Using Real-time Event Tracking Sensitivity Analysis to Overcome Sensor Measurement Uncertainties of Geo-Information Management in Drilling Disasters

NASA Astrophysics Data System (ADS)

Tavakoli, S.; Poslad, S.; Fruhwirth, R.; Winter, M.

2012-04-01

This paper introduces an application of a novel EventTracker platform for instantaneous Sensitivity Analysis (SA) of large scale real-time geo-information. Earth disaster management systems demand high quality information to aid a quick and timely response to their evolving environments. The idea behind the proposed EventTracker platform is the assumption that modern information management systems are able to capture data in real-time and have the technological flexibility to adjust their services to work with specific sources of data/information. However, to assure this adaptation in real time, the online data should be collected, interpreted, and translated into corrective actions in a concise and timely manner. This can hardly be handled by existing sensitivity analysis methods because they rely on historical data and lazy processing algorithms. In event-driven systems, the effect of system inputs on its state is of value, as events could cause this state to change. This 'event triggering' situation underpins the logic of the proposed approach. Event tracking sensitivity analysis method describes the system variables and states as a collection of events. The higher the occurrence of an input variable during the trigger of event, the greater its potential impact will be on the final analysis of the system state. Experiments were designed to compare the proposed event tracking sensitivity analysis with existing Entropy-based sensitivity analysis methods. The results have shown a 10% improvement in a computational efficiency with no compromise for accuracy. It has also shown that the computational time to perform the sensitivity analysis is 0.5% of the time required compared to using the Entropy-based method. The proposed method has been applied to real world data in the context of preventing emerging crises at drilling rigs. One of the major purposes of such rigs is to drill boreholes to explore oil or gas reservoirs with the final scope of recovering the content of such reservoirs; both in onshore regions as well as in offshore regions. Drilling a well is always guided by technical, economic and security constraints to prevent crew, equipment and environment from injury, damage and pollution. Although risk assessment and local practice provides a high degree of security, uncertainty is given by the behaviour of the formation which may cause crucial situations at the rig. To overcome such uncertainties real-time sensor measurements form a base to predict and thus prevent such crises, the proposed method supports the identification of the data necessary for that.

Real-time PCR for type-specific identification of herpes simplex in clinical samples: evaluation of type-specific results in the context of CNS diseases.

PubMed

Meylan, Sylvain; Robert, Daniel; Estrade, Christine; Grimbuehler, Valérie; Péter, Olivier; Meylan, Pascal R; Sahli, Roland

2008-02-01

HSV-1 and HSV-2 cause CNS infections of dissimilar clinico-pathological characteristics with prognostic and therapeutic implications. To validate a type-specific real-time PCR that uses MGB/LNA Taqman probes and to review the virologico-clinical data of 25 eligible patients with non-neonatal CNS infections. This real-time PCR was evaluated against conventional PCR (26 CSF and 20 quality controls), and LightCycler assay (51 mucocutaneous, 8 CSF and 32 quality controls) and culture/immunofluorescence (75 mucocutaneous) to assess typing with independent methods. Taqman real-time PCR detected 240 HSV genomes per ml CSF, a level appropriate for the management of patients, and provided unambiguous typing for the 104 positive (62 HSV-1 and 42 HSV-2) out the 160 independent clinical samples tested. HSV type diagnosed by Taqman real-time PCR predicted final diagnosis (meningitis versus encephalitis/meningoencephalitis, p<0.001) in 24/25 patients at time of presentation, in contrast to clinical evaluation. Our real-time PCR, as a sensitive and specific means for type-specific HSV diagnosis, provided rapid prognostic information for patient management.

Inferring Human Activity in Mobile Devices by Computing Multiple Contexts.

PubMed

Chen, Ruizhi; Chu, Tianxing; Liu, Keqiang; Liu, Jingbin; Chen, Yuwei

2015-08-28

This paper introduces a framework for inferring human activities in mobile devices by computing spatial contexts, temporal contexts, spatiotemporal contexts, and user contexts. A spatial context is a significant location that is defined as a geofence, which can be a node associated with a circle, or a polygon; a temporal context contains time-related information that can be e.g., a local time tag, a time difference between geographical locations, or a timespan; a spatiotemporal context is defined as a dwelling length at a particular spatial context; and a user context includes user-related information that can be the user's mobility contexts, environmental contexts, psychological contexts or social contexts. Using the measurements of the built-in sensors and radio signals in mobile devices, we can snapshot a contextual tuple for every second including aforementioned contexts. Giving a contextual tuple, the framework evaluates the posteriori probability of each candidate activity in real-time using a Naïve Bayes classifier. A large dataset containing 710,436 contextual tuples has been recorded for one week from an experiment carried out at Texas A&M University Corpus Christi with three participants. The test results demonstrate that the multi-context solution significantly outperforms the spatial-context-only solution. A classification accuracy of 61.7% is achieved for the spatial-context-only solution, while 88.8% is achieved for the multi-context solution.

Spread spectrum time-resolved diffuse optical measurement system for enhanced sensitivity in detecting human brain activity

NASA Astrophysics Data System (ADS)

Mehta, Kalpesh; Hasnain, Ali; Zhou, Xiaowei; Luo, Jianwen; Penney, Trevor B.; Chen, Nanguang

2017-04-01

Diffuse optical spectroscopy (DOS) and imaging methods have been widely applied to noninvasive detection of brain activity. We have designed and implemented a low cost, portable, real-time one-channel time-resolved DOS system for neuroscience studies. Phantom experiments were carried out to test the performance of the system. We further conducted preliminary human experiments and demonstrated that enhanced sensitivity in detecting neural activity in the cortex could be achieved by the use of late arriving photons.

Hidden Markov models for character recognition.

PubMed

Vlontzos, J A; Kung, S Y

1992-01-01

A hierarchical system for character recognition with hidden Markov model knowledge sources which solve both the context sensitivity problem and the character instantiation problem is presented. The system achieves 97-99% accuracy using a two-level architecture and has been implemented using a systolic array, thus permitting real-time (1 ms per character) multifont and multisize printed character recognition as well as handwriting recognition.

Dissociating Linguistic and Non-Linguistic Gesture Processing: Electrophysiological Evidence from American Sign Language

ERIC Educational Resources Information Center

Grosvald, Michael; Gutierrez, Eva; Hafer, Sarah; Corina, David

2012-01-01

A fundamental advance in our understanding of human language would come from a detailed account of how non-linguistic and linguistic manual actions are differentiated in real time by language users. To explore this issue, we targeted the N400, an ERP component known to be sensitive to semantic context. Deaf signers saw 120 American Sign Language…

Context sensitive formulations of antenna pattern correction and side lobe compensation for NOSS/LAMMR real time processing

NASA Technical Reports Server (NTRS)

Chin, R. T.; Beaudet, P. R.

1981-01-01

Large antenna multi-channel microwave radiometer (LAMMR) software specifications were written for LAMMR ground processing. There is a need to determine more computationally-efficient antenna temperature correction methods in compensating side lobe contributions especially near continents, islands and weather fronts. One of the major conclusions was that the antenna pattern corrections (APC) processes did not accomplish the implied goals of compensating for the antenna side lobe influences on brightness temperature. A-priori knowledge of land/water locations was shown to be needed and had to be incorporated in a context sensitive APC process if the artifacts caused by land presence is to be avoided. The high temperatures in land regions can severely bias the lower ocean response.

Securing Real-Time Sessions in an IMS-Based Architecture

NASA Astrophysics Data System (ADS)

Cennamo, Paolo; Fresa, Antonio; Longo, Maurizio; Postiglione, Fabio; Robustelli, Anton Luca; Toro, Francesco

The emerging all-IP mobile network infrastructures based on 3rd Generation IP Multimedia Subsystem philosophy are characterised by radio access technology independence and ubiquitous connectivity for mobile users. Currently, great focus is being devoted to security issues since most of the security threats presently affecting the public Internet domain, and the upcoming ones as well, are going to be suffered by mobile users in the years to come. While a great deal of research activity, together with standardisation efforts and experimentations, is carried out on mechanisms for signalling protection, very few integrated frameworks for real-time multimedia data protection have been proposed in a context of IP Multimedia Subsystem, and even fewer experimental results based on testbeds are available. In this paper, after a general overview of the security issues arising in an advanced IP Multimedia Subsystem scenario, a comprehensive infrastructure for real-time multimedia data protection, based on the adoption of the Secure Real-Time Protocol, is proposed; then, the development of a testbed incorporating such functionalities, including mechanisms for key management and cryptographic context transfer, and allowing the setup of Secure Real-Time Protocol sessions is presented; finally, experimental results are provided together with quantitative assessments and comparisons of system performances for audio sessions with and without the adoption of the Secure Real-Time Protocol framework.

Development of a highly sensitive one-tube nested real-time PCR for detecting Mycobacterium tuberculosis.

PubMed

Choi, Yeonim; Jeon, Bo-Young; Shim, Tae Sun; Jin, Hyunwoo; Cho, Sang-Nae; Lee, Hyeyoung

2014-12-01

Rapid, accurate detection of Mycobacterium tuberculosis is crucial in the diagnosis of tuberculosis (TB), but conventional diagnostic methods have limited sensitivity and specificity or are time consuming. A new highly sensitive nucleic acid amplification test, combined nested and real-time polymerase chain reaction (PCR) in a single tube (one-tube nested real-time PCR), was developed for detecting M. tuberculosis, which takes advantage of two PCR techniques, i.e., nested PCR and real-time PCR. One-tube nested real-time PCR was designed to have two sequential reactions with two sets of primers and dual probes for the insertion sequence (IS) 6110 sequence of M. tuberculosis in a single closed tube. The minimum limits of detection of IS6110 real-time PCR and IS6110 one-tube nested real-time PCR were 100 fg/μL and 1 fg/μL of M. tuberculosis DNA, respectively. AdvanSure TB/non-tuberculous mycobacteria (NTM) real-time PCR, IS6110 real-time PCR, and two-tube nested real-time PCR showed 100% sensitivity and 100% specificity for clinical M. tuberculosis isolates and NTM isolates. In comparison, the sensitivities of AdvanSure TB/NTM real-time PCR, single IS6110 real-time PCR, and one-tube nested real-time PCR were 91% (152/167), 94.6% (158/167), and 100% (167/167) for sputum specimens, respectively. In conclusion, IS6110 one-tube nested real-time PCR is useful for detecting M. tuberculosis due to its high sensitivity and simple manipulation. Copyright © 2014 Elsevier Inc. All rights reserved.

Use of quantitative real-time RT-PCR to investigate the correlation between viremia and viral shedding of canine distemper virus, and infection outcomes in experimentally infected dogs.

PubMed

Sehata, Go; Sato, Hiroaki; Ito, Toshihiro; Imaizumi, Yoshitaka; Noro, Taichi; Oishi, Eiji

2015-07-01

We used real-time RT-PCR and virus titration to examine canine distemper virus (CDV) kinetics in peripheral blood and rectal and nasal secretions from 12 experimentally infected dogs. Real-time RT-PCR proved extremely sensitive, and the correlation between the two methods for rectal and nasal (r=0.78, 0.80) samples on the peak day of viral RNA was good. Although the dogs showed diverse symptoms, viral RNA kinetics were similar; the peak of viral RNA in the symptomatic dogs was consistent with the onset of symptoms. These results indicate that real-time RT-PCR is sufficiently sensitive to monitor CDV replication in experimentally infected dogs regardless of the degree of clinical manifestation and suggest that the peak of viral RNA reflects active CDV replication.

Use of quantitative real-time RT-PCR to investigate the correlation between viremia and viral shedding of canine distemper virus, and infection outcomes in experimentally infected dogs

PubMed Central

SEHATA, Go; SATO, Hiroaki; ITO, Toshihiro; IMAIZUMI, Yoshitaka; NORO, Taichi; OISHI, Eiji

2015-01-01

We used real-time RT-PCR and virus titration to examine canine distemper virus (CDV) kinetics in peripheral blood and rectal and nasal secretions from 12 experimentally infected dogs. Real-time RT-PCR proved extremely sensitive, and the correlation between the two methods for rectal and nasal (r=0.78, 0.80) samples on the peak day of viral RNA was good. Although the dogs showed diverse symptoms, viral RNA kinetics were similar; the peak of viral RNA in the symptomatic dogs was consistent with the onset of symptoms. These results indicate that real-time RT-PCR is sufficiently sensitive to monitor CDV replication in experimentally infected dogs regardless of the degree of clinical manifestation and suggest that the peak of viral RNA reflects active CDV replication. PMID:25728411

Context-sensitive ecological momentary assessments; integrating real-time exposure measurements, data-analytics and health assessment using a smartphone application.

PubMed

van Wel, Luuk; Huss, Anke; Bachmann, Philipp; Zahner, Marco; Kromhout, Hans; Fröhlich, Jürg; Vermeulen, Roel

2017-06-01

Modern sensor technology makes it possible to collect vast amounts of environmental, behavioural and health data. These data are often linked to contextual information on for example exposure sources which is separately collected with considerable lag time, leading to complications in assessing transient and/or highly spatially variable environmental exposures. Context-Sensitive Ecological Momentary Assessments 1 (CS-EMAs) could be used to address this. We present a case study using radiofrequency-electromagnetic fields (RF-EMF) exposure as an example for implementing CS-EMA in environmental research. Participants were asked to install a custom application on their own smartphone and to wear an RF-EMF exposimeter for 48h. Questionnaires were triggered by the application based on a continuous data stream from the exposimeter. Triggers were divided into four categories: relative and absolute exposure levels, phone calls, and control condition. After the two days of use participants filled in an evaluation questionnaire. 74% of all CS-EMAs were completed, with an average time of 31s to complete a questionnaire once it was opened. Participants reported minimal influence on daily activities. There were no significant differences found between well-being and type of RF-EMF exposure. We show that a CS-EMA based method could be used in environmental research. Using several examples involving environmental stressors, we discuss both current and future applications of this methodology in studying potential health effects of environmental factors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of real-time SYBR green dengue assay with real-time taqman RT-PCR dengue assay and the conventional nested PCR for diagnosis of primary and secondary dengue infection

PubMed Central

Paudel, Damodar; Jarman, Richard; Limkittikul, Kriengsak; Klungthong, Chonticha; Chamnanchanunt, Supat; Nisalak, Ananda; Gibbons, Robert; Chokejindachai, Watcharee

2011-01-01

Background: Dengue fever and dengue hemorrhagic fever are caused by dengue virus. Dengue infection remains a burning problem of many countries. To diagnose acute dengue in the early phase we improve the low cost, rapid SYBR green real time assay and compared the sensitivity and specificity with real time Taqman® assay and conventional nested PCR assay. Aims: To develop low cost, rapid and reliable real time SYBR green diagnostic dengue assay and compare with Taqman real-time assay and conventional nested PCR (modified Lanciotti). Materials and Methods: Eight cultured virus strains were diluted in tenth dilution down to undetectable level by the PCR to optimize the primer, temperature (annealing, and extension and to detect the limit of detection of the assay. Hundred and ninety three ELISA and PCR proved dengue clinical samples were tested with real time SYBR® Green assay, real time Taqman® assay to compare the sensitivity and specificity. Results: Sensitivity and specificity of real time SYBR® green dengue assay (84% and 66%, respectively) was almost comparable to those (81% and 74%) of Taqman real time PCR dengue assay. Real time SYBR® green RT-PCR was equally sensitive in primary and secondary infection while real time Taqman was less sensitive in the secondary infection. Sensitivity of real time Taqman on DENV3 (87%) was equal to SYBR green real time PCR dengue assay. Conclusion: We developed low cost rapid diagnostic SYBR green dengue assay. Further study is needed to make duplex primer assay for the serotyping of dengue virus. PMID:22363089

Ratiometric activatable cell-penetrating peptides provide rapid in vivo readout of thrombin activation.

PubMed

Whitney, Michael; Savariar, Elamprakash N; Friedman, Beth; Levin, Rachel A; Crisp, Jessica L; Glasgow, Heather L; Lefkowitz, Roy; Adams, Stephen R; Steinbach, Paul; Nashi, Nadia; Nguyen, Quyen T; Tsien, Roger Y

2013-01-02

In real time: thrombin activation in vivo can be imaged in real time with ratiometric activatable cell penetrating peptides (RACPPs). RACPPs are designed to combine 1) dual-emission ratioing, 2) far red to infrared wavelengths for in vivo mammalian imaging, and 3) cleavage-dependent spatial localization. The most advanced RACPP uses norleucine (Nle)-TPRSFL as a linker that increases sensitivity to thrombin by about 90-fold. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Long term real-time monitoring of large alpine rockslides by GB-InSAR: mechanisms, triggers, scenario assessment and Early Warning

NASA Astrophysics Data System (ADS)

Crosta, G. B.; Agliardi, F.; Sosio, R.; Rivolta, C.; Leva, D.; Dei Cas, L.

2012-04-01

Large rockslides in alpine valleys can undergo catastrophic evolution, posing extraordinary risks to settlements, lives and critical infrastructures. These phenomena are controlled by a complex interplay of lithological, structural, hydrological and meteo-climatic factors, which eventually result in: complex triggering mechanisms and kinematics, highly variable activity, regressive to progressive trends with superimposed acceleration and deceleration periods related to rainfall and snowmelt. Managing large rockslide risk remains challenging, due the high uncertainty related to their geological model and dynamics. In this context, the most promising approach to constrain rockslide kinematics, establish correlations with triggering factors, and predict future displacements, velocity and acceleration, and eventually possible final collapse is based on the analysis and modelling of long-term series of monitoring data. More than traditional monitoring activities, remote sensing represents an important tool aimed at describing local rockslide displacements and kinematics, at distinguishing rates of activity, and providing real time data suitable for early warning. We analyze a long term monitoring dataset collected for a deep-seated rockslide (Ruinon, Lombardy, Italy), actively monitored since 1997 through an in situ monitoring network (topographic and GPS, wire extensometers and distometer baselines) and since 2006 by a ground based radar (GB-InSAR). Monitoring allowed to set-up and update the geological model, identify rockslide extent and geometry, analyze its sensitivity to seasonal changes and their impact on the reliability and EW potential of monitoring data. GB-InSAR data allowed to identify sub-areas with different behaviors associated to outcropping bedrock and thick debris cover, and to set-up a "virtual monitoring network" by a posteriori selection of critical locations. Resulting displacement time series provide a large amount of information even in debris-covered areas, where traditional monitoring fails. Such spatially-distributed, improved information, validated by selected ground-based measurements, allowed to establish new velocity thresholds for EW purposes. Relationships between rainfall and displacement rates allowed to identify different possible failure mechanisms and to constrain the applicability of rainfall EW thresholds. Comparison with temperature and snow melting time series allowed to clarify the sensitivity of the rockslide movement to these controlling factors. Finally, the recognition of the sensitivity to all these factors allowed us to accomplish a more complete hazard assessment by defining different failure scenarios and the associated triggering thresholds.

TaqMan based real time PCR assay targeting EML4-ALK fusion transcripts in NSCLC.

PubMed

Robesova, Blanka; Bajerova, Monika; Liskova, Kvetoslava; Skrickova, Jana; Tomiskova, Marcela; Pospisilova, Sarka; Mayer, Jiri; Dvorakova, Dana

2014-07-01

Lung cancer with the ALK rearrangement constitutes only a small fraction of patients with non-small cell lung cancer (NSCLC). However, in the era of molecular-targeted therapy, efficient patient selection is crucial for successful treatment. In this context, an effective method for EML4-ALK detection is necessary. We developed a new highly sensitive variant specific TaqMan based real time PCR assay applicable to RNA from formalin-fixed paraffin-embedded tissue (FFPE). This assay was used to analyze the EML4-ALK gene in 96 non-selected NSCLC specimens and compared with two other methods (end-point PCR and break-apart FISH). EML4-ALK was detected in 33/96 (34%) specimens using variant specific real time PCR, whereas in only 23/96 (24%) using end-point PCR. All real time PCR positive samples were confirmed with direct sequencing. A total of 46 specimens were subsequently analyzed by all three detection methods. Using variant specific real time PCR we identified EML4-ALK transcript in 17/46 (37%) specimens, using end-point PCR in 13/46 (28%) specimens and positive ALK rearrangement by FISH was detected in 8/46 (17.4%) specimens. Moreover, using variant specific real time PCR, 5 specimens showed more than one EML4-ALK variant simultaneously (in 2 cases the variants 1+3a+3b, in 2 specimens the variants 1+3a and in 1 specimen the variant 1+3b). In one case of 96 EML4-ALK fusion gene and EGFR mutation were detected. All simultaneous genetic variants were confirmed using end-point PCR and direct sequencing. Our variant specific real time PCR assay is highly sensitive, fast, financially acceptable, applicable to FFPE and seems to be a valuable tool for the rapid prescreening of NSCLC patients in clinical practice, so, that most patients able to benefit from targeted therapy could be identified. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Integration of real-time mapping technology in disaster relief distribution.

DOT National Transportation Integrated Search

2013-02-01

Vehicle routing for disaster relief distribution involves many challenges that distinguish this problem from those in commercial settings, given the time sensitive and resource constrained nature of relief activities. While operations research approa...

High-Speed Real-Time Resting-State fMRI Using Multi-Slab Echo-Volumar Imaging

PubMed Central

Posse, Stefan; Ackley, Elena; Mutihac, Radu; Zhang, Tongsheng; Hummatov, Ruslan; Akhtari, Massoud; Chohan, Muhammad; Fisch, Bruce; Yonas, Howard

2013-01-01

We recently demonstrated that ultra-high-speed real-time fMRI using multi-slab echo-volumar imaging (MEVI) significantly increases sensitivity for mapping task-related activation and resting-state networks (RSNs) compared to echo-planar imaging (Posse et al., 2012). In the present study we characterize the sensitivity of MEVI for mapping RSN connectivity dynamics, comparing independent component analysis (ICA) and a novel seed-based connectivity analysis (SBCA) that combines sliding-window correlation analysis with meta-statistics. This SBCA approach is shown to minimize the effects of confounds, such as movement, and CSF and white matter signal changes, and enables real-time monitoring of RSN dynamics at time scales of tens of seconds. We demonstrate highly sensitive mapping of eloquent cortex in the vicinity of brain tumors and arterio-venous malformations, and detection of abnormal resting-state connectivity in epilepsy. In patients with motor impairment, resting-state fMRI provided focal localization of sensorimotor cortex compared with more diffuse activation in task-based fMRI. The fast acquisition speed of MEVI enabled segregation of cardiac-related signal pulsation using ICA, which revealed distinct regional differences in pulsation amplitude and waveform, elevated signal pulsation in patients with arterio-venous malformations and a trend toward reduced pulsatility in gray matter of patients compared with healthy controls. Mapping cardiac pulsation in cortical gray matter may carry important functional information that distinguishes healthy from diseased tissue vasculature. This novel fMRI methodology is particularly promising for mapping eloquent cortex in patients with neurological disease, having variable degree of cooperation in task-based fMRI. In conclusion, ultra-high-real-time speed fMRI enhances the sensitivity of mapping the dynamics of resting-state connectivity and cerebro-vascular pulsatility for clinical and neuroscience research applications. PMID:23986677

Maternal sensitivity and adrenocortical functioning across infancy and toddlerhood: Physiological adaptation to context?

PubMed Central

BERRY, DANIEL; BLAIR, CLANCY; WILLOUGHBY, MICHAEL; GRANGER, DOUGLAS A.; MILLS-KOONCE, W. ROGER

2018-01-01

Theory suggests that early experiences may calibrate the “threshold activity” of the hypothalamus–pituitary–adrenal axis in childhood. Particularly challenging or particularly supportive environments are posited to manifest in heightened physiological sensitivity to context. Using longitudinal data from the Family Life Project (N = 1,292), we tested whether links between maternal sensitivity and hypothalamus–pituitary–adrenal axis activity aligned with these predictions. Specifically, we tested whether the magnitude of the within-person relation between maternal sensitivity and children’s cortisol levels, a proxy for physiological sensitivity to context, was especially pronounced for children who typically experienced particularly low or high levels of maternal sensitivity over time. Our results were consistent with these hypotheses. Between children, lower levels of mean maternal sensitivity (7–24 months) were associated with higher mean cortisol levels across this period (measured as a basal sample collected at each visit). However, the magnitude and direction of the within-person relation was contingent on children’s average levels of maternal sensitivity over time. Increases in maternal sensitivity were associated with contemporaneous cortisol decreases for children with typically low-sensitive mothers, whereas sensitivity increases were associated with cortisol increases for children with typically high-sensitive mothers. No within-child effects were evident at moderate levels of maternal sensitivity. PMID:27065311

Prediction-error in the context of real social relationships modulates reward system activity.

PubMed

Poore, Joshua C; Pfeifer, Jennifer H; Berkman, Elliot T; Inagaki, Tristen K; Welborn, Benjamin L; Lieberman, Matthew D

2012-01-01

The human reward system is sensitive to both social (e.g., validation) and non-social rewards (e.g., money) and is likely integral for relationship development and reputation building. However, data is sparse on the question of whether implicit social reward processing meaningfully contributes to explicit social representations such as trust and attachment security in pre-existing relationships. This event-related fMRI experiment examined reward system prediction-error activity in response to a potent social reward-social validation-and this activity's relation to both attachment security and trust in the context of real romantic relationships. During the experiment, participants' expectations for their romantic partners' positive regard of them were confirmed (validated) or violated, in either positive or negative directions. Primary analyses were conducted using predefined regions of interest, the locations of which were taken from previously published research. Results indicate that activity for mid-brain and striatal reward system regions of interest was modulated by social reward expectation violation in ways consistent with prior research on reward prediction-error. Additionally, activity in the striatum during viewing of disconfirmatory information was associated with both increases in post-scan reports of attachment anxiety and decreases in post-scan trust, a finding that follows directly from representational models of attachment and trust.

CortiQ-based Real-Time Functional Mapping for Epilepsy Surgery.

PubMed

Kapeller, Christoph; Korostenskaja, Milena; Prueckl, Robert; Chen, Po-Ching; Lee, Ki Heyeong; Westerveld, Michael; Salinas, Christine M; Cook, Jane C; Baumgartner, James E; Guger, Christoph

2015-06-01

To evaluate the use of the cortiQ-based mapping system (g.tec medication engineering GmbH, Austria) for real-time functional mapping (RTFM) and to compare it to results from electrical cortical stimulation mapping (ESM) and functional magnetic resonance imaging (fMRI). Electrocorticographic activity was recorded in 3 male patients with intractable epilepsy by using cortiQ mapping system and analyzed in real time. Activation related to motor, sensory, and receptive language tasks was determined by evaluating the power of the high gamma frequency band (60-170 Hz). The sensitivity and specificity of RTFM were tested against ESM and fMRI results. "Next-neighbor" approach demonstrated [sensitivity/specificity %] (1) RTFM against ESM: 100.00/79.70 for hand motor; 100.00/73.87 for hand sensory; -/87 for language (it was not identified by the ESM); (2) RTFM against fMRI: 100.00/84.4 for hand motor; 66.70/85.35 for hand sensory; and 87.85/77.70 for language. The results of the quantitative "next-neighbor" RTFM evaluation were concordant to those from ESM and fMRI. The RTFM correlates well with localization of hand motor function provided by ESM and fMRI, which may offer added localization in the operating room and guidance for extraoperative ESM mapping. Real-time functional mapping correlates with fMRI language activation when ESM findings are negative. It has fewer limitations than ESM and greater flexibility in activation paradigms and measuring responses.

Real-time cytometric assay of nitric oxide and superoxide interaction in peripheral blood monocytes: A no-wash, no-lyse kinetic method.

PubMed

Balaguer, Susana; Diaz, Laura; Gomes, Angela; Herrera, Guadalupe; O'Connor, José-Enrique; Urios, Amparo; Felipo, Vicente; Montoliu, Carmina

2017-05-01

Nitric oxide (NO) and its related reactive nitrogen species (RNS) and reactive oxygen species (ROS) are crucial in monocyte responses against pathogens and also in inflammatory conditions. Central to both processes is the generation of the strong oxidant peroxynitrite (ONOO) by a fast reaction between NO and superoxide anion. ONOO is a biochemical junction for ROS- and RNS cytotoxicity and causes protein nitrosylation. Circulating by-products of protein nitrosylation are early biomarkers of inflammation-based conditions, including minimal hepatic encephalopathy in cirrhotic patients (Montoliu et al., Am J Gastroenterol 2011; 106:1629-1637). In this context, we have designed a novel no-wash, no-lyse real-time flow cytometry assay to detect and follow-up the NO- and superoxide-driven generation of ONOO in peripheral blood monocytes. Whole blood samples were stained with CD45 and CD14 antibodies plus one of a series of fluorescent probes sensitive to RNS, ROS, or glutathione, namely 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate, dihydrorhodamine 123, MitoSOX Red, dihydroethidium, and 5-chloromethylfluorescein diacetate. Samples were exposed sequentially to a NO donor and three different superoxide donors, and analyzed in real time by kinetic flow cytometry. Relevant kinetic descriptors, such as the rate of fluorescence change, were calculated from the kinetic plot. The generation of ONOO, which consumes both NO and superoxide, led to a decrease in the intensity of the cellular fluorescence of the probes sensitive to these molecules. This is a fast and simple assay that may be used to monitor the intracellular generation of ONOO in physiological, pathological, and pharmacological contexts. © 2015 International Clinical Cytometry Society. © 2015 International Clinical Cytometry Society.

Real-time polarization-sensitive optical coherence tomography data processing with parallel computing

PubMed Central

Liu, Gangjun; Zhang, Jun; Yu, Lingfeng; Xie, Tuqiang; Chen, Zhongping

2010-01-01

With the increase of the A-line speed of optical coherence tomography (OCT) systems, real-time processing of acquired data has become a bottleneck. The shared-memory parallel computing technique is used to process OCT data in real time. The real-time processing power of a quad-core personal computer (PC) is analyzed. It is shown that the quad-core PC could provide real-time OCT data processing ability of more than 80K A-lines per second. A real-time, fiber-based, swept source polarization-sensitive OCT system with 20K A-line speed is demonstrated with this technique. The real-time 2D and 3D polarization-sensitive imaging of chicken muscle and pig tendon is also demonstrated. PMID:19904337

A Pro-active Real-time Forecasting and Decision Support System for Daily Management of Marine Works

NASA Astrophysics Data System (ADS)

Bollen, Mark; Leyssen, Gert; Smets, Steven; De Wachter, Tom

2016-04-01

Marine Works involving turbidity generating activities (eg. dredging, dredge spoil placement) can generate environmental stress in and around a project area in the form of sediment plumes causing light reduction and sedimentation. If these works are situated near sensitive habitats like sea-grass beds, coral reefs or sensitive human activities eg. aquaculture farms or water intakes, or if contaminants are present in the water soil environmental scrutiny is advised. Environmental Regulations can impose limitations to these activities in the form of turbidity thresholds, spill budgets, contaminant levels. Breaching environmental regulations can result in increased monitoring, adaptation of the works planning and production rates and ultimately in a (temporary) stop of activities all of which entail time and cost impacts for a contractor and/or client. Sediment plume behaviour is governed by the dredging process, soil properties and ambient conditions (currents, water depth) and can be modelled. Usually this is done during the preparatory EIA phase of a project, for estimation of environmental impact based on climatic scenarios. An operational forecasting tool is developed to adapt marine work schedules to the real-time circumstances and thus evade exceedance of critical threshold levels at sensitive areas. The forecasting system is based on a Python-based workflow manager with a MySQL database and a Django frontend web tool for user interaction and visualisation of the model results. The core consists of a numerical hydrodynamic model with sediment transport module (Mike21 from DHI). This model is driven by space and time varying wind fields and wave boundary conditions, and turbidity inputs (suspended sediment source terms) based on marine works production rates and soil properties. The resulting threshold analysis allows the operator to indicate potential impact at the sensitive areas and instigate an adaption of the marine work schedule if needed. In order to use this toolbox in real-time situations and facilitate forecasting of impacts of planned dredge works, the following operational online functionalities are implemented: • Automated fetch and preparation of the input data, including 7 day forecast wind and wave fields and real-time measurements, and user defined the turbidity inputs based on scheduled marine works. • Generate automated forecasts and running user configurable scenarios at the same time in parallel. • Export and convert the model results, time series and maps, into a standardized format (netcdf). • Automatic analysis and processing of model results, including the calculation of indicator turbidity values and the exceedance analysis of threshold levels at the different sensitive areas. Data assimilation with the real time on site turbidity measurements is implemented in this threshold analysis. • Pre-programmed generation of animated sediment plumes, specific charts and pdf reports to allow a rapid interpretation of the model results by the operators and facilitating decision making in the operational planning. The performed marine works, resulting from the marine work schedule proposed by the forecasting system, are evaluated by a threshold analysis on the validated turbidity measurements on the sensitive sites. This machine learning loop allows a check of the system in order to evaluate forecast and model uncertainties.

Label-free thioflavin T/G-quadruplex-based real-time strand displacement amplification for biosensing applications.

PubMed

Du, Yi-Chen; Zhu, Li-Na; Kong, De-Ming

2016-12-15

To promote application of strand-displacement amplification (SDA) techniques in biosensing, a label-free, real-time monitoring strategy for isothermal nucleic acid amplification reactions was designed. G-quadruplex structures were introduced into SDA products using specific recognition of G-quadruplexes by the fluorogenic dye thioflavin T. Performance was good for real-time monitoring of traditional SDA by a linear-amplification mechanism and for exponential cross-triggered SDA amplification. The strategy worked on a commercial real-time PCR instrument, making it suitable for biosensing platforms. As examples, two highly sensitive and specific biosensors were designed for analysis of the activity of uracil-DNA glycosylase (UDG) and the restriction endonuclease EcoRI. Detection limits were 6×10(-5)U/mL for UDG and 0.016U/mL for EcoRI. Detection of corresponding targets in complex matrices such as cell lysates or human serum was also demonstrated. Compared to traditional end-point detection methods, real-time SDA-based approaches have the advantages of simple, fast operation; high sensitivity; low risk of carryover contamination; and very high throughput. The introduction of real-time monitoring strategies may promote application of SDA reactions in biosensor design. Copyright © 2016 Elsevier B.V. All rights reserved.

Towards Smart Homes Using Low Level Sensory Data

PubMed Central

Khattak, Asad Masood; Truc, Phan Tran Ho; Hung, Le Xuan; Vinh, La The; Dang, Viet-Hung; Guan, Donghai; Pervez, Zeeshan; Han, Manhyung; Lee, Sungyoung; Lee, Young-Koo

2011-01-01

Ubiquitous Life Care (u-Life care) is receiving attention because it provides high quality and low cost care services. To provide spontaneous and robust healthcare services, knowledge of a patient’s real-time daily life activities is required. Context information with real-time daily life activities can help to provide better services and to improve healthcare delivery. The performance and accuracy of existing life care systems is not reliable, even with a limited number of services. This paper presents a Human Activity Recognition Engine (HARE) that monitors human health as well as activities using heterogeneous sensor technology and processes these activities intelligently on a Cloud platform for providing improved care at low cost. We focus on activity recognition using video-based, wearable sensor-based, and location-based activity recognition engines and then use intelligent processing to analyze the context of the activities performed. The experimental results of all the components showed good accuracy against existing techniques. The system is deployed on Cloud for Alzheimer’s disease patients (as a case study) with four activity recognition engines to identify low level activity from the raw data captured by sensors. These are then manipulated using ontology to infer higher level activities and make decisions about a patient’s activity using patient profile information and customized rules. PMID:22247682

Real-time PCR assay for the detection and quantification of Legionella pneumophila in environmental water samples: utility for daily practice.

PubMed

Morio, Florent; Corvec, Stéphane; Caroff, Nathalie; Le Gallou, Florence; Drugeon, Henri; Reynaud, Alain

2008-07-01

We developed a quantitative real-time PCR assay targeting the mip gene of Legionella pneumophila for a prospective study from September 2004 to April 2005. It was compared with a standard culture method (French guideline AFNOR T90-431), analysing 120 water samples collected to monitor the risk related to Legionellae at Nantes hospital and to investigate a case of legionellosis acquired from hospital environment. Samples from six distinct water distribution systems were analysed by DNA extraction, amplification and detection with specific primers and FRET probes. The detection limit was 100 genomic units of L. pneumophila per liter (GU/l), the positivity threshold about 600 GU/l and the quantification limit 800 GU/l. PCR results were divided into three groups: negative (n=63), positive but non-quantifiable (n=22) or positive (n=35). PCR showed higher sensitivity than culture, whereas four culture-positive samples appeared negative by PCR (PCR inhibitor detected for two of them). Although no correlation was observed between both methods and real-time PCR cannot substitute for the reference method, it represents an interesting complement. Its sensitivity, reproducibility and rapidity appear particularly interesting in epidemic contexts in order to identify the source of contamination or to evaluate critical points of contamination in water distribution systems.

Incorporating Real-time Earthquake Information into Large Enrollment Natural Disaster Course Learning

NASA Astrophysics Data System (ADS)

Furlong, K. P.; Benz, H.; Hayes, G. P.; Villasenor, A.

2010-12-01

Although most would agree that the occurrence of natural disaster events such as earthquakes, volcanic eruptions, and floods can provide effective learning opportunities for natural hazards-based courses, implementing compelling materials into the large-enrollment classroom environment can be difficult. These natural hazard events derive much of their learning potential from their real-time nature, and in the modern 24/7 news-cycle where all but the most devastating events are quickly out of the public eye, the shelf life for an event is quite limited. To maximize the learning potential of these events requires that both authoritative information be available and course materials be generated as the event unfolds. Although many events such as hurricanes, flooding, and volcanic eruptions provide some precursory warnings, and thus one can prepare background materials to place the main event into context, earthquakes present a particularly confounding situation of providing no warning, but where context is critical to student learning. Attempting to implement real-time materials into large enrollment classes faces the additional hindrance of limited internet access (for students) in most lecture classrooms. In Earth 101 Natural Disasters: Hollywood vs Reality, taught as a large enrollment (150+ students) general education course at Penn State, we are collaborating with the USGS’s National Earthquake Information Center (NEIC) to develop efficient means to incorporate their real-time products into learning activities in the lecture hall environment. Over time (and numerous events) we have developed a template for presenting USGS-produced real-time information in lecture mode. The event-specific materials can be quickly incorporated and updated, along with key contextual materials, to provide students with up-to-the-minute current information. In addition, we have also developed in-class activities, such as student determination of population exposure to severe ground shaking (i.e. simulating the USGS PAGER product), tsunami warning calculations, and building damage analyses that allow the students to participate in realistic hazard analyses as the event unfolds. Examples of these templates and activities will be presented. Key to the successful implementation of real-time materials is sufficient flexibility and adaptability in the course syllabus.

NAIMA as a solution for future GMO diagnostics challenges.

PubMed

Dobnik, David; Morisset, Dany; Gruden, Kristina

2010-03-01

In the field of genetically modified organism (GMO) diagnostics, real-time PCR has been the method of choice for target detection and quantification in most laboratories. Despite its numerous advantages, however, the lack of a true multiplexing option may render real-time PCR less practical in the face of future GMO detection challenges such as the multiplicity and increasing complexity of new transgenic events, as well as the repeated occurrence of unauthorized GMOs on the market. In this context, we recently reported the development of a novel multiplex quantitative DNA-based target amplification method, named NASBA implemented microarray analysis (NAIMA), which is suitable for sensitive, specific and quantitative detection of GMOs on a microarray. In this article, the performance of NAIMA is compared with that of real-time PCR, the focus being their performances in view of the upcoming challenge to detect/quantify an increasing number of possible GMOs at a sustainable cost and affordable staff effort. Finally, we present our conclusions concerning the applicability of NAIMA for future use in GMO diagnostics.

Embedded Triboelectric Active Sensors for Real-Time Pneumatic Monitoring.

PubMed

Fu, Xian Peng; Bu, Tian Zhao; Xi, Feng Ben; Cheng, Ting Hai; Zhang, Chi; Wang, Zhong Lin

2017-09-20

Pneumatic monitoring sensors have great demands for power supply in cylinder systems. Here, we present an embedded sliding triboelectric nanogenerator (TENG) in air cylinder as active sensors for position and velocity monitoring. The embedded TENG is composed of a circular poly(tetrafluoroethylene) polymer and a triangular copper electrode. The working mechanism as triboelectric active sensors and electric output performance are systematically investigated. By integrating into the pneumatic system, the embedded triboelectric active sensors have been used for real-time air pressure/flow monitoring and energy storage. Air pressures are measured from 0.04 to 0.12 MPa at a step of 0.02 MPa with a sensitivity of 49.235 V/MPa, as well as airflow from 50 to 250 L/min at a step of 50 L/min with a sensitivity of 0.002 μA·min/L. This work has first demonstrated triboelectric active sensors for pneumatic monitoring and may promote the development of TENG in intelligent pneumatic system.

Exploring Marine Ecosystems with Elementary School Portuguese Children: Inquiry-Based Project Activities Focused on "Real-Life" Contexts

ERIC Educational Resources Information Center

Guilherme, Elsa; Faria, Cláudia; Boaventura, Diana

2016-01-01

The purpose of the study was to investigate how young students engage in an inquiry-based project driven by real-life contexts. Elementary school children were engaged in a small inquiry project centred on marine biodiversity and species adaptations. All activities included the exploration of an out-of-school setting as a learning context. A total…

Real-time tricolor phase measuring profilometry based on CCD sensitivity calibration

NASA Astrophysics Data System (ADS)

Zhu, Lin; Cao, Yiping; He, Dawu; Chen, Cheng

2017-02-01

A real-time tricolor phase measuring profilometry (RTPMP) based on charge coupled device (CCD) sensitivity calibration is proposed. Only one colour fringe pattern whose red (R), green (G) and blue (B) components are, respectively, coded as three sinusoidal phase-shifting gratings with an equivalent shifting phase of 2π/3 is needed and sent to an appointed flash memory on a specialized digital light projector (SDLP). A specialized time-division multiplexing timing sequence actively controls the SDLP to project the fringe patterns in R, G and B channels sequentially onto the measured object in one over seventy-two of a second and meanwhile actively controls a high frame rate monochrome CCD camera to capture the corresponding deformed patterns synchronously with the SDLP. So the sufficient information for reconstructing the three-dimensional (3D) shape in one over twenty-four of a second is obtained. Due to the different spectral sensitivity of the CCD camera to RGB lights, the captured deformed patterns from R, G and B channels cannot share the same peak and valley, which will lead to lower accuracy or even failing to reconstruct the 3D shape. So a deformed pattern amending method based on CCD sensitivity calibration is developed to guarantee the accurate 3D reconstruction. The experimental results verify the feasibility of the proposed RTPMP method. The proposed RTPMP method can obtain the 3D shape at over the video frame rate of 24 frames per second, avoid the colour crosstalk completely and be effective for measuring real-time changing object.

Ultrafast, sensitive and large-volume on-chip real-time PCR for the molecular diagnosis of bacterial and viral infections.

PubMed

Houssin, Timothée; Cramer, Jérémy; Grojsman, Rébecca; Bellahsene, Lyes; Colas, Guillaume; Moulet, Hélène; Minnella, Walter; Pannetier, Christophe; Leberre, Maël; Plecis, Adrien; Chen, Yong

2016-04-21

To control future infectious disease outbreaks, like the 2014 Ebola epidemic, it is necessary to develop ultrafast molecular assays enabling rapid and sensitive diagnoses. To that end, several ultrafast real-time PCR systems have been previously developed, but they present issues that hinder their wide adoption, notably regarding their sensitivity and detection volume. An ultrafast, sensitive and large-volume real-time PCR system based on microfluidic thermalization is presented herein. The method is based on the circulation of pre-heated liquids in a microfluidic chip that thermalize the PCR chamber by diffusion and ultrafast flow switches. The system can achieve up to 30 real-time PCR cycles in around 2 minutes, which makes it the fastest PCR thermalization system for regular sample volume to the best of our knowledge. After biochemical optimization, anthrax and Ebola simulating agents could be respectively detected by a real-time PCR in 7 minutes and a reverse transcription real-time PCR in 7.5 minutes. These detections are respectively 6.4 and 7.2 times faster than with an off-the-shelf apparatus, while conserving real-time PCR sample volume, efficiency, selectivity and sensitivity. The high-speed thermalization also enabled us to perform sharp melting curve analyses in only 20 s and to discriminate amplicons of different lengths by rapid real-time PCR. This real-time PCR microfluidic thermalization system is cost-effective, versatile and can be then further developed for point-of-care, multiplexed, ultrafast and highly sensitive molecular diagnoses of bacterial and viral diseases.

Understanding the physical and social contexts of children's nonschool sedentary behavior: an ecological momentary assessment study.

PubMed

Liao, Yue; Intille, Stephen; Wolch, Jennifer; Pentz, Mary Ann; Dunton, Genevieve Fridlund

2014-03-01

Research on children's sedentary behavior has relied on recall-based self-report or accelerometer methods, which do not assess the context of such behavior. This study used ecological momentary assessment (EMA) to determine where and with whom children's sedentary behavior occurs during their nonschool time. Children (N = 120) ages 9-13 years (51% male, 33% Hispanic) wore mobile phones that prompted surveys (20 total) for 4 days. Surveys measured current activity (eg, exercise, watching TV), physical location (eg, home, outdoors), and social company (eg, family, friends). Children engaged in a greater percentage of leisure-oriented (eg, watching TV) than productive (eg, reading, doing homework) sedentary behavior (70% vs 30%, respectively). Most of children's sedentary activity occurred at home (85%). Children's sedentary activity took place most often with family members (58%). Differences in physical context of sedentary behavior were found for older vs. younger children (P < .05). Type of sedentary behavior differed by gender, racial/ethnic group, and social context (P < .05). Children may prefer or have greater opportunities to be sedentary in some contexts than others. Research demonstrates the potential for using EMA to capture real-time information about children's sedentary behavior during their nonschool time.

Stretchable and Photocatalytically Renewable Electrochemical Sensor Based on Sandwich Nanonetworks for Real-Time Monitoring of Cells.

PubMed

Wang, Ya-Wen; Liu, Yan-Ling; Xu, Jia-Quan; Qin, Yu; Huang, Wei-Hua

2018-05-15

Stretchable electrochemical (EC) sensors have broad prospects in real-time monitoring of living cells and tissues owing to their excellent elasticity and deformability. However, the redox reaction products and cell secretions are easily adsorbed on the electrode, resulting in sensor fouling and passivation. Herein, we developed a stretchable and photocatalytically renewable EC sensor based on Au nanotubes (NTs) and TiO 2 nanowires (NWs) sandwich nanonetworks. The external Au NTs are used for EC sensing, and internal TiO 2 NWs provide photocatalytic performance to degrade contaminants, which endows the sensor with excellent EC performance, high photocatalytic activity, and favorable mechanical tensile property. This allows highly sensitive recycling monitoring of NO released from endothelial cells and 5-HT released from mast cells under their stretching states in real time, therefore providing a promising tool to unravel elastic and mechanically sensitive cells, tissues, and organs.

Physicochemical stability and biological activity of Withania somnifera extract under real-time and accelerated storage conditions.

PubMed

Patil, Dada; Gautam, Manish; Jadhav, Umesh; Mishra, Sanjay; Karupothula, Suresh; Gairola, Sunil; Jadhav, Suresh; Patwardhan, Bhushan

2010-03-01

Stability testing at preformulation stages is a crucial part of drug development. We studied physicochemical stability and biological activity of Withania somnifera (ashwagandha) dried root aqueous extract during six months real-time and under accelerated storage conditions. The characteristic constituents of ashwagandha roots include withanolides such as withaferin A and withanolide A. We modified and validated the HPLC-DAD method for quantitative measurement of withanolides and fingerprint analysis. The results suggest a significant decline in withaferin A and withanolide A content under real and accelerated conditions. The HPLC fingerprint analysis showed significant changes in some peaks during real and accelerated storage (> 20 %). We also observed incidences of clump formation and moisture sensitivity (> 10 %) under real-time and accelerated storage conditions. These changes were concurrent with a significant decline in immunomodulatory activity (p < 0.01) during the third month of the accelerated storage. Thus, adequate control of temperature and humidity is important for WSE containing formulations. This study may help in proposing suitable guidance for storage conditions and shelf life of ashwagandha formulations. (c) Georg Thieme Verlag KG Stuttgart . New York.

Expanding our perspectives on research in musculoskeletal science and practice.

PubMed

Kerry, Roger

2017-12-01

The quantity and quality of scientific research within physiotherapy has unquestionably grown and matured over the last few decades, especially since the "formal" onset of evidence-based physiotherapy in the 1990s. The urgent need to evaluate our practice for effectiveness and efficiency has been responded to with thought and respect to both scientific integrity and shop-floor clinical needs. However, after thirty years or more of a professionally-governed and strategic approach to research activity, it is now timely to reflect, review, and consider the next chapter in the relationship between scientific research and clinical practice. This masterclass aims to develop a research vision for the future of physiotherapy. It is proposed that a crisis is evident within evidence-based physiotherapy, particular so given the assumed complexity and context-sensitivity of our clinical practice. This crisis period has highlighted fundamental limitations within the way research and practice are currently related. These limitations are presented and framed within the problematisation of empirical and philosophical concerns. As research becomes increasingly aligned to traditional scientific principles, examination of the real world context in which its outcomes are intended expose critical challenges for both research and clinical practice. A reconceptualisation of fundamental elements of scientific research may allow more meaningful relationships between research and clinical practice. A proposed research vision encourages scientific activity to embrace real-world complexity in a way that it is presently unable to. An enhanced person-centered, scientifically-informed world of effective musculoskeletal practice is envisaged. Copyright © 2017 Elsevier Ltd. All rights reserved.

The smartphone brain scanner: a portable real-time neuroimaging system.

PubMed

Stopczynski, Arkadiusz; Stahlhut, Carsten; Larsen, Jakob Eg; Petersen, Michael Kai; Hansen, Lars Kai

2014-01-01

Combining low-cost wireless EEG sensors with smartphones offers novel opportunities for mobile brain imaging in an everyday context. Here we present the technical details and validation of a framework for building multi-platform, portable EEG applications with real-time 3D source reconstruction. The system--Smartphone Brain Scanner--combines an off-the-shelf neuroheadset or EEG cap with a smartphone or tablet, and as such represents the first fully portable system for real-time 3D EEG imaging. We discuss the benefits and challenges, including technical limitations as well as details of real-time reconstruction of 3D images of brain activity. We present examples of brain activity captured in a simple experiment involving imagined finger tapping, which shows that the acquired signal in a relevant brain region is similar to that obtained with standard EEG lab equipment. Although the quality of the signal in a mobile solution using an off-the-shelf consumer neuroheadset is lower than the signal obtained using high-density standard EEG equipment, we propose mobile application development may offset the disadvantages and provide completely new opportunities for neuroimaging in natural settings.

Detection of tumor markers in prostate cancer and comparison of sensitivity between real time and nested PCR.

PubMed

Matsuoka, Takayuki; Shigemura, Katsumi; Yamamichi, Fukashi; Fujisawa, Masato; Kawabata, Masato; Shirakawa, Toshiro

2012-06-27

The objective of this study is to investigate and compare the sensitivity in conventional PCR, quantitative real time PCR, nested PCR and western blots for detection of prostate cancer tumor markers using prostate cancer (PCa) cells. We performed conventional PCR, quantitative real time PCR, nested PCR, and western blots using 5 kinds of PCa cells. Prostate specific antigen (PSA), prostate specific membrane antigen (PSMA), and androgen receptor (AR) were compared for their detection sensitivity by real time PCR and nested PCR. In real time PCR, there was a significant correlation between cell number and the RNA concentration obtained (R(2)=0.9944) for PSA, PSMA, and AR. We found it possible to detect these markers from a single LNCaP cell in both real time and nested PCR. By comparison, nested PCR reached a linear curve in fewer PCR cycles than real time PCR, suggesting that nested PCR may offer PCR results more quickly than real time PCR. In conclusion, nested PCR may offer tumor maker detection in PCa cells more quickly (with fewer PCR cycles) with the same high sensitivity as real time PCR. Further study is necessary to establish and evaluate the best tool for PCa tumor marker detection.

SAPIENS: Spreading Activation Processor for Information Encoded in Network Structures. Technical Report No. 296.

ERIC Educational Resources Information Center

Ortony, Andrew; Radin, Dean I.

The product of researchers' efforts to develop a computer processor which distinguishes between relevant and irrelevant information in the database, Spreading Activation Processor for Information Encoded in Network Structures (SAPIENS) exhibits (1) context sensitivity, (2) efficiency, (3) decreasing activation over time, (4) summation of…

Tailored motivational message generation: A model and practical framework for real-time physical activity coaching.

PubMed

Op den Akker, Harm; Cabrita, Miriam; Op den Akker, Rieks; Jones, Valerie M; Hermens, Hermie J

2015-06-01

This paper presents a comprehensive and practical framework for automatic generation of real-time tailored messages in behavior change applications. Basic aspects of motivational messages are time, intention, content and presentation. Tailoring of messages to the individual user may involve all aspects of communication. A linear modular system is presented for generating such messages. It is explained how properties of user and context are taken into account in each of the modules of the system and how they affect the linguistic presentation of the generated messages. The model of motivational messages presented is based on an analysis of existing literature as well as the analysis of a corpus of motivational messages used in previous studies. The model extends existing 'ontology-based' approaches to message generation for real-time coaching systems found in the literature. Practical examples are given on how simple tailoring rules can be implemented throughout the various stages of the framework. Such examples can guide further research by clarifying what it means to use e.g. user targeting to tailor a message. As primary example we look at the issue of promoting daily physical activity. Future work is pointed out in applying the present model and framework, defining efficient ways of evaluating individual tailoring components, and improving effectiveness through the creation of accurate and complete user- and context models. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparison of viable plate count, turbidity measurement and real-time PCR for quantification of Porphyromonas gingivalis.

PubMed

Clais, S; Boulet, G; Van Kerckhoven, M; Lanckacker, E; Delputte, P; Maes, L; Cos, P

2015-01-01

The viable plate count (VPC) is considered as the reference method for bacterial enumeration in periodontal microbiology but shows some important limitations for anaerobic bacteria. As anaerobes such as Porphyromonas gingivalis are difficult to culture, VPC becomes time-consuming and less sensitive. Hence, efficient normalization of experimental data to bacterial cell count requires alternative rapid and reliable quantification methods. This study compared the performance of VPC with that of turbidity measurement and real-time PCR (qPCR) in an experimental context using highly concentrated bacterial suspensions. Our TaqMan-based qPCR assay for P. gingivalis 16S rRNA proved to be sensitive and specific. Turbidity measurements offer a fast method to assess P. gingivalis growth, but suffer from high variability and a limited dynamic range. VPC was very time-consuming and less repeatable than qPCR. Our study concludes that qPCR provides the most rapid and precise approach for P. gingivalis quantification. Although our data were gathered in a specific research context, we believe that our conclusions on the inferior performance of VPC and turbidity measurements in comparison to qPCR can be extended to other research and clinical settings and even to other difficult-to-culture micro-organisms. Various clinical and research settings require fast and reliable quantification of bacterial suspensions. The viable plate count method (VPC) is generally seen as 'the gold standard' for bacterial enumeration. However, VPC-based quantification of anaerobes such as Porphyromonas gingivalis is time-consuming due to their stringent growth requirements and shows poor repeatability. Comparison of VPC, turbidity measurement and TaqMan-based qPCR demonstrated that qPCR possesses important advantages regarding speed, accuracy and repeatability. © 2014 The Society for Applied Microbiology.

Computing moment to moment BOLD activation for real-time neurofeedback

PubMed Central

Hinds, Oliver; Ghosh, Satrajit; Thompson, Todd W.; Yoo, Julie J.; Whitfield-Gabrieli, Susan; Triantafyllou, Christina; Gabrieli, John D.E.

2013-01-01

Estimating moment to moment changes in blood oxygenation level dependent (BOLD) activation levels from functional magnetic resonance imaging (fMRI) data has applications for learned regulation of regional activation, brain state monitoring, and brain-machine interfaces. In each of these contexts, accurate estimation of the BOLD signal in as little time as possible is desired. This is a challenging problem due to the low signal-to-noise ratio of fMRI data. Previous methods for real-time fMRI analysis have either sacrificed the ability to compute moment to moment activation changes by averaging several acquisitions into a single activation estimate or have sacrificed accuracy by failing to account for prominent sources of noise in the fMRI signal. Here we present a new method for computing the amount of activation present in a single fMRI acquisition that separates moment to moment changes in the fMRI signal intensity attributable to neural sources from those due to noise, resulting in a feedback signal more reflective of neural activation. This method computes an incremental general linear model fit to the fMRI timeseries, which is used to calculate the expected signal intensity at each new acquisition. The difference between the measured intensity and the expected intensity is scaled by the variance of the estimator in order to transform this residual difference into a statistic. Both synthetic and real data were used to validate this method and compare it to the only other published real-time fMRI method. PMID:20682350

10-Month-Old Infants Are Sensitive to the Time Course of Perceived Actions: Eye-Tracking and EEG Evidence.

PubMed

Bache, Cathleen; Springer, Anne; Noack, Hannes; Stadler, Waltraud; Kopp, Franziska; Lindenberger, Ulman; Werkle-Bergner, Markus

2017-01-01

Research has shown that infants are able to track a moving target efficiently - even if it is transiently occluded from sight. This basic ability allows prediction of when and where events happen in everyday life. Yet, it is unclear whether, and how, infants internally represent the time course of ongoing movements to derive predictions. In this study, 10-month-old crawlers observed the video of a same-aged crawling baby that was transiently occluded and reappeared in either a temporally continuous or non-continuous manner (i.e., delayed by 500 ms vs. forwarded by 500 ms relative to the real-time movement). Eye movement and rhythmic neural brain activity (EEG) were measured simultaneously. Eye movement analyses showed that infants were sensitive to slight temporal shifts in movement continuation after occlusion. Furthermore, brain activity associated with sensorimotor processing differed between observation of continuous and non-continuous movements. Early sensitivity to an action's timing may hence be explained within the internal real-time simulation account of action observation. Overall, the results support the hypothesis that 10-month-old infants are well prepared for internal representation of the time course of observed movements that are within the infants' current motor repertoire.

10-Month-Old Infants Are Sensitive to the Time Course of Perceived Actions: Eye-Tracking and EEG Evidence

PubMed Central

Bache, Cathleen; Springer, Anne; Noack, Hannes; Stadler, Waltraud; Kopp, Franziska; Lindenberger, Ulman; Werkle-Bergner, Markus

2017-01-01

Research has shown that infants are able to track a moving target efficiently – even if it is transiently occluded from sight. This basic ability allows prediction of when and where events happen in everyday life. Yet, it is unclear whether, and how, infants internally represent the time course of ongoing movements to derive predictions. In this study, 10-month-old crawlers observed the video of a same-aged crawling baby that was transiently occluded and reappeared in either a temporally continuous or non-continuous manner (i.e., delayed by 500 ms vs. forwarded by 500 ms relative to the real-time movement). Eye movement and rhythmic neural brain activity (EEG) were measured simultaneously. Eye movement analyses showed that infants were sensitive to slight temporal shifts in movement continuation after occlusion. Furthermore, brain activity associated with sensorimotor processing differed between observation of continuous and non-continuous movements. Early sensitivity to an action’s timing may hence be explained within the internal real-time simulation account of action observation. Overall, the results support the hypothesis that 10-month-old infants are well prepared for internal representation of the time course of observed movements that are within the infants’ current motor repertoire. PMID:28769831

Competition in the Brain. The Contribution of EEG and fNIRS Modulation and Personality Effects in Social Ranking.

PubMed

Balconi, Michela; Vanutelli, Maria E

2016-01-01

In the present study, the social ranking perception in competition was explored. Brain response (alpha band oscillations, EEG; hemodynamic activity, O2Hb), as well as self-perception of social ranking, cognitive performance, and personality trait (Behavioral Activation System, BAS) were considered during a competitive joint-action. Subjects were required to develop a strategy to obtain a better outcome than a competitor (C) (in term of error rate, and response time, RT). A pre-feedback (without a specific feedback on the performance) and a post-feedback condition (which reinforced the improved performance) were provided. It was found that higher-BAS participants responded in greater measure to perceived higher cognitive performance (post-feedback condition), with increased left prefrontal activity, higher ranking perception, and a better real performance (reduced RTs). These results were explained in term of increased sense of self-efficacy and social position, probably based on higher-BAS sensitivity to reinforcing conditions. In addition, the hemispheric effect in favor of the left side characterized the competitive behavior, showing an imbalance for high-BAS in comparison to low-BAS in the case of a rewarding (post-feedback) context. Therefore, the present results confirmed the significance of BAS in modulating brain responsiveness, self-perceived social position, and real performance during an interpersonal competitive action which is considered highly relevant for social status.

Physical and social contextual influences on children's leisure-time physical activity: an ecological momentary assessment study.

PubMed

Dunton, Genevieve F; Liao, Yue; Intille, Stephen; Wolch, Jennifer; Pentz, Mary Ann

2011-01-01

This study used real-time electronic surveys delivered through mobile phones, known as Ecological Momentary Assessment (EMA), to determine whether level and experience of leisure-time physical activity differ across children's physical and social contexts. Children (N = 121; ages 9 to 13 years; 52% male, 32% Hispanic/Latino) participated in 4 days (Fri.-Mon.) of EMA during nonschool time. Electronic surveys (20 total) assessed primary activity (eg, active play/sports/exercise), physical location (eg, home, outdoors), social context (eg, friends, alone), current mood (positive and negative affect), and enjoyment. Responses were time-matched to the number of steps and minutes of moderate-to-vigorous physical activity (MVPA; measured by accelerometer) in the 30 minutes before each survey. Mean steps and MVPA were greater outdoors than at home or at someone else's house (all P < .05). Steps were greater with multiple categories of company (eg, friends and family together) than with family members only or alone (all P < .05). Enjoyment was greater outdoors than at home or someone else's house (all P < .05). Negative affect was greater when alone and with family only than friends only (all P < .05). Results describing the value of outdoor and social settings could inform context-specific interventions in this age group.

The COGs (context, object, and goals) in multisensory processing.

PubMed

ten Oever, Sanne; Romei, Vincenzo; van Atteveldt, Nienke; Soto-Faraco, Salvador; Murray, Micah M; Matusz, Pawel J

2016-05-01

Our understanding of how perception operates in real-world environments has been substantially advanced by studying both multisensory processes and "top-down" control processes influencing sensory processing via activity from higher-order brain areas, such as attention, memory, and expectations. As the two topics have been traditionally studied separately, the mechanisms orchestrating real-world multisensory processing remain unclear. Past work has revealed that the observer's goals gate the influence of many multisensory processes on brain and behavioural responses, whereas some other multisensory processes might occur independently of these goals. Consequently, other forms of top-down control beyond goal dependence are necessary to explain the full range of multisensory effects currently reported at the brain and the cognitive level. These forms of control include sensitivity to stimulus context as well as the detection of matches (or lack thereof) between a multisensory stimulus and categorical attributes of naturalistic objects (e.g. tools, animals). In this review we discuss and integrate the existing findings that demonstrate the importance of such goal-, object- and context-based top-down control over multisensory processing. We then put forward a few principles emerging from this literature review with respect to the mechanisms underlying multisensory processing and discuss their possible broader implications.

Subjective sleepiness is a sensitive indicator of insufficient sleep and impaired waking function.

PubMed

Akerstedt, Torbjörn; Anund, Anna; Axelsson, John; Kecklund, Göran

2014-06-01

The main consequence of insufficient sleep is sleepiness. While measures of sleep latency, continuous encephalographical/electro-oculographical (EEG/EOG) recording and performance tests are useful indicators of sleepiness in the laboratory and clinic, they are not easily implemented in large, real-life field studies. Subjective ratings of sleepiness, which are easily applied and unobtrusive, are an alternative, but whether they measure sleepiness sensitively, reliably and validly remains uncertain. This review brings together research relevant to these issues. It is focused on the Karolinska Sleepiness Scale (KSS), which is a nine-point Likert-type scale. The diurnal pattern of sleepiness is U-shaped, with high KSS values in the morning and late evening, and with great stability across years. KSS values increase sensitively during acute total and repeated partial sleep deprivation and night work, including night driving. The effect sizes range between 1.5 and 3. The relation to driving performance or EEG/EOG indicators of sleepiness is highly significant, strongly curvilinear and consistent across individuals. High (>6) KSS values are associated particularly with impaired driving performance and sleep intrusions in the EEG. KSS values are also increased in many clinical conditions such as sleep apnea, depression and burnout. The context has a strong influence on KSS ratings. Thus, physical activity, social interaction and light exposure will reduce KSS values by 1-2 units. In contrast, time-on-task in a monotonous context will increase KSS values by 1-2 units. In summary, subjective ratings of sleepiness as described here is as sensitive and valid an indicator of sleepiness as objective measures, and particularly suitable for field studies. © 2014 European Sleep Research Society.

Development of an on-site rapid real-time polymerase chain reaction system and the characterization of suitable DNA polymerases for TaqMan probe technology.

PubMed

Furutani, Shunsuke; Naruishi, Nahoko; Hagihara, Yoshihisa; Nagai, Hidenori

2016-08-01

On-site quantitative analyses of microorganisms (including viruses) by the polymerase chain reaction (PCR) system are significantly influencing medical and biological research. We have developed a remarkably rapid and portable real-time PCR system that is based on microfluidic approaches. Real-time PCR using TaqMan probes consists of a complex reaction. Therefore, in a rapid real-time PCR, the optimum DNA polymerase must be estimated by using actual real-time PCR conditions. In this study, we compared the performance of three DNA polymerases in actual PCR conditions using our rapid real-time PCR system. Although KAPA2G Fast HS DNA Polymerase has the highest enzymatic activity among them, SpeedSTAR HS DNA Polymerase exhibited better performance to rapidly increase the fluorescence signal in an actual real-time PCR using TaqMan probes. Furthermore, we achieved rapid detection of Escherichia coli in 7 min by using SpeedSTAR HS DNA Polymerase with the same sensitivity as that of a conventional thermal cycler.

[Multiplex real-time PCR method for rapid detection of Marburg virus and Ebola virus].

PubMed

Yang, Yu; Bai, Lin; Hu, Kong-Xin; Yang, Zhi-Hong; Hu, Jian-Ping; Wang, Jing

2012-08-01

Marburg virus and Ebola virus are acute infections with high case fatality rates. A rapid, sensitive detection method was established to detect Marburg virus and Ebola virus by multiplex real-time fluorescence quantitative PCR. Designing primers and Taqman probes from highly conserved sequences of Marburg virus and Ebola virus through whole genome sequences alignment, Taqman probes labeled by FAM and Texas Red, the sensitivity of the multiplex real-time quantitative PCR assay was optimized by evaluating the different concentrations of primers and Probes. We have developed a real-time PCR method with the sensitivity of 30.5 copies/microl for Marburg virus positive plasmid and 28.6 copies/microl for Ebola virus positive plasmids, Japanese encephalitis virus, Yellow fever virus, Dengue virus were using to examine the specificity. The Multiplex real-time PCR assays provide a sensitive, reliable and efficient method to detect Marburg virus and Ebola virus simultaneously.

Real time non invasive imaging of fatty acid uptake in vivo

PubMed Central

Henkin, Amy H.; Cohen, Allison S.; Dubikovskaya, Elena A.; Park, Hyo Min; Nikitin, Gennady F.; Auzias, Mathieu G.; Kazantzis, Melissa; Bertozzi, Carolyn R.; Stahl, Andreas

2012-01-01

Detection and quantification of fatty acid fluxes in animal model systems following physiological, pathological, or pharmacological challenges is key to our understanding of complex metabolic networks as these macronutrients also activate transcription factors and modulate signaling cascades including insulin-sensitivity. To enable non-invasive, real-time, spatiotemporal quantitative imaging of fatty acid fluxes in animals, we created a bioactivatable molecular imaging probe based on long-chain fatty acids conjugated to a reporter molecule (luciferin). We show that this probe faithfully recapitulates cellular fatty acid uptake and can be used in animal systems as a valuable tool to localize and quantitate in real-time lipid fluxes such as intestinal fatty acid absorption and brown adipose tissue activation. This imaging approach should further our understanding of basic metabolic processes and pathological alterations in multiple disease models. PMID:22928772

Clinical Impact and Implication of Real-Time Oscillation Analysis for Language Mapping.

PubMed

Ogawa, Hiroshi; Kamada, Kyousuke; Kapeller, Christoph; Prueckl, Robert; Takeuchi, Fumiya; Hiroshima, Satoru; Anei, Ryogo; Guger, Christoph

2017-01-01

We developed a functional brain analysis system that enabled us to perform real-time task-related electrocorticography (ECoG) and evaluated its potential in clinical practice. We hypothesized that high gamma activity (HGA) mapping would provide better spatial and temporal resolution with high signal-to-noise ratios. Seven awake craniotomy patients were evaluated. ECoG was recorded during language tasks using subdural grids, and HGA (60-170 Hz) maps were obtained in real time. The patients also underwent electrocortical stimulation (ECS) mapping to validate the suspected functional locations on HGA mapping. The results were compared and calculated to assess the sensitivity and specificity of HGA mapping. For reference, bedside HGA-ECS mapping was performed in 5 epilepsy patients. HGA mapping demonstrated functional brain areas in real time and was comparable with ECS mapping. Sensitivity and specificity for the language area were 90.1% ± 11.2% and 90.0% ± 4.2%, respectively. Most HGA-positive areas were consistent with ECS-positive regions in both groups, and there were no statistical between-group differences. Although this study included a small number of subjects, it showed real-time HGA mapping with the same setting and tasks under different conditions. This study demonstrates the clinical feasibility of real-time HGA mapping. Real-time HGA mapping enabled simple and rapid detection of language functional areas in awake craniotomy. The mapping results were highly accurate, although the mapping environment was noisy. Further studies of HGA mapping may provide the potential to elaborate complex brain functions and networks. Copyright © 2016 Elsevier Inc. All rights reserved.

Geomagnetic Observatory Data for Real-Time Applications

NASA Astrophysics Data System (ADS)

Love, J. J.; Finn, C. A.; Rigler, E. J.; Kelbert, A.; Bedrosian, P.

2015-12-01

The global network of magnetic observatories represents a unique collective asset for the scientific community. Historically, magnetic observatories have supported global magnetic-field mapping projects and fundamental research of the Earth's interior and surrounding space environment. More recently, real-time data streams from magnetic observatories have become an important contributor to multi-sensor, operational monitoring of evolving space weather conditions, especially during magnetic storms. In this context, the U.S. Geological Survey (1) provides real-time observatory data to allied space weather monitoring projects, including those of NOAA, the U.S. Air Force, NASA, several international agencies, and private industry, (2) collaborates with Schlumberger to provide real-time geomagnetic data needed for directional drilling for oil and gas in Alaska, (3) develops products for real-time evaluation of hazards for the electric-power grid industry that are associated with the storm-time induction of geoelectric fields in the Earth's conducting lithosphere. In order to implement strategic priorities established by the USGS Natural Hazards Mission Area and the National Science and Technology Council, and with a focus on developing new real-time products, the USGS is (1) leveraging data management protocols already developed by the USGS Earthquake Program, (2) developing algorithms for mapping geomagnetic activity, a collaboration with NASA and NOAA, (3) supporting magnetotelluric surveys and developing Earth conductivity models, a collaboration with Oregon State University and the NSF's EarthScope Program, (4) studying the use of geomagnetic activity maps and Earth conductivity models for real-time estimation of geoelectric fields, (5) initiating geoelectric monitoring at several observatories, (6) validating real-time estimation algorithms against historical geomagnetic and geoelectric data. The success of these long-term projects is subject to funding constraints and will require coordination with partners in government, academia, and private industry.

Use of TV in space science activities - Some considerations. [onboard primary experimental data recording

NASA Technical Reports Server (NTRS)

Bannister, T. C.

1977-01-01

Advantages in the use of TV on board satellites as the primary data-recording system in a manned space laboratory when certain types of experiments are flown are indicated. Real-time or near-real-time validation, elimination of film weight, improved depth of field and low-light sensitivity, and better adaptability to computer and electronic processing of data are spelled out as advantages of TV over photographic techniques, say, in fluid dynamics experiments, and weightlessness studies.

Expanding Access and Usage of NASA Near Real-Time Imagery and Data

NASA Astrophysics Data System (ADS)

Cechini, M.; Murphy, K. J.; Boller, R. A.; Schmaltz, J. E.; Thompson, C. K.; Huang, T.; McGann, J. M.; Ilavajhala, S.; Alarcon, C.; Roberts, J. T.

2013-12-01

In late 2009, the Land Atmosphere Near-real-time Capability for EOS (LANCE) was created to greatly expand the range of near real-time data products from a variety of Earth Observing System (EOS) instruments. Since that time, NASA's Earth Observing System Data and Information System (EOSDIS) developed the Global Imagery Browse Services (GIBS) to provide highly responsive, scalable, and expandable imagery services that distribute near real-time imagery in an intuitive and geo-referenced format. The GIBS imagery services provide access through standards-based protocols such as the Open Geospatial Consortium (OGC) Web Map Tile Service (WMTS) and standard mapping file formats such as the Keyhole Markup Language (KML). Leveraging these standard mechanisms opens NASA near real-time imagery to a broad landscape of mapping libraries supporting mobile applications. By easily integrating with mobile application development libraries, GIBS makes it possible for NASA imagery to become a reliable and valuable source for end-user applications. Recently, EOSDIS has taken steps to integrate near real-time metadata products into the EOS ClearingHOuse (ECHO) metadata repository. Registration of near real-time metadata allows for near real-time data discovery through ECHO clients. In kind with the near real-time data processing requirements, the ECHO ingest model allows for low-latency metadata insertion and updates. Combining with the ECHO repository, the fast visual access of GIBS imagery can now be linked directly back to the source data file(s). Through the use of discovery standards such as OpenSearch, desktop and mobile applications can connect users to more than just an image. As data services, such as OGC Web Coverage Service, become more prevalent within the EOSDIS system, applications may even be able to connect users from imagery to data values. In addition, the full resolution GIBS imagery provides visual context to other GIS data and tools. The NASA near real-time imagery covers a broad set of Earth science disciplines. By leveraging the ECHO and GIBS services, these data can become a visual context within which other GIS activities are performed. The focus of this presentation is to discuss the GIBS imagery and ECHO metadata services facilitating near real-time discovery and usage. Existing synergies and future possibilities will also be discussed. The NASA Worldview demonstration client will be used to show an existing application combining the ECHO and GIBS services.

Real time eye tracking using Kalman extended spatio-temporal context learning

NASA Astrophysics Data System (ADS)

Munir, Farzeen; Minhas, Fayyaz ul Amir Asfar; Jalil, Abdul; Jeon, Moongu

2017-06-01

Real time eye tracking has numerous applications in human computer interaction such as a mouse cursor control in a computer system. It is useful for persons with muscular or motion impairments. However, tracking the movement of the eye is complicated by occlusion due to blinking, head movement, screen glare, rapid eye movements, etc. In this work, we present the algorithmic and construction details of a real time eye tracking system. Our proposed system is an extension of Spatio-Temporal context learning through Kalman Filtering. Spatio-Temporal Context Learning offers state of the art accuracy in general object tracking but its performance suffers due to object occlusion. Addition of the Kalman filter allows the proposed method to model the dynamics of the motion of the eye and provide robust eye tracking in cases of occlusion. We demonstrate the effectiveness of this tracking technique by controlling the computer cursor in real time by eye movements.

Real-time Quaking-induced Conversion Assay for Detection of CWD Prions in Fecal Material.

PubMed

Cheng, Yo Ching; Hannaoui, Samia; John, Theodore Ralph; Dudas, Sandor; Czub, Stefanie; Gilch, Sabine

2017-09-29

The RT-QuIC technique is a sensitive in vitro cell-free prion amplification assay based mainly on the seeded misfolding and aggregation of recombinant prion protein (PrP) substrate using prion seeds as a template for the conversion. RT-QuIC is a novel high-throughput technique which is analogous to real-time polymerase chain reaction (PCR). Detection of amyloid fibril growth is based on the dye Thioflavin T, which fluoresces upon specific interaction with ᵦ-sheet rich proteins. Thus, amyloid formation can be detected in real time. We attempted to develop a reliable non-invasive screening test to detect chronic wasting disease (CWD) prions in fecal extract. Here, we have specifically adapted the RT-QuIC technique to reveal PrP Sc seeding activity in feces of CWD infected cervids. Initially, the seeding activity of the fecal extracts we prepared was relatively low in RT-QuIC, possibly due to potential assay inhibitors in the fecal material. To improve seeding activity of feces extracts and remove potential assay inhibitors, we homogenized the fecal samples in a buffer containing detergents and protease inhibitors. We also submitted the samples to different methodologies to concentrate PrP Sc on the basis of protein precipitation using sodium phosphotungstic acid, and centrifugal force. Finally, the feces extracts were tested by optimized RT-QuIC which included substrate replacement in the protocol to improve the sensitivity of detection. Thus, we established a protocol for sensitive detection of CWD prion seeding activity in feces of pre-clinical and clinical cervids by RT-QuIC, which can be a practical tool for non-invasive CWD diagnosis.

Evaluation of laboratory tests for dengue diagnosis in clinical specimens from consecutive patients with suspected dengue in Belo Horizonte, Brazil.

PubMed

Ferraz, Fernanda Oliveira; Bomfim, Maria Rosa Quaresma; Totola, Antônio Helvécio; Ávila, Thiago Vinícius; Cisalpino, Daniel; Pessanha, José Eduardo Marques; da Glória de Souza, Danielle; Teixeira Júnior, Antônio Lúcio; Nogueira, Maurício Lacerda; Bruna-Romero, Oscar; Teixeira, Mauro Martins

2013-09-01

Dengue is a widely spread arboviral disease in tropical and subtropical regions of the world. Dengue fever presents clinical characteristics similar to other febrile illness. Thus laboratory diagnosis is important for adequate management of the disease. The present study was designed to evaluate the diagnostic performance of real-time PCR and serological methods for dengue in a real epidemic context. Clinical data and blood samples were collected from consecutive patients with suspected dengue who attended a primary health care unit in Belo Horizonte, Brazil. Serologic methods and real-time PCR were performed in serum samples to confirm dengue diagnosis. Among the 181 consecutive patients enrolled in this study with suspected dengue, 146 were considered positive by serological criteria (positive NS1 ELISA and/or anti-dengue IgM ELISA) and 138 were positive by real-time PCR. Clinical criteria were not sufficient for distinguishing between dengue and non-dengue febrile illness. The PCR reaction was pre-optimized using samples from patients with known viral infection. It had similar sensitivity compared to NS1 ELISA (88% and 89%, respectively). We also evaluated three commercial lateral flow immunochromatographic tests for NS1 detection (BIOEASY, BIORAD and PANBIO). All three tests showed high sensitivity (94%, 91% and 81%, respectively) for dengue diagnosis. According to our results it can be suggested that lateral flow tests for NS1 detection are the most feasible methods for early diagnosis of dengue. Copyright © 2013 Elsevier B.V. All rights reserved.

Searching for the best real-time RT-PCRs to detect Zika virus infections: the importance of comparing several protocols.

PubMed

de Moraes, F M; Espósito, D L A; Klein, T M; da Fonseca, B A L

2018-01-01

Clinical manifestations of Zika, dengue, and chikungunya virus infections are very similar, making it difficult to reach a diagnosis based only on clinical grounds. In addition, there is an intense cross-reactivity between antibodies directed to Zika virus and other flaviviruses, and an accurate Zika diagnosis is best achieved by real-time RT-PCR. However, some real-time RT-PCR show better performance than others. To reach the best possible Zika diagnosis, the analytic sensitivity of some probe-based real-time RT-PCR amplifying Zika virus RNA was evaluated in spiked and clinical samples. We evaluated primers and probes to detect Zika virus, which had been published before, and tested sensitivity using serum spiked and patient samples by real-time RT-PCR. When tested against spiked samples, the previously described primers showed different sensitivity, with very similar results when samples from patients (serum and urine) were analyzed. Real-time RT-PCR designed to amplify Zika virus NS1 showed the best analytical sensitivity for all samples.

BK virus DNA detection by real-time polymerase chain reaction in clinical specimens.

PubMed

Marchetti, Simona; Graffeo, Rosalia; Siddu, Alessia; Santangelo, Rosaria; Ciotti, Marco; Picardi, Alessandra; Favalli, Cartesio; Fadda, Giovanni; Cattani, Paola

2007-04-01

The BK polyomavirus (BKV) is widespread in the general population. In transplant recipients, the patients' weakened immune response may encourage reactivation of latent infection, leading to BKV-related diseases. Rapid and quantitative detection might help to delineate viral reactivation patterns and could thus play an important role in their clinical management. In our study we developed an "in-house" quantitative real-time PCR to detect BKV DNA. The effectiveness of this assay was evaluated by a retrospective analysis of 118 plasma specimens from 22 bone marrow transplant (BMT) recipients and 107 samples from immunocompetent subjects. Eight (36.3%) of the 22 bone marrow transplant recipients tested positive for BKV. The viral load varied from specimen to specimen (10 to 10(5) copies/ml). BKV related disease like hemorrhagic cystitis (HC) was diagnosed in three patients. Specimens from the control group all tested negative. Our results showed the high sensitivity of the real-time PCR, allowing accurate and reproducible measuring of the viral load in order to identify patients at risk for BKV-related diseases. With due caution in interpreting threshold values, the real-time PCR could provide a rapid, sensitive and specific tool for detecting BKV and distinguishing latent and active infection.

[Analytical performances of real-time PCR by Abbott RealTime CMV with m2000 for the detection of cytomegalovirus in urine].

PubMed

De Monte, Anne; Cannavo, Isabelle; Caramella, Anne; Ollier, Laurence; Giordanengo, Valérie

2016-01-01

Congenital cytomegalovirus (CMV) infection is the leading cause of sensoneurinal disability due to infectious congenital disease. The diagnosis of congenital CMV infection is based on the search of CMV in the urine within the first two weeks of life. Viral culture of urine is the gold standard. However, the PCR is highly sensitive and faster. It is becoming an alternative choice. The objective of this study is the validation of real-time PCR by Abbott RealTime CMV with m2000 for the detection of cytomegalovirus in urine. Repeatability, reproducibility, detection limit and inter-sample contamination were evaluated. Urine samples from patients (n=141) were collected and analyzed simultaneously in culture and PCR in order to assess the correlation of these two methods. The sensitivity and specificity of PCR were also calculated. The Abbott RealTime CMV PCR in urine is an automated and sensitive method (detection limit 200 UI/mL). Fidelity is very good (standard deviation of repeatability: 0.08 to 0.15 LogUI/mL and reproducibility 0.18 LogUI/mL). We can note a good correlation between culture and Abbott RealTime CMV PCR (kappa 96%). When considering rapid culture as reference, real-time PCR was highly sensitive (100%) and specific (98.2%). The real-time PCR by Abbott RealTime CMV with m2000 is optimal for CMV detection in urine.

Modular Bayesian Networks with Low-Power Wearable Sensors for Recognizing Eating Activities.

PubMed

Kim, Kee-Hoon; Cho, Sung-Bae

2017-12-11

Recently, recognizing a user's daily activity using a smartphone and wearable sensors has become a popular issue. However, in contrast with the ideal definition of an experiment, there could be numerous complex activities in real life with respect to its various background and contexts: time, space, age, culture, and so on. Recognizing these complex activities with limited low-power sensors, considering the power and memory constraints of the wearable environment and the user's obtrusiveness at once is not an easy problem, although it is very crucial for the activity recognizer to be practically useful. In this paper, we recognize activity of eating, which is one of the most typical examples of a complex activity, using only daily low-power mobile and wearable sensors. To organize the related contexts systemically, we have constructed the context model based on activity theory and the "Five W's", and propose a Bayesian network with 88 nodes to predict uncertain contexts probabilistically. The structure of the proposed Bayesian network is designed by a modular and tree-structured approach to reduce the time complexity and increase the scalability. To evaluate the proposed method, we collected the data with 10 different activities from 25 volunteers of various ages, occupations, and jobs, and have obtained 79.71% accuracy, which outperforms other conventional classifiers by 7.54-14.4%. Analyses of the results showed that our probabilistic approach could also give approximate results even when one of contexts or sensor values has a very heterogeneous pattern or is missing.

Real-time PCR assays for detection of Brucella spp. and the identification of genotype ST27 in bottlenose dolphins (Tursiops truncatus).

PubMed

Wu, Qingzhong; McFee, Wayne E; Goldstein, Tracey; Tiller, Rebekah V; Schwacke, Lori

2014-05-01

Rapid detection of Brucella spp. in marine mammals is challenging. Microbiologic culture is used for definitive diagnosis of brucellosis, but is time consuming, has low sensitivity and can be hazardous to laboratory personnel. Serological methods can aid in diagnosis, but may not differentiate prior exposure versus current active infection and may cross-react with unrelated Gram-negative bacteria. This study reports a real-time PCR assay for the detection of Brucella spp. and application to screen clinical samples from bottlenose dolphins stranded along the coast of South Carolina, USA. The assay was found to be 100% sensitive for the Brucella strains tested, and the limit of detection was 0.27fg of genomic DNA from Brucella ceti B1/94 per PCR volume. No amplification was detected for the non-Brucella pathogens tested. Brucella DNA was detected in 31% (55/178) of clinical samples tested. These studies indicate that the real-time PCR assay is highly sensitive and specific for the detection of Brucella spp. in bottlenose dolphins. We also developed a second real-time PCR assay for rapid identification of Brucella ST27, a genotype that is associated with human zoonotic infection. Positive results were obtained for Brucella strains which had been identified as ST27 by multilocus sequence typing. No amplification was found for other Brucella strains included in this study. ST27 was identified in 33% (18/54) of Brucella spp. DNA-positive clinical samples. To our knowledge, this is the first report on the use of a real-time PCR assay for identification of Brucella genotype ST27 in marine mammals. Copyright © 2014 Elsevier B.V. All rights reserved.

The Smartphone Brain Scanner: A Portable Real-Time Neuroimaging System

PubMed Central

Stopczynski, Arkadiusz; Stahlhut, Carsten; Larsen, Jakob Eg; Petersen, Michael Kai; Hansen, Lars Kai

2014-01-01

Combining low-cost wireless EEG sensors with smartphones offers novel opportunities for mobile brain imaging in an everyday context. Here we present the technical details and validation of a framework for building multi-platform, portable EEG applications with real-time 3D source reconstruction. The system – Smartphone Brain Scanner – combines an off-the-shelf neuroheadset or EEG cap with a smartphone or tablet, and as such represents the first fully portable system for real-time 3D EEG imaging. We discuss the benefits and challenges, including technical limitations as well as details of real-time reconstruction of 3D images of brain activity. We present examples of brain activity captured in a simple experiment involving imagined finger tapping, which shows that the acquired signal in a relevant brain region is similar to that obtained with standard EEG lab equipment. Although the quality of the signal in a mobile solution using an off-the-shelf consumer neuroheadset is lower than the signal obtained using high-density standard EEG equipment, we propose mobile application development may offset the disadvantages and provide completely new opportunities for neuroimaging in natural settings. PMID:24505263

Fast Context Switching in Real-Time Propositional Reasoning

NASA Technical Reports Server (NTRS)

Nayak, P. Pandurang; Williams, Brian C.

1997-01-01

The trend to increasingly capable and affordable control processors has generated an explosion of embedded real-time gadgets that serve almost every function imaginable. The daunting task of programming these gadgets is greatly alleviated with real-time deductive engines that perform all execution and monitoring functions from a single core model, Fast response times are achieved using an incremental propositional deductive database (an LTMS). Ideally the cost of an LTMS's incremental update should be linear in the number of labels that change between successive contexts. Unfortunately an LTMS can expend a significant percentage of its time working on labels that remain constant between contexts. This is caused by the LTMS's conservative approach: a context switch first removes all consequences of deleted clauses, whether or not those consequences hold in the new context. This paper presents a more aggressive incremental TMS, called the ITMS, that avoids processing a significant number of these consequences that are unchanged. Our empirical evaluation for spacecraft control shows that the overhead of processing unchanged consequences can be reduced by a factor of seven.

Protocol for the use of light upon extension real-time PCR for the determination of viral load in HBV infection.

PubMed

Li, Guimin; Li, Wangfeng; Liu, Lixia

2012-01-01

Real-time PCR has engendered wide acceptance for quantitation of hepatitis B virus (HBV) DNA in the blood due to its improved rapidity, sensitivity, reproducibility, and reduced contamination. Here we describe a cost-effective and highly sensitive HBV real-time quantitative assay based on the light upon extension real-time PCR platform and a simple and reliable HBV DNA preparation method using silica-coated magnetic beads.

Enhancement of Temporal Resolution and BOLD Sensitivity in Real-Time fMRI using Multi-Slab Echo-Volumar Imaging

PubMed Central

Posse, Stefan; Ackley, Elena; Mutihac, Radu; Rick, Jochen; Shane, Matthew; Murray-Krezan, Cristina; Zaitsev, Maxim; Speck, Oliver

2012-01-01

In this study, a new approach to high-speed fMRI using multi-slab echo-volumar imaging (EVI) is developed that minimizes geometrical image distortion and spatial blurring, and enables nonaliased sampling of physiological signal fluctuation to increase BOLD sensitivity compared to conventional echo-planar imaging (EPI). Real-time fMRI using whole brain 4-slab EVI with 286 ms temporal resolution (4 mm isotropic voxel size) and partial brain 2-slab EVI with 136 ms temporal resolution (4×4×6 mm3 voxel size) was performed on a clinical 3 Tesla MRI scanner equipped with 12-channel head coil. Four-slab EVI of visual and motor tasks significantly increased mean (visual: 96%, motor: 66%) and maximum t-score (visual: 263%, motor: 124%) and mean (visual: 59%, motor: 131%) and maximum (visual: 29%, motor: 67%) BOLD signal amplitude compared with EPI. Time domain moving average filtering (2 s width) to suppress physiological noise from cardiac and respiratory fluctuations further improved mean (visual: 196%, motor: 140%) and maximum (visual: 384%, motor: 200%) t-scores and increased extents of activation (visual: 73%, motor: 70%) compared to EPI. Similar sensitivity enhancement, which is attributed to high sampling rate at only moderately reduced temporal signal-to-noise ratio (mean: − 52%) and longer sampling of the BOLD effect in the echo-time domain compared to EPI, was measured in auditory cortex. Two-slab EVI further improved temporal resolution for measuring task-related activation and enabled mapping of five major resting state networks (RSNs) in individual subjects in 5 min scans. The bilateral sensorimotor, the default mode and the occipital RSNs were detectable in time frames as short as 75 s. In conclusion, the high sampling rate of real-time multi-slab EVI significantly improves sensitivity for studying the temporal dynamics of hemodynamic responses and for characterizing functional networks at high field strength in short measurement times. PMID:22398395

Context-aware personal navigation using embedded sensor fusion in smartphones.

PubMed

Saeedi, Sara; Moussa, Adel; El-Sheimy, Naser

2014-03-25

Context-awareness is an interesting topic in mobile navigation scenarios where the context of the application is highly dynamic. Using context-aware computing, navigation services consider the situation of user, not only in the design process, but in real time while the device is in use. The basic idea is that mobile navigation services can provide different services based on different contexts-where contexts are related to the user's activity and the device placement. Context-aware systems are concerned with the following challenges which are addressed in this paper: context acquisition, context understanding, and context-aware application adaptation. The proposed approach in this paper is using low-cost sensors in a multi-level fusion scheme to improve the accuracy and robustness of context-aware navigation system. The experimental results demonstrate the capabilities of the context-aware Personal Navigation Systems (PNS) for outdoor personal navigation using a smartphone.

SERS activity of Ag decorated nanodiamond and nano-β-SiC, diamond-like-carbon and thermally annealed diamond thin film surfaces.

PubMed

Kuntumalla, Mohan Kumar; Srikanth, Vadali Venkata Satya Siva; Ravulapalli, Satyavathi; Gangadharini, Upender; Ojha, Harish; Desai, Narayana Rao; Bansal, Chandrahas

2015-09-07

In the recent past surface enhanced Raman scattering (SERS) based bio-sensing has gained prominence owing to the simplicity and efficiency of the SERS technique. Dedicated and continuous research efforts have been made to develop SERS substrates that are not only stable, durable and reproducible but also facilitate real-time bio-sensing. In this context diamond, β-SiC and diamond-like-carbon (DLC) and other related thin films have been promoted as excellent candidates for bio-technological applications including real time bio-sensing. In this work, SERS activities of nanodiamond, nano-β-SiC, DLC, thermally annealed diamond thin film surfaces were examined. DLC and thermally annealed diamond thin films were found to show SERS activity without any metal nanostructures on their surfaces. The observed SERS activities of the considered surfaces are explained in terms of the electromagnetic enhancement mechanism and charge transfer resonance process.

Aim, Shoot, Ready! Future Teachers Learn to Do Video

ERIC Educational Resources Information Center

Hernandez-Ramos, Pedro

2007-01-01

This paper describes an intensive 2-hr workshop designed to introduce preservice teachers to digital video in the context of an instructional technology course or as a stand-alone activity. Acknowledging time constraints in most real-life instructional situations, this format takes novices with no or very limited knowledge of video making to the…

Context-Aware Personal Navigation Using Embedded Sensor Fusion in Smartphones

PubMed Central

Saeedi, Sara; Moussa, Adel; El-Sheimy, Naser

2014-01-01

Context-awareness is an interesting topic in mobile navigation scenarios where the context of the application is highly dynamic. Using context-aware computing, navigation services consider the situation of user, not only in the design process, but in real time while the device is in use. The basic idea is that mobile navigation services can provide different services based on different contexts—where contexts are related to the user's activity and the device placement. Context-aware systems are concerned with the following challenges which are addressed in this paper: context acquisition, context understanding, and context-aware application adaptation. The proposed approach in this paper is using low-cost sensors in a multi-level fusion scheme to improve the accuracy and robustness of context-aware navigation system. The experimental results demonstrate the capabilities of the context-aware Personal Navigation Systems (PNS) for outdoor personal navigation using a smartphone. PMID:24670715

A real time dynamic data acquisition and processing system for velocity, density, and total temperature fluctuation measurements

NASA Technical Reports Server (NTRS)

Clukey, Steven J.

1991-01-01

The real time Dynamic Data Acquisition and Processing System (DDAPS) is described which provides the capability for the simultaneous measurement of velocity, density, and total temperature fluctuations. The system of hardware and software is described in context of the wind tunnel environment. The DDAPS replaces both a recording mechanism and a separate data processing system. DDAPS receives input from hot wire anemometers. Amplifiers and filters condition the signals with computer controlled modules. The analog signals are simultaneously digitized and digitally recorded on disk. Automatic acquisition collects necessary calibration and environment data. Hot wire sensitivities are generated and applied to the hot wire data to compute fluctuations. The presentation of the raw and processed data is accomplished on demand. The interface to DDAPS is described along with the internal mechanisms of DDAPS. A summary of operations relevant to the use of the DDAPS is also provided.

Multichannel wearable system dedicated for simultaneous electroencephalography/near-infrared spectroscopy real-time data acquisitions

NASA Astrophysics Data System (ADS)

Lareau, Etienne; Lesage, Frederic; Pouliot, Philippe; Nguyen, Dang; Le Lan, Jerome; Sawan, Mohamad

2011-09-01

Functional neuroimaging is becoming a valuable tool in cognitive research and clinical applications. The clinical context brings specific constraints that include the requirement of a high channel count to cover the whole head, high sensitivity for single event detection, and portability for long-term bedside monitoring. For epilepsy and stroke monitoring, the combination of electroencephalography (EEG) and functional near-infrared spectroscopy (NIRS) is expected to provide useful clinical information, and efforts have been deployed to create prototypes able to simultaneously acquire both measurement modalities. However, to the best of our knowledge, existing systems lack portability, NIRS sensitivity, or have low channel count. We present a battery-powered, portable system with potentially up to 32 EEG channels, 32 NIRS light sources, and 32 detectors. Avalanche photodiodes allow for high NIRS sensitivity and the autonomy of the system is over 24 h. A reduced channel count prototype with 8 EEG channels, 8 sources, and 8 detectors was tested on phantoms. Further validation was done on five healthy adults using a visual stimulation protocol to detect local hemodynamic changes and visually evoked potentials. Results show good concordance with literature regarding functional activations and suggest sufficient performance for clinical use, provided some minor adjustments were made.

Experience with Using the Sensewear BMS Sensor System in the Context of a Health and Wellbeing Application

PubMed Central

Jones, Val; Bults, Richard; de Wijk, Rene; Widya, Ing; Batista, Ricardo; Hermens, Hermie

2011-01-01

An assessment of a sensor designed for monitoring energy expenditure, activity, and sleep was conducted in the context of a research project which develops a weight management application. The overall goal of this project is to affect sustainable behavioural change with respect to diet and exercise in order to improve health and wellbeing. This paper reports results of a pretrial in which three volunteers wore the sensor for a total of 11 days. The aim was to gain experience with the sensor and determine if it would be suitable for incorporation into the ICT system developed by the project to be trialled later on a larger population. In this paper we focus mainly on activity monitoring and user experience. Data and results including visualizations and reports are presented and discussed. User experience proved positive in most respects. Exercise levels and sleep patterns correspond to user logs relating to exercise sessions and sleep patterns. Issues raised relate to accuracy, one source of possible interference, the desirability of enhancing the system with real-time data transmission, and analysis to enable real-time feedback. It is argued that automatic activity classification is needed to properly analyse and interpret physical activity data captured by accelerometry. PMID:21772840

Perirectal Swab Surveillance for Clostridium difficile by Use of Selective Broth Preamplification and Real-Time PCR Detection of tcdB ▿

PubMed Central

Curry, Scott R.; Schlackman, Jessica L.; Hamilton, Travis M.; Henderson, Tatianna K.; Brown, Nakita T.; Marsh, Jane W.; Shutt, Kathleen A.; Brooks, Maria M.; Pasculle, A. William; Muto, Carlene A.; Harrison, Lee H.

2011-01-01

Active surveillance testing to identify and isolate asymptomatic carriers of toxigenic Clostridium difficile has been limited by the lack of a test that is sensitive, specific, and timely enough to serve as an infection control tool. We tested DNA preamplified from perirectal surveillance specimens in a liquid medium selective for C. difficile by using a modified commercial real-time PCR assay. All fermenting specimens were subcultured, and isolates were tested for toxigenicity. Culture-positive toxigenic isolates served as the gold standard for comparison with the broth preamplification/PCR assay. The limit of detection for the assay was 1 CFU. Relative to toxigenic anaerobic culture, the sensitivity, specificity, and positive and negative predictive values of this assay were 70/70 (100.0%), 422/426 (99.1%), 70/74 (94.6%), and 422/422 (100.0%), respectively. These data demonstrate that selective broth preamplification and real-time PCR of perirectal swab specimens constitute a practical approach to the detection of asymptomatic C. difficile carriage. PMID:21880961

A Case Study of On-the-fly Wide-field Radio Imaging Applied to the Gravitational Wave Event GW151226

NASA Astrophysics Data System (ADS)

Mooley, K. P.; Frail, D. A.; Myers, S. T.; Kulkarni, S. R.; Hotokezaka, K.; Singer, L. P.; Horesh, A.; Kasliwal, M. M.; Cenko, S. B.; Hallinan, G.

2018-04-01

We apply a newly developed on-the-fly mosaicing technique on the Jansky Very Large Array (VLA) at 3 GHz in order to carry out a sensitive search for an afterglow from the Advanced LIGO binary black hole merger event GW151226. In three epochs between 1.5 and 6 months post-merger, we observed a 100 deg2 region, with more than 80% of the survey region having an rms sensitivity of better than 150 μJy/beam, in the northern hemisphere with a merger containment probability of 10%. The data were processed in near real time and analyzed to search for transients and variables. No transients were found but we have demonstrated the ability to conduct blind searches in a time-frequency phase space where the predicted afterglow signals are strongest. If the gravitational wave event is contained within our survey region, the upper limit on any late-time radio afterglow from the merger event at an assumed mean distance of 440 Mpc is about 1029 erg s‑1 Hz‑1. Approximately 1.5% of the radio sources in the field showed variability at a level of 30%, and can be attributed to normal activity from active galactic nuclei. The low rate of false positives in the radio sky suggests that wide-field imaging searches at a few Gigahertz can be an efficient and competitive search strategy. We discuss our search method in the context of the recent afterglow detection from GW170817 and radio follow-up in future gravitational wave observing runs.

Volcanology curricula development aided by online educational resource

USGS Publications Warehouse

Poland, Michael P.; van der Hoeven Kraft, Katrien J.; Teasdale, Rachel

2011-01-01

Volcanic activity is an excellent hook for engaging college and university students in geoscience classes. An increasing number of Internet-accessible real-time and near–real time volcano monitoring data are now available and constitute an important resource for geoscience education; however, relatively few data sets are comprehensive, and many lack background information to aid in interpretation. In response to the need for organized, accessible, and well-documented volcano education resources, the U.S. Geological Survey's Hawaiian Volcano Observatory (HVO), in collaboration with NASA and the University of Hawai`i at Manoa, established the Volcanoes Exploration Project: Pu`u `Ō`ō (VEPP). The VEPP Web site (http://vepp.wr.usgs.gov) is an educational resource that provides access, in near real time, to geodetic, seismic, and geologic data from the active Pu`u `Ō`ō eruptive vent on Kilauea volcano, Hawaii, along with background and context information. A strength of the VEPP site is the common theme of the Pu`u `Ō`ō eruption, which allows the site to be revisited multiple times to demonstrate different principles and integrate many aspects of volcanology.

Adaptive Kalman filtering for real-time mapping of the visual field

PubMed Central

Ward, B. Douglas; Janik, John; Mazaheri, Yousef; Ma, Yan; DeYoe, Edgar A.

2013-01-01

This paper demonstrates the feasibility of real-time mapping of the visual field for clinical applications. Specifically, three aspects of this problem were considered: (1) experimental design, (2) statistical analysis, and (3) display of results. Proper experimental design is essential to achieving a successful outcome, particularly for real-time applications. A random-block experimental design was shown to have less sensitivity to measurement noise, as well as greater robustness to error in modeling of the hemodynamic impulse response function (IRF) and greater flexibility than common alternatives. In addition, random encoding of the visual field allows for the detection of voxels that are responsive to multiple, not necessarily contiguous, regions of the visual field. Due to its recursive nature, the Kalman filter is ideally suited for real-time statistical analysis of visual field mapping data. An important feature of the Kalman filter is that it can be used for nonstationary time series analysis. The capability of the Kalman filter to adapt, in real time, to abrupt changes in the baseline arising from subject motion inside the scanner and other external system disturbances is important for the success of clinical applications. The clinician needs real-time information to evaluate the success or failure of the imaging run and to decide whether to extend, modify, or terminate the run. Accordingly, the analytical software provides real-time displays of (1) brain activation maps for each stimulus segment, (2) voxel-wise spatial tuning profiles, (3) time plots of the variability of response parameters, and (4) time plots of activated volume. PMID:22100663

Development of real-time recombinase polymerase amplification assay for rapid and sensitive detection of canine parvovirus 2.

PubMed

Geng, Yunyun; Wang, Jianchang; Liu, Libing; Lu, Yan; Tan, Ke; Chang, Yan-Zhong

2017-11-06

Canine parvovirus 2, a linear single-stranded DNA virus belonging to the genus Parvovirus within the family Parvoviridae, is a highly contagious pathogen of domestic dogs and several wild canidae species. Early detection of canine parvovirus (CPV-2) is crucial to initiating appropriate outbreak control strategies. Recombinase polymerase amplification (RPA), a novel isothermal gene amplification technique, has been developed for the molecular detection of diverse pathogens. In this study, a real-time RPA assay was developed for the detection of CPV-2 using primers and an exo probe targeting the CPV-2 nucleocapsid protein gene. The real-time RPA assay was performed successfully at 38 °C, and the results were obtained within 4-12 min for 10 5 -10 1 molecules of template DNA. The assay only detected CPV-2, and did not show cross-detection of other viral pathogens, demonstrating a high level of specificity. The analytical sensitivity of the real-time RPA was 10 1 copies/reaction of a standard DNA template, which was 10 times more sensitive than the common RPA method. The clinical sensitivity of the real-time RPA assay matched 100% (n = 91) to the real-time PCR results. The real-time RPA assay is a simple, rapid, reliable and affordable method that can potentially be applied for the detection of CPV-2 in the research laboratory and point-of-care diagnosis.

Development and Evaluation of Real-Time Volumetric Compton Gamma-Ray Imaging

NASA Astrophysics Data System (ADS)

Barnowski, Ross Wegner

An approach to gamma-ray imaging has been developed that enables near real-time volumetric (3D) imaging of unknown environments thus improving the utility of gamma-ray imaging for source-search and radiation mapping applications. The approach, herein dubbed scene data fusion (SDF), is based on integrating mobile radiation imagers with real time tracking and scene reconstruction algorithms to enable a mobile mode of operation and 3D localization of gamma-ray sources. The real-time tracking allows the imager to be moved throughout the environment or around a particular object of interest, obtaining the multiple perspectives necessary for standoff 3D imaging. A 3D model of the scene, provided in real-time by a simultaneous localization and mapping (SLAM) algorithm, can be incorporated into the image reconstruction reducing the reconstruction time and improving imaging performance. The SDF concept is demonstrated in this work with a Microsoft Kinect RGB-D sensor, a real-time SLAM solver, and two different mobile gamma-ray imaging platforms. The first is a cart-based imaging platform known as the Volumetric Compton Imager (VCI), comprising two 3D position-sensitive high purity germanium (HPGe) detectors, exhibiting excellent gamma-ray imaging characteristics, but with limited mobility due to the size and weight of the cart. The second system is the High Efficiency Multimodal Imager (HEMI) a hand-portable gamma-ray imager comprising 96 individual cm3 CdZnTe crystals arranged in a two-plane, active-mask configuration. The HEMI instrument has poorer energy and angular resolution than the VCI, but is truly hand-portable, allowing the SDF concept to be tested in multiple environments and for more challenging imaging scenarios. An iterative algorithm based on Compton kinematics is used to reconstruct the gamma-ray source distribution in all three spatial dimensions. Each of the two mobile imaging systems are used to demonstrate SDF for a variety of scenarios, including general search and mapping scenarios with several point gamma-ray sources over the range of energies relevant for Compton imaging. More specific imaging scenarios are also addressed, including directed search and object interrogation scenarios. Finally, the volumetric image quality is quantitatively investigated with respect to the number of Compton events acquired during a measurement, the list-mode uncertainty of the Compton cone data, and the uncertainty in the pose estimate from the real-time tracking algorithm. SDF advances the real-world applicability of gamma-ray imaging for many search, mapping, and verification scenarios by improving the tractability of the gamma-ray image reconstruction and providing context for the 3D localization of gamma-ray sources within the environment in real-time.

“I Have No Clue What I Drunk Last Night” Using Smartphone Technology to Compare In-Vivo and Retrospective Self-Reports of Alcohol Consumption

PubMed Central

Monk, Rebecca Louise; Heim, Derek; Qureshi, Adam; Price, Alan

2015-01-01

Aim This research compared real-time measurements of alcohol consumption with retrospective accounts of alcohol consumption to examine possible discrepancies between, and contextual influences on, the different accounts. Method Building on previous investigations, a specifically designed Smartphone technology was utilized to measure alcohol consumption and contextual influences in de facto real-time. Real-time data (a total of 10,560 data points relating to type and number of drinks and current social / environmental context) were compared with daily and weekly retrospective accounts of alcohol consumption. Results Participants reported consuming more alcoholic drinks during real-time assessment than retrospectively. For daily accounts a higher number of drinks consumed in real-time was related to a higher discrepancy between real-time and retrospective accounts. This effect was found across all drink types but was not shaped by social and environmental contexts. Higher in-vivo alcohol consumption appeared to be related to a higher discrepancy in retrospectively reported weekly consumption for alcohol beverage types other than wine. When including contextual factors into the statistical models, being with two or more friends (as opposed to being alone) decreased the discrepancy between real-time and retrospective reports, whilst being in the pub (relative to being at home) was associated with greater discrepancies. Conclusions Overall, retrospective accounts may underestimate the amount of actual, real-time alcohol consumed. Increased consumption may also exacerbate differences between real-time and retrospective accounts. Nonetheless, this is not a global effect as environmental and social contexts interact with the type of alcohol consumed and the time frame given for reporting (weekly vs. daily retrospective). A degree of caution therefore appears warranted with regards to the use of retrospective self-report methods of recording alcohol consumption. Whilst real-time sampling is unlikely to be completely error free, it may be better able to account for social and environmental influences on self-reported consumption. PMID:25992573

Real-Time Process Analytics in Emergency Healthcare.

PubMed

Koufi, Vassiliki; Malamateniou, Flora; Prentza, Adrianna; Vassilacopoulos, George

2017-01-01

Emergency medical systems (EMS) are considered to be amongst the most crucial systems as they involve a variety of activities which are performed from the time of a call to an ambulance service till the time of patient's discharge from the emergency department of a hospital. These activities are closely interrelated so that collaboration and coordination becomes a vital issue for patients and for emergency healthcare service performance. The utilization of standard workflow technology in the context of Service Oriented Architecture can provide an appropriate technological infrastructure for defining and automating EMS processes that span organizational boundaries so that to create and empower collaboration and coordination among the participating organizations. In such systems, the utilization of leading-edge analytics tools can prove important as it can facilitate real-time extraction and visualization of useful insights from the mountains of generated data pertaining to emergency case management. This paper presents a framework which provides healthcare professionals with just-in-time insight within and across emergency healthcare processes by performing real-time analysis on process-related data in order to better support decision making and identify potential critical risks that may affect the provision of emergency care to patients.

Impact of study design on development and evaluation of an activity-type classifier.

PubMed

van Hees, Vincent T; Golubic, Rajna; Ekelund, Ulf; Brage, Søren

2013-04-01

Methods to classify activity types are often evaluated with an experimental protocol involving prescribed physical activities under confined (laboratory) conditions, which may not reflect real-life conditions. The present study aims to evaluate how study design may impact on classifier performance in real life. Twenty-eight healthy participants (21-53 yr) were asked to wear nine triaxial accelerometers while performing 58 activity types selected to simulate activities in real life. For each sensor location, logistic classifiers were trained in subsets of up to 8 activities to distinguish between walking and nonwalking activities and were then evaluated in all 58 activities. Different weighting factors were used to convert the resulting confusion matrices into an estimation of the confusion matrix as would apply in the real-life setting by creating four different real-life scenarios, as well as one traditional laboratory scenario. The sensitivity of a classifier estimated with a traditional laboratory protocol is within the range of estimates derived from real-life scenarios for any body location. The specificity, however, was systematically overestimated by the traditional laboratory scenario. Walking time was systematically overestimated, except for lower back sensor data (range: 7-757%). In conclusion, classifier performance under confined conditions may not accurately reflect classifier performance in real life. Future studies that aim to evaluate activity classification methods are warranted to pay special attention to the representativeness of experimental conditions for real-life conditions.

Wide-Field Fluorescence Microscopy of Real-Time Bioconjugation Sensing

PubMed Central

Szalkowski, Marcin; Sulowska, Karolina; Grzelak, Justyna; Niedziółka-Jönsson, Joanna; Roźniecka, Ewa

2018-01-01

We apply wide-field fluorescence microscopy to measure real-time attachment of photosynthetic proteins to plasmonically active silver nanowires. The observation of this effect is enabled, on the one hand, by sensitive detection of fluorescence and, on the other hand, by plasmonic enhancement of protein fluorescence. We examined two sample configurations with substrates being a bare glass coverslip and a coverslip functionalized with a monolayer of streptavidin. The different preparation of the substrate changes the observed behavior as far as attachment of the protein is concerned as well as its subsequent photobleaching. For the latter substrate the conjugation process is measurably slower. The described method can be universally applied in studying protein-nanostructure interactions for real-time fluorescence-based sensing. PMID:29351211

Wide-Field Fluorescence Microscopy of Real-Time Bioconjugation Sensing.

PubMed

Szalkowski, Marcin; Sulowska, Karolina; Grzelak, Justyna; Niedziółka-Jönsson, Joanna; Roźniecka, Ewa; Kowalska, Dorota; Maćkowski, Sebastian

2018-01-19

We apply wide-field fluorescence microscopy to measure real-time attachment of photosynthetic proteins to plasmonically active silver nanowires. The observation of this effect is enabled, on the one hand, by sensitive detection of fluorescence and, on the other hand, by plasmonic enhancement of protein fluorescence. We examined two sample configurations with substrates being a bare glass coverslip and a coverslip functionalized with a monolayer of streptavidin. The different preparation of the substrate changes the observed behavior as far as attachment of the protein is concerned as well as its subsequent photobleaching. For the latter substrate the conjugation process is measurably slower. The described method can be universally applied in studying protein-nanostructure interactions for real-time fluorescence-based sensing.

Visualization of Cortical Dynamics

NASA Astrophysics Data System (ADS)

Grinvald, Amiram

2003-03-01

Recent progress in studies of cortical dynamics will be reviewed including the combination of real time optical imaging based on voltage sensitive dyes, single and multi- unit recordings, LFP, intracellular recordings and microstimulation. To image the flow of neuronal activity from one cortical site to the next, in real time, we have used optical imaging based on newly designed voltage sensitive dyes and a Fuji 128x 128 fast camera which we modified. A factor of 20-40 fold improvement in the signal to noise ratio was obtained with the new dye during in vivo imaging experiments. This improvements has facilitates the exploration of cortical dynamics without signal averaging in the millisecond time domain. We confirmed that the voltage sensitive dye signal indeed reflects membrane potential changes in populations of neurons by showing that the time course of the intracellular activity recorded intracellularly from a single neuron was highly correlated in many cases with the optical signal from a small patch of cortex recorded nearby. We showed that the firing of single cortical neurons is not a random process but occurs when the on-going pattern of million of neurons is similar to the functional architecture map which correspond to the tuning properties of that neuron. Chronic optical imaging, combined with electrical recordings and microstimulation, over a long period of times of more than a year, was successfully applied also to the study of higher brain functions in the behaving macaque monkey.

Real-time spectroscopic monitoring of photocatalytic activity promoted by graphene in a microfluidic reactor

PubMed Central

Li, Yifan; Lin, Beichen; Ge, Likai; Guo, Hongchen; Chen, Xinyi; Lu, Miao

2016-01-01

Photocatalytic microreactors have been utilized as rapid, versatile platforms for the characterization of photocatalysts. In this work, a photocatalytic microreactor integrated with absorption spectroscopy was proposed for the real-time monitoring of photocatalytic activity using different catalysts. The validity of this method was investigated by the rapid screening on the photocatalytic performance of a titanium oxide (TiO2)-decorated graphene oxide (GO) sheet for the degradation of methylene blue under monochromatic visible irradiation. The sampling interval time could be minimized to 10 s for achieving real-time detection. The best photocatalytic activity was observed for an optimized TiO2/GO weight mixing ratio of 7:11, with a reaction rate constant up to 0.067 min−1. The addition of GO into TiO2 enhances photocatalytic activity and adsorption of MB molecules. The synthetic reaction rate constant was up to approximately 0.11 min−1, which was also the highest among the catalysts. The microreactor exhibited good sensitivity and reproducibility without weakening the performance of the photocatalysts. Consequently, the photocatalytic microreactor is promising as a simple, portable, and rapid screening tool for new photocatalysts. PMID:27346555

Real-time spectroscopic monitoring of photocatalytic activity promoted by graphene in a microfluidic reactor

NASA Astrophysics Data System (ADS)

Li, Yifan; Lin, Beichen; Ge, Likai; Guo, Hongchen; Chen, Xinyi; Lu, Miao

2016-06-01

Photocatalytic microreactors have been utilized as rapid, versatile platforms for the characterization of photocatalysts. In this work, a photocatalytic microreactor integrated with absorption spectroscopy was proposed for the real-time monitoring of photocatalytic activity using different catalysts. The validity of this method was investigated by the rapid screening on the photocatalytic performance of a titanium oxide (TiO2)-decorated graphene oxide (GO) sheet for the degradation of methylene blue under monochromatic visible irradiation. The sampling interval time could be minimized to 10 s for achieving real-time detection. The best photocatalytic activity was observed for an optimized TiO2/GO weight mixing ratio of 7:11, with a reaction rate constant up to 0.067 min-1. The addition of GO into TiO2 enhances photocatalytic activity and adsorption of MB molecules. The synthetic reaction rate constant was up to approximately 0.11 min-1, which was also the highest among the catalysts. The microreactor exhibited good sensitivity and reproducibility without weakening the performance of the photocatalysts. Consequently, the photocatalytic microreactor is promising as a simple, portable, and rapid screening tool for new photocatalysts.

Holistic Context-Sensitivity for Run-Time Optimization of Flexible Manufacturing Systems.

PubMed

Scholze, Sebastian; Barata, Jose; Stokic, Dragan

2017-02-24

Highly flexible manufacturing systems require continuous run-time (self-) optimization of processes with respect to diverse parameters, e.g., efficiency, availability, energy consumption etc. A promising approach for achieving (self-) optimization in manufacturing systems is the usage of the context sensitivity approach based on data streaming from high amount of sensors and other data sources. Cyber-physical systems play an important role as sources of information to achieve context sensitivity. Cyber-physical systems can be seen as complex intelligent sensors providing data needed to identify the current context under which the manufacturing system is operating. In this paper, it is demonstrated how context sensitivity can be used to realize a holistic solution for (self-) optimization of discrete flexible manufacturing systems, by making use of cyber-physical systems integrated in manufacturing systems/processes. A generic approach for context sensitivity, based on self-learning algorithms, is proposed aiming at a various manufacturing systems. The new solution encompasses run-time context extractor and optimizer. Based on the self-learning module both context extraction and optimizer are continuously learning and improving their performance. The solution is following Service Oriented Architecture principles. The generic solution is developed and then applied to two very different manufacturing processes.

Holistic Context-Sensitivity for Run-Time Optimization of Flexible Manufacturing Systems

PubMed Central

Scholze, Sebastian; Barata, Jose; Stokic, Dragan

2017-01-01

Highly flexible manufacturing systems require continuous run-time (self-) optimization of processes with respect to diverse parameters, e.g., efficiency, availability, energy consumption etc. A promising approach for achieving (self-) optimization in manufacturing systems is the usage of the context sensitivity approach based on data streaming from high amount of sensors and other data sources. Cyber-physical systems play an important role as sources of information to achieve context sensitivity. Cyber-physical systems can be seen as complex intelligent sensors providing data needed to identify the current context under which the manufacturing system is operating. In this paper, it is demonstrated how context sensitivity can be used to realize a holistic solution for (self-) optimization of discrete flexible manufacturing systems, by making use of cyber-physical systems integrated in manufacturing systems/processes. A generic approach for context sensitivity, based on self-learning algorithms, is proposed aiming at a various manufacturing systems. The new solution encompasses run-time context extractor and optimizer. Based on the self-learning module both context extraction and optimizer are continuously learning and improving their performance. The solution is following Service Oriented Architecture principles. The generic solution is developed and then applied to two very different manufacturing processes. PMID:28245564

Modular Bayesian Networks with Low-Power Wearable Sensors for Recognizing Eating Activities

PubMed Central

Kim, Kee-Hoon

2017-01-01

Recently, recognizing a user’s daily activity using a smartphone and wearable sensors has become a popular issue. However, in contrast with the ideal definition of an experiment, there could be numerous complex activities in real life with respect to its various background and contexts: time, space, age, culture, and so on. Recognizing these complex activities with limited low-power sensors, considering the power and memory constraints of the wearable environment and the user’s obtrusiveness at once is not an easy problem, although it is very crucial for the activity recognizer to be practically useful. In this paper, we recognize activity of eating, which is one of the most typical examples of a complex activity, using only daily low-power mobile and wearable sensors. To organize the related contexts systemically, we have constructed the context model based on activity theory and the “Five W’s”, and propose a Bayesian network with 88 nodes to predict uncertain contexts probabilistically. The structure of the proposed Bayesian network is designed by a modular and tree-structured approach to reduce the time complexity and increase the scalability. To evaluate the proposed method, we collected the data with 10 different activities from 25 volunteers of various ages, occupations, and jobs, and have obtained 79.71% accuracy, which outperforms other conventional classifiers by 7.54–14.4%. Analyses of the results showed that our probabilistic approach could also give approximate results even when one of contexts or sensor values has a very heterogeneous pattern or is missing. PMID:29232937

Optical mapping system with real-time control capability.

PubMed

Iravanian, Shahriar; Christini, David J

2007-10-01

Real-time, closed-loop intervention is an emerging experiment-control method that promises to provide invaluable new insight into cardiac electrophysiology. One example is the investigation of closed-loop feedback control of cardiac activity (e.g., alternans) as a possible method of preventing arrhythmia onset. To date, such methods have been investigated only in vitro using microelectrode systems, which are hindered by poor spatial resolution and are not well suited for atrial or ventricular tissue preparations. We have developed a system that uses optical mapping techniques and an electrical stimulator as the sensory and effector arms, respectively, of a closed-loop, real-time control system. The system consists of a 2,048 x 1 pixel line-scan charge-coupled device camera that records optical signals from the tissue. Custom-image processing and control software, which is implemented on top of a hard real-time operation system (RTAI Linux), process the data and make control decisions with a deterministic delay of <1 ms. The system is tested in two ways: 1) it is used to control, in real time, simulated optical signals of electrical alternans; and 2) it uses precisely timed, feedback-controlled initiation of antitachycardia pacing to terminate reentrant arrhythmias in an arterially perfused swine right ventricle stained with voltage-sensitive fluorescent dye 4{beta-[2-(di-n-butylamino)-6-napathy]vinyl}pyridinium (di-4-ANEPPS). Thus real-time control of cardiac activity using optical mapping techniques is feasible. Such a system is attractive because it offers greater measurement resolution than the electrode-based systems with which real-time control has been used previously.

Context Mining of Sedentary Behaviour for Promoting Self-Awareness Using a Smartphone.

PubMed

Fahim, Muhammad; Baker, Thar; Khattak, Asad Masood; Shah, Babar; Aleem, Saiqa; Chow, Francis

2018-03-15

Sedentary behaviour is increasing due to societal changes and is related to prolonged periods of sitting. There is sufficient evidence proving that sedentary behaviour has a negative impact on people's health and wellness. This paper presents our research findings on how to mine the temporal contexts of sedentary behaviour by utilizing the on-board sensors of a smartphone. We use the accelerometer sensor of the smartphone to recognize user situations (i.e., still or active). If our model confirms that the user context is still, then there is a high probability of being sedentary. Then, we process the environmental sound to recognize the micro-context, such as working on a computer or watching television during leisure time. Our goal is to reduce sedentary behaviour by suggesting preventive interventions to take short breaks during prolonged sitting to be more active. We achieve this goal by providing the visualization to the user, who wants to monitor his/her sedentary behaviour to reduce unhealthy routines for self-management purposes. The main contribution of this paper is two-fold: (i) an initial implementation of the proposed framework supporting real-time context identification; (ii) testing and evaluation of the framework, which suggest that our application is capable of substantially reducing sedentary behaviour and assisting users to be active.

Context-aware pattern discovery for moving object trajectories

NASA Astrophysics Data System (ADS)

Sharif, Mohammad; Asghar Alesheikh, Ali; Kaffash Charandabi, Neda

2018-05-01

Movement of point objects are highly sensitive to the underlying situations and conditions during the movement, which are known as contexts. Analyzing movement patterns, while accounting the contextual information, helps to better understand how point objects behave in various contexts and how contexts affect their trajectories. One potential solution for discovering moving objects patterns is analyzing the similarities of their trajectories. This article, therefore, contextualizes the similarity measure of trajectories by not only their spatial footprints but also a notion of internal and external contexts. The dynamic time warping (DTW) method is employed to assess the multi-dimensional similarities of trajectories. Then, the results of similarity searches are utilized in discovering the relative movement patterns of the moving point objects. Several experiments are conducted on real datasets that were obtained from commercial airplanes and the weather information during the flights. The results yielded the robustness of DTW method in quantifying the commonalities of trajectories and discovering movement patterns with 80 % accuracy. Moreover, the results revealed the importance of exploiting contextual information because it can enhance and restrict movements.

A Highly Sensitive Chemiluminometric Assay for Real-Time Detection of Biological Hydrogen Peroxide Formation.

PubMed

Zhu, Hong; Jia, Zhenquan; Trush, Michael A; Li, Y Robert

2016-05-01

Hydrogen peroxide (H 2 O 2 ) is a major reactive oxygen species (ROS) produced by various cellular sources, especially mitochondria. At high levels, H 2 O 2 causes oxidative stress, leading to cell injury, whereas at low concentrations, this ROS acts as an important second messenger to participate in cellular redox signaling. Detection and measurement of the levels or rates of production of cellular H 2 O 2 are instrumental in studying the biological effects of this major ROS. While a number of assays have been developed over the past decades for detecting and/or quantifying biological H 2 O 2 formation, none has been shown to be perfect. Perhaps there is no perfect assay for sensitively and accurately quantifying H 2 O 2 as well as other ROS in cells, wherein numerous potential reactants are present to interfere with the reliable measurement of the specific ROS. In this context, each assay has its own advantages and intrinsic limitations. This article describes a highly sensitive assay for real-time detection of H 2 O 2 formation in cultured cells and isolated mitochondria. This assay is based on the luminol/horseradish peroxidase-dependent chemiluminescence that is inhibitable by catalase. The article discusses the usefulness and shortcomings of this chemiluminometric assay in detecting biological H 2 O 2 formation induced by beta-lapachone redox cycling with both cells and isolated mitochondria.

Splicing variant profiles and single nucleotide polymorphisms of the glucocorticoid receptor gene in relation to glucocorticoid sensitivity of B-cell precursor acute lymphoblastic leukaemia.

PubMed

Huang, Meixian; Inukai, Takeshi; Kagami, Keiko; Abe, Masako; Shinohara, Tamao; Watanabe, Atsushi; Somazu, Shinpei; Oshiro, Hiroko; Goi, Kumiko; Goto, Hiroaki; Minegishi, Masayoshi; Iwamoto, Shotaro; Urayama, Kevin Y; Sugita, Kanji

2018-02-01

Glucocorticoid (GC) shows antileukaemic activity via binding to the GC receptor (GR). The human GR gene has 4 splicing variants besides the functional isoform GRα, but their significance in GC sensitivity of acute lymphoblastic leukaemia (ALL) has been inconsistent. Additionally, several studies evaluated the relevance of GR gene single nucleotide polymorphisms (SNPs) in the GC sensitivity of ALL, but the current cumulative evidence appears inconclusive. Addressing limitations in previous studies, we used a large series of B-cell precursor ALL (BCP-ALL) cell lines established from Japanese patients to comprehensively examine all 5 splicing variants of the GR gene and candidate SNPs, and their association with GC-sensitivity. We performed real-time reverse transcription polymerase chain reaction (RT-PCR) analyses with 10 sets of primers that differentially quantify the 5 isoforms in different combinations, and the strongest correlations with GC sensitivity were observed for the real-time RT-PCR of exons 7 and 8 (prednisolone sensitivity; r = -0.534, R 2  = 0.29, P = 1.4 × 10 -6 ) and exons 8 and 9a (r = -0.583, R 2  = 0.34, P = 7.6 × 10 -8 ), both specific for GRα and GRγ isoforms. In contrast, the real-time RT-PCR of junction of exons 3g and 4 and exon 4, specific for GRγ isoform alone, did not show significant correlation with GC sensitivity (prednisolone sensitivity; r = -0.403, R 2  = 0.16, P = 4.6 × 10 -4 ). These observations are consistent with the notion that GRα plays a central role in the GC-mediated proapoptotic activity in BCP-ALL. In addition, a promoter region SNP genotype (rs72555796) showed a significant association with GC sensitivity (prednisolone sensitivity; P = .010) and tended to show an association with GR gene expression (RT-PCR of exons 7 and 8; P = .170). These findings indicate that isoform profiles and SNP genotypes of the GR gene may be useful indicators of GC sensitivity in BCP-ALL. Copyright © 2017 John Wiley & Sons, Ltd.

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

PubMed

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

2012-09-01

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

How orchids concentrate? The relationship between physiological stress reactivity and cognitive performance during infancy and early childhood.

PubMed

Wass, Sam V

2018-03-30

The Autonomic Nervous System (ANS) is involved both in higher-order cognition such as attention and learning, and in responding to unexpected, threatening events. Increased ANS reactivity may confer both superior short-term cognitive performance, and heightened long-term susceptibility to adverse events. Here, we evaluate this hypothesis within the Differential Susceptibility Theory (DST) framework. We hypothesise that individuals with increased reactivity may show heightened biological sensitivity to context, conferring both positive (development-enhancing) effects (superior attention and learning) and negative (risk-promoting) effects (increased sensitivity to unsupportive environments). First, we examine how ANS reactivity relates to early cognitive performance. We hypothesise that increased phasic ANS reactivity, observed at lower tonic (pre-stimulus) ANS activity, is associated with better attention and learning. We conclude that the evidence is largely in support. Second we discuss whether ANS reactivity to 'positive', attention-eliciting and to 'negative', aversive stimuli is a one-dimensional construct; and evaluate evidence for how the real-world environment influences physiological stress over short and long time-frames. We identify three areas where the evidence is currently inconclusive. Copyright © 2018 Elsevier Ltd. All rights reserved.

Comparison of culture, single and multiplex real-time PCR for detection of Sabin poliovirus shedding in recently vaccinated Indian children.

PubMed

Giri, Sidhartha; Rajan, Anand K; Kumar, Nirmal; Dhanapal, Pavithra; Venkatesan, Jayalakshmi; Iturriza-Gomara, Miren; Taniuchi, Mami; John, Jacob; Abraham, Asha Mary; Kang, Gagandeep

2017-08-01

Although, culture is considered the gold standard for poliovirus detection from stool samples, real-time PCR has emerged as a faster and more sensitive alternative. Detection of poliovirus from the stool of recently vaccinated children by culture, single and multiplex real-time PCR was compared. Of the 80 samples tested, 55 (68.75%) were positive by culture compared to 61 (76.25%) and 60 (75%) samples by the single and one step multiplex real-time PCR assays respectively. Real-time PCR (singleplex and multiplex) is more sensitive than culture for poliovirus detection in stool, although the difference was not statistically significant. © 2017 Wiley Periodicals, Inc.

Dissociating linguistic and non-linguistic gesture processing: electrophysiological evidence from American Sign Language.

PubMed

Grosvald, Michael; Gutierrez, Eva; Hafer, Sarah; Corina, David

2012-04-01

A fundamental advance in our understanding of human language would come from a detailed account of how non-linguistic and linguistic manual actions are differentiated in real time by language users. To explore this issue, we targeted the N400, an ERP component known to be sensitive to semantic context. Deaf signers saw 120 American Sign Language sentences, each consisting of a "frame" (a sentence without the last word; e.g. BOY SLEEP IN HIS) followed by a "last item" belonging to one of four categories: a high-close-probability sign (a "semantically reasonable" completion to the sentence; e.g. BED), a low-close-probability sign (a real sign that is nonetheless a "semantically odd" completion to the sentence; e.g. LEMON), a pseudo-sign (phonologically legal but non-lexical form), or a non-linguistic grooming gesture (e.g. the performer scratching her face). We found significant N400-like responses in the incongruent and pseudo-sign contexts, while the gestures elicited a large positivity. Copyright © 2012 Elsevier Inc. All rights reserved.

Dissociating linguistic and non-linguistic gesture processing: Electrophysiological evidence from American Sign Language

PubMed Central

Grosvald, Michael; Gutierrez, Eva; Hafer, Sarah; Corina, David

2012-01-01

A fundamental advance in our understanding of human language would come from a detailed account of how non-linguistic and linguistic manual actions are differentiated in real time by language users. To explore this issue, we targeted the N400, an ERP component known to be sensitive to semantic context. Deaf signers saw 120 American Sign Language sentences, each consisting of a “frame” (a sentence without the last word; e.g. BOY SLEEP IN HIS) followed by a “last item” belonging to one of four categories: a high-cloze-probability sign (a “semantically reasonable” completion to the sentence; e.g. BED), a low-cloze-probability sign (a real sign that is nonetheless a “semantically odd” completion to the sentence; e.g. LEMON), a pseudo-sign (phonologically legal but non-lexical form), or a non-linguistic grooming gesture (e.g. the performer scratching her face). We found significant N400-like responses in the incongruent and pseudo-sign contexts, while the gestures elicited a large positivity. PMID:22341555

CAreDroid: Adaptation Framework for Android Context-Aware Applications

PubMed Central

Elmalaki, Salma; Wanner, Lucas; Srivastava, Mani

2015-01-01

Context-awareness is the ability of software systems to sense and adapt to their physical environment. Many contemporary mobile applications adapt to changing locations, connectivity states, available computational and energy resources, and proximity to other users and devices. Nevertheless, there is little systematic support for context-awareness in contemporary mobile operating systems. Because of this, application developers must build their own context-awareness adaptation engines, dealing directly with sensors and polluting application code with complex adaptation decisions. In this paper, we introduce CAreDroid, which is a framework that is designed to decouple the application logic from the complex adaptation decisions in Android context-aware applications. In this framework, developers are required— only—to focus on the application logic by providing a list of methods that are sensitive to certain contexts along with the permissible operating ranges under those contexts. At run time, CAreDroid monitors the context of the physical environment and intercepts calls to sensitive methods, activating only the blocks of code that best fit the current physical context. CAreDroid is implemented as part of the Android runtime system. By pushing context monitoring and adaptation into the runtime system, CAreDroid eases the development of context-aware applications and increases their efficiency. In particular, case study applications implemented using CAre-Droid are shown to have: (1) at least half lines of code fewer and (2) at least 10× more efficient in execution time compared to equivalent context-aware applications that use only standard Android APIs. PMID:26834512

CAreDroid: Adaptation Framework for Android Context-Aware Applications.

PubMed

Elmalaki, Salma; Wanner, Lucas; Srivastava, Mani

2015-09-01

Context-awareness is the ability of software systems to sense and adapt to their physical environment. Many contemporary mobile applications adapt to changing locations, connectivity states, available computational and energy resources, and proximity to other users and devices. Nevertheless, there is little systematic support for context-awareness in contemporary mobile operating systems. Because of this, application developers must build their own context-awareness adaptation engines, dealing directly with sensors and polluting application code with complex adaptation decisions. In this paper, we introduce CAreDroid, which is a framework that is designed to decouple the application logic from the complex adaptation decisions in Android context-aware applications. In this framework, developers are required- only-to focus on the application logic by providing a list of methods that are sensitive to certain contexts along with the permissible operating ranges under those contexts. At run time, CAreDroid monitors the context of the physical environment and intercepts calls to sensitive methods, activating only the blocks of code that best fit the current physical context. CAreDroid is implemented as part of the Android runtime system. By pushing context monitoring and adaptation into the runtime system, CAreDroid eases the development of context-aware applications and increases their efficiency. In particular, case study applications implemented using CAre-Droid are shown to have: (1) at least half lines of code fewer and (2) at least 10× more efficient in execution time compared to equivalent context-aware applications that use only standard Android APIs.

A Novel Fiber Optic Based Surveillance System for Prevention of Pipeline Integrity Threats.

PubMed

Tejedor, Javier; Macias-Guarasa, Javier; Martins, Hugo F; Piote, Daniel; Pastor-Graells, Juan; Martin-Lopez, Sonia; Corredera, Pedro; Gonzalez-Herraez, Miguel

2017-02-12

This paper presents a novel surveillance system aimed at the detection and classification of threats in the vicinity of a long gas pipeline. The sensing system is based on phase-sensitive optical time domain reflectometry ( ϕ -OTDR) technology for signal acquisition and pattern recognition strategies for threat identification. The proposal incorporates contextual information at the feature level and applies a system combination strategy for pattern classification. The contextual information at the feature level is based on the tandem approach (using feature representations produced by discriminatively-trained multi-layer perceptrons) by employing feature vectors that spread different temporal contexts. The system combination strategy is based on a posterior combination of likelihoods computed from different pattern classification processes. The system operates in two different modes: (1) machine + activity identification, which recognizes the activity being carried out by a certain machine, and (2) threat detection, aimed at detecting threats no matter what the real activity being conducted is. In comparison with a previous system based on the same rigorous experimental setup, the results show that the system combination from the contextual feature information improves the results for each individual class in both operational modes, as well as the overall classification accuracy, with statistically-significant improvements.

Separate neural mechanisms underlie choices and strategic preferences in risky decision making.

PubMed

Venkatraman, Vinod; Payne, John W; Bettman, James R; Luce, Mary Frances; Huettel, Scott A

2009-05-28

Adaptive decision making in real-world contexts often relies on strategic simplifications of decision problems. Yet, the neural mechanisms that shape these strategies and their implementation remain largely unknown. Using an economic decision-making task, we dissociate brain regions that predict specific choices from those predicting an individual's preferred strategy. Choices that maximized gains or minimized losses were predicted by functional magnetic resonance imaging activation in ventromedial prefrontal cortex or anterior insula, respectively. However, choices that followed a simplifying strategy (i.e., attending to overall probability of winning) were associated with activation in parietal and lateral prefrontal cortices. Dorsomedial prefrontal cortex, through differential functional connectivity with parietal and insular cortex, predicted individual variability in strategic preferences. Finally, we demonstrate that robust decision strategies follow from neural sensitivity to rewards. We conclude that decision making reflects more than compensatory interaction of choice-related regions; in addition, specific brain systems potentiate choices depending on strategies, traits, and context.

Separate neural mechanisms underlie choices and strategic preferences in risky decision making

PubMed Central

Venkatraman, Vinod; Payne, John W.; Bettman, James R.; Luce, Mary Frances; Huettel, Scott A.

2011-01-01

Adaptive decision making in real-world contexts often relies on strategic simplifications of decision problems. Yet, the neural mechanisms that shape these strategies and their implementation remain largely unknown. Using a novel economic decision-making task, we dissociate brain regions that predict specific choices from those predicting an individual’s preferred strategy. Choices that maximized gains or minimized losses were predicted by fMRI activation in ventromedial prefrontal cortex or anterior insula, respectively. However, choices that followed a simplifying strategy (i.e., attending to overall probability of winning) were associated with activation in parietal and lateral prefrontal cortices. Dorsomedial prefrontal cortex, through differential functional connectivity with parietal and insular cortex, predicted individual variability in strategic preferences. Finally, we demonstrate that robust decision strategies follow from neural sensitivity to rewards. We conclude that decision making reflects more than compensatory interaction of choice-related regions; in addition, specific brain systems potentiate choices depending upon strategies, traits, and context. PMID:19477159

The Abbott RealTime High Risk HPV test is a clinically validated human papillomavirus assay for triage in the referral population and use in primary cervical cancer screening in women 30 years and older: a review of validation studies.

PubMed

Poljak, Mario; Oštrbenk, Anja

2013-01-01

Human papillomavirus (HPV) testing has become an essential part of current clinical practice in the management of cervical cancer and precancerous lesions. We reviewed the most important validation studies of a next-generation real-time polymerase chain reaction-based assay, the RealTime High Risk HPV test (RealTime)(Abbott Molecular, Des Plaines, IL, USA), for triage in referral population settings and for use in primary cervical cancer screening in women 30 years and older published in peer-reviewed journals from 2009 to 2013. RealTime is designed to detect 14 high-risk HPV genotypes with concurrent distinction of HPV-16 and HPV-18 from 12 other HPV genotypes. The test was launched on the European market in January 2009 and is currently used in many laboratories worldwide for routine detection of HPV. We concisely reviewed validation studies of a next-generation real-time polymerase chain reaction (PCR)-based assay: the Abbott RealTime High Risk HPV test. Eight validation studies of RealTime in referral settings showed its consistently high absolute clinical sensitivity for both CIN2+ (range 88.3-100%) and CIN3+ (range 93.0-100%), as well as comparative clinical sensitivity relative to the currently most widely used HPV test: the Qiagen/Digene Hybrid Capture 2 HPV DNA Test (HC2). Due to the significantly different composition of the referral populations, RealTime absolute clinical specificity for CIN2+ and CIN3+ varied greatly across studies, but was comparable relative to HC2. Four validation studies of RealTime performance in cervical cancer screening settings showed its consistently high absolute clinical sensitivity for both CIN2+ and CIN3+, as well as comparative clinical sensitivity and specificity relative to HC2 and GP5+/6+ PCR. RealTime has been extensively evaluated in the last 4 years. RealTime can be considered clinically validated for triage in referral population settings and for use in primary cervical cancer screening in women 30 years and older.

Experiential and authentic learning approaches in vaccine management.

PubMed

Kartoglu, Umit; Vesper, James; Teräs, Hanna; Reeves, Thomas

2017-04-19

A high level of concern is placed on the storage, handling, transportation, and distribution of vaccines and other pharmaceutical products, particularly those that are time and temperature sensitive. While active and passive cooling equipment and monitoring devices are important, it is the various personnel responsible for executing and writing procedures, designing and operating systems, and investigating problems and helping prevent them who are paramount in establishing and maintaining a "cold chain" for time and temperature sensitive pharmaceutical products (TTSPPs). These professionals must possess the required competencies, knowledge, skills and abilities so they can effectively perform these activities with appropriate levels of expertise. These are complex tasks that require the development of higher cognitive skills that cannot be adequately addressed through professional development opportunities based on simple information delivery and content acquisition. This paper describes two unique learning solutions (one on a bus called the "wheels course" and the other online called "e-learning") that have been developed by WHO Global Learning Opportunities (WHO/GLO) to provide participants with opportunities not just to learn about cold chain systems or vaccine management, but, rather, to develop high levels of expertise in their respective fields through experiential and authentic learning activities. In these interactive learning environments, participants have opportunities to address real-life situations in contexts similar to what they may face in their own work environments and develop solutions and critical thinking skills they can apply when they return to their jobs. This paper further delineates the managerial and operational vaccine management functions encompassed in these two unique learning environments. The paper also describes the alignment of the objectives addressed in the "wheels course" and the e-learning version with effective vaccine management (EVM) criteria as prescribed by WHO. The paper concludes with an example of a real world product developed by course graduates (specifically a decision tree that is now used by some national programmes). These types of products, valuable in their own right, often emerge when learning environments based on authentic learning principles are designed and implemented as they were by WHO/GLO. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

The real deal: Willingness-to-pay and satiety expectations are greater for real foods versus their images.

PubMed

Romero, Carissa A; Compton, Michael T; Yang, Yueran; Snow, Jacqueline C

2017-11-23

Laboratory studies of human dietary choice have relied on computerized two-dimensional (2D) images as stimuli, whereas in everyday life, consumers make decisions in the context of real foods that have actual caloric content and afford grasping and consumption. Surprisingly, few studies have compared whether real foods are valued more than 2D images of foods, and in the studies that have, differences in the stimuli and testing conditions could have resulted in inflated bids for the real foods. Moreover, although the caloric content of food images has been shown to influence valuation, no studies to date have investigated whether 'real food exposure effects' on valuation reflect greater sensitivity to the caloric content of real foods versus images. Here, we compared willingness-to-pay (WTP) for, and expectations about satiety after consuming, everyday snack foods that were displayed as real foods versus 2D images. Critically, our 2D images were matched closely to the real foods for size, background, illumination, and apparent distance, and trial presentation and stimulus timing were identical across conditions. We used linear mixed effects modeling to determine whether effects of display format were modulated by food preference and the caloric content of the foods. Compared to food images, observers were willing to pay 6.62% more for (Experiment 1) and believed that they would feel more satiated after consuming (Experiment 2), foods displayed as real objects. Moreover, these effects appeared to be consistent across food preference, caloric content, as well as observers' estimates of the caloric content of the foods. Together, our results confirm that consumers' perception and valuation of everyday foods is influenced by the format in which they are displayed. Our findings raise important new insights into the factors that shape dietary choice in real-world contexts and highlight potential avenues for improving public health approaches to diet and obesity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Use of Referential Discourse Contexts in L2 Offline and Online Sentence Processing.

PubMed

Yang, Pi-Lan

2016-10-01

The present study aimed to investigate (a) the extent to which Chinese-speaking learners of English in Taiwan use referential noun phrase (NP) information contained in discourse contexts to complete ambiguous noun/verb fragments in a sentence completion task, and (b) whether and when they use the contexts to disambiguate main verb versus reduced relative clause (MV/RRC) ambiguities in real time. Results showed that unlike native English speakers, English learners did not create a marked increase in RRC completions in biasing two-NP-referent discourse contexts except for advanced learners. Nevertheless, like native speakers, the learners at elementary, intermediate, and advanced English proficiency levels all used the information in a later stage of resolving the MV/RRC ambiguities in real time. The delayed effect of referential context information observed suggests that L2 learners, like native speakers, are able to construct syntax-to-discourse mappings in real time. It also suggests that processing of syntactic information takes precedence over integration of syntactic information with discourse information during L1 and L2 online sentence processing.

Analytical and clinical performance characteristics of the Abbott RealTime MTB RIF/INH Resistance, an assay for the detection of rifampicin and isoniazid resistant Mycobacterium tuberculosis in pulmonary specimens.

PubMed

Kostera, Joshua; Leckie, Gregor; Tang, Ning; Lampinen, John; Szostak, Magdalena; Abravaya, Klara; Wang, Hong

2016-12-01

Clinical management of drug-resistant tuberculosis patients continues to present significant challenges to global health. To tackle these challenges, the Abbott RealTime MTB RIF/INH Resistance assay was developed to accelerate the diagnosis of rifampicin and/or isoniazid resistant tuberculosis to within a day. This article summarizes the performance of the Abbott RealTime MTB RIF/INH Resistance assay; including reliability, analytical sensitivity, and clinical sensitivity/specificity as compared to Cepheid GeneXpert MTB/RIF version 1.0 and Hain MTBDRplus version 2.0. The limit of detection (LOD) of the Abbott RealTime MTB RIF/INH Resistance assay was determined to be 32 colony forming units/milliliter (cfu/mL) using the Mycobacterium tuberculosis (MTB) strain H37Rv cell line. For rifampicin resistance detection, the Abbott RealTime MTB RIF/INH Resistance assay demonstrated statistically equivalent clinical sensitivity and specificity as compared to Cepheid GeneXpert MTB/RIF. For isoniazid resistance detection, the assay demonstrated statistically equivalent clinical sensitivity and specificity as compared to Hain MTBDRplus. The performance data presented herein demonstrate that the Abbott RealTime MTB RIF/INH Resistance assay is a sensitive, robust, and reliable test for realtime simultaneous detection of first line anti-tuberculosis antibiotics rifampicin and isoniazid in patient specimens. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.

Effects of reward context on feedback processing as indexed by time-frequency analysis.

PubMed

Watts, Adreanna T M; Bernat, Edward M

2018-05-11

The role of reward context has been investigated as an important factor in feedback processing. Previous work has demonstrated that the amplitude of the feedback negativity (FN) depends on the value of the outcome relative to the range of possible outcomes in a given context, not the objective value of the outcome. However, some research has shown that the FN does not scale with loss magnitude in loss-only contexts, suggesting that some contexts do not show a pattern of context dependence. Methodologically, time-frequency decomposition techniques have proven useful for isolating time-domain ERP activity as separable processes indexed in delta (< 3 Hz) and theta (3-7 Hz). Thus, the current study assessed the role of context in a modified gambling feedback task using time-frequency analysis to better isolate the underlying processes. Results revealed that theta was more context dependent and reflected a binary evaluation of bad versus good outcomes in the gain and even contexts. Delta was more context independent: good outcomes scaled linearly with reward magnitude and good-bad differences scaled with context valence. Our findings reveal that theta and delta are differentially sensitive to context and that context valence may play a critical role in determining how the brain processes feedback. © 2018 Society for Psychophysiological Research.

Attractor States in Teaching and Learning Processes: A Study of Out-of-School Science Education.

PubMed

Geveke, Carla H; Steenbeek, Henderien W; Doornenbal, Jeannette M; Van Geert, Paul L C

2017-01-01

In order for out-of-school science activities that take place during school hours but outside the school context to be successful, instructors must have sufficient pedagogical content knowledge (PCK) to guarantee high-quality teaching and learning. We argue that PCK is a quality of the instructor-pupil system that is constructed in real-time interaction. When PCK is evident in real-time interaction, we define it as Expressed Pedagogical Content Knowledge (EPCK). The aim of this study is to empirically explore whether EPCK shows a systematic pattern of variation, and if so whether the pattern occurs in recurrent and temporary stable attractor states as predicted in the complex dynamic systems theory. This study concerned nine out-of-school activities in which pupils of upper primary school classes participated. A multivariate coding scheme was used to capture EPCK in real time. A principal component analysis of the time series of all the variables reduced the number of components. A cluster revealed general descriptions of the components across all cases. Cluster analyses of individual cases divided the time series into sequences, revealing High-, Low-, and Non-EPCK states. High-EPCK attractor states emerged at particular moments during activities, rather than being present all the time. Such High-EPCK attractor states were only found in a few cases, namely those where the pupils were prepared for the visit and the instructors were trained.

Simultaneous detection of papaya ringspot virus, papaya leaf distortion mosaic virus, and papaya mosaic virus by multiplex real-time reverse transcription PCR.

PubMed

Huo, P; Shen, W T; Yan, P; Tuo, D C; Li, X Y; Zhou, P

2015-12-01

Both the single infection of papaya ringspot virus (PRSV), papaya leaf distortion mosaic virus (PLDMV) or papaya mosaic virus (PapMV) and double infection of PRSV and PLDMV or PapMV which cause indistinguishable symptoms, threaten the papaya industry in Hainan Island, China. In this study, a multiplex real-time reverse transcription PCR (RT-PCR) was developed to detect simultaneously the three viruses based on their distinctive melting temperatures (Tms): 81.0±0.8°C for PRSV, 84.7±0.6°C for PLDMV, and 88.7±0.4°C for PapMV. The multiplex real-time RT-PCR method was specific and sensitive in detecting the three viruses, with a detection limit of 1.0×10(1), 1.0×10(2), and 1.0×10(2) copies for PRSV, PLDMV, and PapMV, respectively. Indeed, the reaction was 100 times more sensitive than the multiplex RT-PCR for PRSV, and 10 times more sensitive than multiplex RT-PCR for PLDMV. Field application of the multiplex real-time RT-PCR demonstrated that some non-symptomatic samples were positive for PLDMV by multiplex real-time RT-PCR but negative by multiplex RT-PCR, whereas some samples were positive for both PRSV and PLDMV by multiplex real-time RT-PCR assay but only positive for PLDMV by multiplex RT-PCR. Therefore, this multiplex real-time RT-PCR assay provides a more rapid, sensitive and reliable method for simultaneous detection of PRSV, PLDMV, PapMV and their mixed infections in papaya.

A Framework to Improve Energy Efficient Behaviour at Home through Activity and Context Monitoring

PubMed Central

García, Óscar; Alonso, Ricardo S.; Corchado, Juan M.

2017-01-01

Real-time Localization Systems have been postulated as one of the most appropriated technologies for the development of applications that provide customized services. These systems provide us with the ability to locate and trace users and, among other features, they help identify behavioural patterns and habits. Moreover, the implementation of policies that will foster energy saving in homes is a complex task that involves the use of this type of systems. Although there are multiple proposals in this area, the implementation of frameworks that combine technologies and use Social Computing to influence user behaviour have not yet reached any significant savings in terms of energy. In this work, the CAFCLA framework (Context-Aware Framework for Collaborative Learning Applications) is used to develop a recommendation system for home users. The proposed system integrates a Real-Time Localization System and Wireless Sensor Networks, making it possible to develop applications that work under the umbrella of Social Computing. The implementation of an experimental use case aided efficient energy use, achieving savings of 17%. Moreover, the conducted case study pointed to the possibility of attaining good energy consumption habits in the long term. This can be done thanks to the system’s real time and historical localization, tracking and contextual data, based on which customized recommendations are generated. PMID:28758987

Towards sensitive, high-throughput, biomolecular assays based on fluorescence lifetime

NASA Astrophysics Data System (ADS)

Ioanna Skilitsi, Anastasia; Turko, Timothé; Cianfarani, Damien; Barre, Sophie; Uhring, Wilfried; Hassiepen, Ulrich; Léonard, Jérémie

2017-09-01

Time-resolved fluorescence detection for robust sensing of biomolecular interactions is developed by implementing time-correlated single photon counting in high-throughput conditions. Droplet microfluidics is used as a promising platform for the very fast handling of low-volume samples. We illustrate the potential of this very sensitive and cost-effective technology in the context of an enzymatic activity assay based on fluorescently-labeled biomolecules. Fluorescence lifetime detection by time-correlated single photon counting is shown to enable reliable discrimination between positive and negative control samples at a throughput as high as several hundred samples per second.

Physical environment virtualization for human activities recognition

NASA Astrophysics Data System (ADS)

Poshtkar, Azin; Elangovan, Vinayak; Shirkhodaie, Amir; Chan, Alex; Hu, Shuowen

2015-05-01

Human activity recognition research relies heavily on extensive datasets to verify and validate performance of activity recognition algorithms. However, obtaining real datasets are expensive and highly time consuming. A physics-based virtual simulation can accelerate the development of context based human activity recognition algorithms and techniques by generating relevant training and testing videos simulating diverse operational scenarios. In this paper, we discuss in detail the requisite capabilities of a virtual environment to aid as a test bed for evaluating and enhancing activity recognition algorithms. To demonstrate the numerous advantages of virtual environment development, a newly developed virtual environment simulation modeling (VESM) environment is presented here to generate calibrated multisource imagery datasets suitable for development and testing of recognition algorithms for context-based human activities. The VESM environment serves as a versatile test bed to generate a vast amount of realistic data for training and testing of sensor processing algorithms. To demonstrate the effectiveness of VESM environment, we present various simulated scenarios and processed results to infer proper semantic annotations from the high fidelity imagery data for human-vehicle activity recognition under different operational contexts.

Taqman real-time quantitative PCR for identification of western flower thrip (Frankliniella occidentalis) for plant quarantine

PubMed Central

Huang, K. S.; Lee, S. E.; Yeh, Y.; Shen, G. S.; Mei, E.; Chang, C. M.

2010-01-01

Western flower thrip (Frankliniella occidentalis) is a major global pest of agricultural products. It directly damages crops through feeding, oviposition activity or transmission of several plant viruses. We describe a Taqman real-time quantitative PCR detection system, which can rapidly identify F. occidentalis from thrips larvae to complement the traditional morphological identification. The data showed that our detection system targeted on the ribosomal RNA gene regions of F. occidentalis has high sensitivity and specificity. The rapid method can be used for on-site testing of samples at ports-of-entry in the future. PMID:20129946

Taqman real-time quantitative PCR for identification of western flower thrip (Frankliniella occidentalis) for plant quarantine.

PubMed

Huang, K S; Lee, S E; Yeh, Y; Shen, G S; Mei, E; Chang, C M

2010-08-23

Western flower thrip (Frankliniella occidentalis) is a major global pest of agricultural products. It directly damages crops through feeding, oviposition activity or transmission of several plant viruses. We describe a Taqman real-time quantitative PCR detection system, which can rapidly identify F. occidentalis from thrips larvae to complement the traditional morphological identification. The data showed that our detection system targeted on the ribosomal RNA gene regions of F. occidentalis has high sensitivity and specificity. The rapid method can be used for on-site testing of samples at ports-of-entry in the future.

A novel duplex real time quantitative reverse transcription polymerase chain reaction for rubella virus with armored RNA as a noncompetitive internal positive control.

PubMed

Zhao, Lihong; Li, Ruiying; Liu, Aihua; Zhao, Shuping

2015-07-01

The objective of this study was to build and apply a duplex real time quantitative reverse transcription-polymerase chain reaction (RT-PCR) for rubella virus. Firstly, a 60-bp-long armored RV RNA was constructed in the laboratory. Secondly, a duplex real time RT-PCR assay was established. Thirdly, the 60-bp-long armored RV RNA was used as an internal positive control (IPC) for the duplex real time RT-PCR. And finally the duplex real time RT-PCR assay was applied to detect RV RNA in clinical specimens. The in-house assay has a high amplification efficiency (0.99), a high analytical sensitivity (200 copies/mL), and a good reproducibility. The diagnostic specificity and sensitivity of the in-house assay were both 100%, due to the monitoring of the armored RV RNA IPC. Therefore, the in-house duplex real time quantitative RT-PCR assay is a specific, sensitive, reproducible and accurate assay for quantitation of RV RNA in clinical specimens. And noncompetitive armored RV RNA IPC can monitor RT-PCR inhibition and prevent false-negative and inaccurate results in the real time detection system. Copyright © 2015 Elsevier B.V. All rights reserved.

Feasibility of real-time location systems in monitoring recovery after major abdominal surgery.

PubMed

Dorrell, Robert D; Vermillion, Sarah A; Clark, Clancy J

2017-12-01

Early mobilization after major abdominal surgery decreases postoperative complications and length of stay, and has become a key component of enhanced recovery pathways. However, objective measures of patient movement after surgery are limited. Real-time location systems (RTLS), typically used for asset tracking, provide a novel approach to monitoring in-hospital patient activity. The current study investigates the feasibility of using RTLS to objectively track postoperative patient mobilization. The real-time location system employs a meshed network of infrared and RFID sensors and detectors that sample device locations every 3 s resulting in over 1 million data points per day. RTLS tracking was evaluated systematically in three phases: (1) sensitivity and specificity of the tracking device using simulated patient scenarios, (2) retrospective passive movement analysis of patient-linked equipment, and (3) prospective observational analysis of a patient-attached tracking device. RTLS tracking detected a simulated movement out of a room with sensitivity of 91% and specificity 100%. Specificity decreased to 75% if time out of room was less than 3 min. All RTLS-tagged patient-linked equipment was identified for 18 patients, but measurable patient movement associated with equipment was detected for only 2 patients (11%) with 1-8 out-of-room walks per day. Ten patients were prospectively monitored using RTLS badges following major abdominal surgery. Patient movement was recorded using patient diaries, direct observation, and an accelerometer. Sensitivity and specificity of RTLS patient tracking were both 100% in detecting out-of-room ambulation and correlated well with direct observation and patient-reported ambulation. Real-time location systems are a novel technology capable of objectively and accurately monitoring patient movement and provide an innovative approach to promoting early mobilization after surgery.

Active pain coping is associated with the response in real-time fMRI neurofeedback during pain.

PubMed

Emmert, Kirsten; Breimhorst, Markus; Bauermann, Thomas; Birklein, Frank; Rebhorn, Cora; Van De Ville, Dimitri; Haller, Sven

2017-06-01

Real-time functional magnetic resonance imaging (rt-fMRI) neurofeedback is used as a tool to gain voluntary control of activity in various brain regions. Little emphasis has been put on the influence of cognitive and personality traits on neurofeedback efficacy and baseline activity. Here, we assessed the effect of individual pain coping on rt-fMRI neurofeedback during heat-induced pain. Twenty-eight healthy subjects completed the Coping Strategies Questionnaire (CSQ) prior to scanning. The first part of the fMRI experiment identified target regions using painful heat stimulation. Then, subjects were asked to down-regulate the pain target brain region during four neurofeedback runs with painful heat stimulation. Functional MRI analysis included correlation analysis between fMRI activation and pain ratings as well as CSQ ratings. At the behavioral level, the active pain coping (first principal component of CSQ) was correlated with pain ratings during neurofeedback. Concerning neuroimaging, pain sensitive regions were negatively correlated with pain coping. During neurofeedback, the pain coping was positively correlated with activation in the anterior cingulate cortex, prefrontal cortex, hippocampus and visual cortex. Thermode temperature was negatively correlated with anterior insula and dorsolateral prefrontal cortex activation. In conclusion, self-reported pain coping mechanisms and pain sensitivity are a source of variance during rt-fMRI neurofeedback possibly explaining variations in regulation success. In particular, active coping seems to be associated with successful pain regulation.

Mining Context-Aware Association Rules Using Grammar-Based Genetic Programming.

PubMed

Luna, Jose Maria; Pechenizkiy, Mykola; Del Jesus, Maria Jose; Ventura, Sebastian

2017-09-25

Real-world data usually comprise features whose interpretation depends on some contextual information. Such contextual-sensitive features and patterns are of high interest to be discovered and analyzed in order to obtain the right meaning. This paper formulates the problem of mining context-aware association rules, which refers to the search for associations between itemsets such that the strength of their implication depends on a contextual feature. For the discovery of this type of associations, a model that restricts the search space and includes syntax constraints by means of a grammar-based genetic programming methodology is proposed. Grammars can be considered as a useful way of introducing subjective knowledge to the pattern mining process as they are highly related to the background knowledge of the user. The performance and usefulness of the proposed approach is examined by considering synthetically generated datasets. A posteriori analysis on different domains is also carried out to demonstrate the utility of this kind of associations. For example, in educational domains, it is essential to identify and understand contextual and context-sensitive factors that affect overall and individual student behavior and performance. The results of the experiments suggest that the approach is feasible and it automatically identifies interesting context-aware associations from real-world datasets.

Pathomimetic cancer avatars for live-cell imaging of protease activity

PubMed Central

Ji, Kyungmin; Heyza, Joshua; Cavallo-Medved, Dora; Sloane, Bonnie F.

2016-01-01

Proteases are essential for normal physiology as well as multiple diseases, e.g., playing a causative role in cancer progression, including in tumor angiogenesis, invasion, and metastasis. Identification of dynamic alterations in protease activity may allow us to detect early stage cancers and to assess the efficacy of anti-cancer therapies. Despite the clinical importance of proteases in cancer progression, their functional roles individually and within the context of complex protease networks have not yet been well defined. These gaps in our understanding might be addressed with: 1) accurate and sensitive tools and methods to directly identify changes in protease activities in live cells, and 2) pathomimetic avatars for cancer that recapitulate in vitro the tumor in the context of its cellular and non-cellular microenvironment. Such avatars should be designed to facilitate mechanistic studies that can be translated to animal models and ultimately the clinic. Here, we will describe basic principles and recent applications of live-cell imaging for identification of active proteases. The avatars optimized by our laboratory are three-dimensional (3D) human breast cancer models in a matrix of reconstituted basement membrane (rBM). They are designated mammary architecture and microenvironment engineering (MAME) models as they have been designed to mimic the structural and functional interactions among cell types in the normal and cancerous human breast. We have demonstrated the usefulness of these pathomimetic avatars for following dynamic and temporal changes in cell:cell interactions and quantifying changes in protease activity associated with these interactions in real-time (4D). We also briefly describe adaptation of the avatars to custom-designed and fabricated tissue architecture and microenvironment engineering (TAME) chambers that enhance our ability to analyze concomitant changes in the malignant phenotype and the associated tumor microenvironment. PMID:26375517

Pathomimetic cancer avatars for live-cell imaging of protease activity.

PubMed

Ji, Kyungmin; Heyza, Joshua; Cavallo-Medved, Dora; Sloane, Bonnie F

2016-03-01

Proteases are essential for normal physiology as well as multiple diseases, e.g., playing a causative role in cancer progression, including in tumor angiogenesis, invasion, and metastasis. Identification of dynamic alterations in protease activity may allow us to detect early stage cancers and to assess the efficacy of anti-cancer therapies. Despite the clinical importance of proteases in cancer progression, their functional roles individually and within the context of complex protease networks have not yet been well defined. These gaps in our understanding might be addressed with: 1) accurate and sensitive tools and methods to directly identify changes in protease activities in live cells, and 2) pathomimetic avatars for cancer that recapitulate in vitro the tumor in the context of its cellular and non-cellular microenvironment. Such avatars should be designed to facilitate mechanistic studies that can be translated to animal models and ultimately the clinic. Here, we will describe basic principles and recent applications of live-cell imaging for identification of active proteases. The avatars optimized by our laboratory are three-dimensional (3D) human breast cancer models in a matrix of reconstituted basement membrane (rBM). They are designated mammary architecture and microenvironment engineering (MAME) models as they have been designed to mimic the structural and functional interactions among cell types in the normal and cancerous human breast. We have demonstrated the usefulness of these pathomimetic avatars for following dynamic and temporal changes in cell:cell interactions and quantifying changes in protease activity associated with these interactions in real-time (4D). We also briefly describe adaptation of the avatars to custom-designed and fabricated tissue architecture and microenvironment engineering (TAME) chambers that enhance our ability to analyze concomitant changes in the malignant phenotype and the associated tumor microenvironment. Copyright © 2015. Published by Elsevier B.V.

Interparental Conflict and Infants’ Behavior Problems: The Mediating Role of Maternal Sensitivity

PubMed Central

Zhou, Nan; Cao, Hongjian; Leerkes, Esther M.

2016-01-01

Although the negative effect of interparental conflict on child behavior problems has been well established, few studies have examined this association during infancy. This study examined the associations between mother-reported interparental conflict and young children’s behavior problems over the first two years of their lives in a sample of 212 mothers and infants. Two aspects of maternal sensitivity, sensitivity during distressing and nondistressing contexts, were examined as possible mediators between interparental conflict and infants’ behavior problems. Results indicated that interparental conflict was associated directly with infants’ externalizing problems over time, but was associated indirectly with infants’ internalizing problems over time via compromised maternal sensitivity within distressing contexts but not through maternal sensitivity within nondistressing contexts. No significant child gender differences were found. Such findings add to a limited body of research suggesting that the early interparental relationship context is relevant for infant adjustment. The salient mediating role of maternal sensitivity within distressing contexts provides important theoretical and practical insights for future studies. PMID:28114771

75 FR 2557 - Interim Policy for the Sharing of Information Collected by the Coast Guard Nationwide Automatic...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-15

... (real-time) information collected by the NAIS that is less than 12 hours from transmission. Level B... specific questions on the development of the NAIS final policy: 1. How might providing real-time, near real... collected by the NAIS considered sensitive? a. Is real-time or near real-time information collected by the...

32 CFR 644.8 - Planning and scheduling real estate activities.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Project Planning Civil Works § 644.8 Planning and scheduling... Memoranda; determination of final project boundaries; and preliminary real estate work to the point where... estate activities of the Corps are extremely sensitive, since they disrupt the lives of individuals and...

Polymeric LabChip Real-Time PCR as a Point-of-Care-Potential Diagnostic Tool for Rapid Detection of Influenza A/H1N1 Virus in Human Clinical Specimens

PubMed Central

Song, Hyun-Ok; Kim, Je-Hyoung; Ryu, Ho-Sun; Lee, Dong-Hoon; Kim, Sun-Jin; Kim, Deog-Joong; Suh, In Bum; Choi, Du Young; In, Kwang-Ho; Kim, Sung-Woo; Park, Hyun

2012-01-01

It is clinically important to be able to detect influenza A/H1N1 virus using a fast, portable, and accurate system that has high specificity and sensitivity. To achieve this goal, it is necessary to develop a highly specific primer set that recognizes only influenza A viral genes and a rapid real-time PCR system that can detect even a single copy of the viral gene. In this study, we developed and validated a novel fluidic chip-type real-time PCR (LabChip real-time PCR) system that is sensitive and specific for the detection of influenza A/H1N1, including the pandemic influenza strain A/H1N1 of 2009. This LabChip real-time PCR system has several remarkable features: (1) It allows rapid quantitative analysis, requiring only 15 min to perform 30 cycles of real-time PCR. (2) It is portable, with a weight of only 5.5 kg. (3) The reaction cost is low, since it uses disposable plastic chips. (4) Its high efficiency is equivalent to that of commercially available tube-type real-time PCR systems. The developed disposable LabChip is an economic, heat-transferable, light-transparent, and easy-to-fabricate polymeric chip compared to conventional silicon- or glass-based labchip. In addition, our LabChip has large surface-to-volume ratios in micro channels that are required for overcoming time consumed for temperature control during real-time PCR. The efficiency of the LabChip real-time PCR system was confirmed using novel primer sets specifically targeted to the hemagglutinin (HA) gene of influenza A/H1N1 and clinical specimens. Eighty-five human clinical swab samples were tested using the LabChip real-time PCR. The results demonstrated 100% sensitivity and specificity, showing 72 positive and 13 negative cases. These results were identical to those from a tube-type real-time PCR system. This indicates that the novel LabChip real-time PCR may be an ultra-fast, quantitative, point-of-care-potential diagnostic tool for influenza A/H1N1 with a high sensitivity and specificity. PMID:23285281

The LBT real-time based control software to mitigate and compensate vibrations

NASA Astrophysics Data System (ADS)

Borelli, J.; Trowitzsch, J.; Brix, M.; Kürster, M.; Gässler, W.; Bertram, T.; Briegel, F.

2010-07-01

The Large Binocular Telescope (LBT) uses two 8.4 meters active primary mirrors and two adaptive secondary mirrors on the same mounting to take advantage of its interferometric capabilities. Both applications, interferometry and AO, are sensitive to vibrations. Several measurement campaigns have been carried out at the LBT and their results strongly indicate that a vibration monitoring system is required to improve the performance of LINC-NIRVANA, LBTI, and ARGOS, the laser guided ground layer adaptive optic system. Currently, a control software for mitigation and compensation of the vibrations is being designed. A complex set of algorithms collects real-time vibration data, archiving it for further analysis, and in parallel, generating the tip-tilt and optical path difference (OPD) data for the control loop of the instruments. A real-time data acquisition device equipped with embedded real-time Linux is used in our systems. A set of quick-look tools is currently under development in order to verify if the conditions at the telescope are suitable for interferometric/adaptive observations.

Mobile Sensing and Support for People With Depression: A Pilot Trial in the Wild.

PubMed

Wahle, Fabian; Kowatsch, Tobias; Fleisch, Elgar; Rufer, Michael; Weidt, Steffi

2016-09-21

Depression is a burdensome, recurring mental health disorder with high prevalence. Even in developed countries, patients have to wait for several months to receive treatment. In many parts of the world there is only one mental health professional for over 200 people. Smartphones are ubiquitous and have a large complement of sensors that can potentially be useful in monitoring behavioral patterns that might be indicative of depressive symptoms and providing context-sensitive intervention support. The objective of this study is 2-fold, first to explore the detection of daily-life behavior based on sensor information to identify subjects with a clinically meaningful depression level, second to explore the potential of context sensitive intervention delivery to provide in-situ support for people with depressive symptoms. A total of 126 adults (age 20-57) were recruited to use the smartphone app Mobile Sensing and Support (MOSS), collecting context-sensitive sensor information and providing just-in-time interventions derived from cognitive behavior therapy. Real-time learning-systems were deployed to adapt to each subject's preferences to optimize recommendations with respect to time, location, and personal preference. Biweekly, participants were asked to complete a self-reported depression survey (PHQ-9) to track symptom progression. Wilcoxon tests were conducted to compare scores before and after intervention. Correlation analysis was used to test the relationship between adherence and change in PHQ-9. One hundred twenty features were constructed based on smartphone usage and sensors including accelerometer, Wifi, and global positioning systems (GPS). Machine-learning models used these features to infer behavior and context for PHQ-9 level prediction and tailored intervention delivery. A total of 36 subjects used MOSS for ≥2 weeks. For subjects with clinical depression (PHQ-9≥11) at baseline and adherence ≥8 weeks (n=12), a significant drop in PHQ-9 was observed (P=.01). This group showed a negative trend between adherence and change in PHQ-9 scores (rho=-.498, P=.099). Binary classification performance for biweekly PHQ-9 samples (n=143), with a cutoff of PHQ-9≥11, based on Random Forest and Support Vector Machine leave-one-out cross validation resulted in 60.1% and 59.1% accuracy, respectively. Proxies for social and physical behavior derived from smartphone sensor data was successfully deployed to deliver context-sensitive and personalized interventions to people with depressive symptoms. Subjects who used the app for an extended period of time showed significant reduction in self-reported symptom severity. Nonlinear classification models trained on features extracted from smartphone sensor data including Wifi, accelerometer, GPS, and phone use, demonstrated a proof of concept for the detection of depression superior to random classification. While findings of effectiveness must be reproduced in a RCT to proof causation, they pave the way for a new generation of digital health interventions leveraging smartphone sensors to provide context sensitive information for in-situ support and unobtrusive monitoring of critical mental health states.

Comparison of clinical and analytical performance of the Abbott Realtime High Risk HPV test to the performance of hybrid capture 2 in population-based cervical cancer screening.

PubMed

Poljak, Mario; Ostrbenk, Anja; Seme, Katja; Ucakar, Veronika; Hillemanns, Peter; Bokal, Eda Vrtacnik; Jancar, Nina; Klavs, Irena

2011-05-01

The clinical performance of the Abbott RealTime High Risk HPV (human papillomavirus) test (RealTime) and that of the Hybrid Capture 2 HPV DNA test (hc2) were prospectively compared in the population-based cervical cancer screening setting. In women >30 years old (n = 3,129), the clinical sensitivity of RealTime for detection of cervical intraepithelial neoplasia of grade 2 (CIN2) or worse (38 cases) and its clinical specificity for lesions of less than CIN2 (3,091 controls) were 100% and 93.3%, respectively, and those of hc2 were 97.4% and 91.8%, respectively. A noninferiority score test showed that the clinical specificity (P < 0.0001) and clinical sensitivity (P = 0.011) of RealTime were noninferior to those of hc2 at the recommended thresholds of 98% and 90%. In the total study population (women 20 to 64 years old; n = 4,432; 57 cases, 4,375 controls), the clinical sensitivity and specificity of RealTime were 98.2% and 89.5%, and those of hc2 were 94.7% and 87.7%, respectively. The analytical sensitivity and analytical specificity of RealTime in detecting targeted HPV types evaluated with the largest sample collection to date (4,479 samples) were 94.8% and 99.8%, and those of hc2 were 93.4% and 97.8%, respectively. Excellent analytical agreement between the two assays was obtained (kappa value, 0.84), while the analytical accuracy of RealTime was significantly higher than that of hc2. RealTime demonstrated high intralaboratory reproducibility and interlaboratory agreement with 500 samples retested 61 to 226 days after initial testing in two different laboratories. RealTime can be considered to be a reliable and robust HPV assay clinically comparable to hc2 for the detection of CIN2+ lesions in a population-based cervical cancer screening setting.

Diagnosis of invasive fungal infections using real-time PCR assay in paediatric acute leukaemia induction.

PubMed

Mandhaniya, Sushil; Iqbal, Sobuhi; Sharawat, Surender Kumar; Xess, Immaculata; Bakhshi, Sameer

2012-07-01

Invasive fungal infections (IFI) lead to morbidity and mortality in neutropenic patients and in allogenic stem cell transplantation. Serum-based fungal detection assays have limitation of specificity or sensitivity. Studies on fungal DNA detection using real-time PCR in childhood leukaemia are lacking. The aim of this study was to develop sensitive and specific diagnostic tools for IFI in paediatric acute leukaemia patients using real-time PCR. Of 100 randomised paediatric acute leukaemia patients receiving antifungal prophylaxis with voriconazole/amphotericin B, single peripheral whole blood sample in EDTA was used for Pan-AC real-time PCR assay (detects nine Candida and six Aspergillus species) in patients who failed prophylaxis due to proven, probable, possible or suspected fungal infections. PCR results were retrospectively correlated with clinical profile. Real-time PCR test was positive in 18/29 (62%) patients who failed prophylaxis. The only patient with proven IFI (mucormycosis), real-time PCR assay was negative. Real-time PCR was positive in 2/4 (50%) patients with possible and 16/24 (66.6%) suspected IFI and 5/10 (50%) patients with pneumonia. By applying method A/B, sensitivity and positive predictive value could not be commented due to unproven Aspergillus or Candida infections; specificity and negative predictive values (NPV) were 41% and 100% respectively; by method C (included episodes of possible IFI as true positive), sensitivity, specificity, PPV and NPV were 50%, 36%, 11% and 81% respectively. In those with suspected IFI, 8/24 (33.3%) were PCR negative and unnecessarily received empirical antifungal therapy (EAFT). Real-time PCR is a practical, rapid, non-invasive screening test for excluding IFI in paediatric leukaemia. The high NPV makes real-time PCR a promising tool to use this prior to initiating EAFT in antibiotic-resistant febrile neutropenic patients; this would avoid toxicity, cost and hospitalisation for EAFT (ClinicalTrials.gov identifier:NCT00624143). © 2011 Blackwell Verlag GmbH.

SGML Authoring Tools for Technical Communication.

ERIC Educational Resources Information Center

Davidson, W. J.

1993-01-01

Explains that structured authoring systems designed for the creation of generically encoded reusable information have context-sensitive application of markup, markup suppression, queing and automated formatting, structural navigation, and self-validation features. Maintains that they are a real alternative to conventional publishing systems. (SR)

Learning dictionaries of sparse codes of 3D movements of body joints for real-time human activity understanding.

PubMed

Qi, Jin; Yang, Zhiyong

2014-01-01

Real-time human activity recognition is essential for human-robot interactions for assisted healthy independent living. Most previous work in this area is performed on traditional two-dimensional (2D) videos and both global and local methods have been used. Since 2D videos are sensitive to changes of lighting condition, view angle, and scale, researchers begun to explore applications of 3D information in human activity understanding in recently years. Unfortunately, features that work well on 2D videos usually don't perform well on 3D videos and there is no consensus on what 3D features should be used. Here we propose a model of human activity recognition based on 3D movements of body joints. Our method has three steps, learning dictionaries of sparse codes of 3D movements of joints, sparse coding, and classification. In the first step, space-time volumes of 3D movements of body joints are obtained via dense sampling and independent component analysis is then performed to construct a dictionary of sparse codes for each activity. In the second step, the space-time volumes are projected to the dictionaries and a set of sparse histograms of the projection coefficients are constructed as feature representations of the activities. Finally, the sparse histograms are used as inputs to a support vector machine to recognize human activities. We tested this model on three databases of human activities and found that it outperforms the state-of-the-art algorithms. Thus, this model can be used for real-time human activity recognition in many applications.

Multi-Dimensional Pattern Discovery of Trajectories Using Contextual Information

NASA Astrophysics Data System (ADS)

Sharif, M.; Alesheikh, A. A.

2017-10-01

Movement of point objects are highly sensitive to the underlying situations and conditions during the movement, which are known as contexts. Analyzing movement patterns, while accounting the contextual information, helps to better understand how point objects behave in various contexts and how contexts affect their trajectories. One potential solution for discovering moving objects patterns is analyzing the similarities of their trajectories. This article, therefore, contextualizes the similarity measure of trajectories by not only their spatial footprints but also a notion of internal and external contexts. The dynamic time warping (DTW) method is employed to assess the multi-dimensional similarities of trajectories. Then, the results of similarity searches are utilized in discovering the relative movement patterns of the moving point objects. Several experiments are conducted on real datasets that were obtained from commercial airplanes and the weather information during the flights. The results yielded the robustness of DTW method in quantifying the commonalities of trajectories and discovering movement patterns with 80 % accuracy. Moreover, the results revealed the importance of exploiting contextual information because it can enhance and restrict movements.

Sex differences in daily life stress and craving in opioid-dependent patients.

PubMed

Moran, Landhing M; Kowalczyk, William J; Phillips, Karran A; Vahabzadeh, Massoud; Lin, Jia-Ling; Mezghanni, Mustapha; Epstein, David H; Preston, Kenzie L

2018-04-11

Responses to stress and drug craving differ between men and women. Differences in the momentary experience of stress in relation to craving are less well-understood. Using ecological momentary assessment (EMA), we examined sex differences in real-time in two areas: (1) causes and contexts associated with stress, and (2) the extent to which stress and drug cues are associated with craving. Outpatients on opioid-agonist treatment (135 males, 47 females) reported stress, craving, and behavior on smartphones for 16 weeks. They initiated an entry each time they felt more stressed than usual (stress event) and made randomly prompted entries 3 times/day. In stress-event entries, they identified the causes and context (location, activity, companions), and rated stress and craving severity. The causes reported for stress events did not differ significantly by sex. Women reported arguing and being in a store more often during stress events, and men reported working more often during stress events, compared to base rates (assessed via random prompts). Women showed a greater increase in opioid craving as a function of stress (p < 0.0001) and had higher stress ratings in the presence of both stress and drug cues relative to men (p < 0.01). Similar effects were found for cocaine craving in men (p < 0.0001). EMA methods provide evidence based on real-time activities and moods that opioid-dependent men and women experience similar contexts and causes for stress but differ in stress- and cue-induced craving. These findings support sex-based tailoring of treatment, but because not all participants conformed to the overall pattern of sex differences, any such tailoring should also consider person-level differences.

Digital Holography for in Situ Real-Time Measurement of Plasma-Facing-Component Erosion

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

ThomasJr., C. E.; Granstedt, E. M.; Biewer, Theodore M

2014-01-01

In situ, real time measurement of net plasma-facing-component (PFC) erosion/deposition in a real plasma device is challenging due to the need for good spatial and temporal resolution, sufficient sensitivity, and immunity to fringe-jump errors. Design of a high-sensitivity, potentially high-speed, dual-wavelength CO2 laser digital holography system (nominally immune to fringe jumps) for PFC erosion measurement is discussed.

Context sensitive solutions (CSS) online training course development.

DOT National Transportation Integrated Search

2009-04-01

A key to the successful implementation of Context Sensitive Solutions (CSS) for Illinois transportation projects is the : active and informed participation of Illinois Department of Transportations (IDOT) stakeholders. Essential to this : particip...

Correlation of immune activation with HIV-1 RNA levels assayed by real-time RT-PCR in HIV-1 Subtype C infected patients in Northern India

PubMed Central

Agarwal, Atima; Sankaran, Sumathi; Vajpayee, Madhu; Sreenivas, V; Seth, Pradeep; Dandekar, Satya

2014-01-01

Background Assays with specificity and cost effectiveness are needed for the measurement of HIV-1 burden to monitor disease progression or response to anti-retroviral therapy (ART) in HIV-1 subtype C infected patients. Objectives The objective of this study was to develop and validate an affordable; one step Real-Time RT-PCR assay with high specificity and sensitivity to measure plasma HIV-1 loads in HIV-1 subtype C infected patients. Results We developed an RT-PCR assay to detect and quantitate plasma HIV-1 levels in HIV-1 subtype C infected patients. An inverse correlation between plasma viral loads (PVL) and CD4+ T-cell numbers was detected at all CDC stages. Significant correlations were found between CD8+ T-cell activation and PVL, as well as with the clinical and immunological status of the patients. Conclusions The RT-PCR assay provides a sensitive method to measure PVL in HIV-1 subtype C infected patients. Viral loads correlated with immune activation and can be used to monitor HIV care in India. PMID:17962068

Extending Situated Language Comprehension (Accounts) with Speaker and Comprehender Characteristics: Toward Socially Situated Interpretation.

PubMed

Münster, Katja; Knoeferle, Pia

2017-01-01

More and more findings suggest a tight temporal coupling between (non-linguistic) socially interpreted context and language processing. Still, real-time language processing accounts remain largely elusive with respect to the influence of biological (e.g., age) and experiential (e.g., world and moral knowledge) comprehender characteristics and the influence of the 'socially interpreted' context, as for instance provided by the speaker. This context could include actions, facial expressions, a speaker's voice or gaze, and gestures among others. We review findings from social psychology, sociolinguistics and psycholinguistics to highlight the relevance of (the interplay between) the socially interpreted context and comprehender characteristics for language processing. The review informs the extension of an extant real-time processing account (already featuring a coordinated interplay between language comprehension and the non-linguistic visual context) with a variable ('ProCom') that captures characteristics of the language user and with a first approximation of the comprehender's speaker representation. Extending the CIA to the sCIA (social Coordinated Interplay Account) is the first step toward a real-time language comprehension account which might eventually accommodate the socially situated communicative interplay between comprehenders and speakers.

Extending Situated Language Comprehension (Accounts) with Speaker and Comprehender Characteristics: Toward Socially Situated Interpretation

PubMed Central

Münster, Katja; Knoeferle, Pia

2018-01-01

More and more findings suggest a tight temporal coupling between (non-linguistic) socially interpreted context and language processing. Still, real-time language processing accounts remain largely elusive with respect to the influence of biological (e.g., age) and experiential (e.g., world and moral knowledge) comprehender characteristics and the influence of the ‘socially interpreted’ context, as for instance provided by the speaker. This context could include actions, facial expressions, a speaker’s voice or gaze, and gestures among others. We review findings from social psychology, sociolinguistics and psycholinguistics to highlight the relevance of (the interplay between) the socially interpreted context and comprehender characteristics for language processing. The review informs the extension of an extant real-time processing account (already featuring a coordinated interplay between language comprehension and the non-linguistic visual context) with a variable (‘ProCom’) that captures characteristics of the language user and with a first approximation of the comprehender’s speaker representation. Extending the CIA to the sCIA (social Coordinated Interplay Account) is the first step toward a real-time language comprehension account which might eventually accommodate the socially situated communicative interplay between comprehenders and speakers. PMID:29416517

RoboTAP: Target priorities for robotic microlensing observations

NASA Astrophysics Data System (ADS)

Hundertmark, M.; Street, R. A.; Tsapras, Y.; Bachelet, E.; Dominik, M.; Horne, K.; Bozza, V.; Bramich, D. M.; Cassan, A.; D'Ago, G.; Figuera Jaimes, R.; Kains, N.; Ranc, C.; Schmidt, R. W.; Snodgrass, C.; Wambsganss, J.; Steele, I. A.; Mao, S.; Ment, K.; Menzies, J.; Li, Z.; Cross, S.; Maoz, D.; Shvartzvald, Y.

2018-01-01

Context. The ability to automatically select scientifically-important transient events from an alert stream of many such events, and to conduct follow-up observations in response, will become increasingly important in astronomy. With wide-angle time domain surveys pushing to fainter limiting magnitudes, the capability to follow-up on transient alerts far exceeds our follow-up telescope resources, and effective target prioritization becomes essential. The RoboNet-II microlensing program is a pathfinder project, which has developed an automated target selection process (RoboTAP) for gravitational microlensing events, which are observed in real time using the Las Cumbres Observatory telescope network. Aims: Follow-up telescopes typically have a much smaller field of view compared to surveys, therefore the most promising microlensing events must be automatically selected at any given time from an annual sample exceeding 2000 events. The main challenge is to select between events with a high planet detection sensitivity, with the aim of detecting many planets and characterizing planetary anomalies. Methods: Our target selection algorithm is a hybrid system based on estimates of the planet detection zones around a microlens. It follows automatic anomaly alerts and respects the expected survey coverage of specific events. Results: We introduce the RoboTAP algorithm, whose purpose is to select and prioritize microlensing events with high sensitivity to planetary companions. In this work, we determine the planet sensitivity of the RoboNet follow-up program and provide a working example of how a broker can be designed for a real-life transient science program conducting follow-up observations in response to alerts; we explore the issues that will confront similar programs being developed for the Large Synoptic Survey Telescope (LSST) and other time domain surveys.

A Network Architecture for Data-Driven Systems

DTIC Science & Technology

1985-07-01

ELABORATION. ..... ..... 26 Real - Time Operating System . ....... ......... 26 Secondary Memory Utilization. ........ ....... 26 Data Flow Graphical...discussions followed by a flight simulator exam~ple. REAL - TIME OPERATING SYSTEM An operating system needs to be designed exclusively for real-time...Assessment. (SDWA) module. The SDWA module is tightly coupled to the real - time operating system . This module must determine the sensitivity to

A study of design approach of spreading schemes for viral marketing based on human dynamics

NASA Astrophysics Data System (ADS)

Yang, Jianmei; Zhuang, Dong; Xie, Weicong; Chen, Guangrong

2013-12-01

Before launching a real viral marketing campaign, it is needed to design a spreading scheme by simulations. Based on a categorization of spreading patterns in real world and models, we point out that the existing research (especially Yang et al. (2010) Ref. [16]) implicitly assume that if a user decides to post a received message (is activated), he/she will take the reposting action promptly (Prompt Action After Activation, or PAAA). After a careful analysis on a real dataset however, it is found that the observed time differences between action and activation exhibit a heavy-tailed distribution. A simulation model for heavy-tailed pattern is then proposed and performed. Similarities and differences of spreading processes between the heavy-tailed and PAAA patterns are analyzed. Consequently, a more practical design approach of spreading scheme for viral marketing on QQ platform is proposed. The design approach can be extended and applied to the contexts of non-heavy-tailed pattern, and viral marketing on other instant messaging platforms.

Multiplex Real-Time PCR Assay Using TaqMan Probes for the Identification of Trypanosoma cruzi DTUs in Biological and Clinical Samples

PubMed Central

Cura, Carolina I.; Duffy, Tomas; Lucero, Raúl H.; Bisio, Margarita; Péneau, Julie; Jimenez-Coello, Matilde; Calabuig, Eva; Gimenez, María J.; Valencia Ayala, Edward; Kjos, Sonia A.; Santalla, José; Mahaney, Susan M.; Cayo, Nelly M.; Nagel, Claudia; Barcán, Laura; Málaga Machaca, Edith S.; Acosta Viana, Karla Y.; Brutus, Laurent; Ocampo, Susana B.; Aznar, Christine; Cuba Cuba, Cesar A.; Gürtler, Ricardo E.; Ramsey, Janine M.; Ribeiro, Isabela; VandeBerg, John L.; Yadon, Zaida E.; Osuna, Antonio; Schijman, Alejandro G.

2015-01-01

Background Trypanosoma cruzi has been classified into six Discrete Typing Units (DTUs), designated as TcI–TcVI. In order to effectively use this standardized nomenclature, a reproducible genotyping strategy is imperative. Several typing schemes have been developed with variable levels of complexity, selectivity and analytical sensitivity. Most of them can be only applied to cultured stocks. In this context, we aimed to develop a multiplex Real-Time PCR method to identify the six T. cruzi DTUs using TaqMan probes (MTq-PCR). Methods/Principal Findings The MTq-PCR has been evaluated in 39 cultured stocks and 307 biological samples from vectors, reservoirs and patients from different geographical regions and transmission cycles in comparison with a multi-locus conventional PCR algorithm. The MTq-PCR was inclusive for laboratory stocks and natural isolates and sensitive for direct typing of different biological samples from vectors, reservoirs and patients with acute, congenital infection or Chagas reactivation. The first round SL-IR MTq-PCR detected 1 fg DNA/reaction tube of TcI, TcII and TcIII and 1 pg DNA/reaction tube of TcIV, TcV and TcVI reference strains. The MTq-PCR was able to characterize DTUs in 83% of triatomine and 96% of reservoir samples that had been typed by conventional PCR methods. Regarding clinical samples, 100% of those derived from acute infected patients, 62.5% from congenitally infected children and 50% from patients with clinical reactivation could be genotyped. Sensitivity for direct typing of blood samples from chronic Chagas disease patients (32.8% from asymptomatic and 22.2% from symptomatic patients) and mixed infections was lower than that of the conventional PCR algorithm. Conclusions/Significance Typing is resolved after a single or a second round of Real-Time PCR, depending on the DTU. This format reduces carryover contamination and is amenable to quantification, automation and kit production. PMID:25993316

Multiplex Real-Time PCR Assay Using TaqMan Probes for the Identification of Trypanosoma cruzi DTUs in Biological and Clinical Samples.

PubMed

Cura, Carolina I; Duffy, Tomas; Lucero, Raúl H; Bisio, Margarita; Péneau, Julie; Jimenez-Coello, Matilde; Calabuig, Eva; Gimenez, María J; Valencia Ayala, Edward; Kjos, Sonia A; Santalla, José; Mahaney, Susan M; Cayo, Nelly M; Nagel, Claudia; Barcán, Laura; Málaga Machaca, Edith S; Acosta Viana, Karla Y; Brutus, Laurent; Ocampo, Susana B; Aznar, Christine; Cuba Cuba, Cesar A; Gürtler, Ricardo E; Ramsey, Janine M; Ribeiro, Isabela; VandeBerg, John L; Yadon, Zaida E; Osuna, Antonio; Schijman, Alejandro G

2015-05-01

Trypanosoma cruzi has been classified into six Discrete Typing Units (DTUs), designated as TcI-TcVI. In order to effectively use this standardized nomenclature, a reproducible genotyping strategy is imperative. Several typing schemes have been developed with variable levels of complexity, selectivity and analytical sensitivity. Most of them can be only applied to cultured stocks. In this context, we aimed to develop a multiplex Real-Time PCR method to identify the six T. cruzi DTUs using TaqMan probes (MTq-PCR). The MTq-PCR has been evaluated in 39 cultured stocks and 307 biological samples from vectors, reservoirs and patients from different geographical regions and transmission cycles in comparison with a multi-locus conventional PCR algorithm. The MTq-PCR was inclusive for laboratory stocks and natural isolates and sensitive for direct typing of different biological samples from vectors, reservoirs and patients with acute, congenital infection or Chagas reactivation. The first round SL-IR MTq-PCR detected 1 fg DNA/reaction tube of TcI, TcII and TcIII and 1 pg DNA/reaction tube of TcIV, TcV and TcVI reference strains. The MTq-PCR was able to characterize DTUs in 83% of triatomine and 96% of reservoir samples that had been typed by conventional PCR methods. Regarding clinical samples, 100% of those derived from acute infected patients, 62.5% from congenitally infected children and 50% from patients with clinical reactivation could be genotyped. Sensitivity for direct typing of blood samples from chronic Chagas disease patients (32.8% from asymptomatic and 22.2% from symptomatic patients) and mixed infections was lower than that of the conventional PCR algorithm. Typing is resolved after a single or a second round of Real-Time PCR, depending on the DTU. This format reduces carryover contamination and is amenable to quantification, automation and kit production.

Learning Activity Predictors from Sensor Data: Algorithms, Evaluation, and Applications.

PubMed

Minor, Bryan; Doppa, Janardhan Rao; Cook, Diane J

2017-12-01

Recent progress in Internet of Things (IoT) platforms has allowed us to collect large amounts of sensing data. However, there are significant challenges in converting this large-scale sensing data into decisions for real-world applications. Motivated by applications like health monitoring and intervention and home automation we consider a novel problem called Activity Prediction , where the goal is to predict future activity occurrence times from sensor data. In this paper, we make three main contributions. First, we formulate and solve the activity prediction problem in the framework of imitation learning and reduce it to a simple regression learning problem. This approach allows us to leverage powerful regression learners that can reason about the relational structure of the problem with negligible computational overhead. Second, we present several metrics to evaluate activity predictors in the context of real-world applications. Third, we evaluate our approach using real sensor data collected from 24 smart home testbeds. We also embed the learned predictor into a mobile-device-based activity prompter and evaluate the app for 9 participants living in smart homes. Our results indicate that our activity predictor performs better than the baseline methods, and offers a simple approach for predicting activities from sensor data.

A Novel Approach for Creating Activity-Aware Applications in a Hospital Environment

NASA Astrophysics Data System (ADS)

Bardram, Jakob E.

Context-aware and activity-aware computing has been proposed as a way to adapt the computer to the user’s ongoing activity. However, deductively moving from physical context - like location - to establishing human activity has proved difficult. This paper proposes a novel approach to activity-aware computing. Instead of inferring activities, this approach enables the user to explicitly model their activity, and then use sensor-based events to create, manage, and use these computational activities adjusted to a specific context. This approach was crafted through a user-centered design process in collaboration with a hospital department. We propose three strategies for activity-awareness: context-based activity matching, context-based activity creation, and context-based activity adaptation. We present the implementation of these strategies and present an experimental evaluation of them. The experiments demonstrate that rather than considering context as information, context can be a relational property that links ’real-world activities’ with their ’computational activities’.

Test Generator for MATLAB Simulations

NASA Technical Reports Server (NTRS)

Henry, Joel

2011-01-01

MATLAB Automated Test Tool, version 3.0 (MATT 3.0) is a software package that provides automated tools that reduce the time needed for extensive testing of simulation models that have been constructed in the MATLAB programming language by use of the Simulink and Real-Time Workshop programs. MATT 3.0 runs on top of the MATLAB engine application-program interface to communicate with the Simulink engine. MATT 3.0 automatically generates source code from the models, generates custom input data for testing both the models and the source code, and generates graphs and other presentations that facilitate comparison of the outputs of the models and the source code for the same input data. Context-sensitive and fully searchable help is provided in HyperText Markup Language (HTML) format.

The detection of T-Nos, a genetic element present in GMOs, by cross-priming isothermal amplification with real-time fluorescence.

PubMed

Zhang, Fang; Wang, Liu; Fan, Kai; Wu, Jian; Ying, Yibin

2014-05-01

An isothermal cross-priming amplification (CPA) assay for Agrobacterium tumefaciens nopaline synthase terminator (T-Nos) was established and investigated in this work. A set of six specific primers, recognizing eight distinct regions on the T-Nos sequence, was designed. The CPA assay was performed at a constant temperature, 63 °C, and detected by real-time fluorescence. The results indicated that real-time fluorescent CPA had high specificity, and the limit of detection was 1.06 × 10(3) copies of rice genomic DNA, which could be detected in 40 min. Comparison of real-time fluorescent CPA and conventional polymerase chain reaction (PCR) was also performed. Results revealed that real-time fluorescent CPA had a comparable sensitivity to conventional real-time PCR and had taken a shorter time. In addition, different contents of genetically modified (GM)-contaminated rice seed powder samples were detected for practical application. The result showed real-time fluorescent CPA could detect 0.5 % GM-contaminated samples at least, and the whole reaction could be finished in 35 min. Real-time fluorescent CPA is sensitive enough to monitor labeling systems and provides an attractive method for the detection of GMO.

Sensitive and real-time determination of H2O2 release from intact peroxisomes.

PubMed Central

Mueller, Sebastian; Weber, Angelika; Fritz, Reiner; Mütze, Sabine; Rost, Daniel; Walczak, Henning; Völkl, Alfred; Stremmel, Wolfgang

2002-01-01

Peroxisomes are essential and ubiquitous cell organelles having a key role in mammalian lipid and oxygen metabolism. The presence of flavine oxidases makes them an important intracellular source of H(2)O(2): an obligate product of peroxisomal redox reactions and a key reactive oxygen species. Peroxisomes proliferate in response to external signals triggered by peroxisome-proliferator-activated receptor signalling pathways. Peroxisome-derived oxidative stress as a consequence of this proliferation is increasingly recognized to participate in pathologies ranging from carcinogenesis in rodents to alcoholic and non-alcoholic steatosis hepatitis in humans. To date, no sensitive approach exists to record H(2)O(2) turnover of peroxisomes in real time. Here, we introduce a sensitive chemiluminescence method that allows the monitoring of H(2)O(2) generation and degradation in real time in suspensions of intact peroxisomes. Importantly, removal, as well as release of, H(2)O(2) can be assessed at nanomolar, non-toxic concentrations in the same sample. Owing to the kinetic properties of catalase and oxidases, H(2)O(2) forms fast steady-state concentrations in the presence of various peroxisomal substrates. Substrate screening suggests that urate, glycolate and activated fatty acids are the most important sources for H(2)O(2) in rodents. Kinetic studies imply further that peroxisomes contribute significantly to the beta-oxidation of medium-chain fatty acids, in addition to their essential role in the breakdown of long and very long ones. These observations establish a direct quantitative release of H(2)O(2) from intact peroxisomes. The experimental approach offers new possibilities for functionally studying H(2)O(2) metabolism, substrate transport and turnover in peroxisomes of eukaryotic cells. PMID:11964148

Sensitive and specific detection of classical scrapie prions in the brains of goats by real-time quaking-induced conversion.

PubMed

Dassanayake, Rohana P; Orrú, Christina D; Hughson, Andrew G; Caughey, Byron; Graça, Telmo; Zhuang, Dongyue; Madsen-Bouterse, Sally A; Knowles, Donald P; Schneider, David A

2016-03-01

Real-time quaking-induced conversion (RT-QuIC) is a rapid, specific and highly sensitive prion seeding activity detection assay that uses recombinant prion protein (rPrPSen) to detect subinfectious levels of the abnormal isoforms of the prion protein (PrPSc). Although RT-QuIC has been successfully used to detect PrPSc in various tissues from humans and animals, including sheep, tissues from goats infected with classical scrapie have not yet been tested. Therefore, the aims of the present study were to (1) evaluate whether prion seeding activity could be detected in the brain tissues of goats with scrapie using RT-QuIC, (2) optimize reaction conditions to improve scrapie detection in goats, and (3) compare the performance of RT-QuIC for the detection of PrPSc with the more commonly used ELISA and Western blot assays. We further optimized RT-QuIC conditions for sensitive and specific detection of goat scrapie seeding activity in brain tissue from clinical animals. When used with 200  mM sodium chloride, both full-length sheep rPrPSen substrates (PrP genotypes A136R154Q171 and V136R154Q171) provided good discrimination between scrapie-infected and normal goat brain samples at 10(- )3 dilution within 15  h. Our findings indicate that RT-QuIC was at least 10,000-fold more sensitive than ELISA and Western blot assays for the detection of scrapie seeding activity in goat brain samples. In addition to PRNP WT samples, positive RT-QuIC reactions were also observed with three PRNP polymorphic goat brain samples (G/S127, I/M142 and H/R143) tested. Taken together, these findings demonstrate that RT-QuIC sensitively detects prion seeding activity in classical scrapie-infected goat brain samples.

Sensitive and specific detection of classical scrapie prions in the brains of goats by real-time quaking-induced conversion

PubMed Central

Dassanayake, Rohana P.; Orrú, Christina D.; Hughson, Andrew G.; Caughey, Byron; Graça, Telmo; Zhuang, Dongyue; Madsen-Bouterse, Sally A.; Knowles, Donald P.; Schneider, David A.

2016-01-01

Real-time quaking-induced conversion (RT-QuIC) is a rapid, specific and highly sensitive prion seeding activity detection assay that uses recombinant prion protein (rPrPSen) to detect subinfectious levels of the abnormal isoforms of the prion protein (PrPSc). Although RT-QuIC has been successfully used to detect PrPSc in various tissues from humans and animals, including sheep, tissues from goats infected with classical scrapie have not yet been tested. Therefore, the aims of the present study were to (1) evaluate whether prion seeding activity could be detected in the brain tissues of goats with scrapie using RT-QuIC, (2) optimize reaction conditions to improve scrapie detection in goats, and (3) compare the performance of RT-QuIC for the detection of PrPSc with the more commonly used ELISA and Western blot assays. We further optimized RT-QuIC conditions for sensitive and specific detection of goat scrapie seeding activity in brain tissue from clinical animals. When used with 200 mM sodium chloride, both full-length sheep rPrPSen substrates (PrP genotypes A136R154Q171 and V136R154Q171) provided good discrimination between scrapie-infected and normal goat brain samples at 10− 3 dilution within 15 h. Our findings indicate that RT-QuIC was at least 10 000-fold more sensitive than ELISA and Western blot assays for the detection of scrapie seeding activity in goat brain samples. In addition to PRNP WT samples, positive RT-QuIC reactions were also observed with three PRNP polymorphic goat brain samples (G/S127, I/M142 and H/R143) tested. Taken together, these findings demonstrate that RT-QuIC sensitively detects prion seeding activity in classical scrapie-infected goat brain samples. PMID:26653410

Detection of chronic wasting disease prion seeding activity in deer and elk feces by real-time quaking-induced conversion

PubMed Central

Tennant, Joanne M.; Haley, Nicholas J.; Denkers, Nathaniel D.; Mathiason, Candace K.; Hoover, Edward A.

2017-01-01

Chronic wasting disease (CWD) is an emergent prion disease affecting cervid species in North America, Canada, South Korea, and recently, Norway. Detection of CWD has been advanced by techniques that rely on amplification of low levels of prion amyloid to a detectable level. However, the increased sensitivity of amplification assays is often compromised by inhibitors and/or activators in complex biologic samples including body fluids, excreta, or the environment. Here, we adapt real-time quaking-induced conversion conditions to specifically detect CWD prions in fecal samples from both experimentally infected deer and naturally infected elk and estimate environmental contamination. The results have application to detection, surveillance and management of CWD, and potentially to other protein-misfolding diseases. PMID:28703697

A novel multiplex real-time PCR assay for the detection and quantification of HPV16/18 and HSV1/2 in cervical cancer screening.

PubMed

Zhao, Youyun; Cao, Xuan; Tang, Jingfeng; Zhou, Li; Gao, Yinglin; Wang, Jiangping; Zheng, Yi; Yin, Shanshan; Wang, Yefu

2012-04-01

Infection with human papillomavirus (HPV), particularly HPV16 and HPV18, is the main cause of invasive cervical cancer, although other factors such as herpes simplex virus (HSV) may act in conjunction with HPV in this context. To explore the possibility of developing a system for rapid diagnosis and clinical screening of cervical cancer, we developed a multiplex real-time PCR assay that can simultaneously detect and quantify HPV16/18 and HSV1/2. To evaluate its possibilities and practical uses, 177 samples collected from patients with suspected HPV and HSV infection in exfoliated cervical cells, genital herpes or labial herpes were tested by multiplex real-time PCR and compared with results obtained by DNA sequencing. Each virus was detected over a range from 1.0 × 10(1) to 1.0 × 10(7) copies/reaction. The clinical sensitivity was 100% for HPV16/18 and HSV1/2. The clinical specificity was 97.1% for HPV16, 98.1% for HPV18, 97.0% for HSV1 and 96.0% for HSV2. The kappa value was 0.96 for HPV16, 0.92 for HPV18, 0.94 for HSV1 and 0.93 for HSV2, when DNA sequencing was used as the reference standard. In summary, this novel multiplex real-time PCR allows the rapid and specific detection of HPV16/18 and HSV1/2, as well as coinfection with HPV and HSV, in clinical samples. In the future, this multiplex real-time PCR assay will assist in cervical cancer screening, viral treatment evaluation and epidemiological studies in which high throughput analysis is required. Copyright © 2012 Elsevier Ltd. All rights reserved.

Attractor States in Teaching and Learning Processes: A Study of Out-of-School Science Education

PubMed Central

Geveke, Carla H.; Steenbeek, Henderien W.; Doornenbal, Jeannette M.; Van Geert, Paul L. C.

2017-01-01

In order for out-of-school science activities that take place during school hours but outside the school context to be successful, instructors must have sufficient pedagogical content knowledge (PCK) to guarantee high-quality teaching and learning. We argue that PCK is a quality of the instructor-pupil system that is constructed in real-time interaction. When PCK is evident in real-time interaction, we define it as Expressed Pedagogical Content Knowledge (EPCK). The aim of this study is to empirically explore whether EPCK shows a systematic pattern of variation, and if so whether the pattern occurs in recurrent and temporary stable attractor states as predicted in the complex dynamic systems theory. This study concerned nine out-of-school activities in which pupils of upper primary school classes participated. A multivariate coding scheme was used to capture EPCK in real time. A principal component analysis of the time series of all the variables reduced the number of components. A cluster revealed general descriptions of the components across all cases. Cluster analyses of individual cases divided the time series into sequences, revealing High-, Low-, and Non-EPCK states. High-EPCK attractor states emerged at particular moments during activities, rather than being present all the time. Such High-EPCK attractor states were only found in a few cases, namely those where the pupils were prepared for the visit and the instructors were trained. PMID:28316578

Relative sensitivity of conventional and real-time PCR assays for detection of SFG Rickettsia in blood and tissue samples from laboratory animals.

PubMed

Zemtsova, Galina E; Montgomery, Merrill; Levin, Michael L

2015-01-01

Studies on the natural transmission cycles of zoonotic pathogens and the reservoir competence of vertebrate hosts require methods for reliable diagnosis of infection in wild and laboratory animals. Several PCR-based applications have been developed for detection of infections caused by Spotted Fever group Rickettsia spp. in a variety of animal tissues. These assays are being widely used by researchers, but they differ in their sensitivity and reliability. We compared the sensitivity of five previously published conventional PCR assays and one SYBR green-based real-time PCR assay for the detection of rickettsial DNA in blood and tissue samples from Rickettsia- infected laboratory animals (n = 87). The real-time PCR, which detected rickettsial DNA in 37.9% of samples, was the most sensitive. The next best were the semi-nested ompA assay and rpoB conventional PCR, which detected as positive 18.4% and 14.9% samples respectively. Conventional assays targeting ompB, gltA and hrtA genes have been the least sensitive. Therefore, we recommend the SYBR green-based real-time PCR as a tool for the detection of rickettsial DNA in animal samples due to its higher sensitivity when compared to more traditional assays.

Relative Sensitivity of Conventional and Real-Time PCR Assays for Detection of SFG Rickettsia in Blood and Tissue Samples from Laboratory Animals

PubMed Central

Zemtsova, Galina E.; Montgomery, Merrill; Levin, Michael L.

2015-01-01

Studies on the natural transmission cycles of zoonotic pathogens and the reservoir competence of vertebrate hosts require methods for reliable diagnosis of infection in wild and laboratory animals. Several PCR-based applications have been developed for detection of infections caused by Spotted Fever group Rickettsia spp. in a variety of animal tissues. These assays are being widely used by researchers, but they differ in their sensitivity and reliability. We compared the sensitivity of five previously published conventional PCR assays and one SYBR green-based real-time PCR assay for the detection of rickettsial DNA in blood and tissue samples from Rickettsia- infected laboratory animals (n = 87). The real-time PCR, which detected rickettsial DNA in 37.9% of samples, was the most sensitive. The next best were the semi-nested ompA assay and rpoB conventional PCR, which detected as positive 18.4% and 14.9% samples respectively. Conventional assays targeting ompB, gltA and hrtA genes have been the least sensitive. Therefore, we recommend the SYBR green-based real-time PCR as a tool for the detection of rickettsial DNA in animal samples due to its higher sensitivity when compared to more traditional assays. PMID:25607846

Context-sensitive design and human interaction principles for usable, useful, and adoptable radars

NASA Astrophysics Data System (ADS)

McNamara, Laura A.; Klein, Laura M.

2016-05-01

The evolution of exquisitely sensitive Synthetic Aperture Radar (SAR) systems is positioning this technology for use in time-critical environments, such as search-and-rescue missions and improvised explosive device (IED) detection. SAR systems should be playing a keystone role in the United States' Intelligence, Surveillance, and Reconnaissance activities. Yet many in the SAR community see missed opportunities for incorporating SAR into existing remote sensing data collection and analysis challenges. Drawing on several years' of field research with SAR engineering and operational teams, this paper examines the human and organizational factors that mitigate against the adoption and use of SAR for tactical ISR and operational support. We suggest that SAR has a design problem, and that context-sensitive, human and organizational design frameworks are required if the community is to realize SAR's tactical potential.

A cost effective real-time PCR for the detection of adenovirus from viral swabs

PubMed Central

2013-01-01

Compared to traditional testing strategies, nucleic acid amplification tests such as real-time PCR offer many advantages for the detection of human adenoviruses. However, commercial assays are expensive and cost prohibitive for many clinical laboratories. To overcome fiscal challenges, a cost effective strategy was developed using a combination of homogenization and heat treatment with an “in-house” real-time PCR. In 196 swabs submitted for adenovirus detection, this crude extraction method showed performance characteristics equivalent to viral DNA obtained from a commercial nucleic acid extraction. In addition, the in-house real-time PCR outperformed traditional testing strategies using virus culture, with sensitivities of 100% and 69.2%, respectively. Overall, the combination of homogenization and heat treatment with a sensitive in-house real-time PCR provides accurate results at a cost comparable to viral culture. PMID:23758993

Estimation of effective brain connectivity with dual Kalman filter and EEG source localization methods.

PubMed

Rajabioun, Mehdi; Nasrabadi, Ali Motie; Shamsollahi, Mohammad Bagher

2017-09-01

Effective connectivity is one of the most important considerations in brain functional mapping via EEG. It demonstrates the effects of a particular active brain region on others. In this paper, a new method is proposed which is based on dual Kalman filter. In this method, firstly by using a brain active localization method (standardized low resolution brain electromagnetic tomography) and applying it to EEG signal, active regions are extracted, and appropriate time model (multivariate autoregressive model) is fitted to extracted brain active sources for evaluating the activity and time dependence between sources. Then, dual Kalman filter is used to estimate model parameters or effective connectivity between active regions. The advantage of this method is the estimation of different brain parts activity simultaneously with the calculation of effective connectivity between active regions. By combining dual Kalman filter with brain source localization methods, in addition to the connectivity estimation between parts, source activity is updated during the time. The proposed method performance has been evaluated firstly by applying it to simulated EEG signals with interacting connectivity simulation between active parts. Noisy simulated signals with different signal to noise ratios are used for evaluating method sensitivity to noise and comparing proposed method performance with other methods. Then the method is applied to real signals and the estimation error during a sweeping window is calculated. By comparing proposed method results in different simulation (simulated and real signals), proposed method gives acceptable results with least mean square error in noisy or real conditions.

Detection and partial discrimination of atypical and classical bovine spongiform encephalopathies in cattle and primates using real-time quaking-induced conversion assay.

PubMed

Levavasseur, Etienne; Biacabe, Anne-Gaëlle; Comoy, Emmanuel; Culeux, Audrey; Grznarova, Katarina; Privat, Nicolas; Simoneau, Steve; Flan, Benoit; Sazdovitch, Véronique; Seilhean, Danielle; Baron, Thierry; Haïk, Stéphane

2017-01-01

The transmission of classical bovine spongiform encephalopathy (C-BSE) through contaminated meat product consumption is responsible for variant Creutzfeldt-Jakob disease (vCJD) in humans. More recent and atypical forms of BSE (L-BSE and H-BSE) have been identified in cattle since the C-BSE epidemic. Their low incidence and advanced age of onset are compatible with a sporadic origin, as are most cases of Creutzfeldt-Jakob disease (CJD) in humans. Transmissions studies in primates and transgenic mice expressing a human prion protein (PrP) indicated that atypical forms of BSE may be associated with a higher zoonotic potential than classical BSE, and require particular attention for public health. Recently, methods designed to amplify misfolded forms of PrP have emerged as promising tools to detect prion strains and to study their diversity. Here, we validated real-time quaking-induced conversion assay for the discrimination of atypical and classical BSE strains using a large series of bovine samples encompassing all the atypical BSE cases detected by the French Centre of Reference during 10 years of exhaustive active surveillance. We obtained a 100% sensitivity and specificity for atypical BSE detection. In addition, the assay was able to discriminate atypical and classical BSE in non-human primates, and also sporadic CJD and vCJD in humans. The RT-QuIC assay appears as a practical means for a reliable detection of atypical BSE strains in a homologous or heterologous PrP context.

Detection of Histoplasma capsulatum from clinical specimens by cycling probe-based real-time PCR and nested real-time PCR.

PubMed

Muraosa, Yasunori; Toyotome, Takahito; Yahiro, Maki; Watanabe, Akira; Shikanai-Yasuda, Maria Aparecida; Kamei, Katsuhiko

2016-05-01

We developed new cycling probe-based real-time PCR and nested real-time PCR assays for the detection of Histoplasma capsulatum that were designed to detect the gene encoding N-acetylated α-linked acidic dipeptidase (NAALADase), which we previously identified as an H. capsulatum antigen reacting with sera from patients with histoplasmosis. Both assays specifically detected the DNAs of all H. capsulatum strains but not those of other fungi or human DNA. The limited of detection (LOD) of the real-time PCR assay was 10 DNA copies when using 10-fold serial dilutions of the standard plasmid DNA and 50 DNA copies when using human serum spiked with standard plasmid DNA. The nested real-time PCR improved the LOD to 5 DNA copies when using human serum spiked with standard plasmid DNA, which represents a 10-fold higher than that observed with the real-time PCR assay. To assess the ability of the two assays to diagnose histoplasmosis, we analyzed a small number of clinical specimens collected from five patients with histoplasmosis, such as sera (n = 4), formalin-fixed paraffin-embedded (FFPE) tissue (n = 4), and bronchoalveolar lavage fluid (BALF) (n = 1). Although clinical sensitivity of the real-time PCR assay was insufficiently sensitive (33%), the nested real-time PCR assay increased the clinical sensitivity (77%), suggesting it has a potential to be a useful method for detecting H. capsulatum DNA in clinical specimens. © 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.

[The establishment of a novel method of nano-immunomagnetic separation and Real-time PCR for detecting Vibrio cholerae from seafood].

PubMed

Cheng, Jinxia; Zeng, Jing; Liu, Li; Wei, Haiyan; Zhao, Xiaojuan; Zhang, Ximeng; Zhang, Lei; Zhang, Haiyu

2014-02-01

A novel method of Nano-Immunomagnetic Separation (Nano-IMS) plus Real-time PCR was established for detecting Vibrio cholerae. The Nano-Immunomagnetic Beads were created by using the monoclonal antibody of Vibrio cholerae, which was named Nano-IMB-Vc. Nano-IMB-Vc has specific adsorption of Vibrio cholerae, combined with Real-time PCR technology, a method for rapid detection of Vibrio cholerae was established. The capture specificity of Nano-IMB-Vc was tested by using 15 bacteria strains. The specificity of Real-time PCR method was tested by using 102 targets and 101 non-targets bacteria strains. The sensitivity of Nano-IMS plus Real-time PCR were tested in pure culture and in artificial samples and compared with NMKL No.156. The capture ratio of Nano-IMB-Vc was reached 70.2% at the level of 10(3) CFU/ml. In pure culture, the sensitivity of Nano-IMS plus Real-time PCR was reached at 5.4×10(2) CFU/ml. The specific of Real-time PCR method was tested by using 102 targets and 101 non-targets bacteria. The results showed that 102 strains of Vibrio cholerae test results were all positive, and the rest of the 101 strains of non-target bacteria test results were negative. No cross-reaction was founded. Add 1 CFU vibrio cholerae per 25 g sample, it could be detect with Nano-IMS plus Real-time PCR method after 8 hours enrichment. The Nano-IMS plus Real-time PCR method of Vibrio cholerae established in this study has good specificity and sensitivity, which could be applied to the rapid detection of Vibrio cholerae.

Miniaturized video-microscopy system for near real-time water quality biomonitoring using microfluidic chip-based devices

NASA Astrophysics Data System (ADS)

Huang, Yushi; Nigam, Abhimanyu; Campana, Olivia; Nugegoda, Dayanthi; Wlodkowic, Donald

2016-12-01

Biomonitoring studies apply biological responses of sensitive biomonitor organisms to rapidly detect adverse environmental changes such as presence of physic-chemical stressors and toxins. Behavioral responses such as changes in swimming patterns of small aquatic invertebrates are emerging as sensitive endpoints to monitor aquatic pollution. Although behavioral responses do not deliver information on an exact type or the intensity of toxicants present in water samples, they could provide orders of magnitude higher sensitivity than lethal endpoints such as mortality. Despite the advantages of behavioral biotests performed on sentinel organisms, their wider application in real-time and near realtime biomonitoring of water quality is limited by the lack of dedicated and automated video-microscopy systems. Current behavioral analysis systems rely mostly on static test conditions and manual procedures that are time-consuming and labor intensive. Tracking and precise quantification of locomotory activities of multiple small aquatic organisms requires high-resolution optical data recording. This is often problematic due to small size of fast moving animals and limitations of culture vessels that are not specially designed for video data recording. In this work, we capitalized on recent advances in miniaturized CMOS cameras, high resolution optics and biomicrofluidic technologies to develop near real-time water quality sensing using locomotory activities of small marine invertebrates. We present proof-of-concept integration of high-resolution time-resolved video recording system and high-throughput miniaturized perfusion biomicrofluidic platform for optical tracking of nauplii of marine crustacean Artemia franciscana. Preliminary data demonstrate that Artemia sp. exhibits rapid alterations of swimming patterns in response to toxicant exposure. The combination of video-microscopy and biomicrofluidic platform facilitated straightforward recording of fast moving objects. We envisage that prospectively such system can be scaled up to perform high-throughput water quality sensing in a robotic biomonitoring facility.

The role of multisensory interplay in enabling temporal expectations.

PubMed

Ball, Felix; Michels, Lara E; Thiele, Carsten; Noesselt, Toemme

2018-01-01

Temporal regularities can guide our attention to focus on a particular moment in time and to be especially vigilant just then. Previous research provided evidence for the influence of temporal expectation on perceptual processing in unisensory auditory, visual, and tactile contexts. However, in real life we are often exposed to a complex and continuous stream of multisensory events. Here we tested - in a series of experiments - whether temporal expectations can enhance perception in multisensory contexts and whether this enhancement differs from enhancements in unisensory contexts. Our discrimination paradigm contained near-threshold targets (subject-specific 75% discrimination accuracy) embedded in a sequence of distractors. The likelihood of target occurrence (early or late) was manipulated block-wise. Furthermore, we tested whether spatial and modality-specific target uncertainty (i.e. predictable vs. unpredictable target position or modality) would affect temporal expectation (TE) measured with perceptual sensitivity (d ' ) and response times (RT). In all our experiments, hidden temporal regularities improved performance for expected multisensory targets. Moreover, multisensory performance was unaffected by spatial and modality-specific uncertainty, whereas unisensory TE effects on d ' but not RT were modulated by spatial and modality-specific uncertainty. Additionally, the size of the temporal expectation effect, i.e. the increase in perceptual sensitivity and decrease of RT, scaled linearly with the likelihood of expected targets. Finally, temporal expectation effects were unaffected by varying target position within the stream. Together, our results strongly suggest that participants quickly adapt to novel temporal contexts, that they benefit from multisensory (relative to unisensory) stimulation and that multisensory benefits are maximal if the stimulus-driven uncertainty is highest. We propose that enhanced informational content (i.e. multisensory stimulation) enables the robust extraction of temporal regularities which in turn boost (uni-)sensory representations. Copyright © 2017 Elsevier B.V. All rights reserved.

A Reasoning Hardware Platform for Real-Time Common-Sense Inference

PubMed Central

Barba, Jesús; Santofimia, Maria J.; Dondo, Julio; Rincón, Fernando; Sánchez, Francisco; López, Juan Carlos

2012-01-01

Enabling Ambient Intelligence systems to understand the activities that are taking place in a supervised context is a rather complicated task. Moreover, this task cannot be successfully addressed while overlooking the mechanisms (common-sense knowledge and reasoning) that entitle us, as humans beings, to successfully undertake it. This work is based on the premise that Ambient Intelligence systems will be able to understand and react to context events if common-sense capabilities are embodied in them. However, there are some difficulties that need to be resolved before common-sense capabilities can be fully deployed to Ambient Intelligence. This work presents a hardware accelerated implementation of a common-sense knowledge-base system intended to improve response time and efficiency. PMID:23012540

Real-time monitoring of enzyme activity in a mesoporous silicon double layer

PubMed Central

Orosco, Manuel M.; Pacholski, Claudia; Sailor, Michael J.

2009-01-01

A double layer mesoporous silicon with different pore sizes functions as a nano-reactor that can isolate, filter and quantify the kinetics of enzyme reactions in real-time by optical reflectivity. This tiny reactor may be used to rapidly characterize a variety of isolated enzymes in a label-free manner. Activity of certain protease enzymes is often an indicator of disease states such as cancer1,2, stroke2, and neurodegeneracy3, and thus, there is a need for rapid assays that can characterize the kinetics and substrate specificity of enzymatic reactions. Nanostructured membranes can efficiently separate biomolecules4 but coupling a sensitive detection method remains difficult. Here we report a single mesoporous nano-reactor that can isolate and quantify in real-time the reaction products of proteases. The reactor consists of two layers of porous films electrochemically prepared from crystalline silicon. The upper layer with large pore sizes traps the protease enzymes and acts as the reactor while the lower layer with smaller pore sizes excludes the large proteins and captures the reaction products. Infiltration of the digested fragments into the lower layer produces a measurable change in optical reflectivity and this allows label-free quantification of enzyme kinetics in real-time within a volume of approximately 5 nanoliters. PMID:19350037

Real-time electrochemical LAMP: a rational comparative study of different DNA intercalating and non-intercalating redox probes.

PubMed

Martin, Alexandra; Bouffier, Laurent; Grant, Kathryn B; Limoges, Benoît; Marchal, Damien

2016-06-20

We present a comparative study of ten redox-active probes for use in real-time electrochemical loop-mediated isothermal amplification (LAMP). Our main objectives were to establish the criteria that need to be fulfilled for minimizing some of the current limitations of the technique and to provide future guidelines in the search for ideal redox reporters. To ensure a reliable comparative study, each redox probe was tested under similar conditions using the same LAMP reaction and the same entirely automatized custom-made real-time electrochemical device (designed for electrochemically monitoring in real-time and in parallel up to 48 LAMP samples). Electrochemical melt curve analyses were recorded immediately at the end of each LAMP reaction. Our results show that there are a number of intercalating and non-intercalating redox compounds suitable for real-time electrochemical LAMP and that the best candidates are those able to intercalate strongly into ds-DNA but not too much to avoid inhibition of the LAMP reaction. The strongest intercalating redox probes were finally shown to provide higher LAMP sensitivity, speed, greater signal amplitude, and cleaner-cut DNA melting curves than the non-intercalating molecules.

Simulation of a Real-Time Local Data Integration System over East-Central Florida

NASA Technical Reports Server (NTRS)

Case, Jonathan

1999-01-01

The Applied Meteorology Unit (AMU) simulated a real-time configuration of a Local Data Integration System (LDIS) using data from 15-28 February 1999. The objectives were to assess the utility of a simulated real-time LDIS, evaluate and extrapolate system performance to identify the hardware necessary to run a real-time LDIS, and determine the sensitivities of LDIS. The ultimate goal for running LDIS is to generate analysis products that enhance short-range (less than 6 h) weather forecasts issued in support of the 45th Weather Squadron, Spaceflight Meteorology Group, and Melbourne National Weather Service operational requirements. The simulation used the Advanced Regional Prediction System (ARPS) Data Analysis System (ADAS) software on an IBM RS/6000 workstation with a 67-MHz processor. This configuration ran in real-time, but not sufficiently fast for operational requirements. Thus, the AMU recommends a workstation with a 200-MHz processor and 512 megabytes of memory to run the AMU's configuration of LDIS in real-time. This report presents results from two case studies and several data sensitivity experiments. ADAS demonstrates utility through its ability to depict high-resolution cloud and wind features in a variety of weather situations. The sensitivity experiments illustrate the influence of disparate data on the resulting ADAS analyses.

Real-time full-motion color Flash lidar for target detection and identification

NASA Astrophysics Data System (ADS)

Nelson, Roy; Coppock, Eric; Craig, Rex; Craner, Jeremy; Nicks, Dennis; von Niederhausern, Kurt

2015-05-01

Greatly improved understanding of areas and objects of interest can be gained when real time, full-motion Flash LiDAR is fused with inertial navigation data and multi-spectral context imagery. On its own, full-motion Flash LiDAR provides the opportunity to exploit the z dimension for improved intelligence vs. 2-D full-motion video (FMV). The intelligence value of this data is enhanced when it is combined with inertial navigation data to produce an extended, georegistered data set suitable for a variety of analysis. Further, when fused with multispectral context imagery the typical point cloud now becomes a rich 3-D scene which is intuitively obvious to the user and allows rapid cognitive analysis with little or no training. Ball Aerospace has developed and demonstrated a real-time, full-motion LIDAR system that fuses context imagery (VIS to MWIR demonstrated) and inertial navigation data in real time, and can stream these information-rich geolocated/fused 3-D scenes from an airborne platform. In addition, since the higher-resolution context camera is boresighted and frame synchronized to the LiDAR camera and the LiDAR camera is an array sensor, techniques have been developed to rapidly interpolate the LIDAR pixel values creating a point cloud that has the same resolution as the context camera, effectively creating a high definition (HD) LiDAR image. This paper presents a design overview of the Ball TotalSight™ LIDAR system along with typical results over urban and rural areas collected from both rotary and fixed-wing aircraft. We conclude with a discussion of future work.

Efficient Authorization of Rich Presence Using Secure and Composed Web Services

NASA Astrophysics Data System (ADS)

Li, Li; Chou, Wu

This paper presents an extended Role-Based Access Control (RBAC) model for efficient authorization of rich presence using secure web services composed with an abstract presence data model. Following the information symmetry principle, the standard RBAC model is extended to support context sensitive social relations and cascaded authority. In conjunction with the extended RBAC model, we introduce an extensible presence architecture prototype using WS-Security and WS-Eventing to secure rich presence information exchanges based on PKI certificates. Applications and performance measurements of our presence system are presented to show that the proposed RBAC framework for presence and collaboration is well suited for real-time communication and collaboration.

"Egg-Streme" Egg Crashes

ERIC Educational Resources Information Center

Ward, Lauren; Lyden, Sarah; Fitzallen, Noleine

2016-01-01

Context based learning (CBL) is a powerful tool that utilises areas of student interest framed in meaningful contexts to foster development of new skills and understanding. For middle school students, engineering activities that relate to real-world problems provide suitable CBL contexts for acquiring conceptual scientific and mathematical…

Development of recombinase polymerase amplification assays for the rapid detection of peste des petits ruminants virus.

PubMed

Zhang, Yongning; Wang, Jianchang; Zhang, Zhou; Mei, Lin; Wang, Jinfeng; Wu, Shaoqiang; Lin, Xiangmei

2018-04-01

Peste des petits ruminants (PPR) is a severe infectious disease of small ruminants caused by PPR virus (PPRV). Rapid and sensitive detection of PPRV is critical for controlling PPR. This report describes the development and evaluation of a conventional reverse transcription recombinase polymerase amplification (RT-RPA) assay and a real-time RT-RPA assay, targeting the PPRV N gene. Sensitivity analysis revealed that the conventional RT-RPA assay could detect 852 copies of standard PPRV RNA per reaction at 95% probability within 20 min at 41 °C, and the real-time RT-RPA assay could detect 103 copies of RNA molecules per reaction at 95% probability. Specificity analysis showed that both assays have no cross-reactivity with nucleic acid templates prepared from other selected viruses or common pathogens. Clinical evaluation using 162 ovine and hircine serum and nasal swab samples showed that the performance of both the real-time RT-RPA assay and the conventional RT-RPA assay were comparable to that of real-time RT-PCR. The overall agreements between real-time RT-PCR and real-time RT-RPA, and conventional RT-RPA were 99.4% (161/162) and 98.8% (160/162), respectively. The R 2 value of real-time RT-RPA and real-time RT-PCR was 0.900 by linear regression analysis. Our results suggest that both RT-RPA assays have a potential application in the rapid, sensitive and specific detection of PPRV. Copyright © 2018 Elsevier B.V. All rights reserved.

Effective data validation of high-frequency data: time-point-, time-interval-, and trend-based methods.

PubMed

Horn, W; Miksch, S; Egghart, G; Popow, C; Paky, F

1997-09-01

Real-time systems for monitoring and therapy planning, which receive their data from on-line monitoring equipment and computer-based patient records, require reliable data. Data validation has to utilize and combine a set of fast methods to detect, eliminate, and repair faulty data, which may lead to life-threatening conclusions. The strength of data validation results from the combination of numerical and knowledge-based methods applied to both continuously-assessed high-frequency data and discontinuously-assessed data. Dealing with high-frequency data, examining single measurements is not sufficient. It is essential to take into account the behavior of parameters over time. We present time-point-, time-interval-, and trend-based methods for validation and repair. These are complemented by time-independent methods for determining an overall reliability of measurements. The data validation benefits from the temporal data-abstraction process, which provides automatically derived qualitative values and patterns. The temporal abstraction is oriented on a context-sensitive and expectation-guided principle. Additional knowledge derived from domain experts forms an essential part for all of these methods. The methods are applied in the field of artificial ventilation of newborn infants. Examples from the real-time monitoring and therapy-planning system VIE-VENT illustrate the usefulness and effectiveness of the methods.

Processor tradeoffs in distributed real-time systems

NASA Technical Reports Server (NTRS)

Krishna, C. M.; Shin, Kang G.; Bhandari, Inderpal S.

1987-01-01

The problem of the optimization of the design of real-time distributed systems is examined with reference to a class of computer architectures similar to the continuously reconfigurable multiprocessor flight control system structure, CM2FCS. Particular attention is given to the impact of processor replacement and the burn-in time on the probability of dynamic failure and mean cost. The solution is obtained numerically and interpreted in the context of real-time applications.

Boosting physics education through mobile augmented reality

NASA Astrophysics Data System (ADS)

Crǎciun, Dana; Bunoiu, Mǎdǎlin

2017-12-01

The integration of collaborative applications, based on modern learning technologies and the Internet, of various visualization techniques and digital strategies in open, flexible modern learning environments which facilitate access to resources, represents a challenge for physics teachers in Romania in general, and for novice teachers in particular. Although large efforts have been made worldwide to invest in educational technologies, their impact on the students' learning outcomes is quite modest. In this paper, we describe and analyze various curricular and extracurricular activities specifically designed for and undertaken by pre-service physics teachers. These activities employ new educational technologies, mobile augmented reality (MAR) and are based on modern teaching and learning theories. MAR is an extension for mobile devices of augmented reality, an interactive and in real time combination, of real and virtual objects overlaid in the real environment. The obtained results show that pre-service physics teachers are confident in using MAR in their teaching and learning activities, and consider that the activities performed helped them develop the skills necessary for science teachers in a technology-based society and to reflect upon the role of technology in the current Romanian educational context.

Appropriating Video Surveillance for Art and Environmental Awareness: Experiences from ARTiVIS.

PubMed

Mendes, Mónica; Ângelo, Pedro; Correia, Nuno; Nisi, Valentina

2018-06-01

Arts, Real-Time Video and Interactivity for Sustainability (ARTiVIS) is an ongoing collaborative research project investigating how real-time video, DIY surveillance technologies and sensor data can be used as a tool for environmental awareness, activism and artistic explorations. The project consists of a series of digital contexts for aesthetic contemplation of nature and civic engagement, aiming to foster awareness and empowerment of local populations through DIY surveillance. At the core of the ARTIVIS efforts are a series of interactive installations (namely B-Wind!, Hug@tree and Play with Fire), that make use of surveillance technologies and real-time video as raw material to promote environmental awareness through the emotion generated by real-time connections with nature. Throughout the project development, the surveillance concept has been shifting from the use of surveillance technology in a centralized platform, to the idea of veillance with distributed peer-to-peer networks that can be used for science and environmental monitoring. In this paper we present the history of the ARTiVIS project, related and inspiring work, describe ongoing research work and explore the present and future challenges of appropriating surveillance technology for artistic, educational and civic engagement purposes.

Human Behavior Analysis by Means of Multimodal Context Mining

PubMed Central

Banos, Oresti; Villalonga, Claudia; Bang, Jaehun; Hur, Taeho; Kang, Donguk; Park, Sangbeom; Huynh-The, Thien; Le-Ba, Vui; Amin, Muhammad Bilal; Razzaq, Muhammad Asif; Khan, Wahajat Ali; Hong, Choong Seon; Lee, Sungyoung

2016-01-01

There is sufficient evidence proving the impact that negative lifestyle choices have on people’s health and wellness. Changing unhealthy behaviours requires raising people’s self-awareness and also providing healthcare experts with a thorough and continuous description of the user’s conduct. Several monitoring techniques have been proposed in the past to track users’ behaviour; however, these approaches are either subjective and prone to misreporting, such as questionnaires, or only focus on a specific component of context, such as activity counters. This work presents an innovative multimodal context mining framework to inspect and infer human behaviour in a more holistic fashion. The proposed approach extends beyond the state-of-the-art, since it not only explores a sole type of context, but also combines diverse levels of context in an integral manner. Namely, low-level contexts, including activities, emotions and locations, are identified from heterogeneous sensory data through machine learning techniques. Low-level contexts are combined using ontological mechanisms to derive a more abstract representation of the user’s context, here referred to as high-level context. An initial implementation of the proposed framework supporting real-time context identification is also presented. The developed system is evaluated for various realistic scenarios making use of a novel multimodal context open dataset and data on-the-go, demonstrating prominent context-aware capabilities at both low and high levels. PMID:27517928

Human Behavior Analysis by Means of Multimodal Context Mining.

PubMed

Banos, Oresti; Villalonga, Claudia; Bang, Jaehun; Hur, Taeho; Kang, Donguk; Park, Sangbeom; Huynh-The, Thien; Le-Ba, Vui; Amin, Muhammad Bilal; Razzaq, Muhammad Asif; Khan, Wahajat Ali; Hong, Choong Seon; Lee, Sungyoung

2016-08-10

There is sufficient evidence proving the impact that negative lifestyle choices have on people's health and wellness. Changing unhealthy behaviours requires raising people's self-awareness and also providing healthcare experts with a thorough and continuous description of the user's conduct. Several monitoring techniques have been proposed in the past to track users' behaviour; however, these approaches are either subjective and prone to misreporting, such as questionnaires, or only focus on a specific component of context, such as activity counters. This work presents an innovative multimodal context mining framework to inspect and infer human behaviour in a more holistic fashion. The proposed approach extends beyond the state-of-the-art, since it not only explores a sole type of context, but also combines diverse levels of context in an integral manner. Namely, low-level contexts, including activities, emotions and locations, are identified from heterogeneous sensory data through machine learning techniques. Low-level contexts are combined using ontological mechanisms to derive a more abstract representation of the user's context, here referred to as high-level context. An initial implementation of the proposed framework supporting real-time context identification is also presented. The developed system is evaluated for various realistic scenarios making use of a novel multimodal context open dataset and data on-the-go, demonstrating prominent context-aware capabilities at both low and high levels.

Volcanology Curricula Development Aided by Online Educational Resource

NASA Astrophysics Data System (ADS)

Poland, Michael P.; van der Hoeven Kraft, Katrien J.; Teasdale, Rachel

2011-03-01

Using On-Line Volcano Monitoring Data in College and University Courses: The Volcano Exploration Project: Pu`u `Ō`ō (VEPP); Hawaii Volcanoes National Park, Hawaii, 26-30 July 2010; Volcanic activity is an excellent hook for engaging college and university students in geoscience classes. An increasing number of Internet-accessible real-time and near-real time volcano monitoring data are now available and constitute an important resource for geoscience education; however, relatively few data sets are comprehensive, and many lack background information to aid in interpretation. In response to the need for organized, accessible, and well-documented volcano education resources, the U.S. Geological Survey's Hawaiian Volcano Observatory (HVO), in collaboration with NASA and the University of Hawai`i at Manoa, established the Volcanoes Exploration Project: Pu`u `Ō`ō (VEPP). The VEPP Web site (http://vepp.wr.usgs.gov) is an educational resource that provides access, in near real time, to geodetic, seismic, and geologic data from the active Pu`u `Ō`ō eruptive vent on Kilauea volcano, Hawaii, along with background and context information. A strength of the VEPP site is the common theme of the Pu`u `Ō`ō eruption, which allows the site to be revisited multiple times to demonstrate different principles and integrate many aspects of volcanology.

Volcanology curricula development aided by online educational resource

USGS Publications Warehouse

Poland, Michael P.; Van Der Hoeven, Kraft; Teasdale, R.

2011-01-01

Using On-Line Volcano Monitoring Data in College and University Courses: The Volcano Exploration Project: Pu`u `Ō`ō (VEPP); Hawaii Volcanoes National Park, Hawaii, 26–30 July 2010; Volcanic activity is an excellent hook for engaging college and university students in geoscience classes. An increasing number of Internet-accessible real-time and near–real time volcano monitoring data are now available and constitute an important resource for geoscience education; however, relatively few data sets are comprehensive, and many lack background information to aid in interpretation. In response to the need for organized, accessible, and well-documented volcano education resources, the U.S. Geological Survey's Hawaiian Volcano Observatory (HVO), in collaboration with NASA and the University of Hawai`i at Manoa, established the Volcanoes Exploration Project: Pu`u `Ō`ō (VEPP). The VEPP Web site (http://vepp.wr.usgs.gov) is an educational resource that provides access, in near real time, to geodetic, seismic, and geologic data from the active Pu`u `Ō`ō eruptive vent on Kilauea volcano, Hawaii, along with background and context information. A strength of the VEPP site is the common theme of the Pu`u `Ō`ō eruption, which allows the site to be revisited multiple times to demonstrate different principles and integrate many aspects of volcanology.

Evaluation of a multiplex real-time PCR assay for detecting pathogens in cardiac valve tissue in patients with endocarditis.

PubMed

Fernández, Angel L; Varela, Eduardo; Martínez, Lucía; Martínez, Amparo; Sierra, Juan; González-Juanatey, José R; Regueiro, Benito

2010-10-01

With a novel real-time multiplex polymerase chain reaction test, the LightCycler SeptiFast® test, 25 bacterial and fungal species can be identified directly in blood. The SeptiFast® test has been used for rapid etiologic diagnosis in infectious endocarditis using blood samples but has not been evaluated directly on cardiac vegetations in patients being treated for infectious endocarditis. We prospectively analyzed 15 samples of heart valve tissue with active infectious endocarditis using the SeptiFast® test and compared the test's sensitivity with that of blood culture, valve tissue culture, and the SeptiFast® test in blood. The sensitivity of the SeptiFast test in heart valve tissue was 100%. The test results confirmed the diagnosis obtained using blood culture in 13 cases and identified the pathogen in 2 cases where blood culture tested negative. The sensitivity of the SeptiFast® test in heart valve tissue was greater than that obtained with conventional culture of vegetations or with the SeptiFast test in blood.

LacI(Ts)-Regulated Expression as an In Situ Intracellular Biomolecular Thermometer▿

PubMed Central

McCabe, K. M.; Lacherndo, E. J.; Albino-Flores, I.; Sheehan, E.; Hernandez, M.

2011-01-01

In response to needs for in situ thermometry, a temperature-sensitive vector was adapted to report changes in the intracellular heat content of Escherichia coli in near-real time. This model system utilized vectors expressing increasing quantities of β-galactosidase in response to stepwise temperature increases through a biologically relevant range (22 to 45°C). As judged by calibrated fluorometric and colorimetric reporters, both whole E. coli cells and lysates expressed significant repeatable changes in β-galactosidase activity that were sensitive to temperature changes of less than 1°C (35 to 45°C). This model system suggests that changes in cellular heat content can be detected independently of the medium in which cells are maintained, a feature of particular importance where the medium is heterogeneous or nonaqueous, or otherwise has a low heat transfer capacity. We report here that the intracellular temperature can be reliably obtained in near-real time using reliable fluorescent reporting systems from cellular scales, with a 20°C range of detection and at least 0.7°C sensitivity between 35 and 45°C. PMID:21378059

Ribozyme-mediated signal augmentation on a mass-sensitive biosensor.

PubMed

Knudsen, Scott M; Lee, Joonhyung; Ellington, Andrew D; Savran, Cagri A

2006-12-20

Mass-based detection methods such as the quartz crystal microbalance (QCM) offer an attractive option to label-based methods; however the sensitivity is generally lower by comparison. In particular, low-molecular-weight analytes can be difficult to detect based on mass addition alone. In this communication, we present the use of effector-dependent ribozymes (aptazymes) as reagents for augmenting small ligand detection on a mass-sensitive device. Two distinct aptazymes were chosen: an L1-ligase-based aptazyme (L1-Rev), which is activated by a small peptide (MW approximately 2.4 kDa) from the HIV-1 Rev protein, and a hammerhead cleavase-based aptazyme (HH-theo3) activated by theophylline (MW = 180 Da). Aptazyme activity was observed in real time, and low-molecular-weight analyte detection has been successfully demonstrated with both aptazymes.

Red-Emitting Fluorescent Probe for Detection of γ-Glutamyltranspeptidase and Its Application of Real-Time Imaging under Oxidative Stress in Cells and in Vivo.

PubMed

Liu, Feiyan; Wang, Zhen; Wang, Wenli; Luo, Jian-Guang; Kong, Lingyi

2018-06-19

γ-Glutamyltranspeptidase (GGT) plays critical roles in regulating various physiological/pathophysiological processes including the intracellular redox homeostasis. However, an effective fluorescent probe for dissecting the relationships between GGT and oxidative stress in vivo remains largely unexplored. Herein, we present a light-up fluorescent probe (DCDHF-Glu) with long wavelength emission (613 nm) for the highly sensitive and selective detection of GGT using dicyanomethylenedihydrofuran derivative as the fluorescent reporter and γ-glutamyl group as the enzyme-active trigger. DCDHF-Glu is competent to real-time image endogenous GGT in live cells and mice. In particular, DCDHF-Glu enables the direct real-time visualization of the upregulation of GGT under drug-induced oxidative stress in the HepG2 cells and the LO2 cells, as well as in vivo, vividly implying its excellent capacity in elucidation of GGT function in GGT-related biological events.

Development and inter-laboratory validation of unlabeled probe melting curve analysis for detection of JAK2 V617F mutation in polycythemia vera.

PubMed

Wu, Zhiyuan; Yuan, Hong; Zhang, Xinju; Liu, Weiwei; Xu, Jinhua; Zhang, Wei; Guan, Ming

2011-01-01

JAK2 V617F, a somatic point mutation that leads to constitutive JAK2 phosphorylation and kinase activation, has been incorporated into the WHO classification and diagnostic criteria of myeloid neoplasms. Although various approaches such as restriction fragment length polymorphism, amplification refractory mutation system and real-time PCR have been developed for its detection, a generic rapid closed-tube method, which can be utilized on routine genetic testing instruments with stability and cost-efficiency, has not been described. Asymmetric PCR for detection of JAK2 V617F with a 3'-blocked unlabeled probe, saturate dye and subsequent melting curve analysis was performed on a Rotor-Gene® Q real-time cycler to establish the methodology. We compared this method to the existing amplification refractory mutation systems and direct sequencing. Hereafter, the broad applicability of this unlabeled probe melting method was also validated on three diverse real-time systems (Roche LightCycler® 480, Applied Biosystems ABI® 7500 and Eppendorf Mastercycler® ep realplex) in two different laboratories. The unlabeled probe melting analysis could genotype JAK2 V617F mutation explicitly with a 3% mutation load detecting sensitivity. At level of 5% mutation load, the intra- and inter-assay CVs of probe-DNA heteroduplex (mutation/wild type) covered 3.14%/3.55% and 1.72%/1.29% respectively. The method could equally discriminate mutant from wild type samples on the other three real-time instruments. With a high detecting sensitivity, unlabeled probe melting curve analysis is more applicable to disclose JAK2 V617F mutation than conventional methodologies. Verified with the favorable inter- and intra-assay reproducibility, unlabeled probe melting analysis provided a generic mutation detecting alternative for real-time instruments.

Real-Time PCR in Clinical Microbiology: Applications for Routine Laboratory Testing

PubMed Central

Espy, M. J.; Uhl, J. R.; Sloan, L. M.; Buckwalter, S. P.; Jones, M. F.; Vetter, E. A.; Yao, J. D. C.; Wengenack, N. L.; Rosenblatt, J. E.; Cockerill, F. R.; Smith, T. F.

2006-01-01

Real-time PCR has revolutionized the way clinical microbiology laboratories diagnose many human microbial infections. This testing method combines PCR chemistry with fluorescent probe detection of amplified product in the same reaction vessel. In general, both PCR and amplified product detection are completed in an hour or less, which is considerably faster than conventional PCR detection methods. Real-time PCR assays provide sensitivity and specificity equivalent to that of conventional PCR combined with Southern blot analysis, and since amplification and detection steps are performed in the same closed vessel, the risk of releasing amplified nucleic acids into the environment is negligible. The combination of excellent sensitivity and specificity, low contamination risk, and speed has made real-time PCR technology an appealing alternative to culture- or immunoassay-based testing methods for diagnosing many infectious diseases. This review focuses on the application of real-time PCR in the clinical microbiology laboratory. PMID:16418529

Near-realtime simulations of biolelectric activity in small mammalian hearts using graphical processing units

PubMed Central

Vigmond, Edward J.; Boyle, Patrick M.; Leon, L. Joshua; Plank, Gernot

2014-01-01

Simulations of cardiac bioelectric phenomena remain a significant challenge despite continual advancements in computational machinery. Spanning large temporal and spatial ranges demands millions of nodes to accurately depict geometry, and a comparable number of timesteps to capture dynamics. This study explores a new hardware computing paradigm, the graphics processing unit (GPU), to accelerate cardiac models, and analyzes results in the context of simulating a small mammalian heart in real time. The ODEs associated with membrane ionic flow were computed on traditional CPU and compared to GPU performance, for one to four parallel processing units. The scalability of solving the PDE responsible for tissue coupling was examined on a cluster using up to 128 cores. Results indicate that the GPU implementation was between 9 and 17 times faster than the CPU implementation and scaled similarly. Solving the PDE was still 160 times slower than real time. PMID:19964295

An Adaptive Navigation Support System for Conducting Context-Aware Ubiquitous Learning in Museums

ERIC Educational Resources Information Center

Chiou, Chuang-Kai; Tseng, Judy C. R.; Hwang, Gwo-Jen; Heller, Shelly

2010-01-01

In context-aware ubiquitous learning, students are guided to learn in the real world with personalized supports from the learning system. As the learning resources are realistic objects in the real world, certain physical constraints, such as the limitation of stream of people who visit the same learning object, the time for moving from one object…

Comparative analysis of detection limits and specificity of molecular diagnostic markers for three pathogens (Microsporidia, Nosema spp.) in the key pollinators Apis mellifera and Bombus terrestris.

PubMed

Erler, Silvio; Lommatzsch, Stefanie; Lattorff, H Michael G

2012-04-01

Global pollinator decline has recently been discussed in the context of honey and bumble bee infections from various pathogens including viruses, bacteria, microsporidia and mites. The microsporidian pathogens Nosema apis, Nosema ceranae and Nosema bombi may in fact be major candidates contributing to this decline. Different molecular and non-molecular detection methods have been developed; however, a comparison, especially of the highly sensitive PCR based methods, is currently lacking. Here, we present the first comparative quantitative real-time PCR study of nine Nosema spp. primers within the framework of primer specificity and sensitivity. With the help of dilution series of defined numbers of spores, we reveal six primer pairs amplifying N. apis, six for N. bombi and four for N. ceranae. All appropriate primer pairs detected an amount of at least 10(4) spores, the majority of which were even as sensitive to detect such low amounts as 10(3) to ten spores. Species specificity of primers was observed for N. apis and N. bombi, but not for N. ceranae. Additionally, we did not find any significant correlation for the amplified fragments with PCR efficiency or the limit of detection. We discuss our findings on the background of false positive and negative results using quantitative real-time PCR. On the basis of these results, future research might be based on appropriate primer selection depending on the experimental needs. Primers may be selected on the basis of specificity or sensitivity. Pathogen species and load may be determined with higher precision enhancing all kinds of diagnostic studies.

Statistical Analysis of Time-Series from Monitoring of Active Volcanic Vents

NASA Astrophysics Data System (ADS)

Lachowycz, S.; Cosma, I.; Pyle, D. M.; Mather, T. A.; Rodgers, M.; Varley, N. R.

2016-12-01

Despite recent advances in the collection and analysis of time-series from volcano monitoring, and the resulting insights into volcanic processes, challenges remain in forecasting and interpreting activity from near real-time analysis of monitoring data. Statistical methods have potential to characterise the underlying structure and facilitate intercomparison of these time-series, and so inform interpretation of volcanic activity. We explore the utility of multiple statistical techniques that could be widely applicable to monitoring data, including Shannon entropy and detrended fluctuation analysis, by their application to various data streams from volcanic vents during periods of temporally variable activity. Each technique reveals changes through time in the structure of some of the data that were not apparent from conventional analysis. For example, we calculate the Shannon entropy (a measure of the randomness of a signal) of time-series from the recent dome-forming eruptions of Volcán de Colima (Mexico) and Soufrière Hills (Montserrat). The entropy of real-time seismic measurements and the count rate of certain volcano-seismic event types from both volcanoes is found to be temporally variable, with these data generally having higher entropy during periods of lava effusion and/or larger explosions. In some instances, the entropy shifts prior to or coincident with changes in seismic or eruptive activity, some of which were not clearly recognised by real-time monitoring. Comparison with other statistics demonstrates the sensitivity of the entropy to the data distribution, but that it is distinct from conventional statistical measures such as coefficient of variation. We conclude that each analysis technique examined could provide valuable insights for interpretation of diverse monitoring time-series.

Single tube multiplex real-time PCR for the rapid detection of herpesvirus infections of the central nervous system.

PubMed

Sankuntaw, Nipaporn; Sukprasert, Saovaluk; Engchanil, Chulapan; Kaewkes, Wanlop; Chantratita, Wasun; Pairoj, Vantanit; Lulitanond, Viraphong

2011-01-01

Human herpesvirus infection of immunocompromised hosts may lead to central nervous system (CNS) infection and diseases. In this study, a single tube multiplex real-time PCR was developed for the detection of five herpesviruses (HSV-1, HSV-2, VZV, EBV and CMV) in clinical cerebrospinal fluid (CSF) specimens. Two primer pairs specific for the herpesvirus polymerase gene and five hybridization probe pairs for the specific identification of the herpesvirus types were used in a LightCycler multiplex real-time PCR. A singleplex real-time PCR was first optimized and then applied to the multiplex real-time PCR. The singleplex and multiplex real-time PCRs showed no cross-reactivity. The sensitivity of the singleplex real-time PCR was 1 copy per reaction for each herpesvirus, while that of the multiplex real-time PCR was 1 copy per reaction for HSV-1 and VZV and 10 copies per reaction for HSV-2, EBV and CMV. Intra and inter-assay variations of the single tube multiplex assay were in the range of 0.02%-3.67% and 0.79%-4.35%, respectively. The assay was evaluated by testing 62 clinical CSF samples and was found to have equivalent sensitivity, specificity and agreement as the routine real-time PCR, but reducing time, cost and amount of used sample. Copyright © 2011 Elsevier Ltd. All rights reserved.

Lyme Borreliosis--the Utility of Improved Real-Time PCR Assay in the Detection of Borrelia burgdorferi Infections.

PubMed

Bil-Lula, Iwona; Matuszek, Patryk; Pfeiffer, Thomas; Woźniak, Mieczysław

2015-01-01

Infections of Borrelia burgdorferi sensu lato reveal clinical manifestations affecting numerous organs and tissues. The standard diagnostic procedure of these infections is quite simple if a positive history of tick exposure or typical erythema migrans appears. Lack of unequivocal clinical symptoms creates the necessity for further evaluation with laboratory tests. This study discusses the utility of a novel, improved, well-optimized, sensitive and highly specific quantitative real-time PCR assay for the diagnostics of infections caused by Borrelia burgdorferi sensu lato. We designed an improved, specific, highly sensitive real-time quantitative polymerase chain reaction (RQ-PCR) assay for the detection and quantification of all Borrelia burgdorferi genotypes. A wide validation effort was undertaken to ensure confidence in the highly sensitive and specific detection of B. burgdorferi. Due to high sensitivity and great specificity, as low as 1.6×10² copies of Borrelia per mL of whole blood could be detected. As much as 12 (3%) negative ELISA IgM results, 14 (2.8%) negative results of Line blot IgM, 11 (3.1%) and 7 (2.7%) of negative ELISA IgG and Line blot IgG results, respectively, were positive in real-time PCR. The data in this study confirms the high positive predictive value of real-time PCR test in the detection of Borrelia infections.

Carbon quantum dots-based recyclable real-time fluorescence assay for alkaline phosphatase with adenosine triphosphate as substrate.

PubMed

Qian, Zhaosheng; Chai, Lujing; Tang, Cong; Huang, Yuanyuan; Chen, Jianrong; Feng, Hui

2015-03-03

A convenient, reliable, and highly sensitive real-time assay for alkaline phosphatase (ALP) activity in the continuous and recyclable way is established on the basis of aggregation and disaggregation of carbon quantum dots (CQDs) through the competitive assay approach. CQDs and adenosine triphosphate (ATP) were used as the fluorescent indicator and substrate for ALP activity assessment, respectively. Richness of carboxyl groups on the surface of CQDs enables their severe aggregation triggered by cerium ions, which results in effective fluorescence quenching. Under the catalytic hydrolysis of ALP, ATP can be rapidly transformed to phosphate ions. Stronger affinity of phosphate ions to cerium ions than carboxyl groups is taken advantage of to achieve fluorescence recovery induced by redispersion of CQDs in the presence of ALP and ATP. Quantitative evaluation of ALP activity in a broad range from 4.6 to 383.3 U/L with the detection limit of 1.4 U/L can be realized in this way, which endows the assay with high enough sensitivity for practical detection in human serum. The assay can be used in a recyclable way for more than three times since the generated product CePO4 as a precipitate can be easily removed from the standard assay system. This strategy broadens the sensing application of fluorescent CQDs with excellent biocompatibility and provides an example based on disaggregation in optical probe development.

Quantitative real-time in vivo detection of magnetic nanoparticles by their nonlinear magnetization

NASA Astrophysics Data System (ADS)

Nikitin, M. P.; Torno, M.; Chen, H.; Rosengart, A.; Nikitin, P. I.

2008-04-01

A novel method of highly sensitive quantitative detection of magnetic nanoparticles (MP) in biological tissues and blood system has been realized and tested in real time in vivo experiments. The detection method is based on nonlinear magnetic properties of MP and the related device can record a very small relative variation of nonlinear magnetic susceptibility up to 10-8 at room temperature, providing sensitivity of several nanograms of MP in 0.1ml volume. Real-time quantitative in vivo measurements of dynamics of MP concentration in blood flow have been performed. A catheter that carried the blood flow of a rat passed through the measuring device. After an MP injection, the quantity of MP in the circulating blood was continuously recorded. The method has also been used to evaluate the MP distribution between rat's organs. Its sensitivity was compared with detection of the radioactive MP based on isotope of Fe59. The comparison of magnetic and radioactive signals in the rat's blood and organ samples demonstrated similar sensitivity for both methods. However, the proposed magnetic method is much more convenient as it is safe, less expensive, and provides real-time measurements in vivo. Moreover, the sensitivity of the method can be further improved by optimization of the device geometry.

A COTS-Based Replacement Strategy for Aging Avionics Computers

DTIC Science & Technology

2001-12-01

Communication Control Unit. A COTS-Based Replacement Strategy for Aging Avionics Computers COTS Microprocessor Real Time Operating System New Native Code...Native Code Objec ts Native Code Thread Real - Time Operating System Legacy Function x Virtual Component Environment Context Switch Thunk Add-in Replace

Effects of Real-Time Cochlear Implant Simulation on Speech Perception and Production

ERIC Educational Resources Information Center

Casserly, Elizabeth D.

2013-01-01

Real-time use of spoken language is a fundamentally interactive process involving speech perception, speech production, linguistic competence, motor control, neurocognitive abilities such as working memory, attention, and executive function, environmental noise, conversational context, and--critically--the communicative interaction between…

The Social Context of Infant Intention Understanding

ERIC Educational Resources Information Center

Dunphy-Lelii, Sarah; LaBounty, Jennifer; Lane, Jonathan D.; Wellman, Henry M.

2014-01-01

Traditional looking-time paradigms are often used to assess infants' attention to sociocognitive phenomena, but the link between these laboratory scenarios and real-world interactions is unclear. The current study investigated hypothesized relations between traditional social-cognitive looking-time paradigms and their real-world counterparts…

Novel railway-subgrade vibration monitoring technology using phase-sensitive OTDR

NASA Astrophysics Data System (ADS)

Wang, Zhaoyong; Lu, Bin; Zheng, Hanrong; Ye, Qing; Pan, Zhengqing; Cai, Haiwen; Qu, Ronghui; Fang, Zujie; Zhao, Howell

2017-04-01

High-speed railway is being developed rapidly; its safety, including infrastructure and train operation, is vital. This paper presents a railway-subgrade vibration monitoring scheme based on phase-sensitive OTDR for railway safety. The subgrade vibration is detected and rebuilt. Multi-dimension comprehensive analysis (MDCA) is proposed to identify the running train signals and illegal constructions along railway. To our best knowledge, it is the first time that a railway-subgrade vibration monitoring scheme is proposed. This scheme is proved effective by field tests for real-time train tracking and activities monitoring along railway. It provides a new passive distributed way for all-weather railway-subgrade vibration monitoring.

Clinical Validation of Multiplex Real-Time PCR Assays for Detection of Bacterial Meningitis Pathogens

PubMed Central

Theodore, M. Jordan; Mair, Raydel; Trujillo-Lopez, Elizabeth; du Plessis, Mignon; Wolter, Nicole; Baughman, Andrew L.; Hatcher, Cynthia; Vuong, Jeni; Lott, Lisa; von Gottberg, Anne; Sacchi, Claudio; McDonald, J. Matthew; Messonnier, Nancy E.; Mayer, Leonard W.

2012-01-01

Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae are important causes of meningitis and other infections, and rapid, sensitive, and specific laboratory assays are critical for effective public health interventions. Singleplex real-time PCR assays have been developed to detect N. meningitidis ctrA, H. influenzae hpd, and S. pneumoniae lytA and serogroup-specific genes in the cap locus for N. meningitidis serogroups A, B, C, W135, X, and Y. However, the assay sensitivity for serogroups B, W135, and Y is low. We aimed to improve assay sensitivity and develop multiplex assays to reduce time and cost. New singleplex real-time PCR assays for serogroup B synD, W135 synG, and Y synF showed 100% specificity for detecting N. meningitidis species, with high sensitivity (serogroup B synD, 99% [75/76]; W135 synG, 97% [38/39]; and Y synF, 100% [66/66]). The lower limits of detection (LLD) were 9, 43, and 10 copies/reaction for serogroup B synD, W135 synG, and Y synF assays, respectively, a significant improvement compared to results for the previous singleplex assays. We developed three multiplex real-time PCR assays for detection of (i) N. meningitidis ctrA, H. influenzae hpd, and S. pneumoniae lytA (NHS assay); (ii) N. meningitidis serogroups A, W135, and X (AWX assay); and (iii) N. meningitidis serogroups B, C, and Y (BCY assay). Each multiplex assay was 100% specific for detecting its target organisms or serogroups, and the LLD was similar to that for the singleplex assay. Pairwise comparison of real-time PCR between multiplex and singleplex assays showed that cycle threshold values of the multiplex assay were similar to those for the singleplex assay. There were no substantial differences in sensitivity and specificity between these multiplex and singleplex real-time PCR assays. PMID:22170919

Clinical validation of multiplex real-time PCR assays for detection of bacterial meningitis pathogens.

PubMed

Wang, Xin; Theodore, M Jordan; Mair, Raydel; Trujillo-Lopez, Elizabeth; du Plessis, Mignon; Wolter, Nicole; Baughman, Andrew L; Hatcher, Cynthia; Vuong, Jeni; Lott, Lisa; von Gottberg, Anne; Sacchi, Claudio; McDonald, J Matthew; Messonnier, Nancy E; Mayer, Leonard W

2012-03-01

Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae are important causes of meningitis and other infections, and rapid, sensitive, and specific laboratory assays are critical for effective public health interventions. Singleplex real-time PCR assays have been developed to detect N. meningitidis ctrA, H. influenzae hpd, and S. pneumoniae lytA and serogroup-specific genes in the cap locus for N. meningitidis serogroups A, B, C, W135, X, and Y. However, the assay sensitivity for serogroups B, W135, and Y is low. We aimed to improve assay sensitivity and develop multiplex assays to reduce time and cost. New singleplex real-time PCR assays for serogroup B synD, W135 synG, and Y synF showed 100% specificity for detecting N. meningitidis species, with high sensitivity (serogroup B synD, 99% [75/76]; W135 synG, 97% [38/39]; and Y synF, 100% [66/66]). The lower limits of detection (LLD) were 9, 43, and 10 copies/reaction for serogroup B synD, W135 synG, and Y synF assays, respectively, a significant improvement compared to results for the previous singleplex assays. We developed three multiplex real-time PCR assays for detection of (i) N. meningitidis ctrA, H. influenzae hpd, and S. pneumoniae lytA (NHS assay); (ii) N. meningitidis serogroups A, W135, and X (AWX assay); and (iii) N. meningitidis serogroups B, C, and Y (BCY assay). Each multiplex assay was 100% specific for detecting its target organisms or serogroups, and the LLD was similar to that for the singleplex assay. Pairwise comparison of real-time PCR between multiplex and singleplex assays showed that cycle threshold values of the multiplex assay were similar to those for the singleplex assay. There were no substantial differences in sensitivity and specificity between these multiplex and singleplex real-time PCR assays.

Real-Time and In-Flow Sensing Using a High Sensitivity Porous Silicon Microcavity-Based Sensor.

PubMed

Caroselli, Raffaele; Martín Sánchez, David; Ponce Alcántara, Salvador; Prats Quilez, Francisco; Torrijos Morán, Luis; García-Rupérez, Jaime

2017-12-05

Porous silicon seems to be an appropriate material platform for the development of high-sensitivity and low-cost optical sensors, as their porous nature increases the interaction with the target substances, and their fabrication process is very simple and inexpensive. In this paper, we present the experimental development of a porous silicon microcavity sensor and its use for real-time in-flow sensing application. A high-sensitivity configuration was designed and then fabricated, by electrochemically etching a silicon wafer. Refractive index sensing experiments were realized by flowing several dilutions with decreasing refractive indices, and measuring the spectral shift in real-time. The porous silicon microcavity sensor showed a very linear response over a wide refractive index range, with a sensitivity around 1000 nm/refractive index unit (RIU), which allowed us to directly detect refractive index variations in the 10 -7 RIU range.

Rapid and minimum invasive functional brain mapping by real-time visualization of high gamma activity during awake craniotomy.

PubMed

Ogawa, Hiroshi; Kamada, Kyousuke; Kapeller, Christoph; Hiroshima, Satoru; Prueckl, Robert; Guger, Christoph

2014-11-01

Electrocortical stimulation (ECS) is the gold standard for functional brain mapping during an awake craniotomy. The critical issue is to set aside enough time to identify eloquent cortices by ECS. High gamma activity (HGA) ranging between 80 and 120 Hz on electrocorticogram is assumed to reflect localized cortical processing. In this report, we used real-time HGA mapping and functional neuronavigation integrated with functional magnetic resonance imaging (fMRI) for rapid and reliable identification of motor and language functions. Four patients with intra-axial tumors in their dominant hemisphere underwent preoperative fMRI and lesion resection with an awake craniotomy. All patients showed significant fMRI activation evoked by motor and language tasks. During the craniotomy, we recorded electrocorticogram activity by placing subdural grids directly on the exposed brain surface. Each patient performed motor and language tasks and demonstrated real-time HGA dynamics in hand motor areas and parts of the inferior frontal gyrus. Sensitivity and specificity of HGA mapping were 100% compared with ECS mapping in the frontal lobe, which suggested HGA mapping precisely indicated eloquent cortices. We found different HGA dynamics of language tasks in frontal and temporal regions. Specificities of the motor and language-fMRI did not reach 85%. The results of HGA mapping was mostly consistent with those of ECS mapping, although fMRI tended to overestimate functional areas. This novel technique enables rapid and accurate identification of motor and frontal language areas. Furthermore, real-time HGA mapping sheds light on underlying physiological mechanisms related to human brain functions. Copyright © 2014 Elsevier Inc. All rights reserved.

Transform coding for hardware-accelerated volume rendering.

PubMed

Fout, Nathaniel; Ma, Kwan-Liu

2007-01-01

Hardware-accelerated volume rendering using the GPU is now the standard approach for real-time volume rendering, although limited graphics memory can present a problem when rendering large volume data sets. Volumetric compression in which the decompression is coupled to rendering has been shown to be an effective solution to this problem; however, most existing techniques were developed in the context of software volume rendering, and all but the simplest approaches are prohibitive in a real-time hardware-accelerated volume rendering context. In this paper we present a novel block-based transform coding scheme designed specifically with real-time volume rendering in mind, such that the decompression is fast without sacrificing compression quality. This is made possible by consolidating the inverse transform with dequantization in such a way as to allow most of the reprojection to be precomputed. Furthermore, we take advantage of the freedom afforded by off-line compression in order to optimize the encoding as much as possible while hiding this complexity from the decoder. In this context we develop a new block classification scheme which allows us to preserve perceptually important features in the compression. The result of this work is an asymmetric transform coding scheme that allows very large volumes to be compressed and then decompressed in real-time while rendering on the GPU.

A transactional framework for pediatric rehabilitation: shifting the focus to situated contexts, transactional processes, and adaptive developmental outcomes.

PubMed

King, Gillian; Imms, Christine; Stewart, Debra; Freeman, Matt; Nguyen, Tram

2018-07-01

A paradigm shift is taking place in pediatric rehabilitation research, practice, and policy - a shift towards the real-life contexts of clients rather than requiring clients to navigate the world of pediatric rehabilitation. This article proposes a conceptual framework to bring about a broader awareness of clients' lives and transactional processes of change over the life course. The framework draws attention to transactional processes by which individuals, situated in life contexts, change and adapt over the life course and, in turn, influence their contextual settings and broader environments. This framework is based on (a) basic tenets derived from foundational theories taking a life course perspective to change, and (b) transactional processes identified from relevant pediatric rehabilitation models that bring these foundational theories into the pediatric rehabilitation sphere. The framework identifies three types of transactional processes relevant to pediatric rehabilitation: facilitative, resiliency, and socialization processes. These processes describe how contexts and people mutually influence each other via opportunities and situated experiences, thus facilitating capacity, adaptation to adversity, and socialization to new roles and life transitions. The utility of the framework is considered for research, practice, service organizations, and policy. Implications for Rehabilitation The framework supports practitioners going beyond person and environment as separate entities, to provide services to the "situated person" in real-life contexts The framework shifts the focus from "body structures/functions" and "person in activity" to "person in changing and challenging life contexts" Working from a transactional perspective, practitioner-client conversations will change; practitioners will view client situations through a lens of opportunities and experiences, assess client experiences in real-life contexts, and strive to create context-based therapy opportunities The framework suggests the benefit of greater focus on resiliency processes to support client self-efficacy, self-determination, and autonomy, and socialization processes to enhance ability to enact new life roles at times of transition.

Improving visual perception through neurofeedback

PubMed Central

Scharnowski, Frank; Hutton, Chloe; Josephs, Oliver; Weiskopf, Nikolaus; Rees, Geraint

2012-01-01

Perception depends on the interplay of ongoing spontaneous activity and stimulus-evoked activity in sensory cortices. This raises the possibility that training ongoing spontaneous activity alone might be sufficient for enhancing perceptual sensitivity. To test this, we trained human participants to control ongoing spontaneous activity in circumscribed regions of retinotopic visual cortex using real-time functional MRI based neurofeedback. After training, we tested participants using a new and previously untrained visual detection task that was presented at the visual field location corresponding to the trained region of visual cortex. Perceptual sensitivity was significantly enhanced only when participants who had previously learned control over ongoing activity were now exercising control, and only for that region of visual cortex. Our new approach allows us to non-invasively and non-pharmacologically manipulate regionally specific brain activity, and thus provide ‘brain training’ to deliver particular perceptual enhancements. PMID:23223302

Comparison of Nested Polymerase Chain Reaction and Real-Time Polymerase Chain Reaction with Parasitological Methods for Detection of Strongyloides stercoralis in Human Fecal Samples

PubMed Central

Sharifdini, Meysam; Mirhendi, Hossein; Ashrafi, Keyhan; Hosseini, Mostafa; Mohebali, Mehdi; Khodadadi, Hossein; Kia, Eshrat Beigom

2015-01-01

This study was performed to evaluate nested polymerase chain reaction (PCR) and real-time PCR methods for detection of Strongyloides stercoralis in fecal samples compared with parasitological methods. A total of 466 stool samples were examined by conventional parasitological methods (formalin ether concentration [FEC] and agar plate culture [APC]). DNA was extracted using an in-house method, and mitochondrial cytochrome c oxidase subunit 1 and 18S ribosomal genes were amplified by nested PCR and real-time PCR, respectively. Among 466 samples, 12.7% and 18.2% were found infected with S. stercoralis by FEC and APC, respectively. DNA of S. stercoralis was detected in 18.9% and 25.1% of samples by real-time PCR and nested PCR, respectively. Considering parasitological methods as the diagnostic gold standard, the sensitivity and specificity of nested PCR were 100% and 91.6%, respectively, and that of real-time PCR were 84.7% and 95.8%, respectively. However, considering sequence analyzes of the selected nested PCR products, the specificity of nested PCR is increased. In general, molecular methods were superior to parasitological methods. They were more sensitive and more reliable in detection of S. stercoralis in comparison with parasitological methods. Between the two molecular methods, the sensitivity of nested PCR was higher than real-time PCR. PMID:26350449

Assessment of the U937 cell line for the detection of contact allergens

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

Python, Francois; Goebel, Carsten; Aeby, Pierre

2007-04-15

The human myeloid cell line U937 was evaluated as an in vitro test system to identify contact sensitizers in order to develop alternatives to animal tests for the cosmetic industry. Specific culture conditions (i.e., presence of interleukin-4, IL-4) were applied to obtain a dendritic cell-like phenotype. In the described test protocol, these cells were exposed to test chemicals and then analyzed by flow cytometry for CD86 expression and by quantitative real-time reverse transcriptase-polymerase chain reaction for IL-1{beta} and IL-8 gene expressions. Eight sensitizers, three non-sensitizers and five oxidative hair dye precursors were examined after 24-, 48- and 72-h exposure times.more » Test item-specific modulations of the chosen activation markers (CD86, IL-1{beta} and IL-8) suggest that this U937 activation test could discriminate test items classified as contact sensitizers or non-sensitizers in the local lymph node assay in mice (LLNA). More specifically, a test item can be considered as a potential sensitizer when it significantly induced the upregulation of the expression of at least two markers. Using this approach, we could correctly evaluate the dendritic cell (DC) activation potential for 15 out of 16 tested chemicals. We conclude that the U937 activation test may represent an useful tool in a future in vitro test battery for predicting sensitizing properties of chemicals.« less

Effect of Sequence Polymorphisms on Performance of Two Real-Time PCR Assays for Detection of Herpes Simplex Virus

PubMed Central

Stevenson, Jeffery; Hymas, Weston; Hillyard, David

2005-01-01

Herpes simplex virus (HSV) is the most common cause of acquired, sporadic encephalitis in the United States. PCR identification of HSV in spinal fluid has become the diagnostic gold standard due to its sensitivity and potential for speed, replacing other methods such as culture. We developed a real-time PCR assay to detect HSV, using a new type of hybridization probe, the Eclipse probe. In this study, we ran 323 samples (171 positives and 152 negatives) with the Eclipse real-time PCR assay and compared these results with another PCR assay using gel detection. The real-time assay agreed with our reference method for 319 out of the 323 samples tested (99%). Using two different real-time PCR platforms, we discovered that SNPs within the amplicon's probe binding region that are used to distinguish HSV-1 from HSV-2 can decrease assay sensitivity. This problem is potentially a general one for assays using fluorescent probes to detect target amplification in a real-time format. While real-time PCR can be a powerful tool in the field of infectious disease, careful sequence evaluation and clinical validation are essential in creating an effective assay. PMID:15872272

Are orchids left and dandelions right? Frontal brain activation asymmetry and its sensitivity to developmental context.

PubMed

Fortier, Paz; Van Lieshout, Ryan J; Waxman, Jordana A; Boyle, Michael H; Saigal, Saroj; Schmidt, Louis A

2014-08-01

To clarify long-standing conceptual and empirical inconsistencies in models describing the relation between frontal brain asymmetry and emotion, we tested a theory of biological sensitivity to context. We examined whether asymmetry of alpha activation in frontal brain regions, as measured by resting electroencephalography, is sensitive to early developmental contexts. Specifically, we investigated whether frontal asymmetry moderates the association between birth weight and adult outcomes. Adults with left frontal asymmetry (LFA) who were born at extremely low birth weight exhibited high levels of attention problems and withdrawn behaviors in their 30s, whereas normal-birth-weight adults with LFA had low levels of these problem behaviors. Adults with right frontal asymmetry (RFA) displayed a relatively moderate amount of problem behavior regardless of birth weight. Our findings suggest that LFA is associated with sensitivity to developmental context and may help explain why LFA is associated with both positive and negative outcomes, whereas RFA seems to be associated with a more canalized process in some contexts. © The Author(s) 2014.

Apollo Soyuz Test Project Weights and Mass Properties Operational Management System

NASA Technical Reports Server (NTRS)

Collins, M. A., Jr.; Hischke, E. R.

1975-01-01

The Apollo Soyuz Test Project (ASTP) Weights and Mass Properties Operational Management System was established to assure a timely and authoritative method of acquiring, controlling, generating, and disseminating an official set of vehicle weights and mass properties data. This paper provides an overview of the system and its interaction with the various aspects of vehicle and component design, mission planning, hardware and software simulations and verification, and real-time mission support activities. The effect of vehicle configuration, design maturity, and consumables updates is discussed in the context of weight control.

Dynamic "inline" images: context-sensitive retrieval and integration of images into Web documents.

PubMed

Kahn, Charles E

2008-09-01

Integrating relevant images into web-based information resources adds value for research and education. This work sought to evaluate the feasibility of using "Web 2.0" technologies to dynamically retrieve and integrate pertinent images into a radiology web site. An online radiology reference of 1,178 textual web documents was selected as the set of target documents. The ARRS GoldMiner image search engine, which incorporated 176,386 images from 228 peer-reviewed journals, retrieved images on demand and integrated them into the documents. At least one image was retrieved in real-time for display as an "inline" image gallery for 87% of the web documents. Each thumbnail image was linked to the full-size image at its original web site. Review of 20 randomly selected Collaborative Hypertext of Radiology documents found that 69 of 72 displayed images (96%) were relevant to the target document. Users could click on the "More" link to search the image collection more comprehensively and, from there, link to the full text of the article. A gallery of relevant radiology images can be inserted easily into web pages on any web server. Indexing by concepts and keywords allows context-aware image retrieval, and searching by document title and subject metadata yields excellent results. These techniques allow web developers to incorporate easily a context-sensitive image gallery into their documents.

Direct detection by real-time PCR of ftsI gene mutations affecting MICs of β-lactam agents for Haemophilus influenzae isolates from meningitis.

PubMed

Kishii, Kozue; Morozumi, Miyuki; Chiba, Naoko; Ono, Akiko; Ubukata, Kimiko

2011-10-01

One resistance mechanism of Haemophilus influenzae to ampicillin involves decreased affinity of penicillin-binding protein (PBP) 3 for β-lactam antibiotics reflecting amino acid substitutions in PBP3 encoded by the ftsI gene. Three amino acid substitutions, Ser385Thr, Arg517His, and Asn526Lys, are especially responsible for β-lactam resistance. We constructed a new real-time polymerase chain reaction (PCR) to directly detect these substitutions in addition to 16S ribosomal RNA (rRNA), cap, and bla(TEM) genes. Our real-time PCR was evaluated using 206 clinical H. influenzae strains isolated from pediatric patients with meningitis. Relative sensitivities and specificities of real-time PCR were 90.5-100% and 96.3-100% for all resistance classes compared with our previously reported conventional PCR. In addition, real-time PCR shortened time required from 3 h by conventional PCR to 1.5 h. When correlations between combinations of amino acid substitutions in the ftsI gene detected by real-time PCR and minimum inhibitory concentrations (MICs) of β-lactam antibiotics were evaluated, MIC(90)s of ampicillin for β-lactamase-nonproducing ampicillin-intermediate-resistant strains with Asn526Lys, β-lactamase-nonproducing, ampicillin-resistant strains with Ser385Thr, and β-lactamase-nonproducing ampicillin-resistant strains with both Asn526Lys and Ser385Thr, respectively, were two, four, and eight times higher than those for sensitive strains. Similarly, MIC(90)s of cephalosporins for these strains, respectively, were two, 16-32, and 16-32 times higher than those for sensitive strains. Thus, real-time PCR can guide antibiotic use.

EEG-based workload estimation across affective contexts

PubMed Central

Mühl, Christian; Jeunet, Camille; Lotte, Fabien

2014-01-01

Workload estimation from electroencephalographic signals (EEG) offers a highly sensitive tool to adapt the human–computer interaction to the user state. To create systems that reliably work in the complexity of the real world, a robustness against contextual changes (e.g., mood), has to be achieved. To study the resilience of state-of-the-art EEG-based workload classification against stress we devise a novel experimental protocol, in which we manipulated the affective context (stressful/non-stressful) while the participant solved a task with two workload levels. We recorded self-ratings, behavior, and physiology from 24 participants to validate the protocol. We test the capability of different, subject-specific workload classifiers using either frequency-domain, time-domain, or both feature varieties to generalize across contexts. We show that the classifiers are able to transfer between affective contexts, though performance suffers independent of the used feature domain. However, cross-context training is a simple and powerful remedy allowing the extraction of features in all studied feature varieties that are more resilient to task-unrelated variations in signal characteristics. Especially for frequency-domain features, across-context training is leading to a performance comparable to within-context training and testing. We discuss the significance of the result for neurophysiology-based workload detection in particular and for the construction of reliable passive brain–computer interfaces in general. PMID:24971046

A high speed data acquisition and analysis system for transonic velocity, density, and total temperature fluctuations

NASA Technical Reports Server (NTRS)

Clukey, Steven J.

1988-01-01

The high speed Dynamic Data Acquisition System (DDAS) is described which provides the capability for the simultaneous measurement of velocity, density, and total temperature fluctuations. The system of hardware and software is described in context of the wind tunnel environment. The DDAS replaces both a recording mechanism and a separate data processing system. The data acquisition and data reduction process has been combined within DDAS. DDAS receives input from hot wires and anemometers, amplifies and filters the signals with computer controlled modules, and converts the analog signals to digital with real-time simultaneous digitization followed by digital recording on disk or tape. Automatic acquisition (either from a computer link to an existing wind tunnel acquisition system, or from data acquisition facilities within DDAS) collects necessary calibration and environment data. The generation of hot wire sensitivities is done in DDAS, as is the application of sensitivities to the hot wire data to generate turbulence quantities. The presentation of the raw and processed data, in terms of root mean square values of velocity, density and temperature, and the processing of the spectral data is accomplished on demand in near-real-time- with DDAS. A comprehensive description of the interface to the DDAS and of the internal mechanisms will be prosented. A summary of operations relevant to the use of the DDAS will be provided.

Context-specific modulation of cocaine-induced locomotor sensitization and ERK and CREB phosphorylation in rat nucleus accumbens

PubMed Central

Marin, Marcelo T.; Berkow, Alexander; Golden, Sam A.; Koya, Eisuke; Planeta, Cleopatra S.; Hope, Bruce T.

2009-01-01

Learned associations are hypothesized to develop between drug effects and contextual stimuli during repeated drug administration to produce context-specific sensitization that is expressed only in the drug-associated environment and not in a non-drug paired environment. Neuroadaptations that mediate such context-specific behavior are largely unknown. We investigated context-specific modulation of CREB phosphorylation and four upstream kinases in nucleus accumbens that phosphorylate CREB, including ERK, PKA, CaMKII and IV. Rats received seven once daily injections of cocaine or saline in one of two distinct environments outside their home cages. Seven days later, test injections of cocaine or saline were administered in either the Paired or the Non-paired environment. CREB and ERK phosphorylation were assessed with immunohistochemistry while phosphorylation of the remaining kinases, as well as CREB and ERK, were assessed by Western blotting. Repeated cocaine administration produced context-specific sensitized locomotor responses accompanied by context-specific enhancement of the number of cocaine-induced phosphoCREB and phosphoERK immunoreactive nuclei in a minority of neurons. In contrast, CREB and CaMKIV phosphorylation in nucleus accumbens homogenates were decreased by cocaine test injections. We have recently shown that a small number of cocaine-activated accumbens neurons mediate the learned association between cocaine effects and the drug administration environment to produce context-specific sensitization. The corresponding cocaine and context-specific phosphorylation of ERK and CREB in cocaine-activated accumbens neurons in the present study suggests that this signal transduction pathway is also selectively activated in the same set of accumbens neurons. PMID:19912338

Quantitation of Marek's disease and chicken anemia viruses in organs of experimentally infected chickens and commercial chickens by multiplex real-time PCR.

PubMed

Davidson, Irit; Raibshtein, I; Al-Touri, A

2013-06-01

The worldwide distribution of chicken anemia virus (CAV) and Marek's disease virus (MDV) is well documented. In addition to their economic significance in single- or dual-virus infections, the two viruses can often accompany various other pathogens and affect poultry health either directly, by causing tumors, anemia, and delayed growth, or indirectly, by aggravating other diseases, as a result of their immunosuppressive effects. After a decade of employing the molecular diagnosis of those viruses, which replaced conventional virus isolation, we present the development of a real-time multiplex PCR for the simultaneous detection of both viruses. The real-time PCRs for MDV and for CAV alone are more sensitive than the respective end-point PCRs. In addition, the multiplex real-time shows a similar sensitivity when compared to the single real-time PCR for each virus. The newly developed real-time multiplex PCR is of importance in terms of the diagnosis and detection of low copies of each virus, MDV and CAV in single- and in multiple-virus infections, and its applicability will be further evaluated.

Rapid diagnosis of sepsis with TaqMan-Based multiplex real-time PCR.

PubMed

Liu, Chang-Feng; Shi, Xin-Ping; Chen, Yun; Jin, Ye; Zhang, Bing

2018-02-01

The survival rate of septic patients mainly depends on a rapid and reliable diagnosis. A rapid, broad range, specific and sensitive quantitative diagnostic test is the urgent need. Thus, we developed a TaqMan-Based Multiplex real-time PCR assays to identify bloodstream pathogens within a few hours. Primers and TaqMan probes were designed to be complementary to conserved regions in the 16S rDNA gene of different kinds of bacteria. To evaluate accurately, sensitively, and specifically, the known bacteria samples (Standard strains, whole blood samples) are determined by TaqMan-Based Multiplex real-time PCR. In addition, 30 blood samples taken from patients with clinical symptoms of sepsis were tested by TaqMan-Based Multiplex real-time PCR and blood culture. The mean frequency of positive for Multiplex real-time PCR was 96% at a concentration of 100 CFU/mL, and it was 100% at a concentration greater than 1000 CFU/mL. All the known blood samples and Standard strains were detected positively by TaqMan-Based Multiplex PCR, no PCR products were detected when DNAs from other bacterium were used in the multiplex assay. Among the 30 patients with clinical symptoms of sepsis, 18 patients were confirmed positive by Multiplex real-time PCR and seven patients were confirmed positive by blood culture. TaqMan-Based Multiplex real-time PCR assay with highly sensitivity, specificity and broad detection range, is a rapid and accurate method in the detection of bacterial pathogens of sepsis and should have a promising usage in the diagnosis of sepsis. © 2017 Wiley Periodicals, Inc.

Realistic Real World Contexts: Model Eliciting Activities

ERIC Educational Resources Information Center

Doruk, Bekir Kürsat

2016-01-01

Researchers have proposed a variety of methods to make a connection between real life and mathematics so that it can be learned in a practical way and enable people to utilise mathematics in their daily lives. Model-eliciting activities (MEAs) were developed to fulfil this need and are very capable of serving this purpose. The reason MEAs are so…

Gold nanoclusters-Cu(2+) ensemble-based fluorescence turn-on and real-time assay for acetylcholinesterase activity and inhibitor screening.

PubMed

Sun, Jian; Yang, Xiurong

2015-12-15

Based on the specific binding of Cu(2+) ions to the 11-mercaptoundecanoic acid (11-MUA)-protected AuNCs with intense orange-red emission, we have proposed and constructed a novel fluorescent nanomaterials-metal ions ensemble at a nonfluorescence off-state. Subsequently, an AuNCs@11-MUA-Cu(2+) ensemble-based fluorescent chemosensor, which is amenable to convenient, sensitive, selective, turn-on and real-time assay of acetylcholinesterase (AChE), could be developed by using acetylthiocholine (ATCh) as the substrate. Herein, the sensing ensemble solution exhibits a marvelous fluorescent enhancement in the presence of AChE and ATCh, where AChE hydrolyzes its active substrate ATCh into thiocholine (TCh), and then TCh captures Cu(2+) from the ensemble, accompanied by the conversion from fluorescence off-state to on-state of the AuNCs. The AChE activity could be detected less than 0.05 mU/mL within a good linear range from 0.05 to 2.5 mU/mL. Our proposed fluorescence assay can be utilized to evaluate the AChE activity quantitatively in real biological sample, and furthermore to screen the inhibitor of AChE. As far as we know, the present study has reported the first analytical proposal for sensing AChE activity in real time by using a fluorescent nanomaterials-Cu(2+) ensemble or focusing on the Cu(2+)-triggered fluorescence quenching/recovery. This strategy paves a new avenue for exploring the biosensing applications of fluorescent AuNCs, and presents the prospect of AuNCs@11-MUA-Cu(2+) ensemble as versatile enzyme activity assay platforms by means of other appropriate substrates/analytes. Copyright © 2015 Elsevier B.V. All rights reserved.

Molecular sensitivity threshold of wet mount and an immunochromatographic assay evaluated by quantitative real-time PCR for diagnosis of Trichomonas vaginalis infection in a low-risk population of childbearing women.

PubMed

Leli, Christian; Castronari, Roberto; Levorato, Lucia; Luciano, Eugenio; Pistoni, Eleonora; Perito, Stefano; Bozza, Silvia; Mencacci, Antonella

2016-06-01

Vaginal trichomoniasis is a sexually transmitted infection caused by Trichomonas vaginalis, a flagellated protozoan. Diagnosis of T. vaginalis infection is mainly performed by wet mount microscopy, with a sensitivity ranging from 38% to 82%, compared to culture, still considered the gold standard. Commercial immunochromatographic tests for monoclonal-antibody-based detection have been introduced as alternative methods for diagnosis of T. vaginalis infection and have been reported in some studies to be more sensitive than wet mount. Real-time PCR methods have been recently developed, with optimal sensitivity and specificity. The aim of this study was to evaluate whether there is a molecular sensitivity threshold for both wet mount and imunochromatographic assays. To this aim, a total of 1487 low-risk childbearing women (median age 32 years, interquartile range 27-37) were included in the study, and underwent vaginal swab for T. vaginalis detection by means of a quantitative real-time PCR assay, wet mount and an immunochromatographic test. Upon comparing the results, prevalence values observed were 1.3% for real-time PCR, 0.5% for microscopic examination, and 0.8% for the immunochromatographic test. Compared to real-time PCR, wet mount sensitivity was 40% (95% confidence interval 19.1% to 63.9%) and specificity was 100% (95% CI 99.7% to 100%). The sensitivity and specificity of the immunochromatographic assay were 57.9% (95% CI 33.5% to 79.8%) and 99.9% (95% CI 99.6% to 100%), respectively. Evaluation of the wet mount results and those of immunochromatographic assay detection in relation to the number of T. vaginalis DNA copies detected in vaginal samples showed that the lower identification threshold for both wet mount (chi-square 6.1; P = 0.016) and the immunochromatographic assay (chi-square 10.7; P = 0.002) was ≥100 copies of T. vaginalis DNA/5 mcl of eluted DNA.

Fully Automated Quantification of Cytomegalovirus (CMV) in Whole Blood with the New Sensitive Abbott RealTime CMV Assay in the Era of the CMV International Standard

PubMed Central

Schnepf, Nathalie; Scieux, Catherine; Resche-Riggon, Matthieu; Feghoul, Linda; Xhaard, Alienor; Gallien, Sébastien; Molina, Jean-Michel; Socié, Gérard; Viglietti, Denis; Simon, François; Mazeron, Marie-Christine

2013-01-01

Fully standardized reproducible and sensitive quantification assays for cytomegalovirus (CMV) are needed to better define thresholds for antiviral therapy initiation and interruption. We evaluated the newly released Abbott RealTime CMV assay for CMV quantification in whole blood (WB) that includes automated extraction and amplification (m2000 RealTime system). Sensitivity, accuracy, linearity, and intra- and interassay variability were validated in a WB matrix using Quality Control for Molecular Diagnostics (QCMD) panels and the WHO international standard (IS). The intra- and interassay coefficients of variation were 1.37% and 2.09% at 5 log10 copies/ml and 2.41% and 3.80% at 3 log10 copies/ml, respectively. According to expected values for the QCMD and Abbott RealTime CMV methods, the lower limits of quantification were 104 and <50 copies/ml, respectively. The conversion factor between international units and copies (2.18), determined from serial dilutions of the WHO IS in WB, was significantly different from the factor provided by the manufacturer (1.56) (P = 0.001). Results from 302 clinical samples were compared with those from the Qiagen artus CMV assay on the same m2000 RealTime system. The two assays provided highly concordant results (concordance correlation coefficient, 0.92), but the Abbott RealTime CMV assay detected and quantified, respectively, 20.6% and 47.8% more samples than the Qiagen/artus CMV assay. The sensitivity and reproducibility of the results, along with the automation, fulfilled the quality requirements for implementation of the Abbott RealTime CMV assay in clinical settings. Our results highlight the need for careful validation of conversion factors provided by the manufacturers for the WHO IS in WB to allow future comparison of results obtained with different assays. PMID:23616450

Newly emerging mutations in the matrix genes of the human influenza A(H1N1)pdm09 and A(H3N2) viruses reduce the detection sensitivity of real-time reverse transcription-PCR.

PubMed

Yang, Ji-Rong; Kuo, Chuan-Yi; Huang, Hsiang-Yi; Wu, Fu-Ting; Huang, Yi-Lung; Cheng, Chieh-Yu; Su, Yu-Ting; Chang, Feng-Yee; Wu, Ho-Sheng; Liu, Ming-Tsan

2014-01-01

New variants of the influenza A(H1N1)pdm09 and A(H3N2) viruses were detected in Taiwan between 2012 and 2013. Some of these variants were not detected in clinical specimens using a common real-time reverse transcription-PCR (RT-PCR) assay that targeted the conserved regions of the viral matrix (M) genes. An analysis of the M gene sequences of the new variants revealed that several newly emerging mutations were located in the regions where the primers or probes of the real-time RT-PCR assay bind; these included three mutations (G225A, T228C, and G238A) in the A(H1N1)pdm09 virus, as well as one mutation (C163T) in the A(H3N2) virus. These accumulated mismatch mutations, together with the previously identified C154T mutation of the A(H1N1)pdm09 virus and the C153T and G189T mutations of the A(H3N2) virus, result in a reduced detection sensitivity for the real-time RT-PCR assay. To overcome the loss of assay sensitivity due to mismatch mutations, we established a real-time RT-PCR assay using degenerate nucleotide bases in both the primers and probe and successfully increased the sensitivity of the assay to detect circulating variants of the human influenza A viruses. Our observations highlight the importance of the simultaneous use of different gene-targeting real-time RT-PCR assays for the clinical diagnosis of influenza.

Real-time fluorescence ligase chain reaction for sensitive detection of single nucleotide polymorphism based on fluorescence resonance energy transfer.

PubMed

Sun, Yueying; Lu, Xiaohui; Su, Fengxia; Wang, Limei; Liu, Chenghui; Duan, Xinrui; Li, Zhengping

2015-12-15

Most of practical methods for detection of single nucleotide polymorphism (SNP) need at least two steps: amplification (usually by PCR) and detection of SNP by using the amplification products. Ligase chain reaction (LCR) can integrate the amplification and allele discrimination in one step. However, the detection of LCR products still remains a great challenge for highly sensitive and quantitative SNP detection. Herein, a simple but robust strategy for real-time fluorescence LCR has been developed for highly sensitive and quantitative SNP detection. A pair of LCR probes are firstly labeled with a fluorophore and a quencher, respectively. When the pair of LCR probes are ligated in LCR, the fluorophore will be brought close to the quencher, and thus, the fluorescence will be specifically quenched by fluorescence resonance energy transfer (FRET). The decrease of fluorescence intensity resulted from FRET can be real-time monitored in the LCR process. With the proposed real-time fluorescence LCR assay, 10 aM DNA targets or 100 pg genomic DNA can be accurately determined and as low as 0.1% mutant DNA can be detected in the presence of a large excess of wild-type DNA, indicating the high sensitivity and specificity. The real-time measuring does not require the detection step after LCR and gives a wide dynamic range for detection of DNA targets (from 10 aM to 1 pM). As LCR has been widely used for detection of SNP, DNA methylation, mRNA and microRNA, the real-time fluorescence LCR assay shows great potential for various genetic analysis. Copyright © 2015 Elsevier B.V. All rights reserved.

Sensitivity analysis of water consumption in an office building

NASA Astrophysics Data System (ADS)

Suchacek, Tomas; Tuhovcak, Ladislav; Rucka, Jan

2018-02-01

This article deals with sensitivity analysis of real water consumption in an office building. During a long-term real study, reducing of pressure in its water connection was simulated. A sensitivity analysis of uneven water demand was conducted during working time at various provided pressures and at various time step duration. Correlations between maximal coefficients of water demand variation during working time and provided pressure were suggested. The influence of provided pressure in the water connection on mean coefficients of water demand variation was pointed out, altogether for working hours of all days and separately for days with identical working hours.

Novel Acoustic Techniques for Assessing Fish Schooling in the Context of an Operational Ocean Observatory

DTIC Science & Technology

2007-09-30

which provides real-time data throughout the Mid-Atlantic Bight (MAB). The surveys will be positioned adaptively using real-time data collected with the...dense, monotypic aggregations of a pelagic gastropod were located during a 2-day period. These aggregations were remarkablystrong scatterers at

An Expert System-based Context-Aware Ubiquitous Learning Approach for Conducting Science Learning Activities

ERIC Educational Resources Information Center

Wu, Po-Han; Hwang, Gwo-Jen; Tsai, Wen-Hung

2013-01-01

Context-aware ubiquitous learning has been recognized as being a promising approach that enables students to interact with real-world learning targets with supports from the digital world. Several researchers have indicated the importance of providing learning guidance or hints to individual students during the context-aware ubiquitous learning…

SensiScreen® KRAS exon 2-sensitive simplex and multiplex real-time PCR-based assays for detection of KRAS exon 2 mutations

PubMed Central

Guldmann-Christensen, Mariann; Hauge Kyneb, Majbritt; Voogd, Kirsten; Andersen, Christina; Epistolio, Samantha; Merlo, Elisabetta; Yding Wolff, Tine; Hamilton-Dutoit, Stephen; Lorenzen, Jan; Christensen, Ulf Bech

2017-01-01

Activating mutations in codon 12 and codon 13 of the KRAS (Kirsten rat sarcoma viral oncogene homolog) gene are implicated in the development of several human cancer types and influence their clinical evaluation, treatment and prognosis. Numerous different methods for KRAS genotyping are currently available displaying a wide range of sensitivities, time to answer and requirements for laboratory equipment and user skills. Here we present SensiScreen® KRAS exon 2 simplex and multiplex CE IVD assays, that use a novel real-time PCR-based method for KRAS mutation detection based on PentaBase’s proprietary DNA analogue technology and designed to work on standard real-time PCR instruments. By means of the included BaseBlocker™ technology, we show that SensiScreen® specifically amplifies the mutated alleles of interest with no or highly subdued amplification of the wild type allele. Furthermore, serial dilutions of mutant DNA in a wild type background demonstrate that all SensiScreen® assays display a limit of detection that falls within the range of 0.25–1%. Finally, in three different colorectal cancer patient populations, SensiScreen® assays confirmed the KRAS genotype previously determined by commonly used methods for KRAS mutation testing, and notably, in two of the populations, SensiScreen® identified additional mutant positive cases not detected by common methods. PMID:28636636

[Development of fluorescent probes for bone imaging in vivo ~Fluorescent probes for intravital imaging of osteoclast activity~.

PubMed

Minoshima, Masafumi; Kikuchi, Kazuya

Fluorescent molecules are widely used as a tool to directly visualize target biomolecules in vivo. Fluorescent probes have the advantage that desired function can be rendered based on rational design. For bone-imaging fluorescent probes in vivo, they should be delivered to bone tissue upon administration. Recently, a fluorescent probe for detecting osteoclast activity was developed. The fluorescent probe has acid-sensitive fluorescence property, specific delivery to bone tissue, and durability against laser irradiation, which enabled real-time intravital imaging of bone-resorbing osteoclasts for a long period of time.

Rapid detection of health-care-associated bloodstream infection in critical care using multipathogen real-time polymerase chain reaction technology: a diagnostic accuracy study and systematic review.

PubMed

Warhurst, Geoffrey; Dunn, Graham; Chadwick, Paul; Blackwood, Bronagh; McAuley, Daniel; Perkins, Gavin D; McMullan, Ronan; Gates, Simon; Bentley, Andrew; Young, Duncan; Carlson, Gordon L; Dark, Paul

2015-05-01

There is growing interest in the potential utility of real-time polymerase chain reaction (PCR) in diagnosing bloodstream infection by detecting pathogen deoxyribonucleic acid (DNA) in blood samples within a few hours. SeptiFast (Roche Diagnostics GmBH, Mannheim, Germany) is a multipathogen probe-based system targeting ribosomal DNA sequences of bacteria and fungi. It detects and identifies the commonest pathogens causing bloodstream infection. As background to this study, we report a systematic review of Phase III diagnostic accuracy studies of SeptiFast, which reveals uncertainty about its likely clinical utility based on widespread evidence of deficiencies in study design and reporting with a high risk of bias. Determine the accuracy of SeptiFast real-time PCR for the detection of health-care-associated bloodstream infection, against standard microbiological culture. Prospective multicentre Phase III clinical diagnostic accuracy study using the standards for the reporting of diagnostic accuracy studies criteria. Critical care departments within NHS hospitals in the north-west of England. Adult patients requiring blood culture (BC) when developing new signs of systemic inflammation. SeptiFast real-time PCR results at species/genus level compared with microbiological culture in association with independent adjudication of infection. Metrics of diagnostic accuracy were derived including sensitivity, specificity, likelihood ratios and predictive values, with their 95% confidence intervals (CIs). Latent class analysis was used to explore the diagnostic performance of culture as a reference standard. Of 1006 new patient episodes of systemic inflammation in 853 patients, 922 (92%) met the inclusion criteria and provided sufficient information for analysis. Index test assay failure occurred on 69 (7%) occasions. Adult patients had been exposed to a median of 8 days (interquartile range 4-16 days) of hospital care, had high levels of organ support activities and recent antibiotic exposure. SeptiFast real-time PCR, when compared with culture-proven bloodstream infection at species/genus level, had better specificity (85.8%, 95% CI 83.3% to 88.1%) than sensitivity (50%, 95% CI 39.1% to 60.8%). When compared with pooled diagnostic metrics derived from our systematic review, our clinical study revealed lower test accuracy of SeptiFast real-time PCR, mainly as a result of low diagnostic sensitivity. There was a low prevalence of BC-proven pathogens in these patients (9.2%, 95% CI 7.4% to 11.2%) such that the post-test probabilities of both a positive (26.3%, 95% CI 19.8% to 33.7%) and a negative SeptiFast test (5.6%, 95% CI 4.1% to 7.4%) indicate the potential limitations of this technology in the diagnosis of bloodstream infection. However, latent class analysis indicates that BC has a low sensitivity, questioning its relevance as a reference test in this setting. Using this analysis approach, the sensitivity of the SeptiFast test was low but also appeared significantly better than BC. Blood samples identified as positive by either culture or SeptiFast real-time PCR were associated with a high probability (> 95%) of infection, indicating higher diagnostic rule-in utility than was apparent using conventional analyses of diagnostic accuracy. SeptiFast real-time PCR on blood samples may have rapid rule-in utility for the diagnosis of health-care-associated bloodstream infection but the lack of sensitivity is a significant limiting factor. Innovations aimed at improved diagnostic sensitivity of real-time PCR in this setting are urgently required. Future work recommendations include technology developments to improve the efficiency of pathogen DNA extraction and the capacity to detect a much broader range of pathogens and drug resistance genes and the application of new statistical approaches able to more reliably assess test performance in situation where the reference standard (e.g. blood culture in the setting of high antimicrobial use) is prone to error. The systematic review is registered as PROSPERO CRD42011001289. The National Institute for Health Research Health Technology Assessment programme. Professor Daniel McAuley and Professor Gavin D Perkins contributed to the systematic review through their funded roles as codirectors of the Intensive Care Foundation (UK).

Comparison of HORACE and PHOTOS Algorithms for Multi-Photon Emission in the Context of the W Boson Mass Measurement

DOE PAGES

Kotwal, Ashutosh V.; Jayatilaka, Bodhitha

2016-01-01

W boson mass measurement is sensitive to QED radiative corrections due to virtual photon loops and real photon emission. The largest shift in the measured mass, which depends on the transverse momentum spectrum of the charged lepton from the boson decay, is caused by the emission of real photons from the final-state lepton. There are a number of calculations and codes available to model the final-state photon emission. We perform a detailed study, comparing the results from HORACE and PHOTOS implementations of the final-state multiphoton emission in the context of a direct measurement ofW boson mass at Tevatron. Mass fitsmore » are performed using a simulation of the CDF II detector.« less

Augmented reality enabling intelligence exploitation at the edge

NASA Astrophysics Data System (ADS)

Kase, Sue E.; Roy, Heather; Bowman, Elizabeth K.; Patton, Debra

2015-05-01

Today's Warfighters need to make quick decisions while interacting in densely populated environments comprised of friendly, hostile, and neutral host nation locals. However, there is a gap in the real-time processing of big data streams for edge intelligence. We introduce a big data processing pipeline called ARTEA that ingests, monitors, and performs a variety of analytics including noise reduction, pattern identification, and trend and event detection in the context of an area of operations (AOR). Results of the analytics are presented to the Soldier via an augmented reality (AR) device Google Glass (Glass). Non-intrusive AR devices such as Glass can visually communicate contextually relevant alerts to the Soldier based on the current mission objectives, time, location, and observed or sensed activities. This real-time processing and AR presentation approach to knowledge discovery flattens the intelligence hierarchy enabling the edge Soldier to act as a vital and active participant in the analysis process. We report preliminary observations testing ARTEA and Glass in a document exploitation and person of interest scenario simulating edge Soldier participation in the intelligence process in disconnected deployment conditions.

Detection of mRNA by reverse transcription PCR as an indicator of viability in Phytophthora ramorum

Treesearch

Antonio Chimento; Santa Olga Cacciola; Matteo Garbelotto

2008-01-01

Real-Time PCR technologies offer increasing opportunities to detect and study phytopathogenic fungi. They combine the sensitivity of conventional PCR with the generation of a specific fluorescent signal providing both real-time analysis of the reaction kinetics and quantification of specific DNA targets. Before the development of Real-Time PCR and...

Nanoparticle detection using dual-phase interferometry

PubMed Central

Deutsch, Bradley; Beams, Ryan; Novotny, Lukas

2013-01-01

Detection and identification of nanoparticles is of growing interest in atmospheric monitoring, medicine and semiconductor manufacturing. While elastic light scattering with interferometric detection provides good sensitivity to single particles, active optical components prevent scalability realistic sizes for deployment in the field or clinic. Here we report on a simple phase-sensitive nanoparticle detection scheme with no active optical elements. Two measurements are taken simultaneously, allowing amplitude and phase to be decoupled. We demonstrate detection of 25 nm Au particles in liquid in Δt ~ 1 ms with a signal-to-noise ratio of 37. Such performance makes it possible to detect nanoscale contaminants or larger proteins in real time without the need of artificial labeling. PMID:20830181

New generation QuIC assays for prion seeding activity.

PubMed

Orrù, Christina D; Wilham, Jason M; Vascellari, Sarah; Hughson, Andrew G; Caughey, Byron

2012-01-01

The ability of abnormal TSE-associated forms of PrP to seed the formation of amyloid fibrils from recombinant PrP(Sen) has served as the basis for several relatively rapid and highly sensitive tests for prion diseases. These tests include rPrP-PMCA (rPMCA), standard quaking-induced conversion (S-QuIC), amyloid seeding assay (ASA), real-time QuIC (RT-QuIC) and enhanced QuIC (eQuIC). Here, we summarize recent improvements in the RT-QuIC-based assays that enhance the practicality, sensitivity and quantitative attributes of assays QuIC and promote the detection of prion seeding activity in dilute, inhibitor-laden fluids such as blood plasma.

Rapid, cost-effective, sensitive and quantitative detection of Acinetobacter baumannii from pneumonia patients

PubMed Central

Nomanpour, B; Ghodousi, A; Babaei, A; Abtahi, HR; Tabrizi, M; Feizabadi, MM

2011-01-01

Background and Objectives Pneumonia with Acinetobacter baumannii has a major therapeutic problem in health care settings. Decision to initiate correct antibiotic therapy requires rapid identification and quantification of organism. The aim of this study was to develop a rapid and sensitive method for direct detection of A. baumannii from respiratory specimens. Materials and Methods A Taqman real time PCR based on the sequence of bla oxa-51 was designed and used for direct detection of A. baumannii from 361 respiratory specimens of patients with pneumonia. All specimens were checked by conventional bacteriology in parallel. Results The new real time PCR could detect less than 200 cfu per ml of bacteria in specimens. There was agreement between the results of real time PCR and culture (Kappa value 1.0, p value<0.001). The sensitivity, specificity and predictive values of real time PCR were 100%. The prevalence of A. baumannii in pneumonia patients was 10.53 % (n=38). Poly-microbial infections were detected in 65.71% of specimens. Conclusion Acinetobacter baumannii is the third causative agent in nosocomial pneumonia after Pseudomonas aeroginosa (16%) and Staphylococcus aureus (13%) at Tehran hospitals. We recommend that 104 CFU be the threshold for definition of infection with A. baumannii using real time PCR. PMID:22530083

Real-time electrochemical detection of hydrogen peroxide secretion in live cells by Pt nanoparticles decorated graphene-carbon nanotube hybrid paper electrode.

PubMed

Sun, Yimin; He, Kui; Zhang, Zefen; Zhou, Aijun; Duan, Hongwei

2015-06-15

In this work, we develop a new type of flexible and lightweight electrode based on highly dense Pt nanoparticles decorated free-standing graphene-carbon nanotube (CNT) hybrid paper (Pt/graphene-CNT paper), and explore its practical application as flexible electrochemical biosensor for the real-time tracking hydrogen peroxide (H2O2) secretion by live cells. For the fabrication of flexible nanohybrid electrode, the incorporation of CNT in graphene paper not only improves the electrical conductivity and the mechanical strength of graphene paper, but also increases its surface roughness and provides more nucleation sites for metal nanoparticles. Ultrafine Pt nanoparticles are further decorated on graphene-CNT paper by well controlled sputter deposition method, which offers several advantages such as defined particle size and dispersion, high loading density and strong adhesion between the nanoparticles and the substrate. Consequently, the resultant flexible Pt/graphene-CNT paper electrode demonstrates a variety of desirable electrochemical properties including large electrochemical active surface area, excellent electrocatalytic activity, high stability and exceptional flexibility. When used for nonenzymatic detection of H2O2, Pt/graphene-CNT paper exhibits outstanding sensing performance such as high sensitivity, selectivity, stability and reproducibility. The sensitivity is 1.41 µA µM(-1) cm(-2) with a linear range up to 25 µM and a low detection limit of 10 nM (S/N=3), which enables the resultant biosensor for the real-time tracking H2O2 secretion by live cells macrophages. Copyright © 2015. Published by Elsevier B.V.

7 CFR 3565.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... and use of real property for a specified period of time. Lease. A contract containing the rights and... construction contingency reserve will be held in the operating and maintenance reserve and cannot be released.... The process of evaluating real estate in the context of a real estate transaction for the presence of...

Injection moulded microneedle sensor for real-time wireless pH monitoring.

PubMed

Mirza, Khalid B; Zuliani, Claudio; Hou, Benjamin; Ng, Fu Siong; Peters, Nicholas S; Toumazou, Christofer

2017-07-01

This paper describes the development of an array of individually addressable pH sensitive microneedles using injection moulding and their integration within a portable device for real-time wireless recording of pH distributions in biological samples. The fabricated microneedles are subjected to gold patterning followed by electrodeposition of iridium oxide to sensitize them to 0.07 units of pH change. Miniaturised electronics suitable for the sensors readout, analog-to-digital conversion and wireless transmission of the potentiometric data are embodied within the device, enabling it to measure real-time pH of soft biological samples such as muscles. In this paper, real-time recording of the cardiac pH distribution, during ischemia followed by reperfusion cycles in cardiac muscles of male Wistar rats has been demonstrated by using the microneedle array.

Polymerase/DNA interactions and enzymatic activity: multi-parameter analysis with electro-switchable biosurfaces

NASA Astrophysics Data System (ADS)

Langer, Andreas; Schräml, Michael; Strasser, Ralf; Daub, Herwin; Myers, Thomas; Heindl, Dieter; Rant, Ulrich

2015-07-01

The engineering of high-performance enzymes for future sequencing and PCR technologies as well as the development of many anticancer drugs requires a detailed analysis of DNA/RNA synthesis processes. However, due to the complex molecular interplay involved, real-time methodologies have not been available to obtain comprehensive information on both binding parameters and enzymatic activities. Here we introduce a chip-based method to investigate polymerases and their interactions with nucleic acids, which employs an electrical actuation of DNA templates on microelectrodes. Two measurement modes track both the dynamics of the induced switching process and the DNA extension simultaneously to quantitate binding kinetics, dissociation constants and thermodynamic energies. The high sensitivity of the method reveals previously unidentified tight binding states for Taq and Pol I (KF) DNA polymerases. Furthermore, the incorporation of label-free nucleotides can be followed in real-time and changes in the DNA polymerase conformation (finger closing) during enzymatic activity are observable.

Enactive cinema paves way for understanding complex real-time social interaction in neuroimaging experiments

PubMed Central

Tikka, Pia; Väljamäe, Aleksander; de Borst, Aline W.; Pugliese, Roberto; Ravaja, Niklas; Kaipainen, Mauri; Takala, Tapio

2012-01-01

We outline general theoretical and practical implications of what we promote as enactive cinema for the neuroscientific study of online socio-emotional interaction. In a real-time functional magnetic resonance imaging (rt-fMRI) setting, participants are immersed in cinematic experiences that simulate social situations. While viewing, their physiological reactions—including brain responses—are tracked, representing implicit and unconscious experiences of the on-going social situations. These reactions, in turn, are analyzed in real-time and fed back to modify the cinematic sequences they are viewing while being scanned. Due to the engaging cinematic content, the proposed setting focuses on living-by in terms of shared psycho-physiological epiphenomena of experience rather than active coping in terms of goal-oriented motor actions. It constitutes a means to parametrically modify stimuli that depict social situations and their broader environmental contexts. As an alternative to studying the variation of brain responses as a function of a priori fixed stimuli, this method can be applied to survey the range of stimuli that evoke similar responses across participants at particular brain regions of interest. PMID:23125829

Enactive cinema paves way for understanding complex real-time social interaction in neuroimaging experiments.

PubMed

Tikka, Pia; Väljamäe, Aleksander; de Borst, Aline W; Pugliese, Roberto; Ravaja, Niklas; Kaipainen, Mauri; Takala, Tapio

2012-01-01

We outline general theoretical and practical implications of what we promote as enactive cinema for the neuroscientific study of online socio-emotional interaction. In a real-time functional magnetic resonance imaging (rt-fMRI) setting, participants are immersed in cinematic experiences that simulate social situations. While viewing, their physiological reactions-including brain responses-are tracked, representing implicit and unconscious experiences of the on-going social situations. These reactions, in turn, are analyzed in real-time and fed back to modify the cinematic sequences they are viewing while being scanned. Due to the engaging cinematic content, the proposed setting focuses on living-by in terms of shared psycho-physiological epiphenomena of experience rather than active coping in terms of goal-oriented motor actions. It constitutes a means to parametrically modify stimuli that depict social situations and their broader environmental contexts. As an alternative to studying the variation of brain responses as a function of a priori fixed stimuli, this method can be applied to survey the range of stimuli that evoke similar responses across participants at particular brain regions of interest.

An improved RST approach for timely alert and Near Real Time monitoring of oil spill disasters by using AVHRR data

NASA Astrophysics Data System (ADS)

Grimaldi, C. S. L.; Casciello, D.; Coviello, I.; Lacava, T.; Pergola, N.; Tramutoli, V.

2011-05-01

Information acquired and provided in Near Real Time is fundamental in contributing to reduce the impact of different sea pollution sources on the maritime environment. Optical data acquired by sensors aboard meteorological satellites, thanks to their high temporal resolution as well as to their delivery policy, can be profitably used for a Near Real Time sea monitoring, provided that accurate and reliable methodologies for analysis and investigation are designed, implemented and fully assessed. In this paper, the results achieved by the application of an improved version of RST (Robust Satellite Technique) to oil spill detection and monitoring will be shown. In particular, thermal infrared data acquired by the NOAA-AVHRR (National Oceanic and Atmospheric Administration-Advanced Very High Resolution Radiometer) have been analyzed and a new RST-based change detection index applied to the case of the oil spills that occurred off the Kuwait and Saudi Arabian coasts in January 1991 and during the Lebanon War in July 2006. The results obtained, even in comparison with those achieved by other AVHRR-based techniques, confirm the unique performance of the proposed approach in automatically detecting the presence of oil spill with a high level of reliability and sensitivity. Moreover, the potential of the extension of the proposed technique to sensors onboard geostationary satellites will be discussed within the context of oil spill monitoring systems, integrating products generated by high temporal (optical) and high spatial (radar) resolution satellite systems.

A preamplification approach to GMO detection in processed foods.

PubMed

Del Gaudio, S; Cirillo, A; Di Bernardo, G; Galderisi, U; Cipollaro, M

2010-03-01

DNA is widely used as a target for GMO analysis because of its stability and high detectability. Real-time PCR is the method routinely used in most analytical laboratories due to its quantitative performance and great sensitivity. Accurate DNA detection and quantification is dependent on the specificity and sensitivity of the amplification protocol as well as on the quality and quantity of the DNA used in the PCR reaction. In order to enhance the sensitivity of real-time PCR and consequently expand the number of analyzable target genes, we applied a preamplification technique to processed foods where DNA can be present in low amounts and/or in degraded forms thereby affecting the reliability of qualitative and quantitative results. The preamplification procedure utilizes a pool of primers targeting genes of interest and is followed by real-time PCR reactions specific for each gene. An improvement of Ct values was found comparing preamplified vs. non-preamplified DNA. The strategy reported in the present study will be also applicable to other fields requiring quantitative DNA testing by real-time PCR.

Supporting Authentic Learning Contexts Beyond Classroom Walls

NASA Astrophysics Data System (ADS)

Herrington, Jan; Specht, Marcus; Brickell, Gwyn; Harper, Barry

At the classroom level, contexts for learning are often limited in the experiential component. Teachers and trainers feel overwhelmed by the difficulty of inventing authentic learning contexts, and creating tasks that truly reflect the way knowledge would be used in the real world (Herrington et al. 2004). However, there are growing numbers of examples of how such authentic learning environments are being used in schools, higher education, and professional development in a variety of contexts and discipline areas, such as in literacy education (Ferry et al. 2006), in physical activity fitness and health (Rice et al. 1999), in Indigenous education (Marshall et al. 2001), in evaluation (Agostinho 2006), in multimedia and ICT (Bennett et al. 2001), in literature (Fitzsimmons 2006), and in business writing (Pennell et al. 1997). Teachers and trainers who subscribe to this approach to learning can be very inventive in developing learner perceptions of authentic contexts, but often financial, situational and time constraints limit the experiential elements of authentic learning settings.

Clinical value of real time 3D sonohysterography and 2D sonohysterography in comparison to hysteroscopy with subsequent histopathological examination in perimenopausal women with abnormal uterine bleeding.

PubMed

Kowalczyk, Dariusz; Guzikowski, Wojciech; Więcek, Jacek; Sioma-Markowska, Urszula

2012-01-01

In many publications the transvaginal ultrasound is regarded as the first step to diagnose the cause of uterine bleeding in perimenopausal women. In order to improve the sensitivity and specificity of the conventional ultrasound physiological saline solution was administered to the uterine cavity and after expansion of its walls the interior uterine cavity was examined. And this procedure is called 2D sonohysterography (SIS 2D). By the ultrasound scanners which enable to get 3D real time image a spatial evaluation of the uterine cavity is possible. Clinical value of the real time 3D sonohysterography and 2D sonohysterography compared to hysteroscopy with histopathological examination in perimenopausal women. The study concerned a group of 97 perimenopausal women with abnormal uterine bleeding. In all of them after a standard transvaginal ultrasonography a catheter was inserted into the uterine cavity. After expansion of the uterine walls by administering about 10 ml of 0,9% saline solution the uterine cavity was examined by conventional sonohysterography. Then a 3D imaging mode was activated and the uterine interior was examined by real time 3D ultrasonography. The ultrasound results were verified by hysteroscopy, the endometrial lesions were removed and underwent a histopathological examination. In two cases the SIS examination was impossible because of uterine cervix atresion. In the rest of examined group the SIS 2D sensitivity and specificity came up to 72 and 96% respectively. In the group of SIS 3D the sensitivity and specificity reached 83 and 99% respectively. Adding SIS 3D, a minimally invasive method, to conventional sonohysterography improves the precision of diagnosis of endometrial pathology, allows to get three-dimensional image of the uterine cavity and enables examination of endometrial lesions. The diagnostic precision of this procedure is similar to the results achieved by hysteroscopy.

Rapid detection of Enterovirus and Coxsackievirus A10 by a TaqMan based duplex one-step real time RT-PCR assay.

PubMed

Chen, Jingfang; Zhang, Rusheng; Ou, Xinhua; Yao, Dong; Huang, Zheng; Li, Linzhi; Sun, Biancheng

2017-06-01

A TaqMan based duplex one-step real time RT-PCR (rRT-PCR) assay was developed for the rapid detection of Coxsackievirus A10 (CV-A10) and other enterovirus (EVs) in clinical samples. The assay was fully evaluated and found to be specific and sensitive. When applied in 115 clinical samples, a 100% diagnostic sensitivity in CV-A10 detection and 97.4% diagnostic sensitivity in other EVs were found. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Mobile Ecological Momentary Assessment Tool (devilSPARC) for Nutrition and Physical Activity Behaviors in College Students: A Validation Study.

PubMed

Bruening, Meg; van Woerden, Irene; Todd, Michael; Brennhofer, Stephanie; Laska, Melissa N; Dunton, Genevieve

2016-07-27

The majority of nutrition and physical activity assessments methods commonly used in scientific research are subject to recall and social desirability biases, which result in over- or under-reporting of behaviors. Real-time mobile-based ecological momentary assessments (mEMAs) may result in decreased measurement biases and minimize participant burden. The aim was to examine the validity of a mEMA methodology to assess dietary and physical activity levels compared to 24-hour dietary recalls and accelerometers. This study was a pilot test of the SPARC (Social impact of Physical Activity and nutRition in College) study, which aimed to determine the mechanism by which friendship networks impact weight-related behaviors among young people. An mEMA app, devilSPARC, was developed to assess weight-related behaviors in real time. A diverse sample of 109 freshmen and community mentors attending a large southwestern university downloaded the devilSPARC mEMA app onto their personal mobile phones. Participants were prompted randomly eight times per day over the course of 4 days to complete mEMAs. During the same 4-day period, participants completed up to three 24-hour dietary recalls and/or 4 days of accelerometry. Self-reported mEMA responses were compared to 24-hour dietary recalls and accelerometry measures using comparison statistics, such as match rate, sensitivity and specificity, and mixed model odds ratios, adjusted for within-person correlation among repeated measurements. At the day level, total dietary intake data reported through the mEMA app reflected eating choices also captured by the 24-hour recall. Entrées had the lowest match rate, and fruits and vegetables had the highest match rate. Widening the window of aggregation of 24-hour dietary recall data on either side of the mEMA response resulted in increased specificity and decreased sensitivity. For physical activity behaviors, levels of activity reported through mEMA differed for sedentary versus non-sedentary activity at the day level as measured by accelerometers. The devilSPARC mEMA app is valid for assessing eating behaviors and the presence of sedentary activity at the day level. This mEMA may be useful in studies examining real-time weight-related behaviors.

Parallel-distributed mobile robot simulator

NASA Astrophysics Data System (ADS)

Okada, Hiroyuki; Sekiguchi, Minoru; Watanabe, Nobuo

1996-06-01

The aim of this project is to achieve an autonomous learning and growth function based on active interaction with the real world. It should also be able to autonomically acquire knowledge about the context in which jobs take place, and how the jobs are executed. This article describes a parallel distributed movable robot system simulator with an autonomous learning and growth function. The autonomous learning and growth function which we are proposing is characterized by its ability to learn and grow through interaction with the real world. When the movable robot interacts with the real world, the system compares the virtual environment simulation with the interaction result in the real world. The system then improves the virtual environment to match the real-world result more closely. This the system learns and grows. It is very important that such a simulation is time- realistic. The parallel distributed movable robot simulator was developed to simulate the space of a movable robot system with an autonomous learning and growth function. The simulator constructs a virtual space faithful to the real world and also integrates the interfaces between the user, the actual movable robot and the virtual movable robot. Using an ultrafast CG (computer graphics) system (FUJITSU AG series), time-realistic 3D CG is displayed.

Introducing Undergraduate Students to Real-Time PCR

ERIC Educational Resources Information Center

Hancock, Dale; Funnell, Alister; Jack, Briony; Johnston, Jill

2010-01-01

An experiment is conducted, which in four 3 h laboratory sessions, introduces third year undergraduate Biochemistry students to the technique of real-time PCR in a biological context. The model used is a murine erythroleukemia cell line (MEL cells). These continuously cycling, immature red blood cells, arrested at an early stage in erythropoiesis,…

Novel Acoustic Techniques for Assessing Fish Schooling in the Context of an Operational Ocean Observatory

DTIC Science & Technology

2007-09-30

Observing System (NJ SOS), which provides real-time data throughout the Mid-Atlantic Bight (MAB). The surveys will be positioned adaptively using real-time... gastropod were located during a 2-day period. These aggregations were remarkablystrong scatterers at frequencies ranging from 38-200 kHz. Data

Novel Acoustic Techniques for Assessing Fish Schooling in the Context of an Operational Ocean Observatory

DTIC Science & Technology

2008-01-01

which provides real-time data throughout the Mid-Atlantic Bight (MAB). The surveys will be positioned adaptively using real-time data collected with the...source was identified during the experiment as dense, monotypic aggregations of a pelagic gastropod were located during a 2-day period. These

Novel Acoustic Techniques for Assessing Fish Schooling in the Context of an Operational Ocean Observatory

DTIC Science & Technology

2007-09-30

which provides real-time data throughout the Mid-Atlantic Bight (MAB). The surveys will be positioned adaptively using real-time data collected with...scattering source was identified during the experiment as dense, monotypic aggregations of a pelagic gastropod were located during a 2-day period. These

A nested real-time PCR assay for the quantification of Plasmodium falciparum DNA extracted from dried blood spots.

PubMed

Tran, Tuan M; Aghili, Amirali; Li, Shanping; Ongoiba, Aissata; Kayentao, Kassoum; Doumbo, Safiatou; Traore, Boubacar; Crompton, Peter D

2014-10-04

As public health efforts seek to eradicate malaria, there has been an emphasis on eliminating low-density parasite reservoirs in asymptomatic carriers. As such, diagnosing submicroscopic Plasmodium infections using PCR-based techniques has become important not only in clinical trials of malaria vaccines and therapeutics, but also in active malaria surveillance campaigns. However, PCR-based quantitative assays that rely on nucleic acid extracted from dried blood spots (DBS) have demonstrated lower sensitivity than assays that use cryopreserved whole blood as source material. The density of Plasmodium falciparum asexual parasites was quantified using genomic DNA extracted from dried blood spots (DBS) and the sensitivity of two approaches was compared: quantitative real-time PCR (qPCR) targeting the P. falciparum 18S ribosomal RNA gene, either with an initial conventional PCR amplification prior to qPCR (nested qPCR), or without an initial amplification (qPCR only). Parasite densities determined by nested qPCR, qPCR only, and light microscopy were compared. Nested qPCR results in 10-fold higher sensitivity (0.5 parasites/μl) when compared to qPCR only (five parasites/ul). Among microscopy-positive samples, parasite densities calculated by nested qPCR correlated strongly with microscopy for both asymptomatic (Pearson's r=0.58, P<0.001) and symptomatic (Pearson's r=0.70, P<0.0001) P. falciparum infections. Nested qPCR improves the sensitivity for the detection of P. falciparum blood-stage infection from clinical DBS samples. This approach may be useful for active malaria surveillance in areas where submicroscopic asymptomatic infections are prevalent.

Supporting Collective Inquiry: A Technology Framework for Distributed Learning

NASA Astrophysics Data System (ADS)

Tissenbaum, Michael

This design-based study describes the implementation and evaluation of a technology framework to support smart classrooms and Distributed Technology Enhanced Learning (DTEL) called SAIL Smart Space (S3). S3 is an open-source technology framework designed to support students engaged in inquiry investigations as a knowledge community. To evaluate the effectiveness of S3 as a generalizable technology framework, a curriculum named PLACE (Physics Learning Across Contexts and Environments) was developed to support two grade-11 physics classes (n = 22; n = 23) engaged in a multi-context inquiry curriculum based on the Knowledge Community and Inquiry (KCI) pedagogical model. This dissertation outlines three initial design studies that established a set of design principles for DTEL curricula, and related technology infrastructures. These principles guided the development of PLACE, a twelve-week inquiry curriculum in which students drew upon their community-generated knowledge base as a source of evidence for solving ill-structured physics problems based on the physics of Hollywood movies. During the culminating smart classroom activity, the S3 framework played a central role in orchestrating student activities, including managing the flow of materials and students using real-time data mining and intelligent agents that responded to emergent class patterns. S3 supported students' construction of knowledge through the use individual, collective and collaborative scripts and technologies, including tablets and interactive large-format displays. Aggregate and real-time ambient visualizations helped the teacher act as a wondering facilitator, supporting students in their inquiry where needed. A teacher orchestration tablet gave the teacher some control over the flow of the scripted activities, and alerted him to critical moments for intervention. Analysis focuses on S3's effectiveness in supporting students' inquiry across multiple learning contexts and scales of time, and in making timely and effective use of the community's knowledge base, towards producing solutions to sophisticated, ill defined problems in the domain of physics. Video analysis examined whether S3 supported teacher orchestration, freeing him to focus less on classroom management and more on students' inquiry. Three important outcomes of this research are a set of design principles for DTEL environments, a specific technology infrastructure (S3), and a DTEL research framework.

Sequence Optimized Real-Time RT-PCR Assay for Detection of Crimean-Congo Hemorrhagic Fever Virus

DTIC Science & Technology

2017-03-21

19-23]. Real-56 time reverse-transcription PCR remains the gold standard for quantitative , sensitive, and specific 57 detection of CCHFV; however...five-fold in two different series , and samples were run by real- time RT-PCR 116 in triplicate. The preliminary LOD was the lowest RNA dilution where...1 Sequence optimized real- time RT-PCR assay for detection of Crimean-Congo hemorrhagic fever 1 virus 2 3 JW Koehler1, KL Delp1, AT Hall1, SP

Distinguishing the Time Course of Lexical and Discourse Processes through Context, Coreference, and Quantified Expressions

ERIC Educational Resources Information Center

Huang, Yi Ting; Gordon, Peter C.

2011-01-01

How does prior context influence lexical and discourse-level processing during real-time language comprehension? Experiment 1 examined whether the referential ambiguity introduced by a repeated, anaphoric expression had an immediate or delayed effect on lexical and discourse processing, using an eye-tracking-while-reading task. Eye movements…

Evaluation of a new single-tube multiprobe real-time PCR for diagnosis of Entamoeba histolytica and Entamoeba dispar.

PubMed

Liang, Shih-Yu; Hsia, Kan-Tai; Chan, Yun-Hsien; Fan, Chia-Kwung; Jiang, Donald Dah-Shyong; Landt, Olfert; Ji, Dar-Der

2010-08-01

A single-tube multiprobe real-time PCR assay for simultaneous detection of Entamoeba histolytica and Entamoeba dispar was developed. One primer pair with 2 species-specific probes was designed based on new SSU RNA regions of the ribosomal DNA-containing episome. The sensitivity is 1 parasite per milliliter of feces and thus superior to the conventional nested PCR and comparable to other published real-time PCR protocols. The applicability for clinical diagnosis was validated with 218 stool specimens from patients. A total of 51 E. histolytica and 39 E. dispar positive samples was detected by the multiprobe real-time PCR compared to 39 and 22 by routine nested PCR diagnosis. The detection rate of Entamoeba species for the multiprobe real-time PCR assays was significantly higher than the nested PCR (40.8% vs. 28.0%, P < 0.01). The test did not show cross reactivity with DNA from Entamoeba moshkovskii, Giardia lamblia , Cryptosporidium sp., Escherichia coli , or other nonpathogenic enteric parasites. The multiprobe real-time PCR assay is simple and rapid and has high specificity and sensitivity. The assay could streamline the laboratory diagnosis procedure and facilitate epidemiological investigation.

The AGN-Starburst connection in COLA galaxies

NASA Astrophysics Data System (ADS)

Hurley, Rossa; Phillips, Chris; Norris, Ray; Appleton, Phil; Conway, John; Parra, Rodrigo

2007-10-01

We propose to observe the COLA-S sample of 107 galaxies to test the hypothesis that VLBI-detectable AGN cores in IR-luminous sources are accompanied by intense compact star-formation activity. To maximise our sensitivity with available resources, we propose single-baseline 1 Gbit/s VLBI observations between Narrabri and Parkes, and will correlate the data in near-real time using the CPSR-II computer at Parkes.

Real-time monitoring of disintegration activity of catalytic core domain of HIV-1 integrase using molecular beacon.

PubMed

Zhang, Da-wei; Zhao, Ming-ming; He, Hong-qiu; Guo, Shun-xing

2013-09-15

HIV-1 integrase, an essential enzyme for retroviral replication, is a validated target for anti-HIV therapy development. The catalytic core domain of integrase (IN-CCD) is capable of catalyzing disintegration reaction. In this work, a hairpin-shaped disintegration substrate was designed and validated by enzyme-linked immunosorbent assay; a molecular beacon-based assay was developed for disintegration reaction of IN-CCD. Results showed that the disintegration substrate could be recognized and catalyzed by IN-CCD, and the disintegration reaction can be monitored according to the increase of fluorescent signal. The assay can be applied to real-time detection of disintegration with advantages of simplicity, high sensitivity, and excellent specificity. Copyright © 2013 Elsevier Inc. All rights reserved.

Applying predictive analytics to develop an intelligent risk detection application for healthcare contexts.

PubMed

Moghimi, Fatemeh Hoda; Cheung, Michael; Wickramasinghe, Nilmini

2013-01-01

Healthcare is an information rich industry where successful outcomes require the processing of multi-spectral data and sound decision making. The exponential growth of data and big data issues coupled with a rapid increase of service demands in healthcare contexts today, requires a robust framework enabled by IT (information technology) solutions as well as real-time service handling in order to ensure superior decision making and successful healthcare outcomes. Such a context is appropriate for the application of real time intelligent risk detection decision support systems using predictive analytic techniques such as data mining. To illustrate the power and potential of data science technologies in healthcare decision making scenarios, the use of an intelligent risk detection (IRD) model is proffered for the context of Congenital Heart Disease (CHD) in children, an area which requires complex high risk decisions that need to be made expeditiously and accurately in order to ensure successful healthcare outcomes.

A high sensitivity real-time NVR monitor. [Nonvolatile Residue

NASA Technical Reports Server (NTRS)

Bowers, William D.; Chuan, R. L.

1992-01-01

The use of a temperature-controlled 200-MHz SAW resonator piezoelectric mass microbalance to monitor the mass of nonvolatile residue (NVR) deposited on its surface in real time is reported. The fundamental frequency of this device is mainly dependent on the configuration of the transducers and not on the thickness of the substrate. Therefore, higher operating frequencies can be achieved without reducing the thickness of the crystal. The real-time instrument was integrated onto a conventional stainless steel NVR plate and operated flawlessly over a 14-d period at Kennedy Space Center and successfully measured less than 1 ng/sq cm d NVR contamination. Contamination episodes detected by the instrument were correlated with scheduled activities on the test stand. Under the assumption of a baseline noise level of +/- 2 Hz, the absolute mass lower limit of detection would be 0.065 ng/sq cm. This would enable the detection of a daily NVR deposition rate of less than 0.1 ng/sq cm d.

Reliability of Fitness Tests Using Methods and Time Periods Common in Sport and Occupational Management

PubMed Central

Burnstein, Bryan D.; Steele, Russell J.; Shrier, Ian

2011-01-01

Context: Fitness testing is used frequently in many areas of physical activity, but the reliability of these measurements under real-world, practical conditions is unknown. Objective: To evaluate the reliability of specific fitness tests using the methods and time periods used in the context of real-world sport and occupational management. Design: Cohort study. Setting: Eighteen different Cirque du Soleil shows. Patients or Other Participants: Cirque du Soleil physical performers who completed 4 consecutive tests (6-month intervals) and were free of injury or illness at each session (n = 238 of 701 physical performers). Intervention(s): Performers completed 6 fitness tests on each assessment date: dynamic balance, Harvard step test, handgrip, vertical jump, pull-ups, and 60-second jump test. Main Outcome Measure(s): We calculated the intraclass coefficient (ICC) and limits of agreement between baseline and each time point and the ICC over all 4 time points combined. Results: Reliability was acceptable (ICC > 0.6) over an 18-month time period for all pairwise comparisons and all time points together for the handgrip, vertical jump, and pull-up assessments. The Harvard step test and 60-second jump test had poor reliability (ICC < 0.6) between baseline and other time points. When we excluded the baseline data and calculated the ICC for 6-month, 12-month, and 18-month time points, both the Harvard step test and 60-second jump test demonstrated acceptable reliability. Dynamic balance was unreliable in all contexts. Limit-of-agreement analysis demonstrated considerable intraindividual variability for some tests and a learning effect by administrators on others. Conclusions: Five of the 6 tests in this battery had acceptable reliability over an 18-month time frame, but the values for certain individuals may vary considerably from time to time for some tests. Specific tests may require a learning period for administrators. PMID:22488138

Handling Real-World Context Awareness, Uncertainty and Vagueness in Real-Time Human Activity Tracking and Recognition with a Fuzzy Ontology-Based Hybrid Method

PubMed Central

Díaz-Rodríguez, Natalia; Cadahía, Olmo León; Cuéllar, Manuel Pegalajar; Lilius, Johan; Calvo-Flores, Miguel Delgado

2014-01-01

Human activity recognition is a key task in ambient intelligence applications to achieve proper ambient assisted living. There has been remarkable progress in this domain, but some challenges still remain to obtain robust methods. Our goal in this work is to provide a system that allows the modeling and recognition of a set of complex activities in real life scenarios involving interaction with the environment. The proposed framework is a hybrid model that comprises two main modules: a low level sub-activity recognizer, based on data-driven methods, and a high-level activity recognizer, implemented with a fuzzy ontology to include the semantic interpretation of actions performed by users. The fuzzy ontology is fed by the sub-activities recognized by the low level data-driven component and provides fuzzy ontological reasoning to recognize both the activities and their influence in the environment with semantics. An additional benefit of the approach is the ability to handle vagueness and uncertainty in the knowledge-based module, which substantially outperforms the treatment of incomplete and/or imprecise data with respect to classic crisp ontologies. We validate these advantages with the public CAD-120 dataset (Cornell Activity Dataset), achieving an accuracy of 90.1% and 91.07% for low-level and high-level activities, respectively. This entails an improvement over fully data-driven or ontology-based approaches. PMID:25268914

From Numbers to Letters: Feedback Regularization in Visual Word Recognition

ERIC Educational Resources Information Center

Molinaro, Nicola; Dunabeitia, Jon Andoni; Marin-Gutierrez, Alejandro; Carreiras, Manuel

2010-01-01

Word reading in alphabetic languages involves letter identification, independently of the format in which these letters are written. This process of letter "regularization" is sensitive to word context, leading to the recognition of a word even when numbers that resemble letters are inserted among other real letters (e.g., M4TERI4L). The present…

Optimization of active distribution networks: Design and analysis of significative case studies for enabling control actions of real infrastructure

NASA Astrophysics Data System (ADS)

Moneta, Diana; Mora, Paolo; Viganò, Giacomo; Alimonti, Gianluca

2014-12-01

The diffusion of Distributed Generation (DG) based on Renewable Energy Sources (RES) requires new strategies to ensure reliable and economic operation of the distribution networks and to support the diffusion of DG itself. An advanced algorithm (DISCoVER - DIStribution Company VoltagE Regulator) is being developed to optimize the operation of active network by means of an advanced voltage control based on several regulations. Starting from forecasted load and generation, real on-field measurements, technical constraints and costs for each resource, the algorithm generates for each time period a set of commands for controllable resources that guarantees achievement of technical goals minimizing the overall cost. Before integrating the controller into the telecontrol system of the real networks, and in order to validate the proper behaviour of the algorithm and to identify possible critical conditions, a complete simulation phase has started. The first step is concerning the definition of a wide range of "case studies", that are the combination of network topology, technical constraints and targets, load and generation profiles and "costs" of resources that define a valid context to test the algorithm, with particular focus on battery and RES management. First results achieved from simulation activity on test networks (based on real MV grids) and actual battery characteristics are given, together with prospective performance on real case applications.

Effects of Context on Eye Movements When Reading About Possible and Impossible Events

PubMed Central

Warren, Tessa; McConnell, Kerry; Rayner, Keith

2009-01-01

Plausibility violations resulting in impossible scenarios lead to earlier and longer lasting eye movement disruption than violations resulting in highly unlikely scenarios (K. Rayner, T. Warren, B. J. Juhasz, & S. P. Liversedge, 2004; T. Warren & K. McConnell, 2007). This could reflect either differences in the timing of availability of different kinds of information (e.g., selectional restrictions, world knowledge, and context) or differences in their relative power to guide semantic interpretation. The authors investigated eye movements to possible and impossible events in real-world and fantasy contexts to determine when contextual information influences detection of impossibility cued by a semantic mismatch between a verb and an argument. Gaze durations on a target word were longer to impossible events independent of context. However, a measure of the time elapsed from first fixating the target word to moving past it showed disruption only in the real-world context. These results suggest that contextual information did not eliminate initial disruption but moderated it quickly thereafter. PMID:18605885

Multi-Level Pre-Correlation RFI Flagging for Real-Time Implementation on UniBoard

NASA Astrophysics Data System (ADS)

Dumez-Viou, Cédric; Weber, Rodolphe; Ravier, Philippe

2016-03-01

Because of the denser active use of the spectrum, and because of radio telescopes higher sensitivity, radio frequency interference (RFI) mitigation has become a sensitive topic for current and future radio telescope designs. Even if quite sophisticated approaches have been proposed in the recent years, the majority of RFI mitigation operational procedures are based on post-correlation corrupted data flagging. Moreover, given the huge amount of data delivered by current and next generation radio telescopes, all these RFI detection procedures have to be at least automatic and, if possible, real-time. In this paper, the implementation of a real-time pre-correlation RFI detection and flagging procedure into generic high-performance computing platforms based on field programmable gate arrays (FPGA) is described, simulated and tested. One of these boards, UniBoard, developed under a Joint Research Activity in the RadioNet FP7 European programme is based on eight FPGAs interconnected by a high speed transceiver mesh. It provides up to 4 TMACs with ®Altera Stratix IV FPGA and 160 Gbps data rate for the input data stream. The proposed concept is to continuously monitor the data quality at different stages in the digital preprocessing pipeline between the antennas and the correlator, at the station level and the core level. In this way, the detectors are applied at stages where different time-frequency resolutions can be achieved and where the interference-to-noise ratio (INR) is maximum right before any dilution of RFI characteristics by subsequent channelizations or signal recombinations. The detection decisions could be linked to a RFI statistics database or could be attached to the data for later stage flagging. Considering the high in-out data rate in the pre-correlation stages, only real-time and go-through detectors (i.e. no iterative processing) can be implemented. In this paper, a real-time and adaptive detection scheme is described. An ongoing case study has been set up with the Electronic Multi-Beam Radio Astronomy Concept (EMBRACE) radio telescope facility at Nançay Observatory. The objective is to evaluate the performances of this concept in term of hardware complexity, detection efficiency and additional RFI metadata rate cost. The UniBoard implementation scheme is described.

Subcellular real-time in vivo imaging of intralymphatic and intravascular cancer-cell trafficking

NASA Astrophysics Data System (ADS)

McElroy, M.; Hayashi, K.; Kaushal, S.; Bouvet, M.; Hoffman, Robert M.

2008-02-01

With the use of fluorescent cells labeled with green fluorescent protein (GFP) in the nucleus and red fluorescent protein (RFP) in the cytoplasm and a highly sensitive small animal imaging system with both macro-optics and micro-optics, we have developed subcellular real-time imaging of cancer cell trafficking in live mice. Dual-color cancer cells were injected by a vascular route in an abdominal skin flap in nude mice. The mice were imaged with an Olympus OV100 small animal imaging system with a sensitive CCD camera and four objective lenses, parcentered and parfocal, enabling imaging from macrocellular to subcellular. We observed the nuclear and cytoplasmic behavior of cancer cells in real time in blood vessels as they moved by various means or adhered to the vessel surface in the abdominal skin flap. During extravasation, real-time dual-color imaging showed that cytoplasmic processes of the cancer cells exited the vessels first, with nuclei following along the cytoplasmic projections. Both cytoplasm and nuclei underwent deformation during extravasation. Different cancer cell lines seemed to strongly vary in their ability to extravasate. We have also developed real-time imaging of cancer cell trafficking in lymphatic vessels. Cancer cells labeled with GFP and/or RFP were injected into the inguinal lymph node of nude mice. The labeled cancer cells trafficked through lymphatic vessels where they were imaged via a skin flap in real-time at the cellular level until they entered the axillary lymph node. The bright dual-color fluorescence of the cancer cells and the real-time microscopic imaging capability of the Olympus OV100 enabled imaging the trafficking cancer cells in both blood vessels and lymphatics. With the dual-color cancer cells and the highly sensitive imaging system described here, the subcellular dynamics of cancer metastasis can now be observed in live mice in real time.

Real-time Fatigue and Free-Living Physical Activity in Hematopoietic Stem Cell Transplantation Cancer Survivors and Healthy Controls: A Preliminary Examination of the Temporal, Dynamic Relationship.

PubMed

Hacker, Eileen Danaher; Kim, Inah; Park, Chang; Peters, Tara

Fatigue and physical inactivity, critical problems facing cancer survivors, impact overall health and functioning. Our group designed a novel methodology to evaluate the temporal, dynamic patterns in real-world settings. Using real-time technology, the temporal, dynamic relationship between real-time fatigue and free-living is described and compared in cancer survivors who were treated with hematopoietic stem cell transplantation (n = 25) and age- and gender-matched healthy controls (n = 25). Subjects wore wrist actigraphs on their nondominant hand to assess free-living physical activity, measured in 1-minute epochs, over 7 days. Subjects entered real-time fatigue assessments directly into the subjective event marker of the actigraph 5 times per day. Running averages of mean 1-minute activity counts 30, 60, and 120 minutes before and after each real-time fatigue score were correlated with real-time fatigue using generalized estimating equations, RESULTS:: A strong inverse relationship exists between real-time fatigue and subsequent free-living physical activity. This inverse relationship suggests that increasing real-time fatigue limits subsequent physical activity (B range= -0.002 to -0.004; P < .001). No significant differences in the dynamic patterns of real-time fatigue and free-living physical activity were found between groups. To our knowledge, this is the first study to document the temporal and potentially causal relationship between real-time fatigue and free-living physical activity in real-world setting. These findings suggest that fatigue drives the subsequent physical activity and the relationship may not be bidirectional. Understanding the temporal, dynamic relationship may have important health implications for developing interventions to address fatigue in cancer survivors.

Reward and punishment learning in daily life: A replication study.

PubMed

Heininga, Vera E; van Roekel, Eeske; Wichers, Marieke; Oldehinkel, Albertine J

2017-01-01

Day-to-day experiences are accompanied by feelings of Positive Affect (PA) and Negative Affect (NA). Implicitly, without conscious processing, individuals learn about the reward and punishment value of each context and activity. These associative learning processes, in turn, affect the probability that individuals will re-engage in such activities or seek out that context. So far, implicit learning processes are almost exclusively investigated in controlled laboratory settings and not in daily life. Here we aimed to replicate the first study that investigated implicit learning processes in real life, by means of the Experience Sampling Method (ESM). That is, using an experience-sampling study with 90 time points (three measurements over 30 days), we prospectively measured time spent in social company and amount of physical activity as well as PA and NA in the daily lives of 18-24-year-old young adults (n = 69 with anhedonia, n = 69 without anhedonia). Multilevel analyses showed a punishment learning effect with regard to time spent in company of friends, but not a reward learning effect. Neither reward nor punishment learning effects were found with regard to physical activity. Our study shows promising results for future research on implicit learning processes in daily life, with the proviso of careful consideration of the timescale used. Short-term retrospective ESM design with beeps approximately six hours apart may suffer from mismatch noise that hampers accurate detection of associative learning effects over time.

A FRET-Based Real-Time PCR Assay to Identify the Main Causal Agents of New World Tegumentary Leishmaniasis

PubMed Central

De Los Santos, Maxy; Soberón, Valeria; Lucas, Carmen M.; Matlashewski, Greg; Llanos-Cuentas, Alejandro; Ore, Marianela; Baldeviano, G. Christian; Edgel, Kimberly A.; Lescano, Andres G.; Graf, Paul C. F.; Bacon, David J.

2013-01-01

In South America, various species of Leishmania are endemic and cause New World tegumentary leishmaniasis (NWTL). The correct identification of these species is critical for adequate clinical management and surveillance activities. We developed a real-time polymerase chain reaction (PCR) assay and evaluated its diagnostic performance using 64 archived parasite isolates and 192 prospectively identified samples collected from individuals with suspected leishmaniasis enrolled at two reference clinics in Lima, Peru. The real-time PCR assay was able to detect a single parasite and provided unambiguous melting peaks for five Leishmania species of the Viannia subgenus that are highly prevalent in South America: L. (V.) braziliensis, L. (V.) panamensis, L. (V.) guyanensis, L. (V.) peruviana and L. (V.) lainsoni. Using kinetoplastid DNA-based PCR as a gold standard, the real-time PCR had sensitivity and specificity values of 92% and 77%, respectively, which were significantly higher than those of conventional tests such as microscopy, culture and the leishmanin skin test (LST). In addition, the real-time PCR identified 147 different clinical samples at the species level, providing an overall agreement of 100% when compared to multilocus sequence typing (MLST) data performed on a subset of these samples. Furthermore, the real-time PCR was three times faster and five times less expensive when compared to PCR - MLST for species identification from clinical specimens. In summary, this new assay represents a cost-effective and reliable alternative for the identification of the main species causing NWTL in South America. PMID:23301111

Comparative diagnostic evaluation of OMP31 gene based TaqMan® real-time PCR assay with visual LAMP assay and indirect ELISA for caprine brucellosis.

PubMed

Saini, Suman; Gupta, V K; Gururaj, K; Singh, D D; Pawaiya, R V S; Gangwar, N K; Mishra, A K; Dwivedi, Deepak; Andani, Dimple; Kumar, Ashok; Goswami, T K

2017-08-01

Brucellosis is one of the leading causes of abortion in domestic animals that imposes costs on both economy and society. The disease is highly zoonotic and poses risk to animal handlers due to its zoonotic nature. It causes stillbirth, loss of kids and abortion in last term of pregnancy. Reproductive damage includes infertility in does and orchitis and epididymitis in breeding bucks, which result in high financial losses to farmers and the agriculture industry as a whole. It requires highly sensitive and specific assays to diagnose the disease at field level. In the current study, a visual loop-mediated isothermal amplification (LAMP) assay and the TaqMan® real-time PCR were developed with high sensitivity and specificity. For the TaqMan® probe, real-time PCR primers were developed using Omp31 gene as target and primers were designed using discontiguous conserved sequences of Omp31 gene. The Omp31 probes were designed by attaching 6-FAM reporter dye at the 5' end and BHQ-1 quencher at the 3' end. Published primers were used for visual LAMP assay targeting the Omp25 gene. Sensitivity of the standardized visual LAMP assay and TaqMan® real-time PCR assay was determined by serial dilution of positive Brucella melitensis DNA (10 2 to 10 -4  ng) obtained from standard culture. The TaqMan® probe real-time assay can detect as low as 100 fg of B. melitensis DNA, whereas culture from vaginal swab washings has a limit of detection (LOD) of only 1 cfu/ml. Similarly, the visual LAMP assay can detect as low as 10 fg of B. melitensis DNA as compared to an LOD of 30 cfu/ml from culture of vaginal swab washings. Both assays were compared with serological tests (serum tube agglutination test (STAT) and indirect enzyme-linked immunosorbent assay (iELISA)) for diagnostic sensitivity and specificity. Diagnostic sensitivities and specificities for TaqMan® real-time PCR vs. LAMP assays were 98 and 100% vs. 100 and 97.8%, respectively. Results of visual LAMP assay indicated that LAMP is a fast, specific, sensitive, inexpensive and suitable method for diagnosis of B. melitensis infection under field conditions. On the other hand, Omp31 TaqMan® probe real-time assay can be used in conjunction with the other field-based diagnostic tests due to its high specificity.

Investigation of diseases through red blood cells' shape using photoacoustic response technique

NASA Astrophysics Data System (ADS)

Biswas, Deblina; Gorey, Abhijeet; Chen, Goerge C. K.; Sharma, Norman; Vasudevan, Srivathsan

2015-03-01

Photoacoustic (PA) imaging is a non-invasive real-time technique, widely applied to many biomedical imaging studies in the recent years. While most of these studies have been focussed on obtaining an image after reconstruction, various features of time domain signal (e.g. amplitude, width, rise and relaxation time) would provide very high sensitivity in detecting morphological changes in cells during a biological study. Different haematological disorders (e.g., sickle cell anaemia, thalassemia) exhibit significant morphological cellular changes. In this context, this study explores the possibility of utilizing the developed photoacoustic response technique to apply onto blood samples. Results of our preliminary study demonstrate that there is a significant change in signal amplitude due to change in concentration of the blood. Thus it shows the sensitivity of the developed photoacoustic technique towards red blood cell count (related to haematological disease like anaemia). Subsequently, morphological changes in RBC (i.e. swollen and shrunk compared to normal RBC) induced by hypotonic and hypertonic solutions respectively were also experimented. The result shows a distinct change in PA signal amplitude. This would serve as a diagnostic signature for many future studies on cellular morphological disorders.

Bridging FPGA and GPU technologies for AO real-time control

NASA Astrophysics Data System (ADS)

Perret, Denis; Lainé, Maxime; Bernard, Julien; Gratadour, Damien; Sevin, Arnaud

2016-07-01

Our team has developed a common environment for high performance simulations and real-time control of AO systems based on the use of Graphics Processors Units in the context of the COMPASS project. Such a solution, based on the ability of the real time core in the simulation to provide adequate computing performance, limits the cost of developing AO RTC systems and makes them more scalable. A code developed and validated in the context of the simulation may be injected directly into the system and tested on sky. Furthermore, the use of relatively low cost components also offers significant advantages for the system hardware platform. However, the use of GPUs in an AO loop comes with drawbacks: the traditional way of offloading computation from CPU to GPUs - involving multiple copies and unacceptable overhead in kernel launching - is not well suited in a real time context. This last application requires the implementation of a solution enabling direct memory access (DMA) to the GPU memory from a third party device, bypassing the operating system. This allows this device to communicate directly with the real-time core of the simulation feeding it with the WFS camera pixel stream. We show that DMA between a custom FPGA-based frame-grabber and a computation unit (GPU, FPGA, or Coprocessor such as Xeon-phi) across PCIe allows us to get latencies compatible with what will be needed on ELTs. As a fine-grained synchronization mechanism is not yet made available by GPU vendors, we propose the use of memory polling to avoid interrupts handling and involvement of a CPU. Network and Vision protocols are handled by the FPGA-based Network Interface Card (NIC). We present the results we obtained on a complete AO loop using camera and deformable mirror simulators.

Real-time fMRI: a tool for local brain regulation.

PubMed

Caria, Andrea; Sitaram, Ranganatha; Birbaumer, Niels

2012-10-01

Real-time fMRI permits simultaneous measurement and observation of brain activity during an ongoing task. One of the most challenging applications of real-time fMRI in neuroscientific and clinical research is the possibility of acquiring volitional control of localized brain activity using real-time fMRI-based neurofeedback protocols. Real-time fMRI allows the experimenter to noninvasively manipulate brain activity as an independent variable to observe the effects on behavior. Real-time fMRI neurofeedback studies demonstrated that learned control of the local brain activity leads to specific changes in behavior. Here, the authors describe the implementation and application of real-time fMRI with particular emphasis on the self-regulation of local brain activity and the investigation of brain-function relationships. Real-time fMRI represents a promising new approach to cognitive neuroscience that could complement traditional neuroimaging techniques by providing more causal insights into the functional role of circumscribed brain regions in behavior.

Hard Real-Time: C++ Versus RTSJ

NASA Technical Reports Server (NTRS)

Dvorak, Daniel L.; Reinholtz, William K.

2004-01-01

In the domain of hard real-time systems, which language is better: C++ or the Real-Time Specification for Java (RTSJ)? Although ordinary Java provides a more productive programming environment than C++ due to its automatic memory management, that benefit does not apply to RTSJ when using NoHeapRealtimeThread and non-heap memory areas. As a result, RTSJ programmers must manage non-heap memory explicitly. While that's not a deterrent for veteran real-time programmers-where explicit memory management is common-the lack of certain language features in RTSJ (and Java) makes that manual memory management harder to accomplish safely than in C++. This paper illustrates the problem for practitioners in the context of moving data and managing memory in a real-time producer/consumer pattern. The relative ease of implementation and safety of the C++ programming model suggests that RTSJ has a struggle ahead in the domain of hard real-time applications, despite its other attractive features.

HRT-UML: a design method for hard real-time systems based on the UML notation

NASA Astrophysics Data System (ADS)

D'Alessandro, Massimo; Mazzini, Silvia; di Natale, Marco; Lipari, Giuseppe

2002-07-01

The Hard Real-Time-Unified Modelling Language (HRT-UML) method aims at providing a comprehensive solution to the modeling of Hard Real Time systems. The experience shows that the design of Hard Real-Time systems needs methodologies suitable for the modeling and analysis of aspects related to time, schedulability and performance. In the context of the European Aerospace community a reference method for design is Hierarchical Object Oriented Design (HOOD) and in particular its extension for the modeling of hard real time systems, Hard Real-Time-Hierarchical Object Oriented Design (HRT-HOOD), recommended by the European Space Agency (ESA) for the development of on-board systems. On the other hand in recent years the Unified Modelling Language (UML) has been gaining a very large acceptance in a wide range of domains, all over the world, becoming a de-facto international standard. Tool vendors are very active in this potentially big market. In the Aerospace domain the common opinion is that UML, as a general notation, is not suitable for Hard Real Time systems, even if its importance is recognized as a standard and as a technological trend in the near future. These considerations suggest the possibility of replacing the HRT-HOOD method with a customized version of UML, that incorporates the advantages of both standards and complements the weak points. This approach has the clear advantage of making HRT-HOOD converge on a more powerful and expressive modeling notation. The paper identifies a mapping of the HRT-HOOD semantics into the UML one, and proposes a UML extension profile, that we call HRT-UML, based on the UML standard extension mechanisms, to fully represent HRT-HOOD design concepts. Finally it discusses the relationships between our profile and the UML profile for schedulability, performance and time, adopted by OMG in November 2001.

Development of an isothermal recombinase polymerase amplification assay for rapid detection of pseudorabies virus.

PubMed

Yang, Yang; Qin, Xiaodong; Zhang, Wei; Li, Zhiyong; Zhang, Shuaijun; Li, Yanmin; Zhang, Zhidong

2017-06-01

Recombinase polymerase amplification assays using real-time fluorescent detection (real-time RPA assay) and lateral flow dipstick (RPA LFD assay) were developed targeting the gD gene of pseudorabies virus (PRV). Both assays were performed at 39 °C within 20 min. The sensitivity of the real-time RPA assay and the RPA LFD assay was 100 copies per reaction and 160 copies per reaction, respectively. Both assays did not detect DNAs from other virus or PRV negative samples. Therefore, the developed RPA assays provide a rapid, simple, sensitive and specific alternative tool for detection of PRV. Copyright © 2017. Published by Elsevier Ltd.

The linguistic context effects on the processing of body-object interaction words: An ERP study on second language learners.

PubMed

Xue, Jin; Marmolejo-Ramos, Fernando; Pei, Xuna

2015-07-10

Embodied theories of cognition argue that the processing of both concrete and abstract concepts requires the activation of sensorimotor systems. The present study examined the time course for embedding a sensorimotor context in order to elicit sensitivity to the sensorimotor consequences of understanding body-object interaction (BOI) words. In the study, Event-Related Potentials (ERPs) were recorded while subjects performed a sentence acceptability task. Target BOI words were preceded by rich or poor sensorimotor sentential contexts. The behavioural results replicated previous findings in that high BOI words received a response faster than low BOI words. In addition to this, however, there was a context effect in the sensorimotor region as well as a BOI effect in the parietal region (involved in object representation). The results indicate that the sentential sensorimotor context contributes to the subsequent BOI processing and that action-and perception-related language leads to the activation of the same brain areas, which is consistent with the embodiment theory. Copyright © 2015 Elsevier B.V. All rights reserved.

Do pain-associated contexts increase pain sensitivity? An investigation using virtual reality.

PubMed

Harvie, Daniel S; Sterling, Michele; Smith, Ashley D

2018-04-30

Pain is not a linear result of nociception, but is dependent on multisensory inputs, psychological factors, and prior experience. Since nociceptive models appear insufficient to explain chronic pain, understanding non-nociceptive contributors is imperative. Several recent models propose that cues associatively linked to painful events might acquire the capacity to augment, or even cause, pain. This experiment aimed to determine whether contexts associated with pain, could modulate mechanical pain thresholds and pain intensity. Forty-eight healthy participants underwent a contextual conditioning procedure, where three neutral virtual reality contexts were paired with either unpredictable noxious stimulation, unpredictable vibrotactile stimulation, or no stimulation. Following the conditioning procedure, mechanical pain thresholds and pain evoked by a test stimulus were examined in each context. In the test phase, the effect of expectancy was equalised across conditions by informing participants when thresholds and painful stimuli would be presented. Contrary to our hypothesis, scenes that were associated with noxious stimulation did not increase mechanical sensitivity (p=0.08), or increase pain intensity (p=0.46). However, an interaction with sex highlighted the possibility that pain-associated contexts may alter pain sensitivity in females but not males (p=0.03). Overall, our data does not support the idea that pain-associated contexts can alter pain sensitivity in healthy asymptomatic individuals. That an effect was shown in females highlights the possibility that some subgroups may be susceptible to such an effect, although the magnitude of the effect may lack real-world significance. If pain-associated cues prove to have a relevant pain augmenting effect, in some subgroups, procedures aimed at extinguishing pain-related associations may have therapeutic potential.

Image processing for identification and quantification of filamentous bacteria in in situ acquired images.

PubMed

Dias, Philipe A; Dunkel, Thiemo; Fajado, Diego A S; Gallegos, Erika de León; Denecke, Martin; Wiedemann, Philipp; Schneider, Fabio K; Suhr, Hajo

2016-06-11

In the activated sludge process, problems of filamentous bulking and foaming can occur due to overgrowth of certain filamentous bacteria. Nowadays, these microorganisms are typically monitored by means of light microscopy, commonly combined with staining techniques. As drawbacks, these methods are susceptible to human errors, subjectivity and limited by the use of discontinuous microscopy. The in situ microscope appears as a suitable tool for continuous monitoring of filamentous bacteria, providing real-time examination, automated analysis and eliminating sampling, preparation and transport of samples. In this context, a proper image processing algorithm is proposed for automated recognition and measurement of filamentous objects. This work introduces a method for real-time evaluation of images without any staining, phase-contrast or dilution techniques, differently from studies present in the literature. Moreover, we introduce an algorithm which estimates the total extended filament length based on geodesic distance calculation. For a period of twelve months, samples from an industrial activated sludge plant were weekly collected and imaged without any prior conditioning, replicating real environment conditions. Trends of filament growth rate-the most important parameter for decision making-are correctly identified. For reference images whose filaments were marked by specialists, the algorithm correctly recognized 72 % of the filaments pixels, with a false positive rate of at most 14 %. An average execution time of 0.7 s per image was achieved. Experiments have shown that the designed algorithm provided a suitable quantification of filaments when compared with human perception and standard methods. The algorithm's average execution time proved its suitability for being optimally mapped into a computational architecture to provide real-time monitoring.

Improving statistical inference on pathogen densities estimated by quantitative molecular methods: malaria gametocytaemia as a case study.

PubMed

Walker, Martin; Basáñez, María-Gloria; Ouédraogo, André Lin; Hermsen, Cornelus; Bousema, Teun; Churcher, Thomas S

2015-01-16

Quantitative molecular methods (QMMs) such as quantitative real-time polymerase chain reaction (q-PCR), reverse-transcriptase PCR (qRT-PCR) and quantitative nucleic acid sequence-based amplification (QT-NASBA) are increasingly used to estimate pathogen density in a variety of clinical and epidemiological contexts. These methods are often classified as semi-quantitative, yet estimates of reliability or sensitivity are seldom reported. Here, a statistical framework is developed for assessing the reliability (uncertainty) of pathogen densities estimated using QMMs and the associated diagnostic sensitivity. The method is illustrated with quantification of Plasmodium falciparum gametocytaemia by QT-NASBA. The reliability of pathogen (e.g. gametocyte) densities, and the accompanying diagnostic sensitivity, estimated by two contrasting statistical calibration techniques, are compared; a traditional method and a mixed model Bayesian approach. The latter accounts for statistical dependence of QMM assays run under identical laboratory protocols and permits structural modelling of experimental measurements, allowing precision to vary with pathogen density. Traditional calibration cannot account for inter-assay variability arising from imperfect QMMs and generates estimates of pathogen density that have poor reliability, are variable among assays and inaccurately reflect diagnostic sensitivity. The Bayesian mixed model approach assimilates information from replica QMM assays, improving reliability and inter-assay homogeneity, providing an accurate appraisal of quantitative and diagnostic performance. Bayesian mixed model statistical calibration supersedes traditional techniques in the context of QMM-derived estimates of pathogen density, offering the potential to improve substantially the depth and quality of clinical and epidemiological inference for a wide variety of pathogens.

Impact of Sensory Sensitivity on Physiological Stress Response and Novel Peer Interaction in Children with and without Autism Spectrum Disorder.

PubMed

Corbett, Blythe A; Muscatello, Rachael A; Blain, Scott D

2016-01-01

For many children with Autism Spectrum Disorder (ASD), social interactions can be stressful. Previous research shows that youth with ASD exhibit greater physiological stress response during peer interaction, compared to typically developing (TD) peers. Heightened sensory sensitivity may contribute to maladaptive patterns of stress and anxiety. The current study investigated between-group differences in stress response to peer interaction, as well as the role of sensory sensitivity. Participants included 80 children (40 ASD) between 8 and 12 years. Children participated in the peer interaction paradigm (PIP), an ecologically valid protocol that simulates real-world social interaction. Salivary cortisol was collected before and after the 20 min PIP. Parents completed questionnaires pertaining to child stress (Stress Survey Schedule) and sensory sensitivity (Short Sensory Profile). Statistical analyses included t-tests and ANCOVA models to examine between-group differences in cortisol and play; Pearson correlations to determine relations between cortisol, play, and questionnaire scores; and moderation analyses to investigate interactions among variables. Controlling for baseline cortisol values, children with ASD showed significantly higher cortisol levels than TD peers, in response to the PIP [F (1, 77) = 5.77, p = 0.02]. Cortisol during play was negatively correlated with scores on the SSP (r = -0.242, p = 0.03), and positively correlated with SSS (r = 0.273, p = 0.02) indicating that higher cortisol was associated with greater sensory sensitivity (lower SSP reflects more impairment) and enhanced stress in various contexts (higher SSS reflects more stress). Furthermore, diagnosis was a significant moderator of the relation between cortisol and SSP, at multiple time points during the PIP (p < 0.05). The current study extends previous findings by showing that higher physiological arousal during play is associated with heightened sensory sensitivity and a pattern of increased stress in various contexts. RESULTS are discussed in a broader context, emphasizing the need to examine relationships between social, behavioral, and physiological profiles in ASD to enhance understanding and improve treatments aimed at ameliorating stress and sensory dysfunction, while enhancing social skills.

Rapid interactions between lexical semantic and word form analysis during word recognition in context: evidence from ERPs.

PubMed

Kim, Albert; Lai, Vicky

2012-05-01

We used ERPs to investigate the time course of interactions between lexical semantic and sublexical visual word form processing during word recognition. Participants read sentence-embedded pseudowords that orthographically resembled a contextually supported real word (e.g., "She measured the flour so she could bake a ceke…") or did not (e.g., "She measured the flour so she could bake a tont…") along with nonword consonant strings (e.g., "She measured the flour so she could bake a srdt…"). Pseudowords that resembled a contextually supported real word ("ceke") elicited an enhanced positivity at 130 msec (P130), relative to real words (e.g., "She measured the flour so she could bake a cake…"). Pseudowords that did not resemble a plausible real word ("tont") enhanced the N170 component, as did nonword consonant strings ("srdt"). The effect pattern shows that the visual word recognition system is, perhaps, counterintuitively, more rapidly sensitive to minor than to flagrant deviations from contextually predicted inputs. The findings are consistent with rapid interactions between lexical and sublexical representations during word recognition, in which rapid lexical access of a contextually supported word (CAKE) provides top-down excitation of form features ("cake"), highlighting the anomaly of an unexpected word "ceke."

A system and method for online high-resolution mapping of gastric slow-wave activity.

PubMed

Bull, Simon H; O'Grady, Gregory; Du, Peng; Cheng, Leo K

2014-11-01

High-resolution (HR) mapping employs multielectrode arrays to achieve spatially detailed analyses of propagating bioelectrical events. A major current limitation is that spatial analyses must currently be performed "off-line" (after experiments), compromising timely recording feedback and restricting experimental interventions. These problems motivated development of a system and method for "online" HR mapping. HR gastric recordings were acquired and streamed to a novel software client. Algorithms were devised to filter data, identify slow-wave events, eliminate corrupt channels, and cluster activation events. A graphical user interface animated data and plotted electrograms and maps. Results were compared against off-line methods. The online system analyzed 256-channel serosal recordings with no unexpected system terminations with a mean delay 18 s. Activation time marking sensitivity was 0.92; positive predictive value was 0.93. Abnormal slow-wave patterns including conduction blocks, ectopic pacemaking, and colliding wave fronts were reliably identified. Compared to traditional analysis methods, online mapping had comparable results with equivalent coverage of 90% of electrodes, average RMS errors of less than 1 s, and CC of activation maps of 0.99. Accurate slow-wave mapping was achieved in near real-time, enabling monitoring of recording quality and experimental interventions targeted to dysrhythmic onset. This work also advances the translation of HR mapping toward real-time clinical application.

Coherent ultra dense wavelength division multiplexing passive optical networks

NASA Astrophysics Data System (ADS)

Shahpari, Ali; Ferreira, Ricardo; Ribeiro, Vitor; Sousa, Artur; Ziaie, Somayeh; Tavares, Ana; Vujicic, Zoran; Guiomar, Fernando P.; Reis, Jacklyn D.; Pinto, Armando N.; Teixeira, António

2015-12-01

In this paper, we firstly review the progress in ultra-dense wavelength division multiplexing passive optical network (UDWDM-PON), by making use of the key attributes of this technology in the context of optical access and metro networks. Besides the inherit properties of coherent technology, we explore different modulation formats and pulse shaping. The performance is experimentally demonstrated through a 12 × 10 Gb/s bidirectional UDWDM-PON over hybrid 80 km standard single mode fiber (SSMF) and optical wireless link. High density, 6.25 GHz grid, Nyquist shaped 16-ary quadrature amplitude modulation (16QAM) and digital frequency shifting are some of the properties exploited together in the tests. Also, bidirectional transmission in fiber, relevant in the context, is analyzed in terms of nonlinear and back-reflection effects on receiver sensitivity. In addition, as a basis for the discussion on market readiness, we experimentally demonstrate real-time detection of a Nyquist-shaped quaternary phase-shift keying (QPSK) signal using simple 8-bit digital signal processing (DSP) on a field-programmable gate array (FPGA).

Comparison of Microscopy, Nested-PCR, and Real-Time-PCR Assays Using High-Throughput Screening of Pooled Samples for Diagnosis of Malaria in Asymptomatic Carriers from Areas of Endemicity in Myanmar

PubMed Central

Wang, Bo; Han, Soe-Soe; Cho, Cho; Han, Jin-Hee; Cheng, Yang; Lee, Seong-Kyun; Galappaththy, Gawrie N. L; Thimasarn, Krongthong; Soe, Myat Thu; Oo, Htet Wai; Kyaw, Myat Phone

2014-01-01

Asymptomatic infection is an important obstacle for controlling disease in countries where malaria is endemic. Because asymptomatic carriers do not seek treatment for their infections, they can have high levels of gametocytes and constitute a reservoir available for new infection. We employed a sample pooling/PCR-based molecular detection strategy for screening malaria infection in residents from areas of Myanmar where malaria is endemic. Blood samples (n = 1,552) were collected from residents in three areas of malaria endemicity (Kayin State, Bago, and Tanintharyi regions) of Myanmar. Two nested PCR and real-time PCR assays showed that asymptomatic infection was detected in about 1.0% to 9.4% of residents from the surveyed areas. The sensitivities of the two nested PCR and real-time PCR techniques were higher than that of microscopy examination (sensitivity, 100% versus 26.4%; kappa values, 0.2 to 0.5). Among the three regions, parasite-positive samples were highly detected in subjects from the Bago and Tanintharyi regions. Active surveillance of residents from regions of intense malaria transmission would reduce the risk of morbidity and mitigate transmission to the population in these areas of endemicity. Our data demonstrate that PCR-based molecular techniques are more efficient than microscopy for nationwide surveillance of malaria in countries where malaria is endemic. PMID:24648557

Tear thinning time and topical anesthesia as assessed using the HIRCAL grid and the NCCA.

PubMed

Blades, K J; Murphy, P J; Patel, S

1999-03-01

The literature contains conflicting reports of the effects of topical anesthetics on tear film stability, with some consensus that unpreserved topical anesthetics are less likely to reduce tear film stability than preserved preparations. This experiment investigated the effect of unpreserved 0.4% benoxinate hydrochloride on tear thinning time (TTT), in parallel with "real time" corneal sensitivity assessment. Tear film stability was assessed (HIRCAL grid) in parallel with real time assessment of the pharmacological activity (NCCA) of unpreserved 0.4% benoxinate hydrochloride in normal eyes. The anesthetic used did not significantly affect tear film stability. This finding is in agreement with previous investigators. Unpreserved 0.4% benoxinate hydrochloride could be used to facilitate tear film stability assessment. The experimental protocol used could also be applied to investigate the temporal relationship between anesthesia and tear film stability with preserved topical anesthetics that have been found to decrease tear film stability.

Evaluation of a new automated Abbott RealTime MTB RIF/INH assay for qualitative detection of rifampicin/isoniazid resistance in pulmonary and extra-pulmonary clinical samples of Mycobacterium tuberculosis.

PubMed

Ruiz, Pilar; Causse, Manuel; Vaquero, Manuel; Gutierrez, Juan Bautista; Casal, Manuel

2017-01-01

A new automated real-time PCR assay for the detection of rifampicin (RIF) and isoniazid (INH) resistance in Mycobacterium tuberculosis (MTB) was evaluated. A total of 163 clinical samples (128 pulmonary and 35 extra-pulmonary) were processed using four PCR assay kits: Abbott RealTime MTB RIF/INH, Genotype MTBDRplus, Xpert/MTB RIF, and Anyplex MTB/MDR. The results of phenotypic drug-susceptibility testing using BACTECMGIT 960 were used as reference. The sensitivity and specificity of the new Abbott RealTime MTB RIF/INH assay in comparison with phenotypic testing was 96.3% (95%CI 87.32%-100%) for RIF and 100% (95%CI 99.3%-100%) for INH; the sensitivity was 78.8% (95%CI 66.8%-90.9%) and the specificity was 100% (95%CI 98.9%-100%). The Abbott RealTime MTB RIF/INH test could be a valid method for detecting the most common mutations in strains resistant to RIF and INH.

A duplex real-time RT-PCR assay for detecting H5N1 avian influenza virus and pandemic H1N1 influenza virus.

PubMed

Kang, Xiao-ping; Jiang, Tao; Li, Yong-qiang; Lin, Fang; Liu, Hong; Chang, Guo-hui; Zhu, Qing-yu; Qin, E-de; Qin, Cheng-feng; Yang, Yin-hui

2010-06-02

A duplex real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay was improved for simultaneous detection of highly pathogenic H5N1 avian influenza virus and pandemic H1N1 (2009) influenza virus, which is suitable for early diagnosis of influenza-like patients and for epidemiological surveillance. The sensitivity of this duplex real-time RT-PCR assay was 0.02 TCID50 (50% tissue culture infective dose) for H5N1 and 0.2 TCID50 for the pandemic H1N1, which was the same as that of each single-target RT-PCR for pandemic H1N1 and even more sensitive for H5N1 with the same primers and probes. No cross reactivity of detecting other subtype influenza viruses or respiratory tract viruses was observed. Two hundred and thirty-six clinical specimens were tested by comparing with single real-time RT-PCR and result from the duplex assay was 100% consistent with the results of single real-time RT-PCR and sequence analysis.

Real-time fMRI neurofeedback to down-regulate superior temporal gyrus activity in patients with schizophrenia and auditory hallucinations: a proof-of-concept study.

PubMed

Orlov, Natasza D; Giampietro, Vincent; O'Daly, Owen; Lam, Sheut-Ling; Barker, Gareth J; Rubia, Katya; McGuire, Philip; Shergill, Sukhwinder S; Allen, Paul

2018-02-12

Neurocognitive models and previous neuroimaging work posit that auditory verbal hallucinations (AVH) arise due to increased activity in speech-sensitive regions of the left posterior superior temporal gyrus (STG). Here, we examined if patients with schizophrenia (SCZ) and AVH could be trained to down-regulate STG activity using real-time functional magnetic resonance imaging neurofeedback (rtfMRI-NF). We also examined the effects of rtfMRI-NF training on functional connectivity between the STG and other speech and language regions. Twelve patients with SCZ and treatment-refractory AVH were recruited to participate in the study and were trained to down-regulate STG activity using rtfMRI-NF, over four MRI scanner visits during a 2-week training period. STG activity and functional connectivity were compared pre- and post-training. Patients successfully learnt to down-regulate activity in their left STG over the rtfMRI-NF training. Post- training, patients showed increased functional connectivity between the left STG, the left inferior prefrontal gyrus (IFG) and the inferior parietal gyrus. The post-training increase in functional connectivity between the left STG and IFG was associated with a reduction in AVH symptoms over the training period. The speech-sensitive region of the left STG is a suitable target region for rtfMRI-NF in patients with SCZ and treatment-refractory AVH. Successful down-regulation of left STG activity can increase functional connectivity between speech motor and perception regions. These findings suggest that patients with AVH have the ability to alter activity and connectivity in speech and language regions, and raise the possibility that rtfMRI-NF training could present a novel therapeutic intervention in SCZ.

In- and ex-vivo molecular imaging of apoptosis to assess sensitivity of non-small cell lung cancer to EGFR inhibitors using probe-based confocal laser endomicroscopy.

PubMed

Guisier, Florian; Bohn, Pierre; Patout, Maxime; Piton, Nicolas; Farah, Insaf; Vera, Pierre; Thiberville, Luc; Salaün, Mathieu

2017-01-01

Prediction of treatment outcome of non-small cell lung cancer (NSCLC) with EGFR inhibitors on the basis of the genetic analysis of the tumor can be incorrect in case of rare or complex mutations, bypass molecular activation pathways, or pharmacodynamic variations. The aim of this study was to develop an ex vivo and in vivo real-time quantitative imaging test for EGFR inhibitors sensitivity assessment. Erlotinib resistant (A549, H460, H1975), insensitive (H1650) and hypersensitive (HCC827) cell lines were injected subcutaneously in Nude mice. Tumor xenografts from mice treated with Erlotinib were imaged ex vivo and in vivo using probe-based confocal laser endomicroscopy (pCLE) and NucView 488 Caspase 3 substrate, a fluorescent probe specific for the activated caspase 3. Assessment of apoptosis at 24h post treatment, both ex vivo in explanted tumor xenografts and in vivo, showed a significant difference between resistant cell lines (A549, H460 and H1975) and insensitive (H1650) or hypersensitive (HCC827) ones (p<0.05 for ex vivo imaging, p≤0.02 for in vivo imaging). There was also a significant difference between insensitive and hypersensitive cell lines, both ex vivo (p<0.05) and in vivo (p = 0.01). Real-time in vivo and ex vivo assessment of apoptosis using pCLE differentiates resistant from sensitive NSCLC xenografts to Erlotinib.

Assessment of real-time PCR method for detection of EGFR mutation using both supernatant and cell pellet of malignant pleural effusion samples from non-small-cell lung cancer patients.

PubMed

Shin, Saeam; Kim, Juwon; Kim, Yoonjung; Cho, Sun-Mi; Lee, Kyung-A

2017-10-26

EGFR mutation is an emerging biomarker for treatment selection in non-small-cell lung cancer (NSCLC) patients. However, optimal mutation detection is hindered by complications associated with the biopsy procedure, tumor heterogeneity and limited sensitivity of test methodology. In this study, we evaluated the diagnostic utility of real-time PCR using malignant pleural effusion samples. A total of 77 pleural fluid samples from 77 NSCLC patients were tested using the cobas EGFR mutation test (Roche Molecular Systems). Pleural fluid was centrifuged, and separated cell pellets and supernatants were tested in parallel. Results were compared with Sanger sequencing and/or peptide nucleic acid (PNA)-mediated PCR clamping of matched tumor tissue or pleural fluid samples. All samples showed valid real-time PCR results in one or more DNA samples extracted from cell pellets and supernatants. Compared with other molecular methods, the sensitivity of real-time PCR method was 100%. Concordance rate of real-time PCR and Sanger sequencing plus PNA-mediated PCR clamping was 98.7%. We have confirmed that real-time PCR using pleural fluid had a high concordance rate compared to conventional methods, with no failed samples. Our data demonstrated that the parallel real-time PCR testing using supernatant and cell pellet could offer reliable and robust surrogate strategy when tissue is not available.

The 3D Recognition, Generation, Fusion, Update and Refinement (RG4) Concept

NASA Technical Reports Server (NTRS)

Maluf, David A.; Cheeseman, Peter; Smelyanskyi, Vadim N.; Kuehnel, Frank; Morris, Robin D.; Norvig, Peter (Technical Monitor)

2001-01-01

This paper describes an active (real time) recognition strategy whereby information is inferred iteratively across several viewpoints in descent imagery. We will show how we use inverse theory within the context of parametric model generation, namely height and spectral reflection functions, to generate model assertions. Using this strategy in an active context implies that, from every viewpoint, the proposed system must refine its hypotheses taking into account the image and the effect of uncertainties as well. The proposed system employs probabilistic solutions to the problem of iteratively merging information (images) from several viewpoints. This involves feeding the posterior distribution from all previous images as a prior for the next view. Novel approaches will be developed to accelerate the inversion search using novel statistic implementations and reducing the model complexity using foveated vision. Foveated vision refers to imagery where the resolution varies across the image. In this paper, we allow the model to be foveated where the highest resolution region is called the foveation region. Typically, the images will have dynamic control of the location of the foveation region. For descent imagery in the Entry, Descent, and Landing (EDL) process, it is possible to have more than one foveation region. This research initiative is directed towards descent imagery in connection with NASA's EDL applications. Three-Dimensional Model Recognition, Generation, Fusion, Update, and Refinement (RGFUR or RG4) for height and the spectral reflection characteristics are in focus for various reasons, one of which is the prospect that their interpretation will provide for real time active vision for automated EDL.

Real-time scalable visual analysis on mobile devices

NASA Astrophysics Data System (ADS)

Pattath, Avin; Ebert, David S.; May, Richard A.; Collins, Timothy F.; Pike, William

2008-02-01

Interactive visual presentation of information can help an analyst gain faster and better insight from data. When combined with situational or context information, visualization on mobile devices is invaluable to in-field responders and investigators. However, several challenges are posed by the form-factor of mobile devices in developing such systems. In this paper, we classify these challenges into two broad categories - issues in general mobile computing and issues specific to visual analysis on mobile devices. Using NetworkVis and Infostar as example systems, we illustrate some of the techniques that we employed to overcome many of the identified challenges. NetworkVis is an OpenVG-based real-time network monitoring and visualization system developed for Windows Mobile devices. Infostar is a flash-based interactive, real-time visualization application intended to provide attendees access to conference information. Linked time-synchronous visualization, stylus/button-based interactivity, vector graphics, overview-context techniques, details-on-demand and statistical information display are some of the highlights of these applications.

Real-time assessment of inflammation and treatment response in a mouse model of allergic airway inflammation

PubMed Central

Cortez-Retamozo, Virna; Swirski, Filip K.; Waterman, Peter; Yuan, Hushan; Figueiredo, Jose Luiz; Newton, Andita P.; Upadhyay, Rabi; Vinegoni, Claudio; Kohler, Rainer; Blois, Joseph; Smith, Adam; Nahrendorf, Matthias; Josephson, Lee; Weissleder, Ralph; Pittet, Mikael J.

2008-01-01

Eosinophils are multifunctional leukocytes that degrade and remodel tissue extracellular matrix through production of proteolytic enzymes, release of proinflammatory factors to initiate and propagate inflammatory responses, and direct activation of mucus secretion and smooth muscle cell constriction. Thus, eosinophils are central effector cells during allergic airway inflammation and an important clinical therapeutic target. Here we describe the use of an injectable MMP-targeted optical sensor that specifically and quantitatively resolves eosinophil activity in the lungs of mice with experimental allergic airway inflammation. Through the use of real-time molecular imaging methods, we report the visualization of eosinophil responses in vivo and at different scales. Eosinophil responses were seen at single-cell resolution in conducting airways using near-infrared fluorescence fiberoptic bronchoscopy, in lung parenchyma using intravital microscopy, and in the whole body using fluorescence-mediated molecular tomography. Using these real-time imaging methods, we confirmed the immunosuppressive effects of the glucocorticoid drug dexamethasone in the mouse model of allergic airway inflammation and identified a viridin-derived prodrug that potently inhibited the accumulation and enzyme activity of eosinophils in the lungs. The combination of sensitive enzyme-targeted sensors with noninvasive molecular imaging approaches permitted evaluation of airway inflammation severity and was used as a model to rapidly screen for new drug effects. Both fluorescence-mediated tomography and fiberoptic bronchoscopy techniques have the potential to be translated into the clinic. PMID:19033674

PSMA-mediated endosome escape-accelerating polymeric micelles for targeted therapy of prostate cancer and the real time tracing of their intracellular trafficking

NASA Astrophysics Data System (ADS)

Gao, Yajie; Li, Yanfang; Li, Yushu; Yuan, Lan; Zhou, Yanxia; Li, Jinwen; Zhao, Lei; Zhang, Chao; Li, Xinru; Liu, Yan

2014-12-01

The cytotoxicity of chemotherapeutic agents to healthy organs and drug resistance of tumor cells are believed to be the main obstacles to the successful cancer chemotherapy in the clinic. To ensure that anticancer drugs could be delivered to the tumor region, are quickly released from carriers in tumor cells and rapidly escape from endo/lysosomes, YPSMA-1-modified pH-sensitive polymeric micelles, which would be advantageous in recognizing the prostate specific membrane antigen (PSMA), were designed and fabricated for targeted delivery of paclitaxel to tumors based on the pH-sensitive diblock copolymer poly(2-ethyl-2-oxazoline)-poly(d,l-lactide) (PEOz-PLA) and YPSMA-1-PEOz-PLA for treating prostate cancer. HOOC-PEOz-PLA with a critical micelle concentration of 5.0 mg L-1 was synthesized and characterized by 1H NMR and gel permeation chromatography. The prepared YPSMA-1-modified micelles, about 30 nm in diameter, exhibited a rapid release behavior at endo/lysosome pH and a favorable ability of fast endo/lysosome escape as observed by confocal microscopy. More importantly, we evidenced for the first time that both endosome and lysosome escape existed for pH-sensitive micelles via real time tracing using confocal microscopy, and the real time endo/lysosome escape process was also presented. The YPSMA-1-modified micelles were very effective in enhancing the cytotoxicity of paclitaxel by increasing the cellular uptake in PSMA-positive 22Rv1 cells, which was verified the correlation with PSMA expression in tumor cells by flow cytometric analysis and confocal microscopy. Moreover, the active targeting and pH-sensitivity endowed YPSMA-1-modified micelles with a higher antitumor efficacy and negligible systemic toxicity in 22Rv1 xenograft-bearing nude mice compared with unmodified micelles and Taxol®. These results suggested that the application of combining YPSMA-1 modification with pH-sensitivity to polymeric micelles may be one approach in the efficient delivery of anticancer drugs for treating PSMA-positive prostate cancers.

Generalized event knowledge activation during online sentence comprehension

PubMed Central

Metusalem, Ross; Kutas, Marta; Urbach, Thomas P.; Hare, Mary; McRae, Ken; Elman, Jeffrey L.

2012-01-01

Recent research has demonstrated that knowledge of real-world eventsplays an important role inguiding online language comprehension. The present study addresses the scope of event knowledge activation during the course of comprehension, specifically investigating whether activation is limited to those knowledge elements that align with the local linguistic context.The present study addresses this issue by analyzing event-related brain potentials (ERPs) recorded as participants read brief scenariosdescribing typical real-world events. Experiment 1 demonstratesthat a contextually anomalous word elicits a reduced N400 if it is generally related to the described event, even when controlling for the degree of association of this word with individual words in the preceding context and with the expected continuation. Experiment 2 shows that this effect disappears when the discourse context is removed.These findings demonstrate that during the course of incremental comprehension, comprehenders activate general knowledge about the described event, even at points at which this knowledge would constitute an anomalous continuation of the linguistic stream. Generalized event knowledge activationcontributes to mental representations of described events, is immediately available to influence language processing, and likely drives linguistic expectancy generation. PMID:22711976

Towards real-time medical diagnostics using hyperspectral imaging technology

NASA Astrophysics Data System (ADS)

Bjorgan, Asgeir; Randeberg, Lise L.

2015-07-01

Hyperspectral imaging provides non-contact, high resolution spectral images which has a substantial diagnostic potential. This can be used for e.g. diagnosis and early detection of arthritis in finger joints. Processing speed is currently a limitation for clinical use of the technique. A real-time system for analysis and visualization using GPU processing and threaded CPU processing is presented. Images showing blood oxygenation, blood volume fraction and vessel enhanced images are among the data calculated in real-time. This study shows the potential of real-time processing in this context. A combination of the processing modules will be used in detection of arthritic finger joints from hyperspectral reflectance and transmittance data.

Evaluation of NK Cell Function by Flowcytometric Measurement and Impedance Based Assay Using Real-Time Cell Electronic Sensing System

PubMed Central

Park, Ki-Hyun; Park, Hyesun; Kim, Myungshin; Kim, Yonggoo; Han, Kyungja; Oh, Eun-Jee

2013-01-01

Although real-time cell electronic sensing (RT-CES) system-based natural killer (NK) cytotoxicity has been introduced, it has not been evaluated using human blood samples. In present study, we measured flowcytometry based assay (FCA) and RT-CES based NK cytotoxicity and analyzed degranulation activity (CD107a) and cytokine production. In 98 healthy individuals, FCA with peripheral blood mononuclear cells (PBMCs) at effector to target (E/T) ratio of 32 revealed 46.5 ± 2.6% cytolysis of K562 cells, and 23.5 ± 1.1% of NK cells showed increased degranulation. In RT-CES system, adherent NIH3T3 target cells were resistant to basal killing by PBMC or NK cells. NK cell activation by adding IL-2 demonstrated real-time dynamic killing activity, and lymphokine-activated PBMC (E/T ratio of 32) from 15 individuals showed 59.1 ± 6.2% cytotoxicity results after 4 hours incubation in RT-CES system. However, there was no significant correlation between FCA and RT-CES cytotoxicity. After K562 target cell stimulation, PBMC produced profound proinflammatory and immunoregulatory cytokines/chemokines including IL-2, IL-8, IL-10, MIP-1α β, IFN-γ, and TNF-α, and cytokine/chemokine secretion was related to flowcytometry-based NK cytotoxicity. These data suggest that RT-CES and FCA differ in sensitivity, applicability and providing information, and further investigations are necessary in variable clinical conditions. PMID:24236291

Evaluation of NK cell function by flowcytometric measurement and impedance based assay using real-time cell electronic sensing system.

PubMed

Park, Ki-Hyun; Park, Hyesun; Kim, Myungshin; Kim, Yonggoo; Han, Kyungja; Oh, Eun-Jee

2013-01-01

Although real-time cell electronic sensing (RT-CES) system-based natural killer (NK) cytotoxicity has been introduced, it has not been evaluated using human blood samples. In present study, we measured flowcytometry based assay (FCA) and RT-CES based NK cytotoxicity and analyzed degranulation activity (CD107a) and cytokine production. In 98 healthy individuals, FCA with peripheral blood mononuclear cells (PBMCs) at effector to target (E/T) ratio of 32 revealed 46.5 ± 2.6% cytolysis of K562 cells, and 23.5 ± 1.1% of NK cells showed increased degranulation. In RT-CES system, adherent NIH3T3 target cells were resistant to basal killing by PBMC or NK cells. NK cell activation by adding IL-2 demonstrated real-time dynamic killing activity, and lymphokine-activated PBMC (E/T ratio of 32) from 15 individuals showed 59.1 ± 6.2% cytotoxicity results after 4 hours incubation in RT-CES system. However, there was no significant correlation between FCA and RT-CES cytotoxicity. After K562 target cell stimulation, PBMC produced profound proinflammatory and immunoregulatory cytokines/chemokines including IL-2, IL-8, IL-10, MIP-1 α β , IFN- γ , and TNF- α , and cytokine/chemokine secretion was related to flowcytometry-based NK cytotoxicity. These data suggest that RT-CES and FCA differ in sensitivity, applicability and providing information, and further investigations are necessary in variable clinical conditions.

Small-volume cavity cell using hollow optical fiber for Raman scattering-based gas detection

NASA Astrophysics Data System (ADS)

Okita, Y.; Katagiri, T.; Matsuura, Y.

2011-03-01

The highly sensitive Raman cell based on the hollow optical fiber that is suitable for the real-time breath analysis is reported. Hollow optical fiber with inner coating of silver is used as a gas cell and a Stokes light collector. A very small cell whose volume is only 0.4 ml or less enables fast response and real-time measurement of trace gases. To increase the sensitivity the cell is arranged in a cavity which includes of a long-pass filter and a high reflective mirror. The sensitivity of the cavity cell is more than two times higher than that of the cell without cavity.

Longevity of rAAV vector and plasmid DNA in blood after intramuscular injection in nonhuman primates: implications for gene doping.

PubMed

Ni, W; Le Guiner, C; Gernoux, G; Penaud-Budloo, M; Moullier, P; Snyder, R O

2011-07-01

Legitimate uses of gene transfer technology can benefit from sensitive detection methods to determine vector biodistribution in pre-clinical studies and in human clinical trials, and similar methods can detect illegitimate gene transfer to provide sports-governing bodies with the ability to maintain fairness. Real-time PCR assays were developed to detect a performance-enhancing transgene (erythropoietin, EPO) and backbone sequences in the presence of endogenous cellular sequences. In addition to developing real-time PCR assays, the steps involved in DNA extraction, storage and transport were investigated. By real-time PCR, the vector transgene is distinguishable from the genomic DNA sequence because of the absence of introns, and the vector backbone can be identified by heterologous gene expression control elements. After performance of the assays was optimized, cynomolgus macaques received a single dose by intramuscular (IM) injection of plasmid DNA, a recombinant adeno-associated viral vector serotype 1 (rAAV1) or a rAAV8 vector expressing cynomolgus macaque EPO. Macaques received a high plasmid dose intended to achieve a significant, but not life-threatening, increase in hematocrit. rAAV vectors were used at low doses to achieve a small increase in hematocrit and to determine the limit of sensitivity for detecting rAAV sequences by single-step PCR. DNA extracted from white blood cells (WBCs) was tested to determine whether WBCs can be collaterally transfected by plasmid or transduced by rAAV vectors in this context, and can be used as a surrogate marker for gene doping. We demonstrate that IM injection of a conventional plasmid and rAAV vectors results in the presence of DNA that can be detected at high levels in blood before rapid elimination, and that rAAV genomes can persist for several months in WBCs.

On the facilitative effects of face motion on face recognition and its development

PubMed Central

Xiao, Naiqi G.; Perrotta, Steve; Quinn, Paul C.; Wang, Zhe; Sun, Yu-Hao P.; Lee, Kang

2014-01-01

For the past century, researchers have extensively studied human face processing and its development. These studies have advanced our understanding of not only face processing, but also visual processing in general. However, most of what we know about face processing was investigated using static face images as stimuli. Therefore, an important question arises: to what extent does our understanding of static face processing generalize to face processing in real-life contexts in which faces are mostly moving? The present article addresses this question by examining recent studies on moving face processing to uncover the influence of facial movements on face processing and its development. First, we describe evidence on the facilitative effects of facial movements on face recognition and two related theoretical hypotheses: the supplementary information hypothesis and the representation enhancement hypothesis. We then highlight several recent studies suggesting that facial movements optimize face processing by activating specific face processing strategies that accommodate to task requirements. Lastly, we review the influence of facial movements on the development of face processing in the first year of life. We focus on infants' sensitivity to facial movements and explore the facilitative effects of facial movements on infants' face recognition performance. We conclude by outlining several future directions to investigate moving face processing and emphasize the importance of including dynamic aspects of facial information to further understand face processing in real-life contexts. PMID:25009517

Clinical evaluation of the Abbott RealTime MTB Assay for direct detection of Mycobacterium tuberculosis-complex from respiratory and non-respiratory samples.

PubMed

Hinić, Vladimira; Feuz, Kinga; Turan, Selda; Berini, Andrea; Frei, Reno; Pfeifer, Karin; Goldenberger, Daniel

2017-05-01

Rapid and reliable diagnosis is crucial for correct management of tuberculosis. The Abbott RealTime MTB Assay represents a novel qualitative real-time PCR assay for direct detection of M. tuberculosis-complex (MTB) DNA from respiratory samples. The test targets two highly conserved sequences, the multi-copy insertion element IS6110 and the protein antigen B (PAB) gene of MTB, allowing even the detection of IS6610-deficient strains. We evaluated this commercial diagnostic test by analyzing 200 respiratory and, for the first time, 87 non-respiratory clinical specimens from our tertiary care institution and compared its results to our IS6110-based in-house real-time PCR for MTB as well as MTB culture. Overall sensitivity for Abbott RealTime MTB was 100% (19/19) in smear positive and 87.5% (7/8) in smear negative specimens, while the specificity of the assay was 100% (260/260). For both non-respiratory smear positive and smear negative specimens Abbott RealTime MTB tests showed 100% (8/8) sensitivity and 100% (8/8) specificity. Cycle threshold (Ct) value analysis of 16 MTB positive samples showed a slightly higher Ct value of the Abbott RealTime MTB test compared to our in-house MTB assay (mean delta Ct = 2.55). In conclusion, the performance of the new Abbott RealTime MTB Assay was highly similar to culture and in-house MTB PCR. We document successful analysis of 87 non-respiratory samples with the highly automated Abbott RealTime MTB test with no inhibition observed. Copyright © 2017 Elsevier Ltd. All rights reserved.

An active co-phasing imaging testbed with segmented mirrors

NASA Astrophysics Data System (ADS)

Zhao, Weirui; Cao, Genrui

2011-06-01

An active co-phasing imaging testbed with high accurate optical adjustment and control in nanometer scale was set up to validate the algorithms of piston and tip-tilt error sensing and real-time adjusting. Modularization design was adopted. The primary mirror was spherical and divided into three sub-mirrors. One of them was fixed and worked as reference segment, the others were adjustable respectively related to the fixed segment in three freedoms (piston, tip and tilt) by using sensitive micro-displacement actuators in the range of 15mm with a resolution of 3nm. The method of twodimension dispersed fringe analysis was used to sense the piston error between the adjacent segments in the range of 200μm with a repeatability of 2nm. And the tip-tilt error was gained with the method of centroid sensing. Co-phasing image could be realized by correcting the errors measured above with the sensitive micro-displacement actuators driven by a computer. The process of co-phasing error sensing and correcting could be monitored in real time by a scrutiny module set in this testbed. A FISBA interferometer was introduced to evaluate the co-phasing performance, and finally a total residual surface error of about 50nm rms was achieved.

Real-time reverse transcription polymerase chain reaction method for detection of Canine distemper virus modified live vaccine shedding for differentiation from infection with wild-type strains.

PubMed

Wilkes, Rebecca P; Sanchez, Elena; Riley, Matthew C; Kennedy, Melissa A

2014-01-01

Canine distemper virus (CDV) remains a common cause of infectious disease in dogs, particularly in high-density housing situations such as shelters. Vaccination of all dogs against CDV is recommended at the time of admission to animal shelters and many use a modified live virus (MLV) vaccine. From a diagnostic standpoint for dogs with suspected CDV infection, this is problematic because highly sensitive diagnostic real-time reverse transcription polymerase chain reaction (RT-PCR) tests are able to detect MLV virus in clinical samples. Real-time PCR can be used to quantitate amount of virus shedding and can differentiate vaccine strains from wild-type strains when shedding is high. However, differentiation by quantitation is not possible in vaccinated animals during acute infection, when shedding is low and could be mistaken for low level vaccine virus shedding. While there are gel-based RT-PCR assays for differentiation of vaccine strains from field strains based on sequence differences, the sensitivity of these assays is unable to match that of the real-time RT-PCR assay currently used in the authors' laboratory. Therefore, a real-time RT-PCR assay was developed that detects CDV MLV vaccine strains and distinguishes them from wild-type strains based on nucleotide sequence differences, rather than the amount of viral RNA in the sample. The test is highly sensitive, with detection of as few as 5 virus genomic copies (corresponding to 10(-1) TCID(50)). Sequencing of the DNA real-time products also allows phylogenetic differentiation of the wild-type strains. This test will aid diagnosis during outbreaks of CDV in recently vaccinated animals.

Detection of Onchocerca volvulus in Skin Snips by Microscopy and Real-Time Polymerase Chain Reaction: Implications for Monitoring and Evaluation Activities.

PubMed

Thiele, Elizabeth A; Cama, Vitaliano A; Lakwo, Thomson; Mekasha, Sindeaw; Abanyie, Francisca; Sleshi, Markos; Kebede, Amha; Cantey, Paul T

2016-04-01

Microscopic evaluation of skin biopsies is the monitoring and evaluation (M and E) method currently used by multiple onchocerciasis elimination programs in Africa. However, as repeated mass drug administration suppresses microfilarial loads, the sensitivity and programmatic utility of skin snip microscopy is expected to decrease. Using a pan-filarial real-time polymerase chain reaction with melt curve analysis (qPCR-MCA), we evaluated 1) the use of a single-step molecular assay for detecting and identifying Onchocerca volvulus microfilariae in residual skin snips and 2) the sensitivity of skin snip microscopy relative to qPCR-MCA. Skin snips were collected and examined with routine microscopy in hyperendemic regions of Uganda and Ethiopia (N= 500 each) and "residual" skin snips (tissue remaining after induced microfilarial emergence) were tested with qPCR-MCA. qPCR-MCA detected Onchocerca DNA in 223 residual snips: 139 of 147 microscopy(+) and 84 among microscopy(-) snips, suggesting overall sensitivity of microscopy was 62.3% (139/223) relative to qPCR-MCA (75.6% in Uganda and 28.6% in Ethiopia). These findings demonstrate the insufficient sensitivity of skin snip microscopy for reliable programmatic monitoring. Molecular tools such as qPCR-MCA can augment sensitivity and provide diagnostic confirmation of skin biopsies and will be useful for evaluation or validation of new onchocerciasis M and E tools. © The American Society of Tropical Medicine and Hygiene.

Innovative science within and against a culture of achievement

NASA Astrophysics Data System (ADS)

Carlone, Heidi B.

2003-05-01

As science educators struggle to reform science education, we need a better understanding of the conundrums associated with the ways educators enact innovative science within and against the academic, rigorous, and elite sociohistorical constructions of science. I ethnographically investigated the meanings of an innovative, reform-based curriculum (Active Physics) in various micro (classroom) and macro (school and community) contexts. I conducted the study in a high school serving primarily upper middle class students, the majority of whom (97%) planned to attend college. I explored how meanings of the curriculum transformed as the curriculum traveled across space and time. While certain aspects of the context enabled innovative science (e.g., support from the administration, pressure to serve a wider range of students), other aspects of the context constrained the potential of the curriculum (e.g., the need to establish for students, parents, and administrators the legitimacy of Active Physics as real and rigorous physics). Using practice theory to understand the influence of context and agency in shaping school science practice, this study demonstrates the potential for viewing meanings of science in local settings as partially fluid entities, sometimes reproducing and sometimes contesting sociohistorical legacies.

Cardiac Care Assistance using Self Configured Sensor Network—a Remote Patient Monitoring System

NASA Astrophysics Data System (ADS)

Sarma Dhulipala, V. R.; Kanagachidambaresan, G. R.

2014-04-01

Pervasive health care systems are used to monitor patients remotely without disturbing the normal day-to-day activities in real-time. Wearable physiological sensors required to monitor various significant ecological parameters of the patients are connected to Body Central Unit (BCU). Body Sensor Network (BSN) updates data in real-time and are designed to transmit alerts against abnormalities which enables quick response by medical units in case of an emergency. BSN helps monitoring patient without any need for attention to the subject. BSN helps in reducing the stress and strain caused by hospital environment. In this paper, mathematical models for heartbeat signal, electro cardio graph (ECG) signal and pulse rate are introduced. These signals are compared and their RMS difference-fast Fourier transforms (PRD-FFT) are processed. In the context of cardiac arrest, alert messages of these parameters and first aid for post-surgical operations has been suggested.

Integrating supply and demand aspects of transportation for mass evacuation under disasters.

DOT National Transportation Integrated Search

2009-10-15

This study seeks to address real-time operational needs in the context of the evacuation response problem by providing a capability to dynamically route vehicles under evacuation, thereby being responsive to the actual conditions unfolding in real-ti...

Development and validation of a real-time PCR assay for the detection of anguillid herpesvirus 1.

PubMed

van Beurden, S J; Voorbergen-Laarman, M A; Roozenburg, I; van Tellingen, J; Haenen, O L M; Engelsma, M Y

2016-01-01

Anguillid herpesvirus 1 (AngHV1) causes a haemorrhagic disease with increased mortality in wild and farmed European eel, Anguilla anguilla (L.) and Japanese eel Anguilla japonica, Temminck & Schlegel). Detection of AngHV1 is currently based on virus isolation in cell culture, antibody-based typing assays or conventional PCR. We developed, optimized and concisely validated a diagnostic TaqMan probe based real-time PCR assay for the detection of AngHV1. The primers and probe target AngHV1 open reading frame 57, encoding the capsid protease and scaffold protein. Compared to conventional PCR, the developed real-time PCR is faster, less labour-intensive and has a reduced risk of cross-contamination. The real-time PCR assay was shown to be analytically sensitive and specific and has a high repeatability, efficiency and r(2) -value. The diagnostic performance of the assay was determined by testing 10% w/v organ suspensions and virus cultures from wild and farmed European eels from the Netherlands by conventional and real-time PCR. The developed real-time PCR assay is a useful tool for the rapid and sensitive detection of AngHV1 in 10% w/v organ suspensions from wild and farmed European eels. © 2015 John Wiley & Sons Ltd.

Turkish- and English-speaking children display sensitivity to perceptual context in the referring expressions they produce in speech and gesture

PubMed Central

Demir, Özlem Ece; So, Wing-Chee; Özyürek, Asli; Goldin-Meadow, Susan

2012-01-01

Speakers choose a particular expression based on many factors, including availability of the referent in the perceptual context. We examined whether, when expressing referents, monolingual English- and Turkish-speaking children: (1) are sensitive to perceptual context, (2) express this sensitivity in language-specific ways, and (3) use co-speech gestures to specify referents that are underspecified. We also explored the mechanisms underlying children’s sensitivity to perceptual context. Children described short vignettes to an experimenter under two conditions: The characters in the vignettes were present in the perceptual context (perceptual context); the characters were absent (no perceptual context). Children routinely used nouns in the no perceptual context condition, but shifted to pronouns (English-speaking children) or omitted arguments (Turkish-speaking children) in the perceptual context condition. Turkish-speaking children used underspecified referents more frequently than English-speaking children in the perceptual context condition; however, they compensated for the difference by using gesture to specify the forms. Gesture thus gives children learning structurally different languages a way to achieve comparable levels of specification while at the same time adhering to the referential expressions dictated by their language. PMID:22904588

Using Drama to Support Literacy: Activities for Children Aged 7 to 14

ERIC Educational Resources Information Center

Goodwin, John

2006-01-01

The power of drama provides a real context for narrative writing, and in this book the tool kit of drama strategies has been laid out and used effectively by teachers across a wider range of imaginary contexts. Using drama makes possible a vast range of themes and story contexts which enthuse and hook children into the writing process. The real…

Multiplex Real-Time PCR Method for Simultaneous Identification and Toxigenic Type Characterization of Clostridium difficile From Stool Samples

PubMed Central

Alam, Mohammad J.; Tisdel, Naradah L.; Shah, Dhara N.; Yapar, Mehmet; Lasco, Todd M.; Garey, Kevin W.

2015-01-01

Background The aim of this study was to develop and validate a multiplex real-time PCR assay for simultaneous identification and toxigenic type characterization of Clostridium difficile. Methods The multiplex real-time PCR assay targeted and simultaneously detected triose phosphate isomerase (tpi) and binary toxin (cdtA) genes, and toxin A (tcdA) and B (tcdB) genes in the first and sec tubes, respectively. The results of multiplex real-time PCR were compared to those of the BD GeneOhm Cdiff assay, targeting the tcdB gene alone. The toxigenic culture was used as the reference, where toxin genes were detected by multiplex real-time PCR. Results A total of 351 stool samples from consecutive patients were included in the study. Fifty-five stool samples (15.6%) were determined to be positive for the presence of C. difficile by using multiplex real-time PCR. Of these, 48 (87.2%) were toxigenic (46 tcdA and tcdB-positive, two positive for only tcdB) and 11 (22.9%) were cdtA-positive. The sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of the multiplex real-time PCR compared with the toxigenic culture were 95.6%, 98.6%, 91.6%, and 99.3%, respectively. The analytical sensitivity of the multiplex real-time PCR assay was determined to be 103colonyforming unit (CFU)/g spiked stool sample and 0.0625 pg genomic DNA from culture. Analytical specificity determined by using 15 enteric and non-clostridial reference strains was 100%. Conclusions The multiplex real-time PCR assay accurately detected C. difficile isolates from diarrheal stool samples and characterized its toxin genes in a single PCR run. PMID:25932438

Modeling the N400 ERP component as transient semantic over-activation within a neural network model of word comprehension

PubMed Central

Cheyette, Samuel J.; Plaut, David C.

2016-01-01

The study of the N400 event-related brain potential has provided fundamental insights into the nature of real-time comprehension processes, and its amplitude is modulated by a wide variety of stimulus and context factors. It is generally thought to reflect the difficulty of semantic access, but formulating a precise characterization of this process has proved difficult. Laszlo and colleagues (Laszlo & Plaut, 2012, Brain and Language, 120, 271-281; Laszlo & Armstrong, 2014, Brain and Language, 132, 22-27) used physiologically constrained neural networks to model the N400 as transient over-activation within semantic representations, arising as a consequence of the distribution of excitation and inhibition within and between cortical areas. The current work extends this approach to successfully model effects on both N400 amplitudes and behavior of word frequency, semantic richness, repetition, semantic and associative priming, and orthographic neighborhood size. The account is argued to be preferable to one based on “implicit semantic prediction error” (Rabovsky & McRae, 2014, Cognition, 132, 68-98) for a number of reasons, the most fundamental of which is that the current model actually produces N400-like waveforms in its real-time activation dynamics. PMID:27871623

Modeling the N400 ERP component as transient semantic over-activation within a neural network model of word comprehension.

PubMed

Cheyette, Samuel J; Plaut, David C

2017-05-01

The study of the N400 event-related brain potential has provided fundamental insights into the nature of real-time comprehension processes, and its amplitude is modulated by a wide variety of stimulus and context factors. It is generally thought to reflect the difficulty of semantic access, but formulating a precise characterization of this process has proved difficult. Laszlo and colleagues (Laszlo & Plaut, 2012; Laszlo & Armstrong, 2014) used physiologically constrained neural networks to model the N400 as transient over-activation within semantic representations, arising as a consequence of the distribution of excitation and inhibition within and between cortical areas. The current work extends this approach to successfully model effects on both N400 amplitudes and behavior of word frequency, semantic richness, repetition, semantic and associative priming, and orthographic neighborhood size. The account is argued to be preferable to one based on "implicit semantic prediction error" (Rabovsky & McRae, 2014) for a number of reasons, the most fundamental of which is that the current model actually produces N400-like waveforms in its real-time activation dynamics. Copyright © 2016 Elsevier B.V. All rights reserved.

Real-time PCR detection of Plasmodium directly from whole blood and filter paper samples

PubMed Central

2011-01-01

Background Real-time PCR is a sensitive and specific method for the analysis of Plasmodium DNA. However, prior purification of genomic DNA from blood is necessary since PCR inhibitors and quenching of fluorophores from blood prevent efficient amplification and detection of PCR products. Methods Reagents designed to specifically overcome PCR inhibition and quenching of fluorescence were evaluated for real-time PCR amplification of Plasmodium DNA directly from blood. Whole blood from clinical samples and dried blood spots collected in the field in Colombia were tested. Results Amplification and fluorescence detection by real-time PCR were optimal with 40× SYBR® Green dye and 5% blood volume in the PCR reaction. Plasmodium DNA was detected directly from both whole blood and dried blood spots from clinical samples. The sensitivity and specificity ranged from 93-100% compared with PCR performed on purified Plasmodium DNA. Conclusions The methodology described facilitates high-throughput testing of blood samples collected in the field by fluorescence-based real-time PCR. This method can be applied to a broad range of clinical studies with the advantages of immediate sample testing, lower experimental costs and time-savings. PMID:21851640

Real-time multiplexed digital cavity-enhanced spectroscopy

DOE PAGES

Boyson, Toby K.; Dagdigian, Paul J.; Pavey, Karl D.; ...

2015-10-01

Cavity-enhanced spectroscopy is a sensitive optical absorption technique but one where the practical applications have been limited to studying small wavelength ranges. In addition, this Letter shows that wideband operation can be achieved by combining techniques usually reserved for the communications community with that of cavity-enhanced spectroscopy, producing a multiplexed real-time cavity-enhanced spectrometer. We use multiple collinear laser sources operating asynchronously and simultaneously while being detected on a single photodetector. This is synonymous with radio frequency (RF) cellular systems in which signals are detected on a single antenna but decoded uniquely. Here, we demonstrate results with spectra of methyl salicylatemore » and show parts-per-billion per root hertz sensitivity measured in real-time.« less

On-loom, real-time, noncontact detection of fabric defects by ultrasonic imaging.

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

Chien, H. T.

1998-09-08

A noncontact, on-loom ultrasonic inspection technique was developed for real-time 100% defect inspection of fabrics. A prototype was built and tested successfully on loom. The system is compact, rugged, low cost, requires minimal maintenance, is not sensitive to fabric color and vibration, and can easily be adapted to current loom configurations. Moreover, it can detect defects in both the pick and warp directions. The system is capable of determining the size, location, and orientation of each defect. To further improve the system, air-coupled transducers with higher efficiency and sensitivity need to be developed. Advanced detection algorithms also need to bemore » developed for better classification and categorization of defects in real-time.« less

Towards an active real-time THz camera: first realization of a hybrid system

NASA Astrophysics Data System (ADS)

May, T.; am Weg, C.; Alcin, A.; Hils, B.; Löffler, T.; Roskos, H. G.

2007-04-01

We report the realization of a hybrid system for stand-off THz reflectrometry measurements. The design combines the best of two worlds: the high radiation power of sub-THz micro-electronic emitters and the high sensitivity of coherent opto-electronic detection. Our system is based on a commercially available multiplied Gunn source with a cw output power of 0.6 mW at 0.65 THz. We combine it with electro-optic mixing with femtosecond light pulses in a ZnTe crystal. This scheme can be described as heterodyne detection with a Ti:sapphire fs-laser acting as local oscillator and therefore allows for phase-sensitive measurements. Example images of test objects are obtained with mechanical scanning optics and with measurement times per pixel as short as 10 ms. The test objects are placed at a distance of 1 m from the detector and also from the source. The results indicate diffraction-limited resolution. Different contrast mechanisms, based on absorption, scattering, and difference in optical thickness are employed. Our evaluation shows that it should be possible to realize a real-time multi-pixel detector with several hundreds of pixels and a dynamic range of at least two orders of magnitude in power.

Development and Validation of a Real-Time PCR Assay for Rapid Detection of Candida auris from Surveillance Samples

PubMed Central

Leach, L.; Zhu, Y.

2017-01-01

ABSTRACT Candida auris is an emerging multidrug-resistant yeast causing invasive health care-associated infection with high mortality worldwide. Rapid identification of C. auris is of primary importance for the implementation of public health measures to control the spread of infection. To achieve these goals, we developed and validated a TaqMan-based real-time PCR assay targeting the internal transcribed spacer 2 (ITS2) region of the ribosomal gene. The assay was highly specific, reproducible, and sensitive, with the detection limit of 1 C. auris CFU/PCR. The performance of the C. auris real-time PCR assay was evaluated by using 623 surveillance samples, including 365 patient swabs and 258 environmental sponges. Real-time PCR yielded positive results from 49 swab and 58 sponge samples, with 89% and 100% clinical sensitivity with regard to their respective culture-positive results. The real-time PCR also detected C. auris DNA from 1% and 12% of swab and sponge samples with culture-negative results, indicating the presence of dead or culture-impaired C. auris. The real-time PCR yielded results within 4 h of sample processing, compared to 4 to 14 days for culture, reducing turnaround time significantly. The new real-time PCR assay allows for accurate and rapid screening of C. auris and can increase effective control and prevention of this emerging multidrug-resistant fungal pathogen in health care facilities. PMID:29187562

Development and Validation of a Real-Time PCR Assay for Rapid Detection of Candida auris from Surveillance Samples.

PubMed

Leach, L; Zhu, Y; Chaturvedi, S

2018-02-01

Candida auris is an emerging multidrug-resistant yeast causing invasive health care-associated infection with high mortality worldwide. Rapid identification of C. auris is of primary importance for the implementation of public health measures to control the spread of infection. To achieve these goals, we developed and validated a TaqMan-based real-time PCR assay targeting the internal transcribed spacer 2 ( ITS 2) region of the ribosomal gene. The assay was highly specific, reproducible, and sensitive, with the detection limit of 1 C. auris CFU/PCR. The performance of the C. auris real-time PCR assay was evaluated by using 623 surveillance samples, including 365 patient swabs and 258 environmental sponges. Real-time PCR yielded positive results from 49 swab and 58 sponge samples, with 89% and 100% clinical sensitivity with regard to their respective culture-positive results. The real-time PCR also detected C. auris DNA from 1% and 12% of swab and sponge samples with culture-negative results, indicating the presence of dead or culture-impaired C. auris The real-time PCR yielded results within 4 h of sample processing, compared to 4 to 14 days for culture, reducing turnaround time significantly. The new real-time PCR assay allows for accurate and rapid screening of C. auris and can increase effective control and prevention of this emerging multidrug-resistant fungal pathogen in health care facilities. Copyright © 2018 Leach et al.

Real-time detection of antibiotic activity by measuring nanometer-scale bacterial deformation

NASA Astrophysics Data System (ADS)

Iriya, Rafael; Syal, Karan; Jing, Wenwen; Mo, Manni; Yu, Hui; Haydel, Shelley E.; Wang, Shaopeng; Tao, Nongjian

2017-12-01

Diagnosing antibiotic-resistant bacteria currently requires sensitive detection of phenotypic changes associated with antibiotic action on bacteria. Here, we present an optical imaging-based approach to quantify bacterial membrane deformation as a phenotypic feature in real-time with a nanometer scale (˜9 nm) detection limit. Using this approach, we found two types of antibiotic-induced membrane deformations in different bacterial strains: polymyxin B induced relatively uniform spatial deformation of Escherichia coli O157:H7 cells leading to change in cellular volume and ampicillin-induced localized spatial deformation leading to the formation of bulges or protrusions on uropathogenic E. coli CFT073 cells. We anticipate that the approach will contribute to understanding of antibiotic phenotypic effects on bacteria with a potential for applications in rapid antibiotic susceptibility testing.

Quantitative assessment of hematopoietic chimerism by quantitative real-time polymerase chain reaction of sequence polymorphism systems after hematopoietic stem cell transplantation.

PubMed

Qin, Xiao-ying; Li, Guo-xuan; Qin, Ya-zhen; Wang, Yu; Wang, Feng-rong; Liu, Dai-hong; Xu, Lan-ping; Chen, Huan; Han, Wei; Wang, Jing-zhi; Zhang, Xiao-hui; Li, Jin-lan; Li, Ling-di; Liu, Kai-yan; Huang, Xiao-jun

2011-08-01

Analysis of changes in recipient and donor hematopoietic cell origin is extremely useful to monitor the effect of hematopoietic stem cell transplantation (HSCT) and sequential adoptive immunotherapy by donor lymphocyte infusions. We developed a sensitive, reliable and rapid real-time PCR method based on sequence polymorphism systems to quantitatively assess the hematopoietic chimerism after HSCT. A panel of 29 selected sequence polymorphism (SP) markers was screened by real-time PCR in 101 HSCT patients with leukemia and other hematological diseases. The chimerism kinetics of bone marrow samples of 8 HSCT patients in remission and relapse situations were followed longitudinally. Recipient genotype discrimination was possible in 97.0% (98 of 101) with a mean number of 2.5 (1-7) informative markers per recipient/donor pair. Using serial dilutions of plasmids containing specific SP markers, the linear correlation (r) of 0.99, the slope between -3.2 and -3.7 and the sensitivity of 0.1% were proved reproducible. By this method, it was possible to very accurately detect autologous signals in the range from 0.1% to 30%. The accuracy of the method in the very important range of autologous signals below 5% was extraordinarily high (standard deviation <1.85%), which might significantly improve detection accuracy of changes in autologous signals early in the post-transplantation course of follow-up. The main advantage of the real-time PCR method over short tandem repeat PCR chimerism assays is the absence of PCR competition and plateau biases, with demonstrated greater sensitivity and linearity. Finally, we prospectively analyzed bone marrow samples of 8 patients who received allografts and presented the chimerism kinetics of remission and relapse situations that illustrated the sensitivity level and the promising clinical application of this method. This SP-based real-time PCR assay provides a rapid, sensitive, and accurate quantitative assessment of mixed chimerism that can be useful in predicting graft rejection and early relapse.

In vivo real-time cavitation imaging in moving organs

NASA Astrophysics Data System (ADS)

Arnal, B.; Baranger, J.; Demene, C.; Tanter, M.; Pernot, M.

2017-02-01

The stochastic nature of cavitation implies visualization of the cavitation cloud in real-time and in a discriminative manner for the safe use of focused ultrasound therapy. This visualization is sometimes possible with standard echography, but it strongly depends on the quality of the scanner, and is hindered by difficulty in discriminating from highly reflecting tissue signals in different organs. A specific approach would then permit clear validation of the cavitation position and activity. Detecting signals from a specific source with high sensitivity is a major problem in ultrasound imaging. Based on plane or diverging wave sonications, ultrafast ultrasonic imaging dramatically increases temporal resolution, and the larger amount of acquired data permits increased sensitivity in Doppler imaging. Here, we investigate a spatiotemporal singular value decomposition of ultrafast radiofrequency data to discriminate bubble clouds from tissue based on their different spatiotemporal motion and echogenicity during histotripsy. We introduce an automation to determine the parameters of this filtering. This method clearly outperforms standard temporal filtering techniques with a bubble to tissue contrast of at least 20 dB in vitro in a moving phantom and in vivo in porcine liver.

Development and evaluation of the quantitative real-time PCR assay in detection and typing of herpes simplex virus in swab specimens from patients with genital herpes.

PubMed

Liu, Junlian; Yi, Yong; Chen, Wei; Si, Shaoyan; Yin, Mengmeng; Jin, Hua; Liu, Jianjun; Zhou, Jinlian; Zhang, Jianzhong

2015-01-01

Genital herpes (GH), which is caused mainly by herpes simplex virus (HSV)-2 and HSV-1, remains a worldwide problem. Laboratory confirmation of GH is important, particularly as there are other conditions which present similarly to GH, while atypical presentations of GH also occur. Currently, virus culture is the classical method for diagnosis of GH, but it is time consuming and with low sensitivity. A major advance for diagnosis of GH is to use Real-time polymerase chain reaction (PCR). In this study, to evaluate the significance of the real-time PCR method in diagnosis and typing of genital HSV, the primers and probes targeted at HSV-1 DNA polymerase gene and HSV-2 glycoprotein D gene fraction were designed and applied to amplify DNA from HSV-1 or HSV-2 by employing the real-time PCR technique. Then the PCR reaction system was optimized and evaluated. HSV in swab specimens from patients with genital herpes was detected by real-time PCR. The real-time PCR assay showed good specificity for detection and typing of HSV, with good linear range (5×10(2)~5×10(8) copies/ml, r=0.997), a sensitivity of 5×10(2) copies/ml, and good reproducibility (intra-assay coefficients of variation 2.29% and inter-assay coefficients of variation 4.76%). 186 swab specimens were tested for HSV by real-time PCR, and the positive rate was 23.7% (44/186). Among the 44 positive specimens, 8 (18.2%) were positive for HSV-1 with a viral load of 8.5546×10(6) copies/ml and 36 (81.2%) were positive for HSV-2 with a viral load of 1.9861×10(6) copies/ml. It is concluded that the real-time PCR is a specific, sensitive and rapid method for the detection and typing of HSV, which can be widely used in clinical diagnosis of GH.

Versatile analog pulse height computer performs real-time arithmetic operations

NASA Technical Reports Server (NTRS)

Brenner, R.; Strauss, M. G.

1967-01-01

Multipurpose analog pulse height computer performs real-time arithmetic operations on relatively fast pulses. This computer can be used for identification of charged particles, pulse shape discrimination, division of signals from position sensitive detectors, and other on-line data reduction techniques.

BAG3 protects against hyperthermic stress by modulating NF-κB and ERK activities in human retinoblastoma cells.

PubMed

Yunoki, Tatsuya; Tabuchi, Yoshiaki; Hayashi, Atsushi; Kondo, Takashi

2015-03-01

BCL2-associated athanogene 3 (BAG3), a co-chaperone of HSP70, is a cytoprotective and anti-apoptotic protein that acts against various stresses, including heat stress. Here, we examined the effect of BAG3 on the sensitivity of human retinoblastoma cells to hyperthermia (HT). We examined the effects of BAG3 knockdown on the sensitivity of Y79 and WERI-Rb-1cells to HT (44 °C, 1 h) by evaluating apoptosis and cell proliferation using western blotting, real-time quantitative PCR (qPCR), flow cytometry, and a WST-8 assay kit. Furthermore, we examined the effects of activating nuclear factor-kappa B (NF-κB) and extracellular signal-regulated kinase (ERK) using western blotting and real time qPCR. HT induced considerable apoptosis along with the activation of caspase-3 and chromatin condensation. The sensitivity of Y79 and WERI-Rb-1 cells to HT was significantly enhanced by BAG3 knockdown. Compared to HT alone, the combination of BAG3 knockdown and HT reduced phosphorylation of the inhibitors of kappa B α (IκBα) and p65, a subunit of NF-κB, and degraded IκB kinase γ (IKKγ) during the recovery period after HT. Furthermore, BAG3 knockdown increased the HT-induced phosphorylation of ERK after HT treatment, and the ERK inhibitor U0126 significantly improved the viability of the cells treated with a combination of BAG3 knockdown and HT. The silencing of BAG3 seems to enhance the effects of HT, at least in part, by maintaining HT-induced inactivity of NF-κB and the phosphorylation of ERK. These findings indicate that BAG3 may be a potential molecular target for modifying the outcomes of HT in retinoblastoma.

Der p 1 suppresses indoleamine 2, 3-dioxygenase in dendritic cells from house dust mite-sensitive patients with asthma.

PubMed

Maneechotesuwan, Kittipong; Wamanuttajinda, Valla; Kasetsinsombat, Kanda; Huabprasert, Sukit; Yaikwawong, Metha; Barnes, Peter J; Wongkajornsilp, Adisak

2009-01-01

Indoleamine 2, 3-dioxygenase (IDO), a tryptophan-degrading enzyme in dendritic cells (DCs), mediates an immunosuppressive effect on activated T lymphocytes. However, little is known about the effect of Der p 1 on IDO in human DCs. The aim was to investigate the effect of Der p 1 on the expression and activity of IDO in monocyte-derived DCs from house dust mite (HDM)-sensitive patients with asthma. Using real-time RT-PCR and HPLC, the expression and activity of IDO were assessed in TNF-alpha-induced mature DCs from HDM-sensitive and nonatopic patients with asthma in response to Der p 1 exposure ex vivo. We also monitored the alteration of IDO activity in Der p 1-pulsed DCs after the coincubation with autologous T cells. With a reliance on its protease activity, Der p 1 suppressed functional IDO in DCs from HDM-sensitive patients with asthma but enhanced IDO activity in DCs from nonatopic patients with asthma. This suppression was maintained by the reciprocally induced IL-4 from the coculturing autologous HDM-sensitive T cells. Conversely, the upregulation of IDO activity in Der p 1-pulsed DCs was maintained by IFN-gamma released from autologous nonatopic T cells and the regulatory T-cell subset. Der p 1 pulsation to sensitive DCs failed to raise regulatory T cells but raised progenitor fractions from cloned HDM-sensitive CD4(+) cells through direct contact and soluble mediators. House dust mite-sensitive DCs exposed to Der p 1 downregulated IDO activity and tipped the T(H)1/T(H)2 cytokine balance toward IL-4, resulting in sustainable IDO suppression.

Comparison of the analytical and clinical performances of Abbott RealTime High Risk HPV, Hybrid Capture 2, and DNA Chip assays in gynecology patients.

PubMed

Park, Seungman; Kang, Youjin; Kim, Dong Geun; Kim, Eui-Chong; Park, Sung Sup; Seong, Moon-Woo

2013-08-01

The detection of high-risk (HR) HPV in cervical cancer screening is important for early diagnosis of cervical cancer or pre-cancerous lesions. We evaluated the analytical and clinical performances of 3 HR HPV assays in Gynecology patients. A total of 991 specimens were included in this study: 787 specimens for use with a Hybrid Capture 2 (HC2) and 204 specimens for a HPV DNA microarray (DNA Chip). All specimens were tested using an Abbott RealTime High Risk HPV assay (Real-time HR), PGMY PCR, and sequence analysis. Clinical sensitivities for severe abnormal cytology (severe than high-grade squamous intraepithelial lesion) were 81.8% for Real-time HR, 77.3% for HC2, and 66.7% for DNA Chip, and clinical sensitivities for severe abnormal histology (cervical intraepithelial neoplasia grade 2+) were 91.7% for HC2, 87.5% for Real-time HR, and 73.3% for DNA Chip. As compared to results of the sequence analysis, HC2, Real-time HR, and DNA Chip showed concordance rates of 94.3% (115/122), 90.0% (117/130), and 61.5% (16/26), respectively. The HC2 assay and Real-time HR assay showed comparable results to each other in both clinical and analytical performances, while the DNA Chip assay showed poor clinical and analytical performances. The Real-time HR assay can be a good alternative option for HR HPV testing with advantages of allowing full automation and simultaneous genotyping of HR types 16 and 18. Copyright © 2013 Elsevier Inc. All rights reserved.

Structure, interaction and real-time monitoring of the enzymatic reaction of wild-type APOBEC3G.

PubMed

Furukawa, Ayako; Nagata, Takashi; Matsugami, Akimasa; Habu, Yuichirou; Sugiyama, Ryuichi; Hayashi, Fumiaki; Kobayashi, Naohiro; Yokoyama, Shigeyuki; Takaku, Hiroshi; Katahira, Masato

2009-02-18

Human APOBEC3G exhibits anti-human immunodeficiency virus-1 (HIV-1) activity by deaminating cytidines of the minus strand of HIV-1. Here, we report a solution structure of the C-terminal deaminase domain of wild-type APOBEC3G. The interaction with DNA was examined. Many differences in the interaction were found between the wild type and recently studied mutant APOBEC3Gs. The position of the substrate cytidine, together with that of a DNA chain, in the complex, was deduced. Interestingly, the deamination reaction of APOBEC3G was successfully monitored using NMR signals in real time. Real-time monitoring has revealed that the third cytidine of the d(CCCA) segment is deaminated at an early stage and that then the second one is deaminated at a late stage, the first one not being deaminated at all. This indicates that the deamination is carried out in a strict 3' --> 5' order. Virus infectivity factor (Vif) of HIV-1 counteracts the anti-HIV-1 activity of APOBEC3G. The structure of the N-terminal domain of APOBEC3G, with which Vif interacts, was constructed with homology modelling. The structure implies the mechanism of species-specific sensitivity of APOBEC3G to Vif action.

Structure, interaction and real-time monitoring of the enzymatic reaction of wild-type APOBEC3G

PubMed Central

Furukawa, Ayako; Nagata, Takashi; Matsugami, Akimasa; Habu, Yuichirou; Sugiyama, Ryuichi; Hayashi, Fumiaki; Kobayashi, Naohiro; Yokoyama, Shigeyuki; Takaku, Hiroshi; Katahira, Masato

2009-01-01

Human APOBEC3G exhibits anti-human immunodeficiency virus-1 (HIV-1) activity by deaminating cytidines of the minus strand of HIV-1. Here, we report a solution structure of the C-terminal deaminase domain of wild-type APOBEC3G. The interaction with DNA was examined. Many differences in the interaction were found between the wild type and recently studied mutant APOBEC3Gs. The position of the substrate cytidine, together with that of a DNA chain, in the complex, was deduced. Interestingly, the deamination reaction of APOBEC3G was successfully monitored using NMR signals in real time. Real-time monitoring has revealed that the third cytidine of the d(CCCA) segment is deaminated at an early stage and that then the second one is deaminated at a late stage, the first one not being deaminated at all. This indicates that the deamination is carried out in a strict 3′ → 5′ order. Virus infectivity factor (Vif) of HIV-1 counteracts the anti-HIV-1 activity of APOBEC3G. The structure of the N-terminal domain of APOBEC3G, with which Vif interacts, was constructed with homology modelling. The structure implies the mechanism of species-specific sensitivity of APOBEC3G to Vif action. PMID:19153609

Feature Acquisition with Imbalanced Training Data

NASA Technical Reports Server (NTRS)

Thompson, David R.; Wagstaff, Kiri L.; Majid, Walid A.; Jones, Dayton L.

2011-01-01

This work considers cost-sensitive feature acquisition that attempts to classify a candidate datapoint from incomplete information. In this task, an agent acquires features of the datapoint using one or more costly diagnostic tests, and eventually ascribes a classification label. A cost function describes both the penalties for feature acquisition, as well as misclassification errors. A common solution is a Cost Sensitive Decision Tree (CSDT), a branching sequence of tests with features acquired at interior decision points and class assignment at the leaves. CSDT's can incorporate a wide range of diagnostic tests and can reflect arbitrary cost structures. They are particularly useful for online applications due to their low computational overhead. In this innovation, CSDT's are applied to cost-sensitive feature acquisition where the goal is to recognize very rare or unique phenomena in real time. Example applications from this domain include four areas. In stream processing, one seeks unique events in a real time data stream that is too large to store. In fault protection, a system must adapt quickly to react to anticipated errors by triggering repair activities or follow- up diagnostics. With real-time sensor networks, one seeks to classify unique, new events as they occur. With observational sciences, a new generation of instrumentation seeks unique events through online analysis of large observational datasets. This work presents a solution based on transfer learning principles that permits principled CSDT learning while exploiting any prior knowledge of the designer to correct both between-class and withinclass imbalance. Training examples are adaptively reweighted based on a decomposition of the data attributes. The result is a new, nonparametric representation that matches the anticipated attribute distribution for the target events.

Drosophila Bitter Taste(s)

PubMed Central

French, Alice; Ali Agha, Moutaz; Mitra, Aniruddha; Yanagawa, Aya; Sellier, Marie-Jeanne; Marion-Poll, Frédéric

2015-01-01

Most animals possess taste receptors neurons detecting potentially noxious compounds. In humans, the ligands which activate these neurons define a sensory space called “bitter”. By extension, this term has been used in animals and insects to define molecules which induce aversive responses. In this review, based on our observations carried out in Drosophila, we examine how bitter compounds are detected and if bitter-sensitive neurons respond only to molecules bitter to humans. Like most animals, flies detect bitter chemicals through a specific population of taste neurons, distinct from those responding to sugars or to other modalities. Activating bitter-sensitive taste neurons induces aversive reactions and inhibits feeding. Bitter molecules also contribute to the suppression of sugar-neuron responses and can lead to a complete inhibition of the responses to sugar at the periphery. Since some bitter molecules activate bitter-sensitive neurons and some inhibit sugar detection, bitter molecules are represented by two sensory spaces which are only partially congruent. In addition to molecules which impact feeding, we recently discovered that the activation of bitter-sensitive neurons also induces grooming. Bitter-sensitive neurons of the wings and of the legs can sense chemicals from the gram negative bacteria, Escherichia coli, thus adding another biological function to these receptors. Bitter-sensitive neurons of the proboscis also respond to the inhibitory pheromone, 7-tricosene. Activating these neurons by bitter molecules in the context of sexual encounter inhibits courting and sexual reproduction, while activating these neurons with 7-tricosene in a feeding context will inhibit feeding. The picture that emerges from these observations is that the taste system is composed of detectors which monitor different “categories” of ligands, which facilitate or inhibit behaviors depending on the context (feeding, sexual reproduction, hygienic behavior), thus considerably extending the initial definition of “bitter” tasting. PMID:26635553

The viability of outercourse for HIV prevention within the Puerto Rican context.

PubMed

Norman, Lisa R

2010-01-01

As the number of HIV/AIDS cases continues to increase in Puerto Rico, outercourse, or non-penetrative sexual activities, may be one alternative for healthy sexual living for persons living with or at risk for HIV/AIDS. Between April and August 2006, we surveyed 1138 women living in low-income housing in Ponce, PR on their attitudes toward and participation in outercourse activities. The majority of the sample were aged >25 years (80.2%), with a mean sample age of 36.77 (SD = 12.31). Approximately one half (49.8%) of the women in the sample were legally married or involved in a common-law relationship. Mutual masturbation and the use of sex toys were viewed as "real sex" by only 33% and 16%, respectively, of the women surveyed. A slight majority had at least a high school education (57.5%). Of those with a steady sex partner in the previous 12 months, 47% engaged in mutual masturbation, and 17% used sex toys. Of those with a non-steady sex partner in the previous 12 months, 41% engaged in mutual masturbation, and 14% used sex toys. Logistic regressions indicated that persons who perceived mutual masturbation and the use of sex toys as real sex were more likely than those who did not perceive them to be so to engage in either or both behaviors with their most recent steady sex partner (OR = 4.5, CI =3.3-6.2 and OR=18.11, CI = 11.5-28.6, respectively); the same relationship emerged with their most recent non-steady sex partner (OR = 4.0, CI = 1.9-8.3 and OR = 15.9, CI = 5.3-47.4). The levels of participation in outercourse were low across the sample; also low was the perception of outercourse as being real sex. Outercourse appears to be, primarily, a precursor to penetrative sex, especially with steady sex partners. If culturally sensitive prevention messages were to promote outercourse as real sex and as an ultimate sexual goal, couples might be able to maintain an intimate, yet safe, sexual relationship. Outercourse should not be promoted as the only option for safer sex relationships but instead in the context of a comprehensive prevention message, which would also include protected sexual intercourse for those who choose to engage in penetrative activities.

Synchronization and fault-masking in redundant real-time systems

NASA Technical Reports Server (NTRS)

Krishna, C. M.; Shin, K. G.; Butler, R. W.

1983-01-01

A real time computer may fail because of massive component failures or not responding quickly enough to satisfy real time requirements. An increase in redundancy - a conventional means of improving reliability - can improve the former but can - in some cases - degrade the latter considerably due to the overhead associated with redundancy management, namely the time delay resulting from synchronization and voting/interactive consistency techniques. The implications of synchronization and voting/interactive consistency algorithms in N-modular clusters on reliability are considered. All these studies were carried out in the context of real time applications. As a demonstrative example, we have analyzed results from experiments conducted at the NASA Airlab on the Software Implemented Fault Tolerance (SIFT) computer. This analysis has indeed indicated that in most real time applications, it is better to employ hardware synchronization instead of software synchronization and not allow reconfiguration.

Time-Dependent Effects of Prazosin on the Development of Methamphetamine Conditioned Hyperactivity and Context-Specific Sensitization in Mice

PubMed Central

White, André O.; Rauhut, Anthony S.

2014-01-01

The present experiments examined the effects of prazosin, a selective α1-adrenergic receptor antagonist, on the development of methamphetamine conditioned hyperactivity and context-specific sensitization. Mice received an injection of vehicle (distilled water) or prazosin (0.5, 1.0 or 2.0 mg/kg) 30 minutes prior to a second injection of vehicle (saline) or methamphetamine (1.0 mg/kg) during the conditioning sessions (Experiment 1). Following the conditioning sessions, mice were tested for conditioned hyperactivity and then tested for context-specific sensitization. In subsequent experiments, mice received an injection of vehicle (distilled water) or prazosin (2.0 mg/kg) immediately (Experiment 2) or 24 hours (Experiment 3) after the conditioning sessions and then tested for conditioned hyperactivity and context-specific sensitization. Prazosin dose-dependently blocked the development of methamphetamine conditioned hyperactivity and context-specific sensitization when administered prior to the methamphetamine during the conditioning phase; however nonspecific motor impairments also were observed (Experiment 1). Immediate (Experiment 2), but not the 24-hour delay (Experiment 3), post-session administration of prazosin attenuated the development of methamphetamine conditioned hyperactivity and context-specific sensitization. Nonspecific motor impairments were not observed in these latter experiments. Collectively, these results suggest that the α1-adrenergic receptor mediates the development of methamphetamine-conditioned hyperactivity and context-specific sensitization, perhaps by altering memory consolidation and/or reconsolidation processes. PMID:24487011

Colonic lesion characterization in inflammatory bowel disease: A systematic review and meta-analysis

PubMed Central

Lord, Richard; Burr, Nicholas E; Mohammed, Noor; Subramanian, Venkataraman

2018-01-01

AIM To perform a systematic review and meta-analysis for the diagnostic accuracy of in vivo lesion characterization in colonic inflammatory bowel disease (IBD), using optical imaging techniques, including virtual chromoendoscopy (VCE), dye-based chromoendoscopy (DBC), magnification endoscopy and confocal laser endomicroscopy (CLE). METHODS We searched Medline, Embase and the Cochrane library. We performed a bivariate meta-analysis to calculate the pooled estimate sensitivities, specificities, positive and negative likelihood ratios (+LHR, -LHR), diagnostic odds ratios (DOR), and area under the SROC curve (AUSROC) for each technology group. A subgroup analysis was performed to investigate differences in real-time non-magnified Kudo pit patterns (with VCE and DBC) and real-time CLE. RESULTS We included 22 studies [1491 patients; 4674 polyps, of which 539 (11.5%) were neoplastic]. Real-time CLE had a pooled sensitivity of 91% (95%CI: 66%-98%), specificity of 97% (95%CI: 94%-98%), and an AUSROC of 0.98 (95%CI: 0.97-0.99). Magnification endoscopy had a pooled sensitivity of 90% (95%CI: 77%-96%) and specificity of 87% (95%CI: 81%-91%). VCE had a pooled sensitivity of 86% (95%CI: 62%-95%) and specificity of 87% (95%CI: 72%-95%). DBC had a pooled sensitivity of 67% (95%CI: 44%-84%) and specificity of 86% (95%CI: 72%-94%). CONCLUSION Real-time CLE is a highly accurate technology for differentiating neoplastic from non-neoplastic lesions in patients with colonic IBD. However, most CLE studies were performed by single expert users within tertiary centres, potentially confounding these results. PMID:29563760

The evaluation of three diagnostic tests for the detection of equine influenza nucleoprotein in nasal swabs.

PubMed

Galvin, Pamela; Gildea, Sarah; Nelly, Maura; Quinlivan, Michelle; Arkins, Sean; Walsh, Cathal; Cullinane, Ann

2014-05-01

Equine influenza (EI) is a highly contagious respiratory disease of horses. The aim of this study was to evaluate two rapid antigen detection kits (Directigen or DFA, and Espline) and a commercial ELISA for the detection of EI nucleoprotein in nasal swabs. Nasal swab samples from naturally and experimentally infected horses were used to compare the sensitivity and specificity of these assays to virus isolation (VI) and real-time RT-PCR. If real-time RT-PCR was considered as the gold standard, the sensitivity of the other tests in field samples was 68% (DFA), 35% (ELISA), 29% (Espline), and 9% (VI). These tests had 100% specificity when compared to real-time RT-PCR. A receiver operating characteristic (ROC) curve indicated that decreasing the cutoff of the ELISA would increase sensitivity with some loss of specificity. In samples from experimentally infected horses, the sensitivity of the tests compared with real-time RT-PCR was 69% (VI), 27% (DFA), 6% (Espline), and 2% (ELISA). The specificity was 100% for Espline and ELISA and 95% for VI and DFA. This study illustrated that DFA is the most sensitive antigen detection test evaluated for the diagnosis of EI and that it can detect virus in some subclinical infected and vaccinated horses. The results suggest that DFA is a useful adjunct to laboratory tests and may be effective as a screening test in a quarantine station or similar facility where horses are monitored daily. © 2014 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Rectal swab sampling followed by an enrichment culture-based real-time PCR assay to detect Salmonella enterocolitis in children.

PubMed

Lin, L-H; Tsai, C-Y; Hung, M-H; Fang, Y-T; Ling, Q-D

2011-09-01

Although routine bacterial culture is the traditional reference standard method for the detection of Salmonella infection in children with diarrhoea, it is a time-consuming procedure that usually only gives results after 3-4 days. Some molecular detection methods can improve the turn-around time to within 24 h, but these methods are not applied directly from stool or rectal swab specimens as routine diagnostic methods for the detection of gastrointestinal pathogens. In this study, we tested the feasibility of a bacterial enrichment culture-based real-time PCR assay method for detecting and screening for diarrhoea in children caused by Salmonella. Our results showed that the minimum real-time PCR assay time required to detect enriched bacterial culture from a swab was 3 h. In all children with suspected Salmonella diarrhoea, the enrichment culture-based real-time PCR achieved 85.4% sensitivity and 98.1% specificity, as compared with the 53.7% sensitivity and 100% specificity of detection with the routine bacterial culture method. We suggest that rectal swab sampling followed by enrichment culture-based real-time PCR is suitable as a rapid method for detecting and screening for Salmonella in paediatric patients. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

Real-time prediction of mediastinal lymph node malignancy by endobronchial ultrasound.

PubMed

Shafiek, Hanaa; Fiorentino, Federico; Peralta, Alejandro David; Serra, Enrique; Esteban, Blanca; Martinez, Rocío; Noguera, Maria Angels; Moyano, Pere; Sala, Ernest; Sauleda, Jaume; Cosío, Borja G

2014-06-01

To evaluate the utility of different ultrasonographic (US) features in differentiating benign and malignant lymph node (LN) by endobronchial ultrasound (EBUS) and validate a score for real-time clinical application. 208 mediastinal LN acquired from 141 patients were analyzed. Six different US criteria were evaluated (short axis ≥10 mm, shape, margin, echogenicity, and central hilar structure [CHS], and presence of hyperechoic density) by two observers independently. A simplified score was generated where the presence of margin distinction, round shape and short axis ≥10 mm were scored as 1 and heterogeneous echogenicity and absence of CHS were scored as 1.5. The score was evaluated prospectively for real-time clinical application in 65 LN during EBUS procedure in 39 patients undertaken by two experienced operators. These criteria were correlated with the histopathological results and the sensitivity, specificity, positive and negative predictive values (PPV and NPV) were calculated. Both heterogenicity and absence of CHS had the highest sensitivity and NPV (≥90%) for predicting LN malignancy with acceptable inter-observer agreement (92% and 87% respectively). On real-time application, the sensitivity and specificity of the score >5 were 78% and 86% respectively; only the absence of CHS, round shape and size of LN were significantly associated with malignant LN. Combination of different US criteria can be useful for prediction of mediastinal LN malignancy and valid for real-time clinical application. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.

Analytical Performances of Human Immunodeficiency Virus Type 1 RNA-Based Amplix® Real-Time PCR Platform for HIV-1 RNA Quantification

PubMed Central

Mboumba Bouassa, Ralph-Sydney; Jenabian, Mohammad-Ali; Wolyec, Serge Tonen; Robin, Leman; Matta, Mathieu; Longo, Jean de Dieu; Grésenguet, Gérard; Andreoletti, Laurent; Bélec, Laurent

2016-01-01

Objectives. We evaluated the performances of Amplix real-time PCR platform developed by Biosynex (Strasbourg, France), combining automated station extraction (Amplix station 16 Dx) and real-time PCR (Amplix NG), for quantifying plasma HIV-1 RNA by lyophilized HIV-1 RNA-based Amplix reagents targeting gag and LTR, using samples from HIV-1-infected adults from Central African Republic. Results. Amplix real-time PCR assay showed low limit of detection (28 copies/mL), across wide dynamic range (1.4–10 log copies/mL), 100% sensitivity and 99% specificity, high reproducibility, and accuracy with mean bias < 5%. The assay showed excellent correlations and concordance of 95.3% with the reference HIV-1 RNA load assay (Roche), with mean absolute bias of +0.097 log copies/mL by Bland-Altman analysis. The assay was able to detect and quantify the most prevalent HIV-1 subtype strains and the majority of non-B subtypes, CRFs of HIV-1 group M, and HIV-1 groups N and O circulating in Central Africa. The Amplix assay showed 100% sensitivity and 99.6% specificity to diagnose virological failure in clinical samples from antiretroviral drug-experienced patients. Conclusions. The HIV-1 RNA-based Amplix real-time PCR platform constitutes sensitive and reliable system for clinical monitoring of HIV-1 RNA load in HIV-1-infected children and adults, particularly adapted to intermediate laboratory facilities in sub-Saharan Africa. PMID:28050283

Novel and highly sensitive sybr® green real-time pcr for poxvirus detection in odontocete cetaceans.

PubMed

Sacristán, Carlos; Luiz Catão-Dias, José; Ewbank, Ana Carolina; Machado, Eduardo Ferreira; Neves, Elena; Santos-Neto, Elitieri Batista; Azevedo, Alexandre; Laison-Brito, José; De Castilho, Pedro Volkmer; Daura-Jorge, Fábio Gonçalves; Simões-Lopes, Paulo César; Carballo, Matilde; García-Párraga, Daniel; Manuel Sánchez-Vizcaíno, José; Esperón, Fernando

2018-06-08

Poxviruses are emerging pathogens in cetaceans, temporarily named 'Cetaceanpoxvirus' (CePV, family Poxviridae), classified into two main lineages: CePV-1 in odontocetes and CePV-2 in mysticetes. Only a few studies performed the molecular detection of CePVs, based on DNA-polymerase gene and/or DNA-topoisomerase I gene amplification. Herein we describe a new real-time PCR assay based on SYBR ® Green and a new primer set to detect a 150 bp fragment of CePV DNA-polymerase gene, also effective for conventional PCR detection. The novel real-time PCR was able to detect 5 up to 5 × 10 6 copies per reaction of a cloned positive control. Both novel PCR methods were 1000 to 100,000-fold more sensitive than those previously described in the literature. Samples of characteristic poxvirus skin lesions ('tattoo') from one Risso's dolphin (Grampus griseus), two striped dolphins (Stenella coeruleoalba) and two Guiana dolphins (Sotalia guianensis) were all positive to both our novel real time- and conventional PCR methods, even though three of these animals (a Risso's dolphin, a striped dolphin, and a Guiana dolphin) were previously negative to the conventional PCRs previously available. To our knowledge, this is the first real-time PCR detection method for Cetaceanpoxvirus, a much more sensitive tool for the detection of CePV-1 infections. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparative analysis of detection methods for congenital cytomegalovirus infection in a Guinea pig model.

PubMed

Park, Albert H; Mann, David; Error, Marc E; Miller, Matthew; Firpo, Matthew A; Wang, Yong; Alder, Stephen C; Schleiss, Mark R

2013-01-01

To assess the validity of the guinea pig as a model for congenital cytomegalovirus (CMV) infection by comparing the effectiveness of detecting the virus by real-time polymerase chain reaction (PCR) in blood, urine, and saliva. Case-control study. Academic research. Eleven pregnant Hartley guinea pigs. Blood, urine, and saliva samples were collected from guinea pig pups delivered from pregnant dams inoculated with guinea pig CMV. These samples were then evaluated for the presence of guinea pig CMV by real-time PCR assuming 100% transmission. Thirty-one pups delivered from 9 inoculated pregnant dams and 8 uninfected control pups underwent testing for guinea pig CMV and for auditory brainstem response hearing loss. Repeated-measures analysis of variance demonstrated no statistically significantly lower weight for the infected pups compared with the noninfected control pups. Six infected pups demonstrated auditory brainstem response hearing loss. The sensitivity and specificity of the real-time PCR assay on saliva samples were 74.2% and 100.0%, respectively. The sensitivity of the real-time PCR on blood and urine samples was significantly lower than that on saliva samples. Real-time PCR assays of blood, urine, and saliva revealed that saliva samples show high sensitivity and specificity for detecting congenital CMV infection in guinea pigs. This finding is consistent with recent screening studies in human newborns. The guinea pig may be a good animal model in which to compare different diagnostic assays for congenital CMV infection.

Real-time QCM-D monitoring of cancer cell death early events in a dynamic context.

PubMed

Nowacki, Laetitia; Follet, Julie; Vayssade, Muriel; Vigneron, Pascale; Rotellini, Laura; Cambay, Florian; Egles, Christophe; Rossi, Claire

2015-02-15

Since a few years, the acoustic sensing of whole cell is the focus of increasing interest for monitoring the cytoskeletal cellular response to morphological modulators. We aimed at illustrating the potentialities of the quartz crystal microbalance with dissipation (QCM-D) technique for the real-time detection of the earliest morphological changes that occur at the cell-substrate interface during programmed cell death. Human breast cancer cells (MCF-7) grown on serum protein-coated gold sensors were placed in dynamic conditions under a continuous medium flow. The mass and viscoelasticity changes of the cells were tracked by monitoring the frequency and dissipation shifts during the first 4h of cell exposure to staurosporine, a well-known apoptosis inducer. We have identified a QCM-D signature characteristic of morphological modifications and cell detachment from the sensing surface that are related to the pro-apoptotic treatment. In particular, for low staurosporine doses below 1 µM, we showed that recording the dissipation shift allows to detect an early cell response which is undetectable after the same duration by the classical analytical techniques in cell biology. Furthermore, this sensing method allows quantifying the efficiency of the drug effect in less than 4h without requiring labeling and without interfering in the system, thus preventing any loss of information. In the actual context of targeted cancer therapy development, we believe that these results bring new insights in favor of the use of the non invasive QCM-D technique for quickly probing the cancer cell sensitivity to death inducer drugs. Copyright © 2014 Elsevier B.V. All rights reserved.

Avian influenza virus detection and quantitation by real-time RT-PCR

USDA-ARS?s Scientific Manuscript database

Real-time RT-PCR (rRT-PCR) has been used for avian influenza virus (AIV) detection since the early 2000’s for routine surveillance, during outbreaks and for research. Some of the advantages of rRT-PCR are: high sensitivity, high specificity, rapid time-to-result, scalability, cost, and its inherentl...

Reliability of fitness tests using methods and time periods common in sport and occupational management.

PubMed

Burnstein, Bryan D; Steele, Russell J; Shrier, Ian

2011-01-01

Fitness testing is used frequently in many areas of physical activity, but the reliability of these measurements under real-world, practical conditions is unknown. To evaluate the reliability of specific fitness tests using the methods and time periods used in the context of real-world sport and occupational management. Cohort study. Eighteen different Cirque du Soleil shows. Cirque du Soleil physical performers who completed 4 consecutive tests (6-month intervals) and were free of injury or illness at each session (n = 238 of 701 physical performers). Performers completed 6 fitness tests on each assessment date: dynamic balance, Harvard step test, handgrip, vertical jump, pull-ups, and 60-second jump test. We calculated the intraclass coefficient (ICC) and limits of agreement between baseline and each time point and the ICC over all 4 time points combined. Reliability was acceptable (ICC > 0.6) over an 18-month time period for all pairwise comparisons and all time points together for the handgrip, vertical jump, and pull-up assessments. The Harvard step test and 60-second jump test had poor reliability (ICC < 0.6) between baseline and other time points. When we excluded the baseline data and calculated the ICC for 6-month, 12-month, and 18-month time points, both the Harvard step test and 60-second jump test demonstrated acceptable reliability. Dynamic balance was unreliable in all contexts. Limit-of-agreement analysis demonstrated considerable intraindividual variability for some tests and a learning effect by administrators on others. Five of the 6 tests in this battery had acceptable reliability over an 18-month time frame, but the values for certain individuals may vary considerably from time to time for some tests. Specific tests may require a learning period for administrators.

A sensitive two-photon probe to selectively detect monoamine oxidase B activity in Parkinson’s disease models

NASA Astrophysics Data System (ADS)

Li, Lin; Zhang, Cheng-Wu; Chen, Grace Y. J.; Zhu, Biwei; Chai, Chou; Xu, Qing-Hua; Tan, Eng-King; Zhu, Qing; Lim, Kah-Leong; Yao, Shao Q.

2014-02-01

The unusually high MAO-B activity consistently observed in Parkinson’s disease (PD) patients has been proposed as a biomarker; however, this has not been realized due to the lack of probes suitable for MAO-B-specific detection in live cells/tissues. Here we report the first two-photon, small molecule fluorogenic probe (U1) that enables highly sensitive/specific and real-time imaging of endogenous MAO-B activities across biological samples. We also used U1 to confirm the reported inverse relationship between parkin and MAO-B in PD models. With no apparent toxicity, U1 may be used to monitor MAO-B activities in small animals during disease development. In clinical samples, we find elevated MAO-B activities only in B lymphocytes (not in fibroblasts), hinting that MAO-B activity in peripheral blood cells might be an accessible biomarker for rapid detection of PD. Our results provide important starting points for using small molecule imaging techniques to explore MAO-B at the organism level.

A sensitive two-photon probe to selectively detect monoamine oxidase B activity in Parkinson's disease models.

PubMed

Li, Lin; Zhang, Cheng-Wu; Chen, Grace Y J; Zhu, Biwei; Chai, Chou; Xu, Qing-Hua; Tan, Eng-King; Zhu, Qing; Lim, Kah-Leong; Yao, Shao Q

2014-01-01

The unusually high MAO-B activity consistently observed in Parkinson's disease (PD) patients has been proposed as a biomarker; however, this has not been realized due to the lack of probes suitable for MAO-B-specific detection in live cells/tissues. Here we report the first two-photon, small molecule fluorogenic probe (U1) that enables highly sensitive/specific and real-time imaging of endogenous MAO-B activities across biological samples. We also used U1 to confirm the reported inverse relationship between parkin and MAO-B in PD models. With no apparent toxicity, U1 may be used to monitor MAO-B activities in small animals during disease development. In clinical samples, we find elevated MAO-B activities only in B lymphocytes (not in fibroblasts), hinting that MAO-B activity in peripheral blood cells might be an accessible biomarker for rapid detection of PD. Our results provide important starting points for using small molecule imaging techniques to explore MAO-B at the organism level.

Sample pooling for real-time PCR detection and virulence determination of the footrot pathogen Dichelobacter nodosus.

PubMed

Frosth, Sara; König, Ulrika; Nyman, Ann-Kristin; Aspán, Anna

2017-09-01

Dichelobacter nodosus is the principal cause of ovine footrot and strain virulence is an important factor in disease severity. Therefore, detection and virulence determination of D. nodosus is important for proper diagnosis of the disease. Today this is possible by real-time PCR analysis. Analysis of large numbers of samples is costly and laborious; therefore, pooling of individual samples is common in surveillance programs. However, pooling can reduce the sensitivity of the method. The aim of this study was to develop a pooling method for real-time PCR analysis that would allow sensitive detection and simultaneous virulence determination of D. nodosus. A total of 225 sheep from 17 flocks were sampled using ESwabs within the Swedish Footrot Control Program in 2014. Samples were first analysed individually and then in pools of five by real-time PCR assays targeting the 16S rRNA and aprV2/B2 genes of D. nodosus. Each pool consisted of four negative and one positive D. nodosus samples with varying amounts of the bacterium. In the individual analysis, 61 (27.1%) samples were positive in the 16S rRNA and the aprV2/B2 PCR assays and 164 (72.9%) samples were negative. All samples positive in the aprV2/B2 PCR-assay were of aprB2 variant. The pooled analysis showed that all 41 pools were also positive for D. nodosus 16S rRNA and the aprB2 variant. The diagnostic sensitivity for pooled and individual samples was therefore similar. Our method includes concentration of the bacteria before DNA-extraction. This may account for the maintenance of diagnostic sensitivity. Diagnostic sensitivity in the real-time PCR assays of the pooled samples were comparable to the sensitivity obtained for individually analysed samples. Even sub-clinical infections were able to be detected in the pooled PCR samples which is important for control of the disease. This method may therefore be implemented in footrot control programs where it can replace analysis of individual samples.

Creativity as a Key Driver for Designing Context Sensitive Health Informatics.

PubMed

Zhou, Chunfang; Nøhr, Christian

2017-01-01

In order to face the increasing challenges of complexity and uncertainty in practice of health care, this paper aims to discuss how creativity can contribute to design new technologies in health informatics systems. It will firstly introduce the background highlighting creativity as a missing element in recent studies on context sensitive health informatics. Secondly, the concept of creativity and its relationship with activities of technology design will be discussed from a socio-culture perspective. This will be thirdly followed by understanding the roles of creativity in designing new health informatics technologies for meeting needs of high context sensitivity. Finally, a series of potential strategies will be suggested to improve creativity among technology designers working in healthcare industries. Briefly, this paper innovatively bridges two areas studies on creativity and context sensitive health informatics by issues of technology design that also indicates its important significances for future research.

Real-Time GNSS Positioning with JPL's new GIPSYx Software

NASA Astrophysics Data System (ADS)

Bar-Sever, Y. E.

2016-12-01

The JPL Global Differential GPS (GDGPS) System is now producing real-time orbit and clock solutions for GPS, GLONASS, BeiDou, and Galileo. The operations are based on JPL's next generation geodetic analysis and data processing software, GIPSYx (also known at RTGx). We will examine the impact of the nascent GNSS constellations on real-time kinematic positioning for earthquake monitoring, and assess the marginal benefits from each constellation. We will discus the options for signal selection, inter-signal bias modeling, and estimation strategies in the context of real-time point positioning. We will provide a brief overview of the key features and attributes of GIPSYx. Finally we will describe the current natural hazard monitoring services from the GDGPS System.

Stimulus appraisal modulates cardiac reactivity to briefly presented mutilation pictures.

PubMed

Mocaiber, Izabela; Perakakis, Pandelis; Pereira, Mirtes Garcia; Pinheiro, Walter Machado; Volchan, Eliane; de Oliveira, Letícia; Vila, Jaime

2011-09-01

Emotional reactions to threatening situations can be either advantageous for human adaptation or unfavorable for physical and mental health if sustained over prolonged periods of time. These contrasting effects mostly depend on the individual's capacity for emotion regulation. It has been shown, for example, that changing appraisal can alter the course of emotional processing. In the present study, the influence of stimulus appraisal over cardiac reactivity to briefly presented (200ms) mutilation pictures was tested in the context of an affective classification task. Heart rate and reaction time of twenty-four undergraduate students were monitored during the presentation of pictures (neutral or mutilated bodies) in successive blocks. In one condition (real), participants were told that the pictures depicted real events. In the other condition (fictitious), they were told that the pictures were taken from movie scenes. As expected, the results showed a more pronounced bradycardia to mutilation pictures, in comparison to neural pictures, in the real context. In the fictitious context, a significant attenuation of the emotional modulation (defensive bradycardia) was observed. However, this attenuation seemed to be transient because it was only observed in the first presentation block of the fictitious context. Reaction time to classify mutilation pictures, compared to neutral pictures, was slower in both contexts, reflecting the privileged processing of emotionally laden material. The present findings show that even briefly presented mutilation pictures elicit a differential cardiac reactivity and modulate behavioral performance. Importantly, changing stimulus appraisal attenuates the emotional modulation of cardiac reactivity (defensive bradycardia). Copyright © 2011 Elsevier B.V. All rights reserved.

Toroidal sensor arrays for real-time photoacoustic imaging

NASA Astrophysics Data System (ADS)

Bychkov, Anton S.; Cherepetskaya, Elena B.; Karabutov, Alexander A.; Makarov, Vladimir A.

2017-07-01

This article addresses theoretical and numerical investigation of image formation in photoacoustic (PA) imaging with complex-shaped concave sensor arrays. The spatial resolution and the size of sensitivity region of PA and laser ultrasonic (LU) imaging systems are assessed using sensitivity maps and spatial resolution maps in the image plane. This paper also discusses the relationship between the size of high-sensitivity regions and the spatial resolution of real-time imaging systems utilizing toroidal arrays. It is shown that the use of arrays with toroidal geometry significantly improves the diagnostic capabilities of PA and LU imaging to investigate biological objects, rocks, and composite materials.

Design of a portable imager for near-infrared visualization of cutaneous wounds

PubMed Central

Peng, Zhaoqiang; Zhou, Jun; Dacy, Ashley; Zhao, Deyin; Kearney, Vasant; Zhou, Weidong; Tang, Liping; Hu, Wenjing

2017-01-01

Abstract. A portable imager developed for real-time imaging of cutaneous wounds in research settings is described. The imager consists of a high-resolution near-infrared CCD camera capable of detecting both bioluminescence and fluorescence illuminated by an LED ring with a rotatable filter wheel. All external components are integrated into a compact camera attachment. The device is demonstrated to have competitive performance with a commercial animal imaging enclosure box setup in beam uniformity and sensitivity. Specifically, the device was used to visualize the bioluminescence associated with increased reactive oxygen species activity during the wound healing process in a cutaneous wound inflammation model. In addition, this device was employed to observe the fluorescence associated with the activity of matrix metalloproteinases in a mouse lipopolysaccharide-induced infection model. Our results support the use of the portable imager design as a noninvasive and real-time imaging tool to assess the extent of wound inflammation and infection. PMID:28114448

Spatiotemporal control of opioid signaling and behavior

PubMed Central

Siuda, Edward R.; Copits, Bryan A.; Schmidt, Martin J.; Baird, Madison A.; Al-Hasani, Ream; Planer, William J.; Funderburk, Samuel C.; McCall, Jordan G.; Gereau, Robert W.; Bruchas, Michael R.

2015-01-01

Summary Optogenetics is now a widely accepted tool for spatiotemporal manipulation of neuronal activity. However, a majority of optogenetic approaches use binary on/off control schemes. Here we extend the optogenetic toolset by developing a neuromodulatory approach using a rationale-based design to generate a Gi-coupled, optically-sensitive, mu-opioid-like receptor, we term opto-MOR. We demonstrate that opto-MOR engages canonical mu-opioid signaling through inhibition of adenylyl cyclase, activation of MAPK and G protein-gated inward rectifying potassium (GIRK) channels, and internalizes with similar kinetics as the mu-opioid receptor. To assess in vivo utility we expressed a Cre-dependent viral opto-MOR in RMTg/VTA GABAergic neurons, which led to a real-time place preference. In contrast, expression of opto-MOR in GABAergic neurons of the ventral pallidum hedonic cold spot, led to real-time place aversion. This tool has generalizable application for spatiotemporal control of opioid signaling and, furthermore, can be used broadly for mimicking endogenous neuronal inhibition pathways. PMID:25937173

Bat white-nose syndrome: a real-time TaqMan polymerase chain reaction test targeting the intergenic spacer region of Geomyces destructanstructans.

USGS Publications Warehouse

Muller, Laura K.; Lorch, Jeffrey M.; Lindner, Daniel L.; O'Connor, Michael; Gargas, Andrea; Blehert, David S.

2013-01-01

The fungus Geomyces destructans is the causative agent of white-nose syndrome (WNS), a disease that has killed millions of North American hibernating bats. We describe a real-time TaqMan PCR test that detects DNA from G. destructans by targeting a portion of the multicopy intergenic spacer region of the rRNA gene complex. The test is highly sensitive, consistently detecting as little as 3.3 fg of genomic DNA from G. destructans. The real-time PCR test specifically amplified genomic DNA from G. destructans but did not amplify target sequence from 54 closely related fungal isolates (including 43 Geomyces spp. isolates) associated with bats. The test was further qualified by analyzing DNA extracted from 91 bat wing skin samples, and PCR results matched histopathology findings. These data indicate the real-time TaqMan PCR method described herein is a sensitive, specific, and rapid test to detect DNA from G. destructans and provides a valuable tool for WNS diagnostics and research.

Developing Management Student Cultural Fluency for the Real World: A Situated Cultural Learning Approach

ERIC Educational Resources Information Center

Zhu, Yunxia; Okimoto, Tyler G.; Roan, Amanda; Xu, Henry

2017-01-01

Purpose: To connect students with the real world of management practice, the purpose of this paper is to extend and operationalize the situated cultural learning approach (SiCuLA) through five learning processes occurring within communities of practice. These include integration of cultural contexts, authentic activities, reflections,…

21st-Century Urban Renewal: Mathematical Understanding of Real-World Graphical Data Using Geospatial Technologies

ERIC Educational Resources Information Center

DeBay, Dennis J.

2017-01-01

The introduction of real-world, meaningful tasks in mathematics classrooms promises to create opportunities for enhancing students' learning through active engagement with mathematical ideas; however, researchers have given little consideration to the contexts in which urban high-school students live. The case study of three students reported in…

High sensitive reflection type long period fiber grating biosensor for real time detection of thyroglobulin, a differentiated thyroid cancer biomarker: the Smart Health project

NASA Astrophysics Data System (ADS)

Quero, G.; Severino, R.; Vaiano, P.; Consales, M.; Ruvo, M.; Sandomenico, A.; Borriello, A.; Giordano, M.; Zuppolini, S.; Diodato, L.; Cutolo, A.; Cusano, A.

2015-09-01

We report the development of a reflection-type long period fiber grating (LPG) biosensor able to perform the real time detection of thyroid cancer markers in the needle washout of fine-needle aspiration biopsy. A standard LPG is first transformed in a practical probe working in reflection mode, then it is coated by an atactic-polystyrene overlay in order to increase its surrounding refractive index sensitivity and to provide, at the same time, the desired interfacial properties for a stable bioreceptor immobilization. The results provide a clear demonstration of the effectiveness and sensitivity of the developed biosensing platform, allowing the in vitro detection of human Thyroglobulin at sub-nanomolar concentrations.

Quantitative detection of the potato cyst nematode, Globodera pallida, and the beet cyst nematode, Heterodera schachtii, using Real-Time PCR with SYBR green I dye.

PubMed

Madani, Mehrdad; Subbotin, Sergei A; Moens, Maurice

2005-04-01

The potato cyst nematode Globodera pallida and the beet cyst nematode Heterodera schachtii are major nematode pests in world agriculture. Precise identification and knowledge about the number of nematodes in field soil are necessary to develop effective integrated pest control. Here we report the results of the Real-Time PCR assay for the rapid detection and quantification of G. pallida and H. schachtii. Using species specific primers and SYBR green I dye, we were able to detect a single second stage juvenile of cyst forming nematodes in samples. The specificity of the reaction was confirmed by the lack of amplification of DNAs from other Heterodera or Globodera species. Validation tests showed a rather high correlation between real numbers of second stage juveniles in a sample and expected numbers detected by Real-Time PCR. Reasons for observed differences in sensitivity and reliability of quantification detection for two species as well as other problems of Real-Time PCR are discussed. The Real-Time PCR assay with SYBR green I dye targeting fragments of the ITS-rDNA provided a sensitive means for the rapid and simultaneous detection and quantification of juveniles of these pests.

The Feedback-Related Negativity and the P300 Brain Potential Are Sensitive to Price Expectation Violations in a Virtual Shopping Task.

PubMed

Schaefer, Alexandre; Buratto, Luciano G; Goto, Nobuhiko; Brotherhood, Emilie V

A large body of evidence shows that buying behaviour is strongly determined by consumers' price expectations and the extent to which real prices violate these expectations. Despite the importance of this phenomenon, little is known regarding its neural mechanisms. Here we show that two patterns of electrical brain activity known to index prediction errors-the Feedback-Related Negativity (FRN) and the feedback-related P300 -were sensitive to price offers that were cheaper than participants' expectations. In addition, we also found that FRN amplitude time-locked to price offers predicted whether a product would be subsequently purchased or not, and further analyses suggest that this result was driven by the sensitivity of the FRN to positive price expectation violations. This finding strongly suggests that ensembles of neurons coding positive prediction errors play a critical role in real-life consumer behaviour. Further, these findings indicate that theoretical models based on the notion of prediction error, such as the Reinforcement Learning Theory, can provide a neurobiologically grounded account of consumer behavior.

The Feedback-Related Negativity and the P300 Brain Potential Are Sensitive to Price Expectation Violations in a Virtual Shopping Task

PubMed Central

Schaefer, Alexandre; Buratto, Luciano G.; Goto, Nobuhiko; Brotherhood, Emilie V.

2016-01-01

A large body of evidence shows that buying behaviour is strongly determined by consumers’ price expectations and the extent to which real prices violate these expectations. Despite the importance of this phenomenon, little is known regarding its neural mechanisms. Here we show that two patterns of electrical brain activity known to index prediction errors–the Feedback-Related Negativity (FRN) and the feedback-related P300 –were sensitive to price offers that were cheaper than participants’ expectations. In addition, we also found that FRN amplitude time-locked to price offers predicted whether a product would be subsequently purchased or not, and further analyses suggest that this result was driven by the sensitivity of the FRN to positive price expectation violations. This finding strongly suggests that ensembles of neurons coding positive prediction errors play a critical role in real-life consumer behaviour. Further, these findings indicate that theoretical models based on the notion of prediction error, such as the Reinforcement Learning Theory, can provide a neurobiologically grounded account of consumer behavior. PMID:27658301

Automated Urban Travel Interpretation: A Bottom-up Approach for Trajectory Segmentation.

PubMed

Das, Rahul Deb; Winter, Stephan

2016-11-23

Understanding travel behavior is critical for an effective urban planning as well as for enabling various context-aware service provisions to support mobility as a service (MaaS). Both applications rely on the sensor traces generated by travellers' smartphones. These traces can be used to interpret travel modes, both for generating automated travel diaries as well as for real-time travel mode detection. Current approaches segment a trajectory by certain criteria, e.g., drop in speed. However, these criteria are heuristic, and, thus, existing approaches are subjective and involve significant vagueness and uncertainty in activity transitions in space and time. Also, segmentation approaches are not suited for real time interpretation of open-ended segments, and cannot cope with the frequent gaps in the location traces. In order to address all these challenges a novel, state based bottom-up approach is proposed. This approach assumes a fixed atomic segment of a homogeneous state, instead of an event-based segment, and a progressive iteration until a new state is found. The research investigates how an atomic state-based approach can be developed in such a way that can work in real time, near-real time and offline mode and in different environmental conditions with their varying quality of sensor traces. The results show the proposed bottom-up model outperforms the existing event-based segmentation models in terms of adaptivity, flexibility, accuracy and richness in information delivery pertinent to automated travel behavior interpretation.

Automated Urban Travel Interpretation: A Bottom-up Approach for Trajectory Segmentation

PubMed Central

Das, Rahul Deb; Winter, Stephan

2016-01-01

Understanding travel behavior is critical for an effective urban planning as well as for enabling various context-aware service provisions to support mobility as a service (MaaS). Both applications rely on the sensor traces generated by travellers’ smartphones. These traces can be used to interpret travel modes, both for generating automated travel diaries as well as for real-time travel mode detection. Current approaches segment a trajectory by certain criteria, e.g., drop in speed. However, these criteria are heuristic, and, thus, existing approaches are subjective and involve significant vagueness and uncertainty in activity transitions in space and time. Also, segmentation approaches are not suited for real time interpretation of open-ended segments, and cannot cope with the frequent gaps in the location traces. In order to address all these challenges a novel, state based bottom-up approach is proposed. This approach assumes a fixed atomic segment of a homogeneous state, instead of an event-based segment, and a progressive iteration until a new state is found. The research investigates how an atomic state-based approach can be developed in such a way that can work in real time, near-real time and offline mode and in different environmental conditions with their varying quality of sensor traces. The results show the proposed bottom-up model outperforms the existing event-based segmentation models in terms of adaptivity, flexibility, accuracy and richness in information delivery pertinent to automated travel behavior interpretation. PMID:27886053

Reward and punishment learning in daily life: A replication study

PubMed Central

van Roekel, Eeske; Wichers, Marieke; Oldehinkel, Albertine J.

2017-01-01

Day-to-day experiences are accompanied by feelings of Positive Affect (PA) and Negative Affect (NA). Implicitly, without conscious processing, individuals learn about the reward and punishment value of each context and activity. These associative learning processes, in turn, affect the probability that individuals will re-engage in such activities or seek out that context. So far, implicit learning processes are almost exclusively investigated in controlled laboratory settings and not in daily life. Here we aimed to replicate the first study that investigated implicit learning processes in real life, by means of the Experience Sampling Method (ESM). That is, using an experience-sampling study with 90 time points (three measurements over 30 days), we prospectively measured time spent in social company and amount of physical activity as well as PA and NA in the daily lives of 18-24-year-old young adults (n = 69 with anhedonia, n = 69 without anhedonia). Multilevel analyses showed a punishment learning effect with regard to time spent in company of friends, but not a reward learning effect. Neither reward nor punishment learning effects were found with regard to physical activity. Our study shows promising results for future research on implicit learning processes in daily life, with the proviso of careful consideration of the timescale used. Short-term retrospective ESM design with beeps approximately six hours apart may suffer from mismatch noise that hampers accurate detection of associative learning effects over time. PMID:28976985

Real-Time linux dynamic clamp: a fast and flexible way to construct virtual ion channels in living cells.

PubMed

Dorval, A D; Christini, D J; White, J A

2001-10-01

We describe a system for real-time control of biological and other experiments. This device, based around the Real-Time Linux operating system, was tested specifically in the context of dynamic clamping, a demanding real-time task in which a computational system mimics the effects of nonlinear membrane conductances in living cells. The system is fast enough to represent dozens of nonlinear conductances in real time at clock rates well above 10 kHz. Conductances can be represented in deterministic form, or more accurately as discrete collections of stochastically gating ion channels. Tests were performed using a variety of complex models of nonlinear membrane mechanisms in excitable cells, including simulations of spatially extended excitable structures, and multiple interacting cells. Only in extreme cases does the computational load interfere with high-speed "hard" real-time processing (i.e., real-time processing that never falters). Freely available on the worldwide web, this experimental control system combines good performance. immense flexibility, low cost, and reasonable ease of use. It is easily adapted to any task involving real-time control, and excels in particular for applications requiring complex control algorithms that must operate at speeds over 1 kHz.

Whispering gallery mode sensors

PubMed Central

Foreman, Matthew R.; Swaim, Jon D.; Vollmer, Frank

2015-01-01

We present a comprehensive overview of sensor technology exploiting optical whispering gallery mode (WGM) resonances. After a short introduction we begin by detailing the fundamental principles and theory of WGMs in optical microcavities and the transduction mechanisms frequently employed for sensing purposes. Key recent theoretical contributions to the modeling and analysis of WGM systems are highlighted. Subsequently we review the state of the art of WGM sensors by outlining efforts made to date to improve current detection limits. Proposals in this vein are numerous and range, for example, from plasmonic enhancements and active cavities to hybrid optomechanical sensors, which are already working in the shot noise limited regime. In parallel to furthering WGM sensitivity, efforts to improve the time resolution are beginning to emerge. We therefore summarize the techniques being pursued in this vein. Ultimately WGM sensors aim for real-world applications, such as measurements of force and temperature, or alternatively gas and biosensing. Each such application is thus reviewed in turn, and important achievements are discussed. Finally, we adopt a more forward-looking perspective and discuss the outlook of WGM sensors within both a physical and biological context and consider how they may yet push the detection envelope further. PMID:26973759

The Deep Lens Survey : Real--time Optical Transient and Moving Object Detection

NASA Astrophysics Data System (ADS)

Becker, Andy; Wittman, David; Stubbs, Chris; Dell'Antonio, Ian; Loomba, Dinesh; Schommer, Robert; Tyson, J. Anthony; Margoniner, Vera; DLS Collaboration

2001-12-01

We report on the real-time optical transient program of the Deep Lens Survey (DLS). Meeting the DLS core science weak-lensing objective requires repeated visits to the same part of the sky, 20 visits for 63 sub-fields in 4 filters, on a 4-m telescope. These data are reduced in real-time, and differenced against each other on all available timescales. Our observing strategy is optimized to allow sensitivity to transients on several minute, one day, one month, and one year timescales. The depth of the survey allows us to detect and classify both moving and stationary transients down to ~ 25th magnitude, a relatively unconstrained region of astronomical variability space. All transients and moving objects, including asteroids, Kuiper belt (or trans-Neptunian) objects, variable stars, supernovae, 'unknown' bursts with no apparent host, orphan gamma-ray burst afterglows, as well as airplanes, are posted on the web in real-time for use by the community. We emphasize our sensitivity to detect and respond in real-time to orphan afterglows of gamma-ray bursts, and present one candidate orphan in the field of Abell 1836. See http://dls.bell-labs.com/transients.html.

A Context Awareness System for Online Learning: Design Based Research

ERIC Educational Resources Information Center

Laffey, James; Amelung, Chris; Goggins, Sean

2009-01-01

A design based research strategy examining the impressions and behavior of members of courses taught entirely online is used for refining a context-aware activity notification system (CANS). The findings show that CANS must address substantial variety in courses and members while also fitting with multitasking between online and real world…

First-Year Students' Beliefs about Context Problems in Mathematics in University Science Programmes

ERIC Educational Resources Information Center

Drobnic Vidic, Andreja

2015-01-01

Mathematics-related beliefs play an important role in the willingness to engage in academic activities in mathematics education. Such beliefs might not be consistent with the beliefs students hold about context problems that require sufficient mathematical knowledge and the application of such knowledge to various real-life situations. This study…

Mechanistic basis of temperature-dependent dwell fatigue in titanium alloys

NASA Astrophysics Data System (ADS)

Zheng, Zebang; Balint, Daniel S.; Dunne, Fionn P. E.

2017-10-01

The temperature-dependent dwell sensitivity of Ti-6242 and Ti-6246 alloys has been assessed over a temperature range from - 50∘ C to 390 °C using discrete dislocation plasticity which incorporates both thermal activation of dislocation escape from obstacles and slip transfer across grain boundaries. The worst-case load shedding in Ti-6242 alloy is found to be at or close to 120 °C under dwell fatigue loading, which diminishes and vanishes at temperatures lower than - 50∘ C or higher than 230 °C. Load shedding behaviour is predicted to occur in alloy Ti-6246 also but over a range of higher temperatures which are outside those relevant to in-service conditions. The key controlling dislocation mechanism with respect to load shedding in titanium alloys, and its temperature sensitivity, is shown to be the time constant associated with the thermal activation of dislocation escape from obstacles, with respect to the stress dwell time. The mechanistic basis of load shedding and dwell sensitivity in dwell fatigue loading is presented and discussed in the context of experimental observations.

Variable Omission of "ne" in Real-Time French Chat: A Corpus-Driven Comparison of Educational and Non-Educational Contexts

ERIC Educational Resources Information Center

van Compernolle, Remi A.; Williams, Lawrence

2009-01-01

This article reports on the variable omission of the French negative particle "ne" (the first marker of verbal negation) in synchronous (i.e., real-time) electronic communication environments. Patterns of variation in a corpus of non-educational chat (i.e., free, public-access Internet chat) are analyzed and compared to data produced by first-,…

Comparison of real-time PCR methods for the detection of Naegleria fowleri in surface water and sediment.

PubMed

Streby, Ashleigh; Mull, Bonnie J; Levy, Karen; Hill, Vincent R

2015-05-01

Naegleria fowleri is a thermophilic free-living ameba found in freshwater environments worldwide. It is the cause of a rare but potentially fatal disease in humans known as primary amebic meningoencephalitis. Established N. fowleri detection methods rely on conventional culture techniques and morphological examination followed by molecular testing. Multiple alternative real-time PCR assays have been published for rapid detection of Naegleria spp. and N. fowleri. Foursuch assays were evaluated for the detection of N. fowleri from surface water and sediment. The assays were compared for thermodynamic stability, analytical sensitivity and specificity, detection limits, humic acid inhibition effects, and performance with seeded environmental matrices. Twenty-one ameba isolates were included in the DNA panel used for analytical sensitivity and specificity analyses. N. fowleri genotypes I and III were used for method performance testing. Two of the real-time PCR assays were determined to yield similar performance data for specificity and sensitivity for detecting N. fowleri in environmental matrices.

Comparison of real-time PCR methods for the detection of Naegleria fowleri in surface water and sediment

PubMed Central

Streby, Ashleigh; Mull, Bonnie J.; Levy, Karen

2015-01-01

Naegleria fowleri is a thermophilic free-living ameba found in freshwater environments worldwide. It is the cause of a rare but potentially fatal disease in humans known as primary amebic meningoencephalitis. Established N. fowleri detection methods rely on conventional culture techniques and morphological examination followed by molecular testing. Multiple alternative real-time PCR assays have been published for rapid detection of Naegleria spp. and N. fowleri. Four such assays were evaluated for the detection of N. fowleri from surface water and sediment. The assays were compared for thermodynamic stability, analytical sensitivity and specificity, detection limits, humic acid inhibition effects, and performance with seeded environmental matrices. Twenty-one ameba isolates were included in the DNA panel used for analytical sensitivity and specificity analyses. N. fowleri genotypes I and III were used for method performance testing. Two of the real-time PCR assays were determined to yield similar performance data for specificity and sensitivity for detecting N. fowleri in environmental matrices. PMID:25855343

Evaluation of two real time PCR assays for the detection of bacterial DNA in amniotic fluid.

PubMed

Girón de Velasco-Sada, Patricia; Falces-Romero, Iker; Quiles-Melero, Inmaculada; García-Perea, Adela; Mingorance, Jesús

2018-01-01

The aim of this study was to evaluate two non-commercial Real-Time PCR assays for the detection of microorganisms in amniotic fluid followed by identification by pyrosequencing. We collected 126 amniotic fluids from 2010 to 2015 for the evaluation of two Real-Time PCR assays for detection of bacterial DNA in amniotic fluid (16S Universal PCR and Ureaplasma spp. specific PCR). The method was developed in the Department of Microbiology of the University Hospital La Paz. Thirty-seven samples (29.3%) were positive by PCR/pyrosequencing and/or culture, 4 of them were mixed cultures with Ureaplasma urealyticum. The Universal 16S Real-Time PCR was compared with the standard culture (81.8% sensitivity, 97.4% specificity, 75% positive predictive value, 98% negative predictive value). The Ureaplasma spp. specific Real-Time PCR was compared with the Ureaplasma/Mycoplasma specific culture (92.3% sensitivity, 89.4% specificity, 50% positive predictive value, 99% negative predictive value) with statistically significant difference (p=0.005). Ureaplasma spp. PCR shows a rapid response time (5h from DNA extraction until pyrosequencing) when comparing with culture (48h). So, the response time of bacteriological diagnosis in suspected chorioamnionitis is reduced. Copyright © 2017 Elsevier B.V. All rights reserved.

Activating Event Knowledge

ERIC Educational Resources Information Center

Hare, Mary; Jones, Michael; Thomson, Caroline; Kelly, Sarah; McRae, Ken

2009-01-01

An increasing number of results in sentence and discourse processing demonstrate that comprehension relies on rich pragmatic knowledge about real-world events, and that incoming words incrementally activate such knowledge. If so, then even outside of any larger context, nouns should activate knowledge of the generalized events that they denote or…

Aging in Activity Space: Results From Smartphone-Based GPS-Tracking of Urban Seniors.

PubMed

York Cornwell, Erin; Cagney, Kathleen A

2017-09-01

Prior research emphasizes the importance of the residential neighborhood context during later life but little attention has been afforded to other areas that older adults encounter as they move beyond their residential environments for daily activities and social interactions. This study examines the predominance of the residential context within older adults' everyday lives. We provided 60 older adults in four New York City neighborhoods with iPhones, which captured Global Positioning Systems (GPS) locations at 5-min intervals over 1 week (n = 55,561) and 17 ecological momentary assessments (EMAs) over 4 days (n = 757) to assess real-time activities. Older adults in our sample spent nearly 40% of their time outside of their residential tracts and they visited 28 other tracts, on average. Exercising, shopping, socializing, and social activities were especially likely to take place outside of residential tracts. Differences in residential and nonresidential poverty exposure vary across gender, race/ethnicity, education, car ownership, and residential areas. Measuring activity space, rather than relying on residential tracts, allows examination of the social environments that are relevant for older adults' everyday lives. Variation in characteristics of activity spaces may be an underexplored source of differences in health and well-being during later life. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A Context-Aware Method for Authentically Simulating Outdoors Shadows for Mobile Augmented Reality.

PubMed

Barreira, Joao; Bessa, Maximino; Barbosa, Luis; Magalhaes, Luis

2018-03-01

Visual coherence between virtual and real objects is a major issue in creating convincing augmented reality (AR) applications. To achieve this seamless integration, actual light conditions must be determined in real time to ensure that virtual objects are correctly illuminated and cast consistent shadows. In this paper, we propose a novel method to estimate daylight illumination and use this information in outdoor AR applications to render virtual objects with coherent shadows. The illumination parameters are acquired in real time from context-aware live sensor data. The method works under unprepared natural conditions. We also present a novel and rapid implementation of a state-of-the-art skylight model, from which the illumination parameters are derived. The Sun's position is calculated based on the user location and time of day, with the relative rotational differences estimated from a gyroscope, compass and accelerometer. The results illustrated that our method can generate visually credible AR scenes with consistent shadows rendered from recovered illumination.

The diagnosis of microorganism involved in infective endocarditis (IE) by polymerase chain reaction (PCR) and real-time PCR: A systematic review.

PubMed

Faraji, Reza; Behjati-Ardakani, Mostafa; Moshtaghioun, Seyed Mohammad; Kalantar, Seyed Mehdi; Namayandeh, Seyedeh Mahdieh; Soltani, Mohammadhossien; Emami, Mahmood; Zandi, Hengameh; Firoozabadi, Ali Dehghani; Kazeminasab, Mahmood; Ahmadi, Nastaran; Sarebanhassanabadi, Mohammadtaghi

2018-02-01

Broad-range bacterial rDNA polymerase chain reaction (PCR) followed by sequencing may be identified as the etiology of infective endocarditis (IE) from surgically removed valve tissue; therefore, we reviewed the value of molecular testing in identifying organisms' DNA in the studies conducted until 2016. We searched Google Scholar, Scopus, ScienceDirect, Cochrane, PubMed, and Medline electronic databases without any time limitations up to December 2016 for English studies reporting microorganisms involved in infective endocarditis microbiology using PCR and real-time PCR. Most studies were prospective. Eleven out of 12 studies used valve tissue samples and blood cultures while only 1 study used whole blood. Also, 10 studies used the molecular method of PCR while 2 studies used real-time PCR. Most studies used 16S rDNA gene as the target gene. The bacteria were identified as the most common microorganisms involved in infective endocarditis. Streptococcus spp. and Staphylococcus spp. were, by far, the most predominant bacteria detected. In all studies, PCR and real-time PCR identified more pathogens than blood and tissue cultures; moreover, the sensitivity and specificity of PCR and real-time PCR were more than cultures in most of the studies. The highest sensitivity and specificity were 96% and 100%, respectively. The gram positive bacteria were the most frequent cause of infective endocarditis. The molecular methods enjoy a greater sensitivity compared to the conventional blood culture methods; yet, they are applicable only to the valve tissue of the patients undergoing cardiac valve surgery. Copyright © 2017. Published by Elsevier Taiwan.

Qualitative real-time analysis by nurses of sublingual microcirculation in intensive care unit: the MICRONURSE study.

PubMed

Tanaka, Sébastien; Harrois, Anatole; Nicolaï, Camille; Flores, Mélanie; Hamada, Sophie; Vicaut, Eric; Duranteau, Jacques

2015-11-06

We aimed to determine i) the feasibility of nurses taking bedside measurements of microcirculatory parameters in real time in intensive care patients; and ii) whether such measurements would be comparable to those obtained by the classical delayed semi quantitative analysis made by a physician. This prospective observational study was conducted in a university hospital and was approved by our local Institutional Review Board (IRB 00006477). After ICU admission and study inclusion, a set of measurements of macrocirculatory and microcirculatory parameters was taken by the nurse in charge of the patient every 4 h within the first 12 h after admission and before and after every hemodynamic therapeutic intervention. Seventy-four sublingual microvascular measurements were performed with incident dark field illumination (IDF) microscopy in 20 mechanically ventilated patients hospitalized in the ICU. There were no significant differences between the microvascular flow index (MFI) taken in real time by the nurses and the delayed evaluation by the physician. In fact, the nurses' real-time measurement of MFI demonstrated good agreement with the physician's delayed measurement. The mean difference between the two MFIs was -0.15, SD = 0.28. The nurses' real-time MFI assessment showed 97 % sensitivity (95 % CI: 84-99 %) and 95 % specificity (95 % CI: 84-99 %) at detecting a MFI <2.5 obtained by a physician upon delayed semiquantitative measurement. Concerning the density, 81 % of the paramedical qualitative density measurements corresponded with the automatized total vessel density (TVD) measurements. The nurses' real-time TVD assessment showed 77 % sensitivity (95 % CI: 46-95 %) and 100 % specificity (95 % CI: 89-100 %) at detecting a TVD <8 mm/mm(2). A real-time qualitative bedside evaluation of MFI by nurses showed good agreement with the conventional delayed analysis by physicians. The bedside evaluations of MFI and TVD were highly sensitive and specific for detecting impaired microvascular flow and low capillary density. These results suggest that this real-time technique could become part of ICU nurse routine surveillance and be implemented in algorithms for hemodynamic resuscitation in future clinical trials and regular practice. These results are an essential step to demonstrate whether these real-time measurements have a clinical impact in the management of ICU patients.

The development and validation of a Real Time Location System to reliably monitor everyday activities in natural contexts.

PubMed

Judah, Gaby; de Witt Huberts, Jessie; Drassal, Allan; Aunger, Robert

2017-01-01

The accurate measurement of behaviour is vitally important to many disciplines and practitioners of various kinds. While different methods have been used (such as observation, diaries, questionnaire), none are able to accurately monitor behaviour over the long term in the natural context of people's own lives. The aim of this work was therefore to develop and test a reliable system for unobtrusively monitoring various behaviours of multiple individuals within the same household over a period of several months. A commercial Real Time Location System was adapted to meet these requirements and subsequently validated in three households by monitoring various bathroom behaviours. The results indicate that the system is robust, can monitor behaviours over the long-term in different households and can reliably distinguish between individuals. Precision rates were high and consistent. Recall rates were less consistent across households and behaviours, although recall rates improved considerably with practice at set-up of the system. The achieved precision and recall rates were comparable to the rates observed in more controlled environments using more valid methods of ground truthing. These initial findings indicate that the system is a valuable, flexible and robust system for monitoring behaviour in its natural environment that would allow new research questions to be addressed.

On Curating Multimodal Sensory Data for Health and Wellness Platforms

PubMed Central

Amin, Muhammad Bilal; Banos, Oresti; Khan, Wajahat Ali; Muhammad Bilal, Hafiz Syed; Gong, Jinhyuk; Bui, Dinh-Mao; Cho, Soung Ho; Hussain, Shujaat; Ali, Taqdir; Akhtar, Usman; Chung, Tae Choong; Lee, Sungyoung

2016-01-01

In recent years, the focus of healthcare and wellness technologies has shown a significant shift towards personal vital signs devices. The technology has evolved from smartphone-based wellness applications to fitness bands and smartwatches. The novelty of these devices is the accumulation of activity data as their users go about their daily life routine. However, these implementations are device specific and lack the ability to incorporate multimodal data sources. Data accumulated in their usage does not offer rich contextual information that is adequate for providing a holistic view of a user’s lifelog. As a result, making decisions and generating recommendations based on this data are single dimensional. In this paper, we present our Data Curation Framework (DCF) which is device independent and accumulates a user’s sensory data from multimodal data sources in real time. DCF curates the context of this accumulated data over the user’s lifelog. DCF provides rule-based anomaly detection over this context-rich lifelog in real time. To provide computation and persistence over the large volume of sensory data, DCF utilizes the distributed and ubiquitous environment of the cloud platform. DCF has been evaluated for its performance, correctness, ability to detect complex anomalies, and management support for a large volume of sensory data. PMID:27355955

The Role of Habits in Massive Multiplayer Online Role-Playing Game Usage: Predicting Excessive and Problematic Gaming Through Players' Sensitivity to Situational Cues.

PubMed

Lukavská, Kateřina; Hrabec, Ondřej; Chrz, Vladimír

2016-04-01

We examined the effect of habitual regulation of massive multiplayer online role-playing game (MMORPG) playing on the problematic (addictive) usage and excessiveness of gaming (time that user spent playing weekly, per session, and in relation to his other leisure activities). We developed the approach to assess the strength of habitual regulation that was based on sensitivity to situational cues. We defined cues as real-life or in-game conditions (e.g., work to be done, activities with friends or family, need to relax, new game expansion) that usually promote gaming (proplay cues) or prevent it (contraplay cues). Using a sample of 377 MMORPG players, we analyzed relationships between variables through partial least squares path modeling. We found that proplay cues sensitivity significantly positively affected the excessiveness of gaming (playing time) as well as the occurrence of problematic usage symptoms. Conversely, contraplay cues sensitivity functioned as a protective factor from these conditions; significant negative effects were found for playing time and problematic usage. Playing time was confirmed to be a mediating variable, affected by cues sensitivity and at the same time affecting problematic usage symptoms. We obtained moderately strong coefficients of determination for both endogenous variables (R(2) = 0.28 for playing time; R(2) = 0.31 for problematic usage) suggesting that the proposed variables possess good explanatory power. Based on our results, we argue that the strength of habitual regulation within MMORPG usage has both positive and negative effects on excessive and problematic usage, which is a new and important finding within the area of Internet gaming addiction.

Beyond where to how: a machine learning approach for sensing mobility contexts using smartphone sensors.

PubMed

Guinness, Robert E

2015-04-28

This paper presents the results of research on the use of smartphone sensors (namely, GPS and accelerometers), geospatial information (points of interest, such as bus stops and train stations) and machine learning (ML) to sense mobility contexts. Our goal is to develop techniques to continuously and automatically detect a smartphone user's mobility activities, including walking, running, driving and using a bus or train, in real-time or near-real-time (<5 s). We investigated a wide range of supervised learning techniques for classification, including decision trees (DT), support vector machines (SVM), naive Bayes classifiers (NB), Bayesian networks (BN), logistic regression (LR), artificial neural networks (ANN) and several instance-based classifiers (KStar, LWLand IBk). Applying ten-fold cross-validation, the best performers in terms of correct classification rate (i.e., recall) were DT (96.5%), BN (90.9%), LWL (95.5%) and KStar (95.6%). In particular, the DT-algorithm RandomForest exhibited the best overall performance. After a feature selection process for a subset of algorithms, the performance was improved slightly. Furthermore, after tuning the parameters of RandomForest, performance improved to above 97.5%. Lastly, we measured the computational complexity of the classifiers, in terms of central processing unit (CPU) time needed for classification, to provide a rough comparison between the algorithms in terms of battery usage requirements. As a result, the classifiers can be ranked from lowest to highest complexity (i.e., computational cost) as follows: SVM, ANN, LR, BN, DT, NB, IBk, LWL and KStar. The instance-based classifiers take considerably more computational time than the non-instance-based classifiers, whereas the slowest non-instance-based classifier (NB) required about five-times the amount of CPU time as the fastest classifier (SVM). The above results suggest that DT algorithms are excellent candidates for detecting mobility contexts in smartphones, both in terms of performance and computational complexity.

Beyond Where to How: A Machine Learning Approach for Sensing Mobility Contexts Using Smartphone Sensors †

PubMed Central

Guinness, Robert E.

2015-01-01

This paper presents the results of research on the use of smartphone sensors (namely, GPS and accelerometers), geospatial information (points of interest, such as bus stops and train stations) and machine learning (ML) to sense mobility contexts. Our goal is to develop techniques to continuously and automatically detect a smartphone user's mobility activities, including walking, running, driving and using a bus or train, in real-time or near-real-time (<5 s). We investigated a wide range of supervised learning techniques for classification, including decision trees (DT), support vector machines (SVM), naive Bayes classifiers (NB), Bayesian networks (BN), logistic regression (LR), artificial neural networks (ANN) and several instance-based classifiers (KStar, LWLand IBk). Applying ten-fold cross-validation, the best performers in terms of correct classification rate (i.e., recall) were DT (96.5%), BN (90.9%), LWL (95.5%) and KStar (95.6%). In particular, the DT-algorithm RandomForest exhibited the best overall performance. After a feature selection process for a subset of algorithms, the performance was improved slightly. Furthermore, after tuning the parameters of RandomForest, performance improved to above 97.5%. Lastly, we measured the computational complexity of the classifiers, in terms of central processing unit (CPU) time needed for classification, to provide a rough comparison between the algorithms in terms of battery usage requirements. As a result, the classifiers can be ranked from lowest to highest complexity (i.e., computational cost) as follows: SVM, ANN, LR, BN, DT, NB, IBk, LWL and KStar. The instance-based classifiers take considerably more computational time than the non-instance-based classifiers, whereas the slowest non-instance-based classifier (NB) required about five-times the amount of CPU time as the fastest classifier (SVM). The above results suggest that DT algorithms are excellent candidates for detecting mobility contexts in smartphones, both in terms of performance and computational complexity. PMID:25928060

Evaluation of RealStar Reverse Transcription–Polymerase Chain Reaction Kits for Filovirus Detection in the Laboratory and Field

PubMed Central

Rieger, Toni; Kerber, Romy; El Halas, Hussein; Pallasch, Elisa; Duraffour, Sophie; Günther, Stephan; Ölschläger, Stephan

2016-01-01

Background. Diagnosis of Ebola virus (EBOV) disease (EVD) requires laboratory testing. Methods. The RealStar Filovirus Screen reverse transcription–polymerase chain reaction (RT-PCR) kit and the derived RealStar Zaire Ebolavirus RT-PCR kit were validated using in vitro transcripts, supernatant of infected cell cultures, and clinical specimens from patients with EVD. Results. The Filovirus Screen kit detected EBOV, Sudan virus, Taï Forest virus, Bundibugyo virus, Reston virus, and Marburg virus and differentiated between the genera Ebolavirus and Marburgvirus. The amount of filovirus RNA that could be detected with a probability of 95% ranged from 11 to 67 RNA copies/reaction on a LightCycler 480 II. The Zaire Ebolavirus kit is based on the Filovirus Screen kit but was optimized for detection of EBOV. It has an improved signal-to-noise ratio at low EBOV RNA concentrations and is somewhat more sensitive than the Filovirus kit. Both kits show significantly lower analytical sensitivity on a SmartCycler II. Clinical evaluation revealed that the SmartCycler II, compared with other real-time PCR platforms, decreases the clinical sensitivity of the Filovirus Screen kit to diagnose EVD at an early stage. Conclusions. The Filovirus Screen kit detects all human-pathogenic filoviruses with good analytical sensitivity if performed on an appropriate real-time PCR platform. High analytical sensitivity is important for early diagnosis of EVD. PMID:27549586

Evaluation of Two Lyophilized Molecular Assays to Rapidly Detect Foot-and-Mouth Disease Virus Directly from Clinical Samples in Field Settings.

PubMed

Howson, E L A; Armson, B; Madi, M; Kasanga, C J; Kandusi, S; Sallu, R; Chepkwony, E; Siddle, A; Martin, P; Wood, J; Mioulet, V; King, D P; Lembo, T; Cleaveland, S; Fowler, V L

2017-06-01

Accurate, timely diagnosis is essential for the control, monitoring and eradication of foot-and-mouth disease (FMD). Clinical samples from suspect cases are normally tested at reference laboratories. However, transport of samples to these centralized facilities can be a lengthy process that can impose delays on critical decision making. These concerns have motivated work to evaluate simple-to-use technologies, including molecular-based diagnostic platforms, that can be deployed closer to suspect cases of FMD. In this context, FMD virus (FMDV)-specific reverse transcription loop-mediated isothermal amplification (RT-LAMP) and real-time RT-PCR (rRT-PCR) assays, compatible with simple sample preparation methods and in situ visualization, have been developed which share equivalent analytical sensitivity with laboratory-based rRT-PCR. However, the lack of robust 'ready-to-use kits' that utilize stabilized reagents limits the deployment of these tests into field settings. To address this gap, this study describes the performance of lyophilized rRT-PCR and RT-LAMP assays to detect FMDV. Both of these assays are compatible with the use of fluorescence to monitor amplification in real-time, and for the RT-LAMP assays end point detection could also be achieved using molecular lateral flow devices. Lyophilization of reagents did not adversely affect the performance of the assays. Importantly, when these assays were deployed into challenging laboratory and field settings within East Africa they proved to be reliable in their ability to detect FMDV in a range of clinical samples from acutely infected as well as convalescent cattle. These data support the use of highly sensitive molecular assays into field settings for simple and rapid detection of FMDV. © 2015 The Authors. Transboundary and Emerging Diseases Published by Blackwell Verlag GmbH.

Real-time frequency-to-time mapping based on spectrally-discrete chromatic dispersion.

PubMed

Dai, Yitang; Li, Jilong; Zhang, Ziping; Yin, Feifei; Li, Wangzhe; Xu, Kun

2017-07-10

Traditional photonics-assisted real-time Fourier transform (RTFT) usually suffers from limited chromatic dispersion, huge volume, or large time delay and attendant loss. In this paper we propose frequency-to-time mapping (FTM) by spectrally-discrete dispersion to increase frequency sensitivity greatly. The novel media has periodic ON/OFF intensity frequency response while quadratic phase distribution along disconnected channels, which de-chirps matched optical input to repeated Fourier-transform-limited output. Real-time FTM is then obtained within each period. Since only discrete phase retardation rather than continuously-changed true time delay is required, huge equivalent dispersion is then available by compact device. Such FTM is theoretically analyzed, and implementation by cascaded optical ring resonators is proposed. After a numerical example, our theory is demonstrated by a proof-of-concept experiment, where a single loop containing 0.5-meters-long fiber is used. FTM under 400-MHz unambiguous bandwidth and 25-MHz resolution is reported. Highly-sensitive and linear mapping is achieved with 6.25 ps/MHz, equivalent to ~4.6 × 10 4 -km standard single mode fiber. Extended instantaneous bandwidth is expected by ring cascading. Our proposal may provide a promising method for real-time, low-latency Fourier transform.

Multiplexed detection of anthrax-related toxin genes.

PubMed

Moser, Michael J; Christensen, Deanna R; Norwood, David; Prudent, James R

2006-02-01

Simultaneous analysis of three targets in three colors on any real-time polymerase chain reaction (PCR) instrument would increase the flexibility of real-time PCR. For the detection of Bacillus strains that can cause inhalation anthrax-related illness, this ability would be valuable because two plasmids confer virulence, and internal positive controls are needed to monitor the testing in cases lacking target-specific signals. Using a real-time PCR platform called MultiCode-RTx, multiple assays were developed that specifically monitor the presence of Bacillus anthracis-specific virulence plasmid-associated genes. In particular for use on LightCycler-1, two triplex RTx systems demonstrated high sensitivity with limits of detection nearing single-copy levels for both plasmids. Specificity was established using a combination of Ct values and correct amplicon melting temperatures. All reactions were further verified by detection of an internal positive control. For these two triplex RTx assays, the analytical detection limit was one to nine plasmid copy equivalents, 100% analytical specificity with a 95% confidence interval (CI) of 9%, and 100% analytical sensitivity with a CI of 2%. Although further testing using clinical or environmental samples will be required to assess diagnostic sensitivity and specificity, the RTx platform achieves similar results to those of probe-based real-time systems.

A new multiplex real-time polymerase chain reaction assay for the diagnosis of periprosthetic joint infection.

PubMed

Kawamura, Masaki; Kobayashi, Naomi; Inaba, Yutaka; Choe, Hyonmin; Tezuka, Taro; Kubota, So; Saito, Tomoyuki

2017-11-01

A new multiplex real-time polymerase chain reaction (PCR) assay was developed to detect methicillin-resistant Staphylococcus (MRS) and to distinguish between gram-positive and gram-negative bacteria. In this study, we validated the sensitivity and specificity of this assay with periprosthetic joint infections (PJIs) and evaluated the utility of PCR for culture-negative PJI. Forty-five samples from 23 infectious PJI cases and 106 samples from 64 non-infectious control cases were analyzed by real-time PCR using a LightCycler Nano ® system. Twenty-eight clinical samples, comprising bacteria of known species isolated consecutively in the microbiological laboratory of our hospital, were used to determine the spectrum of bacterial species that could be detected using the new multiplex primers and probes. The sensitivity and specificity of the MRS- and universal-PCR assays were 92% and 99%, and 91% and 88%, respectively. Twenty-eight species of clinically isolated bacteria were detected using this method and the concordance rate for the identification of gram-positive or gram-negative organisms was 96%. Eight samples were identified as PCR-positive despite a culture-negative result. This novel multiplex real-time PCR system has acceptable sensitivity and specificity and several advantages; therefore, it has potential use for the diagnosis of PJIs, particularly in culture-negative cases.

Comparison of real-time PCR with disk diffusion, agar screen and E-test methods for detection of methicillin-resistant Staphylococcus aureus.

PubMed

Shariati, Laleh; Validi, Majid; Tabatabaiefar, Mohammad Amin; Karimi, Ali; Nafisi, Mohammad Reza

2010-12-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a nosocomial pathogen. Our main objective was to compare oxacillin disk test, oxacillin E-test, and oxacillin agar screen for detection of methicillin resistance in S. aureus, using real-time PCR for mecA as the "gold standard" comparison assay. 196 S. aureus isolates were identified out of 284 Staphylococcus isolates. These isolates were screened for MRSA with several methods: disk diffusion, agar screen (6.0 μg/ml), oxacillin E-test, and real-time PCR for detection of mecA gene. Of the 196 S. aureus isolates tested, 96 isolates (49%) were mecA-positive and 100 isolates (51%) mecA-negative. All methods tested had a statistically significant agreement with real-time PCR. E-test was 100% sensitive and specific for mecA presence. The sensitivity and specificity of oxacillin agar screen method were 98 and 99%, respectively and sensitivity and specificity of oxacillin disk diffusion method were 95 and 93%, respectively. In the present study, oxacillin E-test is proposed as the best phenotypic method. For economic reasons, the oxacillin agar screen method (6.0 μg/ml), which is suitable for the detection of MRSA, is recommended due to its accuracy and low cost.

Diagnosis of Cetacean morbillivirus: A sensitive one step real time RT fast-PCR method based on SYBR(®) Green.

PubMed

Sacristán, Carlos; Carballo, Matilde; Muñoz, María Jesús; Bellière, Edwige Nina; Neves, Elena; Nogal, Verónica; Esperón, Fernando

2015-12-15

Cetacean morbillivirus (CeMV) (family Paramyxoviridae, genus Morbillivirus) is considered the most pathogenic virus of cetaceans. It was first implicated in the bottlenose dolphin (Tursiops truncatus) mass stranding episode along the Northwestern Atlantic coast in the late 1980s, and in several more recent worldwide epizootics in different Odontoceti species. This study describes a new one step real-time reverse transcription fast polymerase chain reaction (real-time RT-fast PCR) method based on SYBR(®) Green to detect a fragment of the CeMV fusion protein gene. This primer set also works for conventional RT-PCR diagnosis. This method detected and identified all three well-characterized strains of CeMV: porpoise morbillivirus (PMV), dolphin morbillivirus (DMV) and pilot whale morbillivirus (PWMV). Relative sensitivity was measured by comparing the results obtained from 10-fold dilution series of PMV and DMV positive controls and a PWMV field sample, to those obtained by the previously described conventional phosphoprotein gene based RT-PCR method. Both the conventional and real-time RT-PCR methods involving the fusion protein gene were 100- to 1000-fold more sensitive than the previously described conventional RT-PCR method. Copyright © 2015 Elsevier B.V. All rights reserved.

Development of real-time and lateral flow strip reverse transcription recombinase polymerase Amplification assays for rapid detection of peste des petits ruminants virus.

PubMed

Yang, Yang; Qin, Xiaodong; Song, Yiming; Zhang, Wei; Hu, Gaowei; Dou, Yongxi; Li, Yanmin; Zhang, Zhidong

2017-02-07

Peste des petits ruminants (PPR) is an economically important, Office International des Epizooties (OIE) notifiable, transboundary viral disease of small ruminants such as sheep and goat. PPR virus (PPRV), a negative-sense single-stranded RNA virus, is the causal agent of PPR. Therefore, sensitive, specific and rapid diagnostic assay for the detection of PPRV are necessary to accurately and promptly diagnose suspected case of PPR. In this study, reverse transcription recombinase polymerase amplification assays using real-time fluorescent detection (real-time RT-RPA assay) and lateral flow strip detection (LFS RT-RPA assay) were developed targeting the N gene of PPRV. The sensitivity of the developed real-time RT-RPA assay was as low as 100 copies per reaction within 7 min at 40 °C with 95% reliability; while the sensitivity of the developed LFS RT-RPA assay was as low as 150 copies per reaction at 39 °C in less than 25 min. In both assays, there were no cross-reactions with sheep and goat pox viruses, foot-and-mouth disease virus and Orf virus. These features make RPA assay promising candidates either in field use or as a point of care diagnostic technique.

An improved optical flow tracking technique for real-time MR-guided beam therapies in moving organs

NASA Astrophysics Data System (ADS)

Zachiu, C.; Papadakis, N.; Ries, M.; Moonen, C.; de Senneville, B. Denis

2015-12-01

Magnetic resonance (MR) guided high intensity focused ultrasound and external beam radiotherapy interventions, which we shall refer to as beam therapies/interventions, are promising techniques for the non-invasive ablation of tumours in abdominal organs. However, therapeutic energy delivery in these areas becomes challenging due to the continuous displacement of the organs with respiration. Previous studies have addressed this problem by coupling high-framerate MR-imaging with a tracking technique based on the algorithm proposed by Horn and Schunck (H and S), which was chosen due to its fast convergence rate and highly parallelisable numerical scheme. Such characteristics were shown to be indispensable for the real-time guidance of beam therapies. In its original form, however, the algorithm is sensitive to local grey-level intensity variations not attributed to motion such as those that occur, for example, in the proximity of pulsating arteries. In this study, an improved motion estimation strategy which reduces the impact of such effects is proposed. Displacements are estimated through the minimisation of a variation of the H and S functional for which the quadratic data fidelity term was replaced with a term based on the linear L1norm, resulting in what we have called an L2-L1 functional. The proposed method was tested in the livers and kidneys of two healthy volunteers under free-breathing conditions, on a data set comprising 3000 images equally divided between the volunteers. The results show that, compared to the existing approaches, our method demonstrates a greater robustness to local grey-level intensity variations introduced by arterial pulsations. Additionally, the computational time required by our implementation make it compatible with the work-flow of real-time MR-guided beam interventions. To the best of our knowledge this study was the first to analyse the behaviour of an L1-based optical flow functional in an applicative context: real-time MR-guidance of beam therapies in moving organs.

TH-AB-202-02: Real-Time Verification and Error Detection for MLC Tracking Deliveries Using An Electronic Portal Imaging Device

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

J Zwan, B; Central Coast Cancer Centre, Gosford, NSW; Colvill, E

2016-06-15

Purpose: The added complexity of the real-time adaptive multi-leaf collimator (MLC) tracking increases the likelihood of undetected MLC delivery errors. In this work we develop and test a system for real-time delivery verification and error detection for MLC tracking radiotherapy using an electronic portal imaging device (EPID). Methods: The delivery verification system relies on acquisition and real-time analysis of transit EPID image frames acquired at 8.41 fps. In-house software was developed to extract the MLC positions from each image frame. Three comparison metrics were used to verify the MLC positions in real-time: (1) field size, (2) field location and, (3)more » field shape. The delivery verification system was tested for 8 VMAT MLC tracking deliveries (4 prostate and 4 lung) where real patient target motion was reproduced using a Hexamotion motion stage and a Calypso system. Sensitivity and detection delay was quantified for various types of MLC and system errors. Results: For both the prostate and lung test deliveries the MLC-defined field size was measured with an accuracy of 1.25 cm{sup 2} (1 SD). The field location was measured with an accuracy of 0.6 mm and 0.8 mm (1 SD) for lung and prostate respectively. Field location errors (i.e. tracking in wrong direction) with a magnitude of 3 mm were detected within 0.4 s of occurrence in the X direction and 0.8 s in the Y direction. Systematic MLC gap errors were detected as small as 3 mm. The method was not found to be sensitive to random MLC errors and individual MLC calibration errors up to 5 mm. Conclusion: EPID imaging may be used for independent real-time verification of MLC trajectories during MLC tracking deliveries. Thresholds have been determined for error detection and the system has been shown to be sensitive to a range of delivery errors.« less

Differential Diagnosis of Malaria on Truelab Uno®, a Portable, Real-Time, MicroPCR Device for Point-Of-Care Applications.

PubMed

Nair, Chandrasekhar Bhaskaran; Manjula, Jagannath; Subramani, Pradeep Annamalai; Nagendrappa, Prakash B; Manoj, Mulakkapurath Narayanan; Malpani, Sukriti; Pullela, Phani Kumar; Subbarao, Pillarisetti Venkata; Ramamoorthy, Siva; Ghosh, Susanta K

2016-01-01

Sensitive and specific detection of malarial parasites is crucial in controlling the significant malaria burden in the developing world. Also important is being able to identify life threatening Plasmodium falciparum malaria quickly and accurately to reduce malaria related mortality. Existing methods such as microscopy and rapid diagnostic tests (RDTs) have major shortcomings. Here, we describe a new real-time PCR-based diagnostic test device at point-of-care service for resource-limited settings. Truenat® Malaria, a chip-based microPCR test, was developed by bigtec Labs, Bangalore, India, for differential identification of Plasmodium falciparum and Plasmodium vivax parasites. The Truenat Malaria tests runs on bigtec's Truelab Uno® microPCR device, a handheld, battery operated, and easy-to-use real-time microPCR device. The performance of Truenat® Malaria was evaluated versus the WHO nested PCR protocol. The Truenat® Malaria was further evaluated in a triple-blinded study design using a sample panel of 281 specimens created from the clinical samples characterized by expert microscopy and a rapid diagnostic test kit by the National Institute of Malaria Research (NIMR). A comparative evaluation was done on the Truelab Uno® and a commercial real-time PCR system. The limit of detection of the Truenat Malaria assay was found to be <5 parasites/μl for both P. falciparum and P. vivax. The Truenat® Malaria test was found to have sensitivity and specificity of 100% each, compared to the WHO nested PCR protocol based on the evaluation of 100 samples. The sensitivity using expert microscopy as the reference standard was determined to be around 99.3% (95% CI: 95.5-99.9) at the species level. Mixed infections were identified more accurately by Truenat Malaria (32 samples identified as mixed) versus expert microscopy and RDTs which detected 4 and 5 mixed samples, respectively. The Truenat® Malaria microPCR test is a valuable diagnostic tool and implementation should be considered not only for malaria diagnosis but also for active surveillance and epidemiological intervention.

Differential Diagnosis of Malaria on Truelab Uno®, a Portable, Real-Time, MicroPCR Device for Point-Of-Care Applications

PubMed Central

Nair, Chandrasekhar Bhaskaran; Manjula, Jagannath; Subramani, Pradeep Annamalai; Nagendrappa, Prakash B.; Manoj, Mulakkapurath Narayanan; Malpani, Sukriti; Pullela, Phani Kumar; Subbarao, Pillarisetti Venkata; Ramamoorthy, Siva; Ghosh, Susanta K.

2016-01-01

Background Sensitive and specific detection of malarial parasites is crucial in controlling the significant malaria burden in the developing world. Also important is being able to identify life threatening Plasmodium falciparum malaria quickly and accurately to reduce malaria related mortality. Existing methods such as microscopy and rapid diagnostic tests (RDTs) have major shortcomings. Here, we describe a new real-time PCR-based diagnostic test device at point-of-care service for resource-limited settings. Methods Truenat® Malaria, a chip-based microPCR test, was developed by bigtec Labs, Bangalore, India, for differential identification of Plasmodium falciparum and Plasmodium vivax parasites. The Truenat Malaria tests runs on bigtec’s Truelab Uno® microPCR device, a handheld, battery operated, and easy-to-use real-time microPCR device. The performance of Truenat® Malaria was evaluated versus the WHO nested PCR protocol. The Truenat® Malaria was further evaluated in a triple-blinded study design using a sample panel of 281 specimens created from the clinical samples characterized by expert microscopy and a rapid diagnostic test kit by the National Institute of Malaria Research (NIMR). A comparative evaluation was done on the Truelab Uno® and a commercial real-time PCR system. Results The limit of detection of the Truenat Malaria assay was found to be <5 parasites/μl for both P. falciparum and P. vivax. The Truenat® Malaria test was found to have sensitivity and specificity of 100% each, compared to the WHO nested PCR protocol based on the evaluation of 100 samples. The sensitivity using expert microscopy as the reference standard was determined to be around 99.3% (95% CI: 95.5–99.9) at the species level. Mixed infections were identified more accurately by Truenat Malaria (32 samples identified as mixed) versus expert microscopy and RDTs which detected 4 and 5 mixed samples, respectively. Conclusion The Truenat® Malaria microPCR test is a valuable diagnostic tool and implementation should be considered not only for malaria diagnosis but also for active surveillance and epidemiological intervention. PMID:26784111

A New ELISA Using the ANANAS Technology Showing High Sensitivity to diagnose the Bovine Rhinotracheitis from Individual Sera to Pooled Milk.

PubMed

Casarin, Elisabetta; Lucchese, Laura; Grazioli, Santina; Facchin, Sonia; Realdon, Nicola; Brocchi, Emiliana; Morpurgo, Margherita; Nardelli, Stefano

2016-01-01

Diagnostic tests for veterinary surveillance programs should be efficient, easy to use and, possibly, economical. In this context, classic Enzyme linked ImmunoSorbent Assay (ELISA) remains the most common analytical platform employed for serological analyses. The analysis of pooled samples instead of individual ones is a common procedure that permits to certify, with one single test, entire herds as "disease-free". However, diagnostic tests for pooled samples need to be particularly sensitive, especially when the levels of disease markers are low, as in the case of anti-BoHV1 antibodies in milk as markers of Infectious Bovine Rhinotracheitis (IBR) disease. The avidin-nucleic-acid-nanoassembly (ANANAS) is a novel kind of signal amplification platform for immunodiagnostics based on colloidal poly-avidin nanoparticles that, using model analytes, was shown to strongly increase ELISA test performance as compared to monomeric avidin. Here, for the first time, we applied the ANANAS reagent integration in a real diagnostic context. The monoclonal 1G10 anti-bovine IgG1 antibody was biotinylated and integrated with the ANANAS reagents for indirect IBR diagnosis from pooled milk mimicking tank samples from herds with IBR prevalence between 1 to 8%. The sensitivity and specificity of the ANANAS integrated method was compared to that of a classic test based on the same 1G10 antibody directly linked to horseradish peroxidase, and a commercial IDEXX kit recently introduced in the market. ANANAS integration increased by 5-fold the sensitivity of the 1G10 mAb-based conventional ELISA without loosing specificity. When compared to the commercial kit, the 1G10-ANANAS integrated method was capable to detect the presence of anti-BHV1 antibodies from bulk milk of gE antibody positive animals with 2-fold higher sensitivity and similar specificity. The results demonstrate the potentials of this new amplification technology, which permits improving current classic ELISA sensitivity limits without the need for new hardware investments.

A System and Method for Online High-Resolution Mapping of Gastric Slow-Wave Activity

PubMed Central

Bull, Simon H.; O’Grady, Gregory; Du, Peng

2015-01-01

High-resolution (HR) mapping employs multielectrode arrays to achieve spatially detailed analyses of propagating bioelectrical events. A major current limitation is that spatial analyses must currently be performed “off-line” (after experiments), compromising timely recording feedback and restricting experimental interventions. These problems motivated development of a system and method for “online” HR mapping. HR gastric recordings were acquired and streamed to a novel software client. Algorithms were devised to filter data, identify slow-wave events, eliminate corrupt channels, and cluster activation events. A graphical user interface animated data and plotted electrograms and maps. Results were compared against off-line methods. The online system analyzed 256-channel serosal recordings with no unexpected system terminations with a mean delay 18 s. Activation time marking sensitivity was 0.92; positive predictive value was 0.93. Abnormal slow-wave patterns including conduction blocks, ectopic pacemaking, and colliding wave fronts were reliably identified. Compared to traditional analysis methods, online mapping had comparable results with equivalent coverage of 90% of electrodes, average RMS errors of less than 1 s, and CC of activation maps of 0.99. Accurate slow-wave mapping was achieved in near real-time, enabling monitoring of recording quality and experimental interventions targeted to dysrhythmic onset. This work also advances the translation of HR mapping toward real-time clinical application. PMID:24860024

Flow Control and Routing in an Integrated Voice and Data Communication Network

DTIC Science & Technology

1981-08-01

require continuous and almost real - time delivery; they are very sensitive to delay. Data conversations, on the other hand, are generally intolerant of...packets arrive in time to be delivered to the sink. However, this is not the solution we seek. We have noted that voice conversations require almost real ...by long messages that require continuous real - time delivery; e.g. voice facsimile, video. Class II: characterized by short discrete messages that

Development and comparative evaluation of SYBR Green I-based one-step real-time RT-PCR assay for detection and quantification of West Nile virus in human patients.

PubMed

Kumar, Jyoti S; Saxena, Divyasha; Parida, Manmohan

2014-01-01

The recent outbreaks of West Nile Virus (WNV) in the Northeastern American continents and other regions of the world have made it essential to develop an efficient protocol for surveillance of WN virus. Nucleic acid based techniques like, RT-PCR have the advantage of sensitivity, specificity and rapidity. A one step single tube Env gene specific real-time RT-PCR was developed for early and reliable clinical diagnosis of WNV infection in clinical samples. The applicability of this assay for clinical diagnosis was validated with 105 suspected acute-phase serum and plasma samples from the recent epidemic of mysterious fever in Tamil Nadu, India in 2009-10. The comparative evaluation revealed the higher sensitivity of real-time RT-PCR assay by picking up 4 additional samples with low copy number of template in comparison to conventional RT-PCR. All the real-time positive samples further confirmed by CDC reported TaqMan real-time RT-PCR and quantitative real-time RT-PCR assays for the simultaneous detection of WNV lineage 1 and 2 strains. The quantitation of the viral load samples was done using a standard curve. These findings demonstrated that the assay has the potential usefulness for clinical diagnosis due to detection and quantification of WNV in acute-phase patient serum samples. Copyright © 2014 Elsevier Ltd. All rights reserved.

Approaching near real-time biosensing: microfluidic microsphere based biosensor for real-time analyte detection.

PubMed

Cohen, Noa; Sabhachandani, Pooja; Golberg, Alexander; Konry, Tania

2015-04-15

In this study we describe a simple lab-on-a-chip (LOC) biosensor approach utilizing well mixed microfluidic device and a microsphere-based assay capable of performing near real-time diagnostics of clinically relevant analytes such cytokines and antibodies. We were able to overcome the adsorption kinetics reaction rate-limiting mechanism, which is diffusion-controlled in standard immunoassays, by introducing the microsphere-based assay into well-mixed yet simple microfluidic device with turbulent flow profiles in the reaction regions. The integrated microsphere-based LOC device performs dynamic detection of the analyte in minimal amount of biological specimen by continuously sampling micro-liter volumes of sample per minute to detect dynamic changes in target analyte concentration. Furthermore we developed a mathematical model for the well-mixed reaction to describe the near real time detection mechanism observed in the developed LOC method. To demonstrate the specificity and sensitivity of the developed real time monitoring LOC approach, we applied the device for clinically relevant analytes: Tumor Necrosis Factor (TNF)-α cytokine and its clinically used inhibitor, anti-TNF-α antibody. Based on the reported results herein, the developed LOC device provides continuous sensitive and specific near real-time monitoring method for analytes such as cytokines and antibodies, reduces reagent volumes by nearly three orders of magnitude as well as eliminates the washing steps required by standard immunoassays. Copyright © 2014 Elsevier B.V. All rights reserved.

Rapid detection of highly pathogenic porcine reproductive and respiratory syndrome virus by a fluorescent probe-based isothermal recombinase polymerase amplification assay.

PubMed

Yang, Yang; Qin, Xiaodong; Sun, Yingjun; Chen, Ting; Zhang, Zhidong

2016-12-01

A novel fluorescent probe-based real-time reverse transcription recombinase polymerase amplification (real-time RT-RPA) assay was developed for rapid detection of highly pathogenic type 2 porcine reproductive and respiratory syndrome virus (HP-PRRSV). The sensitivity analysis showed that the detection limit of RPA was 70 copies of HP-PRRSV RNA/reaction. The real-time RT-RPA highly specific amplified HP-PRRSV with no cross-reaction with classic PRRSV, classic swine fever virus, pseudorabies virus, and foot-and-mouth disease virus. Assessment with 125 clinical samples showed that the developed real-time RT-RPA assay was well correlated with real-time RT-qPCR assays for detection of HP-PRRSV. These results suggest that the developed real-time RT-RPA assay is suitable for rapid detection of HP-PRRSV.

Skin-interfaced systems for sweat collection and analytics

PubMed Central

Choi, Jungil; Ghaffari, Roozbeh; Baker, Lindsay B.; Rogers, John A.

2018-01-01

Recent interdisciplinary advances in materials, mechanics, and microsystem designs for biocompatible electronics, soft microfluidics, and electrochemical biosensors establish the foundations for emerging classes of thin, skin-interfaced platforms capable of capturing, storing, and performing quantitative, spatiotemporal measurements of sweat chemistry, instantaneous local sweat rate, and total sweat loss. This review summarizes scientific and technical progress in this area and highlights the implications in real time and ambulatory modes of deployment during physical activities across a broad range of contexts in clinical health, physiology research, fitness/wellness, and athletic performance. PMID:29487915

Psychodynamic Factors Behind Online Social Networking and its Excessive Use.

PubMed

Li, Thomas Cheuk Wing

2016-03-01

This article discusses the psychodynamic factors behind the popularity of one form of Internet activity, online social networking (SN). It views online SN as an extension of the social self, organized in a way that is more controllable than real life relating. The SN platforms reward its users with reassuring surfaces and novel self-object experiences while at the same time induces much anxiety. The addictive quality of online SN is understood in the context of collapse of dialectical space and the defensive use of this technology.

Identification and Characterization of the V(D)J Recombination Activating Gene 1 in Long-Term Memory of Context Fear Conditioning

PubMed Central

Castro-Pérez, Edgardo; Soto-Soto, Emilio; Pérez-Carambot, Marizabeth; Dionisio-Santos, Dawling; Saied-Santiago, Kristian; Ortiz-Zuazaga, Humberto G.; Peña de Ortiz, Sandra

2016-01-01

An increasing body of evidence suggests that mechanisms related to the introduction and repair of DNA double strand breaks (DSBs) may be associated with long-term memory (LTM) processes. Previous studies from our group suggested that factors known to function in DNA recombination/repair machineries, such as DNA ligases, polymerases, and DNA endonucleases, play a role in LTM. Here we report data using C57BL/6 mice showing that the V(D)J recombination-activating gene 1 (RAG1), which encodes a factor that introduces DSBs in immunoglobulin and T-cell receptor genes, is induced in the amygdala, but not in the hippocampus, after context fear conditioning. Amygdalar induction of RAG1 mRNA, measured by real-time PCR, was not observed in context-only or shock-only controls, suggesting that the context fear conditioning response is related to associative learning processes. Furthermore, double immunofluorescence studies demonstrated the neuronal localization of RAG1 protein in amygdalar sections prepared after perfusion and fixation. In functional studies, intra-amygdalar injections of RAG1 gapmer antisense oligonucleotides, given 1 h prior to conditioning, resulted in amygdalar knockdown of RAG1 mRNA and a significant impairment in LTM, tested 24 h after training. Overall, these findings suggest that the V(D)J recombination-activating gene 1, RAG1, may play a role in LTM consolidation. PMID:26843989

Development of SYBR Green I Based Real-Time RT-PCR Assay for Specific Detection of Watermelon silver mottle Virus.

PubMed

Rao, Xueqin; Sun, Jie

2015-09-01

Watermelon silver mottle virus (WSMoV), which belongs to the genus Tospovirus , causes significant loss in Cucurbitaceae plants. Development of a highly sensitive and reliable detection method for WSMoV. Recombinant plasmids for targeting the sequence of nucleocapsid protein gene of WSMoV were constructed. SYBR Green I real-time PCR was established and evaluated with standard recombinant plasmids and 27 watermelon samples showing WSMoV infection symptoms. The recombinant plasmid was used as template for SYBR Green I real-time PCR to generate standard and melting curves. Melting curve analysis indicated no primer-dimers and non-specific products in the assay. No cross-reaction was observed with Capsicum chlorosis virus (genus Tospovirus ) and Cucumber mosaic virus (genus Cucumovirus). Repeatability tests indicated that inter-assay variability of the Ct values was 1.6%. A highly sensitive, reliable and rapid detection method of SYBR Green I real-time PCR for timely detection of WSMoV plants and vector thrips was established, which will facilitate disease forecast and control.

Development and validation of a Pneumocystis jirovecii real-time polymerase chain reaction assay for diagnosis of Pneumocystis pneumonia

PubMed Central

Church, Deirdre L; Ambasta, Anshula; Wilmer, Amanda; Williscroft, Holly; Ritchie, Gordon; Pillai, Dylan R; Champagne, Sylvie; Gregson, Daniel G

2015-01-01

BACKGROUND: Pneumocystis jirovecii (PJ), a pathogenic fungus, causes severe interstitial Pneumocystis pneumonia (PCP) among immunocompromised patients. A laboratory-developed real-time polyermase chain reaction (PCR) assay was validated for PJ detection to improve diagnosis of PCP. METHODS: Forty stored bronchoalveolar lavage (BAL) samples (20 known PJ positive [PJ+] and 20 known PJ negative [PJ−]) were initially tested using the molecular assay. Ninety-two sequentially collected BAL samples were then analyzed using an immunofluorescence assay (IFA) and secondarily tested using the PJ real-time PCR assay. Discrepant results were resolved by retesting BAL samples using another real-time PCR assay with a different target. PJ real-time PCR assay performance was compared with the existing gold standard (ie, IFA) and a modified gold standard, in which a true positive was defined as a sample that tested positive in two of three methods in a patient suspected to have PCP. RESULTS: Ninety of 132 (68%) BAL fluid samples were collected from immunocompromised patients. Thirteen of 92 (14%) BALs collected were PJ+ when tested using IFA. A total of 40 BAL samples were PJ+ in the present study including: all IFA positive samples (n=13); all referred PJ+ BAL samples (n=20); and seven additional BAL samples that were IFA negative, but positive using the modified gold standard. Compared with IFA, the PJ real-time PCR had sensitivity, specificity, and positive and negative predictive values of 100%, 91%, 65% and 100%, respectively. Compared with the modified gold standard, PJ real-time PCR had a sensitivity, specificity, and positive and negative predictive values of 100%. CONCLUSION: PJ real-time PCR improved detection of PJ in immunocompromised patients. PMID:26600815

Comparison of Two Commercial Automated Nucleic Acid Extraction and Integrated Quantitation Real-Time PCR Platforms for the Detection of Cytomegalovirus in Plasma

PubMed Central

Tsai, Huey-Pin; Tsai, You-Yuan; Lin, I-Ting; Kuo, Pin-Hwa; Chen, Tsai-Yun; Chang, Kung-Chao; Wang, Jen-Ren

2016-01-01

Quantitation of cytomegalovirus (CMV) viral load in the transplant patients has become a standard practice for monitoring the response to antiviral therapy. The cut-off values of CMV viral load assays for preemptive therapy are different due to the various assay designs employed. To establish a sensitive and reliable diagnostic assay for preemptive therapy of CMV infection, two commercial automated platforms including m2000sp extraction system integrated the Abbott RealTime (m2000rt) and the Roche COBAS AmpliPrep for extraction integrated COBAS Taqman (CAP/CTM) were evaluated using WHO international CMV standards and 110 plasma specimens from transplant patients. The performance characteristics, correlation, and workflow of the two platforms were investigated. The Abbott RealTime assay correlated well with the Roche CAP/CTM assay (R2 = 0.9379, P<0.01). The Abbott RealTime assay exhibited higher sensitivity for the detection of CMV viral load, and viral load values measured with Abbott RealTime assay were on average 0.76 log10 IU/mL higher than those measured with the Roche CAP/CTM assay (P<0.0001). Workflow analysis on a small batch size at one time, using the Roche CAP/CTM platform had a shorter hands-on time than the Abbott RealTime platform. In conclusion, these two assays can provide reliable data for different purpose in a clinical virology laboratory setting. PMID:27494707

Through the Lens of Cultural Awareness: A Primer for US Armed Forces Deploying to Arab and Middle Eastern Countries

DTIC Science & Technology

2006-01-01

Willingness to Compromise •Risk Avoidance •Time to Decision •Etc. The “What” ral Variation Behaviors •Context Sensitivity Values •Individualism vs ...Collectivism •Power Distance •Formality vs . informality •Uncertainty Avoidance •Relationship vs . Deal Focus •Long-term vs . Short term orientation •Time...Orientation Cognition •Reasoning Styles Cultural Variations Behaviors •Context Sensitivity Values •Individualism vs . Collectivism •Power Distance •Formality

Time-dependent effects of prazosin on the development of methamphetamine conditioned hyperactivity and context-specific sensitization in mice.

PubMed

White, André O; Rauhut, Anthony S

2014-04-15

The present experiments examined the effects of prazosin, a selective α₁-adrenergic receptor antagonist, on the development of methamphetamine conditioned hyperactivity and context-specific sensitization. Mice received an injection of vehicle (distilled water) or prazosin (0.5, 1.0 or 2.0 mg/kg) 30 min prior to a second injection of vehicle (saline) or methamphetamine (1.0 mg/kg) during the conditioning sessions (Experiment 1). Following the conditioning sessions, mice were tested for conditioned hyperactivity and then tested for context-specific sensitization. In subsequent experiments, mice received an injection of vehicle (distilled water) or prazosin (2.0 mg/kg) immediately (Experiment 2) or 24 h (Experiment 3) after the conditioning sessions and then tested for conditioned hyperactivity and context-specific sensitization. Prazosin dose-dependently blocked the development of methamphetamine conditioned hyperactivity and context-specific sensitization when administered prior to the methamphetamine during the conditioning phase; however nonspecific motor impairments also were observed (Experiment 1). Immediate (Experiment 2), but not the 24-h delay (Experiment 3), post-session administration of prazosin attenuated the development of methamphetamine conditioned hyperactivity and context-specific sensitization. Nonspecific motor impairments were not observed in these latter experiments. Collectively, these results suggest that the α₁-adrenergic receptor mediates the development of methamphetamine-conditioned hyperactivity and context-specific sensitization, perhaps by altering memory consolidation and/or reconsolidation processes. Copyright © 2014 Elsevier B.V. All rights reserved.

Context-sensitive autoassociative memories as expert systems in medical diagnosis

PubMed Central

Pomi, Andrés; Olivera, Fernando

2006-01-01

Background The complexity of our contemporary medical practice has impelled the development of different decision-support aids based on artificial intelligence and neural networks. Distributed associative memories are neural network models that fit perfectly well to the vision of cognition emerging from current neurosciences. Methods We present the context-dependent autoassociative memory model. The sets of diseases and symptoms are mapped onto a pair of basis of orthogonal vectors. A matrix memory stores the associations between the signs and symptoms, and their corresponding diseases. A minimal numerical example is presented to show how to instruct the memory and how the system works. In order to provide a quick appreciation of the validity of the model and its potential clinical relevance we implemented an application with real data. A memory was trained with published data of neonates with suspected late-onset sepsis in a neonatal intensive care unit (NICU). A set of personal clinical observations was used as a test set to evaluate the capacity of the model to discriminate between septic and non-septic neonates on the basis of clinical and laboratory findings. Results We show here that matrix memory models with associations modulated by context can perform automatic medical diagnosis. The sequential availability of new information over time makes the system progress in a narrowing process that reduces the range of diagnostic possibilities. At each step the system provides a probabilistic map of the different possible diagnoses to that moment. The system can incorporate the clinical experience, building in that way a representative database of historical data that captures geo-demographical differences between patient populations. The trained model succeeds in diagnosing late-onset sepsis within the test set of infants in the NICU: sensitivity 100%; specificity 80%; percentage of true positives 91%; percentage of true negatives 100%; accuracy (true positives plus true negatives over the totality of patients) 93,3%; and Cohen's kappa index 0,84. Conclusion Context-dependent associative memories can operate as medical expert systems. The model is presented in a simple and tutorial way to encourage straightforward implementations by medical groups. An application with real data, presented as a primary evaluation of the validity and potentiality of the model in medical diagnosis, shows that the model is a highly promising alternative in the development of accuracy diagnostic tools. PMID:17121675

Hippocampal mechanisms for the context-dependent retrieval of episodes

PubMed Central

Hasselmo, Michael E.; Eichenbaum, Howard B.

2008-01-01

Behaviors ranging from delivering newspapers to waiting tables depend on remembering previous episodes to avoid incorrect repetition. Physiologically, this requires mechanisms for long-term storage and selective retrieval of episodes based on time of occurrence, despite variable intervals and similarity of events in a familiar environment. Here, this process has been modeled based on physiological properties of the hippocampal formation, including mechanisms for sustained activity in entorhinal cortex and theta rhythm oscillations in hippocampal subregions. The model simulates the context-sensitive firing properties of hippocampal neurons including trial specific firing during spatial alternation and trial by trial changes in theta phase precession on a linear track. This activity is used to guide behavior, and lesions of the hippocampal network impair memory-guided behavior. The model links data at the cellular level to behavior at the systems level, describing a physiologically plausible mechanism for the brain to recall a given episode which occurred at a specific place and time. PMID:16263240

[Autochthonous acute viral and bacterial infections of the central nervous system (meningitis and encephalitis)].

PubMed

Pérez-Ruiz, Mercedes; Vicente, Diego; Navarro-Marí, José María

2008-07-01

Rapid diagnosis of acute viral and bacterial infections of the central nervous system (meningitis and encephalitis) is highly important for the clinical management of the patient and helps to establish early therapy that may solve life-threatening situations, to avoid unnecessary empirical treatments, to reduce hospital stay, and to facilitate appropriate interventions in the context of public health. Molecular techniques, especially real-time polymerase chain reaction, have become the fastest and most sensitive diagnostic procedures for autochthonous viral meningitis and encephalitis, and their role is becoming increasingly important for the diagnosis and control of most frequent acute bacterial meningitides. Automatic and closed systems may encourage the widespread and systematic use of molecular techniques for the diagnosis of these neurological syndromes in most laboratories.

Real-time functional mapping: potential tool for improving language outcome in pediatric epilepsy surgery

PubMed Central

Korostenskaja, Milena; Chen, Po-Ching; Salinas, Christine M.; Westerveld, Michael; Brunner, Peter; Schalk, Gerwin; Cook, Jane C.; Baumgartner, James; Lee, Ki H.

2015-01-01

Accurate language localization expands surgical treatment options for epilepsy patients and reduces the risk of postsurgery language deficits. Electrical cortical stimulation mapping (ESM) is considered to be the clinical gold standard for language localization. While ESM affords clinically valuable results, it can be poorly tolerated by children, requires active participation and compliance, carries a risk of inducing seizures, is highly time consuming, and is labor intensive. Given these limitations, alternative and/or complementary functional localization methods such as analysis of electrocorticographic (ECoG) activity in high gamma frequency band in real time are needed to precisely identify eloquent cortex in children. In this case report, the authors examined 1) the use of real-time functional mapping (RTFM) for language localization in a high gamma frequency band derived from ECoG to guide surgery in an epileptic pediatric patient and 2) the relationship of RTFM mapping results to postsurgical language outcomes. The authors found that RTFM demonstrated relatively high sensitivity (75%) and high specificity (90%) when compared with ESM in a “next-neighbor” analysis. While overlapping with ESM in the superior temporal region, RTFM showed a few other areas of activation related to expressive language function, areas that were eventually resected during the surgery. The authors speculate that this resection may be associated with observed postsurgical expressive language deficits. With additional validation in more subjects, this finding would suggest that surgical planning and associated assessment of the risk/benefit ratio would benefit from information provided by RTFM mapping. PMID:24995815

Biomass burning source characterization requirements in air quality models with and without data assimilation: challenges and opportunities

NASA Astrophysics Data System (ADS)

Hyer, E. J.; Zhang, J. L.; Reid, J. S.; Curtis, C. A.; Westphal, D. L.

2007-12-01

Quantitative models of the transport and evolution of atmospheric pollution have graduated from the laboratory to become a part of the operational activity of forecast centers. Scientists studying the composition and variability of the atmosphere put great efforts into developing methods for accurately specifying sources of pollution, including natural and anthropogenic biomass burning. These methods must be adapted for use in operational contexts, which impose additional strictures on input data and methods. First, only input data sources available in near real-time are suitable for use in operational applications. Second, operational applications must make use of redundant data sources whenever possible. This is a shift in philosophy: in a research context, the most accurate and complete data set will be used, whereas in an operational context, the system must be designed with maximum redundancy. The goal in an operational context is to produce, to the extent possible, consistent and timely output, given sometimes inconsistent inputs. The Naval Aerosol Analysis and Prediction System (NAAPS), a global operational aerosol analysis and forecast system, recently began incorporating assimilation of satellite-derived aerosol optical depth. Assimilation of satellite AOD retrievals has dramatically improved aerosol analyses and forecasts from this system. The use of aerosol data assimilation also changes the strategy for improving the smoke source function. The absolute magnitude of emissions events can be refined through feedback from the data assimilation system, both in real- time operations and in post-processing analysis of data assimilation results. In terms of the aerosol source functions, the largest gains in model performance are now to be gained by reducing data latency and minimizing missed detections. In this presentation, recent model development work on the Fire Locating and Monitoring of Burning Emissions (FLAMBE) system that provides smoke aerosol boundary conditions for NAAPS is described, including redundant integration of multiple satellite platforms and development of feedback loops between the data assimilation system and smoke source.

Performance of a commercial assay for the diagnosis of influenza A (H1N1) infection in comparison to the Centers for Disease Control and Prevention protocol of real time RT-PCR.

PubMed

Barbás, María G; Gallego, Sandra V; Castro, Gonzalo M; Baumeister, Elsa; Kademian, Silvia; De Leon, Juan; Cudolá, Analía

2012-01-01

At the time of influenza A (H1N1) emergency, the WHO responded with remarkable speed by releasing guidelines and a protocol for a real-time RT-PCR assay (rRT-PCR). The aim of the present study was to evalúate the performance of the "Real Time Ready Influenza A/H1N1 Detection Set" (June 2009)-Roche kit in comparison to the CDC reference rRT-PCR protocol. The overall sensitivity of the Roche assay for detection of the Inf A gene in the presence or absence of the H1 gene was 74.5 %. The sensitivity for detecting samples that were only positive for the Inf A gene (absence of the H1 gene) was 53.3 % whereas the sensitivity for H1N1-positive samples (presence of the Inf A gene and any other swine gene) was 76.4 %. The specificity of the assay was 97.1 %. A new version of the kit (November 2009) is now available, and a recent evaluation of its performance showed good sensitivity to detect pandemic H1N1 compared to other molecular assays.

A Context-Aware Knowledge Map to Support Ubiquitous Learning Activities for a u-Botanical Museum

ERIC Educational Resources Information Center

Wang, Shu-Lin; Chen, Chia-Chen; Zhang, Zhe George

2015-01-01

Recent developments in mobile and wireless communication technologies have played a vital role in building the u-learning environment that now combines both real-world and digital learning resources. However, learners still require assistance to control real objects and manage the abundance of available materials; otherwise, their mental workload…

Metaphor as a Possible Pathway to More Formal Understanding of the Definition of Sequence Convergence

ERIC Educational Resources Information Center

Dawkins, Paul Christian

2012-01-01

This study presents how the introduction of a metaphor for sequence convergence constituted an experientially real context in which an undergraduate real analysis student developed a property-based definition of sequence convergence. I use elements from Zandieh and Rasmussen's (2010) Defining as a Mathematical Activity framework to trace the…

Real-Time Imaging Reveals the Dynamics of Leukocyte Behaviour during Experimental Cerebral Malaria Pathogenesis

PubMed Central

Pai, Saparna; Qin, Jim; Cavanagh, Lois; Mitchell, Andrew; El-Assaad, Fatima; Jain, Rohit; Combes, Valery; Hunt, Nicholas H.; Grau, Georges E. R.; Weninger, Wolfgang

2014-01-01

During experimental cerebral malaria (ECM) mice develop a lethal neuropathological syndrome associated with microcirculatory dysfunction and intravascular leukocyte sequestration. The precise spatio-temporal context in which the intravascular immune response unfolds is incompletely understood. We developed a 2-photon intravital microscopy (2P-IVM)-based brain-imaging model to monitor the real-time behaviour of leukocytes directly within the brain vasculature during ECM. Ly6Chi monocytes, but not neutrophils, started to accumulate in the blood vessels of Plasmodium berghei ANKA (PbA)-infected MacGreen mice, in which myeloid cells express GFP, one to two days prior to the onset of the neurological signs (NS). A decrease in the rolling speed of monocytes, a measure of endothelial cell activation, was associated with progressive worsening of clinical symptoms. Adoptive transfer experiments with defined immune cell subsets in recombinase activating gene (RAG)-1-deficient mice showed that these changes were mediated by Plasmodium-specific CD8+ T lymphocytes. A critical number of CD8+ T effectors was required to induce disease and monocyte adherence to the vasculature. Depletion of monocytes at the onset of disease symptoms resulted in decreased lymphocyte accumulation, suggesting reciprocal effects of monocytes and T cells on their recruitment within the brain. Together, our studies define the real-time kinetics of leukocyte behaviour in the central nervous system during ECM, and reveal a significant role for Plasmodium-specific CD8+ T lymphocytes in regulating vascular pathology in this disease. PMID:25033406

Optimized quantum sensing with a single electron spin using real-time adaptive measurements.

PubMed

Bonato, C; Blok, M S; Dinani, H T; Berry, D W; Markham, M L; Twitchen, D J; Hanson, R

2016-03-01

Quantum sensors based on single solid-state spins promise a unique combination of sensitivity and spatial resolution. The key challenge in sensing is to achieve minimum estimation uncertainty within a given time and with high dynamic range. Adaptive strategies have been proposed to achieve optimal performance, but their implementation in solid-state systems has been hindered by the demanding experimental requirements. Here, we realize adaptive d.c. sensing by combining single-shot readout of an electron spin in diamond with fast feedback. By adapting the spin readout basis in real time based on previous outcomes, we demonstrate a sensitivity in Ramsey interferometry surpassing the standard measurement limit. Furthermore, we find by simulations and experiments that adaptive protocols offer a distinctive advantage over the best known non-adaptive protocols when overhead and limited estimation time are taken into account. Using an optimized adaptive protocol we achieve a magnetic field sensitivity of 6.1 ± 1.7 nT Hz(-1/2) over a wide range of 1.78 mT. These results open up a new class of experiments for solid-state sensors in which real-time knowledge of the measurement history is exploited to obtain optimal performance.

Optimized quantum sensing with a single electron spin using real-time adaptive measurements

NASA Astrophysics Data System (ADS)

Bonato, C.; Blok, M. S.; Dinani, H. T.; Berry, D. W.; Markham, M. L.; Twitchen, D. J.; Hanson, R.

2016-03-01

Quantum sensors based on single solid-state spins promise a unique combination of sensitivity and spatial resolution. The key challenge in sensing is to achieve minimum estimation uncertainty within a given time and with high dynamic range. Adaptive strategies have been proposed to achieve optimal performance, but their implementation in solid-state systems has been hindered by the demanding experimental requirements. Here, we realize adaptive d.c. sensing by combining single-shot readout of an electron spin in diamond with fast feedback. By adapting the spin readout basis in real time based on previous outcomes, we demonstrate a sensitivity in Ramsey interferometry surpassing the standard measurement limit. Furthermore, we find by simulations and experiments that adaptive protocols offer a distinctive advantage over the best known non-adaptive protocols when overhead and limited estimation time are taken into account. Using an optimized adaptive protocol we achieve a magnetic field sensitivity of 6.1 ± 1.7 nT Hz-1/2 over a wide range of 1.78 mT. These results open up a new class of experiments for solid-state sensors in which real-time knowledge of the measurement history is exploited to obtain optimal performance.

Evaluating the influence of wastewater composition on the growth of Microthrix parvicella by GCxGC/qMS and real-time PCR.

PubMed

Dunkel, Thiemo; de León Gallegos, Erika Lizette; Schönsee, Carina D; Hesse, Tobias; Jochmann, Maik; Wingender, Jost; Denecke, Martin

2016-01-01

This study underlines the significance of long chain fatty acid (LCFA) content in wastewater influents as an influencing factor promoting the growth of Candidatus 'Microthrix parvicella' (M. parvicella), the most common filamentous bacteria causing foam in activated sludge systems worldwide. Quantification of M. parvicella by real-time polymerase chain reaction (real-time PCR) and analysis of LCFAs by means of two-dimensional gas chromatography coupled with mass spectrometry (GCxGC/qMS), involving solid phase micro-extraction (SPME) to enhance sensitivity, were combined for the first time as a monitoring tool. The results indicate a highly significant correlation between the abundance of M. parvicella and the total LCFA loading (r = 0.96) and linolenic acid C18:3 (r = 0.98) in particular. Additionally, comparison of slope values for the direct correlations of all significant LCFAs found in the analyses showed that the influence of LCFAs on M. parvicella growth increases with an increasing degree of unsaturation of carbon chains. These findings suggest that by removing lipid compounds from the incoming waters, substrate availability would be limited for M. parvicella. Copyright © 2015 Elsevier Ltd. All rights reserved.

A viscosity sensitive fluorescent dye for real-time monitoring of mitochondria transport in neurons.

PubMed

Baek, Yeonju; Park, Sang Jun; Zhou, Xin; Kim, Gyungmi; Kim, Hwan Myung; Yoon, Juyoung

2016-12-15

We present here a viscosity sensitive fluorescent dye, namely thiophene dihemicyanine (TDHC), that enables the specific staining of mitochondria. In comparison to the common mitochondria tracker (Mitotracker Deep Red, MTDR), this dye demonstrated its unique ability for robust staining of mitochondria with high photostability and ultrahigh signal-to-noise ratio (SNR). Moreover, TDHC also showed high sensitivity towards mitochondria membrane potential (ΔΨm) and intramitochondria viscosity change. Consequently, this dye was utilized in real-time monitoring of mitochondria transport in primary cortical neurons. Finally, the Two-Photon Microscopy (TPM) imaging ability of TDHC was also demonstrated. Copyright © 2016 Elsevier B.V. All rights reserved.

A simple method to measure critical angles for high-sensitivity differential refractometry.

PubMed

Zilio, S C

2012-01-16

A total internal reflection-based differencial refractometer, capable of measuring the real and imaginary parts of the complex refractive index in real time, is presented. The device takes advantage of the phase difference acquired by s- and p-polarized light to generate an easily detectable minimum at the reflected profile. The method allows to sensitively measuring transparent and turbid liquid samples.

A framework for luck egalitarianism in health and healthcare.

PubMed

Albertsen, Andreas; Knight, Carl

2015-02-01

Several attempts have been made to apply the choice-sensitive theory of distributive justice, luck egalitarianism, in the context of health and healthcare. This article presents a framework for this discussion by highlighting different normative decisions to be made in such an application, some of the objections to which luck egalitarians must provide answers and some of the practical implications associated with applying such an approach in the real world. It is argued that luck egalitarians should address distributions of health rather than healthcare, endorse an integrationist theory that combines health concerns with general distributive concerns and be pluralist in their approach. It further suggests that choice-sensitive policies need not be the result of applying luck egalitarianism in this context. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Development of duplex real-time RT-PCR based on Taqman technology for detecting simultaneously the genome of pan-enterovirus and enterovirus 71.

PubMed

Hwang, Seoyeon; Kang, Byunghak; Hong, Jiyoung; Kim, Ahyoun; Kim, Hyejin; Kim, Kisang; Cheon, Doo-Sung

2013-07-01

Human enterovirus (EV) 71 is the main etiological agent of hand, foot, and mouth disease (HFMD). It is associated with neurological complications, and caused fatalities during recent outbreaks in the Asia-Pacific region. Infections caused by EV71 could lead to many complications, ranging from brainstem encephalitis to pulmonary oedema, resulting in high mortality. In this study, a duplex real-time RT-PCR assay was developed in order to simultaneously detect pan-EV and EV71. EV71-specific primers and probes were designed based on the highly conserved VP1 region of EV71. Five EV71 strains were detected as positive, and no positive fluorescence signal was observed in the duplex real-time RT-PCR for other viral RNA, which showed 100% specificity for the selected panel, and no cross-reactions were observed in this duplex real-time RT-PCR. The EV71-specific duplex real-time RT-PCR was more sensitive than conventional RT-PCR, and detected viral titers that were 10-fold lower than those measured by the latter. Of the 381 HFMD clinical specimens, 196 (51.4%) cases were pan-EV-positive, of which 170 (86.7%) were EV71-positive when tested by pan-EV and EV71-specific duplex real-time RT-PCR. EV71-specific duplex real-time RT-PCR offers a rapid and sensitive method to detect EV71 from clinical specimens, and will allow quarantine measures to be taken more effectively during outbreaks. Copyright © 2013 Wiley Periodicals, Inc.

Implementation of a Real-Time Stacking Algorithm in a Photogrammetric Digital Camera for Uavs

NASA Astrophysics Data System (ADS)

Audi, A.; Pierrot-Deseilligny, M.; Meynard, C.; Thom, C.

2017-08-01

In the recent years, unmanned aerial vehicles (UAVs) have become an interesting tool in aerial photography and photogrammetry activities. In this context, some applications (like cloudy sky surveys, narrow-spectral imagery and night-vision imagery) need a longexposure time where one of the main problems is the motion blur caused by the erratic camera movements during image acquisition. This paper describes an automatic real-time stacking algorithm which produces a high photogrammetric quality final composite image with an equivalent long-exposure time using several images acquired with short-exposure times. Our method is inspired by feature-based image registration technique. The algorithm is implemented on the light-weight IGN camera, which has an IMU sensor and a SoC/FPGA. To obtain the correct parameters for the resampling of images, the presented method accurately estimates the geometrical relation between the first and the Nth image, taking into account the internal parameters and the distortion of the camera. Features are detected in the first image by the FAST detector, than homologous points on other images are obtained by template matching aided by the IMU sensors. The SoC/FPGA in the camera is used to speed up time-consuming parts of the algorithm such as features detection and images resampling in order to achieve a real-time performance as we want to write only the resulting final image to save bandwidth on the storage device. The paper includes a detailed description of the implemented algorithm, resource usage summary, resulting processing time, resulting images, as well as block diagrams of the described architecture. The resulting stacked image obtained on real surveys doesn't seem visually impaired. Timing results demonstrate that our algorithm can be used in real-time since its processing time is less than the writing time of an image in the storage device. An interesting by-product of this algorithm is the 3D rotation estimated by a photogrammetric method between poses, which can be used to recalibrate in real-time the gyrometers of the IMU.

Implementing real-time GNSS monitoring to investigate continental rift initiation processes

NASA Astrophysics Data System (ADS)

Jones, J. R.; Stamps, D. S.; Wauthier, C.; Daniels, M. D.; Saria, E.; Ji, K. H.; Mencin, D.; Ntambila, D.

2017-12-01

Continental rift initiation remains an elusive, yet fundamental, process in the context of plate tectonic theory. Our early work in the Natron Rift, Tanzania, the Earth's archetype continental rift initiation setting, indicates feedback between volcanic deformation and fault slip play a key role in the rift initiation process. We found evidence that fault slip on the Natron border fault during active volcanism at Ol Doniyo Lengai in 2008 required only 0.01 MPa of Coulomb stress change. This previous study was limited by GPS constraints 18 km from the volcano, rather than immediately adjacent on the rift shoulder. We hypothesize that fault slip adjacent to the volcano creeps, and without the need for active eruption. We also hypothesize silent slip events may occur over time-scales less than 1 day. To test our hypotheses we designed a GNSS network with 4 sites on the flanks of Ol Doinyo Lengai and 1 site on the adjacent Natron border fault with the capability to calculate 1 second, 3-5 cm precision positions. Data is transmitted to UNAVCO in real-time with remote satellite internet, which we automatically import to the EarthCube building block CHORDS (Cloud Hosted Real-time Data Services for the Geosciences) using our newly developed method. We use CHORDS to monitor and evaluate the health of our network while visualizing the GNSS data in real-time. In addition to our import method we have also developed user-friendly capabilities to export GNSS positions (longitude, latitude, height) with CHORDS assuming the data are available at UNAVCO in NMEA standardized format through the Networked Transport of RTCM via Internet Protocol (NTRIP). The ability to access the GNSS data that continuously monitors volcanic deformation, tectonics, and their interactions on and around Ol Doinyo Lengai is a crucial component in our investigation of continental rift initiation in the Natron Rift, Tanzania. Our new user-friendly methods developed to access and post-process real-time GNSS positioning data can also be used by others in the geodesy community that need 3-5 cm precision positions (longitude, latitude, height).

Real-time notification and improved situational awareness in fire emergencies using geospatial-based publish/subscribe

NASA Astrophysics Data System (ADS)

Kassab, Ala'; Liang, Steve; Gao, Yang

2010-12-01

Emergency agencies seek to maintain situational awareness and effective decision making through continuous monitoring of, and real-time alerting about, sources of information regarding current incidents and developing fire hazards. The nature of this goal requires integrating different, potentially numerous, sources of dynamic geospatial information on the one side, and a large number of clients having heterogeneous and specific interests in data on the other side. In such scenarios, the traditional request/reply communication style may function inefficiently, as it is based on point-to-point, synchronous, and pulling mode interaction between consumer clients and information providers/services. In this work, we propose Geospatial-based Publish/ Subscribe, an interaction framework that serves as a middleware for real-time transacting of spatially related information of interest, termed geospatial events, in distributed systems. Expressive data models, including geospatial event and geospatial subscription, as well as an efficient matching approach for fast dissemination of geospatial events to interested clients, are introduced. The proposed interaction framework is realized through the development of a Real-Time Fire Emergency Response System (RFERS) prototype. The prototype is designed for transacting several topics of geospatial events that are crucial within the context of fire emergencies, including GPS locations of emergency assets, meteorological observations of wireless sensors, fire incidents reports, and temporal sequences of remote sensing images of active wildfires. The performance of the system prototype has been evaluated in order to demonstrate its efficiency.

Turning Transfer Inside Out: The Affordances of Virtual Worlds and Mobile Devices in Real World Contexts for Teaching about Causality across Time and Distance in Ecosystems

ERIC Educational Resources Information Center

Grotzer, Tina A.; Powell, Megan M.; Derbiszewska, Katarzyna M.; Courter, Caroline J.; Kamarainen, Amy M.; Metcalf, Shari J.; Dede, Christopher J.

2015-01-01

Reasoning about ecosystems includes consideration of causality over temporal and spatial distances; yet learners typically focus on immediate time frames and local contexts. Teaching students to reason beyond these boundaries has met with some success based upon tests that cue students to the types of reasoning required. Virtual worlds offer an…

Real-time gray-scale photolithography for fabrication of continuous microstructure

NASA Astrophysics Data System (ADS)

Peng, Qinjun; Guo, Yongkang; Liu, Shijie; Cui, Zheng

2002-10-01

A novel real-time gray-scale photolithography technique for the fabrication of continuous microstructures that uses a LCD panel as a real-time gray-scale mask is presented. The principle of design of the technique is explained, and computer simulation results based on partially coherent imaging theory are given for the patterning of a microlens array and a zigzag grating. An experiment is set up, and a microlens array and a zigzag grating on panchromatic silver halide sensitized gelatin with trypsinase etching are obtained.

Short communication: Early modification of the circadian organization of cow activity in relation to disease or estrus.

PubMed

Veissier, Isabelle; Mialon, Marie-Madeleine; Sloth, Karen Helle

2017-05-01

Biological rhythms are an essential regulator of life. There is evidence that circadian rhythm of activity is disrupted under chronic stress in animals and humans, and it may also be less marked during diseases. Here we investigated whether a detectable circadian rhythm of activity exists in dairy cows in commercial settings using a real-time positioning system. We used CowView (GEA Farm Technologies) to regularly record the individual positions of 350 cows in a Danish dairy farm over 5 mo and to infer the cows' activity (resting, feeding, in alley). We ran a factorial correspondence analysis on the cows' activities and used the first component of this analysis to express the variations in activity. On this axis, the activities obtained the following weights: resting = -0.15; in alleys = +0.12; feeding = +0.34. By applying these weights to the proportions of time each cow spent on each of the 3 activities, we were able to chart a circadian rhythm of activity. We found that average level of activity of a cow on a given day and its variations during that day varied with specific states (i.e., estrus, lameness, mastitis). More specifically, circadian variations in activity appeared to be particularly sensitive and to vary 1 to 2 d before the farmer detected a disorder. These findings offer promising avenues for further research to design models to predict physiological or pathological states of cows from real-time positioning data. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Decoding brain activity using a large-scale probabilistic functional-anatomical atlas of human cognition

PubMed Central

Jones, Michael N.

2017-01-01

A central goal of cognitive neuroscience is to decode human brain activity—that is, to infer mental processes from observed patterns of whole-brain activation. Previous decoding efforts have focused on classifying brain activity into a small set of discrete cognitive states. To attain maximal utility, a decoding framework must be open-ended, systematic, and context-sensitive—that is, capable of interpreting numerous brain states, presented in arbitrary combinations, in light of prior information. Here we take steps towards this objective by introducing a probabilistic decoding framework based on a novel topic model—Generalized Correspondence Latent Dirichlet Allocation—that learns latent topics from a database of over 11,000 published fMRI studies. The model produces highly interpretable, spatially-circumscribed topics that enable flexible decoding of whole-brain images. Importantly, the Bayesian nature of the model allows one to “seed” decoder priors with arbitrary images and text—enabling researchers, for the first time, to generate quantitative, context-sensitive interpretations of whole-brain patterns of brain activity. PMID:29059185

On-a-chip biosensing with nano-optical resonators (Conference Presentation)

NASA Astrophysics Data System (ADS)

Quidant, Romain; Yavas, Ozlem; Sanz, Vanesa; Acimovic, Srdjan; Dobosz, Paulina

2016-09-01

Optical biosensing based on gold nanoparticles supporting localized surface plasmoncs (LSPR) potentially offers great opportunities for compact, sensitive and low cost diagnostic devices. While last two decades have witnessed a diversity of nanoplasmonic systems with outstanding sensitivity, the implementation of LSPR sensing into a real analytical device is only at its infancy. In this context, we present here our latest advances in the optical, label free detection of biomolecules based on gold nanoantennas integrated into a state-of-the-art microfluidic platform. We first demonstrate the capability of our platform to detect low concentrations (<1ng/ml) of protein cancer markers in human serum with low unspecific binding and high repeatability. In a second step we present a novel design that enables to simultaneously determine the absolute concentration of four different target molecules from an unknown sample. The system is validated in the context of breast cancer, as a strategy to assess the risk for brain metastasis. In the final part of the paper we discuss the use of LSPR sensing for the detection of other targets, including DNA and exosomes. Our research demonstrates the high potential of gold nanoparticles for the detection of different biomarkers in real biological samples and thus gets us closer to future LSPR-based point-of-care devices.

Carbon nanotube-sensor-integrated microfluidic platform for real-time chemical concentration detection.

PubMed

Yang, Li; Li, Minglin; Qu, Yanli; Dong, Zaili; Li, Wen J

2009-09-01

This paper presents the development of a chemical sensor employing electronic-grade carbon nanotubes (EG-CNTs) as the active sensing element for sodium hypochlorite detection. The sensor, integrated in a PDMS-glass microfluidic chamber, was fabricated by bulk aligning of EG-CNTs between gold microelectrode pairs using dielectrophoretic technique. Upon exposure to sodium hypochlorite solution, the characteristics of the carbon nanotube chemical sensor were investigated at room temperature under constant current mode. The sensor exhibited responsivity, which fits a linear logarithmic dependence on concentration in the range of 1/32 to 8 ppm, a detection limit lower than 5 ppb, while saturating at 16 ppm. The typical response time of the sensor at room temperature is on the order of minutes and the recovery time is a few hours. In particular, the sensor showed an obvious sensitivity to the volume of detected solution. It was found that the activation power of the sensor was extremely low, i.e. in the range of nanowatts. These results indicate great potential of EG-CNT for advanced nanosensors with superior sensitivity, ultra-low power consumption, and less fabrication complexity.

Ecological Interventionist Causal Models in Psychosis: Targeting Psychological Mechanisms in Daily Life

PubMed Central

Reininghaus, Ulrich; Depp, Colin A.; Myin-Germeys, Inez

2016-01-01

Integrated models of psychotic disorders have posited a number of putative psychological mechanisms that may contribute to the development of psychotic symptoms, but it is only recently that a modest amount of experience sampling research has provided evidence on their role in daily life, outside the research laboratory. A number of methodological challenges remain in evaluating specificity of potential causal links between a given psychological mechanism and psychosis outcomes in a systematic fashion, capitalizing on longitudinal data to investigate temporal ordering. In this article, we argue for testing ecological interventionist causal models that draw on real world and real-time delivered, ecological momentary interventions for generating evidence on several causal criteria (association, time order, and direction/sole plausibility) under real-world conditions, while maximizing generalizability to social contexts and experiences in heterogeneous populations. Specifically, this approach tests whether ecological momentary interventions can (1) modify a putative mechanism and (2) produce changes in the mechanism that lead to sustainable changes in intended psychosis outcomes in individuals’ daily lives. Future research using this approach will provide translational evidence on the active ingredients of mobile health and in-person interventions that promote sustained effectiveness of ecological momentary interventions and, thereby, contribute to ongoing efforts that seek to enhance effectiveness of psychological interventions under real-world conditions. PMID:26707864

Coarse Resolution SAR Imagery to Support Flood Inundation Models in Near Real Time

NASA Astrophysics Data System (ADS)

Di Baldassarre, Giuliano; Schumann, Guy; Brandimarte, Luigia; Bates, Paul

2009-11-01

In recent years, the availability of new emerging data (e.g. remote sensing, intelligent wireless sensors, etc) has led to a sudden shift from a data-sparse to a data-rich environment for hydrological and hydraulic modelling. Furthermore, the increased socioeconomic relevance of river flood studies has motivated the development of complex methodologies for the simulation of the hydraulic behaviour of river systems. In this context, this study aims at assessing the capability of coarse resolution SAR (Synthetic Aperture Radar) imagery to support and quickly validate flood inundation models in near real time. A hydraulic model of a 98km reach of the River Po (Italy), previously calibrated on a high-magnitude flood event with extensive and high quality field data, is tested using a SAR flood image, acquired and processed in near real time, during the June 2008 low-magnitude event. Specifically, the image is an acquisition by the ENVISAT-ASAR sensor in wide swath mode and has been provided through ESA (European Space Agency) Fast Registration system at no cost 24 hours after the acquisition. The study shows that the SAR image enables validation and improvement of the model in a time shorter than the flood travel time. This increases the reliability of model predictions (e.g. water elevation and inundation width along the river reach) and, consequently, assists flood management authorities in undertaking the necessary prevention activities.

Real-Time Charging Strategies for an Electric Vehicle Aggregator to Provide Ancillary Services

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

Wenzel, George; Negrete-Pincetic, Matias; Olivares, Daniel E.

Real-time charging strategies, in the context of vehicle to grid (V2G) technology, are needed to enable the use of electric vehicle (EV) fleets batteries to provide ancillary services (AS). Here, we develop tools to manage charging and discharging in a fleet to track an Automatic Generation Control (AGC) signal when aggregated. We also propose a real-time controller that considers bidirectional charging efficiency and extend it to study the effect of looking ahead when implementing Model Predictive Control (MPC). Simulations show that the controller improves tracking error as compared with benchmark scheduling algorithms, as well as regulation capacity and battery cycling.

Real-Time Charging Strategies for an Electric Vehicle Aggregator to Provide Ancillary Services

DOE PAGES

Wenzel, George; Negrete-Pincetic, Matias; Olivares, Daniel E.; ...

2017-03-13

Real-time charging strategies, in the context of vehicle to grid (V2G) technology, are needed to enable the use of electric vehicle (EV) fleets batteries to provide ancillary services (AS). Here, we develop tools to manage charging and discharging in a fleet to track an Automatic Generation Control (AGC) signal when aggregated. We also propose a real-time controller that considers bidirectional charging efficiency and extend it to study the effect of looking ahead when implementing Model Predictive Control (MPC). Simulations show that the controller improves tracking error as compared with benchmark scheduling algorithms, as well as regulation capacity and battery cycling.

An integrated and highly sensitive ultrafast acoustoelectric imaging system for biomedical applications

NASA Astrophysics Data System (ADS)

Berthon, Beatrice; Dansette, Pierre-Marc; Tanter, Mickaël; Pernot, Mathieu; Provost, Jean

2017-07-01

Direct imaging of the electrical activation of the heart is crucial to better understand and diagnose diseases linked to arrhythmias. This work presents an ultrafast acoustoelectric imaging (UAI) system for direct and non-invasive ultrafast mapping of propagating current densities using the acoustoelectric effect. Acoustoelectric imaging is based on the acoustoelectric effect, the modulation of the medium’s electrical impedance by a propagating ultrasonic wave. UAI triggers this effect with plane wave emissions to image current densities. An ultrasound research platform was fitted with electrodes connected to high common-mode rejection ratio amplifiers and sampled by up to 128 independent channels. The sequences developed allow for both real-time display of acoustoelectric maps and long ultrafast acquisition with fast off-line processing. The system was evaluated by injecting controlled currents into a saline pool via copper wire electrodes. Sensitivity to low current and low acoustic pressure were measured independently. Contrast and spatial resolution were measured for varying numbers of plane waves and compared to line per line acoustoelectric imaging with focused beams at equivalent peak pressure. Temporal resolution was assessed by measuring time-varying current densities associated with sinusoidal currents. Complex intensity distributions were also imaged in 3D. Electrical current densities were detected for injected currents as low as 0.56 mA. UAI outperformed conventional focused acoustoelectric imaging in terms of contrast and spatial resolution when using 3 and 13 plane waves or more, respectively. Neighboring sinusoidal currents with opposed phases were accurately imaged and separated. Time-varying currents were mapped and their frequency accurately measured for imaging frame rates up to 500 Hz. Finally, a 3D image of a complex intensity distribution was obtained. The results demonstrated the high sensitivity of the UAI system proposed. The plane wave based approach provides a highly flexible trade-off between frame rate, resolution and contrast. In conclusion, the UAI system shows promise for non-invasive, direct and accurate real-time imaging of electrical activation in vivo.

Classification of Physical Activity: Information to Artificial Pancreas Control Systems in Real Time.

PubMed

Turksoy, Kamuran; Paulino, Thiago Marques Luz; Zaharieva, Dessi P; Yavelberg, Loren; Jamnik, Veronica; Riddell, Michael C; Cinar, Ali

2015-10-06

Physical activity has a wide range of effects on glucose concentrations in type 1 diabetes (T1D) depending on the type (ie, aerobic, anaerobic, mixed) and duration of activity performed. This variability in glucose responses to physical activity makes the development of artificial pancreas (AP) systems challenging. Automatic detection of exercise type and intensity, and its classification as aerobic or anaerobic would provide valuable information to AP control algorithms. This can be achieved by using a multivariable AP approach where biometric variables are measured and reported to the AP at high frequency. We developed a classification system that identifies, in real time, the exercise intensity and its reliance on aerobic or anaerobic metabolism and tested this approach using clinical data collected from 5 persons with T1D and 3 individuals without T1D in a controlled laboratory setting using a variety of common types of physical activity. The classifier had an average sensitivity of 98.7% for physiological data collected over a range of exercise modalities and intensities in these subjects. The classifier will be added as a new module to the integrated multivariable adaptive AP system to enable the detection of aerobic and anaerobic exercise for enhancing the accuracy of insulin infusion strategies during and after exercise. © 2015 Diabetes Technology Society.

Graphical user interface concepts for tactical augmented reality

NASA Astrophysics Data System (ADS)

Argenta, Chris; Murphy, Anne; Hinton, Jeremy; Cook, James; Sherrill, Todd; Snarski, Steve

2010-04-01

Applied Research Associates and BAE Systems are working together to develop a wearable augmented reality system under the DARPA ULTRA-Vis program†. Our approach to achieve the objectives of ULTRAVis, called iLeader, incorporates a full color 40° field of view (FOV) see-thru holographic waveguide integrated with sensors for full position and head tracking to provide an unobtrusive information system for operational maneuvers. iLeader will enable warfighters to mark-up the 3D battle-space with symbologic identification of graphical control measures, friendly force positions and enemy/target locations. Our augmented reality display provides dynamic real-time painting of symbols on real objects, a pose-sensitive 360° representation of relevant object positions, and visual feedback for a variety of system activities. The iLeader user interface and situational awareness graphical representations are highly intuitive, nondisruptive, and always tactically relevant. We used best human-factors practices, system engineering expertise, and cognitive task analysis to design effective strategies for presenting real-time situational awareness to the military user without distorting their natural senses and perception. We present requirements identified for presenting information within a see-through display in combat environments, challenges in designing suitable visualization capabilities, and solutions that enable us to bring real-time iconic command and control to the tactical user community.

Trace-Level Volatile Quantitation by Direct Analysis in Real Time Mass Spectrometry following Headspace Extraction: Optimization and Validation in Grapes.

PubMed

Jastrzembski, Jillian A; Bee, Madeleine Y; Sacks, Gavin L

2017-10-25

Ambient ionization mass spectrometric (AI-MS) techniques like direct analysis in real time (DART) offer the potential for rapid quantitative analyses of trace volatiles in food matrices, but performance is generally limited by the lack of preconcentration and extraction steps. The sensitivity and selectivity of AI-MS approaches can be improved through solid-phase microextraction (SPME) with appropriate thin-film geometries, for example, solid-phase mesh-enhanced sorption from headspace (SPMESH). This work improves the SPMESH-DART-MS approach for use in food analyses and validates the approach for trace volatile analysis for two compounds in real samples (grape macerates). SPMESH units prepared with different sorbent coatings were evaluated for their ability to extract a range of odor-active volatiles, with poly(dimethylsiloxane)/divinylbenzene giving the most satisfactory results. In combination with high-resolution mass spectrometry (HRMS), detection limits for SPMESH-DART-MS under 4 ng/L in less than 30 s acquisition times could be achieved for some volatiles [3-isobutyl-2-methoxypyrazine (IBMP) and β-damascenone]. A comparison of SPMESH-DART-MS and SPME-GC-MS quantitation of linalool and IBMP demonstrates excellent agreement between the two methods for real grape samples (r 2 ≥ 0.90), although linalool measurements appeared to also include isobaric interference.

An innovative tool for moving malaria PCR detection of parasite reservoir into the field

PubMed Central

2013-01-01

Background To achieve the goal of malaria elimination in low transmission areas such as in Cambodia, new, inexpensive, high-throughput diagnostic tools for identifying very low parasite densities in asymptomatic carriers are required. This will enable a switch from passive to active malaria case detection in the field. Methods DNA extraction and real-time PCR assays were implemented in an “in-house” designed mobile laboratory allowing implementation of a robust, sensitive and rapid malaria diagnostic strategy in the field. This tool was employed in a survey organized in the context of the MalaResT project (NCT01663831). Results The real-time PCR screening and species identification assays were performed in the mobile laboratory between October and November 2012, in Rattanakiri Province, to screen approximately 5,000 individuals in less than four weeks and treat parasite carriers within 24–48 hours after sample collection. An average of 240 clinical samples (and 40 quality control samples) was tested every day, six/seven days per week. Some 97.7% of the results were available <24 hours after the collection. A total of 4.9% were positive for malaria. Plasmodium vivax was present in 61.1% of the positive samples, Plasmodium falciparum in 45.9%, Plasmodium malariae in 7.0% and Plasmodium ovale in 2.0%. Conclusions The operational success of this diagnostic set-up proved that molecular testing and subsequent treatment is logistically achievable in field settings. This will allow the detection of clusters of asymptomatic carriers and to provide useful epidemiological information. Fast results will be of great help for staff in the field to track and treat asymptomatic parasitaemic cases. The concept of the mobile laboratory could be extended to other countries for the molecular detection of malaria or other pathogens, or to culture vivax parasites, which does not support long-time delay between sample collection and culture. PMID:24206649

Near Real-Time Comprehension Classification with Artificial Neural Networks: Decoding e-Learner Non-Verbal Behavior

ERIC Educational Resources Information Center

Holmes, Mike; Latham, Annabel; Crockett, Keeley; O'Shea, James D.

2018-01-01

Comprehension is an important cognitive state for learning. Human tutors recognize comprehension and non-comprehension states by interpreting learner non-verbal behavior (NVB). Experienced tutors adapt pedagogy, materials, and instruction to provide additional learning scaffold in the context of perceived learner comprehension. Near real-time…

Comparison of a real-time PCR method with a culture method for the detection of Salmonella enterica serotype enteritidis in naturally contaminated environmental samples from integrated poultry houses.

PubMed

Lungu, Bwalya; Waltman, W Douglas; Berghaus, Roy D; Hofacre, Charles L

2012-04-01

Conventional culture methods have traditionally been considered the "gold standard" for the isolation and identification of foodborne bacterial pathogens. However, culture methods are labor-intensive and time-consuming. A Salmonella enterica serotype Enteritidis-specific real-time PCR assay that recently received interim approval by the National Poultry Improvement Plan for the detection of Salmonella Enteritidis was evaluated against a culture method that had also received interim National Poultry Improvement Plan approval for the analysis of environmental samples from integrated poultry houses. The method was validated with 422 field samples collected by either the boot sock or drag swab method. The samples were cultured by selective enrichment in tetrathionate broth followed by transfer onto a modified semisolid Rappaport-Vassiliadis medium and then plating onto brilliant green with novobiocin and xylose lysine brilliant Tergitol 4 plates. One-milliliter aliquots of the selective enrichment broths from each sample were collected for DNA extraction by the commercial PrepSEQ nucleic acid extraction assay and analysis by the Salmonella Enteritidis-specific real-time PCR assay. The real-time PCR assay detected no significant differences between the boot sock and drag swab samples. In contrast, the culture method detected a significantly higher number of positive samples from boot socks. The diagnostic sensitivity of the real-time PCR assay for the field samples was significantly higher than that of the culture method. The kappa value obtained was 0.46, indicating moderate agreement between the real-time PCR assay and the culture method. In addition, the real-time PCR method had a turnaround time of 2 days compared with 4 to 8 days for the culture method. The higher sensitivity as well as the reduction in time and labor makes this real-time PCR assay an excellent alternative to conventional culture methods for diagnostic purposes, surveillance, and research studies to improve food safety.

Assessing the interactivity and prescriptiveness of faculty professional development workshops: The real-time professional development observation tool

NASA Astrophysics Data System (ADS)

Olmstead, Alice; Turpen, Chandra

2016-12-01

Professional development workshops are one of the primary mechanisms used to help faculty improve their teaching, and draw in many STEM instructors every year. Although workshops serve a critical role in changing instructional practices within our community, we rarely assess workshops through careful consideration of how they engage faculty. Initial evidence suggests that workshop leaders often overlook central tenets of education research that are well established in classroom contexts, such as the role of interactivity in enabling student learning [S. Freeman et al., Proc. Natl. Acad. Sci. U.S.A. 111, 8410 (2014)]. As such, there is a need to develop more robust, evidence-based models of how best to support faculty learning in professional development contexts, and to actively support workshop leaders in relating their design decisions to familiar ideas from other educational contexts. In response to these needs, we have developed an observation tool, the real-time professional development observation tool (R-PDOT), to document the form and focus of faculty engagement during workshops. In this paper, we describe the motivation and methodological considerations behind the development of the R-PDOT, justify our decisions to highlight particular aspects of workshop sessions, and demonstrate how the R-PDOT can be used to analyze three sessions from the Physics and Astronomy New Faculty Workshop. We also justify the accessibility and potential utility of the R-PDOT output as a reflective tool using preliminary data from interviews with workshop leaders, and consider the roles the R-PDOT could play in supporting future research on faculty professional development.

Real-time two-dimensional temperature imaging using ultrasound.

PubMed

Liu, Dalong; Ebbini, Emad S

2009-01-01

We present a system for real-time 2D imaging of temperature change in tissue media using pulse-echo ultrasound. The frontend of the system is a SonixRP ultrasound scanner with a research interface giving us the capability of controlling the beam sequence and accessing radio frequency (RF) data in real-time. The beamformed RF data is streamlined to the backend of the system, where the data is processed using a two-dimensional temperature estimation algorithm running in the graphics processing unit (GPU). The estimated temperature is displayed in real-time providing feedback that can be used for real-time control of the heating source. Currently we have verified our system with elastography tissue mimicking phantom and in vitro porcine heart tissue, excellent repeatability and sensitivity were demonstrated.

Real-time UNIX in HEP data acquisition

NASA Astrophysics Data System (ADS)

Buono, S.; Gaponenko, I.; Jones, R.; Mapelli, L.; Mornacchi, G.; Prigent, D.; Sanchez-Corral, E.; Skiadelli, M.; Toppers, A.; Duval, P. Y.; Ferrato, D.; Le Van Suu, A.; Qian, Z.; Rondot, C.; Ambrosini, G.; Fumagalli, G.; Aguer, M.; Huet, M.

1994-12-01

Today's experimentation in high energy physics is characterized by an increasing need for sensitivity to rare phenomena and complex physics signatures, which require the use of huge and sophisticated detectors and consequently a high performance readout and data acquisition. Multi-level triggering, hierarchical data collection and an always increasing amount of processing power, distributed throughout the data acquisition layers, will impose a number of features on the software environment, especially the need for a high level of standardization. Real-time UNIX seems, today, the best solution for the platform independence, operating system interface standards and real-time features necessary for data acquisition in HEP experiments. We present the results of the evaluation, in a realistic application environment, of a Real-Time UNIX operating system: the EP/LX real-time UNIX system.

Temperament trait of sensory processing sensitivity moderates cultural differences in neural response.

PubMed

Aron, Arthur; Ketay, Sarah; Hedden, Trey; Aron, Elaine N; Rose Markus, Hazel; Gabrieli, John D E

2010-06-01

This study focused on a possible temperament-by-culture interaction. Specifically, it explored whether a basic temperament/personality trait (sensory processing sensitivity; SPS), perhaps having a genetic component, might moderate a previously established cultural difference in neural responses when making context-dependent vs context-independent judgments of simple visual stimuli. SPS has been hypothesized to underlie what has been called inhibitedness or reactivity in infants, introversion in adults, and reactivity or responsivness in diverse animal species. Some biologists view the trait as one of two innate strategies-observing carefully before acting vs being first to act. Thus the central characteristic of SPS is hypothesized to be a deep processing of information. Here, 10 European-Americans and 10 East Asians underwent functional magnetic resonance imaging while performing simple visuospatial tasks emphasizing judgments that were either context independent (typically easier for Americans) or context dependent (typically easier for Asians). As reported elsewhere, each group exhibited greater activation for the culturally non-preferred task in frontal and parietal regions associated with greater effort in attention and working memory. However, further analyses, reported here for the first time, provided preliminary support for moderation by SPS. Consistent with the careful-processing theory, high-SPS individuals showed little cultural difference; low-SPS, strong culture differences.

Temperament trait of sensory processing sensitivity moderates cultural differences in neural response

PubMed Central

Ketay, Sarah; Hedden, Trey; Aron, Elaine N.; Rose Markus, Hazel; Gabrieli, John D. E.

2010-01-01

This study focused on a possible temperament-by-culture interaction. Specifically, it explored whether a basic temperament/personality trait (sensory processing sensitivity; SPS), perhaps having a genetic component, might moderate a previously established cultural difference in neural responses when making context-dependent vs context-independent judgments of simple visual stimuli. SPS has been hypothesized to underlie what has been called inhibitedness or reactivity in infants, introversion in adults, and reactivity or responsivness in diverse animal species. Some biologists view the trait as one of two innate strategies—observing carefully before acting vs being first to act. Thus the central characteristic of SPS is hypothesized to be a deep processing of information. Here, 10 European-Americans and 10 East Asians underwent functional magnetic resonance imaging while performing simple visuospatial tasks emphasizing judgments that were either context independent (typically easier for Americans) or context dependent (typically easier for Asians). As reported elsewhere, each group exhibited greater activation for the culturally non-preferred task in frontal and parietal regions associated with greater effort in attention and working memory. However, further analyses, reported here for the first time, provided preliminary support for moderation by SPS. Consistent with the careful-processing theory, high-SPS individuals showed little cultural difference; low-SPS, strong culture differences. PMID:20388694

Autonomous indoor wayfinding for individuals with cognitive impairments

PubMed Central

2010-01-01

Background A challenge to individuals with cognitive impairments in wayfinding is how to remain oriented, recall routines, and travel in unfamiliar areas in a way relying on limited cognitive capacity. While people without disabilities often use maps or written directions as navigation tools or for remaining oriented, this cognitively-impaired population is very sensitive to issues of abstraction (e.g. icons on maps or signage) and presents the designer with a challenge to tailor navigation information specific to each user and context. Methods This paper describes an approach to providing distributed cognition support of travel guidance for persons with cognitive disabilities. A solution is proposed based on passive near-field RFID tags and scanning PDAs. A prototype is built and tested in field experiments with real subjects. The unique strength of the system is the ability to provide unique-to-the-user prompts that are triggered by context. The key to the approach is to spread the context awareness across the system, with the context being flagged by the RFID tags and the appropriate response being evoked by displaying the appropriate path guidance images indexed by the intersection of specific end-user and context ID embedded in RFID tags. Results We found that passive RFIDs generally served as good context for triggering navigation prompts, although individual differences in effectiveness varied. The results of controlled experiments provided more evidence with regard to applicabilities of the proposed autonomous indoor wayfinding method. Conclusions Our findings suggest that the ability to adapt indoor wayfinding devices for appropriate timing of directions and standing orientation will be particularly important. PMID:20840786

Comparison of Real-Time PCR and Conventional Biochemical Methods for Identification of Staphylococcus lugdunensis▿

PubMed Central

Pinsky, Benjamin A.; Samson, Divinia; Ghafghaichi, Laleh; Baron, Ellen J.; Banaei, Niaz

2009-01-01

Staphylococcus lugdunensis is an aggressive, virulent member of the coagulase-negative staphylococci (CoNS) that is responsible for severe, rapidly progressive skin and soft tissue infections and native valve endocarditis. To facilitate prompt identification and appropriate therapy, we describe here a rapid and robust multiplex real-time PCR assay that is able to definitively distinguish S. lugdunensis from other staphylococci. Using melting curve analysis, the assay also identifies Staphylococcus aureus and CoNS other than S. lugdunensis and determines MecA-dependent resistance to methicillin (meticillin). When applied to a panel of well-characterized staphylococcal reference strains, as well as 165 clinical isolates previously identified by conventional methods, the assay was both sensitive and specific for S. lugdunensis, correctly identifying the reference strain and all 47 S. lugdunensis isolates without inappropriate amplification of other staphylococci. Furthermore, rapid biochemical identification using the WEE-TAB system to detect ornithine decarboxylase activity was found to be unsuitable as an alternative to PCR identification, displaying just 31% sensitivity and 77% specificity when tested on a subset (90 isolates) of the clinical strains. We therefore propose that this simple, accurate PCR approach will allow for the routine and timely identification of S. lugdunensis in the clinical microbiology laboratory. PMID:19741081

15 CFR Supplement No. 7 to Part 774 - Very Sensitive List

Code of Federal Regulations, 2014 CFR

2014-01-01

... designed” for real time application with towed acoustic hydrophone arrays, having “user accessible....2.f—Processing equipment, “specially designed” for real time application with bottom or bay cable...” “specially designed” for a defense article not on the USML or a commodity controlled by a “600 series” ECCN...

Identification and evaluation of reliable reference genes for quantitative real-time PCR analysis in tea plant (Camellia sinensis (L.) O. Kuntze)

USDA-ARS?s Scientific Manuscript database

Quantitative real-time polymerase chain reaction (qRT-PCR) is a commonly used technique for measuring gene expression levels due to its simplicity, specificity, and sensitivity. Reliable reference selection for the accurate quantification of gene expression under various experimental conditions is a...

Development of a real-time RT-PCR assay for a novel influenza A (H1N1) virus.

PubMed

Jiang, Tao; Kang, Xiaoping; Deng, Yongqiang; Zhao, Hui; Li, Xiaofeng; Yu, Xuedong; Yu, Man; Qin, Ede; Zhu, Qingyu; Yang, Yinhui; Qin, Chengfeng

2010-02-01

A pandemic caused by a novel influenza A virus (H1N1) poses a serious public health threat. In this study, a real-time reverse transcriptase PCR (RT-PCR) assay based on the hemagglutinin gene was developed that discriminates the novel H1N1 from swine influenza virus, seasonal H1N1/H3N2 virus and the highly pathogenic H5N1 avian influenza virus. The sensitivity of this assay was 0.2 50% tissue culture infective dose of virus and 200 copies of in vitro-transcribed target RNA. Three hundred and forty-eight clinical specimens from suspected H1N1 patients were tested using this assay, and forty-two (12.07%) were found to be positive. Tests using the real-time PCR assay recommended by WHO and virus isolation gave identical results. This sensitive and specific real-time RT-PCR assay will contribute to the early diagnosis and control of the emerging H1N1 influenza pandemic. 2009 Elsevier B.V. All rights reserved.

Application of Fiber Optic ATR-FTIR Methods for In Situ Characterization of Protein Delivery Systems in Real Time

PubMed Central

McFearin, Cathryn L.; Sankaranarayanan, Jagadis; Almutairi, Adah

2011-01-01

Real Time Characterization of Protein Delivery Systems A fiber optic coupled ATR-FTIR spectroscopy technique was applied to the study of two different therapeutic delivery systems, acid degradable hydrogels and nanoparticles. Real time exponential release of a model protein, human serum albumin (HSA), was observed from two different polymeric hydrogels formulated with a pH sensitive crosslinker. Spectroscopic examination of nanoparticles formulated with an acid degradable polymer shell and encapsulated HSA exhibited vibrational signatures characteristic of both particle and payload when exposed to lowered pH conditions demonstrating the ability of this methodology to simultaneously measure phenomena arising from a system with a mixture of components. In addition, thorough characterization of these pH sensitive delivery vehicles without encapsulated protein was also accomplished in order to separate the effects of the payload during degradation. By providing in situ, real time detection in combination with the ability to specifically identify different components in a mixture without involved sample preparation and minimal sample disturbance, the versatility and suitability of this type of experiment for research in the pharmaceutical field is demonstrated. PMID:21476582

Listeriolysin O Membrane Damaging Activity Involves Arc Formation and Lineaction -- Implication for Listeria monocytogenes Escape from Phagocytic Vacuole

PubMed Central

Ruan, Yi; Rezelj, Saša; Bedina Zavec, Apolonija; Anderluh, Gregor; Scheuring, Simon

2016-01-01

Listeriolysin-O (LLO) plays a crucial role during infection by Listeria monocytogenes. It enables escape of bacteria from phagocytic vacuole, which is the basis for its spread to other cells and tissues. It is not clear how LLO acts at phagosomal membranes to allow bacterial escape. The mechanism of action of LLO remains poorly understood, probably due to unavailability of suitable experimental tools that could monitor LLO membrane disruptive activity in real time. Here, we used high-speed atomic force microscopy (HS-AFM) featuring high spatio-temporal resolution on model membranes and optical microscopy on giant unilamellar vesicles (GUVs) to investigate LLO activity. We analyze the assembly kinetics of toxin oligomers, the prepore-to-pore transition dynamics and the membrane disruption in real time. We reveal that LLO toxin efficiency and mode of action as a membrane-disrupting agent varies strongly depending on the membrane cholesterol concentration and the environmental pH. We discovered that LLO is able to form arc pores as well as damage lipid membranes as a lineactant, and this leads to large-scale membrane defects. These results altogether provide a mechanistic basis of how large-scale membrane disruption leads to release of Listeria from the phagocytic vacuole in the cellular context. PMID:27104344

Models of emergency departments for reducing patient waiting times.

PubMed

Laskowski, Marek; McLeod, Robert D; Friesen, Marcia R; Podaima, Blake W; Alfa, Attahiru S

2009-07-02

In this paper, we apply both agent-based models and queuing models to investigate patient access and patient flow through emergency departments. The objective of this work is to gain insights into the comparative contributions and limitations of these complementary techniques, in their ability to contribute empirical input into healthcare policy and practice guidelines. The models were developed independently, with a view to compare their suitability to emergency department simulation. The current models implement relatively simple general scenarios, and rely on a combination of simulated and real data to simulate patient flow in a single emergency department or in multiple interacting emergency departments. In addition, several concepts from telecommunications engineering are translated into this modeling context. The framework of multiple-priority queue systems and the genetic programming paradigm of evolutionary machine learning are applied as a means of forecasting patient wait times and as a means of evolving healthcare policy, respectively. The models' utility lies in their ability to provide qualitative insights into the relative sensitivities and impacts of model input parameters, to illuminate scenarios worthy of more complex investigation, and to iteratively validate the models as they continue to be refined and extended. The paper discusses future efforts to refine, extend, and validate the models with more data and real data relative to physical (spatial-topographical) and social inputs (staffing, patient care models, etc.). Real data obtained through proximity location and tracking system technologies is one example discussed.

Models of Emergency Departments for Reducing Patient Waiting Times

PubMed Central

Laskowski, Marek; McLeod, Robert D.; Friesen, Marcia R.; Podaima, Blake W.; Alfa, Attahiru S.

2009-01-01

In this paper, we apply both agent-based models and queuing models to investigate patient access and patient flow through emergency departments. The objective of this work is to gain insights into the comparative contributions and limitations of these complementary techniques, in their ability to contribute empirical input into healthcare policy and practice guidelines. The models were developed independently, with a view to compare their suitability to emergency department simulation. The current models implement relatively simple general scenarios, and rely on a combination of simulated and real data to simulate patient flow in a single emergency department or in multiple interacting emergency departments. In addition, several concepts from telecommunications engineering are translated into this modeling context. The framework of multiple-priority queue systems and the genetic programming paradigm of evolutionary machine learning are applied as a means of forecasting patient wait times and as a means of evolving healthcare policy, respectively. The models' utility lies in their ability to provide qualitative insights into the relative sensitivities and impacts of model input parameters, to illuminate scenarios worthy of more complex investigation, and to iteratively validate the models as they continue to be refined and extended. The paper discusses future efforts to refine, extend, and validate the models with more data and real data relative to physical (spatial–topographical) and social inputs (staffing, patient care models, etc.). Real data obtained through proximity location and tracking system technologies is one example discussed. PMID:19572015

Engineered Context-Sensitive Agonism: Tissue-Selective Drug Signaling through a G Protein-Coupled Receptor.

PubMed

Seemann, Wiebke K; Wenzel, Daniela; Schrage, Ramona; Etscheid, Justine; Bödefeld, Theresa; Bartol, Anna; Warnken, Mareille; Sasse, Philipp; Klöckner, Jessica; Holzgrabe, Ulrike; DeAmici, Marco; Schlicker, Eberhard; Racké, Kurt; Kostenis, Evi; Meyer, Rainer; Fleischmann, Bernd K; Mohr, Klaus

2017-02-01

Drug discovery strives for selective ligands to achieve targeted modulation of tissue function. Here we introduce engineered context-sensitive agonism as a postreceptor mechanism for tissue-selective drug action through a G protein-coupled receptor. Acetylcholine M 2 -receptor activation is known to mediate, among other actions, potentially dangerous slowing of the heart rate. This unwanted side effect is one of the main reasons that limit clinical application of muscarinic agonists. Herein we show that dualsteric (orthosteric/allosteric) agonists induce less cardiac depression ex vivo and in vivo than conventional full agonists. Exploration of the underlying mechanism in living cells employing cellular dynamic mass redistribution identified context-sensitive agonism of these dualsteric agonists. They translate elevation of intracellular cAMP into a switch from full to partial agonism. Designed context-sensitive agonism opens an avenue toward postreceptor pharmacologic selectivity, which even works in target tissues operated by the same subtype of pharmacologic receptor. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

Activity analysis: contributions to the innovation of projects for aircrafts cabins.

PubMed

Rossi, N T; Greghi, F M; Menegon, L N; Souza, G B J

2012-01-01

This article presents results obtained from some ergonomics intervention in the project for the conception of aircraft's cabins. The study's aim is to analyze the contribution of the method adopted in the passengers' activities analysis in reference situations, real-use situations in aircraft's cabins, applied to analyze typical activities performed by people in their own environment. Within this perspective, the study shows two analyses which highlight the use of electronic device. The first analysis has been registered through a shooting filming in a real commercial flight. In the second one, the use is developed within the domestic environment. The same method has been applied in both contexts and it is based on activity analysis. Starting with the filming activity, postures and actions analysis, self-confrontation interviews, action course reconstruction and elaboration of postures envelopes. The results point out that the developed method might be applied to different contexts, evincing different ways of space occupation to meet human personal needs while performing an activity, which can help us with the anticipation of the users' needs, as well as indicate some innovation possibilities.

Design and development of a highly sensitive, field portable plasma source instrument for on-line liquid stream monitoring and real-time sample analysis

NASA Astrophysics Data System (ADS)

Duan, Yixiang; Su, Yongxuan; Jin, Zhe; Abeln, Stephen P.

2000-03-01

The development of a highly sensitive, field portable, low-powered instrument for on-site, real-time liquid waste stream monitoring is described in this article. A series of factors such as system sensitivity and portability, plasma source, sample introduction, desolvation system, power supply, and the instrument configuration, were carefully considered in the design of the portable instrument. A newly designed, miniature, modified microwave plasma source was selected as the emission source for spectroscopy measurement, and an integrated small spectrometer with a charge-coupled device detector was installed for signal processing and detection. An innovative beam collection system with optical fibers was designed and used for emission signal collection. Microwave plasma can be sustained with various gases at relatively low power, and it possesses high detection capabilities for both metal and nonmetal pollutants, making it desirable to use for on-site, real-time, liquid waste stream monitoring. An effective in situ sampling system was coupled with a high efficiency desolvation device for direct-sampling liquid samples into the plasma. A portable computer control system is used for data processing. The new, integrated instrument can be easily used for on-site, real-time monitoring in the field. The system possesses a series of advantages, including high sensitivity for metal and nonmetal elements; in situ sampling; compact structure; low cost; and ease of operation and handling. These advantages will significantly overcome the limitations of previous monitoring techniques and make great contributions to environmental restoration and monitoring.

A Portable Array-Type Optical Fiber Sensing Instrument for Real-Time Gas Detection

PubMed Central

Hung, San-Shan; Chang, Hsing-Cheng; Chang, I-Nan

2016-01-01

A novel optical fiber array-type of sensing instrument with temperature compensation for real-time detection was developed to measure oxygen, carbon dioxide, and ammonia simultaneously. The proposed instrument is multi-sensing array integrated with real-time measurement module for portable applications. The sensing optical fibers were etched and polished before coating to increase sensitivities. The ammonia and temperature sensors were each composed of a dye-coated single-mode fiber with constructing a fiber Bragg grating and a long-period filter grating for detecting light intensity. Both carbon dioxide and oxygen sensing structures use multimode fibers where 1-hydroxy-3,6,8-pyrene trisulfonic acid trisodium salt is coated for carbon dioxide sensing and Tris(2,2′-bipyridyl) dichlororuthenium(II) hexahydrate and Tris(bipyridine)ruthenium(II) chloride are coated for oxygen sensing. Gas-induced fluorescent light intensity variation was applied to detect gas concentration. The portable gas sensing array was set up by integrating with photo-electronic measurement modules and a human-machine interface to detect gases in real time. The measured data have been processed using piecewise-linear method. The sensitivity of the oxygen sensor were 1.54%/V and 9.62%/V for concentrations less than 1.5% and for concentrations between 1.5% and 6%, respectively. The sensitivity of the carbon dioxide sensor were 8.33%/V and 9.62%/V for concentrations less than 2% and for concentrations between 2% and 5%, respectively. For the ammonia sensor, the sensitivity was 27.78%/V, while ammonia concentration was less than 2%. PMID:27941636

A Portable Array-Type Optical Fiber Sensing Instrument for Real-Time Gas Detection.

PubMed

Hung, San-Shan; Chang, Hsing-Cheng; Chang, I-Nan

2016-12-08

A novel optical fiber array-type of sensing instrument with temperature compensation for real-time detection was developed to measure oxygen, carbon dioxide, and ammonia simultaneously. The proposed instrument is multi-sensing array integrated with real-time measurement module for portable applications. The sensing optical fibers were etched and polished before coating to increase sensitivities. The ammonia and temperature sensors were each composed of a dye-coated single-mode fiber with constructing a fiber Bragg grating and a long-period filter grating for detecting light intensity. Both carbon dioxide and oxygen sensing structures use multimode fibers where 1-hydroxy-3,6,8-pyrene trisulfonic acid trisodium salt is coated for carbon dioxide sensing and Tris(2,2'-bipyridyl) dichlororuthenium(II) hexahydrate and Tris(bipyridine)ruthenium(II) chloride are coated for oxygen sensing. Gas-induced fluorescent light intensity variation was applied to detect gas concentration. The portable gas sensing array was set up by integrating with photo-electronic measurement modules and a human-machine interface to detect gases in real time. The measured data have been processed using piecewise-linear method. The sensitivity of the oxygen sensor were 1.54%/V and 9.62%/V for concentrations less than 1.5% and for concentrations between 1.5% and 6%, respectively. The sensitivity of the carbon dioxide sensor were 8.33%/V and 9.62%/V for concentrations less than 2% and for concentrations between 2% and 5%, respectively. For the ammonia sensor, the sensitivity was 27.78%/V, while ammonia concentration was less than 2%.

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

Eto, Joseph H.; Parashar, Manu; Lewis, Nancy Jo

The Real Time System Operations (RTSO) 2006-2007 project focused on two parallel technical tasks: (1) Real-Time Applications of Phasors for Monitoring, Alarming and Control; and (2) Real-Time Voltage Security Assessment (RTVSA) Prototype Tool. The overall goal of the phasor applications project was to accelerate adoption and foster greater use of new, more accurate, time-synchronized phasor measurements by conducting research and prototyping applications on California ISO's phasor platform - Real-Time Dynamics Monitoring System (RTDMS) -- that provide previously unavailable information on the dynamic stability of the grid. Feasibility assessment studies were conducted on potential application of this technology for small-signal stabilitymore » monitoring, validating/improving existing stability nomograms, conducting frequency response analysis, and obtaining real-time sensitivity information on key metrics to assess grid stress. Based on study findings, prototype applications for real-time visualization and alarming, small-signal stability monitoring, measurement based sensitivity analysis and frequency response assessment were developed, factory- and field-tested at the California ISO and at BPA. The goal of the RTVSA project was to provide California ISO with a prototype voltage security assessment tool that runs in real time within California ISO?s new reliability and congestion management system. CERTS conducted a technical assessment of appropriate algorithms, developed a prototype incorporating state-of-art algorithms (such as the continuation power flow, direct method, boundary orbiting method, and hyperplanes) into a framework most suitable for an operations environment. Based on study findings, a functional specification was prepared, which the California ISO has since used to procure a production-quality tool that is now a part of a suite of advanced computational tools that is used by California ISO for reliability and congestion management.« less

Tritium autoradiography with thinned and back-side illuminated monolithic active pixel sensor device

NASA Astrophysics Data System (ADS)

Deptuch, G.

2005-05-01

The first autoradiographic results of the tritium ( 3H) marked source obtained with monolithic active pixel sensors are presented. The detector is a high-resolution, back-side illuminated imager, developed within the SUCIMA collaboration for low-energy (<30 keV) electrons detection. The sensitivity to these energies is obtained by thinning the detector, originally fabricated in the form of a standard VLSI chip, down to the thickness of the epitaxial layer. The detector used is the 1×10 6 pixel, thinned MIMOSA V chip. The low noise performance and thin (˜160 nm) entrance window provide the sensitivity of the device to energies as low as ˜4 keV. A polymer tritium source was parked directly atop the detector in open-air conditions. A real-time image of the source was obtained.

Real Time Search Algorithm for Observation Outliers During Monitoring Engineering Constructions

NASA Astrophysics Data System (ADS)

Latos, Dorota; Kolanowski, Bogdan; Pachelski, Wojciech; Sołoducha, Ryszard

2017-12-01

Real time monitoring of engineering structures in case of an emergency of disaster requires collection of a large amount of data to be processed by specific analytical techniques. A quick and accurate assessment of the state of the object is crucial for a probable rescue action. One of the more significant evaluation methods of large sets of data, either collected during a specified interval of time or permanently, is the time series analysis. In this paper presented is a search algorithm for those time series elements which deviate from their values expected during monitoring. Quick and proper detection of observations indicating anomalous behavior of the structure allows to take a variety of preventive actions. In the algorithm, the mathematical formulae used provide maximal sensitivity to detect even minimal changes in the object's behavior. The sensitivity analyses were conducted for the algorithm of moving average as well as for the Douglas-Peucker algorithm used in generalization of linear objects in GIS. In addition to determining the size of deviations from the average it was used the so-called Hausdorff distance. The carried out simulation and verification of laboratory survey data showed that the approach provides sufficient sensitivity for automatic real time analysis of large amount of data obtained from different and various sensors (total stations, leveling, camera, radar).

Self- and Social Regulation in Learning Contexts: An Integrative Perspective

ERIC Educational Resources Information Center

Volet, Simone; Vauras, Marja; Salonen, Pekka

2009-01-01

This article outlines the rationale for an integrative perspective of self- and social regulation in learning contexts. The role of regulatory mechanisms in self- and social regulation models is examined, leading to the view that in real time collaborative learning, individuals and social entities should be conceptualized as self-regulating and…

Bluetooth-Assisted Context-Awareness in Educational Data Networks

ERIC Educational Resources Information Center

Gonzalez-Castano, F. J.; Garcia-Reinoso, J.; Gil-Castineira, F.; Costa-Montenegro, E.; Pousada-Carballo, J. M.

2005-01-01

In this paper, we propose an auxiliary "location network", to support user-independent context-awareness in educational data networks; for example, to help visitors in a museum. We assume that, in such scenarios, there exist "service servers" that need to be aware of user location in real-time. Specifically, we propose the implementation of a…

Robust Arm and Hand Tracking by Unsupervised Context Learning

PubMed Central

Spruyt, Vincent; Ledda, Alessandro; Philips, Wilfried

2014-01-01

Hand tracking in video is an increasingly popular research field due to the rise of novel human-computer interaction methods. However, robust and real-time hand tracking in unconstrained environments remains a challenging task due to the high number of degrees of freedom and the non-rigid character of the human hand. In this paper, we propose an unsupervised method to automatically learn the context in which a hand is embedded. This context includes the arm and any other object that coherently moves along with the hand. We introduce two novel methods to incorporate this context information into a probabilistic tracking framework, and introduce a simple yet effective solution to estimate the position of the arm. Finally, we show that our method greatly increases robustness against occlusion and cluttered background, without degrading tracking performance if no contextual information is available. The proposed real-time algorithm is shown to outperform the current state-of-the-art by evaluating it on three publicly available video datasets. Furthermore, a novel dataset is created and made publicly available for the research community. PMID:25004155

Real-time computational photon-counting LiDAR

NASA Astrophysics Data System (ADS)

Edgar, Matthew; Johnson, Steven; Phillips, David; Padgett, Miles

2018-03-01

The availability of compact, low-cost, and high-speed MEMS-based spatial light modulators has generated widespread interest in alternative sampling strategies for imaging systems utilizing single-pixel detectors. The development of compressed sensing schemes for real-time computational imaging may have promising commercial applications for high-performance detectors, where the availability of focal plane arrays is expensive or otherwise limited. We discuss the research and development of a prototype light detection and ranging (LiDAR) system via direct time of flight, which utilizes a single high-sensitivity photon-counting detector and fast-timing electronics to recover millimeter accuracy three-dimensional images in real time. The development of low-cost real time computational LiDAR systems could have importance for applications in security, defense, and autonomous vehicles.

An MFC-Based Online Monitoring and Alert System for Activated Sludge Process

PubMed Central

Xu, Gui-Hua; Wang, Yun-Kun; Sheng, Guo-Ping; Mu, Yang; Yu, Han-Qing

2014-01-01

In this study, based on a simple, compact and submersible microbial fuel cell (MFC), a novel online monitoring and alert system with self-diagnosis function was established for the activated sludge (AS) process. Such a submersible MFC utilized organic substrates and oxygen in the AS reactor as the electron donor and acceptor respectively, and could provide an evaluation on the status of the AS reactor and thus give a reliable early warning of potential risks. In order to evaluate the reliability and sensitivity of this online monitoring and alert system, a series of tests were conducted to examine the response of this system to various shocks imposed on the AS reactor. The results indicate that this online monitoring and alert system was highly sensitive to the performance variations of the AS reactor. The stability, sensitivity and repeatability of this online system provide feasibility of being incorporated into current control systems of wastewater treatment plants to real-time monitor, diagnose, alert and control the AS process. PMID:25345502