ultrasound scanners will be available for attendees to learn diagnostic ultrasound QC in a hands-on environmentmore » with live demonstrations and on-site instructors. The targeted attendees are medical physicists in diagnostic imaging. Learning Objectives: Gain familiarity with common elements of a QA/QC program for diagnostic ultrasound imaging dentify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools Learn ACR ultrasound accreditation requirements Jennifer Walter is an employee of American College of Radiology on Ultrasound Accreditation.« less

Epitope Mapping of Avian Influenza M2e Protein: Different Species Recognise Various Epitopes

PubMed Central

Hasan, Noor Haliza; Ignjatovic, Jagoda; Tarigan, Simson; Peaston, Anne; Hemmatzadeh, Farhid

2016-01-01

A common approach for developing diagnostic tests for influenza virus detection is the use of mouse or rabbit monoclonal and/or polyclonal antibodies against a target antigen of the virus. However, comparative mapping of the target antigen using antibodies from different animal sources has not been evaluated before. This is important because identification of antigenic determinants of the target antigen in different species plays a central role to ensure the efficiency of a diagnostic test, such as competitive ELISA or immunohistochemistry-based tests. Interest in the matrix 2 ectodomain (M2e) protein of avian influenza virus (AIV) as a candidate for a universal vaccine and also as a marker for detection of virus infection in vaccinated animals (DIVA) is the rationale for the selection of this protein for comparative mapping evaluation. This study aimed to map the epitopes of the M2e protein of avian influenza virus H5N1 using chicken, mouse and rabbit monoclonal or monospecific antibodies. Our findings revealed that rabbit antibodies (rAbs) recognized epitope 6EVETPTRN13 of the M2e, located at the N-terminal of the protein, while mouse (mAb) and chicken antibodies (cAbs) recognized epitope 10PTRNEWECK18, located at the centre region of the protein. The findings highlighted the difference between the M2e antigenic determinants recognized by different species that emphasized the importance of comparative mapping of antibody reactivity from different animals to the same antigen, especially in the case of multi-host infectious agents such as influenza. The findings are of importance for antigenic mapping, as well as diagnostic test and vaccine development. PMID:27362795

Performance of turbo high-pitch dual-source CT for coronary CT angiography: first ex vivo and patient experience.

PubMed

Morsbach, Fabian; Gordic, Sonja; Desbiolles, Lotus; Husarik, Daniela; Frauenfelder, Thomas; Schmidt, Bernhard; Allmendinger, Thomas; Wildermuth, Simon; Alkadhi, Hatem; Leschka, Sebastian

2014-08-01

To evaluate image quality, maximal heart rate allowing for diagnostic imaging, and radiation dose of turbo high-pitch dual-source coronary computed tomographic angiography (CCTA). First, a cardiac motion phantom simulating heart rates (HRs) from 60-90 bpm in 5-bpm steps was examined on a third-generation dual-source 192-slice CT (prospective ECG-triggering, pitch 3.2; rotation time, 250 ms). Subjective image quality regarding the presence of motion artefacts was interpreted by two readers on a four-point scale (1, excellent; 4, non-diagnostic). Objective image quality was assessed by calculating distortion vectors. Thereafter, 20 consecutive patients (median, 50 years) undergoing clinically indicated CCTA were included. In the phantom study, image quality was rated diagnostic up to the HR75 bpm, with object distortion being 1 mm or less. Distortion increased above 1 mm at HR of 80-90 bpm. Patients had a mean HR of 66 bpm (47-78 bpm). Coronary segments were of diagnostic image quality for all patients with HR up to 73 bpm. Average effective radiation dose in patients was 0.6 ± 0.3 mSv. Our combined phantom and patient study indicates that CCTA with turbo high-pitch third-generation dual-source 192-slice CT can be performed at HR up to 75 bpm while maintaining diagnostic image quality, being associated with an average radiation dose of 0.6 mSv. • CCTA is feasible with the turbo high-pitch mode. • Turbo high-pitch CCTA provides diagnostic image quality up to 73 bpm. • The radiation dose of high-pitch CCTA is 0.6 mSv on average.

2012 HIV Diagnostics Conference: the molecular diagnostics perspective.

PubMed

Branson, Bernard M; Pandori, Mark

2013-04-01

2012 HIV Diagnostic Conference Atlanta, GA, USA, 12-14 December 2012. This report highlights the presentations and discussions from the 2012 National HIV Diagnostic Conference held in Atlanta (GA, USA), on 12-14 December 2012. Reflecting changes in the evolving field of HIV diagnostics, the conference provided a forum for evaluating developments in molecular diagnostics and their role in HIV diagnosis. In 2010, the HIV Diagnostics Conference concluded with the proposal of a new diagnostic algorithm which included nucleic acid testing to resolve discordant screening and supplemental antibody test results. The 2012 meeting, picking up where the 2010 meeting left off, focused on scientific presentations that assessed this new algorithm and the role played by RNA testing and new developments in molecular diagnostics, including detection of total and integrated HIV-1 DNA, detection and quantification of HIV-2 RNA, and rapid formats for detection of HIV-1 RNA.

Diagnosis of aphasia in stroke populations: A systematic review of language tests

PubMed Central

2018-01-01

Background and purpose Accurate aphasia diagnosis is important in stroke care. A wide range of language tests are available and include informal assessments, tests developed by healthcare institutions and commercially published tests available for purchase in pre-packaged kits. The psychometrics of these tests are often reported online or within the purchased test manuals, not the peer-reviewed literature, therefore the diagnostic capabilities of these measures have not been systematically evaluated. This review aimed to identify both commercial and non-commercial language tests and tests used in stroke care and to examine the diagnostic capabilities of all identified measures in diagnosing aphasia in stroke populations. Methods Language tests were identified through a systematic search of 161 publisher databases, professional and resource websites and language tests reported to be used in stroke care. Two independent reviewers evaluated test manuals or associated resources for cohort or cross-sectional studies reporting the tests’ diagnostic capabilities (sensitivity, specificity, likelihood ratios or diagnostic odds ratios) in differentiating aphasic and non-aphasic stroke populations. Results Fifty-six tests met the study eligibility criteria. Six “non-specialist” brief screening tests reported sensitivity and specificity information, however none of these measures reported to meet the specific diagnostic needs of speech pathologists. The 50 remaining measures either did not report validity data (n = 7); did not compare patient test performance with a comparison group (n = 17); included non-stroke participants within their samples (n = 23) or did not compare stroke patient performance against a language reference standard (n = 3). Diagnostic sensitivity analysis was completed for six speech pathology measures (WAB, PICA, CADL-2, ASHA-FACS, Adult FAVRES and EFA-4), however all studies compared aphasic performance with that of non-stroke healthy controls and were consequently excluded from the review. Conclusions No speech pathology test was found which reported diagnostic data for identifying aphasia in stroke populations. A diagnostically validated post-stroke aphasia test is needed. PMID:29566043

76 FR 76736 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-08

... Project Survey of Rapid Influenza Diagnostic Test (RIDT) Practices in Laboratories-NEW--the Office of...). Background and Brief Description The Survey of Rapid Influenza Diagnostic Testing Practices in Laboratories is a national systematic study investigating rapid influenza diagnostic testing practices in clinical...

76 FR 61153 - Robert Raymond Reppy, D.O.; Decision and Order

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-03

... diagnostic and laboratory tests consistent with good medical care,'' ``[f]ormulate[] a therapeutic plan... examination and appropriate diagnostic and laboratory testing.'' Id. In May 2000, the Louisiana State Board of..., examination, physical examination and appropriate diagnostic and laboratory testing; Discussing with the...

Comparative Analytical Utility of DNA Derived from Alternative Human Specimens for Molecular Autopsy and Diagnostics

PubMed Central

Klassen, Tara L.; von Rüden, Eva-Lotta; Drabek, Janice; Noebels, Jeffrey L.; Goldman, Alica M.

2013-01-01

Genetic testing and research have increased the demand for high-quality DNA that has traditionally been obtained by venipuncture. However, venous blood collection may prove difficult in special populations and when large-scale specimen collection or exchange is prerequisite for international collaborative investigations. Guthrie/FTA card–based blood spots, buccal scrapes, and finger nail clippings are DNA-containing specimens that are uniquely accessible and thus attractive as alternative tissue sources (ATS). The literature details a variety of protocols for extraction of nucleic acids from a singular ATS type, but their utility has not been systematically analyzed in comparison with conventional sources such as venous blood. Additionally, the efficacy of each protocol is often equated with the overall nucleic acid yield but not with the analytical performance of the DNA during mutation detection. Together with a critical in-depth literature review of published extraction methods, we developed and evaluated an all-inclusive approach for serial, systematic, and direct comparison of DNA utility from multiple biological samples. Our results point to the often underappreciated value of these alternative tissue sources and highlight ways to maximize the ATS-derived DNA for optimal quantity, quality, and utility as a function of extraction method. Our comparative analysis clarifies the value of ATS in genomic analysis projects for population-based screening, diagnostics, molecular autopsy, medico-legal investigations, or multi-organ surveys of suspected mosaicisms. PMID:22796560

Systematic Review and Meta-Analysis of Studies Evaluating Diagnostic Test Accuracy: A Practical Review for Clinical Researchers-Part II. Statistical Methods of Meta-Analysis

PubMed Central

Lee, Juneyoung; Kim, Kyung Won; Choi, Sang Hyun; Huh, Jimi

2015-01-01

Meta-analysis of diagnostic test accuracy studies differs from the usual meta-analysis of therapeutic/interventional studies in that, it is required to simultaneously analyze a pair of two outcome measures such as sensitivity and specificity, instead of a single outcome. Since sensitivity and specificity are generally inversely correlated and could be affected by a threshold effect, more sophisticated statistical methods are required for the meta-analysis of diagnostic test accuracy. Hierarchical models including the bivariate model and the hierarchical summary receiver operating characteristic model are increasingly being accepted as standard methods for meta-analysis of diagnostic test accuracy studies. We provide a conceptual review of statistical methods currently used and recommended for meta-analysis of diagnostic test accuracy studies. This article could serve as a methodological reference for those who perform systematic review and meta-analysis of diagnostic test accuracy studies. PMID:26576107

Source diagnostics of polycyclic aromatic hydrocarbons in urban road runoff, dust, rain and canopy throughfall.

PubMed

Zhang, Wei; Zhang, Shucai; Wan, Chao; Yue, Dapan; Ye, Youbin; Wang, Xuejun

2008-06-01

Diagnostic ratios and multivariate analysis were utilized to apportion polycyclic aromatic hydrocarbon (PAH) sources for road runoff, road dust, rain and canopy throughfall based on samples collected in an urban area of Beijing, China. Three sampling sites representing vehicle lane, bicycle lane and branch road were selected. For road runoff and road dust, vehicular emission and coal combustion were identified as major sources, and the source contributions varied among the sampling sites. For rain, three principal components were apportioned representing coal/oil combustion (54%), vehicular emission (34%) and coking (12%). For canopy throughfall, vehicular emission (56%), coal combustion (30%) and oil combustion (14%) were identified as major sources. Overall, the PAH's source for road runoff mainly reflected that for road dust. Despite site-specific sources, the findings at the study area provided a general picture of PAHs sources for the road runoff system in urban area of Beijing.

Compounding diagnostic delays: a qualitative study of point-of-care testing in South Africa.

PubMed

Engel, Nora; Davids, Malika; Blankvoort, Nadine; Pai, Nitika Pant; Dheda, Keertan; Pai, Madhukar

2015-04-01

Successful point-of-care (POC) testing (completion of test-and-treat cycle in one patient encounter) has immense potential to reduce diagnostic and treatment delays, and improve patient and public health outcomes. We explored what tests are done and how in public/private, rural/urban hospitals and clinics in South Africa and whether they can ensure successful POC testing. This qualitative research study examined POC testing across major diseases in Cape Town, Durban and Eastern Cape. We conducted 101 semi-structured interviews and seven focus group discussions with doctors, nurses, community health workers, patients, laboratory technicians, policymakers, hospital managers and diagnostic manufacturers. In South Africa, diagnostics are characterised by a centralised system. Most tests conducted on the spot can be made to work successfully as POC tests. The majority of public/private clinics and smaller hospitals send samples via couriers to centralised laboratories and retrieve results the same way, via internet, fax or phone. The main challenge to POC testing lies in transporting samples and results, while delays risk patient loss from diagnostic/treatment pathways. Strategies to deal with associated delays create new problems, such as artificially prolonged turnaround times, strains on human resources and quality of testing, compounding additional diagnostic and treatment delays. For POC testing to succeed, particular characteristics of diagnostic ecosystems and adaptations of professional practices to overcome associated challenges must be taken into account. © 2014 John Wiley & Sons Ltd.

Rapid diagnostic tests for malaria

PubMed Central

Daily, Jennifer; Hotte, Nora; Dolkart, Caitlin; Cunningham, Jane; Yadav, Prashant

2015-01-01

Abstract Maintaining quality, competitiveness and innovation in global health technology is a constant challenge for manufacturers, while affordability, access and equity are challenges for governments and international agencies. In this paper we discuss these issues with reference to rapid diagnostic tests for malaria. Strategies to control and eliminate malaria depend on early and accurate diagnosis. Rapid diagnostic tests for malaria require little training and equipment and can be performed by non-specialists in remote settings. Use of these tests has expanded significantly over the last few years, following recommendations to test all suspected malaria cases before treatment and the implementation of an evaluation programme to assess the performance of the malaria rapid diagnostic tests. Despite these gains, challenges exist that, if not addressed, could jeopardize the progress made to date. We discuss recent developments in rapid diagnostic tests for malaria, highlight some of the challenges and provide suggestions to address them. PMID:26668438

The impact of a computerised test of attention and activity (QbTest) on diagnostic decision-making in children and young people with suspected attention deficit hyperactivity disorder: single-blind randomised controlled trial.

PubMed

Hollis, Chris; Hall, Charlotte L; Guo, Boliang; James, Marilyn; Boadu, Janet; Groom, Madeleine J; Brown, Nikki; Kaylor-Hughes, Catherine; Moldavsky, Maria; Valentine, Althea Z; Walker, Gemma M; Daley, David; Sayal, Kapil; Morriss, Richard

2018-04-26

Diagnosis of attention deficit hyperactivity disorder (ADHD) relies on subjective methods which can lead to diagnostic uncertainty and delay. This trial evaluated the impact of providing a computerised test of attention and activity (QbTest) report on the speed and accuracy of diagnostic decision-making in children with suspected ADHD. Randomised, parallel, single-blind controlled trial in mental health and community paediatric clinics in England. Participants were 6-17 years-old and referred for ADHD diagnostic assessment; all underwent assessment-as-usual, plus QbTest. Participants and their clinician were randomised to either receive the QbTest report immediately (QbOpen group) or the report was withheld (QbBlind group). The primary outcome was number of consultations until a diagnostic decision confirming/excluding ADHD within 6-months from baseline. Health economic cost-effectiveness and cost utility analysis was conducted. Assessing QbTest Utility in ADHD: A Randomised Controlled Trial was registered at ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT02209116). One hundred and thirty-two participants were randomised to QbOpen group (123 analysed) and 135 to QbBlind group (127 analysed). Clinicians with access to the QbTest report (QbOpen) were more likely to reach a diagnostic decision about ADHD (hazard ratio 1.44, 95% CI 1.04-2.01). At 6-months, 76% of those with a QbTest report had received a diagnostic decision, compared with 50% without. QbTest reduced appointment length by 15% (time ratio 0.85, 95% CI 0.77-0.93), increased clinicians' confidence in their diagnostic decisions (odds ratio 1.77, 95% CI 1.09-2.89) and doubled the likelihood of excluding ADHD. There was no difference in diagnostic accuracy. Health economic analysis showed a position of strict dominance; however, cost savings were small suggesting that the impact of providing the QbTest report within this trial can best be viewed as 'cost neutral'. QbTest may increase the efficiency of ADHD assessment pathway allowing greater patient throughput with clinicians reaching diagnostic decisions faster without compromising diagnostic accuracy. © 2018 The Authors. Journal of Child Psychology and Psychiatry published by John Wiley & Sons Ltd on behalf of Association for Child and Adolescent Mental Health.

An International Comparison Using a Diagnostic Testing Model: Turkish Students' Profile of Mathematical Skills on TIMSS-R

ERIC Educational Resources Information Center

Dogan, Enis; Tatsuoka, Kikumi

2008-01-01

This study illustrates how a diagnostic testing model can be used to make detailed comparisons between student populations participating in international assessments. The performance of Turkish students on the TIMSS-R mathematics test was reanalyzed with a diagnostic testing model called the Rule Space Model. First, mathematical and cognitive…

Common pitfalls in statistical analysis: Understanding the properties of diagnostic tests - Part 1.

PubMed

Ranganathan, Priya; Aggarwal, Rakesh

2018-01-01

In this article in our series on common pitfalls in statistical analysis, we look at some of the attributes of diagnostic tests (i.e., tests which are used to determine whether an individual does or does not have disease). The next article in this series will focus on further issues related to diagnostic tests.

Molecular Diagnostics in Pathology: Time for a Next-Generation Pathologist?

PubMed

Fassan, Matteo

2018-03-01

- Comprehensive molecular investigations of mainstream carcinogenic processes have led to the use of effective molecular targeted agents in most cases of solid tumors in clinical settings. - To update readers regarding the evolving role of the pathologist in the therapeutic decision-making process and the introduction of next-generation technologies into pathology practice. - Current literature on the topic, primarily sourced from the PubMed (National Center for Biotechnology Information, Bethesda, Maryland) database, were reviewed. - Adequate evaluation of cytologic-based and tissue-based predictive diagnostic biomarkers largely depends on both proper pathologic characterization and customized processing of biospecimens. Moreover, increased requests for molecular testing have paralleled the recent, sharp decrease in tumor material to be analyzed-material that currently comprises cytology specimens or, at minimum, small biopsies in most cases of metastatic/advanced disease. Traditional diagnostic pathology has been completely revolutionized by the introduction of next-generation technologies, which provide multigene, targeted mutational profiling, even in the most complex of clinical cases. Combining traditional and molecular knowledge, pathologists integrate the morphological, clinical, and molecular dimensions of a disease, leading to a proper diagnosis and, therefore, the most-appropriate tailored therapy.

LED-based near infrared sensor for cancer diagnostics

NASA Astrophysics Data System (ADS)

Bogomolov, Andrey; Ageev, Vladimir; Zabarylo, Urszula; Usenov, Iskander; Schulte, Franziska; Kirsanov, Dmitry; Belikova, Valeria; Minet, Olaf; Feliksberger, E.; Meshkovsky, I.; Artyushenko, Viacheslav

2016-03-01

Optical spectroscopic technologies are increasingly used for cancer diagnostics. Feasibility of differentiation between malignant and healthy samples of human kidney using Fluorescence, Raman, MIR and NIR spectroscopy has been recently reported . In the present work, a simplification of NIR spectroscopy method has been studied. Traditional high-resolution NIR spectrometry was replaced by an optical sensor based on a set of light-emitting diodes at selected wavelengths as light sources and a photodiode. Two prototypes of the sensor have been developed and tested using 14 in-vitro samples of seven kidney tumor patients. Statistical evaluation of results using principal component analysis and partial least-squares discriminant analysis has been performed. Despite only partial discrimination between tumor and healthy tissue achieved by the presented new technique, the results evidence benefits of LED-based near-infrared sensing used for oncological diagnostics. Publisher's Note: This paper, originally published on 4 March, 2016, was replaced with a corrected/revised version on 7 April, 2016. If you downloaded the original PDF but are unable to access the revision, please contact SPIE Digital Library Customer Service for assistance.

Gynecologic electrical impedance tomograph

NASA Astrophysics Data System (ADS)

Korjenevsky, A.; Cherepenin, V.; Trokhanova, O.; Tuykin, T.

2010-04-01

Electrical impedance tomography extends to the new and new areas of the medical diagnostics: lungs, breast, prostate, etc. The feedback from the doctors who use our breast EIT diagnostic system has induced us to develop the 3D electrical impedance imaging device for diagnostics of the cervix of the uterus - gynecologic impedance tomograph (GIT). The device uses the same measuring approach as the breast imaging system: 2D flat array of the electrodes arranged on the probe with handle is placed against the body. Each of the 32 electrodes of the array is connected in turn to the current source while the rest electrodes acquire the potentials on the surface. The current flows through the electrode of the array and returns through the remote electrode placed on the patient's limb. The voltages are measured relative to another remote electrode. The 3D backprojection along equipotential surfaces is used to reconstruct conductivity distribution up to approximately 1 cm in depth. Small number of electrodes enables us to implement real time imaging with a few frames per sec. rate. The device is under initial testing and evaluation of the imaging capabilities and suitability of usage.

Self-powered integrated microfluidic point-of-care low-cost enabling (SIMPLE) chip

PubMed Central

Yeh, Erh-Chia; Fu, Chi-Cheng; Hu, Lucy; Thakur, Rohan; Feng, Jeffrey; Lee, Luke P.

2017-01-01

Portable, low-cost, and quantitative nucleic acid detection is desirable for point-of-care diagnostics; however, current polymerase chain reaction testing often requires time-consuming multiple steps and costly equipment. We report an integrated microfluidic diagnostic device capable of on-site quantitative nucleic acid detection directly from the blood without separate sample preparation steps. First, we prepatterned the amplification initiator [magnesium acetate (MgOAc)] on the chip to enable digital nucleic acid amplification. Second, a simplified sample preparation step is demonstrated, where the plasma is separated autonomously into 224 microwells (100 nl per well) without any hemolysis. Furthermore, self-powered microfluidic pumping without any external pumps, controllers, or power sources is accomplished by an integrated vacuum battery on the chip. This simple chip allows rapid quantitative digital nucleic acid detection directly from human blood samples (10 to 105 copies of methicillin-resistant Staphylococcus aureus DNA per microliter, ~30 min, via isothermal recombinase polymerase amplification). These autonomous, portable, lab-on-chip technologies provide promising foundations for future low-cost molecular diagnostic assays. PMID:28345028

Diagnostic Accuracy of Copeptin in the Differential Diagnosis of the Polyuria-polydipsia Syndrome: A Prospective Multicenter Study.

PubMed

Timper, Katharina; Fenske, Wiebke; Kühn, Felix; Frech, Nica; Arici, Birsen; Rutishauser, Jonas; Kopp, Peter; Allolio, Bruno; Stettler, Christoph; Müller, Beat; Katan, Mira; Christ-Crain, Mirjam

2015-06-01

The polyuria-polydipsia syndrome comprises primary polydipsia (PP) and central and nephrogenic diabetes insipidus (DI). Correctly discriminating these entities is mandatory, given that inadequate treatment causes serious complications. The diagnostic "gold standard" is the water deprivation test with assessment of arginine vasopressin (AVP) activity. However, test interpretation and AVP measurement are challenging. The objective was to evaluate the accuracy of copeptin, a stable peptide stoichiometrically cosecreted with AVP, in the differential diagnosis of polyuria-polydipsia syndrome. This was a prospective multicenter observational cohort study from four Swiss or German tertiary referral centers of adults >18 years old with the history of polyuria and polydipsia. A standardized combined water deprivation/3% saline infusion test was performed and terminated when serum sodium exceeded 147 mmol/L. Circulating copeptin and AVP levels were measured regularly throughout the test. Final diagnosis was based on the water deprivation/saline infusion test results, clinical information, and the treatment response. Fifty-five patients were enrolled (11 with complete central DI, 16 with partial central DI, 18 with PP, and 10 with nephrogenic DI). Without prior thirsting, a single baseline copeptin level >21.4 pmol/L differentiated nephrogenic DI from other etiologies with a 100% sensitivity and specificity, rendering a water deprivation testing unnecessary in such cases. A stimulated copeptin >4.9 pmol/L (at sodium levels >147 mmol/L) differentiated between patients with PP and patients with partial central DI with a 94.0% specificity and a 94.4% sensitivity. A stimulated AVP >1.8 pg/mL differentiated between the same categories with a 93.0% specificity and a 83.0% sensitivity. This study was limited by incorporation bias from including AVP levels as a diagnostic criterion. Copeptin is a promising new tool in the differential diagnosis of the polyuria-polydipsia syndrome, and a valid surrogate marker for AVP. Primary Funding Sources: Swiss National Science Foundation, University of Basel.

Epidemiology of Schistosomiasis and Usefulness of Indirect Diagnostic Tests in School-Age Children in Cubal, Central Angola

PubMed Central

Bocanegra, Cristina; Gallego, Sara; Mendioroz, Jacobo; Moreno, Milagros; Sulleiro, Elena; Salvador, Fernando; Sikaleta, Nicolau; Nindia, Arlette; Tchipita, Daniel; Joromba, Morais; Kavaya, Sebastiao; Sánchez Montalvá, Adrián; López, Teresa; Molina, Israel

2015-01-01

Introduction Schistosomiasis remains a public health major problem and little is known in many areas, mainly in Sub-Saharan Africa Objectives To assess the burden and risk factors of schistosomiasis and intestinal parasitic helminthes in the children of Cubal, Angola, and to compare different diagnostic approaches for urinary schistosomiasis under field conditions. Methods A cross-sectional study was conducted. Urine and faeces samples of school children were microscopically studied. A random sample of children was obtained from an alphabetically arranged list of children, taking one of two children. Urine dipstick, colorimetric test and macrohaematuria were considered as indirect diagnostic methods and compared to direct urine examination. Possible risk factors for the infection were sex, age, distance to the river and previous treatment with praziquantel; the assessment was performed using Chi-square test. Results A total of 785 (61.18%) children showed S. haematobium eggs in urine; children living within 500 meters from the river had a higher odds for infection: Odds ratio 1.97 (1.45–2.7 CI 95%); urine dipstick showed sensitivity of 96% and specificity of 61.3%, with a positive predictive value; colorimetric test showed sensitivity of 52.5%, specificity of 74.6% and a positive predictive value of 77%. Proteinuria was present in 653 (51.1%) children, being more frequent in children with S. haematobium in urine (75.2%); 32 of 191 stool samples (16%) showed the presence of other intestinal parasites and 8 (4%) for S. haematobium. Conclusions Prevalence of urinary schistosomiasis in our study area is much higher than the national average, considering it as a high-risk community. Proximity to a source of water was a risk factor for the infection. Indirect tests, as urine dipstick and colorimetric test, were useful tools for diagnosis, due to ease of use and low cost. Proteinuria was a common finding, probably showing an early structural damage due to schistosomiasis in this group of children. PMID:26474169

Diagnosing breast cancer using Raman spectroscopy: prospective analysis

NASA Astrophysics Data System (ADS)

Haka, Abigail S.; Volynskaya, Zoya; Gardecki, Joseph A.; Nazemi, Jon; Shenk, Robert; Wang, Nancy; Dasari, Ramachandra R.; Fitzmaurice, Maryann; Feld, Michael S.

2009-09-01

We present the first prospective test of Raman spectroscopy in diagnosing normal, benign, and malignant human breast tissues. Prospective testing of spectral diagnostic algorithms allows clinicians to accurately assess the diagnostic information contained in, and any bias of, the spectroscopic measurement. In previous work, we developed an accurate, internally validated algorithm for breast cancer diagnosis based on analysis of Raman spectra acquired from fresh-frozen in vitro tissue samples. We currently evaluate the performance of this algorithm prospectively on a large ex vivo clinical data set that closely mimics the in vivo environment. Spectroscopic data were collected from freshly excised surgical specimens, and 129 tissue sites from 21 patients were examined. Prospective application of the algorithm to the clinical data set resulted in a sensitivity of 83%, a specificity of 93%, a positive predictive value of 36%, and a negative predictive value of 99% for distinguishing cancerous from normal and benign tissues. The performance of the algorithm in different patient populations is discussed. Sources of bias in the in vitro calibration and ex vivo prospective data sets, including disease prevalence and disease spectrum, are examined and analytical methods for comparison provided.

A novel modification of the Turing test for artificial intelligence and robotics in healthcare.

PubMed

Ashrafian, Hutan; Darzi, Ara; Athanasiou, Thanos

2015-03-01

The increasing demands of delivering higher quality global healthcare has resulted in a corresponding expansion in the development of computer-based and robotic healthcare tools that rely on artificially intelligent technologies. The Turing test was designed to assess artificial intelligence (AI) in computer technology. It remains an important qualitative tool for testing the next generation of medical diagnostics and medical robotics. Development of quantifiable diagnostic accuracy meta-analytical evaluative techniques for the Turing test paradigm. Modification of the Turing test to offer quantifiable diagnostic precision and statistical effect-size robustness in the assessment of AI for computer-based and robotic healthcare technologies. Modification of the Turing test to offer robust diagnostic scores for AI can contribute to enhancing and refining the next generation of digital diagnostic technologies and healthcare robotics. Copyright © 2014 John Wiley & Sons, Ltd.

Decision analysis to complete diagnostic research by closing the gap between test characteristics and cost-effectiveness.

PubMed

Schaafsma, Joanna D; van der Graaf, Yolanda; Rinkel, Gabriel J E; Buskens, Erik

2009-12-01

The lack of a standard methodology in diagnostic research impedes adequate evaluation before implementation of constantly developing diagnostic techniques. We discuss the methodology of diagnostic research and underscore the relevance of decision analysis in the process of evaluation of diagnostic tests. Overview and conceptual discussion. Diagnostic research requires a stepwise approach comprising assessment of test characteristics followed by evaluation of added value, clinical outcome, and cost-effectiveness. These multiple goals are generally incompatible with a randomized design. Decision-analytic models provide an important alternative through integration of the best available evidence. Thus, critical assessment of clinical value and efficient use of resources can be achieved. Decision-analytic models should be considered part of the standard methodology in diagnostic research. They can serve as a valid alternative to diagnostic randomized clinical trials (RCTs).

Development and validation of an immunoperoxidase antigen detection test for improved diagnosis of rabies in Indonesia.

PubMed

Rahmadane, Ibnu; Certoma, Andrea F; Peck, Grantley R; Fitria, Yul; Payne, Jean; Colling, Axel; Shiell, Brian J; Beddome, Gary; Wilson, Susanne; Yu, Meng; Morrissy, Chris; Michalski, Wojtek P; Bingham, John; Gardner, Ian A; Allen, John D

2017-11-01

Rabies continues to pose a significant threat to human and animal health in regions of Indonesia. Indonesia has an extensive network of veterinary diagnostic laboratories and the 8 National laboratories are equipped to undertake diagnostic testing for rabies using the commercially-procured direct fluorescent antibody test (FAT), which is considered the reference (gold standard) test. However, many of the Indonesian Provincial diagnostic laboratories do not have a fluorescence microscope required to undertake the FAT. Instead, certain Provincial laboratories continue to screen samples using a chemical stain-based test (Seller's stain test, SST). This test has low diagnostic sensitivity, with negative SST-tested samples being forwarded to the nearest National laboratory resulting in significant delays for completion of testing and considerable additional costs. This study sought to develop a cost-effective and diagnostically-accurate immunoperoxidase antigen detection (RIAD) test for rabies that can be readily and quickly performed by the resource-constrained Provincial laboratories. This would reduce the burden on the National laboratories and allow more rapid diagnoses and implementation of post-exposure prophylaxis. The RIAD test was evaluated using brain smears fixed with acetone or formalin and its performance was validated by comparison with established rabies diagnostic tests used in Indonesia, including the SST and FAT. A proficiency testing panel was distributed between Provincial laboratories to assess the reproducibility of the test. The performance of the RIAD test was improved by using acetone fixation of brain smears rather than formalin fixation such that it was of equivalent accuracy to that of the World Organisation for Animal Health (OIE)-recommended FAT, with both tests returning median diagnostic sensitivity and specificity values of 0.989 and 0.993, respectively. The RIAD test and FAT had higher diagnostic sensitivity than the SST (median = 0.562). Proficiency testing using a panel of 6 coded samples distributed to 16 laboratories showed that the RIAD test had good reproducibility with an overall agreement of 97%. This study describes the successful development, characterisation and use of a novel RIAD test and its fitness for purpose as a screening test for use in provincial Indonesian veterinary laboratories.

42 CFR 493.921 - Diagnostic immunology.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 5 2010-10-01 2010-10-01 false Diagnostic immunology. 493.921 Section 493.921... Testing Proficiency Testing Programs by Specialty and Subspecialty § 493.921 Diagnostic immunology. The subspecialties under the specialty of immunology for which a program may offer proficiency testing are syphilis...

42 CFR 493.921 - Diagnostic immunology.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 5 2011-10-01 2011-10-01 false Diagnostic immunology. 493.921 Section 493.921... Testing Proficiency Testing Programs by Specialty and Subspecialty § 493.921 Diagnostic immunology. The subspecialties under the specialty of immunology for which a program may offer proficiency testing are syphilis...

42 CFR 493.921 - Diagnostic immunology.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 5 2012-10-01 2012-10-01 false Diagnostic immunology. 493.921 Section 493.921... Testing Proficiency Testing Programs by Specialty and Subspecialty § 493.921 Diagnostic immunology. The subspecialties under the specialty of immunology for which a program may offer proficiency testing are syphilis...

42 CFR 493.921 - Diagnostic immunology.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 5 2014-10-01 2014-10-01 false Diagnostic immunology. 493.921 Section 493.921... Testing Proficiency Testing Programs by Specialty and Subspecialty § 493.921 Diagnostic immunology. The subspecialties under the specialty of immunology for which a program may offer proficiency testing are syphilis...

42 CFR 493.921 - Diagnostic immunology.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 5 2013-10-01 2013-10-01 false Diagnostic immunology. 493.921 Section 493.921... Testing Proficiency Testing Programs by Specialty and Subspecialty § 493.921 Diagnostic immunology. The subspecialties under the specialty of immunology for which a program may offer proficiency testing are syphilis...

Plasma Diagnostics: Use and Justification in an Industrial Environment

NASA Astrophysics Data System (ADS)

Loewenhardt, Peter

1998-10-01

The usefulness and importance of plasma diagnostics have played a major role in the development of plasma processing tools in the semiconductor industry. As can be seen through marketing materials from semiconductor equipment manufacturers, results from plasma diagnostic equipment can be a powerful tool in selling the technological leadership of tool design. Some diagnostics have long been used for simple process control such as optical emission for endpoint determination, but in recent years more sophisticated and involved diagnostic tools have been utilized in chamber and plasma source development and optimization. It is now common to find an assortment of tools at semiconductor equipment companies such as Langmuir probes, mass spectrometers, spatial optical emission probes, impedance, ion energy and ion flux probes. An outline of how the importance of plasma diagnostics has grown at an equipment manufacturer over the last decade will be given, with examples of significant and useful results obtained. Examples will include the development and optimization of an inductive plasma source, trends and hardware effects on ion energy distributions, mass spectrometry influences on process development and investigations of plasma-wall interactions. Plasma diagnostic focus, in-house development and proliferation in an environment where financial justification requirements are both strong and necessary will be discussed.

NGC 3516: Disk Diagnostics from a Windy BLSy1 in a High-State

NASA Astrophysics Data System (ADS)

Turner, Tracey Jane

2005-10-01

Recent advances have shown X-ray flux to be simply correlated with reflection-signatures from the disk and an associated wind. It appears two things are essential to observe the disk/wind: 1) catch the Seyfert in a high-state where disk/wind features show up strongly and 2) separate out reprocessing from distant gas to allow isolation of disk/wind features. NGC 3516 provides the ideal source for further study in this regard. The source is currently in a very high state, which we predict will lead to observable features from the disk and its wind. We request 210 ks XMM exposure on NGC 3156 with supporting Chandra time to test our prediction of flux-linked disk reflection and wind.

Simulation of Fusion Plasmas

ScienceCinema

Holland, Chris [UC San Diego, San Diego, California, United States

2017-12-09

The upcoming ITER experiment (www.iter.org) represents the next major milestone in realizing the promise of using nuclear fusion as a commercial energy source, by moving into the “burning plasma” regime where the dominant heat source is the internal fusion reactions. As part of its support for the ITER mission, the US fusion community is actively developing validated predictive models of the behavior of magnetically confined plasmas. In this talk, I will describe how the plasma community is using the latest high performance computing facilities to develop and refine our models of the nonlinear, multiscale plasma dynamics, and how recent advances in experimental diagnostics are allowing us to directly test and validate these models at an unprecedented level.

Diagnostic Tests to Support Late-Stage Control Programs for Schistosomiasis and Soil-Transmitted Helminthiases.

PubMed

Hawkins, Kenneth R; Cantera, Jason L; Storey, Helen L; Leader, Brandon T; de Los Santos, Tala

2016-12-01

Global efforts to address schistosomiasis and soil-transmitted helminthiases (STH) include deworming programs for school-aged children that are made possible by large-scale drug donations. Decisions on these mass drug administration (MDA) programs currently rely on microscopic examination of clinical specimens to determine the presence of parasite eggs. However, microscopy-based methods are not sensitive to the low-intensity infections that characterize populations that have undergone MDA. Thus, there has been increasing recognition within the schistosomiasis and STH communities of the need for improved diagnostic tools to support late-stage control program decisions, such as when to stop or reduce MDA. Failure to adequately address the need for new diagnostics could jeopardize achievement of the 2020 London Declaration goals. In this report, we assess diagnostic needs and landscape potential solutions and determine appropriate strategies to improve diagnostic testing to support control and elimination programs. Based upon literature reviews and previous input from experts in the schistosomiasis and STH communities, we prioritized two diagnostic use cases for further exploration: to inform MDA-stopping decisions and post-MDA surveillance. To this end, PATH has refined target product profiles (TPPs) for schistosomiasis and STH diagnostics that are applicable to these use cases. We evaluated the limitations of current diagnostic methods with regards to these use cases and identified candidate biomarkers and diagnostics with potential application as new tools. Based on this analysis, there is a need to develop antigen-detecting rapid diagnostic tests (RDTs) with simplified, field-deployable sample preparation for schistosomiasis. Additionally, there is a need for diagnostic tests that are more sensitive than the current methods for STH, which may include either a field-deployable molecular test or a simple, low-cost, rapid antigen-detecting test.

Comparison of Parent Report and Direct Assessment of Child Skills in Toddlers.

PubMed

Miller, Lauren E; Perkins, Kayla A; Dai, Yael G; Fein, Deborah A

2017-09-01

There are unique challenges associated with measuring development in early childhood. Two primary sources of information are used: parent report and direct assessment. Each approach has strengths and weaknesses, particularly when used to identify and diagnose developmental delays. The present study aimed to evaluate consistency between parent report and direct assessment of child skills in toddlers with and without Autism Spectrum Disorder (ASD) across receptive language, expressive language, and fine motor domains. 109 children were evaluated at an average age of two years; data on child skills were collected via parent report and direct assessment. Children were classified into three groups (i.e., ASD, Other Developmental Disorder, or Typical Development) based on DSM-IV-TR diagnosis. Mixed design ANOVAs, with data source as a within subjects factor and diagnostic group as a between subjects factor, were used to assess agreement. Chi square tests of agreement were then used to examine correspondence at the item level. Results suggested that parent report of language and fine motor skills did not significantly differ from direct assessment, and this finding held across diagnostic groups. Item level analyses revealed that, in most cases of significant disagreement, parents reported a skill as present, but it was not seen on direct testing. Results indicate that parents are generally reliable reporters of child language and fine motor abilities in toddlerhood, even when their children have developmental disorders such as ASD. However, the fullest picture may be obtained by using both parent report and direct assessment.

Information-Gathering Patterns Associated with Higher Rates of Diagnostic Error

ERIC Educational Resources Information Center

Delzell, John E., Jr.; Chumley, Heidi; Webb, Russell; Chakrabarti, Swapan; Relan, Anju

2009-01-01

Diagnostic errors are an important source of medical errors. Problematic information-gathering is a common cause of diagnostic errors among physicians and medical students. The objectives of this study were to (1) determine if medical students' information-gathering patterns formed clusters of similar strategies, and if so (2) to calculate the…

Diagnostic grand rounds: a new teaching concept to train diagnostic reasoning.

PubMed

Stieger, Stefan; Praschinger, Andrea; Kletter, Kurt; Kainberger, Franz

2011-06-01

Diagnostic reasoning is a core skill in teaching and learning in undergraduate curricula. Diagnostic grand rounds (DGRs) as a subform of grand rounds are intended to train the students' skills in the selection of appropriate tests and in the interpretation of test results. The aim of this study was to test DGRs for their ability to improve diagnostic reasoning by using a pre-post-test design. During one winter term, all 398 fifth-year students (36.1% male, 63.9% female) solved 23 clinical cases presented in 8 DGRs. In an online questionnaire, a Diagnostic Thinking Inventory (DTI) with 41 items was evaluated for flexibility in thinking and structure of knowledge in memory. Results were correlated with those from a summative multiple-choice knowledge test and of the learning objectives in a logbook. The students' DTI scores in the post-test were significantly higher than those reported in the pre-test. DTI scores at either testing time did not correlate with medical knowledge as assessed by a multiple-choice knowledge test. Abilities acquired during clinical clerkships as documented in a logbook could only account for a small proportion of the increase in the flexibility subscale score. This effect still remained significant after accounting for potential confounders. Establishing DGRs proofed to be an effective way of successfully improving both students' diagnostic reasoning and the ability to select the appropriate test method in routine clinical practice. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

Accuracy of magnetic resonance imaging, magnetic resonance arthrography and computed tomography for the detection of chondral lesions of the knee.

PubMed

Smith, Toby O; Drew, Benjamin T; Toms, Andoni P; Donell, Simon T; Hing, Caroline B

2012-12-01

To assess the diagnostic test accuracy of magnetic resonance imaging (MRI), magnetic resonance arthrography (MRA) and computed tomography arthrography (CTA) for the detection of chondral lesions of the patellofemoral and tibiofemoral joints. A review of published and unpublished literature sources was conducted on 22nd September 2011. All studies assessing the diagnostic test accuracy (sensitivity/specificity) of MRI or MRA or CTA for the assessment of adults with chondral (cartilage) lesions of the knee (tibiofemoral/patellofemoral joints) with surgical comparison (arthroscopic or open) as the reference test were included. Data were analysed through meta-analysis. Twenty-seven studies assessing 2,592 knees from 2,509 patients were included. The findings indicated that whilst presenting a high specificity (0.95-0.99), the sensitivity of MRA, MRI and CTA ranged from 0.70 to 0.80. MRA was superior to MRI and CTA for the detection of patellofemoral joint chondral lesions and that higher field-strength MRI scanner and grade four lesions were more accurately detected compared with lower field-strength and grade one lesions. There appeared no substantial difference in diagnostic accuracy between the interpretation from musculoskeletal and general radiologists when undertaking an MRI review of tibiofemoral and patellofemoral chondral lesions. Specialist radiological imaging is specific for cartilage disease in the knee but has poorer sensitivity to determine the therapeutic options in this population. Due to this limitation, there remains little indication to replace the 'gold-standard' arthroscopic investigation with MRI, MRA or CTA for the assessment of adults with chondral lesions of the knee. II.

Systematic reviews of diagnostic tests in endocrinology: an audit of methods, reporting, and performance.

PubMed

Spencer-Bonilla, Gabriela; Singh Ospina, Naykky; Rodriguez-Gutierrez, Rene; Brito, Juan P; Iñiguez-Ariza, Nicole; Tamhane, Shrikant; Erwin, Patricia J; Murad, M Hassan; Montori, Victor M

2017-07-01

Systematic reviews provide clinicians and policymakers estimates of diagnostic test accuracy and their usefulness in clinical practice. We identified all available systematic reviews of diagnosis in endocrinology, summarized the diagnostic accuracy of the tests included, and assessed the credibility and clinical usefulness of the methods and reporting. We searched Ovid MEDLINE, EMBASE, and Cochrane CENTRAL from inception to December 2015 for systematic reviews and meta-analyses reporting accuracy measures of diagnostic tests in endocrinology. Experienced reviewers independently screened for eligible studies and collected data. We summarized the results, methods, and reporting of the reviews. We performed subgroup analyses to categorize diagnostic tests as most useful based on their accuracy. We identified 84 systematic reviews; half of the tests included were classified as helpful when positive, one-fourth as helpful when negative. Most authors adequately reported how studies were identified and selected and how their trustworthiness (risk of bias) was judged. Only one in three reviews, however, reported an overall judgment about trustworthiness and one in five reported using adequate meta-analytic methods. One in four reported contacting authors for further information and about half included only patients with diagnostic uncertainty. Up to half of the diagnostic endocrine tests in which the likelihood ratio was calculated or provided are likely to be helpful in practice when positive as are one-quarter when negative. Most diagnostic systematic reviews in endocrine lack methodological rigor, protection against bias, and offer limited credibility. Substantial efforts, therefore, seem necessary to improve the quality of diagnostic systematic reviews in endocrinology.

Further statistics in dentistry, Part 5: Diagnostic tests for oral conditions.

PubMed

Petrie, A; Bulman, J S; Osborn, J F

2002-12-07

A diagnostic test is a simple test, sometimes based on a clinical measurement, which is used when the gold-standard test providing a definitive diagnosis of a given condition is too expensive, invasive or time-consuming to perform. The diagnostic test can be used to diagnose a dental condition in an individual patient or as a screening device in a population of apparently healthy individuals.

75 FR 15443 - Advancing the Development of Diagnostic Tests and Biomarkers for Tuberculosis; Public Workshop...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-29

...] Advancing the Development of Diagnostic Tests and Biomarkers for Tuberculosis; Public Workshop; Request for... workshop entitled ``Advancing the Development of Diagnostic Tests and Biomarkers for Tuberculosis (TB... Tuberculosis in the United States, Committee on the Elimination of Tuberculosis in the United States, Division...

Design of a beam emission spectroscopy diagnostic for negative ions radio frequency source SPIDER

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

Zaniol, B.; Pasqualotto, R.; Barbisan, M.

2012-04-15

A facility will be built in Padova (Italy) to develop, commission, and optimize the neutral beam injection system for ITER. The full scale prototype negative ion radio frequency source SPIDER, featuring up to 100 kV acceleration voltage, includes a full set of diagnostics, required for safe operation and to measure and optimize the beam performance. Among them, beam emission spectroscopy (BES) will be used to measure the line integrated beam uniformity, divergence, and neutralization losses inside the accelerator (stripping losses). In the absence of the neutralization stage, SPIDER beam is mainly composed by H{sup -} or D{sup -} particles, accordingmore » to the source filling gas. The capability of a spectroscopic diagnostic of an H{sup -} (D{sup -}) beam relies on the interaction of the beam particles with the background gas particles. The BES diagnostic will be able to acquire the H{sub {alpha}} (D{sub {alpha}}) spectrum from up to 40 lines of sight. The system is capable to resolve stripping losses down to 2 keV and to measure beam divergence with an accuracy of about 10%. The design of this diagnostic is reported, with discussion of the layout and its components, together with simulations of the expected performance.« less

Diagnostic Performance of Narrow Band Imaging for Laryngeal Cancer: A Systematic Review and Meta-analysis.

PubMed

Sun, Changling; Han, Xue; Li, Xiaoying; Zhang, Yayun; Du, Xiaodong

2017-04-01

Objective To evaluate the performance of narrow band imaging (NBI) for the diagnosis of laryngeal cancer and to compare the diagnostic value of NBI with that of white light endoscopy. Data Sources PubMed, Embase, Cochrane Library, and CNKI databases. Review Methods Data analyses were performed with Meta-DiSc. The updated Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess study quality and potential bias. Publication bias was assessed with the Deeks's asymmetry test. The protocol used in this article has been published on PROSPERO and is in accordance with the PRISMA checklist. The registry number for this study is CRD42015025866. Results Six studies including 716 lesions were included in this meta-analysis. The pooled sensitivity, specificity, and diagnostic odds ratio for the NBI diagnosis of laryngeal cancer were 0.94 (95% confidence interval [95% CI]: 0.91-0.96), 0.89 (95% CI: 0.85-0.92), and 142.12 (95% CI: 46.42-435.15), respectively, and the area under receiver operating characteristics curve was 0.97. Among the 6 studies, 3 evaluated the diagnostic value of white light endoscopy, with a sensitivity of 0.81 (95% CI: 0.76-0.86), a specificity of 0.92 (95% CI: 0.88-0.95), and a diagnostic odds ratio of 33.82 (95% CI: 14.76-77.49). The evaluation of heterogeneity, calculated per the diagnostic odds ratio, gave an I 2 of 66%. No marked publication bias ( P = .84) was detected in this meta-analysis. Conclusion The sensitivity of NBI is superior to white light endoscopy, and the potential value of NBI needs to be validated in future studies.

Physical examination for lumbar radiculopathy due to disc herniation in patients with low-back pain.

PubMed

van der Windt, Daniëlle Awm; Simons, Emmanuel; Riphagen, Ingrid I; Ammendolia, Carlo; Verhagen, Arianne P; Laslett, Mark; Devillé, Walter; Deyo, Rick A; Bouter, Lex M; de Vet, Henrica Cw; Aertgeerts, Bert

2010-02-17

Low-back pain with leg pain (sciatica) may be caused by a herniated intervertebral disc exerting pressure on the nerve root. Most patients will respond to conservative treatment, but in carefully selected patients, surgical discectomy may provide faster relief of symptoms. Primary care clinicians use patient history and physical examination to evaluate the likelihood of disc herniation and select patients for further imaging and possible surgery. (1) To assess the performance of tests performed during physical examination (alone or in combination) to identify radiculopathy due to lower lumbar disc herniation in patients with low-back pain and sciatica;(2) To assess the influence of sources of heterogeneity on diagnostic performance. We searched electronic databases for primary studies: PubMed (includes MEDLINE), EMBASE, and CINAHL, and (systematic) reviews: PubMed and Medion (all from earliest until 30 April 2008), and checked references of retrieved articles. We considered studies if they compared the results of tests performed during physical examination on patients with back pain with those of diagnostic imaging (MRI, CT, myelography) or findings at surgery. Two review authors assessed the quality of each publication with the QUADAS tool, and extracted details on patient and study design characteristics, index tests and reference standard, and the diagnostic two-by-two table. We presented information on sensitivities and specificities with 95% confidence intervals (95% CI) for all aspects of physical examination. Pooled estimates of sensitivity and specificity were computed for subsets of studies showing sufficient clinical and statistical homogeneity. We included 16 cohort studies (median N = 126, range 71 to 2504) and three case control studies (38 to100 cases). Only one study was carried out in a primary care population. When used in isolation, diagnostic performance of most physical tests (scoliosis, paresis or muscle weakness, muscle wasting, impaired reflexes, sensory deficits) was poor. Some tests (forward flexion, hyper-extension test, and slump test) performed slightly better, but the number of studies was small. In the one primary care study, most tests showed higher specificity and lower sensitivity compared to other settings.Most studies assessed the Straight Leg Raising (SLR) test. In surgical populations, characterized by a high prevalence of disc herniation (58% to 98%), the SLR showed high sensitivity (pooled estimate 0.92, 95% CI: 0.87 to 0.95) with widely varying specificity (0.10 to 1.00, pooled estimate 0.28, 95% CI: 0.18 to 0.40). Results of studies using imaging showed more heterogeneity and poorer sensitivity. The crossed SLR showed high specificity (pooled estimate 0.90, 95% CI: 0.85 to 0.94) with consistently low sensitivity (pooled estimate 0.28, 95% CI: 0.22 to 0.35).Combining positive test results increased the specificity of physical tests, but few studies presented data on test combinations. When used in isolation, current evidence indicates poor diagnostic performance of most physical tests used to identify lumbar disc herniation. However, most findings arise from surgical populations and may not apply to primary care or non-selected populations. Better performance may be obtained when tests are combined.

Predictors of Inappropriate Use of Diagnostic Tests and Management of Bronchiolitis

PubMed Central

Sarmiento, Lorena; Rojas-Soto, Gladys E.

2017-01-01

Background The aim of the present study was to determine predictors of inappropriate use of diagnostic tests and management of bronchiolitis in a population of hospitalized infants. Methods In an analytical cross-sectional study, we determined independent predictors of the inappropriate use of diagnostic tests and management of bronchiolitis in a population of hospitalized infants. We defined a composite outcome score as the main outcome variable. Results Of the 303 included patients, 216 (71.3%) experienced an inappropriate use of diagnostic tests and treatment of bronchiolitis. After controlling for potential confounders, it was found that atopic dermatitis (OR 5.30; CI 95% 1.14–24.79; p = 0.034), length of hospital stay (OR 1.48; CI 95% 1.08–2.03; p = 0.015), and the number of siblings (OR 1.92; CI 95% 1.13–3.26; p = 0.015) were independent predictors of an inappropriate use of diagnostic tests and treatment of the disease. Conclusions Inappropriate use of diagnostic tests and treatment of bronchiolitis was a highly prevalent outcome in our population of study. Participants with atopic dermatitis, a longer hospital stay, and a greater number of siblings were at increased risk for inappropriate use of diagnostic tests and management of the disease. PMID:28758127

Rapid diagnostic tests to improve treatment of malaria and other febrile illnesses: patient randomised effectiveness trial in primary care clinics in Afghanistan

PubMed Central

Mikhail, Amy; Mayan, Ismail; Cundill, Bonnie; Anwar, Mohammed; Bakhtash, Sayed Habib; Mohammed, Nader; Rahman, Habib; Zekria, Rohullah; Whitty, Christopher J M; Rowland, Mark

2014-01-01

Objective To assess the impact of rapid diagnostic tests on the diagnostic accuracy and treatment of malaria and non-severe fever in an Asian setting. Design Patient randomised trial in primary level clinics. Setting Two areas of Afghanistan where Plasmodium vivax and Plasmodium falciparum are endemic; one area with moderate transmission (eastern region) and one with low transmission (northern region). Participants 5794 patients of all ages with suspected malaria enrolled by 80 clinicians in 22 clinics. Interventions Malaria rapid diagnostic tests were compared with clinical diagnosis where no parasite diagnostic test was available, longer established field microscopy, and recently introduced microscopy. Main outcome measures Proportion of patients appropriately treated with an antimalarial, defined as patients with P vivax who received chloroquine, patients with P falciparum who received artemisinin based combination therapy, and patients with no malaria parasites who did not receive an antimalarial. Secondary outcomes included diagnostic test accuracy and the proportion of patients negative for malaria who received antibiotics and antimalarials. Results In the low transmission area, comparing rapid diagnostic tests with clinical diagnosis, 65% (212/325) versus 12% (40/321) of febrile patients were appropriately treated for malaria (adjusted odds ratio 92.7, 95% confidence interval 12.4 to 694.1, P<0.001). The proportion of patients who were negative for malaria and received an antibiotic was 57% (185/325) in the rapid diagnostic test arm compared with 14% (46/321) in the clinical diagnosis arm (16.9, 3.8 to 75.4, P<0.001). In the comparison of rapid diagnostic test with microscopy in the moderate transmission area, 83.6% (1696/2028) versus 76.3% (1512/1983) of patients were appropriately treated for malaria (1.70, 1.30 to 2.23, P<0.001). A higher proportion of P falciparum cases received appropriate treatment with artemisinin based combination therapy when malaria was diagnosed by rapid diagnostic test (82%, 58/71 v 32%, 24/76; 9.2, 3.88 to 21.66, P<0.001). Conclusions In South and central Asian regions of low to moderate malaria transmission where clinics lack capacity for diagnosis with rapid diagnostic tests or microscopy, the introduction of the tests should be considered to improve clinical care, reduce the overuse of antimalarials, and improve disease surveillance. PMID:24948695

Variability in the diagnostic performance of a bedside rapid diagnostic influenza test over four epidemic seasons in a pediatric emergency department.

PubMed

Avril, E; Lacroix, S; Vrignaud, B; Moreau-Klein, A; Coste-Burel, M; Launay, E; Gras-Le Guen, C

2016-07-01

We wanted to determine the diagnostic performance of a rapid influenza diagnostic test (RIDT) used bedside in a pediatric emergency department (PED). This was a prospective study over four consecutive winters (2009-2013), comparing the results of a RIDT (QuickVue®) with RT-PCR in children admitted to a PED. Among the 764 children included, we did not observe any significant differences in the diagnostic performance of RIDT except during the H1N1 pandemic. The overall sensitivity of the test was 0.82; the specificity 0.98; the positive and negative likelihood ratios 37.8 and 0.19. The positive and negative post-test probabilities of infection were 98% and 17%. The diagnostic performance was increased for influenza B cases (P = 0.03). RIDTs are suitable for use every winter with few differences in its diagnostic value, except during specific pandemic periods. This test could limit unnecessary complementary exams and guide the prescription of antivirals during influenza epidemic periods in PEDs. Copyright © 2016. Published by Elsevier Inc.

[Methods for evaluating diagnostic tests in Enfermedades Infecciosas y Microbiología Clínica].

PubMed

Ramos, J M; Hernández, I

1998-04-01

In the field of infectious diseases and clinical microbiology, the evaluation of diagnostic tests (DT) is an important research area. The specific difficulties of this type of research has motivated that have not caught the severity methodological of others areas of clinical research. This article try to asses and characterize the methodology of articles about DT published in Enfermedades Infecciosas y Microbiología Clínica (EIMC) journal. Forty-five articles was selected in the EIMC journal during the 1990-1996 period, because of determinate the sensitivity and specificity of different DT. Methodological standards, extensively accepted was used. In all of articles, except one (98%) the gold standard was specified yours use, however in 4 studies (9%) include the DT in the gold standard (incorporation bias). The correct description of DT was reported in 75% of cases, but only in 11% cases the reproducibility of test was evaluated. The description of source of reference population, standard of inclusion and spectrum of composition was described in 58, 33 and 40% of articles, respectively. In 33% of studies presented workup bias, only 6% commented blind-analysis of results, and 11% presented indeterminate test results. Half of the studies reported test indexes for clinical subgroups, only one article (2%) provided numerical precision for test indexes, and only 7% reported receiver operating characteristics curves. The methodological quality of DT research in the EIMC journal may improve in different aspects of design and presentation of results.

42 CFR 414.509 - Reconsideration of basis for and amount of payment for a new clinical diagnostic laboratory test.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) or § 414.509(a)(3) that the basis for payment for a new test will be gapfilling, CMS posts interim... for a new clinical diagnostic laboratory test. 414.509 Section 414.509 Public Health CENTERS FOR... FOR PART B MEDICAL AND OTHER HEALTH SERVICES Payment for New Clinical Diagnostic Laboratory Tests...

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

Nam, Y. B., E-mail: southub@postech.ac.kr; Yun, G. S.; Lee, D. J.

Electron cyclotron emission imaging (ECEI) diagnostic on Korean Superconducting Tokamak Advanced Research utilizes quasi-optical heterodyne-detection method to measure 2D (vertical and radial) T{sub e} fluctuations from two toroidally separated poloidal cross section of the plasma. A cylindrical lens local oscillator (LO) optics with optical path length (OPL) 2–2.5 m has been used in the current ECEI system to couple the LO source to the 24 vertically aligned array of ECE detectors. For efficient and compact LO optics employing the Powell lens is proposed so that the OPL of the LO source is significantly reduced from ∼2.0 m to 0.4 mmore » with new optics. The coupling efficiency of the LO source is expected to be improved especially at the edge channels. Results from the optical simulation together with the laboratory test of the prototype optics will be discussed in this paper.« less

Development of visible spectroscopy diagnostics for W sources assessment in WEST

NASA Astrophysics Data System (ADS)

Meyer, O.; Jones, O. M.; Giacalone, J. C.; Pascal, J. Y.; Raulin, D.; Xu, H.; Aumeunier, M. H.; Baude, R.; Escarguel, A.; Gil, C.; Harris, J. H.; Hatchressian, J.-C.; Klepper, C. C.; Larroque, S.; Lotte, Ph.; Moreau, Ph.; Pégourié, B.; Vartanian, S.

2016-11-01

The present work concerns the development of a W sources assessment system in the framework of the tungsten-W environment in steady state tokamak project that aims at equipping the existing Tore Supra device with a tungsten divertor in order to test actively cooled tungsten Plasma Facing Components (PFCs) in view of preparing ITER operation. The goal is to assess W sources and D recycling with spectral, spatial, and temporal resolution adapted to the PFCs observed. The originality of the system is that all optical elements are installed in the vacuum vessel and compatible with steady state operation. Our system is optimized to measure radiance as low as 1016 Ph/(m2 s sr). A total of 240 optical fibers will be deployed to the detection systems such as the "Filterscope," developed by Oak Ridge National Laboratory (USA) and consisting of photomultiplier tubes and filters, or imaging spectrometers dedicated to Multiview analysis.

Urinary biomarkers for the non-invasive diagnosis of endometriosis.

PubMed

Liu, Emily; Nisenblat, Vicki; Farquhar, Cindy; Fraser, Ian; Bossuyt, Patrick M M; Johnson, Neil; Hull, M Louise

2015-12-23

About 10% of reproductive-aged women suffer from endometriosis which is a costly chronic disease that causes pelvic pain and subfertility. Laparoscopy is the 'gold standard' diagnostic test for endometriosis, but it is expensive and carries surgical risks. Currently, there are no simple non-invasive or minimally-invasive tests available in clinical practice that accurately diagnoses endometriosis. 1. To provide summary estimates of the diagnostic accuracy of urinary biomarkers for the diagnosis of pelvic endometriosis compared to surgical diagnosis as a reference standard.2. To assess the diagnostic utility of biomarkers that could differentiate ovarian endometrioma from other ovarian masses.Urinary biomarkers were evaluated as replacement tests for surgical diagnosis and as triage tests to inform decisions to undertake surgery for endometriosis. The searches were not restricted to particular study design, language or publication dates. We searched the following databases to 20 April - 31 July 2015: CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO, Web of Science, LILACS, OAIster, TRIP and ClinicalTrials.gov (trial register). MEDION, DARE, and PubMed were also searched to identify reviews and guidelines as reference sources of potentially relevant studies. Recently published papers not yet indexed in the major databases were also sought. The search strategy incorporated words in the title, abstract, text words across the record and the medical subject headings (MeSH) and was modified for each database. Published peer-reviewed, randomised controlled or cross-sectional studies of any size were considered, which included prospectively collected samples from any population of reproductive-aged women suspected of having one or more of the following target conditions: ovarian, peritoneal or deep infiltrating endometriosis (DIE). We included studies comparing the diagnostic test accuracy of one or more urinary biomarkers with surgical visualisation of endometriotic lesions. Two authors independently collected and performed a quality assessment of the data from each study. For each diagnostic test, the data were classified as positive or negative for the surgical detection of endometriosis and sensitivity and specificity estimates were calculated. If two or more tests were evaluated in the same cohort, each was considered as a separate data set. The bivariate model was used to obtain pooled estimates of sensitivity and specificity whenever sufficient data sets were available. The predetermined criteria for a clinically useful urine test to replace diagnostic surgery was one with a sensitivity of 94% and a specificity of 79% to detect endometriosis. The criteria for triage tests were set at sensitivity of equal or greater than 95% and specificity of equal or greater than 50%, which in case of negative result rules out the diagnosis (SnOUT test) or sensitivity of equal or greater than 50% with specificity of equal or greater than 95%, which in case of positive result rules the diagnosis in (SpIN test). We included eight studies involving 646 participants, most of which were of poor methodological quality. The urinary biomarkers were evaluated either in a specific phase of menstrual cycle or irrespective of the cycle phase. Five studies evaluated the diagnostic performance of four urinary biomarkers for endometriosis, including three biomarkers distinguishing women with and without endometriosis (enolase 1 (NNE); vitamin D binding protein (VDBP); and urinary peptide profiling); and one biomarker (cytokeratin 19 (CK 19)) showing no significant difference between the two groups. All of these biomarkers were assessed in small individual studies and could not be statistically evaluated in a meaningful way. None of the biomarkers met the criteria for a replacement test or a triage test. Three studies evaluated three biomarkers that did not differentiate women with endometriosis from disease-free controls. There was insufficient evidence to recommend any urinary biomarker for use as a replacement or triage test in clinical practice for the diagnosis of endometriosis. Several urinary biomarkers may have diagnostic potential, but require further evaluation before being introduced into routine clinical practice. Laparoscopy remains the gold standard for the diagnosis of endometriosis, and diagnosis of endometriosis using urinary biomarkers should only be undertaken in a research setting.

Developing energy and momentum conceptual survey (EMCS) with four-tier diagnostic test items

NASA Astrophysics Data System (ADS)

Afif, Nur Faadhilah; Nugraha, Muhammad Gina; Samsudin, Achmad

2017-05-01

Students' conceptions of work and energy are important to support the learning process in the classroom. For that reason, a diagnostic test instrument is needed to diagnose students' conception of work and energy. As a result, the researcher decided to develop Energy and Momentum Conceptual Survey (EMCS) instrument test into four-tier test diagnostic items. The purpose of this research is organized as the first step of four-tier test-formatted EMCS development as one of diagnostic test instruments on work and Energy. The research method used the 4D model (Defining, Designing, Developing and Disseminating). The instrument developed has been tested to 39 students in one of Senior High Schools. The resulting research showed that four-tier test-formatted EMCS is able to diagnose students' conception level of work and energy concept. It can be concluded that the development of four-tier test-formatted EMCS is one of potential diagnostic test instruments that able to obtain the category of students who understand concepts, misconceptions and do not understand about Work and Energy concept at all.

Autoimmune diagnostics: the technology, the strategy and the clinical governance.

PubMed

Bizzaro, Nicola; Tozzoli, Renato; Villalta, Danilo

2015-02-01

In recent years, there has been a profound change in autoimmune diagnostics. From long, tiring and inaccurate manual methods, the art of diagnostics has turned to modern, rapid and automated technology. New antibody tests have been developed, and almost all autoimmune diseases now have some specific diagnostic markers. The current need to make the most of available economic and human resources has led to the production of diagnostic algorithms and guidelines designated for optimal strategic use of the tests and to increase the diagnostic appropriateness. An important role in this scenario was assumed by the laboratory autoimmunologist, whose task is not only to govern the analytical phase, but also to help clinicians in correctly choosing the most suitable test for each clinical situation and provide consultancy support. In this review, we summarize recent advances in technology, describe the diagnostic strategies and highlight the current role of the laboratory autoimmunologist in the clinical governance of autoimmune diagnostics.

[Companion diagnostics "POTELIGEO TEST IHC/FCM" used with "POTELIGEO" (mogamulizumab) for adult T-cell leukemia-lymphoma (ATL) treatment].

PubMed

Goami, Takeshi

2014-05-01

Personalized medicine offers the best treatment for individual patients, it is important for an IVD manufacturer to develop companion diagnostics in parallel with the development of new drugs through close cooperation with drug companies, and supply diagnostics companies with new drugs for physicians and patients. We received approval for a premarket approval application (PMA) for two in vitro diagnostic ("IVD") reagents, POTELIGEO TEST IHC and POTELIGEO TEST FCM ("POTELIGEO TEST"), in March 2012, and subsequently launched POTELIGEO TEST in May 2012. POTELIGEO TEST is a companion diagnostic used with POTELIGEO for which Kyowa Hakko Kirin has a new drug application (NDA) that was approved in March 2012, and is designed to help physicians identify appropriate subpopulations of adult T-cell leukemia-lymphoma(ATL) patients who are most likely to respond to POTELIGEO 20 mg (mogamulizumab) Injection ("POTELIGEO").

WE-AB-206-00: Diagnostic QA/QC Hands-On Workshop

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

NONE

The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. The goal of this ultrasound hands-on workshop is to demonstrate quality control (QC) testing in diagnostic ultrasound and to provide updates in ACR ultrasound accreditation requirements. The first half of this workshop will include two presentations reviewing diagnostic ultrasound QA/QC and ACR ultrasound accreditation requirements. The second half of the workshop will include live demonstrations of basic QC tests. An array of ultrasound testing phantoms and ultrasound scanners will be available for attendees to learn diagnostic ultrasound QC in a hands-on environmentmore » with live demonstrations and on-site instructors. The targeted attendees are medical physicists in diagnostic imaging. Learning Objectives: Gain familiarity with common elements of a QA/QC program for diagnostic ultrasound imaging dentify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools Learn ACR ultrasound accreditation requirements Jennifer Walter is an employee of American College of Radiology on Ultrasound Accreditation.« less

BATMAN beam properties characterization by the beam emission spectroscopy diagnostic

NASA Astrophysics Data System (ADS)

Bonomo, F.; Ruf, B.; Barbisan, M.; Cristofaro, S.; Schiesko, L.; Fantz, U.; Franzen, P.; Pasqualotto, R.; Riedl, R.; Serianni, G.; Wünderlich, D.

2015-04-01

The ITER neutral beam heating systems are based on the production and acceleration of negative ions (H/D) up to 1 MV. The requirements for the beam properties are strict: a low core beam divergence (< 0.4 °) together with a low source pressure (≤ 0.3 Pa) would permit to reduce the ion losses along the beamline, keeping the stripping particle losses below 30%. However, the attainment of such beam properties is not straightforward. At IPP, the negative ion source testbed BATMAN (BAvarian Test MAchine for Negative ions) allows for deepening the knowledge of the determination of the beam properties. One of the diagnostics routinely used to this purpose is the Beam Emission Spectroscopy (BES): the Hα light emitted in the beam is detected and the corresponding spectra are evaluated to estimate the beam divergence and the stripping losses. The BES number of lines of sight in BATMAN has been recently increased: five horizontal lines of sight providing a vertical profile of the beam permit to characterize the negative ion beam properties in relation to the source parameters. Different methods of Hα spectra analysis are here taken into account and compared for the estimation of the beam divergence and the amount of stripping. In particular, to thoroughly study the effect of the space charge compensation on the beam divergence, an additional hydrogen injection line has been added in the tank, which allows for setting different background pressure values (one order of magnitude, from about 0.04 Pa up to the source pressure) in the beam drift region.

PIP-II Injector Test Warm Front End: Commissioning Update

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

Prost, Lionel R.; et al.

The Warm Front End (WFE) of the Proton Improvement Plan II Injector Test [1] at Fermilab has been constructed to its full length. It includes a 15-mA DC, 30-keV H- ion source, a 2 m-long Low Energy Beam Transport (LEBT) with a switching dipole magnet, a 2.1 MeV CW RFQ, followed by a Medium Energy Beam Transport (MEBT) with various diagnostics and a dump. This report presents the commissioning status, focusing on beam measurements in the MEBT. In particular, a beam with the parameters required for injection into the Booster (5 mA, 0.55 ms macro-pulse at 20 Hz) was transportedmore » through the WFE.« less

Evaluation of Machine Learning and Rules-Based Approaches for Predicting Antimicrobial Resistance Profiles in Gram-negative Bacilli from Whole Genome Sequence Data.

PubMed

Pesesky, Mitchell W; Hussain, Tahir; Wallace, Meghan; Patel, Sanket; Andleeb, Saadia; Burnham, Carey-Ann D; Dantas, Gautam

2016-01-01

The time-to-result for culture-based microorganism recovery and phenotypic antimicrobial susceptibility testing necessitates initial use of empiric (frequently broad-spectrum) antimicrobial therapy. If the empiric therapy is not optimal, this can lead to adverse patient outcomes and contribute to increasing antibiotic resistance in pathogens. New, more rapid technologies are emerging to meet this need. Many of these are based on identifying resistance genes, rather than directly assaying resistance phenotypes, and thus require interpretation to translate the genotype into treatment recommendations. These interpretations, like other parts of clinical diagnostic workflows, are likely to be increasingly automated in the future. We set out to evaluate the two major approaches that could be amenable to automation pipelines: rules-based methods and machine learning methods. The rules-based algorithm makes predictions based upon current, curated knowledge of Enterobacteriaceae resistance genes. The machine-learning algorithm predicts resistance and susceptibility based on a model built from a training set of variably resistant isolates. As our test set, we used whole genome sequence data from 78 clinical Enterobacteriaceae isolates, previously identified to represent a variety of phenotypes, from fully-susceptible to pan-resistant strains for the antibiotics tested. We tested three antibiotic resistance determinant databases for their utility in identifying the complete resistome for each isolate. The predictions of the rules-based and machine learning algorithms for these isolates were compared to results of phenotype-based diagnostics. The rules based and machine-learning predictions achieved agreement with standard-of-care phenotypic diagnostics of 89.0 and 90.3%, respectively, across twelve antibiotic agents from six major antibiotic classes. Several sources of disagreement between the algorithms were identified. Novel variants of known resistance factors and incomplete genome assembly confounded the rules-based algorithm, resulting in predictions based on gene family, rather than on knowledge of the specific variant found. Low-frequency resistance caused errors in the machine-learning algorithm because those genes were not seen or seen infrequently in the test set. We also identified an example of variability in the phenotype-based results that led to disagreement with both genotype-based methods. Genotype-based antimicrobial susceptibility testing shows great promise as a diagnostic tool, and we outline specific research goals to further refine this methodology.

Comparative Diagnostic Accuracy of the ACE-III, MIS, MMSE, MoCA, and RUDAS for Screening of Alzheimer Disease.

PubMed

Matías-Guiu, Jordi A; Valles-Salgado, María; Rognoni, Teresa; Hamre-Gil, Frank; Moreno-Ramos, Teresa; Matías-Guiu, Jorge

2017-01-01

Our aim was to evaluate and compare the diagnostic properties of 5 screening tests for the diagnosis of mild Alzheimer disease (AD). We conducted a prospective and cross-sectional study of 92 patients with mild AD and of 68 healthy controls from our Department of Neurology. The diagnostic properties of the following tests were compared: Mini-Mental State Examination (MMSE), Addenbrooke's Cognitive Examination III (ACE-III), Memory Impairment Screen (MIS), Montreal Cognitive Assessment (MoCA), and Rowland Universal Dementia Assessment Scale (RUDAS). All tests yielded high diagnostic accuracy, with the ACE-III achieving the best diagnostic properties. The area under the curve was 0.897 for the ACE-III, 0.889 for the RUDAS, 0.874 for the MMSE, 0.866 for the MIS, and 0.856 for the MoCA. The Mini-ACE score from the ACE-III showed the highest diagnostic capacity (area under the curve 0.939). Memory scores of the ACE-III and of the RUDAS showed a better diagnostic accuracy than those of the MMSE and of the MoCA. All tests, especially the ACE-III, conveyed a higher diagnostic accuracy in patients with full primary education than in the less educated group. Implementing normative data improved the diagnostic accuracy of the ACE-III but not that of the other tests. The ACE-III achieved the highest diagnostic accuracy. This better discrimination was more evident in the more educated group. © 2017 S. Karger AG, Basel.

Short-Term Outcomes of Screening Mammography Using Computer-Aided Detection

PubMed Central

Fenton, Joshua J.; Xing, Guibo; Elmore, Joann G.; Bang, Heejung; Chen, Steven L.; Lindfors, Karen K.; Baldwin, Laura-Mae

2013-01-01

Background Computer-aided detection (CAD) has rapidly diffused into screening mammography practice despite limited and conflicting data on its clinical effect. Objective To determine associations between CAD use during screening mammography and the incidence of ductal carcinoma in situ (DCIS) and invasive breast cancer, invasive cancer stage, and diagnostic testing. Design Retrospective cohort study. Setting Medicare program. Participants Women aged 67 to 89 years having screening mammography between 2001 and 2006 in U.S. SEER (Surveillance, Epidemiology and End Results) regions (409 459 mammograms from 163 099 women). Measurements Incident DCIS and invasive breast cancer within 1 year after mammography, invasive cancer stage, and diagnostic testing within 90 days after screening among women without breast cancer. Results From 2001 to 2006, CAD prevalence increased from 3.6% to 60.5%. Use of CAD was associated with greater DCIS incidence (adjusted odds ratio [OR], 1.17 [95% CI, 1.11 to 1.23]) but no difference in invasive breast cancer incidence (adjusted OR, 1.00 [CI, 0.97 to 1.03]). Among women with invasive cancer, CAD was associated with greater likelihood of stage I to II versus III to IV cancer (adjusted OR, 1.27 [CI, 1.14 to 1.41]). In women without breast cancer, CAD was associated with increased odds of diagnostic mammography (adjusted OR, 1.28 [CI, 1.27 to 1.29]), breast ultrasonography (adjusted OR, 1.07 [CI, 1.06 to 1.09]), and breast biopsy (adjusted OR, 1.10 [CI, 1.08 to 1.12]). Limitation Short follow-up for cancer stage, potential unmeasured confounding, and uncertain generalizability to younger women. Conclusion Use of CAD during screening mammography among Medicare enrollees is associated with increased DCIS incidence, the diagnosis of invasive breast cancer at earlier stages, and increased diagnostic testing among women without breast cancer. Primary Funding Source Center for Healthcare Policy and Research, University of California, Davis. PMID:23588746

Medical X-ray sources now and for the future

NASA Astrophysics Data System (ADS)

Behling, Rolf

2017-11-01

This paper focuses on the use of X-rays in their largest field of application: medical diagnostic imaging and image-guided therapy. For this purpose, vacuum electronics in the form of X-ray tubes as the source of bremsstrahlung (braking radiation) have been the number one choice for X-ray production in the range of photon energies between about 16 keV for mammography and 150 keV for general radiography. Soft tissue on one end and bony structures on the other are sufficiently transparent and the contrast delivered by difference of absorption is sufficiently high for this spectral range. The dominance of X-ray tubes holds even more than 120 years after Conrad Roentgen's discovery of the bremsstrahlung mechanism. What are the specifics of current X-ray tubes and their medical diagnostic applications? How may the next available technology at or beyond the horizon look like? Can we hope for substantial game changers? Will flat panel sources, less expensive X-ray "LED's", compact X-ray Lasers, compact synchrotrons or equivalent X-ray sources appear in medical diagnostic imaging soon? After discussing the various modalities of imaging systems and their sources of radiation, this overview will briefly touch on the physics of bremsstrahlung generation, key characteristics of X-ray tubes, and material boundary conditions, which restrict performance. It will discuss the deficits of the bremsstrahlung technology and try to sketch future alternatives and their prospects of implementation in medical diagnostics.

WE-AB-206-03: Workshop

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

Lu, Z.

The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. The goal of this ultrasound hands-on workshop is to demonstrate quality control (QC) testing in diagnostic ultrasound and to provide updates in ACR ultrasound accreditation requirements. The first half of this workshop will include two presentations reviewing diagnostic ultrasound QA/QC and ACR ultrasound accreditation requirements. The second half of the workshop will include live demonstrations of basic QC tests. An array of ultrasound testing phantoms and ultrasound scanners will be available for attendees to learn diagnostic ultrasound QC in a hands-on environmentmore » with live demonstrations and on-site instructors. The targeted attendees are medical physicists in diagnostic imaging. Learning Objectives: Gain familiarity with common elements of a QA/QC program for diagnostic ultrasound imaging dentify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools Learn ACR ultrasound accreditation requirements Jennifer Walter is an employee of American College of Radiology on Ultrasound Accreditation.« less

Selling biotechnology in the dental medicine marketplace: the OmniGene Diagnostics DNA probe tests for periodontal pathogens.

PubMed

Van Arsdell, S W; DiFronzo, F; Backman, K C; Mahler, P H

1996-09-01

OmniGene Diagnostics, Inc. has applied the principles of genetic engineering to develop species-specific DNA probe tests for eight periodontal pathogens (Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetem-comitans, Fusobacterium nucleatum, Eikenella corrodens, Campylobacter rectus, Bacteroides forsythus, and Treponema denticola). The test requires minimal effort on the part of the clinician: subgingival plaque samples are collected from the patient and sent through the mail for analysis by OmniGene Diagnostics' fully licensed clinical reference laboratory. Results are transmitted to the practitioner by phone, fax, or mail. The use of diagnostic tests for periodontal pathogens is a relatively new concept in dentistry and acceptance of the OmniGene Diagnostics tests by the dental marketplace has been slower than anticipated. OmniGene Diagnostics' challenge for the future is to persuade the dental community that monitoring periodontal pathogen levels, as well as other clinical indicators of disease, is essential to providing optimal care to the periodontitis patient.

Diagnostic Testing at UK Universities: An E-Mail Survey

ERIC Educational Resources Information Center

Gillard, Jonathan; Levi, Margaret; Wilson, Robert

2010-01-01

In July 2009, an e-mail survey was sent to various UK universities to gain information regarding current practices concerning mathematics diagnostic testing, and to provide an update from the review "Diagnostic Testing for Mathematics" published by the LTSN MathsTEAM Project in 2003. A total of 38 university departments were contacted…

30 CFR 250.524 - When am I required to take action from my casing diagnostic test?

Code of Federal Regulations, 2010 CFR

2010-07-01

... casing diagnostic test; (c) Any well that has demonstrated tubing/casing, tubing/riser, casing/casing... casing diagnostic test? 250.524 Section 250.524 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT... Gas Well-Completion Operations Casing Pressure Management § 250.524 When am I required to take action...

Diagnostic Testing Package DX v 2.0 Technical Specification. Methodology Project.

ERIC Educational Resources Information Center

McArthur, David

This paper contains the technical specifications, schematic diagrams, and program printout for a computer software package for the development and administration of diagnostic tests. The second version of the Diagnostic Testing Package DX consists of a PASCAL-based set of modules located in two main programs: (1) EDITTEST creates, modifies, and…

Diagnostic testing.

PubMed

Brewer, D E

2000-09-01

The results of cardiac tests must always be interpreted through the lens of pretest probabilities created by the history and the physical examination. Tests should be chosen with a clear diagnostic and prognostic purpose in mind. A clear understanding of the relationship between the history and physical examination and more technologic diagnostic testing improves the primary care physician's ability to evaluate potential cardiac disease in an efficient and cost-effective manner.

42 CFR 414.509 - Reconsideration of basis for and amount of payment for a new clinical diagnostic laboratory test.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) or § 414.509(a)(3) that the basis for payment for a new test will be gapfilling, CMS posts interim... for a new clinical diagnostic laboratory test. 414.509 Section 414.509 Public Health CENTERS FOR... Laboratory Tests § 414.509 Reconsideration of basis for and amount of payment for a new clinical diagnostic...

Effects of a Web-Based Decision Aid Regarding Diagnostic Self-Testing. A Single-Blind Randomized Controlled Trial

ERIC Educational Resources Information Center

Ickenroth, Martine H. P.; Grispen, J. E. J.; de Vries, N. K.; Dinant, G. J.; Ronda, G.; van der Weijden, T.

2016-01-01

Currently, there are many diagnostic self-tests on body materials available to consumers. The aim of this study was to assess the effect of an online decision aid on diagnostic self-testing for cholesterol and diabetes on knowledge among consumers with an intention to take these tests. A randomized controlled trial was designed. A total of 1259…

Cheyletiella infestation in the dog: observations on diagnostic methods and clinical signs.

PubMed

Saevik, B K; Bredal, W; Ulstein, T L

2004-10-01

The aims of this study were to evaluate the ability of diagnostic methods to detect naturally occurring Cheyletiella infestation in dogs, and to quantify and relate the number of mites and eggs present to clinical signs. Privately owned dogs with skin problems were eligible for inclusion in the study. Four diagnostic tests were performed on each dog in the following order: tape impression, hair plucking, skin scraping and vacuum cleaning. Dogs with positive test results for Cheyletiella infestation in at least one of the tests under evaluation were included in the study (n=27). The severity of pruritus and scaling was graded on a four-point fixed scale. The diagnostic findings in vacuum cleaning samples provided a semiquantitative measure of the grade of infestation. The vacuum cleaning test gave a positive test result in all dogs and was significantly more efficient than the other tests evaluated (P<0.01). The number of diagnostic findings varied considerably among the different vacuum samples. No significant relationship between the number of diagnostic findings and severity of clinical signs was detected.

Self-Reported HIV-Positive Status But Subsequent HIV-Negative Test Result Using Rapid Diagnostic Testing Algorithms Among Seven Sub-Saharan African Military Populations

DTIC Science & Technology

2017-07-07

RESEARCH ARTICLE Self-reported HIV-positive status but subsequent HIV-negative test result using rapid diagnostic testing algorithms among seven sub...America * judith.harbertson.ctr@mail.mil Abstract HIV rapid diagnostic tests (RDTs) combined in an algorithm are the current standard for HIV diagnosis...in many sub-Saharan African countries, and extensive laboratory testing has con- firmed HIV RDTs have excellent sensitivity and specificity. However

Variation in Women's Understanding of Prenatal Testing.

PubMed

Bryant, Allison S; Norton, Mary E; Nakagawa, Sanae; Bishop, Judith T; Pena, Sherri; Gregorich, Steven E; Kuppermann, Miriam

2015-06-01

To investigate women's understanding of prenatal testing options and of their own experience with screening, diagnostic genetic testing, or both. This was a secondary analysis of data from a randomized controlled trial of enhanced information and values clarification regarding prenatal genetic testing in the absence of financial barriers to testing. Women in the third trimester of pregnancy were asked whether they had discussed prenatal genetic testing with their health care providers, whether they understood this testing was optional, and whether they had undergone testing during their pregnancy. Multivariable logistic regression models were fit to determine independent predictors of these outcomes. Data were available from 710 study participants. Discussions about screening tests were reported by 654 participants (92%); only 412 (58%) reported discussing diagnostic testing. That screening and diagnostic testing were optional was evident to approximately two thirds of women (n=470 and 455, respectively). Recall of actual tests undergone was correct for 626 (88%) for screening and for 700 (99%) for diagnostic testing. Racial, ethnic and socioeconomic variation existed in the understanding of whether screening and diagnostic tests were optional and in the correct recall of whether screening had been undertaken in the current pregnancy. In the usual care group, women receiving care in low-income settings were less likely to recall being offered diagnostic testing (adjusted odds ratio 0.23 [0.14-0.39]). Disparities exist in women's recall of prenatal genetic testing discussions and their understanding of their own experience. Interventions that explain testing options to women and help clarify their preferences may help to eliminate these differences.

New laser sources for clinical treatment and diagnostics of neonatal jaundice

NASA Astrophysics Data System (ADS)

Hamza, Mostafa; El-Ahl, Mohammad H. S.; Hamza, Ahmad M.

2001-06-01

An elevated serum bilirubin concentration in the newborn infant presents a therapeutic as well as a diagnostic problem to the physician. It has long been recognized that high levels of bilirubin cause irreversible brain damage and even death. The authors introduce the use of semiconductor diode lasers and diode-pumped solid-state lasers that can be used for solving such diagnostic and therapeutic problems. These new laser sources can improve the ergonomics of using laser, enhance performance capabilities and reduce the cost of employing laser energy to pump bilirubin out of an infant's body. The choice of laser wavelengths follows the principles of bilirubinometry and phototherapy of neonatal jaundice. The wide spread use of these new laser sources for clinical monitoring and treatment of neonatal hyperbilirubinemia will be made possible as each incremental or quantum jump cost reduction is achieved. Our leading clinical experience as well as the selection rules of laser wavelengths will be presented.

Quality and reporting of diagnostic accuracy studies in TB, HIV and malaria: evaluation using QUADAS and STARD standards.

PubMed

Fontela, Patricia Scolari; Pant Pai, Nitika; Schiller, Ian; Dendukuri, Nandini; Ramsay, Andrew; Pai, Madhukar

2009-11-13

Poor methodological quality and reporting are known concerns with diagnostic accuracy studies. In 2003, the QUADAS tool and the STARD standards were published for evaluating the quality and improving the reporting of diagnostic studies, respectively. However, it is unclear whether these tools have been applied to diagnostic studies of infectious diseases. We performed a systematic review on the methodological and reporting quality of diagnostic studies in TB, malaria and HIV. We identified diagnostic accuracy studies of commercial tests for TB, malaria and HIV through a systematic search of the literature using PubMed and EMBASE (2004-2006). Original studies that reported sensitivity and specificity data were included. Two reviewers independently extracted data on study characteristics and diagnostic accuracy, and used QUADAS and STARD to evaluate the quality of methods and reporting, respectively. Ninety (38%) of 238 articles met inclusion criteria. All studies had design deficiencies. Study quality indicators that were met in less than 25% of the studies included adequate description of withdrawals (6%) and reference test execution (10%), absence of index test review bias (19%) and reference test review bias (24%), and report of uninterpretable results (22%). In terms of quality of reporting, 9 STARD indicators were reported in less than 25% of the studies: methods for calculation and estimates of reproducibility (0%), adverse effects of the diagnostic tests (1%), estimates of diagnostic accuracy between subgroups (10%), distribution of severity of disease/other diagnoses (11%), number of eligible patients who did not participate in the study (14%), blinding of the test readers (16%), and description of the team executing the test and management of indeterminate/outlier results (both 17%). The use of STARD was not explicitly mentioned in any study. Only 22% of 46 journals that published the studies included in this review required authors to use STARD. Recently published diagnostic accuracy studies on commercial tests for TB, malaria and HIV have moderate to low quality and are poorly reported. The more frequent use of tools such as QUADAS and STARD may be necessary to improve the methodological and reporting quality of future diagnostic accuracy studies in infectious diseases.

Quality and Reporting of Diagnostic Accuracy Studies in TB, HIV and Malaria: Evaluation Using QUADAS and STARD Standards

PubMed Central

Fontela, Patricia Scolari; Pant Pai, Nitika; Schiller, Ian; Dendukuri, Nandini; Ramsay, Andrew; Pai, Madhukar

2009-01-01

Background Poor methodological quality and reporting are known concerns with diagnostic accuracy studies. In 2003, the QUADAS tool and the STARD standards were published for evaluating the quality and improving the reporting of diagnostic studies, respectively. However, it is unclear whether these tools have been applied to diagnostic studies of infectious diseases. We performed a systematic review on the methodological and reporting quality of diagnostic studies in TB, malaria and HIV. Methods We identified diagnostic accuracy studies of commercial tests for TB, malaria and HIV through a systematic search of the literature using PubMed and EMBASE (2004–2006). Original studies that reported sensitivity and specificity data were included. Two reviewers independently extracted data on study characteristics and diagnostic accuracy, and used QUADAS and STARD to evaluate the quality of methods and reporting, respectively. Findings Ninety (38%) of 238 articles met inclusion criteria. All studies had design deficiencies. Study quality indicators that were met in less than 25% of the studies included adequate description of withdrawals (6%) and reference test execution (10%), absence of index test review bias (19%) and reference test review bias (24%), and report of uninterpretable results (22%). In terms of quality of reporting, 9 STARD indicators were reported in less than 25% of the studies: methods for calculation and estimates of reproducibility (0%), adverse effects of the diagnostic tests (1%), estimates of diagnostic accuracy between subgroups (10%), distribution of severity of disease/other diagnoses (11%), number of eligible patients who did not participate in the study (14%), blinding of the test readers (16%), and description of the team executing the test and management of indeterminate/outlier results (both 17%). The use of STARD was not explicitly mentioned in any study. Only 22% of 46 journals that published the studies included in this review required authors to use STARD. Conclusion Recently published diagnostic accuracy studies on commercial tests for TB, malaria and HIV have moderate to low quality and are poorly reported. The more frequent use of tools such as QUADAS and STARD may be necessary to improve the methodological and reporting quality of future diagnostic accuracy studies in infectious diseases. PMID:19915664

Process diagnostics and monitoring using the multipole resonance probe in an inhomogeneous plasma for ion-assisted deposition of optical coatings

NASA Astrophysics Data System (ADS)

Styrnoll, T.; Harhausen, J.; Lapke, M.; Storch, R.; Brinkmann, R. P.; Foest, R.; Ohl, A.; Awakowicz, P.

2013-08-01

The application of a multipole resonance probe (MRP) for diagnostic and monitoring purposes in a plasma ion-assisted deposition (PIAD) process is reported. Recently, the MRP was proposed as an economical and industry compatible plasma diagnostic device (Lapke et al 2011 Plasma Sources Sci. Technol. 20 042001). The major advantages of the MRP are its robustness against dielectric coating and its high sensitivity to measure the electron density. The PIAD process investigated is driven by the advanced plasma source (APS), which generates an ion beam in the deposition chamber for the production of high performance optical coatings. With a background neutral pressure of p0 ˜ 20 mPa the plasma expands from the source region into the recipient, leading to an inhomogeneous spatial distribution. Electron density and electron temperature vary over the distance from substrate (ne ˜ 109 cm-3 and Te,eff ˜ 2 eV) to the APS (ne ≳ 1012 cm-3 and Te,eff ˜ 20 eV) (Harhausen et al 2012 Plasma Sources Sci. Technol. 21 035012). This huge variation of the plasma parameters represents a big challenge for plasma diagnostics to operate precisely for all plasma conditions. The results obtained by the MRP are compared to those from a Langmuir probe chosen as reference diagnostics. It is demonstrated that the MRP is suited for the characterization of the PIAD plasma as well as for electron density monitoring. The latter aspect offers the possibility to develop new control schemes for complex industrial plasma environments.

CORRTEX Diagnostic Deployment for the SPE-III experiment, 24 July 2012: Fielding Report and Preliminary Data Analysis

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

Sandoval, Thomas D.; Schultz-Fellenz, Emily S.

2012-08-29

The Continuous Reflectometry for Radius vs Time Experiments (CORRTEX) diagnostic system was deployed for the third explosives test in the Source Physics Experiment (SPE) sequence to monitor and verify several conditions of the experiment including the detonation velocity of the explosive package and functioning of explosive initiators. Six distance-marked coaxial cables were installed on the SPE-III explosives canister, and key locations documented through along-cable length measurements and photography. CORRTEX uses electrical-pulse time-domain reflectometry to continuously record the two-way transit time (TWTT) of the cables. As the shock front of the detonation advances, the coaxial cable is shorted or destroyed, andmore » the resulting TWTT also decreases. Interpretation of these changes as a function of TWTT can be converted to positional measurements using known parameters of the cables.« less

CompareTests-R package

Cancer.gov

CompareTests is an R package to estimate agreement and diagnostic accuracy statistics for two diagnostic tests when one is conducted on only a subsample of specimens. A standard test is observed on all specimens.

Economic challenges associated with tuberculosis diagnostic development

PubMed Central

Hanrahan, Colleen F.; Shah, Maunank

2015-01-01

Tuberculosis remains a global health crisis in part due to underdiagnosis. Technological innovations are needed to improve diagnostic test accuracy and reduce the reliance on expensive laboratory infrastructure. However, there are significant economic challenges impeding the development and implementation of new diagnostics. The aim of this piece is to examine the current state of TB diagnostics, outline the unmet needs for new tests, and detail the economic challenges associated with development of new tests from the perspective of developers, policy makers and implementers. PMID:24766367

Economic challenges associated with tuberculosis diagnostic development.

PubMed

Hanrahan, Colleen F; Shah, Maunank

2014-08-01

Tuberculosis remains a global health crisis in part due to underdiagnosis. Technological innovations are needed to improve diagnostic test accuracy and reduce the reliance on expensive laboratory infrastructure. However, there are significant economic challenges impeding the development and implementation of new diagnostics. The aim of this piece is to examine the current state of TB diagnostics, outline the unmet needs for new tests, and detail the economic challenges associated with development of new tests from the perspective of developers, policy makers and implementers.

Accuracy of LightCycler(R) SeptiFast for the detection and identification of pathogens in the blood of patients with suspected sepsis: a systematic review protocol.

PubMed

Dark, Paul; Wilson, Claire; Blackwood, Bronagh; McAuley, Danny F; Perkins, Gavin D; McMullan, Ronan; Gates, Simon; Warhurst, Geoffrey

2012-01-01

Background There is growing interest in the potential utility of molecular diagnostics in improving the detection of life-threatening infection (sepsis). LightCycler® SeptiFast is a multipathogen probe-based real-time PCR system targeting DNA sequences of bacteria and fungi present in blood samples within a few hours. We report here the protocol of the first systematic review of published clinical diagnostic accuracy studies of this technology when compared with blood culture in the setting of suspected sepsis. Methods/design Data sources: the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects (DARE), the Health Technology Assessment Database (HTA), the NHS Economic Evaluation Database (NHSEED), The Cochrane Library, MEDLINE, EMBASE, ISI Web of Science, BIOSIS Previews, MEDION and the Aggressive Research Intelligence Facility Database (ARIF). diagnostic accuracy studies that compare the real-time PCR technology with standard culture results performed on a patient's blood sample during the management of sepsis. three reviewers, working independently, will determine the level of evidence, methodological quality and a standard data set relating to demographics and diagnostic accuracy metrics for each study. Statistical analysis/data synthesis: heterogeneity of studies will be investigated using a coupled forest plot of sensitivity and specificity and a scatter plot in Receiver Operator Characteristic (ROC) space. Bivariate model method will be used to estimate summary sensitivity and specificity. The authors will investigate reporting biases using funnel plots based on effective sample size and regression tests of asymmetry. Subgroup analyses are planned for adults, children and infection setting (hospital vs community) if sufficient data are uncovered. Dissemination Recommendations will be made to the Department of Health (as part of an open-access HTA report) as to whether the real-time PCR technology has sufficient clinical diagnostic accuracy potential to move forward to efficacy testing during the provision of routine clinical care. Registration PROSPERO-NIHR Prospective Register of Systematic Reviews (CRD42011001289).

Lead poisoning in dogs: occurrence, source, clinical pathology, and electroencephalography

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

Zook, B.C.; Carpenter, J.L.; Roberts, R.M.

1972-05-01

Accidental lead poisoning was diagnosed and studied in 236 dogs. The disease incidence increased annually after 1963 and was more common in Poodles and dogs less than 1 year old. The incidence was greatest in summer and early fall and was more common in dogs which dwelt in slum areas than was expected. Lead-based paints were the most frequent source of poisoning. Results of hematologic and urinary determinations supported those of previous studies. The diagnostic importance of nucleated and stippled red blood cells (RBC) in peripheral blood films was emphasized, and urine sediments frequently contained casts with few inflammatory cells.more » In addition, reticulocyte counts were usually increased and sedimentation rates and Coomb's test results were normal. Results of bone marrow studies indicated hyperplasia of, and partial maturation defect in, the erythrocytic series of most dogs. Determinations of various clinical chemistry tests and cerebrospinal fluid analysis were usually normal. Electroencephalographic changes consisted of irregular, generalized slow-wave activity of increased amplitude. 20 references, 5 figures, 12 tables.« less

[Companion diagnostics in the era of personalized medicine--chairmen's introductory remarks].

PubMed

Fukutsuka, Katsuhiro; Takubo, Takayuki

2014-04-01

Personalized medicine is a medical model that proposes the customization of treatment for individual patients. In this model, diagnostic tests are essential for selecting safer and more efficacious treatments. The term "companion diagnostics" has been used to describe these tests, whereby molecular assays that measure the levels of proteins or specific gene mutations are used to provide a specific therapy for an individual by stratifying the disease status, selecting the proper medication, and tailoring dosages. Examples of companion diagnostics in the field of cancer medicine for molecular targeted therapy include tests for the ALK-fusion gene in non-small cell lung cancer and expression of CCR4 in adult T-cell leukemia. For breast cancer, the expression of HER2 protein is evaluated by immunohistochemistry (IHC), and gene amplification of HER2 is tested by fluorescence in situ hybridization (FISH); both tests consist of pre-analysis, analysis, and post-analysis processes that require quality control to ensure the reliability of the results. This symposium includes: 1) future aspects of companion diagnostics addressing many of the problems that must be overcome, 2) companion diagnostics using FISH focusing on HER2 amplification and ALK alteration, 3) newly developed diagnostic tests using tumor specimens and cell-free DNA in serum, and 4) CCR4 expression detected by IHC and flow cytometry.

Evaluating online direct-to-consumer marketing of genetic tests: informed choices or buyers beware?

PubMed

Geransar, Rose; Einsiedel, Edna

2008-03-01

Commercialization of genetic technologies is expanding the horizons for the marketing and sales of genetic tests direct-to-consumers (DTCs). This study assesses the information provision and access requirements that are in place for genetic tests that are being advertised DTC over the Internet. Sets of key words specific to DTC genetic testing were entered into popular Internet search engines to generate a list of 24 companies engaging in DTC advertising. Company requirements for physician mediation, genetic counseling arrangements, and information provision were coded to develop categories for quantitative analysis within each variable. Results showed that companies offering risk assessment and diagnostic testing were most likely to require that testing be mediated by a clinician, and to recommend physician-arranged counseling. Companies offering enhancement testing were less likely to require physician mediation of services and more likely to provide long-distance genetic counseling. DTC advertisements often provided information on disease etiology; this was most common in the case of multifactorial diseases. The majority of companies cited outside sources to support the validity of claims about clinical utility of the tests being advertised; companies offering risk assessment tests most frequently cited all information sources. DTC advertising for genetic tests that lack independent professional oversight raises troubling questions about appropriate use and interpretation of these tests by consumers and carries implications for the standards of patient care. These implications are discussed in the context of a public healthcare system.

Evaluation of canine adverse food reactions by patch testing with single proteins, single carbohydrates and commercial foods.

PubMed

Johansen, Cornelia; Mariani, Claire; Mueller, Ralf S

2017-10-01

Adverse food reaction (AFR) is an important differential diagnosis for the pruritic dog. It is usually diagnosed by feeding an elimination diet with a novel protein and carbohydrate source for eight weeks followed by subsequent food provocation. A previous study demonstrated that patch testing dogs with foods had a high sensitivity and negative predictability for selection of elimination diet ingredients. The aim of this study was to investigate patch testing with proteins, carbohydrates and dry commercial dog food in dogs to determine whether there was value in patch testing to aid the diagnosis of canine adverse food reaction. Twenty five privately owned dogs, with confirmed AFR, underwent provocation trials with selected food antigens and patch testing. For proteins, carbohydrates and dry dog food the sensitivity of patch testing was 100%, 70% and 22.2%, respectively; the negative predictive values of patch testing were 100%, 79% and 72%. The positive predictive values of patch testing for proteins and carbohydrates were 75% and 74%, respectively. This study confirmed that patch testing may be useful for the selection of a suitable protein source for an elimination diet in dogs with suspected AFR, but not as a diagnostic tool for canine AFR. Results for proteins are more reliable than for carbohydrates and the majority of positive patch test reactions were observed with raw protein. Patch testing with commercial dog food does not seem to be useful. © 2017 ESVD and ACVD.

Xanthos

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

2017-05-30

Xanthos is a Python package designed to quantify and analyze global water availability in history and in future at 0.5° × 0.5° spatial resolution and a monthly time step under a changing climate. Its performance was also tested through real applications. It is open-source, extendable and convenient to researchers who work on long-term climate data for studies of global water supply, and Global Change Assessment Model (GCAM). This package integrates inherent global gridded data maps, I/O modules, Water-Balance Model modules and diagnostics modules by user-defined configuration.

WHO Study on the reliability and validity of the alcohol and drug use disorder instruments: overview of methods and results.

PubMed

Ustün, B; Compton, W; Mager, D; Babor, T; Baiyewu, O; Chatterji, S; Cottler, L; Göğüş, A; Mavreas, V; Peters, L; Pull, C; Saunders, J; Smeets, R; Stipec, M R; Vrasti, R; Hasin, D; Room, R; Van den Brink, W; Regier, D; Blaine, J; Grant, B F; Sartorius, N

1997-09-25

The WHO Study on the reliability and validity of the alcohol and drug use disorder instruments in an international study which has taken place in centres in ten countries, aiming to test the reliability and validity of three diagnostic instruments for alcohol and drug use disorders: the Composite International Diagnostic Interview (CIDI), the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) and a special version of the Alcohol Use Disorder and Associated Disabilities Interview schedule-alcohol/drug-revised (AUDADIS-ADR). The purpose of the reliability and validity (R&V) study is to further develop the alcohol and drug sections of these instruments so that a range of substance-related diagnoses can be made in a systematic, consistent, and reliable way. The study focuses on new criteria proposed in the tenth revision of the International Classification of Diseases (ICD-10) and the fourth revision of the diagnostic and statistical manual of mental disorders (DSM-IV) for dependence, harmful use and abuse categories for alcohol and psychoactive substance use disorders. A systematic study including a scientifically rigorous measure of reliability (i.e. 1 week test-retest reliability) and validity (i.e. comparison between clinical and non-clinical measures) has been undertaken. Results have yielded useful information on reliability and validity of these instruments at diagnosis, criteria and question level. Overall the diagnostic concordance coefficients (kappa, kappa) were very good for dependence disorders (0.7-0.9), but were somewhat lower for the abuse and harmful use categories. The comparisons among instruments and independent clinical evaluations and debriefing interviews gave important information about possible sources of unreliability, and provided useful clues on the applicability and consistency of nosological concepts across cultures.

Pitfalls in genetic testing: a case of a SNP in primer-annealing region leading to allele dropout in BRCA1.

PubMed

Silva, Felipe Carneiro; Torrezan, Giovana Tardin; Brianese, Rafael Canfield; Stabellini, Raquel; Carraro, Dirce Maria

2017-07-01

Hereditary breast and ovarian cancer is characterized by mutations in BRCA1 or BRCA2 genes and PCR-based screening techniques, such as capillary sequencing and next-generation sequencing (NGS), are considered gold standard methods for detection of pathogenic mutations in these genes. Single-nucleotide polymorphisms (SNPs) constitute a vast source of variation in the human genome and represent a risk for misdiagnosis in genetic testing, since the presence of a SNP in primer-annealing sites may cause false negative results due to allele dropout. However, few reports are available and the frequency of this phenomenon in diagnostic assays remains unknown. In this article, we investigated the causes of a false negative capillary sequencing result in BRCA1 involving a mother-daughter dyad. Using several molecular strategies, including different DNA polymerases, primer redesign, allele-specific PCR and NGS, we established that the initial misdiagnosis was caused by a SNP located in the primer-annealing region, leading to allele dropout of the mutated allele. Assuming that this problem can also occur in any PCR-based method that are widely used in diagnostic settings, the clinical report presented here draws attention for one of the limitations of genetic testing in general, for which medical and laboratory communities need to be aware.

Interpretation of diagnostic data: 5. How to do it with simple maths.

PubMed

1983-11-01

The use of simple maths with the likelihood ratio strategy fits in nicely with our clinical views. By making the most out of the entire range of diagnostic test results (i.e., several levels, each with its own likelihood ratio, rather than a single cut-off point and a single ratio) and by permitting us to keep track of the likelihood that a patient has the target disorder at each point along the diagnostic sequence, this strategy allows us to place patients at an extremely high or an extremely low likelihood of disease. Thus, the numbers of patients with ultimately false-positive results (who suffer the slings of labelling and the arrows of needless therapy) and of those with ultimately false-negative results (who therefore miss their chance for diagnosis and, possibly, efficacious therapy) will be dramatically reduced. The following guidelines will be useful in interpreting signs, symptoms and laboratory tests with the likelihood ratio strategy: Seek out, and demand from the clinical or laboratory experts who ought to know, the likelihood ratios for key symptoms and signs, and several levels (rather than just the positive and negative results) of diagnostic test results. Identify, when feasible, the logical sequence of diagnostic tests. Estimate the pretest probability of disease for the patient, and, using either the nomogram or the conversion formulas, apply the likelihood ratio that corresponds to the first diagnostic test result. While remembering that the resulting post-test probability or odds from the first test becomes the pretest probability or odds for the next diagnostic test, repeat the process for all the pertinent symptoms, signs and laboratory studies that pertain to the target disorder. However, these combinations may not be independent, and convergent diagnostic tests, if treated as independent, will combine to overestimate the final post-test probability of disease. You are now far more sophisticated in interpreting diagnostic tests than most of your teachers. In the last part of our series we will show you some rather complex strategies that combine diagnosis and therapy, quantify our as yet nonquantified ideas about use, and require the use of at least a hand calculator.

Interpretation of diagnostic data: 5. How to do it with simple maths.

PubMed Central

1983-01-01

The use of simple maths with the likelihood ratio strategy fits in nicely with our clinical views. By making the most out of the entire range of diagnostic test results (i.e., several levels, each with its own likelihood ratio, rather than a single cut-off point and a single ratio) and by permitting us to keep track of the likelihood that a patient has the target disorder at each point along the diagnostic sequence, this strategy allows us to place patients at an extremely high or an extremely low likelihood of disease. Thus, the numbers of patients with ultimately false-positive results (who suffer the slings of labelling and the arrows of needless therapy) and of those with ultimately false-negative results (who therefore miss their chance for diagnosis and, possibly, efficacious therapy) will be dramatically reduced. The following guidelines will be useful in interpreting signs, symptoms and laboratory tests with the likelihood ratio strategy: Seek out, and demand from the clinical or laboratory experts who ought to know, the likelihood ratios for key symptoms and signs, and several levels (rather than just the positive and negative results) of diagnostic test results. Identify, when feasible, the logical sequence of diagnostic tests. Estimate the pretest probability of disease for the patient, and, using either the nomogram or the conversion formulas, apply the likelihood ratio that corresponds to the first diagnostic test result. While remembering that the resulting post-test probability or odds from the first test becomes the pretest probability or odds for the next diagnostic test, repeat the process for all the pertinent symptoms, signs and laboratory studies that pertain to the target disorder. However, these combinations may not be independent, and convergent diagnostic tests, if treated as independent, will combine to overestimate the final post-test probability of disease. You are now far more sophisticated in interpreting diagnostic tests than most of your teachers. In the last part of our series we will show you some rather complex strategies that combine diagnosis and therapy, quantify our as yet nonquantified ideas about use, and require the use of at least a hand calculator. PMID:6671182

A systematic review of the diagnostic performance of orthopedic physical examination tests of the hip

PubMed Central

2013-01-01

Background Previous reviews of the diagnostic performances of physical tests of the hip in orthopedics have drawn limited conclusions because of the low to moderate quality of primary studies published in the literature. This systematic review aims to build on these reviews by assessing a broad range of hip pathologies, and employing a more selective approach to the inclusion of studies in order to accurately gauge diagnostic performance for the purposes of making recommendations for clinical practice and future research. It specifically identifies tests which demonstrate strong and moderate diagnostic performance. Methods A systematic search of Medline, Embase, Embase Classic and CINAHL was conducted to identify studies of hip tests. Our selection criteria included an analysis of internal and external validity. We reported diagnostic performance in terms of sensitivity, specificity, predictive values and likelihood ratios. Likelihood ratios were used to identify tests with strong and moderate diagnostic utility. Results Only a small proportion of tests reported in the literature have been assessed in methodologically valid primary studies. 16 studies were included in our review, producing 56 independent test-pathology combinations. Two tests demonstrated strong clinical utility, the patellar-pubic percussion test for excluding radiologically occult hip fractures (negative LR 0.05, 95% Confidence Interval [CI] 0.03-0.08) and the hip abduction sign for diagnosing sarcoglycanopathies in patients with known muscular dystrophies (positive LR 34.29, 95% CI 10.97-122.30). Fifteen tests demonstrated moderate diagnostic utility for diagnosing and/or excluding hip fractures, symptomatic osteoarthritis and loosening of components post-total hip arthroplasty. Conclusions We have identified a number of tests demonstrating strong and moderate diagnostic performance. These findings must be viewed with caution as there are concerns over the methodological quality of the primary studies from which we have extracted our data. Future studies should recruit larger, representative populations and allow for the construction of complete 2×2 contingency tables. PMID:23987589

A systematic review of the diagnostic performance of orthopedic physical examination tests of the hip.

PubMed

Rahman, Labib Ataur; Adie, Sam; Naylor, Justine Maree; Mittal, Rajat; So, Sarah; Harris, Ian Andrew

2013-08-30

Previous reviews of the diagnostic performances of physical tests of the hip in orthopedics have drawn limited conclusions because of the low to moderate quality of primary studies published in the literature. This systematic review aims to build on these reviews by assessing a broad range of hip pathologies, and employing a more selective approach to the inclusion of studies in order to accurately gauge diagnostic performance for the purposes of making recommendations for clinical practice and future research. It specifically identifies tests which demonstrate strong and moderate diagnostic performance. A systematic search of Medline, Embase, Embase Classic and CINAHL was conducted to identify studies of hip tests. Our selection criteria included an analysis of internal and external validity. We reported diagnostic performance in terms of sensitivity, specificity, predictive values and likelihood ratios. Likelihood ratios were used to identify tests with strong and moderate diagnostic utility. Only a small proportion of tests reported in the literature have been assessed in methodologically valid primary studies. 16 studies were included in our review, producing 56 independent test-pathology combinations. Two tests demonstrated strong clinical utility, the patellar-pubic percussion test for excluding radiologically occult hip fractures (negative LR 0.05, 95% Confidence Interval [CI] 0.03-0.08) and the hip abduction sign for diagnosing sarcoglycanopathies in patients with known muscular dystrophies (positive LR 34.29, 95% CI 10.97-122.30). Fifteen tests demonstrated moderate diagnostic utility for diagnosing and/or excluding hip fractures, symptomatic osteoarthritis and loosening of components post-total hip arthroplasty. We have identified a number of tests demonstrating strong and moderate diagnostic performance. These findings must be viewed with caution as there are concerns over the methodological quality of the primary studies from which we have extracted our data. Future studies should recruit larger, representative populations and allow for the construction of complete 2×2 contingency tables.

Systematic Review of the Diagnostic Accuracy and Therapeutic Effectiveness of Sacroiliac Joint Interventions.

PubMed

Simopoulos, Thomas T; Manchikanti, Laxmaiah; Gupta, Sanjeeva; Aydin, Steve M; Kim, Chong Hwan; Solanki, Daneshvari; Nampiaparampil, Devi E; Singh, Vijay; Staats, Peter S; Hirsch, Joshua A

2015-01-01

The sacroiliac joint is well known as a cause of low back and lower extremity pain. Prevalence estimates are 10% to 25% in patients with persistent axial low back pain without disc herniation, discogenic pain, or radiculitis based on multiple diagnostic studies and systematic reviews. However, at present there are no definitive management options for treating sacroiliac joint pain. To evaluate the diagnostic accuracy and therapeutic effectiveness of sacroiliac joint interventions. A systematic review of the diagnostic accuracy and therapeutic effectiveness of sacroiliac joint interventions. The available literature on diagnostic and therapeutic sacroiliac joint interventions was reviewed. The quality assessment criteria utilized were the Quality Appraisal of Reliability Studies (QAREL) checklist for diagnostic accuracy studies, Cochrane review criteria to assess sources of risk of bias, and Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB) criteria for randomized therapeutic trials and Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment for Nonrandomized Studies (IPM-QRBNR) for observational therapeutic assessments. The level of evidence was based on a best evidence synthesis with modified grading of qualitative evidence from Level I to Level V. Data sources included relevant literature published from 1966 through March 2015 that were identified through searches of PubMed and EMBASE, manual searches of the bibliographies of known primary and review articles, and all other sources. For the diagnostic accuracy assessment, and for the therapeutic modalities, the primary outcome measure of pain relief and improvement in functional status were utilized. A total of 11 diagnostic accuracy studies and 14 therapeutic studies were included. The evidence for diagnostic accuracy is Level II for dual diagnostic blocks with at least 70% pain relief as the criterion standard and Level III evidence for single diagnostic blocks with at least 75% pain relief as the criterion standard. The evidence for cooled radiofrequency neurotomy in managing sacroiliac joint pain is Level II to III. The evidence for conventional radiofrequency neurotomy, intraarticular steroid injections, and periarticular injections with steroids or botulinum toxin is limited: Level III or IV. The limitations of this systematic review include inconsistencies in diagnostic accuracy studies with a paucity of high quality, replicative, and consistent literature. The limitations for therapeutic interventions include variations in technique, variable diagnostic standards for inclusion criteria, and variable results. The evidence for the accuracy of diagnostic and therapeutic effectiveness of sacroiliac joint interventions varied from Level II to Level IV.

Network meta-analysis of diagnostic test accuracy studies identifies and ranks the optimal diagnostic tests and thresholds for health care policy and decision-making.

PubMed

Owen, Rhiannon K; Cooper, Nicola J; Quinn, Terence J; Lees, Rosalind; Sutton, Alex J

2018-07-01

Network meta-analyses (NMA) have extensively been used to compare the effectiveness of multiple interventions for health care policy and decision-making. However, methods for evaluating the performance of multiple diagnostic tests are less established. In a decision-making context, we are often interested in comparing and ranking the performance of multiple diagnostic tests, at varying levels of test thresholds, in one simultaneous analysis. Motivated by an example of cognitive impairment diagnosis following stroke, we synthesized data from 13 studies assessing the efficiency of two diagnostic tests: Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA), at two test thresholds: MMSE <25/30 and <27/30, and MoCA <22/30 and <26/30. Using Markov chain Monte Carlo (MCMC) methods, we fitted a bivariate network meta-analysis model incorporating constraints on increasing test threshold, and accounting for the correlations between multiple test accuracy measures from the same study. We developed and successfully fitted a model comparing multiple tests/threshold combinations while imposing threshold constraints. Using this model, we found that MoCA at threshold <26/30 appeared to have the best true positive rate, whereas MMSE at threshold <25/30 appeared to have the best true negative rate. The combined analysis of multiple tests at multiple thresholds allowed for more rigorous comparisons between competing diagnostics tests for decision making. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Overdiagnosis across medical disciplines: a scoping review.

PubMed

Jenniskens, Kevin; de Groot, Joris A H; Reitsma, Johannes B; Moons, Karel G M; Hooft, Lotty; Naaktgeboren, Christiana A

2017-12-27

To provide insight into how and in what clinical fields overdiagnosis is studied and give directions for further applied and methodological research. Scoping review. Medline up to August 2017. All English studies on humans, in which overdiagnosis was discussed as a dominant theme. Studies were assessed on clinical field, study aim (ie, methodological or non-methodological), article type (eg, primary study, review), the type and role of diagnostic test(s) studied and the context in which these studies discussed overdiagnosis. From 4896 studies, 1851 were included for analysis. Half of all studies on overdiagnosis were performed in the field of oncology (50%). Other prevalent clinical fields included mental disorders, infectious diseases and cardiovascular diseases accounting for 9%, 8% and 6% of studies, respectively. Overdiagnosis was addressed from a methodological perspective in 20% of studies. Primary studies were the most common article type (58%). The type of diagnostic tests most commonly studied were imaging tests (32%), although these were predominantly seen in oncology and cardiovascular disease (84%). Diagnostic tests were studied in a screening setting in 43% of all studies, but as high as 75% of all oncological studies. The context in which studies addressed overdiagnosis related most frequently to its estimation, accounting for 53%. Methodology on overdiagnosis estimation and definition provided a source for extensive discussion. Other contexts of discussion included definition of disease, overdiagnosis communication, trends in increasing disease prevalence, drivers and consequences of overdiagnosis, incidental findings and genomics. Overdiagnosis is discussed across virtually all clinical fields and in different contexts. The variability in characteristics between studies and lack of consensus on overdiagnosis definition indicate the need for a uniform typology to improve coherence and comparability of studies on overdiagnosis. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Assessing Diagnostic Tests I: You Can't Be Too Sensitive.

PubMed

Jupiter, Daniel C

2015-01-01

Clinicians and patients are always interested in less invasive, cheaper, and faster diagnostic tests. When introducing such a test, physicians must ensure that it is reliable in its diagnoses and does not commit errors. In this article, I discuss several ways that new tests are compared against gold standard diagnostics. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

SSME HPOTP post-test diagnostic system enhancement project

NASA Technical Reports Server (NTRS)

Bickmore, Timothy W.

1995-01-01

An assessment of engine and component health is routinely made after each test or flight firing of a space shuttle main engine (SSME). Currently, this health assessment is done by teams of engineers who manually review sensor data, performance data, and engine and component operating histories. Based on review of information from these various sources, an evaluation is made as to the health of each component of the SSME and the preparedness of the engine for another test or flight. The objective of this project is to further develop a computer program which automates the analysis of test data from the SSME high-pressure oxidizer turbopump (HPOTP) in order to detect and diagnose anomalies. This program fits into a larger system, the SSME Post-Test Diagnostic System (PTDS), which will eventually be extended to assess the health and status of most SSME components on the basis of test data analysis. The HPOTP module is an expert system, which uses 'rules-of-thumb' obtained from interviews with experts from NASA Marshall Space Flight Center (MSFC) to detect and diagnose anomalies. Analyses of the raw test data are first performed using pattern recognition techniques which result in features such as spikes, shifts, peaks, and drifts being detected and written to a database. The HPOTP module then looks for combination of these features which are indicative of known anomalies, using the rules gathered from the turbomachinery experts. Results of this analysis are then displayed via a graphical user interface which provides ranked lists of anomalies and observations by engine component, along with supporting data plots for each.

Gearbox vibration diagnostic analyzer

NASA Technical Reports Server (NTRS)

1992-01-01

This report describes the Gearbox Vibration Diagnostic Analyzer installed in the NASA Lewis Research Center's 500 HP Helicopter Transmission Test Stand to monitor gearbox testing. The vibration of the gearbox is analyzed using diagnostic algorithms to calculate a parameter indicating damaged components.

Diagnostics of underwater electrical wire explosion through a time- and space-resolved hard x-ray source

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

Sheftman, D.; Shafer, D.; Efimov, S.

2012-10-15

A time- and space-resolved hard x-ray source was developed as a diagnostic tool for imaging underwater exploding wires. A {approx}4 ns width pulse of hard x-rays with energies of up to 100 keV was obtained from the discharge in a vacuum diode consisting of point-shaped tungsten electrodes. To improve contrast and image quality, an external pulsed magnetic field produced by Helmholtz coils was used. High resolution x-ray images of an underwater exploding wire were obtained using a sensitive x-ray CCD detector, and were compared to optical fast framing images. Future developments and application of this diagnostic technique are discussed.

Diagnostics of underwater electrical wire explosion through a time- and space-resolved hard x-ray source.

PubMed

Sheftman, D; Shafer, D; Efimov, S; Gruzinsky, K; Gleizer, S; Krasik, Ya E

2012-10-01

A time- and space-resolved hard x-ray source was developed as a diagnostic tool for imaging underwater exploding wires. A ~4 ns width pulse of hard x-rays with energies of up to 100 keV was obtained from the discharge in a vacuum diode consisting of point-shaped tungsten electrodes. To improve contrast and image quality, an external pulsed magnetic field produced by Helmholtz coils was used. High resolution x-ray images of an underwater exploding wire were obtained using a sensitive x-ray CCD detector, and were compared to optical fast framing images. Future developments and application of this diagnostic technique are discussed.

Effects of Training on the Test of Diagnostic Skills. Publication No. 30.

ERIC Educational Resources Information Center

Haley, John V.

This report summarizes research performed on the Test of Diagnostic Skills, used to evaluate the clinical diagnostic skills of medical students. Forms of the test were administered to groups at different levels of medical experience to ascertain the effect of training on performance. A cross-sectional study was conducted with approximately 90…

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

30 CFR 250.523 - How long do I keep records of casing pressure and diagnostic tests?

Code of Federal Regulations, 2010 CFR

2010-07-01

... field office nearest the well for a minimum of 2 years. The last casing diagnostic test for each casing... and diagnostic tests? 250.523 Section 250.523 Mineral Resources MINERALS MANAGEMENT SERVICE... Gas Well-Completion Operations Casing Pressure Management § 250.523 How long do I keep records of...

Understanding the medical and nonmedical value of diagnostic testing.

PubMed

Lee, David W; Neumann, Peter J; Rizzo, John A

2010-01-01

To develop a framework for defining the potential value of diagnostic testing, and discuss its implications for the health-care delivery system. We reviewed the conceptual and empirical literature related to the valuing of diagnostic tests, and used this information to create a framework for characterizing their value. We then made inferences about the impact of this framework on health insurance coverage, health technology assessment, physician-patient relationships, and public health policy. Three dimensions can effectively classify the potential value created by diagnostic tests: 1) medical value (impact on treatment decisions); 2) planning value (affect on patients' ability to make better life decisions); and 3) psychic value (how test information affects patients' sense of self). This comprehensive framework for valuing diagnostics suggests that existing health technology assessments may systematically under- or overvalue diagnostics, leading to potentially incorrect conclusions about cost-effectiveness. Further, failure to account for all value dimensions may lead to distorted payments under a value-based health-care system. The potential value created by medical diagnostics incorporates medical value as well as value associated with well-being and planning. Consideration of all three dimensions has important implications for technology assessment and value-based payment.

Value of physical tests in diagnosing cervical radiculopathy: a systematic review.

PubMed

Thoomes, Erik J; van Geest, Sarita; van der Windt, Danielle A; Falla, Deborah; Verhagen, Arianne P; Koes, Bart W; Thoomes-de Graaf, Marloes; Kuijper, Barbara; Scholten-Peeters, Wendy G M; Vleggeert-Lankamp, Carmen L

2018-01-01

In clinical practice, the diagnosis of cervical radiculopathy is based on information from the patient's history, physical examination, and diagnostic imaging. Various physical tests may be performed, but their diagnostic accuracy is unknown. This study aimed to summarize and update the evidence on diagnostic performance of tests carried out during a physical examination for the diagnosis of cervical radiculopathy. A review of the accuracy of diagnostic tests was carried out. The study sample comprised diagnostic studies comparing results of tests performed during a physical examination in diagnosing cervical radiculopathy with a reference standard of imaging or surgical findings. Sensitivity, specificity, likelihood ratios are presented, together with pooled results for sensitivity and specificity. A literature search up to March 2016 was performed in CENTRAL, PubMed (MEDLINE), Embase, CINAHL, Web of Science, and Google Scholar. The methodological quality of studies was assessed using the QUADAS-2. Five diagnostic accuracy studies were identified. Only Spurling's test was evaluated in more than one study, showing high specificity ranging from 0.89 to 1.00 (95% confidence interval [CI]: 0.59-1.00); sensitivity varied from 0.38 to 0.97 (95% CI: 0.21-0.99). No studies were found that assessed the diagnostic accuracy of widely used neurological tests such as key muscle strength, tendon reflexes, and sensory impairments. There is limited evidence for accuracy of physical examination tests for the diagnosis of cervical radiculopathy. When consistent with patient history, clinicians may use a combination of Spurling's, axial traction, and an Arm Squeeze test to increase the likelihood of a cervical radiculopathy, whereas a combined results of four negative neurodynamics tests and an Arm Squeeze test could be used to rule out the disorder. Copyright © 2017 Elsevier Inc. All rights reserved.

Noncontact techniques for diesel engine diagnostics using exhaust waveform analysis

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

Gore, D.A.; Cooke, G.J.

1987-01-01

RCA Corporation's continuing efforts to develop noncontact test techniques for diesel engines have led to recent advancements in deep engine diagnostics. The U.S. Army Tank-Automotive Command (TACOM) has been working with RCA for the development of new noncontact sensors and test techniques which use these sensors in conjunction with their family of Simplified Test Equipment (STE) to perform vehicle diagnostics. The STE systems are microprocessor-based maintenance tools that assist the Army mechanic in diagnosing malfunctions in both tactical and combat vehicles. The test systems support the mechanic by providing the sophisticated signal processing capabilities necessary for a wide range ofmore » diagnostic testing including exhaust waveform analysis.« less

Metagenomics: The Next Culture-Independent Game Changer

PubMed Central

Forbes, Jessica D.; Knox, Natalie C.; Ronholm, Jennifer; Pagotto, Franco; Reimer, Aleisha

2017-01-01

A trend towards the abandonment of obtaining pure culture isolates in frontline laboratories is at a crossroads with the ability of public health agencies to perform their basic mandate of foodborne disease surveillance and response. The implementation of culture-independent diagnostic tests (CIDTs) including nucleic acid and antigen-based assays for acute gastroenteritis is leaving public health agencies without laboratory evidence to link clinical cases to each other and to food or environmental substances. This limits the efficacy of public health epidemiology and surveillance as well as outbreak detection and investigation. Foodborne outbreaks have the potential to remain undetected or have insufficient evidence to support source attribution and may inadvertently increase the incidence of foodborne diseases. Next-generation sequencing of pure culture isolates in clinical microbiology laboratories has the potential to revolutionize the fields of food safety and public health. Metagenomics and other ‘omics’ disciplines could provide the solution to a cultureless future in clinical microbiology, food safety and public health. Data mining of information obtained from metagenomics assays can be particularly useful for the identification of clinical causative agents or foodborne contamination, detection of AMR and/or virulence factors, in addition to providing high-resolution subtyping data. Thus, metagenomics assays may provide a universal test for clinical diagnostics, foodborne pathogen detection, subtyping and investigation. This information has the potential to reform the field of enteric disease diagnostics and surveillance and also infectious diseases as a whole. The aim of this review will be to present the current state of CIDTs in diagnostic and public health laboratories as they relate to foodborne illness and food safety. Moreover, we will also discuss the diagnostic and subtyping utility and concomitant bias limitations of metagenomics and comparable detection techniques in clinical microbiology, food and public health laboratories. Early advances in the discipline of metagenomics, however, have indicated noteworthy challenges. Through forthcoming improvements in sequencing technology and analytical pipelines among others, we anticipate that within the next decade, detection and characterization of pathogens via metagenomics-based workflows will be implemented in routine usage in diagnostic and public health laboratories. PMID:28725217

42 CFR 419.2 - Basis of payment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... prospective payment system establishes a national payment rate, standardized for geographic wage differences... X-ray tests, diagnostic laboratory tests, and other diagnostic tests; (10) Durable medical equipment...

Malaria rapid diagnostic tests.

PubMed

Wilson, Michael L

2012-06-01

Global efforts to control malaria are more complex than those for other infectious diseases, in part because of vector transmission, the complex clinical presentation of Plasmodium infections, >1 Plasmodium species causing infection, geographic distribution of vectors and infection, and drug resistance. The World Health Organization approach to global malaria control focuses on 2 components: vector control and diagnosis and treatment of clinical malaria. Although microscopy performed on peripheral blood smears remains the most widely used diagnostic test and the standard against which other tests are measured, rapid expansion of diagnostic testing worldwide will require use of other diagnostic approaches. This review will focus on the malaria rapid diagnostic test (MRDT) for detecting malaria parasitemia, both in terms of performance characteristics of MRDTs and how they are used under field conditions. The emphasis will be on the performance and use of MRDTs in regions of endemicity, particularly sub-Saharan Africa, where most malaria-related deaths occur.

False positive malaria rapid diagnostic test in returning traveler with typhoid fever.

PubMed

Meatherall, Bonnie; Preston, Keith; Pillai, Dylan R

2014-07-09

Rapid diagnostic tests play a pivotal role in the early diagnosis of malaria where microscopy or polymerase chain reaction are not immediately available. We report the case of a 39 year old traveler to Canada who presented with fever, headache, and abdominal pain after visiting friends and relatives in India. While in India, the individual was not ill and had no signs or symptoms of malaria. Laboratory testing upon his return to Canada identified a false positive malaria rapid diagnostic (BinaxNOW® malaria) result for P. falciparum with coincident Salmonella Typhi bacteraemia without rheumatoid or autoimmune factors. Rapid diagnostic test false positivity for malaria coincided with the presence or absence of Salmonella Typhi in the blood. Clinicians should be aware that Salmonella Typhi infection may result in a false positive malaria rapid diagnostic test. The mechanism of this cross-reactivity is not clear.

Rapid diagnostic tests compared with malaria microscopy for guiding outpatient treatment of febrile illness in Tanzania: randomised trial.

PubMed

Reyburn, Hugh; Mbakilwa, Hilda; Mwangi, Rose; Mwerinde, Ombeni; Olomi, Raimos; Drakeley, Chris; Whitty, Christopher J M

2007-02-24

To compare rapid diagnostic tests (RDTs) for malaria with routine microscopy in guiding treatment decisions for febrile patients. Randomised trial. Outpatient departments in northeast Tanzania at varying levels of malaria transmission. 2416 patients for whom a malaria test was requested. Staff received training on rapid diagnostic tests; patients sent for malaria tests were randomised to rapid diagnostic test or routine microscopy Proportion of patients with a negative test prescribed an antimalarial drug. Of 7589 outpatient consultations, 2425 (32%) had a malaria test requested. Of 1204 patients randomised to microscopy, 1030 (86%) tested negative for malaria; 523 (51%) of these were treated with an antimalarial drug. Of 1193 patients randomised to rapid diagnostic test, 1005 (84%) tested negative; 540 (54%) of these were treated for malaria (odds ratio 1.13, 95% confidence interval 0.95 to 1.34; P=0.18). Children aged under 5 with negative rapid diagnostic tests were more likely to be prescribed an antimalarial drug than were those with negative slides (P=0.003). Patients with a negative test by any method were more likely to be prescribed an antibiotic (odds ratio 6.42, 4.72 to 8.75; P<0.001). More than 90% of prescriptions for antimalarial drugs in low-moderate transmission settings were for patients for whom a test requested by a clinician was negative for malaria. Although many cases of malaria are missed outside the formal sector, within it malaria is massively over-diagnosed. This threatens the sustainability of deployment of artemisinin combination treatment, and treatable bacterial diseases are likely to be missed. Use of rapid diagnostic tests, with basic training for clinical staff, did not in itself lead to any reduction in over-treatment for malaria. Interventions to improve clinicians' management of febrile illness are essential but will not be easy. Clinical trials NCT00146796 [ClinicalTrials.gov].

Picosecond x-ray diagnostics for third and fourth generation synchrotron sources

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

DeCamp, Matthew

2016-03-30

In the DOE-EPSCoR State/National Laboratory partnership grant ``Picosecond x-ray diagnostics for third and fourth generation synchrotron sources'' Dr. DeCamp set forth a partnership between the University of Delaware and Argonne National Laboratory. This proposal aimed to design and implement a series of experiments utilizing, or improving upon, existing time-domain hard x-ray spectroscopies at a third generation synchrotron source. Specifically, the PI put forth three experimental projects to be explored in the grant cycle: 1) implementing a picosecond ``x-ray Bragg switch'' using a laser excited nano-structured metallic film, 2) designing a robust x-ray optical delay stage for x-ray pump-probe studies atmore » a hard x-ray synchrotron source, and 3) building/installing a laser based x-ray source at the Advanced Photon Source for two-color x-ray pump-probe studies.« less

How do you get the Rose Bengal Test at the point-of-care to diagnose brucellosis in Africa? The importance of a systems approach.

PubMed

Ducrotoy, Marie J; Bardosh, Kevin L

2017-01-01

Brucellosis is a major neglected zoonotic disease, whose burden both in animals and humans is severely under-reported. Diagnosis in humans identifies cases in order to treat the disease at the individual level. In animals diagnosis is implemented at the population level in the context of appropriate control or eradication strategies. Molecular and bacteriological diagnosis are rarely undertaken in sub-Saharan Africa, at least outside research projects, due to cost, skills and laboratory infrastructure issues. The brucellosis toolbox contains a wide range of serological tests, but the perfect test for use in animals and humans respectively does not exist. Drug and diagnostic discovery for the neglected zoonoses are notoriously poor, and there is limited investment interest in developing new tools for brucellosis diagnosis. But are current tools being used to their full capacity? The rose Bengal test (RBT) stands out as an efficient, practical and very cheap test adapted for use in the resource-poor context. In this paper, we argue that a social science or system's approach to explore the practicality of improving diagnostic capacity at the point-of care in high-risk brucellosis areas of rural Africa may be a step towards solving the issue of under-diagnosis, but this must go hand-in-hand with implementation of control measures at source in the animal reservoir and capacity to treat human cases. Copyright © 2016 Elsevier B.V. All rights reserved.

A Colorimetric Enzyme-Linked Immunosorbent Assay (ELISA) Detection Platform for a Point-of-Care Dengue Detection System on a Lab-on-Compact-Disc

PubMed Central

Thiha, Aung; Ibrahim, Fatimah

2015-01-01

The enzyme-linked Immunosorbent Assay (ELISA) is the gold standard clinical diagnostic tool for the detection and quantification of protein biomarkers. However, conventional ELISA tests have drawbacks in their requirement of time, expensive equipment and expertise for operation. Hence, for the purpose of rapid, high throughput screening and point-of-care diagnosis, researchers are miniaturizing sandwich ELISA procedures on Lab-on-a-Chip and Lab-on-Compact Disc (LOCD) platforms. This paper presents a novel integrated device to detect and interpret the ELISA test results on a LOCD platform. The system applies absorption spectrophotometry to measure the absorbance (optical density) of the sample using a monochromatic light source and optical sensor. The device performs automated analysis of the results and presents absorbance values and diagnostic test results via a graphical display or via Bluetooth to a smartphone platform which also acts as controller of the device. The efficacy of the device was evaluated by performing dengue antibody IgG ELISA on 64 hospitalized patients suspected of dengue. The results demonstrate high accuracy of the device, with 95% sensitivity and 100% specificity in detection when compared with gold standard commercial ELISA microplate readers. This sensor platform represents a significant step towards establishing ELISA as a rapid, inexpensive and automatic testing method for the purpose of point-of-care-testing (POCT) in resource-limited settings. PMID:25993517

Diagnostic Profiles: A Standard Setting Method for Use with a Cognitive Diagnostic Model

ERIC Educational Resources Information Center

Skaggs, Gary; Hein, Serge F.; Wilkins, Jesse L. M.

2016-01-01

This article introduces the Diagnostic Profiles (DP) standard setting method for setting a performance standard on a test developed from a cognitive diagnostic model (CDM), the outcome of which is a profile of mastered and not-mastered skills or attributes rather than a single test score. In the DP method, the key judgment task for panelists is a…

Defining Characteristics of Diagnostic Classification Models and the Problem of Retrofitting in Cognitive Diagnostic Assessment

ERIC Educational Resources Information Center

Gierl, Mark J.; Cui, Ying

2008-01-01

One promising application of diagnostic classification models (DCM) is in the area of cognitive diagnostic assessment in education. However, the successful application of DCM in educational testing will likely come with a price--and this price may be in the form of new test development procedures and practices required to yield data that satisfy…

Cost Implications of Value-Based Pricing for Companion Diagnostic Tests in Precision Medicine.

PubMed

Zaric, Gregory S

2016-07-01

Many interpretations of personalized medicine, also referred to as precision medicine, include discussions of companion diagnostic tests that allow drugs to be targeted to those individuals who are most likely to benefit or that allow treatment to be designed in a way such that individuals who are unlikely to benefit do not receive treatment. Many authors have commented on the clinical and competitive implications of companion diagnostics, but there has been relatively little formal analysis of the cost implications of companion diagnostics, although cost reduction is often cited as a significant benefit of precision medicine. We investigate the potential impact on costs of precision medicine implemented through the use of companion diagnostics. We develop a framework in which the costs of companion diagnostic tests are determined by considerations of profit maximization and cost effectiveness. We analyze four scenarios that are defined by the incremental cost-effectiveness ratio of the new drug in the absence of a companion diagnostic test. We find that, in most scenarios, precision medicine strategies based on companion diagnostics should be expected to lead to increases in costs in the short term and that costs would fall only in a limited number of situations.

How to conduct a high-quality original study on a diagnostic research topic.

PubMed

Yao, Xiaomei; Vella, Emily

2017-09-01

As health research methodologists and journal reviewers, we noticed that the methodological rigor of many publications on diagnostic or prognostic topics in the medical literature could be improved. We present a concise and clear series of reviews to help clinicians and health researchers to master the basic key components of how to conduct a high-quality original study or systematic review on a diagnostic or prognostic research topic from a methodological perspective. This is the first review of the series, which focuses on how to conduct a high-quality diagnostic study. We are introducing four aspects: clarifying the objectives; generating an appropriate research question; planning the study design; and reporting and analyzing data. This review highlights that diagnostic test accuracy outcomes are surrogates for patient outcomes, a diagnostic test has three roles, the "PIRO" components should be included in a diagnostic research question, a new study should be registered, multiple index tests can be compared in one study, and prevalence affects test accuracy outcomes. This review also emphasizes reporting any thresholds, calculating sample size, and performing a two-by-three table to calculate diagnostic outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

European Thyroid Association Guidelines regarding Thyroid Nodule Molecular Fine-Needle Aspiration Cytology Diagnostics.

PubMed

Paschke, Ralf; Cantara, Silvia; Crescenzi, Anna; Jarzab, Barbara; Musholt, Thomas J; Sobrinho Simoes, Manuel

2017-07-01

Molecular fine-needle aspiration (FNA) cytology diagnostics has the potential to address the inherent limitation of FNA cytology which is an indeterminate (atypia of undetermined significance/follicular lesion of undetermined significance follicular neoplasm) cytology. Because of the emerging role of molecular FNA cytology diagnostics, the European Thyroid Association convened a panel of international experts to review methodological aspects, indications, results, and limitations of molecular FNA cytology diagnostics. The panel reviewed the evidence for the diagnostic value of mutation panel assessment (including at least BRAF , NRAS , HRAS , KRAS , PAX8/PPARG , RET/PTC ) of targeted next generation sequencing and of a microarray gene expression classifier (GEC) test in the diagnostic assessment of an indeterminate cytology thyroid nodule. Moreover, possible surgical consequences of molecular FNA diagnostic results of thyroid nodules and the evidence that analysis of a molecular FNA diagnostic panel of somatic mutations or a microarray GEC test can alter the follow-up were reviewed. Molecular tests may help clinicians to drive patient care and the surgical decision if the analysis is performed in specialized laboratories. These molecular tests require standardization of performance characteristics and appropriate calibration as well as analytic validation before clinical interpretation.

European Thyroid Association Guidelines regarding Thyroid Nodule Molecular Fine-Needle Aspiration Cytology Diagnostics

PubMed Central

Paschke, Ralf; Cantara, Silvia; Crescenzi, Anna; Jarzab, Barbara; Musholt, Thomas J.; Sobrinho Simoes, Manuel

2017-01-01

Molecular fine-needle aspiration (FNA) cytology diagnostics has the potential to address the inherent limitation of FNA cytology which is an indeterminate (atypia of undetermined significance/follicular lesion of undetermined significance follicular neoplasm) cytology. Because of the emerging role of molecular FNA cytology diagnostics, the European Thyroid Association convened a panel of international experts to review methodological aspects, indications, results, and limitations of molecular FNA cytology diagnostics. The panel reviewed the evidence for the diagnostic value of mutation panel assessment (including at least BRAF, NRAS, HRAS, KRAS, PAX8/PPARG, RET/PTC) of targeted next generation sequencing and of a microarray gene expression classifier (GEC) test in the diagnostic assessment of an indeterminate cytology thyroid nodule. Moreover, possible surgical consequences of molecular FNA diagnostic results of thyroid nodules and the evidence that analysis of a molecular FNA diagnostic panel of somatic mutations or a microarray GEC test can alter the follow-up were reviewed. Molecular tests may help clinicians to drive patient care and the surgical decision if the analysis is performed in specialized laboratories. These molecular tests require standardization of performance characteristics and appropriate calibration as well as analytic validation before clinical interpretation. PMID:28785538

Low Energy X-Ray and Electron Physics and Technology for High-Temperature Plasma Diagnostics

DTIC Science & Technology

1987-10-01

This program in low-energy x-ray physics and technology has expanded into a major program with the principal objective of supporting research and application programs at the new large x-ray source facilities, particularly the high temperature plasma and synchrotron radiation sources. This program addresses the development of absolute x-ray diagnostics for the fusion energy and x-ray laser research and development. The new laboratory includes five specially designed

Plasma Radiation Source Development Program

DTIC Science & Technology

2006-03-01

shell mass distributions perform belter than thin shells. The dual plenum, double shell load has unique diagnostic features that enhance our...as implosion time increases. 13. SUBJECT TERMS Zpinch x-ray diagnostics Rayleigh-Taylor instability pulsed-power x-ray spectroscopy supersonic...feature permits some very useful diagnostics that shed light on critical details of the implosion process. See Section 3 for details. We have

Towards novel compact laser sources for non-invasive diagnostics and treatment

NASA Astrophysics Data System (ADS)

Rafailov, Edik U.; Litvinova, Karina S.; Sokolovski, Sergei G.

2015-08-01

An important field of application of lasers is biomedical optics. Here, they offer great utility for diagnosis, therapy and surgery. For the development of novel methods of laser-based biomedical diagnostics careful study of light propagation in biological tissues is necessary to enhance our understanding of the optical measurements undertaken, increase research and development capacity and the diagnostic reliability of optical technologies. Ultimately, fulfilling these requirements will increase uptake in clinical applications of laser based diagnostics and therapeutics. To address these challenges informative biomarkers relevant to the biological and physiological function or disease state of the organism must be selected. These indicators are the results of the analysis of tissues and cells, such as blood. For non-invasive diagnostics peripheral blood, cells and tissue can potentially provide comprehensive information on the condition of the human organism. A detailed study of the light scattering and absorption characteristics can quickly detect physiological and morphological changes in the cells due to thermal, chemical, antibiotic treatments, etc [1-5]. The selection of a laser source to study the structure of biological particles also benefits from the fact that gross pathological changes are not induced and diagnostics make effective use of the monochromatic directional coherence properties of laser radiation.

How patients navigate the diagnostic ecosystem in a fragmented health system: a qualitative study from India

PubMed Central

Yellapa, Vijayashree; Devadasan, Narayanan; Krumeich, Anja; Pant Pai, Nitika; Vadnais, Caroline; Pai, Madhukar; Engel, Nora

2017-01-01

ABSTRACT Background: Depending on a country’s diagnostic infrastructure, patients and providers play different roles in ensuring that correct and timely diagnosis is made. However, little is known about the work done by patients in accessing diagnostic services and completing the ‘test and treat’ loop. Objective: To address this knowledge gap, we traced the diagnostic journeys of patients with tuberculosis, diabetes, hypertension and typhoid, and examined the work they had to do to arrive at a diagnosis. Methods: This paper draws on a qualitative study, which included 78 semi-structured interviews and 13 focus group discussions with patients, public and private healthcare providers, community health workers, test manufacturers, laboratory technicians, program managers and policymakers. Data were collected between January and June 2013 in rural and urban Karnataka, South India, as part of a larger project on barriers to point-of-care testing. We reconstructed patient diagnostic processes retrospectively and analyzed emerging themes and patterns. Results: The journey to access diagnostic services requires a high level of involvement and immense work from patients and/or their caretakers. This process entails overcoming cost and distance, negotiating social relations, continuously making sense of their illness and diagnosis, producing and transporting samples, dealing with the social consequences of diagnosis, and returning results to the treating provider. The quality and content of interactions with providers were crucial for completion of test and treat loops. If the tasks became overwhelming, patients opted out, delayed being tested, switched providers and/or reverted to self-testing or self-treatment practices. Conclusion: Our study demonstrated how difficult it can be for patients to complete diagnostic journeys and how the health system works as far as diagnostics are concerned. If new point-of-care tests are to be implemented successfully, policymakers, program officers and test developers need to find ways to ease patient navigation through diagnostic services. PMID:28762894

Multiple tests for wind turbine fault detection and score fusion using two- level multidimensional scaling (MDS)

NASA Astrophysics Data System (ADS)

Ye, Xiang; Gao, Weihua; Yan, Yanjun; Osadciw, Lisa A.

2010-04-01

Wind is an important renewable energy source. The energy and economic return from building wind farms justify the expensive investments in doing so. However, without an effective monitoring system, underperforming or faulty turbines will cause a huge loss in revenue. Early detection of such failures help prevent these undesired working conditions. We develop three tests on power curve, rotor speed curve, pitch angle curve of individual turbine. In each test, multiple states are defined to distinguish different working conditions, including complete shut-downs, under-performing states, abnormally frequent default states, as well as normal working states. These three tests are combined to reach a final conclusion, which is more effective than any single test. Through extensive data mining of historical data and verification from farm operators, some state combinations are discovered to be strong indicators of spindle failures, lightning strikes, anemometer faults, etc, for fault detection. In each individual test, and in the score fusion of these tests, we apply multidimensional scaling (MDS) to reduce the high dimensional feature space into a 3-dimensional visualization, from which it is easier to discover turbine working information. This approach gains a qualitative understanding of turbine performance status to detect faults, and also provides explanations on what has happened for detailed diagnostics. The state-of-the-art SCADA (Supervisory Control And Data Acquisition) system in industry can only answer the question whether there are abnormal working states, and our evaluation of multiple states in multiple tests is also promising for diagnostics. In the future, these tests can be readily incorporated in a Bayesian network for intelligent analysis and decision support.

External quality assurance for HIV point-of-care testing in Africa: A collaborative country-partner approach to strengthen diagnostic services

PubMed Central

2016-01-01

It is important to consider the role of diagnostics and the critical need for quality diagnostics services in resource-limited settings. Accurate diagnostic tests play a key role in patient management and the prevention and control of most infectious diseases. As countries plan for implementation of HIV early infant diagnosis and viral load point-of-care testing, the London School of Hygiene & Tropical Medicine has worked with countries and partners with an interest in external quality assurance to support quality point-of-care testing on the continent. Through a series of collaborative consultations and workshops, the London School of Hygiene & Tropical Medicine has gathered lessons learned, tools, and resources and developed quality assurance models that will support point-of-care testing. The London School of Hygiene & Tropical Medicine is committed to the continued advancement of laboratory diagnostics in Africa and quality laboratory services and point-of-care testing. PMID:28879132

10 CFR 35.500 - Use of sealed sources for diagnosis.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Use of sealed sources for diagnosis. 35.500 Section 35.500 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Sealed Sources for Diagnosis § 35.500 Use of sealed sources for diagnosis. A licensee shall use only sealed sources for diagnostic...

WE-AB-206-02: ACR Ultrasound Accreditation: Requirements and Pitfalls

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

Walter, J.

The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. The goal of this ultrasound hands-on workshop is to demonstrate quality control (QC) testing in diagnostic ultrasound and to provide updates in ACR ultrasound accreditation requirements. The first half of this workshop will include two presentations reviewing diagnostic ultrasound QA/QC and ACR ultrasound accreditation requirements. The second half of the workshop will include live demonstrations of basic QC tests. An array of ultrasound testing phantoms and ultrasound scanners will be available for attendees to learn diagnostic ultrasound QC in a hands-on environmentmore » with live demonstrations and on-site instructors. The targeted attendees are medical physicists in diagnostic imaging. Learning Objectives: Gain familiarity with common elements of a QA/QC program for diagnostic ultrasound imaging dentify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools Learn ACR ultrasound accreditation requirements Jennifer Walter is an employee of American College of Radiology on Ultrasound Accreditation.« less

Market assessment of tuberculosis diagnostics in Brazil in 2012.

PubMed

2014-01-01

Improved diagnostics for the diagnosis of tuberculosis (TB) are urgently needed. However, test developers and investors require market size data to support new product development. This study assessed the served available market for TB diagnostics in Brazil in 2012 and the market segmentation in the public and private sectors. Data were collected on test volumes done in the public and private sectors for the diagnosis of latent and active TB, drug susceptibility testing and treatment follow-up. Tests included were tuberculin skin tests, interferon-gamma releases assays, smear microscopy, solid and liquid cultures, nucleic acid amplification tests and phenotypic drug susceptibility tests. The data were collected by means of an electronic survey via the Brazilian State laboratories and from sales information provided by manufacturers. Test costs for the public sector were calculated using a components approach, while costs for the private sector were based on prices paid by patients. The overall market value (expenditure) for the entire country was calculated using the public sector test costs. During 2012, an estimated total of 2.4 million TB diagnostic tests were done in Brazil, resulting in an estimated overall market value of USD 17.2 million. The public sector accounted for 91% of the test volumes and 88% of the market value. Smear microscopy was the most commonly test (n = 1.3 million; 55% of total) at an estimated value of USD 3.7 million. Culture overall (n = 302,761) represented 13% of test volumes and 40% (USD 6.9 million) of the market value. On average, USD 208 was spent on TB diagnostics for every notified TB patient in Brazil, in 2012. The TB diagnostics market value in Brazil in 2012 was over USD 17 million. These study results will help test developers to understand the current and potential market for replacement or add-on diagnostic technologies.

Market Assessment of Tuberculosis Diagnostics in Brazil in 2012

PubMed Central

2014-01-01

Background Improved diagnostics for the diagnosis of tuberculosis (TB) are urgently needed. However, test developers and investors require market size data to support new product development. This study assessed the served available market for TB diagnostics in Brazil in 2012 and the market segmentation in the public and private sectors. Methods Data were collected on test volumes done in the public and private sectors for the diagnosis of latent and active TB, drug susceptibility testing and treatment follow-up. Tests included were tuberculin skin tests, interferon-gamma releases assays, smear microscopy, solid and liquid cultures, nucleic acid amplification tests and phenotypic drug susceptibility tests. The data were collected by means of an electronic survey via the Brazilian State laboratories and from sales information provided by manufacturers. Test costs for the public sector were calculated using a components approach, while costs for the private sector were based on prices paid by patients. The overall market value (expenditure) for the entire country was calculated using the public sector test costs. Results During 2012, an estimated total of 2.4 million TB diagnostic tests were done in Brazil, resulting in an estimated overall market value of USD 17.2 million. The public sector accounted for 91% of the test volumes and 88% of the market value. Smear microscopy was the most commonly test (n = 1.3 million; 55% of total) at an estimated value of USD 3.7 million. Culture overall (n = 302,761) represented 13% of test volumes and 40% (USD 6.9 million) of the market value. On average, USD 208 was spent on TB diagnostics for every notified TB patient in Brazil, in 2012. Conclusion The TB diagnostics market value in Brazil in 2012 was over USD 17 million. These study results will help test developers to understand the current and potential market for replacement or add-on diagnostic technologies. PMID:25099237

The role of neurologists and diagnostic tests in the management of distal symmetric polyneuropathy

PubMed Central

Callaghan, Brian C.; Kerber, Kevin A.; Lisabeth, Lynda L.; Morgenstern, Lewis B.; Longoria, Ruth; Rodgers, Ann; Longwell, Paxton; Feldman, Eva L.

2014-01-01

Importance Distal symmetric polyneuropathy (DSP) is a prevalent condition resulting in high costs from diagnostic testing. However, the role of neurologists and diagnostic tests on patient care is unknown. Objective To determine how often neurologists and diagnostic tests influence the diagnosis and management of DSP patients in a community setting. Design We utilized a validated case-capture method (ICD-9 screening technique with subsequent medical chart abstraction) to identify patients with a new DSP diagnosis (retrospective cohort). Using a structured data abstraction process, diagnostic testing, diagnoses rendered (before and after testing), and subsequent management were recorded. Setting Community neurologist’s outpatient offices in Corpus Christi, Texas. Participants Patients meeting the Toronto consensus criteria for probable DSP. Main Outcome Measure Changes in etiology and management after diagnostic testing by neurologists. Results Between 1/1/2010–3/31/2011, we identified 458 DSP patients followed for mean (SD) 435.3 (44.1) days. Neurologists identified a cause of DSP in 63.5% of cases prior to their diagnostic testing. Seventy-one patients (15.5%) had a new DSP cause discovered after testing by neurologists. The most common new diagnoses were pre-diabetes (N=28), B12 deficiency (N=20), diabetes (N=8), and thyroid disease (N=8). Management changes were common (63.1%), usually related to neuropathic pain management (77.5%). Disease modifying management changes occurred in 24.7% with diabetes management (N=45), starting vitamins (N=39), advising diet/exercise (N=33), and adjusting thyroid medications (N=10) the most common. Electrodiagnostic testing and MRIs of the neuroaxis rarely led to management changes. Conclusions and Relevance Neurologists diagnosed the cause of DSP in almost two-thirds of patients prior to their diagnostic testing. Inexpensive blood tests for diabetes, thyroid dysfunction, and B12 deficiency, allowed neurologists to identify a new etiology in 15.5% of patients. In contrast, expensive electrodiagnostic tests and MRIs rarely changed patient care. Neurologists also frequently made pain medication changes utilizing best evidence medications. PMID:25048157

Noninvasive fetal RhCE genotyping from maternal blood.

PubMed

Geifman-Holtzman, O; Grotegut, C A; Gaughan, J P; Holtzman, E J; Floro, C; Hernandez, E

2009-01-01

The successful prevention of RhD disease has brought attention to other red blood cells' antigens causing alloimmunisation including RhC/c and RhE/e. Prenatal diagnosis of fetal Rh genotype from maternal blood is in clinical use in Europe but not in the USA. To estimate the collective reported diagnostic accuracy of fetal RhCE genotyping from peripheral maternal blood and compare the results of genotyping when fetal cells and free fetal DNA (FfDNA) are used. English-written literature describing fetal RhCE determination from maternal blood using fetal cells or FfDNA was performed using medical subject headings and text words. The sources included Pubmed (1966-2007), Ovid (1966-2007), CINAHL, The Cochrane Library, ACP Journal Club and OCLC. Key words were prenatal diagnosis, fetal RhCE, fetal DNA in maternal blood and alloimmunisation. A study was considered eligible if it described fetal RhCE type determination using maternal peripheral blood reported in the English literature. Abstracts were excluded. From each study, we determined the number of samples tested, fetal RhCE genotype, the source of the fetal DNA, gestational age, presence of alloimmunisation and confirmation of fetal RhCE type. Exclusions and inclusions were noted. We calculated composite estimates of accuracy using a weighted random effects model. We assessed the papers against an international quality, STARD checklist which is standards for reporting studies of diagnostic accuracy. We identified 20 protocols in six English-written publications reporting fetal RhC/c (seven protocols) and/or E/e (13 protocols) genotyping using DNA obtained from maternal blood for a total of 369 samples. For RhC/c, 176 samples were tested and for RhE/e, 193 samples were tested. Accuracy was determined for each study and for all studies. The combined accuracy of fetal genotype was 96.3% for RhC/c and 98.2% for RhE/e. Only a few samples of the sorted cells were found to be a source for accurate diagnosis, but plasma was consistently the best source of fetal RhCE genotyping in 147/147 (100%) for RhC/c and 168/168 (100%) for RhE/e. The combined accuracy of noninvasive fetal RhC/c or RhE/e determination using maternal peripheral blood is 96.3% and 98.2%, respectively. FfDNA in maternal plasma is a better source for genotyping reported to be 100% correct for both RHCE genotypes. Further studies and reports of accuracy from laboratories performing the tests are required before prenatal determination of fetal RhC/c or RhE/e genotypes from maternal blood can safely replace the current methods used in the management of the RhC/c or RhE alloimmunised pregnancies.

42 CFR 414.50 - Physician or other supplier billing for diagnostic tests performed or interpreted by a physician...

Code of Federal Regulations, 2011 CFR

2011-10-01

...) or professional component (PC) of a diagnostic test that was ordered by the physician or other... behalf of the beneficiary) for the TC or PC of the diagnostic test may not exceed the lowest of the... who supervised the TC, and with respect to the PC, the performing supplier is the physician who...

An Overview of Models of Speaking Performance and Its Implications for the Development of Procedural Framework for Diagnostic Speaking Tests

ERIC Educational Resources Information Center

Zhao, Zhongbao

2013-01-01

This paper aims at developing a procedural framework for the development and validation of diagnostic speaking tests. The researcher reviews the current available models of speaking performance, analyzes the distinctive features and then points out the implications for the development of a procedural framework for diagnostic speaking tests. On…

9 CFR 130.16 - User fees for veterinary diagnostic serology tests performed at NVSL (excluding FADDL) or at...

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false User fees for veterinary diagnostic serology tests performed at NVSL (excluding FADDL) or at authorized sites. 130.16 Section 130.16 Animals... USER FEES § 130.16 User fees for veterinary diagnostic serology tests performed at NVSL (excluding...

9 CFR 130.17 - User fees for other veterinary diagnostic laboratory tests performed at NVSL (excluding FADDL) or...

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false User fees for other veterinary... FEES USER FEES § 130.17 User fees for other veterinary diagnostic laboratory tests performed at NVSL (excluding FADDL) or at authorized sites. (a) User fees for veterinary diagnostics tests performed at the...

9 CFR 130.17 - User fees for other veterinary diagnostic laboratory tests performed at NVSL (excluding FADDL) or...

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for other veterinary... FEES USER FEES § 130.17 User fees for other veterinary diagnostic laboratory tests performed at NVSL (excluding FADDL) or at authorized sites. (a) User fees for veterinary diagnostics tests performed at the...

9 CFR 130.16 - User fees for veterinary diagnostic serology tests performed at NVSL (excluding FADDL) or at...

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for veterinary diagnostic serology tests performed at NVSL (excluding FADDL) or at authorized sites. 130.16 Section 130.16 Animals... USER FEES § 130.16 User fees for veterinary diagnostic serology tests performed at NVSL (excluding...

30 CFR 250.525 - What do I submit if my casing diagnostic test requires action?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What do I submit if my casing diagnostic test... INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Completion Operations Casing Pressure Management § 250.525 What do I submit if my casing diagnostic test...

Assessing Diagnostic Tests II: Grading on a Curve.

PubMed

Jupiter, Daniel C

2015-01-01

In this Investigators' Corner, I continue discussing how to introduce and assess new diagnostic tests to replace older tests that are considered gold standards. Specifically, I talk about how to assess a "family" of diagnostics, and how to choose an optimal "family member." Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

A diagnostic approach to hemochromatosis

PubMed Central

Tavill, Anthony S; Adams, Paul C

2006-01-01

In the present clinical review, a diagnostic approach to hemochromatosis is discussed from the perspective of two clinicians with extensive experience in this area. The introduction of genetic testing and large-scale population screening studies have broadened our understanding of the clinical expression of disease and the utility of biochemical iron tests for the detection of disease and for the assessment of disease severity. Liver biopsy has become more of a prognostic test than a diagnostic test. The authors offer a stepwise, diagnostic algorithm based on current evidence-based data, that they regard as most cost-effective. An early diagnosis can lead to phlebotomy therapy to prevent the development of cirrhosis. PMID:16955151