WorldWideScience

Sample records for attention lapses

  1. The influence of lapses of attention on working memory capacity.

    Science.gov (United States)

    Unsworth, Nash; Robison, Matthew K

    2016-02-01

    In three experiments, the influence of lapses of attention on working memory (WM) capacity measures was examined. Participants performed various change detection tasks while also reporting whether they were focused on the current task or whether they were unfocused and mind-wandering. Participants reported that they were mind-wandering roughly 27% of the time, and when participants reported mind-wandering, their performance was worse compared to when they reported being on-task. Low WM capacity individuals reported more mind-wandering and lapses of attention than high WM capacity individuals, and mind-wandering and filtering abilities were shown to make independent contributions to capacity estimates. These results provide direct support for the notion that the ability to focus attention on-task and prevent lapses of attention is an important contributor to performance on measures of WM capacity.

  2. Age differences in attention lapses mask age differences in memory failures: a methodological note on suppression.

    Science.gov (United States)

    Cheyne, James Allan; Carriere, Jonathan S A; Smilek, Daniel

    2013-01-01

    Although objective measures of memory performance typically indicate memory declines with age, self-reported memory failures often show no relation to age. In contrast, self-reported attention failures are reliably negatively correlated with age. This contrast suggests the possibility that age-related awareness and reporting of memory failures might be masked by a concurrent decrease in attention failures, which would reduce encoding failures with age and hence reduce perceived memory failures. Self-reported problems of attention and memory were evaluated in two samples with the ages spanning eight decades. Initial analysis indicated that attention failures significantly decreased with age, whereas memory problems did not to differ across age. The association of self-reported memory failures became significantly positive, however, when residualized on attention lapses. In contrast, the correlation between attention lapses and age was modestly affected when memory failures were controlled. These results highlight the close relation of attention lapses and memory problems and, beyond the implications of individual differences in attention for memory research, suggest the advisability of assessing attention failures for a full evaluation of memory problems.

  3. The footprints of a wandering mind: Further examination of the time course of an attentional lapse.

    Science.gov (United States)

    Smallwood, Jonathan

    2011-06-01

    Recently, understanding the sequence of events that precedes an attentional lapse has become an important question in cognitive neuroscience. To examine the processes which lead to such errors, participants performed a simple go/no-go task used for measuring attentional failure. To study the role of internal distraction, the participants' tendency to daydreaming was assessed via a questionnaire. Principal components analysis (PCA) was used to decompose the response time (RT) course into the underlying components. Analysis identified three components that made up 54% of the data collected. One factor indicated the overall magnitude of the RT in a given block. This factor showed a significant negative weighting prior to an error. A second factor indicating that RT shifted from slow to fast was also identified. The parity of this factor was predictive of error for individuals high on daydreaming, indicating that errors in individuals with a rich, imaginative mental life showed a shift from slow to fast responding prior to an attentional lapse. This analysis provides further evidence that attentional lapses can result from events that took place many seconds before the mistake and that the elements of the default mode may be involved in these lapses.

  4. The contribution of attentional lapses to individual differences in visual working memory capacity.

    Science.gov (United States)

    Adam, Kirsten C S; Mance, Irida; Fukuda, Keisuke; Vogel, Edward K

    2015-08-01

    Attentional control and working memory capacity are important cognitive abilities that substantially vary between individuals. Although much is known about how attentional control and working memory capacity relate to each other and to constructs like fluid intelligence, little is known about how trial-by-trial fluctuations in attentional engagement impact trial-by-trial working memory performance. Here, we employ a novel whole-report memory task that allowed us to distinguish between varying levels of attentional engagement in humans performing a working memory task. By characterizing low-performance trials, we can distinguish between models in which working memory performance failures are caused by either (1) complete lapses of attention or (2) variations in attentional control. We found that performance failures increase with set-size and strongly predict working memory capacity. Performance variability was best modeled by an attentional control model of attention, not a lapse model. We examined neural signatures of performance failures by measuring EEG activity while participants performed the whole-report task. The number of items correctly recalled in the memory task was predicted by frontal theta power, with decreased frontal theta power associated with poor performance on the task. In addition, we found that poor performance was not explained by failures of sensory encoding; the P1/N1 response and ocular artifact rates were equivalent for high- and low-performance trials. In all, we propose that attentional lapses alone cannot explain individual differences in working memory performance. Instead, we find that graded fluctuations in attentional control better explain the trial-by-trial differences in working memory that we observe.

  5. Absent minds and absent agents: attention-lapse induced alienation of agency.

    Science.gov (United States)

    Cheyne, James Allan; Carriere, Jonathan S A; Smilek, Daniel

    2009-06-01

    We report a novel task designed to elicit transient attention-lapse induced alienation (ALIA) of agency experiences in normal participants. When attention-related action slips occur during the task, participants reported substantially decreased self control as well as a high degree of perceived agency attributed to the errant hand. In addition, participants reported being surprised by, and annoyed with, the actions of the errant hand. We argue that ALIA experiences occur because of constraints imposed by the close and precise temporal relations between intention formation and a contrary action employed in this paradigm. We note similarities between ALIA experiences and anarchic hand sign (AHS) and argue that, despite important differences, both ALIA experiences and AHS phenomenology reflect failures of executive control to intervene and cancel contrary affordance-driven habitual motor plans.

  6. The Contribution of Attentional Lapses to Individual Differences in Visual Working Memory Capacity

    OpenAIRE

    Adam, Kirsten C. S.; Mance, Irida; Fukuda, Keisuke; Vogel, Edward K.

    2015-01-01

    Attentional control and working memory capacity are important cognitive abilities that substantially vary between individuals. Although much is known about how attentional control and working memory capacity relate to each other and to constructs like fluid intelligence, little is known about how trial-by-trial fluctuations in attentional engagement impact trial-by-trial working memory performance. Here, we employ a novel whole-report memory task that allowed us to distinguish between varying...

  7. The Relation of Mild Traumatic Brain Injury to Chronic Lapses of Attention

    Science.gov (United States)

    Pontifex, Matthew B.; Broglio, Steven P.; Drollette, Eric S.; Scudder, Mark R.; Johnson, Chris R.; O'Connor, Phillip M.; Hillman, Charles H.

    2012-01-01

    We assessed the extent to which failures in sustained attention were associated with chronic mild traumatic brain injury (mTBI) deficits in cognitive control among college-age young adults with and without a history of sport-related concussion. Participants completed the ImPACT computer-based assessment and a modified flanker task. Results…

  8. Selective neuronal lapses precede human cognitive lapses following sleep deprivation.

    Science.gov (United States)

    Nir, Yuval; Andrillon, Thomas; Marmelshtein, Amit; Suthana, Nanthia; Cirelli, Chiara; Tononi, Giulio; Fried, Itzhak

    2017-12-01

    Sleep deprivation is a major source of morbidity with widespread health effects, including increased risk of hypertension, diabetes, obesity, heart attack, and stroke. Moreover, sleep deprivation brings about vehicle accidents and medical errors and is therefore an urgent topic of investigation. During sleep deprivation, homeostatic and circadian processes interact to build up sleep pressure, which results in slow behavioral performance (cognitive lapses) typically attributed to attentional thalamic and frontoparietal circuits, but the underlying mechanisms remain unclear. Recently, through study of electroencephalograms (EEGs) in humans and local field potentials (LFPs) in nonhuman primates and rodents it was found that, during sleep deprivation, regional 'sleep-like' slow and theta (slow/theta) waves co-occur with impaired behavioral performance during wakefulness. Here we used intracranial electrodes to record single-neuron activities and LFPs in human neurosurgical patients performing a face/nonface categorization psychomotor vigilance task (PVT) over multiple experimental sessions, including a session after full-night sleep deprivation. We find that, just before cognitive lapses, the selective spiking responses of individual neurons in the medial temporal lobe (MTL) are attenuated, delayed, and lengthened. These 'neuronal lapses' are evident on a trial-by-trial basis when comparing the slowest behavioral PVT reaction times to the fastest. Furthermore, during cognitive lapses, LFPs exhibit a relative local increase in slow/theta activity that is correlated with degraded single-neuron responses and with baseline theta activity. Our results show that cognitive lapses involve local state-dependent changes in neuronal activity already present in the MTL.

  9. Plasma adiabatic lapse rate

    CERN Document Server

    Amendt, Peter; Wilks, Scott

    2012-01-01

    The plasma analog of an adiabatic lapse rate (or temperature variation with height) in atmospheric physics is obtained. A new source of plasma temperature gradient in a binary ion species mixture is found that is proportional to the concentration gradient and difference in average ionization states . Application to inertial-confinement-fusion implosions indicates a potentially strong effect in plastic (CH) ablators that is not modeled with mainline (single-fluid) simulations. An associated plasma thermodiffusion coefficient is derived, and charge-state diffusion in a single-species plasma is also predicted.

  10. Lapse rate modeling

    DEFF Research Database (Denmark)

    De Giovanni, Domenico

    2010-01-01

    The surrender option embedded in many life insurance products is a clause that allows policyholders to terminate the contract early. Pricing techniques based on the American Contingent Claim (ACC) theory are often used, though the actual policyholders' behavior is far from optimal. Inspired by many...... prepayment models for mortgage backed securities, this paper builds a Rational Expectation (RE) model describing the policyholders' behavior in lapsing the contract. A market model with stochastic interest rates is considered, and the pricing is carried out through numerical approximation...... of the corresponding two-space-dimensional parabolic partial differential equation. Extensive numerical experiments show the differences in terms of pricing and interest rate elasticity between the ACC and RE approaches as well as the sensitivity of the contract price with respect to changes in the policyholders...

  11. Lapse Rate Modeling

    DEFF Research Database (Denmark)

    De Giovanni, Domenico

    The surrender option embedded in many life insurance products is a clause that allows policyholders to terminate the contract early. Pricing techniques based on the American Contingent Claim (ACC) theory are often used, though the actual policyholders' behavior is far from optimal. Inspired by many...... prepayment models for mortgage backed securities, this paper builds a Rational Expectation (RE) model describing the policyholders' behavior in lapsing the contract. A market model with stochastic interest rates is considered, and the pricing is carried out through numerical approximation...... of the corresponding two-space-dimensional parabolic partial differential equation. Extensive numerical experiments show the differences in terms of pricing and interest rate elasticity between the ACC and RE approaches as well as the sensitivity of the contract price with respect to changes in the policyholders...

  12. A-3 Construction Time Lapse

    Science.gov (United States)

    2009-01-01

    A time lapse from start to finish of steel erection for the 235-foot tall A-3 Test Stand. Ground work for the stand was broken in August 2008 and the final structural steel beam was placed April 9, 2009.

  13. Twelve tips for addressing medical student and resident physician lapses in professionalism.

    Science.gov (United States)

    Rougas, Steven; Gentilesco, Bethany; Green, Emily; Flores, Libertad

    2015-01-01

    Medical educators have gained significant ground in the practical and scholarly approach to professionalism. When a lapse occurs, thoughtful remediation to address the underlying issue can have a positive impact on medical students and resident physicians, while failure to address lapses, or to do so ineffectively, can have long-term consequences for learners and potentially patients. Despite these high stakes, educators are often hesitant to address lapses in professionalism, possibly due to a lack of time and familiarity with the process. Attention must be paid to generalizable, hands-on recommendations for daily use so that clinicians and administrators feel well equipped to tackle this often difficult yet valuable task. This article reviews the literature related to addressing unprofessional behavior among trainees in medicine and connects it to the shared experience of medical educators at one institution. The framework presented aims to provide practical guidance and empowerment for educators responsible for addressing medical student and resident physician lapses in professionalism.

  14. With Others or Alone? Adolescent Individual Differences in the Context of Smoking Lapses

    Science.gov (United States)

    Roberts, Megan E.; Bidwell, L. Cinnamon; Colby, Suzanne M.; Gwaltney, Chad J.

    2015-01-01

    Objective Although a great deal of adolescent smoking research has investigated predictors of initiation, much less has focused on predictors of lapsing during a quit attempt. In particular, the role of social context may deserve greater attention in models of adolescent smoking cessation. Therefore, the present investigation aimed to use ecological momentary assessment (EMA) in order to examine individual differences in social lapsing—the extent to which lapses occur around others vs. when alone. Methods Analyses focused on 179 adolescent smokers (aged 14-18) engaged in an unassisted quit attempt. There were two general EMA assessment intervals: pre-quit (1 week) and post-quit (2 weeks). Participants reported every time that they smoked a cigarette and at random, nonsmoking times; in each assessment, participants responded to questions about their current environment, behaviors, and psychological state. A 3-month follow-up assessed longer-term smoking-related outcomes. Results Consistent with other adolescent research, the overall rate of lapsing was very high (93%). Social lapsing rates were likewise high (among those who lapsed, 73% reported their first lapse was social), but also varied continuously across individuals. We computed a social lapsing coefficient for each youth, and found that it related to smoking factors at baseline (e.g., lower smoking intensity and dependence) and follow-up (e.g., lower cotinine levels). Conclusions These results suggest that higher rates of social lapsing are associated with being a lighter, less dependent smoker and having better eventual cessation prospects. Findings provide evidence that accounting for variability in social lapsing may improve theory and treatment. PMID:25664557

  15. Nähtamatud lapsed / Margit Tõnson

    Index Scriptorium Estoniae

    Tõnson, Margit, 1978-

    2006-01-01

    UNICEFi palvel valmistasid kaheksa tuntud režissööri kassett-filmi maailma kannatavatest lastest "Kõik nähtamatud lapsed" ("All the Invisible Children") : Prantsusmaa - Itaalia 2005. Film on Sõpruse kino kavas

  16. Haridus - iga lapse õigus / Gerd Tarand

    Index Scriptorium Estoniae

    Tarand, Gerd, 1985-

    2009-01-01

    MTÜ Mondo alustas veebruaris maailmaharidusprojektiga „Haridus - iga lapse õigus“, mille üldine eesmärk on tõsta Eesti elanikkonna, eriti noorte huvi arengumaade vastu ning teadmisi ja arusaamist arengumaade haridusega seonduvatest probleemidest

  17. Jehoova tunnistajate lapse arstide kriminaalasjast / Ants Nõmper

    Index Scriptorium Estoniae

    Nõmper, Ants, 1977-

    2000-01-01

    Kriminaalasjast, kus süüdistati arste meditsiinilise abi osutamata jätmises lapsele, kelle vanemad ei nõustunud vereülekandega. Arsti ravikohustusest, lapse enesemääramisõigusest, vanemlike õiguste piiridest. Arstieetika koodeksitest. Arstiabi mitteandmise kriminaalmenetlusest Saksamaal

  18. Lapse varajastest sotsialiseerumisvõimalustest / Inna Järva

    Index Scriptorium Estoniae

    Järva, Inna

    1998-01-01

    Suhtlemine oma ema või täiskasvanutega on lapse üldise psüühilise arengu tähtsaim faktor. Ema ja lapse suhted sotsiaalsete teooriate valguses, lapse varajased sotsialiseerumise võimalused väikelaste mängukoolide kaudu (Ave Kumpase väikelapse mängukool)

  19. Multimodal and time-lapse skin registration.

    Science.gov (United States)

    Madan, S; Dana, K J; Cula, G O

    2015-08-01

    Computational skin analysis is revolutionizing modern dermatology. Patterns extracted from image sequences enable algorithmic evaluation. Stacking multiple images to analyze pattern variation implicitly assumes that the images are aligned per-pixel. However, breathing and involuntary motion of the patient causes significant misalignment. Alignment algorithms designed for multimodal and time-lapse skin images can solve this problem. Sequences from multi-modal imaging capture unique appearance features in each modality. Time-lapse image sequences capture skin appearance change over time. Multimodal skin images have been acquired under five different modalities: three in reflectance (visible, parallel-polarized, and cross-polarized) and two in fluorescence mode (UVA and blue light excitation). For time-lapse imagery, 39 images of acne lesions over a 3-month period have been collected. The method detects micro-level features like pores, wrinkles, and other skin texture markings in the acquired images. Images are automatically registered to subpixel accuracy. The proposed registration approach precisely aligns multimodal and time-lapse images. Subsurface recovery from multimodal images has misregistration artefacts that can be eliminated using this approach. Registered time-lapse imaging captures the evolution of appearance of skin regions with time. Misalignment in skin imaging has significant impact on any quantitative or qualitative image evaluation. Micro-level features can be used to obtain highly accurate registration. Multimodal images can be organized with maximal overlap for successful registration. The resulting point-to-point alignment improves the quality of skin image analysis. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Predicting the Initial Lapse Using a Mobile Health Application after Alcohol Detoxification

    Science.gov (United States)

    Chih, Ming-Yuan

    2013-01-01

    The prediction and prevention of the initial lapse--which is defined as the first lapse after a period of abstinence--is important because the initial lapse often leads to subsequent lapses (within the same lapse episode) or relapse. The prediction of the initial lapse may allow preemptive intervention to be possible. This dissertation reports on…

  1. How Long Can Students Pay Attention in Class? A Study of Student Attention Decline Using Clickers

    Science.gov (United States)

    Bunce, Diane M.; Flens, Elizabeth A.; Neiles, Kelly Y.

    2010-01-01

    Students enrolled in three levels of general chemistry self-reported their attention decline during both lecture and other teaching approaches via personal response devices (clickers). Students report attention declines of 1 min or less more often than longer attention lapses. The data suggest that student engagement alternates between attention…

  2. Understanding physical activity lapses among women: responses to lapses and the potential buffering effect of social support.

    Science.gov (United States)

    Schumacher, Leah M; Arigo, Danielle; Thomas, Coco

    2017-10-01

    Many women fail to meet recommended levels of physical activity (PA). Limited research has examined women's barriers to PA adoption during attempts to increase PA-in particular, how often they experience PA lapses (i.e., failure to meet PA goals), their cognitive-affective responses to lapses, and the role of social support in preventing or responding to lapses. The present study assessed weekly variability in PA lapses, cognitive-affective responses to lapses, and social support related to PA among women participating in a partner-based PA program (n = 20). Multilevel modeling showed that greater PA self-efficacy and more frequent partner communication predicted fewer lapses during the concurrent or subsequent week (ps self-forgiveness for lapsing also predicted more lapses the subsequent week (p = 0.04), though greater perceived partner support appeared to buffer the negative effect of self-forgiveness on future lapses (p = 0.04). These findings demonstrate the importance of cognitive-affective responses to PA lapses for future PA, as well as the potential benefit of social support for preventing PA lapses among women.

  3. Time-lapse photogrammetry in geomorphic studies

    Science.gov (United States)

    Eltner, Anette; Kaiser, Andreas

    2017-04-01

    Image based approaches to reconstruct the earth surface (Structure from Motion - SfM) are establishing as a standard technology for high resolution topographic data. This is amongst other advantages due to the comparatively ease of use and flexibility of data generation. Furthermore, the increased spatial resolution led to its implementation at a vast range of applications from sub-mm to tens-of-km scale. Almost fully automatic calculation of referenced digital elevation models allows for a significant increase of temporal resolution, as well, potentially up to sub-second scales. Thereby, the setup of a time-lapse multi-camera system is necessary and different aspects need to be considered: The camera array has to be temporary stable or potential movements need to be compensated by temporary stable reference targets/areas. The stability of the internal camera geometry has to be considered due to a usually significantly lower amount of images of the scene, and thus redundancy for parameter estimation, compared to more common SfM applications. Depending on the speed of surface change, synchronisation has to be very accurate. Due to the usual application in the field, changing environmental conditions important for lighting and visual range are also crucial factors to keep in mind. Besides these important considerations much potential is comprised by time-lapse photogrammetry. The integration of multi-sensor systems, e.g. using thermal cameras, enables the potential detection of other processes not visible with RGB-images solely. Furthermore, the implementation of low-cost sensors allows for a significant increase of areal coverage and their setup at locations, where a loss of the system cannot be ruled out. The usage of micro-computers offers smart camera triggering, e.g. acquiring images with increased frequency controlled by a rainfall-triggered sensor. In addition these micro-computers can enable on-site data processing, e.g. recognition of increased surface

  4. Lapse in Institutional Animal Care and Use Committee Continuing Reviews.

    Directory of Open Access Journals (Sweden)

    Min-Fu Tsan

    Full Text Available The United States federal animal welfare regulations and the Public Health Service Policy on Humane Care and Use of Laboratory Animals require that institutional animal care and use committees (IACUCs conduct continuing reviews of all animal research activities. However, little is known about the lapse rate of IACUC continuing reviews, and how frequently investigators continue research activities during the lapse. It is also not clear what factors may contribute to an institution's lapse in IACUC continuing reviews. As part of the quality assurance program, the Department of Veterans Affairs (VA has collected performance metric data for animal care and use programs since 2011. We analyzed IACUC continuing review performance data at 74-75 VA research facilities from 2011 through 2015. The IACUC continuing review lapse rates improved from 5.6% in 2011 to 2.7% in 2015. The rate of investigators continuing research activities during the lapse also decreased from 47.2% in 2012 to 7.4% in 2015. The type of IACUCs used and the size of animal research programs appeared to have no effect in facility's rates of lapse in IACUC continuing reviews. While approximately 80% of facilities reported no lapse in IACUC continuing reviews, approximately 14% of facilities had lapse rates of >10% each year. Some facilities appeared to be repeat offenders. Four facilities had IACUC lapse rates of >10% in at least 3 out of 5 years, suggesting a system problem in these facilities requiring remedial actions to improve their IACUC continuing review processes.

  5. Can arousing feedback rectify lapses in driving? Prediction from EEG power spectra

    Science.gov (United States)

    Lin, Chin-Teng; Huang, Kuan-Chih; Chuang, Chun-Hsiang; Ko, Li-Wei; Jung, Tzyy-Ping

    2013-10-01

    Objective. This study explores the neurophysiological changes, measured using an electroencephalogram (EEG), in response to an arousing warning signal delivered to drowsy drivers, and predicts the efficacy of the feedback based on changes in the EEG. Approach. Eleven healthy subjects participated in sustained-attention driving experiments. The driving task required participants to maintain their cruising position and compensate for randomly induced lane deviations using the steering wheel, while their EEG and driving performance were continuously monitored. The arousing warning signal was delivered to participants who experienced momentary behavioral lapses, failing to respond rapidly to lane-departure events (specifically the reaction time exceeded three times the alert reaction time). Main results. The results of our previous studies revealed that arousing feedback immediately reversed deteriorating driving performance, which was accompanied by concurrent EEG theta- and alpha-power suppression in the bilateral occipital areas. This study further proposes a feedback efficacy assessment system to accurately estimate the efficacy of arousing warning signals delivered to drowsy participants by monitoring the changes in their EEG power spectra immediately thereafter. The classification accuracy was up 77.8% for determining the need for triggering additional warning signals. Significance. The findings of this study, in conjunction with previous studies on EEG correlates of behavioral lapses, might lead to a practical closed-loop system to predict, monitor and rectify behavioral lapses of human operators in attention-critical settings.

  6. Slips, lapses and mistakes inthe use of equipment by nurses in an intensive care unit

    Directory of Open Access Journals (Sweden)

    Gabriella da Silva Rangel Ribeiro

    2016-06-01

    Full Text Available Abstract OBJECTIVE Toidentify the occurrence of errors in the use of equipment by nurses working in intensive careandanalyzing them in the framework of James Reason's theory of human error. METHOD Qualitative field study in the intensive care unit of a federal hospital in the city of Rio de Janeiro. Observation and interviews were conductedwith eight nurses, from March to December 2014. Content analysis was used for the interviews, as well as the description of the scenes observed. RESULTS Lapses of memory and attention were identified in the handling of infusion pumps, as well as planning failures during the programming of monitors. CONCLUSION Errors cause adverse events that compromise patient safety. The authors propose creation of an instrument for daily checking of equipment, with checks throughout the work process in the programming of infusion pumps and monitors, in order to reduce failures and memory lapses.

  7. The tropical lapse rate steepened during the Last Glacial Maximum

    NARCIS (Netherlands)

    Loomis, S.E.; Russell, J.M.; Verschuren, D.; Morrill, C.; De Cort, G.; Sinninghe Damsté, J.S.; Olago, D.; Eggermont, H.; Street-Perrott, F.A.; Kelly, M.A.

    2017-01-01

    The gradient of air temperature with elevation (the temperature lapse rate) in the tropics is predicted to become lesssteep during the coming century as surface temperature rises, enhancing the threat of warming in high-mountainenvironments. However, the sensitivity of the lapse rate to climate

  8. The tropical lapse rate steepened during the Last Glacial Maximum

    NARCIS (Netherlands)

    Loomis, Shannon E; Russell, James M; Verschuren, Dirk; Morrill, Carrie; De Cort, Gijs; Sinninghe Damsté, Jaap S; Olago, Daniel; Eggermont, Hilde; Street-Perrott, F Alayne; Kelly, Meredith A

    The gradient of air temperature with elevation (the temperature lapse rate) in the tropics is predicted to become less steep during the coming century as surface temperature rises, enhancing the threat of warming in high-mountain environments. However, the sensitivity of the lapse rate to climate

  9. Lapse ülalpidamise hind / Ene-Margit Tiit

    Index Scriptorium Estoniae

    Tiit, Ene-Margit, 1934-

    2005-01-01

    Tutvustav artikkel sotsiaalministeeriumi tellimusel läbiviidud uuringust, mille eesmärgiks oli välja töötada lapse kõikidest vajadustest lähtuv ühtne metoodika lapse ülalpidamiskulude arvutamiseks ühes kuus. Tabelid. Diagrammid. Vt. ka lk. 15-16: Kaplan, Signe. Metoodika kasutamisvõimalusi

  10. Closed-loop training of attention with real-time brain imaging.

    Science.gov (United States)

    deBettencourt, Megan T; Cohen, Jonathan D; Lee, Ray F; Norman, Kenneth A; Turk-Browne, Nicholas B

    2015-03-01

    Lapses of attention can have negative consequences, including accidents and lost productivity. Here we used closed-loop neurofeedback to improve sustained attention abilities and reduce the frequency of lapses. During a sustained attention task, the focus of attention was monitored in real time with multivariate pattern analysis of whole-brain neuroimaging data. When indicators of an attentional lapse were detected in the brain, we gave human participants feedback by making the task more difficult. Behavioral performance improved after one training session, relative to control participants who received feedback from other participants' brains. This improvement was largest when feedback carried information from a frontoparietal attention network. A neural consequence of training was that the basal ganglia and ventral temporal cortex came to represent attentional states more distinctively. These findings suggest that attentional failures do not reflect an upper limit on cognitive potential and that attention can be trained with appropriate feedback about neural signals.

  11. 77 FR 38396 - Agency Information Collection (Notice of Lapse-Government Life Insurance) Activities Under OMB...

    Science.gov (United States)

    2012-06-27

    ... AFFAIRS Agency Information Collection (Notice of Lapse--Government Life Insurance) Activities Under OMB... INFORMATION: Titles: a. Notice of Lapse--Government Life Insurance, VA Form 29-389. b. Application for... government life insurance has lapsed or will lapse due to nonpayment of premiums. The claimant must complete...

  12. Attention to Attention

    DEFF Research Database (Denmark)

    Tække, Jesper; Paulsen, Michael Eric

    In these years digital media and wireless networks are introduced in upper secondary schools in Denmark. This implies new “attentional objects” like updates on Facebook or tweets on Twitter within instant reach of the pupils and teachers. Also it implies new kinds of attention (awareness) like when...... this interpretation theoretically through systems theory and medium theory. Further we present initial results from the action research project Socio Media Education (SME) in which we work with how teachers and pupils can handle the new attention-demanding situation, so the new media do not mean spoiled teaching...

  13. Kohtu loal lapse nimel tehingute tegemine krediidiasutuses : [magistritöö] / Merily Saar ; Tartu Ülikool, õigusteaduskond ; juhendaja: Triin Göttig

    Index Scriptorium Estoniae

    Saar, Merily, 1987-

    2013-01-01

    Varahooldusõigusest tulenevast lapse vara säilitamise kohustusest, perekonnaseadusest tulenevatest piirangutest vanema poolt lapse esindajana tehingute tegemisel, lapse nimel väärtpaberitehingute tegemisest

  14. Temperature lapse rate as an adjunct to wind shear detection

    Science.gov (United States)

    Zweifil, Terry

    1991-01-01

    Several meteorological parameters were examined to determine if measurable atmospheric conditions can improve windshear detection devices. Lapse rate, the temperature change with altitude, shows promise as being an important parameter in the prediction of severe wind shears. It is easily measured from existing aircraft instrumentation, and it can be important indicator of convective activity including thunderstorms and microbursts. The meteorological theory behind lapse rate measurement is briefly reviewed, and and FAA certified system is described that is currently implemented in the Honeywell Wind Shear Detection and Guidance System.

  15. Ecological momentary assessment of self-attitudes in response to dietary lapses.

    Science.gov (United States)

    Schumacher, Leah M; Martin, Gerald J; Goldstein, Stephanie P; Manasse, Stephanie M; Crosby, Ross D; Butryn, Meghan L; Lillis, Jason; Forman, Evan M

    2018-02-01

    To examine whether self-attitudes and self-efficacy after dietary lapses relate to lapse frequency or predict risk for lapsing again on the same day. Adults with overweight/obesity (n = 91) completed ecological momentary assessment for 14 days at the start of a lifestyle modification program. At each survey, participants reported whether they had experienced a dietary lapse, and, if so, reported their self-attitudes (i.e., self-criticism, self-forgiveness, self-regard) and self-efficacy. The relationships between participants' typical (i.e., average level for each participant across lapses) self-attitudes/self-efficacy after lapsing and lapse frequency were examined using correlations. Generalized estimating equations examined whether participants' typical (average across lapses; between-person effect) self-attitudes/self-efficacy or momentary (i.e., level of each variable at a particular lapse relative to one's typical level; within-person effect) self-attitudes/self-efficacy predicted same-day lapse occurrence. Lower typical self-efficacy and more negative typical self-regard related to greater lapse frequency. Additionally, lower momentary self-criticism predicted greater likelihood of same-day lapse occurrence. There also was a quadratic relationship between typical self-regard and risk of same-day lapse occurrence, such that individuals with either more negative or more positive typical self-regard were more likely to lapse on the same day. Findings provide preliminary support for the relevance of self-attitudes and self-efficacy to lapses during early lifestyle modification. While greater typical self-efficacy and more positive typical self-regard are associated with fewer lapses, lower momentary self-criticism and very positive or negative typical self-regard may confer risk for same-day lapses. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  16. 26 CFR 25.2704-1 - Lapse of certain rights.

    Science.gov (United States)

    2010-04-01

    ... GIFT TAXES GIFT TAX; GIFTS MADE AFTER DECEMBER 31, 1954 Special Valuation Rules § 25.2704-1 Lapse of... governing instruments are less restrictive than the State law that would apply in the absence of the... Corporation Y and D's children owned all the common stock. At that time, the preferred stock had 60 percent of...

  17. Time-lapse controlled-source electromagnetics using interferometry

    NARCIS (Netherlands)

    Hunziker, J.W.; Slob, E.C.; Wapenaar, C.P.A.

    In time-lapse controlled-source electromagnetics, it is crucial that the source and the receivers are positioned at exactly the same location at all times of measurement. We use interferometry by multidimensional deconvolution (MDD) to overcome problems in repeatability of the source location.

  18. Andeka lapse arengukeskkond ja toimetulek koolis / Helle Sikka

    Index Scriptorium Estoniae

    Sikka, Helle

    2001-01-01

    Andekuse mõistest ja selle arengust, andeka lapse isiksuseomadustest. 1998-2000.a. läbi viidud küsitlusuuringust, mille eesmärgiks oli selgitada andekate laste koolimeeldivust, hinnanguid õpetajatele, õpilaste asendit kaaslaste seas, õpilaste arvamusi oma isiksuseomaduste kohta ning andekate harrastusi ja huvisid

  19. Arengukeskkonna mõju lapse intelligentsuse arengule / Marika Veisson, Kristina Nugin

    Index Scriptorium Estoniae

    Veisson, Marika

    2002-01-01

    Uuringust, mille eesmärgiks oli määratleda 3-4-aastaste laste kasvukeskkonna faktorite mõju lapse intelligentsuse arengule, eraldi on vaadeldud intelligentsuse erinevaid komponente. Uuritavateks olid 1996-2002.a. longituuduuringus osalenud lapsed. Alates 1999.a. võrreldi nende laste arengu näitajaid kontrollgrupiga, mille moodustasid tavalasteaia ja Hea Alguse programmis osalenud lapsed

  20. TimeLapseAnalyzer: Multi-target analysis for live-cell imaging and time-lapse microscopy

    DEFF Research Database (Denmark)

    Huth, Johannes; Buchholz, Malte; Kraus, Johann M.

    2011-01-01

    The direct observation of cells over time using time-lapse microscopy can provide deep insights into many important biological processes. Reliable analyses of motility, proliferation, invasive potential or mortality of cells are essential to many studies involving live cell imaging and can aid...

  1. Are lapsed donors willing to resume blood donation, and what determines their motivation to do so?

    Science.gov (United States)

    van Dongen, Anne; Abraham, Charles; Ruiter, Robert A C; Schaalma, Herman P; de Kort, Wim L A M; Dijkstra, J Anneke; Veldhuizen, Ingrid J T

    2012-06-01

    This study investigated the possibility of rerecruiting lapsed blood donors. Reasons for donation cessation, motivation to restart donation, and modifiable components of donation motivation were examined. We distinguished between lapsed donors who had passively withdrawn by merely not responding to donation invitations and donors who had contacted the blood bank to actively withdraw. A cross-sectional survey was sent to 400 actively lapsed donors and to 400 passively lapsed donors, measuring intention to restart donation and psychological correlates of restart intention. The data were analyzed using multiple regression analyses. The response rate among actively lapsed donors was higher than among passively lapsed donors (37% vs. 25%). Actively lapsed donors typically ceased donating because of physical reactions, while passively lapsed donors quit because of a busy lifestyle. Nonetheless, 51% of actively lapsed responders and 80% of passively lapsed responders were willing to restart donations. Multiple regression analysis showed that, for passively lapsed donors, cognitive attitude was the strongest correlate of intention to donate in the future (β=0.605, pattitude (β=0.239, pattitude was also the strongest correlate of intention (β=0.601, pattitude (β=0.345, pattitudes and self-efficacy could further raise such intentions. © 2011 American Association of Blood Banks.

  2. Calibrating vadose zone models with time-lapse gravity data

    DEFF Research Database (Denmark)

    Christiansen, Lars; Binning, Philip John; Rosbjerg, Dan

    2011-01-01

    The vadose zone plays an important role in the hydrologic cycle. Various geophysical methods can determine soil water content variations in time and space in volumes ranging from a few cubic centimeters to several cubic meters. In contrast to the established methods, time-lapse gravity measurements...... of changes in soil water content do not rely on a petrophysical relationship between the measured quantity and the water content but give a direct measure of the mass change in the soil. Only recently has the vadose zone been systematically incorporated when ground-based gravity data are used to infer...... hydrologic information. In this study, changes in the soil water content gave rise to a measurable signal in a forced infiltration experiment on a 107-m2 grassland area. Time-lapse gravity data were able to constrain the van Genuchten soil hydraulic parameters in both a synthetic example and a field...

  3. Time-lapse stereo-photogrammetric monitoring of volcanic slopes

    OpenAIRE

    Dewez, Thomas; Moser, Simon

    2013-01-01

    Piton de la Fournaise volcano (La Reunion Island) due to its crater collapse of April 2007 which created 200m to 300-m-high sub-vertical cliffs in a matter of minutes offers a rare opportunity to observe the morphological fingerprint of numerous rock avalanches. In the framework of ANR-Undervolc, a research project funded by the French Research Council to investigate geophysical determinants of volcano construction and destruction, a pair of time lapse photogrammetric packages was deployed al...

  4. Water vapor pressure versus environmental lapse rate near the tropopause

    Science.gov (United States)

    Ferreira, Antonio; Castanheira, Jose; Gimeno, Luis

    2010-05-01

    The relationship between water vapor pressure and temperature lapse rate in the vicinity of the tropopause was investigated using in situ observations. The water vapor partial pressures and the lapse rates within a vertical distance of ±1.5 km around the first thermal tropopause were calculated from the vertical soundings conducted by the NOAA/CMDL at several locations in the last few decades (GMD Data Archive). A positive non-linear relationship between the two quantities was found to hold across the studied tropopause region at mid-latitudes and polar latitudes. A similar analysis was performed on the 300 and 250 hPa pressure levels (which often intercept the tropopause region), by collecting temperature and humidity observations within 1979-2008 from the Integrated Global Radiosonde Archive (IGRA). A relationship having almost the same shape was detected for statically stable lapse rates at all latitude zones. Given the relevance of water vapor in the radiative transfer in the upper troposphere, the results are an indication of a local influence of water vapor on the thermal structure of the transition layer between the troposphere and stratosphere

  5. Slips, lapses and mistakes inthe use of equipment by nurses in an intensive care unit.

    Science.gov (United States)

    Ribeiro, Gabriella da Silva Rangel; Silva, Rafael Celestino da; Ferreira, Márcia de Assunção; Silva, Grazielle Rezende da

    2016-01-01

    Toidentify the occurrence of errors in the use of equipment by nurses working in intensive careandanalyzing them in the framework of James Reason's theory of human error. Qualitative field study in the intensive care unit of a federal hospital in the city of Rio de Janeiro. Observation and interviews were conductedwith eight nurses, from March to December 2014. Content analysis was used for the interviews, as well as the description of the scenes observed. Lapses of memory and attention were identified in the handling of infusion pumps, as well as planning failures during the programming of monitors. Errors cause adverse events that compromise patient safety. The authors propose creation of an instrument for daily checking of equipment, with checks throughout the work process in the programming of infusion pumps and monitors, in order to reduce failures and memory lapses. Identificar a ocorrência de erros na utilização de equipamentos por enfermeiros que atuam na terapia intensiva, analisando-os à luz da teoria do erro humano de James Reason. Pesquisa de campo, qualitativa, na Unidade de Terapia Intensiva de um hospital federal do Rio de Janeiro. Realizou-se observação e entrevista com oito enfermeiros, de março a dezembro de 2014. Aplicou-se análise de conteúdo nas entrevistas e descrição densa nas cenas observadas. Identificaram-se falhas de memória e de atenção no manuseio das bombas infusoras e falhas de planejamento durante a programação dos monitores. Os erros causam eventos adversos que comprometem a segurança do paciente. Propõe-se um instrumento de verificação diária dos equipamentos, com checagens ao longo do processo de trabalho da programação das bombas infusoras e monitores, no intuito de reduzir as falhas e esquecimentos.

  6. Distinct coping strategies differentially predict urge levels and lapses in a smoking cessation attempt.

    Science.gov (United States)

    Brodbeck, Jeannette; Bachmann, Monica S; Znoj, Hansjörg

    2013-06-01

    This study analysed mechanisms through which stress-coping and temptation-coping strategies were associated with lapses. Furthermore, we explored whether distinct coping strategies differentially predicted reduced lapse risk, lower urge levels, or a weaker association between urge levels and lapses during the first week of an unassisted smoking cessation attempt. Participants were recruited via the internet and mass media in Switzerland. Ecological momentary assessment (EMA) with mobile devices was used to assess urge levels and lapses. Online questionnaires were used to measure smoking behaviours and coping variables at baseline, as well as smoking behaviour at the three-month follow-up. The sample consisted of 243 individuals, aged 20 to 40, who reported 4199 observations. Findings of multilevel regression analyses show that coping was mainly associated with a reduced lapse risk and not with lower urge levels or a weaker association between urge levels and lapses. 'Calming down' and 'commitment to change' predicted a lower lapse risk and also a weaker relation between urge levels and lapses. 'Stimulus control' predicted a lower lapse risk and lower urge levels. Conversely, 'task-orientation' and 'risk assessment' were related to higher lapse risk and 'risk assessment' also to higher urge levels. Disengagement coping i.e. 'eating or shopping', 'distraction', and 'mobilising social support' did not affect lapse risk. Promising coping strategies during the initial stage of smoking cessation attempt are targeted directly at reducing the lapse risk and are characterised by engagement with the stressor or one's reactions towards the stressor and a focus on positive consequences instead of health risks. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Calibrating Vadose Zone Models with Time-Lapse Gravity Data

    DEFF Research Database (Denmark)

    Christiansen, Lars; Hansen, A. B.; Looms, M. C.

    2009-01-01

    A change in soil water content is a change in mass stored in the subsurface. Given that the mass change is big enough, the change can be measured with a gravity meter. Attempts have been made with varying success over the last decades to use ground-based time-lapse gravity measurements to infer...... experiment on 10m by 10m grass land. Simulation studies show a potential for vadose zone model calibration using gravity data in conjunction with other geophysical data, e.g. cross-borehole georadar. We present early field data and calibration results from a forced infiltration experiment conducted over 30...

  8. Interferometric full-waveform inversion of time-lapse data

    KAUST Repository

    Sinha, Mrinal

    2017-08-17

    One of the key challenges associated with time-lapse surveys is ensuring the repeatability between the baseline and monitor surveys. Non-repeatability between the surveys is caused by varying environmental conditions over the course of different surveys. To overcome this challenge, we propose the use of interferometric full waveform inversion (IFWI) for inverting the velocity model from data recorded by baseline and monitor surveys. A known reflector is used as the reference reflector for IFWI, and the data are naturally redatumed to this reference reflector using natural reflections as the redatuming operator. This natural redatuming mitigates the artifacts introduced by the repeatability errors that originate above the reference reflector.

  9. 77 FR 22069 - Proposed Information Collection (Notice of Lapse-Government Life Insurance); Comment Request

    Science.gov (United States)

    2012-04-12

    ... AFFAIRS Proposed Information Collection (Notice of Lapse--Government Life Insurance); Comment Request... Life Insurance policy. DATES: Written comments and recommendations on the proposed collection of... use of other forms of information technology. Titles a. Notice of Lapse--Government Life Insurance, VA...

  10. Exploring Time-Lapse Photography as a Means for Qualitative Data Collection

    Science.gov (United States)

    Persohn, Lindsay

    2015-01-01

    Collecting information via time-lapse photography is nothing new. Scientists and artists have been using this kind of data since the late 1800s. However, my research and experiments with time-lapse have shown that great potential may lie in its application to educational and social scientific research methods. This article is part history, part…

  11. Effectiveness of continuing nicotine replacement after a lapse: A randomized trial.

    Science.gov (United States)

    Hughes, John R; Solomon, Laura J; Peasley-Miklus, Catherine E; Callas, Peter W; Fingar, James R

    2018-01-01

    Four post-hoc analyses of prior trials found smokers using nicotine patch following a lapse were less likely to progress to relapse compared to those using a placebo patch following a lapse. We attempted a conceptual replication test of these results via a randomized trial of instructions to continue vs. stop nicotine patch after a lapse. Smokers trying to quit (n=701) received nicotine patch (21/14/7mg) and brief phone counseling (six 15-min sessions). We randomized smokers to receive instructions for and rationale for stopping vs. continuing patch after a lapse. The messages were repeated before and after cessation and following lapses via counseling, phone and written instructions. Among those who lapsed, those told to Continue Patch did not have a greater incidence of 7-day abstinence at 4months (primary outcome) than those told to Discontinue Patch (51% vs. 46%). Most (81%) participants in the Discontinue condition stopped patch for only 1-2days and then resumed abstinence and patch use. Analyses based on all participants randomized were similar. Adverse events were as expected and did not differ between conditions. Instructions to continue nicotine patch after a lapse did not increase return to abstinence. These negative results may have occurred because actual use of patch after a lapse was similar in the two conditions. Also, allowing patch use while smoking may have reduced motivation to stay abstinent. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. First Lapses to Smoking: Within-Subjects Analysis of Real-Time Reports.

    Science.gov (United States)

    Shiffman, Saul; And Others

    1996-01-01

    Studies of smoking relapse and temptation have relied on retrospective recall and confounded between- and within-subject variability. Real-time data on temptations and lapses to smoke were gathered using palm-top computers in 108 ex-smokers. Made within-subject comparisons of initial lapse, a temptation episode, and base rate data obtained through…

  13. Capturing change: the duality of time-lapse imagery to acquire data and depict ecological dynamics

    Science.gov (United States)

    Brinley Buckley, Emma M.; Allen, Craig R.; Forsberg, Michael; Farrell, Michael; Caven, Andrew J.

    2017-01-01

    We investigate the scientific and communicative value of time-lapse imagery by exploring applications for data collection and visualization. Time-lapse imagery has a myriad of possible applications to study and depict ecosystems and can operate at unique temporal and spatial scales to bridge the gap between large-scale satellite imagery projects and observational field research. Time-lapse data sequences, linking time-lapse imagery with data visualization, have the ability to make data come alive for a wider audience by connecting abstract numbers to images that root data in time and place. Utilizing imagery from the Platte Basin Timelapse Project, water inundation and vegetation phenology metrics are quantified via image analysis and then paired with passive monitoring data, including streamflow and water chemistry. Dynamic and interactive time-lapse data sequences elucidate the visible and invisible ecological dynamics of a significantly altered yet internationally important river system in central Nebraska.

  14. Seismic imaging of reservoir flow properties: Time-lapse amplitude changes

    Energy Technology Data Exchange (ETDEWEB)

    Vasco, D.W.; Datta-Gupta, Akhil; Behrens, Ron; Condon, Pat; Rickett, Jame s

    2003-03-13

    Asymptotic methods provide an efficient means by which to infer reservoir flow properties, such as permeability, from time-lapse seismic data. A trajectory-based methodology, much like ray-based methods for medical and seismic imaging, is the basis for an iterative inversion of time-lapse amplitude changes. In this approach a single reservoir simulation is required for each iteration of the algorithm. A comparison between purely numerical and the trajectory-based sensitivities demonstrates their accuracy. An application to a set of synthetic amplitude changes indicates that they can recover large-scale reservoir permeability variations from time-lapse data. In an application of actual time-lapse amplitude changes from the Bay Marchand field in the Gulf of Mexico we are able to reduce the misfit by 81% in twelve iterations. The time-lapse observations indicate lower permeabilities are required in the central portion of the reservoir.

  15. A Prototype System for Time-Lapse Electrical Resistivity Tomographies

    Directory of Open Access Journals (Sweden)

    Raffaele Luongo

    2012-01-01

    Full Text Available A prototype system for time-lapse acquisition of 2D electrical resistivity tomography (ERT and time domain reflectometry (TDR measurements was installed in a test site affected by a landslide in Basilicata region (southern Italy. The aim of the system is to monitor in real-time the rainwater infiltration into the soil and obtain information about the variation of the water content in the first layers of the subsoil and the possible influence of this variation on landslide activity. A rain gauge placed in the test site gives information on the rainfall intensity and frequency and suggests the acquisition time interval. The installed system and the preliminary results are presented in this paper.

  16. Measuring slips and lapses when they occur - ambulatory assessment in application to cognitive failures.

    Science.gov (United States)

    Lange, Stefanie; Süß, Heinz-Martin

    2014-02-01

    Cognitive failures are lapses in attention, cognition, and actions that everybody experiences in everyday life. Self-reports are mainly used for assessment but those instruments are memory-biased and more related to personality aspects than to actual behavior. Ambulatory assessment is already used for capturing emotions or addictive behavior, but not yet for cognitive failures. The newly developed Questionnaire for Cognitive Failures in Everyday Life (KFA) was applied via mobile phones (electronic KFA) wherein an acoustic signal asked participants (N=91, 60-76 years) 4 times daily to answer 13 questions for 1 week. The new instrument showed satisfying reliability and was compared with a self-report method (Cognitive Failures Questionnaire; Broadbent, Cooper, Fitzgerald, and Parkes, 1982) in terms of correlations with cognitive abilities (working memory capacity, short-term memory, switching ability, and reasoning), personality traits, and demographical aspects. Although further validation is needed, first results are promising and eKFA enriches cognitive failures research. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Attention visuelle

    OpenAIRE

    Rousserie, Marie

    2015-01-01

    William James, philosophe et psychologue américain, est le premier à parler de l’attention en 1890 dans son livre The Principles of Psychology : il dit que c’est un concept connu mais dont personne ne saurait en donner une définition précise. Il la définit alors ainsi : « L'attention est la prise de possession par l'esprit, sous une forme claire et vive, d'un objet ou d'une suite de pensées parmi plusieurs qui semblent possibles […] Elle implique le retrait de certains objets afin de traiter ...

  18. Attention Sensor

    NARCIS (Netherlands)

    Börner, Dirk; Kalz, Marco; Specht, Marcus

    2014-01-01

    This software sketch was used in the context of an experiment for the PhD project “Ambient Learning Displays”. The sketch comprises a custom-built attention sensor. The sensor measured (during the experiment) whether a participant looked at and thus attended a public display. The sensor was built

  19. Exploring the relationship between boredom and sustained attention.

    Science.gov (United States)

    Malkovsky, Ela; Merrifield, Colleen; Goldberg, Yael; Danckert, James

    2012-08-01

    Boredom is a common experience, prevalent in neurological and psychiatric populations, yet its cognitive characteristics remain poorly understood. We explored the relationship between boredom proneness, sustained attention and adult symptoms of attention deficit hyperactivity disorder (ADHD). The results showed that high boredom-prone individuals (HBP) performed poorly on measures of sustained attention and showed increased symptoms of ADHD and depression. The results also showed that HBP individuals can be characterised as either apathetic-in which the individual is unconcerned with his/her environment, or as agitated-in which the individual is motivated to engage in meaningful activities, although attempts to do so fail to satisfy. Apathetic boredom proneness was associated with attention lapses, whereas agitated boredom proneness was associated with decreased sensitivity to errors of sustained attention, and increased symptoms of adult ADHD. Our results suggest there is a complex relationship between attention and boredom proneness.

  20. Network analysis of time-lapse microscopy recordings.

    Science.gov (United States)

    Smedler, Erik; Malmersjö, Seth; Uhlén, Per

    2014-01-01

    Multicellular organisms rely on intercellular communication to regulate important cellular processes critical to life. To further our understanding of those processes there is a need to scrutinize dynamical signaling events and their functions in both cells and organisms. Here, we report a method and provide MATLAB code that analyzes time-lapse microscopy recordings to identify and characterize network structures within large cell populations, such as interconnected neurons. The approach is demonstrated using intracellular calcium (Ca(2+)) recordings in neural progenitors and cardiac myocytes, but could be applied to a wide variety of biosensors employed in diverse cell types and organisms. In this method, network structures are analyzed by applying cross-correlation signal processing and graph theory to single-cell recordings. The goal of the analysis is to determine if the single cell activity constitutes a network of interconnected cells and to decipher the properties of this network. The method can be applied in many fields of biology in which biosensors are used to monitor signaling events in living cells. Analyzing intercellular communication in cell ensembles can reveal essential network structures that provide important biological insights.

  1. Network Analysis of Time-Lapse Microscopy Recordings

    Directory of Open Access Journals (Sweden)

    Erik eSmedler

    2014-09-01

    Full Text Available Multicellular organisms rely on intercellular communication to regulate important cellular processes critical to life. To further our understanding of those processes there is a need to scrutinize dynamical signaling events and their functions in both cells and organisms. Here, we report a method and provide MATLAB code that analyzes time-lapse microscopy recordings to identify and characterize network structures within large cell populations, such as interconnected neurons. The approach is demonstrated using intracellular calcium (Ca2+ recordings in neural progenitors and cardiac myocytes, but could be applied to a wide variety of biosensors employed in diverse cell types and organisms. In this method, network structures are analyzed by applying cross-correlation signal processing and graph theory to single-cell recordings. The goal of the analysis is to determine if the single cell activity constitutes a network of interconnected cells and to decipher the properties of this network. The method can be applied in many fields of biology in which biosensors are used to monitor signaling events in living cells. Analyzing intercellular communication in cell ensembles can reveal essential network structures that provide important biological insights.

  2. Time-lapse Geophysical Data from a Stressed Environment

    Science.gov (United States)

    Milkereit, B.; Tibbo, M.; Kassam, A.; Carey, A.; Schmitt, D. R.; Mohammed, T. E.; Malehmir, R.; Guo, K.

    2015-12-01

    A complication in geophysical monitoring of deep mines is the high-stress dependency of the physical properties of hard rocks. This project is part of a comprehensive, exploration geophysical study in a deep, highly stressed mine located in Sudbury, Ontario, Canada. Data from in situ monitoring of the mining induced seismicity, conductivity, and stress dependent physical properties have been obtained from two boreholes located in this mine. These borehole are approximately 400 m long with NQ diameters and depths of about 1300 - 1600 m and 1700 - 2000 m. Two borehole logging surveys were performed on both boreholes, October 2013 and July 2015, in order to perform a time-lapse analysis of the geophysical changes in the mine. These multi-parameter surveys include caliper, full waveform sonic, televiewer, chargeability (IP), and resistivity. Multi-electrode array DC/IP borehole and borehole-to-borehole surveys were also conducted in 2014, showing an increase in resistivity only in the 1300 m borehole near the active mining area, possibly due to stress induced closing of fractures. There is only exploration activity near the 1700 m borehole over this time period, and it therefore shows no changes in resistivity. Laboratory experiments have been performed on borehole core samples from each borehole. These experiments have measured the geophysical properties including elastic modulus, bulk modulus, P- and S-wave velocities, and density.

  3. Terahertz time-lapse imaging of hydration in physiological tissues

    Science.gov (United States)

    Bennett, David B.; Taylor, Zachary D.; Bajwa, Neha; Tewari, Priyamvada; Maccabi, Ashkan; Sung, Shijun; Singh, Rahul S.; Culjat, Martin O.; Grundfest, Warren S.; Brown, Elliott R.

    2011-02-01

    This study describes terahertz (THz) imaging of hydration changes in physiological tissues with high water concentration sensitivity. A fast-scanning, pulsed THz imaging system (centered at 525 GHz; 125 GHz bandwidth) was utilized to acquire a 35 mm x 35 mm field-of-view with 0.5 mm x 0.5 mm pixels in less than two minutes. THz time-lapsed images were taken on three sample systems: (1) a simple binary system of water evaporating from a polypropylene towel, (2) the accumulation of fluid at the site of a sulfuric acid burn on ex vivo porcine skin, and (3) the evaporative dehydration of an ex vivo porcine cornea. The diffusion-regulating behavior of corneal tissue is elucidated, and the correlation of THz reflectivity with tissue hydration is measured using THz spectroscopy on four ex vivo corneas. We conclude that THz imaging can discern small differences in the distribution of water in physiological tissues and is a good candidate for burn and corneal imaging.

  4. Lapse käsi Riigikogu käes / Aivar Jarne

    Index Scriptorium Estoniae

    Jarne, Aivar, 1965-

    2003-01-01

    Rahvastikuprobleemidega toimetulekuks peab kogu lääne kultuuripiirkond ja iga maa omaette mõtlema, kuidas stimuleerida sündimust, suurendada lapse väärtust perekonnas ja vanemate jaoks, tõdeb autor

  5. Peeter Kreitzberg : võtame vaestelt lapsed ära! / Peeter Kreitzberg ; vahendas Helen Urbanik

    Index Scriptorium Estoniae

    Kreitzberg, Peeter, 1948-2011

    2001-01-01

    Intervjuu Keskerakonna presidendikandidaadi Peeter Kreitzbergiga : Peeter Kreitzbergi ettekanne konverentsil "Teine võimalus hariduses" sisaldas ettepanekut koguda probleemsete ja ebasoodsas keskkonnas elavate perekondade hooletusse jäetud lapsed riigi pansionidesse

  6. History matching of time-lapse crosswell data using ensemble kalman filtering

    KAUST Repository

    de Matos Ravanelli, Fabio Miguel

    2015-09-03

    Data from crosswell seismic surveys is processed to provide crosswell time-lapse data to map fluid changes in a reservoir where time-lapse or 4D seismic data is unavailable or unreliable, such as in onshore reservoirs. The resultant processing results provide quantitative information for history matching purposes using a probabilistic approach to take in account uncertainties in the geological model and reduce uncertainties in reservoir production forecasts.

  7. Speaking up: using OSTEs to understand how medical students address professionalism lapses.

    Science.gov (United States)

    Tucker, Constance R; Choby, Beth A; Moore, Andrew; Parker, Robert Scott; Zambetti, Benjamin R; Naids, Sarah; Scott, Jillian; Loome, Jennifer; Gaffney, Sierra

    2016-01-01

    Objective-structured teaching encounters (OSTEs) are used across many disciplines to assess teaching ability. The OSTE detailed in this paper assesses 191 fourth-year medical students' (M4) ability to identify and address lapses in professionalism based on Association of American Medical Colleges' professionalism competencies. The research questions addressed are How frequently do M4s address professionalism lapses observed during an OSTE? What factors influence whether M4s provide feedback when they observe professionalism lapses in an OSTE? Standardized patients (SPs) and standardized learners (SLs) were recruited and trained to participate in a standardized encounter with specific cognitive, social, and behavioral errors, including professionalism lapses. M4s viewed this encounter and then offered feedback to the SL, while remotely observed by faculty. Post-encounter, the SL and faculty completed identical checklists to assess both teaching readiness and ability to address professionalism concerns. An analysis of frequencies showed that six of the Association of American Medical Colleges' nine professional competencies were addressed in the checklist and/or discussed in the focus group. Analysis of transcribed debriefing sessions confirmed that M4s did not consistently address professionalism lapses by their peers. In focus groups, M4s indicated that, while they noticed professionalism issues, they were uncomfortable discussing them with the SLs. Findings of the current study suggest how medical educators might support learners' ability to address lapses in professionalism as well as topics for future research.

  8. Lapses and psychosocial factors related to physical activity in early postmenopause.

    Science.gov (United States)

    Conroy, Molly B; Simkin-Silverman, Laurey R; Pettee, Kelley K; Hess, Rachel; Kuller, Lewis H; Kriska, Andrea M

    2007-10-01

    After menopause, leisure physical activity (PA) levels seem to decline for reasons that are not completely understood. This study examines the associations between PA, lapses in PA, and psychosocial factors in early postmenopausal women. This cross-sectional analysis included 497 women from the Women on the Move through Activity and Nutrition study. PA was assessed with a past-year, interviewer-administered Modifiable Activity Questionnaire. Measures of activity lapses of >or= 2 wk in the past 6 months, exercise decision making, processes of change, and self-efficacy were collected along with Beck Depression Inventory, State-Trait Anxiety Inventory, Cohen Perceived Stress Scale, and Short Form-36. Mean age of participants was 56.9 yr. Compared with less active women, women with significantly higher activity levels reported greater exercise self-efficacy (r = 0.31), more frequent use of behavioral exercise processes of change (r = 0.31), greater perceived benefits for PA (r = 0.22), and better physical quality of life (r = 0.16) (all P activity lapses had higher reported activity levels than regularly active women with lapses or occasionally active women with lapses (P anxiety and depressive symptoms, and less frequent use of behavioral exercise processes of change, were associated with relapse to inactivity. Future interventions for early postmenopausal women should consider psychosocial factors when attempting to encourage and maintain higher levels of PA. Addressing and preventing PA lapses may help to achieve PA goals in this population.

  9. A resource-control account of sustained attention: evidence from mind-wandering and vigilance paradigms.

    Science.gov (United States)

    Thomson, David R; Besner, Derek; Smilek, Daniel

    2015-01-01

    Staying attentive is challenging enough when carrying out everyday tasks, such as reading or sitting through a lecture, and failures to do so can be frustrating and inconvenient. However, such lapses may even be life threatening, for example, if a pilot fails to monitor an oil-pressure gauge or if a long-haul truck driver fails to notice a car in his or her blind spot. Here, we explore two explanations of sustained-attention lapses. By one account, task monotony leads to an increasing preoccupation with internal thought (i.e., mind wandering). By another, task demands result in the depletion of information-processing resources that are needed to perform the task. A review of the sustained-attention literature suggests that neither theory, on its own, adequately explains the full range of findings. We propose a novel framework to explain why attention lapses as a function of time-on-task by combining aspects of two different theories of mind wandering: attentional resource (Smallwood & Schooler, 2006) and control failure (McVay & Kane, 2010). We then use our "resource-control" theory to explain performance decrements in sustained-attention tasks. We end by making some explicit predictions regarding mind wandering in general and sustained-attention performance in particular. © The Author(s) 2014.

  10. Memory of a drug lapse: Role of noradrenaline.

    Science.gov (United States)

    Cummins Jacklin, Erin; Boughner, Emily; Kent, Katrina; Kwiatkowski, Daniela; MacDonald, Tyler; Leri, Francesco

    2015-12-01

    Memory processes may be involved in the transition from drug lapses to relapse. This study explored the role of noradrenaline (NA) in reacquisition of place preference, an animal model of relapse that involves the updating of memories about drugs and associated stimuli. Experiments involved 7 phases: habituation, conditioning (1 mg/kg heroin and vehicle; 4 pairings each), test of conditioning (Test I), extinction (vehicle and vehicle; 4 pairings each), test of extinction (Test II), reconditioning (1 mg/kg heroin and vehicle; 1 re-pairing each), and test of reconditioning (Test III). To target memory stabilization processes, various treatments were administered post-reconditioning: systemic clonidine (0, 10, 40, 100 μg/kg; α2 adrenergic receptor agonist); intra-locus coeruleus (LC) clonidine (0, 4.5, 18 nmol); and intra-basolateral amygdala (BLA) propranolol/prazosin (0, 34/2.4 nmol; β and α1 adrenergic receptor antagonists, respectively). The effect of post-reconditioning systemic clonidine on BLA c-fos expression was also assessed. It was found that systemic clonidine dose-dependently blocked heroin reacquisition when given immediately or 4 h post-reconditioning, but not 8 h later or 4 h prior to Test III. Similar effects were observed following intra-LC clonidine infusions. Post-reconditioning systemic clonidine also blocked reacquisition of cocaine place preference (20 mg/kg). Finally, BLA c-fos expression was reduced by clonidine, and blockade of BLA β and α1 receptors prevented heroin reacquisition. These findings in rats support the hypothesis that relapse involves memory stabilization processes that can be disrupted by suppression of central NA activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Estimation of turbulence from time-lapse imagery

    Science.gov (United States)

    McCrae, Jack E.; Bose-Pillai, Santasri R.; Fiorino, Steven T.

    2017-07-01

    Atmospheric turbulence parameters are estimated for an imaging path based on time-lapse imaging results. Atmospheric turbulence causes frame-to-frame shifts of the entire image as well as parts of the image. The statistics of these shifts encode information about the turbulence strength (as characterized by Cn2, the refractive index structure function constant) along the optical path. The shift variance observed is simply proportional to the variance of the tilt of the optical field averaged over the area being tracked and averaged over the camera aperture. By presuming this turbulence follows the Kolmogorov spectrum, weighting functions, which relate the turbulence strength along the path to the shifts measured, are derived. These weighting functions peak at the camera and fall to zero at the object. The larger the area observed, the more quickly the weighting function decays. One parameter we would like to estimate is r0 (the Fried parameter or atmospheric coherence diameter.) The weighting functions derived for pixel sized or larger parts of the image all fall faster than the weighting function appropriate for estimating the spherical wave r0. If we were to presume that Cn2 is constant along the path, then an estimate for r0 could be obtained for each area tracked, but since the weighting function for r0 differs substantially from that for every realizable tracked area, it can be expected that this approach would yield a poor estimate. Instead, the weighting functions for a number of different patch sizes can be combined through the Moore-Penrose pseudoinverse to create a weighting function that yields the least-squares optimal linear combination of measurements for the estimation of r0. This approach is carried out for one example and is shown to give noisy results. A modified version of this approach that creates larger patches by averaging several smaller patches together solves this noise issue. This approach can also work to estimate other atmospheric

  12. Automated Ground-based Time-lapse Camera Monitoring of West Greenland ice sheet outlet Glaciers: Challenges and Solutions

    Science.gov (United States)

    Ahn, Y.; Box, J. E.; Balog, J.; Lewinter, A.

    2008-12-01

    Monitoring Greenland outlet glaciers using remotely sensed data has drawn a great attention in earth science communities for decades and time series analysis of sensory data has provided important variability information of glacier flow by detecting speed and thickness changes, tracking features and acquiring model input. Thanks to advancements of commercial digital camera technology and increased solid state storage, we activated automatic ground-based time-lapse camera stations with high spatial/temporal resolution in west Greenland outlet and collected one-hour interval data continuous for more than one year at some but not all sites. We believe that important information of ice dynamics are contained in these data and that terrestrial mono-/stereo-photogrammetry can provide theoretical/practical fundamentals in data processing along with digital image processing techniques. Time-lapse images over periods in west Greenland indicate various phenomenon. Problematic is rain, snow, fog, shadows, freezing of water on camera enclosure window, image over-exposure, camera motion, sensor platform drift, and fox chewing of instrument cables, and the pecking of plastic window by ravens. Other problems include: feature identification, camera orientation, image registration, feature matching in image pairs, and feature tracking. Another obstacle is that non-metric digital camera contains large distortion to be compensated for precise photogrammetric use. Further, a massive number of images need to be processed in a way that is sufficiently computationally efficient. We meet these challenges by 1) identifying problems in possible photogrammetric processes, 2) categorizing them based on feasibility, and 3) clarifying limitation and alternatives, while emphasizing displacement computation and analyzing regional/temporal variability. We experiment with mono and stereo photogrammetric techniques in the aide of automatic correlation matching for efficiently handling the enormous

  13. Predicting Smoking Lapses in the First Week of Quitting: An Ecological Momentary Assessment Study.

    Science.gov (United States)

    Bolman, Catherine; Verboon, Peter; Thewissen, Vivianne; Boonen, Viviane; Soons, Karin; Jacobs, Nele

    2017-10-24

    This study focused on lapse shortly after an attempt to quit smoking. Ecological momentary assessment (EMA) studies have mapped real-time situational factors that induce lapses in everyday life. However, the possible role of nonsmoking intention is disregarded in the dynamic context of daily life, whereas intention plays a key role in behavior change and shifts during smoking cessation. This study therefore aimed to capture the influence of intention on lapse, next to the known risk factors of negative affect, low self-efficacy, craving, positive outcome expectations towards smoking (POEs), being around smokers, and stress. It is hypothesized that scores on these factors shift during the day, especially shortly after quitting, which may induce lapse. Based on behavioral explanation models, intention is hypothesized to mediate the influence of the mentioned factors on lapse. An EMA study was conducted among 49 self-quitters in the first week of smoking cessation. Generalized Linear Mixed Model regression analyses revealed that low nonsmoking intentions, low self-efficacy, and being around smokers (estimates were, respectively, -0.303, -0.331, and 2.083) predicted lapse. Nonsmoking intention partially mediated the influence of self-efficacy on lapse. Nonsmoking intention was predicted by not being around smokers, high self-efficacy, and low POEs (estimates were, respectively, -0.353, 0.293, and -0.072). This small-scale EMA study confirms the importance of nonsmoking intention on lapse, next to self-efficacy and being around smokers. It adds insights into the mediating role of intention on the relationship between self-efficacy and lapse, and into the predictors of nonsmoking intention.This is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used

  14. Advances in interpretation of subsurface processes with time-lapse electrical imaging

    Science.gov (United States)

    Singha, Kaminit; Day-Lewis, Frederick D.; Johnson, Tim B.; Slater, Lee D.

    2015-01-01

    Electrical geophysical methods, including electrical resistivity, time-domain induced polarization, and complex resistivity, have become commonly used to image the near subsurface. Here, we outline their utility for time-lapse imaging of hydrological, geochemical, and biogeochemical processes, focusing on new instrumentation, processing, and analysis techniques specific to monitoring. We review data collection procedures, parameters measured, and petrophysical relationships and then outline the state of the science with respect to inversion methodologies, including coupled inversion. We conclude by highlighting recent research focused on innovative applications of time-lapse imaging in hydrology, biology, ecology, and geochemistry, among other areas of interest.

  15. A randomized clinical trial comparing embryo culture in a conventional incubator with a time-lapse incubator

    DEFF Research Database (Denmark)

    Kirkegaard, Kirstine; Hindkjaer, Johnny Juhl; Grøndahl, Marie Louise

    2012-01-01

    Time-lapse monitoring allows for a flexible embryo evaluation and potentially provides new dynamic markers of embryo competence. Before introducing time-lapse monitoring in a clinical setting, the safety of the instrument must be properly documented. Accordingly, the aim of this study was to eval...

  16. Neuroticism and the mental noise hypothesis: Relationships to lapses of attention and slips of action in everyday life

    OpenAIRE

    HAGEN C. FLEHMIG; MICHAEL STEINBORN; ROBERT LANGNER; KARL WESTHOFF

    2007-01-01

    We investigated the relationship between neuroticism and cognitive failure liability in everyday-life situations. Previous research (e.g., Robinson & Tamir, 2005; Robinson, Wilkowski & Meier, 2006) reported a positive association between the trait of neuroticism (N) and fluctuations in mental efficiency when performing elementary cognitive operations. High-N individuals were proposed to be characterized by increased noise within information processing from perception to action. To further exa...

  17. Neuroticism and the mental noise hypothesis: Relationships to lapses of attention and slips of action in everyday life

    Directory of Open Access Journals (Sweden)

    HAGEN C. FLEHMIG

    2007-12-01

    Full Text Available We investigated the relationship between neuroticism and cognitive failure liability in everyday-life situations. Previous research (e.g., Robinson & Tamir, 2005; Robinson, Wilkowski & Meier, 2006 reported a positive association between the trait of neuroticism (N and fluctuations in mental efficiency when performing elementary cognitive operations. High-N individuals were proposed to be characterized by increased noise within information processing from perception to action. To further examine this relationship, we collected self-report data from 222 individuals, measuring N via the Eysenck Personality Questionnaire and the related construct of Behavioural Inhibition System sensitivity via the BIS/BAS scales, and assessing cognitive failure liability via the Cognitive Failures Questionnaire (CFQ. The results revealed positive correlations between N and general cognitive failure liability, providing further support for the mental noise hypothesis. A more detailed investigation of CFQ subscales (Meiran et al., 1994 yielded a specific pattern, with the strongest correlation between N and the CFQ–Unintended Activation subscale (r = .40; p < .01. This suggests that high-N individuals preferably commit cognitive failures due to intrusions of task-irrelevant cognitions from associative memory.

  18. Construction of an 8-mm time-lapse camera for biological research

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers the construction of an 8mm camera for biological research. A time-lapse camera for use in biological research can be constructed from a super 8-mm...

  19. Inter and intra-observer variability of time-lapse annotations

    DEFF Research Database (Denmark)

    Sundvall Germeys, Linda Karin M; Ingerslev, Hans Jakob; Knudsen, Ulla Breth

    Study question: How consistent is the time-lapse annotation of dynamic and static morphologic parameters of embryo development, within and between observers? Summary answer: The assessment of dynamic parameters is characterized by almost perfect agreement within and between observers. What is kno...

  20. 3D lens-free time-lapse microscopy for 3D cell culture

    Science.gov (United States)

    Berdeu, Anthony; Momey, Fabien; Laperrousaz, Bastien; Bordy, Thomas; Gidrol, Xavier; Dinten, Jean-Marc; Picollet-D'hahan, Nathalie; Allier, Cédric

    2017-07-01

    We propose a new imaging platform based on lens-free time-lapse microscopy for 3D cell culture and its dedicated algorithm lying on a fully 3D regularized inverse problem approach. First 3D+t results are presented

  1. Exploiting the airwave for time-lapse reservoir monitoring with CSEM on land

    NARCIS (Netherlands)

    Wirianto, M.; Mulder, W.A.; Slob, E.C.

    2011-01-01

    In the application of controlled source electromagnetics for reservoir monitoring on land, repeatability errors in the source will mask the time-lapse signal due to hydrocarbon production when recording surface data close to the source. We demonstrate that at larger distances, the airwave will still

  2. MathLTWA: Multiple lapse time window analysis using Wolfram Mathematica 7

    Science.gov (United States)

    Del Pezzo, Edoardo; Bianco, Francesca

    2010-10-01

    The MATHCAD 2000 professional code to perform the Multiple Lapse Time Analysis (MLTWA) has been revised and rewritten in MATHEMATICA 7. The new code contains two new procedures to find the minimum of the misfit function between observation and model and a new example of application to real data from Chamoli earthquake aftershock sequence.

  3. Lapse of time effects on tax evasion in an agent-based econophysics model

    Science.gov (United States)

    Seibold, Götz; Pickhardt, Michael

    2013-05-01

    We investigate an inhomogeneous Ising model in the context of tax evasion dynamics where different types of agents are parameterized via local temperatures and magnetic fields. In particular, we analyze the impact of lapse of time effects (i.e. backauditing) and endogenously determined penalty rates on tax compliance. Both features contribute to a microfoundation of agent-based econophysics models of tax evasion.

  4. Time-Lapse and Slow-Motion Tracking of Temperature Changes: Response Time of a Thermometer

    Science.gov (United States)

    Moggio, L.; Onorato, P.; Gratton, L. M.; Oss, S.

    2017-01-01

    We propose the use of a smartphone based time-lapse and slow-motion video techniques together with tracking analysis as valuable tools for investigating thermal processes such as the response time of a thermometer. The two simple experimental activities presented here, suitable also for high school and undergraduate students, allow one to measure…

  5. The Atmospheric Lapse Rates in a Tropical Regime: Nigeria (LAT. 05

    African Journals Online (AJOL)

    These preliminary results suggest that the lapse rates are higher in Kano than in Lagos (an average of 10% larger in the dry months and 23% in the wet months) for two atmospheric columns (surface to 500mb and 400-250mb), while the reverse was the case for the atmospheric slice 500-400mb where Lagos exceeds by ...

  6. Rapid antimicrobial susceptibility testing of clinical isolates by digital time-lapse microscopy

    DEFF Research Database (Denmark)

    Fredborg, M; Rosenvinge, F S; Spillum, E

    2015-01-01

    Rapid antimicrobial susceptibility testing (AST) is essential for early and appropriate therapy. Methods with short detection time enabling same-day treatment optimisation are highly favourable. In this study, we evaluated the potential of a digital time-lapse microscope system, the oCelloScope s...

  7. The Association Between Peer and Self-Assessments and Professionalism Lapses Among Medical Students.

    Science.gov (United States)

    Hoffman, Leslie A; Shew, Ronald L; Vu, T Robert; Brokaw, James J; Frankel, Richard M

    2017-06-01

    Peer and self-assessments are widely used to assess professionalism during medical school as part of a multisource feedback model. The purpose of this study was to examine the associations between peer and self-assessments and professionalism lapses at a large medical school. A retrospective case-control study design was used to compare peer and self-assessment scores from Years 1 to 3 of medical school for students who had been cited for professionalism lapses during medical school (case group; n = 78) with those of a randomly selected control group ( n = 230). Students in the case group had significantly lower peer assessment scores than students in the control group during all 3 years. Year 3 peer assessment scores showed the greatest difference (cases = 7.81 ± 0.65, controls = 8.22 ± 0.34, p peer assessment scores were also significantly more likely to have been cited for a professionalism lapse (odds ratio = 6.25, 95% CI [3.13, 11.11], p peer assessments of professionalism, which may be useful to help identify students who may be at risk for professionalism lapses during medical school.

  8. Latest time-lapse seismic data from Sleipner yield new insights into CO2 plume development

    NARCIS (Netherlands)

    Chadwick, R.A.; Noy, D.; Arts, R.; Eiken, O.

    2009-01-01

    Since its inception in 1996, the CO2 injection operation at Sleipner has been monitored by 3D time-lapse seismic surveys. Striking images of the CO2 plume have been obtained, showing a multi-tier feature of high reflectivity, interpreted as arising from a number of thin layers of CO2 trapped beneath

  9. Determination of Optimum Frame Rates for Observation of Construction Operations from Time-Lapse Movies

    Directory of Open Access Journals (Sweden)

    Y. M. Ibrahim

    2012-07-01

    Full Text Available Construction professionals have been using time-lapse movies in monitoring construction operations. However, some amount of detail is always lost in the interval between two consecutive frames in a time-lapse movie. This poses the question: By how much can the frame rate be lowered from the standard 30fps (frames per second to allow for the accurate observation of construction operations from a time-lapse movie? This paper addresses the problem by establishing the optimum frame rates for observation of activities related to mortar mixing and block handling. The activities were first recorded at the standard rate of 30fps. Using the Adobe Premier Pro video editing software, the records were then segregated into still images from which 15 different time-lapse movies of various time intervals were generated. The movies were then shown to 25 Construction Managers. A structured questionnaire was employed to capture the level of accuracy with which Construction Managers could interpret the job site situation from each movie. The results suggest that 1fpm (frame per minute is sufficient for the accurate tracking of labourers involved in mortar mixing while 1 frame in every 20 seconds is sufficient for accurate identification of number of cement bags used. However, for tracking number of blocks off-loaded, and those damaged, 1 frame in every 2 seconds is required.

  10. Lapse rate characteristics in ice clouds inferred from GPS RO and CloudSat observations

    Science.gov (United States)

    Yang, S.; Zou, X.

    2017-11-01

    GPS Radio Occultation (RO) cloudy profiles during a seven-year period from 2007 to 2013 over the globe are firstly selected and grouped into four types of ice clouds (e.g., nimbostratus, deep convective, cirrus, altostratus) based on collocated CloudSat data. Vertical temperature profiles within ice clouds below - 20 °C are then retrieved from GPS RO refractivity observations, in which the vertical profiles of ice water content required by the forward model of refractivity are obtained from CloudSat retrievals of ice water content. Vertical distributions of relative humidity and lapse rate within clouds are finally examined in terms of their occurrences, mean values and standard deviations. It is found that ice clouds have preferred values of relative humidity and lapse rate depending on cloud types and altitudes. Most altostratus ice clouds are located between 4 and 8 km with relative humidity between 55 and 75%. The cirrus clouds have a relative humidity around 60% and are located mostly above 6 km to as high as 13 km. Difference from cirrus and altostratus ice clouds, nimbostratus ice clouds that occur mostly in polar regions are found at all altitudes below 10 km with a relative humidity decreasing linearly from about 90% near the surface to about 60% around 6 km. Within deep convective ice clouds, the relative humidity also decreases linearly from about 100% around 2.5 km to about 60% around 9 km. The lapse rate slightly increases with altitude and its value ranges between 5 and 8 °C km- 1 within nimbostratus, deep convective and altostratus ice clouds. The lapse rate within cirrus clouds varies from 6 °C km- 1 to 9 °C km- 1. Vertical variations of the lapse rate derived from GPS RO cloudy retrievals compared favorably to those derived from radiosonde profiles. Both showed that the mean lapse rate increases with altitude from about 5 °C km- 1 around 3 km to about 7 °C km- 1 around 7 km, and the standard deviations are much smaller than the mean lapse

  11. Time-lapse monitoring of localized changes within heterogeneous media with scattered waves

    Science.gov (United States)

    Chinaemerem, Kanu

    Time-lapse monitoring of geological and mechanical media has been the focus of various studies over the past four decades because of the information that the inferred changes within the medium provides insight into the dynamic characteristics of the medium. Time-lapse changes within a medium can be used to characterize the temporal evolution of the medium, evaluate the forces driving the changes within the medium and make predictions on the future state of the monitored medium. The detectability of the changes within a material depends on the characteristics of the change to be imaged, the sensitivity of the monitoring data to the change, and the time-lapse monitoring parameters such as the monitoring source-receiver array and the spectral content of the monitoring waves. Various time-lapse monitoring tools have been used to monitor changes within media ranging from the earth's surface to tumors within the human body. These monitoring tools include the use of 4D active surveys were an imprint of the change within the medium is extracted from the time-lapse surveys and the use of interferometric techniques that use singly or multiply scattered waves. My major goal in this study is to image and localize changes present within a scattering medium using time-lapse multiply scattered waves generated within the monitored medium. The changes to be imaged are generally localized in space. This work is an extension of coda wave interferometry. Coda wave interferometry focuses on the identification and extraction of average velocity change occurring within a scattering medium. Due to the non-linear characteristics of multiply scattered waves and limited information of the origin of the multiply scattered waves, coda wave interferometry resolves the average velocity change within the scattering medium with no or limited indication of the location of the change. In this study, I demonstrate that time-lapse changes can be imaged and localized within scattering media using

  12. Enhancing attention in neurodegenerative diseases: current therapies and future directions

    Directory of Open Access Journals (Sweden)

    Sharma Kanchan

    2016-01-01

    Full Text Available We all experience at least occasional lapses in attention but in some neurological conditions, loss of attention is pervasive and debilitating. Treating deficits in attention first requires an understanding of the neurobiology of attention, which we now understand to be a set of different cognitive processes. Cholinesterase inhibitors are already established as effective attentional enhancers used in the treatment of certain dementias. Other stimulant agents such as modafanil, amphetamine and methylphenidate have demonstrated limited success in healthy individuals where attention is already optimal and clinical trials in patients with neurological disease are sparse. Dietary and lifestyle changes are gaining increasing prominence, as are experimental treatments such as deep brain stimulation and transcranial magnetic stimulation. As the therapeutic arsenal widens, clinicians will be able to match specific treatments to selective deficits in attention, giving patients a tailored management plan. Here we review common diseases that impair attention and emphasise how an understanding of attentional processing within the brain might lead to improved therapeutic strategies.

  13. Formation of medical student professional identity: categorizing lapses of professionalism, and the learning environment.

    Science.gov (United States)

    Hendelman, Walter; Byszewski, Anna

    2014-07-09

    Acquiring the values of medical professionalism has become a critical issue in medical education. The purpose of this study was to identify lapses in professionalism witnessed by medical students during their four year MD curriculum, and to categorize, from the students' perspective, who was responsible and the settings in which these occurred. An electronic survey, developed by faculty and medical students, was sent to all students with two email reminders. It included quantitative responses and some open-ended opportunities for comments. All analyses were performed with SAS version 9.1. The response rate was 45.6% (255 of 559 students) for all four years of the medical school curriculum. Thirty six percent of students had witnessed or been part of an exemplary demonstration of professionalism; 64% responded that they had witnessed a lapse of professionalism. At the pre-clerkship level, the most frequent lapses involved students: arrogance (42.2%), impairment (24.2%), followed by cultural or religious insensitivity (20.5%). At the clerkship level of training, where students are exposed to real clinical situations, the lapses involved primarily faculty (including preceptor and clinician) or other staff; these included arrogance (55.3%), breach of confidentiality (28.3%), and cultural or religious insensitivity (26.6%); impairment involved mostly students (25.5%). These findings are analyzed from the perspective of role modeling by faculty and in the context of the learning environment. Medical students witnessed a lapse of professionalism involving both fellow students as well as faculty and administrative staff, in several domains. Results from this study emphasize the importance of role modeling and the need for faculty development, to improve the learning environment. This study adds to the limited emerging literature on the forces that influence medical student professional identity formation.

  14. Formation of medical student professional identity: categorizing lapses of professionalism, and the learning environment

    Science.gov (United States)

    2014-01-01

    Background Acquiring the values of medical professionalism has become a critical issue in medical education. The purpose of this study was to identify lapses in professionalism witnessed by medical students during their four year MD curriculum, and to categorize, from the students’ perspective, who was responsible and the settings in which these occurred. Methods An electronic survey, developed by faculty and medical students, was sent to all students with two email reminders. It included quantitative responses and some open-ended opportunities for comments. All analyses were performed with SAS version 9.1. Results The response rate was 45.6% (255 of 559 students) for all four years of the medical school curriculum. Thirty six percent of students had witnessed or been part of an exemplary demonstration of professionalism; 64% responded that they had witnessed a lapse of professionalism. At the pre-clerkship level, the most frequent lapses involved students: arrogance (42.2%), impairment (24.2%), followed by cultural or religious insensitivity (20.5%). At the clerkship level of training, where students are exposed to real clinical situations, the lapses involved primarily faculty (including preceptor and clinician) or other staff; these included arrogance (55.3%), breach of confidentiality (28.3%), and cultural or religious insensitivity (26.6%); impairment involved mostly students (25.5%). These findings are analyzed from the perspective of role modeling by faculty and in the context of the learning environment. Conclusions Medical students witnessed a lapse of professionalism involving both fellow students as well as faculty and administrative staff, in several domains. Results from this study emphasize the importance of role modeling and the need for faculty development, to improve the learning environment. This study adds to the limited emerging literature on the forces that influence medical student professional identity formation. PMID:25004924

  15. Developing an EEG based On-line Closed-loop Lapse Detection and Mitigation System

    Directory of Open Access Journals (Sweden)

    Yu-Te eWang

    2014-10-01

    Full Text Available In America, sixty percent of adults reported that they have driven a motor vehicle while feeling drowsy, and at least 15-20% of fatal car accidents are fatigue-related. This study translates previous laboratory-oriented neurophysiological research to design, develop, and test an On-line Closed-loop Lapse Detection and Mitigation (OCLDM System featuring a mobile wireless dry-sensor EEG headgear and a cell-phone based real-time EEG processing platform. Eleven subjects participated in an event-related lane-keeping task, in which they were instructed to manipulate a randomly deviated, fixed-speed cruising car on a 4-lane highway. This was simulated in a 1st person view with an 8-screen and 8-projector immersive virtual-realty environment. When the subjects experienced lapses or failed to respond to events during the experiment, auditory feedback was delivered to rectify the performance decrements. However, the arousing auditory signals were not always effective. The EEG spectra exhibited statistically significant differences between effective and ineffective arousing signals, suggesting that EEG spectra could be used as a countermeasure of the efficacy of arousing signals. In this on-line pilot study, the proposed OCLDM System was able to continuously detect EEG signatures of fatigue, deliver arousing feedback to subjects suffering momentary cognitive lapses, and assess the efficacy of the feedback in near real-time to rectify cognitive lapses. The on-line testing results of the OCLDM System validated the efficacy of the arousing signals in improving subjects' response times to the subsequent lane-departure events. This study may lead to a practical on-line lapse detection and mitigation system in real-world environments.

  16. Using Intensive Longitudinal Data Collected via Mobile Phone to Detect Imminent Lapse in Smokers Undergoing a Scheduled Quit Attempt.

    Science.gov (United States)

    Businelle, Michael S; Ma, Ping; Kendzor, Darla E; Frank, Summer G; Wetter, David W; Vidrine, Damon J

    2016-10-17

    Mobile phone‒based real-time ecological momentary assessments (EMAs) have been used to record health risk behaviors, and antecedents to those behaviors, as they occur in near real time. The objective of this study was to determine if intensive longitudinal data, collected via mobile phone, could be used to identify imminent risk for smoking lapse among socioeconomically disadvantaged smokers seeking smoking cessation treatment. Participants were recruited into a randomized controlled smoking cessation trial at an urban safety-net hospital tobacco cessation clinic. All participants completed in-person EMAs on mobile phones provided by the study. The presence of six commonly cited lapse risk variables (ie, urge to smoke, stress, recent alcohol consumption, interaction with someone smoking, cessation motivation, and cigarette availability) collected during 2152 prompted or self-initiated postcessation EMAs was examined to determine whether the number of lapse risk factors was greater when lapse was imminent (ie, within 4 hours) than when lapse was not imminent. Various strategies were used to weight variables in efforts to improve the predictive utility of the lapse risk estimator. Participants (N=92) were mostly female (52/92, 57%), minority (65/92, 71%), 51.9 (SD 7.4) years old, and smoked 18.0 (SD 8.5) cigarettes per day. EMA data indicated significantly higher urges (P=.01), stress (P=.002), alcohol consumption (Pweighting lapse risk variables resulted in an improved risk estimator (weighted area=0.76 vs unweighted area=0.72, P<.004). Specifically, 80% (42/52) of all participants who lapsed had at least one EMA with a lapse risk score above the cut-off within 4 hours of their first lapse. Real-time estimation of smoking lapse risk is feasible and may pave the way for development of mobile phone‒based smoking cessation treatments that automatically tailor treatment content in real time based on presence of specific lapse triggers. Interventions that identify

  17. Using Digital Time-Lapse Videos to Teach Geomorphic Processes to Undergraduates

    Science.gov (United States)

    Clark, D. H.; Linneman, S. R.; Fuller, J.

    2004-12-01

    We demonstrate the use of relatively low-cost, computer-based digital imagery to create time-lapse videos of two distinct geomorphic processes in order to help students grasp the significance of the rates, styles, and temporal dependence of geologic phenomena. Student interviews indicate that such videos help them to understand the relationship between processes and landform development. Time-lapse videos have been used extensively in some sciences (e.g., biology - http://sbcf.iu.edu/goodpract/hangarter.html, meteorology - http://www.apple.com/education/hed/aua0101s/meteor/, chemistry - http://www.chem.yorku.ca/profs/hempsted/chemed/home.html) to demonstrate gradual processes that are difficult for many students to visualize. Most geologic processes are slower still, and are consequently even more difficult for students to grasp, yet time-lapse videos are rarely used in earth science classrooms. The advent of inexpensive web-cams and computers provides a new means to explore the temporal dimension of earth surface processes. To test the use of time-lapse videos in geoscience education, we are developing time-lapse movies that record the evolution of two landforms: a stream-table delta and a large, natural, active landslide. The former involves well-known processes in a controlled, repeatable laboratory experiment, whereas the latter tracks the developing dynamics of an otherwise poorly understood slope failure. The stream-table delta is small and grows in ca. 2 days; we capture a frame on an overhead web-cam every 3 minutes. Before seeing the video, students are asked to hypothesize how the delta will grow through time. The final time-lapse video, ca. 20-80 MB, elegantly shows channel migration, progradation rates, and formation of major geomorphic elements (topset, foreset, bottomset beds). The web-cam can also be "zoomed-in" to show smaller-scale processes, such as bedload transfer, and foreset slumping. Post-lab tests and interviews with students indicate that

  18. The Attention Cascade Model and Attentional Blink

    Science.gov (United States)

    Shih, Shui-I

    2008-01-01

    An attention cascade model is proposed to account for attentional blinks in rapid serial visual presentation (RSVP) of stimuli. Data were collected using single characters in a single RSVP stream at 10 Hz [Shih, S., & Reeves, A. (2007). "Attentional capture in rapid serial visual presentation." "Spatial Vision", 20(4), 301-315], and single words,…

  19. Difficulties with Emotion Regulation and Psychopathology Interact to Predict Early Smoking Cessation Lapse.

    Science.gov (United States)

    Farris, Samantha G; Zvolensky, Michael J; Schmidt, Norman B

    2016-06-01

    There is little knowledge about how emotion regulation difficulties interplay with psychopathology in terms of smoking cessation. Participants (n = 250; 53.2 % female, Mage = 39.5, SD = 13.85) were community-recruited daily smokers (≥8 cigarettes per day) who self-reported motivation to quit smoking; 38.8 % of the sample met criteria for a current (past 12-month) psychological disorder. Emotion regulation deficits were assessed pre-quit using the Difficulties with Emotion Regulation Scale (DERS; Gratz and Roemer in J Psychopathol Behav Assess 26(1):41-54, 2004) and smoking behavior in the 28 days post-quit was assessed using the Timeline Follow-Back (TLFB; Sobell and Sobell in Measuring alcohol consumption: psychosocial and biochemical methods. Humana Press, Totowa, 1992). A Cox proportional-hazard regression analysis was used to model the effects of past-year psychopathology, DERS (total score), and their interaction, in terms of time to lapse post-quit day. After adjusting for the effects of gender, age, pre-quit level of nicotine dependence, and treatment condition, the model revealed a non-significant effect of past-year psychopathology (OR = 1.14, CI95 % = 0.82-1.61) and difficulties with emotion regulation (OR = 1.01, CI95 % = 1.00-1.01) on likelihood of lapse rate. However, the interactive effect of psychopathology status and difficulties with emotion regulation was significant (OR = 0.98, CI95 % = 0.97-0.99). Specifically, there was a significant conditional effect of psychopathology status on lapse rate likelihood at low, but not high, levels of emotion regulation difficulties. Plots of the cumulative survival functions indicated that for smokers without a past-year psychological disorder, those with lower DERS scores relative to elevated DERS scores had significantly lower likelihood of early smoking lapse, whereas for smokers with past-year psychopathology, DERS scores did not differentially impact lapse rate likelihood. Smokers with emotion regulation

  20. The influence of large-scale lapse-rate changes on the European summer climate

    Science.gov (United States)

    Kröner, Nico; Kotlarski, Sven; Lüthi, Daniel; Fischer, Erich; Schär, Christoph

    2015-04-01

    The record-breaking summer heatwaves in 2003 and 2010 had large socio-economic impacts. Over recent decades a strong increase in European summer temperatures has been observed especially in the uppermost percentiles. Future climate projections provide strong evidence for this trend to continue. However, the processes driving the observed and projected changes in European summer climate and climate variability are not fully understood. Different mechanisms were proposed including changes in soil moisture regime, cloud-cover changes or altered large-scale circulation patterns. So far, only few studies considered the regional feedbacks of a large-scale lapse-rate change. In the present study we apply the surrogate climate change technique to regional climate model simulations to disentangle this lapse-rate effect from other factors. One aspect considered is the pronounced south-north gradient in projected European summer warming, which has an opposite latitudinal direction in comparison to annual-mean large-scale conditions. The basic idea of the surrogate approach is to apply a large-scale warming to the lateral boundary conditions of a present-day RCM simulation, while maintaining relative humidity (and thus implicitly increasing the specific moisture content). Two runs of the regional climate model COSMO-CLM with a grid spacing of approximately 50 km (EURO-CORDEX EUR-44 setup) are used as references: a regular control (1971-2000, CTRL) and scenario (2070-2099, SCEN) experiment driven by the global climate model MPI-ESM-LR and assuming the RCP8.5 greenhouse gas emission scenario. In a first experiment the warming (as estimated from SCEN-CTRL) is added to the CTRL simulation as a vertically and horizontally homogeneous warming and in a second case assumed to be a function of height, thereby accounting for lapse rate changes. Comparing these two cases allows to quantify the effect of a large-scale lapse rate change and to isolate the corresponding physical mechanisms

  1. Time-Lapse Monitoring of Subsurface Fluid Flow using Parsimonious Seismic Interferometry

    KAUST Repository

    Hanafy, Sherif

    2017-04-21

    A typical small-scale seismic survey (such as 240 shot gathers) takes at least 16 working hours to be completed, which is a major obstacle in case of time-lapse monitoring experiments. This is especially true if the subject that needs to be monitored is rapidly changing. In this work, we will discuss how to decrease the recording time from 16 working hours to less than one hour of recording. Here, the virtual data has the same accuracy as the conventional data. We validate the efficacy of parsimonious seismic interferometry with the time-lapse mentoring idea with field examples, where we were able to record 30 different data sets within a 2-hour period. The recorded data are then processed to generate 30 snapshots that shows the spread of water from the ground surface down to a few meters.

  2. Near-surface temperature lapse rates in a mountainous catchment in the Chilean Andes

    Science.gov (United States)

    Ayala; Schauwecker, S.; Pellicciotti, F.; McPhee, J. P.

    2011-12-01

    In mountainous areas, and in the Chilean Andes in particular, the irregular and sparse distribution of recording stations resolves insufficiently the variability of climatic factors such as precipitation, temperature and relative humidity. Assumptions about air temperature variability in space and time have a strong effect on the performance of hydrologic models that represent snow processes such as accumulation and ablation. These processes have large diurnal variations, and assumptions that average over longer time periods (days, weeks or months) may reduce the predictive capacity of these models under different climatic conditions from those for which they were calibrated. They also introduce large uncertainties when such models are used to predict processes with strong subdiurnal variability such as snowmelt dynamics. In many applications and modeling exercises, temperature is assumed to decrease linearly with elevation, using the free-air moist adiabatic lapse rate (MALR: 0.0065°C/m). Little evidence is provided for this assumption, however, and recent studies have shown that use of lapse rates that are uniform in space and constant in time is not appropriate. To explore the validity of this approach, near-surface (2 m) lapse rates were calculated and analyzed at different temporal resolution, based on a new data set of spatially distributed temperature sensors setup in a high elevation catchment of the dry Andes of Central Chile (approx. 33°S). Five minutes temperature data were collected between January 2011 and April 2011 in the Ojos de Agua catchment, using two Automatic Weather Stations (AWSs) and 13 T-loggers (Hobo H8 Pro Temp with external data logger), ranging in altitude from 2230 to 3590 m.s.l.. The entire catchment was snow free during our experiment. We use this unique data set to understand the main controls over temperature variability in time and space, and test whether lapse rates can be used to describe the spatial variations of air

  3. On the structure of atmospheric warming in models and observations: Implications for the lapse rate feedback

    Science.gov (United States)

    Po-Chedley, Stephen D.

    indicate that the prescribed ozone and stratospheric aerosol forcings do not effect T24/TLT amplification in models. On the other hand, model parameterizations for convection and microphysics and, to a lesser degree, uncertainty in the prescribed SST dataset can influence model amplification behavior and bring models into closer accord with observations. In all, significant T24/TLT discrepancies between models and observations remain, but may be reduced with improved model parameterizations. An underlying motivation for understanding the structure of atmospheric warming is that it is responsible for a large negative lapse rate feedback in future climate simulations. To understand factors that control the global lapse rate feedback across models, we use principal component analysis to find the modes of variability that best explain variance in the local lapse rate feedback. We find that models exhibit marked variability in the lapse rate feedback in the southern hemisphere extratropics. This mode is strongly correlated with the global average lapse rate feedback and is largely a function of the competing influence of tropical and Antarctic surface warming. We show that muted southern ocean sea surface warming and the non-local influence of tropical surface warming contributes to a highly variable lapse rate feedback in the sub-Antarctic across models. This behavior is dissimilar to northern hemisphere high latitudes, which are characterized by strong Arctic amplification and a relatively uniform local lapse rate feedback across GCMs. Climatological Antarctic sea ice extent influences Antarctic warming and, as a result, influences both the meridional profile of warming in the southern hemisphere and the global lapse rate feedback.

  4. Calixarenes and cations: a time-lapse photography of the big-bang.

    Science.gov (United States)

    Casnati, Alessandro

    2013-08-07

    The outstanding cation complexation properties emerging from the pioneering studies on calixarene ligands during a five-year period in the early 1980s triggered a big-bang burst of publications on such macrocycles that is still lasting at a distance of more than 30 years. A time-lapse photography of this timeframe is proposed which allows the readers to pinpoint the contributions of the different research groups.

  5. Probabilistic 3-D time-lapse inversion of magnetotelluric data: application to an enhanced geothermal system

    OpenAIRE

    Rosas-Carbajal, M; N. Linde; Peacock, J.; Zyserman, F. I.; Kalscheuer, Thomas; Thiel, S.

    2015-01-01

    Surface-based monitoring of mass transfer caused by injections and extractions in deep boreholes is crucial to maximize oil, gas and geothermal production. Inductive electromagnetic methods, such as magnetotellurics, are appealing for these applications due to their large penetration depths and sensitivity to changes in fluid conductivity and fracture connectivity. In this work, we propose a 3-D Markov chain Monte Carlo inversion of time-lapse magnetotelluric data to image mass transfer follo...

  6. 3D Time-lapse Imaging and Quantification of Mitochondrial Dynamics

    OpenAIRE

    Sison, Miguel; Chakrabortty, Sabyasachi; Extermann, J?r?me; Nahas, Amir; James Marchand, Paul; Lopez, Antonio; Weil, Tanja; Lasser, Theo

    2017-01-01

    We present a 3D time-lapse imaging method for monitoring mitochondrial dynamics in living HeLa cells based on photothermal optical coherence microscopy and using novel surface functionalization of gold nanoparticles. The biocompatible protein-based biopolymer coating contains multiple functional groups which impart better cellular uptake and mitochondria targeting efficiency. The high stability of the gold nanoparticles allows continuous imaging over an extended time up to 3000 seconds withou...

  7. Imaging Hydrological Processes in Headwater Riparian Seeps with Time-Lapse Electrical Resistivity.

    Science.gov (United States)

    Williams, Mark R; Buda, Anthony R; Singha, Kamini; Folmar, Gordon J; Elliott, Herschel A; Schmidt, John P

    2017-01-01

    Delineating hydrologic and pedogenic factors influencing groundwater flow in riparian zones is central in understanding pathways of water and nutrient transport. In this study, we combined two-dimensional time-lapse electrical resistivity imaging (ERI) (depth of investigation approximately 2 m) with hydrometric monitoring to examine hydrological processes in the riparian area of FD-36, a small (0.4 km(2) ) agricultural headwater basin in the Valley and Ridge region of east-central Pennsylvania. We selected two contrasting study sites, including a seep with groundwater discharge and an adjacent area lacking such seepage. Both sites were underlain by a fragipan at 0.6 m. We then monitored changes in electrical resistivity, shallow groundwater, and nitrate-N concentrations as a series of storms transitioned the landscape from dry to wet conditions. Time-lapse ERI revealed different resistivity patterns between seep and non-seep areas during the study period. Notably, the seep displayed strong resistivity reductions (∼60%) along a vertically aligned region of the soil profile, which coincided with strong upward hydraulic gradients recorded in a grid of nested piezometers (0.2- and 0.6-m depth). These patterns suggested a hydraulic connection between the seep and the nitrate-rich shallow groundwater system below the fragipan, which enabled groundwater and associated nitrate-N to discharge through the fragipan to the surface. In contrast, time-lapse ERI indicated no such connections in the non-seep area, with infiltrated rainwater presumably perched above the fragipan. Results highlight the value of pairing time-lapse ERI with hydrometric and water quality monitoring to illuminate possible groundwater and nutrient flow pathways to seeps in headwater riparian areas. © 2016, National Ground Water Association.

  8. Peeter Kreitzberg : võtame vaestelt lapsed ära! / Peeter Kreitzberg ; interv. Helen Urbanik

    Index Scriptorium Estoniae

    Kreitzberg, Peeter, 1948-2011

    2001-01-01

    Endine haridusminister tuli märtsi keskel konverentsil "Teine võimalus hariduses" välja ettepanekuga, et lastele peaks koolis käimine olema kohustuslik 18. eluaastani, riigi pansionidesse ja internaatidesse tuleks panna need lapsed, kelle pered ei jaksa neid üleval pidada. Autori täiendus 3. mai Eesti Ekspressi kirjade rubriigis (lk. A6) pealkirja all: Pakkusin vanematele võimalust, mitte vaeste laste konfiskeerimist. Autor: Keskerakond. Parlamendisaadik

  9. An instrumented sample holder for time-lapse microtomography measurements of snow under advective airflow

    Directory of Open Access Journals (Sweden)

    P. P. Ebner

    2014-09-01

    Full Text Available An instrumented sample holder was developed for time-lapse microtomography of snow samples to enable in situ nondestructive spatial and temporal measurements under controlled advective airflows, temperature gradients, and air humidities. The design was aided by computational fluid dynamics simulations to evaluate the airflow uniformity across the snow sample. Morphological and mass transport properties were evaluated during a 4-day test run. This instrument allows the experimental characterization of metamorphism of snow undergoing structural changes with time.

  10. Unscented Kalman filter assimilation of time-lapse self-potential data for monitoring solute transport

    Science.gov (United States)

    Cui, Yi-an; Liu, Lanbo; Zhu, Xiaoxiong

    2017-08-01

    Monitoring the extent and evolution of contaminant plumes in local and regional groundwater systems from existing landfills is critical in contamination control and remediation. The self-potential survey is an efficient and economical nondestructive geophysical technique that can be used to investigate underground contaminant plumes. Based on the unscented transform, we have built a Kalman filtering cycle to conduct time-lapse data assimilation for monitoring the transport of solute based on the solute transport experiment using a bench-scale physical model. The data assimilation was formed by modeling the evolution based on the random walk model and observation correcting based on the self-potential forward. Thus, monitoring self-potential data can be inverted by the data assimilation technique. As a result, we can reconstruct the dynamic process of the contaminant plume instead of using traditional frame-to-frame static inversion, which may cause inversion artifacts. The data assimilation inversion algorithm was evaluated through noise-added synthetic time-lapse self-potential data. The result of the numerical experiment shows validity, accuracy and tolerance to the noise of the dynamic inversion. To validate the proposed algorithm, we conducted a scaled-down sandbox self-potential observation experiment to generate time-lapse data that closely mimics the real-world contaminant monitoring setup. The results of physical experiments support the idea that the data assimilation method is a potentially useful approach for characterizing the transport of contamination plumes using the unscented Kalman filter (UKF) data assimilation technique applied to field time-lapse self-potential data.

  11. Comparing sleep-loss sleepiness and sleep inertia: lapses make the difference.

    Science.gov (United States)

    Miccoli, Laura; Versace, Francesco; Koterle, Sara; Cavallero, Corrado

    2008-09-01

    To compare the behavioral effects of sleep-loss sleepiness (performance impairment due to sleep loss) and sleep inertia (period of impaired performance that follows awakening), mean response latencies and number of lapses from a visual simple reaction-time task were analyzed. Three experimental conditions were designed to manipulate sleepiness and sleep-inertia levels: uninterrupted sleep, partial sleep reduction, and total sleep deprivation. Each condition included two consecutive nights (the first always a night of uninterrupted sleep, and the second either a night of uninterrupted sleep, a night when sleep was reduced to 3 h, or a night of total sleep deprivation), as well as two days in which performance was assessed at 10 different time points (08:00, 08:30, 09:00, 09:30, 10:00, 11:00, 14:00, 17:00, 20:00, and 23:00 h). From 08:00 to 09:00 h, reaction times in the partial sleep-reduction and total sleep-deprivation conditions were at a similar level and were slower than those observed in the uninterrupted sleep condition. In the same time period, the frequency of lapses in the total sleep-deprivation condition was higher than in the partial sleep-reduction condition, while this latter condition never differed from the uninterrupted sleep condition. The results indicate that both sleep inertia and sleep-loss sleepiness lead to an increase in response latencies, but only extreme sleepiness leads to an increase in lapse frequency. We conclude that while reaction times slow as a result of both sleep inertia and sleep-loss sleepiness, lapses appear to be a specific feature of sleep-loss sleepiness.

  12. Time-lapse electrical surveys to locate infiltration zones in weathered hard rock tropical areas

    Science.gov (United States)

    Wubda, M.; Descloitres, M.; Yalo, N.; Ribolzi, O.; Vouillamoz, J. M.; Boukari, M.; Hector, B.; Séguis, L.

    2017-07-01

    In West Africa, infiltration and groundwater recharge processes in hard rock areas are depending on climatic, surface and subsurface conditions, and are poorly documented. Part of the reason is that identification, location and monitoring of these processes is still a challenge. Here, we explore the potential for time-lapse electrical surveys to bring additional information on these processes for two different climate situations: a semi-arid Sahelian site (north of Burkina and a humid Sudanian site (north of Benin), respectively focusing on indirect (localized) and direct (diffuse) recharge processes. The methodology is based on surveys in dry season and rainy season on typical pond or gully using Electrical Resistivity Tomography (ERT) and frequency electromagnetic (FEM) apparent conductivity mapping. The results show that in the Sahelian zone an indirect recharge occurs as expected, but infiltration doesn't takes place at the center of the pond to the aquifer, but occurs laterally in the banks. In Sudanian zone, the ERT survey shows a direct recharge process as expected, but also a complicated behavior of groundwater dilution, as well as the role of hardpans for fast infiltration. These processes are ascertained by groundwater monitoring in adjacent observing wells. At last, FEM time lapse mapping is found to be difficult to quantitatively interpreted due to the non-uniqueness of the model, clearly evidenced comparing FEM result to auger holes monitoring. Finally, we found that time-lapse ERT can be an efficient way to track infiltration processes across ponds and gullies in both climatic conditions, the Sahelian setting providing results easier to interpret, due to significant resistivity contrasts between dry and rain seasons. Both methods can be used for efficient implementation of punctual sensors for complementary studies. However, FEM time-lapse mapping remains difficult to practice without external information that renders this method less attractive for

  13. Probabilistic 3-D time-lapse inversion of magnetotelluric data: Application to an enhanced geothermal system

    Science.gov (United States)

    Rosas-Carbajal, Marina; Linde, Nicolas; Peacock, Jared R.; Zyserman, F. I.; Kalscheuer, Thomas; Thiel, Stephan

    2015-01-01

    Surface-based monitoring of mass transfer caused by injections and extractions in deep boreholes is crucial to maximize oil, gas and geothermal production. Inductive electromagnetic methods, such as magnetotellurics, are appealing for these applications due to their large penetration depths and sensitivity to changes in fluid conductivity and fracture connectivity. In this work, we propose a 3-D Markov chain Monte Carlo inversion of time-lapse magnetotelluric data to image mass transfer following a saline fluid injection. The inversion estimates the posterior probability density function of the resulting plume, and thereby quantifies model uncertainty. To decrease computation times, we base the parametrization on a reduced Legendre moment decomposition of the plume. A synthetic test shows that our methodology is effective when the electrical resistivity structure prior to the injection is well known. The centre of mass and spread of the plume are well retrieved.We then apply our inversion strategy to an injection experiment in an enhanced geothermal system at Paralana, South Australia, and compare it to a 3-D deterministic time-lapse inversion. The latter retrieves resistivity changes that are more shallow than the actual injection interval, whereas the probabilistic inversion retrieves plumes that are located at the correct depths and oriented in a preferential north-south direction. To explain the time-lapse data, the inversion requires unrealistically large resistivity changes with respect to the base model. We suggest that this is partly explained by unaccounted subsurface heterogeneities in the base model from which time-lapse changes are inferred.

  14. Seismic time-lapse imaging using Interferometric least-squares migration

    KAUST Repository

    Sinha, Mrinal

    2016-09-06

    One of the problems with 4D surveys is that the environmental conditions change over time so that the experiment is insufficiently repeatable. To mitigate this problem, we propose the use of interferometric least-squares migration (ILSM) to estimate the migration image for the baseline and monitor surveys. Here, a known reflector is used as the reference reflector for ILSM. Results with synthetic and field data show that ILSM can eliminate artifacts caused by non-repeatability in time-lapse surveys.

  15. Lapsed kapsapõldudel mehe eest väljas / Anne Oja

    Index Scriptorium Estoniae

    Oja, Anne, 1970-

    2006-01-01

    Kadarbiku talu peremees Ants Pak kasutab oma põldudel 8-12-aastaste laste tööd. Vt. samas: Vanemad tohivad lapsi tööle panna vaid oma tallu ja pereettevõttesse. Vt. samas Gert D Hankewitz interv. talu peremehe Ants Pakìga: Vanem ise sokutab lapse meile. Kommenteerivad Alar Tamm, Tarmo Kriis, Mailis Reps, Juhan Salum, Janno Järve, Aivo Tamm, Dmitri Jegorov ja Liivi Lents

  16. Unsupervised automated high throughput phenotyping of RNAi time-lapse movies.

    Science.gov (United States)

    Failmezger, Henrik; Fröhlich, Holger; Tresch, Achim

    2013-10-04

    Gene perturbation experiments in combination with fluorescence time-lapse cell imaging are a powerful tool in reverse genetics. High content applications require tools for the automated processing of the large amounts of data. These tools include in general several image processing steps, the extraction of morphological descriptors, and the grouping of cells into phenotype classes according to their descriptors. This phenotyping can be applied in a supervised or an unsupervised manner. Unsupervised methods are suitable for the discovery of formerly unknown phenotypes, which are expected to occur in high-throughput RNAi time-lapse screens. We developed an unsupervised phenotyping approach based on Hidden Markov Models (HMMs) with multivariate Gaussian emissions for the detection of knockdown-specific phenotypes in RNAi time-lapse movies. The automated detection of abnormal cell morphologies allows us to assign a phenotypic fingerprint to each gene knockdown. By applying our method to the Mitocheck database, we show that a phenotypic fingerprint is indicative of a gene's function. Our fully unsupervised HMM-based phenotyping is able to automatically identify cell morphologies that are specific for a certain knockdown. Beyond the identification of genes whose knockdown affects cell morphology, phenotypic fingerprints can be used to find modules of functionally related genes.

  17. Using time-lapse gravity for groundwater model calibration: An application to alluvial aquifer storage

    DEFF Research Database (Denmark)

    Christiansen, Lars; Binning, Philip John; Rosbjerg, Dan

    2011-01-01

    The estimation of hydrological model parameters by calibration to field data is a critical step in the modeling process. However, calibration often fails because of parameter correlation. Here it is shown that time-lapse gravity data can be combined with hydraulic head data in a coupled hydrogeop......The estimation of hydrological model parameters by calibration to field data is a critical step in the modeling process. However, calibration often fails because of parameter correlation. Here it is shown that time-lapse gravity data can be combined with hydraulic head data in a coupled...... shows that time-lapse gravity data are especially useful to constrain specific yield. Furthermore, we demonstrate that evapotranspiration, and riverbed conductance are better constrained by coupled inversion to gravity and head data than to head data alone. When estimating the four parameters...... simultaneously, the six correlation coefficients were reduced from unity when only head data were employed to significantly lower values when gravity and head data were combined. Our analysis reveals that the estimated parameter values are not very sensitive to the choice of weighting between head and gravity...

  18. Effect of oxygen concentration on human embryo development evaluated by time-lapse monitoring

    DEFF Research Database (Denmark)

    Ingerslev, Hans Jakob; Hindkjær, Johnny Juhl; Kirkegaard, Kirstine

    2012-01-01

    was to evaluate the influence of oxygen tension on human pre-implantation development using time-lapse monitoring. Materials and methods: Human embryos were cultured to the blastocyst stage in a time-lapse incubator (EmbryoScope™) in 20% O2 (group 1), 20% O2 for 24 hours followed by culture in 5% O2 (group 2......) or in 5% O2 (group 3). Eligible were patients with age 8 oocytes retrieved. Group 1 consisted of 120 IVF/ICSI embryos from 26 patients recruited to a study conducted to evaluate the safety of the time-lapse incubator by randomising 1:1 embryos from a patient to culture......-points for each cell division and blastocyst stages were registered until 120 hours after oocyte retrieval. Only 2PN embryos completing the first cleavage were evaluated. The groups were compared using one-way ANOVA or Kruskall-Wallis test. Estimates are reported as medians with 95% confidence intervals. Time...

  19. Do ethnicity and gender moderate the influence of posttraumatic stress disorder on time to smoking lapse?

    Science.gov (United States)

    Wilson, Sarah M; Dedert, Eric A; Dennis, Paul A; Dennis, Michelle F; Calhoun, Patrick S; Kirby, Angela C; Beckham, Jean C

    2014-07-01

    Following a smoking cessation attempt, smokers with posttraumatic stress disorder (PTSD) experience smoking relapse at a higher and faster rate. Black ethnicity and female gender are also associated with lower success rates following smoking cessation. No study to date has prospectively examined how ethnicity and gender may moderate the effect of PTSD on smoking relapse. It was hypothesized that female gender and Black ethnicity would significantly predict early lapse after quitting; further, it was predicted that ethnicity and gender would moderate the effect of PTSD on relapse rate. Smokers with PTSD (n=48) and without PTSD (n=56) completed ecological momentary assessment (EMA) the week after a quit date, and self-initiated EMA entries after smoking lapse. Smoking abstinence was biologically verified. The sample included Black (62%) and White (38%) participants, and was 50% female. Study hypotheses were tested with Cox proportional hazards regression modeling time to first smoking lapse. Study results confirmed the main hypothesis, with a significant PTSD × Ethnicity interaction emerging. The effect of PTSD on smoking relapse was significant for White participants but not for Black participants. No significant gender moderation was found. Taken together, study results support previous research, and suggest that the relationship between smoking and PTSD is stronger for White smokers than for minorities. This study has significant implications for research in smoking and mental disease, as well as for smoking cessation treatments for Black smokers. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. EEG predictors of covert vigilant attention

    Science.gov (United States)

    Martel, Adrien; Dähne, Sven; Blankertz, Benjamin

    2014-06-01

    Objective. The present study addressed the question whether neurophysiological signals exhibit characteristic modulations preceding a miss in a covert vigilant attention task which mimics a natural environment in which critical stimuli may appear in the periphery of the visual field. Approach. Subjective, behavioural and encephalographic (EEG) data of 12 participants performing a modified Mackworth Clock task were obtained and analysed offline. The stimulus consisted of a pointer performing regular ticks in a clockwise sequence across 42 dots arranged in a circle. Participants were requested to covertly attend to the pointer and press a response button as quickly as possible in the event of a jump, a rare and random event. Main results. Significant increases in response latencies and decreases in the detection rates were found as a function of time-on-task, a characteristic effect of sustained attention tasks known as the vigilance decrement. Subjective sleepiness showed a significant increase over the duration of the experiment. Increased activity in the α-frequency range (8-14 Hz) was observed emerging and gradually accumulating 10 s before a missed target. Additionally, a significant gradual attenuation of the P3 event-related component was found to antecede misses by 5 s. Significance. The results corroborate recent findings that behavioural errors are presaged by specific neurophysiological activity and demonstrate that lapses of attention can be predicted in a covert setting up to 10 s in advance reinforcing the prospective use of brain-computer interface (BCI) technology for the detection of waning vigilance in real-world scenarios. Combining these findings with real-time single-trial analysis from BCI may pave the way for cognitive states monitoring systems able to determine the current, and predict the near-future development of the brain's attentional processes.

  1. Inter-laboratory agreement on embryo classification and clinical decision: Conventional morphological assessment vs. time lapse.

    Directory of Open Access Journals (Sweden)

    Luis Martínez-Granados

    Full Text Available The aim of this study is to determine inter-laboratory variability on embryo assessment using time-lapse platform and conventional morphological assessment. This study compares the data obtained from a pilot study of external quality control (EQC of time lapse, performed in 2014, with the classical EQC of the Spanish Society for the Study of Reproductive Biology (ASEBIR performed in 2013 and 2014. In total, 24 laboratories (8 using EmbryoScope™, 15 using Primo Vision™ and one with both platforms took part in the pilot study. The clinics that used EmbryoScope™ analysed 31 embryos and those using Primo Vision™ analysed 35. The classical EQC was implemented by 39 clinics, based on an analysis of 25 embryos per year. Both groups were required to evaluate various qualitative morphological variables (cell fragmentation, the presence of vacuoles, blastomere asymmetry and multinucleation, to classify the embryos in accordance with ASEBIR criteria and to stipulate the clinical decision taken. In the EQC time-lapse pilot study, the groups were asked to determine, as well as the above characteristics, the embryo development times, the number, opposition and size of pronuclei, the direct division of 1 into 3 cells and/or of 3 into 5 cells and false divisions. The degree of agreement was determined by calculating the intra-class correlation coefficients and the coefficient of variation for the quantitative variables and the Gwet index for the qualitative variables. For both EmbryoScope™ and Primo Vision™, two periods of greater inter-laboratory variability were observed in the times of embryo development events. One peak of variability was recorded among the laboratories addressing the first embryo events (extrusion of the second polar body and the appearance of pronuclei; the second peak took place between the times corresponding to the 8-cell and morula stages. In most of the qualitative variables analysed regarding embryo development, there

  2. Rock Slope Monitoring from 4D Time-Lapse Structure from Motion Analysis

    Science.gov (United States)

    Kromer, Ryan; Abellan, Antonio; Chyz, Alex; Hutchinson, Jean

    2017-04-01

    Structure from Motion (SfM) photogrammetry has become an important tool for studying earth surface processes because of its flexibility, ease of use, low cost and its capability of producing high quality 3-D surface models. A major benefit of SfM is that model accuracy is fit for purpose and surveys can be designed to meet a large range of spatial and temporal scales. In the Earth sciences, research in time-lapse SfM photogrammetry or videogrammetry is an area that is difficult to undertake due to complexities in acquiring, processing and managing large 4D datasets and represents an area with significant advancement potential (Eltner et al. 2016). In this study, we investigate the potential of 4D time-lapse SfM to monitor unstable rock slopes. We tested an array of statically mounted cameras collecting time-lapse photos of a limestone rock slope located along a highway in Canada. Our setup consisted of 8 DSLR cameras with 50 mm prime lenses spaced 2-3 m apart at a distance of 10 m from the slope. The portion of the rock slope monitored was 20 m wide and 6 m high. We collected data in four phases, each having 50 photographs taken simultaneously by each camera. The first phase of photographs was taken of the stable slope. In each successive phase, we gradually moved small, discrete blocks within the rock slope by 5-15 mm, simulating pre-failure deformation of rockfall. During the last phase we also removed discrete rock blocks, simulating rockfall. We used Agisoft Photoscan's 4D processing functionality and timeline tools to create 3D point clouds from the time-lapse photographs. These tools have the benefit of attaining better accuracy photo alignments as a greater number of photos are used. For change detection, we used the 4D filtering and calibration technique proposed by Kromer et al. (2015), which takes advantage of high degrees of spatial and temporal point redundancy to decrease measurement uncertainty. Preliminary results show that it is possible to attain

  3. Attention Mosaics: Studies of Organizational Attention

    OpenAIRE

    Carvalho de Mesquita Ferreira, Luciana

    2010-01-01

    textabstractOrganizational studies emphasizing the role of attention in organizational behavior depart from the idea that organizations, like individuals, have limited capacity to attend to environmental stimuli. The bounded capacity of the organizations to respond to stimuli is conditioned by the limited cognitions of individuals and by the limited capability of organizations to distribute, coordinate and integrate those cognitions. The cross-level nature of organizational attention, its dua...

  4. A state-space Bayesian framework for estimating biogeochemical transformations using time-lapse geophysical data

    Energy Technology Data Exchange (ETDEWEB)

    Chen, J.; Hubbard, S.; Williams, K.; Pride, S.; Li, L.; Steefel, C.; Slater, L.

    2009-04-15

    We develop a state-space Bayesian framework to combine time-lapse geophysical data with other types of information for quantitative estimation of biogeochemical parameters during bioremediation. We consider characteristics of end-products of biogeochemical transformations as state vectors, which evolve under constraints of local environments through evolution equations, and consider time-lapse geophysical data as available observations, which could be linked to the state vectors through petrophysical models. We estimate the state vectors and their associated unknown parameters over time using Markov chain Monte Carlo sampling methods. To demonstrate the use of the state-space approach, we apply it to complex resistivity data collected during laboratory column biostimulation experiments that were poised to precipitate iron and zinc sulfides during sulfate reduction. We develop a petrophysical model based on sphere-shaped cells to link the sulfide precipitate properties to the time-lapse geophysical attributes and estimate volume fraction of the sulfide precipitates, fraction of the dispersed, sulfide-encrusted cells, mean radius of the aggregated clusters, and permeability over the course of the experiments. Results of the case study suggest that the developed state-space approach permits the use of geophysical datasets for providing quantitative estimates of end-product characteristics and hydrological feedbacks associated with biogeochemical transformations. Although tested here on laboratory column experiment datasets, the developed framework provides the foundation needed for quantitative field-scale estimation of biogeochemical parameters over space and time using direct, but often sparse wellbore data with indirect, but more spatially extensive geophysical datasets.

  5. Feeling the Heat: Supraglacial Lake Changes as Observed via Time-Lapse Photography, Ngozumpa Glacier, Nepal

    Science.gov (United States)

    Horodyskyj, U. N.; Breashears, D.; Bilham, R. G.

    2011-12-01

    Supraglacial lakes are suspected of playing a catalytic role in the current rapid melting rate of temperate glaciers. Our field work on the Ngozumpa glacier, in the Nepalese Himalaya, was targeted to quantify the physics of this process. A field season was conducted in June 2011 to investigate the formation and evolution of these lakes via time-lapse photography. One supraglacial lake in particular was chosen for more intensive study. A pressure transducer recorded lake level changes throughout the field season; probes measured surface water temperature, water temperature at depth, and air temperature; and solar irradiation (incoming and outgoing) was measured with a pair of silicon pyranometers. Depth surveys were conducted, water samples were collected, and melt rates on north and south facing ice walls also were measured with a laser rangefinder during hours of peak insolation. During the course of the field season, 28 cm of overall water rise was measured in the lake. Two major icefall events a week apart contributed to 8 and 6 cm, respectively, rise alone. Surface water and air temperatures increased during this time, along with the amount of solar irradiation reaching the surface of the lake. South-facing ice walls were found to melt faster, but no walls were found to be immune to melt and collapse. Hourly time-lapse photography captured a major icefall in this lake, while another camera captured a larger lake farther upglacier draining more than 3 meters overnight. A third camera, aimed near the terminus, captured a lake changing in color (from milky blue to brown) and doubling in size during the field season. These initial results show substantial change in a short amount of time. Continued time-lapse photography should provide us with an even better record of surface evolution on this climatically sensitive glacier in the Himalaya.

  6. Monitoring hydraulic processes with automated time-lapse electrical resistivity tomography (ALERT)

    Science.gov (United States)

    Kuras, Olivier; Pritchard, Jonathan D.; Meldrum, Philip I.; Chambers, Jonathan E.; Wilkinson, Paul B.; Ogilvy, Richard D.; Wealthall, Gary P.

    2009-10-01

    Hydraulic processes in porous media can be monitored in a minimally invasive fashion by time-lapse electrical resistivity tomography (ERT). The permanent installation of specifically designed ERT instrumentation, telemetry and information technology (IT) infrastructure enables automation of data collection, transfer, processing, management and interpretation. Such an approach gives rise to a dramatic increase in temporal resolution, thus providing new insight into rapidly occurring subsurface processes. In this paper, we discuss a practical implementation of automated time-lapse ERT. We present the results of a recent study in which we used controlled hydraulic experiments in two test cells at reduced field scale to explore the limiting conditions for process monitoring with cross-borehole ERT measurements. The first experiment used three adjacent boreholes to monitor rapidly rising and falling water levels. For the second experiment, we injected a saline tracer into a homogeneous flow field in freshwater-saturated sand; the dynamics of the plume were then monitored with 2D measurements across a 9-borehole fence and 3D measurements across a 3 × 3 grid of boreholes. We investigated different strategies for practical data acquisition and show that simple re-ordering of ERT measurement schemes can help harmonise data collection with the nature of the monitored process. The methodology of automated time-lapse ERT was found to perform well in different monitoring scenarios (2D/3D plus time) at time scales associated with realistic subsurface processes. The limiting factor is the finite amount of time needed for the acquisition of sufficiently comprehensive datasets. We found that, given the complexity of our monitoring scenarios, typical frame rates of at least 1.5-3 images per hour were possible without compromising image quality.

  7. Fast and robust optical flow for time-lapse microscopy using super-voxels.

    Science.gov (United States)

    Amat, Fernando; Myers, Eugene W; Keller, Philipp J

    2013-02-01

    Optical flow is a key method used for quantitative motion estimation of biological structures in light microscopy. It has also been used as a key module in segmentation and tracking systems and is considered a mature technology in the field of computer vision. However, most of the research focused on 2D natural images, which are small in size and rich in edges and texture information. In contrast, 3D time-lapse recordings of biological specimens comprise up to several terabytes of image data and often exhibit complex object dynamics as well as blurring due to the point-spread-function of the microscope. Thus, new approaches to optical flow are required to improve performance for such data. We solve optical flow in large 3D time-lapse microscopy datasets by defining a Markov random field (MRF) over super-voxels in the foreground and applying motion smoothness constraints between super-voxels instead of voxel-wise. This model is tailored to the specific characteristics of light microscopy datasets: super-voxels help registration in textureless areas, the MRF over super-voxels efficiently propagates motion information between neighboring cells and the background subtraction and super-voxels reduce the dimensionality of the problem by an order of magnitude. We validate our approach on large 3D time-lapse datasets of Drosophila and zebrafish development by analyzing cell motion patterns. We show that our approach is, on average, 10 × faster than commonly used optical flow implementations in the Insight Tool-Kit (ITK) and reduces the average flow end point error by 50% in regions with complex dynamic processes, such as cell divisions. Source code freely available in the Software section at http://janelia.org/lab/keller-lab.

  8. Exploring the Resolution of Time-Lapse Microgravity at an Aquifer Storage and Recovery Site

    Science.gov (United States)

    Bradley, C. C.; Ali, M.; Levannier, A.

    2008-12-01

    Time-Lapse Microgravity can reveal relatively small underground fluid displacements via the redistribution of density-contrast at fluid boundaries. The method has, for example, been successfully demonstrated in underground natural gas storage and carbon sequestration studies, and has clear potential for hydrological research and applications such as mining and hydrocarbon reservoir management. For surveys based on modern spring-type gravimeters, the technique's basic measurement resolution is limited by instrument drift, offset errors, and viscoelastic strain hysteresis of the sensor. Despite the sophistication of modern instruments, actual field performance of gravimeters still depends on operator technique and survey conditions. To explore the ultimate resolution of field microgravity (and time-lapse measurements, in particular), we have made repeated gravity surveys of a shallow aquifer storage and recovery test site in the UAE, where injection produces a 'water mound' - localized vertical water-level shifts - monitored by a set of instrumented wells. Based on field measurements and additional laboratory testing of our Scintrex CG-5 gravimeter, we find that the main limit on measurement resolution is from orientation strain hysteresis - a variable amplitude error that decays in approximately 30 minutes, typically in response to orientation during transport between measurement stations. Still, carefully conducted surveys (during the summer, in the desert conditions of the UAE) demonstrate time-lapse microgravity resolution of about 3 microGals, corresponding to a water-level shift of about 0.3 m for this aquifer. In this paper, we will discuss what a 'careful survey' requires and present our detailed testing and survey results.

  9. Time-lapse 3D imaging of calcite precipitation in a microporous column

    Science.gov (United States)

    Godinho, Jose R. A.; Withers, Philip J.

    2018-02-01

    Time-lapse X-ray computed tomography is used to image the evolution of calcite precipitation during flow through microporous quartz over the course of 400 h. The growth rate decreases by more than seven times, which is linked to the clogging of flow paths that restricts flow to some regions of the column. Fewer precipitates are observed as a function of column depth, which is found to be related to a differential nucleation density along the sample. A higher nucleation density closer to the inlet implies more crystal volume increase per unit of time without affecting the rate if normalized to the surface area of crystals. Our overall growth rates measured in porous media are orders of magnitude slower than growth rates derived from traditional precipitation experiments on free surfaces. Based on our time-lapse results we hypothesize a scenario where the evolving distribution of precipitates within a pore structure during precipitation progressively modifies the local transport through the pores. Within less permeable regions the saturation index may be lower than along the main flow paths. Therefore, the reactive crystal surfaces within those regions grow at a slower rate than that expected from the bulk fluid composition. Since the amount of reactive surface area within these less permeable regions increases over time, the overall growth rate decreases without a necessary significant change of the bulk fluid composition along more permeable flow paths. In conclusion, the overall growth rates in an evolving porous media expected from bulk fluid compositions alone can be overestimated due to the development of stagnant sub-regions where the reactive surface area is bath by a solution with lower saturation index. In this context we highlight the value of time-lapse 3D studies for understanding the dynamics of mineral precipitation in porous media.

  10. Time-lapse electrical geophysical monitoring of amendment-based biostimulation

    Science.gov (United States)

    Johnson, Timothy C.; Versteeg, Roelof J.; Day-Lewis, Frederick D.; Major, William; Lane, John W.

    2015-01-01

    Biostimulation is increasingly used to accelerate microbial remediation of recalcitrant groundwater contaminants. Effective application of biostimulation requires successful emplacement of amendment in the contaminant target zone. Verification of remediation performance requires postemplacement assessment and contaminant monitoring. Sampling-based approaches are expensive and provide low-density spatial and temporal information. Time-lapse electrical resistivity tomography (ERT) is an effective geophysical method for determining temporal changes in subsurface electrical conductivity. Because remedial amendments and biostimulation-related biogeochemical processes often change subsurface electrical conductivity, ERT can complement and enhance sampling-based approaches for assessing emplacement and monitoring biostimulation-based remediation.Field studies demonstrating the ability of time-lapse ERT to monitor amendment emplacement and behavior were performed during a biostimulation remediation effort conducted at the Department of Defense Reutilization and Marketing Office (DRMO) Yard, in Brandywine, Maryland, United States. Geochemical fluid sampling was used to calibrate a petrophysical relation in order to predict groundwater indicators of amendment distribution. The petrophysical relations were field validated by comparing predictions to sequestered fluid sample results, thus demonstrating the potential of electrical geophysics for quantitative assessment of amendment-related geochemical properties. Crosshole radar zero-offset profile and borehole geophysical logging were also performed to augment the data set and validate interpretation.In addition to delineating amendment transport in the first 10 months after emplacement, the time-lapse ERT results show later changes in bulk electrical properties interpreted as mineral precipitation. Results support the use of more cost-effective surface-based ERT in conjunction with limited field sampling to improve spatial

  11. Time-lapse refraction seismic tomography for the detection of ground ice degradation

    Directory of Open Access Journals (Sweden)

    C. Hilbich

    2010-07-01

    Full Text Available The ice content of the subsurface is a major factor controlling the natural hazard potential of permafrost degradation in alpine terrain. Monitoring of changes in ice content is therefore similarly important as temperature monitoring in mountain permafrost. Although electrical resistivity tomography monitoring (ERTM proved to be a valuable tool for the observation of ice degradation, results are often ambiguous or contaminated by inversion artefacts. In theory, the sensitivity of P-wave velocity of seismic waves to phase changes between unfrozen water and ice is similar to the sensitivity of electric resistivity. Provided that the general conditions (lithology, stratigraphy, state of weathering, pore space remain unchanged over the observation period, temporal changes in the observed travel times of repeated seismic measurements should indicate changes in the ice and water content within the pores and fractures of the subsurface material. In this paper, a time-lapse refraction seismic tomography (TLST approach is applied as an independent method to ERTM at two test sites in the Swiss Alps. The approach was tested and validated based on a the comparison of time-lapse seismograms and analysis of reproducibility of the seismic signal, b the analysis of time-lapse travel time curves with respect to shifts in travel times and changes in P-wave velocities, and c the comparison of inverted tomograms including the quantification of velocity changes. Results show a high potential of the TLST approach concerning the detection of altered subsurface conditions caused by freezing and thawing processes. For velocity changes on the order of 3000 m/s even an unambiguous identification of significant ice loss is possible.

  12. 3D Time-lapse Imaging and Quantification of Mitochondrial Dynamics

    Science.gov (United States)

    Sison, Miguel; Chakrabortty, Sabyasachi; Extermann, Jérôme; Nahas, Amir; James Marchand, Paul; Lopez, Antonio; Weil, Tanja; Lasser, Theo

    2017-02-01

    We present a 3D time-lapse imaging method for monitoring mitochondrial dynamics in living HeLa cells based on photothermal optical coherence microscopy and using novel surface functionalization of gold nanoparticles. The biocompatible protein-based biopolymer coating contains multiple functional groups which impart better cellular uptake and mitochondria targeting efficiency. The high stability of the gold nanoparticles allows continuous imaging over an extended time up to 3000 seconds without significant cell damage. By combining temporal autocorrelation analysis with a classical diffusion model, we quantify mitochondrial dynamics and cast these results into 3D maps showing the heterogeneity of diffusion parameters across the whole cell volume.

  13. Calibrating vadose zone models with time-lapse gravity data: a forced infiltration experiment

    DEFF Research Database (Denmark)

    Christiansen, Lars; Hansen, Allan Bo; Zibar, Majken Caroline Looms

    A change in soil water content is a change in mass stored in the subsurface, and when large enough, can be measured with a gravity meter. Over the last few decades there has been increased use of ground-based time-lapse gravity measurements to infer hydrogeological parameters. These studies have...... in the unsaturated zone. These results are confirmed by field measurements of gravity and georadar data at a forced infiltration experiment conducted over 14 days on a grassland area of 10 m by 10 m. An unsaturated zone infiltration model can be calibrated using the gravity data with good agreement to the field data...

  14. A software solution for recording circadian oscillator features in time-lapse live cell microscopy

    Directory of Open Access Journals (Sweden)

    Salmon Patrick

    2010-07-01

    Full Text Available Abstract Background Fluorescent and bioluminescent time-lapse microscopy approaches have been successfully used to investigate molecular mechanisms underlying the mammalian circadian oscillator at the single cell level. However, most of the available software and common methods based on intensity-threshold segmentation and frame-to-frame tracking are not applicable in these experiments. This is due to cell movement and dramatic changes in the fluorescent/bioluminescent reporter protein during the circadian cycle, with the lowest expression level very close to the background intensity. At present, the standard approach to analyze data sets obtained from time lapse microscopy is either manual tracking or application of generic image-processing software/dedicated tracking software. To our knowledge, these existing software solutions for manual and automatic tracking have strong limitations in tracking individual cells if their plane shifts. Results In an attempt to improve existing methodology of time-lapse tracking of a large number of moving cells, we have developed a semi-automatic software package. It extracts the trajectory of the cells by tracking theirs displacements, makes the delineation of cell nucleus or whole cell, and finally yields measurements of various features, like reporter protein expression level or cell displacement. As an example, we present here single cell circadian pattern and motility analysis of NIH3T3 mouse fibroblasts expressing a fluorescent circadian reporter protein. Using Circadian Gene Express plugin, we performed fast and nonbiased analysis of large fluorescent time lapse microscopy datasets. Conclusions Our software solution, Circadian Gene Express (CGE, is easy to use and allows precise and semi-automatic tracking of moving cells over longer period of time. In spite of significant circadian variations in protein expression with extremely low expression levels at the valley phase, CGE allows accurate and

  15. Live-streaming: Time-lapse video evidence of novel streamer formation mechanism and varying viscosity.

    Science.gov (United States)

    Parvinzadeh Gashti, Mazeyar; Bellavance, Julien; Kroukamp, Otini; Wolfaardt, Gideon; Taghavi, Seyed Mohammad; Greener, Jesse

    2015-07-01

    Time-lapse videos of growing biofilms were analyzed using a background subtraction method, which removed camouflaging effects from the heterogeneous field of view to reveal evidence of streamer formation from optically dense biofilm segments. In addition, quantitative measurements of biofilm velocity and optical density, combined with mathematical modeling, demonstrated that streamer formation occurred from mature, high-viscosity biofilms. We propose a streamer formation mechanism by sudden partial detachment, as opposed to continuous elongation as observed in other microfluidic studies. Additionally, streamer formation occurred in straight microchannels, as opposed to serpentine or pseudo-porous channels, as previously reported.

  16. Soil Contamination, Advanced integrated characterisation and time-lapse Monitoring, SoilCAM project highlights

    Science.gov (United States)

    French, H. K.; Van Der Zee, S. E.; Wehrer, M.; Godio, A.; Pedersen, L. B.; Tsocano, G.

    2013-12-01

    The SoilCAM project (2008- 2012, EU-FP7-212663) aimed at improving methods for monitoring subsurace contaminant distribution and biodegradation. Two test sites were chosen, Oslo airport Gardermoen, Norway where de-icing agents infiltrate the soil during snowmelt and the Trecate site in Italy where an inland crude oil spill occurred in 1994. A number of geophysical investigation techniques were combined with soil and water sampling techniques. Data obtained from time-lapse measurements were further analysed by numerical modelling of flow and transport at different scales in order to characterise transport processes in the unsaturated and saturated zones. Laboratory experiments provided physical and biogeochemical data for model parameterisation and to select remediation methods. The geophysical techniques were used to map geological heterogeneities and to conduct time-lapse measurements of processes in the unsaturated zone. Both cross borehole and surface electrodes were used for electrical resistivity and induced polarisation surveys. Results showed clear indications of areas highly affected by de-icing chemicals along the runway at Oslo airport. The time lapse measurements along the runway at the airport showed infiltration patterns during snowmelt and were used to validate 2D unsaturated flow and transport simulations using SUTRA. The simulations illustrate the effect of layering geological structures and membranes, buried parallel to the runway, on the flow pattern. Complex interaction between bio-geo-chemical processes in a 1D vertical profile along the runway were described with the ORCHESTRA model. Smaller scale field site measurements revealed increase of iron and manganese during degradation of de-icing chemicals. At the Trecate site a combination of georadar, electrical resistivity and radio magneto telluric provided a broad outline of the geology down to 50 m. Anomalies in the Induced polarisation and electrical resistivity data from the cross borehole

  17. Reconstructed imaging of acoustic cloak using time-lapse reversal method

    Science.gov (United States)

    Zhou, Chen; Cheng, Ying; Xu, Jian-yi; Li, Bo; Liu, Xiao-jun

    2014-08-01

    We proposed and investigated a solution to the inverse acoustic cloak problem, an anti-stealth technology to make cloaks visible, using the time-lapse reversal (TLR) method. The TLR method reconstructs the image of an unknown acoustic cloak by utilizing scattered acoustic waves. Compared to previous anti-stealth methods, the TLR method can determine not only the existence of a cloak but also its exact geometric information like definite shape, size, and position. Here, we present the process for TLR reconstruction based on time reversal invariance. This technology may have potential applications in detecting various types of cloaks with different geometric parameters.

  18. Mechanisms of Perceptual Attention

    National Research Council Canada - National Science Library

    Dosher, Barbara

    2000-01-01

    .... Attention may affect the perceived clarity of visual displays and improve performance. In this project, a powerful external noise method was developed to identify and characterize the effect of attention on perceptual performance in visual tasks...

  19. Mechanism of Perceptual Attention

    National Research Council Canada - National Science Library

    Lu, Zhong-Lin

    2000-01-01

    .... Attention may affect the perceived clarity of visual displays and improve performance. In this project, a powerful external noise method was developed to identify and characterize the effect of attention on perceptual performance in visual tasks...

  20. Attention processes in autism

    National Research Council Canada - National Science Library

    Martos-Pérez, J

    2008-01-01

    ... findings that have been obtained so far are also reported. Some attentional processes, such as selective or sustained attention, are not altered in autism or not enough evidence has been found to support such a hypothesis...

  1. Attention Competition with Advertisement

    OpenAIRE

    Cetin, Uzay; Bingol, Haluk O.

    2012-01-01

    In the new digital age, information is available in large quantities. Since information consumes primarily the attention of its recipients, the scarcity of attention is becoming the main limiting factor. In this study, we investigate the impact of advertisement pressure on a cultural market where consumers have a limited attention capacity. A model of competition for attention is developed and investigated analytically and by simulation. Advertisement is found to be much more effective when a...

  2. Attention competition with advertisement.

    Science.gov (United States)

    Cetin, Uzay; Bingol, Haluk O

    2014-09-01

    In the new digital age, information is available in large quantities. Since information consumes primarily the attention of its recipients, the scarcity of attention is becoming the main limiting factor. In this study, we investigate the impact of advertisement pressure on a cultural market where consumers have a limited attention capacity. A model of competition for attention is developed and investigated analytically and by simulation. Advertisement is found to be much more effective when the attention capacity of agents is extremely scarce. We have observed that the market share of the advertised item improves if dummy items are introduced to the market while the strength of the advertisement is kept constant.

  3. Attention competition with advertisement

    Science.gov (United States)

    Cetin, Uzay; Bingol, Haluk O.

    2014-09-01

    In the new digital age, information is available in large quantities. Since information consumes primarily the attention of its recipients, the scarcity of attention is becoming the main limiting factor. In this study, we investigate the impact of advertisement pressure on a cultural market where consumers have a limited attention capacity. A model of competition for attention is developed and investigated analytically and by simulation. Advertisement is found to be much more effective when the attention capacity of agents is extremely scarce. We have observed that the market share of the advertised item improves if dummy items are introduced to the market while the strength of the advertisement is kept constant.

  4. Principles of visual attention

    DEFF Research Database (Denmark)

    Bundesen, Claus; Habekost, Thomas

    The nature of attention is one of the oldest and most central problems in psychology. A huge amount of research has been produced on this subject in the last half century, especially on attention in the visual modality, but a general explanation has remained elusive. Many still view attention...... research as a field that is fundamentally fragmented. This book takes a different perspective and presents a unified theory of visual attention: the TVA model. The TVA model explains the many aspects of visual attention by just two mechanisms for selection of information: filtering and pigeonholing....... These mechanisms are described in a set of simple equations, which allow TVA to mathematically model a large number of classical results in the attention literature. The theory explains psychological and neuroscientific findings by the same equations; TVA is a complete theory of visual attention, linking mind...

  5. Intelligent data analysis to model and understand live cell time-lapse sequences.

    Science.gov (United States)

    Paterson, Allan; Ashtari, M; Ribé, D; Stenbeck, G; Tucker, A

    2012-01-01

    One important aspect of cellular function, which is at the basis of tissue homeostasis, is the delivery of proteins to their correct destinations. Significant advances in live cell microscopy have allowed tracking of these pathways by following the dynamics of fluorescently labelled proteins in living cells. This paper explores intelligent data analysis techniques to model the dynamic behavior of proteins in living cells as well as to classify different experimental conditions. We use a combination of decision tree classification and hidden Markov models. In particular, we introduce a novel approach to "align" hidden Markov models so that hidden states from different models can be cross-compared. Our models capture the dynamics of two experimental conditions accurately with a stable hidden state for control data and multiple (less stable) states for the experimental data recapitulating the behaviour of particle trajectories within live cell time-lapse data. In addition to having successfully developed an automated framework for the classification of protein transport dynamics from live cell time-lapse data our model allows us to understand the dynamics of a complex trafficking pathway in living cells in culture.

  6. The critical time-lapse between various restoration placements and subsequent endodontic intervention.

    Science.gov (United States)

    Kwang, Sarah; Aminoshariae, Anita; Harding, Jarrod; Montagnese, Thomas A; Mickel, Andre

    2014-12-01

    The purpose of this study was 2-fold: (1) to investigate the critical time-lapse of endodontic intervention subsequent to various restorations and tooth surfaces and (2) to assess and compare the risk factors associated with the restorations, tooth surfaces, and endodontic treatment. A comprehensive computerized analysis of all dental school patients at the Case Western Reserve University School of Dental Medicine who received restorations from 2008-2013 was obtained. Inclusion and exclusion criteria were applied. The sample size was limited to teeth with endodontic treatment completed by the endodontic postgraduate dental clinic. Data collected included restoration type, restored tooth surfaces, tooth type, and the dates of restoration and subsequent endodontic treatment. A 2-sample paired t test (95% confidence interval, P endodontic intervention was 270 days, with a mean difference of 247-294 days (P endodontic intervention. Teeth with 2 or more restorative surfaces required endodontic intervention (P endodontic treatment after restoration placement, the critical time-lapse was 9 months. Composite restorations and teeth with 2 or more restorative surfaces were significantly associated with endodontic treatment. From the results of the current study, we recommended that all dental practitioners should perform a thorough endodontic evaluation and diagnosis before, during, and after all restorative procedures. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  7. A study on quality-adjusted impact of time lapse on iris recognition

    Science.gov (United States)

    Sazonova, Nadezhda; Hua, Fang; Liu, Xuan; Remus, Jeremiah; Ross, Arun; Hornak, Lawrence; Schuckers, Stephanie

    2012-06-01

    Although human iris pattern is widely accepted as a stable biometric feature, recent research has found some evidences on the aging effect of iris system. In order to investigate changes in iris recognition performance due to the elapsed time between probe and gallery iris images, we examine the effect of elapsed time on iris recognition utilizing 7,628 iris images from 46 subjects with an average of ten visits acquired over two years from a legacy database at Clarkson University. Taken into consideration the impact of quality factors such as local contrast, illumination, blur and noise on iris recognition performance, regression models are built with and without quality metrics to evaluate the degradation of iris recognition performance based on time lapse factors. Our experimental results demonstrate the decrease of iris recognition performance along with increased elapsed time based on two iris recognition system (the modified Masek algorithm and a commercial software VeriEye SDK). These results also reveal the significance of quality factors in iris recognition regression indicating the variability in match scores. According to the regression analysis, our study in this paper helps provide the quantified decrease on match scores with increased elapsed time, which indicates the possibility to implement the prediction scheme for iris recognition performance based on learning of impact on time lapse factors.

  8. Noise-free accurate count of microbial colonies by time-lapse shadow image analysis.

    Science.gov (United States)

    Ogawa, Hiroyuki; Nasu, Senshi; Takeshige, Motomu; Funabashi, Hisakage; Saito, Mikako; Matsuoka, Hideaki

    2012-12-01

    Microbial colonies in food matrices could be counted accurately by a novel noise-free method based on time-lapse shadow image analysis. An agar plate containing many clusters of microbial colonies and/or meat fragments was trans-illuminated to project their 2-dimensional (2D) shadow images on a color CCD camera. The 2D shadow images of every cluster distributed within a 3-mm thick agar layer were captured in focus simultaneously by means of a multiple focusing system, and were then converted to 3-dimensional (3D) shadow images. By time-lapse analysis of the 3D shadow images, it was determined whether each cluster comprised single or multiple colonies or a meat fragment. The analytical precision was high enough to be able to distinguish a microbial colony from a meat fragment, to recognize an oval image as two colonies contacting each other, and to detect microbial colonies hidden under a food fragment. The detection of hidden colonies is its outstanding performance in comparison with other systems. The present system attained accuracy for counting fewer than 5 colonies and is therefore of practical importance. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. The Extreme Ice Survey: Capturing and Conveying Glacial Processes Through Time-Lapse Imagery and Narration

    Science.gov (United States)

    Balog, J. D.; Box, J. E.; Pfeffer, W. T.; Hood, E. W.; Fagre, D. B.; Anker, C.; O'Neel, S.

    2010-12-01

    The Extreme Ice Survey (EIS) uses time-lapse photography, conventional photography, and video to document rapid change in the Earth's glacial ice. The EIS team currently has 38 time-lapse cameras at sites in Greenland, Iceland, Alaska, the Rocky Mountains and Nepal. EIS supplements this ongoing record with annual repeat photography in British Columbia, Iceland, the Alps, and Bolivia. EIS imagery supplies basic knowledge in glacier dynamics to the science community, as well as compelling, engaging narratives to the general public about the immediacy of the Anthropocene and climate change. Visual materials from EIS have impacted more than 150 million people, ranging from White House staff, the U. S. Congress and government agency officials to globally influential corporate officers and all age strata of the general public. Media products include a National Geographic/NOVA special, two National Geographic magazine articles, a feature in Parade magazine (circulation 71 million), and numerous presentations on CNN, NBC, BBC and National Public Radio. Columbia Glacier, Alaska, June 2006, May 2007, June 2008 terminus indicated.

  10. Time lapse seismic observations and effects of reservoir compressibility at Teal South oil field

    Science.gov (United States)

    Islam, Nayyer

    One of the original ocean-bottom time-lapse seismic studies was performed at the Teal South oil field in the Gulf of Mexico during the late 1990's. This work reexamines some aspects of previous work using modern analysis techniques to provide improved quantitative interpretations. Using three-dimensional volume visualization of legacy data and the two phases of post-production time-lapse data, I provide additional insight into the fluid migration pathways and the pressure communication between different reservoirs, separated by faults. This work supports a conclusion from previous studies that production from one reservoir caused regional pressure decline that in turn resulted in liberation of gas from multiple surrounding unproduced reservoirs. I also provide an explanation for unusual time-lapse changes in amplitude-versus-offset (AVO) data related to the compaction of the producing reservoir which, in turn, changed an isotropic medium to an anisotropic medium. In the first part of this work, I examine regional changes in seismic response due to the production of oil and gas from one reservoir. The previous studies primarily used two post-production ocean-bottom surveys (Phase I and Phase II), and not the legacy streamer data, due to the unavailability of legacy prestack data and very different acquisition parameters. In order to incorporate the legacy data in the present study, all three post-stack data sets were cross-equalized and examined using instantaneous amplitude and energy volumes. This approach appears quite effective and helps to suppress changes unrelated to production while emphasizing those large-amplitude changes that are related to production in this noisy (by current standards) suite of data. I examine the multiple data sets first by using the instantaneous amplitude and energy attributes, and then also examine specific apparent time-lapse changes through direct comparisons of seismic traces. In so doing, I identify time-delays that, when

  11. Possible mechanism of polyspermy block in human oocytes observed by time-lapse cinematography.

    Science.gov (United States)

    Mio, Yasuyuki; Iwata, Kyoko; Yumoto, Keitaro; Kai, Yoshiteru; Sargant, Haruka C; Mizoguchi, Chizuru; Ueda, Minako; Tsuchie, Yuka; Imajo, Akifumi; Iba, Yumiko; Nishikori, Kyoko

    2012-09-01

    To analyze the fertilization process related to polyspermy block in human oocytes using an in vitro culturing system for time-lapse cinematography. We had 122 oocytes donated for this study from couples that provided informed consent. We recorded human oocytes at 2,000 to 2,800 frames every 10 s during the fertilization process and thereafter every 2 min using a new in vitro culture system originally developed by the authors for time-lapse cinematography. We displayed 30 frames per second for analysis of the polyspermy block during fertilization. Three oocytes showed the leading and following sperm within the zona pellucida in the same microscopic field. The dynamic images obtained during the fertilization process using this new system revealed that once a leading sperm penetrated the zona pellucida and attached to the oocyte membrane, a following sperm was arrested from further penetration into the zona pellucida within 10 s. The present results strongly suggest the existence of a novel mechanism of polyspermy block that takes place at the zona pellucida immediately after fertilization. These findings are clearly different from previous mechanisms describing polyspermy block as the oocyte membrane block to sperm penetration and the zona reaction. The finding presented herein thus represents a novel discovery about the highly complicated polyspermy block mechanism occurring in human oocytes.

  12. Estimation and discrimination of stochastic biochemical circuits from time-lapse microscopy data.

    Directory of Open Access Journals (Sweden)

    David Thorsley

    Full Text Available The ability of systems and synthetic biologists to observe the dynamics of cellular behavior is hampered by the limitations of the sensors, such as fluorescent proteins, available for use in time-lapse microscopy. In this paper, we propose a generalized solution to the problem of estimating the state of a stochastic chemical reaction network from limited sensor information generated by microscopy. We mathematically derive an observer structure for cells growing under time-lapse microscopy and incorporates the effects of cell division in order to estimate the dynamically-changing state of each cell in the colony. Furthermore, the observer can be used to discrimate between models by treating model indices as states whose values do not change with time. We derive necessary and sufficient conditions that specify when stochastic chemical reaction network models, interpreted as continuous-time Markov chains, can be distinguished from each other under both continual and periodic observation. We validate the performance of the observer on the Thattai-van Oudenaarden model of transcription and translation. The observer structure is most effective when the system model is well-parameterized, suggesting potential applications in synthetic biology where standardized biological parts are available. However, further research is necessary to develop computationally tractable approximations to the exact generalized solution presented here.

  13. 4D reconstruction of soil surface changes with time-lapse cameras

    Science.gov (United States)

    Eltner, Anette; Kaiser, Andreas; Schindewolf, Marcus

    2017-04-01

    Time-lapse photogrammetry enables fascinating visual insights into earth surface processes by compressing time. Recent advances in spatially high resolution topographic data are made possible due to Structure-from-Motion (SfM) photogrammetry. In a next step increasing the temporal resolution can allow for continuous 4D monitoring of soil surface processes. Two case studies are presented where 4D reconstruction is performed utilising a time-lapse system with a multi-angle camera setup of three SLR cameras, which enables repeated calculation of digital elevation models (DEMs) of difference. A thunderstorm event was captured at a field with 15 seconds interval and a rainfall simulation has been observed at plot scale with a temporal resolution of 10 seconds. A workflow is introduced for fully automatic data generation. Thereby, special care needs to be taken regarding camera calibration and subsequent image correction. Furthermore, camera movements are compensated for via template matching of stable ground control points. In addition, temporal filtering is applied to the resulting surface change models to account for random noise and to increase the reliability of the measurement of signals of change with low intensity. Results reveal significant surface changes during the events. Ripple and pool sequences become obvious in both case studies. Additionally, roughness changes and hydrostatic effects are apparent along the temporal domain at the plot scale.

  14. Comparative evaluation of performance measures for shading correction in time-lapse fluorescence microscopy.

    Science.gov (United States)

    Liu, L; Kan, A; Leckie, C; Hodgkin, P D

    2017-04-01

    Time-lapse fluorescence microscopy is a valuable technology in cell biology, but it suffers from the inherent problem of intensity inhomogeneity due to uneven illumination or camera nonlinearity, known as shading artefacts. This will lead to inaccurate estimates of single-cell features such as average and total intensity. Numerous shading correction methods have been proposed to remove this effect. In order to compare the performance of different methods, many quantitative performance measures have been developed. However, there is little discussion about which performance measure should be generally applied for evaluation on real data, where the ground truth is absent. In this paper, the state-of-the-art shading correction methods and performance evaluation methods are reviewed. We implement 10 popular shading correction methods on two artificial datasets and four real ones. In order to make an objective comparison between those methods, we employ a number of quantitative performance measures. Extensive validation demonstrates that the coefficient of joint variation (CJV) is the most applicable measure in time-lapse fluorescence images. Based on this measure, we have proposed a novel shading correction method that performs better compared to well-established methods for a range of real data tested. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.

  15. An Analytical Formula for Potential Water Vapor in an Atmosphere of Constant Lapse Rate

    Directory of Open Access Journals (Sweden)

    Ali Varmaghani

    2012-01-01

    Full Text Available Accurate calculation of precipitable water vapor (PWV in the atmosphere has always been a matter of importance for meteorologists. Potential water vapor (POWV or maximum precipitable water vapor can be an appropriate base for estimation of probable maximum precipitation (PMP in an area, leading to probable maximum flood (PMF and flash flood management systems. PWV and POWV have miscellaneously been estimated by means of either discrete solutions such as tables, diagrams or empirical methods; however, there is no analytical formula for POWV even in a particular atmospherical condition. In this article, fundamental governing equations required for analytical calculation of POWV are first introduced. Then, it will be shown that this POWV calculation relies on a Riemann integral solution over a range of altitude whose integrand is merely a function of altitude. The solution of the integral gives rise to a series function which is bypassed by approximation of saturation vapor pressure in the range of -55 to 55 degrees Celsius, and an analytical formula for POWV in an atmosphere of constant lapse rate is proposed. In order to evaluate the accuracy of the suggested equation, exact calculations of saturated adiabatic lapse rate (SALR at different surface temperatures were performed. The formula was compared with both the diagrams from the US Weather Bureau and SALR. The results demonstrated unquestionable capability of analytical solutions and also equivalent functions.

  16. Stochastic modeling of oligodendrocyte generation in cell culture: model validation with time-lapse data

    Directory of Open Access Journals (Sweden)

    Noble Mark

    2006-05-01

    Full Text Available Abstract Background The purpose of this paper is two-fold. The first objective is to validate the assumptions behind a stochastic model developed earlier by these authors to describe oligodendrocyte generation in cell culture. The second is to generate time-lapse data that may help biomathematicians to build stochastic models of cell proliferation and differentiation under other experimental scenarios. Results Using time-lapse video recording it is possible to follow the individual evolutions of different cells within each clone. This experimental technique is very laborious and cannot replace model-based quantitative inference from clonal data. However, it is unrivalled in validating the structure of a stochastic model intended to describe cell proliferation and differentiation at the clonal level. In this paper, such data are reported and analyzed for oligodendrocyte precursor cells cultured in vitro. Conclusion The results strongly support the validity of the most basic assumptions underpinning the previously proposed model of oligodendrocyte development in cell culture. However, there are some discrepancies; the most important is that the contribution of progenitor cell death to cell kinetics in this experimental system has been underestimated.

  17. Time-Lapse Electrical Resistivity Investigations for Imaging the Grouting Injection in Shallow Subsurface Cavities

    Directory of Open Access Journals (Sweden)

    Muhammad Farooq

    2014-01-01

    Full Text Available The highway of Yongweol-ri, Muan-gun, south-western part of the South Korean Peninsula, is underlain by the abandoned of subsurface cavities, which were discovered in 2005. These cavities lie at shallow depths with the range of 5∼15 meters below the ground surface. Numerous subsidence events have repeatedly occurred in the past few years, damaging infrastructure and highway. As a result of continuing subsidence issues, the Korean Institute of Geosciences and Mineral Resources (KIGAM was requested by local administration to resolve the issue. The KIGAM used geophysical methods to delineate subsurface cavities and improve more refined understanding of the cavities network in the study area. Cement based grouting has been widely employed in the construction industry to reinforce subsurface ground. In this research work, time-lapse electrical resistivity surveys were accomplished to monitor the grouting injection in the subsurface cavities beneath the highway, which have provided a quasi-real-time monitoring for modifying the subsurface cavities related to ground reinforcement, which would be difficult with direct methods. The results obtained from time-lapse electrical resistivity technique have satisfactory imaged the grouting injection experiment in the subsurface cavities beneath the highway. Furthermore, the borehole camera confirmed the presence of grouting material in the subsurface cavities, and hence this procedure increases the mechanical resistance of subsurface cavities below the highway.

  18. Alcohol and sleep restriction combined reduces vigilant attention, whereas sleep restriction alone enhances distractibility.

    Science.gov (United States)

    Lee, James; Manousakis, Jessica; Fielding, Joanne; Anderson, Clare

    2015-05-01

    Alcohol and sleep loss are leading causes of motor vehicle crashes, whereby attention failure is a core causal factor. Despite a plethora of data describing the effect of alcohol and sleep loss on vigilant attention, little is known about their effect on voluntary and involuntary visual attention processes. Repeated-measures, counterbalanced design. Controlled laboratory setting. Sixteen young (18-27 y; M = 21.90 ± 0.60 y) healthy males. Participants completed an attention test battery during the afternoon (13:00-14:00) under four counterbalanced conditions: (1) baseline; (2) alcohol (0.05% breath alcohol concentration); (3) sleep restriction (02:00-07:00); and (4) alcohol/sleep restriction combined. This test battery included a Psychomotor Vigilance Task (PVT) as a measure of vigilant attention, and two ocular motor tasks-visually guided and antisaccade-to measure the involuntary and voluntary allocation of visual attention. Only the combined condition led to reductions in vigilant attention characterized by slower mean reaction time, fastest 10% responses, and increased number of lapses (P Sleep restriction alone however increased both antisaccade inhibitory errors [45.8% errors versus 185.0 msec all others) to a peripheral target (P sleep related attention failure: the voluntary allocation of attention is impaired, whereas the involuntary allocation of attention is enhanced. This provides key evidence for the role of distraction in attention failure during sleep loss. © 2015 Associated Professional Sleep Societies, LLC.

  19. Harmonic oscillator in heat bath: Exact simulation of time-lapse-recorded data and exact analytical benchmark statistics

    DEFF Research Database (Denmark)

    Nørrelykke, Simon F; Flyvbjerg, Henrik

    2011-01-01

    -lapse recordings. Three applications are discussed: (i) The effects of finite sampling rate and time, described exactly here, are similar for other stochastic dynamical systems-e.g., motile microorganisms and their time-lapse-recorded trajectories. (ii) The same statistics is satisfied by any experimental system......The stochastic dynamics of the damped harmonic oscillator in a heat bath is simulated with an algorithm that is exact for time steps of arbitrary size. Exact analytical results are given for correlation functions and power spectra in the form they acquire when computed from experimental time...... of finite sampling rate and sampling time for these models as well....

  20. Selected time-lapse movies of the east rift zone eruption of KĪlauea Volcano, 2004–2008

    Science.gov (United States)

    Orr, Tim R.

    2011-01-01

    Since 2004, the U.S. Geological Survey's Hawaiian Volcano Observatory has used mass-market digital time-lapse cameras and network-enabled Webcams for visual monitoring and research. The 26 time-lapse movies in this report were selected from the vast collection of images acquired by these camera systems during 2004–2008. Chosen for their content and broad aesthetic appeal, these image sequences document a variety of flow-field and vent processes from Kīlauea's east rift zone eruption, which began in 1983 and is still (as of 2011) ongoing.

  1. Attention Mosaics: Studies of Organizational Attention

    NARCIS (Netherlands)

    L. Carvalho de Mesquita Ferreira (Luciana)

    2010-01-01

    textabstractOrganizational studies emphasizing the role of attention in organizational behavior depart from the idea that organizations, like individuals, have limited capacity to attend to environmental stimuli. The bounded capacity of the organizations to respond to stimuli is conditioned by the

  2. Attention to Advertising

    OpenAIRE

    Nilsson, Carl Patrik

    2006-01-01

    Attention to Advertising Carl Patrik Nilsson, Umeå School of Business, Umeå University SE-901 87 Umeå, Sweden Abstract In advertising, capturing consumers’ attention is imperative. Yet, how attention to advertising works in a World Wide Web context has not been researched extensively. This area is the main focus of this research. The World Wide Web is an interactive medium which has characteristics that deviate from traditional media channels. Considering the unique properties of the World Wi...

  3. Announcements to Attentive Agents

    DEFF Research Database (Denmark)

    Bolander, Thomas; van Ditmarsch, Hans; Herzig, Andreas

    2016-01-01

    In public announcement logic it is assumed that all agents pay attention to the announcement. Weaker observational conditions can be modelled in action model logic. In this work, we propose a version of public announcement logic wherein it is encoded in the states of the epistemic model which...... agents pay attention to the announcement. This logic is called attention-based announcement logic. We give an axiomatization of the logic and prove that complexity of satisfiability is the same as that of public announcement logic, and therefore lower than that of action model logic. An attention...

  4. Time-lapse VSP data processing for monitoring CO2 injection

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Lianjie [Los Alamos National Laboratory; Rutledge, James [Los Alamos National Laboratory; Cheng, Arthur [CAMBRIDGE GEOSCIENCES

    2009-01-01

    As a part of the effort of the Southwest Regional Partnership on Carbon Sequestration supported by U.S. Department of Energy and managed by the National Energy Technology Laboratory, two sets of time-lapse VSPs were acquired and processed in oil fields undergoing CO{sub 2} injection. One set of VSPs was acquired at the Aneth oil field in Utah, the other set at the Scurry Area Canyon Reef Operators Committee (SACROC) field in West Texas. One baseline and two repeat VSP surveys were conducted from 2007 to 2009 at the Aneth oil field in Utah for monitoring CO{sub 2} injection. The aim of the time-lapse VSP surveys is to study the combined enhanced oil recovery (EOR) and CO{sub 2} sequestration in collaboration with Resolute Natural Resources, Inc. VSP data were acquired using a cemented geophone string with 60 levels at depth from 805 m to 1704 m, and CO{sub 2} is injected into a horizontal well nearby within the reservoir at depth approximately from 1730 m to 1780 m. For each VSP survey, the data were acquired for one zero-offset source location and seven offset source locations (Figure 1). The baseline VSP survey was conducted before the CO{sub 2} injection. More than ten thousand tons of CO{sub 2} was injected between each of the two repeat VSP surveys. There are three horizontal injection wells, all originating from the same vertical well. One is drilled towards Southeast, directly towards the monitoring well (Figure 2), and the other two towards Northwest, directly away from the monitoring well. The injection is into the top portion of the Desert Creek formation, just beneath the Gothic shale, which acts as the reservoir seal. The initial baseline acquisition was done in October 2007; subsequent time-lapse acquisitions were conducted in July 2008, and January 2009. The acquisition geometry is shown in Figure 1. Shot point 1 is the zero-offset source location, Shot points 2 to 8 are the seven offset VSPs, arranged in a quarter circle on the Northwest side of the

  5. Laughter catches attention!

    NARCIS (Netherlands)

    Pinheiro, Ana P; Barros, Carla; Dias, Marcelo; Kotz, Sonja A

    2017-01-01

    In social interactions, emotionally salient and sudden changes in vocal expressions attract attention. However, only a few studies examined how emotion and attention interact in voice processing. We investigated neutral, happy (laughs) and angry (growls) vocalizations in a modified oddball task.

  6. Unmasking the attentional blink

    NARCIS (Netherlands)

    Nieuwenstein, Mark R.; Potter, Mary C.; Theeuwes, Jan

    2009-01-01

    When asked to identify 2 visual targets (T I and T2 for the 1st and 2nd targets. respectively) embedded in a sequence of distractors, observers will often fail to identify T2 when it appears within 200-500 Ins of T1-an effect called the attentional blink. Recent work shows that attention does not

  7. Neural Mechanisms of Attention

    Science.gov (United States)

    1993-05-21

    attention deficit hyperactivity disorder ( ADHD ). These disorders may encompass a number of other cognitive deficits, but many theories focus on the...trial of methylphenidate in black adolescents. Attentional, behavioral, and physiological effects. CLINICAL.PEDIATRICS., 27,74-81. Bruto, V...Nakamura, K., Nishijo, H., & Fukuda, M. (1986). Hypothalamic neuron involvement in integration of reward , aversion, and cue signals. Journal of

  8. Analyzing dynamic cellular morphology in time-lapsed images enabled by cellular deformation pattern recognition.

    Science.gov (United States)

    Li, Heng; Liu, Zhiwen; Pang, Fengqian; Fan, Zhiyi; Shi, Yonggang

    2015-01-01

    Computational analysis of cellular morphology aims to provide quantitative information of the global organizational and physiological state of cells, and has long been a major topic of biomedical research. Instead of analyzing morphology of static cells, we concentrate on live-cell deformation in a period of time. According to our observation of dynamic cell behavior, we have assumed that the pattern of cellular deformation is relevant to the cellular state. Moreover, based on our assumption an innovative approach for characterizing the deformation pattern is described and applied into cell classification. After normalizing and aligning cell image sequences, we extract the continuity of deformation at each angle through time-lapse. Then the deformation pattern is given by the histogram of the continuity of deformation. Experimental results demonstrate that the cellular deformation pattern provided by our approach can be applied to discriminate cellular activation. In addition, the deformation pattern recognition makes remarkable progress in the classification of cells.

  9. In vivo time-lapse imaging and serial section electron microscopy reveal developmental synaptic rearrangements

    Science.gov (United States)

    Li, Jianli; Erisir, Alev; Cline, Hollis

    2010-01-01

    Dendrites, axons and synapses are dynamic during circuit development, however changes in microcircuit connections as branches stabilize have not been directly demonstrated. By combining in vivo time-lapse imaging of Xenopus tectal neurons with electron microscope reconstructions of imaged neurons, we report for the first time the distribution and ultrastructure of synapses on individual vertebrate neurons and relate these synaptic properties to dynamics in dendritic and axonal arbor structure over hours or days of imaging. Dynamic dendrites have a high density of immature synapses whereas stable dendrites have sparser, mature synapses. Axons initiate contacts from multisynapse boutons on stable branches. Connections are refined by decreasing convergence from multiple inputs to postsynaptic dendrites and by decreasing divergence from multisynapse boutons to postsynaptic sites. Visual deprivation or NMDAR antagonists decreased synapse maturation and elimination, suggesting that coactive input activity promotes microcircuit development by concurrently regulating synapse elimination and maturation of remaining contacts. PMID:21262466

  10. Optimal Estimation of Diffusion Coefficients from Noisy Time-Lapse-Recorded Single-Particle Trajectories

    DEFF Research Database (Denmark)

    Vestergaard, Christian Lyngby

    2012-01-01

    Optimal Estimation of Diusion Coecients from Noisy Time-Lapse- Measurements of Single-Particle Trajectories Single-particle tracking techniques allow quantitative measurements of diusion at the single-molecule level. Recorded time-series are mostly short and contain considerable measurement noise...... estimator for the diusion coecient, valid for short time-series, along with an exact benchmark for the maximum precision attainable with any unbiased estimator, the Cramer-Rao bound. We propose a simple analytical and unbiased covariance-based estimator based on the autocovariance function and derive...... of diusion coecients of hOgg1 repair proteins diusing on stretched uctuating DNA from data previously analyzed using a suboptimal method. Our analysis shows that the proteins have dierent eective diusion coecients and that their diusion coecients are correlated with their residence time on DNA. These results...

  11. 3-D time-lapse electrical resistivity monitoring of injected CO2 in a shallow aquifer

    DEFF Research Database (Denmark)

    Doetsch, Joseph A. J.A.; Auken, Esben; Christiansen, Anders Vest C A.V.C.

    2013-01-01

    Contamination of potable groundwater by leaking CO2 is a potential risk of carbon sequestration. With the help of a field experiment, we investigate if surface electrical resistivity tomography (ERT) can detect dissolved CO2 in a shallow aquifer. For this purpose, we injected CO2 at a depth of 5...... and 10 m and monitored its migration using 320 surface electrodes on a 126 m × 20 m grid. A fully automated acquisition system continuously collected data and uploaded it into an online database. The large amount of data allows for time-series analysis for data quality and noise estimation. A baseline...... inversion reveals the geology at the site consisting of aeolian sands near the surface and glacial sands below 5 m depth. Time-lapse inversions clearly image the dissolved CO2 plume with decreased electrical resistivity values. We can follow the CO2 plume as it spreads and moves with the groundwater...

  12. In vivo time-lapse imaging of mitochondria in healthy and diseased peripheral myelin sheath.

    Science.gov (United States)

    Gonzalez, Sergio; Fernando, Ruani; Berthelot, Jade; Perrin-Tricaud, Claire; Sarzi, Emmanuelle; Chrast, Roman; Lenaers, Guy; Tricaud, Nicolas

    2015-07-01

    The myelin sheath that covers a large amount of neurons is critical for their homeostasis, and myelinating glia mitochondria have recently been shown to be essential for neuron survival. However morphological and physiological properties of these organelles remain elusive. Here we report a method to analyze mitochondrial dynamics and morphology in myelinating Schwann cells of living mice using viral transduction and time-lapse multiphoton microscopy. We describe the distribution, shape, size and dynamics of mitochondria in live cells. We also report mitochondrial alterations in Opa1(delTTAG) mutant mice cells at presymptomatic stages, suggesting that mitochondrial defects in myelin contribute to OPA1 related neuropathy and represent a biomarker for the disease. Copyright © 2015 © Elsevier B.V. and Mitochondria Research Society. Published by Elsevier B.V. All rights reserved.

  13. Optimal Live Cell Tracking for Cell Cycle Study Using Time-Lapse Fluorescent Microscopy Images

    Science.gov (United States)

    Li, Fuhai; Zhou, Xiaobo; Wong, Stephen T. C.

    Cell cycle study using time-lapse fluorescent microscopy images is important for understanding the mechanisms of cell division and screening of anti-cancer drugs. Cell tracking is necessary for quantifying cell behaviors. However, the complex behaviors and similarity of individual cells in a dense population make the cell population tracking challenging. To deal with these challenges, we propose a novel tracking algorithm, in which the local neighboring information is introduced to distinguish the nearby cells with similar morphology, and the Interacting Multiple Model (IMM) filter is employed to compensate for cell migrations. Based on a similarity metric, integrating the local neighboring information, migration prediction, shape and intensity, the integer programming is used to achieve the most stable association between cells in two consecutive frames. We evaluated the proposed method on the high content screening assays of HeLa cancer cell populations, and achieved 92% average tracking accuracy.

  14. Time-lapse seismic analysis of the North Sea Fulmar Field

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, David H.; McKenny, Robert S.; Burkhart, Tucker D.

    1998-12-31

    Time-lapse seismic analysis has been applied to two 3-D seismic surveys acquired over the central North Sea Fulmar field in a pre-production survey shot in 1977, reprocessed in 1987, and a survey in 1992. The Upper Jurassic reservoirs in the field have been under production since 1982. Differences in averaged impedance between the 1977 and 1992 surveys clearly show the effects of water influx and pressure decline. The changes observed in the seismic data are overall consistent with predictions obtained from a full-field, history-matched simulation. Differences in details may suggest areas of bypassed oil. Dta quality is not sufficient to serve as the sole basis for drilling decisions. 1 ref., 6 figs.

  15. [Assessing the effect of compulsory ambulatory treatment orders on the time lapse out of hospitalization for patients suffering from schizophrenia].

    Science.gov (United States)

    Spinzy, Yaniv; Israel, Krieger

    2012-03-01

    Schizophrenia is the most severe mental disorder, characterized in many cases by poor insight and low adherence to drug treatment. In Israel, as in many countries, Laws have been Legislated to allow the issuance of compuLsory ambulatory treatment orders (CATO) to patients whose medical condition poses a risk to themselves or the environment. In the Limited existing literature, no conclusive evidence has been found on the efficacy of CATO on patients' outcome. We examined the medical files of all the patients in "Shalvata" Mental Health Center, who were treated under the compulsory ambulatory treatment order during the years 2003-2010. We examined the effect of the CATO on the time Lapse out of hospitalization during a 3 year period before and after issuing the order. The study group was composed of 77 patients and each patient served as his own control. We conducted paired samples t-test and found that the average time lapse out of hospitalization after issuing CATO was higher (M = 426 days, SD = 3921 compared to the average time lapse out of hospitalization before issuing CATO (M = 345 days, SD = 366, N = 77), but the difference was not statistically significant (t = -1.34, p = 0.2). Our research shows that there was no significant beneficial effect of the CATO in the group of patients that we examined. We found that the average time lapse out of hospitalization did not increase significantly. Our study raises questions regarding the importance of the compulsory ambulatory treatment and its implementation measures.

  16. Joint inversion of time-lapse VSP data for monitoring CO2 injection at the Farnsworth EOR field in Texas

    Science.gov (United States)

    Zhang, M.; Gao, K.; Balch, R. S.; Huang, L.

    2016-12-01

    During the Development Phase (Phase III) of the U.S. Southwest Regional Partnership on Carbon Sequestration (SWP), time-lapse 3D vertical seismic profiling (VSP) data were acquired to monitor CO2 injection/migration at the Farnsworth Enhanced Oil Recovery (EOR) field, in partnership with the industrial partner Chaparral Energy. The project is to inject a million tons of carbon dioxide into the target formation, the deep oil-bearing Morrow Formation in the Farnsworth Unit EOR field. Quantitative time-lapse seismic monitoring has the potential to track CO2 movement in geologic carbon storage sites. Los Alamos National Laboratory (LANL) has recently developed new full-waveform inversion methods to jointly invert time-lapse seismic data for changes in elastic and anisotropic parameters in target monitoring regions such as a CO2 reservoir. We apply our new joint inversion methods to time-lapse VSP data acquired at the Farnsworth EOR filed, and present some preliminary results showing geophysical properties changes in the reservoir.

  17. Time-lapse micro-tomography analysis of the deformation response of a gellan-gum-based scaffold

    Czech Academy of Sciences Publication Activity Database

    Kytýř, Daniel; Fenclová, Nela; Zlámal, Petr; Kumpová, Ivana; Fíla, Tomáš; Koudelka_ml., Petr; Gantar, A.; Novak, S.

    2017-01-01

    Roč. 51, č. 3 (2017), s. 397-402 ISSN 1580-2949 Institutional support: RVO:68378297 Keywords : bone scaffold * gellan gum * time-lapse micro CT * digital volume correlation Subject RIV: JJ - Other Materials Impact factor: 0.436, year: 2016 http://mit.imt.si/Revija/izvodi/mit173/kytyr.pdf

  18. How to connect time-lapse recorded trajectories of motile microorganisms with dynamical models in continuous time

    DEFF Research Database (Denmark)

    Pedersen, Jonas Nyvold; Li, Liang; Gradinaru, Cristian

    2016-01-01

    We provide a tool for data-driven modeling of motility, data being time-lapse recorded trajectories. Several mathematical properties of a model to be found can be gleaned from appropriate model-independent experimental statistics, if one understands how such statistics are distorted by the finite...

  19. Bayesian Markov chain Monte Carlo Inversion of Time-Lapse Geophysical Data To Characterize the Vadose Zone

    DEFF Research Database (Denmark)

    Scholer, Marie; Irving, James; Zibar, Majken Caroline Looms

    Geophysical methods have the potential to provide valuable information on hydrological properties in the unsaturated zone. In particular, time-lapse geophysical data, when coupled with a hydrological model and inverted stochastically, may allow for the effective estimation of subsurface hydraulic...

  20. Growth Rate and Morphology of a Single Calcium Carbonate Crystal on Polysulfone Film Measured with Time Lapse Raman Micro Spectroscopy

    NARCIS (Netherlands)

    Liszka, B.; Lenferink, Aufrid T.M.; Otto, Cornelis

    2016-01-01

    The growth of single, self- nucleated calcium carbonate crystals on a polysulfone (PSU) film was investigated with high resolution, time lapse Raman imaging. The Raman images were acquired on the interface of the polymer with the crystal. The growth of crystals could thus be followed in time. PSU is

  1. Time-Lapse Joint Inversion of Cross-Well DC Resistivity and Seismic Data: A Numerical Investigation

    Science.gov (United States)

    Time-lapse joint inversion of geophysical data is required to image the evolution of oil reservoirs during production and enhanced oil recovery, CO2 sequestration, geothermal fields during production, and to monitor the evolution of contaminant plumes. Joint inversion schemes red...

  2. Attention and choice

    DEFF Research Database (Denmark)

    Orquin, Jacob Lund; Mueller Loose, Simone

    2013-01-01

    This paper reviews studies on eye movements in decision making, and compares their observations to theoretical predictions concerning the role of attention in decision making. Four decision theories are examined: rational models, bounded rationality, evidence accumulation, and parallel constraint...... satisfaction models. Although most theories were confirmed with regard to certain predictions, none of the theories adequately accounted for the role of attention during decision making. Several observations emerged concerning the drivers and down-stream effects of attention on choice, suggesting...... that attention processes plays an active role in constructing decisions. So far, decision theories have largely ignored the constructive role of attention by assuming that it is entirely determined by heuristics, or that it consists of stochastic information sampling. The empirical observations reveal...

  3. Low-Cost Motility Tracking System (LOCOMOTIS) for Time-Lapse Microscopy Applications and Cell Visualisation

    Science.gov (United States)

    Lynch, Adam E.; Triajianto, Junian; Routledge, Edwin

    2014-01-01

    Direct visualisation of cells for the purpose of studying their motility has typically required expensive microscopy equipment. However, recent advances in digital sensors mean that it is now possible to image cells for a fraction of the price of a standard microscope. Along with low-cost imaging there has also been a large increase in the availability of high quality, open-source analysis programs. In this study we describe the development and performance of an expandable cell motility system employing inexpensive, commercially available digital USB microscopes to image various cell types using time-lapse and perform tracking assays in proof-of-concept experiments. With this system we were able to measure and record three separate assays simultaneously on one personal computer using identical microscopes, and obtained tracking results comparable in quality to those from other studies that used standard, more expensive, equipment. The microscopes used in our system were capable of a maximum magnification of 413.6×. Although resolution was lower than that of a standard inverted microscope we found this difference to be indistinguishable at the magnification chosen for cell tracking experiments (206.8×). In preliminary cell culture experiments using our system, velocities (mean µm/min ± SE) of 0.81±0.01 (Biomphalaria glabrata hemocytes on uncoated plates), 1.17±0.004 (MDA-MB-231 breast cancer cells), 1.24±0.006 (SC5 mouse Sertoli cells) and 2.21±0.01 (B. glabrata hemocytes on Poly-L-Lysine coated plates), were measured and are consistent with previous reports. We believe that this system, coupled with open-source analysis software, demonstrates that higher throughput time-lapse imaging of cells for the purpose of studying motility can be an affordable option for all researchers. PMID:25121722

  4. Spectral-element simulations of carbon dioxide (CO2) sequestration time-lapse monitoring

    Science.gov (United States)

    Morency, C.; Luo, Y.; Tromp, J.

    2009-12-01

    Geologic sequestration of CO2, a green house gas, represents an effort to reduce the large amount of CO2 generated as a by-product of fossil fuels combustion and emitted into the atmosphere. This process of sequestration involves CO2 storage deep underground. There are three main storage options: injection into hydrocarbon reservoirs, injection into methane-bearing coal beds, or injection into deep saline aquifers, that is, highly permeable porous media. The key issues involve accurate monitoring of the CO2, from the injection stage to the prediction & verification of CO2 movement over time for environmental considerations. A natural non-intrusive monitoring technique is referred to as ``4D seismics'', which involves 3D time-lapse seismic surveys. The success of monitoring the CO2 movement is subject to a proper description of the physics of the problem. We propose to realize time-lapse migrations comparing acoustic, elastic, and poroelastic simulations of 4D seismic imaging to characterize the storage zone. This approach highlights the influence of using different physical theories on interpreting seismic data, and, more importantly, on extracting the CO2 signature from the seismic wave field. Our simulations are performed using a spectral-element method, which allows for highly accurate results. Biot's equations are implemented to account for poroelastic effects. Attenuation associated with the anelasticity of the rock frame and frequency-dependent viscous resistance of the pore fluid are accommodated based upon a memory variable approach. The sensitivity of observables to the model parameters is quantified based upon finite-frequency sensitivity kernels calculated using an adjoint method.

  5. Time-lapse imaging of red blood cell invasion by the rodent malaria parasite Plasmodium yoelii.

    Directory of Open Access Journals (Sweden)

    Kazuhide Yahata

    Full Text Available In order to propagate within the mammalian host, malaria parasites must invade red blood cells (RBCs. This process offers a window of opportunity in which to target the parasite with drugs or vaccines. However, most of the studies relating to RBC invasion have analyzed the molecular interactions of parasite proteins with host cells under static conditions, and the dynamics of these interactions remain largely unstudied. Time-lapse imaging of RBC invasion is a powerful technique to investigate cell invasion and has been reported for Plasmodium knowlesi and Plasmodium falciparum. However, experimental modification of genetic loci is laborious and time consuming for these species. We have established a system of time-lapse imaging for the rodent malaria parasite Plasmodium yoelii, for which modification of genetic loci is quicker and simpler. We compared the kinetics of RBC invasion by P. yoelii with that of P. falciparum and found that the overall kinetics during invasion were similar, with some exceptions. The most striking of these differences is that, following egress from the RBC, the shape of P. yoelii merozoites gradually changes from flat elongated ovals to spherical bodies, a process taking about 60 sec. During this period merozoites were able to attach to and deform the RBC membrane, but were not able to reorient and invade. We propose that this morphological change of P. yoelii merozoites may be related to the secretion or activation of invasion-related proteins. Thus the P. yoelii merozoite appears to be an excellent model to analyze the molecular dynamics of RBC invasion, particularly during the morphological transition phase, which could serve as an expanded window that cannot be observed in P. falciparum.

  6. Gliding motility of Babesia bovis merozoites visualized by time-lapse video microscopy.

    Directory of Open Access Journals (Sweden)

    Masahito Asada

    Full Text Available BACKGROUND: Babesia bovis is an apicomplexan intraerythrocytic protozoan parasite that induces babesiosis in cattle after transmission by ticks. During specific stages of the apicomplexan parasite lifecycle, such as the sporozoites of Plasmodium falciparum and tachyzoites of Toxoplasma gondii, host cells are targeted for invasion using a unique, active process termed "gliding motility". However, it is not thoroughly understood how the merozoites of B. bovis target and invade host red blood cells (RBCs, and gliding motility has so far not been observed in the parasite. METHODOLOGY/PRINCIPAL FINDINGS: Gliding motility of B. bovis merozoites was revealed by time-lapse video microscopy. The recorded images revealed that the process included egress of the merozoites from the infected RBC, gliding motility, and subsequent invasion into new RBCs. The gliding motility of B. bovis merozoites was similar to the helical gliding of Toxoplasma tachyzoites. The trails left by the merozoites were detected by indirect immunofluorescence assay using antiserum against B. bovis merozoite surface antigen 1. Inhibition of gliding motility by actin filament polymerization or depolymerization indicated that the gliding motility was driven by actomyosin dependent process. In addition, we revealed the timing of breakdown of the parasitophorous vacuole. Time-lapse image analysis of membrane-stained bovine RBCs showed formation and breakdown of the parasitophorous vacuole within ten minutes of invasion. CONCLUSIONS/SIGNIFICANCE: This is the first report of the gliding motility of B. bovis. Since merozoites of Plasmodium parasites do not glide on a substrate, the gliding motility of B. bovis merozoites is a notable finding.

  7. Quantifying Effusion Rates at Active Volcanoes through Integrated Time-Lapse Laser Scanning and Photography

    Directory of Open Access Journals (Sweden)

    Neil Slatcher

    2015-11-01

    Full Text Available During volcanic eruptions, measurements of the rate at which magma is erupted underpin hazard assessments. For eruptions dominated by the effusion of lava, estimates are often made using satellite data; here, in a case study at Mount Etna (Sicily, we make the first measurements based on terrestrial laser scanning (TLS, and we also include explosive products. During the study period (17–21 July 2012, regular Strombolian explosions were occurring within the Bocca Nuova crater, producing a ~50 m-high scoria cone and a small lava flow field. TLS surveys over multi-day intervals determined a mean cone growth rate (effusive and explosive products of ~0.24 m3·s−1. Differences between 0.3-m resolution DEMs acquired at 10-minute intervals captured the evolution of a breakout lava flow lobe advancing at 0.01–0.03 m3·s−1. Partial occlusion within the crater prevented similar measurement of the main flow, but integrating TLS data with time-lapse imagery enabled lava viscosity (7.4 × 105 Pa·s to be derived from surface velocities and, hence, a flux of 0.11 m3·s−1 to be calculated. Total dense rock equivalent magma discharge estimates are ~0.1–0.2 m3·s−1 over the measurement period and suggest that simultaneous estimates from satellite data are somewhat overestimated. Our results support the use of integrated TLS and time-lapse photography for ground-truthing space-based measurements and highlight the value of interactive image analysis when automated approaches, such as particle image velocimetry (PIV, fail.

  8. Limiting aspects of using geophysical time-lapse measurements for contaminant site monitoring

    Science.gov (United States)

    French, H. K.; Bloem, E.

    2010-12-01

    Winter maintenance at airports and roads in the areas with winter frost requires the use of large quantities of de-icing chemicals. These chemicals infiltrate the unsaturated zone during winter and spring due to the mixing with snow next to the roads or runways and may hence pollute the groundwater. Geophysical methods provide insight into soil heterogeneity and characteristics and may, when used in time-lapse mode, serve as a monitoring technique for contaminant transport over larger areas than traditional sampling techniques such as suction cups, soil sampling techniques and groundwater wells. The presence of a mixture of materials and contaminants in the subsurface, as well as the natural temporal variable conditions such as temperature and water saturation are among the challenges of geophysical monitoring of flow and transport processes in the unsaturated zone. Some examples of the use of geophysical measurements for contaminant site monitoring from the literature will be given as well as insight to more specific challenges both practical and scientifically for a case study in Norway. The case study shows results of electrical resistivity measurements along two profiles next to one of the runways at Oslo airport, Gardermoen. One profile is located parallel to the runway and within the zone affected by contaminated snow, while the other set of surface electrodes are installed at an angle from the runway and covers areas both affected and unaffected by de-icing chemicals. In addition to time-lapse electrical resistivity measurements, the soil temperature, volumetric water content and the electrical conductivity of the soil water is measured at 4 depths at the crossing point of the two cables. Theoretical improvements and managerial aspects still required for the applicability of this monitoring technique at contaminated sites will be discussed.

  9. On the Resolvability of Steam Assisted Gravity Drainage Reservoirs Using Time-Lapse Gravity Gradiometry

    Science.gov (United States)

    Elliott, E. Judith; Braun, Alexander

    2017-11-01

    Unconventional heavy oil resource plays are important contributors to oil and gas production, as well as controversial for posing environmental hazards. Monitoring those reservoirs before, during, and after operations would assist both the optimization of economic benefits and the mitigation of potential environmental hazards. This study investigates how gravity gradiometry using superconducting gravimeters could resolve depletion areas in steam assisted gravity drainage (SAGD) reservoirs. This is achieved through modelling of a SAGD reservoir at 1.25 and 5 years of operation. Specifically, the density change structure identified from geological, petrological, and seismic observations is forward modelled for gravity and gradients. Three main parameters have an impact on the resolvability of bitumen depletion volumes and are varied through a suitable parameter space: well pair separation, depth to the well pairs, and survey grid sampling. The results include a resolvability matrix, which identifies reservoirs that could benefit from time-lapse gravity gradiometry monitoring. After 1.25 years of operation, during the rising phase, the resolvable maximum reservoir depth ranges between the surface and 230 m, considering a well pair separation between 80 and 200 m. After 5 years of production, during the spreading phase, the resolvability of depletion volumes around single well pairs is greatly compromised as the depletion volume is closer to the surface, which translates to a larger portion of the gravity signal. The modelled resolvability matrices were derived from visual inspection and spectral analysis of the gravity gradient signatures and can be used to assess the applicability of time-lapse gradiometry to monitor reservoir density changes.

  10. Time-Lapse Monitoring of Soil Water Content Using Electromagnetic Conductivity Imaging

    Science.gov (United States)

    Triantafilis, J.; Huang, J.

    2016-12-01

    The volumetric soil water content (θ) is fundamental to agriculture because its spatio-temporal variation in soil affects plant growth. The universally accepted thermogravimetric method for estimating θ is labour intensive and time-consuming to use for field-scale monitoring. Electromagnetic (EM) induction has proven useful in mapping spatio-temporal variation of θ. However, depth-specific variation, which is important for irrigation management has been little explored. In this study we develop a relationship between θ and estimates of true electrical conductivity (σ) and use this to develop time-lapse images of θ beneath a center-pivot irrigated alfalfa (Medicago sativa L.) field in San Jacinto, California, USA. We measure the bulk apparent electrical conductivity (ECa - mS/m) using a DUALEM-421 over a period of 12 days after an irrigation event (i.e., days 1, 2, 3, 4, 6, 8 and 12). We use EM4Soil to generate electromagnetic conductivity images (EMCI). Testing the scenario where no soil information is available, we used a 3-parameter exponential model to relate θ to σ and then to map θ along the transect on different days. The results allow us to monitor the spatio-temporal variations of θ over the 12-day period. In this regard we were able to map the soil close to field capacity (0.27 cm3/cm3) and approaching permanent wilting point (0.03 cm3/cm3). The time-lapse θ monitoring approach, has implications for soil and water-use and management and allows farmers to identify inefficiencies in water application rates and use. It can also be used as a research tool to potentially assist precision irrigation practices and to test the efficacy of different methods of irrigation in terms of water delivery and efficiency in water use in near real-time.

  11. Proposed guidelines on the nomenclature and annotation of dynamic human embryo monitoring by a time-lapse user group.

    Science.gov (United States)

    Ciray, H Nadir; Campbell, Alison; Agerholm, Inge Errebo; Aguilar, Jesús; Chamayou, Sandrine; Esbert, Marga; Sayed, Shabana

    2014-12-01

    Can the approach to, and terminology for, time-lapse monitoring of preimplantation embryo development be uniformly defined in order to improve the utilization and impact of this novel technology? The adoption of the proposed guidelines for defining annotation practice and universal nomenclature would help unify time-lapse monitoring practice, allow validation of published embryo selection algorithms and facilitate progress in this field. An increasing quantity of publications and communications relating to time-lapse imaging of in vitro embryo development have demonstrated the added clinical value of morphokinetic data for embryo selection. Several articles have identified similar embryo selection or de-selection variables but have termed them differently. An evidence-based consensus document exists for static embryo grading and selection but, to date, no such reference document is available for time-lapse methodology or dynamic embryo grading and selection. A series of meetings were held between September 2011 and May 2014 involving time-lapse users from seven different European centres. The group reached consensus on commonly identified and novel time-lapse variables. Definitions, calculated variables and additional annotations for the dynamic monitoring of human preimplantation development were all documented. Guidelines are proposed for a standard methodology and terminology for the of use time-lapse monitoring of preimplantation embryo development. The time-lapse variables considered by this group may not be exhaustive. This is a relatively new clinical technology and it is likely that new variables will be introduced in time, requiring revised guidelines. A different group of users from those participating in this process may have yielded subtly different terms or definitions for some of the morphokinetic variables discussed. Due to the technical processes involved in time-lapse monitoring, and acquisition of images at varied intervals through limited focal

  12. Vanemate töötamine välismaal - kuidas see mõjutab lapse elu : laste ja spetsialistide tõlgendused / Helen Pärna, Karmen Lai, Taimi Tulva

    Index Scriptorium Estoniae

    Pärna, Helen, 1983-

    2008-01-01

    Artikkel tugineb Helen Pärna magistriuurimusele. Ülevaade uurimustulemustest, mis puudutavad välismaale tööle läinud lapsevanemate lapse toimetulekut argieluga ning arutletakse selle üle, kuidas lapse lahusolek vanematest võib mõjutada lapse ja vanema vahelisi suhteid

  13. Effects of depressive symptoms on antecedents of lapses during a smoking cessation attempt: an ecological momentary assessment study.

    Science.gov (United States)

    Brodbeck, Jeannette; Bachmann, Monica S; Brown, Anna; Znoj, Hans Joerg

    2014-08-01

    To investigate pathways through which momentary negative affect and depressive symptoms affect risk of lapse during smoking cessation attempts. Ecological momentary assessment was carried out during 2 weeks after an unassisted smoking cessation attempt. A 3-month follow-up measured smoking frequency. Data were collected via mobile devices in German-speaking Switzerland. A total of 242 individuals (age 20-40, 67% men) reported 7112 observations. Online surveys assessed baseline depressive symptoms and nicotine dependence. Real-time data on negative affect, physical withdrawal symptoms, urge to smoke, abstinence-related self-efficacy and lapses. A two-level structural equation model suggested that on the situational level, negative affect increased the urge to smoke and decreased self-efficacy (β = 0.20; β = -0.12, respectively), but had no direct effect on lapse risk. A higher urge to smoke (β = 0.09) and lower self-efficacy (β = -0.11) were confirmed as situational antecedents of lapses. Depressive symptoms at baseline were a strong predictor of a person's average negative affect (β = 0.35, all P depressive symptoms at baseline were associated strongly with a worse longer-term outcome. Negative affect experienced during the quit attempt was the only pathway through which the baseline depressive symptoms were associated with a reduced self-efficacy and increased urges to smoke, all leading to the increased probability of lapses. © 2014 Society for the Study of Addiction.

  14. BactImAS: a platform for processing and analysis of bacterial time-lapse microscopy movies.

    Science.gov (United States)

    Mekterović, Igor; Mekterović, Darko; Maglica, Zeljka

    2014-07-25

    The software available to date for analyzing image sequences from time-lapse microscopy works only for certain bacteria and under limited conditions. These programs, mostly MATLAB-based, fail for microbes with irregular shape, indistinct cell division sites, or that grow in closely packed microcolonies. Unfortunately, many organisms of interest have these characteristics, and analyzing their image sequences has been limited to time consuming manual processing. Here we describe BactImAS - a modular, multi-platform, open-source, Java-based software delivered both as a standalone program and as a plugin for Icy. The software is designed for extracting and visualizing quantitative data from bacterial time-lapse movies. BactImAS uses a semi-automated approach where the user defines initial cells, identifies cell division events, and, if necessary, manually corrects cell segmentation with the help of user-friendly GUI and incorporated ImageJ application. The program segments and tracks cells using a newly-developed algorithm designed for movies with difficult-to-segment cells that exhibit small frame-to-frame differences. Measurements are extracted from images in a configurable, automated fashion and an SQLite database is used to store, retrieve, and exchange all acquired data. Finally, the BactImAS can generate configurable lineage tree visualizations and export data as CSV files. We tested BactImAS on time-lapse movies of Mycobacterium smegmatis and achieved at least 10-fold reduction of processing time compared to manual analysis. We illustrate the power of the visualization tool by showing heterogeneity of both icl expression and cell growth atop of a lineage tree. The presented software simplifies quantitative analysis of time-lapse movies overall and is currently the only available software for the analysis of mycobacteria-like cells. It will be of interest to the community of both end-users and developers of time-lapse microscopy software.

  15. Are You Paying Attention?

    DEFF Research Database (Denmark)

    2016-01-01

    and sustained. To study such attention practices, 16 semi-structured interviews with adult Danes are carried out. Through a thematic analysis of these interviews, the chapter explores how ways of attending relate to individual media and how patterns of daily life enable some practices and constrain others......A still understudied area in media research is how people pay attention to news in daily life. To do so, the chapter develops a theoretical framework grounded in news audience research and practice theory. This framework conceptualizes practices as different ways in which attention is directed....... In the concluding discussion, the chapter relates the findings to further perspectives on attention to news specifically and media content more generally. Accordingly, this chapter contributes to cross-media news research by analyzing ways in which people attend to news and how these ways of attending vary across...

  16. Unmasking the Attentional Blink

    Science.gov (United States)

    Nieuwenstein, Mark R.; Potter, Mary C.; Theeuwes, Jan

    2009-01-01

    When asked to identify 2 visual targets (T1 and T2 for the 1st and 2nd targets, respectively) embedded in a sequence of distractors, observers will often fail to identify T2 when it appears within 200-500 ms of T1--an effect called the "attentional blink". Recent work shows that attention does not blink when the task is to encode a…

  17. Cognition, emotion, and attention.

    Science.gov (United States)

    Müller-Oehring, Eva M; Schulte, Tilman

    2014-01-01

    Deficits of attention, emotion, and cognition occur in individuals with alcohol abuse and addiction. This review elucidates the concepts of attention, emotion, and cognition and references research on the underlying neural networks and their compromise in alcohol use disorder. Neuroimaging research on adolescents with family history of alcoholism contributes to the understanding of pre-existing brain structural conditions and characterization of cognition and attention processes in high-risk individuals. Attention and cognition interact with other brain functions, including perceptual selection, salience, emotion, reward, and memory, through interconnected neural networks. Recent research reports compromised microstructural and functional network connectivity in alcoholism, which can have an effect on the dynamic tuning between brain systems, e.g., the frontally based executive control system, the limbic emotion system, and the midbrain-striatal reward system, thereby impeding cognitive flexibility and behavioral adaptation to changing environments. Finally, we introduce concepts of functional compensation, the capacity to generate attentional resources for performance enhancement, and brain structure recovery with abstinence. An understanding of the neural mechanisms of attention, emotion, and cognition will likely provide the basis for better treatment strategies for developing skills that enhance alcoholism therapy adherence and quality of life, and reduce the propensity for relapse. © 2014 Elsevier B.V. All rights reserved.

  18. Attention deficits and divorce.

    Science.gov (United States)

    Bouchard, Geneviève; Saint-Aubin, Jean

    2014-09-01

    Building on previous work on the role of attention deficits associated with the regulation of executive control in psychiatric disorders, we examine whether these attention deficits are related to an interpersonal disturbance, the experience of divorce. Attentional capacities of 95 randomly selected couples from the general population were measured with a well-established task, the Attentional Network Task, which assesses the efficiency of 3 attention networks (that is, alerting, orienting, and executive control). Among the 190 participants, 32 had experienced a divorce in the past. ANCOVAs were used to compare divorced people in marital or cohabiting unions with people in first unions in their performance on this purely cognitive task. Our findings indicate that divorced people who are currently living in a cohabiting relationship show significantly lower executive control than other adults living as couples, after controlling for sex, age, income, and education. This subgroup of divorced people not only exhibit greater difficulty in responding to some stimuli while ignoring irrelevant ones but also manifest cognitive deficits in conflict resolution. This study highlights the links between attention and the long-term maintenance of intimate relationships. Our results may have important implications for the identification of people at risk for divorce.

  19. Benefits of Sleep Extension on Sustained Attention and Sleep Pressure Before and During Total Sleep Deprivation and Recovery.

    Science.gov (United States)

    Arnal, Pierrick J; Sauvet, Fabien; Leger, Damien; van Beers, Pascal; Bayon, Virginie; Bougard, Clément; Rabat, Arnaud; Millet, Guillaume Y; Chennaoui, Mounir

    2015-12-01

    To investigate the effects of 6 nights of sleep extension on sustained attention and sleep pressure before and during total sleep deprivation and after a subsequent recovery sleep. Subjects participated in two experimental conditions (randomized cross-over design): extended sleep (EXT, 9.8 ± 0.1 h (mean ± SE) time in bed) and habitual sleep (HAB, 8.2 ± 0.1 h time in bed). In each condition, subjects performed two consecutive phases: (1) 6 nights of either EXT or HAB (2) three days in-laboratory: baseline, total sleep deprivation and after 10 h of recovery sleep. Residential sleep extension and sleep performance laboratory (continuous polysomnographic recording). 14 healthy men (age range: 26-37 years). EXT vs. HAB sleep durations prior to total sleep deprivation. Total sleep time and duration of all sleep stages during the 6 nights were significantly higher in EXT than HAB. EXT improved psychomotor vigilance task performance (PVT, both fewer lapses and faster speed) and reduced sleep pressure as evidenced by longer multiple sleep latencies (MSLT) at baseline compared to HAB. EXT limited PVT lapses and the number of involuntary microsleeps during total sleep deprivation. Differences in PVT lapses and speed and MSLT at baseline were maintained after one night of recovery sleep. Six nights of extended sleep improve sustained attention and reduce sleep pressure. Sleep extension also protects against psychomotor vigilance task lapses and microsleep degradation during total sleep deprivation. These beneficial effects persist after one night of recovery sleep. © 2015 Associated Professional Sleep Societies, LLC.

  20. Connectivity supporting attention in children with attention deficit hyperactivity disorder

    Directory of Open Access Journals (Sweden)

    Anita D. Barber

    2015-01-01

    While CON–DMN anti-correlation is associated with improved attention in ADHD, other circuitry supports improved attention in TD children. Greater CON–DMN anti-correlation supported better attentional control in children with ADHD, but worse attentional control in TD children. On the other hand, greater DMN–occipital anti-correlation supported better attentional control in TD children.

  1. Time-lapse electrical resistivity tomography: a powerful tool for landslide monitoring?

    Science.gov (United States)

    Perrone, A.

    2011-12-01

    The extreme rainfall events and the quick snowmelt occurrences play an important role in the triggering of the landslides. The occurrence of one of these factors can determine the variation of water content in the first layers of the subsoil and as a consequence a quick soil saturation inducing both an increase in pore-water pressures and the overloaded of the slopes progressively collapsing. The electrical resistivity, self-potential, electromagnetic induction and GPR methods can be considered as the most appropriate for assessing the presence of water in the underground. Such methods allow us to study the behavior of water content over much wider and deeper areas than those offered by traditional methods (thermo-gravimetric, tensiometric, TDR, etc) based on spot measures and concerning small volumes. In particular, the Electrical Resistivity Tomography (ERT), which has already proved to be a powerful tool both for the geometrical reconstruction of a landslide body (location of sliding surface, estimation of the thickness of the slide material) and the individuation of high water content areas, can be considered as an alternative tool to be employed for a qualitative and quantitative water content monitoring in the first layers of the subsoil. Indeed, time-lapse 2D ERT can be tested in order to gather information on the temporal and spatial patterns of water infiltration processes and water content variation. This work reports the preliminary results from a new prototype system planned to obtain time-lapse 2D ERTs, TDR and precipitation measurements in two landslide areas located in the Southern Apennine chain (Italy). The system was planned with the aim to estimate the variation of the resistivity parameter on a long period considering the water content variation, the rain water infiltration and the seasonal changes. The prototype system, linked to a pc used for storing data and managing the time interval acquisition, consists of: a resistivimeter connected to a

  2. Attention and reading skills.

    Science.gov (United States)

    Commodari, Elena; Guarnera, Maria

    2005-04-01

    Attention plays a critical role in information processing. Its adequate functioning is required for correct development of complex cognitive abilities and regular scholastic progress. Children with attention deficits often have difficulties in reading, writing, and arithmetic. The present study investigated interactions among reading skills, overall scholastic performance as rated by teachers, and components of attention: visual reaction time, simple immediate span of attention, and selectivity. The sample was 98 students in the first and second years of public junior high school (age range 11-14 years, M = 12.6, SD = 1.2), i.e., with expected already well-established reading. Reading was evaluated using Comprehension, Accuracy, and Speed tests. Overall scholastic performance was obtained by means of teachers' ratings. Simple Reaction Time, Digit Span, and Color-Word Interference, included in a multitask computerized test, assessed attention. Analysis confirmed the hypothesis that the reading skills are strongly predictive of the Scholastic Assessment rated by the teachers. High scholastic ratings were correlated with Reading Speed and Accuracy rather than Reading Comprehension. Poor readers showed worse performances on the Digit Span test which measures simple immediate span of attention. Good and poor readers obtained a similar score on the Color-Word Interference task. This observation seems to contrast with the more common interpretation of this effect, suggesting that reading is an automatic process and, therefore, the semantic dimension overcomes the controlled perceptual one. According to other studies, an alternative explanation is suggested. In conclusion, present results confirm the hypothesis of a strong link among reading speed and accuracy, scholastic assessment as rated by teachers, simple immediate span of attention, and visual reaction time.

  3. Alcohol and Sleep Restriction Combined Reduces Vigilant Attention, Whereas Sleep Restriction Alone Enhances Distractibility

    Science.gov (United States)

    Lee, James; Manousakis, Jessica; Fielding, Joanne; Anderson, Clare

    2015-01-01

    Study Objectives: Alcohol and sleep loss are leading causes of motor vehicle crashes, whereby attention failure is a core causal factor. Despite a plethora of data describing the effect of alcohol and sleep loss on vigilant attention, little is known about their effect on voluntary and involuntary visual attention processes. Design: Repeated-measures, counterbalanced design. Setting: Controlled laboratory setting. Participants: Sixteen young (18–27 y; M = 21.90 ± 0.60 y) healthy males. Interventions: Participants completed an attention test battery during the afternoon (13:00–14:00) under four counterbalanced conditions: (1) baseline; (2) alcohol (0.05% breath alcohol concentration); (3) sleep restriction (02:00–07:00); and (4) alcohol/sleep restriction combined. This test battery included a Psychomotor Vigilance Task (PVT) as a measure of vigilant attention, and two ocular motor tasks—visually guided and antisaccade—to measure the involuntary and voluntary allocation of visual attention. Measurements and Results: Only the combined condition led to reductions in vigilant attention characterized by slower mean reaction time, fastest 10% responses, and increased number of lapses (P Sleep restriction alone however increased both antisaccade inhibitory errors [45.8% errors versus 185.0 msec all others) to a peripheral target (P sleep restriction combined reduces vigilant attention, whereas sleep restriction alone enhances distractibility. SLEEP 2015;38(5):765–775. PMID:25515101

  4. In-situ, time-lapse study of extracellular polymeric substance discharge in Streptococcus mutans biofilm.

    Science.gov (United States)

    Liu, Bernard Haochih; Yu, Li-Chieh

    2017-02-01

    Streptococcus mutans is one of the main pathogens that cause tooth decay. By metabolizing carbohydrates, S. mutans emits extracellular polymeric substance (EPS) that adheres to the tooth surface and forms layers of biofilm. Periodontal disease occurs due to the low pH environment created by S. mutans biofilm, and such an acidic environment gradually erodes tooth enamel. Since the existence of EPS is essential in the formation of biofilm, the in-situ investigation of its generation and distribution in real time is the key to the control and suppression of S. mutans biofilm. Prior studies of the biofilm formation process by fluorescence microscope, scanning electron microscope, or spectroscope have roughly divided the mechanism into three stages: (1) initial attachment; (2) microcolonies; and (3) maturation. However, these analytical methods are incapable to observe real-time changes in different locations of the extracellular matrix, and to analyze mechanical properties for single bacteria in micro and nanoscale. Since atomic force microscopy (AFM) operates by precise control of tip-sample interaction forces in liquid and in air, living microorganisms can be analyzed under near-physiological conditions. Thus, analytical techniques based on AFM constitute powerful tools for the study of biological samples, both qualitatively and quantitatively. In this study, we used AFM to quantitatively track the changes of multiple nanomechanical properties of S. mutans, including dissipation energy, adhesion force, deformation, and elastic modulus at different metabolic stages. The data revealed that the bacterial extracellular matrix has a gradient distribution in stickiness, in which different stickiness indicates the variation of EPS compositions, freshness, and metabolic stages. In-situ, time-lapse AFM images showed the local generation and distribution of EPS at different times, in which the highest adhesion distributed along sides of the S. mutans cells. Through time-lapse

  5. Modelling auditory attention.

    Science.gov (United States)

    Kaya, Emine Merve; Elhilali, Mounya

    2017-02-19

    Sounds in everyday life seldom appear in isolation. Both humans and machines are constantly flooded with a cacophony of sounds that need to be sorted through and scoured for relevant information-a phenomenon referred to as the 'cocktail party problem'. A key component in parsing acoustic scenes is the role of attention, which mediates perception and behaviour by focusing both sensory and cognitive resources on pertinent information in the stimulus space. The current article provides a review of modelling studies of auditory attention. The review highlights how the term attention refers to a multitude of behavioural and cognitive processes that can shape sensory processing. Attention can be modulated by 'bottom-up' sensory-driven factors, as well as 'top-down' task-specific goals, expectations and learned schemas. Essentially, it acts as a selection process or processes that focus both sensory and cognitive resources on the most relevant events in the soundscape; with relevance being dictated by the stimulus itself (e.g. a loud explosion) or by a task at hand (e.g. listen to announcements in a busy airport). Recent computational models of auditory attention provide key insights into its role in facilitating perception in cluttered auditory scenes.This article is part of the themed issue 'Auditory and visual scene analysis'. © 2017 The Authors.

  6. Cognitive Penetration and Attention

    Science.gov (United States)

    Gross, Steven

    2017-01-01

    Zenon Pylyshyn argues that cognitively driven attentional effects do not amount to cognitive penetration of early vision because such effects occur either before or after early vision. Critics object that in fact such effects occur at all levels of perceptual processing. We argue that Pylyshyn’s claim is correct—but not for the reason he emphasizes. Even if his critics are correct that attentional effects are not external to early vision, these effects do not satisfy Pylyshyn’s requirements that the effects be direct and exhibit semantic coherence. In addition, we distinguish our defense from those found in recent work by Raftopoulos and by Firestone and Scholl, argue that attention should not be assimilated to expectation, and discuss alternative characterizations of cognitive penetrability, advocating a kind of pluralism. PMID:28275358

  7. Attention in Urban Foraging

    Directory of Open Access Journals (Sweden)

    Malcolm McCullough

    2013-05-01

    Full Text Available This position paper argues how there has to be much more to smart city learning than just wayshowing, and something better as augmented reality than covering the world with instructions. Attention has become something for many people to know better in an age of information superabundance. Embodied cognition explains how the work-ings of attention are not solely a foreground task, as if attention is something to pay. As digital media appear in ever more formats and contexts, their hybrids with physical form increasing influence how habitual engagement with persistent situations creates learning. Ambient information can just add to the distraction by multitasking, or it can support more favorable processes of shifting among different kinds of information with a particular intent. As one word for this latter process, foraging deserves more consideration in smart city learning

  8. Attention: an evolving construct.

    Science.gov (United States)

    Joyce, Arthur; Hrin, Skip

    2015-01-01

    We review the implications of large-scale brain systems on the construct of attention by first focusing on significant theories and discoveries during the previous 150 years and then considering how the comparatively recent discovery of large-scale brain systems may render previous conceptualizations of attention outdated. Seven functional brain networks are briefly reviewed and the implications of emerging principles of brain functioning for test construction and neuropsychological evaluation are considered. To remain a relevant discipline moving into the 21st century, the field of neuropsychology needs to apply the principles that have been discovered about brain networks to better inform our understanding of attention as well as our ever-refining evaluation of this construct.

  9. Visual attention capacity

    DEFF Research Database (Denmark)

    Habekost, Thomas; Starrfelt, Randi

    2009-01-01

    Psychophysical studies have identified two distinct limitations of visual attention capacity: processing speed and apprehension span. Using a simple test, these cognitive factors can be analyzed by Bundesen's Theory of Visual Attention (TVA). The method has strong specificity and sensitivity...... to patient testing, and review existing TVA-based patient studies organized by lesion anatomy. Lesions in three anatomical regions affect visual capacity: The parietal lobes, frontal cortex and basal ganglia, and extrastriate cortex. Visual capacity thus depends on large, bilaterally distributed anatomical...... networks that include several regions outside the visual system. The two visual capacity parameters are functionally separable, but seem to rely on largely overlapping brain areas....

  10. Live time-lapse dataset of in vitro wound healing experiments.

    Science.gov (United States)

    Zaritsky, Assaf; Natan, Sari; Kaplan, Doron; Ben-Jacob, Eshel; Tsarfaty, Ilan

    2015-01-01

    The wound healing assay is the common method to study collective cell migration in vitro. Computational analyses of live imaging exploit the rich temporal information and significantly improve understanding of complex phenomena that emerge during this mode of collective motility. Publicly available experimental data can allow application of new analyses to promote new discoveries, and assess algorithms' capabilities to distinguish between different experimental conditions. A freely-available dataset of 31 time-lapse in vitro wound healing experiments of two cell lines is presented. It consists of six different experimental conditions with 4-6 replicates each, gathered to study the effects of a growth factor on collective cell migration. The raw data is available at 'The Cell: an Image Library' repository. This Data Note provides detailed description of the data, intermediately processed data, scripts and experimental validations that have not been reported before and are currently available at GigaDB. This is the first publicly available repository of live collective cell migration data that includes independent replicates for each set of conditions. This dataset has the potential for extensive reuse. Some aspects in the data remain unexplored and can be exploited extensively to reveal new insight. The dataset could also be used to assess the performance of available and new quantification methods by demonstrating phenotypic discriminatory capabilities between the different experimental conditions. It may allow faster and more elaborated, reproducible and effective analyses, which will likely lead to new biological and biophysical discoveries.

  11. Time-lapse analysis of potential cellular responsiveness to Johrei, a Japanese healing technique

    Directory of Open Access Journals (Sweden)

    Moore Dan

    2005-01-01

    Full Text Available Abstract Background Johrei is an alternative healing practice which involves the channeling of a purported universal healing energy to influence the health of another person. Despite little evidence to support the efficacy of such practices the use of such treatments is on the rise. Methods We assessed cultured human cancer cells for potential responsiveness to Johrei treatment from a short distance. Johrei treatment was delivered by practitioners who participated in teams of two, alternating every half hour for a total of four hours of treatment. The practitioners followed a defined set of mental procedures to minimize variability in mental states between experiments. An environmental chamber maintained optimal growth conditions for cells throughout the experiments. Computerized time-lapse microscopy allowed documentation of cancer cell proliferation and cell death before, during and after Johrei treatments. Results Comparing eight control experiments with eight Johrei intervention experiments, we found no evidence of a reproducible cellular response to Johrei treatment. Conclusion Cell death and proliferation rates of cultured human cancer cells do not appear responsive to Johrei treatment from a short distance.

  12. Exploring reflective 'critical incident' documentation of professionalism lapses in a medical undergraduate setting

    Directory of Open Access Journals (Sweden)

    McLachlan John C

    2009-07-01

    Full Text Available Abstract Background Measuring professionalism in undergraduate medical students is a difficult process, and no one method has currently emerged as the definitive means of assessment in this field. Student skills in reflection have been shown to be highly important in the development of professional behaviours. By studying student reflections on lapses in professional judgement, recorded as 'critical incidents', it is possible to explore themes which are significant for the development of professional behaviour in an undergraduate setting. Methods We examined critical incident reporting combined with optional written student reflection as a method for exploring professionalism in undergraduate medical students. 228 students split between Year 1 and 2 of one academic year of undergraduate medicine were studied retrospectively and a grounded theory approach to analysis was employed. Results This year generated 16 critical incident reports and corresponding student reflections, all of which were considered. In addition to identifying the nature of the critical incidents, 3 principal themes emerged. These were the impact and consequences of the report having been made, student reactions to the events (both positive and negative, and student responses regarding future actions. Conclusion This study indicates that unprofessional behaviour can be identified and challenged by both the faculty and the students involved, and suggests that positive behavioural changes might be made with the aim of preventing future occurrences. We provide a low cost approach of measuring and recording professional behaviour.

  13. Untangling cell tracks: Quantifying cell migration by time lapse image data analysis.

    Science.gov (United States)

    Svensson, Carl-Magnus; Medyukhina, Anna; Belyaev, Ivan; Al-Zaben, Naim; Figge, Marc Thilo

    2017-10-04

    Automated microscopy has given researchers access to great amounts of live cell imaging data from in vitro and in vivo experiments. Much focus has been put on extracting cell tracks from such data using a plethora of segmentation and tracking algorithms, but further analysis is normally required to draw biologically relevant conclusions. Such relevant conclusions may be whether the migration is directed or not, whether the population has homogeneous or heterogeneous migration patterns. This review focuses on the analysis of cell migration data that are extracted from time lapse images. We discuss a range of measures and models used to analyze cell tracks independent of the biological system or the way the tracks were obtained. For single-cell migration, we focus on measures and models giving examples of biological systems where they have been applied, for example, migration of bacteria, fibroblasts, and immune cells. For collective migration, we describe the model systems wound healing, neural crest migration, and Drosophila gastrulation and discuss methods for cell migration within these systems. We also discuss the role of the extracellular matrix and subsequent differences between track analysis in vitro and in vivo. Besides methods and measures, we are putting special focus on the need for openly available data and code, as well as a lack of common vocabulary in cell track analysis. © 2017 International Society for Advancement of Cytometry. © 2017 International Society for Advancement of Cytometry.

  14. Could monopronucleated ICSI zygotes be considered for transfer? Analysis through time-lapse monitoring and PGS.

    Science.gov (United States)

    Mateo, S; Vidal, F; Parriego, M; Rodríguez, I; Montalvo, V; Veiga, A; Boada, M

    2017-07-01

    The purpose of this study was to investigate the chromosomal constitution and the developmental potential of intracytoplasmic sperm injection (ICSI) deriving embryos displaying a single pronucleus at the zygote stage. Eighty-eight embryos from single pronucleus (1PN) two polar bodies (2PB) ICSI zygotes from 64 preimplantational genetic screening (PGS) cycles (October 2012-December 2014), were retrospectively analyzed. Zygotes were cultured in a time-lapse incubator. Embryo biopsy was performed on day 3 and genetic analysis approached by array comparative genomic hybridization. Chromosomal analysis revealed that 17% (15/88) of embryos derived from 1PN 2PB zygotes were diagnosed as euploid. After blastomere biopsy at day 3, the blastocyst rate at day 5 was 3.4% (3/88). Only 2.3% (2/88) euploid blastocysts were obtained. In two couples and after counseling and patient agreement, the transfer of a euploid blastocyst from a 1PN 2PB ICSI zygote was performed resulting in the birth of a healthy child. These results open the possibility to consider embryos coming from 1PN 2PB ICSI zygotes for transfer when no other embryos from 2PN 2PB ICSI zygotes are available and if a PGS diagnosis of euploidy is obtained. Confirmation of biparental inheritance is strongly recommended.

  15. A time-lapse photography method for monitoring salmon (Oncorhynchus spp. passage and abundance in streams

    Directory of Open Access Journals (Sweden)

    William W. Deacy

    2016-06-01

    Full Text Available Accurately estimating population sizes is often a critical component of fisheries research and management. Although there is a growing appreciation of the importance of small-scale salmon population dynamics to the stability of salmon stock-complexes, our understanding of these populations is constrained by a lack of efficient and cost-effective monitoring tools for streams. Weirs are expensive, labor intensive, and can disrupt natural fish movements. While conventional video systems avoid some of these shortcomings, they are expensive and require excessive amounts of labor to review footage for data collection. Here, we present a novel method for quantifying salmon in small streams (<15 m wide, <1 m deep that uses both time-lapse photography and video in a model-based double sampling scheme. This method produces an escapement estimate nearly as accurate as a video-only approach, but with substantially less labor, money, and effort. It requires servicing only every 14 days, detects salmon 24 h/day, is inexpensive, and produces escapement estimates with confidence intervals. In addition to escapement estimation, we present a method for estimating in-stream salmon abundance across time, data needed by researchers interested in predator--prey interactions or nutrient subsidies. We combined daily salmon passage estimates with stream specific estimates of daily mortality developed using previously published data. To demonstrate proof of concept for these methods, we present results from two streams in southwest Kodiak Island, Alaska in which high densities of sockeye salmon spawn.

  16. Time-Lapse Dynamics of the Mouse Oocyte Chromatin Organisation during Meiotic Resumption

    Directory of Open Access Journals (Sweden)

    Martina Belli

    2014-01-01

    Full Text Available In the mammalian oocyte, distinct patterns of centromeres and pericentromeric heterochromatin localisation correlate with the gamete’s developmental competence. Mouse antral oocytes display two main types of chromatin organisation: SN oocytes, with a ring of Hoechst-positive chromatin surrounding the nucleolus, and NSN oocytes lacking this ring. When matured to MII and fertilised, only SN oocytes develop beyond the 2-cell, and reach full term. To give detailed information on the dynamics of the SN or NSN chromatin during meiosis resumption, we performed a 9 hr time-lapse observation. The main significant differences recorded are: (1 reduction of the nuclear area only in SN oocytes; (2 ~17 min delay of GVBD in NSN oocytes; (3 chromatin condensation, after GVBD, in SN oocytes; (4 formation of 4-5 CHCs in SN oocytes; (5 increase of the perivitelline space, ~57 min later in NSN oocytes; (6 formation of a rosette-like disposition of CHCs, ~84 min later in SN oocytes; (7 appearance of the MI plate ~40 min later in NSN oocytes. Overall, we described a pathway of transition from the GV to the MII stage that is punctuated of discrete recordable events showing their specificity and occurring with different time kinetics in the two types of oocytes.

  17. Thermal erosion of a permafrost coastline: Improving process-based models using time-lapse photography

    Science.gov (United States)

    Wobus, C.; Anderson, R.; Overeem, I.; Matell, N.; Clow, G.; Urban, F.

    2011-01-01

    Coastal erosion rates locally exceeding 30 m y-1 have been documented along Alaska's Beaufort Sea coastline, and a number of studies suggest that these erosion rates have accelerated as a result of climate change. However, a lack of direct observational evidence has limited our progress in quantifying the specific processes that connect climate change to coastal erosion rates in the Arctic. In particular, while longer ice-free periods are likely to lead to both warmer surface waters and longer fetch, the relative roles of thermal and mechanical (wave) erosion in driving coastal retreat have not been comprehensively quantified. We focus on a permafrost coastline in the northern National Petroleum Reserve-Alaska (NPR-A), where coastal erosion rates have averaged 10-15 m y-1 over two years of direct monitoring. We take advantage of these extraordinary rates of coastal erosion to observe and quantify coastal erosion directly via time-lapse photography in combination with meteorological observations. Our observations indicate that the erosion of these bluffs is largely thermally driven, but that surface winds play a crucial role in exposing the frozen bluffs to the radiatively warmed seawater that drives melting of interstitial ice. To first order, erosion in this setting can be modeled using formulations developed to describe iceberg deterioration in the open ocean. These simple models provide a conceptual framework for evaluating how climate-induced changes in thermal and wave energy might influence future erosion rates in this setting.

  18. Time-lapse imaging provides further evidence that planar arrangement of blastomeres is highly abnormal.

    Science.gov (United States)

    Ebner, Thomas; Höggerl, Alexandra; Oppelt, Peter; Radler, Elisabeth; Enzelsberger, Simon-Hermann; Mayer, Richard B; Petek, Erwin; Shebl, Omar

    2017-12-01

    Recently, guidelines on the annotation of dynamic human embryo monitoring recommended screening for the presence of planar blastomere arrangement at the 4-cell stage. This observational study was set up in order to analyze whether developmental kinetics of planar human embryos are different from tetrahedral ones. Therefore, embryos of 115 consecutive ICSI patients (showing 32 planar and 554 tetrahedral embryos) were cultured in a new time-lapse system (Miri TL) and their embryos were annotated for morphokinetic development and screened for irregular cleavages and morphological dysmorphisms. Significantly less planar embryos reached blastocyst stage and showed worse quality as compared to regular tetrahedral embryos. The rate of bi- and/or multinucleation was also significantly higher in the affected group. Irregular cleavages, particularly embryo rolling, were more often seen in planar embryos. Morphokinetics between planar and tetrahedral were distinguishable up to 4-cell stage (t2-t4), thereafter the observed delay in planar embryos (t8) was more likely the result of a higher rate of arrested embryos in the planar group. Planar embryos are associated with both a significant increase in irregular cleavage as well as a delay in preimplantation development. This indicates that planar embryos are rather abnormal and should only be considered for transfer if no other embryos are available.

  19. Agency, lapse in condom use and relationship intimacy among female sex workers in Jamaica.

    Science.gov (United States)

    Bailey, Althea E; Figueroa, John Peter

    2017-09-01

    This paper explores barriers to consistent condom use among female sex workers in Jamaica in a qualitative study using grounded theory. Multiple perspectives were sought through 44 in-depth interviews conducted with female sex workers, clients, the partners of sex workers and facilitators of sex work. Poverty and lack of education or skills, severely limited support systems as well as childhood abuse served to push the majority of participants into sex work and created vulnerability to HIV and other STIs. Despite these constraints, women found ways to exercise agency, ensure condom use, adopt protective measures and gain economic advantage in various aspects of the Jamaican sex trade. Perceived relationship intimacy between sex workers and their clients and/or their main partners emerged as the main factor contributing to reduced risk perception and inconsistent condom use. Relationship intimacy, with associated trust and affirmation of self, is the most important factor influencing sexual decision-making with respect to lapse in condom use among female sex workers in Jamaica. Study findings provide important insights that can enhance individual psychosocial, interpersonal and community-based interventions as well as inform environmental, structural and policy interventions to reduce risk and vulnerability among female sex workers.

  20. ESIAC: A data products system for ERTS imagery (time-lapse viewing and measuring)

    Science.gov (United States)

    Evans, W. E.; Serebreny, S. M.

    1974-01-01

    An Electronic Satellite Image Analysis Console (ESIAC) has been developed for visual analysis and objective measurement of earth resources imagery. The system is being employed to process imagery for use by USGS investigators in several different disciplines studying dynamic hydrologic conditions. The ESIAC provides facilities for storing registered image sequences in a magnetic video disc memory for subsequent recall, enhancement, and animated display in monochrome or color. The unique feature of the system is the capability to time-lapse the ERTS imagery and/or analytic displays of the imagery. Data products have included quantitative measurements of distances and areas, brightness profiles, and movie loops of selected themes. The applications of these data products are identified and include such diverse problem areas as measurement of snowfield extent, sediment plumes from estuary dicharge, playa inventory, phreatophyte and other vegetation changes. A comparative ranking of the electronic system in terms of accuracy, cost effectiveness and data output shows it to be a viable means of data analysis.

  1. Time-lapse resistivity analysis of Quaternary sediments in the Midlands of Ireland

    Science.gov (United States)

    Pellicer, Xavier M.; Zarroca, Mario; Gibson, Paul

    2012-07-01

    Electrical Resistivity Tomography (ERT) data are influenced by a number of factors associated with the subsurface such as porosity, moisture content and lithology; as well as external factors such as rainfall and temperature. Two time-lapse ERT profiles with 5 m and two with 2 m electrode spacings were acquired over a range of Quaternary sediment types encompassing till, esker gravel, glaciofluvial sand and silt and glaciolacustrine silt/clay. Data were collected on a monthly basis during 2006 at a site located in the Midlands of Ireland in order to evaluate the influence of such conditioning factors on the resistivity of the subsurface. Effective recharge, the depth of investigation, the texture and the internal architecture of the different sediment types and temperature variation are the main factors influencing the resistivity seasonal variation. The shallow subsurface (factors influencing the electrical response of the subsurface are the electrode spacing used for data collection and the seasonal temperature variation of the subsurface. Two methods for temperature correction of electrical resistivity data were tested in this study — both gave similar results. Resistivity values recorded in the shallow subsurface (< 5 m) show variations of over 15% subsequent to temperature correction. The results illustrate that seasonal temperature changes and their influence on subsurface temperature have to be accounted for in data interpretation and emphasise the potential of this technique for the estimation of the rate of movement of the wetting/drying front in soft sediments.

  2. Adaptive time-lapse optimized survey design for electrical resistivity tomography monitoring

    Science.gov (United States)

    Wilkinson, Paul B.; Uhlemann, Sebastian; Meldrum, Philip I.; Chambers, Jonathan E.; Carrière, Simon; Oxby, Lucy S.; Loke, M. H.

    2015-10-01

    Adaptive optimal experimental design methods use previous data and results to guide the choice and design of future experiments. This paper describes the formulation of an adaptive survey design technique to produce optimal resistivity imaging surveys for time-lapse geoelectrical monitoring experiments. These survey designs are time-dependent and, compared to dipole-dipole or static optimized surveys that do not change over time, focus a greater degree of the image resolution on regions of the subsurface that are actively changing. The adaptive optimization method is validated using a controlled laboratory monitoring experiment comprising a well-defined cylindrical target moving along a trajectory that changes its depth and lateral position. The algorithm is implemented on a standard PC in conjunction with a modified automated multichannel resistivity imaging system. Data acquisition using the adaptive survey designs requires no more time or power than with comparable standard surveys, and the algorithm processing takes place while the system batteries recharge. The results show that adaptively designed optimal surveys yield a quantitative increase in image quality over and above that produced by using standard dipole-dipole or static (time-independent) optimized surveys.

  3. A clustering approach applied to time-lapse ERT interpretation - Case study of Lascaux cave

    Science.gov (United States)

    Xu, Shan; Sirieix, Colette; Riss, Joëlle; Malaurent, Philippe

    2017-09-01

    The Lascaux cave, located in southwest France, is one of the most important prehistoric cave in the world that shows Paleolithic paintings. This study aims to characterize the structure of the weathered epikarst setting located above the cave using Time-Lapse Electrical Resistivity Tomography (ERT) combined with local hydrogeological and climatic environmental data. Twenty ERT profiles were carried out for two years and helped us to record the seasonal and spatial variations of the electrical resistivity of the hydraulic upstream area of the Lascaux cave. The 20 interpreted resistivity models were merged into a single synthetic model using a multidimensional statistical method (Hierarchical Agglomerative Clustering). The individual blocks from the synthetic model associated with a similar resistivity variability were gathered into 7 clusters. We combined the resistivity temporal variations with climatic and hydrogeological data to propose a geo-electrical model that relates to a conceptual geological model. We provide a geological interpretation for each cluster regarding epikarst features. The superficial clusters (no 1 & 2) are linked to effective rainfall and trees, probably a fractured limestone. Another two clusters (no 6 & 7) are linked to detrital formations (sand and clay respectively). The cluster 3 may correspond to a marly limestone that forms a non-permeable horizon. Finally, the electrical behavior of the last two clusters (no 4 & 5) is correlated with the variation of flow rate; they may be a privileged feed zone of the flow in the cave.

  4. Time-lapse Imaging of Primary Preneoplastic Mammary Epithelial Cells Derived from Genetically Engineered Mouse Models of Breast Cancer

    OpenAIRE

    Nakles, Rebecca E.; Millman, Sarah L.; Cabrera, M. Carla; Johnson, Peter; Mueller, Susette; Hoppe, Philipp S.; Schroeder, Timm; Furth, Priscilla A.

    2013-01-01

    Time-lapse imaging can be used to compare behavior of cultured primary preneoplastic mammary epithelial cells derived from different genetically engineered mouse models of breast cancer. For example, time between cell divisions (cell lifetimes), apoptotic cell numbers, evolution of morphological changes, and mechanism of colony formation can be quantified and compared in cells carrying specific genetic lesions. Primary mammary epithelial cell cultures are generated from mammary glands without...

  5. Conservatism predicts lapses from vegetarian/vegan diets to meat consumption (through lower social justice concerns and social support).

    Science.gov (United States)

    Hodson, Gordon; Earle, Megan

    2018-01-01

    Lapses from vegetarian and vegan (i.e., veg*n) food choices to meat consumption are very common, suggesting that sustaining veg*nism is challenging. But little is known about why people return to eating animals after initially deciding to avoid meat consumption. Several potential explanatory factors include personal inconvenience, meat cravings, awkwardness in social settings, or health/nutrition concerns. Here we test the degree to which political ideology predicts lapsing to meat consumption. Past research demonstrates that political ideology predicts present levels of meat consumption, whereby those higher in right-wing ideologies eat more animals, even after controlling for their hedonistic liking of meat (e.g., Dhont & Hodson, 2014). To what extent might political ideology predict whether one has lapsed from veg*n foods back to meat consumption? In a largely representative US community sample (N = 1313) of current and former veg*ns, those higher (vs. lower) in conservatism exhibited significantly greater odds of being a former than current veg*n, even after controlling for age, education, and gender. This ideology-lapsing relation was mediated (i.e., explained) by those higher (vs. lower) in conservatism: (a) adopting a veg*n diet for reasons less centered in justice concerns (animal rights, environment, feeding the poor); and (b) feeling socially unsupported in their endeavor. In contrast, factors such as differential meat craving or lifestyle inconvenience played little mediational role. These findings demonstrate that ideology and justice concerns are particularly relevant to understanding resilience in maintaining veg*n food choices. Implications for understanding why people eat meat, and how to develop intervention strategies, are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Time-lapse three-dimensional inversion of complex conductivity data using an active time constrained (ATC) approach

    Science.gov (United States)

    Karaoulis, M.; Revil, A.; Werkema, D.D.; Minsley, B.J.; Woodruff, W.F.; Kemna, A.

    2011-01-01

    Induced polarization (more precisely the magnitude and phase of impedance of the subsurface) is measured using a network of electrodes located at the ground surface or in boreholes. This method yields important information related to the distribution of permeability and contaminants in the shallow subsurface. We propose a new time-lapse 3-D modelling and inversion algorithm to image the evolution of complex conductivity over time. We discretize the subsurface using hexahedron cells. Each cell is assigned a complex resistivity or conductivity value. Using the finite-element approach, we model the in-phase and out-of-phase (quadrature) electrical potentials on the 3-D grid, which are then transformed into apparent complex resistivity. Inhomogeneous Dirichlet boundary conditions are used at the boundary of the domain. The calculation of the Jacobian matrix is based on the principles of reciprocity. The goal of time-lapse inversion is to determine the change in the complex resistivity of each cell of the spatial grid as a function of time. Each model along the time axis is called a 'reference space model'. This approach can be simplified into an inverse problem looking for the optimum of several reference space models using the approximation that the material properties vary linearly in time between two subsequent reference models. Regularizations in both space domain and time domain reduce inversion artefacts and improve the stability of the inversion problem. In addition, the use of the time-lapse equations allows the simultaneous inversion of data obtained at different times in just one inversion step (4-D inversion). The advantages of this new inversion algorithm are demonstrated on synthetic time-lapse data resulting from the simulation of a salt tracer test in a heterogeneous random material described by an anisotropic semi-variogram. ?? 2011 The Authors Geophysical Journal International ?? 2011 RAS.

  7. Impact of Twitter intensity, time, and location on message lapse of bluebird's pursuit of fleas in Madagascar.

    Science.gov (United States)

    Da'ar, Omar B; Yunus, Faisel; Md Hossain, Nassif; Househ, Mowafa

    The recent outbreak of bubonic plague in Madagascar reminds us of the continuing public health challenges posed by such deadly diseases in various parts of the world years after their eradication. This study examines the role of Twitter in public health disease surveillance with special focus on how Twitter intensity, time, and location issues explain Twitter plague message delay. We retrospectively analyzed the Twitter feeds of the 2014 bubonic plague outbreak in Madagascar. The analyses are based on the plague-related data available in the public domain between November 19th and 27th 2014. The data were compiled in March 2015. We calculated the time differential between the tweets and retweets, and analyzed various characteristics of the Tweets including Twitter intensity of the users. A total of 6873 Twitter users were included in the study, of which 52% tweeted plague-related information during the morning hours (before mid-day), and 87% of the tweets came from the west of the epicenter of the plague. More importantly, while session of tweet lease and relative location had effect on message lapse, absolute location did not. Additionally, we found no evidence of differential effect of location on message lapse based on relative location i.e. tweets from west or east nor number of following. However, there is evidence that more intense Twitter use appears to have significant effect on message lapse such that as the number of tweets became more intense, time differential between the tweets and retweets increased while higher number of retweets diminished message lapse. This study affirms that Twitter can play an important role in ongoing disease surveillance and the timely dissemination of information during public health emergencies independent of the time and space restrictions. Further ways should be explored to embed social media channels in routine public health practice. Copyright © 2017 King Saud Bin Abdulaziz University for Health Sciences. Published by

  8. Managerial Attention in International SMEs

    NARCIS (Netherlands)

    Fan, Jiasi

    2017-01-01

    Managerial attention affects organizational strategies and the resulting consequences. In the international business context, it is noted that how much attention managers give to the international marketplace, i.e., international attention, has profound implications for large global companies’

  9. A time-series method for automated measurement of changes in mitotic and interphase duration from time-lapse movies.

    Directory of Open Access Journals (Sweden)

    Frederic D Sigoillot

    Full Text Available Automated time-lapse microscopy can visualize proliferation of large numbers of individual cells, enabling accurate measurement of the frequency of cell division and the duration of interphase and mitosis. However, extraction of quantitative information by manual inspection of time-lapse movies is too time-consuming to be useful for analysis of large experiments.Here we present an automated time-series approach that can measure changes in the duration of mitosis and interphase in individual cells expressing fluorescent histone 2B. The approach requires analysis of only 2 features, nuclear area and average intensity. Compared to supervised learning approaches, this method reduces processing time and does not require generation of training data sets. We demonstrate that this method is as sensitive as manual analysis in identifying small changes in interphase or mitotic duration induced by drug or siRNA treatment.This approach should facilitate automated analysis of high-throughput time-lapse data sets to identify small molecules or gene products that influence timing of cell division.

  10. High school versus graduate entry in a Saudi medical school - is there any difference in academic performance and professionalism lapses?

    Science.gov (United States)

    Al Rumayyan, Ahmed Rumayyan; Al Zahrani, Abdulaziz Ahmed; Hameed, Tahir Kamal

    2016-12-19

    King Saud bin Abdulaziz University for Health Sciences (KSAU-HS) was the first university in the Kingdom of Saudi Arabia offering both high school entry and graduate entry (GE) students into medical school. We compared the academic performance and professionalism lapses of high school entry and GE students who undertook the same curriculum and examinations in the College of Medicine, Riyadh, KSAU-HS. Examination scores of 196 high school graduates and 54 GE students over a 4-year period (2010-2014) were used as a measure of academic achievement. For assessment of professionalism lapses, we compared the number of warning letters in both streams of students. In some pre-clinical courses, high school entry students performed significantly better than GE students. There was no significant difference in academic performance of high school entry and GE students in clinical rotations. GE students had a significantly greater number of warning letters per student as compared to high school entry students. This is the first Saudi study to compare the performance of high school entry and GE students in a medical school. Overall, both streams of students performed equally well with high school entry students performing better than GE students in a few pre-clinical courses. We compared professionalism lapses and found an increase in number of warning letters for GE students. More studies are needed to evaluate if there are differences in other assessments of professionalism between these two streams of students.

  11. Phenomenology of Joint Attention

    African Journals Online (AJOL)

    denise

    of phenomenology by offering a phenomenology of joint attention. The first section reviews elementary. Husserlian phenomenology and introduces a system for symbolically representing the structure of intentional mental states. The second section summarizes Edith Stein's phenomenological description of empathy, the ...

  12. Attention, Predation, Counterintuition

    DEFF Research Database (Denmark)

    Clasen, Mathias

    2012-01-01

    of Dracula to account for the novel’s impact and resilience. Dracula connected squarely with late-Victorian anxieties, but the novel also appeals to trans-historical adaptive dispositions. I analyze Stoker’s use of narrative strategies to grab and sustain attention, and Count Dracula as a supercharged...

  13. The Attention Economy

    Directory of Open Access Journals (Sweden)

    Süreyya Çankırı

    2013-11-01

    Full Text Available Understanding the New Currency of Business (originally published by Harvard Business School Press stands out as a new and significant work. The book analyses the psychological dimensions of attention while presenting its key applications in advertising, e­commerce, information management and strategy.

  14. When attention matters: the curious incident of the wandering mind.

    Science.gov (United States)

    Smallwood, Jonathan; McSpadden, Merrill; Schooler, Jonathan W

    2008-09-01

    Attention plays an essential role in the construction of the mental models necessary to make sense of ongoing events. In this article, we consider the implications of temporary inattention during reading for the construction and updating of the situation model during text comprehension. We examined how self-reported mind wandering during reading relates to the online construction of the situation model of the narrative, which in this case involved the pseudonym used by a villain in a detective novella. In successful readers, mind wandering without awareness, referred to as zoning out, was less frequent when the text revealed a clue about the villain's identity. Additional analyses indicated that mind wandering interfered with the construction of the situation model independent of the participants' ability to retrieve factual information. The analysis of the temporal consequences of zoning out indicated that lapses had the greatest influence when they occurred early in the narrative. These results confirm the intuition that zoning out during reading is an indication that the construction of the situation model has gone awry, and underscore the fact that our ability to understand ongoing events depends on the ability to pay attention when it matters.

  15. INVESTOR ATTENTION AND SENTIMENT

    OpenAIRE

    Wang, Jessica Yichun

    2015-01-01

    Investor sentiment and attention are often linked to the same non-economic events making it difficult to understand why and how asset prices are affected. This thesis disentangles these two potential drivers of market behaviour by studying how investors react to sports outcomes, weather conditions and merger and acquisition announcements. Firstly, a new dataset of medals for major participating countries and sponsor firms over four Summer Olympic Games is analysed. Results show...

  16. Overland flow dynamics through visual observation using time-lapse photographs

    Science.gov (United States)

    Silasari, Rasmiaditya; Blöschl, Günter

    2016-04-01

    Overland flow process on agricultural land is important to be investigated as it affects the stream discharge and water quality assessment. During rainfall events the formation of overland flow may happen through different processes (i.e. Hortonian or saturation excess overland flow) based on the governing soil hydraulic parameters (i.e. soil infiltration rate, soil water capacity). The dynamics of the soil water state and the processes will affect the surface runoff response which can be analyzed visually by observing the saturation patterns with a camera. Although visual observation was proven useful in laboratory experiments, the technique is not yet assessed for natural rainfall events. The aim of this work is to explore the use of time-lapse photographs of naturally occurring-saturation patterns in understanding the threshold processes of overland flow generation. The image processing produces orthographic projection of the saturation patterns which will be used to assess the dynamics of overland flow formation in relation with soil moisture state and rainfall magnitude. The camera observation was performed at Hydrological Open Air Laboratory (HOAL) catchment at Petzenkirchen, Lower Austria. The catchment covers an area of 66 ha dominated with agricultural land (87%). The mean annual precipitation and mean annual flow at catchment outlet are 750 mm and 4 l/s, respectively. The camera was set to observe the overland flow along a thalweg on an arable field which was drained in 1950s and has advantages of: (1) representing agricultural land as the dominant part of the catchment, (2) adjacent to the stream with clear visibility (no obstructing objects, such as trees), (3) drained area provides extra cases in understanding the response of tile drain outflow to overland flow formation and vice versa, and (4) in the vicinity of TDT soil moisture stations. The camera takes a picture with 1280 x 720 pixels resolution every minute and sends it directly in a PC via fiber

  17. Attention-Seeking Displays.

    Directory of Open Access Journals (Sweden)

    Szabolcs Számadó

    Full Text Available Animal communication abounds with extravagant displays. These signals are usually interpreted as costly signals of quality. However, there is another important function for these signals: to call the attention of the receiver to the signaller. While there is abundant empirical evidence to show the importance of this stage, it is not yet incorporated into standard signalling theory. Here I investigate a general model of signalling - based on a basic action-response game - that incorporates this searching stage. I show that giving attention-seeking displays and searching for them can be an ESS. This is a very general result and holds regardless whether only the high quality signallers or both high and low types give them. These signals need not be costly at the equilibrium and they need not be honest signals of any quality, as their function is not to signal quality but simply to call the attention of the potential receivers. These kind of displays are probably more common than their current weight in the literature would suggest.

  18. Time lapse inversion of 2D ERT data for monitoring river water infiltration

    Science.gov (United States)

    Wallin, E. L.; Johnson, T. C.; Greenwood, W. J.

    2011-12-01

    Uranium transport in the 300 area is driven by both the chemical and physical effects of stage fluctuations in the Columbia River and resulting river water, ground water interaction. Because river water is less conductive than groundwater, it serves as a natural tracer that can be imaged using surface ERT. We've monitored 4 lines for 4 months over the high stage spring runoff interval to identify preferred flowpaths for river water intrusion. The four lines overlay former waste disposal sites including the processing ponds and sanitary leach trenches. We have used this ERT data set to investigate two methods of time lapse inversion, sequential and all-at-once. Each technique is a model difference approach as opposed to a data difference inversion approach. Both use a regularized inversion with model constraints that regularize spatially and temporally. For the sequential inversion, the starting and reference models are taken from the previous inversion. Both starting and reference models are taken from the first inversion for the all-at-once method. In either case an inversion is triggered if data misfit from the starting model exceeds the chi-squared convergence criteria. It was found that starting with a relatively smooth model provided better visualization of temporal conductivity changes when inverting all data sets with the same initial model, while an initial model exhibiting smaller data misfit may be used successfully as the starting point for sequential inversion. Inland conductivity changes within model cells were found to be highly correlated with river stage, and when paired with the characterization model, provide evidence of waste trenches, the processing pond, as well as the existence of a paleo-channel incised into the Ringold Formation and dipping structures on the Hanford-Ringold contact that provide preferred pathways for river water intrusion.

  19. Time lapse photography as an approach to understanding glide avalanche activity

    Science.gov (United States)

    Hendrikx, Jordy; Peitzsch, Erich H.; Fagre, Daniel B.

    2012-01-01

    Avalanches resulting from glide cracks are notoriously difficult to forecast, but are a recurring problem for numerous avalanche forecasting programs. In some cases glide cracks are observed to open and then melt away in situ. In other cases, they open and then fail catastrophically as large, full-depth avalanches. Our understanding and management of these phenomena are currently limited. It is thought that an increase in the rate of snow gliding occurs prior to full-depth avalanche activity so frequent observation of glide crack movement can provide an index of instability. During spring 2011 in Glacier National Park, Montana, USA, we began an approach to track glide crack avalanche activity using a time-lapse camera focused on a southwest facing glide crack. This crack melted in-situ without failing as a glide avalanche, while other nearby glide cracks on north through southeast aspects failed. In spring 2012, a camera was aimed at a large and productive glide crack adjacent to the Going to the Sun Road. We captured three unique glide events in the field of view. Unfortunately, all of them either failed very quickly, or during periods of obscured view, so measurements of glide rate could not be obtained. However, we compared the hourly meteorological variables during the period of glide activity to the same variables prior to glide activity. The variables air temperature, relative humidity, air pressure, incoming and reflected long wave radiation, SWE, total precipitation, and snow depth were found to be statistically different for our cases examined. We propose that these are some of the potential precursors for glide avalanche activity, but do urge caution in their use, due to the simple approach and small data set size. It is hoped that by introducing a workable method to easily record glide crack movement, combined with ongoing analysis of the associated meteorological data, we will improve our understanding of when, or if, glide avalanche activity will ensue.

  20. Development an instrument assessing residents’ attitude towards professionalism lapses in training

    Science.gov (United States)

    2017-01-01

    Purpose Medical professionalism is a fundamental competency for all physicians and continuous development of professionalism during residency training is crucial. The purpose of this study was to develop an instrument assessing residents’ attitudes toward unprofessional behaviors. Methods A questionnaire survey was conducted in cooperation with the Korea Resident Association from May to July 2013. A total of 317 residents from seven university-affiliated hospitals in South Korea participated in the survey. Results In the exploratory factor analysis, seven factors were extracted from the data; factor loadings of the 44 items ranged between 0.40 and 0.89. Through iterative discussion, three items below 0.45 were deleted and one additional item was removed due to its irrelevance. Twelve items included in Factor 1 were divided into two different categories. A final version of the questionnaire containing 40 items in eight categories was assessed using confirmatory factor analysis. It was deemed to have a good fit; the root mean square error of approximation and comparative fit index were 0.07 and 0.9, respectively. The reliability (Cronbach’s α) of the inventory was 0.97. Conclusion The items of this instrument encompass a broad range of residents’ behaviors in clinical practice, research, and publication. In addition, it includes some types of misconduct that can be considered unique features of the authors’ cultural backgrounds. We recommend this instrument as an assessment tool to diagnose residents’ perceptions and attitudes towards professionalism lapses and to provide insight regarding potential improvement in professionalism education. PMID:28597871

  1. A method for quantifying cloud immersion in a tropical mountain forest using time-lapse photography

    Science.gov (United States)

    Bassiouni, Maoya; Scholl, Martha A.; Torres-Sanchez, Angel J.; Murphy, Sheila F.

    2017-01-01

    Quantifying the frequency, duration, and elevation range of fog or cloud immersion is essential to estimate cloud water deposition in water budgets and to understand the ecohydrology of cloud forests. The goal of this study was to develop a low-cost and high spatial-coverage method to detect occurrence of cloud immersion within a mountain cloud forest by using time-lapse photography. Trail cameras and temperature/relative humidity sensors were deployed at five sites covering the elevation range from the assumed lifting condensation level to the mountain peaks in the Luquillo Mountains of Puerto Rico. Cloud-sensitive image characteristics (contrast, the coefficient of variation and the entropy of pixel luminance, and image colorfulness) were used with a k-means clustering approach to accurately detect cloud-immersed conditions in a time series of images from March 2014 to May 2016. Images provided hydrologically meaningful cloud-immersion information while temperature-relative humidity data were used to refine the image analysis using dew point information and provided temperature gradients along the elevation transect. Validation of the image processing method with human-judgment based classification generally indicated greater than 90% accuracy. Cloud-immersion frequency averaged 80% at sites above 900 m during nighttime hours and 49% during daytime hours, and was consistent with diurnal patterns of cloud immersion measured in a previous study. Results for the 617 m site demonstrated that cloud immersion in the Luquillo Mountains rarely occurs at the previously-reported cloud base elevation of about 600 m (11% during nighttime hours and 5% during daytime hours). The framework presented in this paper will be used to monitor at a low cost and high spatial resolution the long-term variability of cloud-immersion patterns in the Luquillo Mountains, and can be applied to ecohydrology research at other cloud-forest sites or in coastal ecosystems with advective sea

  2. On the feasibility of time-lapse superconducting gravimetry for reservoir monitoring

    Science.gov (United States)

    Elliott, Elizabeth Judith

    The feasibility of monitoring fluid flow subsurface processes that result in density changes, using the iGrav superconducting gravimeter, is investigated. Practical targets include steam-assisted gravity drainage (SAGD) bitumen depletion and water pumping from aquifers, for which there is currently a void in low-impact, inexpensive monitoring techniques. This study demonstrates that the iGrav has the potential to be applied to multi-scale and diverse reservoirs. Gravity and gravity gradient signals are forward modeled for a real SAGD reservoir at two time steps, and for surface-fed and groundwater-fed aquifer pumping models, to estimate signal strength and directional dependency of water flow. Time-lapse gravimetry on small-scale reservoirs exhibits two obstacles, namely, a microgal sensitivity requirement and high noise levels in the vicinity of the reservoir. In this study, both limitations are overcome by proposing (i) a portable superconducting gravimeter, and (ii) a pair of instruments under various baseline geometries. This results in improved spatial resolution for locating depletion zones, as well as the cancellation of noise common in both instruments. Results indicate that a pair of iGrav superconducting gravimeters meet the sensitivity requirements and the spatial focusing desired to monitor SAGD bitumen migration at the reservoir scales. For SAGD reservoirs, the well pair separation, reservoir depth, and survey sampling determine the resolvability of individual well pair depletion patterns during the steam chamber rising phase, and general reservoir depletion patterns during the steam chamber spreading phase. Results show that monitoring water table elevation changes due to pumping and tracking whether groundwater or surface water is being extracted are feasible.

  3. ENVIRONMENTAL MONITORING OF LEAKS USING TIME LAPSED LONG ELECTRODE ELECTRICAL RESISTIVITY

    Energy Technology Data Exchange (ETDEWEB)

    MYERS DA; RUCKER DF; FINK JB; LOKE MH

    2009-12-16

    Highly industrialized areas pose challenges for surface electrical resistivity characterization due to metallic infrastructure. The infrastructure is typically more conductive than the desired targets and will mask the deeper subsurface information. These challenges may be minimized if steel-cased wells are used as long electrodes in the area near the target. We demonstrate a method of using long electrodes to electrically monitor a simulated leak from an underground storage tank with both synthetic examples and a field demonstration. The synthetic examples place a simple target of varying electrical properties beneath a very low resistivity layer. The layer is meant to replicate the effects of infrastructure. Both surface and long electrodes are tested on the synthetic domain. The leak demonstration for the field experiment is simulated by injecting a high conductivity fluid in a perforated well within the S tank farm at Hanford, and the resistivity measurements are made before and after the leak test. All data are processed in four dimensions, where a regularization procedure is applied in both the time and space domains. The synthetic test case shows that the long electrode ERM could detect relative changes in resistivity that are commensurate with the differing target properties. The surface electrodes, on the other hand, had a more difficult time matching the original target's footprint. The field results shows a lowered resistivity feature develop south of the injection site after cessation of the injections. The time lapsed regularization parameter has a strong influence on the differences in inverted resistivity between the pre and post injection datasets, but the interpretation of the target is consistent across all values of the parameter. The long electrode ERM method may provide a tool for near real-time monitoring of leaking underground storage tanks.

  4. Analysis and trends of precipitation lapse rate and extreme indices over north Sikkim eastern Himalayas under CMIP5ESM-2M RCPs experiments

    Science.gov (United States)

    Singh, Vishal; Goyal, Manish Kumar

    2016-01-01

    This paper draws attention to highlight the spatial and temporal variability in precipitation lapse rate (PLR) and precipitation extreme indices (PEIs) through the mesoscale characterization of Teesta river catchment, which corresponds to north Sikkim eastern Himalayas. A PLR rate is an important variable for the snowmelt runoff models. In a mountainous region, the PLR could be varied from lower elevation parts to high elevation parts. In this study, a PLR was computed by accounting elevation differences, which varies from around 1500 m to 7000 m. A precipitation variability and extremity were analysed using multiple mathematical functions viz. quantile regression, spatial mean, spatial standard deviation, Mann-Kendall test and Sen's estimation. For this reason, a daily precipitation, in the historical (years 1980-2005) as measured/observed gridded points and projected experiments for the 21st century (years 2006-2100) simulated by CMIP5 ESM-2 M model (Coupled Model Intercomparison Project Phase 5 Earth System Model 2) employing three different radiative forcing scenarios (Representative Concentration Pathways), utilized for the research work. The outcomes of this study suggest that a PLR is significantly varied from lower elevation to high elevation parts. The PEI based analysis showed that the extreme high intensity events have been increased significantly, especially after 2040s. The PEI based observations also showed that the numbers of wet days are increased for all the RCPs. The quantile regression plots showed significant increments in the upper and lower quantiles of the various extreme indices. The Mann-Kendall test and Sen's estimation tests clearly indicated significant changing patterns in the frequency and intensity of the precipitation indices across all the sub-basins and RCP scenario in an intra-decadal time series domain. The RCP8.5 showed extremity of the projected outcomes.

  5. Composite time-lapse computed tomography and micro finite element simulations: A new imaging approach for characterizing cement flows and mechanical benefits of vertebroplasty.

    Science.gov (United States)

    Stadelmann, Vincent A; Zderic, Ivan; Baur, Annick; Unholz, Cynthia; Eberli, Ursula; Gueorguiev, Boyko

    2016-02-01

    Vertebroplasty has been shown to reinforce weak vertebral bodies and reduce fracture risks, yet cement leakage is a major problem that can cause severe complications. Since cement flow is nearly impossible to control during surgery, small volumes of cement are injected, but then mechanical benefits might be limited. A better understanding of cement flows within bone structure is required to further optimize vertebroplasty and bone augmentation in general. We developed a novel imaging method, composite time-lapse CT, to characterize cement flow during injection. In brief, composite-resolution time-lapse CT exploits the qualities of microCT and clinical CT. The method consists in overlaying low-resolution time-lapse CT scans acquired during injection onto pre-operative high-resolution microCT scans, generating composite-resolution time-lapse CT series of cement flow within bone. In this in vitro study, composite-resolution time-lapse CT was applied to eight intact and five artificially fractured cadaveric vertebrae during vertebroplasty. The time-lapse scans were acquired at one-milliliter cement injection steps until a total of 10 ml cement was injected. The composite-resolution series were then converted into micro finite element models to compute strains distribution under virtual axial loading. Relocation of strain energy density within bone structure was observed throughout the progression of the procedure. Interestingly, the normalized effect of cement injection on the overall stiffness of the vertebrae was similar between intact and fractured specimens, although at different orders of magnitude. In conclusion, composite time-lapse CT can picture cement flows during bone augmentation. The composite images can also be easily converted into finite element models to compute virtual strain distributions under loading at every step of an injection, providing deeper understanding on the biomechanics of vertebroplasty. Copyright © 2015 IPEM. Published by Elsevier Ltd

  6. Attention: the claustrum.

    Science.gov (United States)

    Goll, Yael; Atlan, Gal; Citri, Ami

    2015-08-01

    The claustrum is a mysterious thin sheet of neurons lying between the insular cortex and the striatum. It is reciprocally connected with almost all cortical areas, including motor, somatosensory, visual, auditory, limbic, associative, and prefrontal cortices. In addition, it receives neuromodulatory input from subcortical structures. A decade ago, Sir Francis Crick and Christof Koch published an influential review proposing the claustrum as the 'seat of consciousness', spurring a revival of interest in the claustrum. We review the literature on the claustrum, emphasizing recent discoveries, and develop a detailed hypothesis describing a role for the claustrum in the segregation of attention. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Attracting attention. Posters.

    Science.gov (United States)

    1998-01-01

    Posters are useful in health education campaigns for announcing events, reinforcing messages communicated through other media, and providing a starting point for discussion. Posters should be clear enough to be understood on their own, sufficiently striking to attract attention, and displayed in places where they will be seen by the target population. The posters should be changed regularly or people will stop noticing them. All posters should be carefully planned and pretested with the intended target group. Use of color can help ensure that figures and symbols stand out from the background and lower case letters are easier to read than all capital letters. Finally, the lettering should be neat and even.

  8. Attention decay in science

    CERN Document Server

    Parolo, Pietro Della Briotta; Ghosh, Rumi; Huberman, Bernardo A; Kaski, Kimmo; Fortunato, Santo

    2015-01-01

    The exponential growth in the number of scientific papers makes it increasingly difficult for researchers to keep track of all the publications relevant to their work. Consequently, the attention that can be devoted to individual papers, measured by their citation counts, is bound to decay rapidly. In this work we make a thorough study of the life-cycle of papers in different disciplines. Typically, the citation rate of a paper increases up to a few years after its publication, reaches a peak and then decreases rapidly. This decay can be described by an exponential or a power law behavior, as in ultradiffusive processes, with exponential fitting better than power law for the majority of cases. The decay is also becoming faster over the years, signaling that nowadays papers are forgotten more quickly. However, when time is counted in terms of the number of published papers, the rate of decay of citations is fairly independent of the period considered. This indicates that the attention of scholars depends on th...

  9. Promoting the return of lapsed blood donors: a seven-arm randomized controlled trial of the question-behavior effect.

    Science.gov (United States)

    Godin, Gaston; Germain, Marc; Conner, Mark; Delage, Gilles; Sheeran, Paschal

    2014-07-01

    This study tested key variations in the question-behavior effect against a control condition or an implementation intention condition on returning to give blood among lapsed donors (individuals who had not given blood in the past 2 years). At baseline, 7,000 lapsed donors were randomized to 1 of 6 experimental conditions or to a control condition. Participants in the experimental conditions were asked to complete a 6-item postal questionnaire assessing intentions only, interrogative intention, moral norm plus intention, anticipated regret plus intention, positive self-image plus intention, or implementation intentions. OBJECTIVE measures of behavior were obtained 6 and 15 months later. The frequency of registrations to give blood over the next 6 and 15 months was measured. Intention-to-treat analysis of the frequency of registrations (GENMOD procedure, Poisson distribution) indicated main effects for condition (experimental vs. control) at both 6 months, χ²(1) = 4.64, p < .05, and 15 months, χ²(1) = 5.88, p < .05. Positive self-image and implementation intention interventions outperformed the control condition at 6 months. At 15 months, standard intention, interrogative intention, and regret plus intention conditions showed more frequent registrations compared with control and were just as effective as implementation intention formation. Moderation analysis showed that the moral norm and positive self-image conditions were significant for first-time (1 previous donation) but not repeat (2 or more previous donations) donors. The question-behavior effect can be used to reinvigorate blood donation among lapsed donors, and can be as effective as forming implementation intentions.

  10. Obstetric and perinatal outcomes of pregnancies conceived with embryos cultured in a time-lapse monitoring system.

    Science.gov (United States)

    Insua, Maria Fernanda; Cobo, Ana Cristina; Larreategui, Zaloa; Ferrando, Marcos; Serra, Vicente; Meseguer, Marcos

    2017-09-01

    To compare obstetric and perinatal outcomes of singleton pregnancies resulting from embryos incubated in a time-lapse system (TLS) with those of embryos grown in standard IVF incubators (SI). Retrospective description of a cohort of patients who conceived during a randomized, controlled trial. Private university-affiliated IVF center. Of 856 randomized patients, 378 gave birth to a live-born infant: 216 of the deliveries originated from embryos incubated in TLS, and 162 deliveries were from embryos cultured in SI. Embryo incubation and selection in TLS. Delivery and neonatal outcomes. No significant differences were observed in the baseline characteristics of the study population. The delivery rate was 49.3% (TLS) vs. 40.0% (SI), and multiple deliveries were higher in the TLS group: 31.0% (67 of 216) vs. 24.7% (40 of 162) in the SI group. When singleton pregnancies were analyzed no differences were found between the two groups in the rate of obstetric problems with respect to weeks at delivery: 38.8 (95% confidence interval [CI] 38.4-39.1) (TLS) vs. 39.5 (95% CI 38.0-39.9) (SI); preterm births (outcomes such as birth weight: 3,163 g (95% CI 3,035-3,292 g) (TLS) vs. 3,074 (95% CI 2,913-3,236) (SI); low birth weight (obstetric and perinatal outcomes when a time-lapse incubator was used rather than a more widely used conventional incubator. As far as we know this is the first report from a randomized study of the neonatal outcomes of time-lapse monitoring. Our results suggest that this technology is an effective and safe alternative for embryo incubation, though trials of larger numbers of patients are required to further confirm our conclusions. NCT01549262. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  11. Spatiotemporal monitoring of soil water content profiles in an irrigated field using probabilistic inversion of time-lapse EMI data

    KAUST Repository

    Moghadas, Davood

    2017-10-17

    Monitoring spatiotemporal variations of soil water content (θ) is important across a range of research fields, including agricultural engineering, hydrology, meteorology and climatology. Low frequency electromagnetic induction (EMI) systems have proven to be useful tools in mapping soil apparent electrical conductivity (σa) and soil moisture. However, obtaining depth profile water content is an area that has not been fully explored using EMI. To examine this, we performed time-lapse EMI measurements using a CMD mini-Explorer sensor along a 10 m transect of a maize field over a 6 day period. Reference data were measured at the end of the profile via an excavated pit using 5TE capacitance sensors. In order to derive a time-lapse, depth-specific subsurface image of electrical conductivity (σ), we applied a probabilistic sampling approach, DREAM(ZS), on the measured EMI data. The inversely estimated σ values were subsequently converted to θ using the Rhoades et al. (1976) petrophysical relationship. The uncertainties in measured σa, as well as inaccuracies in the inverted data, introduced some discrepancies between estimated σ and reference values in time and space. Moreover, the disparity between the measurement footprints of the 5TE and CMD Mini-Explorer sensors also led to differences. The obtained θ permitted an accurate monitoring of the spatiotemporal distribution and variation of soil water content due to root water uptake and evaporation. The proposed EMI measurement and modeling technique also allowed for detecting temporal root zone soil moisture variations. The time-lapse θ monitoring approach developed using DREAM(ZS) thus appears to be a useful technique to understand spatiotemporal patterns of soil water content and provide insights into linked soil moisture vegetation processes and the dynamics of soil moisture/infiltration processes.

  12. Role of Interstitial Branching in the Development of Visual Corticocortical Connections: A Time-Lapse and Fixed-Tissue Analysis

    Science.gov (United States)

    Ruthazer, Edward S.; Bachleda, Amelia R.; Olavarria, Jaime F.

    2013-01-01

    We combined fixed-tissue and time-lapse analyses to investigate the axonal branching phenomena underlying the development of topographically organized ipsilateral projections from area 17 to area 18a in the rat. These complementary approaches allowed us to relate static, large-scale information provided by traditional fixed-tissue analysis to highly dynamic, local, small-scale branching phenomena observed with two-photon time-lapse microscopy in acute slices of visual cortex. Our fixed-tissue data revealed that labeled area 17 fibers invaded area 18a gray matter at topographically restricted sites, reaching superficial layers in significant numbers by postnatal day 6 (P6). Moreover, most parental axons gave rise to only one or occasionally a small number of closely spaced interstitial branches beneath 18a. Our time-lapse data showed that many filopodium-like branches emerged along parental axons in white matter or deep layers in area 18a. Most of these filopo-dial branches were transient, often disappearing after several minutes to hours of exploratory extension and retraction. These dynamic behaviors decreased significantly from P4, when the projection is first forming, through the second postnatal week, suggesting that the expression of, or sensitivity to, cortical cues promoting new branch addition in the white matter is developmentally down-regulated coincident with gray matter innervation. Together, these data demonstrate that the development of topographically organized corticocortical projections in rats involves extensive exploratory branching along parental axons and invasion of cortex by only a small number of interstitial branches, rather than the widespread innervation of superficial cortical layers by an initially exuberant population of branches. PMID:21031561

  13. A multimethod Global Sensitivity Analysis to aid the calibration of geomechanical models via time-lapse seismic data

    Science.gov (United States)

    Price, D. C.; Angus, D. A.; Garcia, A.; Fisher, Q. J.; Parsons, S.; Kato, J.

    2018-03-01

    Time-lapse seismic attributes are used extensively in the history matching of production simulator models. However, although proven to contain information regarding production induced stress change, it is typically only loosely (i.e. qualitatively) used to calibrate geomechanical models. In this study we conduct a multimethod Global Sensitivity Analysis (GSA) to assess the feasibility and aid the quantitative calibration of geomechanical models via near-offset time-lapse seismic data. Specifically, the calibration of mechanical properties of the overburden. Via the GSA, we analyse the near-offset overburden seismic traveltimes from over 4000 perturbations of a Finite Element (FE) geomechanical model of a typical High Pressure High Temperature (HPHT) reservoir in the North Sea. We find that, out of an initially large set of material properties, the near-offset overburden traveltimes are primarily affected by Young's modulus and the effective stress (i.e. Biot) coefficient. The unexpected significance of the Biot coefficient highlights the importance of modelling fluid flow and pore pressure outside of the reservoir. The FE model is complex and highly nonlinear. Multiple combinations of model parameters can yield equally possible model realizations. Consequently, numerical calibration via a large number of random model perturbations is unfeasible. However, the significant differences in traveltime results suggest that more sophisticated calibration methods could potentially be feasible for finding numerous suitable solutions. The results of the time-varying GSA demonstrate how acquiring multiple vintages of time-lapse seismic data can be advantageous. However, they also suggest that significant overburden near-offset seismic time-shifts, useful for model calibration, may take up to 3 yrs after the start of production to manifest. Due to the nonlinearity of the model behaviour, similar uncertainty in the reservoir mechanical properties appears to influence overburden

  14. Near real-time imaging of molasses injections using time-lapse electrical geophysics at the Brandywine DRMO, Brandywine, Maryland

    Science.gov (United States)

    Versteeg, R. J.; Johnson, T.; Major, B.; Day-Lewis, F. D.; Lane, J. W.

    2010-12-01

    Enhanced bioremediation, which involves introduction of amendments to promote biodegradation, increasingly is used to accelerate cleanup of recalcitrant compounds and has been identified as the preferred remedial treatment at many contaminated sites. Although blind introduction of amendments can lead to sub-optimal or ineffective remediation, the distribution of amendment throughout the treatment zone is difficult to measure using conventional sampling. Because amendments and their degradation products commonly have electrical properties that differ from those of ambient soil, time-lapse electrical geophysical monitoring has the potential to verify amendment emplacement and distribution. In order for geophysical monitoring to be useful, however, results of the injection ideally should be accessible in near real time. In August 2010, we demonstrated the feasibility of near real-time, autonomous electrical geophysical monitoring of amendment injections at the former Defense Reutilization and Marketing Office (DRMO) in Brandywine, Maryland. Two injections of about 1000 gallons each of molasses, a widely used amendment for enhanced bioremediation, were monitored using measurements taken with borehole and surface electrodes. During the injections, multi-channel resistance data were recorded; data were transmitted to a server and processed using a parallel resistivity inversion code; and results in the form of time-lapse imagery subsequently were posted to a website. This process occurred automatically without human intervention. The resulting time-lapse imagery clearly showed the evolution of the molasses plume. The delay between measurements and online delivery of images was between 45 and 60 minutes, thus providing actionable information that could support decisions about field procedures and a check on whether amendment reached target zones. This experiment demonstrates the feasibility of using electrical imaging as a monitoring tool both during amendment emplacement

  15. Summer-time Mass Balance of Wolverine Glacier, Alaska, Derived from Ground-based Time-lapse Microgravity Measurements

    Science.gov (United States)

    Young, E. V.; Muto, A.; Babcock, E.

    2016-12-01

    Monitoring the mass balance of alpine glaciers is important because alpine glaciers presently account for about half of the cryospheric contribution to the global sea-level rise. Mass balance measurements of alpine glaciers have predominantly relied upon glaciological and hydrological methods. However, these methods can be logistically costly and have potential extrapolation errors. Remote sensing approaches, such as gravimetric methods using data from GRACE satellite missions, have provided monthly mass-balance estimates of aggregates of alpine glaciers but their spatial resolution is far too large for studying a single glacier. On the other hand, ground-based time-lapse microgravity geophysical measurements can potentially circumvent some of the disadvantages of the glaciological and hydrological methods. It may detect the change in a single glacier's mass and its spatial distribution. We conducted ground-based time-lapse microgravity surveys on Wolverine Glacier, Alaska, in May and August of 2016, using a Scintrex CG-5 Autograv gravimeter. We collected data at seventy-nine individual stations on the glacier, roughly five stations per square kilometer. We included repeat-station and base-station measurements made at least twice a day for instrumental drift control. The uncertainty of our gravity measurements is better than 0.03 mGal, which is about 0.7 meters water equivalent of surface mass balance. Our summer-time mass balance of Wolverine Glacier determined from the time-lapse gravity measurements is independent of that derived from the stake-network or stream-gauge measurements, and could provide spatial insight into the mass balance process on Wolverine Glacier and similar glaciers.

  16. Time-lapse and UAV Thermal Imaging of Glacial and Periglacial Environments in the Peruvian Andes (Cordillera Blanca, Peru)

    Science.gov (United States)

    McKenzie, J. M.; Wigmore, O.; Aubry-Wake, C.; Mark, B. G.; Hellstrom, R. A.; Lautz, L.

    2015-12-01

    In the tropics, the acquisition of high-resolution geospatial data of high-mountain glacial and periglacial systems presents unique challenges due to remote site access and very high elevations. For glaciers and hydrologic systems, a key variable of interest is surface temperature as it constrains glacier melt rates, traces hydrologic processes, and is needed for the calibration of energy budget models. We present results from two studies that acquired high resolution temperature data from the Cuchillacocha Glacier, Peru (9.24°S, 77.21°W). The glacier resides on the western drainage of the Cordillera Blanca with an elevation range of 4700 to 6096 m. In the first study we use high resolution time-lapse infrared imagery (5-10 minute interval over 3 days; 0.6 m2 pixel size) to observe diel changes in the surface energy budget of the glacier and to demonstrate how radiation from bare rock adjacent to the glacier may affect melt rates. In the second study we use a newly developed, inexpensive unmanned aerial vehicle (UAV) for high resolution multispectral mapping of the glacier (2 cm resolution orthomosaic and 5 cm resolution DEM). We present results showing how the time-lapse and the high-resolution UAV imagery can be combined to further strengthen our understanding of the Cuchillacocha Glacier's energy budget and possible insights about turbulent heat fluxes. While the new instruments provide unprecedented data acquisition capabilities, there is an outstanding need for proper data correction. Spatial/thermal control points and post-processing algorithms are needed to produce quantifiable datasets. For example, our post-processed time-lapse imagery has an r2 > 0.9 after emissivity, transmissivity and offset corrections.

  17. Spatiotemporal monitoring of soil water content profiles in an irrigated field using probabilistic inversion of time-lapse EMI data

    Science.gov (United States)

    Moghadas, Davood; Jadoon, Khan Zaib; McCabe, Matthew F.

    2017-12-01

    Monitoring spatiotemporal variations of soil water content (θ) is important across a range of research fields, including agricultural engineering, hydrology, meteorology and climatology. Low frequency electromagnetic induction (EMI) systems have proven to be useful tools in mapping soil apparent electrical conductivity (σa) and soil moisture. However, obtaining depth profile water content is an area that has not been fully explored using EMI. To examine this, we performed time-lapse EMI measurements using a CMD mini-Explorer sensor along a 10 m transect of a maize field over a 6 day period. Reference data were measured at the end of the profile via an excavated pit using 5TE capacitance sensors. In order to derive a time-lapse, depth-specific subsurface image of electrical conductivity (σ), we applied a probabilistic sampling approach, DREAM(ZS) , on the measured EMI data. The inversely estimated σ values were subsequently converted to θ using the Rhoades et al. (1976) petrophysical relationship. The uncertainties in measured σa, as well as inaccuracies in the inverted data, introduced some discrepancies between estimated σ and reference values in time and space. Moreover, the disparity between the measurement footprints of the 5TE and CMD Mini-Explorer sensors also led to differences. The obtained θ permitted an accurate monitoring of the spatiotemporal distribution and variation of soil water content due to root water uptake and evaporation. The proposed EMI measurement and modeling technique also allowed for detecting temporal root zone soil moisture variations. The time-lapse θ monitoring approach developed using DREAM(ZS) thus appears to be a useful technique to understand spatiotemporal patterns of soil water content and provide insights into linked soil moisture vegetation processes and the dynamics of soil moisture/infiltration processes.

  18. Analysis of Zebrafish Kidney Development with Time-lapse Imaging Using a Dissecting Microscope Equipped for Optical Sectioning.

    Science.gov (United States)

    Perner, Birgit; Schnerwitzki, Danny; Graf, Michael; Englert, Christoph

    2016-04-07

    In order to understand organogenesis, the spatial and temporal alterations that occur during development of tissues need to be recorded. The method described here allows time-lapse analysis of normal and impaired kidney development in zebrafish embryos by using a fluorescence dissecting microscope equipped for structured illumination and z-stack acquisition. To visualize nephrogenesis, transgenic zebrafish (Tg(wt1b:GFP)) with fluorescently labeled kidney structures were used. Renal defects were triggered by injection of an antisense morpholino oligonucleotide against the Wilms tumor gene wt1a, a factor known to be crucial for kidney development. The advantage of the experimental setup is the combination of a zoom microscope with simple strategies for re-adjusting movements in x, y or z direction without additional equipment. To circumvent focal drift that is induced by temperature variations and mechanical vibrations, an autofocus strategy was applied instead of utilizing a usually required environmental chamber. In order to re-adjust the positional changes due to a xy-drift, imaging chambers with imprinted relocation grids were employed. In comparison to more complex setups for time-lapse recording with optical sectioning such as confocal laser scanning or light sheet microscopes, a zoom microscope is easy to handle. Besides, it offers dissecting microscope-specific benefits such as high depth of field and an extended working distance. The method to study organogenesis presented here can also be used with fluorescence stereo microscopes not capable of optical sectioning. Although limited for high-throughput, this technique offers an alternative to more complex equipment that is normally used for time-lapse recording of developing tissues and organ dynamics.

  19. STcorr: An IDL code for image based normalization of lapse rate and illumination effects on nighttime TIR imagery

    Science.gov (United States)

    Ulusoy, İnan; Labazuy, Philippe; Aydar, Erkan

    2012-06-01

    Thermal infrared imagery (TIR) is a useful tool to detect and quantify the surface temperature anomalies associated with geothermal fields. Accurate detection of anomalies in surface temperature is an important aspect of geothermal research. Although day-time TIR images have long been used for temperature anomaly mapping, the increase in the spatial resolution and the number of acquisitions of nighttime thermal imagery provide new perspectives to the remote geothermal monitoring and exploration. However, the nighttime thermal imagery requires appropriate corrections in order to minimize some major artefacts. These corrections are namely: the masking of small scale thermal anomalies by the lapse rate, the relict diurnal heat due to the radiation of sun and the slope effect. Moreover, the correction of nighttime TIR imagery according to the altitude, slope aspect and the slope of the study area provide more reliable data. STcorr is an Interactive Data Language (IDL) code for the correction of altitude, aspect and slope effects in nighttime thermal imagery using image based polynomial regression analysis. Standard ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) Surface Kinetic Temperature (ST) image and Digital Elevation Model (DEM) are used to calculate a lapse rate model. Upon the retrieval of lapse rate, an illumination correction is performed based on the relationship between the corrected image and the aspect and slope images, interactive and "step by step" structure of the code permit user to improve the quality of the output. An ASTER nighttime ST image of the Mt. Nemrut volcano has been corrected using STcorr as an example. The procedure improves the reliability of the output after the retrieval of altitude, aspect and slope effects. Thermal anomalies observed in the Mt. Nemrut are consistent with the hydrothermal activity and the hot spots detected by self-potential measurements in the area.

  20. Quantifying the drivers of European precipitation changes: Large-scale thermodynamics, lapse-rate and circulation changes

    Science.gov (United States)

    Kröner, Nico; Lüthi, Daniel; Fischer, Erich; Kotlarski, Sven; Schär, Christoph

    2017-04-01

    Recent coordinated climate modeling studies such as CMIP5 or CORDEX provide a unique set of simulations for assessing projected changes in the hydrological cycle. Yet the reasons for the project changes often remains obscure. Here we examine, by extending a previous study (Kröner et al., 2016, DOI:10.1007/s00382-016-3276-3), the large-scale drivers for changes in European precipitation statistics (mean, intensity, frequency, heavy precipitation and dry days). Regional climate model ensembles suggest a bipolar climate change pattern over Europe, with decreasing (increasing) mean precipitation and wet-day frequency in the south (north). Increases in precipitation intensity and occurrence of heavy events show a similar pattern but the increases extend further south. An extended surrogate approach is applied to disentangle the influence of large-scale thermodynamic, circulation and lapse-rate changes on the projections. Additionally a subset of a multi-model ensemble (EURO-CORDEX) is utilized to evaluate the findings. The thermodynamic effect is found to increase precipitation intensity, but to have no influence on the precipitation frequency. Its influence on heavy precipitation events is stronger than on mean precipitation. The large-scale circulation in contrast is decreasing the precipitation frequency and has only a small influence on precipitation intensity. In general its influence becomes weaker for heavy precipitation events. The lapse-rate effect is important in summer over southern Europe. For this region and season, its effect is as strong as the large-scale circulation effect, and it is also decreasing precipitation frequency. The strong influence of the lapse-rate effect on Mediterranean precipitation change is quantified for the first time in this study.

  1. Effect of time lapse on the diagnostic accuracy of cone beam computed tomography for detection of vertical root fractures

    Energy Technology Data Exchange (ETDEWEB)

    Eskandarloo, Amir; Shokri, Abbas, E-mail: Dr.a.shokri@gmail.com [Dental Research Center, Department of Oral and Maxillofacial Radiology, Hamadan University of Medical Sciences, Hamadan (Iran, Islamic Republic of); Asl, Amin Mahdavi [Department of Oral and Maxillofacial Radiology, Golestan University of Medical Sciences, Gorgan (Iran, Islamic Republic of); Jalalzadeh, Mohsen [Department of Endodontics, Hamadan University of Medical Sciences, Hamadan (Iran, Islamic Republic of); Tayari, Maryam [Department of Pedodontics, Golestan University of Medical Sciences, Gorgan (Iran, Islamic Republic of); Hosseinipanah, Mohammad [Department of Anatomy, School of Medicine, Hamadan University of Medical Sciences, Hamadan (Iran, Islamic Republic of); Fardmal, Javad [Research Center for Health Sciences and Department of Epidemiology and Biostatistics, School of Public Health, Hamadan University of Medical Sciences, Hamadan (Iran, Islamic Republic of)

    2016-01-15

    Accurate and early diagnosis of vertical root fractures (VRFs) is imperative to prevent extensive bone loss and unnecessary endodontic and prosthodontic treatments. The aim of this study was to assess the effect of time lapse on the diagnostic accuracy of cone beam computed tomography (CBCT) for VRFs in endodontically treated dog’s teeth. Forty eight incisors and premolars of three adult male dogs underwent root canal therapy. The teeth were assigned to two groups: VRFs were artificially induced in the first group (n=24) while the teeth in the second group remained intact (n=24). The CBCT scans were obtained by NewTom 3G unit immediately after inducing VRFs and after one, two, three, four, eight, 12 and 16 weeks. Three oral and maxillofacial radiologists blinded to the date of radiographs assessed the presence/absence of VRFs on CBCT scans. The sensitivity, specificity and accuracy values were calculated and data were analyzed using SPSS v.16 software and ANOVA. The total accuracy of detection of VRFs immediately after surgery, one, two, three, four, eight, 12 and 16 weeks was 67.3%, 68.7%, 66.6%, 64.6%, 64.5%, 69.4%, 68.7%, 68% respectively. The effect of time lapse on detection of VRFs was not significant (p>0.05). Overall sensitivity, specificity and accuracy of CBCT for detection of VRFs were 74.3%, 62.2%, 67.2% respectively. Cone beam computed tomography is a valuable tool for detection of VRFs. Time lapse (four months) had no effect on detection of VRFs on CBCT scans. (author)

  2. Penicillin induced persistence in Chlamydia trachomatis: high quality time lapse video analysis of the developmental cycle.

    Directory of Open Access Journals (Sweden)

    Rachel J Skilton

    Full Text Available BACKGROUND: Chlamydia trachomatis is a major human pathogen with a unique obligate intracellular developmental cycle that takes place inside a modified cytoplasmic structure known as an inclusion. Following entry into a cell, the infectious elementary body (EB differentiates into a non-infectious replicative form known as a reticulate body (RB. RBs divide by binary fission and at the end of the cycle they redifferentiate into EBs. Treatment of C.trachomatis with penicillin prevents maturation of RBs which survive and enlarge to become aberrant RBs within the inclusion in a non-infective persistent state. Persistently infected individuals may be a reservoir for chlamydial infection. The C.trachomatis genome encodes the enzymes for peptidoglycan (PG biosynthesis but a PG sacculus has never been detected. This coupled to the action of penicillin is known as the chlamydial anomaly. We have applied video microscopy and quantitative DNA assays to the chlamydial developmental cycle to assess the effects of penicillin treatment and establish a framework for investigating penicillin induced chlamydial persistence. PRINCIPAL FINDINGS: Addition of penicillin at the time of cell infection does not prevent uptake and the establishment of an inclusion. EB to RB transition occurs but bacterial cytokinesis is arrested by the second binary fission. RBs continue to enlarge but not divide in the presence of penicillin. The normal developmental cycle can be recovered by the removal of penicillin although the large, aberrant RBs do not revert to the normal smaller size but remain present to the completion of the developmental cycle. Chromosomal and plasmid DNA replication is unaffected by the addition of penicillin but the arrest of bacterial cytokinesis under these conditions results in RBs accumulating multiple copies of the genome. CONCLUSIONS: We have applied video time lapse microscopy to the study of the chlamydial developmental cycle. Linked with accurate

  3. Globally referenced real time monitoring of mass movements using monoscopic time-lapse photography.

    Science.gov (United States)

    Kenner, Robert; Phillips, Marcia; Buchroithner, Manfred

    2016-04-01

    The creep movement of a rock glacier was monitored in daily resolution using images of an automatic in-situ time-lapse camera (AC). Displacements were calculated between the images in 2D image coordinates using the imaging velocimetry algorithm of Roesgen and Totaro, 1995. To georeference and scale these displacements, a creep velocity field captured once by a terrestrial laser scan (TLS) repeat measurement was used. The laser scan point cloud and the creep velocity vector field were projected in image coordinates of the AC to obtain a georeferencing mask, a scale mask and an azimuth mask for the 2D displacements calculated between two images. The scale mask was obtained by comparing the TLS derived displacement vectors with those of the AC, referring to a common measurement period. The automatic procedure includes the following work steps: 1. Offsets between two images are identified and corrected based on image parts representing unchanged terrain. 2. 2D displacements are calculated between all chronological image sequences. 3. Faulty displacement vectors are eliminated based on a predefined threshold for spatial direction differences. 4. The remaining displacements are georeferenced, scaled and attributed with individual displacement directions (azimuths) in global coordinates. 5. In addition to the displacement values, displacement velocities and accelerations are calculated using the date of the images. 6. For chronologically successive displacement vector fields, the spatial mean of the relative velocity is defined and expressed as a percentage of the first displacement velocity in the series. The time series of the relative velocities is expressed in chart form. 7. The spatial resolution of all georeferenced output data sets is homogenized, as they were influenced by the central projection of the photos. The described procedure proved to be a reliable, low cost method to monitor mass wasting processes. Even under difficult conditions, like thin snow coverage

  4. Unravelling complex processes during effusive volcanic eruptions using high resolution time-lapse imagery

    Science.gov (United States)

    Pinkerton, H.; James, M. R.; Applegarth, L. J.

    2010-12-01

    While lava flow models are being used successfully to predict areas that are liable to be covered during effusive eruptions, lavas that erupt for more than a few weeks have the potential to develop lava tubes, ephemeral vents and accidental breaches leading to new lava flow pathways. The processes resulting in each of these are not fully understood. Some of these may be related to variations in effusion rate during the eruption; others may be topographically-controlled. There is a therefore a need for a detailed analysis of the development of flow fields to improve our understanding of the factors that control maximum flow length of individual flows, ephemeral vent formation, accidental breaches, and the transition from channelled flows to tube-fed flows. During the final month of the 13 May 2008 to 6 July 2009 eruption into the Valle del Bove on Etna, four Canon EOS 450D cameras (3 visible and one modified to collect infrared images) were installed at critical locations around the rim of the Valle del Bove (Schiena dell’ Àsino, Monte Zoccolaro and Pizzi Deneri) to record the emplacement and development of lava flows erupted during this period. Some of the cameras collected images every 5 minutes, while others collected images every 15 minutes. During this time, active lava flows were restricted to the upper part of a large delta, individual flows lasted between a few hours and a few days and they had lengths ranging from tens to hundreds of metres. The resulting time-lapse images reveal significant reduction in mean flow lengths towards the end of the observation period; this is compatible with a marked decrease in effusion rate. Superimposed on this reduction, there were marked variations in effusion rate on shorter time periods. These short-term changes played a significant role in the development of breakouts and ephemeral vent formation and reactivation. The images also place constraints on the relative importance of factors controlling the maximum flow

  5. Soundscape and Noise Exposure Monitoring in a Marine Protected Area Using Shipping Data and Time-Lapse Footage.

    Science.gov (United States)

    Merchant, Nathan D; Pirotta, Enrico; Barton, Tim R; Thompson, Paul M

    2016-01-01

    We review recent work that developed new techniques for underwater noise assessment that integrate acoustic monitoring with automatic identification system (AIS) shipping data and time-lapse video, meteorological, and tidal data. Two sites were studied within the Moray Firth Special Area of Conservation (SAC) for bottlenose dolphins, where increased shipping traffic is expected from construction of offshore wind farms outside the SAC. Noise exposure varied markedly between the sites, and natural and anthropogenic contributions were characterized using multiple data sources. At one site, AIS-operating vessels accounted for total cumulative sound exposure (0.1-10 kHz), suggesting that noise modeling using the AIS would be feasible.

  6. Forward modeling to investigate inversion artifacts resulting from time-lapse electrical resistivity tomography during rainfall simulations

    Science.gov (United States)

    Carey, Austin M.; Paige, Ginger B.; Carr, Bradley J.; Dogan, Mine

    2017-10-01

    Time-lapse electrical resistivity tomography (ERT) is commonly used as a minimally invasive tool to study infiltration processes. In 2014, we conducted field studies coupling variable intensity rainfall simulation with high-resolution ERT to study the real-time partitioning of rainfall into surface and subsurface response. The significant contrast in resistivity in the subsurface from large changes in subsurface moisture resulted in artifacts during the inversion process of the time-lapse ERT data collected using a dipole-dipole electrode array. These artifacts, which are not representative of real subsurface moisture dynamics, have been shown to arise during time-lapse inversion of ERT data and may be subject to misinterpretation. Forward modeling of the infiltration process post field experiments using a two-layer system (saprolite overlain by a soil layer) was used to generate synthetic datasets. The synthetic data were used to investigate the influence of both changes in volumetric moisture content and electrode configuration on the development of the artifacts identified in the field datasets. For the dipole-dipole array, we found that a decrease in the resistivity of the bottom layer by 67% resulted in a 50% reduction in artifact development. Artifacts for the seven additional array configurations tested, ranged from a 19% increase in artifact development (using an extended dipole-dipole array) to as much as a 96% decrease in artifact development (using a wenner-alpha array), compared to that of the dipole-dipole array. Moreover, these arrays varied in their ability to accurately delineate the infiltration front. Model results showed that the modified pole-dipole array was able to accurately image the infiltration zone and presented fewer artifacts for our experiments. In this study, we identify an optimal array type for imaging rainfall-infiltration dynamics that reduces artifacts. The influence of moisture contrast between the infiltrating water and the

  7. A Modular and Affordable Time-Lapse Imaging and Incubation System Based on 3D-Printed Parts, a Smartphone, and Off-The-Shelf Electronics.

    Science.gov (United States)

    Hernández Vera, Rodrigo; Schwan, Emil; Fatsis-Kavalopoulos, Nikos; Kreuger, Johan

    2016-01-01

    Time-lapse imaging is a powerful tool for studying cellular dynamics and cell behavior over long periods of time to acquire detailed functional information. However, commercially available time-lapse imaging systems are expensive and this has limited a broader implementation of this technique in low-resource environments. Further, the availability of time-lapse imaging systems often present workflow bottlenecks in well-funded institutions. To address these limitations we have designed a modular and affordable time-lapse imaging and incubation system (ATLIS). The ATLIS enables the transformation of simple inverted microscopes into live cell imaging systems using custom-designed 3D-printed parts, a smartphone, and off-the-shelf electronic components. We demonstrate that the ATLIS provides stable environmental conditions to support normal cell behavior during live imaging experiments in both traditional and evaporation-sensitive microfluidic cell culture systems. Thus, the system presented here has the potential to increase the accessibility of time-lapse microscopy of living cells for the wider research community.

  8. Attention and Distraction

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    2010-01-01

    the fact that the behaviour of many visitors is characterised by a certain restlessness and distraction. The article suggests that, in contradistinction to traditional disciplines of art like painting and sculpture, video installations seem to stimulate a "reception in distraction" (Walter Benjamin......This article aims to examine the interrelationship between attention and distraction in the reception of video installation art, a genre which is commonly associated with "immersion" and an intensified feeling of presence in the discourses on new media art and installation art. This tends to veil......) that is at odds with the ideal of a reception in concentration that governs the institutions of fine art as well as aesthetic theory. It intends to demonstrate how the experience of video installation art can only be understood by recognising that the close connections between, on the one hand, video art and...

  9. Attention Deficit Hyperactivity Disorder

    Science.gov (United States)

    Matthews, Marguerite; Nigg, Joel T.

    2014-01-01

    Over the last two decades, there have been numerous technical and methodological advances available to clinicians and researchers to better understand attention deficit hyperactivity disorder (ADHD) and its etiology. Despite the growing body of literature investigating the disorder’s pathophysiology, ADHD remains a complex psychiatric disorder to characterize. This chapter will briefly review the literature on ADHD, with a focus on its history, the current genetic insights, neurophysiologic theories, and the use of neuroimaging to further understand the etiology. We address some of the major concerns that remain unclear about ADHD, including subtype instability, heterogeneity, and the underlying neural correlates that define the disorder. We highlight that the field of ADHD is rapidly evolving; the descriptions provided here will hopefully provide a sturdy foundation for which to build and improve our understanding of the disorder. PMID:24214656

  10. Octave effect in auditory attention

    National Research Council Canada - National Science Library

    Tobias Borra; Huib Versnel; Chantal Kemner; A. John van Opstal; Raymond van Ee

    2013-01-01

    ... tones. Current auditory models explain this phenomenon by a simple bandpass attention filter. Here, we demonstrate that auditory attention involves multiple pass-bands around octave-related frequencies above and below the cued tone...

  11. Attention deficit hyperactivity disorder (ADHD)

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001551.htm Attention deficit hyperactivity disorder To use the sharing features on this page, please enable JavaScript. Attention deficit hyperactivity disorder (ADHD) is a problem caused by the presence ...

  12. Chewing and Attention: A Positive Effect on Sustained Attention

    Directory of Open Access Journals (Sweden)

    Yoshiyuki Hirano

    2015-01-01

    Full Text Available Chewing is crushing food not only to aid swallowing and digestion, but also to help stress relief and regulate cognitive function, especially in attention. It is well known that chewing gum is used for sleepiness prevention during work, learning, and driving, suggesting a link between chewing and sustained attention. We hypothesized that chewing elevates attention and/or alertness, leading to improvements in cognitive performance. We carried out a systematic review of the PubMed database. We inspected the attributes of effects on attention in studies investigating the effects of chewing on attention or alertness conducted with pre-post design in healthy subjects, except elderly. We identified 151 references, 22 of which were included: 14 (64% showed positive attributes of effects on attention, 1 (5% showed negative attributes of effects on attention, 5 (23% showed both positive and negative attributes of effects on attention, and 2 (9% showed no significant attributes of effects on attention. Thus, positive attributes of effects of chewing on attention, especially on sustained attention, were shown in over half of the reports. These effects also appeared with improvement in mood and stress relief and were influenced by time-on-task effect. Further studies are needed, but chewing could be useful for modifying cognitive function.

  13. Chewing and attention: a positive effect on sustained attention.

    Science.gov (United States)

    Hirano, Yoshiyuki; Onozuka, Minoru

    2015-01-01

    Chewing is crushing food not only to aid swallowing and digestion, but also to help stress relief and regulate cognitive function, especially in attention. It is well known that chewing gum is used for sleepiness prevention during work, learning, and driving, suggesting a link between chewing and sustained attention. We hypothesized that chewing elevates attention and/or alertness, leading to improvements in cognitive performance. We carried out a systematic review of the PubMed database. We inspected the attributes of effects on attention in studies investigating the effects of chewing on attention or alertness conducted with pre-post design in healthy subjects, except elderly. We identified 151 references, 22 of which were included: 14 (64%) showed positive attributes of effects on attention, 1 (5%) showed negative attributes of effects on attention, 5 (23%) showed both positive and negative attributes of effects on attention, and 2 (9%) showed no significant attributes of effects on attention. Thus, positive attributes of effects of chewing on attention, especially on sustained attention, were shown in over half of the reports. These effects also appeared with improvement in mood and stress relief and were influenced by time-on-task effect. Further studies are needed, but chewing could be useful for modifying cognitive function.

  14. Social Image Captioning: Exploring Visual Attention and User Attention

    Directory of Open Access Journals (Sweden)

    Leiquan Wang

    2018-02-01

    Full Text Available Image captioning with a natural language has been an emerging trend. However, the social image, associated with a set of user-contributed tags, has been rarely investigated for a similar task. The user-contributed tags, which could reflect the user attention, have been neglected in conventional image captioning. Most existing image captioning models cannot be applied directly to social image captioning. In this work, a dual attention model is proposed for social image captioning by combining the visual attention and user attention simultaneously.Visual attention is used to compress a large mount of salient visual information, while user attention is applied to adjust the description of the social images with user-contributed tags. Experiments conducted on the Microsoft (MS COCO dataset demonstrate the superiority of the proposed method of dual attention.

  15. Sustained attentional states require distinct temporal involvement of the dorsal and ventral medial prefrontal cortex

    Directory of Open Access Journals (Sweden)

    Antonio Luchicchi

    2016-08-01

    Full Text Available Attending the sensory environment for cue detection is a cognitive operation that occurs on a time scale of seconds. The dorsal and ventral medial prefrontal cortex (mPFC contribute to separate aspects of attentional processing. Pyramidal neurons in different parts of the mPFC are active during cognitive behavior, yet whether this activity is causally underlying attentional processing is not known. We aimed to determine the precise temporal requirements for activation of the mPFC subregions during the seconds prior to cue detection. To test this, we used optogenetic silencing of dorsal or ventral mPFC pyramidal neurons at defined time windows during a sustained attentional state. We find that the requirement of ventral mPFC pyramidal neuron activity is strictly time-locked to stimulus detection. Inhibiting the ventral mPFC two seconds before or during cue presentation reduces response accuracy and hampers behavioral inhibition. The requirement for dorsal mPFC activity on the other hand is temporally more loosely related to a preparatory attentional state, and short lapses in pyramidal neuron activity in dorsal mPFC do not affect performance. This only occurs when the dorsal mPFC is inhibited during the entire preparatory period. Together, our results reveal that a dissociable temporal recruitment of ventral and dorsal mPFC is required during attentional processing.

  16. Sustained Attentional States Require Distinct Temporal Involvement of the Dorsal and Ventral Medial Prefrontal Cortex.

    Science.gov (United States)

    Luchicchi, Antonio; Mnie-Filali, Ouissame; Terra, Huub; Bruinsma, Bastiaan; de Kloet, Sybren F; Obermayer, Joshua; Heistek, Tim S; de Haan, Roel; de Kock, Christiaan P J; Deisseroth, Karl; Pattij, Tommy; Mansvelder, Huibert D

    2016-01-01

    Attending the sensory environment for cue detection is a cognitive operation that occurs on a time scale of seconds. The dorsal and ventral medial prefrontal cortex (mPFC) contribute to separate aspects of attentional processing. Pyramidal neurons in different parts of the mPFC are active during cognitive behavior, yet whether this activity is causally underlying attentional processing is not known. We aimed to determine the precise temporal requirements for activation of the mPFC subregions during the seconds prior to cue detection. To test this, we used optogenetic silencing of dorsal or ventral mPFC pyramidal neurons at defined time windows during a sustained attentional state. We find that the requirement of ventral mPFC pyramidal neuron activity is strictly time-locked to stimulus detection. Inhibiting the ventral mPFC 2 s before or during cue presentation reduces response accuracy and hampers behavioral inhibition. The requirement for dorsal mPFC activity on the other hand is temporally more loosely related to a preparatory attentional state, and short lapses in pyramidal neuron activity in dorsal mPFC do not affect performance. This only occurs when the dorsal mPFC is inhibited during the entire preparatory period. Together, our results reveal that a dissociable temporal recruitment of ventral and dorsal mPFC is required during attentional processing.

  17. Time-lapse imaging of primary preneoplastic mammary epithelial cells derived from genetically engineered mouse models of breast cancer.

    Science.gov (United States)

    Nakles, Rebecca E; Millman, Sarah L; Cabrera, M Carla; Johnson, Peter; Mueller, Susette; Hoppe, Philipp S; Schroeder, Timm; Furth, Priscilla A

    2013-02-08

    Time-lapse imaging can be used to compare behavior of cultured primary preneoplastic mammary epithelial cells derived from different genetically engineered mouse models of breast cancer. For example, time between cell divisions (cell lifetimes), apoptotic cell numbers, evolution of morphological changes, and mechanism of colony formation can be quantified and compared in cells carrying specific genetic lesions. Primary mammary epithelial cell cultures are generated from mammary glands without palpable tumor. Glands are carefully resected with clear separation from adjacent muscle, lymph nodes are removed, and single-cell suspensions of enriched mammary epithelial cells are generated by mincing mammary tissue followed by enzymatic dissociation and filtration. Single-cell suspensions are plated and placed directly under a microscope within an incubator chamber for live-cell imaging. Sixteen 650 μm x 700 μm fields in a 4x4 configuration from each well of a 6-well plate are imaged every 15 min for 5 days. Time-lapse images are examined directly to measure cellular behaviors that can include mechanism and frequency of cell colony formation within the first 24 hr of plating the cells (aggregation versus cell proliferation), incidence of apoptosis, and phasing of morphological changes. Single-cell tracking is used to generate cell fate maps for measurement of individual cell lifetimes and investigation of cell division patterns. Quantitative data are statistically analyzed to assess for significant differences in behavior correlated with specific genetic lesions.

  18. Fluorescence time-lapse imaging of single cells targeted with a focused scanning charged-particle microbeam

    Energy Technology Data Exchange (ETDEWEB)

    Bourret, Stéphane [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Vianna, François [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); IRSN, BP 3, F-13115 Saint-Paul Lez Durance (France); Devès, Guillaume [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Atallah, Vincent [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Department of Radiation Oncology, Institut Bergonié, Bordeaux (France); Univ. Victor Segalen, Bordeaux (France); Moretto, Philippe; Seznec, Hervé [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Barberet, Philippe, E-mail: barberet@cenbg.in2p3.fr [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France)

    2014-04-01

    Charged particle microbeams provide unique features to study targeted and non-targeted radiation response and have recently emerged as a powerful tool to investigate radiation-induced DNA damage and repair. We have developed a charged particle microbeam delivering protons and alpha particles in the MeV energy range equipped with online time-lapse imaging capabilities. The beam is focused to a sub-micrometer beam spot under vacuum by means of a triplet of magnetic quadrupoles and extracted in air through a 200 nm Si{sub 3}N{sub 4} window. The end-station is equipped with an automated fluorescence microscope used for single cell targeting and online time-lapse imaging. Cells are kept in their medium during the irradiation procedure and the sample temperature is regulated to 37 °C. An overall targeting accuracy of 2.0 ± 0.7 μm has been measured by tracking the re-localization of the XRCC1 protein. First measurements of this re-localization shows the ability of our system to follow online the radiation-induced re-localization of proteins in the first minutes after irradiation.

  19. Micromechanical Time-Lapse X-ray CT Study of Fatigue Damage in Uni-Directional Fibre Composites

    DEFF Research Database (Denmark)

    Jespersen, Kristine Munk; Lowe, Tristan; Withers, Philip J.

    2015-01-01

    . In the current study 3D X-ray Computed Tomography (XCT) is used to characterise the fatigue damage in the material at three different stages of the fatigue life of a tension-tension fatigue test. 3D XCT is performed on rectangular samples (4x4x110mm) cut out from pre-fatigued full-size fatigue test specimens......This study considers fatigue damage evolution in a uni-directional (UD) glass fibre composite used for wind turbine blades which is manufactured from a non-crimp fabric. It is the initial part of a time-lapse study where the damage progression is followed in a sample during a fatigue test....... The geometry of the cut-out is similar to that which will be used in the time-lapse study. As the micro-mechanical damage mechanisms are small features, it is necessary to obtain a high scan resolution which sets a limit to how large the field of view can be. Therefore, it is necessary to perform several scans...

  20. Lapse-time-dependent coda-wave depth sensitivity to local velocity perturbations in 3-D heterogeneous elastic media

    Science.gov (United States)

    Obermann, Anne; Planès, Thomas; Hadziioannou, Céline; Campillo, Michel

    2016-10-01

    In the context of seismic monitoring, recent studies made successful use of seismic coda waves to locate medium changes on the horizontal plane. Locating the depth of the changes, however, remains a challenge. In this paper, we use 3-D wavefield simulations to address two problems: first, we evaluate the contribution of surface- and body-wave sensitivity to a change at depth. We introduce a thin layer with a perturbed velocity at different depths and measure the apparent relative velocity changes due to this layer at different times in the coda and for different degrees of heterogeneity of the model. We show that the depth sensitivity can be modelled as a linear combination of body- and surface-wave sensitivity. The lapse-time-dependent sensitivity ratio of body waves and surface waves can be used to build 3-D sensitivity kernels for imaging purposes. Second, we compare the lapse-time behaviour in the presence of a perturbation in horizontal and vertical slabs to address, for instance, the origin of the velocity changes detected after large earthquakes.

  1. IP4DI: A software for time-lapse 2D/3D DC-resistivity and induced polarization tomography

    Science.gov (United States)

    Karaoulis, M.; Revil, A.; Tsourlos, P.; Werkema, D. D.; Minsley, B. J.

    2013-04-01

    We propose a 2D/3D forward modelling and inversion package to invert direct current (DC)-resistivity, time-domain induced polarization (TDIP), and frequency-domain induced polarization (FDIP) data. Each cell used for the discretization of the 2D/3D problems is characterized by a DC-resistivity value and a chargeability or complex conductivity for TDIP/FDIP problems, respectively. The governing elliptic partial differential equations are solved with the finite element method, which can be applied for both real and complex numbers. The inversion can be performed either for a single snapshot of data or for a sequence of snapshots in order to monitor a dynamic process such as a salt tracer test. For the time-lapse inversion, we have developed an active time constrained (ATC) approach that is very efficient in filtering out noise in the data that is not correlated over time. The forward algorithm is benchmarked with simple analytical solutions. The inversion package IP4DI is benchmarked with three tests, two including simple geometries. The last one corresponds to a time-lapse resistivity problem for cross-well tomography during enhanced oil recovery. The algorithms are based on MATLAB® code package and a graphical user interface (GUI).

  2. A surge of the glaciers Skobreen–Paulabreen, Svalbard, observed by time-lapse photographs and remote sensing data

    Directory of Open Access Journals (Sweden)

    Lene Kristensen

    2012-11-01

    Full Text Available We present observations of a surge of the glaciers Skobreen–Paulabreen, Svalbard, during 2003–05, including a time-lapse movie of the frontal advance during 2005, Advanced Spaceborne Thermal Emission (ASTER imagery and oblique aerial photographs. The surge initiated in Skobreen, and then propagated downglacier into the lower parts of Paulabreen. ASTER satellite images from different stages of the surge are used to evaluate the surge progression. Features on the glacier surface advanced 2800 m over 2.4 yr, averaging 3.2 m/day, while the front advanced less (ca. 1300 m due to contemporaneous calving. The surge resulted in a lateral displacement of the medial moraines of Paulabreen of ca. 600 m at the glacier front. The time-lapse movie captured the advance of the frontal part of the glacier, and dramatically illustrates glacier dynamic processes in an accessible way. The movie documents a range of processes such as a plug-like flow of the glacier, proglacial thrusting, incorporation of old, dead ice at the margin, and calving into the fjord. The movie provides a useful resource for researchers, educators seeking to teach and inspire students, and those wishing to communicate the fascination of glacier science to a wider public.

  3. Estimation of soil hydraulic parameters by integrated hydrogeophysical inversion of time-lapse GPR data measured at Selhausen, Germany

    KAUST Repository

    Jadoon, Khan

    2012-06-01

    We present an integrated hydrogeophysical inversion approach that uses time-lapse off-ground ground-penetrating radar (GPR) data to estimate soil hydraulic parameters, and apply it to a dataset collected in the field. Off-ground GPR data are mainly sensitive to the near-surface water content profile and dynamics, and are thus related to soil hydraulic parameters, such as the parameters of the hydraulic conductivity and water retention functions. The hydrological simulator HYDRUS 1-D was used with a two-layer single- and dual-porosity model. To monitor the soil water content dynamics, time-lapse GPR and time domain reflectometry (TDR) measurements were performed, whereby only GPR data was used in the inversion. The dual porosity model provided better results compared to the single porosity model for describing the soil water dynamics, which is supported by field observations of macropores. Furthermore, the GPR-derived water content profiles reconstructed from the integrated hydrogeophysical inversion were in good agreement with TDR observations. These results suggest that the proposed method is promising for non-invasive characterization of the shallow subsurface hydraulic properties and monitoring water dynamics at the field scale.

  4. Comparison of recommended sanctions for lapses in professionalism of undergraduate medical students in a Saudi Arabian and a Scottish medical school.

    Science.gov (United States)

    Sattar, Kamran; Roff, Sue

    2016-12-01

    Medical Professionalism is recognized as a cultural construct. We explore perceptions of the severity of lapses in professionalism of undergraduate medical students at two medical schools with different cultural contexts. Respondents from two medical schools (Saudi Arabia & UK) recommended sanctions for the first time, unmitigated lapses in academic professionalism, using the Dundee Polyprofessionalism Inventory 1: Academic Integrity. While more than two-thirds of the recommended sanctions for the 30 items of poor professionalism were fully or nearly congruent among the 1125 respondents, there were substantial differences in recommended response for one-third of the items, with a strong tendency for the Saudi students to recommend more lenient sanctions than the Scottish students. The strategy of using recommended sanctions as a proxy for the perception of the severity of different lapses in professionalism may be a useful tool in learning and teaching academic professionalism among medical students in different cultural contexts.

  5. Examining the information content of time-lapse crosshole GPR data collected under different infiltration conditions to estimate unsaturated soil hydraulic properties

    DEFF Research Database (Denmark)

    Scholer, M.; Irving, J.; Zibar, Majken Caroline Looms

    2013-01-01

    Time-lapse geophysical data acquired during transient hydrological experiments are being increasingly employed to estimate subsurface hydraulic properties at the field scale. In particular, crosshole ground-penetrating radar (GPR) data, collected while water infiltrates into the subsurface either...... by natural or artificial means, have been demonstrated in a number of studies to contain valuable information concerning the hydraulic properties of the unsaturated zone. Previous work in this domain has considered a variety of infiltration conditions and different amounts of time-lapse GPR data...... of time-lapse zero-offset-profile (ZOP) GPR traveltime data, collected under three different infiltration conditions, for the estimation of van Genuchten–Mualem (VGM) parameters in a layered subsurface medium. Specifically, we systematically analyze synthetic and field GPR data acquired under natural...

  6. Attentional accounting: Voluntary spatial attention increases budget category prioritization.

    Science.gov (United States)

    Mrkva, Kellen; Van Boven, Leaf

    2017-09-01

    Too often, people fail to prioritize the most important activities, life domains, and budget categories. One reason for misplaced priorities, we argue, is that activities and categories people have frequently or recently attended to seem higher priority than other activities and categories. In Experiment 1, participants were cued to direct voluntary spatial attention toward 1 side of a screen while images depicting different budget categories were presented: 1 category on the cued side and 1 on the noncued side of the screen. Participants rated cued budget categories as higher priority than noncued budget categories. Cued attention also increased perceived distinctiveness, and a mediation model was consistent with the hypothesis that distinctiveness mediates the effect of cued attention on prioritization. Experiment 2 orthogonally manipulated 2 components of a spatial cuing manipulation-heightened visual attention and heightened mental attention-to examine how each influences prioritization. Visual attention and mental attention additively increased prioritization. In Experiment 3, attention increased prioritization even when prioritization decisions were incentivized, and even when heightened attention was isolated from primacy and recency. Across experiments, cued categories were prioritized more than noncued categories even though measures were taken to disguise the purpose of the experiments and manipulate attention incidentally (i.e., as a by-product of an unrelated task). (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. More attention must be paid: the neurobiology of attentional effort.

    Science.gov (United States)

    Sarter, Martin; Gehring, William J; Kozak, Rouba

    2006-08-01

    Increases in attentional effort are defined as the motivated activation of attentional systems in response to detrimental challenges on attentional performance, such as the presentation of distractors, prolonged time-on-task, changing target stimulus characteristics and stimulus presentation parameters, circadian phase shifts, stress or sickness. Increases in attentional effort are motivated by the expected performance outcome; in the absence of such motivation, attentional performance continues to decline or may cease altogether. The beneficial effects of increased attentional effort are due in part to the activation of top-down mechanisms that act to optimize input detection and processing, thereby stabilizing or recovering attentional performance in response to challenges. Following a description of the psychological construct "attentional effort", evidence is reviewed indicating that increases in the activity of cortical cholinergic inputs represent a major component of the neuronal circuitry mediating increases in attentional effort. A neuronal model describes how error detection and reward loss, indicating declining performance, are integrated with motivational mechanisms on the basis of neuronal circuits between prefrontal/anterior cingulate and mesolimbic regions. The cortical cholinergic input system is activated by projections of mesolimbic structures to the basal forebrain cholinergic system. In prefrontal regions, increases in cholinergic activity are hypothesized to contribute to the activation of the anterior attention system and associated executive functions, particularly the top-down optimization of input processing in sensory regions. Moreover, and influenced in part by prefrontal projections to the basal forebrain, increases in cholinergic activity in sensory and other posterior cortical regions contribute directly to the modification of receptive field properties or the suppression of contextual information and, therefore, to the mediation of

  8. Assessment of Attention in Preschoolers

    Science.gov (United States)

    Mahone, E.M.; Schneider, H.E.

    2012-01-01

    In the past two decades, there has been an increased interest in the assessment and treatment of preschool children presenting with concerns about attention problems. This article reviews the research and clinical literature involving assessment of attention and related skills in the preschool years. While inattention among preschoolers is common, symptoms alone do not necessarily indicate a disorder, and most often represent a normal variation in typical preschool child development. Thus, accurate identification of “disordered” attention in preschoolers can be challenging, and development of appropriate, norm-referenced tests of attention for preschoolers is also difficult. The current review suggests that comprehensive assessment of attention and related functions in the preschool child should include thorough review of the child’s history, planned observations, and formal psychometric testing. The three primary methods of psychometric assessment that have been used to characterize attentional functioning in preschool children include performance-based tests, structured caregiver interviews, and rating scales (parent, teacher, and clinician). Among performance-based methods for measurement of attention in the preschool years, tests have been developed to assess sustained attention, selective (focused) attention, span of attention (encoding/manipulation), and (top-down) controlled attention—including freedom from distractibility and set shifting. Many of these tests remain experimental in nature, and review of published methods yields relatively few commercially available, nationally normed tests of attention for preschoolers, and an overall dearth of reliability and validity studies on the available measures. PMID:23090646

  9. Attention in a bayesian framework

    DEFF Research Database (Denmark)

    Whiteley, Louise Emma; Sahani, Maneesh

    2012-01-01

    The behavioral phenomena of sensory attention are thought to reflect the allocation of a limited processing resource, but there is little consensus on the nature of the resource or why it should be limited. Here we argue that a fundamental bottleneck emerges naturally within Bayesian models...... of perception, and use this observation to frame a new computational account of the need for, and action of, attention - unifying diverse attentional phenomena in a way that goes beyond previous inferential, probabilistic and Bayesian models. Attentional effects are most evident in cluttered environments......, and include both selective phenomena, where attention is invoked by cues that point to particular stimuli, and integrative phenomena, where attention is invoked dynamically by endogenous processing. However, most previous Bayesian accounts of attention have focused on describing relatively simple experimental...

  10. Cognitive maps and attention.

    Science.gov (United States)

    Hardt, Oliver; Nadel, Lynn

    2009-01-01

    Cognitive map theory suggested that exploring an environment and attending to a stimulus should lead to its integration into an allocentric environmental representation. We here report that directed attention in the form of exploration serves to gather information needed to determine an optimal spatial strategy, given task demands and characteristics of the environment. Attended environmental features may integrate into spatial representations if they meet the requirements of the optimal spatial strategy: when learning involves a cognitive mapping strategy, cues with high codability (e.g., concrete objects) will be incorporated into a map, but cues with low codability (e.g., abstract paintings) will not. However, instructions encouraging map learning can lead to the incorporation of cues with low codability. On the other hand, if spatial learning is not map-based, abstract cues can and will be used to encode locations. Since exploration appears to determine what strategy to apply and whether or not to encode a cue, recognition memory for environmental features is independent of whether or not a cue is part of a spatial representation. In fact, when abstract cues were used in a way that was not map-based, or when they were not used for spatial navigation at all, they were nevertheless recognized as familiar. Thus, the relation between exploratory activity on the one hand and spatial strategy and memory on the other appears more complex than initially suggested by cognitive map theory.

  11. [Attention deficit hyperactivity disorder].

    Science.gov (United States)

    Cunill, Ruth; Castells, Xavier

    2015-04-20

    Attention deficit hyperactivity disorder (ADHD) is one of the most common childhood psychiatric disorders and can persist into the adulthood. ADHD has important social, academic and occupational consequences. ADHD diagnosis is based on the fulfillment of several clinical criteria, which can vary depending on the diagnostic system used. The clinical presentation can show great between-patient variability and it has been related to a dysfunction in the fronto-striatal and meso-limbic circuits. Recent investigations support a model in which multiple genetic and environmental factors interact to create a neurobiological susceptibility to develop the disorder. However, no clear causal association has yet been identified. Although multimodal treatment including both pharmacological and psychosocial interventions is usually recommended, no convincing evidence exists to support this recommendation. Pharmacological treatment has fundamentally shown to improve ADHD symptoms in the short term, while efficacy data for psychosocial interventions are scarce and inconsistent. Yet, drug treatment is increasingly popular and the last 2 decades have witnessed a sharp increase in the prescription of anti-ADHD medications coinciding with the marketing of new drugs to treat ADHD. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  12. Intense dust episodes in the Mediterranean and possible effects on atmospheric lapse rates

    Science.gov (United States)

    Hatzianastassiou, Nikos; Gkikas, Antonis; Papadimas, Christos D.; Gavrouzou, Maria

    2016-04-01

    Dust aerosols are major contributor to the atmospheric particulate matter, having significant effects on climate and weather patterns as well as on human health, not to mention others like agriculture or ocean chlorophyll. Moreover, these effects are maximized under conditions of massive dust concentration in the atmosphere, namely dust episodes or events. Such events are caused by uplifting and transport of dust from arid and semi-arid areas under favorable synoptic conditions. The Mediterranean basin, nearby to the greatest world deserts of North Africa and Middle East, frequently undergoes dust episodes. During such Mediterranean episodes, the number and mass concentration of dust is high, due to the proximity of its source areas. The dust episodes, through the direct interaction of dust primarily withthe shortwave but also with longwave radiation can lead to strong local warming in the atmosphere, possibly causing temperature inversion during daytime. The existence of such temperature inversions, associated with intense dust episodes in the Mediterranean, is the focus in this study. The methodology followed to achieve the scientific goal of the study consists in the use of a synergy of different data. This synergy enables: (i) the determination of intense dust episodes over the Mediterranean, (ii) the investigation and specification of temperature lapse rates and inversions during the days of dust episodes and (iii) the identification of vertical distribution of aerosols in the atmosphere over specific locations during the days of the episodes. These objectives are achieved through the use of data from: (i) the AERosol Robotic NETwork (AERONET) network, (ii) the Upper Air Observations (radiosondes) database of the University of Wyoming (UoW) and (iii) the European Aerosol Research Lidar Network (EARLINET) database. The study period spans the years from 2000 to 2013, constrained by the data availability of the databases. A key element of the methodology is the

  13. Visual attention: The past 25 years

    National Research Council Canada - National Science Library

    Carrasco, Marisa

    2011-01-01

    This review focuses on covert attention and how it alters early vision. I explain why attention is considered a selective process, the constructs of covert attention, spatial endogenous and exogenous attention, and feature-based attention...

  14. Chewing and Attention: A Positive Effect on Sustained Attention

    OpenAIRE

    Yoshiyuki Hirano; Minoru Onozuka

    2015-01-01

    Chewing is crushing food not only to aid swallowing and digestion, but also to help stress relief and regulate cognitive function, especially in attention. It is well known that chewing gum is used for sleepiness prevention during work, learning, and driving, suggesting a link between chewing and sustained attention. We hypothesized that chewing elevates attention and/or alertness, leading to improvements in cognitive performance. We carried out a systematic review of the PubMed database. We ...

  15. Confident failures: Lapses of working memory reveal a metacognitive blind spot.

    Science.gov (United States)

    Adam, Kirsten C S; Vogel, Edward K

    2017-07-01

    Working memory performance fluctuates dramatically from trial to trial. On many trials, performance is no better than chance. Here, we assessed participants' awareness of working memory failures. We used a whole-report visual working memory task to quantify both trial-by-trial performance and trial-by-trial subjective ratings of inattention to the task. In Experiment 1 (N = 41), participants were probed for task-unrelated thoughts immediately following 20% of trials. In Experiment 2 (N = 30), participants gave a rating of their attentional state following 25% of trials. Finally, in Experiments 3a (N = 44) and 3b (N = 34), participants reported confidence of every response using a simple mouse-click judgment. Attention-state ratings and off-task thoughts predicted the number of items correctly identified on each trial, replicating previous findings that subjective measures of attention state predict working memory performance. However, participants correctly identified failures on only around 28% of failure trials. Across experiments, participants' metacognitive judgments reliably predicted variation in working memory performance but consistently and severely underestimated the extent of failures. Further, individual differences in metacognitive accuracy correlated with overall working memory performance, suggesting that metacognitive monitoring may be key to working memory success.

  16. Attentional capture and engagement during the attentional blink: A "camera" metaphor of attention.

    Science.gov (United States)

    Zivony, Alon; Lamy, Dominique

    2016-11-01

    Identification of a target is impaired when it follows a previous target within 500 ms, suggesting that our attentional system suffers from severe temporal limitations. Although control-disruption theories posit that such impairment, known as the attentional blink (AB), reflects a difficulty in matching incoming information with the current attentional set, disrupted-engagement theories propose that it reflects a delay in later processes leading to transient enhancement of potential targets. Here, we used a variant of the contingent-capture rapid serial visual presentation (RSVP) paradigm (Folk, Ester, & Troemel, 2009) to adjudicate these competing accounts. Our results show that a salient distractor that shares the target color captures attention to the same extent whether it appears within or outside the blink, thereby invalidating the notion that control over the attentional set is compromised during the blink. In addition, our results show that during the blink, not the attention-capturing object itself but the item immediately following it, is selected, indicating that the AB manifests as a delay between attentional capture and attentional engagement. We therefore conclude that attentional capture and attentional engagement can be dissociated as separate stages of attentional selection. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  17. A predictive model for blastocyst formation based on morphokinetic parameters in time-lapse monitoring of embryo development.

    Science.gov (United States)

    Milewski, Robert; Kuć, Paweł; Kuczyńska, Agnieszka; Stankiewicz, Bożena; Łukaszuk, Krzysztof; Kuczyński, Waldemar

    2015-04-01

    The aim of the study was to create a predictive model of blastocyst development based on morphokinetic parameters of time-lapse embryoscope monitoring. Time-lapse recordings of 432 embryos (obtained from 77 patients), monitored in Embryoscope, were involved in the study. Patients underwent in vitro fertilization according to standard procedure between June 2012 and April 2013. A retrospective analysis of morphokinetic features, focused on duration of time from the Intracytoplasmic Sperm Injection (ICSI) procedure to consecutive embryo division for 2, 3, 4 and 5 blastomeres, as well as time intervals between each division, was conducted. All embryos were observed for 5 days. Based on the distribution of analyzed morphokinetic parameters and number of embryos developed to blastocyst, a range denoting the possibility of an embryo reaching blastocyst stage was determined. According to the obtained results, univariate and multivariate logistic regression analyses were performed. Based on the times of division for two and five blastomeres and intervals between the second and third division, a multivariate predictive model was created. The predictive equation was constructed based on the parameters of logistic regression analysis (odds ratios). Statistically significant differences (p prediction parameter between the group of embryos developed to blastocyst (the median value: Me = 9.95, and quartiles: Q1 = 7.59, Q3 = 12.30) and embryos that did not develop to the blastocyst stage (Me = 4.66, Q1 = 2.33, Q3 = 8.19) were found. A Receiver Operating Characteristic (ROC) curve was created for the constructed predictive model. The Area Under the Curve was AUC = 0.806 with a 95 % confidence interval (0.747, 0.864). The predictive model constructed in this study has been validated using an independent data set, which indicates that the model is reliable and repeatable. Time-lapse imaging presents a new diagnostic tool for parametric evaluation of

  18. Entropy-Bayesian Inversion of Time-Lapse Tomographic GPR data for Monitoring Dielectric Permittivity and Soil Moisture Variations

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Z; Terry, N; Hubbard, S S; Csatho, B

    2013-02-12

    In this study, we evaluate the possibility of monitoring soil moisture variation using tomographic ground penetrating radar travel time data through Bayesian inversion, which is integrated with entropy memory function and pilot point concepts, as well as efficient sampling approaches. It is critical to accurately estimate soil moisture content and variations in vadose zone studies. Many studies have illustrated the promise and value of GPR tomographic data for estimating soil moisture and associated changes, however, challenges still exist in the inversion of GPR tomographic data in a manner that quantifies input and predictive uncertainty, incorporates multiple data types, handles non-uniqueness and nonlinearity, and honors time-lapse tomograms collected in a series. To address these challenges, we develop a minimum relative entropy (MRE)-Bayesian based inverse modeling framework that non-subjectively defines prior probabilities, incorporates information from multiple sources, and quantifies uncertainty. The framework enables us to estimate dielectric permittivity at pilot point locations distributed within the tomogram, as well as the spatial correlation range. In the inversion framework, MRE is first used to derive prior probability distribution functions (pdfs) of dielectric permittivity based on prior information obtained from a straight-ray GPR inversion. The probability distributions are then sampled using a Quasi-Monte Carlo (QMC) approach, and the sample sets provide inputs to a sequential Gaussian simulation (SGSim) algorithm that constructs a highly resolved permittivity/velocity field for evaluation with a curved-ray GPR forward model. The likelihood functions are computed as a function of misfits, and posterior pdfs are constructed using a Gaussian kernel. Inversion of subsequent time-lapse datasets combines the Bayesian estimates from the previous inversion (as a memory function) with new data. The memory function and pilot point design takes

  19. Entropy-Bayesian Inversion of Time-Lapse Tomographic GPR data for Monitoring Dielectric Permittivity and Soil Moisture Variations

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Zhangshuan; Terry, Neil C.; Hubbard, Susan S.

    2013-02-22

    In this study, we evaluate the possibility of monitoring soil moisture variation using tomographic ground penetrating radar travel time data through Bayesian inversion, which is integrated with entropy memory function and pilot point concepts, as well as efficient sampling approaches. It is critical to accurately estimate soil moisture content and variations in vadose zone studies. Many studies have illustrated the promise and value of GPR tomographic data for estimating soil moisture and associated changes, however, challenges still exist in the inversion of GPR tomographic data in a manner that quantifies input and predictive uncertainty, incorporates multiple data types, handles non-uniqueness and nonlinearity, and honors time-lapse tomograms collected in a series. To address these challenges, we develop a minimum relative entropy (MRE)-Bayesian based inverse modeling framework that non-subjectively defines prior probabilities, incorporates information from multiple sources, and quantifies uncertainty. The framework enables us to estimate dielectric permittivity at pilot point locations distributed within the tomogram, as well as the spatial correlation range. In the inversion framework, MRE is first used to derive prior probability density functions (pdfs) of dielectric permittivity based on prior information obtained from a straight-ray GPR inversion. The probability distributions are then sampled using a Quasi-Monte Carlo (QMC) approach, and the sample sets provide inputs to a sequential Gaussian simulation (SGSIM) algorithm that constructs a highly resolved permittivity/velocity field for evaluation with a curved-ray GPR forward model. The likelihood functions are computed as a function of misfits, and posterior pdfs are constructed using a Gaussian kernel. Inversion of subsequent time-lapse datasets combines the Bayesian estimates from the previous inversion (as a memory function) with new data. The memory function and pilot point design takes advantage of

  20. Evaluation and localization of an artificial drainage network by 3D time-lapse electrical resistivity tomography.

    Science.gov (United States)

    Jouen, T; Clément, R; Henine, H; Chaumont, C; Vincent, B; Tournebize, J

    2016-08-26

    In France, 10 % of total arable land is equipped with subsurface drainage systems, to control winter and spring waterlogging due to a temporary perched water table. Most of these systems were installed in the1980s and have aged since then and may now need maintenance. Sometimes, the location of the systems is known, but the standard situation in France is that the original as-built master sketches are no longer available. Performance assessment of drainage systems and curative actions are complicated since drain location is unknown. In this article, the authors test the application of a non-destructive drain detection method which consists in water injection at the outfall of the drainage network combined with time-lapse electrical resistivity tomography (ERT) monitoring. To assess the performance of this methodology, which consists in measuring electrical resistivity from electrodes placed at the nodes of a 1.2-m regular mesh, the authors interpreted the signal using a two-step approach. The first step is based on 3D ERT numerical modelling during a scenario of surface infiltration processes (forward modelling followed by geophysical inversion); this step optimizes the ERT method for locating the infiltration at depths below 1 m. The second step is the validation of the results obtained by numerical modelling with an experimental data set, using water injection into the drainage network combined with time-lapse ERT monitoring on an experimental field site. The results showed the relevance of time-lapse ERT monitoring on a small agricultural plot for locating the drainage network. The numerical results also showed several limitations of the combined methodology: (i) it is necessary to use an electrode spacing unit less than 1.20 m, which does not facilitate investigation on large agriculture plots, (ii) measurements must be taken when resistivity contrast is the strongest between the infiltration area and the soil and (iii) the volume of water needed for

  1. Highlights from the SoilCAM project: Soil Contamination, Advanced integrated characterisation and time-lapse Monitoring

    Science.gov (United States)

    French, H. K.; van der Zee, S. E. A. T. M.; Wehrer, M.; Godio, A.; Pedersen, L. B.; Toscano, G.

    2012-04-01

    The SoilCAM project (Soil Contamination, Advanced integrated characterisation and time-lapse Monitoring 2008-2012, EU-FP7-212663) is aimed at improving current methods for monitoring contaminant distribution and biodegradation in the subsurface. At two test sites, Oslo airport Gardermoen in Norway and the Trecate site in Italy, a number of geophysical techniques, lysimeter and other soil and water sampling techniques as well as numerical flow and transport modelling have been combined at different scales in order to characterise flow transport processes in the unsaturated and saturated zones. Laboratory experiments have provided data on physical and bio-geo-chemical parameters for use in models and to select remediation methods. The geophysical techniques were used to map geological heterogeneities and also conduct time-lapse measurements of processes in the unsaturated zone. Both cross borehole and surface electrodes were used for electrical resistivity and induced polarisation surveys. The geophysical surveys showed clear indications of areas highly affected by de-icing chemicals along the runway at Oslo airport. The time lapse measurements along the runway at the airport show infiltration patterns during snowmelt and are used to validate 2D unsaturated flow and transport simulations using SUTRA. The Orchestra model is used to describe the complex interaction between bio-geo-chemical processes in a 1D profile along the runway. The presence of installations such as a membrane along the runway highly affects the flow pattern and challenges the capacity of the numerical code. Smaller scale field site measurements have revealed the increase of iron and manganese during degradation of de-icing chemicals. The use of Nitrate to increase red-ox potential was tested, but results have not been analysed yet. So far it cannot be concluded that degradation process can be quantified indirectly by geophysical monitoring. At the Trecate site a combination of georadar, electrical

  2. Separating climate change signals into thermodynamic, lapse-rate and circulation effects: theory and application to the European summer climate

    Science.gov (United States)

    Kröner, Nico; Kotlarski, Sven; Fischer, Erich; Lüthi, Daniel; Zubler, Elias; Schär, Christoph

    2017-05-01

    Climate models robustly project a strong overall summer warming across Europe showing a characteristic north-south gradient with enhanced warming and drying in southern Europe. However, the processes that are responsible for this pattern are not fully understood. We here employ an extended surrogate or pseudo-warming approach to disentangle the contribution of different mechanisms to this response pattern. The basic idea of the surrogate technique is to use a regional climate model and apply a large-scale warming to the lateral boundary conditions of a present-day reference simulation, while maintaining the relative humidity (and thus implicitly increasing the specific moisture content). In comparison to previous studies, our approach includes two important extensions: first, different vertical warming profiles are applied in order to separate the effects of a mean warming from lapse-rate effects. Second, a twin-design is used, in which the climate change signals are not only added to present-day conditions, but also subtracted from a scenario experiment. We demonstrate that these extensions provide an elegant way to separate the full climate change signal into contributions from large-scale thermodynamic (TD), lapse-rate (LR), and circulation and other remaining effects (CO). The latter in particular include changes in land-ocean contrast and spatial variations of the SST warming patterns. We find that the TD effect yields a large-scale warming across Europe with no distinct latitudinal gradient. The LR effect, which is quantified for the first time in our study, leads to a stronger warming and some drying in southern Europe. It explains about 50 % of the warming amplification over the Iberian Peninsula, thus demonstrating the important role of lapse-rate changes. The effect is linked to an extending Hadley circulation. The CO effect as inherited from the driving GCM is shown to further amplify the north-south temperature change gradient. In terms of mean summer

  3. Time-lapse seismic modeling and production data assimilation for enhanced oil recovery and carbon dioxide sequestration

    Science.gov (United States)

    Kumar, Ajitabh

    Production from a hydrocarbon reservoir is typically supported by water or carbon dioxide (CO2) injection. CO2 injection into hydrocarbon reservoirs is also a promising solution for reducing environmental hazards from the release of green house gases into the earth's atmosphere. Numerical simulators are used for designing and predicting the complex behavior of systems under such scenarios. Two key steps in such studies are forward modeling for performance prediction based on simulation studies using reservoir models and inverse modeling for updating reservoir models using the data collected from field. The viability of time-lapse seismic monitoring using an integrated modeling of fluid flow, including chemical reactions, and seismic response is examined. A comprehensive simulation of the gas injection process accounting for the phase behavior of CO2-reservoir fluids, the associated precipitation/dissolution reactions, and the accompanying changes in porosity and permeability is performed. The simulation results are then used to model the changes in seismic response with time. The general observation is that gas injection decreases bulk density and wave velocity of the host rock system. Another key topic covered in this work is the data assimilation study for hydrocarbon reservoirs using Ensemble Kalman Filter (EnKF). Some critical issues related to EnKF based history matching are explored, primarily for a large field with substantial production history. A novel and efficient approach based on spectral clustering to select 'optimal' initial ensemble members is proposed. Also, well-specific black-oil or compositional streamline trajectories are used for covariance localization. Approach is applied to the Weyburn field, a large carbonate reservoir in Canada. The approach for optimal member selection is found to be effective in reducing the ensemble size which was critical for this large-scale field application. Streamline-based covariance localization is shown to play

  4. Modeling of time-lapse seismic reflection data from CO2 sequestration at West Pearl Queen Field

    Science.gov (United States)

    Bartel, L. C.; Haney, M. M.; Aldridge, D. F.; Symons, N. P.; Elbring, G. J.

    2006-12-01

    Sequestration of CO2 in depleted oil reservoirs, saline aquifers, or unminable coal sequences may prove to be an economical and environmentally safe means for long-term removal of carbon from the atmosphere. Requirements for storage of CO2 in subsurface geologic repositories (e.g., less than 0.1% per year leakage) pose significant challenges for geophysical remote sensing techniques. The many issues relevant to successful CO2 sequestration (volume in place, migration, leakage rate) require improved understanding of the advantages and pitfalls of potential monitoring methods. Advanced numerical modeling of time-lapse seismic reflection responses offers a controlled environment for testing hypotheses and exploring alternatives. The U.S. Department of Energy has conducted CO2 sequestration and monitoring tests at West Pearl Queen (WPQ) field in southeastern New Mexico. High-quality 9C/3D seismic reflection data were acquired before and after injection of ~2 kt of CO2 into a depleted sandstone unit at ~4200 ft depth. Images developed from time- lapse seismic data appear to reveal strong reflectivity changes attributed to displacement of brine by CO2. We are pursuing seismic numerical modeling studies with the goal of understanding and assessing the reliability and robustness of the time-lapse reflection responses. A 3D time-domain finite-difference isotropic elastic wave propagation algorithm generates realistic synthetic data. With this capability, we examine how various types of errors and noise in the 4D data degrade the ability to image a deep CO2 plume. Source/receiver sampling, subsurface illumination, correlated geologic heterogeneity, and static shifts are considered. As a result, we are able to make quantitative estimates of the tolerable errors for monitoring CO2 injection at WPQ field. Future plans include incorporating 3D poroelastic wave propagation modeling into the analysis. Sandia National Laboratories is a multiprogram science and engineering facility

  5. Social modulators of social attention

    OpenAIRE

    Dalmaso, Mario

    2014-01-01

    Social attention refers to the ability, which generally characterizes human beings as well as other animal species, to orient attentional resources in response to spatial cues provided by other individuals. These spatial cues are typically represented by gaze direction, head direction, and body orientation. This thesis focused mainly on the role that some social variables play in modulating this ability. In Chapter 1, the concept of social attention and its relevance in regulating social i...

  6. Attention, Media, Value and Economics

    OpenAIRE

    Aigrain, Philippe

    1997-01-01

    Building on the debate about the "attention economy" initiated by Michael Goldhaber and Rishab Aiyer Ghosh, I introduce the notion of valuing process, i.e. the process by which potential value can be translated in an economy. I show that the valuing processes applicable to attention depend on the nature of the media through which attention can be given and looked for. From there, I claim that the integration between attention and action, and the creation of a related literacy are the keys to ...

  7. Preparatory attention in visual cortex.

    Science.gov (United States)

    Battistoni, Elisa; Stein, Timo; Peelen, Marius V

    2017-05-01

    Top-down attention is the mechanism that allows us to selectively process goal-relevant aspects of a scene while ignoring irrelevant aspects. A large body of research has characterized the effects of attention on neural activity evoked by a visual stimulus. However, attention also includes a preparatory phase before stimulus onset in which the attended dimension is internally represented. Here, we review neurophysiological, functional magnetic resonance imaging, magnetoencephalography, electroencephalography, and transcranial magnetic stimulation (TMS) studies investigating the neural basis of preparatory attention, both when attention is directed to a location in space and when it is directed to nonspatial stimulus attributes (content-based attention) ranging from low-level features to object categories. Results show that both spatial and content-based attention lead to increased baseline activity in neural populations that selectively code for the attended attribute. TMS studies provide evidence that this preparatory activity is causally related to subsequent attentional selection and behavioral performance. Attention thus acts by preactivating selective neurons in the visual cortex before stimulus onset. This appears to be a general mechanism that can operate on multiple levels of representation. We discuss the functional relevance of this mechanism, its limitations, and its relation to working memory, imagery, and expectation. We conclude by outlining open questions and future directions. © 2017 New York Academy of Sciences.

  8. Training attentional control in infancy

    National Research Council Canada - National Science Library

    Wass, Sam; Porayska-Pomsta, Kaska; Johnson, Mark H

    2011-01-01

    .... Relative to an active control group, and following only a relatively short training period, posttraining assessments revealed improvements in cognitive control and sustained attention, reduced...

  9. Attentional networks in developmental dyscalculia

    Directory of Open Access Journals (Sweden)

    Henik Avishai

    2010-01-01

    Full Text Available Abstract Background Very little is known about attention deficits in developmental dyscalculia, hence, this study was designed to provide the missing information. We examined attention abilities of participants suffering from developmental dyscalculia using the attention networks test - interactions. This test was designed to examine three different attention networks--executive function, orienting and alerting--and the interactions between them. Methods Fourteen university students that were diagnosed as suffering from developmental dyscalculia--intelligence and reading abilities in the normal range and no indication of attention-deficit hyperactivity disorder--and 14 matched controls were tested using the attention networks test - interactions. All participants were given preliminary tests to measure mathematical abilities, reading, attention and intelligence. Results The results revealed deficits in the alerting network--a larger alerting effect--and in the executive function networks--a larger congruity effect in developmental dyscalculia participants. The interaction between the alerting and executive function networks was also modulated by group. In addition, developmental dyscalculia participants were slower to respond in the non-cued conditions. Conclusions These results imply specific attentional deficits in pure developmental dyscalculia. Namely, those with developmental dyscalculia seem to be deficient in the executive function and alertness networks. They suffer from difficulty in recruiting attention, in addition to the deficits in numerical processing.

  10. Attentional networks in developmental dyscalculia.

    Science.gov (United States)

    Askenazi, Sarit; Henik, Avishai

    2010-01-07

    Very little is known about attention deficits in developmental dyscalculia, hence, this study was designed to provide the missing information. We examined attention abilities of participants suffering from developmental dyscalculia using the attention networks test - interactions. This test was designed to examine three different attention networks--executive function, orienting and alerting--and the interactions between them. Fourteen university students that were diagnosed as suffering from developmental dyscalculia--intelligence and reading abilities in the normal range and no indication of attention-deficit hyperactivity disorder--and 14 matched controls were tested using the attention networks test-interactions. All participants were given preliminary tests to measure mathematical abilities, reading, attention and intelligence. The results revealed deficits in the alerting network--a larger alerting effect--and in the executive function networks--a larger congruity effect in developmental dyscalculia participants. The interaction between the alerting and executive function networks was also modulated by group. In addition, developmental dyscalculia participants were slower to respond in the non-cued conditions. These results imply specific attentional deficits in pure developmental dyscalculia. Namely, those with developmental dyscalculia seem to be deficient in the executive function and alertness networks. They suffer from difficulty in recruiting attention, in addition to the deficits in numerical processing.

  11. Paying Attention to Attention: New Economies for Learning

    Science.gov (United States)

    de Castell, Suzanne; Jenson, Jennifer

    2004-01-01

    Challenging formal education's traditional monopoly over the mass-scale acculturation of youth, the technological infrastructure of the new economy brings in its wake a new attentional economy in which any connected adult or child owns and controls a full economic share of her or his own attention. For youth who have never known the text-bound…

  12. Visual attention: The past 25 years

    OpenAIRE

    Carrasco, Marisa

    2011-01-01

    This review focuses on covert attention and how it alters early vision. I explain why attention is considered a selective process, the constructs of covert attention, spatial endogenous and exogenous attention, and feature-based attention. I explain how in the last 25 years research on attention has characterized the effects of covert attention on spatial filters and how attention influences the selection of stimuli of interest. This review includes the effects of spatial attention on discrim...

  13. Time-lapse systems for embryo incubation and assessment in assisted reproduction.

    Science.gov (United States)

    Armstrong, Sarah; Arroll, Nicola; Cree, Lynsey M; Jordan, Vanessa; Farquhar, Cindy

    2015-02-27

    Embryo incubation and assessment is a vital step in assisted reproductive technology (ART). Traditionally, embryo assessment has been achieved by removing embryos from a conventional incubator daily for assessment of quality by an embryologist, under a light microscope. Over recent years time-lapse systems (TLSs) have been developed which can take digital images of embryos at frequent time intervals. This allows embryologists, with or without the assistance of computer algorithms, to assess the quality of the embryos without physically removing them from the incubator.The potential advantages of a TLS include the ability to maintain a stable culture environment, therefore limiting the exposure of embryos to changes in gas composition, temperature and movement. Additionally a TLS has the potential advantage of improving embryo selection for ART treatment by utilising additional information gained through monitoring embryo development. To determine the effect of a TLS compared to conventional embryo incubation and assessment on clinical outcomes in couples undergoing ART. A comprehensive search of all the major electronic databases, including grey literature, was undertaken in co-ordination with the Trials Search Co-ordinator of the Cochrane Menstrual Disorders and Subfertility Group in July 2014 and repeated in November 2014 to confirm that the review is up to date. Two authors (SA and NA) independently scanned the titles and abstracts of the articles retrieved by the search. Full texts of potentially eligible randomised controlled trials (RCTs) were obtained and examined independently by the authors for their suitability according to the review inclusion criteria. In the case of doubt between the two authors, a third author (LC) was consulted to gain consensus. The selection process is documented with a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow chart. Data were obtained and extracted by two authors. Disagreement was resolved

  14. Acquiring fluorescence time-lapse movies of budding yeast and analyzing single-cell dynamics using GRAFTS.

    Science.gov (United States)

    Zopf, Christopher J; Maheshri, Narendra

    2013-07-18

    Fluorescence time-lapse microscopy has become a powerful tool in the study of many biological processes at the single-cell level. In particular, movies depicting the temporal dependence of gene expression provide insight into the dynamics of its regulation; however, there are many technical challenges to obtaining and analyzing fluorescence movies of single cells. We describe here a simple protocol using a commercially available microfluidic culture device to generate such data, and a MATLAB-based, graphical user interface (GUI) -based software package to quantify the fluorescence images. The software segments and tracks cells, enables the user to visually curate errors in the data, and automatically assigns lineage and division times. The GUI further analyzes the time series to produce whole cell traces as well as their first and second time derivatives. While the software was designed for S. cerevisiae, its modularity and versatility should allow it to serve as a platform for studying other cell types with few modifications.

  15. Isoniazid Killing of Mycobacterium smegmatis NADH Pyrophosphatase Mutant at Single-Cell Level using Microfluidics and Time-Lapse Microscopy.

    Science.gov (United States)

    Elitas, Meltem

    2017-09-07

    We introduce single-cell analysis for isoniazid-treated Mycobacterium smegmatis mutant, msm1946-NADH pyrophosphatase, using microfluidics and automated time-lapse microscopy. Mycobacterial NADH pyrophosphatase isoforms play an important role for the mechanism of isoniazid and ethionamide activation. Our single-cell analysis revealed important insights on isoniazid killing mechanism that was masked by traditional killing assays, raised significant questions related to viable but non-culturable subpopulation of cells, and existing methods that defines minimum inhibitory concentration of drugs. The major goal of this study was quantitatively analyze bacterial cell parameters to obtain high-resolution data for the time evolution of antibiotic killing at the single-cell level. The presented tools and methods could be applied to the closely related organisms to provide more detailed information for the design and employment of antibiotic treatments.

  16. Differentiation of human neural progenitor cell-derived spiral ganglion-like neurons: a time-lapse video study.

    Science.gov (United States)

    Edin, Fredrik; Liu, Wei; Boström, Marja; Magnusson, Peetra U; Rask-Andersen, Helge

    2014-05-01

    Human neural progenitor cells can differentiate into spiral ganglion-like cells when exposed to inner ear-associated growth factors. The phenotype bears resemblance to human sphere-derived neurons. To establish an in vitro model for the human auditory nerve to replace and complement in vivo animal experiments and ultimately human in vivo transplantation. Human neural progenitors were differentiated under conditions developed for in vitro survival of human primary spiral ganglion culture with media containing growth factors associated with inner ear development. Differentiation was documented using time-lapse video microscopy. Time-dependent marker expression was evaluated using immunocytochemistry with fluorescence and laser confocal microscopy. Within 14 days of differentiation, neural progenitors adopted neural phenotype and expressed spiral ganglion-associated markers.

  17. Remote estimation of the hydraulic properties of a sand using full-waveform integrated hydrogeophysical inversion of time-lapse, off-ground GPR data

    NARCIS (Netherlands)

    Lambot, S.; Slob, E.; Rhebergen, J.B.; Lopera, O.; Jadoon, K.Z.; Vereecken, H.

    2009-01-01

    We used integrated hydrogeophysical inversion of time-lapse, proximal ground penetrating radar (GPR) data to remotely infer the unsaturated soil hydraulic properties of a laboratory sand during an infiltration event. The inversion procedure involved full-waveform modeling of the radar signal and

  18. Monitoring channel head erosion processes in response to an artificially induced abrupt base level change using time-lapse photography 2301

    Science.gov (United States)

    Headcut and channel extension in response to an abrupt base level change in 2004 of approximately 1m was studied in a 1.29 ha semiarid headwater drainage on the Walnut Gulch Experimental Watershed (WGEW) in southeastern Arizona, USA. Field observations and time-lapse photography were coupled with hy...

  19. OPTICAL FLOW APPLIED TO TIME-LAPSE IMAGE SERIES TO ESTIMATE GLACIER MOTION IN THE SOUTHERN PATAGONIA ICE FIELD

    Directory of Open Access Journals (Sweden)

    E. Lannutti

    2016-06-01

    Full Text Available In this work, we assessed the feasibility of using optical flow to obtain the motion estimation of a glacier. In general, former investigations used to detect glacier changes involve solutions that require repeated observations which are many times based on extensive field work. Taking into account glaciers are usually located in geographically complex and hard to access areas, deploying time-lapse imaging sensors, optical flow may provide an efficient solution at good spatial and temporal resolution to describe mass motion. Several studies in computer vision and image processing community have used this method to detect large displacements. Therefore, we carried out a test of the proposed Large Displacement Optical Flow method at the Viedma Glacier, located at South Patagonia Icefield, Argentina. We collected monoscopic terrestrial time-lapse imagery, acquired by a calibrated camera at every 24 hour from April 2014 until April 2015. A filter based on temporal correlation and RGB color discretization between the images was applied to minimize errors related to changes in lighting, shadows, clouds and snow. This selection allowed discarding images that do not follow a sequence of similarity. Our results show a flow field in the direction of the glacier movement with acceleration in the terminus. We analyzed the errors between image pairs, and the matching generally appears to be adequate, although some areas show random gross errors related to the presence of changes in lighting. The proposed technique allowed the determination of glacier motion during one year, providing accurate and reliable motion data for subsequent analysis.

  20. Time-Lapse Micro-Tomography Measurements and Determination of Effective Transport Properties of Snow Metamorphism Under Advective Conditions

    Science.gov (United States)

    Ebner, P. P.; Grimm, S.; Steen-Larsen, H. C.; Schneebeli, M.; Steinfeld, A.

    2014-12-01

    The metamorphism of snow under advective air flow, with and without temperature gradient, was never experimentally investigated. We developed a new sample holder where metamorphism under advective conditions can be observed and measured using time-lapse micro-tomography [1]. Long-term experiments were performed and direct pore-level simulation (DPLS) [2,3] was directly applied on the extracted 3D digital geometry of the snow to calculate the effective transport properties by solving the governing fluid flow equations. The results showed no effect of isothermal advection, compared to rates typical for isothermal metamorphism. Appling a temperature gradient, the results showed increased snow metamorphism compared to rates typical for temperature gradient metamorphism. However, for both cases a change in the isotopic composition in the air as well as in the snow sample could be observed. These measurements could be influential to better understand snow-air exchange processes relevant for atmospheric chemistry and isotopic composition. REFERENCES[1] Ebner P. P., Grimm S., Schneebeli M., and Steinfeld A.: An instrumented sample holder for time-lapse micro-tomography measurements of snow under advective airflow. Geoscientific Instrumentation, Methods and Data Systems 4(2014), 353-373. [2] Zermatten E., Haussener S., Schneebeli M., and Steinfeld A.: Tomography-based determination of permeability and Dupuit-Forchheimer coefficient of characteristic snow samples. Journal of Glaciology 57(2011), 811-816. [3] Zermatten E., Schneebeli M., Arakawa H., and Steinfeld A.: Tomography-based determination of porosity, specific area and permeability of snow and comparison with measurements. Cold Regions Science and Technology 97 (2014), 33-40. Fig. 1: 3-D surface rendering of a refrozen wet snow sample with fluid flow streamline.

  1. Monitoring the geothermal fluid using time lapse electrical resistivity tomography: The Pisciarelli fumarolic field test site (Campi Flegrei, South Italy)

    Science.gov (United States)

    Fedele, Alessandro; Giulia Di Giuseppe, Maria; Troiano, Antonio; Somma, Reanto; Caputo, Teresa; Patella, Domenico; Troise, Claudia; De Natale, Giuseppe

    2015-04-01

    Pisciarelli area is a fumarolic field subject to very short time morphological changes. A number of critical problems affect this area, i.e. increase of temperature of the fumaroles above the average background temperature, local seismicity and occurrence of fumaroles mixed with jets of boiling water. The presence of a very shallow aquifer seem to have the control on the behavior and composition of the fumaroles. This fumarolic field is still largely unknown regarding geophysical surveys mainly because of its limited space, surrounded on the eastern side by intense urbanization inside the large Agnano crater (Troiano et al. 2014). Currently is mainly affected by geochemical, thermal and seismic monitoring which may not fully explain the behaviour of fluids surface. Many monitoring or time lapse (TL) applications are discussed in literature (e.g., White, 1994; Daily et al., 1995; Barker and Moore, 1998; Ramirez and Daily, 2001; Carter, 2002; Slater et al., 2002; Singha and Gorelick, 2005; Cassiani et al., 2006; Swarzenski et al., 2006; de Franco et al., 2009). However all these experiments are devoted to the use of the ERT for tracer tests or in contaminant hydrology and are characterized by a short monitoring period due to the complexity and problems of long-time instrument maintenance. We propose and present a first approach of a geophysical monitoring by time lapse electrical resistivity in a fumarolic field. The profiles were acquired in January 2013, in January, March, May, July, September and November 2014 respectively. They cross the Pisciarelli area following approximately the NS direction and were characterized by a 2.5 m electrode spacing and maximum penetration depth of about 20 m. and will supply fundamental evidences on the possible seasonal resistivity fluctuations or if the resistivity changes are indicative of an increase in volcanic gases present in the hydrothermal system.

  2. Water partitioning and storage via preferential pathways on the hillslope scale observed using time-lapse ERT

    Science.gov (United States)

    Kotikian, M.; Parsekian, A.; Paige, G. B.; Carey, A. M.

    2016-12-01

    Water in the west is primarily sourced from snowmelt in the mountainous alpine zone providing freshwater for rivers and recharge for groundwater aquifers. Subsurface water flow often moves through the soil and fractured rock although its storage, residence time, and partitioning have not been well documented at the hillslope scale. In this study we investigate water partitioning and preferential flow pathways using geophysical methods to complete the water balance. We hypothesize that preferential flow paths will indicate where water is partitioning into groundwater stores and will differ based on the vegetation cover and soil depth. We use daily time-lapse electric resistivity tomography (TL-ERT) to estimate moisture content on seasonal and annual time-scales. Water content is assumed to be the only variable to change over the duration of the measurement after temperature corrections. The ERT measurement is combined with other geophysical measurements including seismic refraction tomography for locating the weathering front, time-lapse borehole nuclear magnetic resonance (NMR) to directly measure changes in water content over the season, and 3D ERT as a control for out-of-plane effects of the 2D TL-ERT measurement. The results show that during snowmelt, the wetting front is heterogeneous and moves down at a rate up to 25 mm/day within the top 5m. A preferential flow path is observed to be moving water to at least 5m depth in one area. This preferential flow anomaly only occurred during snowmelt and was not observed during rainfall-driven infiltration. Heterogeneities in vegetation cover and soil depth result in different water flow behaviors. These results indicate that water storage increases during the snowmelt season and partitioning pathways differ seasonally and with precipitation type.

  3. Osteoclast Fusion: Time-Lapse Reveals Involvement of CD47 and Syncytin-1 at Different Stages of Nuclearity.

    Science.gov (United States)

    Møller, Anaïs Marie Julie; Delaissé, Jean-Marie; Søe, Kent

    2017-06-01

    Investigations addressing the molecular keys of osteoclast fusion are primarily based on end-point analyses. No matter if investigations are performed in vivo or in vitro the impact of a given factor is predominantly analyzed by counting the number of multi-nucleated cells, the number of nuclei per multinucleated cell or TRAcP activity. But end-point analyses do not show how the fusion came about. This would not be a problem if fusion of osteoclasts was a random process and occurred by the same molecular mechanism from beginning to end. However, we and others have in the recent period published data suggesting that fusion partners may specifically select each other and that heterogeneity between the partners seems to play a role. Therefore, we set out to directly test the hypothesis that fusion factors have a heterogenic involvement at different stages of nuclearity. Therefore, we have analyzed individual fusion events using time-lapse and antagonists of CD47 and syncytin-1. All time-lapse recordings have been studied by two independent observers. A total of 1808 fusion events were analyzed. The present study shows that CD47 and syncytin-1 have different roles in osteoclast fusion depending on the nuclearity of fusion partners. While CD47 promotes cell fusions involving mono-nucleated pre-osteoclasts, syncytin-1 promotes fusion of two multi-nucleated osteoclasts, but also reduces the number of fusions between mono-nucleated pre-osteoclasts. Furthermore, CD47 seems to mediate fusion mostly through broad contact surfaces between the partners' cell membrane while syncytin-1 mediate fusion through phagocytic-cup like structure. J. Cell. Physiol. 232: 1396-1403, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. Analysis of Snow Line and Albedo Conditions By Means of Time-Lapse Photography on Tapado Glacier, Chile

    Science.gov (United States)

    Vivero, S.; MacDonell, S.; McPhee, J. P.

    2014-12-01

    In the semiarid Coquimbo Region of Chile, high-altitude glaciers and seasonal snow are important sources of freshwater for irrigated agriculture and urban consumption. Due to the aridity of the environment, losses due to sublimation are large which means that accurate melt modelling is essential in order to reliably estimate streamflow. Since 2008, the CEAZA glaciology group has been studying the energy and mass balance of the largest glacier in the catchment, the Tapado Glacier using field and remote sensing measurements, and numerical modelling. The Tapado glacier system (30°08' S, 69°55' W) is a complex assemblage of uncovered and debris-covered ice located at the head of the Elqui basin between 4500 and 5536 m a.s.l. Energy balance modelling studies at the site have been limited in scope due to the development of ice pinnacles or penitentes on snow and ice surfaces. These features complicate energy distribution across the surface, due to modifications of parameters such as albedo. In this paper, we use time-lapse photography and automatic weather station (AWS) measurements to investigate how the development of penitentes impacts the spatial and temporal variability of albedo across the glacier surface and whether terrestrial photography is appropriate for use at such locations. Oblique photographs obtained from a high vantage point were georeferenced using a high resolution digital elevation model available for the entire glacier and its environs. By comparing the photographic data with point albedo measurements made at an AWS, distributed albedo maps were produced. Preliminary results suggest that distributed albedo values may be underestimated by the formation and development of penitentes during the ablation season. Moreover, it was observed that the evolution of the snow line during summer was not only topographically controlled but also modified by occasional convective snowfalls. Time-lapse photography provided to be a cost-effective tool for monitoring

  5. Assessing Uncertainty and Repeatability in Time-Lapse VSP Monitoring of CO2 Injection in a Brine Aquifer, Frio Formation, Texas (A Case Study)

    Energy Technology Data Exchange (ETDEWEB)

    Nazari, Siamak [Univ. of California, Berkeley, CA (United States). Dept. of Civil and Environmental Engineering; Daley, Thomas M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division

    2013-02-07

    This study was done to assess the repeatability and uncertainty of time-lapse VSP response to CO2 injection in the Frio formation near Houston Texas. A work flow was built to assess the effect of time-lapse injected CO2 into two Frio brine reservoir intervals, the ‘C’ sand (Frio1) and the ‘Blue sand’ (Frio2). The time-lapse seismic amplitude variations with sensor depth for both reservoirs Frio1 and Frio2 were computed by subtracting the seismic response of the base survey from each of the two monitor seismic surveys. Source site 1 has been considered as one of the best sites for evaluating the time-lapse response after injection. For site 1, the computed timelapse NRMS levels after processing had been compared to the estimated time-lapse NRMS level before processing for different control reflectors, and for brine aquifers Frio1, and Frio2 to quantify detectability of amplitude difference. As the main interest is to analyze the time-lapse amplitude variations, different scenarios have been considered. Three different survey scenarios were considered: the base survey which was performed before injection, monitor1 performed after the first injection operation, and monitor2 which was after the second injection. The first scenario was base-monitor1, the second was basemonitor2, and the third was monitor1-monitor2. We considered three ‘control’ reflections above the Frio to assist removal of overburden changes, and concluded that third control reflector (CR3) is the most favorable for the first scenario in terms of NRMS response, and first control reflector (CR1) is the most favorable for the second and third scenarios in terms of NRMS response. The NRMS parameter is shown to be a useful measure to assess the effect of processing on time-lapse data. The overall NRMS for the Frio VSP data set was found to be in the range of 30% to 80% following basic processing. This could be considered as an estimated baseline in assessing the utility

  6. TIME-LAPSE MICROSCOPY ROLE IN IMPROVING THE OUTCOME OF IVF/ICSI CYCLES BY MONITORING AND SELECTION OF EARLY EMBRYO

    Directory of Open Access Journals (Sweden)

    Gabriela SIMIONESCU

    2016-12-01

    Full Text Available In vitro fertilization (IVF and intracytoplasmatic sperm injection (ICSI are well-established assisted reproductive biotechnologies used to overcome infertility in couples. Time-lapse monitoring is an imagistic technology which was elaborated to fulfill the need for observing the dynamics of the mammalian embryonic development in a continuous, non-invasive manner, without removing the embryos from the optimal culturing conditions. This technology offers unique information regarding the cleavage process, as well as morphological and structural modifications thus enabling the embryologists to select the embryos with elevated implantation potential. Aim of the study: to identify, evaluate and summarize the available data regarding the role of time-lapse microscopy in improving the outcome of IVF and ICSI by monitoring and selection of early embryos Material and methods: we systematically reviewed the available evidence regarding the assessment of embryo quality through both conventional monitoring and time-lapse microscopy for couples undergoing in vitro fertilization (IVF or intracytoplasmic sperm injection (ICSI. The meta analysis included randomized trials and published data encountered on ISI Web of Knowledge Science, MedLine and Pubmed using the following keywords: time-lapse microscopy, IVF, ICSI, embryo, outcome, pregnancy. As criteria of differentiation, only studies that reported information regarding the implantation rate, aspects regarding clinical pregnancy or live birth were considered for analysis. Results: the info from the studies was extracted and included in the meta-analysis. A part of the retrospective studies conducted after 2010 have highlighted a correlation between time-lapse parameters and embryo viability as defined by the developmental competence and subsequently by the confirmation of clinical pregnancy. Other authors undertook a critical appraisal on potential benefit time-lapse monitoring may bring to ART. Conclusion

  7. Visual attention: a rhythmic process?

    Science.gov (United States)

    VanRullen, Rufin

    2013-12-16

    Vision involves constant exploration of the environment by eye movements. Recent evidence suggests that a rhythmic form of exploration also occurs under covert attention, in the absence of eye movements. Sustained attention naturally fluctuates, with a periodicity in the theta (4-8 Hz) frequency range. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Concrete Operations and Attentional Capacity.

    Science.gov (United States)

    Chapman, Michael; Lindenberger, Ulman

    1989-01-01

    To test predictions regarding the attentional capacity requirements of Piaget's stage of concrete operations, a battery of concrete operational tasks and two measures of attentional capacity were administered to 120 first-, second-, and third-graders. Findings concern class inclusion, transitivity of length and weight, and multiplication of…

  9. Caffeine Modulates Attention Network Function

    Science.gov (United States)

    Brunye, Tad T.; Mahoney, Caroline R.; Lieberman, Harris R.; Taylor, Holly A.

    2010-01-01

    The present work investigated the effects of caffeine (0 mg, 100 mg, 200 mg, 400 mg) on a flanker task designed to test Posner's three visual attention network functions: alerting, orienting, and executive control [Posner, M. I. (2004). "Cognitive neuroscience of attention". New York, NY: Guilford Press]. In a placebo-controlled, double-blind…

  10. Social reward shapes attentional biases.

    Science.gov (United States)

    Anderson, Brian A

    2016-01-01

    Paying attention to stimuli that predict a reward outcome is important for an organism to survive and thrive. When visual stimuli are associated with tangible, extrinsic rewards such as money or food, these stimuli acquire high attentional priority and come to automatically capture attention. In humans and other primates, however, many behaviors are not motivated directly by such extrinsic rewards, but rather by the social feedback that results from performing those behaviors. In the present study, I examine whether positive social feedback can similarly influence attentional bias. The results show that stimuli previously associated with a high probability of positive social feedback elicit value-driven attentional capture, much like stimuli associated with extrinsic rewards. Unlike with extrinsic rewards, however, such stimuli also influence task-specific motivation. My findings offer a potential mechanism by which social reward shapes the information that we prioritize when perceiving the world around us.

  11. Attention enhances apparent perceptual organization.

    Science.gov (United States)

    Barbot, Antoine; Liu, Sirui; Kimchi, Ruth; Carrasco, Marisa

    2017-08-28

    Perceptual organization and selective attention are two crucial processes that influence how we perceive visual information. The former structures complex visual inputs into coherent units, whereas the later selects relevant information. Attention and perceptual organization can modulate each other, affecting visual processing and performance in various tasks and conditions. Here, we tested whether attention can alter the way multiple elements appear to be perceptually organized. We manipulated covert spatial attention using a rapid serial visual presentation task, and measured perceptual organization of two multielements arrays organized by luminance similarity as rows or columns, at both the attended and unattended locations. We found that the apparent perceptual organization of the multielement arrays is intensified when attended and attenuated when unattended. We ruled out response bias as an alternative explanation. These findings reveal that attention enhances the appearance of perceptual organization, a midlevel vision process, altering the way we perceive our visual environment.

  12. What Attracts Decision Makers' Attention?

    DEFF Research Database (Denmark)

    Bentzen, Eric; Christiansen, John K.; Varnes, Claus J.

    2011-01-01

    portfolio meetings. The study seeks to investigate how managers allocate their attention and the role of different factors for their attention. Observations also make it possible to compare prior research and expectations with the actual observed behavior of decision makers. Design....../methodology/approach – The present analysis draws on insights from previous research into decision making in product and portfolio management and studies on organizational decision making. The authors frame why the attention of decision makers is so critical in complex situations. Data for this study were collected through direct......Purpose – Managers' attention is a scarce resource in complex innovation settings. Prior research on the factors to which managers pay attention is mostly based on surveys. The present study aims to address the need for knowledge about the behavior of decision makers based on observations from...

  13. Combining segmentation and attention: a new foveal attention model

    Directory of Open Access Journals (Sweden)

    Rebeca eMarfil

    2014-08-01

    Full Text Available Artificial vision systems cannot process all the information that they receive from the world in real time because it is highly expensive and inefficient in terms of computational cost. Inspired by biological perception systems, articial attention models pursuit to select only the relevant part of the scene. Besides, it is well established that the units of attention on human vision are not merely spatial but closely related to perceptual objects (proto-objects. This implies a strong bidirectional relationship between segmentation and attention processes. Therefore, while the segmentation process is the responsible to extract the proto-objects from the scene, attention can guide segmentation, arising the concept of foveal attention. When the focus of attention is deployed from one visual unit to another, the rest of the scene is perceived but at a lower resolution that the focused object. The result is a multi-resolution visual perception in which the fovea, a dimple on the central retina, provides the highest resolution vision. In this paper, a bottom-up foveal attention model is presented. In this model the input image is a foveal image represented using a Cartesian Foveal Geometry (CFG, which encodes the field of view of the sensor as a fovea (placed in the focus of attention surrounded by a set of concentric rings with decreasing resolution. Then multirresolution perceptual segmentation is performed by building a foveal polygon using the Bounded Irregular Pyramid (BIP. Bottom-up attention is enclosed in the same structure, allowing to set the fovea over the most salient image proto-object. Saliency is computed as a linear combination of multiple low level features such us colour and intensity contrast, symmetry, orientation and roundness. Obtained results from natural images show that the performance of the combination of hierarchical foveal segmentation and saliency estimation is good in terms of accuracy and speed.

  14. Brain activity associated with selective attention, divided attention and distraction.

    Science.gov (United States)

    Salo, Emma; Salmela, Viljami; Salmi, Juha; Numminen, Jussi; Alho, Kimmo

    2017-06-01

    Top-down controlled selective or divided attention to sounds and visual objects, as well as bottom-up triggered attention to auditory and visual distractors, has been widely investigated. However, no study has systematically compared brain activations related to all these types of attention. To this end, we used functional magnetic resonance imaging (fMRI) to measure brain activity in participants performing a tone pitch or a foveal grating orientation discrimination task, or both, distracted by novel sounds not sharing frequencies with the tones or by extrafoveal visual textures. To force focusing of attention to tones or gratings, or both, task difficulty was kept constantly high with an adaptive staircase method. A whole brain analysis of variance (ANOVA) revealed fronto-parietal attention networks for both selective auditory and visual attention. A subsequent conjunction analysis indicated partial overlaps of these networks. However, like some previous studies, the present results also suggest segregation of prefrontal areas involved in the control of auditory and visual attention. The ANOVA also suggested, and another conjunction analysis confirmed, an additional activity enhancement in the left middle frontal gyrus related to divided attention supporting the role of this area in top-down integration of dual task performance. Distractors expectedly disrupted task performance. However, contrary to our expectations, activations specifically related to the distractors were found only in the auditory and visual cortices. This suggests gating of the distractors from further processing perhaps due to strictly focused attention in the current demanding discrimination tasks. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Application of time-lapse seismic shear wave inversion to characterize the stimulated rock volume in the Niobrara and Codell Reservoirs, Wattenberg Field, CO

    Science.gov (United States)

    Mueller, Staci K.

    Advances in horizontal drilling and completions in shale reservoirs have allowed operators to extract hydrocarbons within low permeability reservoirs that were once impossible to access. The integration of time-lapse multicomponent seismic data with engineering technology aids in the characterization of these reservoirs through monitoring. This thesis investigates the fast and slow shear wave components of a time-lapse, nine-component seismic survey to determine the stimulated volume in the Niobrara and Codell reservoir intervals. The time-lapse post-stack inversions of the shear wave datasets provide insight into how the shear impedance is affected by hydraulic fracturing through the work of cross-equalized seismic shear impedances and shear wave splitting. The study area is the Wishbone Section within Wattenberg Field, CO, which is owned and operated by Anadarko Petroleum Corporation and contains eleven horizontal wells that vary in spacing and completion methods. Shear seismic data sets were acquired over this section before and after hydraulic stimulation. The time-lapse shear seismic inversions show an increase in fast shear wave velocity and a decrease in slow shear velocity after stimulation. The sensitivity of both the fast and slow shear seismic to stimulation correlates with the net pressure trends at each stage. Borehole image log interpretations are compared to the inversions to analyze the affect that a complex fracture network has on induced anisotropy. The stimulated volume for the Niobrara and Codell reservoir intervals are now more accurately defined. Time-lapse shear seismic is the only technology that is able to define the stimulated rock volume and reveal areas that are not being accessed by the wells currently drilled. These areas are now detected within the Wishbone section, and may be candidates for future re-completion.

  16. How Do Medical Schools Identify and Remediate Professionalism Lapses in Medical Students? A Study of U.S. and Canadian Medical Schools.

    Science.gov (United States)

    Ziring, Deborah; Danoff, Deborah; Grosseman, Suely; Langer, Debra; Esposito, Amanda; Jan, Mian Kouresch; Rosenzweig, Steven; Novack, Dennis

    2015-07-01

    Teaching and assessing professionalism is an essential element of medical education, mandated by accrediting bodies. Responding to a call for comprehensive research on remediation of student professionalism lapses, the authors explored current medical school policies and practices. In 2012-2013, key administrators at U.S. and Canadian medical schools accredited by the Liaison Committee on Medical Education were interviewed via telephone or e-mail. The structured interview questionnaire contained open-ended and closed questions about practices for monitoring student professionalism, strategies for remediating lapses, and strengths and limitations of current systems. The authors employed a mixed-methods approach, using descriptive statistics and qualitative analysis based on grounded theory. Ninety-three (60.8%) of 153 eligible schools participated. Most (74/93; 79.6%) had specific policies and processes regarding professionalism lapses. Student affairs deans and course/clerkship directors were typically responsible for remediation oversight. Approaches for identifying lapses included incident-based reporting and routine student evaluations. The most common remediation strategies reported by schools that had remediated lapses were mandated mental health evaluation (74/90; 82.2%), remediation assignments (66/90; 73.3%), and professionalism mentoring (66/90; 73.3%). System strengths included catching minor offenses early, emphasizing professionalism schoolwide, focusing on helping rather than punishing students, and assuring transparency and good communication. System weaknesses included reluctance to report (by students and faculty), lack of faculty training, unclear policies, and ineffective remediation. In addition, considerable variability in feedforward processes existed between schools. The identified strengths can be used in developing best practices until studies of the strategies' effectiveness are conducted.

  17. Cognitive control and attentional functions.

    Science.gov (United States)

    Mackie, Melissa-Ann; Van Dam, Nicholas T; Fan, Jin

    2013-08-01

    Cognitive control is essential to flexible, goal-directed behavior under uncertainty, yet its underlying mechanisms are not clearly understood. Because attentional functions are known to allocate mental resources and prioritize the information to be processed, we propose that the attentional functions of alerting, orienting, and executive control and the interactions among them contribute to cognitive control in the service of uncertainty reduction. To test this hypothesis, we examined the relationship between cognitive control and attentional functions. We used the Majority Function Task (MFT) to manipulate uncertainty in order to evoke cognitive control along with the Revised Attention Network Test (ANT-R) to measure the efficiency and the interactions of attentional functions. A backwards, stepwise regression model revealed that performance on the MFT could be significantly predicted by attentional functions and their interactions as measured by the ANT-R. These results provide preliminary support for our theory that the attentional functions are involved in the implementation of cognitive control as required to reduce uncertainty, though further investigation is needed. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Extended attention span training system

    Science.gov (United States)

    Pope, Alan T.; Bogart, Edward H.

    1991-01-01

    Attention Deficit Disorder (ADD) is a behavioral disorder characterized by the inability to sustain attention long enough to perform activities such as schoolwork or organized play. Treatments for this disorder include medication and brainwave biofeedback training. Brainwave biofeedback training systems feed back information to the trainee showing him how well he is producing the brainwave pattern that indicates attention. The Extended Attention Span Training (EAST) system takes the concept a step further by making a video game more difficult as the player's brainwaves indicate that attention is waning. The trainee can succeed at the game only by maintaining an adequate level of attention. The EAST system is a modification of a biocybernetic system that is currently being used to assess the extent to which automated flight management systems maintain pilot engagement. This biocybernetic system is a product of a program aimed at developing methods to evaluate automated flight deck designs for compatibility with human capabilities. The EAST technology can make a contribution in the fields of medical neuropsychology and neurology, where the emphasis is on cautious, conservative treatment of youngsters with attention disorders.

  19. Rewards teach visual selective attention.

    Science.gov (United States)

    Chelazzi, Leonardo; Perlato, Andrea; Santandrea, Elisa; Della Libera, Chiara

    2013-06-07

    Visual selective attention is the brain function that modulates ongoing processing of retinal input in order for selected representations to gain privileged access to perceptual awareness and guide behavior. Enhanced analysis of currently relevant or otherwise salient information is often accompanied by suppressed processing of the less relevant or salient input. Recent findings indicate that rewards exert a powerful influence on the deployment of visual selective attention. Such influence takes different forms depending on the specific protocol adopted in the given study. In some cases, the prospect of earning a larger reward in relation to a specific stimulus or location biases attention accordingly in order to maximize overall gain. This is mediated by an effect of reward acting as a type of incentive motivation for the strategic control of attention. In contrast, reward delivery can directly alter the processing of specific stimuli by increasing their attentional priority, and this can be measured even when rewards are no longer involved, reflecting a form of reward-mediated attentional learning. As a further development, recent work demonstrates that rewards can affect attentional learning in dissociable ways depending on whether rewards are perceived as feedback on performance or instead are registered as random-like events occurring during task performance. Specifically, it appears that visual selective attention is shaped by two distinct reward-related learning mechanisms: one requiring active monitoring of performance and outcome, and a second one detecting the sheer association between objects in the environment (whether attended or ignored) and the more-or-less rewarding events that accompany them. Overall this emerging literature demonstrates unequivocally that rewards "teach" visual selective attention so that processing resources will be allocated to objects, features and locations which are likely to optimize the organism's interaction with the

  20. External noise distinguishes attention mechanisms.

    Science.gov (United States)

    Lu, Z L; Dosher, B A

    1998-05-01

    We developed and tested a powerful method for identifying and characterizing the effect of attention on performance in visual tasks as due to signal enhancement, distractor exclusion, or internal noise suppression. Based on a noisy Perceptual Template Model (PTM) of a human observer, the method adds increasing amounts of external noise (white gaussian random noise) to the visual stimulus and observes the effect on performance of a perceptual task for attended and unattended stimuli. The three mechanisms of attention yield three "signature" patterns of performance. The general framework for characterizing the mechanisms of attention is used here to investigate the attentional mechanisms in a concurrent location-cued orientation discrimination task. Test stimuli--Gabor patches tilted slightly to the right or left--always appeared on both the left and the right of fixation, and varied independently. Observers were cued on each trial to attend to the left, the right, or evenly to both stimuli, and decide the direction of tilt of both test stimuli. For eight levels of added external noise and three attention conditions (attended, unattended, and equal), subjects' contrast threshold levels were determined. At low levels of external noise, attention affected threshold contrast: threshold contrasts for non-attended stimuli were systematically higher than for equal attention stimuli, which were, in turn, higher than for attended stimuli. Specifically, when the rms contrast of the external noise is below 10%, there is a consistent 17% elevation of contrast threshold from attended to unattended condition across all three subjects. For higher levels of external noise, attention conditions did not affect threshold contrast values at all. These strong results are characteristic of a signal enhancement, or equivalently, an internal additive noise reduction mechanism of attention.

  1. [Neuropsychological approach to visual attention].

    Science.gov (United States)

    Suzuki, Kyoko

    2007-01-01

    Visual experience depends critically on visual attention, which selects a particular aspect of a visual display. Recent clinical, neuroimaging, and animal studies revealed that visual attention was divided into active and passive or top-down and bottom-up attention. Although these dichotomies are clear-cut in definition, visual attention could be modulated by many factors. Detailed observation of brain-injured patients provides with evidence for dynamic and fine control of visual attention. We observed patients with dorsal simultanagnosia and that with callosal disconnection syndrome. Patients with dorsal simultanagnosia demonstrated that extent of visual attention was dynamically changed depending on the level of visual processing. Despite the ability to read a kanji character and to describe its components correctly, a patient could not notice a component that he had just written and could not assemble individual components to make up a correct kanji character. He could point to an overlapping area of two figures. But once he started to color the overlapping area, he missed the margin of the area and colored much larger area. Another patient with dorsal simultanagnosia missed borderlines between columns of a newspaper and read letters continuously across columns. In contrast, he could point to lines between figures or meaningless patterns easily. These findings indicated that visual attention was directed automatically to meaningful characters. A patients with callosal disconnection syndrome demonstrated left unilateral spatial neglect only when he used his right hand to draw figures. Right hand movement, controlled by the left hemisphere, elicited visual attention to the right hemispace, resulting in the left unilateral spatial neglect. Thus visual attention is not simply top-down or bottom up, but is implicitly affected by the visual recognition as well as motor component of the task.

  2. Cold-Blooded Attention: Finger Temperature Predicts Attentional Performance

    Directory of Open Access Journals (Sweden)

    Rodrigo C. Vergara

    2017-09-01

    Full Text Available Thermal stress has been shown to increase the chances of unsafe behavior during industrial and driving performances due to reductions in mental and attentional resources. Nonetheless, establishing appropriate safety standards regarding environmental temperature has been a major problem, as modulations are also be affected by the task type, complexity, workload, duration, and previous experience with the task. To bypass this attentional and thermoregulatory problem, we focused on the body rather than environmental temperature. Specifically, we measured tympanic, forehead, finger and environmental temperatures accompanied by a battery of attentional tasks. We considered a 10 min baseline period wherein subjects were instructed to sit and relax, followed by three attentional tasks: a continuous performance task (CPT, a flanker task (FT and a counting task (CT. Using multiple linear regression models, we evaluated which variable(s were the best predictors of performance. The results showed a decrement in finger temperature due to instruction and task engagement that was absent when the subject was instructed to relax. No changes were observed in tympanic or forehead temperatures, while the environmental temperature remained almost constant for each subject. Specifically, the magnitude of the change in finger temperature was the best predictor of performance in all three attentional tasks. The results presented here suggest that finger temperature can be used as a predictor of alertness, as it predicted performance in attentional tasks better than environmental temperature. These findings strongly support that peripheral temperature can be used as a tool to prevent unsafe behaviors and accidents.

  3. Early vision and visual attention

    Directory of Open Access Journals (Sweden)

    Gvozdenović Vasilije P.

    2003-01-01

    Full Text Available The question whether visual perception is spontaneous, sudden or is running through several phases, mediated by higher cognitive processes, was raised ever since the early work of Gestalt psychologists. In the early 1980s, Treisman proposed the feature integration theory of attention (FIT, based on the findings of neuroscience. Soon after publishing her theory a new scientific approach appeared investigating several visual perception phenomena. The most widely researched were the key constructs of FIT, like types of visual search and the role of the attention. The following review describes the main studies of early vision and visual attention.

  4. Tips for Beginners: Attention Getters.

    Science.gov (United States)

    Moldavan, Carla

    1993-01-01

    Proposes the use of humor and the personalization of word problems by inserting students' names in the problem statement as methods of gaining students' attention. Illustrates their use in a mixture problem and the Tower of Hanoi problem. (MDH)

  5. Visual attention in posterior stroke

    DEFF Research Database (Denmark)

    Fabricius, Charlotte; Petersen, Anders; Iversen, Helle K

    Objective: Impaired visual attention is common following strokes in the territory of the middle cerebral artery, particularly in the right hemisphere. However, attentional effects of more posterior lesions are less clear. The aim of this study was to characterize visual processing speed...... and apprehension span following posterior cerebral artery (PCA) stroke. We also relate these attentional parameters to visual word recognition, as previous studies have suggested that reduced visual speed and span may explain pure alexia. Methods: Nine patients with MR-verified focal lesions in the PCA......-territory (four left PCA; four right PCA; one bilateral, all >1 year post stroke) were compared to 25 controls using single case statistics. Visual attention was characterized by a whole report paradigm allowing for hemifield-specific speed and span measurements. We also characterized visual field defects...

  6. Attention Deficit Hyperactivity Disorder (ADHD)

    Science.gov (United States)

    ... NIH About Mission The NIH Director Organization Budget History NIH Almanac Public Involvement Outreach & Education Visitor Information RePORT NIH Fact Sheets Home > Attention Deficit Hyperactivity Disorder (ADHD) Small Text Medium Text Large Text ...

  7. Mindfulness training affects attention--or is it attentional effort?

    Science.gov (United States)

    Jensen, Christian Gaden; Vangkilde, Signe; Frokjaer, Vibe; Hasselbalch, Steen G

    2012-02-01

    Improvements in attentional performance are at the core of proposed mechanisms for stress reduction in mindfulness meditation practices. However, this claim can be questioned because no previous studies have actively manipulated test effort in control groups and controlled for effects of stress reduction per se. In a blinded design, 48 young, healthy meditation novices were randomly assigned to a mindfulness-based stress reduction (MBSR), nonmindfulness stress reduction (NMSR), or inactive control group. At posttest, inactive controls were randomly split into nonincentive and incentive controls, the latter receiving a financial reward to improve attentional performance. Pre- and postintervention, 5 validated attention paradigms were employed along with self-report scales on mindfulness and perceived stress and saliva cortisol samples to measure physiological stress. Attentional effects of MBSR, NMSR, and the financial incentive were comparable or significantly larger in the incentive group on all reaction-time-based measures. However, selective attention in the MBSR group improved significantly more than in any other group. Similarly, only the MBSR intervention improved the threshold for conscious perception and visual working memory capacity. Furthermore, stress-reducing effects of MBSR were supported because those in the MBSR group showed significantly less perceived and physiological stress while increasing their mindfulness levels significantly. We argue that MBSR may contribute uniquely to attentional improvements but that further research focusing on non-reaction-time-based measures and outcomes less confounded by test effort is needed. Critically, our data demonstrate that previously observed improvements of attention after MBSR may be seriously confounded by test effort and nonmindfulness stress reduction.

  8. Visual Selective Attention in Mice.

    Science.gov (United States)

    Wang, Lupeng; Krauzlis, Richard J

    2018-02-08

    Visual selective attention is a fundamental cognitive ability that allows us to process relevant visual stimuli while ignoring irrelevant distracters and has been extensively studied in human and non-human primate subjects. Mice have emerged as a powerful animal model for studying aspects of the visual system but have not yet been shown to exhibit visual selective attention. Differences in the organization of the visual systems of primates and mice raise the possibility that selective visual attention might not be present in mice, at least not in the forms that are well established in primates. Here, we tested for selective visual attention in mice by using three behavioral paradigms adapted from classic studies of attention. In a Posner-style cueing task, a spatial cue indicated the probable location of the relevant visual event, and we found that accuracy was higher and reaction times were shorter on validly cued trials. In a cue versus no-cue task, an informative spatial cue was provided on half the trials, and mice had higher accuracy and shorter reaction times with spatial cues and also lower detection thresholds measured from psychometric curves. In a filter task, the spatial cue indicated the location of the relevant visual event, and we found that mice could be trained to ignore irrelevant but otherwise identical visual events at uncued locations. Together, these results demonstrate that mice exhibit visual selective attention, paving the way to use classic attention paradigms in mice to study the genetic and neuronal circuit mechanisms of selective attention. Published by Elsevier Ltd.

  9. Dividing Attention Increases Operational Momentum

    Directory of Open Access Journals (Sweden)

    Koleen McCrink

    2017-12-01

    Full Text Available When adding or subtracting two quantities, adults often compute an estimated outcome that is larger or smaller, respectively, than the actual outcome, a bias referred to as “operational momentum”. The effects of attention on operational momentum were investigated. Participants viewed a display in which two arrays of objects were added, or one array was subtracted from another array, and judged whether a subsequent outcome (probe array contained the correct or incorrect number of objects. In a baseline condition, only the arrays to be added or subtracted were viewed. In divided attention conditions, participants simultaneously viewed a sequence of colors or shapes, and judged which color (a non-spatial judgment or shape (a spatial judgment was repeated. Operational momentum occurred in all conditions, but was higher in divided attention conditions than in the baseline condition, primarily for addition problems. This pattern suggests that dividing attention, rather than decreasing operational momentum by decreasing attentional shifts, actually increased operational momentum. These results are consistent with a heightened use of arithmetic heuristics under conditions of divided attention.

  10. Time-lapse gravity and levelling in the sinkhole-endangered urban area of Bad Frankenhausen, Germany

    Science.gov (United States)

    Kobe, Martin; Gabriel, Gerald; Weise, Adelheid; Krawczyk, Charlotte; Vogel, Detlef

    2017-04-01

    Sinkholes, resulting from subrosion in the subsurface, can reach diameters of several hundred meters and thus pose a severe hazard for infrastructure and inhabitants in urban areas. Subrosion is the leaching of readily-soluble rocks, such as rock salt, gypsum, anhydrite and limestone by ground or meteoric water and leads to mass transport and relocation. Two scenarios of sinkhole evolution are conceivable: First, the surface subsides continuously in order to compensate for the mass loss. Second, the mass relocation leads to development of subsurface cavities. If they reach a critical size and the cover layers are not supported anymore, the surface collapses abruptly. To improve the understanding of subrosion processes and the related surface deformation a case study is conducted in Bad Frankenhausen, Germany, where subrosion leaches the Zechstein evaporates of the Permian. One part of the study is to analyse the spatiotemporal development of sinkholes by applying time-lapse observations. Therefore, we established a monitoring network consisting of 15 gravity and additional levelling points covering the main sinkhole areas in the city centre. In March 2014, the baseline survey was carried out. Since then, quarterly measurement campaigns are performed. In each campaign four different gravity meters are used to collect a statistical significant amount of data and to control the plausibility of our data. The gravity measurements are complemented by levelling surveys. The rectification of the time-lapse gravity data comprises the correction for jumps and systematic errors, as well as for well calculable influences, such as earth tides and air pressure changes. Furthermore, special interest was applied to seasonal changes of hydrological parameters such as soil moisture or groundwater level. We found the hydrological influence to be in the single digit up to the lower two-digit µGal range, depending on the season and the station. The standard deviations of the adjusted

  11. Effect of attention control on sustained attention during induced anxiety.

    Science.gov (United States)

    Grillon, Christian; Robinson, Oliver J; Mathur, Ambika; Ernst, Monique

    2016-01-01

    Anxiety has wide-reaching and complex effects on cognitive performance. Although it can intrude on cognition and interfere with performance, it can also facilitate information processing and behavioural responses. In a previous study, we showed that anxiety induced by threat of shock facilitates performance on the Sustained Attention to Response Task, a vigilance test, which probes response inhibition to infrequent nogo stimuli. The present study sought to identify factors that may have contributed to such improved performance, including on- and off-task thinking (assessed with thought probes) and individual differences in attention control, as measured with the Attention Control Scale. Replicating our prior finding, we showed that shock threat significantly reduced errors of commission on the nogo trials. However, we extended this finding in demonstrating that this effect was driven by subjects with low attention control. We therefore confirm that anxiety increases inhibitory control of prepotent responses--a mechanism which is adaptive under threat--and show that this effect is greater in those who rely more upon such prepotent responding, i.e., those with low attentional control.

  12. Driving behaviour in adults with attention deficit/hyperactivity disorder.

    Science.gov (United States)

    Groom, Madeleine J; van Loon, Editha; Daley, David; Chapman, Peter; Hollis, Chris

    2015-07-28

    Little is known about the impact of cognitive impairments on driving in adults with ADHD. The present study compared the performance of adults with and without ADHD in a driving simulator on two different routes: an urban route which we hypothesised would exacerbate weak impulse control in ADHD and a motorway route, to challenge deficits in sustained attention. Adults with (n = 22, 16 males) and without (n = 21, 18 males) ADHD completed a simulated driving session while eye movement data were recorded simultaneously. Participants also completed the Manchester Driving Behaviour Questionnaire (DBQ) and the Conners Adult ADHD Rating Scale (CAARS). Measures of driving performance included average speed, proportion distance travelled over speed limit (speeding) and lane deviation. These variables and the eye movement measures (spread of fixations, mean fixation duration) were compared between groups and routes. Also, driving behaviours, including responses to programmed events, were categorised and the frequencies within categories were compared between groups. Finally, speech analysis was performed to compare emotional verbal expressions during driving between groups. ADHD participants reported significantly more Violations and Lapses on the DBQ than control participants and significantly more accidents. Average speed and speeding were also higher but did not interact with route type. ADHD participants showed poorer vehicle control, greater levels of frustration with other road users (including greater frequencies of negative comments) and a trend for less safe driving when changing lanes/overtaking on the motorway. These effects were predicted by hyperactive/impulsive CAARS scores. They were also more likely to cause a crash/near miss when an event occurred on the urban route. The results suggest that difficulty regulating and controlling impulsive behavior, reflected in speeding, frustration with other road users, less safety when changing lanes on the

  13. Field measurement of erosion rates: time-lapse monitoring of rapid stone flaking at Howden Minster, UK

    Science.gov (United States)

    Doehne, E.; Pinchin, S.

    2012-04-01

    The use of a solar-powered, field time-lapse camera and environmental monitoring system enabled measurements of the pattern and rate of loss of stone from the surface of Howden Minster, an abandoned monastery in Yorkshire dating to 1380 AD. Acquiring a photograph every 1-3 hours allowed the stone damage to be correlated with local environmental conditions. Image comparison techniques borrowed from observational astronomy, such as blink comparison, were used to determine what elements had changed from image to image. Results indicate that loss is episodic rather than continuous and in several cases is related to specific environmental conditions, such as condensation/dew formation or high winds. Damage was found also to be synchronous, with surface change (flaking, granular disintegration, and loss of flakes) occurring at the same time on different stone blocks. Crystallization pressure from magnesium sulfate phase transitions appear to be the main cause of the loss of stone surfaces. Significant variation in surface loss rates was observed and appears to be related to variations in salt concentration. An examination of stone texture by ESEM/EDS revealed signification variations and suggests that salt concentrations are controlled in part by stone micromorphology. Quantitative data on rates of surface loss are not available from most monuments. Time-lapse methods permit the relatively inexpensive acquisition of this type of data, which is needed to aid conservation decision-making and the evaluation of interventions. Such tools should also prove useful to geomorphologists studying honeycomb weathering, the moving rocks on Death Valley's Racetrack Playa, and other phenomena that are otherwise difficult to study. Context: The rapid deterioration of magnesian limestone structures in the north of England has been a serious problem for more than one hundred years. While air quality in England has improved during this period, the rate of stone loss in these carved stone

  14. Exploring what lies behind public preferences for avoiding health losses caused by lapses in healthcare safety and patient lifestyle choices.

    Science.gov (United States)

    Singh, Jeshika; Longworth, Louise; Baine, Amanda; Lord, Joanne; Orr, Shepley; Buxton, Martin

    2013-07-02

    Although many studies have identified public preferences for prioritising health care interventions based on characteristics of recipient or care, very few of them have examined the reasons for the stated preferences. We conducted an on-line person trade-off (PTO) study (N=1030) to investigate whether the public attach a premium to the avoidance of ill health associated with alternative types of responsibilities: lapses in healthcare safety, those caused by individual action or lifestyle choice; or genetic conditions. We found that the public gave higher priority to prevention of harm in a hospital setting such as preventing hospital associated infections than genetic disorder but drug administration errors were valued similar to genetic disorders. Prevention of staff injuries, lifestyle diseases and sports injuries, were given lower priority. In this paper we aim to understand the reasoning behind the responses by analysing comments provided by respondents to the PTO questions. A majority of the respondents who participated in the survey provided brief comments explaining preferences in free text responses following PTO questions. This qualitative data was transformed into explicit codes conveying similar meanings. An overall coding framework was developed and a reliability test was carried out. Recurrent patterns were identified in each preference group. Comments which challenged the assumptions of hypothetical scenarios were also investigated. NHS causation of illness and a duty of care were the most cited reasons to prioritise lapses in healthcare safety. Personal responsibility dominated responses for lifestyle related contexts, and many respondents mentioned that health loss was the result of the individual's choice to engage in risky behaviour. A small proportion of responses questioned the assumptions underlying the PTO questions. However excluding these from the main analysis did not affect the conclusions. Although some responses indicated

  15. Does mindfulness meditation improve attention in attention deficit hyperactivity disorder?

    Science.gov (United States)

    Modesto-Lowe, Vania; Farahmand, Pantea; Chaplin, Margaret; Sarro, Lauren

    2015-01-01

    Attention deficit hyperactivity disorder (ADHD) manifests by high levels of inattention, impulsiveness and hyperactivity. ADHD starts in childhood and results in impairments that continue into adulthood. While hyperactivity declines over time, inattention and executive function difficulties persist, leading to functional deficits. Adolescents and adults with ADHD have pervasive impairment in interpersonal and family relationships. They may develop addiction, delinquent behavior and comorbid psychiatric disorders. Despite advances in diagnosis and treatment, persistent residual symptoms are common, highlighting the need for novel treatment strategies. Mindfulness training, derived from Eastern meditation practices, may improve self-regulation of attention. It may also be a useful strategy to augment standard ADHD treatments and may be used as a potential tool to reduce impairments in patients with residual symptoms of ADHD. Clinically, this would manifest by an increased ability to suppress task-unrelated thoughts and distractions resulting in improved attention, completion of tasks and potential improvement in occupational and social function. PMID:26740931

  16. Residual Attention Network for Image Classification

    OpenAIRE

    Wang, Fei; Jiang, Mengqing; Qian, Chen; Yang, Shuo; Li, Cheng; Zhang, Honggang; Wang, Xiaogang; Tang, Xiaoou

    2017-01-01

    In this work, we propose "Residual Attention Network", a convolutional neural network using attention mechanism which can incorporate with state-of-art feed forward network architecture in an end-to-end training fashion. Our Residual Attention Network is built by stacking Attention Modules which generate attention-aware features. The attention-aware features from different modules change adaptively as layers going deeper. Inside each Attention Module, bottom-up top-down feedforward structure ...

  17. Influence of attentional load on spatial attention in acquired and developmental disorders of attention.

    Science.gov (United States)

    Bellgrove, Mark A; Eramudugolla, Ranmalee; Newman, Daniel P; Vance, Alasdair; Mattingley, Jason B

    2013-05-01

    Converging evidence suggests that right-hemisphere dominant spatial attention systems can be modulated by non-spatial processes such as attentional capacity. The severity of neglect in right-hemisphere stroke patients for example, is correlated with impairments in non-lateralized attention. Evidence also suggests the coexistence of lateralized inattention and reduced capacity in developmental disorders of attention, such as attention deficit hyperactivity disorder (ADHD), which is marked by cognitive impairments suggestive of right hemisphere dysfunction. These lines of evidence argue against a coincident damage hypothesis and suggest instead a direct modulation of spatial attention by non-spatial processes. Here we sought experimental evidence for this relationship in both acquired and developmental disorders of attention. Six adult stroke patients with focal right brain injury and 19 children with ADHD were studied in comparison to control groups of both healthy older adults and typically developing children. The participants were required to detect transient, unilateral visual targets while simultaneously monitoring a stream of alphanumeric characters at fixation. Load at fixation was manipulated by asking participants either to ignore the central stream and focus on the peripheral detection task (no report condition), or to monitor the central stream for a probe item that was defined by either a unique feature (low load condition) or a conjunction of features (high load condition). As expected, in all participants greater load at fixation slowed responses to peripheral targets. Crucially, in right brain injured patients but not older healthy adults left target detection was slowed significantly more than central and right target detection. A qualitatively similar pattern was seen in children with ADHD, but not in typically developing children. The imposition of load at fixation slowed responses to left compared with right targets, and this response time

  18. Attention trees and semantic paths

    Science.gov (United States)

    Giusti, Christian; Pieroni, Goffredo G.; Pieroni, Laura

    2007-02-01

    In the last few decades several techniques for image content extraction, often based on segmentation, have been proposed. It has been suggested that under the assumption of very general image content, segmentation becomes unstable and classification becomes unreliable. According to recent psychological theories, certain image regions attract the attention of human observers more than others and, generally, the image main meaning appears concentrated in those regions. Initially, regions attracting our attention are perceived as a whole and hypotheses on their content are formulated; successively the components of those regions are carefully analyzed and a more precise interpretation is reached. It is interesting to observe that an image decomposition process performed according to these psychological visual attention theories might present advantages with respect to a traditional segmentation approach. In this paper we propose an automatic procedure generating image decomposition based on the detection of visual attention regions. A new clustering algorithm taking advantage of the Delaunay- Voronoi diagrams for achieving the decomposition target is proposed. By applying that algorithm recursively, starting from the whole image, a transformation of the image into a tree of related meaningful regions is obtained (Attention Tree). Successively, a semantic interpretation of the leaf nodes is carried out by using a structure of Neural Networks (Neural Tree) assisted by a knowledge base (Ontology Net). Starting from leaf nodes, paths toward the root node across the Attention Tree are attempted. The task of the path consists in relating the semantics of each child-parent node pair and, consequently, in merging the corresponding image regions. The relationship detected in this way between two tree nodes generates, as a result, the extension of the interpreted image area through each step of the path. The construction of several Attention Trees has been performed and partial

  19. Attention

    Science.gov (United States)

    Montessori, Maria

    2016-01-01

    "The Advanced Montessori Method, Volume 1" was published in 1918 in English and is considered a seminal work along with "The Montessori Method." In the foreword to this book, Mario Montessori writes: "...the refulgent figure of the child, Dr. Montessori pointed out, who had found his own path to mental health, who…

  20. Modelling of Attentional Dwell Time

    DEFF Research Database (Denmark)

    Petersen, Anders; Kyllingsbæk, Søren; Bundesen, Claus

    2009-01-01

    Studies of the time course of visual attention have identified a temporary functional blindness to the second of two spatially separated targets: attending to one visual stimulus may lead to impairments in identifying a second stimulus presented between 200 to 500 ms after the first. This phenome......Studies of the time course of visual attention have identified a temporary functional blindness to the second of two spatially separated targets: attending to one visual stimulus may lead to impairments in identifying a second stimulus presented between 200 to 500 ms after the first....... This phenomenon is known as attentional dwell time (e.g. Duncan, Ward, Shapiro, 1994). All Previous studies of the attentional dwell time have looked at data averaged across subjects. In contrast, we have succeeded in running subjects for 3120 trials which has given us reliable data for modelling data from...... individual subjects. Our new model is based on the Theory of Visual Attention (TVA; Bundesen, 1990). TVA has previously been successful in explaining results from experiments where stimuli are presented simultaneously in the spatial domain (e.g. whole report and partial report) but has not yet been extended...

  1. Large-scale time-lapse microscopy of Oct4 expression in human embryonic stem cell colonies.

    Science.gov (United States)

    Bhadriraju, Kiran; Halter, Michael; Amelot, Julien; Bajcsy, Peter; Chalfoun, Joe; Vandecreme, Antoine; Mallon, Barbara S; Park, Kye-Yoon; Sista, Subhash; Elliott, John T; Plant, Anne L

    2016-07-01

    Identification and quantification of the characteristics of stem cell preparations is critical for understanding stem cell biology and for the development and manufacturing of stem cell based therapies. We have developed image analysis and visualization software that allows effective use of time-lapse microscopy to provide spatial and dynamic information from large numbers of human embryonic stem cell colonies. To achieve statistically relevant sampling, we examined >680 colonies from 3 different preparations of cells over 5days each, generating a total experimental dataset of 0.9 terabyte (TB). The 0.5 Giga-pixel images at each time point were represented by multi-resolution pyramids and visualized using the Deep Zoom Javascript library extended to support viewing Giga-pixel images over time and extracting data on individual colonies. We present a methodology that enables quantification of variations in nominally-identical preparations and between colonies, correlation of colony characteristics with Oct4 expression, and identification of rare events. Copyright © 2016. Published by Elsevier B.V.

  2. Large-scale time-lapse microscopy of Oct4 expression in human embryonic stem cell colonies

    Directory of Open Access Journals (Sweden)

    Kiran Bhadriraju

    2016-07-01

    Full Text Available Identification and quantification of the characteristics of stem cell preparations is critical for understanding stem cell biology and for the development and manufacturing of stem cell based therapies. We have developed image analysis and visualization software that allows effective use of time-lapse microscopy to provide spatial and dynamic information from large numbers of human embryonic stem cell colonies. To achieve statistically relevant sampling, we examined >680 colonies from 3 different preparations of cells over 5 days each, generating a total experimental dataset of 0.9 terabyte (TB. The 0.5 Giga-pixel images at each time point were represented by multi-resolution pyramids and visualized using the Deep Zoom Javascript library extended to support viewing Giga-pixel images over time and extracting data on individual colonies. We present a methodology that enables quantification of variations in nominally-identical preparations and between colonies, correlation of colony characteristics with Oct4 expression, and identification of rare events.

  3. The Relationship between Cell Number, Division Behavior and Developmental Potential of Cleavage Stage Human Embryos: A Time-Lapse Study.

    Science.gov (United States)

    Kong, Xiangyi; Yang, Shuting; Gong, Fei; Lu, Changfu; Zhang, Shuoping; Lu, Guangxiu; Lin, Ge

    2016-01-01

    Day 3 cleavage embryo transfer is routine in many assisted reproductive technology centers today. Embryos are usually selected according to cell number, cell symmetry and fragmentation for transfer. Many studies have showed the relationship between cell number and embryo developmental potential. However, there is limited understanding of embryo division behavior and their association with embryo cell number and developmental potential. A retrospective and observational study was conducted to investigate how different division behaviors affect cell number and developmental potential of day 3 embryos by time-lapse imaging. Based on cell number at day 3, the embryos (from 104 IVF/intracytoplasmic sperm injection (ICSI) treatment cycles, n = 799) were classified as follows: less than 5 cells (10C; n = 42). Division behavior, morphokinetic parameters and blastocyst formation rate were analyzed in 5 groups of day 3 embryos with different cell numbers. In 10C embryos increased compared to 7-8C embryos (45.8%, 33.3% vs. 11.1%, respectively). In ≥5C embryos, FR and DC significantly reduced developmental potential, whereas potential irrespective of division behaviors. In NB embryos, the blastocyst formation rate increased with cell number from 7.4% (10C). In NB embryos, the cell cycle elongation or shortening was the main cause for abnormally low or high cell number, respectively. After excluding embryos with abnormal division behaviors, the developmental potential, implantation rate and live birth rate of day 3 embryos increased with cell number.

  4. Improving Snow Process Modeling with Satellite-Based Estimation of Near-Surface-Air-Temperature Lapse Rate

    Science.gov (United States)

    Wang, Lei

    2017-04-01

    In distributed hydrological modeling, surface air temperature (Tair) is of great importance in simulating cold region processes, while the near-surface-air-temperature lapse rate (NLR) is crucial to prepare Tair (when interpolating Tair from site observations to model grids). In this study, a distributed biosphere hydrological model with improved snow physics (WEB-DHM-S) was rigorously evaluated in a typical cold, large river basin (e.g., the upper Yellow River basin), given a mean monthly NLRs. Based on the validated model, we have examined the influence of the NLR on the simulated snow processes and streamflows. We found that the NLR has a large effect on the simulated streamflows, with a maximum difference of greater than 24 % among the various scenarios for NLRs considered. To supplement the insufficient number of monitoring sites for near-surface-air-temperature at developing/undeveloped mountain regions, the nighttime MODIS LST is used as an alternative to derive the approximate NLR at a finer spatial scale (e.g., at different elevation bands, different land covers, different aspects, and different snow conditions). Using satellite-based estimation of NLR, the modeling of snow processes has been greatly refined. Results show that both the determination of rainfall/snowfall and the snow pack process were significantly improved, contributing to a reduced summer evapotranspiration and thus an improved streamflow simulation.

  5. Technical note: Stage and water width measurement of a mountain stream using a simple time-lapse camera

    Directory of Open Access Journals (Sweden)

    P. Leduc

    2018-01-01

    Full Text Available Remote sensing applied to river monitoring adds complementary information useful for understanding the system behaviour. In this paper, we present a method for visual stage gauging and water surface width measurement using a ground-based time-lapse camera and a fully automatic image analysis algorithm for flow monitoring at a river cross section of a steep, bouldery channel. The remote stage measurement was coupled with a water level logger (pressure transducer on site and shows that the image-based method gives a reliable estimate of the water height variation and daily flow record when validated against the pressure transducer (R = 0.91. From the remotely sensed pictures, we also extracted the water width and show that it is possible to correlate water surface width and stage. The images also provide valuable ancillary information for interpreting and understanding flow hydraulics and site weather conditions. This image-based gauging method is a reliable, informative and inexpensive alternative or adjunct to conventional stage measurement especially for remote sites.

  6. Lapses, infidelities, and creative adaptations: lessons from evaluation of a participatory market development approach in the Andes.

    Science.gov (United States)

    Horton, Douglas; Rotondo, Emma; Paz Ybarnegaray, Rodrigo; Hareau, Guy; Devaux, André; Thiele, Graham

    2013-08-01

    Participatory approaches are frequently recommended for international development programs, but few have been evaluated. From 2007 to 2010 the Andean Change Alliance evaluated an agricultural research and development approach known as the "Participatory Market Chain Approach" (PMCA). Based on a study of four cases, this paper examines the fidelity of implementation, the factors that influenced implementation and results, and the PMCA change model. We identify three types of deviation from the intervention protocol (lapses, creative adaptations, and true infidelities) and five groups of variables that influenced PMCA implementation and results (attributes of the macro context, the market chain, the key actors, rules in use, and the capacity development strategy). There was insufficient information to test the validity of the PMCA change model, but results were greatest where the PMCA was implemented with highest fidelity. Our analysis suggests that the single most critical component of the PMCA is engagement of market agents - not just farmers - throughout the exercise. We present four lessons for planning and evaluating participatory approaches related to the use of action and change models, the importance of monitoring implementation fidelity, the limits of baseline survey data for outcome evaluation, and the importance of capacity development for implementers. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Technical note: Stage and water width measurement of a mountain stream using a simple time-lapse camera

    Science.gov (United States)

    Leduc, Pauline; Ashmore, Peter; Sjogren, Darren

    2018-01-01

    Remote sensing applied to river monitoring adds complementary information useful for understanding the system behaviour. In this paper, we present a method for visual stage gauging and water surface width measurement using a ground-based time-lapse camera and a fully automatic image analysis algorithm for flow monitoring at a river cross section of a steep, bouldery channel. The remote stage measurement was coupled with a water level logger (pressure transducer) on site and shows that the image-based method gives a reliable estimate of the water height variation and daily flow record when validated against the pressure transducer (R = 0.91). From the remotely sensed pictures, we also extracted the water width and show that it is possible to correlate water surface width and stage. The images also provide valuable ancillary information for interpreting and understanding flow hydraulics and site weather conditions. This image-based gauging method is a reliable, informative and inexpensive alternative or adjunct to conventional stage measurement especially for remote sites.

  8. Formation and spreading of TDP-43 aggregates in cultured neuronal and glial cells demonstrated by time-lapse imaging.

    Directory of Open Access Journals (Sweden)

    Tomohiro Ishii

    Full Text Available TAR DNA-binding protein 43 (TDP-43 is a main constituent of cytoplasmic aggregates in neuronal and glial cells in cases of amyotrophic lateral sclerosis and frontotemporal lobar degeneration. We have previously demonstrated that adenovirus-transduced artificial TDP-43 cytoplasmic aggregates formation is enhanced by proteasome inhibition in vitro and in vivo. However, the relationship between cytoplasmic aggregate formation and cell death remains unclear. In the present study, rat neural stem cell lines stably transfected with EGFP- or Sirius-expression vectors under the control of tubulin beta III, glial fibrillary acidic protein, or 2',3'-cyclic nucleotide 3'-phosphodiesterase promoter were differentiated into neurons, astrocytes, and oligodendrocytes, respectively, in the presence of retinoic acid. The differentiated cells were then transduced with adenoviruses expressing DsRed-tagged human wild type and C-terminal fragment TDP-43 under the condition of proteasome inhibition. Time-lapse imaging analyses revealed growing cytoplasmic aggregates in the transduced neuronal and glial cells, followed by collapse of the cell. The aggregates remained insoluble in culture media, consisted of sarkosyl-insoluble granular materials, and contained phosphorylated TDP-43. Moreover, the released aggregates were incorporated into neighboring neuronal cells, suggesting cell-to-cell spreading. The present study provides a novel tool for analyzing the detailed molecular mechanisms of TDP-43 proteinopathy in vitro.

  9. The Relationship between Cell Number, Division Behavior and Developmental Potential of Cleavage Stage Human Embryos: A Time-Lapse Study.

    Directory of Open Access Journals (Sweden)

    Xiangyi Kong

    Full Text Available Day 3 cleavage embryo transfer is routine in many assisted reproductive technology centers today. Embryos are usually selected according to cell number, cell symmetry and fragmentation for transfer. Many studies have showed the relationship between cell number and embryo developmental potential. However, there is limited understanding of embryo division behavior and their association with embryo cell number and developmental potential. A retrospective and observational study was conducted to investigate how different division behaviors affect cell number and developmental potential of day 3 embryos by time-lapse imaging. Based on cell number at day 3, the embryos (from 104 IVF/intracytoplasmic sperm injection (ICSI treatment cycles, n = 799 were classified as follows: less than 5 cells (10C; n = 42. Division behavior, morphokinetic parameters and blastocyst formation rate were analyzed in 5 groups of day 3 embryos with different cell numbers. In 10C embryos increased compared to 7-8C embryos (45.8%, 33.3% vs. 11.1%, respectively. In ≥5C embryos, FR and DC significantly reduced developmental potential, whereas 10C. In NB embryos, the cell cycle elongation or shortening was the main cause for abnormally low or high cell number, respectively. After excluding embryos with abnormal division behaviors, the developmental potential, implantation rate and live birth rate of day 3 embryos increased with cell number.

  10. A Sparse Bayesian Imaging Technique for Efficient Recovery of Reservoir Channels With Time-Lapse Seismic Measurements

    KAUST Repository

    Sana, Furrukh

    2016-06-01

    Subsurface reservoir flow channels are characterized by high-permeability values and serve as preferred pathways for fluid propagation. Accurate estimation of their geophysical structures is thus of great importance for the oil industry. The ensemble Kalman filter (EnKF) is a widely used statistical technique for estimating subsurface reservoir model parameters. However, accurate reconstruction of the subsurface geological features with the EnKF is challenging because of the limited measurements available from the wells and the smoothing effects imposed by the \\\\ell _{2} -norm nature of its update step. A new EnKF scheme based on sparse domain representation was introduced by Sana et al. (2015) to incorporate useful prior structural information in the estimation process for efficient recovery of subsurface channels. In this paper, we extend this work in two ways: 1) investigate the effects of incorporating time-lapse seismic data on the channel reconstruction; and 2) explore a Bayesian sparse reconstruction algorithm with the potential ability to reduce the computational requirements. Numerical results suggest that the performance of the new sparse Bayesian based EnKF scheme is enhanced with the availability of seismic measurements, leading to further improvement in the recovery of flow channels structures. The sparse Bayesian approach further provides a computationally efficient framework for enforcing a sparse solution, especially with the possibility of using high sparsity rates through the inclusion of seismic data.

  11. Components of Attention in Synesthesia

    DEFF Research Database (Denmark)

    Sørensen, Thomas Alrik; Nordfang, Maria; Pedersen, Michael Nygaard

    2013-01-01

    One of the most common forms of synesthesia is between colors and graphemes (Colizoli, Murre, & Rouw, 2012). Numerous studies have investigated different aspects of attention and synesthesia, e.g. effects of Stroop-like interference by colors that are incongruent with the synesthetic experience....... Here we attempt to isolate how speci¿ c components of attention are affected by grapheme-color synesthesia. Eight carefully screened healthy participants with synesthesia reported the letters in brie¿ y presented, post-masked arrays of letters and digits. On half the trials, the letters and digits were...... presented in colors congruent with the synesthetic experience. On the other half of the trials, the letters and digits were presented in colors that were incongruent with the synesthetic experience. Components of attention were estimated separately for congruent and incongruent trials by ¿ tting the data...

  12. Attention in the predictive mind.

    Science.gov (United States)

    Ransom, Madeleine; Fazelpour, Sina; Mole, Christopher

    2017-01-01

    It has recently become popular to suggest that cognition can be explained as a process of Bayesian prediction error minimization. Some advocates of this view propose that attention should be understood as the optimization of expected precisions in the prediction-error signal (Clark, 2013, 2016; Feldman & Friston, 2010; Hohwy, 2012, 2013). This proposal successfully accounts for several attention-related phenomena. We claim that it cannot account for all of them, since there are certain forms of voluntary attention that it cannot accommodate. We therefore suggest that, although the theory of Bayesian prediction error minimization introduces some powerful tools for the explanation of mental phenomena, its advocates have been wrong to claim that Bayesian prediction error minimization is 'all the brain ever does'. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Supramodal Executive Control of Attention

    Directory of Open Access Journals (Sweden)

    ALFREDO eSPAGNA

    2015-02-01

    Full Text Available The human attentional system can be subdivided into three functional networks of alerting, orienting, and executive control. Although these networks have been extensively studied in the visuospatial modality, whether the same mechanisms are deployed across different sensory modalities remains unclear. In this study we used the attention network test for visuospatial modality, in addition to two auditory variants with spatial and frequency manipulations to examine cross-modal correlations between network functions. Results showed that among the visual and auditory tasks the effects of executive control, but not effects of alerting and orienting were significantly correlated. These findings suggest that while alerting and orienting functions rely more upon modality specific processes, the executive control of attention coordinates complex behavior via supramodal mechanisms.

  14. Chewing and Attention: A Positive Effect on Sustained Attention

    National Research Council Canada - National Science Library

    Hirano, Yoshiyuki; Onozuka, Minoru

    2015-01-01

    .... These findings support the concept that chewing is strongly associated with cognitive function such as learning and memory and keeping and increasing attention [5]. This relationship between chewing and cognitive functions was empirically estimated a long time ago. In 1939, Hollingworth [6] reported that chewing increased relaxation and the performance of cognitive ...

  15. Capture of exogenous attention modulates the attentional blink

    DEFF Research Database (Denmark)

    Nielsen, Simon; Andersen, Tobias

    2011-01-01

    When two targets (T1 & T2) are presented in rapid succession, observers often fail to report T2 if they attend to T1. Bottleneck theories propose that this attentional blink (AB) is due to T1 occupying a slow processing stage when T2 is presented. Accordingly, if increasing T1 difficulty increases...

  16. Capture of exogenous attention modulates the attentional blink

    DEFF Research Database (Denmark)

    Nielsen, Simon; Andersen, Tobias

    2011-01-01

    When two targets (T1 & T2) are presented in rapid succession, observers often fail to report T2 if they attend to T1. Bottleneck theories propose that this attentional blink (AB) is due to T1 occupying a slow processing stage when T2 is presented. Accordingly, if increasing T1 difficulty increase...

  17. Mindful Movement and Skilled Attention

    Directory of Open Access Journals (Sweden)

    Dav eClark

    2015-06-01

    Full Text Available Bodily movement has long been employed as a foundation for cultivating mental skills such as attention, self-control or mindfulness, with recent studies documenting the positive impacts of mindful movement training, such as yoga and tai chi. A parallel mind-body connection has also been observed in many developmental disorders. We elaborate a spectrum of mindfulness by considering ADHD, in which deficient motor control correlates with impaired (disinhibited behavioral control contributing to defining features of excessive distractibility and impulsivity. These data provide evidence for an important axis of variation for wellbeing, in which skillful cognitive control covaries with a capacity for skillful movement. We review empirical and theoretical literature on attention, cognitive control, mind wandering, mindfulness and skill learning, endorsing a model of skilled attention in which motor plans, attention, and executive goals are seen as mutually co-defining aspects of skilled behavior that are linked by reciprocal inhibitory and excitatory connections. Thus, any movement training should engage higher-order inhibition and selection and develop a repertoire of rehearsed procedures that coordinate goals, attention and motor plans. However, we propose that mindful movement practice may improve the functional quality of rehearsed procedures, cultivating a transferrable skill of attention. We adopt Langer’s spectrum of mindful learning that spans from mindlessness to engagement with the details of the present task and contrast this with the mental attitudes cultivated in standard mindfulness meditation. We particularly follow Feldenkrais’ suggestion that mindful learning of skills for organizing the body in movement might transfer to other forms of mental activity. The results of mindful movement training should be observed in multiple complementary measures, and may have tremendous potential benefit for individuals with ADHD and other

  18. Mindful movement and skilled attention.

    Science.gov (United States)

    Clark, Dav; Schumann, Frank; Mostofsky, Stewart H

    2015-01-01

    Bodily movement has long been employed as a foundation for cultivating mental skills such as attention, self-control or mindfulness, with recent studies documenting the positive impacts of mindful movement training, such as yoga and tai chi. A parallel "mind-body connection" has also been observed in many developmental disorders. We elaborate a spectrum of mindfulness by considering ADHD, in which deficient motor control correlates with impaired (disinhibited) behavioral control contributing to defining features of excessive distractibility and impulsivity. These data provide evidence for an important axis of variation for wellbeing, in which skillful cognitive control covaries with a capacity for skillful movement. We review empirical and theoretical literature on attention, cognitive control, mind wandering, mindfulness and skill learning, endorsing a model of skilled attention in which motor plans, attention, and executive goals are seen as mutually co-defining aspects of skilled behavior that are linked by reciprocal inhibitory and excitatory connections. Thus, any movement training should engage "higher-order" inhibition and selection and develop a repertoire of rehearsed procedures that coordinate goals, attention and motor plans. However, we propose that mindful movement practice may improve the functional quality of rehearsed procedures, cultivating a transferrable skill of attention. We adopt Langer's spectrum of mindful learning that spans from "mindlessness" to engagement with the details of the present task and contrast this with the mental attitudes cultivated in standard mindfulness meditation. We particularly follow Feldenkrais' suggestion that mindful learning of skills for organizing the body in movement might transfer to other forms of mental activity. The results of mindful movement training should be observed in multiple complementary measures, and may have tremendous potential benefit for individuals with ADHD and other populations.

  19. Hillslope-scale hydrological and snow cover dynamics derived from a wireless soil moisture and temperature monitoring network and time-lapse digital photography

    Science.gov (United States)

    Wollschläger, Ute; Vogt, Constantin; Kögler, Simon; Martini, Edoardo

    2015-04-01

    In mountainous catchments, snowmelt may be an important component of the water balance. We apply data from a wireless soil moisture and temperature monitoring network in combination with time-lapse digital photographs from a hillslope in the Schäfertal catchment, Lower Harz Mountains, to investigate interactions between hillslope-scale snow cover, soil moisture and soil temperature. The time series of digital photographs is evaluated using an automatic algorithm that estimates snow height at the position of several snow stakes placed along the hillslope using the green value of the RGB color cube. Inferred snow heights are applied to interpret near-subsurface soil moisture and soil temperature dynamics from the same time period including snow accumulation and melt. The combination of time-lapse digital photography, soil moisture and soil temperature monitoring clearly shows the strong influence of the snow cover on subsurface soil moisture and soil temperature dynamics. The shallow snow cover has a strong insulating effect on near-subsurface soil temperatures keeping the soil unfrozen even at air temperatures reaching down to less than -10 °C. The time-lapse photographs, soil moisture and soil temperature observations also show the different snowmelt behavior of the north- and south-exposed slopes. These observations are important information for future modelling of hillslope and catchment-scale hydrological dynamics.

  20. Attention as foraging for information and reward

    National Research Council Canada - National Science Library

    Sanjay G Manohar; Masud eHusain

    2013-01-01

    What is the purpose of attention? One avenue of research has led to the proposal that attention might be crucial for gathering information about the environment, while other lines of study have demonstrated attention's role...

  1. Attention as foraging for information and value

    National Research Council Canada - National Science Library

    Manohar, Sanjay G; Husain, Masud

    2013-01-01

    What is the purpose of attention? One avenue of research has led to the proposal that attention might be crucial for gathering information about the environment, while other lines of study have demonstrated how attention may play...

  2. Attention Deficit Hyperactivity Disorder (ADHD)

    Centers for Disease Control (CDC) Podcasts

    2014-04-10

    This podcast discusses Attention Deficit Hyperactivity Disorder, or ADHD, the most common behavioral disorder in children. Learn about symptoms, risk factors, and treatment.  Created: 4/10/2014 by National Center on Birth Defects and Developmental Disabilities (NCBDDD).   Date Released: 5/7/2014.

  3. Donor attention to reading materials.

    Science.gov (United States)

    O'Brien, S F; Osmond, L; Choquet, K; Yi, Q-L; Goldman, M

    2015-11-01

    Mandatory predonation reading materials inform donors about risk factors for transmissible disease, possible complications of donation and changes to the donation process. We aimed to assess the attention to predonation reading materials and factors which may affect attention. A national survey in 2008 of 18,108 blood donors asked about self-assessed attention to reading the materials. In face-to-face interviews, 441 donors completed additional questions about reading the materials and a literacy test. Qualitative interviews of 27 donors assessed their approach to reading. In the national survey, most of the first-time donors said they read all or most of the materials (90.9% first-time vs. 57.6% repeat donors, P reading them carefully (P read materials carefully, skimmed or did not read, most knew that donors are informed of positive transmissible disease test results (97.1%, 95.5, 98.0 P > 0.05), but fewer recalled seeing the definition of sex (77.2%, 56.9, 24.2 P read materials carefully, skimmed or did not read were compared (P > 0.05). Qualitative interviews showed that donors are reluctant to read any more than necessary and decide based on perceived importance or relevance. Attention to predonation reading materials tends to be better among first-time donors. The effectiveness is limited by low motivation to read, especially for repeat donors, as well as poor literacy. © 2015 International Society of Blood Transfusion.

  4. Attentional Capture in Driving Displays

    Science.gov (United States)

    Arexis, Mahé; Maquestiaux, François; Gaspelin, Nicholas; Ruthruff, Eric; Didierjean, André

    2016-01-01

    Drivers face frequent distraction on the roadways but little is known about situations placing them at risk of misallocating visual attention. To investigate this issue, we asked participants to search for a red target embedded within simulated driving scenes (photographs taken from inside a car) in three experiments. Distraction was induced by presenting, via a GPS unit, red or green distractors positioned in an irrelevant location at which the target never appeared. If the salient distractor captures attention, visual search should be slower on distractor-present trials than distractor-absent trials. In Experiment 1, salient distractors yielded no such capture effect. In Experiment 2, we decreased the frequency of the salient distractor from 50% of trials to only 10% or 20% of trials. Capture effects were almost five times larger for the 10% occurrence group than for the 20% occurrence group. In Experiment 3, the amount of available central resources was manipulated by asking participants to either simultaneously monitor or ignore a stream of spoken digits. Capture effects were much larger for the dual-task group than for the single-task group. In summary, these findings identify risk factors for attentional capture in real-world driving scenes: distractor rarity and diversion of attention. PMID:28369841

  5. Deployment of Attention on Handshakes.

    Science.gov (United States)

    Shen, Mowei; Yin, Jun; Ding, Xiaowei; Shui, Rende; Zhou, Jifan

    2016-01-01

    Understanding the social structures between objects, organizing, and selecting them accordingly, is fundamental to social cognition. We report an example that demonstrates the object association learned from social interactions could impact visual attention. Particularly, when two hands approach each other to perform a handshake, they tend to be attended to as a unit because of the cooperative relationship exhibited in the action: even a cue presented on a non-target hand may facilitate a response to the targets that appear on the non-cued hand (Experiment 1), indicating that attentional shift between two hands was facilitated; furthermore, the response to a target on one hand is significantly impaired by a distractor on the other hand (Experiment 2), implying that it is difficult to selectively confine attention to a single hand. These effects were dependent on the existence of the hands when cue and target appeared (Experiment 3); neither perceptual familiarity, or physical fit can explain all the attention effects (Experiment 4). These results have bearings on the perceptual root of social cognition.

  6. Attentional Bias in Math Anxiety

    Directory of Open Access Journals (Sweden)

    Orly eRubinsten

    2015-10-01

    Full Text Available Cognitive theory from the field of general anxiety suggests that the tendency to display attentional bias toward negative information results in anxiety. Accordingly, the current study aims to investigate whether attentional bias is involved in math anxiety as well (i.e., a persistent negative reaction to math. Twenty seven participants (14 with high levels of math anxiety and 13 with low levels of math anxiety were presented with a novel computerized numerical version of the well established dot probe task. One of 6 types of prime stimuli, either math related or typically neutral, were presented on one side of a computer screen. The prime was preceded by a probe (either one or two asterisks that appeared in either the prime or the opposite location. Participants had to discriminate probe identity (one or two asterisks. Math anxious individuals reacted faster when the probe was at the location of the numerical related stimuli. This suggests the existence of attentional bias in math anxiety. That is, for math anxious individuals, the cognitive system selectively favored the processing of emotionally negative information (i.e., math related words. These findings suggest that attentional bias is linked to unduly intense math anxiety symptoms.

  7. Joint Attention and Anthropological Difference

    Czech Academy of Sciences Publication Activity Database

    Urban, Petr

    2014-01-01

    Roč. 11, č. 1 (2014), s. 59-70 ISSN 1718-0198 R&D Projects: GA ČR GAP401/10/1164 Institutional support: RVO:67985955 Keywords : joint attention * anthropological difference * phenomenology * great apes * shared intentionality Subject RIV: AA - Philosophy ; Religion

  8. Attention: A Machine Learning Perspective

    DEFF Research Database (Denmark)

    Hansen, Lars Kai

    2012-01-01

    We review a statistical machine learning model of top-down task driven attention based on the notion of ‘gist’. In this framework we consider the task to be represented as a classification problem with two sets of features — a gist of coarse grained global features and a larger set of low...

  9. Dyscalculia and Attention Deficit Subtypes

    OpenAIRE

    J Gordon Millichap

    1999-01-01

    The association of specific academic deficits with attention deficit disorder (ADD) subtypes was determined in 20 students (ages 8-12) with ADD with hyperactivity (ADD/H) compared to 20 with ADD without hyperactivity (ADD/noH), at the Department of Educational Psychology, University of Texas at Austin, TX.

  10. Attention Deficit and EEG Analysis

    OpenAIRE

    J Gordon Millichap

    1992-01-01

    Computerized power spectral analysis (PSA), permitting topographic representation and statistical analysis of EEG, of 25 right-handed males, 9-12 years of age with attention deficit hyperactivity disorder was used in studies from the Departments of Psychology, Pediatrics (Neurology) and Computing Center, University of Tennessee and East Tennessee Children’s Hospital, Knoxville, TN.

  11. Practicing the attentional Dwell Away?

    DEFF Research Database (Denmark)

    Petersen, Anders; Kyllingsbæk, Søren; Bundesen, Claus Mogens

    2007-01-01

    Studies of the time course of visual attention have identified a temporary functional blindness to the second of two spatially separated targets: attending to one visual stimulus may lead to impairments in identifying a second stimulus presented about 200-500 ms later than the first. The phenomen...... the task....

  12. Attention and the Testing Effect

    Science.gov (United States)

    Mulligan, Neil W.; Picklesimer, Milton

    2016-01-01

    Memory retrieval often enhances still later memory as evidenced by the testing effect. Divided attention (DA) is known to produce different effects on encoding and retrieval, substantially disrupting the former and often producing little effect on the latter. The present experiments examine whether the mnemonic consequences of retrieval are…

  13. Perception and Attention for Visualization

    Science.gov (United States)

    Haroz, Steve

    2013-01-01

    This work examines how a better understanding of visual perception and attention can impact visualization design. In a collection of studies, I explore how different levels of the visual system can measurably affect a variety of visualization metrics. The results show that expert preference, user performance, and even computational performance are…

  14. [Selective visual attention and simultanagnosia].

    Science.gov (United States)

    Suzuki, K

    2001-12-01

    The parietal lobe is an important key station in the network for selective attention. We found that spontaneous shift of visual attention, depending on task requirement, was impaired by parietal lobe lesions and confirmed the relationship between parietal lobes and visual attention with cortical electric stimulation. Patient 1. A 52-year-old, right-handed carpenter with a diagnosis of 'visual form' of Alzheimer disease showed marked kanji (logogram) agraphia and constructional impairment. Cerebral atrophy and hypoperfusion were observed in bilateral parietal lobes. He showed preserved form and color perception and an ability to describe spatial relationship among several items. In contrast, he could not copy or match them. He seemed to look at only the site he was drawing. Patient 2. A 77-year-old man with cerebral infarction in bilateral parietal lobes and right frontotemporal areas, demonstrated simultanagnosia and visuomotor ataxia. He readily named an object but could not describe a scene. Furthermore he noticed a line between sentences when they were written in English, but could not notice a line when sentences were written in Japanese. Cortical electric mapping, in two patients with subdural electrodes on the left or right parietal lobe, revealed circumscribed regions related to global/local attention shift or line bisection tasks.

  15. Mood, eating behaviour and attention.

    Science.gov (United States)

    Williams, J M G; Healy, H; Eade, J; Windle, G; Cowen, P J; Green, M W; Durlach, P

    2002-04-01

    Obesity is a growing health problem, but most people find dieting unsuccessful. Three studies examine possible reasons for the difficulty and the extent to which dieting-related reductions in cognitive function are associated with mood and well-being. In Study One, 49 female dieters were compared with a control group of 31 matched non-dieters on measures of well-being, mood, eating behaviour (Dutch Eating Behaviour Questionnaire), and attention. Study Two examined two measures of restraint to examine why previous studies find high restrainers are prone to react to emotion. Study Three experimentally manipulated mood using music and the standard Velten Induction Procedure to examine attention in restrainers and emotional eaters. Dieting was found to be associated with deficits in sustained attention. This finding was further supported by the demonstration of a significant impairment in performance following a negative mood induction in high emotional eaters whereas high restrainers were relatively unaffected by the mood challenge. We suggest that different aspects of eating behaviour have dissociable effects on cognitive-affective function. Trait tendencies to restrained eating are associated with attentional deficits, but are not further affected by mood disruption. It is the long-term tendency to eat when emotional that combines with current emotional state to trigger cognitive deficits.

  16. Regularized focusing inversion of time-lapse electrical resistivity data: an approach to parametrize the minimum gradient support functional

    Science.gov (United States)

    Nguyen, Frédéric; Hermans, Thomas

    2015-04-01

    Inversion of time-lapse resistivity data allows obtaining 'snapshots' of changes occurring in monitored systems for applications such as aquifer storage, geothermal heat exchange, site remediation or tracer tests. Based on these snapshots, one can infer qualitative information on the location and morphology of changes occurring in the subsurface but also quantitative estimates on the degree of changes in certain property such as temperature or total dissolved solid content. Analysis of these changes can provide direct insight into flow and transport and associated processes and controlling parameters. However, the reliability of the analysis is dependent on survey geometry, measurement schemes, data error, and regularization. Survey design parameters may be optimized prior to the monitoring survey. Regularization, on the other hand, may be chosen depending on available information collected during the monitoring. Common approaches consider smoothing model changes both in space and time but it is often needed to obtain a sharp temporal anomaly, for example in fractured aquifers. We here propose to use the alternative regularization approach based on minimum gradient support (MGS) (Zhdanov, 2002) for time-lapse surveys which will focus the changes in tomograms snapshots. MGS will limit the occurrences of changes in electrical resistivity but will also restrict the variations of these changes inside the different zones. A commonly encountered difficulty by practitioners in this type of regularization is the choice of an additional parameter, the so-called β, required to define the MGS functional. To the best of our knowledge, there is no commonly accepted or standard methodology to optimize the MGS parameter β. The inversion algorithm used in this study is CRTomo (Kemna 2000). It uses a Gauss-Newton scheme to iteratively minimize an objective function which consists of a data misfit functional and a model constraint functional. A univariate line search is performed

  17. Visual attention: The past 25 years

    Science.gov (United States)

    Carrasco, Marisa

    2012-01-01

    This review focuses on covert attention and how it alters early vision. I explain why attention is considered a selective process, the constructs of covert attention, spatial endogenous and exogenous attention, and feature-based attention. I explain how in the last 25 years research on attention has characterized the effects of covert attention on spatial filters and how attention influences the selection of stimuli of interest. This review includes the effects of spatial attention on discriminability and appearance in tasks mediated by contrast sensitivity and spatial resolution; the effects of feature-based attention on basic visual processes, and a comparison of the effects of spatial and feature-based attention. The emphasis of this review is on psychophysical studies, but relevant electrophysiological and neuroimaging studies and models regarding how and where neuronal responses are modulated are also discussed. PMID:21549742

  18. Towards a trust and attention based management concept : paying attention to attention first

    NARCIS (Netherlands)

    Marco Oteman; Henny van Lienden

    2014-01-01

    Last year in Klagenfurt a poster was presented, in which a first attempt was made to combine institutional economic theory with organizational theory under the motto: transaction costs can be influenced! A framework of 4 theories was constructed of Social Capital theory, Attention Theory, Proactive

  19. Paying attention to attention: evidence for an attentional contribution to the size congruity effect.

    Science.gov (United States)

    Risko, Evan F; Maloney, Erin A; Fugelsang, Jonathan A

    2013-08-01

    Understanding the mechanisms supporting our comprehension of magnitude information represents a key goal in cognitive psychology. A major phenomenon employed in the pursuit of this goal has been the physical size congruity effect-namely, the observation that comparing the relative numerical sizes of two numbers is influenced by their relative physical sizes. The standard account of the physical size congruity effect attributes it to the automatic influence of the comparison of irrelevant physical magnitudes on numerical judgments. Here we develop an alternative account of this effect on the basis of the operation of attention in the typical size congruity display and the temporal dynamics of number comparison. We also provide a test of a number of predictions derived from this alternative account by combining a physical size congruity manipulation with a manipulation designed to alter the operation of attention within the typical size congruity display (i.e., a manipulation of the relative onsets of the digits). This test provides evidence consistent with an attentional contribution to the size congruity effect. Implications for our understanding of magnitude and the interactions between attention and magnitude are discussed.

  20. AnimalFinder: A semi-automated system for animal detection in time-lapse camera trap images

    Science.gov (United States)

    Price Tack, Jennifer L.; West, Brian S.; McGowan, Conor P.; Ditchkoff, Stephen S.; Reeves, Stanley J.; Keever, Allison; Grand, James B.

    2017-01-01

    Although the use of camera traps in wildlife management is well established, technologies to automate image processing have been much slower in development, despite their potential to drastically reduce personnel time and cost required to review photos. We developed AnimalFinder in MATLAB® to identify animal presence in time-lapse camera trap images by comparing individual photos to all images contained within the subset of images (i.e. photos from the same survey and site), with some manual processing required to remove false positives and collect other relevant data (species, sex, etc.). We tested AnimalFinder on a set of camera trap images and compared the presence/absence results with manual-only review with white-tailed deer (Odocoileus virginianus), wild pigs (Sus scrofa), and raccoons (Procyon lotor). We compared abundance estimates, model rankings, and coefficient estimates of detection and abundance for white-tailed deer using N-mixture models. AnimalFinder performance varied depending on a threshold value that affects program sensitivity to frequently occurring pixels in a series of images. Higher threshold values led to fewer false negatives (missed deer images) but increased manual processing time, but even at the highest threshold value, the program reduced the images requiring manual review by ~40% and correctly identified >90% of deer, raccoon, and wild pig images. Estimates of white-tailed deer were similar between AnimalFinder and the manual-only method (~1–2 deer difference, depending on the model), as were model rankings and coefficient estimates. Our results show that the program significantly reduced data processing time and may increase efficiency of camera trapping surveys.

  1. Single-cell time-lapse analysis of depletion of the universally conserved essential protein YgjD

    Directory of Open Access Journals (Sweden)

    Ackermann Martin

    2011-05-01

    Full Text Available Abstract Background The essential Escherichia coli gene ygjD belongs to a universally conserved group of genes whose function has been the focus of a number of recent studies. Here, we put ygjD under control of an inducible promoter, and used time-lapse microscopy and single cell analysis to investigate the phenotypic consequences of the depletion of YgjD protein from growing cells. Results We show that loss of YgjD leads to a marked decrease in cell size and termination of cell division. The transition towards smaller size occurs in a controlled manner: cell elongation and cell division remain coupled, but cell size at division decreases. We also find evidence that depletion of YgjD leads to the synthesis of the intracellular signaling molecule (pppGpp, inducing a cellular reaction resembling the stringent response. Concomitant deletion of the relA and spoT genes - leading to a strain that is uncapable of synthesizing (pppGpp - abrogates the decrease in cell size, but does not prevent termination of cell division upon YgjD depletion. Conclusions Depletion of YgjD protein from growing cells leads to a decrease in cell size that is contingent on (pppGpp, and to a termination of cell division. The combination of single-cell timelapse microscopy and statistical analysis can give detailed insights into the phenotypic consequences of the loss of essential genes, and can thus serve as a new tool to study the function of essential genes.

  2. Combined time-lapse magnetic resonance imaging and modeling to investigate colloid deposition and transport in porous media.

    Science.gov (United States)

    Lehoux, Alizée P; Faure, Pamela; Lafolie, François; Rodts, Stéphane; Courtier-Murias, Denis; Coussot, Philippe; Michel, Eric

    2017-10-15

    Colloidal particles can act as vectors of adsorbed pollutants in the subsurface, or be themselves pollutants. They can reach the aquifer and impair groundwater quality. The mechanisms of colloid transport and deposition are often studied in columns filled with saturated porous media. Time-lapse profiles of colloid concentration inside the columns have occasionally been derived from magnetic resonance imaging (MRI) data recorded in transport experiments. These profiles are valuable, in addition to particle breakthrough curves (BTCs), for testing and improving colloid transport models. We show that concentrations could not be simply computed from MRI data when both deposited and suspended colloids contributed to the signal. We propose a generic method whereby these data can still be used to quantitatively appraise colloid transport models. It uses the modeled suspended and deposited particle concentrations to compute modeled MRI data that are compared to the experimental data. We tested this method by performing transport experiments with sorbing colloids in sand, and assessed for the first time the capacity of the model calibrated from BTCs to reproduce the MRI data. Interestingly, the dispersion coefficient and deposition rate calibrated from the BTC were respectively overestimated and underestimated compared with those calibrated from the MRI data, suggesting that these quantities, when determined from BTCs, need to be interpreted with care. In a broader perspective, we consider that combining MRI and modeling offers great potential for the quantitative analysis of complex MRI data recorded during transport experiments in complex environmentally relevant porous media, and can help improve our understanding of the fate of colloids and solutes, first in these media, and later in soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. PFLOTRAN-E4D: A parallel open source PFLOTRAN module for simulating time-lapse electrical resistivity data

    Science.gov (United States)

    Johnson, Timothy C.; Hammond, Glenn E.; Chen, Xingyuan

    2017-02-01

    Time-lapse electrical resistivity tomography (ERT) is finding increased application for remotely monitoring processes occurring in the near subsurface in three-dimensions (i.e. 4D monitoring). However, there are few codes capable of simulating the evolution of subsurface resistivity and corresponding tomographic measurements arising from a particular process, particularly in parallel and with an open source license. Herein we describe and demonstrate an electrical resistivity tomography module for the PFLOTRAN subsurface flow and reactive transport simulation code, named PFLOTRAN-E4D. The PFLOTRAN-E4D module operates in parallel using a dedicated set of compute cores in a master-slave configuration. At each time step, the master processes receives subsurface states from PFLOTRAN, converts those states to bulk electrical conductivity, and instructs the slave processes to simulate a tomographic data set. The resulting multi-physics simulation capability enables accurate feasibility studies for ERT imaging, the identification of the ERT signatures that are unique to a given process, and facilitates the joint inversion of ERT data with hydrogeological data for subsurface characterization. PFLOTRAN-E4D is demonstrated herein using a field study of stage-driven groundwater/river water interaction ERT monitoring along the Columbia River, Washington, USA. Results demonstrate the complex nature of subsurface electrical conductivity changes, in both the saturated and unsaturated zones, arising from river stage fluctuations and associated river water intrusion into the aquifer. The results also demonstrate the sensitivity of surface based ERT measurements to those changes over time. PFLOTRAN-E4D is available with the PFLOTRAN development version with an open-source license at https://bitbucket.org/pflotran/pflotran-dev.

  4. ViCAR: An Adaptive and Landmark-Free Registration of Time Lapse Image Data from Microfluidics Experiments.

    Science.gov (United States)

    Hattab, Georges; Schlüter, Jan-Philip; Becker, Anke; Nattkemper, Tim W

    2017-01-01

    In order to understand gene function in bacterial life cycles, time lapse bioimaging is applied in combination with different marker protocols in so called microfluidics chambers (i.e., a multi-well plate). In one experiment, a series of T images is recorded for one visual field, with a pixel resolution of 60 nm/px. Any (semi-)automatic analysis of the data is hampered by a strong image noise, low contrast and, last but not least, considerable irregular shifts during the acquisition. Image registration corrects such shifts enabling next steps of the analysis (e.g., feature extraction or tracking). Image alignment faces two obstacles in this microscopic context: (a) highly dynamic structural changes in the sample (i.e., colony growth) and (b) an individual data set-specific sample environment which makes the application of landmarks-based alignments almost impossible. We present a computational image registration solution, we refer to as ViCAR: (Vi)sual (C)ues based (A)daptive (R)egistration, for such microfluidics experiments, consisting of (1) the detection of particular polygons (outlined and segmented ones, referred to as visual cues), (2) the adaptive retrieval of three coordinates throughout different sets of frames, and finally (3) an image registration based on the relation of these points correcting both rotation and translation. We tested ViCAR with different data sets and have found that it provides an effective spatial alignment thereby paving the way to extract temporal features pertinent to each resulting bacterial colony. By using ViCAR, we achieved an image registration with 99.9% of image closeness, based on the average rmsd of 4.10-2 pixels, and superior results compared to a state of the art algorithm.

  5. Documentation of normal and leukemic myelopoietic progenitor cells with high-resolution phase-contrast time-lapse cinematography.

    Science.gov (United States)

    Boll, I T

    2001-08-01

    The high-resolution phase-contrast, time-lapse cinematography using oil immersion lenses and 16-mm film demonstrates the kinetic cell events as maturation, locomotion, mitosis, and apoptosis of cells cultivated at 37 degrees C for up to 10 days. 0.5 v/v frozen-thawed sera with presumably high cytokine concentrations were added to the plasma or agar clot. Vital progenitor cells from human bone marrow and blood have a large, bright, unstructured nucleus with a large nucleolus and a narrow rim of cytoplasm (nuclear/cytoplasmic volume ratio = 0.7). Their nuclei are 6-14 micrometer in diameter and double their volume within 8 h. Many (70%) move at a mean speed of 2 micrometer/min, and many (30%) multiply with alpha-2alpha mitoses, generating progenitor cell families. Various disturbances during the course of mitosis lead to the formation of polyploid cells, thereby yielding the megakaryocytic cell line. Some of the progenitor cells undergo asymmetric alpha-alphan mitoses: One of the two initially identical daughter cells remains a progenitor cell in the morphological sense, whereas the other daughter cell - depending on the size of its mother cell - matures in the same culture medium to form a granulocytopoietic, monocytopoietic or erythrocytopoietic cell line. - In acute myeloid leukemias (AML), the blasts and their nuclei are slightly larger than the corresponding progenitor cells and move faster (5 micrometer/min). Symmetric alpha-2alpha mitoses permit unlimited multiplication of the leukemic blasts if contact with cytotoxic lymphocytes does not render them apoptotic. This results in more stromal cells than normal. Granulocytopenia, monocytopenia, and anemia occur due to the genetic impairment of signaling control for asymmetric alpha-alphan mitoses, and thrombocytopenia occurs due to the reduction in polyploidization. Copyright 2001 S. Karger GmbH, Freiburg

  6. Water content dynamics at plot scale - comparison of time-lapse electrical resistivity tomography monitoring and pore pressure modelling

    Science.gov (United States)

    Zieher, Thomas; Markart, Gerhard; Ottowitz, David; Römer, Alexander; Rutzinger, Martin; Meißl, Gertraud; Geitner, Clemens

    2017-01-01

    Physically-based dynamic modelling of shallow landslide susceptibility rests on several assumptions and simplifications. However, the applicability of physically-based models is only rarely tested in the field at the appropriate scale. This paper presents results of a spray irrigation experiment conducted on a plot of 100 m2 on an Alpine slope susceptible to shallow landsliding. Infiltrating precipitation applied at a constant rate (27.5 mm/h for 5.3 h) was monitored by means of 2D time-lapse electrical resistivity tomography, combined with time-domain reflectometry sensors installed at various depths. In addition, regolith characteristics were assessed by dynamic cone penetration tests using a light-weight cone penetrometer. The spray irrigation experiment resulted in a vertically progressing wetting front to a depth of 80-100 cm. Below that, the unconsolidated material was already saturated by rainfall in the previous days. The observed mean resistivity reduction attributed to infiltrating water during irrigation was scaled to pressure head. Mean variations in pore pressure were reproduced by a linear diffusion model also used in physically-based dynamic landslide susceptibility modelling. Sensitive parameters (hydraulic conductivity and specific storage) were tested over selected value ranges and calibrated. Calibrated parameter values are within published and experimentally derived ranges. The results of the comparison of observations and model results suggest that the model is capable of reproducing mean changes of pore pressure at a suitable scale for physically-based modelling of shallow landslide susceptibility. However, small-scale variations in pore pressure that may facilitate the triggering of shallow landslides are not captured by the model.

  7. In vivo time-lapse imaging of skin burn wound healing using second-harmonic generation microscopy

    Science.gov (United States)

    Yasui, Takeshi; Tanaka, Ryosuke; Hase, Eiji; Fukushima, Shu-ichiro; Araki, Tsutomu

    2014-02-01

    Wound healing is a process to repair the damaged tissue caused by thermal burn, incised wound, or stab wound. Although the wound healing has many aspects, it is common for dynamics of collagen fiber, such as decomposition, production, or growth, to be closely related with wound healing. If such the healing process can be visualized as a timelapse image of the collagen fiber in the same subject, one may obtain new findings regarding biological repairing mechanisms in the healing process. In this article, to investigate the temporal modoification of dermal collagen fiber in the burn wound healing, we used second-harmonic-generation (SHG) microscopy, showing high selectivity and good image contrast to collagen molecules as well as high spatial resolution, optical three-dimensional sectioning, minimal invasiveness, deep penetration, the absence of interference from background light, and in vivo measurement without additional staining. Since SHG light arises from a non-centrosymmetric triple helix of three polypeptide chains in the collagen molecule, SHG intensity sensitively reflects the structure maturity of collagen molecule and its aggregates. A series of time-lapse SHG images during the wound healing process of 2 weeks clearly indicated that condensation and melting of dermal collagen fibers by the deep dermal burn, decomposition of the damaged collagen fibers in the inflammation phase, production of new collagen fibers in the proliferation phase, and the growth of the new collagen fibers in the remodeling phase. These results show a high potential of SHG microscopy for optical assessment of the wound healing process in vivo.

  8. Is there any correlation between oocyte polarization microscopy findings with embryo time lapse monitoring in ICSI program?

    Science.gov (United States)

    Faramarzi, Azita; Khalili, Mohammad Ali; Agha-Rahimi, Azam; Omidi, Marjan

    2017-06-01

    The aim was to investigate the relationship between the presence of the meiotic spindle (MS) and zona pellucida (ZP) birefringence of MII oocytes with morphokinetics variables of derived embryos in ICSI setting. Using a polarization imaging system, the ZP birefringence and presence of MS were evaluated pre ICSI. Also, morphokinetics variables including time of second PB extrusion (tPB2), time of pronuclei appearance (tPNa), time of pronuclei fading (tPNf), time of two to eight discrete cells (t2-t8) ECC1 (t2-tPB2), cc2a (t3-t2), S2 (t4-t3) and S3 (t8-t5) as well as irregular cleavage events of 368 embryos were analyzed with time lapse monitoring (TLM). t5 occurred earlier in high birefringent ZP (HB-ZP) compared with low birefringent oocytes (LB-ZP; p = 0.001). In addition, t2 happened later in invisible MS compared to visible MS oocytes (p = 0.013). There were significantly lower rates of cell fusion (Fu) in oocytes with HB-ZP and also the Fu and trichotomous mitoses (TM) together in visible MS oocytes (p = 0.005, p = 0.001 and p = 0.001, respectively). Both t2 and t5 timings and irregular cleavage events of embryos were correlated with ZP birefringence and MS status, respectively. So, combining the information from both oocyte polarization microscopy imaging and embryo TLM can be a useful tool for single embryo transfer (SET) program.

  9. Application of time-lapse ERT to Characterize Soil-Water-Disease Interactions of Citrus Orchard - Case Study

    Science.gov (United States)

    Peddinti, S. R.; Kbvn, D. P.; Ranjan, S.; Suradhaniwar, S.; J, P. A.; R M, G.

    2015-12-01

    Vidarbha region in Maharashtra, India (home for mandarin Orange) experience severe climatic uncertainties resulting in crop failure. Phytopthora are the soil-borne fungal species that accumulate in the presence of moisture, and attack the root / trunk system of Orange trees at any stage. A scientific understanding of soil-moisture-disease relations within the active root zone under different climatic, irrigation, and crop cycle conditions can help in practicing management activities for improved crop yield. In this study, we developed a protocol for performing 3-D time-lapse electrical resistivity tomography (ERT) at micro scale resolution to monitor the changes in resistivity distribution within the root zone of Orange trees. A total of 40 electrodes, forming a grid of 3.5 m x 2 m around each Orange tree were used in ERT survey with gradient and Wenner configurations. A laboratory test on un-disturbed soil samples of the region was performed to plot the variation of electrical conductivity with saturation. Curve fitting techniques were applied to get the modified Archie's model parameters. The calibrated model was further applied to generate the 3-D soil moisture profiles of the study area. The point estimates of soil moisture were validated using TDR probe measurements at 3 different depths (10, 20, and 40 cm) near to the root zone. In order to understand the effect of soil-water relations on plant-disease relations, we performed ERT analysis at two locations, one at healthy and other at Phytopthora affected Orange tree during the crop cycle, under dry and irrigated conditions. The degree to which an Orange tree is affected by Phytopthora under each condition is evaluated using 'grading scale' approach following visual inspection of the canopy features. Spatial-temporal distribution of moisture profiles is co-related with grading scales to comment on the effect of climatic and irrigation scenarios on the degree and intensity of crop disease caused by Phytopthora.

  10. Segmentation of Environmental Time Lapse Image Sequences for the Determination of Shore Lines Captured by Hand-Held Smartphone Cameras

    Science.gov (United States)

    Kröhnert, M.; Meichsner, R.

    2017-09-01

    The relevance of globally environmental issues gains importance since the last years with still rising trends. Especially disastrous floods may cause in serious damage within very short times. Although conventional gauging stations provide reliable information about prevailing water levels, they are highly cost-intensive and thus just sparsely installed. Smartphones with inbuilt cameras, powerful processing units and low-cost positioning systems seem to be very suitable wide-spread measurement devices that could be used for geo-crowdsourcing purposes. Thus, we aim for the development of a versatile mobile water level measurement system to establish a densified hydrological network of water levels with high spatial and temporal resolution. This paper addresses a key issue of the entire system: the detection of running water shore lines in smartphone images. Flowing water never appears equally in close-range images even if the extrinsics remain unchanged. Its non-rigid behavior impedes the use of good practices for image segmentation as a prerequisite for water line detection. Consequently, we use a hand-held time lapse image sequence instead of a single image that provides the time component to determine a spatio-temporal texture image. Using a region growing concept, the texture is analyzed for immutable shore and dynamic water areas. Finally, the prevalent shore line is examined by the resultant shapes. For method validation, various study areas are observed from several distances covering urban and rural flowing waters with different characteristics. Future work provides a transformation of the water line into object space by image-to-geometry intersection.

  11. Gas piston activity of the Nyiragongo lava lake: First insights from a Stereographic Time-Lapse Camera system

    Science.gov (United States)

    Smets, Benoît; d'Oreye, Nicolas; Kervyn, Matthieu; Kervyn, François

    2017-10-01

    Nyiragongo volcano (D.R. Congo), in the western branch of the East African Rift System, is one of the most active volcanoes on Earth. Its eruptive activity is mainly characterized by the presence of a persistent lava lake in its main crater. As observed at other persistent lava lakes, the Nyiragongo lava lake level exhibits metric vertical variations in the form of minutes-to hour-long cycles, which we infer to be gas piston activity. To study this activity, we developed and tested a Stereographic Time-Lapse Camera (STLC) system, which takes stereo-pairs of photographs of the Nyiragongo crater at regular intervals. Each pair of gas- and steam-free images during daytime allows the production of a 3D point cloud. The comparison of the point clouds provides a measurement of topographic changes related to variations in lava lake level. The processing of a first dataset acquired between 18 and 20 September 2011, at an acquisition rate of 1 pair of images every 2 min, revealed cycles of vertical lava lake level variations reaching up to 3.8 m. Lava lake level variations >0.5 m are detected significantly. They are interpreted to result from gas accumulation and release in the lava lake itself. The limitations of the STLC approach are related to the number of cameras used and the atmospheric masking by steam and volcanic gas in the Nyiragongo crater. The proposed photogrammetric approach could be applied elsewhere or in other disciplines, where frequent topographic changes occur.

  12. PFLOTRAN-E4D: A parallel open source PFLOTRAN module for simulating time-lapse electrical resistivity data

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Timothy C.; Hammond, Glenn E.; Chen, Xingyuan

    2017-02-01

    Time-lapse electrical resistivity tomography (ERT) is finding increased application for remotely monitoring processes occurring in the near subsurface in three-dimensions (i.e. 4D monitoring). However, there are few codes capable of simulating the evolution of subsurface resistivity and corresponding tomographic measurements arising from a particular process, particularly in parallel and with an open source license. Herein we describe and demonstrate an electrical resistivity tomography module for the PFLOTRAN subsurface simulation code, named PFLOTRAN-E4D. The PFLOTRAN-E4D module operates in parallel using a dedicated set of compute cores in a master-slave configuration. At each time step, the master processes receives subsurface states from PFLOTRAN, converts those states to bulk electrical conductivity, and instructs the slave processes to simulate a tomographic data set. The resulting multi-physics simulation capability enables accurate feasibility studies for ERT imaging, the identification of the ERT signatures that are unique to a given process, and facilitates the joint inversion of ERT data with hydrogeological data for subsurface characterization. PFLOTRAN-E4D is demonstrated herein using a field study of stage-driven groundwater/river water interaction ERT monitoring along the Columbia River, Washington, USA. Results demonstrate the complex nature of changes subsurface electrical conductivity, in both the saturated and unsaturated zones, arising from water table changes and from river water intrusion into the aquifer. The results also demonstrate the sensitivity of surface based ERT measurements to those changes over time. PFLOTRAN-E4D is available with the PFLOTRAN development version with an open-source license at https://bitbucket.org/pflotran/pflotran-dev .

  13. SEGMENTATION OF ENVIRONMENTAL TIME LAPSE IMAGE SEQUENCES FOR THE DETERMINATION OF SHORE LINES CAPTURED BY HAND-HELD SMARTPHONE CAMERAS

    Directory of Open Access Journals (Sweden)

    M. Kröhnert

    2017-09-01

    Full Text Available The relevance of globally environmental issues gains importance since the last years with still rising trends. Especially disastrous floods may cause in serious damage within very short times. Although conventional gauging stations provide reliable information about prevailing water levels, they are highly cost-intensive and thus just sparsely installed. Smartphones with inbuilt cameras, powerful processing units and low-cost positioning systems seem to be very suitable wide-spread measurement devices that could be used for geo-crowdsourcing purposes. Thus, we aim for the development of a versatile mobile water level measurement system to establish a densified hydrological network of water levels with high spatial and temporal resolution. This paper addresses a key issue of the entire system: the detection of running water shore lines in smartphone images. Flowing water never appears equally in close-range images even if the extrinsics remain unchanged. Its non-rigid behavior impedes the use of good practices for image segmentation as a prerequisite for water line detection. Consequently, we use a hand-held time lapse image sequence instead of a single image that provides the time component to determine a spatio-temporal texture image. Using a region growing concept, the texture is analyzed for immutable shore and dynamic water areas. Finally, the prevalent shore line is examined by the resultant shapes. For method validation, various study areas are observed from several distances covering urban and rural flowing waters with different characteristics. Future work provides a transformation of the water line into object space by image-to-geometry intersection.

  14. ViCAR: An Adaptive and Landmark-Free Registration of Time Lapse Image Data from Microfluidics Experiments

    Directory of Open Access Journals (Sweden)

    Georges Hattab

    2017-05-01

    Full Text Available In order to understand gene function in bacterial life cycles, time lapse bioimaging is applied in combination with different marker protocols in so called microfluidics chambers (i.e., a multi-well plate. In one experiment, a series of T images is recorded for one visual field, with a pixel resolution of 60 nm/px. Any (semi-automatic analysis of the data is hampered by a strong image noise, low contrast and, last but not least, considerable irregular shifts during the acquisition. Image registration corrects such shifts enabling next steps of the analysis (e.g., feature extraction or tracking. Image alignment faces two obstacles in this microscopic context: (a highly dynamic structural changes in the sample (i.e., colony growth and (b an individual data set-specific sample environment which makes the application of landmarks-based alignments almost impossible. We present a computational image registration solution, we refer to as ViCAR: (Visual (Cues based (Adaptive (Registration, for such microfluidics experiments, consisting of (1 the detection of particular polygons (outlined and segmented ones, referred to as visual cues, (2 the adaptive retrieval of three coordinates throughout different sets of frames, and finally (3 an image registration based on the relation of these points correcting both rotation and translation. We tested ViCAR with different data sets and have found that it provides an effective spatial alignment thereby paving the way to extract temporal features pertinent to each resulting bacterial colony. By using ViCAR, we achieved an image registration with 99.9% of image closeness, based on the average rmsd of 4.10−2 pixels, and superior results compared to a state of the art algorithm.

  15. Attention modulates emotional expression processing.

    Science.gov (United States)

    Wronka, Eligiusz; Walentowska, Wioleta

    2011-08-01

    To investigate the time course of emotional expression processing, we recorded ERPs to facial stimuli. The first task was to discriminate emotional expressions. Enhanced negativity of the face-specific N170 was elicited by emotional as opposed to neutral faces, followed by the occipital negativity (240-340 ms poststimulus). The second task was to classify face gender. Here, N170 was unaffected by the emotional expression. However, emotional expression effect was expressed in the anterior positivity (160-250 ms poststimulus) and subsequent occipital negativity (240-340 ms poststimulus). Results support the thesis that structural encoding relevant to gender recognition and simultaneous expression analysis are independent processes. Attention modulates facial emotion processing 140-185 ms poststimulus. Involuntary differentiation of facial expression was observed later (160-340 ms poststimulus), suggesting unintentional attention capture. Copyright © 2011 Society for Psychophysiological Research.

  16. Octave effect in auditory attention.

    Science.gov (United States)

    Borra, Tobias; Versnel, Huib; Kemner, Chantal; van Opstal, A John; van Ee, Raymond

    2013-09-17

    After hearing a tone, the human auditory system becomes more sensitive to similar tones than to other tones. Current auditory models explain this phenomenon by a simple bandpass attention filter. Here, we demonstrate that auditory attention involves multiple pass-bands around octave-related frequencies above and below the cued tone. Intriguingly, this "octave effect" not only occurs for physically presented tones, but even persists for the missing fundamental in complex tones, and for imagined tones. Our results suggest neural interactions combining octave-related frequencies, likely located in nonprimary cortical regions. We speculate that this connectivity scheme evolved from exposure to natural vibrations containing octave-related spectral peaks, e.g., as produced by vocal cords.

  17. Media multitasking, attention, and distraction

    DEFF Research Database (Denmark)

    Aagaard, Jesper

    2015-01-01

    Students often multitask with technologies such as computers, laptops, tablets and smartphones during class. Unfortunately, numerous empirical studies firmly establish a significant drop in academic performance caused by this media multitasking. In this paper it is argued that cognitive studies may...... have clarified the negative consequences of this activity, yet they struggle to address the processes involved in it. A cognitive characterization of attention as a mental phenomenon neglects the interaction between bodies and technologies, and it is suggested that a postphenomenological understanding...

  18. A Real Attention-Getter

    Science.gov (United States)

    2003-01-01

    While most parents would agree that playing videos games is the antithesis of time well spent for their children, recent advances involving NASA biofeedback technology are proving otherwise. The same techniques used to measure brain activity in NASA pilots during flight simulation exercises are now a part of a revolutionary video game system that is helping to improve overall mental awareness for Americans of all ages, including those who suffer from Attention Deficit Hyperactivity Disorder (ADHD).

  19. Emotional attention in acquired prosopagnosia

    Science.gov (United States)

    Lucas, Nadia; Mayer, Eugene; Vuilleumier, Patrik

    2009-01-01

    The present study investigated whether emotionally expressive faces guide attention and modulate fMRI activity in fusiform gyrus in acquired prosopagnosia. Patient PS, a pure case of acquired prosopagnosia with intact right middle fusiform gyrus, performed two behavioral experiments and a functional imaging experiment to address these questions. In a visual search task involving face stimuli, PS was faster to select the target face when it was expressing fear or happiness as compared to when it was emotionally neutral. In a change detection task, PS detected significantly more changes when the changed face was fearful as compared to when it was neutral. Finally, an fMRI experiment showed enhanced activation to emotionally expressive faces and bodies in right fusiform gyrus. In addition, PS showed normal body-selective activation in right fusiform gyrus, partially overlapping the fusiform face area. Together these behavioral and neuroimaging results show that attention was preferentially allocated to emotional faces in patient PS, as observed in healthy subjects. We conclude that systems involved in the emotional guidance of attention by facial expression can function normally in acquired prosopagnosia, and can thus be dissociated from systems involved in face identification. PMID:19401380

  20. Dissociations between developmental dyslexias and attention deficits

    Science.gov (United States)

    Lukov, Limor; Friedmann, Naama; Shalev, Lilach; Khentov-Kraus, Lilach; Shalev, Nir; Lorber, Rakefet; Guggenheim, Revital

    2014-01-01

    We examine whether attention deficits underlie developmental dyslexia, or certain types of dyslexia, by presenting double dissociations between the two. We took into account the existence of distinct types of dyslexia and of attention deficits, and focused on dyslexias that may be thought to have an attentional basis: letter position dyslexia (LPD), in which letters migrate within words, attentional dyslexia (AD), in which letters migrate between words, neglect dyslexia, in which letters on one side of the word are omitted or substituted, and surface dyslexia, in which words are read via the sublexical route. We tested 110 children and adults with developmental dyslexia and/or attention deficits, using extensive batteries of reading and attention. For each participant, the existence of dyslexia and the dyslexia type were tested using reading tests that included stimuli sensitive to the various dyslexia types. Attention deficit and its type was established through attention tasks assessing sustained, selective, orienting, and executive attention functioning. Using this procedure, we identified 55 participants who showed a double dissociation between reading and attention: 28 had dyslexia with normal attention and 27 had attention deficits with normal reading. Importantly, each dyslexia with suspected attentional basis dissociated from attention: we found 21 individuals with LPD, 13 AD, 2 neglect dyslexia, and 12 surface dyslexia without attention deficits. Other dyslexia types (vowel dyslexia, phonological dyslexia, visual dyslexia) also dissociated from attention deficits. Examination of 55 additional individuals with both a specific dyslexia and a certain attention deficit found no attention function that was consistently linked with any dyslexia type. Specifically, LPD and AD dissociated from selective attention, neglect dyslexia dissociated from orienting, and surface dyslexia dissociated from sustained and executive attention. These results indicate that

  1. The pharmacology of visuospatial attention and inhibition

    NARCIS (Netherlands)

    Logemann, H.N.A.

    2013-01-01

    Attention and inhibition are of vital importance in everyday functioning. Problems of attention and inhibition are central to disorders such as Attention Deficit/Hyperactivity Disorder (ADHD). Both bias and disengagement key components of visuospatial attention. Bias refers to neuronal signals that

  2. Does imminent threat capture and hold attention?

    Science.gov (United States)

    Koster, Ernst H W; Crombez, Geert; Van Damme, Stefaan; Verschuere, Bruno; De Houwer, Jan

    2004-09-01

    According to models of attention and emotion, threat captures and holds attention. In behavioral tasks, robust evidence has been found for attentional holding but not for attentional capture by threat. An important explanation for the absence of attentional capture effects is that the visual stimuli used posed no genuine threat. The present study investigated whether visual cues that signal an aversive white noise can elicit attentional capture and holding effects. Cues presented in an attentional task were simultaneously provided with a threat value through an aversive conditioning procedure. Response latencies showed that threatening cues captured and held attention. These results support recent views on attention to threat, proposing that imminent threat captures attention in everyone. (c) 2004 APA, all rights reserved

  3. Dissociations between developmental dyslexias and attention deficits

    Directory of Open Access Journals (Sweden)

    Limor eLukov

    2015-01-01

    Full Text Available We examine whether attention deficits underlie developmental dyslexia, or certain types of dyslexia, by presenting double dissociations between the two. We took into account the existence of distinct types of dyslexia and of attention deficits, and focused on dyslexias that may be thought to have an attentional basis: letter position dyslexia (LPD, in which letters migrate within words, attentional dyslexia (AD, in which letters migrate between words, neglect dyslexia, in which letters on one side of the word are omitted or substituted, and surface dyslexia, in which words are read via the sublexical route.We tested 110 children and adults with developmental dyslexia and/or attention deficits, using extensive batteries of reading and attention.For each participant, the existence of dyslexia and the dyslexia type were tested using reading tests that included stimuli sensitive to the various dyslexia types. Attention deficit and its type was established through attention tasks assessing sustained, selective, orienting, and executive attention functioning. Using this procedure,we identified 55 participants who showed a double dissociation between reading and attention: 28 had dyslexia with normal attention and 27 had attention deficits with normal reading.Each dyslexia with suspected attentional basis dissociated from attention:21 individuals with LPD,13 AD,2 neglect dyslexia,and 12 surface dyslexia. Other dyslexia types(vowel dyslexia, phonological dyslexia, visual dyslexia also dissociated from attention deficits.Examination of 55 additional individuals with both a specific dyslexia and a certain attention deficit found no attention function that was consistently linked with any dyslexia type.Specifically, LPD and AD dissociated from selective attention, neglect dyslexia dissociated from orienting, and surface dyslexia dissociated from sustained and executive attention. These results indicate that visuospatial attention deficits do not underlie

  4. Estimation of soil hydraulic parameters in the field by integrated hydrogeophysical inversion of time-lapse ground-penetrating radar data

    KAUST Repository

    Jadoon, Khan

    2012-01-01

    An integrated hydrogeophysical inversion approach was used to remotely infer the unsaturated soil hydraulic parameters from time-lapse ground-penetrating radar (GPR) data collected at a fixed location over a bare agricultural field. The GPR model combines a full-waveform solution of Maxwell\\'s equations for three-dimensional wave propaga- tion in planar layered media together with global reflection and transmission functions to account for the antenna and its interactions with the medium. The hydrological simu- lator HYDRUS-1D was used with a two layer single- and dual-porosity model. The radar model was coupled to the hydrodynamic model, such that the soil electrical properties (permitivity and conductivity) that serve as input to the GPR model become a function of the hydrodynamic model output (water content), thereby permiting estimation of the soil hydraulic parameters from the GPR data in an inversion loop. To monitor the soil water con- tent dynamics, time-lapse GPR and time domain reflectometry (TDR) measurements were performed, whereby only GPR data was used in the inversion. Significant effects of water dynamics were observed in the time-lapse GPR data and in particular precipitation and evaporation events were clearly visible. The dual porosity model provided betier results compared to the single porosity model for describing the soil water dynamics, which is sup- ported by field observations of macropores. Furthermore, the GPR-derived water content profiles reconstructed from the integrated hydrogeophysical inversion were in good agree- ment with TDR observations. These results suggest that the proposed method is promising for non-invasive characterization of the shallow subsurface hydraulic properties and moni- toring water dynamics at the field scale. © Soil Science Society of America.

  5. Time-lapse changes of P- and S-wave velocities and shear wave splitting in the first year after the 2011 Tohoku earthquake, Japan: shallow subsurface

    Science.gov (United States)

    Sawazaki, Kaoru; Snieder, Roel

    2013-04-01

    We detect time-lapse changes in P- and S-wave velocities (hereafter, VP and VS, respectively) and shear wave splitting parameters associated with the 2011 Tohoku earthquake, Japan, at depths between 0 and 504 m. We estimate not only medium parameters but also the 95 per cent confidence interval of the estimated velocity change by applying a new least squares inversion scheme to the deconvolution analysis of KiK-net vertical array records. Up to 6 per cent VS reduction is observed at more than half of the analysed KiK-net stations in northeastern Japan with over 95 per cent confidence in the first month after the main shock. There is a considerable correlation between the S-wave traveltime delay and the maximum horizontal dynamic strain (MDS) by the main shock motion when the strain exceeds 5 × 10- 4 on the ground surface. This correlation is not clearly observed for MDS at the borehole bottom. On the contrary, VP and shear wave splitting parameters do not show systematic changes after the Tohoku earthquake. These results indicate that the time-lapse change is concentrated near the ground surface, especially in loosely packed soil layers. We conclude that the behaviour of VP, VS and shear wave splitting parameters are explained by the generation of omnidirectional cracks near the ground surface and by the diffusion of water in the porous subsurface. Recovery of VS should be related to healing of the crack which is proportional to the logarithm of the lapse time after the main shock and/or to decompaction after shaking.

  6. Time-lapse microscopy and classification of 2D human mesenchymal stem cells based on cell shape picks up myogenic from osteogenic and adipogenic differentiation.

    Science.gov (United States)

    Seiler, Christof; Gazdhar, Amiq; Reyes, Mauricio; Benneker, Lorin M; Geiser, Thomas; Siebenrock, Klaus A; Gantenbein-Ritter, Benjamin

    2014-09-01

    Current methods to characterize mesenchymal stem cells (MSCs) are limited to CD marker expression, plastic adherence and their ability to differentiate into adipogenic, osteogenic and chondrogenic precursors. It seems evident that stem cells undergoing differentiation should differ in many aspects, such as morphology and possibly also behaviour; however, such a correlation has not yet been exploited for fate prediction of MSCs. Primary human MSCs from bone marrow were expanded and pelleted to form high-density cultures and were then randomly divided into four groups to differentiate into adipogenic, osteogenic chondrogenic and myogenic progenitor cells. The cells were expanded as heterogeneous and tracked with time-lapse microscopy to record cell shape, using phase-contrast microscopy. The cells were segmented using a custom-made image-processing pipeline. Seven morphological features were extracted for each of the segmented cells. Statistical analysis was performed on the seven-dimensional feature vectors, using a tree-like classification method. Differentiation of cells was monitored with key marker genes and histology. Cells in differentiation media were expressing the key genes for each of the three pathways after 21 days, i.e. adipogenic, osteogenic and chondrogenic, which was also confirmed by histological staining. Time-lapse microscopy data were obtained and contained new evidence that two cell shape features, eccentricity and filopodia (= 'fingers') are highly informative to classify myogenic differentiation from all others. However, no robust classifiers could be identified for the other cell differentiation paths. The results suggest that non-invasive automated time-lapse microscopy could potentially be used to predict the stem cell fate of hMSCs for clinical application, based on morphology for earlier time-points. The classification is challenged by cell density, proliferation and possible unknown donor-specific factors, which affect the performance of

  7. Soovimatud lapsed / Jaak Lõhmus

    Index Scriptorium Estoniae

    Lõhmus, Jaak

    2007-01-01

    60-nda Cannes'i filmifestivali filme : Christian Mungiu "Neli kuud, kolm nädalat ja kaks päeva" (Rumeenia) ; Ethan ja Joel Coen'i "Pole maad vanadele meestele" ("No Country for Old Men" ; Ameerika Ühendriigid), Andrei Zvjagintsevi "Pagendus" (Izgnanije" ; muusika Arvo Pärdilt ; Venemaa) ; Kadri Kõusaare "Magnus"

  8. Erivajadustega lapsed / Marika Veisson

    Index Scriptorium Estoniae

    Veisson, Marika, 1949-

    2008-01-01

    Vaimupuudega laste arengu ja kasvatuse iseärasustest, ülevaade ka lastest, kellele on pandud Downi sündroomi ja autismi diagnoos ning tserebraalparalüüsi, tähelepanupuudulikkuse ja hüperaktiivsusega lastest

  9. Time-Lapse Monitoring of an Engineering Scaled Excavation at Federal District, Brazil by Passive Ambient NoiseInterferometry

    Science.gov (United States)

    Cárdenas-Soto, M., Sr.; Hussain, Y.; Martinez-Carvajal, H., Sr.; Martino, S., Sr.; Rocha, M., Sr.

    2016-12-01

    gave Rayleigh wave velocity changes (dv/v=-dt/t). These changes correlated well with initiation and propagation of fracture at the face of this normal slope. It is concluded that cost effective technique, PANI has a good potential for the monitoring of time lapse changes of evolving fractures.

  10. Time lapse imaging of water content with geoelectrical methods: on the interest of working with absolute water content data

    Science.gov (United States)

    Dumont, Gaël; Pilawski, Tamara; Robert, Tanguy; Hermans, Thomas; Garré, Sarah; Nguyen, Frederic

    2016-04-01

    The electrical resistivity tomography is a suitable method to estimate the water content of a waste material and detect changes in water content. Various ERT profiles, both static data and time-lapse, where acquired on a landfill during the Minerve project. In the literature, the relative change of resistivity (Δρ/ρ) is generally computed. For saline or heat tracer tests in the saturated zone, the Δρ/ρ can be easily translated into pore water conductivity or underground temperature changes (provided that the initial salinity or temperature condition is homogeneous over the ERT panel extension). For water content changes in the vadose zone resulting of an infiltration event or injection experiment, many authors also work with the Δρ/ρ or relative changes of water content Δθ/θ (linked to the change of resistivity through one single parameter: the Archie's law exponent "m"). This parameter is not influenced by the underground temperature and pore fluid conductivity (ρ¬w) condition but is influenced by the initial water content distribution. Therefore, you never know if the loss of Δθ/θ signal is representative of the limit of the infiltration front or more humid initial condition. Another approach for the understanding of the infiltration process is the assessment of the absolute change of water content (Δθ). This requires the direct computation of the water content of the waste from the resistivity data. For that purpose, we used petrophysical laws calibrated with laboratory experiments and our knowledge of the in situ temperature and pore fluid conductivity parameters. Then, we investigated water content changes in the waste material after a rainfall event (Δθ= Δθ/θ* θ). This new observation is really representatives of the quantity of water infiltrated in the waste material. However, the uncertainty in the pore fluid conductivity value may influence the computed water changes (Δθ=k*m√(ρw) ; where "m" is the Archie's law exponent

  11. Habitual versus goal-driven attention.

    Science.gov (United States)

    Jiang, Yuhong V

    2017-07-04

    Recent research has expanded the list of factors that control spatial attention. Beside current goals and perceptual salience, statistical learning, reward, motivation and emotion also affect attention. But do these various factors influence spatial attention in the same manner, as suggested by the integrated framework of attention, or do they target different aspects of spatial attention? Here I present evidence that the control of attention may be implemented in two ways. Whereas current goals typically modulate where in space attention is prioritized, search habits affect how one moves attention in space. Using the location probability learning paradigm, I show that a search habit forms when people frequently find a visual search target in one region of space. Attentional cuing by probability learning differs from that by current goals. Probability cuing is implicit and persists long after the probability cue is no longer valid. Whereas explicit goal-driven attention codes space in an environment-centered reference frame, probability cuing is viewer-centered and is insensitive to secondary working memory load and aging. I propose a multi-level framework that separates the source of attentional control from its implementation. Similar to the integrated framework, the multi-level framework considers current goals, perceptual salience, and selection history as major sources of attentional control. However, these factors are implemented in two ways, controlling where spatial attention is allocated and how one shifts attention in space. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. [Early attention to learning disabilities].

    Science.gov (United States)

    Millá, M G

    2006-02-13

    In the early stages of their development, children acquire the skills and knowledge that provide them with the foundations on which they will later add what they learn at school, including skills such as reading, writing and mathematics. The presence of learning difficulties at the infantile stage can affect the development of these academic skills during the period of compulsory schooling. Some children show learning difficulties in their earliest years. Early learning difficulties refer specifically to those problems that occur in the time between birth and the age of six and which reduce the chances of accomplishing the skills and knowledge that are typically acquired during the stage of infancy. There is a correlation between these problems and difficulties linked to cognition, to attention, perception and memory processes, to language skills involving both comprehension and expression, and to visuospatial processing. Their aetiology involves neuropsychological, social and cultural factors, as well as others that derive from the actual learning processes themselves. Following an interdisciplinary model using development scales, psychometric tests and neurodevelopmental monitoring will allow an early diagnosis to be reached. The intervention will be carried out in the medical, social, educational and family areas, and will focus on the aspects that favour maturing, development and the learning of curricular material. The new socio-educational scenario makes it necessary to attend to early learning difficulties in infants' education. Prevention and early attention offer guidelines and strategies to deal with them in a satisfactory manner.

  13. Application of Time-Lapse Seismic Monitoring for the Control and Optimization of CO2 Enhanced Oil Recovery Operations

    Energy Technology Data Exchange (ETDEWEB)

    Brian Toelle

    2008-11-30

    This project, 'Application of Time-Lapse Seismic Monitoring for the Control and Optimization of CO{sub 2} Enhanced Oil Recovery Operations', investigated the potential for monitoring CO{sub 2} floods in carbonate reservoirs through the use of standard p-wave seismic data. This primarily involved the use of 4D seismic (time lapse seismic) in an attempt to observe and map the movement of the injected CO{sub 2} through a carbonate reservoir. The differences between certain seismic attributes, such as amplitude, were used for this purpose. This technique has recently been shown to be effective in CO{sub 2} monitoring in Enhanced Oil Recovery (EOR) projects, such as Weyborne. This study was conducted in the Charlton 30/31 field in the northern Michigan Basin, which is a Silurian pinnacle reef that completed its primary production in 1997 and was scheduled for enhanced oil recovery using injected CO{sub 2}. Prior to injection an initial 'Base' 3D survey was obtained over the field and was then processed and interpreted. CO{sub 2} injection within the main portion of the reef was conducted intermittently during 13 months starting in August 2005. During this time, 29,000 tons of CO{sub 2} was injected into the Guelph formation, historically known as the Niagaran Brown formation. By September 2006, the reservoir pressure within the reef had risen to approximately 2000 lbs and oil and water production from the one producing well within the field had increased significantly. The determination of the reservoir's porosity distribution, a critical aspect of reservoir characterization and simulation, proved to be a significant portion of this project. In order to relate the differences observed between the seismic attributes seen on the multiple 3D seismic surveys and the actual location of the CO{sub 2}, a predictive reservoir simulation model was developed based on seismic attributes obtained from the base 3D seismic survey and available well data. This

  14. Attention theory and training research

    Science.gov (United States)

    Connelly, James G., Jr.; Wickens, Christopher D.; Lintern, Gavan; Harwood, Kelly

    1987-01-01

    This study used elements of attention theory as a methodological basis to decompose a complex training task in order to improve training efficiency. The complex task was a microcomputer flight simulation where subjects were required to control the stability of their own helicopter while acquiring and engaging enemy helicopers in a threat enviroment. Subjects were divided into whole-task, part-task, and part/open loop adaptive task groups in a transfer of training paradigm. The effect of reducing mental workload at the early stages of learning was examined with respect to the degree that subordinate elements of the complex task could be automated through practice of consistent, learnable stimulus-response relationships. Results revealed trends suggesting the benefit of isolating consistently mapped sub-tasks for part-task training and the presence of a time-sharing skill over and above the skill required for the separate subtasks.

  15. Attention-Deficit/Hyperactivity Disorder.

    Science.gov (United States)

    Bokor, Gyula; Anderson, Peter D

    2014-08-01

    Attention-deficit/hyperactivity disorder (ADHD) is a neurobiological condition of childhood onset with the hallmarks of inattention, impulsivity, and hyperactivity. Inattention includes excessive daydreaming, disorganization, and being easily distracted. Impulsivity manifests as taking an action before fully thinking of the consequences. Hyperactivity includes an excessive rate of speech and motor activity. Complications of ADHD include academic failure, low self-esteem, poor work performance, substance abuse, criminal justice issues, and social problems. ADHD is predominately due to decreased activity in the frontal lobe. Dopamine and norepinephrine are the main neurotransmitters involved in the pathophysiology of ADHD. Pharmacological treatment of ADHD includes psychostimulants, norepinephrine reuptake inhibitors, α2 agonists, bupropion, and monoamine oxidase inhibitors. The most effective medications are the psychostimulants. Nonpharmacological treatment of ADHD includes coaching, providing structure, academic accommodations, and work accommodations. © The Author(s) 2014.

  16. Perception of ensemble statistics requires attention.

    Science.gov (United States)

    Jackson-Nielsen, Molly; Cohen, Michael A; Pitts, Michael A

    2017-02-01

    To overcome inherent limitations in perceptual bandwidth, many aspects of the visual world are represented as summary statistics (e.g., average size, orientation, or density of objects). Here, we investigated the relationship between summary (ensemble) statistics and visual attention. Recently, it was claimed that one ensemble statistic in particular, color diversity, can be perceived without focal attention. However, a broader debate exists over the attentional requirements of conscious perception, and it is possible that some form of attention is necessary for ensemble perception. To test this idea, we employed a modified inattentional blindness paradigm and found that multiple types of summary statistics (color and size) often go unnoticed without attention. In addition, we found attentional costs in dual-task situations, further implicating a role for attention in statistical perception. Overall, we conclude that while visual ensembles may be processed efficiently, some amount of attention is necessary for conscious perception of ensemble statistics. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. On the evolution of conscious attention.

    Science.gov (United States)

    Haladjian, Harry Haroutioun; Montemayor, Carlos

    2015-06-01

    This paper aims to clarify the relationship between consciousness and attention through theoretical considerations about evolution. Specifically, we will argue that the empirical findings on attention and the basic considerations concerning the evolution of the different forms of attention demonstrate that consciousness and attention must be dissociated regardless of which definition of these terms one uses. To the best of our knowledge, no extant view on the relationship between consciousness and attention has this advantage. Because of this characteristic, this paper presents a principled and neutral way to settle debates concerning the relationship between consciousness and attention, without falling into disputes about the meaning of these terms. A decisive conclusion of this approach is that extreme views on the relationship between consciousness and attention must be rejected, including identity and full dissociation views. There is an overlap between the two within conscious attention, but developing a full understanding of this mechanism requires further empirical investigations.

  18. Attentional capture by working memory contents.

    Science.gov (United States)

    Pan, Yi

    2010-06-01

    There has been controversy on whether working memory (WM) contents automatically guide attention. The present study tried to replicate the effect of WM-based attentional capture using an adaption of Downing's (2000) paradigm, in which WM and attentional capture were combined. Subjects were presented with an attention display containing two objects, one of which could be precued by a matching item being held in WM. As measured by a probe discrimination task, the memory-matching object had a privileged status to capture attention regardless of the stimulus onset asynchronies between the memory cue and the attention display, even when there was absolutely no benefit for subjects to bias attention in favour of the memory match. These results suggest that WM contents guide attention in an involuntary manner. The implications of current findings for understanding of WM effects on visual selection are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  19. A Reevaluation of the Attentional Inertia Concept

    NARCIS (Netherlands)

    W.J.M.I. Verbeke (Willem)

    1992-01-01

    textabstractAnderson's (1983) theory about children's attention behavior during television viewing hypothesizes that attention behavior is affected by positive feedback (the inertia hypothesis) and the degree to which a child understands the television program. During an experiment, neither

  20. ATTENTIONAL NETWORKS AND SELECTIVE VISUAL SYSTEM

    National Research Council Canada - National Science Library

    ALEJANDRO CASTILLO MORENO; ANGÉLICA PATERNINA MARÍN

    2006-01-01

    ... system.From this last point of view, we will emphasize on the attentional networks theory of Posner, thatproposes different systems to explain diverse aspects of attention, but they are related to each...

  1. Study of time-lapse processing for dynamic hydrologic conditions. [electronic satellite image analysis console for Earth Resources Technology Satellites imagery

    Science.gov (United States)

    Serebreny, S. M.; Evans, W. E.; Wiegman, E. J.

    1974-01-01

    The usefulness of dynamic display techniques in exploiting the repetitive nature of ERTS imagery was investigated. A specially designed Electronic Satellite Image Analysis Console (ESIAC) was developed and employed to process data for seven ERTS principal investigators studying dynamic hydrological conditions for diverse applications. These applications include measurement of snowfield extent and sediment plumes from estuary discharge, Playa Lake inventory, and monitoring of phreatophyte and other vegetation changes. The ESIAC provides facilities for storing registered image sequences in a magnetic video disc memory for subsequent recall, enhancement, and animated display in monochrome or color. The most unique feature of the system is the capability to time lapse the imagery and analytic displays of the imagery. Data products included quantitative measurements of distances and areas, binary thematic maps based on monospectral or multispectral decisions, radiance profiles, and movie loops. Applications of animation for uses other than creating time-lapse sequences are identified. Input to the ESIAC can be either digital or via photographic transparencies.

  2. Human and Climate Amplified Rapid River Bluff Erosion: an Application of Terrestrial-Based Structure-from-Motion and Time-Lapse Photogrammetry in the Midwestern USA

    Science.gov (United States)

    Kelly, S. A.; Belmont, P.

    2016-12-01

    The Minnesota River Basin (MRB), south central Minnesota, is an extraordinary natural laboratory, and is currently impaired for excess sediments and nutrients. Tributaries of the Minnesota River have been actively incising and meandering into glacial tills for the last 13,400 years in response to a catastrophic base level drop. It is this geologic history combined with modern agricultural intensification and hydrologic change that provide a unique opportunity to study remarkably rapid bluff erosion using photogrammetry. Here we seek to understand the dominant mechanisms (fluvial toe erosion, freeze-thaw, groundwater sapping, tree throw, positive pore water pressures) and magnitude of bluff erosion using daily time-lapse photographs, repeat photo surveys, Structure-from-Motion (SfM), and calculations of bluff volumetric change through time. We expect for increased precipitation and streamflows in the basin to have accelerated bluff erosion via channel widening and migration. In general, we find that bluff failures occur during or immediately following (1-2 days) heavy rainfall events, especially during spring thaw, and the removal, or transport of the failed material out of the reach coincides with hydrograph flood peaks. Through the combined use of time-lapse and SfM photogrammetry we are able to identify the precipitation and flow events which occur with a frequency and magnitude large enough to effectively dominate bluff erosion. Identifying this `effective discharge' of bluff erosion is regionally important for sediment reduction strategies in the MRB.

  3. Heterogeneous cell-cycle behavior in response to UVB irradiation by a population of single cancer cells visualized by time-lapse FUCCI imaging.

    Science.gov (United States)

    Miwa, Shinji; Yano, Shuya; Kimura, Hiroaki; Yamamoto, Mako; Toneri, Makoto; Murakami, Takashi; Hayashi, Katsuhiro; Yamamoto, Norio; Fujiwara, Toshiyoshi; Tsuchiya, Hiroyuki; Hoffman, Robert M

    2015-01-01

    The present study analyzed the heterogeneous cell-cycle dependence and fate of single cancer cells in a population treated with UVB using a fluorescence ubiquitination-based cell-cycle (FUCCI) imaging system. HeLa cells expressing FUCCI were irradiated by 100 or 200 J/m(2) UVB. Modulation of the cell-cycle and apoptosis were observed by time-lapse confocal microscopy imaging every 30 min for 72 h. Correlation between cell survival and factors including cell-cycle phase at the time of the irradiation of UVB, mitosis and the G1/S transition were analyzed using the Kaplan-Meier method along with the log rank test. Time-lapse FUCCI imaging of HeLa cells demonstrated that UVB irradiation induced cell-cycle arrest in S/G2/M phase in the majority of the cells. The cells irradiated by 100 or 200 J/m(2) UVB during G0/G1 phase had a higher survival rate than the cells irradiated during S/G2/M phase. A minority of cells could escape S/G2/M arrest and undergo mitosis which significantly correlated with decreased survival of the cells. In contrast, G1/S transition significantly correlated with increased survival of the cells after UVB irradiation. UVB at 200 J/m(2) resulted in a greater number of apoptotic cells.

  4. Incubator-independent cell-culture perfusion platform for continuous long-term microelectrode array electrophysiology and time-lapse imaging.

    Science.gov (United States)

    Saalfrank, Dirk; Konduri, Anil Krishna; Latifi, Shahrzad; Habibey, Rouhollah; Golabchi, Asiyeh; Martiniuc, Aurel Vasile; Knoll, Alois; Ingebrandt, Sven; Blau, Axel

    2015-06-01

    Most in vitro electrophysiology studies extract information and draw conclusions from representative, temporally limited snapshot experiments. This approach bears the risk of missing decisive moments that may make a difference in our understanding of physiological events. This feasibility study presents a simple benchtop cell-culture perfusion system adapted to commercial microelectrode arrays (MEAs), multichannel electrophysiology equipment and common inverted microscopy stages for simultaneous and uninterrupted extracellular electrophysiology and time-lapse imaging at ambient CO2 levels. The concept relies on a transparent, replica-casted polydimethylsiloxane perfusion cap, gravity- or syringe-pump-driven perfusion and preconditioning of pH-buffered serum-free cell-culture medium to ambient CO2 levels at physiological temperatures. The low-cost microfluidic in vitro enabling platform, which allows us to image cultures immediately after cell plating, is easy to reproduce and is adaptable to the geometries of different cell-culture containers. It permits the continuous and simultaneous multimodal long-term acquisition or manipulation of optical and electrophysiological parameter sets, thereby considerably widening the range of experimental possibilities. Two exemplary proof-of-concept long-term MEA studies on hippocampal networks illustrate system performance. Continuous extracellular recordings over a period of up to 70 days revealed details on both sudden and gradual neural activity changes in maturing cell ensembles with large intra-day fluctuations. Correlated time-lapse imaging unveiled rather static macroscopic network architectures with previously unreported local morphological oscillations on the timescale of minutes.

  5. Deriving Macropore and Preferential Flow Parameters from Tracer and Time-lapse 3D GPR Experiments at the Plot-Scale

    Science.gov (United States)

    Jackisch, Conrad; Allroggen, Niklas; Tronicke, Jens; Zehe, Erwin

    2014-05-01

    "Hydrology - a science in which all processes are preferential" (Uhlenbrook, 2006) - as such preferential flow is known and discussed in hydrology since almost three decades. At the same time, preferential flow remains problematic as explicit descriptions are hard to define and upscale and implicit descriptions remain rather case sensitive. Moreover, our techniques to monitor preferential flow and especially flow structures are very limited. We conducted three multi-tracer plot-scale (1m x 1m) sprinkler experiments at a forested hillslope in the Attert Basin in Luxembourg with prevailing geogenic and biogenic preferential flow structures. It was accompanied by a 3D time-lapse GPR (Ground Penetrating Radar) survey covering an area of 3m x 3m. We present the results with special emphasis on the derivation of macropore parameters for further modelling. To do so, we developed an automated analysis of images from excavated Brilliant Blue stained profiles. Additionally, we analyse our time-lapse GPR data with respect to temporal changes and derive 3D strutural information of the preferential flow patterns. Superior to tracers, this high resolution subsurface imaging technique is non-invasive, repeatable and therefore helps to disentangle the dye stained patterns towards process observation. The results of the image analyses and the GPR surveys are compared and referenced to soil moisture monitoring, sampled Bromide profiles and stable isotope signatures. We further discuss implications for joint development of model concepts and observation methods.

  6. The type of GnRH analogue used during controlled ovarian stimulation influences early embryo developmental kinetics: a time-lapse study.

    Science.gov (United States)

    Muñoz, Manuel; Cruz, María; Humaidan, Peter; Garrido, Nicolás; Pérez-Cano, Inmaculada; Meseguer, Marcos

    2013-06-01

    To explore if the GnRH analogue used for controlled ovarian stimulation (COS) and the ovulation triggering factor (GnRH agonist + hCG triggering versus GnRH antagonist + GnRH agonist triggering) affect embryo development and kinetics. In a retrospective cohort study in the Instituto Valenciano de Infertilidad (IVI) Alicante and the Instituto Universitario-IVI Valencia, Spain, 2817 embryos deriving from 400 couples undergoing oocyte donation were analysed. After controlled ovarian stimulation and IVF/intracytoplamic sperm injection, the timing of embryonic cleavages was assessed by a video time-lapse system. The results were analysed using Student's t test for comparison of timings (hours) and Chi-squared test for comparison of proportions. A p-value < 0.05 was considered to be statistically significant. Embryos from cycles co-treated with GnRH antagonist + GnRH agonist (n = 2101) cleaved faster than embryos deriving from patients co-treated with GnRH agonist + hCG (n = 716): these differences were significant at the first stages of development but they disappeared as long as the embryo developed. Assessing embryo quality in terms of morphokinetic characteristics, we did not find significant differences between the two groups. By adopting a time-lapse video system, we can suggest that the type of protocol used for controlled ovarian stimulation influences embryo kinetics of development but these variations are not reflected in embryo quality. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. Attention as foraging for information and value

    OpenAIRE

    Manohar, Sanjay G.; Husain, Masud

    2013-01-01

    What is the purpose of attention? One avenue of research has led to the proposal that attention might be crucial for gathering information about the environment, while other lines of study have demonstrated how attention may play a role in guiding behavior to rewarded options. Many experiments that study attention require participants to make a decision based on information acquired discretely at one point in time. In real-world situations, however, we are usually not presented with informati...

  8. Attention as foraging for information and reward

    OpenAIRE

    Manohar, Sanjay G.; Masud eHusain

    2013-01-01

    What is the purpose of attention? One avenue of research has led to the proposal that attention might be crucial for gathering information about the environment, while other lines of study have demonstrated attention's role in guiding behavior to rewarded options. Many experiments to study attention require participants to make a decision based on information acquired discretely at one point in time. In real-world situations, however, we are usually not presented with information about wh...

  9. Effects of presession attention on the frequency of attention-maintained behavior.

    OpenAIRE

    O'Reilly, M F

    1999-01-01

    The effect of prior attention was systematically manipulated to study its influence on rates of yelling and head hitting, both maintained by positive reinforcement in the form of attention. Higher levels of head hitting occurred in analogue attention conditions when the person was deprived of attention (no social interactions for 1 hr) prior to the analysis in comparison to when the person received high levels of attention (attention delivered on a fixed-time 30-s schedule for 1 hr) prior to ...

  10. attention deficit hyperactivity disorder intervention: strategies

    African Journals Online (AJOL)

    Elizabeth

    Abstract. This paper addresses attention deficit hyperactivity disorder intervention strategies for primary school teachers. Wrong labelling of children with attention deficit hyperactivity disorder has given rise to this paper. Hitherto not much attention has been given to the pupils who manifest symptoms of this chronic.

  11. The Attentional Blink in Developing Readers

    Science.gov (United States)

    McLean, Gregor M. T.; Stuart, Geoffrey W.; Visser, Troy A. W.; Castles, Anne

    2009-01-01

    The attentional blink refers to a reduction in accuracy that occurs when identifying the second of two targets presented within approximately 500 msec of each other. This research explored individual differences in the attentional blink in a sample of 86 children (aged 8-10) with normally developing reading skills. The attentional blink was…

  12. Everyday Attention Failures: An Individual Differences Investigation

    Science.gov (United States)

    Unsworth, Nash; McMillan, Brittany D.; Brewer, Gene A.; Spillers, Gregory J.

    2012-01-01

    The present study examined individual differences in everyday attention failures. Undergraduate students completed various cognitive ability measures in the laboratory and recorded everyday attention failures in a diary over the course of a week. The majority of attention failures were failures of distraction or mind wandering in educational…

  13. Attention dysfunction subtypes of developmental dyslexia.

    Science.gov (United States)

    Lewandowska, Monika; Milner, Rafał; Ganc, Małgorzata; Włodarczyk, Elżbieta; Skarżyński, Henryk

    2014-11-12

    Previous studies indicate that many different aspects of attention are impaired in children diagnosed with developmental dyslexia (DD). The objective of the present study was to identify cognitive profiles of DD on the basis of attentional test performance. 78 children with DD (30 girls, 48 boys, mean age of 12 years ±8 months) and 32 age- and sex-matched non-dyslexic children (14 girls, 18 boys) were examined using a battery of standardized tests of reading, phonological and attentional processes (alertness, covert shift of attention, divided attention, inhibition, flexibility, vigilance, and visual search). Cluster analysis was used to identify subtypes of DD. Dyslexic children showed deficits in alertness, covert shift of attention, divided attention, flexibility, and visual search. Three different subtypes of DD were identified, each characterized by poorer performance on the reading, phonological awareness, and visual search tasks. Additionally, children in cluster no. 1 displayed deficits in flexibility and divided attention. In contrast to non-dyslexic children, cluster no. 2 performed poorer in tasks involving alertness, covert shift of attention, divided attention, and vigilance. Cluster no. 3 showed impaired covert shift of attention. These results indicate different patterns of attentional impairments in dyslexic children. Remediation programs should address the individual child's deficit profile.

  14. Attentional bias predicts heroin relapse following treatment

    NARCIS (Netherlands)

    Marissen, Marlies A. E.; Franken, Ingmar H. A.; Waters, Andrew J.; Blanken, Peter; van den Brink, Wim; Hendriks, Vincent M.

    2006-01-01

    AIMS: Previous studies have shown that abstinent heroin addicts exhibit an attentional bias to heroin-related stimuli. It has been suggested that attentional bias may represent a vulnerability to relapse into drug use. In the present study, the predictive value of pre-treatment attentional bias on

  15. Role of attentional tags in working memory-driven attentional capture.

    Science.gov (United States)

    Kuo, Chun-Yu; Chao, Hsuan-Fu

    2014-08-01

    Recent studies have demonstrated that the contents of working memory capture attention when performing a visual search task. However, it remains an intriguing and unresolved question whether all kinds of items stored in working memory capture attention. The present study investigated this issue by manipulating the attentional tags (target or distractor) associated with information maintained in working memory. The results showed that working memory-driven attentional capture is a flexible process, and that attentional tags associated with items stored in working memory do modulate attentional capture. When items were tagged as a target, they automatically captured attention; however, when items were tagged as a distractor, attentional capture was reduced.

  16. Resting cardiac vagal tone predicts intraindividual reaction time variability during an attention task in a sample of young and healthy adults.

    Science.gov (United States)

    Williams, DeWayne P; Thayer, Julian F; Koenig, Julian

    2016-12-01

    Intraindividual reaction time variability (IIV), defined as the variability in trial-to-trial response times, is thought to serve as an index of central nervous system function. As such, greater IIV reflects both poorer executive brain function and cognitive control, in addition to lapses in attention. Resting-state vagally mediated heart rate variability (vmHRV), a psychophysiological index of self-regulatory abilities, has been linked with executive brain function and cognitive control such that those with greater resting-state vmHRV often perform better on cognitive tasks. However, research has yet to investigate the direct relationship between resting vmHRV and task IIV. The present study sought to examine this relationship in a sample of 104 young and healthy participants who first completed a 5-min resting-baseline period during which resting-state vmHRV was assessed. Participants then completed an attentional (target detection) task, where reaction time, accuracy, and trial-to-trial IIV were obtained. Results showed resting vmHRV to be significantly related to IIV, such that lower resting vmHRV predicted higher IIV on the task, even when controlling for several covariates (including mean reaction time and accuracy). Overall, our results provide further evidence for the link between resting vmHRV and cognitive control, and extend these notions to the domain of lapses in attention, as indexed by IIV. Implications and recommendations for future research on resting vmHRV and cognition are discussed. © 2016 Society for Psychophysiological Research.

  17. Prefrontal control of attention to threat

    Directory of Open Access Journals (Sweden)

    Polly V Peers

    2013-02-01

    Full Text Available Attentional control refers to the regulatory processes that ensure that our actions are in accordance with our goals. Dual-system accounts view temperament as consisting of both individual variation in emotionality (e.g. trait anxiety and variation in regulatory attentional mechanisms that act to modulate emotionality. Increasing evidence links trait variation in attentional control to clinical mood and anxiety disorder symptoms, independent of trait emotionality. Attentional biases to threat have been robustly linked to mood and anxiety disorders. However, the role of variation in attentional control in influencing such biases, and the neural underpinnings of trait variation in attentional control, are unknown. Here, we show, that individual differences in trait attentional control, even when accounting for trait and state anxiety, are related to the magnitude of an attentional blink following threat-related targets. Moreover, we demonstrate that activity in dorsolateral prefrontal cortex, is observed specifically in relation to control of attention over threatening stimuli, in line with neural theories of attentional control, such as guided activation theory. These results have key implications for neurocognitive theories of attentional bias and emotional resilience.

  18. Consciousness and Attention: On sufficiency and necessity

    Directory of Open Access Journals (Sweden)

    Jeroen J A Van Boxtel

    2010-12-01

    Full Text Available Recent research has slowly corroded a belief that selective attention and consciousness are so tightly entangled that they cannot be individually examined. In this review, we summarize psychophysical and neurophysiological evidence for a dissociation between top-down attention and consciousness. The evidence includes recent findings that show subjects can attend to perceptually invisible objects. More contentious is the finding that subjects can become conscious of an isolated object, or the gist of the scene in the near absence of top-down attention; we critically re-examine the possibility of ‘complete’ absence of top-down attention. We also cover the recent flurry of studies that utilized independent manipulation of attention and consciousness. These studies have shown paradoxical effects of attention, including examples where top-down attention and consciousness have opposing effects, leading us to strengthen and revise our previous views. Neuroimaging studies with EEG, MEG and fMRI are uncovering the distinct neuronal correlates of selective attention and consciousness in dissociative paradigms. These findings point to a functional dissociation: attention as analyzer and consciousness as synthesizer. Separating the effects of selective visual attention from those of visual consciousness is of paramount importance to untangle the neural substrates of consciousness from those for attention.

  19. Association between the attention deficits and delinquency

    Directory of Open Access Journals (Sweden)

    Robert Opora

    2011-12-01

    Full Text Available In the society we can find a lot of prejudices concerning AD/HD. The article contains facts and evidence based on research presenting that the delinquency is very often a distant complication of attention deficits but it doesn’t mean that a child with attention deficits has to be delinquent. The article describes the association between the attention deficits and delinquency. There are presented some risk factors coming from the attention deficits and protective factors which let the child follow the social norms. The research was based on 108 delinquent juveniles staying under the probation supervision. The purpose of the research was to evaluate the frequency of the attention deficits among delinquent juveniles staying under supervision. The research findings concern also the association between the attention deficit and external behavioural disorders. In the summary several conditions are described which are important to protect children with attention deficit from delinquency.

  20. ATTENTIONAL NETWORKS AND SELECTIVE VISUAL SYSTEM

    Directory of Open Access Journals (Sweden)

    ALEJANDRO CASTILLO MORENO

    2006-05-01

    Full Text Available In this paper we checked the principal researches and theories to explain the attention system functioning.We are going to start reviewing along time about the concept of attention, from filter theories andresources distributor theories, to the current theories in which attention is conceived as a control system.From this last point of view, we will emphasize on the attentional networks theory of Posner, thatproposes different systems to explain diverse aspects of attention, but they are related to each other. Atlast in this paper, we will mention experimental results that have been important to characterize theselective attentional mechanisms of the human visual system, using the attentional spotlight model forthis aim.

  1. Does interest broaden or narrow attentional scope?

    Science.gov (United States)

    Sung, Billy; Yih, Jennifer

    2015-08-10

    Theory proposes that interest is a positive emotion that may either broaden attention to facilitate processing of new information, or narrow attention to preserve engagement with new information. To our knowledge, no research has directly examined the effect of interest on attentional scope. Across four experiments, we show that traits associated with the propensity to experience interest-specifically, trait curiosity and internal boredom proneness-are associated with a narrower scope of attention. We also find that, instead of broadening, interest actually narrows attentional scope in comparison to a neutral state and awe. Challenging the conventional notion that all positive emotions broaden cognition and attention, our findings suggest that specific emotions influence attention in ways that extend beyond a general emotional valence effect.

  2. Task Engagement and Attentional Resources.

    Science.gov (United States)

    Matthews, Gerald; Warm, Joel S; Smith, Andrew P

    2017-02-01

    Two studies tested multivariate models of relationships between subjective task engagement and vigilance. The second study included a stress factor (cold infection). Modeling tested relationships between latent factors for task engagement and vigilance, and the role of engagement in mediating effects of cold infection. Raja Parasuraman's research on vigilance identified several key issues, including the roles of task factors, arousal processes, and individual differences, within the framework of resource theory. Task engagement is positively correlated with performance on various attentional tasks and may serve as a marker for resource availability. In the first study, 229 participants performed simultaneous and successive vigilance tasks. In the second study, 204 participants performed a vigilance task and a variable-foreperiod simple reaction-time task on two separate days. On the second day, 96 participants performed while infected with a naturally occurring common cold. Task engagement was assessed in both studies. In both studies, vigilance decrement in hit rate was observed, and task performance led to loss of task engagement. Cold infection also depressed both vigilance and engagement. Fitting structural equation models indicated that simultaneous and successive tasks should be represented by separate latent factors (Study 1), and task engagement fully mediated the impact of cold infection on vigilance but not reaction time (Study 2). Modeling individual differences in task engagement elucidates the role of resources in vigilance and underscores the relevance of Parasuraman's vision of the field. Assessment of task engagement may support diagnostic monitoring of operators performing tasks requiring vigilance.

  3. Attentional tradeoffs in the pigeon.

    Science.gov (United States)

    Vyazovska, O V; Teng, Y; Wasserman, E A

    2014-05-01

    We deployed the Multiple Necessary Cues (MNC) discrimination task to see if pigeons can simultaneously attend to four different dimensions of complex visual stimuli. Specifically, we trained nine pigeons (Columba livia) on a go/no go discrimination to peck only 1 of 16 compound stimuli created from all possible combinations of two stimulus values from four separable visual dimensions: shape (circle/square), size (large/small), line orientation (horizontal/vertical), and brightness (dark/light). Some of the pigeons had CLHD (circle, large, horizontal, dark) as the positive stimulus (S+), whereas others had SSVL (square, small, vertical, light) as the S+. We recorded touchscreen pecking during the first 15 s that each stimulus was presented on each training trial. Discrimination training continued until pigeons' rates of responding to all 15 negative stimuli (S-s) fell to less than 15% of their response rates to the S+. All pigeons acquired the MNC discrimination, suggesting that they attended to all four dimensions of the multidimensional stimuli. Learning rate was similar for all four dimensions, indicating equivalent salience of the discriminative stimuli. The more dimensions along which the S-s differed from the S+, the faster was discrimination learning, suggesting an added benefit from increasing perceptual disparities of the S-s from the S+. Finally, evidence of attentional tradeoffs among the four dimensions was seen during discrimination learning, raising interesting questions concerning the possible control of behavior by elemental and configural stimuli. © Society for the Experimental Analysis of Behavior.

  4. Modality-specificity of selective attention networks

    Directory of Open Access Journals (Sweden)

    Hannah Jamieson Stewart

    2015-11-01

    Full Text Available Objective: To establish the modality specificity and generality of selective attention networks. Method: Forty-eight young adults completed a battery of four auditory and visual selective attention tests based upon the Attention Network framework: the visual and auditory Attention Network Tests (vANT, aANT, the Test of Everyday Attention (TEA, and the Test of Attention in Listening (TAiL. These provided independent measures for auditory and visual alerting, orienting, and conflict resolution networks. The measures were subjected to an exploratory factor analysis to assess underlying attention constructs. Results: The analysis yielded a four-component solution. The first component comprised of a range of measures from the TEA and was labeled ‘general attention’. The third component was labeled ‘auditory attention’, as it only contained measures from the TAiL using pitch as the attended stimulus feature. The second and fourth components were labeled as ‘spatial orienting’ and ‘spatial conflict’, respectively – they were comprised of orienting and conflict resolution measures from the vANT, aANT and TAiL attend-location task – all tasks based upon spatial judgments (e.g., the direction of a target arrow or sound location. Conclusions: These results do not support our a-priori hypothesis that attention networks are either modality specific or supramodal. Auditory attention separated into selectively attending to spatial and non-spatial features, with the auditory spatial attention loading onto the same factor as visual spatial attention, suggesting spatial attention is supramodal. However, since our study did not include a non-spatial measure of visual attention, further research will be required to ascertain whether non-spatial attention is modality-specific.

  5. Acute sleep deprivation and circadian misalignment associated with transition onto the first night of work impairs visual selective attention.

    Directory of Open Access Journals (Sweden)

    Nayantara Santhi

    2007-11-01

    Full Text Available Overnight operations pose a challenge because our circadian biology promotes sleepiness and dissipates wakefulness at night. Since the circadian effect on cognitive functions magnifies with increasing sleep pressure, cognitive deficits associated with night work are likely to be most acute with extended wakefulness, such as during the transition from a day shift to night shift.To test this hypothesis we measured selective attention (with visual search, vigilance (with Psychomotor Vigilance Task [PVT] and alertness (with a visual analog scale in a shift work simulation protocol, which included four day shifts followed by three night shifts. There was a nocturnal decline in cognitive processes, some of which were most pronounced on the first night shift. The nighttime decrease in visual search sensitivity was most pronounced on the first night compared with subsequent nights (p = .04, and this was accompanied by a trend towards selective attention becoming 'fast and sloppy'. The nighttime increase in attentional lapses on the PVT was significantly greater on the first night compared to subsequent nights (p<.05 indicating an impaired ability to sustain focus. The nighttime decrease in subjective alertness was also greatest on the first night compared with subsequent nights (p<.05.These nocturnal deficits in attention and alertness offer some insight into why occupational errors, accidents, and injuries are pronounced during night work compared to day work. Examination of the nighttime vulnerabilities underlying the deployment of attention can be informative for the design of optimal work schedules and the implementation of effective countermeasures for performance deficits during night work.

  6. Time-Lapse Acoustic, Transport, and NMR Measurements to Monitor Induced Microstructural Changes of Carbonate Rocks During Injection of CO2-Rich Water

    Science.gov (United States)

    Grombacher, D.; Vanorio, T.; Ebert, Y.

    2011-12-01

    Geophysical monitoring during CO2 injection is necessary to ensure that 1) injected CO2 fills the reservoir as predicted, and that 2) injected CO2 does not migrate towards regions where it may escape. Injection of CO2 results in an altered equilibrium between the pore fluid and the host rock causing chemo-mechanical processes to occur which may impact rock frame properties. In order to improve monitoring techniques, further characterization of injection-induced microstructural changes due to chemo-mechanical processes is needed. We attempt to answer the following questions: How does injection alter the pore network, and how do injection-induced microstructural changes impact seismic properties? An experiment consisting of a suite of six concurrent and independent time-lapse measurements including permeability, porosity, acoustic, nuclear magnetic resonance (NMR) T2 relaxation, and scanning electron microscopy (SEM) and CT-scan images were conducted on two types of carbonate rocks (micritic limestones, and chalky, micritic carbonates). Measurements were taken as a function of the total injected volume of CO2-rich water (which mimics CO2 injection). Injections took place both under bench top conditions and under conditions of constant confining and pore pressures of 15MPa and 12MPa, respectively. Each measurement type is independent and sensitive to different pore properties, allowing us to determine how the microstructure is altered by considering the data from all measurement types simultaneously. Additionally, time-lapse measurements allow us to quantify induced pore structure changes. With increased injection of CO2-rich water, micritic limestones exhibit increased sensitivity of velocity to confining pressure, large permeability increases (~200%), and much variation in their T2 distribution. We hypothesize that injection alters the pore network by increasing pore connectivity and promoting the formation of more elongated pores. In contrast, chalkly, micritic

  7. Reduced memory and attention performance in a population-based sample of young adults with a moderate lifetime use of cannabis, ecstasy and alcohol.

    Science.gov (United States)

    Indlekofer, F; Piechatzek, M; Daamen, M; Glasmacher, C; Lieb, R; Pfister, H; Tucha, O; Lange, K W; Wittchen, H U; Schütz, C G

    2009-07-01

    Regular use of illegal drugs is suspected to cause cognitive impairments. Two substances have received heightened attention: 3,4-methylenedioxymethamphetamine (MDMA or 'ecstasy') and delta-9-tetrahydrocannabinol (THC or 'cannabis'). Preclinical evidence, as well as human studies examining regular ecstasy consumers, indicated that ecstasy use may have negative effects on learning, verbal memory and complex attentional functions. Cannabis has also been linked to symptoms of inattention and deficits in learning and memory. Most of the published studies in this field of research recruited participants by means of newspaper advertisements or by using word-of-mouth strategies. Because participants were usually aware that their drug use was critical to the research design, this awareness may have caused selection bias or created expectation effects. Focussing on attention and memory, this study aimed to assess cognitive functioning in a community-based representative sample that was derived from a large-scale epidemiological study. Available data concerning drug use history allowed sampling of subjects with varying degrees of lifetime drug experiences. Cognitive functioning was examined in 284 young participants, between 22 and 34 years. In general, their lifetime drug experience was moderate. Participants completed a neuropsychological test battery, including measures for verbal learning, memory and various attentional functions. Linear regression analysis was performed to investigate the relationship between cognitive functioning and lifetime experience of drug use. Ecstasy and cannabis use were significantly related to poorer episodic memory function in a dose-related manner. For attentional measures, decrements of small effect sizes were found. Error measures in tonic and phasic alertness tasks, selective attention task and vigilance showed small but significant effects, suggesting a stronger tendency to experience lapses of attention. No indication for differences in

  8. Treating attention in mild aphasia: evaluation of attention process training-II.

    Science.gov (United States)

    Murray, Laura L; Keeton, R Jessica; Karcher, Laura

    2006-01-01

    This study examined whether attention processing training-II [Sohlberg, M. M., Johnson, L., Paule, L., Raskin, S. A., & Mateer, C. A. (2001). Attention Process Training-II: A program to address attentional deficits for persons with mild cognitive dysfunction (2nd ed.). Wake Forest, NC: Lash & Associates.; APT-II], when applied in the context of a multiple baseline ABA design, would improve the attention abilities of RW, a patient with mild conduction aphasia and concomitant attention and working memory deficits. We also explored whether APT-II training would enhance RW's auditory comprehension, other cognitive abilities such as memory, and his and his spouse's perceptions of his daily attention and communication difficulties. With treatment, RW improved on trained attention tasks and made modest gains on standardized tests and probes that evaluated cognitive skills related to treatment activities. Nominal change in auditory comprehension and untrained attention and memory functions was observed, and neither RW nor his spouse reported noticeable improvements in his daily attention or communication abilities. These and previous findings indicate that structured attention retraining may enhance specific attention skills, but that positive changes in broader attention and untrained functions are less likely. As a result of reading this article, the participant will be able to: (1) summarize the previous literature regarding attention impairments and treatment approaches for patients with aphasia. (2) describe how Attention Processing Training-II affected the attention, auditory comprehension, and other cognitive abilities of the patient in this study.

  9. Joint Attention is Slowed in Older Adults.

    Science.gov (United States)

    Deroche, Thomas; Castanier, Carole; Perrot, Alexandra; Hartley, Alan

    2016-01-01

    The automatic propensity to orient to the location where other people are looking is the main way of establishing joint attention with others. Whereas joint attention has been mostly investigated with young adults, the present study examines age-related differences in the magnitude and time course of joint attention. Forty-three community-dwelling seniors and 43 younger adults performed a visuospatial task. The procedures closely follow those of gaze-cueing tasks commonly used to investigate joint attention. The findings revealed that a gaze-cueing effect occurs for both younger and older adults, with an equivalent average magnitude but with different time courses. The effect peaks later in older adults. Age-related differences in joint attention could be linked to a more general cognitive slowing rather than to poorer basic social skills. The present study adds to the growing interest in gerontological research regarding social attention.

  10. Anxiety and cognitive performance: attentional control theory.

    Science.gov (United States)

    Eysenck, Michael W; Derakshan, Nazanin; Santos, Rita; Calvo, Manuel G

    2007-05-01

    Attentional control theory is an approach to anxiety and cognition representing a major development of Eysenck and Calvo's (1992) processing efficiency theory. It is assumed that anxiety impairs efficient functioning of the goal-directed attentional system and increases the extent to which processing is influenced by the stimulus-driven attentional system. In addition to decreasing attentional control, anxiety increases attention to threat-related stimuli. Adverse effects of anxiety on processing efficiency depend on two central executive functions involving attentional control: inhibition and shifting. However, anxiety may not impair performance effectiveness (quality of performance) when it leads to the use of compensatory strategies (e.g., enhanced effort; increased use of processing resources). Directions for future research are discussed.

  11. An Immanent Critique of the Attention Economy

    OpenAIRE

    Claudio Celis Bueno

    2016-01-01

    The present article develops an immanent critique of the attention economy as a power apparatus. In particular, it contends that what Foucault (2009) defined as the passage from disciplinary societies to societies of security entails a transformation of the main function of human attention: whereas in disciplinary societies attention (or the gaze) was aimed at imposing continuous surveillance on each individual, societies of security conceive the gaze of each subject as a source of data which...

  12. An Immanent Critique of the Attention Economy.

    OpenAIRE

    Celis Bueno, Claudio

    2016-01-01

    The present article develops an immanent critique of the attention economy as a power apparatus. In particular, it contends that what Foucault (2009) defined as the passage from disciplinary societies to societies of security entails a transformation of the main function of human attention: whereas in disciplinary societies attention (or the gaze) was aimed at imposing continuous surveillance on each individual, societies of security conceive the gaze of each subject as a source of dat...

  13. Attention as foraging for information and reward

    Directory of Open Access Journals (Sweden)

    Sanjay G Manohar

    2013-11-01

    Full Text Available What is the purpose of attention? One avenue of research has led to the proposal that attention might be crucial for gathering information about the environment, while other lines of study have demonstrated attention's role in guiding behavior to rewarded options. Many experiments to study attention require participants to make a decision based on information acquired discretely at one point in time. In real-world situations, however, we are usually not presented with information about which option to select in such a manner. Rather we must initially search for information, weighing up reward values of options before we commit to a decision.Here, we propose that attention plays a role in both foraging for information and foraging for value.When foraging for information, attention is guided towards the unknown. When foraging for reward, attention is guided towards high reward values, allowing decision-making to proceed by accept-or-reject decisions on the currently attended option. According to this account, attention can be regarded as a low-cost alternative to moving around and engaging with the environment—teleforaging—before a decision is made to interact physically with the world.To track the timecourse of attention, we asked participants to seek out and acquire information about two gambles by directing their gaze, before choosing one of them. Participants often made multiple refixations on items before making a decision. Their eye movements revealed that early in the trial, attention was guided towards information, i.e. towards locations that reduced uncertainty about value. In contrast, late in the trial, attention was guided by expected value of the options. At the end of the decision period, participants were generally attending to the item they eventually chose. We suggest that attentional foraging shifts from an uncertainty-driven to a reward-driven mode during the evolution of a decision, allowing choices to be made by an engage

  14. Attention as foraging for information and value.

    Science.gov (United States)

    Manohar, Sanjay G; Husain, Masud

    2013-01-01

    What is the purpose of attention? One avenue of research has led to the proposal that attention might be crucial for gathering information about the environment, while other lines of study have demonstrated how attention may play a role in guiding behavior to rewarded options. Many experiments that study attention require participants to make a decision based on information acquired discretely at one point in time. In real-world situations, however, we are usually not presented with information about which option to select in such a manner. Rather we must initially search for information, weighing up reward values of options before we commit to a decision. Here, we propose that attention plays a role in both foraging for information and foraging for value. When foraging for information, attention is guided toward the unknown. When foraging for reward, attention is guided toward high reward values, allowing decision-making to proceed by accept-or-reject decisions on the currently attended option. According to this account, attention can be regarded as a low-cost alternative to moving around and physically interacting with the environment-"teleforaging"-before a decision is made to interact physically with the world. To track the timecourse of attention, we asked participants to seek out and acquire information about two gambles by directing their gaze, before choosing one of them. Participants often made multiple refixations on items before making a decision. Their eye movements revealed that early in the trial, attention was guided toward information, i.e., toward locations that reduced uncertainty about value. In contrast, late in the trial, attention was guided by expected value of the options. At the end of the decision period, participants were generally attending to the item they eventually chose. We suggest that attentional foraging shifts from an uncertainty-driven to a reward-driven mode during the evolution of a decision, permitting decisions to be made by

  15. Attention in schizophrenia and in epileptic psychosis

    Directory of Open Access Journals (Sweden)

    I.C.J Kairalla

    2008-01-01

    Full Text Available The adaptive behavior of human beings is usually supported by rapid monitoring of outstanding events in the environment. Some investigators have suggested that a primary attention deficit might trigger symptoms of schizophrenia. In addition, researchers have long discussed the relationship between schizophrenia and the schizophrenia-like psychosis of epilepsy (SLPE. On the basis of these considerations, the objective of the present study was to investigate attention performance of patients with both disorders. Patient age was 18 to 60 years, and all patients had received formal schooling for at least four years. Patients were excluded if they had any systemic disease with neurologic or psychiatric comorbidity, or a history of brain surgery. The computer-assisted TAVIS-2R test was applied to all patients and to a control group to evaluate and discriminate between selective, alternating and sustained attention. The TAVIS-2R test is divided into three parts: one for selective attention (5 min, the second for alternating attention (5 min, and the third for the evaluation of vigilance or sustained attention (10 min. The same computer software was used for statistical analysis of reaction time, omission errors, and commission errors. The sample consisted of 36 patients with schizophrenia, 28 with interictal SLPE, and 47 healthy controls. The results of the selective attention tests for both patient groups were significantly lower than that for controls. The patients with schizophrenia and SLPE performed differently in the alternating and sustained attention tests: patients with SLPE had alternating attention deficits, whereas patients with schizophrenia showed deficits in sustained attention. These quantitative results confirmed the qualitative clinical observations for both patient groups, that is, that patients with schizophrenia had difficulties in focusing attention, whereas those with epilepsy showed perseveration in attention focus.

  16. Time lapse imaging analysis of the effect of ER stress modulators on apoptotic cell assessed by caspase3/7 activation in NG108-15 cells

    Directory of Open Access Journals (Sweden)

    Ayako Saito

    2016-03-01

    Full Text Available This paper reports the data from the long term time lapse imaging of neuronal cell line NG108-15 that were treated with apoptosis inducer or various ER stress inducers. Use of the fluorescent reporter for activated caspase3/7 in combination with the conventional light microscope allowed us to investigate the time course of apoptosis induction at the single cell level. Quantitative as well as qualitative data are presented here to show the effect of two different ER stress modulating chemical compounds on caspase3/7-dependent apoptosis in neuronal cell line NG108-15 cells. Additional results and interpretation of our data concerning ER stress and apoptosis in NG108-15 cells can be found in Suga et al. (2015 [1] and in Suga et al. (2015 [2].

  17. Bayesian Markov-Chain-Monte-Carlo inversion of time-lapse crosshole GPR data to characterize the vadose zone at the Arrenaes Site, Denmark

    DEFF Research Database (Denmark)

    Scholer, Marie; Irving, James; Zibar, Majken Caroline Looms

    2012-01-01

    -chain-Monte-Carlo inversion approach with different priors. The ground-penetrating radar (GPR) geophysical method has the potential to provide valuable information on the hydraulic properties of the vadose zone because of its strong sensitivity to soil water content. In particular, recent evidence has suggested...... that the stochastic inversion of crosshole GPR traveltime data can allow for a significant reduction in uncertainty regarding subsurface van Genuchten–Mualem (VGM) parameters. Much of the previous work on the stochastic estimation of VGM parameters from crosshole GPR data has considered the case of steady......-state infiltration conditions, which represent only a small fraction of practically relevant scenarios. We explored in detail the dynamic infiltration case, specifically examining to what extent time-lapse crosshole GPR traveltimes, measured during a forced infiltration experiment at the Arreneas field site...

  18. Raputatud lapse sündroomi mõiste, olemus, tuvastamine ja ennetamine : [bakalaureusetöö] / Hettel Varik ; Tartu Ülikooli Õigusinstituut ; juhendaja: Endla Ülviste

    Index Scriptorium Estoniae

    Varik, Hettel

    2006-01-01

    Raputatud lapse sündroomi (RLS) mõiste, olemus ja probleemi teadvustamine, RLS-i põhjustanud tegevuse kui kuriteo tuvastamine, süüteo subjektiivse koosseisu sisustamine, kohtulahendid, RLS-i vältimise võimalikkusest, RLS-i tekitaja karistamine

  19. Application of RVA and Time-Lapse Photography to Explore Effects of Extent of Chlorination, Milling Extraction Rate, and Particle-Size Reduction of Flour on Cake-Baking Functionality

    Science.gov (United States)

    Three factors (extent of chlorination, milling extraction rate and particle-size reduction) in the cake-bakeing functionality of Croplan 594W flour were explored by Rapid Visco-Analyzer (RVA) and time-lapse photography. The extent of chlorination and milling extraction rate showed dramatic effects,...

  20. Sustained Attention Ability Affects Simple Picture Naming

    Directory of Open Access Journals (Sweden)

    Suzanne R. Jongman

    2017-07-01

    Full Text Available Sustained attention has previously been shown as a requirement for language production. However, this is mostly evident for difficult conditions, such as a dual-task situation. The current study provides corroborating evidence that this relationship holds even for simple picture naming. Sustained attention ability, indexed both by participants’ reaction times and individuals’ hit rate (the proportion of correctly detected targets on a digit discrimination task, correlated with picture naming latencies. Individuals with poor sustained attention were consistently slower and their RT distributions were more positively skewed when naming pictures compared to individuals with better sustained attention. Additionally, the need to sustain attention was manipulated by changing the speed of stimulus presentation. Research has suggested that fast event rates tax sustained attention resources to a larger degree than slow event rates. However, in this study the fast event rate did not result in increased difficulty, neither for the picture naming task nor for the sustained attention task. Instead, the results point to a speed-accuracy trade-off in the sustained attention task (lower accuracy but faster responses in the fast than in the slow event rate, and to a benefit for faster rates in the picture naming task (shorter naming latencies with no difference in accuracy. Performance on both tasks was largely comparable, supporting previous findings that sustained attention is called upon during language production.

  1. Imaging high stage river-water intrusion into a contaminated aquifer along a major river corridor using 2-D time-lapse surface electrical resistivity tomography

    Science.gov (United States)

    Wallin, E. L.; Johnson, T. C.; Greenwood, W. J.; Zachara, J. M.

    2013-03-01

    The Hanford 300 Area is located adjacent to the Columbia River in south-central Washington State, USA, and was a former site for nuclear fuel processing operations. Waste disposal practices resulted in persistent unsaturated zone and groundwater contamination, the primary contaminant of concern being uranium. Uranium behavior at the site is intimately linked with river stage driven groundwater-river water exchange such that understanding the nature of river water intrusion into the 300 Area is critical for predicting uranium desorption and transport. In this paper, we use 2-D surface-based time-lapse electrical resistivity tomography (ERT) to image the inland intrusion of river water during high stage conditions. We inverted approximately 1200 data sets (400 per line over three lines) using high performance computing resources to produce a time-lapse sequence of changes in bulk conductivity caused by river water intrusion during the 2011 spring runoff cycle over approximately 125 days. To invert the data, we use an image differencing approach that does not require regularization in the time dimension, enabling the inversion to accommodate the sharp, time varying contrasts in conductivity imposed by the moving water table. The resulting time series for each mesh element was then analyzed using common time series analysis to reveal the timing and location of river water intrusion beneath each line. The results reveal nonuniform flows characterized by preferred flow zones where river water enters and exits quickly with stage increase and decrease, and low permeability zones with broader bulk conductivity "break through" curves and longer river water residence times.

  2. MONITORING EROSION OF STONE SURFACES USING TIME-LAPSE AND PTM PHOTOGRAPHY: FIELD STUDY OF A 14TH CENTURY MONASTERY IN YORKSHIRE

    Science.gov (United States)

    Doehne, E.; Pinchin, S.

    2009-12-01

    Evaluating stone weathering rates and their relationship to environmental fluctuations is an important challenge in understanding the critical zone and also in efforts to prevent the loss of important cultural heritage in stone, such as monuments, sculpture and archaeological sites. Repeat photography has been widely used to evaluate geological processes such as the retreat of glaciers and the weathering of stone surfaces. However, a fundamental difficulty is that the images are often shot under differing lighting conditions, making the interpretation of stone surface loss particularly challenging. Two developments in photographic documentation show promise for improving the situation. One is the use of digital time-lapse methods to provide more frequent images to correlate stone surface loss with ongoing environmental changes. The other is a relatively new method known as polynomial transform mapping (PTM), which integrates multiple photographs taken at different angles to document more comprehensively the texture of stone surfaces. Using Java-based software, the viewer can control the precise angle of the light source in an interpolated, high-quality image. PTM can produce raking light images from any angle, as well as images with ‘normal’ illumination. We present here results based on several years of macro-photography, time-lapse imaging, and PTM imaging of rapidly eroding stone surfaces at the site of Howden Minster in Yorkshire, UK, which suffers from salt weathering. The images show that surface loss is episodic rather than continuous and in some cases is related to unusual environmental conditions, such as high winds and condensation events. Damage was also found to be synchronous, with surface change (flaking, granular disintegration, and loss of flakes) occurring at the same time in different stone blocks. Crystallization pressure from phase transitions in magnesium sulfate salts appears to be the main cause of the loss of stone surfaces.

  3. Surface Air Temperature Fluctuations and Lapse Rates on Olivares Gamma Glacier, Rio Olivares Basin, Central Chile, from a Novel Meteorological Sensor Network

    Directory of Open Access Journals (Sweden)

    Edward Hanna

    2017-01-01

    Full Text Available Empirically based studies of glacier meteorology, especially for the Southern Hemisphere, are relatively sparse in the literature. Here, we use an innovative network of highly portable, low-cost thermometers to report on high-frequency (1-min time resolution surface air temperature fluctuations and lapse rates (LR in a ~800-m elevational range (from 3,675 to 4,492 m a.s.l. across the glacier Olivares Gamma in the central Andes, Chile. Temperatures were measured during an intense field campaign in late Southern summer, 19–27 March 2015, under varying weather conditions. We found a complex dependence of high-frequency LR on time of day, topography, and wider meteorological conditions, with hourly temperature variations during this week that were probably mainly associated with short- and long-wave radiation changes and not with wind speed/direction changes. Using various pairs of sites within our station network, we also analyze spatial variations in LR. Uniquely in this study, we compare temperatures measured at heights of 1-m and 2-m above the glacier surface for the network of five sites and found that temperatures at these two heights occasionally differed by more than ±4°C during the early afternoons, although the mean temperature difference is much smaller (~0.3°C. An implication of our results is that daily, hourly, or even monthly averaged LR may be insufficient for feeding into accurate melt models of glacier change, with the adoption of subhourly (ideally 1–10-min resolution LR likely to prove fruitful in developing new innovative high-time-resolution melt modelling. Our results are potentially useful as input LR for local glacier melt models and for improving the understanding of lapse rate fluctuations and glacier response to climate change.

  4. Noninferiority, randomized, controlled trial comparing embryo development using media developed for sequential or undisturbed culture in a time-lapse setup.

    Science.gov (United States)

    Hardarson, Thorir; Bungum, Mona; Conaghan, Joe; Meintjes, Marius; Chantilis, Samuel J; Molnar, Laszlo; Gunnarsson, Kristina; Wikland, Matts

    2015-12-01

    To study whether a culture medium that allows undisturbed culture supports human embryo development to the blastocyst stage equivalently to a well-established sequential media. Randomized, double-blinded sibling trial. Independent in vitro fertilization (IVF) clinics. One hundred twenty-eight patients, with 1,356 zygotes randomized into two study arms. Embryos randomly allocated into two study arms to compare embryo development on a time-lapse system using a single-step medium or sequential media. Percentage of good-quality blastocysts on day 5. Percentage of day 5 good-quality blastocysts was 21.1% (standard deviation [SD] ± 21.6%) and 22.2% (SD ± 22.1%) in the single-step time-lapse medium (G-TL) and the sequential media (G-1/G-2) groups, respectively. The mean difference (-1.2; 95% CI, -6.0; 3.6) between the two media systems for the primary end point was less than the noninferiority margin of -8%. There was a statistically significantly lower number of good-quality embryos on day 3 in the G-TL group [50.7% (SD ± 30.6%) vs. 60.8% (SD ± 30.7%)]. Four out of the 11 measured morphokinetic parameters were statistically significantly different for the two media used. The mean levels of ammonium concentration in the media at the end of the culture period was statistically significantly lower in the G-TL group as compared with the G-2 group. We have shown that a single-step culture medium supports blastocyst development equivalently to established sequential media. The ammonium concentrations were lower in the single-step media, and the measured morphokinetic parameters were modified somewhat. NCT01939626. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  5. In Vivo Time-Lapse Imaging in the Zebrafish Lateral Line: A Flexible, Open-Ended Research Project for an Undergraduate Neurobiology Laboratory Course.

    Science.gov (United States)

    Marra, Molly H; Tobias, Zachary J C; Cohen, Hannah R; Glover, Greta; Weissman, Tamily A

    2015-01-01

    The lateral line sensory system in fish detects movements in the water and allows fish to respond to predators, prey, and other stimuli. As the lateral line forms in the first two days of zebrafish development, axons extend caudally along the lateral surface of the fish, eventually forming synapses with hair cells of neuromasts. Growing lateral line axons are located superficially under the skin and can be labeled in living zebrafish using fluorescent protein expression. This system provides a relatively straightforward approach for in vivo time-lapse imaging of neuronal development in an undergraduate setting. Here we describe an upper-level neurobiology laboratory module in which students investigate aspects of axonal development in the zebrafish lateral line system. Students learn to handle and image living fish, collect time-lapse videos of moving mitochondria, and quantitatively measure mitochondrial dynamics by generating and analyzing kymographs of their movements. Energy demands may differ between axons with extending growth cones versus axons that have already reached their targets and are forming synapses. Since relatively little is known about this process in developing lateral line axons, students generate and test their own hypotheses regarding how mitochondrial dynamics may differ at two different time points in axonal development. Students also learn to incorporate into their analysis a powerful yet accessible quantitative tool, the kymograph, which is used to graph movement over time. After students measure and quantify dynamics in living fish at 1 and 2 days post fertilization, this module extends into independent projects, in which students can expand their studies in a number of different, inquiry-driven directions. The project can also be pared down for courses that wish to focus solely on the quantitative analysis (without fish handling), or vice versa. This research module provides a useful approach for the design of open-ended laboratory

  6. Improvements of a COMS Land Surface Temperature Retrieval Algorithm Based on the Temperature Lapse Rate and Water Vapor/Aerosol Effect

    Directory of Open Access Journals (Sweden)

    A-Ra Cho

    2015-02-01

    Full Text Available The National Meteorological Satellite Center in Korea retrieves land surface temperature (LST by applying the split-window LST algorithm (CSW_v1.0 to Communication, Ocean, and Meteorological Satellite (COMS data. Considerable errors were detected under conditions of high water vapor content or temperature lapse rates during validation with Moderate Resolution Imaging Spectroradiometer (MODIS LST because of the too simplified LST algorithm. In this study, six types of LST retrieval equations (CSW_v2.0 were developed to upgrade the CSW_v1.0. These methods were developed by classifying “dry,” “normal,” and “wet” cases for day and night and considering the relative sizes of brightness temperature difference (BTD values. Similar to CSW_v1.0, the LST retrieved by CSW_v2.0 had a correlation coefficient of 0.99 with the prescribed LST and a slightly larger bias of −0.03 K from 0.00K; the root mean square error (RMSE improved from 1.41 K to 1.39 K. In general, CSW_v2.0 improved the retrieval accuracy compared to CSW_v1.0, especially when the lapse rate was high (mid-day and dawn and the water vapor content was high. The spatial distributions of LST retrieved by CSW_v2.0 were found to be similar to the MODIS LST independently of the season, day/night, and geographic locations. The validation using one year’s MODIS LST data showed that CSW_v2.0 improved the retrieval accuracy of LST in terms of correlations (from 0.988 to 0.989, bias (from −1.009 K to 0.292 K, and RMSEs (from 2.613 K to 2.237 K.

  7. Effect of cholinesterase inhibitors on attention.

    Science.gov (United States)

    Pepeu, Giancarlo; Giovannini, Maria Grazia; Bracco, Laura

    2013-03-25

    Advantages and limits of the use of cholinesterase inhibitors (ChEI) in Alzheimer's disease (AD) are well established. Their effects result from an increase in extracellular acetylcholine (ACh) whose hydrolysis is prevented by cholinesterase inhibition. In this way, the cholinergic deficit which characterizes AD may be corrected. This overview discusses which components of the cognitive process are improved by ChEI administration. In animal experiments, the increase in ACh release, detected in brain areas during behavioral tasks designed to tax attentional processes, demonstrates that an activation of cholinergic neurons underlies arousal and attention. Since arousal and attention depend on activation of the forebrain cholinergic system, it is to be expected that the loss of cholinergic neurons occurring in AD may lead to impairment of the attentional processes. Indeed, a consensus exists that attention is the first non-memory domain to be affected in AD, before deficits in language and visuo-spatial functions. The difficulties with daily living, which occur even in mild AD, may be related to attentional deficits. ChEIs, by restoring the cholinergic activity, should improve attention. If the cognitive changes resulting from ChEI treatment in AD patients are assessed with appropriate tests or selected items of the scales, a predominant effect on attention and executive functions emerges. In a group of 121 subjects with mild to moderate AD, (MMSE score 21.88 ± 3.63) followed in the Alzheimer Unit in Florence, after a year of treatment with standard doses of ChEIs, it was observed a stabilization of the disease, characterized by no changes of the tests evaluating attention and executive functions but a worsening of those involving memory mechanisms. These findings suggest that ChEI treatment preserves attention more than memory. Finally, the electrophysiological and neurochemical mechanisms through which the activation of the cholinergic forebrain neurons enhance

  8. Attention manipulation for naval tactical picture compilation

    NARCIS (Netherlands)

    Bosse, T.; Lambalgen, R. van; Maanen, P.P.; Treur, J.

    2009-01-01

    This paper discusses and evaluates an agent model that is able to manipulate the visual attention of a human, in order to support naval crew. The agent model consists of four submodels, including a model to reason about a subject's attention. The model was evaluated based on a practical case study

  9. Attention-training with children from socioeconomically ...

    African Journals Online (AJOL)

    Objective: Attention is a core process underlying competence in higher-order cognitive abilities. Previous research suggests that healthy children from low socioeconomic status (SES) backgrounds perform poorly, relative to those from higher SES backgrounds, on tasks assessing attentional abilities. In this pilot study, we ...

  10. Spatial attention systems in spatial neglect.

    Science.gov (United States)

    Karnath, Hans-Otto

    2015-08-01

    It has been established that processes relating to 'spatial attention' are implemented at cortical level by goal-directed (top-down) and stimulus-driven (bottom-up) networks. Spatial neglect in brain-damaged individuals has been interpreted as a distinguished exemplar for a disturbance of these processes. The present paper elaborates this assumption. Functioning of the two attentional networks seem to dissociate in spatial neglect; behavioral studies of patients' orienting and exploration behavior point to a disturbed stimulus-driven but preserved goal-directed attention system. When a target suddenly appears somewhere in space, neglect patients demonstrate disturbed detection and orienting if it is located in contralesional direction. In contrast, if neglect patients explore a scene with voluntarily, top-down controlled shifts of spatial attention, they perform movements that are oriented into all spatial directions without any direction-specific disturbances. The paper thus argues that not the top-down control of spatial attention itself, rather a body-related matrix on top of which this process is executed, seems affected. In that sense, the traditional role of spatial neglect as a stroke model for 'spatial attention' requires adjustment. Beyond its insights into the human stimulus-driven attentional system, the disorder most notably provides vistas in how our brain encodes topographical information and organizes spatially oriented action - including the top-down control of spatial attention - in relation to body position. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Reading Comprehension, Extended Processing and Attention Dysfunction.

    Science.gov (United States)

    Cherkes-Julkowski, Miriam; Stolzenberg, Jonathan

    This study investigated the role of executive function in children with attention deficit disorders (ADD) by comparing differences resulting when diagnostic measures of reading comprehension consisting of either short or long passages were used. Subjects (all in grades 1-12) were grouped as having an attention deficit disorder (ADD) and not taking…

  12. Attentional neural networks impairment in healthy aging

    NARCIS (Netherlands)

    Vazquez-Marrufo, Manuel; Luisa Benitez, Maria; Rodriguez-Gomez, Guillermo; Galvao-Carmona, Alejandro; Fernandez-Del Olmo, Aaron; Vaquero-Casares, Encarnacion

    2011-01-01

    Introduction. Diverse evidences have shown that the process of natural aging causes a decline in different cognitive functions, including among them the attentional process. Aim. To determine how the healthy aging affects to the different attentional networks. Subjects and methods. Two groups: young

  13. Attention Deficit Disorder (ADHD): Primary school teachers ...

    African Journals Online (AJOL)

    Hennie

    A self-administered questionnaire, the Knowledge of Attention-Deficit Disorder Scale. (KADDS), which measures the ... Attention Deficit Disorder (ADHD) is characterised by“a chronic and pervasive pattern of developmentally inappropriate levels of ..... (86.9%), communication as intervention (86.4%), academic and social ...

  14. Impaired Visual Attention in Children with Dyslexia.

    Science.gov (United States)

    Heiervang, Einar; Hugdahl, Kenneth

    2003-01-01

    A cue-target visual attention task was administered to 25 children (ages 10-12) with dyslexia. Results showed a general pattern of slower responses in the children with dyslexia compared to controls. Subjects also had longer reaction times in the short and long cue-target interval conditions (covert and overt shift of attention). (Contains…

  15. Habitual attention in older and young adults.

    Science.gov (United States)

    Jiang, Yuhong V; Koutstaal, Wilma; Twedell, Emily L

    2016-12-01

    Age-related decline is pervasive in tasks that require explicit learning and memory, but such reduced function is not universally observed in tasks involving incidental learning. It is unknown if habitual attention, involving incidental probabilistic learning, is preserved in older adults. Previous research on habitual attention investigated contextual cuing in young and older adults, yet contextual cuing relies not only on spatial attention but also on context processing. Here we isolated habitual attention from context processing in young and older adults. Using a challenging visual search task in which the probability of finding targets was greater in 1 of 4 visual quadrants in all contexts, we examined the acquisition, persistence, and spatial-reference frame of habitual attention. Although older adults showed slower visual search times and steeper search slopes (more time per additional item in the search display), like young adults they rapidly acquired a strong, persistent search habit toward the high-probability quadrant. In addition, habitual attention was strongly viewer-centered in both young and older adults. The demonstration of preserved viewer-centered habitual attention in older adults suggests that it may be used to counter declines in controlled attention. This, in turn, suggests the importance, for older adults, of maintaining habit-related spatial arrangements. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  16. Why visual attention and awareness are different

    NARCIS (Netherlands)

    Lamme, V.A.F.

    2003-01-01

    Now that the study of consciousness is warmly embraced by cognitive scientists, much confusion seems to arise between the concepts of visual attention and visual awareness. Often, visual awareness is equated to what is in the focus of attention. There are, however, two sets of arguments to separate

  17. Attentional control and competition between episodic representations

    NARCIS (Netherlands)

    Akyürek, Elkan G.; Schubö, Anna; Hommel, Bernhard

    The relationship between attentional control and episodic representation was investigated in six experiments that employed a variant of the classic attentional blink paradigm. We introduced a task-irrelevant (unpredictive) color match between the first and second target stimulus in a three-stream

  18. Touchscreen Sustained Attention Task (SAT) for Rats.

    Science.gov (United States)

    Bangasser, Debra A; Wicks, Brittany; Waxler, David E; Eck, Samantha R

    2017-09-15

    Sustained attention is the ability to monitor intermittent and unpredictable events over a prolonged period of time. This attentional process subserves other aspects of cognition and is disrupted in certain neurodevelopmental, neuropsychiatric, and neurodegenerative disorders. Thus, it is clinically important to identify mechanisms that impair and improve sustained attention. Such mechanisms are often first discovered using rodent models. Therefore, several behavior procedures for testing aspects of sustained attention have been developed for rodents. One, first described by McGaughy and Sarter (1995), called the sustained attention task (SAT), trains rats to distinguish between signal (i.e., brief light presentation) and non-signal trials. The signals are short and thus require careful attention to be perceived. Attentional demands can be increased further by introducing a distractor (e.g., flashing houselight). We have modified this task for touchscreen operant chambers, which are configured with a touchscreen on one wall that can present stimuli and record responses. Here we detail our protocol for SAT in touchscreen chambers. Additionally, we present standard measures of performance in male and female Sprague-Dawley rats. Comparable performance on this task in both sexes highlights its use for attention studies, especially as more researchers are including female rodents in their experimental design. Moreover, the easy implementation of SAT for the increasingly popular touchscreen chambers increases its utility.

  19. Longterm visual associations affect attentional guidance

    NARCIS (Netherlands)

    Olivers, C.N.L.

    2011-01-01

    When observers perform a visual search task, they are assumed to adopt an attentional set for what they are looking for. The present experiment investigates the influence of long-term visual memory associations on this attentional set. On each trial, observers were asked to search a display for a

  20. Trajectories of CBCL Attention Problems in childhood

    NARCIS (Netherlands)

    Robbers, S.C.C.; Oort, F.V.A. van; Polderman, T.J.C.; Bartels, M.; Boomsma, D.I.; Verhulst, F.C.; Huizink, A.C.

    2011-01-01

    The first aim of this study was to identify developmental trajectories of Attention Problems in twins followed from age 6 to 12 years. Second, we investigated whether singletons follow similar trajectories. Maternal longitudinal ratings on the Attention Problems (AP) subscale of the Child Behavior