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Sample records for arengukeskkonna mju lapse

  1. AMS Time Lapse Installation

    NASA Image and Video Library

    A time lapse video compilation of the installation of the Alpha Magnetic Spectrometer on the International Space Station’s starboard truss using the station’s robotic arm, Canadarm2, during the...

  2. Milky Way time lapse

    NASA Image and Video Library

    2015-08-09

    iss044e045215 (08/09/2015)-- View (part of a time lapse sequence) of stars in the Milky Way Galaxy visible over an Earth limb as seen by the Expedition 44 crew. Astronaut Kjell Lindgren captured a lightning strike from space so bright that it lights up the space station’s solar panels. He posted this on Twitter and Instagram on Sept. 2 saying "Large lightning strike on Earth lights up or solar panels."

  3. A-3 Construction Time Lapse

    NASA Technical Reports Server (NTRS)

    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.

  4. A-3 Construction Time Lapse

    NASA Technical Reports Server (NTRS)

    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.

  5. Rim Fire Time Lapse, August 2013

    NASA Image and Video Library

    Time-lapse photography shows various perspectives of the 2013 Rim Fire, as viewed from Yosemite National Park. The first part of this video is from the Crane Flat Helibase. The fire is currently bu...

  6. Crawler-Transporter Time-Lapse

    NASA Image and Video Library

    Time-lapse video shows crawler-transporter No. 2 traveling from the Vehicle Assembly Building to Launch Pad 39A at NASA's Kennedy Space Center in Florida. The move was performed by the Ground Syste...

  7. Mental Lapses and Event-Related Potentials.

    DTIC Science & Technology

    1989-11-01

    AD-A219 454 A9 MENTAL LAPSES AND i’: EVENT-RELATED POTENTIALS R.R. STANNY 41 DTIC LECTE MAR2 aalAs ospace Medical Research Lzhoratory Naval Air... Mental Lapses and Event-Related Potentials 12. PERSONAL AUTHOR(S) R. R. Stannv 13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (Yeir, Month...of perception and judgment. Several rapid methods of estimating mental state from ERP data were examined. FINDINGS All of the procedures examined

  8. QueSST Time-lapse

    NASA Image and Video Library

    2017-02-27

    Quiet Supersonic Technology (QueSST) X-plane in the 8x6 Supersonic Wind Tunnel at NASA Glenn Research Center. This time-lapse shows the model support structure buildup and balance checkout as well as the installation of the model in the test section.

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

    ERIC Educational Resources Information Center

    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…

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

    ERIC Educational Resources Information Center

    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…

  11. Lapse resistance in the verbal letter reporting task.

    PubMed

    Arditi, Aries

    2006-04-01

    Lapses, or misreporting errors, can affect accuracy of threshold measurements. Assumptions about lapse rate, especially in untrained observers, have consequently guided the design of at least one clinical psychophysical test. Lapse rate was assessed using a verbal letter identification paradigm like that used in visual acuity and letter contrast sensitivity testing. Subjects occasionally made slip-of-the tongue errors but spontaneously corrected them. Lapse rate (excluding such errors) was 0-3 errors per 1,536 (average rate of 0.0005). In this common clinical paradigm, in which observers set their reporting pace, and where opportunity to amend responses is available, lapse rate is negligible.

  12. Pupil Diameter Tracks Lapses of Attention

    PubMed Central

    Murphy, Peter R.; Nieuwenhuis, Sander

    2016-01-01

    Our ability to sustain attention for prolonged periods of time is limited. Studies on the relationship between lapses of attention and psychophysiological markers of attentional state, such as pupil diameter, have yielded contradicting results. Here, we investigated the relationship between tonic fluctuations in pupil diameter and performance on a demanding sustained attention task. We found robust linear relationships between baseline pupil diameter and several measures of task performance, suggesting that attentional lapses tended to occur when pupil diameter was small. However, these observations were primarily driven by the joint effects of time-on-task on baseline pupil diameter and task performance. The linear relationships disappeared when we statistically controlled for time-on-task effects and were replaced by consistent inverted U-shaped relationships between baseline pupil diameter and each of the task performance measures, such that most false alarms and the longest and most variable response times occurred when pupil diameter was both relatively small and large. Finally, we observed strong linear relationships between the temporal derivative of pupil diameter and task performance measures, which were largely independent of time-on-task. Our results help to reconcile contradicting findings in the literature on pupil-linked changes in attentional state, and are consistent with the adaptive gain theory of locus coeruleus-norepinephrine function. Moreover, they suggest that the derivative of baseline pupil diameter is a potentially useful psychophysiological marker that could be used in the on-line prediction and prevention of attentional lapses. PMID:27768778

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

    PubMed

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

    2017-04-05

    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 < 0.02). Interestingly, greater 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.

  14. New Siemens Research Turbine - time lapse

    SciTech Connect

    2009-01-01

    The National Renewable Energy Laboratory (NREL) and Siemens Energy Inc. recently commissioned a new 2.3 megawatt Siemens wind turbine at NREL's National Wind Technology Center. This video shows a time lapse of the installation. The turbine is the centerpiece of a multi-year project to study the performance and aerodynamics of a new class of large, land-based machines — in what will be the biggest government-industry research partnership for wind power generation ever undertaken in the U.S.

  15. Time-lapse photogrammetry in geomorphic studies

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed

    Tsan, Min-Fu; Grabenbauer, Michael; Nguyen, Yen

    2016-01-01

    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.

  17. Choosing the best embryo by time lapse versus standard morphology.

    PubMed

    Kirkegaard, Kirstine; Ahlström, Aishling; Ingerslev, Hans Jakob; Hardarson, Thorir

    2015-02-01

    Within the past few years the morphological evaluation of in vitro fertilized embryos has been extended to include continuous surveillance, enabled by the introduction of time-lapse incubators developed specifically for IVF treatment. As a result time-lapse monitoring has been implemented in many clinics worldwide. The proposed benefits compared with culture in a standard incubator and fixed time-point evaluation are uninterrupted culture, a flexible workflow in the laboratory, and improved embryo selection. The latter is based on the reasonable assumption that more frequent observations will provide substantially more information on the relationship between development, timing, and embryo viability. Several retrospective studies have confirmed a relationship between time-lapse parameters and embryo viability evaluated by developmental competence, aneuploidy, and clinical pregnancy. Furthermore a much anticipated randomized study has shown improved pregnancy rates (PRs) after culture in a time-lapse incubator combined with selection using a hierarchical time-lapse selection model. At present this is the only randomized study on possible benefits of time lapse in human embryology. Strict evidence may still seem too weak to introduce time lapse in routine clinical setting. This aim of this review is therefore to perform a balanced discussion of the evidence for time-lapse monitoring. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  18. How does coping help people resist lapses during smoking cessation?

    PubMed

    O'Connell, Kathleen A; Hosein, Vanessa L; Schwartz, Joseph E; Leibowitz, Ruth Q

    2007-01-01

    To determine whether types of coping strategies have differential effects on preventing lapses and lowering urge levels and to investigate mechanisms by which coping strategies prevent lapses during smoking cessation. Sixty-one respondents performed ecological momentary assessment using palm-top computers and tape recorders to report their coping strategies and urge levels before and after temptations to smoke. Multilevel linear regression models were used to compare the effects of individual strategy types with the average strategy. Lapses versus resisted temptations and changes in urge levels. Number of strategies significantly predicted resisting smoking and change in urge levels. Compared with the effect of the average strategy, movement/exercise was marginally worse at preventing lapses, and food/drink was marginally related to higher postcoping urge levels. Although using multiple coping strategies helps people resist the urge to smoke, no particular coping strategy works better than any other. Coping strategies prevent lapses by reducing high urge levels during temptations.

  19. The lapse-rate feedback leads to polar temperature amplification.

    NASA Astrophysics Data System (ADS)

    Grand Graversen, Rune; Langen, Peter; Mauritsen, Thorsten

    2014-05-01

    The atmospheric temperature will change in response to a radiative forcing of the climate system, but the temperature change may not be constant with height in the atmosphere. The dependence of the temperature change on hight gives rise to the lapse-rate feedback. In a warmer climate, the saturated mixing ratio of water vapour increases more at lower than at upper levels in the troposphere. Therefore due to enhanced latent heat release, the atmosphere tends to warm more in the upper than in the lower troposphere in regions where strong convection is present, such as at tropical latitudes. This results in enhanced radiation back to space, and in a more efficient cooling of the Earth system. This is contributing to a negative lapse-rate feedback. The opposite situation prevails at the high latitudes where stable stratification conditions in the lower troposphere result in a larger warming of the surface-near atmosphere than of the upper troposphere. This is contributing to a positive lapse-rate feedback. Hence the lapse-rate feedback is assumed to be negative at low, and positive at high latitudes. Here we explore the lapse-rate feedback and its effect on the climate system using a slab-ocean climate model, the Community Climate System Model version 4. By locking the temperature change throughout the troposphere to that at the surface in calls to the radiation code, the lapse-rate feedback is suppressed on-line in the model. Doubling-of-CO2 experiments where the lapse-rate feedback is suppressed are compared with experiments where it is retained. In a similar way the surface-albedo feedback is suppressed by keeping the surface albedo fixed in the entire model system. On the basis of model versions where either one or both of the feedbacks are suppressed, we are able to separate the effect of the surface-albedo and lapse-rate feedback. For instance we can estimate the contribution to the polar temperature amplification due to each of the feedbacks. The results show

  20. Saturn Time Lapse - Target of Opportunity

    NASA Astrophysics Data System (ADS)

    Westphal, J.

    1990-12-01

    This program will obtain sets of exposures of Saturn in several spectral bands over a time span of about a week. By selecting filters that are sensitive to atmospheric processes (methane absorption and molecular scattering), the dynamic behavior can be mapped at several altitudes within the Saturnian atmosphere. This sequence will utilize time lapse sequences in chip PC-6 to continue monitoring motions associated with the great white spot that was discovered in late September. These observations will allow us to follow the evolution of the storm. Observation is broken up into 2 parts - part 1 = Get as many orbits as possible in a 31 orbit timeframe. Part 2 = Get as many orbits as possible in a 16 orbit timeframe. Use the FGS SAA avoidance contour versus the WF/PC SAA avoidance contour. During orbits with FGS SAA impact, obtain earth flats, using seq FLATn. Take flats in each filter (FLAT1->FLAT6) then go back and take second set in each filter, time permitting.

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

    PubMed

    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

    2017-01-01

    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 change is uncertain because of poor constraints on high-elevation temperature during past climate states. We present a 25,000-year temperature reconstruction from Mount Kenya, East Africa, which demonstrates that cooling during the Last Glacial Maximum was amplified with elevation and hence that the lapse rate was significantly steeper than today. Comparison of our data with paleoclimate simulations indicates that state-of-the-art models underestimate this lapse-rate change. Consequently, future high-elevation tropical warming may be even greater than predicted.

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

    PubMed Central

    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.

    2017-01-01

    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 change is uncertain because of poor constraints on high-elevation temperature during past climate states. We present a 25,000-year temperature reconstruction from Mount Kenya, East Africa, which demonstrates that cooling during the Last Glacial Maximum was amplified with elevation and hence that the lapse rate was significantly steeper than today. Comparison of our data with paleoclimate simulations indicates that state-of-the-art models underestimate this lapse-rate change. Consequently, future high-elevation tropical warming may be even greater than predicted. PMID:28138544

  3. Time-lapse seismic noise correlation tomography at Valhall

    NASA Astrophysics Data System (ADS)

    de Ridder, S. A. L.; Biondi, B. L.; Clapp, R. G.

    2014-09-01

    We show that a reliable and statistically significant group velocity time-lapse difference between 2004 and 2010 can be retrieved from ambient seismic noise in an offshore hydrocarbon exploitation setting. We performed a direct comparison of Scholte wave group velocity images obtained using regularized tomography. We characterize the expected variation in group velocity images from the 2004 or 2010 recordings that result from fluctuations in the cross correlations by looking at cross correlations of portions of the recordings. We prove that the time-lapse difference is statistically significant. The time-lapse group velocity image from ambient noise data shows strong similarities with a time-lapse phase velocity map obtained from controlled source data. The most striking features are a northern and a southern group velocity increase due to compaction and subsidence as a result of reservoir production.

  4. NEA Scout Solar Sail: Half-scale Fold Time Lapse

    NASA Image and Video Library

    In this time lapse, the Near-Earth Asteroid Scout (NEA Scout) CubeSat team rolls a half-scale prototype of the small satellite's solar sail in preparation for a deployment test. During its mission,...

  5. Atlantis Time-Lapse Move to KSC Visitor Complex

    NASA Image and Video Library

    Time-lapse cameras captured space shuttle Atlantis making a 10-mile trek from the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida to the Kennedy Space Center Visitor Complex whe...

  6. Time-Lapsed Animation of a Mercury Day

    NASA Image and Video Library

    Parts of Prokofiev crater (center) and Kandinsky crater (upper left side of Prokofiev) stay in darkness, making it possible for ice to persist on the surface. This time-lapsed animation represents ...

  7. ISS Expedition 42 Time Lapse Video of Earth and Aurora

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e214317 - iss042e215156). Shows Earth views and aurora. Solar Array Wing (SAW) in foreground.

  8. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e260338 - iss042e261334). Shows night time Earth views taken from the Cupola module.

  9. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e238532 - iss042e239150). Shows Earth views. Solar Array Wing (SAW) in foreground.

  10. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2014-09-29

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss041e37762 - iss041e39788). Shows Earth and aurora views. Partial views of ISS in and out of view.

  11. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e210380 - iss042e211441). Shows Earth views. Solar Array Wing (SAW) in and out of view.

  12. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    s time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e207712 - iss042e209132 ). Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  13. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e211498 - iss042e212135). Shows Earth views. Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground

  14. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e116561 - iss042e117265). Shows Earth views. Solar Array Wing (SAW) in foreground.

  15. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e290689 - iss042e291289). Shows Earth views. Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  16. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e203119 - iss042e203971). Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  17. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (iss042e071550 - iss042e072050). Shows Earth views over Africa, Sinai, Saudi Arabia, Jordan and Israel.

  18. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e212874 - iss042e213080). Shows Earth views. Solar Array Wing (SAW) in foreground.

  19. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e285752 - iss042e286830). Shows Earth views. Solar Array Wing (SAW) in foreground.

  20. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e170341 - iss042e171462). Shows Earth views. Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  1. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e110489 - iss042e111902). Shows Earth views. Solar Array Wing (SAW) in foreground.

  2. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e193144 - iss042e194102). Shows Earth views. Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  3. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e177446 - iss042e178444 ). Shows Earth views. Solar Array Wing (SAW) in foreground.

  4. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e215401 -iss042e215812). Shows Earth views. Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  5. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e249923 - iss042e250759). Shows Earth views. Space Station Remote Manipulator system (SSRMS) or Canadarm in foreground.

  6. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e324104 - iss042e325631). Shows Earth views. Soyuz and Progress spacecrafts come into view.

  7. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e190769 - iss042e191096). Shows Earth views. Solar Array Wing (SAW) in foreground.

  8. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e162807 - iss042e163936). Shows Earth views. Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  9. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e308288 - iss042e309536). Shows Earth views taken from a window aboard the International Space Station (ISS).

  10. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e209133 - iss042e210379). Shows Earth views. Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  11. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e334978 - iss042e335976). Shows Earth views. Solar Array Wing (SAW) comes into view.

  12. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e244330 - iss042e245101). Shows Earth views. Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  13. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e330173 - iss042e331530). Shows Earth views. Solar Array Wing (SAW) in foreground.

  14. 77 FR 38396 - Agency Information Collection (Notice of Lapse-Government Life Insurance) Activities Under OMB...

    Federal Register 2010, 2011, 2012, 2013, 2014

    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...

  15. Are attention lapses related to d-amphetamine liking?

    PubMed Central

    McCloskey, Michael; Palmer, Abraham A.; de Wit, Harriet

    2014-01-01

    Rationale A rich literature suggests that both impulsiveness and drug-induced euphoria are risk factors for drug abuse. However, few studies have examined whether sensitivity to the euphoric effects of stimulants is related to attention lapses, a behavioral measure of inattention sometimes associated with impulsivity. Objective The aim of the study was to examine ratings of d-amphetamine drug liking among individuals with high, moderate, and low attention lapses. Methods Ninety-nine healthy volunteers were divided into three equal-sized groups based on their performance on a measure of lapses of attention. The groups, who exhibited low, medium, and high attention lapses (i.e., long reaction times) on a simple reaction time task, were compared on their subjective responses (i.e., ratings of liking and wanting more drug) after acute doses of d-amphetamine (0, 5, 10, and 20 mg). Results Subjects who exhibited high lapses liked 20 mg d-amphetamine less than subjects who exhibited low lapses. These subjects also tended to report smaller increases in “wanting more drug” after d-amphetamine. Conclusion The findings suggest that participants who exhibit impaired attention may be less sensitive to stimulant-induced euphoria. PMID:19936714

  16. Are attention lapses related to d-amphetamine liking?

    PubMed

    McCloskey, Michael; Palmer, Abraham A; de Wit, Harriet

    2010-02-01

    A rich literature suggests that both impulsiveness and drug-induced euphoria are risk factors for drug abuse. However, few studies have examined whether sensitivity to the euphoric effects of stimulants is related to attention lapses, a behavioral measure of inattention sometimes associated with impulsivity. The aim of the study was to examine ratings of d-amphetamine drug liking among individuals with high, moderate, and low attention lapses. Ninety-nine healthy volunteers were divided into three equal-sized groups based on their performance on a measure of lapses of attention. The groups, who exhibited low, medium, and high attention lapses (i.e., long reaction times) on a simple reaction time task, were compared on their subjective responses (i.e., ratings of liking and wanting more drug) after acute doses of d-amphetamine (0, 5, 10, and 20 mg). Subjects who exhibited high lapses liked 20 mg d-amphetamine less than subjects who exhibited low lapses. These subjects also tended to report smaller increases in "wanting more drug" after d-amphetamine. The findings suggest that participants who exhibit impaired attention may be less sensitive to stimulant-induced euphoria.

  17. Tropospheric Lapse Rate and Methane on Titan

    NASA Technical Reports Server (NTRS)

    McKay, C. P.; Martin, S. Chau; Griffith, C. A.; Keller, R. M.; Cuzzi, Jeffery N. (Technical Monitor)

    1995-01-01

    We have reanalyzed the Voyager radio occultation data for Titan with two alternative approaches to methane condensation. In one approach, methane condensation is enhanced by the presence of nitrogen. In the other approach, methane condensation does not occur. As pointed out by Thompson, nitrogen lowers the condensation level for a methane/nitrogen Mixture and we find that the upper limit on surface relative humidity of methane obtained from the Voyager occultation data is lowered from 0.7 to 0.6. However, 140% supersaturation of methane in the troposphere, suggested by Courtin et al., allows all surface humidities to be consistent with the Voyager occultation data and the upper limit is set by other considerations. We conclude that if supersaturation is not included then the surface relative humidity of methane is between 0.08 and 0.6, with values close to 0.6 indicated. If supersaturation is included then the surface relative humidity of methane is between 0.08 and 0.85, again, with values close to 0.6 indicated. The tropospheric lapse rate on Titan appears to be determined by radiative equilibrium. It is everywhere stable against dry convection but is unstable to moist convection. This is consistent with a supersaturated atmosphere in which condensation - and hence moist convection - is inhibited. The absence of dry convection in the troposphere of Titan can be explained by a simple grey model which shows that the radiative profile of any gas for which the ratio of the gas constant to the specific heat at constant pressure is greater than 0.25 never becomes unstable to dry convection.

  18. Tropospheric Lapse Rate and Methane on Titan

    NASA Technical Reports Server (NTRS)

    McKay, C. P.; Martin, S. Chau; Griffith, C. A.; Keller, R. M.; Cuzzi, Jeffery N. (Technical Monitor)

    1995-01-01

    We have reanalyzed the Voyager radio occultation data for Titan with two alternative approaches to methane condensation. In one approach, methane condensation is enhanced by the presence of nitrogen. In the other approach, methane condensation does not occur. As pointed out by Thompson, nitrogen lowers the condensation level for a methane/nitrogen Mixture and we find that the upper limit on surface relative humidity of methane obtained from the Voyager occultation data is lowered from 0.7 to 0.6. However, 140% supersaturation of methane in the troposphere, suggested by Courtin et al., allows all surface humidities to be consistent with the Voyager occultation data and the upper limit is set by other considerations. We conclude that if supersaturation is not included then the surface relative humidity of methane is between 0.08 and 0.6, with values close to 0.6 indicated. If supersaturation is included then the surface relative humidity of methane is between 0.08 and 0.85, again, with values close to 0.6 indicated. The tropospheric lapse rate on Titan appears to be determined by radiative equilibrium. It is everywhere stable against dry convection but is unstable to moist convection. This is consistent with a supersaturated atmosphere in which condensation - and hence moist convection - is inhibited. The absence of dry convection in the troposphere of Titan can be explained by a simple grey model which shows that the radiative profile of any gas for which the ratio of the gas constant to the specific heat at constant pressure is greater than 0.25 never becomes unstable to dry convection.

  19. Chromatin Imaging with Time-Lapse Atomic Force Microscopy

    PubMed Central

    Lyubchenko, Yuri L.; Shlyakhtenko, Luda S.

    2016-01-01

    Time-lapse atomic force microscopy (AFM) is widely used for direct visualization of the nanoscale dynamics of various biological systems. The advent of high-speed AFM instrumentation made it possible to image the dynamics of proteins and protein-DNA complexes within millisecond time range. This chapter describes protocols for studies of structure and dynamics of nucleosomes with time-lapse AFM including the high-speed AFM instrument. The necessary specifics for the preparation of chromatin samples for imaging with AFM including the protocols for the surface preparation are provided. PMID:25827873

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

    NASA Technical Reports Server (NTRS)

    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.

  1. Opioid abstinence reinforcement delays heroin lapse during buprenorphine dose tapering.

    PubMed

    Greenwald, Mark K

    2008-01-01

    A positive reinforcement contingency increased opioid abstinence during outpatient dose tapering (4, 2, then 0 mg/day during Weeks 1 through 3) in non-treatment-seeking heroin-dependent volunteers who had been maintained on buprenorphine (8 mg/day) during an inpatient research protocol. The control group (n=12) received $4.00 for completing assessments at each thrice-weekly visit during dose tapering; 10 of 12 lapsed to heroin use 1 day after discharge. The abstinence reinforcement group (n=10) received $30.00 for each consecutive opioid-free urine sample; this significantly delayed heroin lapse (median, 15 days).

  2. 26 CFR 25.2704-1 - Lapse of certain rights.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... and members of the holder's family immediately before and after the lapse. The amount of the transfer... § 25.2701-2(b)(5). (ii) Member of the family. Member of the family has the meaning given it in § 25... interest in the entity, including by reason of aggregate voting power, whether or not its exercise...

  3. Time-lapse microscopy using smartphone with augmented reality markers.

    PubMed

    Baek, Dongyoub; Cho, Sungmin; Yun, Kyungwon; Youn, Keehong; Bang, Hyunwoo

    2014-04-01

    A prototype system that replaces the conventional time-lapse imaging in microscopic inspection for use with smartphones is presented. Existing time-lapse imaging requires a video data feed between a microscope and a computer that varies depending on the type of image grabber. Even with proper hardware setups, a series of tedious and repetitive tasks is still required to relocate to the region-of-interest (ROI) of the specimens. In order to simplify the system and improve the efficiency of time-lapse imaging tasks, a smartphone-based platform utilizing microscopic augmented reality (μ-AR) markers is proposed. To evaluate the feasibility and efficiency of the proposed system, a user test was designed and performed, measuring the elapse time for a trial of the task starting from the execution of the application software to the completion of restoring and imaging of an ROI saved in advance. The results of the user test showed that the average elapse time was 65.3 ± 15.2 s with 6.86 ± 3.61 μm of position error and 0.08 ± 0.40 degrees of angle error. This indicates that the time-lapse imaging task was accomplished rapidly with a high level of accuracy. Thus, simplification of both the system and the task was achieved via our proposed system.

  4. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e103580 - iss042e104044). Shows night time Earth views. Solar Array Wing (SAW) and Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  5. 30 CFR 556.55 - Lapse of bond.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Lapse of bond. 556.55 Section 556.55 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE LEASING OF SULPHUR OR OIL... 72 hours of learning of such an action. All bonds must require the surety to provide this...

  6. 30 CFR 556.55 - Lapse of bond.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Lapse of bond. 556.55 Section 556.55 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE LEASING OF SULPHUR OR OIL... 72 hours of learning of such an action. All bonds must require the surety to provide this...

  7. 30 CFR 556.55 - Lapse of bond.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Lapse of bond. 556.55 Section 556.55 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE LEASING OF SULPHUR OR OIL... 72 hours of learning of such an action. All bonds must require the surety to provide this...

  8. Negative Affect and Smoking Lapses: A Prospective Analysis

    ERIC Educational Resources Information Center

    Shiffman, Saul; Waters, Andrew J.

    2004-01-01

    Relapse is a central problem in smoking treatment. Data collected at the time of relapse episodes indicate that stress and negative affect (NA) promote relapse, but retrospective data are potentially biased. The authors performed a prospective analysis of stress and NA prior to initial lapses in smokers (N = 215). Day-to-day changes in stress…

  9. The nuclear debate: Deterrence and the lapse of faith

    SciTech Connect

    Tucker, R.W.

    1985-01-01

    This essay examines the growth of skepticism about the present system of nuclear deterrence. Tucker resists predicting the ultimate outcome, but he views the nuclear debate of this decade as an important ''lapse of faith'' in deterrence and he doubts there will ever be a full restoration of confidence.

  10. 26 CFR 25.2704-1 - Lapse of certain rights.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... immediately after death would have been $90X if the voting rights had been nonlapsing. The decrease in value... after the lapse of the voting rights. Example 2. Prior to D's death, D owned all the preferred stock of... market value of D's stock (determined immediately after D's death as though the voting rights had...

  11. 26 CFR 25.2704-1 - Lapse of certain rights.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... immediately after death would have been $90X if the voting rights had been nonlapsing. The decrease in value... after the lapse of the voting rights. Example 2. Prior to D's death, D owned all the preferred stock of... market value of D's stock (determined immediately after D's death as though the voting rights had...

  12. 26 CFR 25.2704-1 - Lapse of certain rights.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... immediately after death would have been $90X if the voting rights had been nonlapsing. The decrease in value... after the lapse of the voting rights. Example 2. Prior to D's death, D owned all the preferred stock of... market value of D's stock (determined immediately after D's death as though the voting rights had...

  13. 26 CFR 25.2704-1 - Lapse of certain rights.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... immediately after death would have been $90X if the voting rights had been nonlapsing. The decrease in value... after the lapse of the voting rights. Example 2. Prior to D's death, D owned all the preferred stock of... market value of D's stock (determined immediately after D's death as though the voting rights had...

  14. Use of nicotine replacement after a smoking lapse.

    PubMed

    Hughes, John R

    2012-06-01

    Current labeling for nicotine replacement therapy (NRT) in the United States and many countries discourages continued use of NRT after a lapse; however, recent studies and consensus statements conclude that continuing NRT postlapse substantially increases long-term abstinence. What percent of clinicians recommend continuation of NRT upon a lapse and what percent of NRT users continue NRT postlapse are unclear. The author queried 24 treatment smoking cessation programs or providers, treatment protocols, directors of quitlines and state programs, published treatment texts, and self-help manuals, books, and Internet sites. The author also recruited 101 current smokers who had attempted to stop smoking in the last 3 months and lapsed while using NRT to complete a survey via an E-mail invitation to an Internet consumer database (www.zoomerang.com). Most programs and providers (67%) did not discuss use of NRT postlapse, and only 8% recommended continuing NRT postlapse. Among recent quitters using NRT, about one fourth (27%) stopped NRT on the day of the lapse, and one fourth (25%) used NRT for only 1 or 2 days postlapse. Most (73%) reported that use of NRT postlapse was helpful. In summary, advice to use NRT postlapse and actual use of NRT for several days postlapse are uncommon.

  15. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e218184 - iss042e219070 ). Shows night time views over Egypt, Sinai, Saudi Arabia, Jordan and Israel. Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  16. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection. (still photos iss042e095641-iss042e095959 and iss042e099139-iss042e099413) Shows exterior view of the Cupola module windows as they are being opened and closed.

  17. ISS Expedition 42 Time Lapse Video of Earth

    NASA Image and Video Library

    2015-05-18

    This time lapse video taken during ISS Expedition 42 is assembled from JSC still photo collection (still photos iss042e196791 - iss042e197504). Shows Earth views. Day time views turn into night time views. Space Station Remote Manipulator System (SSRMS) or Canadarm in foreground.

  18. Lessons from NAEYC Accreditation: Avoiding Lapses in Supervision that Place Children at Risk

    ERIC Educational Resources Information Center

    Young Children, 2010

    2010-01-01

    Lapses in supervision of children can happen in all types of programs, and even a momentary lapse can have disastrous consequences. When a lapse occurs that affects program quality and puts children at risk, it is critical to consider the nature of the incident and its lessons for future risk management. Between September 2006 and September 2009,…

  19. Comparison of radiative-convective models with constant and pressure-dependent lapse rates

    NASA Technical Reports Server (NTRS)

    Hummel, J. R.; Kuhn, W. R.

    1981-01-01

    One of the most commonly used models for studying climatic processes is the convective adjustment radiation model. In current radiation models, stable temperature profiles are maintained with a convective adjustment in which the temperature lapse rate is set equal to a critical lapse rate whenever the computed lapse rates exceed the critical value. First introduced by Manabe and Strickler (1964), a variety of convective adjustment models are now in use. It is pointed out that on a global scale, moist adiabatic processes, and thus moist adiabatic lapse rates, approximate the atmospheric temperature profile. Comparisons of profiles from a one-dimensional-radiative-convective model have been made using the conventional 6.5 K/km as the critical lapse rate and the pressure-dependent moist adiabatic lapse rates. For a clear sky and a single effective cloud the surface temperatures are 1 to 3 K higher with the constant 6.5 K/km critical lapse rate.

  20. Relapse dynamics during smoking cessation: Recurrent abstinence violation effects and lapse-relapse progression

    PubMed Central

    Kirchner, Thomas R.; Shiffman, Saul; Wileyto, E. Paul

    2012-01-01

    Smoking cessation is a process that unfolds over time and is characterized by intermittent lapses. Behavioral relapse prevention interventions commonly assume that lapse-relapse progression is driven by a set of psychological responses known as the Abstinence Violation Effect (AVE; Marlatt & Gordon, 1985), yet efforts to reduce the AVE have generally failed to affect clinical outcomes. We used parametric recurrent event survival analyses to better understand the dynamic relationship between a set of AVE responses to lapsing and subsequent lapse-relapse progression. Participants were 203 smokers who achieved abstinence and subsequently lapsed on one or more separate occasions. Using electronic diaries for ecological momentary assessment, participants responded to items assessing three core components of the AVE (internal attribution of self-blame for the lapse, abstinence self-efficacy and guilt) following a total of 1,001 smoking episodes in near real time. Contrary to hypothesis, neither self-blame, self-efficacy nor guilt following participants’ first lapse predicted relapse, and all three were overshadowed by responses to recurrent lapses that followed. Controlling for responses to their first lapse, responses to each additional lapse did prospectively predict lapse progression, such that drops in self-efficacy were associated with accelerated progression to a subsequent lapse (HR=1.09, CI=1.02–1.15), while increases in internal attributions of blame actually protected against lapsing (HR=0.98, CI=0.97–0.99). Treatment with nicotine patches slowed recurrent lapse progression (HR=0.58, CI=0.48–0.70), but this effect dissipated over multiple lapses, and was moderated by elevated ratings of post-lapse guilt (HR=1.08, CI=1.01–1.18), which predicted accelerated progression within the active patch group, while protecting against lapse in the placebo group. Results highlight the dynamic nature of lapse responses during smoking cessation, indicating that self

  1. Time lapse confocal microscopy of mitochondrial movements in ascidian embryos

    NASA Astrophysics Data System (ADS)

    Sardet, C.; Rouvière, C.; Flannery, B.; Davoust, J.

    1991-05-01

    We have analysed the complex movements of vitally stained mitochondria in living eggs of the ascidian (prochordate) embryo soon after fertilization by time lapse confocal (Laser scanning) Microscopy. Our studies clearly show that it is possible to understand how the subcortical mitochondria rich layer contracts, tears and folds to reach its final location in the future posterior pole of the embryo that gives rise to the muscle cell lineage.

  2. Time-lapse Raman imaging of osteoblast differentiation

    NASA Astrophysics Data System (ADS)

    Hashimoto, Aya; Yamaguchi, Yoshinori; Chiu, Liang-Da; Morimoto, Chiaki; Fujita, Katsumasa; Takedachi, Masahide; Kawata, Satoshi; Murakami, Shinya; Tamiya, Eiichi

    2015-07-01

    Osteoblastic mineralization occurs during the early stages of bone formation. During this mineralization, hydroxyapatite (HA), a major component of bone, is synthesized, generating hard tissue. Many of the mechanisms driving biomineralization remain unclear because the traditional biochemical assays used to investigate them are destructive techniques incompatible with viable cells. To determine the temporal changes in mineralization-related biomolecules at mineralization spots, we performed time-lapse Raman imaging of mouse osteoblasts at a subcellular resolution throughout the mineralization process. Raman imaging enabled us to analyze the dynamics of the related biomolecules at mineralization spots throughout the entire process of mineralization. Here, we stimulated KUSA-A1 cells to differentiate into osteoblasts and conducted time-lapse Raman imaging on them every 4 hours for 24 hours, beginning 5 days after the stimulation. The HA and cytochrome c Raman bands were used as markers for osteoblastic mineralization and apoptosis. From the Raman images successfully acquired throughout the mineralization process, we found that β-carotene acts as a biomarker that indicates the initiation of osteoblastic mineralization. A fluctuation of cytochrome c concentration, which indicates cell apoptosis, was also observed during mineralization. We expect time-lapse Raman imaging to help us to further elucidate osteoblastic mineralization mechanisms that have previously been unobservable.

  3. The Attention-Lapse and Motor Decoupling accounts of SART performance are not mutually exclusive.

    PubMed

    Seli, Paul

    2016-04-01

    There is an ongoing debate about the mechanisms purported to underlie performance in the Sustained-Attention-to-Response Task (SART). Whereas the Attention-Lapse account posits that SART errors result from attentional disengagement, the Motor Decoupling account proposes that SART errors result from failures to inhibit a fast, prepotent motor response, despite adequate attention to the task. That SART performance might be fully accounted for by motor decoupling is problematic for a Attention-Lapse account, and for the use of the SART as an index of attention lapses. To test whether SART performance is in fact fully accounted for by motor decoupling, I examined the relation between SART performance and attention lapses while controlling for motor decoupling. The results were clear: The SART was associated with attention lapses independently of motor decoupling. Thus, the present study suggests that both accounts are correct and that the SART is a valid measure of attention lapses.

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

    PubMed

    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.

  5. Time-lapse microscopy of lung endothelial cells under hypoxia

    NASA Astrophysics Data System (ADS)

    Mehrvar, Shima; Ghanian, Zahra; Kondouri, Ganesh; Camara, Amadou S.; Ranji, Mahsa

    2017-02-01

    Objective: This study utilizes fluorescence microscopy to assess the effect of the oxygen tension on the production of reactive oxygen species (ROS) in mitochondria of fetal pulmonary artery endothelial cells (FPAECs). Introduction: Hypoxia is a severe oxygen stress, which mostly causes irreversible injury in lung cells. However, in some studies, it is reported that hypoxia decreases the severity of injuries. In this study, ROS production level was examined in hypoxic FPAECs treated with pentachlorophenol (PCP, uncoupler). This work was accomplished by monitoring and quantifying the changes in the level of the produced ROS in hypoxic cells before and after PCP treatment. Materials and methods: The dynamic of the mitochondrial ROS production in two groups of FPAECs was measured over time using time-lapse microscopy. For the first group, cells were incubated in 3% hypoxic condition for 2 hours and then continuously were exposed to hypoxic condition for imaging as well. For the second group, cells were incubated in normal oxygen condition. Time lapse images of the cells loaded with Mito-SOX (ROS indicator) were acquired, and the red fluorescence intensity profile of the cells was calculated. Changes in the level of the fluorescence intensity profile while they are treated with PCP indicates the dynamics of the ROS level. Results: The intensity profiles of the PCP-treated cells in the first group showed 47% lower ROS production rate than the PCP-treated cells in the second group. Conclusion: Time lapse microscopy revealed that hypoxic cells have lower ROS generation while treated with PCP. Therefore, this result suggests that hypoxia decreased electron transport chain activity in uncoupled chain.

  6. Identification of biogeochemical hot spots using time-lapse hydrogeophysics

    NASA Astrophysics Data System (ADS)

    Franz, T. E.; Loecke, T.; Burgin, A.

    2016-12-01

    The identification and monitoring of biogeochemical hot spots and hot moments is difficult using point based sampling techniques and sensors. Without proper monitoring and accounting of water, energy, and trace gas fluxes it is difficult to assess the environmental footprint of land management practices. One key limitation is optimal placement of sensors/chambers that adequately capture the point scale fluxes and thus a reasonable integration to landscape scale flux. In this work we present time-lapse hydrogeophysical imaging at an old agricultural field converted into a wetland mitigation bank near Dayton, Ohio. While the wetland was previously instrumented with a network of soil sensors and surface chambers to capture a suite of state variables and fluxes, we hypothesize that time-lapse hydrogeophysical imaging is an underutilized and critical reconnaissance tool for effective network design and landscape scaling. Here we combine the time-lapse hydrogeophysical imagery with the multivariate statistical technique of Empirical Orthogonal Functions (EOF) in order to isolate the spatial and temporal components of the imagery. Comparisons of soil core information (e.g. soil texture, soil carbon) from around the study site and organized within like spatial zones reveal statistically different mean values of soil properties. Moreover, the like spatial zones can be used to identify a finite number of future sampling locations, evaluation of the placement of existing sensors/chambers, upscale/downscale observations, all of which are desirable techniques for commercial use in precision agriculture. Finally, we note that combining the EOF analysis with continuous monitoring from point sensors or remote sensing products may provide a robust statistical framework for scaling observations through time as well as provide appropriate datasets for use in landscape biogeochemical models.

  7. Improved site contamination through time-lapse complex resistivity imaging

    NASA Astrophysics Data System (ADS)

    Flores Orozco, Adrian; Kemna, Andreas; Cassiani, Giorgio; Binley, Andrew

    2016-04-01

    In the framework of the EU FP7 project ModelPROBE, time-lapse complex resistivity (CR) measurements were conducted at a test site close to Trecate (NW Italy). The objective was to investigate the capabilities of the CR imaging method to delineate the geometry and dynamics of subsurface hydrocarbon contaminant plume which resulted from a crude oil spill in 1994. To achieve this it is required to discriminate the electrical signal associated to static (i.e., lithology) from dynamic changes in the subsurface, with the latter associated to significant seasonal groundwater fluctuations. Previous studies have demonstrated the benefits of the CR method to gain information which is not accessible with common electrical resistivity tomography. However field applications are still rarely and neither the analysis of the data error for CR time-lapse measurements, nor the inversion itself haven not received enough attention. While the ultimate objective at the site is to characterize, here we address the discrimination of the lithological and hydrological controls on the IP response by considering data collected in an uncontaminated area of the site. In this study we demonstrate that an adequate error description of CR measurements provides images free of artifacts and quantitative superior than previous approaches. Based on this approach, differential images computed for time-lapse data exhibited anomalies well correlated with spatiotemporal changes correlated to seasonal fluctuations in the groundwater level. The proposed analysis may be useful in the characterization of fate and transport of hydrocarbon contaminants relevant for the site, which presents areas contaminated with crude oil.

  8. Individual and Combined Effects of Multiple High-Risk Triggers on Postcessation Smoking Urge and Lapse

    PubMed Central

    2014-01-01

    Introduction: Negative affect, alcohol consumption, and presence of others smoking have consistently been implicated as risk factors for smoking lapse and relapse. What is not known, however, is how these factors work together to affect smoking outcomes. This paper uses ecological momentary assessment (EMA) collected during the first 7 days of a smoking cessation attempt to test the individual and combined effects of high-risk triggers on smoking urge and lapse. Methods: Participants were 300 female smokers who enrolled in a study that tested an individually tailored smoking cessation treatment. Participants completed EMA, which recorded negative affect, alcohol consumption, presence of others smoking, smoking urge, and smoking lapse, for 7 days starting on their quit date. Results: Alcohol consumption, presence of others smoking, and negative affect were, independently and in combination, associated with increase in smoking urge and lapse. The results also found that the relationship between presence of others smoking and lapse and the relationship between negative affect and lapse were moderated by smoking urge. Conclusions: The current study found significant individual effects of alcohol consumption, presence of other smoking, and negative affect on smoking urge and lapse. Combing the triggers increased smoking urge and the risk for lapse to varying degrees, and the presence of all 3 triggers resulted in the highest urge and lapse risk. PMID:24323569

  9. Stimulant Treatment Reduces Lapses in Attention among Children with ADHD

    PubMed Central

    Spencer, Sarah V.; Hawk, Larry W.; Richards, Jerry B.; Shiels, Keri; Pelham, William E.; Waxmonsky, James G.

    2009-01-01

    Recent research has suggested that intra-individual variability in reaction time (RT) distributions of children with ADHD is characterized by a particularly large rightward skew that may reflect lapses in attention. The purpose of the study was to provide the first randomized, placebo-controlled test of the effects of the stimulant methylphenidate (MPH) on this tail and other RT distribution characteristics. Participants were 49 9- to 12-year-old children with ADHD. Children participated in a 3-day double-blind, placebo-controlled medication assessment during which they received long-acting MPH (Concerta®), with the nearest equivalents of .3 and .6 mg/kg t.i.d. immediate-release MPH. Children completed a simple two-choice speeded discrimination task on and off of medication. Mode RT and deviation from the mode were used to examine the peak and skew, respectively, of RT distributions. MPH significantly reduced the peak and skew of RT distributions. Importantly, the two medication effects were uncorrelated suggesting that MPH works to improve both the speed and variability in responding. The improvement in variability with stimulant treatment is interpreted as a reduction in lapses in attention. This, in turn, may reflect stimulant enhancement of self-regulatory processes theorized to be at the core of ADHD. PMID:19291387

  10. Predictive modeling of addiction lapses in a mobile health application.

    PubMed

    Chih, Ming-Yuan; Patton, Timothy; McTavish, Fiona M; Isham, Andrew J; Judkins-Fisher, Chris L; Atwood, Amy K; Gustafson, David H

    2014-01-01

    The chronically relapsing nature of alcoholism leads to substantial personal, family, and societal costs. Addiction-comprehensive health enhancement support system (A-CHESS) is a smartphone application that aims to reduce relapse. To offer targeted support to patients who are at risk of lapses within the coming week, a Bayesian network model to predict such events was constructed using responses on 2,934 weekly surveys (called the Weekly Check-in) from 152 alcohol-dependent individuals who recently completed residential treatment. The Weekly Check-in is a self-monitoring service, provided in A-CHESS, to track patients' recovery progress. The model showed good predictability, with the area under receiver operating characteristic curve of 0.829 in the 10-fold cross-validation and 0.912 in the external validation. The sensitivity/specificity table assists the tradeoff decisions necessary to apply the model in practice. This study moves us closer to the goal of providing lapse prediction so that patients might receive more targeted and timely support.

  11. Debye decomposition of time-lapse spectral induced polarisation data

    NASA Astrophysics Data System (ADS)

    Weigand, M.; Kemna, A.

    2016-01-01

    Spectral induced polarisation (SIP) measurements capture the low-frequency electrical properties of soils and rocks and provide a non-invasive means to access lithological, hydrogeological, and geochemical properties of the subsurface. The Debye decomposition (DD) approach is now increasingly being used to analyse SIP signatures in terms of relaxation time distributions due to its flexibility regarding the shape of the spectra. Imaging and time-lapse (monitoring) SIP measurements, capturing SIP variations in space and time, respectively, are now more and more conducted and lead to a drastic increase in the number of spectra considered, which prompts the need for robust and reliable DD tools to extract quantitative parameters from such data. We here present an implementation of the DD method for the analysis of a series of SIP data sets which are expected to only smoothly change in terms of spectral behaviour, such as encountered in many time-lapse applications where measurement geometry does not change. The routine is based on a non-linear least-squares inversion scheme with smoothness constraints on the spectral variation and in addition from one spectrum of the series to the next to deal with the inherent ill-posedness and non-uniqueness of the problem. By means of synthetic examples with typical SIP characteristics we elucidate the influence of the number and range of considered relaxation times on the inversion results. The source code of the presented routines is provided under an open source licence as a basis for further applications and developments.

  12. Predictive Modeling of Addiction Lapses in a Mobile Health Application

    PubMed Central

    Chih, Ming-Yuan; Patton, Timothy; McTavish, Fiona M.; Isham, Andrew; Judkins-Fisher, Chris L.; Atwood, Amy K.; Gustafson, David H.

    2013-01-01

    The chronically relapsing nature of alcoholism leads to substantial personal, family, and societal costs. Addiction-Comprehensive Health Enhancement Support System (A-CHESS) is a smartphone application that aims to reduce relapse. To offer targeted support to patients who are at risk of lapses within the coming week, a Bayesian network model to predict such events was constructed using responses on 2,934 weekly surveys (called the Weekly Check-in) from 152 alcohol-dependent individuals who recently completed residential treatment. The Weekly Check-in is a self-monitoring service, provided in A-CHESS, to track patients’ recovery progress. The model showed good predictability, with the area under receiver operating characteristic curve of 0.829 in the 10-fold cross-validation and 0.912 in the external validation. The sensitivity/specificity table assists the tradeoff decisions necessary to apply the model in practice. This study moves us closer to the goal of providing lapse prediction so that patients might receive more targeted and timely support. PMID:24035143

  13. Time-lapse analysis of gravitropism in Ceratodon protonemata

    NASA Technical Reports Server (NTRS)

    Young, J. C.; Sack, F. D.

    1992-01-01

    The tip cell of the protonema of the moss Ceratodon purpureus (Hedw.) Brid. is negatively gravitropic when grown in the dark on supplemented agar. Gravitropism, plastid distribution, and plastid movement were studied in living cells using time-lapse video microscopy and infrared light. A wrong-way (downward) curvature preceded upward curvature and was detected as early as 2 minutes after reorientation. Upward curvature began 30-45 minutes after reorientation to the horizontal. Cell division temporarily reversed upward curvature, but did not inhibit wrong-way curvature. Since significant amyloplast sedimentation always occurred before the start of upward curvature, it is possible that these amyloplasts function as statoliths for upward curvature. However, no significant amyloplast sedimentation occurred before wrong-way curvature. Thus, this early phase of gravitropism cannot require plastid sedimentation for gravity sensing. Most plastids moved within and between zones, and plastid zonation was highly dynamic. Plastids moved toward the apex and toward the base of the cell at rates much slower than cytoplasmic streaming. Despite the dynamic nature of plastid movement and zonation, during upward curvature the distance between sedimented plastids and the apex stayed constant. Time-lapse analysis has revealed intriguing events not readily seen previously using destructive sampling.

  14. Temperature lapse rate and methane in Titan's troposphere

    NASA Technical Reports Server (NTRS)

    McKay, C. P.; Chau Martin, S.; Griffith, C. A.; Keller, R. M.

    1997-01-01

    We have reanalyzed the Voyager radio occultation data for Titan, examining two alternative approaches to methane condensation. In one approach, methane condensation is facilitated by the presence of nitrogen because nitrogen lowers the condensation level of a methane/nitrogen mixture. The resulting enhancement in methane condensation lowers the upper limit on surface relative humidity of methane obtained from the Voyager occultation data from 0.7 to 0.6. We conclude that in this case the surface relative humidity of methane lies between 0.08 and 0.6, with values close to 0.6 indicated. In the other approach, methane is allowed to become supersaturated and reaches 1.4 times saturation in the troposphere. In this case, surface humidities up to 100% are allowed by the Voyager occultation data, and thus the upper limit must be set by other considerations. We conclude that if supersaturation is included, then the surface relative humidity of methane can be any value greater than 0.08--unless a deep ocean is present, in which case the surface relative humidity is limited to less than 0.85. Again, values close to 0.6 are indicated. Overall, the tropospheric lapse rate on Titan appears to be determined by radiative equilibrium. The lapse rate is everywhere stable against dry convection, but is unstable to moist convection. This finding is consistent with a supersaturated atmosphere in which condensation-and hence moist convection-is inhibited.

  15. Temperature lapse rate and methane in Titan's troposphere

    NASA Technical Reports Server (NTRS)

    McKay, C. P.; Chau Martin, S.; Griffith, C. A.; Keller, R. M.

    1997-01-01

    We have reanalyzed the Voyager radio occultation data for Titan, examining two alternative approaches to methane condensation. In one approach, methane condensation is facilitated by the presence of nitrogen because nitrogen lowers the condensation level of a methane/nitrogen mixture. The resulting enhancement in methane condensation lowers the upper limit on surface relative humidity of methane obtained from the Voyager occultation data from 0.7 to 0.6. We conclude that in this case the surface relative humidity of methane lies between 0.08 and 0.6, with values close to 0.6 indicated. In the other approach, methane is allowed to become supersaturated and reaches 1.4 times saturation in the troposphere. In this case, surface humidities up to 100% are allowed by the Voyager occultation data, and thus the upper limit must be set by other considerations. We conclude that if supersaturation is included, then the surface relative humidity of methane can be any value greater than 0.08--unless a deep ocean is present, in which case the surface relative humidity is limited to less than 0.85. Again, values close to 0.6 are indicated. Overall, the tropospheric lapse rate on Titan appears to be determined by radiative equilibrium. The lapse rate is everywhere stable against dry convection, but is unstable to moist convection. This finding is consistent with a supersaturated atmosphere in which condensation-and hence moist convection-is inhibited.

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

    ERIC Educational Resources Information Center

    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…

  17. Relations among Affect, Abstinence Motivation and Confidence, and Daily Smoking Lapse Risk

    PubMed Central

    Minami, Haruka; Yeh, Vivian M.; Bold, Krysten W.; Chapman, Gretchen B.; McCarthy, Danielle E.

    2016-01-01

    Aims This study tested the hypothesis that changes in momentary affect, abstinence motivation, and confidence would predict lapse risk over the next 12–24 hours using Ecological Momentary Assessment (EMA) data from smokers attempting to quit smoking. Method 103 adult, daily, treatment-seeking smokers recorded their momentary affect, motivation to quit, abstinence confidence, and smoking behaviors in near real time with multiple EMA reports per day using electronic diaries post-quit. Results Multilevel models indicated that initial levels of negative affect were associated with smoking, even after controlling for earlier smoking status, and that short-term increases in negative affect predicted lapses up to 12, but not 24, hours later. Positive affect had significant effects on subsequent abstinence confidence, but not motivation to quit. High levels of motivation appeared to reduce increases in lapse risk that occur over hours while momentary changes in confidence did not predict lapse risk over 12 hours. Conclusion Negative affect had short-lived effects on lapse risk, whereas higher levels of motivation protected against the risk of lapsing that accumulates over hours. An increase in positive affect was associated with greater confidence to quit, but such changes in confidence did not reduce short-term lapse risk, contrary to expectations. Relations observed among affect, cognitions, and lapse seem to depend critically on the timing of assessments. PMID:24955665

  18. The Development of an Aftermath of Dietary Lapses Coping Questionnaire for Weight Control

    ERIC Educational Resources Information Center

    Shimpo, Misa; Akamatsu, Rie

    2015-01-01

    Objective: This study was designed to develop the Aftermath of Dietary Lapses Coping Questionnaire (ADLCQ) for evaluating how people cope with the aftermath of dietary lapses during weight control. Method: Between June-July 2012, dieticians working in public health centres and city offices in Sizuoka, Japan, recruited 466 participants. They were…

  19. The Development of an Aftermath of Dietary Lapses Coping Questionnaire for Weight Control

    ERIC Educational Resources Information Center

    Shimpo, Misa; Akamatsu, Rie

    2015-01-01

    Objective: This study was designed to develop the Aftermath of Dietary Lapses Coping Questionnaire (ADLCQ) for evaluating how people cope with the aftermath of dietary lapses during weight control. Method: Between June-July 2012, dieticians working in public health centres and city offices in Sizuoka, Japan, recruited 466 participants. They were…

  20. Relations among affect, abstinence motivation and confidence, and daily smoking lapse risk.

    PubMed

    Minami, Haruka; Yeh, Vivian M; Bold, Krysten W; Chapman, Gretchen B; McCarthy, Danielle E

    2014-06-01

    This study tested the hypothesis that changes in momentary affect, abstinence motivation, and confidence would predict lapse risk over the next 12-24 hr using Ecological Momentary Assessment (EMA) data from smokers attempting to quit smoking. One hundred and three adult, daily, treatment-seeking smokers recorded their momentary affect, motivation to quit, abstinence confidence, and smoking behaviors in near real time with multiple EMA reports per day using electronic diaries postquit. Multilevel models indicated that initial levels of negative affect were associated with smoking, even after controlling for earlier smoking status, and that short-term increases in negative affect predicted lapses up to 12, but not 24, hr later. Positive affect had significant effects on subsequent abstinence confidence, but not motivation to quit. High levels of motivation appeared to reduce increases in lapse risk that occur over hours although momentary changes in confidence did not predict lapse risk over 12 hr. Negative affect had short-lived effects on lapse risk, whereas higher levels of motivation protected against the risk of lapsing that accumulates over hours. An increase in positive affect was associated with greater confidence to quit, but such changes in confidence did not reduce short-term lapse risk, contrary to expectations. Relations observed among affect, cognitions, and lapse seem to depend critically on the timing of assessments.

  1. Distress Tolerance Treatment for Early-Lapse Smokers: Rationale, Program Description, and Preliminary Findings

    ERIC Educational Resources Information Center

    Brown, Richard A.; Palm, Kathleen M.; Strong, David R.; Lejuez, Carl W.; Kahler, Christopher W.; Zvolensky, Michael J.; Hayes, Steven C.; Wilson, Kelly G.; Gifford, Elizabeth V.

    2008-01-01

    A significant percentage of individuals attempting smoking cessation lapse within a matter of days, and very few are able to recover to achieve long-term abstinence. This observation suggests that many smokers may have quit-attempt histories characterized exclusively by early lapses to smoking following quit attempts. Recent negative-reinforcement…

  2. 77 FR 22069 - Proposed Information Collection (Notice of Lapse-Government Life Insurance); Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    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...

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

    ERIC Educational Resources Information Center

    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…

  4. Distress Tolerance Treatment for Early-Lapse Smokers: Rationale, Program Description, and Preliminary Findings

    ERIC Educational Resources Information Center

    Brown, Richard A.; Palm, Kathleen M.; Strong, David R.; Lejuez, Carl W.; Kahler, Christopher W.; Zvolensky, Michael J.; Hayes, Steven C.; Wilson, Kelly G.; Gifford, Elizabeth V.

    2008-01-01

    A significant percentage of individuals attempting smoking cessation lapse within a matter of days, and very few are able to recover to achieve long-term abstinence. This observation suggests that many smokers may have quit-attempt histories characterized exclusively by early lapses to smoking following quit attempts. Recent negative-reinforcement…

  5. Adolescent first lapse following smoking cessation: situation characteristics, precipitants and proximal influences.

    PubMed

    Myers, Mark G; Gwaltney, Chad J; Strong, David R; Ramsey, Susan E; Brown, Richard A; Monti, Peter M; Colby, Suzanne M

    2011-12-01

    Despite increased attention to adolescent smoking cessation, little is known about adolescent relapse following a quit attempt. To address this issue, the present study was designed to provide initial information regarding the characteristics of adolescent lapses to smoking following abstinence. Included in the present study were 204 adolescent participants in four independent smoking cessation trials. For the full sample, participants averaged 15.99 (1.27) years of age; 56% were female and 78% were white. Lapse characteristics and precipitants were assessed using the Adolescent Smoking Relapse Review. Three domains of the lapse experience were assessed: lapse situation characteristics, precipitants of use in the situation, and proximal influences (i.e., potential precipitants occurring on the same day, prior to the lapse situation). Participant reports indicated that the modal lapse situation occurred in the evening while socializing with friends at home. Urges or cravings and social pressure were commonly endorsed as occurring in lapse situations. The most frequently reported proximal influence was desire for a cigarette, followed by abstinence-violation cognitions (okay to smoke occasionally, wanted to see what it would be like) and negative emotions. The findings indicate that a broad range of factors appear to influence adolescent smoking lapse and commend the value of incorporating content relevant to managing social and affective cues, strategies for inhibiting the prepotent response to ask for a cigarette, addressing cognitions regarding the difficulty of not smoking (i.e., cessation expectancies) and combating perceptions of the ability to smoke occasionally. Published by Elsevier Ltd.

  6. Adolescent First Lapse Following Smoking Cessation: Situation Characteristics, Precipitants and Proximal Influences

    PubMed Central

    Myers, Mark G.; Gwaltney, Chad J.; Strong, David R.; Ramsey, Susan E.; Brown, Richard A.; Monti, Peter M.; Colby, Suzanne M.

    2011-01-01

    Despite increased attention to adolescent smoking cessation, little is known about adolescent relapse following a quit attempt. To address this issue, the present study was designed to provide initial information regarding the characteristics of adolescent lapses to smoking following abstinence. Included in the present study were 204 adolescent participants in four independent smoking cessation trials. For the full sample, participants averaged 15.99 (1.27) years of age; 56% were female and 78% were white. Lapse characteristics and precipitants were assessed using the Adolescent Smoking Relapse Review. Three domains of the lapse experience were assessed: lapse situation characteristics, precipitants of use in the situation, and proximal influences (i.e., potential precipitants occurring on the same day, prior to the lapse situation). Participant reports indicated that the modal lapse situation occurred in the evening while socializing with friends at home. Urges or cravings and social pressure were commonly endorsed as occurring in lapse situations. The most frequently reported proximal influence was desire for a cigarette, followed by abstinence-violation cognitions (okay to smoke occasionally, wanted to see what it would be like) and negative emotions. The findings indicate that a broad range of factors appear to influence adolescent smoking lapse and commend the value of incorporating content relevant to managing social and affective cues, strategies for inhibiting the prepotent response to ask for a cigarette, addressing cognitions regarding the difficulty of not smoking (i.e., cessation expectancies) and combating perceptions of the ability to smoke occasionally. PMID:21903332

  7. Quantitative detection of fluid distribution using time-lapse seismic

    NASA Astrophysics Data System (ADS)

    Tsuneyama, Futoshi

    The quantitative evaluation of time-lapse seismic data remains a challenge due to poor match between the model predictions and the actual seismic data. Velocity anisotropy is one important reason for the mismatch. I compile experimental velocity-anisotropy data from cores to explore the empirical relationships between anisotropy parameters and general well-log information. Then, I develop a method to estimate Thomsen's anisotropy parameters ε and gamma using a regression of the data in the crossplot domain between velocity and porosity. I present an application result of the method to demonstrate the significance of the correction. Next, using the corrected velocity, I present a method of impedance decomposition into Vp, Vs, and rho using three elastic impedances derived from the seismic inversion of angle stacks. In general, the maximum stack angle of seismic data is limited to be less than 30°, which is not wide enough to obtain the stable calculation result. I discuss the effect of noise on the analysis as the most important reason that decomposition is difficult. I show an innovative method incorporating rock-physics bounds as constraints for the analysis. I apply it to an actual dataset from an offshore oil field; I demonstrate the result of analysis for sand-body detection. Based on the estimated Vp, V s, rho and shale volume from the elastic impedances, I develop a workflow to determine the saturation of formation-water, oil and gas from seismic data. First, I consider the pressure effect and the saturation scale of fluids for time-lapse seismic analysis. Second, I demonstrate a deterministic approach to computing the fluid saturation to evaluate time-lapse seismic data. In this approach, I derive the physical properties of the water-saturated sandstone reservoir. Then, by comparing the in-situ-fluid-saturated properties with the 100% formation-water-saturated reservoir properties, I determine the bulk modulus and the density of the fluid phase in the

  8. Time-lapse video sysem used to study nesting gyrfalcons

    USGS Publications Warehouse

    Booms, Travis; Fuller, Mark R.

    2003-01-01

    We used solar-powered time-lapse video photography to document nesting Gyrfalcon (Falco rusticolus) food habits in central West Greenland from May to July in 2000 and 2001. We collected 2677.25 h of videotape from three nests, representing 94, 87, and 49% of the nestling period at each nest. The video recorded 921 deliveries of 832 prey items. We placed 95% of the items into prey categories. The image quality was good but did not reveal enough detail to identify most passerines to species. We found no evidence that Gyrfalcons were negatively affected by the video system after the initial camera set-up. The video system experienced some mechanical problems but proved reliable. The system likely can be used to effectively document the food habits and nesting behavior of other birds, especially those delivering large prey to a nest or other frequently used site.

  9. Time-Lapse Fluorescence Microscopy of Budding Yeast Cells.

    PubMed

    Kumar, Arun; Mendoza, Manuel

    2016-01-01

    The discovery of green fluorescent protein (GFP) allowed visualization of a wide variety of processes within living cells. Thanks to the development of differently colored fluorophores, it is now possible to simultaneously follow distinct subcellular events at the single cell level. Here, we describe a basic method to visualize multiple events during cytokinesis by time-lapse fluorescence microscopy in the budding yeast Saccharomyces cerevisiae. In this organism, contraction of an actomyosin-based ring drives ingression of the plasma membrane at the mother-bud division site to partition the cytoplasm of the dividing cell. Simultaneous visualization of distinct cytokinesis steps in living cells, such as ring contraction and membrane ingression, will facilitate a complete understanding of the mechanisms of eukaryotic cell division.

  10. Time-lapse microscopy patent upheld in Europe.

    PubMed

    Pearce, David

    2017-02-01

    A case for revoking Stanford University's European patent 2430454 on time-lapse microscopy was set out in Reproductive BioMedicine Online by Sterckx et al. in 2014, on the grounds that the patent claimed a method of diagnosis that was excluded under a provision of the European Patent Convention. An opposition at the European Patent Office in which this ground was raised has recently concluded with a decision that the patent is not excluded from patentability under European patent law and is to be upheld. An appeal from this decision has been filed, but the possibility of the decision being overturned is, in this author's opinion, very limited. Copyright © 2016 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  11. Combined time-lapse cinematography and immuno-electron microscopy.

    PubMed

    Balfour, B M; Goscicka, T; MacKenzie, J L; Gautam, A; Tate, M; Clark, J

    1990-04-01

    A method was developed to record interactions between mobile non-adherent immunocytes by time-lapse cinematography and then to study the same cells by immuno-electron microscopy, using monoclonal antibodies against surface components. For this purpose a modified stage was designed to fit an inverted microscope. The attachment included a device to cool the culture chamber with N2 gas, a micro-injector for monoclonal antibody and immuno-gold treatment, and two pairs of washing needles to change the medium without disturbance. The technique was first employed to study the formation of aggregates around the antigen-presenting cells in cultures containing cells from hyper-immunized animals. Recently peripheral blood cells from normal subjects and patients with immune deficiency syndromes were stimulated with pokeweed mitogen, cluster formation was recorded, and the cells were processed for immuno-electron microscopy.

  12. Updated - Research Support Facility (RSF) construction time lapse

    SciTech Connect

    2010-11-16

    Haselden Construction and RNL built the 222,000 square-foot Research Support Facility (RSF) for the U.S. Department of Energy (DOE) on the National Renewable Energy Laboratory (NREL) campus. This time lapse video begins on July 23, 2009 and the last shot was taken in June 2010. The building is designed to be a model for sustainable, high-performance building design, and will provide DOE-owned work space for administrative staff who currently occupy leased space in the nearby Denver West Office Park. The engineers and scientists from NREL's Building Technology Program set the energy criteria and the energy design strategies that are making it possible for the RSF to use no more carbon-based energy than is produced by renewables. The RSF was designed by RNL. Stantec Consulting served as the project's engineering, energy modeling and sustainability consultant.

  13. Time-Lapse Geophysics for Aquifer Characterization and Remediation Monitoring

    NASA Astrophysics Data System (ADS)

    Lane, J. W.

    2003-12-01

    Time-lapse monitoring of subsurface processes is an emerging and promising area of hydrogeophysics. The use of non-invasive or minimally invasive geophysical methods to indirectly measure time-varying fluid saturation, solute concentration, and other hydraulic and geochemical conditions facilitates cost-effective aquifer characterization and remediation. The USGS Office of Ground Water, Branch of Geophysics, in cooperation with USEPA, DOD, and university researchers, has applied time-lapse geophysics for site characterization and remediation monitoring at a number of sites. This talk presents recent examples of applied research, including: (1) application of cross-borehole and surface-to-borehole radar methods to monitor vegetable-oil emulsion injections for biostimulation at a Navy site in Fridley, MN; (2) application of borehole and cross-borehole radar methods to monitor steam injections for remediation of VOCs at the former Loring Air Force Base, ME; (3) application of electrical resistivity tomography to monitor saline tracer tests at the Massachusetts Military Reservation, MA; (4) use of borehole and cross-borehole flowmeter and a discrete-zone packer system to characterize bedrock aquifer hydraulics and water quality at the University of Connecticut landfill, Storrs, CT; and (5) application of crosshole radar methods to monitor a saline tracer in fractured bedrock at the USGS Mirror Lake Site, NH. The goals of these studies are (1) to provide increasingly quantitative information about the subsurface, critical for developing models of aquifer structure, dynamics, and processes, and (2) identification of the spatial and temporal distributions of tracers, contamination, and fluids injected to enhance degradation of contaminants.

  14. Dust Storm Time Lapse Shows Opportunity's Skies Darken

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Dust Storm Time Lapse Shows Opportunity's Skies Darken

    NASA's Opportunity rover is literally seeing some of its darkest days. Both Mars Exploration Rovers have been riding out a regional dust storm for several weeks. Conditions became particularly dreary in the Meridiani Planum region where Opportunity sits, perched on the edge of 'Victoria Crater.'

    This image is a time-lapse composite where each horizon-survey image has been compressed horizontally (but not vertically) to emphasize the sky. The relative brightness and darkness of the sky from sol to sol (over a 30-sol period beginning June 14, 2007) is depicted accurately in these images, which view roughly the same part of the plains southwest of the rover. The images are approximately true color composites, generated from calibrated radiance data files using the panoramic camera's 601-nanometer, 535-nanometer and 482-nanometer filters.

    The rovers' atmospheric science team is concerned that smaller, regional dust storms could expand into a larger, globe-encircling storm. That could extend the time the sun stays obscured, challenging the capability of Opportunity's solar panels to produce enough electricity for the rover to function.

    Fortunately, as of July 19, 2007, the Opportunity site is clearing slightly. When the storm ends, atmospheric scientists hope to review data from the rovers that will help them determine what sort of dust was being lifted and distributed.

    The numbers across the top of the image report a measurement of atmospheric opacity, called by the Greek letter tau. The lower the number, the clearer the sky. Both Opportunity and Spirit have been recording higher tau measurements in July 2007 than they had seen any time previously in their three and a half years on Mars. The five sol numbers across the bottom correspond (left to right) to June 14, June 30, July 5, July 13 and July 15, 2007.

  15. Dust Storm Time Lapse Shows Opportunity's Skies Darken

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Dust Storm Time Lapse Shows Opportunity's Skies Darken

    NASA's Opportunity rover is literally seeing some of its darkest days. Both Mars Exploration Rovers have been riding out a regional dust storm for several weeks. Conditions became particularly dreary in the Meridiani Planum region where Opportunity sits, perched on the edge of 'Victoria Crater.'

    This image is a time-lapse composite where each horizon-survey image has been compressed horizontally (but not vertically) to emphasize the sky. The relative brightness and darkness of the sky from sol to sol (over a 30-sol period beginning June 14, 2007) is depicted accurately in these images, which view roughly the same part of the plains southwest of the rover. The images are approximately true color composites, generated from calibrated radiance data files using the panoramic camera's 601-nanometer, 535-nanometer and 482-nanometer filters.

    The rovers' atmospheric science team is concerned that smaller, regional dust storms could expand into a larger, globe-encircling storm. That could extend the time the sun stays obscured, challenging the capability of Opportunity's solar panels to produce enough electricity for the rover to function.

    Fortunately, as of July 19, 2007, the Opportunity site is clearing slightly. When the storm ends, atmospheric scientists hope to review data from the rovers that will help them determine what sort of dust was being lifted and distributed.

    The numbers across the top of the image report a measurement of atmospheric opacity, called by the Greek letter tau. The lower the number, the clearer the sky. Both Opportunity and Spirit have been recording higher tau measurements in July 2007 than they had seen any time previously in their three and a half years on Mars. The five sol numbers across the bottom correspond (left to right) to June 14, June 30, July 5, July 13 and July 15, 2007.

  16. Predictors of smoking lapse during a 48-hour laboratory analogue smoking cessation attempt.

    PubMed

    Muench, Christine; Juliano, Laura M

    2017-06-01

    Many individuals who attempt to quit smoking experience a smoking lapse early on in the quitting process, with most lapses resulting in a return to regular smoking. Using a novel laboratory model, this study sought to investigate baseline predictors of smoking lapse during a brief, simulated smoking quit attempt. Self-report baseline measures were completed by 81 smokers, who also smoked a cigarette in the laboratory to equate recent smoke exposure. Participants were then given brief face-to-face smoking-cessation counseling along with monetary incentives to abstain from smoking for 48 hr (i.e., $40). Participants returned to the laboratory after 24 hr and 48 hr for assessment of smoking behavior. By 48 hr, 25 participants lapsed, with rates equivalent among men and women (31% vs. 31%). Higher rates of delay discounting and a preference for menthol cigarettes significantly predicted greater odds of lapsing. Shorter time to first cigarette after waking (TTFC) was associated with greater lapse risk at trend levels. No effects were observed for demographic variables, cigarettes per day, prequit abstinence self-efficacy, or depressive symptoms. Future research examining predictors of early lapse and underlying mechanisms is needed, and laboratory analogue models offer a controlled time- and cost-effective framework in which to investigate smoking cessation processes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  17. Cross-sectional and Longitudinal Analyses of Everyday Memory Lapses in Older Adults

    PubMed Central

    McAlister, Courtney; Schmitter-Edgecombe, Maureen

    2016-01-01

    Everyday memory lapses experienced by older adults (OA) were examined using a daily-diary checklist and retrospective questionnaire. In Experiment 1, 138 younger and 138 OAs indicated the frequency of forgetting of 16 memory lapses, and whether each occurred daily during the course of a week. OAs reported more memory lapses on the questionnaire, but not the daily diary. OAs reported more frequently forgetting names and words, while younger adults had more difficulty with appointments and personal dates. Fewer memory lapses on the daily diary were related to better performance on a laboratory-memory measure for OAs. In Experiment 2, 62 OAs returned for a five-year follow-up and endorsed experiencing more memory lapses on the daily diary compared to baseline, specifically forgetting more names and words, but not the retrospective questionnaire. Daily checklist memory lapses again correlated with the laboratory-memory measure. A daily checklist may be a viable way to assess everyday memory lapses. PMID:26810777

  18. Biomarkers identified with time-lapse imaging: discovery, validation, and practical application

    PubMed Central

    Chen, Alice A.; Tan, Lei; Suraj, Vaishali; Pera, Renee Reijo; Shen, Shehua

    2014-01-01

    “Time-lapse markers,” which are defined by time-lapse imaging and correlated with clinical outcomes, may provide embryologists with new opportunities for improving embryo selection. This article provides an overview of noninvasive biomarkers defined by time-lapse imaging studies. In addition to comprehensively reviewing the discovery of each time-lapse marker, it focuses on the criteria necessary for their successful integration into clinical practice, including [1] statistical and biological significance, [2] validation through prospective clinical studies, and [3] development of reliable technology to measure and quantify the time-lapse marker. Because manual analysis of time-lapse images is labor intensive and limits the practical use of the image data in the clinic, automated image analysis software platforms may contribute substantially to improvements in embryo selection accuracy. Ultimately, time-lapse markers that are based on a foundation of basic research, validated through prospective clinical studies, and enabled by a reliable quantification technology may improve IVF success rates, encourage broader adoption of single-embryo transfer, and reduce the risks associated with multiple gestation pregnancies. PMID:23499001

  19. Methylphenidate significantly reduces lapses of attention during on-road highway driving in patients with ADHD.

    PubMed

    Verster, Joris C; Roth, Thomas

    2014-10-01

    Lapses of attention are characteristic for attention-deficit/hyperactivity disorder (ADHD) and as such may impair performance of daily activities. Data from an on-road driving study were reanalyzed to determine lapses in patients with ADHD after treatment with methylphenidate and placebo.A total of 18 adult ADHD patients performed a 100-km on-road driving test and were instructed to drive with a steady lateral position and constant speed. The SD of lateral position (SDLP), that is, the weaving of the car, lapses, and alertness, was assessed.Driving was significantly better (P = 0.006) with methylphenidate (SDLP, 18.8 cm) when compared with placebo (SDLP, 21.2 cm). Both the reduction in SDLP and the number of lapses (P = 0.003) confirm this significant improvement, which is further supported by subjective assessments of perceived driving performance. Although lapses were common in the placebo condition (11/18 patients), they were much less frequently observed (5/18 patients) after treatment with methylphenidate. Postdriving assessments suggest that lapses often go unnoticed by drivers.In conclusion, methylphenidate significantly improves driving of patients with ADHD by significantly reducing the number of lapses.

  20. Time-lapse imaging of neural development: zebrafish lead the way into the fourth dimension.

    PubMed

    Rieger, Sandra; Wang, Fang; Sagasti, Alvaro

    2011-07-01

    Time-lapse imaging is often the only way to appreciate fully the many dynamic cell movements critical to neural development. Zebrafish possess many advantages that make them the best vertebrate model organism for live imaging of dynamic development events. This review will discuss technical considerations of time-lapse imaging experiments in zebrafish, describe selected examples of imaging studies in zebrafish that revealed new features or principles of neural development, and consider the promise and challenges of future time-lapse studies of neural development in zebrafish embryos and adults.

  1. Time-lapse imaging of neural development: Zebrafish lead the way into the fourth dimension

    PubMed Central

    Rieger, Sandra; Wang, Fang; Sagasti, Alvaro

    2011-01-01

    Time-lapse imaging is often the only way to appreciate fully the many dynamic cell movements critical to neural development. Zebrafish possess many advantages that make them the best vertebrate model organism for live imaging of dynamic development events. This review will discuss technical considerations of time-lapse imaging experiments in zebrafish, describe selected examples of imaging studies in zebrafish that revealed new features or principles of neural development, and consider the promise and challenges of future time-lapse studies of neural development in zebrafish embryos and adults. PMID:21305690

  2. Observation of infiltration experiments with time lapse electrical resistivity tomography

    NASA Astrophysics Data System (ADS)

    Noell, Ursula; Ganz, Christina; Altfelder, Sven; Günther, Thomas; Duijnisveld, Wilhelmus; Grissemann, Christoph

    2010-05-01

    Recent progress in the development of resistivity equipment enables the real time observation of infiltration processes through the vadose zone. In order to study the advantages and limitations of the method infiltration experiments are carried out for different soil types at various locations. All sites are subsequently excavated and investigated in detail. For an improved verification of the resistivity data the most recent experiment is conducted using a colour tracer. Two infiltration experiments are carried out in sandy soil. The location is Fuhrberg, close to Hannover, Germany. The area has been intensively studied for soil research purposes for more than 30 years. During both infiltration experiments water (110 l/80 l) is infiltrated for a period of 4.5 h and 8 h, respectively, and the infiltration process is observed by ERT. The resistivity measurements are conducted using a 3D-dipole-dipole configuration with electrode distances of 20 cm in the centre of the infiltration field. The whole resistivity array consists of 200 and 300 electrodes, respectively. The second experiment uses increased electrode spacing in the border area in order to enable the resolution of the deeper groundwater table (3.5 m during the second experiment compared to about 1.2 m for the first experiment). Immediately after completion of the resistivity measurements TDR and tensiometer measurements are carried out in 5-8 slices of the excavated infiltration area over a period of several days. The colour tracer used during the second experiment clearly outlines the infiltration plume with sharp outer limits. The ERT inversion depicts the shape of the plume successfully. Time lapse ERT interpretation reveals the development of the plume in time. The combination of ERT interpretation and TDR measurements enables the construction of the relationship between water content and resistivity as reconstructed by ERT using an Archie approach. By using this function water content changes can be

  3. Near-surface air temperature lapse rates in Xinjiang, northwestern China

    NASA Astrophysics Data System (ADS)

    Du, Mingxia; Zhang, Mingjun; Wang, Shengjie; Zhu, Xiaofan; Che, Yanjun

    2017-01-01

    Lapse rates of near-surface (2 m) air temperature are important parameters in hydrologic and climate simulations, especially for the mountainous areas without enough in-situ observations. In Xinjiang, northwestern China, the elevations range from higher than 7000 m to lower than sea level, but the existing long-term meteorological measurements are limited and distributed unevenly. To calculate lapse rates in Xinjiang, the daily data of near-surface air temperature (T min, T ave, and T max) were measured by automatic weather stations from 2012 to 2014. All the in situ observation stations were gridded into a network of 1.5° (latitude) by 1.5° (longitude), and the spatial distribution and the daily, monthly, seasonal variations of lapse rates for T min, T ave, and T max in Xinjiang are analyzed. The Urumqi River Basin has been considered as a case to study the influence of elevation, aspect, and the wet and dry air conditions to the T min, T ave, and T max lapse rates. Results show that (1) the lapse rates for T min, T ave, and T max vary spatially during the observation period. The spatial diversity of T min lapse rates is larger than that of T ave, and that of T max is the smallest. For each season, T max lapse rates have more negative values than T ave lapse rates which are steeper than T min lapse rates. The weakest spatial diversity usually appears in July throughout a year. (2) The comparison for the three subregions (North, Middle, and South region) exhibits that lapse rates have similar day-to-day and month-to-month characteristics which present shallower values in winter months and steeper values in summer months. The T ave lapse rates in North region are shallower than those in Middle and South region, and the steepest T ave lapse rates of the three regions all appear in April. T min lapse rates are shallower than T max lapse rates. The maximum medians of T min and T max lapse rates for each grid in the three regions all appear in January, whereas the

  4. Nanoscale Nucleosome Dynamics Assessed with Time-lapse AFM

    PubMed Central

    Lyubchenko, Yuri L.

    2013-01-01

    A fundamental challenge associated with chromosomal gene regulation is accessibility of DNA within nucleosomes. Recent studies performed by various techniques, including single-molecule approaches, led to the realization that nucleosomes are dynamic structures rather than static systems, as it was once believed. Direct data is required in order to understand the dynamics of nucleosomes more clearly and answer fundamental questions, including: What is the range of nucleosome dynamics? Does a non-ATP dependent unwrapping process of nucleosomes exist? What are the factors facilitating the large scale opening and unwrapping of nucleosomes? This review summarizes the results of nucleosome dynamics obtained with time-lapse AFM, including a high-speed version (HS-AFM) capable of visualizing molecular dynamics on the millisecond time scale. With HS-AFM, the dynamics of nucleosomes at a sub-second time scale was observed allowing one to visualize various pathways of nucleosome dynamics, such as sliding and unwrapping, including complete dissociation. Overall, these findings reveal new insights into the dynamics of nucleosomes and the novel mechanisms controlling spontaneous chromatin dynamics. PMID:24839467

  5. Time-lapse microscopy of macrophages during embryonic vascular development.

    PubMed

    Al-Roubaie, Sarah; Hughes, Jasmine H; Filla, Michael B; Lansford, Rusty; Lehoux, Stephanie; Jones, Elizabeth A V

    2012-09-01

    Macrophages are present before the onset of blood flow, but very little is known about their function in vascular development. We have developed a technique to concurrently label both endothelial cells and macrophages for time-lapse microscopy using co-injection of fluorescently conjugated acetylated low-density lipoprotein (AcLDL) and phagocytic dye PKH26-PCL. We characterize double-labeled cells to confirm specific labeling of macrophages. Double-labeled cells circulate, roll along the endothelium, and extravasate from vessels. Most observed macrophages are integrated into the vessel wall, showing an endothelial-like morphology. We used transgenic quail that express a fluorescent protein driven by the endothelial-specific promoter Tie1 in conjugation with the phagocytic dye to analyze these cells. Circulating PKH26-PCL-labeled cells are mostly Tie1-, but those which have integrated into the vessel wall are largely Tie1+. The endothelial-like phagocytic cells were generally stationary during normal vascular development. We, therefore, induced vascular remodeling and found that these cells could be recruited to sites of remodeling. The active interaction of endothelial cells and macrophages support the hypothesis that these cells are involved in vascular remodeling. The presence of phagocytic endothelial-like cells suggests either a myeloid-origin to certain endothelial cells or that circulating endothelial cells/hematopoietic stem cells have phagocytic capacity. Copyright © 2012 Wiley Periodicals, Inc.

  6. Towards a LAPSE Theory of Teacher Preparation in English as a Second Language

    ERIC Educational Resources Information Center

    Alatis, James E.

    1974-01-01

    'LAPSE' is an organising acronym for the kinds of courses that should be included in any teacher education programme in English for speakers of other languages. The letters stand for Linguistics, Anthropology, Psychology, Sociolinguistics, English (and Education). (Author)

  7. NASA HS3 Mission Time Lapse Highlights Cameras Over Tropical Systems

    NASA Image and Video Library

    This is a time-lapse video created with images recorded during a recent HS3 Science Missions with the NASA Global Hawk. Shown are the images from the Daylight, HDVis, and the Low-light Cameras on t...

  8. Time-Lapse of Backplane of the JWST Being Moved Into Clean Room

    NASA Image and Video Library

    This is a time-lapse video of the center section of the 'pathfinder' backplane for NASA's James Webb Space Telescope being moved into the clean room at NASA's Goddard Space Flight Center in Greenbe...

  9. Distress tolerance treatment for early-lapse smokers: rationale, program description, and preliminary findings.

    PubMed

    Brown, Richard A; Palm, Kathleen M; Strong, David R; Lejuez, Carl W; Kahler, Christopher W; Zvolensky, Michael J; Hayes, Steven C; Wilson, Kelly G; Gifford, Elizabeth V

    2008-05-01

    A significant percentage of individuals attempting smoking cessation lapse within a matter of days, and very few are able to recover to achieve long-term abstinence. This observation suggests that many smokers may have quit-attempt histories characterized exclusively by early lapses to smoking following quit attempts. Recent negative-reinforcement conceptualizations of early lapse to smoking suggest that individuals' reactions to withdrawal and inability to tolerate the experience of these symptoms, rather than withdrawal severity itself, may represent an important treatment target in the development of new behavioral interventions for this subpopulation of smokers. This article presents the theoretical rationale and describes a novel, multicomponent distress-tolerance treatment for early-lapse smokers that incorporates behavioral and pharmacological elements of standard smoking-cessation treatment, whereas drawing distress-tolerance elements from exposure-based and Acceptance and Commitment Therapy-based treatment approaches. Preliminary data from a pilot study (N = 16) are presented, and clinical implications are discussed.

  10. Orb-2's Antares Rolls Out to Launch Pad (Time-Lapse)

    NASA Image and Video Library

    This time-lapse video shows the roll out of the Orbital Sciences Corporation Antares rocket, with the Cygnus spacecraft aboard, from the Horizontal Integration Facility to the Mid-Atlantic Regional...

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

    PubMed Central

    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

    Background 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 areHow 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? Methods 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. Results 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. Conclusions 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. PMID:27814779

  12. [Embryo selection in IVF/ICSI cycles using time-lapse microscopy and the clinical outcomes].

    PubMed

    Chen, Minghao; Huang, Jun; Zhong, Ying; Quan, Song

    2015-12-01

    To compare the clinical outcomes of embryos selected using time-lapse microscopy and traditional morphological method in IVF/ICSI cycles and evaluate the clinical value of time-lapse microscopy in early embryo monitoring and selection. e retrospectively analyzed the clinical data of 139 IVF/ICSI cycles with embryo selection based on time-lapse monitoring (TLM group, n=68) and traditional morphological method (control group, n=71). The βHCG-positive rate, clinical pregnancy rate and embryo implantation rate were compared between the 2 groups. Subgroup analysis was performed in view of female patients age and the fertilization type. The βHCG-positive rate, clinical pregnancy rate and implantation rate were 66.2%, 61.8% and 47.1% in TLM group, significantly higher than those in the control group (47.9%, 43.7% and 30.3%, respectively; P<0.05). Compared with patients below 30 years of age, patients aged between 31 and 35 years benefited more from time-lapse monitoring with improved clinical outcomes. time-lapse monitoring significantly increased the βHCG-positive rate, clinical pregnancy rate and implantation rate for patients undergoing IVF cycles, but not for those undergoing ICSI or TESA cycles. Compared with those selected using traditional morphological method, the embryos selected with time-lapse microscopy have better clinical outcomes, especially in older patients (31-35 years of age) and in IVF cycles.

  13. Estimation of atmospheric parameters from time-lapse imagery

    NASA Astrophysics Data System (ADS)

    McCrae, Jack E.; Basu, Santasri; Fiorino, Steven T.

    2016-05-01

    A time-lapse imaging experiment was conducted to estimate various atmospheric parameters for the imaging path. Atmospheric turbulence caused 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. By presuming this turbulence follows the Kolmogorov spectrum, weighting functions can be derived which relate the turbulence strength along the path to the shifts measured. 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 presume Cn2 is constant along the path, then an estimate for r0 can 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 this approach would yield a poor estimator. Instead, the weighting functions for a number of different patch sizes can be combined through the Moore-Penrose pseudo-inverse to create a new weighting function which yields the least-squares optimal linear combination of measurements for estimation of r0. This approach is carried out, and it is observed that this approach is somewhat noisy because the pseudo-inverse assigns weights much greater than one to many of the observations.

  14. Variability of the isotopic lapse rate across the mountain ranges in Wyoming

    NASA Astrophysics Data System (ADS)

    Brian, H.; Fan, M.

    2012-12-01

    Stable isotope based paleoaltimetry studies require knowledge of the isotope-elevation gradient during the time of interest, but this information is rarely available. As a result, many studies often apply the modern local lapse rate or a global average lapse rate and assume these values are valid for the area of interest and that they hold through time. However, natural variability in local-scale climate and mountain geometry and morphology can influence the isotope-elevation (and temperature-elevation) gradient. We evaluate the inter- and intra-mountain range variability of modern climate and isotope values of stream water for three Laramide ranges in Wyoming (Wind River Range, Bighorn and Laramie Mountains), as well as for a regional elevation transect across the central Rocky mountain front. Samples of steam water were taken from major catchments across Wyoming in 2007, 2011, and 2012. We find that the modern lapse rate for these ranges is -1.7‰/km, -2.2‰/km and -1.8‰/km respectively. Although these values are very similar to one another and to the global isotopic lapse rate (-2.1‰/km), large variation (up to 6‰/km) exists among individual small river catchments of the Bighorn Mountains. The variability in catchment-scale lapse rate does not appear to be systematically related to annual, or seasonal surface air temperature, precipitation amount, or catchment area. However, the range-scale lapse rates may yet reflect the regional climate, which is generally coolest and driest in the Wind River Range (lowest lapse rate) and warmest and wettest in the Bighorn Mountains (highest lapse rate). Similar d-excess values exist across individual mountain ranges, but inter-mountain range differences indicate that the Laramie Mountains (and regions of western Nebraska) receive evaporatively enriched rainwater compared to those in the Wind River Range and Bighorn Mountains. These differences do not necessarily require separate vapor sources as the lower d

  15. Time-lapse joint inversion of geophysical data with automatic joint constraints and dynamic attributes

    NASA Astrophysics Data System (ADS)

    Rittgers, J. B.; Revil, A.; Mooney, M. A.; Karaoulis, M.; Wodajo, L.; Hickey, C. J.

    2016-12-01

    Joint inversion and time-lapse inversion techniques of geophysical data are often implemented in an attempt to improve imaging of complex subsurface structures and dynamic processes by minimizing negative effects of random and uncorrelated spatial and temporal noise in the data. We focus on the structural cross-gradient (SCG) approach (enforcing recovered models to exhibit similar spatial structures) in combination with time-lapse inversion constraints applied to surface-based electrical resistivity and seismic traveltime refraction data. The combination of both techniques is justified by the underlying petrophysical models. We investigate the benefits and trade-offs of SCG and time-lapse constraints. Using a synthetic case study, we show that a combined joint time-lapse inversion approach provides an overall improvement in final recovered models. Additionally, we introduce a new approach to reweighting SCG constraints based on an iteratively updated normalized ratio of model sensitivity distributions at each time-step. We refer to the new technique as the Automatic Joint Constraints (AJC) approach. The relevance of the new joint time-lapse inversion process is demonstrated on the synthetic example. Then, these approaches are applied to real time-lapse monitoring field data collected during a quarter-scale earthen embankment induced-piping failure test. The use of time-lapse joint inversion is justified by the fact that a change of porosity drives concomitant changes in seismic velocities (through its effect on the bulk and shear moduli) and resistivities (through its influence upon the formation factor). Combined with the definition of attributes (i.e. specific characteristics) of the evolving target associated with piping, our approach allows localizing the position of the preferential flow path associated with internal erosion. This is not the case using other approaches.

  16. Acoustic startle and prepulse inhibition predict smoking lapse in posttraumatic stress disorder.

    PubMed

    Vrana, Scott R; Calhoun, Patrick S; Dennis, Michelle F; Kirby, Angela C; Beckham, Jean C

    2015-10-01

    Most smokers who attempt to quit lapse within the first week and are ultimately unsuccessful in their quit attempt. Nicotine withdrawal exacerbates cognitive and attentional problems and may be one factor in smoking relapse. The startle reflex response and prepulse inhibition (PPI) of the response are sensitive to arousal and early attentional dysregulation. The current study examined whether startle response and PPI are related to early smoking lapse, and if this differs in people with and without posttraumatic stress disorder (PTSD). Participants with (N = 34) and without (N = 57) PTSD completed a startle reflex and PPI assessment during (1) ad lib smoking (2) on the first day of abstinence during a quit attempt. Most (88%) participants lapsed within the first week of the quit attempt. PTSD status predicted shorter time to lapse. Larger startle magnitude and greater PPI predicted a longer duration before smoking lapse. When diagnostic groups were examined separately, greater PPI predicted a longer successful quit attempt only in participants with a PTSD diagnosis. The startle reflex response and PPI may provide an objective, neurophysiological evaluation of regulation of arousal and early attentional processes by nicotine, which are important factors in smoking cessation success.

  17. Developing human laboratory models of smoking lapse behavior for medication screening

    PubMed Central

    McKee, Sherry A.

    2009-01-01

    Use of human laboratory analogues of smoking behavior can provide an efficient, cost-effective mechanistic evaluation of a medication signal on smoking behavior, with the result of facilitating translational work in medications development. Although a number of human laboratory models exist to investigate various aspects of smoking behavior and nicotine dependence phenomena, none have yet modeled smoking lapse behavior. The first instance of smoking during a quit attempt (i.e. smoking lapse) is highly predictive of relapse and represents an important target for medications development. Focusing on an abstinence outcome is critical for medication screening as the US Food and Drug Administration approval for cessation medications is contingent on demonstrating effects on smoking abstinence. This paper outlines a three-stage process for the development of a smoking lapse model for the purpose of medication screening. The smoking lapse paradigm models two critical features of lapse behavior: the ability to resist the first cigarette and subsequent ad libitum smoking. Within the context of the model, smokers are first exposed to known precipitants of smoking relapse (e.g. nicotine deprivation, alcohol, stress), and then presented their preferred brand of cigarettes. Their ability to resist smoking is then modeled and once smokers ‘give in’ and decide to smoke, they participate in a tobacco self-administration session. Ongoing and completed work developing and validating these models for the purpose of medication screening is discussed. PMID:18855800

  18. THE ROLE OF NEGATIVE AFFECT IN RISK FOR EARLY LAPSE AMONG LOW DISTRESS TOLERANCE SMOKERS

    PubMed Central

    Abrantes, Ana M.; Strong, David R.; Lejuez, Carl W.; Kahler, Christopher W.; Carpenter, Linda L.; Price, Lawrence H.; Niaura, Raymond; Brown, Richard A.

    2008-01-01

    Individual differences in the ability to tolerate negative affect due to psychological and/or physical discomfort (e.g., distress tolerance) are emerging as an important predictor of smoking cessation outcomes. The purpose of this study was to build on existing evidence by exploring the relationship between levels of distress tolerance (DT) and negative affect on quit date in relation to risk for early lapse. Eighty-one smokers (48% female; M age = 42.6 years) who completed laboratory-based, behavioral distress tolerance tasks prior to an unaided quit attempt were categorized into low, average, and high persistence on the tasks. Low persistence smokers were significantly more likely to lapse on the assigned quit day. Among smokers able to achieve abstinence on quit day, low persistence smokers demonstrated higher levels of negative affect and urges compared to high persistence smokers. Further, negative affect-related risk for early lapse was strongest among those with low persistence. These findings suggest that smokers low in distress tolerance may be particularly vulnerable to very early lapse to smoking and that increases in negative affect may contribute to the risk for early lapse in this high-risk group of smokers. PMID:18684569

  19. Revealing the secret life of pre-implantation embryos by time-lapse monitoring: A review.

    PubMed

    Faramarzi, Azita; Khalili, Mohammad Ali; Micara, Giulietta; Agha-Rahimi, Azam

    2017-05-01

    High implantation success following in vitro fertilization cycles are achieved via the transfer of embryos with the highest developmental competence. Multiple pregnancies as a result of the transfer of several embryos per cycle accompany with various complication. Thus, single-embryo transfer (SET) is the preferred practice in assisted reproductive technique (ART) treatment. In order to improve the pregnancy rate for SET, embryologists need reliable biomarkers to aid their selection of embryos with the highest developmental potential. Time-lapse technology is a noninvasive alternative conventional microscopic assessment. It provides uninterrupted and continues the survey of embryo development to transfer day. Today, there are four time-lapse systems that are commercially available for ART centers. In world and Iran, the first time lapse babies were born in 2010 and 2015, respectively, conceived by SET. Here, we review the use of time-lapse monitoring in the observation of embryogenesis as well as its role in SET. Although, the findings from our review support common use of time-lapse monitoring in ART centers; but, future large studies assessing this system in well-designed trials are necessary.

  20. Developing human laboratory models of smoking lapse behavior for medication screening.

    PubMed

    McKee, Sherry A

    2009-01-01

    Use of human laboratory analogues of smoking behavior can provide an efficient, cost-effective mechanistic evaluation of a medication signal on smoking behavior, with the result of facilitating translational work in medications development. Although a number of human laboratory models exist to investigate various aspects of smoking behavior and nicotine dependence phenomena, none have yet modeled smoking lapse behavior. The first instance of smoking during a quit attempt (i.e. smoking lapse) is highly predictive of relapse and represents an important target for medications development. Focusing on an abstinence outcome is critical for medication screening as the US Food and Drug Administration approval for cessation medications is contingent on demonstrating effects on smoking abstinence. This paper outlines a three-stage process for the development of a smoking lapse model for the purpose of medication screening. The smoking lapse paradigm models two critical features of lapse behavior: the ability to resist the first cigarette and subsequent ad libitum smoking. Within the context of the model, smokers are first exposed to known precipitants of smoking relapse (e.g. nicotine deprivation, alcohol, stress), and then presented their preferred brand of cigarettes. Their ability to resist smoking is then modeled and once smokers 'give in' and decide to smoke, they participate in a tobacco self-administration session. Ongoing and completed work developing and validating these models for the purpose of medication screening is discussed.

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

    PubMed Central

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

    2016-01-01

    Background 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. Objective 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. Methods 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. Results 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 (P<.001), interaction with someone smoking (P<.001), and lower cessation motivation (P=.03) within 4 hours of the first lapse compared with EMAs collected when lapse was not imminent. Further, the total number of lapse risk factors present within 4 hours of lapse (mean 2.43, SD 1.37) was significantly higher than the number of lapse risk factors present during periods when lapse was not imminent (mean 1.35, SD 1.04), P<.001. Overall, 62% (32/52) of all participants who lapsed completed at least one EMA wherein they

  2. Global dynamics of selective attention and its lapses in primary auditory cortex.

    PubMed

    Lakatos, Peter; Barczak, Annamaria; Neymotin, Samuel A; McGinnis, Tammy; Ross, Deborah; Javitt, Daniel C; O'Connell, Monica Noelle

    2016-12-01

    Previous research demonstrated that while selectively attending to relevant aspects of the external world, the brain extracts pertinent information by aligning its neuronal oscillations to key time points of stimuli or their sampling by sensory organs. This alignment mechanism is termed oscillatory entrainment. We investigated the global, long-timescale dynamics of this mechanism in the primary auditory cortex of nonhuman primates, and hypothesized that lapses of entrainment would correspond to lapses of attention. By examining electrophysiological and behavioral measures, we observed that besides the lack of entrainment by external stimuli, attentional lapses were also characterized by high-amplitude alpha oscillations, with alpha frequency structuring of neuronal ensemble and single-unit operations. Entrainment and alpha-oscillation-dominated periods were strongly anticorrelated and fluctuated rhythmically at an ultra-slow rate. Our results indicate that these two distinct brain states represent externally versus internally oriented computational resources engaged by large-scale task-positive and task-negative functional networks.

  3. Climatological characteristics of high altitude wind shear and lapse rate layers

    NASA Technical Reports Server (NTRS)

    Ehernberger, L. J.; Guttman, N. B.

    1981-01-01

    Indications of the climatological distribution of wind shear and temperature lapse and inversion rates as observed by rawinsonde measurements over the western United States are recorded. Frequencies of the strongest shear, lapse rates, and inversion layer strengths were observed for a 1 year period of record and were tabulated for the lower troposphere, the upper troposphere, and five altitude intervals in the lower stratosphere. Selected bivariate frequencies were also tabulated. Strong wind shears, lapse rates, and inversion are observed less frequently as altitude increases from 175 millibars to 20 millibars. On a seasonal basis the frequencies were higher in winter than in summer except for minor influences due to increased tropopause altitude in summer and the stratospheric wind reversal in the spring and fall.

  4. Physical activity adoption to adherence, lapse, and dropout: a self-determination theory perspective.

    PubMed

    Kinnafick, Florence-Emilie; Thøgersen-Ntoumani, Cecilie; Duda, Joan L

    2014-05-01

    Grounded in Self-Determination Theory, we aimed to explore and identify key motivational processes involved in the transition from a physically inactive to an active lifestyle, and the processes involved in lapse and dropout behavior within a walking program. We implemented a qualitative, longitudinal case study method, using semistructured interviews and theoretical thematic analyses. Fifteen women were interviewed over 10 months and three profiles were generated: (a) nonadherence, (b) lapse/readoption of physical activity, and (c) adherence. Internalization of walking behavior was key to adherence. Satisfaction of the needs for competence and relatedness were central for participation during exercise at the adoption stages, and autonomy was particularly pertinent in facilitating adherence. Those who lapsed and restarted physical activity experienced feelings of autonomy at the point of readoption. Sources of support were driving forces in the adoption and adherence phases.

  5. Source Repeatability of Time-Lapse Offset VSP Surveys for Monitoring CO2 Injection

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Huang, L.; Rutledge, J. T.; Denli, H.; Zhang, H.; McPherson, B. J.; Grigg, R.

    2009-12-01

    Time-lapse vertical seismic profiling (VSP) surveys have the potential to remotely track the migration of injected CO2 within a geologic formation. To accurately detect small changes due to CO2 injection, the sources of time-lapse VSP surveys must be located exactly at the same positions. However, in practice, the source locations can vary from one survey to another survey. Our numerical simulations demonstrate that a variation of a few meters in the VSP source locations can result in significant changes in time-lapse seismograms. To address the source repeatability issue, we apply double-difference tomography to downgoing waves of time-lapse offset VSP data to invert for the source locations and the velocity structures simultaneously. In collaboration with Resolute Natural Resources, Navajo National Oil and Gas Company, and the Southwest Regional Partnership on Carbon Sequestration under the support of the U.S. Department of Energy’s National Energy Technology Laboratory, one baseline and two repeat offset VSP datasets were acquired in 2007-2009 for monitoring CO2 injection at the Aneth oil field in Utah. A cemented geophone string was used to acquire the data for one zero-offset and seven offset source locations. During the data acquisition, there was some uncertainty in the repeatability of the source locations relative to the baseline survey. Our double-difference tomography results of the Aneth time-lapse VSP data show that the source locations for different surveys are separated up to a few meters. Accounting for these source location variations during VSP data analysis will improve reliability of time-lapse VSP monitoring.

  6. Psychological symptoms, smoking lapse behavior, and the mediating effects of nicotine withdrawal symptoms: A laboratory study.

    PubMed

    Ameringer, Katherine J; Leventhal, Adam M

    2015-03-01

    The influence of psychological symptoms on smoking-lapse behavior is critical to understand. However, this relationship is obscured by comorbidity across multiple forms of psychological symptoms and their overlap with nicotine withdrawal. To address these challenges, we constructed a structural model of latent factors underlying 9 manifest scales of affective and behavioral symptoms and tested relations between latent factors and manifest scale residuals with nicotine withdrawal and smoking lapse in a laboratory analog task. Adult daily smokers (N = 286) completed a baseline session at which several forms of affective and behavioral symptoms were assessed and 2 experimental sessions (i.e., following 16 hr of smoking abstinence and following regular smoking), during which withdrawal symptoms and delay of smoking in exchange for monetary reinforcement, as an analogue for lapse propensity, were measured. A single second-order factor of general psychological maladjustment associated with more severe withdrawal-like symptoms, which in turn associated with shorter delay of smoking. The first-order factors, which tapped qualitatively unique domains of psychological symptoms (low positive affect, negative affect, disinhibition), and the manifest scale residuals provided little predictive power beyond the second-order factor with regard to lapse behavior. Relations among general psychological maladjustment, withdrawal-like symptoms, and lapse were significant in both abstinent and nonabstinent conditions, suggesting that psychological maladjustment, and not nicotine withdrawal per se, accounted for the relation with lapse. These results highlight the potential for smoking-cessation strategies that target general psychological maladjustment processes and have implications for addressing withdrawal-like symptoms among individuals with psychological symptoms. (c) 2015 APA, all rights reserved).

  7. Pain-related anxiety as a predictor of early lapse and relapse to cigarette smoking.

    PubMed

    LaRowe, Lisa R; Langdon, Kirsten J; Zvolensky, Michael J; Zale, Emily L; Ditre, Joseph W

    2017-08-01

    Although emerging research suggests that pain-related anxiety may play a role in the maintenance of tobacco dependence, no previous work has examined pain-related anxiety as a predictor of smoking cessation outcomes. The current study aimed to test the hypothesis that pain-related anxiety would predict early lapse and relapse to cigarette smoking. These data were collected in the context of a primary study examining the role of emotional vulnerabilities in smoking cessation. The current analyses were conducted among 55 daily cigarette smokers who attempted to quit without psychosocial or pharmacological cessation aids. Pain-related anxiety was assessed at baseline using the Pain Anxiety Symptom Scale-20 (PASS-20). Early lapse and relapse were assessed using timeline follow-back procedures. Cox regression analyses indicated that pain-related anxiety was a significant predictor of both early smoking lapse and relapse such that for every 1-point increase on the PASS-20, the risk of early lapse increased by 3.7% and the risk of early relapse increased by 3.6%. These effects were evident above and beyond the variance accounted for by tobacco dependence, past 4-week pain severity, anxiety sensitivity, and the presence of current Axis I psychopathology. Kaplan-Meier survival analyses further revealed that among early lapsers, greater pain-related anxiety predicted a more rapid trajectory to lapse. Pain-related anxiety was also a significant predictor of early lapse when the sample was limited to smokers with past 4-week pain. These findings lend empirical support to the notion that pain-related anxiety may contribute to the maintenance of tobacco dependence among smokers who experience varying levels of pain intensity. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. A prospective examination of distress tolerance and early smoking lapse in adult self-quitters

    PubMed Central

    Lejuez, C. W.; Strong, David R.; Kahler, Christopher W.; Zvolensky, Michael J.; Carpenter, Linda L.; Niaura, Raymond; Price, Lawrence H.

    2009-01-01

    Introduction: A significant percentage of smokers attempting cessation lapse to smoking within a matter of days, and current models of relapse devote insufficient attention to such early smoking lapse. Studies attempting to relate severity of nicotine withdrawal symptoms to short-term smoking cessation outcomes have yielded equivocal results. How one reacts to the discomfort of nicotine withdrawal and quitting smoking (i.e., distress tolerance) may be a more promising avenue of investigation with important treatment implications. Methods: The present investigation examined distress tolerance and early smoking lapse using a prospective design. Participants were 81 adult daily smokers recruited through newspaper advertisements targeted at smokers planning to quit smoking without assistance (i.e., no pharmacotherapy or psychosocial treatment; 42 males and 39 females; mean age = 42.6 years, SD = 12.20). Results: As hypothesized, both greater breath-holding duration and carbon dioxide–enriched air persistence were associated with a significantly lower risk of smoking lapse following an unaided quit attempt. These effects were above and beyond the risk associated with levels of nicotine dependence, education, and history of major depressive disorder, suggesting that distress tolerance and task persistence may operate independently of risk factors such as nicotine dependence and depressive history. In contrast to expectation, persistence on the Paced Auditory Serial Addition Test (a psychological challenge task) was not a significant predictor of earlier smoking lapse. Discussion: These results are discussed in relation to refining theoretical models of the role of distress tolerance in early smoking lapse and the utility of such models in the development of specialized treatment approaches for smoking cessation. PMID:19372572

  9. Time-lapse in the IVF-lab: how should we assess potential benefit?

    PubMed

    Armstrong, S; Vail, A; Mastenbroek, S; Jordan, V; Farquhar, C

    2015-01-01

    Time-lapse imaging of embryos has been widely introduced to fertility laboratories worldwide with the aim of identifying the best quality embryos to transfer that will ultimately improve IVF success rates. In this opinion paper, we explore the lack of evidence of benefit of this novel intervention, analyse the methodological flaws of current studies, offer ideal study designs that assess the various features of time-lapse imaging, and discuss forthcoming studies. In particular, we emphasize the ethical aspects of hastily adopting a costly technology without current high level evidence of improved live birth rates, safety and cost effectiveness.

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

    SciTech Connect

    Singha, Kamini; Day-Lewis, Frederick D.; Johnson, Timothy C.; Slater, Lee D.

    2015-03-15

    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.

  11. Lapses in Sustained Attention and Their Relation to Executive Control and Fluid Abilities: An Individual Differences Investigation

    ERIC Educational Resources Information Center

    Unsworth, Nash; Redick, Thomas S.; Lakey, Chad E.; Young, Diana L.

    2010-01-01

    A latent variable analysis was conducted to examine the nature of individual differences in lapses of attention and their relation to executive and fluid abilities. Participants performed a sustained attention task along with multiple measures of executive control and fluid abilities. Lapses of attention were indexed based on the slowest reaction…

  12. Full waveform inversion of repeating seismic events to estimate time-lapse velocity changes

    NASA Astrophysics Data System (ADS)

    Kamei, R.; Lumley, D.

    2017-05-01

    Seismic monitoring provides valuable information regarding the time-varying changes in subsurface physical properties caused by natural or man-made processes. However, the resulting changes in the earth's subsurface properties are often small both in terms of magnitude and spatial extent, leading to minimal time-lapse differences in seismic amplitude or traveltime. In order to better extract information from the time-lapse data, we show that exploiting the full seismic waveform information can be critical. In this study, we develop and test methods of full waveform inversion that estimate an optimal subsurface model of time-varying elastic properties in order to fit the observed time-lapse seismic data with predicted waveforms based on numerical solutions of the wave equation. Time-lapse full waveform inversion is nonlinear and non-unique, and depends on the knowledge of the baseline velocity model before a change, and (non-)repeatability of earthquake source and sensor parameters, and of ambient and cultural noise. We propose to use repeating earthquake data sets acquired with permanent arrays of seismic sensors to enhance the repeatability of source and sensor parameters. We further develop and test time-lapse parallel, double-difference and bootstrapping inversion strategies to mitigate the dependence on the baseline velocity model. The parallel approach uses a time-invariant full waveform inversion method to estimate velocity models independently of the different source event times. The double-difference approach directly estimates velocity changes from time-lapse waveform differences, requiring excellent repeatability. The bootstrapping approach inverts for velocity models sequentially in time, implicitly constraining the time-lapse inversions, while relaxing an explicit requirement for high data repeatability. We assume that prior to the time-lapse inversion, we can estimate the true source locations and the origin time of the events, and also we can also

  13. Automated time-lapse microscopy and high-resolution tracking of cell migration

    SciTech Connect

    Fotos, Joseph S.; Vivek, Patel P.; Karin, Norm J.; Temburni, Murali; Koh, John T.; Galileo, Deni S.

    2006-08-09

    The study of cell motility is greatly enhanced by using a fully-automated high-throughput time-lapse microscopy system that is capable of collecting and analyzing data (1) from closely-spaced time points (seconds to minutes), (2) over long periods (hours to days), (3) from multiple areas of interest, (4) under several different experimental conditions simultaneously. Time-lapse video images collected under phase contrast and fluorescent illumination were analyzed using parameters of migration velocity, total accumulated distance (path length), and directionality for individual cells or for averaged cell populations. Quantitation of ''scratch'' or ''wound healing'' assays revealed unique motility dynamics of drug-treated and adhesion molecule-transfected cells with high resolution and, thus, is a vast distinct improvement of current methods. Several fluorescent vital labeling methods commonly used for end-point analyses, including GFP expression, were evaluated and most were useful for time-lapse studies under specific conditions. For example, fluorescently-labeled tumor cells were seeded onto cell monolayers expressing ectopic adhesion molecules displayed altered migration velocities compared to tumor cells plated directly onto culture dishes. The techniques described here revealed cell motility behavior not discernable by previously-used methods. We propose that quantitative time-lapse video analysis will foster the creation new cell motility assays, and increase the resolution and accuracy of existing assays.

  14. Dynamic Association between Negative Affect and Alcohol Lapses following Alcohol Treatment

    ERIC Educational Resources Information Center

    Witkiewitz, Katie; Villarroel, Nadia Aracelliz

    2009-01-01

    Clinical research has found a strong association between negative affect and returning to alcohol use after a period of abstinence. Yet little is known about the probability of a lapse given a particular level of negative affect or whether there is a reciprocal relationship between negative affect and alcohol use across time. The goal of the…

  15. A Typology of University Ethical Lapses: Types, Levels of Seriousness, and Originating Location

    ERIC Educational Resources Information Center

    Kelley, Patricia C.; Chang, Pepe Lee

    2007-01-01

    Scandals ranging from National Collegiate Athletic Association (NCAA) violations to falsified research results have fueled criticism of America's universities. Sports violations, research manipulation, gender discrimination, and other ethical lapses affect an entire institution as they have a spillover effect on its reputation. The results of…

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

    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.

  17. 2D Time-lapse Seismic Tomography Using An Active Time Constraint (ATC) Approach

    EPA Science Inventory

    We propose a 2D seismic time-lapse inversion approach to image the evolution of seismic velocities over time and space. The forward modeling is based on solving the eikonal equation using a second-order fast marching method. The wave-paths are represented by Fresnel volumes rathe...

  18. 30 CFR 585.530 - What must I do if my financial assurance lapses?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What must I do if my financial assurance lapses? 585.530 Section 585.530 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE... Payments and Financial Assurance Requirements Changes in Financial Assurance § 585.530 What must I do if my...

  19. 30 CFR 585.530 - What must I do if my financial assurance lapses?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What must I do if my financial assurance lapses? 585.530 Section 585.530 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE... Payments and Financial Assurance Requirements Changes in Financial Assurance § 585.530 What must I do if my...

  20. 30 CFR 585.530 - What must I do if my financial assurance lapses?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What must I do if my financial assurance lapses? 585.530 Section 585.530 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE... Payments and Financial Assurance Requirements Changes in Financial Assurance § 585.530 What must I do if my...

  1. 3D inversion of time-lapse CSEM data for reservoir monitoring

    NASA Astrophysics Data System (ADS)

    Black, N.; Wilson, G. A.; Zhdanov, M. S.

    2010-12-01

    Effective reservoir monitoring requires time-lapse reservoir information throughout the interwell volume. The ability to understand and control reservoir behavior over the course of production allows for optimization of reservoir performance and production strategies. Good monitoring information makes it possible to improve the timing and location of new drilling (for both production and injection wells), to recognize flow paths, and to map oil that has been bypassed. Recent studies have inferred the feasibility of time-lapse marine controlled-source electromagnetic (CSEM) methods for the monitoring of offshore oil and gas fields. However, quantitative interpretations to ascertain what reservoir information may be recovered have not been performed. The time-lapse CSEM inverse problem can be highly constrained since the geometry of the reservoir is established prior from high resolution seismic surveys, rock and fluid properties are measured from well logs, and multiple history matched production scenarios are contained in dynamic reservoir models. We present a 3D inversion study of synthetic time-lapse CSEM data modeled from dynamic reservoir simulations. We demonstrate that even with few constraints on the model, the hydrocarbon-water front can be recovered from 3D inversion.

  2. First successful pregnancies following embryo selection using Time-lapse technology in Iran: Case report

    PubMed Central

    Faramarzi, Azita; Khalili, Mohammad Ali; Soleimani, Mehrdad

    2015-01-01

    Background: Embryo selection is a vital part of in vitro fertilization (IVF) programs, with morphology-based grading systems having been widely used for decades. Time-lapse imaging combined with embryo morph kinetics may proffer a non-invasive means for improving embryo selection. We report the first ongoing and chemical pregnancies using Time-lapse embryo scope to select best embryos for transfer in Iran. Cases: A case with tubal factor infertility was admitted to IVF program with normozoospermia. After ovarian hyper stimulation, 6 COCs were retrieved and inseminated with 25,000 progressive sperms/ oocyte. Five zygotes were placed individually into the micro wells of equilibrated embryo scope dish for Time-lapse observation, and incubated at 37°C, 5% CO2. On day 3, single embryo transfer (SET) took place based on kinetic parameters of the embryos. Clinical pregnancy was confirmed 7 weeks after SET. The second case with history of previous ICSI failure was admitted with azoospermia. Nine MII oocytes underwent ICSI, and incubated in Time-lapse facilities. The rest of procedures were followed as described for case 1. Chemical pregnancy was confirmed 15 days after SET. Conclusion: This approach opens a way to select best embryo non-invasively for SET; thus, increasing implantation, while reducing multiple pregnancy complications. PMID:26131014

  3. Time-lapse motion picture technique applied to the study of geological processes

    USGS Publications Warehouse

    Miller, R.D.; Crandell, D.R.

    1959-01-01

    Light-weight, battery-operated timers were built and coupled to 16-mm motion-picture cameras having apertures controlled by photoelectric cells. The cameras were placed adjacent to Emmons Glacier on Mount Rainier. The film obtained confirms the view that exterior time-lapse photography can be applied to the study of slow-acting geologic processes.

  4. Feasibility of monitoring gas hydrate production with time-lapse VSP

    SciTech Connect

    Kowalsky, M.B.; Nakagawa, S.; Moridis, G.J.

    2009-11-01

    In this work we begin to examine the feasibility of using time-lapse seismic methods-specifically the vertical seismic profiling (VSP) method-for monitoring changes in hydrate accumulations that are predicted to occur during production of natural gas.

  5. Relative Effectiveness of Continued, Lapsed, and Delayed Smoking Prevention Intervention in Senior High School Students.

    ERIC Educational Resources Information Center

    Eckhardt, Laura; And Others

    1997-01-01

    Reports findings from the final year of a tobacco use prevention project for junior and senior high school students. After three years of intervention with junior high students, researchers assessed the relative effectiveness of continued, lapsed, and delayed interventions in high school. In grade 11, continued intervention students had the lowest…

  6. Estimating topsoil water content of clay soils with data from time-lapse electrical conductivity surveys

    USDA-ARS?s Scientific Manuscript database

    Spatial estimation of soil water content (') at the field, hillslope, or catchment scale is required in numerous applications. Time-lapse electrical resistivity and electrical conductivity surveys were recognized as the useful source of information about both spatial variations in soil water conten...

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

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  9. A Typology of University Ethical Lapses: Types, Levels of Seriousness, and Originating Location

    ERIC Educational Resources Information Center

    Kelley, Patricia C.; Chang, Pepe Lee

    2007-01-01

    Scandals ranging from National Collegiate Athletic Association (NCAA) violations to falsified research results have fueled criticism of America's universities. Sports violations, research manipulation, gender discrimination, and other ethical lapses affect an entire institution as they have a spillover effect on its reputation. The results of…

  10. Knowledge of Ethical Lapses and Other Experiences on Clinical Licensure Examinations.

    ERIC Educational Resources Information Center

    Feil, Philip; Meeske, Jessica; Fortman, Jared

    1999-01-01

    A survey of 429 general dentists attempted to verify anecdotal reports of ethical lapses in clinical dental licensing examinations. It found significant occurrence of not arranging followup care for the patient even though indicated, intentional creation of lesions, premature treatment for the purpose of the examinations, coercing patients into…

  11. 75 FR 68037 - Proposed Information Collection (Application for Reinstatement (Insurance Lapsed More Than 6...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-04

    ... collection of information, including each proposed extension of a currently approved collection, and allow 60... to reinstate a claimant's Government Life Insurance and/or Total Disability Income Provision. DATES...: Application for Reinstatement (Insurance Lapsed More than 6 Months), Government Life Insurance and/or...

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

    ERIC Educational Resources Information Center

    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…

  13. Time-Lapse Motion Picture Technique Applied to the Study of Geological Processes.

    PubMed

    Miller, R D; Crandell, D R

    1959-09-25

    Light-weight, battery-operated timers were built and coupled to 16-mm motion-picture cameras having apertures controlled by photoelectric cells. The cameras were placed adjacent to Emmons Glacier on Mount Rainier. The film obtained confirms the view that exterior time-lapse photography can be applied to the study of slow-acting geologic processes.

  14. 2D Time-lapse Seismic Tomography Using An Active Time Constraint (ATC) Approach

    EPA Science Inventory

    We propose a 2D seismic time-lapse inversion approach to image the evolution of seismic velocities over time and space. The forward modeling is based on solving the eikonal equation using a second-order fast marching method. The wave-paths are represented by Fresnel volumes rathe...

  15. 37 CFR 1.317 - Lapsed patents; delayed payment of balance of issue fee.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... payment of balance of issue fee. 1.317 Section 1.317 Patents, Trademarks, and Copyrights UNITED STATES... Processing Provisions Allowance and Issue of Patent § 1.317 Lapsed patents; delayed payment of balance of... is required at the time the issue fee is paid, any remaining balance of the issue fee is to be paid...

  16. 37 CFR 1.317 - Lapsed patents; delayed payment of balance of issue fee.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... payment of balance of issue fee. 1.317 Section 1.317 Patents, Trademarks, and Copyrights UNITED STATES... Processing Provisions Allowance and Issue of Patent § 1.317 Lapsed patents; delayed payment of balance of... is required at the time the issue fee is paid, any remaining balance of the issue fee is to be paid...

  17. 37 CFR 1.317 - Lapsed patents; delayed payment of balance of issue fee.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... payment of balance of issue fee. 1.317 Section 1.317 Patents, Trademarks, and Copyrights UNITED STATES... Processing Provisions Allowance and Issue of Patent § 1.317 Lapsed patents; delayed payment of balance of... is required at the time the issue fee is paid, any remaining balance of the issue fee is to be paid...

  18. 37 CFR 1.317 - Lapsed patents; delayed payment of balance of issue fee.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... payment of balance of issue fee. 1.317 Section 1.317 Patents, Trademarks, and Copyrights UNITED STATES... Processing Provisions Allowance and Issue of Patent § 1.317 Lapsed patents; delayed payment of balance of... is required at the time the issue fee is paid, any remaining balance of the issue fee is to be paid...

  19. Time-lapse Measurements of Scholte Wave Velocity Over a Compacting Oil Field

    NASA Astrophysics Data System (ADS)

    Wills, P. B.; Hatchell, P. J.

    2007-12-01

    Acquisition of time-lapse seismic data over producing oil and gas fields is a proven method for optimizing hydrocarbon production. Most current data have been acquired using towed-streamer seismic vessels but new systems incorporating permanent Ocean Bottom Cable (OBC) systems are gaining in popularity, both as a way to achieve better repeatability and also to reduce the cost of acquiring many time-lapse repeats of the baseline survey. Over the last three years, more than seven repeat data sets have been acquired at the permanent OBC system installed (by the operator, BP) over the Valhall oil field located offshore Norway. This system contains ~2400 four-component receiver stations that are recorded using a dense areal shot grid ("carpet" shoot) that provides high fold and has delivered excellent time-lapse signals starting from the first repeat occurring just three months after the baseline. Time-lapse OBC data are conventionally used to measure amplitude and velocity changes of body wave reflections (PP and PS) but other measurements are also possible. In particular, Scholte waves are strongly visible on records acquired everywhere in the field on appropriately processed data and, given the high fold (because of the dense shots), Scholte wave velocity and anisotropy time-lapse changes obtained with both hydrophone and geophone sensors are accurately and robustly estimated. The resulting shallow velocity maps are very sensitive to the seabed strains and show large velocity changes overlying deep production. Also, reconstruction of compressional "head wave" velocity difference measurements and vertically propagating shear wave shallow time-lapse statics produce maps that resemble the Scholte wave maps, with differences that reflect the physics of the propagation modes and effective fold. A reservoir model that includes deep reservoir volume changes together with appropriate geomechanical properties in the overburden and a shallow conversion of strain to velocity is

  20. Time-Lapse inversion of EM Tomography data for polymer-injected hydrocarbon reservoirs

    NASA Astrophysics Data System (ADS)

    Cheon, Seiwook; Park, Chanho; Nam, Myung Jin; Son, Jeong-Sul

    2015-04-01

    Polymer flooding is a method to increase the production of hydrocarbon reservoir by injecting polymer solution into the reservoir. For a study on the monitoring fluid variation within the reservoir, we first make analysis on seismic- and electromagnetic (EM)- tomography responses for seismic and electrical-resistivity rock physics models (RPMs) of the reservoir considering polymer fluid. Constructing RPMs are dependent on not only geologic characteristics of reservoir but also reservoir parameters such as fluid-type, fluid saturation, pressure and temperature. When making RPM for monitoring analysis, we assume the geology does not changes while reservoir parameters change to affect responses of seismic and EM tomography data. Specifically when constructing electrical-resistivity RPM, we consider three different types of hydrocarbon reservoirs, which are clean sand, shaly sand, sand-shale lamination, while considering two different types of waters (fresh water and salt water) to make 2wt% polymer solution. To compute time lapse EM and seismic tomography responses for corresponding RPMs of polymer-injected reservoirs, we used 2.5D finite element EM modeling algorithm and staggered-grid finite difference elastic modeling algorithm, respectively. Comparison between sensitivities of seismic and EM tomography to polymer injection confirms that EM tomography is more sensitivity to the polymer injection. For the evaluation of the potential of EM tomography to monitor polymer flooding, this study subsequently develops an efficient time-lapse EM tomography inversion algorithm based on the 2.5D EM tomography modeling. Using the inversion algorithm, we inverted the time-lapse EM tomography data to construct true resistivity models of polymer-injected reservoirs and analyze differences between them. From the time-lapse inversion results, we can observe the differences in time lapse responses between using fresh water and salt water have been decreased in the inverted time-lapse

  1. Diurnal Wind Regimes and Lapse-Rate Variability Over Clean and Debris-Covered Ice

    NASA Astrophysics Data System (ADS)

    Flowers, G. E.; Young, E.

    2015-12-01

    Near-surface winds and air temperature play an important role in the surface energy balance of glaciers and ice sheets, and can be highly variable in space and time. The increasing fraction of debris-covered ice observed in many retreating alpine glacier environments motivates the study of these variables, and the processes that control them, over both clean and debris-covered ice. We use meteorological data collected in the ablation zone of a ~ 5km-long valley glacier in Yukon, Canada, to analyze the diurnal variability of temperature and wind regimes over debris-covered and debris-free ice. Our data reveal pronounced diurnal cycles in temperature lapse rates, wind speeds, and wind directions. Common to both clean and debris-covered areas are: (1) a shallowing of lapse rates in the early morning from 6:00 to 9:00 and a steepening of lapse rates during the day from 9:00 to 16:00, (2) nearly identical lapse rates regardless of surface type between 15:00 and 19:00, and (3) a persistent diurnal wind regime in which up-valley winds occur from late morning to evening, peaking at 16:00-17:00, and relatively weaker down-valley winds occur overnight. Significant differences between the clean-ice and debris-covered sites are also evident in the data, namely: (1) much steeper night-time lapse rates over debris-covered ice than clean ice, (2) the occurrence of steepest lapse rates overnight for debris-covered ice and in late afternoon (around 16:00) for clean ice, and (3) a more pronounced diurnal cycle in windspeed over debris-covered ice than clean ice, despite all stations exhibiting evidence of the diurnal changes in wind direction. The patterns described above conform to a model of weak katabatic flow at night and relatively stronger up-valley winds during the day, peaking in late afternoon. Though absolute temperatures over clean and debris-covered ice are markedly different during the day, lapse rates over both surfaces evolve similarly through the day to achieve steep

  2. Full waveform inversion of repeating seismic events to estimate time-lapse velocity changes

    NASA Astrophysics Data System (ADS)

    Kamei, R.; Lumley, D.

    2017-02-01

    Seismic monitoring provides valuable information regarding the time-varying changes in subsurface physical properties caused by natural or man-made processes. However, the resulting changes in the earth's subsurface properties are often small both in terms of magnitude and spatial extent, leading to minimal time-lapse differences in seismic amplitude or traveltime. In order to better extract information from the time-lapse data, we show that exploiting the full seismic waveform information can be critical. In this study, we develop and test methods of full waveform inversion that estimate an optimal subsurface model of time-varying elastic properties in order to fit the observed time-lapse seismic data with predicted waveforms based on numerical solutions of the wave equation. Time-lapse full waveform inversion is non-linear and non-unique, and depends on the knowledge of the baseline velocity model before a change, and (non-)repeatability of earthquake source and sensor parameters, and of ambient and cultural noise. We propose to use repeating earthquake data sets acquired with permanent arrays of seismic sensors to enhance the repeatability of source and sensor parameters. We further develop and test time-lapse parallel, double-difference and bootstrapping inversion strategies to mitigate the dependence on the baseline velocity model. The parallel approach uses a time-invariant full waveform inversion method to estimate velocity models independently of the different source event times. The double-difference approach directly estimates velocity changes from time-lapse waveform differences, requiring excellent repeatability. The bootstrapping approach inverts for velocity models sequentially in time, implicitly constraining the time-lapse inversions, while relaxing an explicit requirement for high data repeatability. We assume that prior to the time-lapse inversion, we can estimate the true source locations and the origin time of the events, and also we can also

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

    NASA Astrophysics Data System (ADS)

    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

  4. Developing an EEG-based on-line closed-loop lapse detection and mitigation system

    PubMed Central

    Wang, Yu-Te; Huang, Kuan-Chih; Wei, Chun-Shu; Huang, Teng-Yi; Ko, Li-Wei; Lin, Chin-Teng; Cheng, Chung-Kuan; Jung, Tzyy-Ping

    2014-01-01

    In America, 60% 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-reality environment. When the subjects experienced lapses or failed to respond to events during the experiment, auditory warning 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 warning to subjects suffering momentary cognitive lapses, and assess the efficacy of the warning 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. PMID:25352773

  5. Long-term time-lapse live imaging reveals extensive cell migration during annelid regeneration.

    PubMed

    Zattara, Eduardo E; Turlington, Kate W; Bely, Alexandra E

    2016-03-23

    Time-lapse imaging has proven highly valuable for studying development, yielding data of much finer resolution than traditional "still-shot" studies and allowing direct examination of tissue and cell dynamics. A major challenge for time-lapse imaging of animals is keeping specimens immobile yet healthy for extended periods of time. Although this is often feasible for embryos, the difficulty of immobilizing typically motile juvenile and adult stages remains a persistent obstacle to time-lapse imaging of post-embryonic development. Here we describe a new method for long-duration time-lapse imaging of adults of the small freshwater annelid Pristina leidyi and use this method to investigate its regenerative processes. Specimens are immobilized with tetrodotoxin, resulting in irreversible paralysis yet apparently normal regeneration, and mounted in agarose surrounded by culture water or halocarbon oil, to prevent dehydration but allowing gas exchange. Using this method, worms can be imaged continuously and at high spatial-temporal resolution for up to 5 days, spanning the entire regeneration process. We performed a fine-scale analysis of regeneration growth rate and characterized cell migration dynamics during early regeneration. Our studies reveal the migration of several putative cell types, including one strongly resembling published descriptions of annelid neoblasts, a cell type suggested to be migratory based on "still-shot" studies and long hypothesized to be linked to regenerative success in annelids. Combining neurotoxin-based paralysis, live mounting techniques and a starvation-tolerant study system has allowed us to obtain the most extensive high-resolution longitudinal recordings of full anterior and posterior regeneration in an invertebrate, and to detect and characterize several cell types undergoing extensive migration during this process. We expect the tetrodotoxin paralysis and time-lapse imaging methods presented here to be broadly useful in studying

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

    NASA Astrophysics Data System (ADS)

    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

  7. Lapse time dependence of coda Q: Anisotropic multiple-scattering models and application to the Pyrenees

    NASA Astrophysics Data System (ADS)

    Margerin, Ludovic; Calvet, Marie

    2013-04-01

    The attenuation properties of the crust have been widely explored from measurements of the quality factor of coda waves (Qc) throughout the world. A number of studies have reported an increase of Qc with the lapse time in the coda of shear waves excited by local earthquakes. Based on a single-scattering interpretation, this observation is generally ascribed to depth-dependent attenuation properties in the crust. In recent years a number of observations -in particular seismic wave equipartition- have put forward the importance of multiple scattering in the coda. The main purpose of this study is therefore to clarify the role of multiple scattering in the lapse time dependence of Qc using numerical simulations and observations from the Pyrenees. Thanks to the European project Interreg SISPYR, we collected all available waveform data from various institutions that operate seismological networks along the range. We selected around 5000 waveforms from 159 local earthquakes (with a magnitude larger than 3) which occured between 2001 and 2010. The coda quality factor of short-period S-waves has been measured as a function of the length of the coda window (Lw) for different choices of the onset time of the coda. In the 2-16 Hz frequency band, we observe a transient regime characterized by an increase of Qc with Lw, followed by a stabilization around a plateau whose value depends on the central frequency of the signal and on the location along the range. Using Monte Carlo simulations of wave transport in a variety of random media (exponential, Von-Karman or gaussian heterogeneity power spectra), we demonstrate that the lapse-time dependence of Qc in the Pyrenees may be modeled by anisotropic multiple scattering of seismic waves, without invoking any depth dependence of the attenuation properties in the crust. In our model, anisotropic scattering is quantified by the ratio between the transport and scattering mean path (l*-l). At 6 Hz, we show that pyrenean data require an

  8. Lapse time dependence of coda Q: Anisotropic multiple-scattering models and application to the Pyrenees

    NASA Astrophysics Data System (ADS)

    Calvet, M.; Margerin, L.

    2012-12-01

    The attenuation properties of the crust have been widely explored from measurements of the quality factor of coda waves (Qc) throughout the world. A number of studies have reported an increase of Qc with the lapse time in the coda of shear waves excited by local earthquakes. Based on a single scattering interpretation, this observation is generally ascribed to depth-dependent attenuation properties in the crust. In recent years a number of observations -in particular seismic wave equipartition- have put forward the importance of multiple scattering in the coda. The main purpose of this study is therefore to clarify the role of multiple scattering in the lapse time dependence of Qc using numerical simulations and observations from the Pyrenees. Thanks to the European project Interreg SISPYR, we collected all available waveform data from various institutions that operate seismological networks along the range. We selected around 5000 waveforms from 159 local earthquakes (with a magnitude larger than 3) which occured between 2001 and 2010. The coda quality factor of short-period S-waves has been measured as a function of the length of the coda window (Lw) for different choices of the onset time of the coda. In the 2-16 Hz frequency band, we observe a transient regime characterized by an increase of Qc with Lw, followed by a stabilization around a plateau whose value depends on the central frequency of the signal and on the location along the range. Using Monte Carlo simulations of wave transport in a variety of random media (exponential, Von-Karman or gaussian heterogeneity power spectra), we demonstrate that the lapse-time dependence of Qc in the Pyrenees may be modeled by anisotropic multiple scattering of seismic waves, without invoking any depth dependence of the attenuation properties in the crust. In our model, anisotropic scattering is quantified by the ratio between the transport and scattering mean path (l*/l). At 6 Hz, we show that pyrenean data require an

  9. Time-Lapse Acoustic Impedance Inversion in CO2 Sequestration Study (Weyburn Field, Canada)

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Morozov, I. B.

    2016-12-01

    Acoustic-impedance (AI) pseudo-logs are useful for characterising subtle variations of fluid content during seismic monitoring of reservoirs undergoing enhanced oil recovery and/or geologic CO2 sequestration. However, highly accurate AI images are required for time-lapse analysis, which may be difficult to achieve with conventional inversion approaches. In this study, two enhancements of time-lapse AI analysis are proposed. First, a well-known uncertainty of AI inversion is caused by the lack of low-frequency signal in reflection seismic data. To resolve this difficulty, we utilize an integrated AI inversion approach combining seismic data, acoustic well logs and seismic-processing velocities. The use of well logs helps stabilizing the recursive AI inverse, and seismic-processing velocities are used to complement the low-frequency information in seismic records. To derive the low-frequency AI from seismic-processing velocity data, an empirical relation is determined by using the available acoustic logs. This method is simple and does not require subjective choices of parameters and regularization schemes as in the more sophisticated joint inversion methods. The second improvement to accurate time-lapse AI imaging consists in time-variant calibration of reflectivity. Calibration corrections consist of time shifts, amplitude corrections, spectral shaping and phase rotations. Following the calibration, average and differential reflection amplitudes are calculated, from which the average and differential AI are obtained. The approaches are applied to a time-lapse 3-D 3-C dataset from Weyburn CO2 sequestration project in southern Saskatchewan, Canada. High quality time-lapse AI volumes are obtained. Comparisons with traditional recursive and colored AI inversions (obtained without using seismic-processing velocities) show that the new method gives a better representation of spatial AI variations. Although only early stages of monitoring seismic data are available, time-lapse

  10. The influence of surface characteristics on lapse rates and temperature profiles in areas of complex terrain

    NASA Astrophysics Data System (ADS)

    Pepin, N. C.; Pike, G.; Fower, D.; Schaefer, M.

    2012-12-01

    Temperatures near the ground are often decoupled from free-air equivalents, particularly in areas of complex relief and at high latitudes where cold air drainage occurs particularly when radiation balances become negative. This means that it is hard to predict spatial patterns of surface temperature in such regions. In this study several years of intensive field measurements in complex terrain in northern Finland (Kevo) and Sweden (Abisko) allow detailed examination of the interaction between land surface characteristics (including cryosphere), vegetation, and local/micro-climate in mountain basins. Temperature and vapour pressure were measured every 30 minutes for 5 years (2007-2012) at 60 sites at Kevo and for a winter season (September-June) at 52 sites in Abisko, ranging over 300/600 metres of elevation respectively. In Finland lapse rates vary considerably both seasonally and diurnally, the relative importance of seasonal and diurnal forcing changing throughout the year. The results show intense (up to +80 °C/km) and persistent inversion events during the winter months (NDJ) which are broken up by mechanical effects since there is no diurnal cycle. In the transition from winter into spring (FMA) these inversions still occur but increasing radiation imposes a diurnal pattern on their formation and destruction. As snow cover peaks in spring the interaction between surface albedo, land cover and radiation serves to amplify the diurnal cycle in lapse rates. Daytime lapse rates peak in spring because of an increase in albedo with elevation as dark trees give way to reflective snow. At night inversions rapidly reform. Summer lapse rates are modified (usually weakened) by the presence of open water at low elevations. In Abisko similar processes are shown to be at work, although since the valley system is more open and at a larger spatial scale, the range of lapse rate variability is slightly less and the influence of surface characteristics more subdued. Taken

  11. A hyperbolic slicing condition adapted to Killing fields and densitized lapses

    NASA Astrophysics Data System (ADS)

    Alcubierre, Miguel; Corichi, Alejandro; González, José A.; Núñez, Darío; Salgado, Marcelo

    2003-09-01

    We study the properties of a modified version of the Bona Masso family of hyperbolic slicing conditions. This modified slicing condition has two very important features: in the first place, it guarantees that if a spacetime is static or stationary, and one starts the evolution in a coordinate system in which the metric coefficients are already time independent, then they will remain time independent during the subsequent evolution, i.e. the lapse will not evolve and will therefore not drive the time lines away from the Killing direction. Second, the modified condition is naturally adapted to the use of a densitized lapse as a fundamental variable, which in turn makes it a good candidate for a dynamic slicing condition that can be used in conjunction with some recently proposed hyperbolic reformulations of the Einstein evolution equations.

  12. Ethyl glucuronide for detecting alcohol lapses in patients with an alcohol use disorder.

    PubMed

    Lahmek, Pierre; Michel, Laurent; Diviné, Catherine; Meunier, Nadine; Pham, Béatrice; Cassereau, Catherine; Aussel, Christian; Aubin, Henri-Jean

    2012-03-01

    Urine ethyl glucuronide (EtG) was screened in 75 patients during a hospital-based treatment for an alcohol use disorder. During follow-up, EtG was detected in 35 (14.6%) of the 239 urine samples. Positive screens were found in 22 patients (29%), of whom nine were outpatients (39.1% of all outpatients) and 13 inpatients (25.0% of all inpatients). Of the 22 patients with positive EtG, five (22%) also gave a positive breath alcohol test and 10 (45.5%) reported recent alcohol consumption; 12 (54.5%) gave a negative breath alcohol test and declared no alcohol lapse. Ethyl glucuronide has been found useful in detecting covered lapses.

  13. Feeding behavior of lactating dairy cows as measured by time-lapse photography.

    PubMed

    Vasilatos, R; Wangsness, P J

    1980-03-01

    Evaluation of feeding behavior of ad libitum-fed lactating dairy cows by time-lapse photography revealed 68% of the total feeding activity occurred between the daylight hours of 0600 and 1800. Cows consumed an average of 12.1 meals/day, each 20.9 min in duration. Only 58% of the total defined meal time actually was spent eating, or 253.6 min/cow per day. Estimated meal size and rate of eating, as well as total daily time spent eating, were greater for cows as compared to animals with lower energy demand. Certain feeding characteristics, such as meal frequency and duration, were variable among animals, suggesting that these behaviors may be characteristics of individual cows. Results by time-lapse photography compared well with direct measurement by weigh-cell apparatus.

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

    NASA Astrophysics Data System (ADS)

    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

  15. Temperature lapse rates at restricted thermodynamic equilibrium. Part II: Saturated air and further discussions

    NASA Astrophysics Data System (ADS)

    Björnbom, Pehr

    2016-03-01

    In the first part of this work equilibrium temperature profiles in fluid columns with ideal gas or ideal liquid were obtained by numerically minimizing the column energy at constant entropy, equivalent to maximizing column entropy at constant energy. A minimum in internal plus potential energy for an isothermal temperature profile was obtained in line with Gibbs' classical equilibrium criterion. However, a minimum in internal energy alone for adiabatic temperature profiles was also obtained. This led to a hypothesis that the adiabatic lapse rate corresponds to a restricted equilibrium state, a type of state in fact discussed already by Gibbs. In this paper similar numerical results for a fluid column with saturated air suggest that also the saturated adiabatic lapse rate corresponds to a restricted equilibrium state. The proposed hypothesis is further discussed and amended based on the previous and the present numerical results and a theoretical analysis based on Gibbs' equilibrium theory.

  16. Separation method of anomaly source: The time-lapse microgravity data

    NASA Astrophysics Data System (ADS)

    Supriyadi, Santoso, D.; Gunawan, W.; Sarkowi, Gunawan, D.

    2017-07-01

    The time-lapse microgravity anomaly survey was performed in the purpose of searching the subsurface targets to discover an anomaly caused by the survey target. To isolate the source of the anomaly, an existing filter was generally used. For this certain purpose, the filter must be constructed in a way it can receive less than the maximum results. One problem is the source of the unwanted anomaly still attached to the preliminary data. As it is known, the source of time-lapse microgravity anomaly caused by the subsidence and fluid dynamics is idencated by the increases and decreases in groundwater levels. Therefore, the survey should minimize one of these anomalies sources by adjusting the filter field conditions. In this study, the constructed filter is referred as the MBF (Model Based Filter), this filter was constructed with attention-dimensional parameter source of the anomaly.

  17. Volumetric monitoring of aqueous two phase system droplets using time-lapse optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Lee, J.; Bathany, C.; Ahn, Y.; Takayama, S.; Jung, W.

    2016-02-01

    We present a volumetric monitoring method to observe the morphological changes of aqueous two phase system (ATPS) droplets in a microfluidic system. Our method is based on time-lapse optical coherence tomography (OCT) which allows the study of the dynamics of ATPS droplets while visualizing their 3D structures and providing quantitative information on the droplets. In this study, we monitored the process of rehydration and deformation of an ATPS droplet in a microfluidic system and quantified the changes of its volume and velocity under both static and dynamic fluid conditions. Our results indicate that time-lapse OCT is a very promising tool to evaluate the unprecedented features of droplet-based microfluidics.

  18. Freeze core sampling to validate time-lapse resistivity monitoring of the hyporheic zone.

    PubMed

    Toran, Laura; Hughes, Brian; Nyquist, Jonathan; Ryan, Robert

    2013-01-01

    A freeze core sampler was used to characterize hyporheic zone storage during a stream tracer test. The pore water from the frozen core showed tracer lingered in the hyporheic zone after the tracer had returned to background concentration in collocated well samples. These results confirmed evidence of lingering subsurface tracer seen in time-lapse electrical resistivity tomographs. The pore water exhibited brine exclusion (ion concentrations in ice lower than source water) in a sediment matrix, despite the fast freezing time. Although freeze core sampling provided qualitative evidence of lingering tracer, it proved difficult to quantify tracer concentration because the amount of brine exclusion during freezing could not be accurately determined. Nonetheless, the additional evidence for lingering tracer supports using time-lapse resistivity to detect regions of low fluid mobility within the hyporheic zone that can act as chemically reactive zones of importance in stream health.

  19. Extratropical lapse rates during the Paleogene and other very hot climates

    NASA Astrophysics Data System (ADS)

    Zamora, R. A.; Korty, R.; Huber, M.; Thomas, D. J.

    2011-12-01

    Middle latitude storms redistribute heat across the planet, pushing warm tropical air poleward on one side and bringing cold polar air equatorward on the other. At the same time they redistribute heat vertically, stabilizing atmospheric lapse rates in the process. The interplay between convective processes and the stabilizing effects of these large-scale systems remains debated, and the purpose of this study is to examine how the relative importance of each varies with climate. We study output from NCAR's Community Atmospheric Model in which carbon dioxide concentrations vary over a wide range: from preindustrial-era levels of 280 ppm to 8960 ppm. One set uses present-day continental distributions while another has geography applicable to the Eocene epoch. As a tool to assess the stability of the atmosphere, we calculate a thermodynamic variable called saturation potential vorticity (P*), which has the property of being identically zero wherever lapse rates are neutral with respect to moist convection, and large where lapse rates are stable. To complement this analysis, we also examine how the heights of the thermal and dynamic tropopauses change. By examining simulations in which carbon dioxide concentrations vary over a wide range of values, we can assess the relative importance of convective processes to middle latitude thermal stratification in progressively warmer climate states. We also examine how the large-scale general circulation evolves in the hottest states, by assessing the relationship between the width of the Hadley circulation and subtropical stability. The controls for the Eocene epoch and preindustrial era cases have stabilites similar to those found in the present-day climate. Our simulations indicate tropical regions are neutral with respect to moist convection while higher latitudes most often have stable lapse rates, especially during the winter months. In the warmer climates, the frequency of convectively neutral air masses increases in both

  20. Government Shutdown: Operations of the Department of Defense During a Lapse in Appropriations

    DTIC Science & Technology

    2013-10-15

    of Fallen Soldiers Act, to provide for payment of death gratuities and other funeral expenses. Both houses had passed the bill unanimously...On October 10, 2013, the President signed H.J.Res. 91, which provides for the payment of death gratuities and other funeral expenses for military...http://www.defense.gov/ home /features/2013/0913_govtshutdown/ (continued...) Government Shutdown: Operations of the Department of Defense During a Lapse

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

    PubMed

    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.

  2. Time-lapse AVO fluid inversion for dynamic reservoir characterization in Delhi Field, Louisiana

    NASA Astrophysics Data System (ADS)

    Putri, Indah Hermansyah

    In the development stage, CO2 injection is becoming more widely used in enhanced oil recovery (EOR). Delhi Oil Field is part of Phases XIII and XIV of the Reservoir Characterization Project (RCP) Colorado School of Mines. The focus of these phases is to monitor the effectiveness of the CO 2 injection in Delhi Field by using multicomponent time-lapse seismic data. In this study, I analyze the amplitude versus offset (AVO) response of the time-lapse P-wave seismic data in order to quantify the fluid probability in the field. RCP acquired four square miles of multicomponent time-lapse seismic in Delhi Field to characterize the field dynamically. RCP's two surveys, monitor 1 and monitor 2, were shot in 2010 and 2011 after the start of CO2 injection in November 2009. Time-lapse AVO modeling was performed. The modeling results show that both the top Tuscaloosa and Paluxy Formations are class III AVO, and change toward class IV AVO by increasing the CO2 saturation in the reservoir. In addition, the Paluxy Formation shows a consistent result between the synthetic and real data, however, the Tuscaloosa Formation is not consistent as it is affected by tuning. AVO fluid inversion (AFI) was performed on both the Tuscaloosa and Paluxy Formations in order to quantify the fluid probability in these formations. The inversion results are confirmed by the pseudo gamma ray model, the porosity model, the permeability model, the pressure model, and the production data. In the Tuscaloosa and Paluxy Formations, oil and CO2 are located in the good quality, high porosity, and high permeability sandstones. The presence of CO2 is also confirmed by the pressure interpretation. Furthermore, production data from both Tuscaloosa and Paluxy Formations confirm the fluid presence in the reservoir.

  3. Analysis of the repeatability of time-lapse 3d vsp multicomponent surveys, delhi field

    NASA Astrophysics Data System (ADS)

    Carvalho, Mariana Fernandes de

    Delhi Field is a producing oil field located in northeastern Louisiana. In order to monitor the CO2 sweep efficiency, time-lapse 3D seismic data have been acquired in this area. Time-lapse studies are increasingly used to evaluate changes in the seismic response induced by the production of hydrocarbons or the injection of water, CO2 or steam into a reservoir. A 4D seismic signal is generated by a combination of production and injection effects within the reservoir as well as non-repeatability effects. In order to get reliable results from time-lapse seismic methods, it is important to distinguish the production and injection effects from the non-repeatability effects in the 4D seismic signal. Repeatability of 4D land seismic data is affected by several factors. The most significant of them are: source and receiver geometry inaccuracies, differences in seismic sources signatures, variations in the immediate near surface and ambient non-repeatable noise. In this project, two 3D multicomponent VSP surveys acquired in Delhi Field were used to quantify the relative contribution of each factor that can affect the repeatability in land seismic data. The factors analyzed in this study were: source and receiver geometry inaccura- cies, variations in the immediate near surface and ambient non-repeatable noise. This study showed that all these factors had a significant impact on the repeatability of the successive multicomponent VSP surveys in Delhi Field. This project also shows the advantages and disadvantages in the use of different repeata- bility metrics, normalized-root-mean-square (NRMS) difference and signal-to-distortion ratio (SDR) attribute, to evaluate the level of seismic repeatability between successive time-lapse seismic surveys. It is observed that NRMS difference is greatly influenced by time-shifts and that SDR attribute combined with the time-shift may give more distinct and representative repeatability information than the NRMS difference.

  4. TIME-LAPSE SEISMIC MODELING & INVERSION OF CO2 SATURATION FOR SEQUESTRATION AND ENHANCED OIL RECOVERY

    SciTech Connect

    Mark A. Meadows

    2006-03-31

    Injection of carbon dioxide (CO2) into subsurface aquifers for geologic storage/sequestration, and into subsurface hydrocarbon reservoirs for enhanced oil recovery, has become an important topic to the nation because of growing concerns related to global warming and energy security. In this project we developed new ways to predict and quantify the effects of CO2 on seismic data recorded over porous reservoir/aquifer rock systems. This effort involved the research and development of new technology to: (1) Quantitatively model the rock physics effects of CO2 injection in porous saline and oil/brine reservoirs (both miscible and immiscible). (2) Quantitatively model the seismic response to CO2 injection (both miscible and immiscible) from well logs (1D). (3) Perform quantitative inversions of time-lapse 4D seismic data to estimate injected CO2 distributions within subsurface reservoirs and aquifers. This work has resulted in an improved ability to remotely monitor the injected CO2 for safe storage and enhanced hydrocarbon recovery, predict the effects of CO2 on time-lapse seismic data, and estimate injected CO2 saturation distributions in subsurface aquifers/reservoirs. We applied our inversion methodology to a 3D time-lapse seismic dataset from the Sleipner CO2 sequestration project, Norwegian North Sea. We measured changes in the seismic amplitude and traveltime at the top of the Sleipner sandstone reservoir and used these time-lapse seismic attributes in the inversion. Maps of CO2 thickness and its standard deviation were generated for the topmost layer. From this information, we estimated that 7.4% of the total CO2 injected over a five-year period had reached the top of the reservoir. This inversion approach could also be applied to the remaining levels within the anomalous zone to obtain an estimate of the total CO2 injected.

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

    NASA Astrophysics Data System (ADS)

    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

  6. Direct targeting of proteins to lipid droplets demonstrated by time-lapse live cell imaging.

    PubMed

    Tanaka, Torahiko; Kuroda, Kazumichi; Ikeda, Masanori; Kato, Nobuyuki; Shimizu, Kazufumi; Makishima, Makoto

    2013-11-01

    A protein that specifically targets lipid droplets (LDs) was created by connecting two domains of nonstructural protein 4B containing amphipathic helices from hepatitis C virus. We demonstrated its direct targeting and accumulation to the LD surface by time-lapse live cell imaging, comparable to those observed with adipose differentiation-related protein. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  7. Evaluating four-dimensional time-lapse electrical resistivity tomography for monitoring DNAPL source zone remediation

    NASA Astrophysics Data System (ADS)

    Power, Christopher; Gerhard, Jason I.; Karaoulis, Marios; Tsourlos, Panagiotis; Giannopoulos, Antonios

    2014-07-01

    Practical, non-invasive tools do not currently exist for mapping the remediation of dense non-aqueous phase liquids (DNAPLs). Electrical resistivity tomography (ERT) exhibits significant potential but has not yet become a practitioner's tool due to challenges in interpreting the survey results at real sites. This study explores the effectiveness of recently developed four-dimensional (4D, i.e., 3D space plus time) time-lapse surface ERT to monitor DNAPL source zone remediation. A laboratory experiment demonstrated the approach for mapping a changing NAPL distribution over time. A recently developed DNAPL-ERT numerical model was then employed to independently simulate the experiment, providing confidence that the DNAPL-ERT model is a reliable tool for simulating real systems. The numerical model was then used to evaluate the potential for this approach at the field scale. Four DNAPL source zones, exhibiting a range of complexity, were initially simulated, followed by modeled time-lapse ERT monitoring of complete DNAPL remediation by enhanced dissolution. 4D ERT inversion provided estimates of the regions of the source zone experiencing mass reduction with time. Results show that 4D time-lapse ERT has significant potential to map both the outline and the center of mass of the evolving treated portion of the source zone to within a few meters in each direction. In addition, the technique can provide a reasonable, albeit conservative, estimate of the DNAPL volume remediated with time: 25% underestimation in the upper 2 m and up to 50% underestimation at late time between 2 and 4 m depth. The technique is less reliable for identifying cleanup of DNAPL stringers outside the main DNAPL body. Overall, this study demonstrates that 4D time-lapse ERT has potential for mapping where and how quickly DNAPL mass changes in real time during site remediation.

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

    USGS Publications Warehouse

    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.

  9. Evaluating four-dimensional time-lapse electrical resistivity tomography for monitoring DNAPL source zone remediation.

    PubMed

    Power, Christopher; Gerhard, Jason I; Karaoulis, Marios; Tsourlos, Panagiotis; Giannopoulos, Antonios

    2014-07-01

    Practical, non-invasive tools do not currently exist for mapping the remediation of dense non-aqueous phase liquids (DNAPLs). Electrical resistivity tomography (ERT) exhibits significant potential but has not yet become a practitioner's tool due to challenges in interpreting the survey results at real sites. This study explores the effectiveness of recently developed four-dimensional (4D, i.e., 3D space plus time) time-lapse surface ERT to monitor DNAPL source zone remediation. A laboratory experiment demonstrated the approach for mapping a changing NAPL distribution over time. A recently developed DNAPL-ERT numerical model was then employed to independently simulate the experiment, providing confidence that the DNAPL-ERT model is a reliable tool for simulating real systems. The numerical model was then used to evaluate the potential for this approach at the field scale. Four DNAPL source zones, exhibiting a range of complexity, were initially simulated, followed by modeled time-lapse ERT monitoring of complete DNAPL remediation by enhanced dissolution. 4D ERT inversion provided estimates of the regions of the source zone experiencing mass reduction with time. Results show that 4D time-lapse ERT has significant potential to map both the outline and the center of mass of the evolving treated portion of the source zone to within a few meters in each direction. In addition, the technique can provide a reasonable, albeit conservative, estimate of the DNAPL volume remediated with time: 25% underestimation in the upper 2m and up to 50% underestimation at late time between 2 and 4m depth. The technique is less reliable for identifying cleanup of DNAPL stringers outside the main DNAPL body. Overall, this study demonstrates that 4D time-lapse ERT has potential for mapping where and how quickly DNAPL mass changes in real time during site remediation. Copyright © 2014 Elsevier B.V. All rights reserved.

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

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

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

    2013-10-01

    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. 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). 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. 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.

  13. Prediction of Lapse from Associations between Smoking and Situational Antecedents Assessed by Ecological Momentary Assessment

    PubMed Central

    Shiffman, Saul; Balabanis, Mark H.; Gwaltney, Chad J.; Paty, Jean A.; Gnys, Maryann; Kassel, Jon D.; Hickcox, Mary; Paton, Stephanie M.

    2007-01-01

    Smoking is associated with particular moods and activities, but it is not known whether there are individual differences in these associations and whether these differences are associated with success in smoking cessation. We assessed such associations using Ecological Momentary Assessment: real-world, real-time data, collected by palm-top computer. 214 smokers participating in a smoking cessation study provided data during ad lib smoking at baseline. Participants recorded moods and activities each time they smoked and, for comparison, at randomly-selected non-smoking occasions. Situational associations with smoking were captured by examining the associations between smoking and antecedents considered relevant to lapse risk: negative affect (NA), arousal, socializing with others, the presence of others smoking, and consumption of coffee and alcohol. The associations varied across participants, confirming individual differences in situational smoking associations. Survival analyses revealed that only the NA pattern predicted first lapse. The effect was only seen in EMA assessments of NA smoking, and was not captured by questionnaire measures of negative affect smoking, which did not predict lapse risk. Moreover, the effect was not mediated by nicotine dependence. PMID:17628353

  14. Confocal time lapse imaging as an efficient method for the cytocompatibility evaluation of dental composites.

    PubMed

    Attik, Ghania Nina; Gritsch, Kerstin; Colon, Pierre; Grosgogeat, Brigitte

    2014-11-09

    It is generally accepted that in vitro cell material interaction is a useful criterion in the evaluation of dental material biocompatibility. The objective of this study was to use 3D CLSM time lapse confocal imaging to assess the in vitro biocompatibility of dental composites. This method provides an accurate and sensitive indication of viable cell rate in contact with dental composite extracts. The ELS extra low shrinkage, a dental composite used for direct restoration, has been taken as example. In vitro assessment was performed on cultured primary human gingival fibroblast cells using Live/Dead staining. Images were obtained with the FV10i confocal biological inverted system and analyzed with the FV10-ASW 3.1 Software. Image analysis showed a very slight cytotoxicity in the presence of the tested composite after 5 hours of time lapse. A slight decrease of cell viability was shown in contact with the tested composite extracts compared to control cells. The findings highlighted the use of 3D CLSM time lapse imaging as a sensitive method to qualitatively and quantitatively evaluate the biocompatibility behavior of dental composites.

  15. Efficiency of time-lapse intervals and simple baits for camera surveys of wild pigs

    USGS Publications Warehouse

    Williams, B.L.; Holtfreter, R.W.; Ditchkoff, S.S.; Grand, J.B.

    2011-01-01

    Growing concerns surrounding established and expanding populations of wild pigs (Sus scrofa) have created the need for rapid and accurate surveys of these populations. We conducted surveys of a portion of the wild pig population on Fort Benning, Georgia, to determine if a longer time-lapse interval than had been previously used in surveys of wild pigs would generate similar detection results. We concurrently examined whether use of soured corn at camera sites affected the time necessary for pigs to locate a new camera site or the time pigs remained at a site. Our results suggest that a 9-min time-lapse interval generated dependable detection results for pigs and that soured corn neither attracted pigs to a site any quicker than plain, dry, whole-kernel corn, nor held them at a site longer. Maximization of time-lapse interval should decrease data and processing loads, and use of a simple, available bait should decrease cost and effort associated with more complicated baits; combination of these concepts should increase efficiency of wild pig surveys. ?? 2011 The Wildlife Society.

  16. Extended Time-lapse Intravital Imaging of Real-time Multicellular Dynamics in the Tumor Microenvironment

    PubMed Central

    Harney, Allison S.; Wang, Yarong; Condeelis, John S.; Entenberg, David

    2016-01-01

    In the tumor microenvironment, host stromal cells interact with tumor cells to promote tumor progression, angiogenesis, tumor cell dissemination and metastasis. Multicellular interactions in the tumor microenvironment can lead to transient events including directional tumor cell motility and vascular permeability. Quantification of tumor vascular permeability has frequently used end-point experiments to measure extravasation of vascular dyes. However, due to the transient nature of multicellular interactions and vascular permeability, the kinetics of these dynamic events cannot be discerned. By labeling cells and vasculature with injectable dyes or fluorescent proteins, high-resolution time-lapse intravital microscopy has allowed the direct, real-time visualization of transient events in the tumor microenvironment. Here we describe a method for using multiphoton microscopy to perform extended intravital imaging in live mice to directly visualize multicellular dynamics in the tumor microenvironment. This method details cellular labeling strategies, the surgical preparation of a mammary skin flap, the administration of injectable dyes or proteins by tail vein catheter and the acquisition of time-lapse images. The time-lapse sequences obtained from this method facilitate the visualization and quantitation of the kinetics of cellular events of motility and vascular permeability in the tumor microenvironment. PMID:27341448

  17. Estimating Flow Properties from the Onset of Time-Lapse Changes

    NASA Astrophysics Data System (ADS)

    Vasco, D. W.

    2015-12-01

    Geophysical time-lapse observations are increasingly important for monitoring subsurface fluid flow. Time-lapse data can even be used to characterize spatial variations in the properties of a porous medium. A major impediment to such characterization is the difficulty in connecting flow-related changes to changes geophysical properties. For example, physical models used to relate changes in fluid saturation and pressure to seismic velocity changes often depend upon unknown parameters, or on the detailed distribution of the fluid at intermediate spatial scales. The challange is particularly acute when one tries to relate the magnitudes of saturation and pressure changes to the magnitude of a change in a time-lapse observation. I present an alternative approach for the characterization of a porous medium, based upon the onset of changes of a geophysical attribute, that is applicable when there are a sequence of geophysical surveys. An onset time is the calander time as which a geophysical observable begins to deviate from its initial or background value. In many cases onset times are sensitive to flow properties, such as permeability, and insensitive to the details of the physical model governing the geophysical response. Several examples of the use of onset times will be presented, including the seismic monitoring of injected carbon dioxide and the use of surface deformation data to image fluid flow at depth. Though the technique works best when there are numerous geophysical snapshots, numerical modeling indicates useful results are possible from yearly seismic surveys.

  18. Measuring fast gene dynamics in single cells with time-lapse luminescence microscopy

    PubMed Central

    Mazo-Vargas, Anyimilehidi; Park, Heungwon; Aydin, Mert; Buchler, Nicolas E.

    2014-01-01

    Time-lapse fluorescence microscopy is an important tool for measuring in vivo gene dynamics in single cells. However, fluorescent proteins are limited by slow chromophore maturation times and the cellular autofluorescence or phototoxicity that arises from light excitation. An alternative is luciferase, an enzyme that emits photons and is active upon folding. The photon flux per luciferase is significantly lower than that for fluorescent proteins. Thus time-lapse luminescence microscopy has been successfully used to track gene dynamics only in larger organisms and for slower processes, for which more total photons can be collected in one exposure. Here we tested green, yellow, and red beetle luciferases and optimized substrate conditions for in vivo luminescence. By combining time-lapse luminescence microscopy with a microfluidic device, we tracked the dynamics of cell cycle genes in single yeast with subminute exposure times over many generations. Our method was faster and in cells with much smaller volumes than previous work. Fluorescence of an optimized reporter (Venus) lagged luminescence by 15–20 min, which is consistent with its known rate of chromophore maturation in yeast. Our work demonstrates that luciferases are better than fluorescent proteins at faithfully tracking the underlying gene expression. PMID:25232010

  19. High-resolution imaging characterization of bladder dynamic morphophysiology by time-lapse optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Pan, Y. T.; Wu, Q.; Wang, Z. G.; Brink, P. R.; Du, C. W.

    2005-09-01

    We report an experimental study of the possibility of high-speed optical coherence tomography (OCT) for high-resolution imaging characterization of detrusor dynamic morphophysiology and analysis of the mechanisms that lead to geriatric incontinence (GI). The spontaneous contractility of intact fresh rabbit bladders was imaged with two-dimensional (2D) OCT ex vivo at up to 8frames/s. The time-lapse 2D OCT images were postprocessed by image segmentation and fast-Fourier-transform analysis to characterize the dynamic morphological changes of the bladder contractility. In addition, we studied young and aging rat bladders to analyze the differences in dynamics. Preliminary results of our ex vivo study reveal that time-lapse OCT can track the contractile waves of bladders at high spatial resolution and characterize their dynamic morphophysiology in terms of amplitude, phase, and frequency. The results suggest that time-lapse OCT has the potential to act as a detrusor optical biopsy to enhance the diagnosis of detrusor dysfunction and thus of the mechanisms that lead to GI.

  20. Automated time-lapse microscopy and high-resolution tracking of cell migration.

    PubMed

    Fotos, Joseph S; Patel, Vivek P; Karin, Norman J; Temburni, Murali K; Koh, John T; Galileo, Deni S

    2006-05-01

    We describe a novel fully automated high-throughput time-lapse microscopy system and evaluate its performance for precisely tracking the motility of several glioma and osteoblastic cell lines. Use of this system revealed cell motility behavior not discernable with conventional techniques by collecting data (1) from closely spaced time points (minutes), (2) over long periods (hours to days), (3) from multiple areas of interest, (4) in parallel under several different experimental conditions. Quantitation of true individual and average cell velocity and path length was obtained with high spatial and temporal resolution in "scratch" or "wound healing" assays. This revealed unique motility dynamics of drug-treated and adhesion molecule-transfected cells and, thus, this is a considerable improvement over current methods of measurement and analysis. Several fluorescent vital labeling methods commonly used for end-point analyses (GFP expression, DiO lipophilic dye, and Qtracker nanocrystals) were found to be useful for time-lapse studies under specific conditions that are described. To illustrate one application, fluorescently labeled tumor cells were seeded onto cell monolayers expressing ectopic adhesion molecules, and this resulted in consistently reduced tumor cell migration velocities. These highly quantitative time-lapse analysis methods will promote the creation of new cell motility assays and increase the resolution and accuracy of existing assays.

  1. Time-lapse cross-hole electrical resistivity tomography monitoring effects of an urban tunnel

    NASA Astrophysics Data System (ADS)

    Bellmunt, F.; Marcuello, A.; Ledo, J.; Queralt, P.; Falgàs, E.; Benjumea, B.; Velasco, V.; Vázquez-Suñé, E.

    2012-12-01

    Tunnel construction in urban areas has recently become a topic of interest and has increased the use of tunnel boring machines. Monitoring subsurface effects due to tunnel building in urban areas with conventional surface geophysical techniques is not an easy task because of space constraints. Taking advantage of the construction of a new metro line in Barcelona (Spain), a geoelectrical experiment, which included borehole logging and time-lapse cross-hole measurements using permanent electrode deployments, was designed to characterise and to study the subsurface effects of the tunnel drilling in a test site. We present a case study in which the differences between time-lapse cross-hole resistivity measurements acquired before, during and after the tunnel drilling below the test site have been calculated using three different procedures: a constrained time-lapse inversion, a model subtraction and an inversion of the normalised data ratio. The three procedures have provided satisfactory images of the resistivity changes and tunnel geometry, but resistivity changes for the tunnel void were lower than predicted by modelling. This behaviour has been explained by considering a conductive zone around the tunnel. Further, an apparent resistivity pseudosection for the cross-hole data, equivalent to the case of the equatorial dipole-dipole on the surface, is introduced.

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

    NASA Astrophysics Data System (ADS)

    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.

  3. Dynamic association between negative affect and alcohol lapses following alcohol treatment.

    PubMed

    Witkiewitz, Katie; Villarroel, Nadia Aracelliz

    2009-08-01

    Clinical research has found a strong association between negative affect and returning to alcohol use after a period of abstinence. Yet little is known about the probability of a lapse given a particular level of negative affect or whether there is a reciprocal relationship between negative affect and alcohol use across time. The goal of the current study was to examine the association between negative affect and drinking behavior in the 1st year following alcohol treatment. The authors applied an associative latent transition analysis to the Project MATCH outpatient data (n = 952) and then replicated the model in the Project MATCH aftercare data (n = 774). Changes in drinking following treatment were significantly associated with current and prior changes in negative affect, and changes in negative affect were related to prior changes in drinking (effect size range = 0.13-0.33). The results supported the hypothesis that negative affect and alcohol lapses are dynamically linked and suggest that targeting the relationship between negative affect and alcohol use could greatly decrease the probability of lapses and improve alcohol treatment outcomes.

  4. Using time-lapse photogrammetric method to study the terminal part of the Perito Moreno glacier

    NASA Astrophysics Data System (ADS)

    Lenzano, M. G.; Toth, C.; Lenzano, L.; Skvarca, P.; Smalley, R.

    2013-05-01

    The changes that are occurring in regional climate affect cryospheric environments and have a direct impact on the hydrological cycle. This work presents a feasibility study on the implementation and performance assessment of time-lapse processing ofstereo image sequence, acquired by calibrated cameras, in order to determine the altimetric and volumetric changes in the terminus of Perito Moreno (PM) glacier. This glacier is located at 50° 28' 23''S, 73° 02' 10''W at the Parque Nacional Los Glaciares, South Patagonia Icefield, Santa Cruz, Argentina. This glacier has experienced minor fluctuations or unusual behavior with respect to others glaciers since early 1960's until nowadays. The time-lapse technique allows for obtaining accurate estimates of deformations and velocity models. Digital Terrain Models (DTMs) were created from images, captured daily from April, 2012 to November, 2012, with a total of 182 days. One of the challenges was maintaining the accurate co-registration of the DTMs, which was essential for the information extraction. The differences between DTMs provided the velocities in the terminal part of PM for the period as it approaches the Peninsula de Magallanes. In additon, the DTMs were validated in order to determine the degree of uncertainty in the estimation of changes in the glacier. Keywords: time-lapse, DTMs, glacier volume change, Perito Moreno.

  5. Global dynamics of selective attention and its lapses in primary auditory cortex

    PubMed Central

    Lakatos, Peter; Barczak, Annamaria; Neymotin, Samuel A; McGinnis, Tammy; Ross, Deborah; Javitt, Daniel C.; O’Connell, Monica Noelle

    2016-01-01

    Previous research demonstrated that while selectively attending to relevant aspects of the external world, the brain extracts pertinent information by aligning its neuronal oscillations to key time points of stimuli or their sampling by sensory organs. This alignment mechanism is termed oscillatory entrainment. We investigated the global, long-timescale dynamics of this mechanism in the primary auditory cortex of nonhuman primates, and hypothesized that lapses of entrainment would correspond to lapses of attention. By examining electrophysiological and behavioral measures we observed that besides the lack of entrainment by external stimuli, attentional lapses were characterized by high amplitude alpha oscillations, with alpha frequency structuring of neuronal ensemble and single unit operations. Strikingly, entrainment and alpha oscillation dominated periods were strongly anti-correlated and fluctuated rhythmically at an ultra-slow rate. Our results indicate that these two distinct brain states represent externally versus internally oriented computational resources engaged by large-scale task-positive and task-negative functional networks. PMID:27618311

  6. Prospective Analysis of Early Lapse to Drinking and Smoking Among Individuals in Concurrent Alcohol and Tobacco Treatment

    PubMed Central

    Holt, Laura J.; Litt, Mark D.; Cooney, Ned L.

    2012-01-01

    The aims of the current study were to examine, prospectively, 1) dynamic changes in affective state, self-efficacy, and urge in the hours before initial smoking and drinking lapses among individuals in concurrent alcohol and smoking treatment, and 2) the extent to which self-efficacy, urge to use, and/or the use of one substance predicted lapse to the other substance. Ninety-six men and women recruited for a clinical trial of concurrent alcohol and tobacco treatment were eligible for inclusion. Only data from those who experienced an initial lapse to drinking (n=29), or smoking (n=32) were included. Two outpatient substance abuse clinics provided concurrent alcohol and smoking treatment on a weekly basis for three months. Ecological Momentary Assessment (EMA) methods were employed over a 28-day monitoring period to assess antecedents to first drink and a 14-day monitoring period was examined for initial smoking lapses. Baseline and EMA measures of positive and negative affect, alcohol/smoking urge, alcohol/smoking abstinence self-efficacy, nicotine withdrawal, and quantity/frequency of alcohol and tobacco use were examined as lapse predictors. Analyses of EMA ratings controlled for the corresponding baseline measure. Smoking lapse among individuals in concurrent alcohol and tobacco treatment was foreshadowed by higher urges to smoke, lower positive mood, and lower confidence to resist smoking. Drinking lapse was preceded by lower confidence to resist smoking, but only among individuals who reported recent smoking. Concurrent alcohol and smoking treatment should focus on the enhancement of abstinence self-efficacy, positive mood, and the curbing of urges in order to offset lapse risk. PMID:22023022

  7. Time-lapse seismic waveform inversion for monitoring near-surface microbubble injection

    NASA Astrophysics Data System (ADS)

    Kamei, R.; Jang, U.; Lumley, D. E.; Mouri, T.; Nakatsukasa, M.; Takanashi, M.

    2016-12-01

    Seismic monitoring of the Earth provides valuable information regarding the time-varying changes in subsurface physical properties that are caused by natural or man-made processes. However, the resulting changes in subsurface properties are often small both in terms of magnitude and spatial extent, leading to seismic data differences that are difficult to detect at typical non-repeatable noise levels. In order to better extract information from the time-lapse data, exploiting the full seismic waveform information can be critical, since detected amplitude or traveltime changes may be minimal. We explore methods of waveform inversion that estimate an optimal model of time-varying elastic parameters at the wavelength scale to fit the observed time-lapse seismic data with modelled waveforms based on numerical solutions of the wave equation. We apply acoustic waveform inversion to time-lapse cross-well monitoring surveys of 64-m well intervals, and estimate the velocity changes that occur during the injection of microbubble water into shallow unconsolidated Quaternary sediments in the Kanto basin of Japan at a depth of 25 m below the surface. Microbubble water is comprised of water infused with air bubbles of a diameter less than 0.1mm, and may be useful to improve resistance to ground liquefaction during major earthquakes. Monitoring the space-time distribution and physical properties of microbubble injection is therefore important to understanding the full potential of the technique. Repeated monitoring surveys (>10) reveal transient behaviours in waveforms during microbubble injection. Time-lapse waveform inversion detects changes in P-wave velocity of less than 1 percent, initially as velocity increases and subsequently as velocity decreases. The velocity changes are mainly imaged within a thin (1 m) layer between the injection and the receiver well, inferring the fluid-flow influence of the fluvial sediment depositional environment. The resulting velocity models

  8. Enhancing Monitoring of Recharge-Related Environmental Remediation Processes Using Time-Lapse Seismic Refraction

    NASA Astrophysics Data System (ADS)

    Gaines, D. P.; Baker, G. S.; Hubbard, S. S.; Watson, D. B.; Jardine, P. M.

    2008-12-01

    The application of time-lapse seismic methods has typically been constrained to large-scale geologic investigations associated with petroleum exploration and exploitation; however, there is growing interest in monitoring near-surface phenomena (e.g., fluid flow in fractured or karstic geologic media, hydraulic recharge, and near-surface anthropogenic manipulations) using time-lapse seismic methods. In order to demonstrate the feasibility of detailed time-lapse seismic refraction tomography (TLSRT), we have monitored a perched water table at Oak Ridge National Laboratory (ORNL) Y-12 site in conjunction with a multi- disciplinary investigation of the fate and transport of contaminants. Due to remnant anthropogenic alterations of the site (i.e., replacement of 0-7 meters of contaminated soil with poorly sorted limestone gravel fill during construction of a seepage basin cap), the near surface hydrology is extremely complex and is hypothesized to have a large influence on infiltration, contaminant distribution, and contaminant remobilization. Understanding the impact of recharge-related flow and transport processes is especially important in regions that are subjected to significant precipitation events, such as at the ORNL Y-12 site. Here, TLSRT techniques are used to monitor the changing geometry of a perched water table located near the covered seepage basin, while coincident time-lapse surface electrical resistivity (TLERT) measurements are used to monitor changes in total dissolved solids due to recharge-related dilution. Data are collected at multiple time intervals (i.e., daily, weekly, monthly, yearly) and at varying stages in the evolution of the perch zone. The resulting seismic data are processed using wavepath eikonal tomography (WET) and differenced to identify areas of variable velocity associated with a change in saturation. The differenced tomograms correlate with discrete point water table measurements; however, the highly variable water table at this

  9. The application of time-lapse photography for the observation of snow processes in mountainous catchments

    NASA Astrophysics Data System (ADS)

    Garvelmann, J.; Pohl, S.; Weiler, M.

    2012-04-01

    For the forecast of snowmelt flood events in mountainous catchments it is very important to know the spatial distribution and temporal evolution of the snowcover. Topography and vegetation have the most important influence on the spatio-temporal variability of the snowcover. In order to accomplish a continuous observation of the quantity and the status of the snowcover, an extensive measurement network consisting of numerous standalone snow and meteorological sensors and time-lapse photography was established in three catchments in the Black Forest, a typical mid latitude medium elevation mountain range. Catchments with different topographic characteristic and areal extent were specifically chosen for this study. Within the catchments, a stratified sampling design was used to cover a wide range of altitudes and exposures. In order to investigate the influence of a vegetation cover on the snow processes beneath sensors and cameras have been installed under the forest canopy and on adjacent open field sites, respectively. In the presented study the application of spatially distributed time-lapse cameras for the observation of snow processes and snowcover properties at the catchment scale will be discussed. Image analysis software was applied to extract information about snowdepth, snow albedo and canopy interception from the digital images. A measurement scale with a black/white board was installed in the focus of every camera to allow a determination of the snowdepth at every camera location while the black/white board was used to provide a white balance for the albedo estimation. The albedo provides important information about the status of the snowcover and its temporal evolution is a crucial factor for the snowmelt energy balance. Furthermore the time-lapse images provided a continuous observation of the forest canopy allowing the estimation of the interception efficiency and the temporal evolution of the snow interception for different topographic situations

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

    PubMed Central

    Serrano, María; González-Utor, Antonio; Ortíz, Nereyda; Badajoz, Vicente; Olaya, Enrique; Prados, Nicolás; Boada, Montse; Castilla, Jose A.

    2017-01-01

    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 was almost

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

    PubMed

    Martínez-Granados, Luis; Serrano, María; González-Utor, Antonio; Ortíz, Nereyda; Badajoz, Vicente; Olaya, Enrique; Prados, Nicolás; Boada, Montse; Castilla, Jose A

    2017-01-01

    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 was almost

  12. Time-lapse borehole radar for monitoring rainfall infiltration through podosol horizons in a sandy vadose zone

    NASA Astrophysics Data System (ADS)

    Strobach, Elmar; Harris, B. D.; Dupuis, J. C.; Kepic, A. W.

    2014-03-01

    The shallow aquifer on the Gnangara Mound, north of Perth, Western Australia, is recharged by winter rainfall. Water infiltrates through a sandy Podosol where cemented accumulation (B-) horizons are common. They are water retentive and may impede recharge. To observe wetting fronts and the influence of soil horizons on unsaturated flow, we deployed time-lapse borehole radar techniques sensitive to soil moisture variations during an annual recharge cycle. Zero-offset crosswell profiling (ZOP) and vertical radar profiling (VRP) measurements were performed at six sites on a monthly basis before, during, and after annual rainfall in 2011. Water content profiles are derived from ZOP logs acquired in closely spaced wells. Sites with small separation between wells present potential repeatability and accuracy difficulties. Such problems could be lessened by (i) ZOP saturated zone velocity matching of time-lapse curves, and (ii) matching of ZOP and VRP results. The moisture contents for the baseline condition and subsequent observations are computed using the Topp relationship. Time-lapse moisture curves reveal characteristic vadose zone infiltration regimes. Examples are (I) full recharge potential after 200 mm rainfall, (II) delayed wetting and impeded recharge, and (III) no recharge below 7 m depth. Seasonal infiltration trends derived from long-term time-lapse neutron logging at several sites are shown to be comparable with infiltration trends recovered from time-lapse crosswell radar measurements. However, radar measurements sample a larger volume of earth while being safer to deploy than the neutron method which employs a radioactive source. For the regime (III) site, where time-lapse radar indicates no net recharge or zero flux to the water table, a simple water balance provides an evapotranspiration value of 620 mm for the study period. This value compares favorably to previous studies at similar test sites in the region. Our six field examples demonstrate

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

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed Central

    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 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. PMID:25811710

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

    SciTech Connect

    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.

  16. Time-lapse 3D ground-penetrating radar during plot-scale infiltration experiments

    NASA Astrophysics Data System (ADS)

    Allroggen, Niklas; Jackisch, Conrad; Tronicke, Jens

    2016-04-01

    In electrical resistive soils, surface-based ground-penetrating radar (GPR) is known as the geophysical tool providing the highest spatial resolution. Thus, 2D and 3D GPR surveys are commonly used for imaging subsurface structures or estimating soil moisture content. Due to its sensitivity to soil moisture and its non-invasive character, GPR provides a large potential to monitor soil moisture variation at high temporal and spatial resolution. As shown in previous experiments, the acquisition of time-lapse GPR data under field conditions requires a high data quality in terms of repeatability as well as spatial and temporal resolution. We present hydrogeophysical field experiments at the plot scale (1m x 1m), during which we record time-lapse 3D GPR. For GPR data acquisition, we use a pulseEKKO PRO GPR system equipped with a pair of 500 MHz antennas in combination with a specially designed metal-free measuring platform. Additionally, we collect tracer and soil moisture data, which are used to improve the interpretation of the GPR data with special focus on preferential flow paths and their structured advective flow field. After an accurate time-lapse GPR data processing, we compare 3D reflection events before and after infiltration and quantitatively interpret their relative time-shift in terms of soil moisture variations. Thereby, we are able to account for basically all of the infiltrated water. The first experiments demonstrate the general applicability of our experimental approach but are limited by the number of acquired time steps and measurement during the sprinkling period (the time of the highest temporal dynamics) are not possible at all. Based on this experience we redesign our experimental setup to continuously collect GPR data during irrigation and infiltration. Thereby, we strongly increase the temporal resolution of our measurements, improve the interpretability of the GPR data, and monitor the temporal and spatial dynamics of shallow subsurface

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

    NASA Astrophysics Data System (ADS)

    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.

  18. Time-lapse lens-free imaging of cell migration in diverse physical microenvironments.

    PubMed

    Mathieu, Evelien; Paul, Colin D; Stahl, Richard; Vanmeerbeeck, Geert; Reumers, Veerle; Liu, Chengxun; Konstantopoulos, Konstantinos; Lagae, Liesbet

    2016-08-16

    Time-lapse imaging of biological samples is important for understanding complex (patho)physiological processes. A growing number of point-of-care biomedical assays rely on real-time imaging of flowing or migrating cells. However, the cost and complexity of integrating experimental models simulating physiologically relevant microenvironments with bulky imaging systems that offer sufficient spatiotemporal resolution limit the use of time-lapse assays in research and clinical settings. This paper introduces a compact and affordable lens-free imaging (LFI) device based on the principle of coherent in-line, digital holography for time-lapse cell migration assays. The LFI device combines single-cell resolution (1.2 μm) with a large field of view (6.4 × 4.6 mm(2)), thus rendering it ideal for high-throughput applications and removing the need for expensive and bulky programmable motorized stages. The set-up is so compact that it can be housed in a standard cell culture incubator, thereby avoiding custom-built stage top incubators. LFI is thoroughly benchmarked against conventional live-cell phase contrast microscopy for random cell motility on two-dimensional (2D) surfaces and confined migration on 1D-microprinted lines and in microchannels using breast adenocarcinoma cells. The quality of the results obtained by the two imaging systems is comparable, and they reveal that cells migrate more efficiently upon increasing confinement. Interestingly, assays of confined migration more readily distinguish the migratory potential of metastatic MDA-MB-231 cells from non-metastatic MCF7 cells relative to traditional 2D migration assays. Altogether, this single-cell migration study establishes LFI as an elegant and useful tool for live-cell imaging.

  19. Minds "at attention": mindfulness training curbs attentional lapses in military cohorts.

    PubMed

    Jha, Amishi P; Morrison, Alexandra B; Dainer-Best, Justin; Parker, Suzanne; Rostrup, Nina; Stanley, Elizabeth A

    2015-01-01

    We investigated the impact of mindfulness training (MT) on attentional performance lapses associated with task-unrelated thought (i.e., mind wandering). Periods of persistent and intensive demands may compromise attention and increase off-task thinking. Here, we investigated if MT may mitigate these deleterious effects and promote cognitive resilience in military cohorts enduring a high-demand interval of predeployment training. To better understand which aspects of MT programs are most beneficial, three military cohorts were examined. Two of the three groups were provided MT. One group received an 8-hour, 8-week variant of Mindfulness-based Mind Fitness Training (MMFT) emphasizing engagement in training exercises (training-focused MT, n = 40), a second group received a didactic-focused variant emphasizing content regarding stress and resilience (didactic-focused MT, n = 40), and the third group served as a no-training control (NTC, n = 24). Sustained Attention to Response Task (SART) performance was indexed in all military groups and a no-training civilian group (CIV, n = 45) before (T1) and after (T2) the MT course period. Attentional performance (measured by A', a sensitivity index) was lower in NTC vs. CIV at T2, suggesting that performance suffers after enduring a high-demand predeployment interval relative to a similar time period of civilian life. Yet, there were significantly fewer performance lapses in the military cohorts receiving MT relative to NTC, with training-focused MT outperforming didactic-focused MT at T2. From T1 to T2, A' degraded in NTC and didactic-focused MT but remained stable in training-focused MT and CIV. In sum, while protracted periods of high-demand military training may increase attentional performance lapses, practice-focused MT programs akin to training-focused MT may bolster attentional performance more than didactic-focused programs. As such, training-focused MT programs should be further examined in cohorts experiencing

  20. Time-lapse camera studies of sea-disposed chemical munitions in Hawaii

    NASA Astrophysics Data System (ADS)

    Edwards, Margo H.; Fornari, Daniel J.; Rognstad, Mark R.; Kelley, Christopher D.; Mah, Christopher L.; Davis, Logan K.; Flores, Kyle R. M.; Main, Erin L.; Bruso, Natalie L.

    2016-06-01

    The interactions between fauna and sea-disposed munitions provide important evidence regarding whether munitions constituents affect the health of the ocean environment and its inhabitants. To date few studies of these interactions have been conducted at deep-water disposal sites; typically observations of fauna in the vicinity of sea-disposed munitions are limited to the few minutes or hours required to collect physical samples at a specific location. During the 2012 Hawaii Undersea Military Munitions Assessment (HUMMA) field program we deployed two deep-sea time-lapse camera systems with the objectives of cataloging the diversity of fauna visiting sea-disposed chemical munitions and observing faunal behavior and physiology. Over the 1- and 3-day deployments we recorded 28 different species of fishes, crustaceans, mollusks, cnidarians, and echinoderms at the two sites. Both cameras captured the previously undocumented behavior of brisingid sea stars repositioning themselves along chemical munitions casings. Despite the fact that brisingid sea stars are able to move, for the duration of both time-lapse experiments they remained on chemical munitions casings. We interpret this result to indicate that the advantages of residing on a hard substrate slightly elevated above the seafloor outweigh the effects of chemical munitions constituents for brisingid sea stars. One type of physiological anomaly observed on several arms of the brisingid sea stars at the time-lapse sites led to the collection and examination of six specimens. As reported by Mah (2015. Deep Sea Res. II, 2015, XX-XX), these physiological features are the result of parasitic crustaceans and are not caused by chemical munitions constituents.

  1. Time-lapse imaging of mitosis after siRNA transfection.

    PubMed

    Mackay, Douglas R; Ullman, Katharine S; Rodesch, Christopher K

    2010-06-06

    Changes in cellular organization and chromosome dynamics that occur during mitosis are tightly coordinated to ensure accurate inheritance of genomic and cellular content. Hallmark events of mitosis, such as chromosome movement, can be readily tracked on an individual cell basis using time-lapse fluorescence microscopy of mammalian cell lines expressing specific GFP-tagged proteins. In combination with RNAi-based depletion, this can be a powerful method for pinpointing the stage(s) of mitosis where defects occur after levels of a particular protein have been lowered. In this protocol, we present a basic method for assessing the effect of depleting a potential mitotic regulatory protein on the timing of mitosis. Cells are transfected with siRNA, placed in a stage-top incubation chamber, and imaged using an automated fluorescence microscope. We describe how to use software to set up a time-lapse experiment, how to process the image sequences to make either still-image montages or movies, and how to quantify and analyze the timing of mitotic stages using a cell-line expressing mCherry-tagged histone H2B. Finally, we discuss important considerations for designing a time-lapse experiment. This strategy is complementary to other approaches and offers the advantages of 1) sensitivity to changes in kinetics that might not be observed when looking at cells as a population and 2) analysis of mitosis without the need to synchronize the cell cycle using drug treatments. The visual information from such imaging experiments not only allows the sub-stages of mitosis to be assessed, but can also provide unexpected insight that would not be apparent from cell cycle analysis by FACS.

  2. High-Resolution Time-Lapse Monitoring of Unsaturated Flow using Automated GPR Data Collection

    NASA Astrophysics Data System (ADS)

    Mangel, A. R.; Moysey, S. M.; Lytle, B. A.; Bradford, J. H.

    2015-12-01

    High-resolution ground-penetrating radar (GPR) data provide the detailed information required to image subsurface structures. Recent advances in GPR monitoring now also make it possible to study transient hydrologic processes, but high-speed data acquisition is critical for this application. We therefore highlight the capabilities of our automated system to acquire time-lapse, high-resolution multifold GPR data during infiltration of water into soils. The system design allows for fast acquisition of constant-offset (COP) and common-midpoint profiles (CMP) to monitor unsaturated flow at multiple locations. Qualitative interpretation of the unprocessed COPs can provide substantial information regarding the hydrologic response of the system, such as the complexities of patterns associated with the wetting of the soil and geophysical evidence of non-uniform propagation of a wetting front. While we find that unprocessed images are informative, we show that the spatial variability of velocity introduced by infiltration events can complicate the images and that migration of the data is an effective tool to improve interpretability of the time-lapse images. The ability of the system to collect high density CMP data also introduces the potential for improving the velocity model along with the image via reflection tomography in the post-migrated domain. We show that for both simulated and empirical time-lapse GPR profiles we can resolve a propagating wetting front in the soil that is in good agreement with the response of in-situ soil moisture measurements. The data from these experiments illustrate the importance of high-speed, high-resolution GPR data acquisition for obtaining insight about the dynamics of hydrologic events. Continuing research is aimed at improving the quantitative analysis of surface-based GPR monitoring data for identifying preferential flow in soils.

  3. Time-Lapse Electrical Geophysical Monitoring of Amendment-Based Biostimulation

    SciTech Connect

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

    2015-12-02

    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 surfacebased ERT in conjunction with limited field sampling to improve spatial

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

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  6. Epikarstic storage and doline structural characterization with time-lapse geophysics (seismic refraction & electrical resistivity)

    NASA Astrophysics Data System (ADS)

    Valois, R.; Galibert, P.; Guérin, R.; Mendes, M.; Plagnes, V.

    2011-12-01

    Karst formations are one of the most challenging environments in terms of groundwater, engineering and environmental issues. Geophysical methods can provide useful subsurface information in karst regions concerning groundwater vulnerability assessment, exploitation or hazard estimation. First, dolines are studied as preferential pathways for the protection of karstic aquifer in south France. Geophysics helps to characterize lateral and underground morphologies of such objects and is able to detect doline hidden by the soil cover too. Electrical resistivity and seismic refraction tomographies provide information about dolines filling and could help to propose a genesis scenario. Time-lapse resistivity measurements show that the studied doline is more vulnerable to infiltration on its sides than at its centre. The epikarst could be defined as a perched aquifer above the massive carbonate rocks; it constitutes a highly fractured zone, which water stock capacities. So, the epikarst was investigated with 3D seismic refraction and results show an important velocity anisotropy linked to the fracturing and weathering of the dolostone. The 3D model presents also some large heterogeneities: a corridor with highly weathered dolostone and an unweathered pinnacle. The corridor is probably situated on vertical joints, which have conducted aggressive water. The associated weathering with residual weathered-rock keeping its initial volume could create a "ghost-rock" corridor. So, the epikarst in the dolostones of the Causse du Larzac (France) seems to be composed by "ghost-rock" developed around a specific direction of fractures. Time-lapse electrical resistivity and seismic refraction velocity were carried out on this epikarst to observe the influence of water saturation on the measurements. The results show important variations for both seismic and electrical methods and are localized in the first 6 m: in the weathered zone. So, time-lapse measurements could more easily identify

  7. Sensitivity of MJO to the CAPE lapse time in the NCAR CAM3

    SciTech Connect

    LIU, P.; Wang, B.; Meehl, Gerald, A.

    2007-09-05

    Weak and irregular boreal winter MJO in the NCAR CAM3 corresponds to very low CAPE background, which is caused by easy-to-occur and over-dominant deep convection indicating the deep convective scheme uses either too low CAPE threshold as triggering function or too large consumption rate of CAPE to close the scheme. Raising the CAPE threshold from default 70 J/kg to ten times large only enhances the CAPE background while fails to noticeably improve the wind mean state and the MJO. However, lengthening the CAPE lapse time from one to eight hours significantly improved the background in CAPE and winds, and salient features of the MJO. Variances, dominant periods and zonal wave numbers, power spectra and coherent propagating structure in winds and convection associated with MJO are ameliorated and comparable to the observations. Lengthening the CAPE lapse time to eight hours reduces dramatically the cloud base mass flux, which prevents effectively the deep convection from occurring prematurely. In this case, partitioning of deep to shallow convection in MJO active area is about 5:4.5 compared to over 9:0.5 in the control run. Latent heat is significantly enhanced below 600 hPa over the central Indian Ocean and the western Pacific. Such partitioning of deep and shallow convection is argued necessary for simulating realistic MJO features. Although the universal eight hours lies in the upper limit of that required by the quasi-equilibrium theory, a local CAPE lapse time for the parameterized cumulus convection will be more realistic.

  8. Time-lapse lens-free imaging of cell migration in diverse physical microenvironments

    PubMed Central

    Mathieu, Evelien; Paul, Colin D.; Stahl, Richard; Vanmeerbeeck, Geert; Reumers, Veerle; Liu, Chengxun; Konstantopoulos, Konstantinos; Lagae, Liesbet

    2016-01-01

    Time-lapse imaging of biological samples is important for understanding complex (patho)physiological processes. A growing number of point-of-care biomedical assays rely on real-time imaging of flowing or migrating cells. However, the cost and complexity of integrating experimental models simulating physiologically relevant microenvironments with bulky imaging systems that offer sufficient spatiotemporal resolution limit the use of time-lapse assays in research and clinical settings. This paper introduces a compact and affordable lens-free imaging (LFI) device based on the principle of coherent in-line, digital holography for time-lapse cell migration assays. The LFI device combines single-cell resolution (1.2 μm) with a large field of view (6.4 × 4.6 mm2), thus rendering it ideal for high-throughput applications and removing the need for expensive and bulky programmable motorized stages. The set-up is so compact that it can be housed in a standard cell culture incubator, thereby avoiding custom-built stage top incubators. LFI is thoroughly benchmarked against conventional live-cell phase contrast microscopy for random cell motility on two-dimensional (2D) surfaces and confined migration on 1D-microprinted lines and in microchannels using breast adenocarcinoma cells. The quality of the results obtained by the two imaging systems is comparable, and they reveal that cells migrate more efficiently upon increasing confinement. Interestingly, assays of confined migration more readily distinguish the migratory potential of metastatic MDA-MB-231 cells from non-metastatic MCF7 cells relative to traditional 2D migration assays. Altogether, this single-cell migration study establishes LFI as an elegant and useful tool for live-cell imaging. PMID:27436197

  9. Time-Lapse Electrical Geophysical Monitoring of Amendment-Based Biostimulation.

    PubMed

    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

  10. Arctic sea-ice variations from time-lapse passive microwave imagery

    NASA Technical Reports Server (NTRS)

    Campbell, W. J.; Ramseier, R. O.; Zwally, H. J.; Gloersen, P.

    1980-01-01

    This paper presents: (1) a short historical review of the passive microwave research on sea ice, which established the observational and theoretical base permitting the interpretation of the first passive microwave images of earth obtained by the Nimbus-5 ESMR; (2) the construction of a time-lapse motion picture film of a 16-month set of serial ESMR images to aid in the formidable data analysis task; and (3) a few of the most significant findings resulting from an early analysis of these data, using selected ESMR images to illustrate these findings.

  11. Time-Lapse Imaging to Examine the Growth Kinetics of Arabidopsis Seedlings in Response to Ethylene.

    PubMed

    Binder, Brad M

    2017-01-01

    Ethylene is well known to inhibit the growth of dark-grown eudicot seedlings. Most studies examine this inhibition after several days of exposure to ethylene. However, such end-point analysis misses transient responses and the dynamic nature of growth regulation. Here, high-resolution, time-lapse imaging is described as a method to gather data about ethylene growth kinetics and movement responses of the hypocotyls of dark-grown seedlings of Arabidopsis thaliana. These methods allow for the characterization of short-term kinetic responses and can be modified for the analysis of roots and seedlings from other species.

  12. Arousing feedback rectifies lapse in performance and corresponding EEG power spectrum.

    PubMed

    Jung, Tzyy-Ping; Huang, Kuan-Chih; Chuang, Chun-Hsiang; Chen, Jian-Ann; Ko, Li-Wei; Chiu, Tzai-Wen; Lin, Chin-Teng

    2010-01-01

    This study explores electroencephalographic (EEG) dynamics and behavioral changes in response to arousing auditory signals presented to individuals experiencing momentary cognitive lapses. Arousing auditory feedback was delivered to the subjects in half of the non-responded lane-deviation events during a sustained-attention driving task, which immediately agitated subject's responses to the events. The improved behavioral performance was accompanied by concurrent power suppression in the theta- and alpha-bands in the lateral occipital cortices. This study further explores the feasibility of estimating the efficacy of arousing feedback presented to the drowsy subjects by monitoring the changes in EEG power spectra.

  13. Refinement of Eocene lapse rates, fossil-leaf altimetry, and North American Cordilleran surface elevation estimates

    NASA Astrophysics Data System (ADS)

    Feng, Ran; Poulsen, Christopher J.

    2016-02-01

    Estimates of continental paleoelevation using proxy methods are essential for understanding the geodynamic, climatic, and geomorphoric evolution of ancient orogens. Fossil-leaf paleoaltimetry, one of the few quantitative proxy approaches, uses fossil-leaf traits to quantify differences in temperature or moist enthalpy between coeval coastal and inland sites along latitudes. These environmental differences are converted to elevation differences using their rates of change with elevation (lapse rate). Here, we evaluate the uncertainty associated with this method using the Eocene North American Cordillera as a case study. To do so, we develop a series of paleoclimate simulations for the Early (∼55-49 Ma) and Middle Eocene (49-40 Ma) period using a range of elevation scenarios for the western North American Cordillera. Simulated Eocene lapse rates over western North America are ∼5 °C/km and 9.8 kJ/km, close to moist adiabatic rates but significantly different from modern rates. Further, using linear lapse rates underestimates high-altitude (>3 km) temperature variability and loss of moist enthalpy induced by non-linear circulation changes in response to increasing surface elevation. Ignoring these changes leads to kilometer-scale biases in elevation estimates. In addition to these biases, we demonstrate that previous elevation estimates of the western Cordillera are affected by local climate variability at coastal fossil-leaf sites of up to ∼8 °C in temperature and ∼20 kJ in moist enthalpy, a factor which further contributes to elevation overestimates of ∼1 km for Early Eocene floras located in the Laramide foreland basins and underestimates of ∼1 km for late Middle Eocene floras in the southern Cordillera. We suggest a new approach for estimating past elevations by comparing proxy reconstructions directly with simulated distributions of temperature and moist enthalpy under a range of elevation scenarios. Using this method, we estimate mean elevations for

  14. Time-lapse CCD imagery of plasma-tail motions in Comet Austin

    NASA Technical Reports Server (NTRS)

    Klinglesmith, Daniel A., III; Niedner, Malcolm B., Jr.; Oliversen, R. J.; Westpfahl, David J.

    1991-01-01

    The appearance of the bright comet Austin 1989c1 in April-May of 1990 allowed us to test a new imaging instrument at the Joint Observatory for Cometary Research (JOCR). It is a 300mm lens/charge coupled device (CCD) system with interference filters appropriate for cometary emissions. The 13 frames were made into a time-lapse movie showing the evolution of the plasma tail. We were able to follow at least two large-scale waves out through the main tail structure. During the sequence, we saw two new tail rays form and undergo similar wave motion.

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

    PubMed Central

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

    2015-01-01

    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. PMID:26339304

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

    NASA Astrophysics Data System (ADS)

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

    PubMed Central

    Sison, Miguel; Chakrabortty, Sabyasachi; Extermann, Jérôme; 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 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. PMID:28230188

  18. In vitro ovarian tumor growth and treatment response dynamics visualized with time-lapse OCT imaging

    PubMed Central

    Evans, Conor L.; Rizvi, Imran; Hasan, Tayyaba; de Boer, Johannes F.

    2010-01-01

    In vitro three-dimensional models for metastatic ovarian cancer have been useful for recapitulating the human disease. These spheroidal tumor cultures, however, can grow in excess of 1 mm in diameter, which are difficult to visualize without suitable imaging technology. Optical coherence tomography (OCT) is an ideal live imaging method for non-perturbatively visualizing these complex systems. OCT enabled detailed observations of the model at both nodular and cellular levels, revealing growth dynamics not previously observed. The development of a time-lapse OCT system, capable of automated, multidimensional acquisition, further provided insights into the growth and chemotherapeutic response of ovarian cancer. PMID:19466138

  19. Time-lapse and slow-motion tracking of temperature changes: response time of a thermometer

    NASA Astrophysics Data System (ADS)

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

    2017-03-01

    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 in a simple yet rigorous way the response time of an alcohol thermometer and show its critical dependence on the properties of the surrounding environment giving insight into instrument characteristics, heat transfer and thermal equilibrium concepts.

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

    PubMed

    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.

  1. Arctic sea-ice variations from time-lapse passive microwave imagery

    USGS Publications Warehouse

    Campbell, W.J.; Ramseier, R.O.; Zwally, H.J.; Gloersen, P.

    1980-01-01

    This paper presents: (1) a short historical review of the passive microwave research on sea ice which established the observational and theoretical base permitting the interpretation of the first passive microwave images of Earth obtained by the Nimbus-5 ESMR; (2) the construction of a time-lapse motion picture film of a 16-month set of serial ESMR images to aid in the formidable data analysis task; and (3) a few of the most significant findings resulting from an early analysis of these data, using selected ESMR images to illustrate these findings. ?? 1980 D. Reidel Publishing Co.

  2. High Lapse Rates in AIRS Retrieved Temperatures in Cold Air Outbreaks

    NASA Technical Reports Server (NTRS)

    Fetzer, Eric J.; Kahn, Brian; Olsen, Edward T.; Fishbein, Evan

    2004-01-01

    The Atmospheric Infrared Sounder (AIRS) experiment, on NASA's Aqua spacecraft, uses a combination of infrared and microwave observations to retrieve cloud and surface properties, plus temperature and water vapor profiles comparable to radiosondes throughout the troposphere, for cloud cover up to 70%. The high spectral resolution of AIRS provides sensitivity to important information about the near-surface atmosphere and underlying surface. A preliminary analysis of AIRS temperature retrievals taken during January 2003 reveals extensive areas of superadiabatic lapse rates in the lowest kilometer of the atmosphere. These areas are found predominantly east of North America over the Gulf Stream, and, off East Asia over the Kuroshio Current. Accompanying the high lapse rates are low air temperatures, large sea-air temperature differences, and low relative humidities. Imagery from a Visible / Near Infrared instrument on the AIRS experiment shows accompanying clouds. These lines of evidence all point to shallow convection in the bottom layer of a cold air mass overlying warm water, with overturning driven by heat flow from ocean to atmosphere. An examination of operational radiosondes at six coastal stations in Japan shows AIRS to be oversensitive to lower tropospheric lapse rates due to systematically warm near-surface air temperatures. The bias in near-surface air temperature is seen to be independent of sea surface temperature, however. AIRS is therefore sensitive to air-sea temperature difference, but with a warm atmospheric bias. A regression fit to radiosondes is used to correct AIRS near-surface retrieved temperatures, and thereby obtain an estimate of the true atmosphere-ocean thermal contrast in five subtropical regions across the north Pacific. Moving eastward, we show a systematic shift in this air-sea temperature differences toward more isothermal conditions. These results, while preliminary, have implications for our understanding of heat flow from ocean to

  3. Time-lapse microscopy patent upheld in Europe: response to Pearce.

    PubMed

    Sterckx, Sigrid; Cockbain, Julian; Pennings, Guido

    2017-02-01

    In this piece, we comment on the article by Pearce earlier in this journal. As Pearce correctly points out, what is fundamentally at issue in ESHRE et al's opposition to Stanford University's European patent on time-lapse microscopy is whether an exclusion from patentability, here of methods of medical diagnosis, should be interpreted narrowly or not. In the present case, the dominant piece of case law from the European Patent Office (EPO) gives a narrow interpretation of what a method of diagnosis must be in order not to be patentable. In their submissions to the EPO, ESHRE et al. have argued that this narrow interpretation is unfounded and incorrect.

  4. 3D Time-lapse Imaging and Quantification of Mitochondrial Dynamics

    NASA Astrophysics Data System (ADS)

    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.

  5. High Lapse Rates in AIRS Retrieved Temperatures in Cold Air Outbreaks

    NASA Technical Reports Server (NTRS)

    Fetzer, Eric J.; Kahn, Brian; Olsen, Edward T.; Fishbein, Evan

    2004-01-01

    The Atmospheric Infrared Sounder (AIRS) experiment, on NASA's Aqua spacecraft, uses a combination of infrared and microwave observations to retrieve cloud and surface properties, plus temperature and water vapor profiles comparable to radiosondes throughout the troposphere, for cloud cover up to 70%. The high spectral resolution of AIRS provides sensitivity to important information about the near-surface atmosphere and underlying surface. A preliminary analysis of AIRS temperature retrievals taken during January 2003 reveals extensive areas of superadiabatic lapse rates in the lowest kilometer of the atmosphere. These areas are found predominantly east of North America over the Gulf Stream, and, off East Asia over the Kuroshio Current. Accompanying the high lapse rates are low air temperatures, large sea-air temperature differences, and low relative humidities. Imagery from a Visible / Near Infrared instrument on the AIRS experiment shows accompanying clouds. These lines of evidence all point to shallow convection in the bottom layer of a cold air mass overlying warm water, with overturning driven by heat flow from ocean to atmosphere. An examination of operational radiosondes at six coastal stations in Japan shows AIRS to be oversensitive to lower tropospheric lapse rates due to systematically warm near-surface air temperatures. The bias in near-surface air temperature is seen to be independent of sea surface temperature, however. AIRS is therefore sensitive to air-sea temperature difference, but with a warm atmospheric bias. A regression fit to radiosondes is used to correct AIRS near-surface retrieved temperatures, and thereby obtain an estimate of the true atmosphere-ocean thermal contrast in five subtropical regions across the north Pacific. Moving eastward, we show a systematic shift in this air-sea temperature differences toward more isothermal conditions. These results, while preliminary, have implications for our understanding of heat flow from ocean to

  6. Estimation and Discrimination of Stochastic Biochemical Circuits from Time-Lapse Microscopy Data

    PubMed Central

    Thorsley, David; Klavins, Eric

    2012-01-01

    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. PMID:23139740

  7. Time-Lapse Evaluation of Interactions Between Biodegradable Mg Particles and Cells.

    PubMed

    Alvarez, Florencia; Lozano Puerto, Rosa M; Pérez-Maceda, Blanca; Grillo, Claudia A; Fernández Lorenzo de Mele, Mónica

    2016-02-01

    Mg-based implants have promising applications as biodegradable materials in medicine for orthopedic, dental, and cardiovascular therapies. During wear and degradation microdebris are released. Time-lapse multidimensional microscopy (MM) is proposed here as a suitable tool to follow, in fixed intervals over 24-h periods, the interaction between cells and particles. Results of MM show interactions of macrophages (J774) with the magnesium particles (MgPa) that led to modifications of cell size and morphology, a decrease in duplication rate, and cell damage. Corrosion products were progressively formed on the surface of the particles and turbulence was generated due to hydrogen development. Changes were more significant after treating MgPa with potassium fluoride. In order to complement MM observations, membrane damage as detected by a lactase dehydrogenase (LDH) assay and mitochondrial activity as detected by a WST-1 assay with macrophages and osteoblasts (MC3T3-E1) were compared. A more significant concentration-dependent effect was detected for macrophages exposed to MgPa than for osteoblasts. Accordingly, complementary data showed that viability and cell cycle seem to be more altered in macrophages. In addition, protein profiles and expression of proteins associated with the adhesion process changed in the presence of MgPa. These studies revealed that time-lapse MM is a helpful tool for monitoring changes of biodegradable materials and the biological surrounding in real time and in situ. This information is useful in studies related to biodegradable biomaterials.

  8. High-resolution, time-lapse imaging for ecosystem-scale phenotyping in the field.

    PubMed

    Brown, Tim; Zimmermann, Christopher; Panneton, Whitney; Noah, Nina; Borevitz, Justin

    2012-01-01

    The high spatial and temporal resolution of data required for high-throughput phenotyping has typically been all but impossible to obtain in field populations of plants. When studies of individual and population genetic variation and microclimate sensor data are combined with phenology data, a landscape-level view of how populations respond to changing environments can be obtained. This chapter will discuss the development of a multi-billion pixel ("gigapixel") camera system that enables the collection of phenology data at up to hourly intervals from in situ plant populations. Such gigapixel time-lapse imaging systems represent a key technological advancement for enabling high-throughput phenotyping in field settings. Gigapixel resolution image datasets allow researchers to record life-history (phenology) data across an entire landscape over multiple seasons. Image data can be wirelessly transmitted to a remote server where it can be accessed online within hours of capture. The time-lapse panoramic images are browsable through an interactive web tool that can be used to compare plant phenology with environmental sensor data collected simultaneously from the field. The high spatial and temporal resolution data can be used to identify individual plant phenology, which can in turn be used to generate complete population level phenotype data. The Gigavision platform is especially powerful when coupled with next-generation population genomic analysis. The Gigavision system permits the rapid identification of the phenotypes and genotypes responding to natural selection in wild populations.

  9. Analysis of compaction initiation in human embryos by using time-lapse cinematography.

    PubMed

    Iwata, Kyoko; Yumoto, Keitaro; Sugishima, Minako; Mizoguchi, Chizuru; Kai, Yoshiteru; Iba, Yumiko; Mio, Yasuyuki

    2014-04-01

    To analyze the initiation of compaction in human embryos in vitro by using time-lapse cinematography (TLC), with the goal of determining the precise timing of compaction and clarifying the morphological changes underlying the compaction process. One hundred and fifteen embryos donated by couples with no further need for embryo-transfer were used in this study. Donated embryos were thawed and processed, and then their morphological behavior during the initiation of compaction was dynamically observed via time-lapse cinematography (TLC) for 5 days. Although the initiation of compaction occurred throughout the period from the 4-cell to 16-cell stage, 99 (86.1 %) embryos initiated compaction at the 8-cell stage or later, with initiation at the 8-cell stage being most frequent (22.6 %). Of these 99 embryos, 49.5 % developed into good-quality blastocysts. In contrast, of the 16 (13.9 %) embryos that initiated compaction prior to the 8-cell stage, only 18.8 % developed into good-quality blastocysts. Embryos that initiated compaction before the 8-cell stage showed significantly higher numbers of multinucleated blastomeres, due to asynchronism in nuclear division at the third mitotic division resulting from cytokinetic failure. The initiation of compaction primarily occurs at the third mitotic division or later in human embryos. Embryos that initiate compaction before the 8-cell stage are usually associated with aberrant embryonic development (i.e., cytokinetic failure accompanied by karyokinesis).

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

    PubMed

    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.

  11. Database for temporal events and spatial object features in time-lapse images

    NASA Astrophysics Data System (ADS)

    Eggers, Charles E.; Trivedi, Mohan M.

    2000-04-01

    We present an image database system with the capability to locate specified object-level merge and separation events in a sequence of time-lapse images. Specifically, the objects of interest are live cells in phase contrast images acquired by scanning cytometry. The system is named TERSIS and it resides on a workstation accessing time lapse images on CD- ROM. The cell objects are segmented and the resulting data are processed to extract a time series and its time derivative series for each spatial feature. Cell objects are tracked through the image sequence by applying similarity metrics to the cell object feature vectors, and cell merge and separation events are located using global image statistics. Multiple hypotheses are generated and scored to determine participating cell objects in merge/separation events. The cell association and time-varying spatial data re stored in a database. A graphical suer interface provides the user with tools to specify queries for specific cellular states and events for recall and display. Primary limitation include the need for an automatic front-end segmenter and increased cell tracking volume. The design of this system is extensible to other object types and forms of sequential image input, including video.

  12. Seismic noise-based time-lapse monitoring of the Valhall overburden

    NASA Astrophysics Data System (ADS)

    Mordret, Aurélien; Shapiro, Nikolaï M.; Singh, Satish

    2014-07-01

    We used two "vintages" of ambient seismic noise recorded at the Valhall Life of the Field Seismic network in 2004 and 2005 to perform a passive time-lapse imaging of the subsurface. First, the cross correlations between each pair of stations were computed for both vintages to extract Scholte waves. Second, the relative velocity variations between the 2004 and 2005 cross correlations were measured on the ballistic waves using the Moving-Window Cross-Spectral technique. Finally, the best quality relative velocity variation measurements were regionalized using a modified eikonal tomography technique. The results, albeit noisy because of the short duration of the available records, show a large patch of increased seismic velocity in the southern part of the network and a weaker anomaly in the northern part. The southern increase of velocity can be attributed to the exploitation of the southern flank of the Valhall reservoir with new wells and is in good agreement with a previous time-lapse study using Scholte waves.

  13. Long-term time-lapse multimodal microscopy for tracking cell dynamics in live tissue

    NASA Astrophysics Data System (ADS)

    Graf, Benedikt W.; Valero, Maria C.; Chaney, Eric J.; Marjanovic, Marina; Boppart, Marni D.; Boppart, Stephen A.

    2011-02-01

    High speed intravital microscopy has emerged as an essential tool for studying cellular dynamics in live tissue. A limitation of this technique, however, is that the timescale that a sample can be continuously imaged is limited by practical considerations to several hours. Long term observation of live tissue is of great interest for a variety of research areas. We present methods for observing long term cellular dynamics in live tissue based on three-dimensional registration of time-lapse intravital microscopy images. For these experiments we utilized a custom multimodal microscope that allows simultaneous and co-registered acquisition of optical coherence (OCM) and multiphoton (MPM) microscopy images. OCM allows the structure of a sample to be visualized based on backscattered light while MPM excited fluorescence allows individual cells and cell function to be visualized. The OCM images of tissue structure are used to register data sets taken at different time points. The transformations of the OCM images are applied to MPM images to determine the migration of cell populations. This method of image registration is applied to in vivo tracking of bone-marrow derived GFP-labeled stem cells in mouse skin following bone marrow transplants from GFP donors into species-matched wildtype hosts. The use of three-dimensional image registration of time-lapse microscopy images enables tracking these cells after local cutaneous injury, and for investigating the role of skin stem cells in wound healing.

  14. The time-lapse AVO difference inversion for changes in reservoir parameters

    NASA Astrophysics Data System (ADS)

    Longxiao, Zhi; Hanming, Gu; Yan, Li

    2016-12-01

    The result of conventional time-lapse seismic processing is the difference between the amplitude and the post-stack seismic data. Although stack processing can improve the signal-to-noise ratio (SNR) of seismic data, it also causes a considerable loss of important information about the amplitude changes and only gives the qualitative interpretation. To predict the changes in reservoir fluid more precisely and accurately, we also need the quantitative information of the reservoir. To achieve this aim, we develop the method of time-lapse AVO (amplitude versus offset) difference inversion. For the inversion of reservoir changes in elastic parameters, we apply the Gardner equation as the constraint and convert the three-parameter inversion of elastic parameter changes into a two-parameter inversion to make the inversion more stable. For the inversion of variations in the reservoir parameters, we infer the relation between the difference of the reflection coefficient and variations in the reservoir parameters, and then invert reservoir parameter changes directly. The results of the theoretical modeling computation and practical application show that our method can estimate the relative variations in reservoir density, P-wave and S-wave velocity, calculate reservoir changes in water saturation and effective pressure accurately, and then provide reference for the rational exploitation of the reservoir.

  15. Tracking CO2 Plume in Deep Saline Formations Utilizing a Time-lapse Pressure Tomography Approach

    NASA Astrophysics Data System (ADS)

    Hu, L.; Bayer, P.; Brauchler, R.

    2015-12-01

    CO2 storage in deep saline formations is considered as an attractive option to cut down greenhouse gas emissions. Among the major challenges is the development of efficient technologies for controlling and monitoring the evolution of CO2 plumes during and after injection in the underground. As an alternative to the most commonly used geophysical approaches for subsurface characterization, we propose a pressure-based tomographical approach to track CO2 plume history. By taking into account the direct relationship between saturation and flow properties, pressure tomography has the potential not only to detect a plume but also to estimate the saturation of CO2. The experimental set-up of pressure tomography involves injection of brine or CO2 at variable depths (sources). We use a time-lapse approach, considering first the CO2-free formation, and then the multi-phase CO2-brine system. By applying a rapid eikonal-based inversion technique, pressure fluctuations at observation locations (receivers) are utilized to reconstruct the spatial distribution of the apparent single-phase and mixed-phase diffusivity. Evolution of the plume shape is then delineated by comparison of diffusivity tomograms derived from different times. Finally, an integrated value of CO2 saturation within the plume is obtained by means of a single-phase proxy. Applicability of this novel approach is evaluated in different virtual formations. The time-lapse pressure tomographic investigation revealed that knowledge about the spatial heterogeneity of permeability has a remarkable impact on proper characterization of plume shape.

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Tracking tracer breakthrough in the hyporheic zone using time‐lapse DC resistivity, Crabby Creek, Pennsylvania

    USGS Publications Warehouse

    Nyquist, Jonathan E.; Toran, Laura; Fang, Allison C.; Ryan, Robert J.; Rosenberry, Donald O.

    2010-01-01

    Characterization of the hyporheic zone is of critical importance for understanding stream ecology, contaminant transport, and groundwater‐surface water interaction. A salt water tracer test was used to probe the hyporheic zone of a recently re‐engineered portion of Crabby Creek, a stream located near Philadelphia, PA. The tracer solution was tracked through a 13.5 meter segment of the stream using both a network of 25 wells sampled every 5–15 minutes and time‐lapse electrical resistivity tomographs collected every 11 minutes for six hours, with additional tomographs collected every 100 minutes for an additional 16 hours. The comparison of tracer monitoring methods is of keen interest because tracer tests are one of the few techniques available for characterizing this dynamic zone, and logistically it is far easier to collect resistivity tomographs than to install and monitor a dense network of wells. Our results show that resistivity monitoring captured the essential shape of the breakthrough curve and may indicate portions of the stream where the tracer lingered in the hyporheic zone. Time‐lapse resistivity measurements, however, represent time averages over the period required to collect a tomographic data set, and spatial averages over a volume larger than captured by a well sample. Smoothing by the resistivity data inversion algorithm further blurs the resulting tomograph; consequently resistivity monitoring underestimates the degree of fine‐scale heterogeneity in the hyporheic zone.

  18. Using a time lapse microgravity model for mapping seawater intrusion around Semarang

    NASA Astrophysics Data System (ADS)

    Supriyadi, Khumaedi, Yusuf, M.; Agung, W.

    2016-03-01

    A modeling of time-lapse microgravity anomaly due to sea water intrusion has been conducted. It used field data of aquifer cross section, aquifer thickness and lithology of research area. Those data were then processed using Grav3D and Surfer. Modeling results indicated that the intrusion of sea water resulting in a time-lapse microgravity anomalies of 0.12 to 0.18 mGal, at soil layer density of 0.15 g/cm3 to 0.3 g/cm3 and at depth of 30 to 100 m. These imply that the areas experiencing seawater intrusion were Tanjung Mas, SPBE Bandarharjo, Brass, Old Market Boom and Johar as the microgravity measured there were in the range of 0.12 to 0.18 mGal and the density contrast were at 0.15 g/cm3 to 0.28 g/cm3. Areas that experienced fluid reduction were Puri Anjasmoro, Kenconowungu and Puspowarno with microgravity changes from -0.06 mGal to -0.18 mGal.

  19. Watching amyloid fibrils grow by time-lapse atomic force microscopy.

    PubMed

    Goldsbury, C; Kistler, J; Aebi, U; Arvinte, T; Cooper, G J

    1999-01-08

    Late-onset diabetes is typically associated with amyloid deposits of fibrillar amylin in the pancreatic islets. Aqueous synthetic human amylin spontaneously forms polymorphic fibrils in vitro, and this system was used to examine the dynamics of fibril assembly. By time-lapse atomic force microscopy (AFM), the growth of individual amylin fibrils on a mica surface was observed over several hours. Prominent was the assembly of a protofibril with an elongation rate in these experiments of 1.1(+/-0.5) nm/minute. The assembly of higher order polymorphic fibrils was also observed. Growth of the protofibrils was bidirectional, i.e. it occurred by elongation at both ends. This ability of AFM to continuously monitor growth, directionality, and changes in morphology for individual fibrils, provides a significant advantage over spectroscopy-based bulk methods which average the growth of many fibrils and typically require 100 to 1000-fold more protein. The time-lapse AFM procedure used for human amylin here is thus likely to be applicable to fibril formation from other amyloid proteins and peptides.

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

    PubMed

    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.

  1. Fluorescence Time-lapse Imaging of the Complete S. venezuelae Life Cycle Using a Microfluidic Device

    PubMed Central

    Schlimpert, Susan; Flärdh, Klas; Buttner, Mark

    2016-01-01

    Live-cell imaging of biological processes at the single cell level has been instrumental to our current understanding of the subcellular organization of bacterial cells. However, the application of time-lapse microscopy to study the cell biological processes underpinning development in the sporulating filamentous bacteria Streptomyces has been hampered by technical difficulties. Here we present a protocol to overcome these limitations by growing the new model species, Streptomyces venezuelae, in a commercially available microfluidic device which is connected to an inverted fluorescence widefield microscope. Unlike the classical model species, Streptomyces coelicolor, S. venezuelae sporulates in liquid, allowing the application of microfluidic growth chambers to cultivate and microscopically monitor the cellular development and differentiation of S. venezuelae over long time periods. In addition to monitoring morphological changes, the spatio-temporal distribution of fluorescently labeled target proteins can also be visualized by time-lapse microscopy. Moreover, the microfluidic platform offers the experimental flexibility to exchange the culture medium, which is used in the detailed protocol to stimulate sporulation of S. venezuelae in the microfluidic chamber. Images of the entire S. venezuelae life cycle are acquired at specific intervals and processed in the open-source software Fiji to produce movies of the recorded time-series. PMID:26967231

  2. Time-lapse imaging of disease progression in deep brain areas using fluorescence microendoscopy

    PubMed Central

    Barretto, Robert P. J.; Ko, Tony H.; Jung, Juergen C.; Wang, Tammy J.; Capps, George; Waters, Allison C.; Ziv, Yaniv; Attardo, Alessio; Recht, Lawrence; Schnitzer, Mark J.

    2013-01-01

    The combination of intravital microscopy and animal models of disease has propelled studies of disease mechanisms and treatments. However, many disorders afflict tissues inaccessible to light microscopy in live subjects. Here we introduce cellular-level time-lapse imaging deep within the live mammalian brain by one- and two-photon fluorescence microendoscopy over multiple weeks. Bilateral imaging sites allowed longitudinal comparisons within individual subjects, including of normal and diseased tissues. Using this approach we tracked CA1 hippocampal pyramidal neuron dendrites in adult mice, revealing these dendrites' extreme stability (>8,000 day mean lifetime) and rare examples of their structural alterations. To illustrate disease studies, we tracked deep lying gliomas by observing tumor growth, visualizing three-dimensional vasculature structure, and determining microcirculatory speeds. Average erythrocyte speeds in gliomas declined markedly as the disease advanced, notwithstanding significant increases in capillary diameters. Time-lapse microendoscopy will be applicable to studies of numerous disorders, including neurovascular, neurological, cancerous, and trauma-induced conditions. PMID:21240263

  3. Prevalence of lapses in academic integrity in two Pakistani medical colleges.

    PubMed

    Shukr, Irfan; Roff, Sue

    2015-05-01

    To determine prevalence of professionalism lapses related to academic integrity by students Pakistani medical colleges. 520 students. Cross sectional. A validated and customized version of Dundee Polyprofessional Inventory-1 for use in Pakistani medical schools was used. The students' perceptions on 47 behaviors were explored. The response rate of students was 92%. Ninety percent or more than 90% of student agreed that 30 of the 47 listed behaviors were wrong. Different percentages of the students admitted doing 44 (94%), out of 47 behaviors. Students thought that fellow students were doing dishonest behaviors far more frequently than they themselves were. The commonest dishonest behaviors admitted were proxy attendance (308, 64%), receiving information about the paper from a student who has already sat in the exam, or themselves providing information about a paper who have yet to sit in it (297, 62%), completing work for another student 291 (61%). There are significant issues related to academic integrity in Pakistani medical schools that require remedy. The Dundee Polyprofessional Inventory-1 as customized for use in Pakistan is a useful tool to measure professionalism lapses related to academic integrity.

  4. TIME-LAPSE MODELING AND INVERSION OF CO2 SATURATION FOR SEQUESTRATION AND ENHANCED OIL RECOVERY

    SciTech Connect

    Mark A. Meadows

    2005-05-25

    In this quarter we have continued our development of the inversion procedure for Phase III, in which time-lapse changes in seismic attributes are inverted to yield changes in CO{sub 2} fluid properties over time. In order to extract seismic attributes from the Sleipner North Sea CO{sub 2} time-lapse data set, a new, detailed interpretation was performed and multiple horizons were picked for the 1994 and 2002 vintages. Traveltime difference maps were constructed at several levels within the Sleipner CO{sub 2} injection zone, and were quantitatively analyzed. No traveltime change was seen in the overburden, as expected, while significant changes were seen in the upper half of the CO{sub 2} injection zone. Evidence of thin-bed tuning and undershooting was also found. A new semi-automated, quantitative method for estimating time sag anomalies was developed, and was used to calculate the amount of time sag along a selected horizon. The resulting time sag estimates matched those seen in the traveltime difference maps. Such a method will be useful for obtaining rapid, accurate quantitative measurements of traveltime changes in the Sleipner data cubes. The traveltime changes will be combined with other attributes, such as amplitude and frequency changes, for input into the real-data inversion.

  5. Using a time lapse microgravity model for mapping seawater intrusion around Semarang

    SciTech Connect

    Supriyadi, Khumaedi; Yusuf, M.; Agung, W.

    2016-03-11

    A modeling of time-lapse microgravity anomaly due to sea water intrusion has been conducted. It used field data of aquifer cross section, aquifer thickness and lithology of research area. Those data were then processed using Grav3D and Surfer. Modeling results indicated that the intrusion of sea water resulting in a time-lapse microgravity anomalies of 0.12 to 0.18 mGal, at soil layer density of 0.15 g/cm{sup 3} to 0.3 g/cm{sup 3} and at depth of 30 to 100 m. These imply that the areas experiencing seawater intrusion were Tanjung Mas, SPBE Bandarharjo, Brass, Old Market Boom and Johar as the microgravity measured there were in the range of 0.12 to 0.18 mGal and the density contrast were at 0.15 g/cm{sup 3} to 0.28 g/cm{sup 3}. Areas that experienced fluid reduction were Puri Anjasmoro, Kenconowungu and Puspowarno with microgravity changes from -0.06 mGal to -0.18 mGal.

  6. A cautionary note against embryo aneuploidy risk assessment using time-lapse imaging.

    PubMed

    Ottolini, Christian; Rienzi, Laura; Capalbo, Antonio

    2014-03-01

    Preimplantation genetic screening (PGS) for embryo aneuploidy using embryo biopsy is a widely available technique used to select embryos for transfer following IVF for certain patient populations. Since its introduction, there has been an ongoing search for a non-invasive technique to perform PGS. Such an advance would revolutionize the field of IVF enabling PGS to be used universally as a routine embryo selection tool with the potential to significantly increase pregnancy rates and decrease poor outcomes such as miscarriage. Recent publications illustrating the development of an algorithm using time-lapse imaging of IVF embryos have claimed to have done just this. We believe that the statements made in these articles, which include the proposed ability to increase pregnancy rates by determining embryo aneuploidy risk by time-lapse imaging, are premature and to this point unsubstantiated by the published data. We provide evidence from existing publications and from our own data that suggests that the statements recently made are misleading. We make the point that further investigation is needed either in the form of a larger, age-adjusted data set or preferably in a randomized controlled trial.

  7. Time-lapse microgravity data acquisition in baseline stage of CO2 injection Gundih pilot project

    NASA Astrophysics Data System (ADS)

    Januari Wahyudi, Eko; Marthen, R.; Fukuda, Y.; Nurali, Y.

    2017-04-01

    Indonesia is conducting research on CO2 sequestration and monitoring in Gundih area. Geophysical methods are applied in the study area as monitoring technologies of CO2 storage in the subsurface. In this paper, we will describe data quality and baseline geophysical survey (2014 and 2016) as part of time-lapse microgravity (TLM) data acquisition. The same set of two relative gravimeters (Scintrex CG5) were used in 2014 and 2016 gravity data acquisition to provide TLM map. TLM can be useful to monitor the mass increase and decrease due to significant activities in the reservoir, but for this project TLM signal (caused by the CO2 injection in Gundih’s reservoir) estimated very small. Considering current project status, no injection yet, the data acquisition in 2014 and 2016 will be analysed to help us understand non-target anomalies in near surface. Preliminary analysis of gravity differences between 2014 and 2016 shows correlation pattern of time-lapse microgravity with land use in the study area. Rice fields and villages in the Western part of the study area correlate with negative TLM anomalies and forest area in the Eastern part of the study area correlate with positive TLM anomalies.

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

    NASA Astrophysics Data System (ADS)

    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

  9. Impaired sustained attention and lapses are present in patients with mild obstructive sleep apnea.

    PubMed

    Luz, Gabriela Pontes; Guimarães, Thais Moura; Weaver, Terri E; Nery, Luiz E; E Silva, Luciana Oliveira; Badke, Luciana; Coelho, Glaury; Millani-Carneiro, Aline; Tufik, Sergio; Bittencourt, Lia

    2016-05-01

    Severe obstructive sleep apnea (OSA) directly affects the quality of life, mood, and sustained attention of individuals, but it has not yet been established in the literature, if these changes also affect patients with mild OSA. The purpose of this study was to investigate such negative effects on the parameters described above. A controlled study was held at the Universidade Federal de Sao Paulo, Department of Psychobiology. Thirty-nine mild OSA patients and 25 controls were included. Volunteers could be of both genders with body mass index (BMI) ≤35 kg/m(2) and age between 18 and 65 years. Both groups were subjected to full-night polysomnography (PSG), the subjective assessment of mood (Beck Inventory of Anxiety and Depression), Functional Outcomes of Sleep Questionnaire (FOSQ), and the psychomotor vigilance task (PVT) five times during the day. We considered mild OSA patients those with apnea-hypopnea index (AHI) score between 5 and 15. The control group included subjects with AHI scores <5, respiratory disturbance index (RDI) scores ≤5, arousal index values ≤15, and Epworth Sleepiness Scale (ESS) values ≤9. Mild OSA patients were older and more obese than the controls. After adjusting for age, BMI, and schooling years, there was an increased number of total lapses (3.90 ± 4.16 and 2.43 ± 5.55, p = 0.004). Patients with mild OSA showed increased sustained attention lapses compared with normal subjects.

  10. 4D reconstruction of soil surface changes with time-lapse cameras

    NASA Astrophysics Data System (ADS)

    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.

  11. Numerical studies of imaging subsurface waterfloods using CSERT with time-lapse inversion

    NASA Astrophysics Data System (ADS)

    Zhang, Ying-Ying; Liu, De-Jun; Wang, Li-Yang; Ai, Qing-Hui; Qin, Min-Jun

    2015-12-01

    During the operation of the waterflooding technique, it is necessary to identify the waterflooding areas to enhance oil displacement efficiency. A casing-surface electrical resistivity tomography (CSERT) system using a well casing as a long electrode is able to detect a wide lateral scope, but its vertical resolution and ability to identify deep anomalies in the reservoir are limited, particularly for reservoirs with high-conductivity anomalies in the shallow subsurface, which disturb the response from the water floods at depth. In this study, we first simplified this kind of reservoir into a dual layered anomaly model. Then the log-inject-log method with time-lapse inversion was proposed and evaluated regarding its ability to improve the imaging of the deep waterflooding areas and the shallow anomaly. The results were compared with the commonly used static measurement with static inversion. In the static inversion results, the shallow anomaly was imaged well but the deep anomaly was unobservable. The results of the proposed log-inject-log method with time-lapse inversion showed that it is able to identify the shallow and deep anomalies better under various conditions, thus validating its ability to improve the vertical resolution of the CSERT system.

  12. Label free high throughput screening for apoptosis inducing chemicals using time-lapse microscopy signal processing.

    PubMed

    Aftab, Obaid; Nazir, Madiha; Fryknäs, Mårten; Hammerling, Ulf; Larsson, Rolf; Gustafsson, Mats G

    2014-09-01

    Label free time-lapse microscopy has opened a new avenue to the study of time evolving events in living cells. When combined with automated image analysis it provides a powerful tool that enables automated large-scale spatiotemporal quantification at the cell population level. Very few attempts, however, have been reported regarding the design of image analysis algorithms dedicated to the detection of apoptotic cells in such time-lapse microscopy images. In particular, none of the reported attempts is based on sufficiently fast signal processing algorithms to enable large-scale detection of apoptosis within hours/days without access to high-end computers. Here we show that it is indeed possible to successfully detect chemically induced apoptosis by applying a two-dimensional linear matched filter tailored to the detection of objects with the typical features of an apoptotic cell in phase-contrast images. First a set of recorded computational detections of apoptosis was validated by comparison with apoptosis specific caspase activity readouts obtained via a fluorescence based assay. Then a large screen encompassing 2,866 drug like compounds was performed using the human colorectal carcinoma cell line HCT116. In addition to many well known inducers (positive controls) the screening resulted in the detection of two compounds here reported for the first time to induce apoptosis.

  13. Fluorescence Time-lapse Imaging of the Complete S. venezuelae Life Cycle Using a Microfluidic Device.

    PubMed

    Schlimpert, Susan; Flärdh, Klas; Buttner, Mark

    2016-02-28

    Live-cell imaging of biological processes at the single cell level has been instrumental to our current understanding of the subcellular organization of bacterial cells. However, the application of time-lapse microscopy to study the cell biological processes underpinning development in the sporulating filamentous bacteria Streptomyces has been hampered by technical difficulties. Here we present a protocol to overcome these limitations by growing the new model species, Streptomyces venezuelae, in a commercially available microfluidic device which is connected to an inverted fluorescence widefield microscope. Unlike the classical model species, Streptomyces coelicolor, S. venezuelae sporulates in liquid, allowing the application of microfluidic growth chambers to cultivate and microscopically monitor the cellular development and differentiation of S. venezuelae over long time periods. In addition to monitoring morphological changes, the spatio-temporal distribution of fluorescently labeled target proteins can also be visualized by time-lapse microscopy. Moreover, the microfluidic platform offers the experimental flexibility to exchange the culture medium, which is used in the detailed protocol to stimulate sporulation of S. venezuelae in the microfluidic chamber. Images of the entire S. venezuelae life cycle are acquired at specific intervals and processed in the open-source software Fiji to produce movies of the recorded time-series.

  14. Very-high-resolution time-lapse photography for plant and ecosystems research.

    PubMed

    Nichols, Mary H; Steven, Janet C; Sargent, Randy; Dille, Paul; Schapiro, Joshua

    2013-09-01

    Traditional photography is a compromise between image detail and area covered. We report a new method for creating time-lapse sequences of very-high-resolution photographs to produce zoomable images that facilitate observation across a range of spatial and temporal scales. • A robotic camera mount and software were used to capture images of the growth and movement in Brassica rapa every 15 s in the laboratory. The resultant time-lapse sequence (http://timemachine.gigapan.org/wiki/Plant_Growth) captures growth detail such as circumnutation. A modified, solar-powered system was deployed at a remote field site in southern Arizona. Images were collected every 2 h over a 3-mo period to capture the response of vegetation to monsoon season rainfall (http://timemachine.gigapan.org/wiki/Arizona_Grasslands). • A technique for observing time sequences of both individual plant and ecosystem response at a range of spatial scales is available for use in the laboratory and in the field.

  15. Very-high-resolution time-lapse photography for plant and ecosystems research1

    PubMed Central

    Nichols, Mary H.; Steven, Janet C.; Sargent, Randy; Dille, Paul; Schapiro, Joshua

    2013-01-01

    • Premise of the study: Traditional photography is a compromise between image detail and area covered. We report a new method for creating time-lapse sequences of very-high-resolution photographs to produce zoomable images that facilitate observation across a range of spatial and temporal scales. • Methods and Results: A robotic camera mount and software were used to capture images of the growth and movement in Brassica rapa every 15 s in the laboratory. The resultant time-lapse sequence (http://timemachine.gigapan.org/wiki/Plant_Growth) captures growth detail such as circumnutation. A modified, solar-powered system was deployed at a remote field site in southern Arizona. Images were collected every 2 h over a 3-mo period to capture the response of vegetation to monsoon season rainfall (http://timemachine.gigapan.org/wiki/Arizona_Grasslands). • Conclusions: A technique for observing time sequences of both individual plant and ecosystem response at a range of spatial scales is available for use in the laboratory and in the field. PMID:25202588

  16. Attentional Lapses in Attention-Deficit/Hyperactivity Disorder: Blank Rather Than Wandering Thoughts.

    PubMed

    Van den Driessche, Charlotte; Bastian, Mikaël; Peyre, Hugo; Stordeur, Coline; Acquaviva, Éric; Bahadori, Sara; Delorme, Richard; Sackur, Jérôme

    2017-10-01

    People with attention-deficit/hyperactivity disorder (ADHD) have difficulties sustaining their attention on external tasks. Such attentional lapses have often been characterized as the simple opposite of external sustained attention, but the different types of attentional lapses, and the subjective experiences to which they correspond, remain unspecified. In this study, we showed that unmedicated children (ages 6-12) with ADHD, when probed during a standard go/no-go task, reported more mind blanking (a mental state characterized by the absence of reportable content) than did control participants. This increase in mind blanking happened at the expense of both focused and wandering thoughts. We also found that methylphenidate reverted the level of mind blanking to baseline (i.e., the level of mind blanking reported by control children without ADHD). However, this restoration led to mind wandering more than to focused attention. In a second experiment, we extended these findings to adults who had subclinical ADHD. These results suggest that executive functions impaired in ADHD are required not only to sustain external attention but also to maintain an internal train of thought.

  17. Coda-wave interferometry analysis of time-lapse VSP data for monitoring geological carbon sequestration

    SciTech Connect

    Zhou, R.; Huang, L.; Rutledge, J.T.; Fehler, M.; Daley, T.M.; Majer, E.L.

    2009-11-01

    Injection and movement/saturation of carbon dioxide (CO2) in a geological formation will cause changes in seismic velocities. We investigate the capability of coda-wave interferometry technique for estimating CO2-induced seismic velocity changes using time-lapse synthetic vertical seismic profiling (VSP) data and the field VSP datasets acquired for monitoring injected CO2 in a brine aquifer in Texas, USA. Synthetic VSP data are calculated using a finite-difference elastic-wave equation scheme and a layered model based on the elastic Marmousi model. A possible leakage scenario is simulated by introducing seismic velocity changes in a layer above the CO2 injection layer. We find that the leakage can be detected by the detection of a difference in seismograms recorded after the injection compared to those recorded before the injection at an earlier time in the seismogram than would be expected if there was no leakage. The absolute values of estimated mean velocity changes, from both synthetic and field VSP data, increase significantly for receiver positions approaching the top of a CO2 reservoir. Our results from field data suggest that the velocity changes caused by CO2 injection could be more than 10% and are consistent with results from a crosswell tomogram study. This study demonstrates that time-lapse VSP with coda-wave interferometry analysis can reliably and effectively monitor geological carbon sequestration.

  18. Time-lapse nanoscopy of friction in the non-Amontons and non-Coulomb regime.

    PubMed

    Ishida, Tadashi; Sato, Takaaki; Ishikawa, Takahiro; Oguma, Masatsugu; Itamura, Noriaki; Goda, Keisuke; Sasaki, Naruo; Fujita, Hiroyuki

    2015-03-11

    Originally discovered by Leonard da Vinci in the 15th century, the force of friction is directly proportional to the applied load (known as Amontons' first law of friction). Furthermore, kinetic friction is independent of the sliding speed (known as Coulomb's law of friction). These empirical laws break down at high normal pressure (due to plastic deformation) and low sliding speed (in the transition regime between static friction and kinetic friction). An important example of this phenomenon is friction between the asperities of tectonic plates on the Earth. Despite its significance, little is known about the detailed mechanism of friction in this regime due to the lack of experimental methods. Here we demonstrate in situ time-lapse nanoscopy of friction between asperities sliding at ultralow speed (∼0.01 nm/s) under high normal pressure (∼GPa). This is made possible by compressing and rubbing a pair of nanometer-scale crystalline silicon anvils with electrostatic microactuators and monitoring its dynamical evolution with a transmission electron microscope. Our analysis of the time-lapse movie indicates that superplastic behavior is induced by decrystallization, plastic deformation, and atomic diffusion at the asperity-asperity interface. The results hold great promise for a better understanding of quasi-static friction under high pressure for geoscience, materials science, and nanotechnology.

  19. Time-lapse electrical resistivity investigations for imaging the grouting injection in shallow subsurface cavities.

    PubMed

    Farooq, Muhammad; Park, Samgyu; Kim, Jung Ho; Song, Young Soo; Amjad Sabir, Mohammad; Umar, Muhammad; Tariq, Mohammad; Muhammad, Said

    2014-01-01

    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.

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

    PubMed Central

    Farooq, Muhammad; Kim, Jung Ho; Song, Young Soo; Amjad Sabir, Mohammad; Umar, Muhammad; Tariq, Mohammad; Muhammad, Said

    2014-01-01

    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. PMID:24578621

  1. Attention lapses in children with spina bifida and hydrocephalus and children with attention-deficit/hyperactivity disorder.

    PubMed

    De la Torre, Gabriel G; Martin, Alba; Cervantes, Elizabeth; Guil, Rocio; Mestre, Jose M

    2017-08-01

    Attentional lapses are usually defined as temporary and often brief shifts of attention away from some primary task to unrelated internal information processing. This study addressed the incidence of attention lapses and differences in attentional functioning in 30 children with attention-deficit/hyperactivity disorder (ADHD), 26 healthy children, and 29 children with spina bifida myelomeningocele and hydrocephalus (SBH). Assessments were conducted using computerized tonic and phasic attention tests, the Symbol Digit Modalities Test (SDMT), and the Trail Making Test Form B (TMT-B). The group with SBH differed from normal controls on cognitive measures of attention and executive functions. The ADHD group obtained lower scores than the SBH group and healthy children. ANOVA results showed that there was an effect of shunt revisions and shunt-related infections on neuropsychological performance. Lapses of attention together with reaction time may thus represent important factors for the understanding of cognitive deficits in SBH.

  2. puffMarker: A Multi-Sensor Approach for Pinpointing the Timing of First Lapse in Smoking Cessation.

    PubMed

    Saleheen, Nazir; Ali, Amin Ahsan; Hossain, Syed Monowar; Sarker, Hillol; Chatterjee, Soujanya; Marlin, Benjamin; Ertin, Emre; al'Absi, Mustafa; Kumar, Santosh

    2015-09-01

    Recent researches have demonstrated the feasibility of detecting smoking from wearable sensors, but their performance on real-life smoking lapse detection is unknown. In this paper, we propose a new model and evaluate its performance on 61 newly abstinent smokers for detecting a first lapse. We use two wearable sensors - breathing pattern from respiration and arm movements from 6-axis inertial sensors worn on wrists. In 10-fold cross-validation on 40 hours of training data from 6 daily smokers, our model achieves a recall rate of 96.9%, for a false positive rate of 1.1%. When our model is applied to 3 days of post-quit data from 32 lapsers, it correctly pinpoints the timing of first lapse in 28 participants. Only 2 false episodes are detected on 20 abstinent days of these participants. When tested on 84 abstinent days from 28 abstainers, the false episode per day is limited to 1/6.

  3. Time-lapse 3D VSP monitoring of a carbon dioxide injection project at Delhi Field, Louisiana

    NASA Astrophysics Data System (ADS)

    Lubis, Muhammad Husni Mubarak

    Delhi Field is a producing oil field located in northeastern Louisiana. The estimated original oil in place (OOIP) is 357 mmbo and approximately 54% of OOIP has been produced through the primary production and water-flooding. A CO2-EOR program has been implemented since November 2009 to recover an additional 17% of OOIP. Reservoir surveillance using time-lapse 3D seismic data has been conducted to monitor the CO2 sweep efficiency. The goal of this study is to monitor the CO2 flow-path in the area around the injector using time-lapse 3D VSP data. For this purpose, two 3D VSPs acquired in June 2010 and again in August 2011 were processed together. Fluid substitution and VSP modeling were performed to understand the influence of pore-fluid saturation change on VSP records. A cross-equalization was performed to improve the similarity of the datasets. This step is important to reduce the ambiguity in time-lapse observation. The splice of a 3D VSP image into the surface seismic data becomes the key point in determining the reflector of the reservoir. By integrating the observation from the modeling and the splice of 3D VSP image to surface seismic, the CO2 flow-path from injector 164-3 can be identified from 3D time-lapse VSP data. The CO2 was not radially distributed around the injector, but moved toward southwest direction. This finding is also consistent with the flow-path interpreted from surface seismic. This consistency implies that time-lapse 3D VSP surveys at Delhi Field confirm and augment the time-lapse interpretation from surface seismic data.

  4. Time-lapse seismic waveform modelling and attribute analysis using hydromechanical models for a deep reservoir undergoing depletion

    NASA Astrophysics Data System (ADS)

    He, Y.-X.; Angus, D. A.; Blanchard, T. D.; Wang, G.-L.; Yuan, S.-Y.; Garcia, A.

    2016-04-01

    Extraction of fluids from subsurface reservoirs induces changes in pore pressure, leading not only to geomechanical changes, but also perturbations in seismic velocities and hence observable seismic attributes. Time-lapse seismic analysis can be used to estimate changes in subsurface hydromechanical properties and thus act as a monitoring tool for geological reservoirs. The ability to observe and quantify changes in fluid, stress and strain using seismic techniques has important implications for monitoring risk not only for petroleum applications but also for geological storage of CO2 and nuclear waste scenarios. In this paper, we integrate hydromechanical simulation results with rock physics models and full-waveform seismic modelling to assess time-lapse seismic attribute resolution for dynamic reservoir characterization and hydromechanical model calibration. The time-lapse seismic simulations use a dynamic elastic reservoir model based on a North Sea deep reservoir undergoing large pressure changes. The time-lapse seismic traveltime shifts and time strains calculated from the modelled and processed synthetic data sets (i.e. pre-stack and post-stack data) are in a reasonable agreement with the true earth models, indicating the feasibility of using 1-D strain rock physics transform and time-lapse seismic processing methodology. Estimated vertical traveltime shifts for the overburden and the majority of the reservoir are within ±1 ms of the true earth model values, indicating that the time-lapse technique is sufficiently accurate for predicting overburden velocity changes and hence geomechanical effects. Characterization of deeper structure below the overburden becomes less accurate, where more advanced time-lapse seismic processing and migration is needed to handle the complex geometry and strong lateral induced velocity changes. Nevertheless, both migrated full-offset pre-stack and near-offset post-stack data image the general features of both the overburden and

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

    USGS Publications Warehouse

    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.

  6. Nonuniversal transmission phase lapses through a quantum dot: an exact diagonalization of the many-body transport problem.

    PubMed

    Baksmaty, Leslie O; Yannouleas, Constantine; Landman, Uzi

    2008-09-26

    Systematic trends of nonuniversal behavior of electron-transmission phases through a quantum dot, with no phase lapse for the transition N = 1-->N = 2 and a lapse of pi for the N = 2-->N = 3 transition, are predicted, in agreement with experiments, from many-body transport calculations involving exact diagonalization of the dot Hamiltonian. The results favor shape anisotropy of the dot and strong e-e repulsion with consequent electron localization, showing dependence on spin configurations and the participation of excited doorway transmission channels.

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

    SciTech Connect

    Huang, Lianjie; Rutledge, James; Cheng, Arthur

    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

  8. Minds “At Attention”: Mindfulness Training Curbs Attentional Lapses in Military Cohorts

    PubMed Central

    Jha, Amishi P.; Morrison, Alexandra B.; Dainer-Best, Justin; Parker, Suzanne; Rostrup, Nina; Stanley, Elizabeth A.

    2015-01-01

    We investigated the impact of mindfulness training (MT) on attentional performance lapses associated with task-unrelated thought (i.e., mind wandering). Periods of persistent and intensive demands may compromise attention and increase off-task thinking. Here, we investigated if MT may mitigate these deleterious effects and promote cognitive resilience in military cohorts enduring a high-demand interval of predeployment training. To better understand which aspects of MT programs are most beneficial, three military cohorts were examined. Two of the three groups were provided MT. One group received an 8-hour, 8-week variant of Mindfulness-based Mind Fitness Training (MMFT) emphasizing engagement in training exercises (training-focused MT, n = 40), a second group received a didactic-focused variant emphasizing content regarding stress and resilience (didactic-focused MT, n = 40), and the third group served as a no-training control (NTC, n = 24). Sustained Attention to Response Task (SART) performance was indexed in all military groups and a no-training civilian group (CIV, n = 45) before (T1) and after (T2) the MT course period. Attentional performance (measured by A’, a sensitivity index) was lower in NTC vs. CIV at T2, suggesting that performance suffers after enduring a high-demand predeployment interval relative to a similar time period of civilian life. Yet, there were significantly fewer performance lapses in the military cohorts receiving MT relative to NTC, with training-focused MT outperforming didactic-focused MT at T2. From T1 to T2, A’ degraded in NTC and didactic-focused MT but remained stable in training-focused MT and CIV. In sum, while protracted periods of high-demand military training may increase attentional performance lapses, practice-focused MT programs akin to training-focused MT may bolster attentional performance more than didactic-focused programs. As such, training-focused MT programs should be further examined in cohorts experiencing

  9. Active and passive electrical and seismic time-lapse monitoring of earthen embankments

    NASA Astrophysics Data System (ADS)

    Rittgers, Justin Bradley

    In this dissertation, I present research involving the application of active and passive geophysical data collection, data assimilation, and inverse modeling for the purpose of earthen embankment infrastructure assessment. Throughout the dissertation, I identify several data characteristics, and several challenges intrinsic to characterization and imaging of earthen embankments and anomalous seepage phenomena, from both a static and time-lapse geophysical monitoring perspective. I begin with the presentation of a field study conducted on a seeping earthen dam, involving static and independent inversions of active tomography data sets, and self-potential modeling of fluid flow within a confined aquifer. Additionally, I present results of active and passive time-lapse geophysical monitoring conducted during two meso-scale laboratory experiments involving the failure and self-healing of embankment filter materials via induced vertical cracking. Identified data signatures and trends, as well as 4D inversion results, are discussed as an underlying motivation for conducting subsequent research. Next, I present a new 4D acoustic emissions source localization algorithm that is applied to passive seismic monitoring data collected during a full-scale embankment failure test. Acoustic emissions localization results are then used to help spatially constrain 4D inversion of collocated self-potential monitoring data. I then turn to time-lapse joint inversion of active tomographic data sets applied to the characterization and monitoring of earthen embankments. Here, I develop a new technique for applying spatiotemporally varying structural joint inversion constraints. The new technique, referred to as Automatic Joint Constraints (AJC), is first demonstrated on a synthetic 2D joint model space, and is then applied to real geophysical monitoring data sets collected during a full-scale earthen embankment piping-failure test. Finally, I discuss some non-technical issues related to

  10. Data pre-processing for time-lapse full waveform inversion: an example from the Ketzin CO2 geological storage site

    NASA Astrophysics Data System (ADS)

    Zhang, Fengjiao; Juhlin, Christopher; Han, Liguo; Huang, Fei; Luth, Stefan

    2017-04-01

    Full waveform inversion is an effective tool for velocity model building. Recently it has been introduced as a complementary method for interpreting time-lapse seismic data as it can be used to detect velocity changes in reservoirs. There are already some successful applications in the fields of oil/gas production and CO2 injection monitoring. We present a case study of data pre-processing of time-lapse data from the Ketzin CO2 geological storage site. Ketzin is a well-known onshore CO2 geological storage pilot site. Due to the restriction of the acquisition geometry, the time-lapse seismic data sets here have limited maximum offset which makes direct inversion for reservoir velocity difficult. As shown by experiences from other case studies, the double difference full waveform inversion method is the best choice here. The success of double difference time-lapse full waveform inversion is highly dependent upon data pre-processing. This is because it only inverts the difference between the baseline and repeat shot gathers. In order to get the correct velocity change in the reservoir, it is important to apply some pre-processing steps to remove the time-lapse noise above the reservoir. In this study we apply cross equalization and time-lapse difference static corrections to remove the time-lapse noise in the shot gathers. We test our methods by using synthetic data sets. The results show that these methods can effectively remove the time-lapse noise in the shot gathers. We also apply these methods to the real time-lapse shot gathers from the Ketzin site. The time-lapse differences above the reservoir time sections are significantly reduced after pre-processing.

  11. Effects of stratospheric lapse rate on numerically simulated thunderstorm cloud top structure

    NASA Technical Reports Server (NTRS)

    Schlesinger, R. E.

    1985-01-01

    The study of overshooting midlatitude severe thunderstorm tops has led to the detection of some intriguing patterns. This paper provides a summary of an investigation of the effects of stratospheric stability on thunderstorm cloud top structure, taking into account the utilization of a fully three-dimensional (3D) anelastic model discussed by Schlesinger (1975, 1978, 1984). The layout of model experiments is discussed, giving attention to initial environmental soundings, and initial forcing. The time variation of the vertical velocity extreme is examined, and a description of the mature storm structure is presented. Constant-altitude plane views throughout storm depth are considered along with cloud top height fields. With the stratospheric lapse, the warm region is small and breaks down into separate spots with secondary cold spots downshear of them.

  12. Effects of stratospheric lapse rate on numerically simulated thunderstorm cloud top structure

    NASA Technical Reports Server (NTRS)

    Schlesinger, Robert E.

    1985-01-01

    The three-dimensional anelastic model of Schlesinger (1975, 1978, 1984) is utilized to study the effects of stratospheric stability on thunderstorm cloud top structure. Three experiments were conducted; in the first the stratosphere is assumed isothermal, in the second test there is a temperature lapse of 3 K/km, and in the third case there is a 3 K/km inversion. Time variations of vertical velocity, mature storm structure, and cloud top are examined. It is observed that the cloud summit height is lowered as stratospheric stability increases, a cloud-top thermal couplet occurs in all cases, the cold region has a U or V shape, and there is a height minimum in the warm regions.

  13. Time-Lapse Electrical Resistivity Monitoring of the Remediation of a Saline Groundwater Plume

    NASA Astrophysics Data System (ADS)

    Hayley, K.; Bentlay, L. R.; Gharibi, M.

    2007-12-01

    Time-lapse electrical resistivity (ER) surveys are used to monitor the movement and remediation of a saline contaminant plume over the span of three years. Temperature is responsible for a large proportion of the observed ER changes. A temperature resistivity relationship is developed through laboratory testing on core from the site and analysis of petrophysical models. We present a protocol for removing the effects of temperature from ER difference images. Saturation changes also contribute to changes in the ER images. However, at this site, saturation is too spatially heterogeneous to apply a simple correction as was done with temperature. We show that the magnitude of the saturation changes are low and present an analysis of the uncertainty this introduces into the image interpretation. After accounting for temperature variations, we observe changes in the subsurface ER distribution that are consistent with depression focused recharge, solute flushing, and spatially variable effectiveness of the remediation program.

  14. Visualizing and quantifying movement from pre-recorded videos: The spectral time-lapse (STL) algorithm.

    PubMed

    Madan, Christopher R; Spetch, Marcia L

    2014-01-01

    When studying animal behaviour within an open environment, movement-related data are often important for behavioural analyses. Therefore, simple and efficient techniques are needed to present and analyze the data of such movements. However, it is challenging to present both spatial and temporal information of movements within a two-dimensional image representation. To address this challenge, we developed the spectral time-lapse (STL) algorithm that re-codes an animal's position at every time point with a time-specific color, and overlays it with a reference frame of the video, to produce a summary image. We additionally incorporated automated motion tracking, such that the animal's position can be extracted and summary statistics such as path length and duration can be calculated, as well as instantaneous velocity and acceleration. Here we describe the STL algorithm and offer a freely available MATLAB toolbox that implements the algorithm and allows for a large degree of end-user control and flexibility.

  15. Patenting medical diagnosis methods in Europe: Stanford University and time-lapse microscopy.

    PubMed

    Sterckx, Sigrid; Cockbain, Julian; Pennings, Guido

    2017-02-01

    In 2013, a European Patent for the technique of time-lapse microscopy was granted by the European Patent Office (EPO) to Stanford University and was subsequently opposed by Unisense FertiliTech A/S and by the European Society for Human Reproduction and Embryology (ESHRE), Sigrid Sterckx, Julian Cockbain and Guido Pennings. ESHRE et al.'s opposition was based on the argument that Stanford's patent was directed to a method of medical diagnosis, methods that are excluded from patentability by Article 53(c) of the European Patent Convention. The Opposition Division of the EPO rejected the oppositions in November 2015, and both opponents have now filed their appeals. In this paper, we comment on the Opposition Division decision and the grounds of appeal put forward by ESHRE et al.

  16. In vivo amyloid aggregation kinetics tracked by time-lapse confocal microscopy in real-time.

    PubMed

    Villar-Piqué, Anna; Espargaró, Alba; Ventura, Salvador; Sabate, Raimon

    2016-01-01

    Amyloid polymerization underlies an increasing number of human diseases. Despite this process having been studied extensively in vitro, aggregation is a difficult process to track in vivo due to methodological limitations and the slow kinetics of aggregation reactions in cells and tissues. Herein we exploit the amyloid properties of the inclusions bodies (IBs) formed by amyloidogenic proteins in bacteria to address the kinetics of in vivo amyloid aggregation. To this aim we used time-lapse confocal microscopy and a fusion of the amyloid-beta peptide (A β42) with a fluorescent reporter. This strategy allowed us to follow the intracellular kinetics of amyloid-like aggregation in real-time and to discriminate between variants exhibiting different in vivo aggregation propensity. Overall, the approach opens the possibility to assess the impact of point mutations as well as potential anti-aggregation drugs in the process of amyloid formation in living cells.

  17. TRIIG - Time-lapse reproduction of images through interactive graphics. [digital processing of quality hard copy

    NASA Technical Reports Server (NTRS)

    Buckner, J. D.; Council, H. W.; Edwards, T. R.

    1974-01-01

    Description of the hardware and software implementing the system of time-lapse reproduction of images through interactive graphics (TRIIG). The system produces a quality hard copy of processed images in a fast and inexpensive manner. This capability allows for optimal development of processing software through the rapid viewing of many image frames in an interactive mode. Three critical optical devices are used to reproduce an image: an Optronics photo reader/writer, the Adage Graphics Terminal, and Polaroid Type 57 high speed film. Typical sources of digitized images are observation satellites, such as ERTS or Mariner, computer coupled electron microscopes for high-magnification studies, or computer coupled X-ray devices for medical research.

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

    PubMed

    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.

  19. Time-lapse cinematography of dynamic changes occurring during in vitro development of human embryos.

    PubMed

    Mio, Yasuyuki; Maeda, Kazuo

    2008-12-01

    The purpose of this study was to clarify developmental changes of early human embryos by using time-lapse cinematography (TLC). For human ova, fertilization and cleavage, development of the blastocyst, and hatching, as well as consequent changes were repeatedly photographed at intervals of 5-6 days by using an inverse microscope under stabilized temperature and pH. Photographs were taken at 30 frames per second and the movies were studied. Cinematography has increased our understanding of the morphologic mechanisms of fertilization, development, and behavior of early human embryos, and has identified the increased risk of monozygotic twin pregnancy based on prolonged incubation in vitro to the blastocyst stage. Using TLC, we observed the fertilization of an ovum by a single spermatozoon, followed by early cleavages, formation of the morula, blastocyst hatching, changes in the embryonic plates, and the development of monozygotic twins from the incubated blastocysts.

  20. A poly(dimethylsiloxane)-based device enabling time-lapse imaging with high spatial resolution

    SciTech Connect

    Hirano, Masahiko; Hoshida, Tetsushi; Sakaue-Sawano, Asako; Miyawaki, Atsushi

    2010-02-12

    We have developed a regulator-free device that enables long-term incubation of mammalian cells for epi-fluorescence imaging, based on a concept that the size of sample to be gassed and heated is reduced to observation scale. A poly(dimethylsiloxane) block stamped on a coverslip works as a long-lasting supplier of CO{sub 2}-rich gas to adjust bicarbonate-containing medium in a tiny chamber at physiological pH, and an oil-immersion objective warms cells across the coverslip. A time-lapse imaging experiment using HeLa cells stably expressing fluorescent cell-cycle indicators showed that the cells in the chamber proliferated with normal cell-cycle period over 2 days.

  1. Time-lapse cinematography of the capillary tube cell migration inhibition test.

    PubMed

    Bray, M A

    1980-01-01

    The kinetics of human and guinea pig cell migration inhibition have been studied using time-lapse cinematography of cells migrating from capillary tubes. Guinea pig and human cells exhibit markedly different kinetics in the absence of inhibitors. Specific antigen causes a dose-related inhibition of migration for up to 60 h using guinea pig cells and a peak of inhibition after 18 h using the human leucocyte system. The timing of measurement of maximum activity more critical for the latter test. The kinetics of lymphokine generation have been examined and the migration inhibitory activity of the plant mitogen (PHA), a Kurloff cell product and a continuous cell line supernatant have been compared with the inhibitory profiles of lymphokine preparations and specific antigen.

  2. Time-lapse cinematography in living Drosophila tissues: preparation of material.

    PubMed

    Davis, Ilan; Parton, Richard M

    2006-11-01

    The fruit fly, Drosophila melanogaster, has been an extraordinarily successful model organism for studying the genetic basis of development and evolution. It is arguably the best-understood complex multicellular model system, owing its success to many factors. Recent developments in imaging techniques, in particular sophisticated fluorescence microscopy methods and equipment, now allow cellular events to be studied at high resolution in living material. This ability has enabled the study of features that tend to be lost or damaged by fixation, such as transient or dynamic events. Although many of the techniques of live cell imaging in Drosophila are shared with the greater community of cell biologists working on other model systems, studying living fly tissues presents unique difficulties in keeping the cells alive, introducing fluorescent probes, and imaging through thick hazy cytoplasm. This protocol outlines the preparation of major tissue types amenable to study by time-lapse cinematography and different methods for keeping them alive.

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

    PubMed

    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.

  4. Electron microscopic time-lapse visualization of surface pore filtration on particulate matter trapping process.

    PubMed

    Sanui, Ryoko; Hanamura, Katsunori

    2016-09-01

    A scanning electron microscope (SEM) was used to dynamically visualize the particulate matter (PM) trapping process on diesel particulate filter (DPF) walls at a micro scale as 'time-lapse' images corresponding to the increase in pressure drop simultaneously measured through the DPF. This visualization and pressure drop measurement led to the conclusion that the PM trapping in surface pores was driven by PM bridging and stacking at constricted areas in porous channels. This caused a drastic increase in the pressure drop during PM accumulation at the beginning of the PM trapping process. The relationship between the porous structure of the DPF and the depth of the surface pore was investigated in terms of the porosity distribution and PM penetration depth near the wall surface with respect to depth. The pressure drop calculated with an assumed surface pore depth showed a good correspondence to the measured pressure drop.

  5. Time-lapse geophysical investigations over a simulated urban clandestine grave.

    PubMed

    Pringle, Jamie K; Jervis, John; Cassella, John P; Cassidy, Nigel J

    2008-11-01

    A simulated clandestine shallow grave was created within a heterogeneous, made-ground, urban environment where a clothed, plastic resin, human skeleton, animal products, and physiological saline were placed in anatomically correct positions and re-covered to ground level. A series of repeat (time-lapse), near-surface geophysical surveys were undertaken: (1) prior to burial (to act as control), (2) 1 month, and (3) 3 months post-burial. A range of different geophysical techniques was employed including: bulk ground resistivity and conductivity, fluxgate gradiometry and high-frequency ground penetrating radar (GPR), soil magnetic susceptibility, electrical resistivity tomography (ERT), and self potential (SP). Bulk ground resistivity and SP proved optimal for initial grave location whilst ERT profiles and GPR horizontal "time-slices" showed the best spatial resolutions. Research suggests that in complex urban made-ground environments, initial resistivity surveys be collected before GPR and ERT follow-up surveys are collected over the identified geophysical anomalies.

  6. Wavelet compression of three-dimensional time-lapse biological image data.

    PubMed

    Stefansson, H Narfi; Eliceiri, Kevin W; Thomas, Charles F; Ron, Amos; DeVore, Ron; Sharpley, Robert; White, John G

    2005-02-01

    The use of multifocal-plane, time-lapse recordings of living specimens has allowed investigators to visualize dynamic events both within ensembles of cells and individual cells. Recordings of such four-dimensional (4D) data from digital optical sectioning microscopy produce very large data sets. We describe a wavelet-based data compression algorithm that capitalizes on the inherent redunancies within multidimensional data to achieve higher compression levels than can be obtained from single images. The algorithm will permit remote users to roam through large 4D data sets using communication channels of modest bandwidth at high speed. This will allow animation to be used as a powerful aid to visualizing dynamic changes in three-dimensional structures.

  7. Time-Lapse Video of SLS Engine Section Test Article Being Stacked at Michoud

    NASA Image and Video Library

    2017-04-25

    This time-lapse video shows the Space Launch System engine section structural qualification test article being stacked at NASA's Michoud Assembly Facility in New Orleans. The rocket's engine section is the bottom of the core stage and houses the four RS-25 engines. The engine section test article was moved to Michoud's Cell A in Building 110 for vertical stacking with hardware that simulates the rocket's liquid hydrogen tank, which is the fuel tank that joins to the engine section. Once stacked, the entire test article will load onto the barge Pegasus and ship to NASA's Marshall Space Flight Center in Huntsville, Alabama. There, it will be subjected to millions of pounds of force during testing to ensure the hardware can withstand the incredible stresses of launch.

  8. Cell invasion with proliferation mechanisms motivated by time-lapse data

    NASA Astrophysics Data System (ADS)

    Simpson, Matthew J.; Landman, Kerry A.; Hughes, Barry D.

    2010-09-01

    Cell invasion involves a population of cells which are motile and proliferative. Traditional discrete models of proliferation involve agents depositing daughter agents on nearest-neighbor lattice sites. Motivated by time-lapse images of cell invasion, we propose and analyze two new discrete proliferation models in the context of an exclusion process with an undirected motility mechanism. These discrete models are related to a family of reaction-diffusion equations and can be used to make predictions over a range of scales appropriate for interpreting experimental data. The new proliferation mechanisms are biologically relevant and mathematically convenient as the continuum-discrete relationship is more robust for the new proliferation mechanisms relative to traditional approaches.

  9. Motivations for Giving of Alumni Donors, Lapsed Donors and Non-Donors: Implications for Christian Higher Education

    ERIC Educational Resources Information Center

    Rugano, Emilio Kariuki

    2011-01-01

    This descriptive and causal comparative study sought to identify motivations for alumni donor acquisition and retention in Christian institutions of higher learning. To meet this objective, motivations for alumni donors, lapsed donors, and non-donors were analyzed and compared. Data was collected through an electronic survey of a stratified sample…

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

    EPA Science Inventory

    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...

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

    NASA Astrophysics Data System (ADS)

    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.

  12. Contribution of 3-D time-lapse ERT to the study of leachate recirculation in a landfill

    SciTech Connect

    Clement, R.; Oxarango, L.; Descloitres, M.

    2011-03-15

    Leachate recirculation is a key process in the operation of municipal waste landfills as bioreactors. It aims at increasing the moisture content to optimise the biodegradation. Because waste is a very heterogeneous and anisotropic porous media, the geometry of the leachate plume recirculation is difficult to delineate from the surface at the scale of the bioreactor site. In this study, 3-D time-lapse electrical resistivity tomography (ERT) was used to obtain useful information for understanding leachate recirculation hydrodynamics. The ERT inversion methodology and the electrode arrays were optimised using numerical modelling simulating a 3-D leachate injection scenario. Time-lapse ERT was subsequently applied at the field scale during an experimental injection. We compared ERT images with injected volumes to evaluate the sensitivity of time-lapse ERT to delineate the plume migration. The results show that time-lapse ERT can accomplish the following: (i) accurately locate the injection plume, delineating its depth and lateral extension; (ii) be used to estimate some hydraulic properties of waste.

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

    EPA Science Inventory

    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...

  14. The use of time lapse photography in an in vitro fertilization programme for better selection for embryo transfer.

    PubMed

    Kovačič, Borut; Hojnik, Nina; Vlaisavljević, Veljko

    2014-01-01

    The time lapse photography is not a new method for assessing the dynamics of early embryo development in vitro. It has been used many times in the past for studying cleavages and blastulation of embryos of various animal species. However, this technique became available for routine use in an human in vitro fertilization (IVF) programme only a couple years ago and it becomes more and more popular today. The new time lapse systems are using modified microscopes which are positioned within the incubators. The observation of embryos does not need the opening of incubators. By sequential photographing of each embryo separately with camera of low intensity illumination, more than 1400 pictures of embryo are made. All these pictures are collected together and transformed into a short movie with software. This system offers the observation of dynamics of embryo development. The studies, which have used a time lapse technique for studying embryo development, revealed that the timing between different events can be used for predicting its developmental potential. In this paper the advantages and drawbacks of time lapse photography is precisely described. An overview through the published papers analyzing the dynamics of human embryo development from the zygote toward blastocyst is done and new timing parameters for grading zygotes, early embryos and blastocysts are analyzed.

  15. Motivations for Giving of Alumni Donors, Lapsed Donors and Non-Donors: Implications for Christian Higher Education

    ERIC Educational Resources Information Center

    Rugano, Emilio Kariuki

    2011-01-01

    This descriptive and causal comparative study sought to identify motivations for alumni donor acquisition and retention in Christian institutions of higher learning. To meet this objective, motivations for alumni donors, lapsed donors, and non-donors were analyzed and compared. Data was collected through an electronic survey of a stratified sample…

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Localized time-lapse elastic waveform inversion using wavefield injection and extrapolation: 2-D parametric studies

    NASA Astrophysics Data System (ADS)

    Yuan, Shihao; Fuji, Nobuaki; Singh, Satish; Borisov, Dmitry

    2017-06-01

    We present a methodology to invert seismic data for a localized area by combining source-side wavefield injection and receiver-side extrapolation method. Despite the high resolving power of seismic full waveform inversion, the computational cost for practical scale elastic or viscoelastic waveform inversion remains a heavy burden. This can be much more severe for time-lapse surveys, which require real-time seismic imaging on a daily or weekly basis. Besides, changes of the structure during time-lapse surveys are likely to occur in a small area rather than the whole region of seismic experiments, such as oil and gas reservoir or CO2 injection wells. We thus propose an approach that allows to image effectively and quantitatively the localized structure changes far deep from both source and receiver arrays. In our method, we perform both forward and back propagation only inside the target region. First, we look for the equivalent source expression enclosing the region of interest by using the wavefield injection method. Second, we extrapolate wavefield from physical receivers located near the Earth's surface or on the ocean bottom to an array of virtual receivers in the subsurface by using correlation-type representation theorem. In this study, we present various 2-D elastic numerical examples of the proposed method and quantitatively evaluate errors in obtained models, in comparison to those of conventional full-model inversions. The results show that the proposed localized waveform inversion is not only efficient and robust but also accurate even under the existence of errors in both initial models and observed data.

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

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Astrophysics Data System (ADS)

    Elliott, E. Judith; Braun, Alexander

    2017-08-01

    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.

  20. Improving time-lapse seismic repeatability: CO2CRC Otway site permanent geophone array field trials

    NASA Astrophysics Data System (ADS)

    Pevzner, Roman; Dupuis, Christian; Shulakova, Valeriya; Urosevic, Milovan; Lumley, David

    2013-04-01

    The proposed Stage 2C of the CO2CRC Otway project involves injection of a small amount (around 15,000 tonnes) of CO2/CH4 gas mixture into saline acquifer (Paaratte formation) at the depth of ~1.5 km. The seismic time-lapse signal will depend largely on the formation properties and the injection scenario, but is likely to be relatively weak. In order to improve time-lapse seismic monitoring capabilities by decreasing the noise level, a buried receiver arrays can be used. A small-scale trial of such an array was conducted at Otway site in June 2012. A set of 25 geophones was installed in 3 m deep boreholes in parallel to the same number of surface geophones. In addition, four geophones were placed into boreholes of 1 to 12 m depth. In order to assess the gain in the signal-to-noise ratio and repeatability, both active and passive seismic surveys were carried out. The surveys were conducted in relatively poor weather conditions, with rain, strong wind and thunderstorms increasing the noise level. We found that noise level for buried geophones is on average 20 dB lower compared to the surface ones. Furthermore, the combination of active and passive experiments has allowed us to perform a detailed classification of various noise sources. Acknowledgement The authors acknowledge the funding provided by the Australian government through its CRC program to support this CO2CRC research project. We also acknowledge the CO2CRC's corporate sponsors and the financial assistance provided through Australian National Low Emissions Coal Research and Development (ANLEC R&D). ANLEC R&D is supported by Australian Coal Association Low Emissions Technology Limited and the Australian Government through the Clean Energy Initiative.

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

    NASA Astrophysics Data System (ADS)

    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.

  2. Low-cost motility tracking system (LOCOMOTIS) for time-lapse microscopy applications and cell visualisation.

    PubMed

    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.

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

    PubMed Central

    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. Live Cell Imaging of Bacillus subtilis and Streptococcus pneumoniae using Automated Time-lapse Microscopy

    PubMed Central

    de Jong, Imke G.; Beilharz, Katrin; Kuipers, Oscar P.; Veening, Jan- Willem

    2011-01-01

    During the last few years scientists became increasingly aware that average data obtained from microbial population based experiments are not representative of the behavior, status or phenotype of single cells. Due to this new insight the number of single cell studies rises continuously (for recent reviews see 1,2,3). However, many of the single cell techniques applied do not allow monitoring the development and behavior of one specific single cell in time (e.g. flow cytometry or standard microscopy). Here, we provide a detailed description of a microscopy method used in several recent studies 4, 5, 6, 7, which allows following and recording (fluorescence of) individual bacterial cells of Bacillus subtilis and Streptococcus pneumoniae through growth and division for many generations. The resulting movies can be used to construct phylogenetic lineage trees by tracing back the history of a single cell within a population that originated from one common ancestor. This time-lapse fluorescence microscopy method cannot only be used to investigate growth, division and differentiation of individual cells, but also to analyze the effect of cell history and ancestry on specific cellular behavior. Furthermore, time-lapse microscopy is ideally suited to examine gene expression dynamics and protein localization during the bacterial cell cycle. The method explains how to prepare the bacterial cells and construct the microscope slide to enable the outgrowth of single cells into a microcolony. In short, single cells are spotted on a semi-solid surface consisting of growth medium supplemented with agarose on which they grow and divide under a fluorescence microscope within a temperature controlled environmental chamber. Images are captured at specific intervals and are later analyzed using the open source software ImageJ. PMID:21841760

  5. Spatial patterns of climatological temperature lapse rate in mainland China: A multi-time scale investigation

    NASA Astrophysics Data System (ADS)

    Li, Yue; Zeng, Zhenzhong; Zhao, Lin; Piao, Shilong

    2015-04-01

    Quantitative evaluation of how mountain ecosystems respond to climate change requires accurate estimates of temperature at high elevations. One approach to estimating highland temperature is to extrapolate temperatures from low elevations based on previous observations of the environmental temperature lapse rate (γlocal). However, our understanding of γlocal is still very limited. Here we use daily mean, maximum, and minimum temperature (Tmean, Tmax, and Tmin) data from 523 meteorological stations in mainland China to estimate the spatiotemporal patterns of the climatological γlocal (γlocal(Tmean), γlocal(Tmax), and γlocal(Tmin)). The patterns of all γlocal display (1) a significant (P < 0.05) spatial difference between southern China (4 to 6 K km-1) and northern China (including the Qinghai-Tibetan Plateau, >6 K km-1) and (2) a distinct seasonal variation, with higher γlocal occurring in summer and lower in winter (except for the Qinghai-Tibetan Plateau where the seasonality is reversed). In addition, the seasonal amplitude of γlocal(Tmax) exceeds that of γlocal(Tmin). Physically, γlocal(Tmax) is significantly influenced by cloud cover (partial correlation coefficients: R = -0.25, P < 0.001) and regulated by precipitation, with γlocal (Tmax) increasing with Tmax in humid regions while decreasing in drier regions. At night, the spatial pattern of γlocal (Tmin) is determined by Tmin (R = -0.51, P < 0.001) due to temperature control on the saturated adiabatic lapse rate. Our results demonstrate that the magnitude of γlocal obviously differs in regional distributions and seasonal variations and may be a result of the interactions among the climatic factors. To improve the accuracy of the extrapolation method requires spatial patterns of γlocal rather than just a constant universal value.

  6. Gliding Motility of Babesia bovis Merozoites Visualized by Time-Lapse Video Microscopy

    PubMed Central

    Asada, Masahito; Goto, Yasuyuki; Yahata, Kazuhide; Yokoyama, Naoaki; Kawai, Satoru; Inoue, Noboru; Kaneko, Osamu; Kawazu, Shin-ichiro

    2012-01-01

    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. PMID:22506073

  7. Time-Lapse Imaging of Red Blood Cell Invasion by the Rodent Malaria Parasite Plasmodium yoelii

    PubMed Central

    Yahata, Kazuhide; Treeck, Moritz; Culleton, Richard; Gilberger, Tim-Wolf; Kaneko, Osamu

    2012-01-01

    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. PMID:23227208

  8. Time-lapse microscopy and image analysis in basic and clinical embryo development research.

    PubMed

    Wong, C; Chen, A A; Behr, B; Shen, S

    2013-02-01

    Mammalian preimplantation embryo development is a complex process in which the exact timing and sequence of events are as essential as the accurate execution of the events themselves. Time-lapse microscopy (TLM) is an ideal tool to study this process since the ability to capture images over time provides a combination of morphological, dynamic and quantitative information about developmental events. Here, we systematically review the application of TLM in basic and clinical embryo research. We identified all relevant preimplantation embryo TLM studies published in English up to May 2012 using PubMed and Google Scholar. We then analysed the technical challenges involved in embryo TLM studies and how these challenges may be overcome with technological innovations. Finally, we reviewed the different types of TLM embryo studies, with a special focus on how TLM can benefit clinical assisted reproduction. Although new parameters predictive of embryo development potential may be discovered and used clinically to potentially increase the success rate of IVF, adopting TLM to routine clinical practice will require innovations in both optics and image analysis. Combined with such innovations, TLM may provide embryologists and clinicians with an important tool for making critical decisions in assisted reproduction. In this review, we perform a literature search of all published early embryo development studies that used time-lapse microscopy (TLM). From the literature, we discuss the benefits of TLM over traditional time-point analysis, as well as the technical difficulties and solutions involved in implementing TLM for embryo studies. We further discuss research that has successfully derived non-invasive markers that may increase the success rate of assisted reproductive technologies, primarily IVF. Most notably, we extend our discussion to highlight important considerations for the practical use of TLM in research and clinical settings.

  9. Assessment of Saturation Patterns on Agricultural Land Using Time-lapse Photography

    NASA Astrophysics Data System (ADS)

    Silasari, R.; Bloeschl, G.

    2015-12-01

    Agricultural land generates overland flow differently from natural environment due to features from anthropogenic activities such as cultivated soil layer and tile drain pipe. During rainfall events, the formation of overland flow may happen from infiltration excess and/or saturation excess according to the threshold processes which are influenced by rainfall characteristics and soil hydraulic parameters. The dynamics of threshold processes in varying rainfall and soil hydraulic conditions will affect the surface runoff response which can be inversely analyzed by visually observing the generated saturation patterns. This study aims to explore the use of time-lapse photographs of saturated plot during rainfall events to observe and understand the threshold processes of overland flow generation. The observation was conducted at Hydrological Open Air Laboratory (HOAL) in Lower Austria with a 2 megapixels surveillance camera overlooking a 1.8 ha tile-drained agricultural field situated on a hillslope. The main tile drain pipe extends from the higher ground into the riparian area - creating a depression line which generates the main saturation track. The time-lapse photographs are able to capture the spatial and temporal dynamics of 0.1 ha saturated plot (117 m long and 10 m wide in average) during three big rainfall events in 2014 which produced measurable overland flow. The photographs also manage to capture the behavior of overland flow on tractor tracks which were generated faster than on the main saturated plot - due to the more compacted soil - and contribute significantly to the overall overland flow discharge and movements. Comparison of the photographs with on-field manual plotting shows good accuracy of the captured saturation plot and the possibility of calculating the plot area digitally. This method gives opportunity to observe overland flow generation on visual basis as a complement of the customary discharge measurements.

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

    PubMed

    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.

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

    PubMed

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

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    Nichols, M. H.; Nearing, M.; Hernandez, M.; Polyakov, V. O.

    2016-07-01

    Gullies that terminate at a vertical-wall are ubiquitous throughout arid and semiarid regions. Multi-year assessments of gully evolution and headcut advance are typically accomplished using traditional ground surveys and aerial photographs, with much recent research focused on integrating data collected at very high spatial resolutions using new techniques such as aerial surveys with blimps or kites and ground surveys with LiDar scanners. However, knowledge of specific processes that drive headcut advance is limited due to inadequate observation and documentation of flash floods and subsequent erosion that can occur at temporal resolutions not captured through repeat surveys. This paper presents a method for using very-high temporal resolution ground-based time-lapse photography to capture short-duration flash floods and gully head evolution in response. In 2004, a base level controlling concrete weir was removed from the outlet of a 1.29 ha semiarid headwater drainage on the Walnut Gulch Experimental Watershed in southeastern Arizona, USA. During the ten year period from 2004 to 2014 the headcut migrated upchannel a total of 14.5 m reducing the contributing area at the headwall by 9.5%. Beginning in July 2012, time-lapse photography was employed to observe event scale channel evolution dynamics. The most frequent erosion processes observed during three seasons of time-lapse photography were plunge pool erosion and mass wasting through sidewall or channel headwall slumping that occurred during summer months. Geomorphic change during the ten year period was dominated by a single piping event in August 2014 that advanced the channel head 7.4 m (51% of the overall advance) and removed 11.3 m3 of sediment. High temporal resolution time-lapse photography was critical for identifying subsurface erosion processes, in the absence of time-lapse images piping would not have been identified as an erosion mechanism responsible for advancing the gully headwall at this site.

  14. Perspective: the education community must develop best practices informed by evidence-based research to remediate lapses of professionalism.

    PubMed

    Papadakis, Maxine A; Paauw, Douglas S; Hafferty, Frederic W; Shapiro, Jo; Byyny, Richard L

    2012-12-01

    In July 2011, the Alpha Omega Alpha Honor Medical Society sponsored a think tank of experts in the field of medical professionalism to focus on interventions and remediation strategies for those-medical students, residents, faculty, and practicing physicians-who demonstrate lapses in professional performance, particularly if the lapses are repeated. Several participants have produced scholarly work on the assessment of professionalism. However, assessment has a limited purpose unless it leads to improvements at both the organizational and individual levels. The field of professionalism has matured enough to recognize that one of the contemporary issues within the self-regulation framework is the task of remediation. Yet there is a paucity of evidence to inform best practices to help those who have lapses. Ultimately, the most effective response to an individual's lapse in professionalism may not be simply to gather knowledge about remedial practices but also to understand organizational responses to the information about such practices already possessed by the institution.The authors report the think tank participants' recommendations on (1) how to use existing data on professionalism remediation and (2) what new evidence is needed to advance approaches to remediation of professional performance. Participants also recommended that the education community can focus on interventions and remediation by (1) performing studies about improving medical professionalism when lapses occur, (2) identifying best evidence-based remediation practices, (3) widely disseminating those practices, and (4) moving over time from a best-practices approach to remediation (which does not yet exist) to a best-evidence model.

  15. CO2 storage in Otway, Australia: influence of geological and reservoir parameters on time-lapse seismic signal modeling

    NASA Astrophysics Data System (ADS)

    Gendrin, A.; Bouquet, S.; Urosevic, M.; Bernth, H.; Kostov, C.; Wisman, P.; Labregere, D.; Verliac, M.

    2009-04-01

    Until now, time lapse seismic signal is mostly used qualitatively in CO2 storage projects, to map the extent of the CO2 plume. Ultimately, we want to use it quantitatively to calculate the amount of injected CO2. This will allow us to check that all the CO2 injected is properly stored and that no leakage is occurring. CO2 injection started in Otway, Australia, in March 2008. Over two years, 100,000 tons of CO2 should be injected in this depleted methane reservoir. This project is very challenging since the injected CO2 mixes with residual methane, which generates a weak time-lapse seismic signature. However, a wealth of information is available: logs, a static model, a calibrated reservoir model, and a rock physics model based on core measurements, which are fundamental for the project. We use 3D finite difference modeling to simulate the expected time-lapse seismic signal. Our initial velocity model is built with logs and seismic interpretation. The rock physics approach is used on the outputs of the reservoir simulation to generate a velocity model after injection. Seismic simulation is then run before and after injection, which provides the theoretical time-lapse seismic signal. Several parameters are poorly constrained in the workflow, which affect time-lapse signal prediction. Porosity and permeability grids are constrained at the wells and are statistically distributed throughout the volume. Relative permeability, capillary pressure, hysteresis, have been measured, for CO2, on a few samples only throughout the world. In this work, we explore the influence of uncertainty on these parameters, and derive an error bar on the estimate of the amount of CO2 stored.

  16. A Submerged Filter Paper Sandwich for Long-term Ex Ovo Time-lapse Imaging of Early Chick Embryos.

    PubMed

    Schmitz, Manuel; Nelemans, Ben K A; Smit, Theodoor H

    2016-12-28

    Due to its availability, low cost, flat geometry, and transparency, the ex ovo chick embryo has become a major vertebrate animal model for the study of morphogenetic events, such as gastrulation(2), neurulation(3)(-)(5), somitogenesis(6), heart bending(7,8), and brain formation(9)(-)(13), during early embryogenesis. Key to understanding morphogenetic processes is to follow them dynamically by time-lapse imaging. The acquisition of time-lapse movies of chick embryogenesis ex ovo has been limited either to short time windows or to the need for an incubator to control temperature and humidity around the embryo(14). Here, we present a new technique to culture chick embryos ex ovo for high-resolution time-lapse imaging using transmitted light microscopy. The submerged filter paper sandwich is a variant of the well-established filter paper carrier technique (EC-culture)(1) and allows for the culturing of chick embryos without the need for a climate chamber. The embryo is sandwiched between two identical filter paper carriers and is kept fully submerged in a simple, temperature-controlled medium covered by a layer of light mineral oil. Starting from the primitive streak stage (Hamburger-Hamilton stage 5, HH5)(15) up to at least the 28-somite stage (HH16)(15), embryos can be cultured with either their ventral or dorsal side up. This allows the acquisition of time-lapse movies covering about 30 hr of embryonic development. Representative time-lapse frames and movies are shown. Embryos are compared morphologically to an embryo cultured in the standard EC-culture. The submerged filter paper sandwich provides a stable environment to study early dorsal and ventral morphogenetic processes. It also allows for live fluorescence imaging and micromanipulations, such as microsurgery, bead implantation, microinjection, gene silencing, and electroporation, and has a strong potential to be combined with immersion objectives for laser-based imaging (including light-sheet microscopy).

  17. A Submerged Filter Paper Sandwich for Long-term Ex Ovo Time-lapse Imaging of Early Chick Embryos

    PubMed Central

    Smit, Theodoor H.

    2016-01-01

    Due to its availability, low cost, flat geometry, and transparency, the ex ovo chick embryo has become a major vertebrate animal model for the study of morphogenetic events, such as gastrulation2, neurulation3-5, somitogenesis6, heart bending7,8, and brain formation9-13, during early embryogenesis. Key to understanding morphogenetic processes is to follow them dynamically by time-lapse imaging. The acquisition of time-lapse movies of chick embryogenesis ex ovo has been limited either to short time windows or to the need for an incubator to control temperature and humidity around the embryo14. Here, we present a new technique to culture chick embryos ex ovo for high-resolution time-lapse imaging using transmitted light microscopy. The submerged filter paper sandwich is a variant of the well-established filter paper carrier technique (EC-culture)1 and allows for the culturing of chick embryos without the need for a climate chamber. The embryo is sandwiched between two identical filter paper carriers and is kept fully submerged in a simple, temperature-controlled medium covered by a layer of light mineral oil. Starting from the primitive streak stage (Hamburger-Hamilton stage 5, HH5)15 up to at least the 28-somite stage (HH16)15, embryos can be cultured with either their ventral or dorsal side up. This allows the acquisition of time-lapse movies covering about 30 hr of embryonic development. Representative time-lapse frames and movies are shown. Embryos are compared morphologically to an embryo cultured in the standard EC-culture. The submerged filter paper sandwich provides a stable environment to study early dorsal and ventral morphogenetic processes. It also allows for live fluorescence imaging and micromanipulations, such as microsurgery, bead implantation, microinjection, gene silencing, and electroporation, and has a strong potential to be combined with immersion objectives for laser-based imaging (including light-sheet microscopy). PMID:28060338

  18. Breath Holding Duration and Self-Reported Smoking Abstinence Intolerance as Predictors of Smoking Lapse Behavior in a Laboratory Analog Task

    PubMed Central

    2013-01-01

    Introduction: Distress intolerance (DI) is elevated in smokers and confers increased risk for relapse following a quit attempt. Intolerance of respiratory distress and of nicotine withdrawal may be particularly relevant predictors of smoking cessation outcomes. However, no studies to date have examined the association between smoking relevant DI and smoking lapse behavior in a laboratory setting. The current study examined whether DI was associated with the risk of initiating smoking in a laboratory-based lapse analog task. Methods: This study is a secondary data analysis from a study of the impact of alcohol administration on smoking behavior. Ninety-six cigarette smokers completed measures of DI and a smoking lapse analog task. Breath holding (BH) duration and self-reported intolerance of smoking abstinence were analyzed as predictors of smoking initiation in a survival analysis model. Results: Shorter BH duration was associated with greater risk of smoking initiation, controlling for nicotine dependence, nicotine withdrawal symptoms, and demographics. Self-report measures of smoking abstinence DI were not associated with BH duration or time to smoking initiation when controlling for nicotine dependence severity. Conclusions: BH captures a domain of DI that is specifically associated with a higher risk of initiating smoking in this analog of smoking lapse. The prediction of smoking in an analog lapse task adds to the extant literature identifying an association between DI and smoking lapse and may enable further research to understand and address the mechanism through which BH affects smoking lapse risk. PMID:23132658

  19. Time-lapse capacitive resistivity imaging: a new technology concept for the monitoring of permafrost

    NASA Astrophysics Data System (ADS)

    Kuras, O.; Krautblatter, M.; Murton, J.; Haslam, E.; Wilkinson, P.; Meldrum, P.

    2011-12-01

    We have investigated and sought to prove a new technology concept for the non-invasive volumetric imaging and routine temporal monitoring of the thermal state of permafrost, a key indicator of global climate change. Capacitive Resistivity Imaging (CRI), a technique based upon low-frequency, capacitively-coupled measurements across permanently installed multi-sensor arrays is applied in order to emulate Electrical Resistivity Tomography (ERT) methodology, but without the need for galvanic contact on frozen soils or rocks. Recent work has shown that temperature-calibrated ERT using galvanic sensors is capable of imaging recession and re-advance of rock permafrost in response to the ambient temperature regime. However, our own laboratory experiments on rock samples under simulated permafrost conditions have equally demonstrated that galvanic electrodes experience large variations in contact resistances between sensors and the host material as the active layer freezes and thaws, leading to a rapid deterioration of data quality over time. As the presence of systematic but uncontrolled sensor noise will reduce the value of time-lapse ERT datasets for monitoring permafrost, the use of galvanic sensors will invariably impose practical limitations on field measurements. The capacitive methodology we are presenting here overcomes this problem and provides a roadmap for making stable resistance measurements with permanently installed sensors over time. We report on our experience with designing, building, testing and validating a functional prototype time-lapse CRI measurement system. The practical system architecture draws upon conceptual ideas incorporated in existing, field-scale CRI instrumentation designed by BGS; however, the use of dense capacitive sensor networks at the laboratory scale and the need for collecting tomographic imaging data across multiple sensors in an automated fashion required a novel technical approach. Our research has applied 4D CRI as well as

  20. Environmental monitoring of leaks using time-lapsed long electrode electrical resistivity

    NASA Astrophysics Data System (ADS)

    Rucker, Dale F.; Fink, James B.; Loke, Meng H.

    2011-08-01

    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. The risk of this occurring 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. Although the method of using long electrodes has been proposed by others, no time-lapse resistivity data have been collected, modeled, and analyzed within a nuclear waste tank farm environment. Therefore, the main objective of this work was to test whether the long electrode method using steel-cased wells can be employed to spatially and temporally track simulated leaks in a highly industrialized setting. A secondary objective was to apply a time-lapse regularization procedure in the inverse modeling code, similar to the 4D tomography approach by Kim et al. (2009), and to test the procedure's effect on the quality of the outcome regarding plume intensity and position. For the synthetic examples, a simple target of varying electrical properties was placed beneath different types of layers of low resistivity to simulate the effects of the infrastructure. Both surface and long electrodes were tested on the synthetic domain, and the test cases covered a variety of survey parameters including low and high electrode density, noise, array type, and the explicit location of the wells relative to the target. All data were processed in four dimensions, where the regularization procedure was applied in both the time and space domains. The synthetic test case showed that the long electrode resistivity method could detect relative changes in resistivity that was commensurate with the differing target properties. The surface electrodes

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

    NASA Astrophysics Data System (ADS)

    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. Geoelectrical time-lapse analysis for improved interpretation of data in a contaminated area

    NASA Astrophysics Data System (ADS)

    Chitea, Florina; Serban, Adrian; Ioane, Dumitru; Georgescu, Paul

    2014-05-01

    Non invasive geoelectrical studies are useful in the preliminary assessment of areas suspected to be contaminated but also in the investigation stage. Correctly adapted to the site specific situation, they are used to detect and investigate buried sources of pollution, to characterize the geology of the area, to detect the contaminated plume or to study the attenuation of pollution in case the appliance of an site-specific remediation techniques. Despite the improved technological acquisition techniques and the optimized inversion data algorithms, interpretation of geoelectrical data in still a challenging task, especially in a contaminated hydrogeological context. Beside the soil physical properties (composition, porosity, texture, etc.), moisture content and chemical composition of the pollutant are also influencing the measured parameter. Apparent electrical resistivity method was use in an area located near an Oil Refinery. Electrical measurements performed on profiles (transverse and along the direction of water flow -according to hydrological data) revealed the presence of contaminants by means of high resistivity anomalies. Using the same acquisition technique (Schlumberger array, same VES points, injection - AB - and voltage - MN - lines extension), measurements were repeated during time, along the same profiles. On the resulted electrical sections from 2006 to 2013, a dynamic situation regarding the pollution plume was observed. Time - lapse analysis, based on the calculation of resistivity differences between sets of data acquired along the same profile was applied, and data interpretation was made using the resulted sections. Significant variation between data sets (> 17% of apparent resistivity normalized differences) observed along the main profile were mainly ranging from the near surface (1.5 m) to an approximated depth (AB/2) of 10m. Using the time-lapse method, changes in the lateral and in depth extension of polluted areas could be observed and

  3. Morphokinetic behavior of euploid and aneuploid embryos analyzed by time-lapse in embryoscope

    PubMed Central

    Patel, Deven V.; Shah, Preeti B.; Kotdawala, Aditi P.; Herrero, Javier; Rubio, Irene; Banker, Manish R.

    2016-01-01

    BACKGROUND: Embryonic aneuploidy may result in miscarriage, implantation failure, or birth defects. Thus, it is clinically necessary to avoid the selection of aneuploid embryos during in vitro fertilization treatment. AIM: The aim of this study was to identify the morphokinetic differences by analyzing the development of euploid and aneuploid embryos using a time-lapse technology. We also checked the accuracy of a previously described model for selection of euploid embryos based on morphokinetics in our study population. MATERIALS AND METHODS: It is a retrospective study of 29 cycles undergoing preimplantation genetic screening from October 2013 to April 2015 at our center. Of 253 embryos, 167 suitable for biopsy embryos were analyzed for their chromosomal status using array-comparative genome hybridization (CGH). The morphokinetic behavior of these embryos was further analyzed in embryoscope using time-lapse technology. RESULTS: Among the analyzed embryos, 41 had normal and 126 had abnormal chromosome content. No significant difference in morphokinetics was found between euploid and aneuploid embryos. The percentage of embryos with blastulation was similar in the euploid (65.85%, 27/41) and aneuploid (60.31%, 76/126) embryos (P = 0.76). Although hard to define, majority of the chromosomal defects might be due to meiotic errors. On applying embryo selection model from Basile et al., embryos falling within optimal ranges for time to division to 5 cells (t5), time period of the third cell cycle (CC3), and time from 2 cell division to 5 cell division (t5-t2) exhibited greater proportion of normal embryos than those falling outside the optimal ranges (28.6%, 25.9%, and 26.7% vs. 17.5%, 20.8%, and 14.3%). CONCLUSION: Keeping a track of time interval between two stages can help us recognize aneuploid embryos at an earlier stage and prevent their selection of transfer. However, it cannot be used as a substitute for array CGH to select euploid embryos for transfer. PMID

  4. Effect of oocyte vitrification on embryo quality: time-lapse analysis and morphokinetic evaluation.

    PubMed

    Cobo, Ana; Coello, Aila; Remohí, Jose; Serrano, Jose; de Los Santos, Jose Maria; Meseguer, Marcos

    2017-09-01

    To analyze whether oocyte vitrification may affect subsequent embryo development from a morphokinetic standpoint by means of time-lapse imaging. Observational cohort study. University-affiliated private IVF center. Ovum donation cycles conducted with the use of vitrified (n = 631 cycles; n = 3,794 embryos) or fresh oocytes (n = 1,359 cycles; n = 9,935 embryos) over 2 years. None. Embryo development was analyzed in a time-lapse imaging incubator. The studied variables included time to 2 cells (t2), 3 cells (t3), 4 cells (t4), 5 cells (t5), morula (tM), and cavitated, early, and hatching blastocyst (tB, tEB, tHB) as well as 2nd cell cycle duration (cc2 = t3 - t2). All of the embryos were classified according to the hierarchic tree model currently used for embryo selection. The analyzed variables were compared with the use of analysis of variance or chi-square and included 95% confidence intervals (CIs). The embryos that originated from vitrified oocytes showed a delay of ∼1 hour from the first division to 2 cells (t2) to the time of blastulation (tB). The embryos that originated from vitrified oocytes showed a delay of ∼1 hour from the 1st division to 2 cells (t2) to the time of blastulation (tB) (P<.05). The proportions of embryos allocated to categories A-E in the hierarchical tree were similar between groups. No differences in implantation rates between the fresh (51.3% [95% CI 47.1%-55.7%]) and vitrified (46.4% [95% CI 38.4%-54.4%]) groups were found. The embryo quality of vitrified oocytes was not impaired: cc2, quality according to our hierarchic morphokinetic model, and implantation rates were similar between fresh and vitrified oocytes. However, morphokinetic differences were observed from t2 to tB. Our main study limitation was the retrospective nature of the analysis, although a large database was studied. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. Fast history matching of time-lapse seismic and production data for high resolution models

    NASA Astrophysics Data System (ADS)

    Jimenez Arismendi, Eduardo Antonio

    Integrated reservoir modeling has become an important part of day-to-day decision analysis in oil and gas management practices. A very attractive and promising technology is the use of time-lapse or 4D seismic as an essential component in subsurface modeling. Today, 4D seismic is enabling oil companies to optimize production and increase recovery through monitoring fluid movements throughout the reservoir. 4D seismic advances are also being driven by an increased need by the petroleum engineering community to become more quantitative and accurate in our ability to monitor reservoir processes. Qualitative interpretations of time-lapse anomalies are being replaced by quantitative inversions of 4D seismic data to produce accurate maps of fluid saturations, pore pressure, temperature, among others. Within all steps involved in this subsurface modeling process, the most demanding one is integrating the geologic model with dynamic field data, including 4Dseismic when available. The validation of the geologic model with observed dynamic data is accomplished through a "history matching" (HM) process typically carried out with well-based measurements. Due to low resolution of production data, the validation process is severely limited in its reservoir areal coverage, compromising the quality of the model and any subsequent predictive exercise. This research will aim to provide a novel history matching approach that can use information from high-resolution seismic data to supplement the areally sparse production data. The proposed approach will utilize streamline-derived sensitivities as means of relating the forward model performance with the prior geologic model. The essential ideas underlying this approach are similar to those used for high-frequency approximations in seismic wave propagation. In both cases, this leads to solutions that are defined along "streamlines" (fluid flow), or "rays" (seismic wave propagation). Synthetic and field data examples will be used

  6. Time-lapse CO2 monitoring using ambient-noise seismic interferometry: a feasibility study from Ketzin, Germany

    NASA Astrophysics Data System (ADS)

    Boullenger, Boris; Verdel, Arie; Paap, Bob; Thorbecke, Jan; Draganov, Deyan

    2015-04-01

    Seismic interferometry applied to ambient-noise measurements allows retrieval of the Green's function between two seismic receivers, by cross-correlating their recordings, as if from a source at one of the receivers. We propose to use ambient-noise seismic interferometry (ANSI) to retrieve reflection data. The time-lapse differences between different vintages of the retrieved data may help characterize property changes within a geologic reservoir with varying CO2 saturation. We test the feasibility of this time-lapse passive seismic method with numerical experiments based on the CO2-storage site of Ketzin, Germany. Ambient-noise recordings from Ketzin exhibit significant passive body-wave energy (from natural tremors or induced seismicity in the vicinity of the reservoir), which is advantageous to retrieve reflections with ANSI. The ANSI numerical experiments aim to understand what the requirements are for the recorded body-wave noise to retrieve the time-lapse reflection signal caused by an increase of CO2 saturation in the reservoir. For this purpose, we design two velocity scenarios at Ketzin: a base scenario before the injection of CO2, and a repeat scenario corresponding to a P-wave velocity decline in the reservoir by 20 percent. For both scenarios, we simulate passive seismic experiments of body-wave noise recordings that may take several days or months to record in the field. The passive recordings are obtained by modelling global (direct wave, internal and surface multiples) transmission responses from band-limited subsurface noise sources, randomly triggered in space and time. The time-lapse reflection signal is obtained by taking the differences between the base and the repeat retrieved reflection data (virtual common-shot gathers). We found that the time-lapse signal is still recovered with ANSI even if the base and repeat retrieved reflection data are partially polluted with artifacts. This means that uneven illumination of the array does not

  7. Subcellular in vivo time-lapse imaging and optical manipulation of Caenorhabditis elegans in standard multiwell plates.

    PubMed

    Rohde, Christopher B; Yanik, Mehmet Fatih

    2011-01-01

    High-resolution in vivo time-lapse assays require repeated immobilization and imaging of whole animals. Here we report a technology for screening Caenorhabditis elegans at cellular resolution over its entire lifespan inside standard multiwell plates using repeated immobilization, imaging and optical manipulation. Our system does not use any fluidic or mechanical components, and can operate for tens of thousands of cycles without failure. It is also compatible with industrial high-throughput screening platforms and robotics, and it allows both chemical, and forward and reverse genetic screens. We used this technology to perform subcellular-resolution femtosecond laser microsurgery of single neurons in vivo, and to image the subsequent regeneration dynamics at subcellular resolution. Our single-neuron in vivo time-lapse analysis shows that neurite regrowth occurring over short time windows is significantly greater than that predicted by ensemble averaging over many animals.

  8. Three dimensional time lapse imaging of live cell mitochondria with photothermal optical lock-in optical coherence microscopy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Sison, Miguel; Chakrabortty, Sabyasachi; Extermann, Jerome; Nahas, Amir; Pache, Christophe; Weil, Tanja; Lasser, Theo

    2016-03-01

    The photothermal optical lock-in optical coherence microscope (poli-OCM) introduced molecular specificity to OCM imaging, which is conventionally, a label-free technique. Here we achieve three-dimensional live cell and mitochondria specific imaging using ~4nm protein-functionalized gold nanoparticles (AuNPs). These nanoparticles do not photobleach and we demonstrate they're suitability for long-term time lapse imaging. We compare the accuracy of labelling with these AuNPs using classical fluorescence confocal imaging with a standard mitochondria specific marker. Furthermore, time lapse poli-OCM imaging every 5 minutes over 1.5 hours period was achieved, revealing the ability for three-dimensional monitoring of mitochondria dynamics.

  9. TLM-Tracker: software for cell segmentation, tracking and lineage analysis in time-lapse microscopy movies.

    PubMed

    Klein, Johannes; Leupold, Stefan; Biegler, Ilona; Biedendieck, Rebekka; Münch, Richard; Jahn, Dieter

    2012-09-01

    Time-lapse imaging in combination with fluorescence microscopy techniques enable the investigation of gene regulatory circuits and uncovered phenomena like culture heterogeneity. In this context, computational image processing for the analysis of single cell behaviour plays an increasing role in systems biology and mathematical modelling approaches. Consequently, we developed a software package with graphical user interface for the analysis of single bacterial cell behaviour. A new software called TLM-Tracker allows for the flexible and user-friendly interpretation for the segmentation, tracking and lineage analysis of microbial cells in time-lapse movies. The software package, including manual, tutorial video and examples, is available as Matlab code or executable binaries at http://www.tlmtracker.tu-bs.de.

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

    NASA Astrophysics Data System (ADS)

    Pedersen, Jonas N.; Li, Liang; Grǎdinaru, Cristian; Austin, Robert H.; Cox, Edward C.; Flyvbjerg, Henrik

    2016-12-01

    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 sampling frequency of time-lapse recording, by experimental errors on recorded positions, and by conditional averaging. We give exact analytical expressions for these effects in the simplest possible model for persistent random motion, the Ornstein-Uhlenbeck process. Then we describe those aspects of these effects that are valid for any reasonable model for persistent random motion. Our findings are illustrated with experimental data and Monte Carlo simulations.

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

    PubMed

    Nørrelykke, Simon F; Flyvbjerg, Henrik

    2011-04-01

    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-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 to the extent that it is interpreted as a damped harmonic oscillator at finite temperature-such as an AFM cantilever. (iii) Three other models of fundamental interest are limiting cases of the damped harmonic oscillator at finite temperature; it consequently bridges their differences and describes the effects of finite sampling rate and sampling time for these models as well. ©2011 American Physical Society

  12. Non-rigid estimation of cell motion in calcium time-lapse images

    NASA Astrophysics Data System (ADS)

    Hachi, Siham; Lucumi Moreno, Edinson; Desmet, An-Sofie; Vanden Berghe, Pieter; Fleming, Ronan M. T.

    2016-03-01

    Calcium imaging is a widely used technique in neuroscience permitting the simultaneous monitoring of electro- physiological activity of hundreds of neurons at single cell resolution. Identification of neuronal activity requires rapid and reliable image analysis techniques, especially when neurons fire and move simultaneously over time. Traditionally, image segmentation is performed to extract individual neurons in the first frame of a calcium sequence. Thereafter, the mean intensity is calculated from the same region of interest in each frame to infer calcium signals. However, when cells move, deform and fire, this segmentation on its own generates artefacts and therefore biased neuronal activity. Therefore, there is a pressing need to develop a more efficient cell tracking technique. We hereby present a novel vision-based cell tracking scheme using a thin-plate spline deformable model. The thin-plate spline warping is based on control points detected using the Fast from Accelerated Segment Test descriptor and tracked using the Lucas-Kanade optical flow. Our method is able to track neurons in calcium time-series, even when there are large changes in intensity, such as during a firing event. The robustness and efficiency of the proposed approach is validated on real calcium time-lapse images of a neuronal population.

  13. Endoscopic Time-Lapse Imaging of Immune Cells in Infarcted Mouse Hearts

    PubMed Central

    Leuschner, Florian; Gorbatov, Rostic; Kim, Jun Ki; Ueno, Takuya; Nahrendorf, Matthias; Yun, Seok Hyun

    2013-01-01

    Rationale High-resolution imaging of the heart in vivo is challenging due to the difficulty in accessing the heart and the tissue motion caused by the heartbeat. Objective Here, we describe a suction-assisted endoscope for visualizing fluorescently labeled cells and vessels in the beating heart tissue through a small incision made in the intercostal space. Methods and Results A suction tube with a diameter of 2-3 mm stabilizes the local tissue motion safely and effectively at a suction pressure of 50 mmHg. Using a minimally invasive endoscope integrated into a confocal microscope, we performed fluorescence cellular imaging in both normal and diseased hearts in live mice for an hour per session repeatedly over a few weeks. Real-time imaging revealed the surprisingly rapid infiltration of CX3CR1+ monocytes into the injured site within several minutes after acute myocardial infarction (MI). Conclusions The time-lapse analysis of flowing and rolling (patrolling) monocytes in the heart and the peripheral circulation provide evidence that the massively recruited monocytes come first from the vascular reservoir and later from the spleen. The imaging method requires minimal surgical preparation and can be implemented into standard intravital microscopes. Our results demonstrate the applicability of our imaging method for a wide range of cardiovascular research. PMID:23392842

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

    USGS Publications Warehouse

    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.

  15. Value of Information Analysis for Time-lapse Seismic Data by Simulation-Regression

    NASA Astrophysics Data System (ADS)

    Dutta, G.; Mukerji, T.; Eidsvik, J.

    2016-12-01

    A novel method to estimate the Value of Information (VOI) of time-lapse seismic data in the context of reservoir development is proposed. VOI is a decision analytic metric quantifying the incremental value that would be created by collecting information prior to making a decision under uncertainty. The VOI has to be computed before collecting the information and can be used to justify its collection. Previous work on estimating the VOI of geophysical data has involved explicit approximation of the posterior distribution of reservoir properties given the data and then evaluating the prospect values for that posterior distribution of reservoir properties. Here, we propose to directly estimate the prospect values given the data by building a statistical relationship between them using regression. Various regression techniques such as Partial Least Squares Regression (PLSR), Multivariate Adaptive Regression Splines (MARS) and k-Nearest Neighbors (k-NN) are used to estimate the VOI, and the results compared. For a univariate Gaussian case, the VOI obtained from simulation-regression has been shown to be close to the analytical solution. Estimating VOI by simulation-regression is much less computationally expensive since the posterior distribution of reservoir properties given each possible dataset need not be modeled and the prospect values need not be evaluated for each such posterior distribution of reservoir properties. This method is flexible, since it does not require rigid model specification of posterior but rather fits conditional expectations non-parametrically from samples of values and data.

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

    PubMed Central

    Redi, Carlo Alberto; Zuccotti, Maurizio

    2014-01-01

    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. PMID:24864231

  17. Metamorphosis revealed: time-lapse three-dimensional imaging inside a living chrysalis

    PubMed Central

    Lowe, Tristan; Garwood, Russell J.; Simonsen, Thomas J.; Bradley, Robert S.; Withers, Philip J.

    2013-01-01

    Studies of model insects have greatly increased our understanding of animal development. Yet, they are limited in scope to this small pool of model species: a small number of representatives for a hyperdiverse group with highly varied developmental processes. One factor behind this narrow scope is the challenging nature of traditional methods of study, such as histology and dissection, which can preclude quantitative analysis and do not allow the development of a single individual to be followed. Here, we use high-resolution X-ray computed tomography (CT) to overcome these issues, and three-dimensionally image numerous lepidopteran pupae throughout their development. The resulting models are presented in the electronic supplementary material, as are figures and videos, documenting a single individual throughout development. They provide new insight and details of lepidopteran metamorphosis, and allow the measurement of tracheal and gut volume. Furthermore, this study demonstrates early and rapid development of the tracheae, which become visible in scans just 12 h after pupation. This suggests that there is less remodelling of the tracheal system than previously expected, and is methodologically important because the tracheal system is an often-understudied character system in development. In the future, this form of time-lapse CT-scanning could allow faster and more detailed developmental studies on a wider range of taxa than is presently possible. PMID:23676900

  18. Deciphering the Receptor Repertoire Encoding Specific Odorants by Time-Lapse Single-Cell Array Cytometry

    PubMed Central

    Suzuki, Masato; Yoshimoto, Nobuo; Shimono, Ken; Kuroda, Shun’ichi

    2016-01-01

    Mammals can recognize a vast number of odorants by using olfactory receptors (ORs) known as G protein-coupled receptors. The OR gene family is one of the most diverse gene families in mammalian genomes. Because of the vast combinations of ORs and odorants, few ORs have thus far been linked to specific odorants. Here, we established a functional screening method for OR genes by using a microchamber array containing >5,400 single olfactory epithelium-derived cells from mice applied to time-lapse single-cell array cytometry. This method facilitated the prompt isolation of single olfactory sensory neurons (OSNs) responding to the odorant of interest. Subsequent single-cell RT-PCR allowed us to isolate the genes encoding respective ORs. By using volatile molecules recognized as biomarkers for lung cancers, this method could deorphanize ORs and thereby reconstitute the OR-mediated signaling cascade in HEK293T cells. Thus, our system could be applied to identify any receptor by using specific ligands in the fields of physiopathology and pharmacology. PMID:26832639

  19. Protein kinase A catalytic subunit primed for action: Time-lapse crystallography of Michaelis complex formation

    DOE PAGES

    Das, Amit; Gerlits, Oksana O.; Parks, Jerry M.; ...

    2015-11-12

    The catalytic subunit of the cyclic AMP-dependent protein kinase A (PKAc) catalyzes the transfer of the γ-phosphate of bound Mg2ATP to a serine or threonine residue of a protein substrate. Here, time-lapse X-ray crystallography was used to capture a series of complexes of PKAc with an oligopeptide substrate and unreacted Mg2ATP, including the Michaelis complex, that reveal important geometric rearrangements in and near the active site preceding the phosphoryl transfer reaction. Contrary to the prevailing view, Mg2+ binds first to the M1 site as a complex with ATP and is followed by Mg2+ binding to the M2 site. Furthermore, themore » target serine hydroxyl of the peptide substrate rotates away from the active site toward the bulk solvent, which breaks the hydrogen bond with D166. In conclusion, the serine hydroxyl of the substrate rotates back toward D166 to form the Michaelis complex with the active site primed for phosphoryl transfer.« less

  20. Time-lapse lab-based x-ray nano-CT study of corrosion damage.

    PubMed

    Bradley, R S; Liu, Y; Burnett, T L; Zhou, X; Lyon, S B; Withers, P J; Gholinia, A; Hashimoto, T; Graham, D; Gibbon, S R; Hornberger, B

    2017-07-01

    An experimental protocol (workflow) has been developed for time-lapse x-ray nanotomography (nano-CT) imaging of environmentally driven morphological changes to materials. Two case studies are presented. First, the leaching of nanoparticle corrosion inhibitor pigment from a polymer coating was followed over 14 days, while in the second case the corrosion damage to an AA2099 aluminium alloy was imaged over 12 hours. The protocol includes several novel aspects relevant to nano-CT with the use of a combination of x-ray absorption and phase contrast data to provide enhanced morphological and composition information, and hence reveal the best information to provide new insights into the changes of different phases over time. For the pigmented polymer coating containing nominally strontium aluminium polyphosphate, the strontium-rich components within the materials are observed to leach extensively whereas the aluminium-rich components are more resistant to dissolution. In the case of AA2099 it is found that the initial grain boundary corrosion is driven by the presence of copper-rich phases and is then followed by the corrosion of grains of specific orientation. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  1. Time lapse 3D geoelectric measurements for monitoring of in-situ remediation

    NASA Astrophysics Data System (ADS)

    Tildy, Péter; Neducza, Boriszláv; Nagy, Péter; Kanli, Ali Ismet; Hegymegi, Csaba

    2017-01-01

    In the last decade, different kinds of in-situ methods have been increasingly used for hydrocarbon contamination remediation due to their effectiveness. One of these techniques operates by injection of chemical oxidant solution to remove (degrade) the subsurface contaminants. Our aim was to develop a surface (non-destructive) measurement strategy to monitor oxidative in-situ remediation processes. The difficulties of the presented study originate from the small volume of conductive solution that can be used due to environmental considerations, the effect of conductive groundwater and the high clay content of the targeted layer. Therefore a site specific synthetic modelling was necessary for measurement design involving the results of preliminary 2D ERT measurements, electrical conductivity measurements of different active agents and expected resistivity changes calculated by soil resistivity modelling. The results of soil resistivity modelling have suggested that the reagent have complex effects on contaminated soils because of chemical biodegradation. As a result the plume of resistivity changes caused by the injected agent was determined showing strong fracturing effect because of the high pressure of injection. Based on the sophisticated tests and synthetic modelling 3D time-lapse geo-electric measurements were proven to provide a usable monitoring tool for in-situ remediation to help in-field design of such techniques.

  2. Landslide monitoring in southwestern China via time-lapse electrical resistivity tomography

    NASA Astrophysics Data System (ADS)

    Xu, Dong; Hu, Xiang-Yun; Shan, Chun-Ling; Li, Rui-Heng

    2016-03-01

    The dynamic monitoring of landslides in engineering geology has focused on the correlation among landslide stability, rainwater infiltration, and subsurface hydrogeology. However, the understanding of this complicated correlation is still poor and inadequate. Thus, in this study, we investigated a typical landslide in southwestern China via time-lapse electrical resistivity tomography (TLERT) in November 2013 and August 2014. We studied landslide mechanisms based on the spatiotemporal characteristics of surface water infiltration and flow within the landslide body. Combined with borehole data, inverted resistivity models accurately defined the interface between Quaternary sediments and bedrock. Preferential flow pathways attributed to fracture zones and fissures were also delineated. In addition, we found that surface water permeates through these pathways into the slipping mass and drains away as fissure water in the fractured bedrock, probably causing the weakly weathered layer to gradually soften and erode, eventually leading to a landslide. Clearly, TLERT dynamic monitoring can provide precursory information of critical sliding and can be used in landslide stability analysis and prediction.

  3. Attentional Lapses of Adults with Attention Deficit Hyperactivity Disorder in Tasks of Sustained Attention.

    PubMed

    Gmehlin, Dennis; Fuermaier, Anselm B M; Walther, Stephan; Tucha, Lara; Koerts, Janneke; Lange, Klaus W; Tucha, Oliver; Weisbrod, Matthias; Aschenbrenner, Steffen

    2016-06-01

    Adults with attention deficit hyperactivity disorder (ADHD) show attentional dysfunction such as distractibility and mind-wandering, especially in lengthy tasks. However, fundamentals of dysfunction are ambiguous and relationships of neuropsychological test parameters with self-report measures of ADHD symptoms are marginal. We hypothesize that basic deficits in sustaining attention explain more complex attentional dysfunction in persons with ADHD and relate to ADHD symptoms. Attentional function was analyzed by computing ex-Gaussian parameters for 3 time Blocks in a 20 min test of sustained alertness. Changes in performance across these blocks were analyzed by comparing adult persons with ADHD (n = 24) with healthy matched controls (n = 24) and correlated with neuropsychological measures of selective and divided attention as well as self-report measures of ADHD symptoms. We found a significantly steeper increase in the number of slow responses (ex-Gaussian parameter τ) in persons with ADHD with time on task in basic sustained alertness. They also performed significantly worse in tasks of sustained selective and divided attention. However, after controlling for an increase in τ during the alertness task, significant differences between groups disappeared for divided and partly selective attention. Increases in τ in the sustained alertness task correlated significantly with self-report measures of ADHD symptoms. Our results provide evidence that very basic deficits in sustaining attention in adults with ADHD are related to infrequent slow responses (=attentional lapses), with changes over time being relevant for more complex attentional function and experienced ADHD symptoms in everyday life.

  4. Time-lapse characterization of hydrothermal seawater and microbial interactions with basaltic tephra at Surtsey Volcano

    NASA Astrophysics Data System (ADS)

    Jackson, M. D.; Gudmundsson, M. T.; Bach, W.; Cappelletti, P.; Coleman, N. J.; Ivarsson, M.; Jónasson, K.; Jørgensen, S. L.; Marteinsson, V.; McPhie, J.; Moore, J. G.; Nielson, D.; Rhodes, J. M.; Rispoli, C.; Schiffman, P.; Stefánsson, A.; Türke, A.; Vanorio, T.; Weisenberger, T. B.; White, J. D. L.; Zierenberg, R.; Zimanowski, B.

    2015-12-01

    A new International Continental Drilling Program (ICDP) project will drill through the 50-year-old edifice of Surtsey Volcano, the youngest of the Vestmannaeyjar Islands along the south coast of Iceland, to perform interdisciplinary time-lapse investigations of hydrothermal and microbial interactions with basaltic tephra. The volcano, created in 1963-1967 by submarine and subaerial basaltic eruptions, was first drilled in 1979. In October 2014, a workshop funded by the ICDP convened 24 scientists from 10 countries for 3 and a half days on Heimaey Island to develop scientific objectives, site the drill holes, and organize logistical support. Representatives of the Surtsey Research Society and Environment Agency of Iceland also participated. Scientific themes focus on further determinations of the structure and eruptive processes of the type locality of Surtseyan volcanism, descriptions of changes in fluid geochemistry and microbial colonization of the subterrestrial deposits since drilling 35 years ago, and monitoring the evolution of hydrothermal and biological processes within the tephra deposits far into the future through the installation of a Surtsey subsurface observatory. The tephra deposits provide a geologic analog for developing specialty concretes with pyroclastic rock and evaluating their long-term performance under diverse hydrothermal conditions. Abstracts of research projects are posted at http://surtsey.icdp-online.org.

  5. Imaging Rainfall Infiltration Processes with the Time-Lapse Electrical Resistivity Imaging Method

    NASA Astrophysics Data System (ADS)

    Zhang, Gang; Zhang, Gui-Bin; Chen, Chien-chih; Chang, Ping-Yu; Wang, Tzu-Pin; Yen, Horng-Yuan; Dong, Jia-Jyun; Ni, Chuen-Fa; Chen, Su-Chin; Chen, Chao-Wei; Jia, Zheng-yuan

    2016-06-01

    Electrical Resistivity Imaging (ERI) was carried out continuously for 10 days to map the subsurface resistivity distribution along a potentially hazardous hillslope at the Jieshou Junior High School in Taoyuan, Taiwan. The reliability of the inverted resistivity structures down to about 25 m depth was examined with synthetic modeling using the same electrode arrangements installed on land surface as in field surveys, together with a DOI (depth-of-investigation) index calculated from the ERI data. The subsurface resistivity distribution is consistent with results from well logging. These ERI recordings were taken daily and provided highly resolved imagery of the resistivity distribution underground and illustrated the dynamical fluid-flow behavior due to heavy rainfall infiltration. Using Archie's law, the resistivity distribution was transformed into a map of relative water saturation (RWS), which is strongly correlated with the rainfall infiltration process. We then found that the averaged RWS is significantly correlated with daily precipitation. Our observations indicate that time-lapse ERI is effective in monitoring subterraneous rainfall infiltration; moreover, the preferential flow paths can be delineated according to the changes in averaged RWS derived from the ERI data.

  6. Setting up a groundwater recharge model for an arid karst system using time lapse camera data

    NASA Astrophysics Data System (ADS)

    Schulz, Stephan; de Rooij, Gerrit H.; Michelsen, Nils; Rausch, Randolf; Siebert, Christian; Schüth, Christoph; Merz, Ralf

    2015-04-01

    Groundwater is the principal water resource in most dryland areas. Therefore, its replenishment rate is of great importance for water management. The amount of groundwater recharge depends on the climatic conditions, but also on the geological conditions, soil properties and vegetation. In dryland areas, outcrops of karst aquifers often receive enhanced recharge rates compared to other geological settings. Especially in areas with exposed karst features like sinkholes or open shafts rainfall accumulates in channels and discharges directly into the aquifer. Using the example of the As Sulb plateau in Saudi Arabia this study introduces a cost-effective and robust method for recharge monitoring and modelling in karst outcrops. The measurement of discharge of a small catchment (4.0 x 104 m2) into a sinkhole, and hence the direct recharge into the aquifer, was carried out with a time lapse camera observing a v-notch weir. During the monitoring period of two rainy seasons (autumn 2012 to spring 2014) four recharge events were recorded. Afterwards, recharge data as well as proxy data about the drying of the sediment cover are used to set up a conceptual water balance model. This model was run for 17 years (1971 to 1986 and 2012 to 2014). Simulation results show highly variable seasonal recharge-precipitation-ratios, which underlines the nonlinearity between recharge and precipitation in dryland areas. Besides the amount of precipitation this ratio is strongly influenced by the interannual distribution of rainfall events.

  7. Distortion effects in a switch array UWB radar for time-lapse imaging of human heartbeats

    NASA Astrophysics Data System (ADS)

    Brovoll, Sverre; Berger, Tor; Aardal, Åyvind; Lande, Tor S.; Hamran, Svein-Erik

    2014-05-01

    Cardiovascular diseases (CVD) are a major cause of deaths all over the world. Microwave radar can be an alternative sensor for heart diagnostics and monitoring in modern healthcare that aids early detection of CVD symptoms. In this paper measurements from a switch array radar system are presented. This UWB system operates below 3 GHz and does time-lapse imaging of the beating heart inside the human body. The array consists of eight fat dipole elements. With a switch system, every possible sequence of transmit/receive element pairs can be selected to build a radar image from the recordings. To make the radar waves penetrate the human tissue, the antenna array is placed in contact with the body. Removal of the direct signal leakage through the antennas and body surface are done by high-pass (HP) filtering of the data prior to image processing. To analyze the results, measurements of moving spheres in air and simulations are carried out. We see that removal of the direct signal introduces amplitude distortion in the images. In addition, the effect of small target motion between the collection times of data from the individual elements is analyzed. With low pulse repetition frequency (PRF) this motion will distort the image. By using data from real measurements of heart motion in simulations, we analyze how the PRF and the antenna geometry influence this distortions.

  8. Lapses in skin conductance responding across anatomical sites: Comparison of fingers, feet, forehead, and wrist.

    PubMed

    Payne, Andrew F H; Schell, Anne M; Dawson, Michael E

    2016-07-01

    The fingers are widely accepted as the gold standard for skin conductance (SC) recording, with the feet as a strong alternative. However, there are gaps in the current literature comparing these sites. There is also a great deal of interest in alternative recording sites to permit mobility, but data evaluating these are few and inconsistent. The present report compared multiple sites (fingers, abductor hallucis of the foot, arch of the foot, toes, forehead, and wrist) from 45 college student participants in a short-term sedentary laboratory setting and found large variation in both tonic and phasic SC responses, as well as crucial lapses in responding at nonpalmar sites. Across-site correlations between participants and within participants were also examined. The present data show that, in the laboratory setting employing commonly used recording techniques and stimuli, the nonpalmar sites are generally less responsive than the fingers, and the wrist in particular is the lowest in responding, whereas the toes are most similar to the fingers in responding. Within-participant correlations between the fingers and other sites were greatest for the plantar sites and least for the forehead. © 2016 Society for Psychophysiological Research.

  9. Estimating the onset of time-lapse changes: A robust basis for reservoir monitoring and characterization

    NASA Astrophysics Data System (ADS)

    Vasco, D. W.

    2013-12-01

    Time-lapse monitoring is useful for imaging flow related changes in geophysical attributes. However, it can be difficult to relate changes in geophysical observations to changes in saturation and pressure in a reservoir. As an alternative approach for reservoir monitoring and characterization, we introduce the idea of an onset time, the time at which measured quantities, such as seismic travel times or reflection amplitudes, begin to deviate from their background values. We illustrate the idea of an onset time and demonstrate its utility through the consideration of travel times recorded by the Continuous Active Source Seismic Monitoring (CASSM) system at the Frio pilot site near Houston, Texas. The system, which transmits an elastic wave every 15 minutes, is used to monitor the movement of carbon dioxide injected into a permeable sand formation. From these data we can estimate the onset of changes in seismic travel times to six receivers in an adjacent borehole. Numerical simulation and synthetic tests indicate that the onset times are not very sensitive to the method used to compute the effective fluid bulk modulus and, correspondingly, the seismic compressional velocity. Rather, the onset times are strongly influenced by saturation changes within the formation, specifically by the break-through time of the injected fluid phase. By means of an iterative inversion algorithm we use the onset times to estimate permeability variations between the boreholes at the Frio pilot site.

  10. Designing genetic algorithm for efficient calculation of value encoding in time-lapse gravity inversion

    NASA Astrophysics Data System (ADS)

    Wahyudi, Eko Januari

    2013-09-01

    As advancing application of soft computation technique in oil and gas industry, Genetic Algorithm (GA) also shows contribution in geophysical inverse problems in order to achieve better results and efficiency in computational process. In this paper, I would like to show the progress of my work in inverse modeling of time-lapse gravity data uses value encoding with alphabet formulation. The alphabet formulation designed to provide solution of characterization positive density change (+Δρ) and negative density change (-Δρ) respect to reference value (0 gr/cc). The inversion that utilize discrete model parameter, computed with GA as optimization algorithm. The challenge working with GA is take long time computational process, so the step in designing GA in this paper described through evaluation on GA operators performance test. The performances of several combinations of GA operators (selection, crossover, mutation, and replacement) tested with synthetic model in single-layer reservoir. Analysis on sufficient number of samples shows combination of SUS-MPCO-QSA/G-ND as the most promising results. Quantitative solution with more confidence level to characterize sharp boundary of density change zones was conducted with average calculation of sufficient model samples.

  11. 4D inversion of time-lapse magnetotelluric data sets for monitoring geothermal reservoir

    NASA Astrophysics Data System (ADS)

    Nam, Myung Jin; Song, Yoonho; Jang, Hannuree; Kim, Bitnarae

    2017-06-01

    The productivity of a geothermal reservoir, which is a function of the pore-space and fluid-flow path of the reservoir, varies since the properties of the reservoir changes with geothermal reservoir production. Because the variation in the reservoir properties causes changes in electrical resistivity, time-lapse (TL) three-dimensional (3D) magnetotelluric (MT) methods can be applied to monitor the productivity variation of a geothermal reservoir thanks to not only its sensitivity to the electrical resistivity but also its deep depth of survey penetration. For an accurate interpretation of TL MT-data sets, a four-dimensional (4D) MT inversion algorithm has been developed to simultaneously invert all vintage data considering time-coupling between vintages. However, the changes in electrical resistivity of deep geothermal reservoirs are usually small generating minimum variation in TL MT responses. Maximizing the sensitivity of inversion to the changes in resistivity is critical in the success of 4D MT inversion. Thus, we further developed a focused 4D MT inversion method by considering not only the location of a reservoir but also the distribution of newly-generated fractures during the production. For the evaluation of the 4D MT algorithm, we tested our 4D inversion algorithms using synthetic TL MT-data sets.

  12. Direct prediction of spatially and temporally varying physical properties from time-lapse electrical resistance data

    NASA Astrophysics Data System (ADS)

    Hermans, Thomas; Oware, Erasmus; Caers, Jef

    2016-09-01

    Time-lapse applications of electrical methods have grown significantly over the last decade. However, the quantitative interpretation of tomograms in terms of physical properties, such as salinity, temperature or saturation, remains difficult. In many applications, geophysical models are transformed into hydrological models, but this transformation suffers from spatially and temporally varying resolution resulting from the regularization used by the deterministic inversion. In this study, we investigate a prediction-focused approach (PFA) to directly estimate subsurface physical properties with electrical resistance data, circumventing the need for classic tomographic inversions. First, we generate a prior set of resistance data and physical property forecast through hydrogeological and geophysical simulations mimicking the field experiment. We reduce the dimension of both the data and the forecast through principal component analysis in order to keep the most informative part of both sets in a reduced dimension space. Then, we apply canonical correlation analysis to explore the relationship between the data and the forecast in their reduced dimension space. If a linear relationship can be established, the posterior distribution of the forecast can be directly sampled using a Gaussian process regression where the field data scores are the conditioning data. In this paper, we demonstrate PFA for various physical property distributions. We also develop a framework to propagate the estimated noise level in the reduced dimension space. We validate the results by a Monte Carlo study on the posterior distribution and demonstrate that PFA yields accurate uncertainty for the cases studied.

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

    NASA Technical Reports Server (NTRS)

    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.

  14. Time-lapse crosswell seismic and VSP monitoring of injected CO2 ina brine aquifer

    SciTech Connect

    Daley, Thomas M.; Myer, Larry R.; Peterson, J.E.; Majer, E.L.; Hoversten,G.M.

    2006-05-30

    Seismic surveys successfully imaged a small scale C02injection (1,600 tons) conducted in a brine aquifer of the Frio Formationnear Houston, Texas. These time-lapse bore-hole seismic surveys,crosswell and vertical seismic profile (VSP), were acquired to monitorthe C02 distribution using two boreholes (the new injection well and apre-existing well used for monitoring) which are 30 m apart at a depth of1500 m. The crosswell survey provided a high-resolution image of the C02distribution between the wells via tomographic imaging of the P-wavevelocity decrease (up to 500 mls). The simultaneously acquired S-wavetomography showed little change in S-wave velocity, as expected for fluidsubstitution. A rock physics model was used to estimate C02 saturationsof 10-20 percent from the P-wave velocity change. The VSP survey resolveda large (-70 percent) change in reflection amplitude for the Friohorizon. This C02 induced reflection amplitude change allowed estimationof the C02 extent beyond the monitor well and on 3 azimuths. The VSPresult is compared with numerical modeling of C02 saturations and isseismically modeled using the velocity change estimated in the crosswellsurvey.

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Landslide Monitoring in Southwestern China via Time-lapse Electrical Resistivity Tomography

    NASA Astrophysics Data System (ADS)

    Xu, D.; Hu, X.; Shan, C.

    2016-12-01

    The dynamic monitoring of landslides in engineering geology has focused on the correlation among landslide stability, rainwater infiltration, and subsurface hydrogeology. However, the understanding of this complicated correlation is still poor and inadequate. Thus, in this study, we investigated a typical landslide in southwestern China via time-lapse electrical resistivity tomography (TLERT) in November 2013, August 2014 and May 2016. From the data, shallow sediments showed short-term resistivity variability due to evaporation and rainfall, whereas deep zone exhibited seasonal fluctuations related to dry season, rainy season and snow melting during springtime. We also studied landslide mechanisms based on the spatiotemporal characteristics of surface water infiltration and flow within the landslide body. Combined with borehole data, inverted resistivity models accurately defined the interface between Quaternary sediments and bedrock. Preferential flow pathways attributed to fracture zones and fissures were also delineated. In addition, we found that surface water permeates through these pathways into the slipping mass and drains away as fissure water in the fractured bedrock, probably causing the weakly weathered layer to gradually soften and erode, eventually leading to a landslide. Clearly, TLERT dynamic monitoring can provide precursory information of critical sliding and can be used in landslide stability analysis and prediction.

  17. Determination of water saturation using gas phase partitioning tracers and time-lapse electrical conductivity measurements

    SciTech Connect

    Johnson, Timothy C.; Oostrom, Martinus; Truex, Michael J.; Thomle, Jonathan N.; Wietsma, Thomas W.

    2013-05-21

    Water saturation is an important indicator of contaminant distribution and plays a governing role in contaminant transport within the vadose zone. Understanding the water saturation distribution is critical for both remediation and contaminant flux monitoring in unsaturated environments. In this work we propose and demonstrate a method of remotely determining water saturation levels using gas phase partitioning tracers and time-lapse bulk electrical conductivity measurements. The theoretical development includes the partitioning chemistry for the tracers we demonstrate (ammonia and carbon dioxide), as well as a review of the petrophysical relationship governing how these tracers influence bulk conductivity. We also investigate methods of utilizing secondary information provided by electrical conductivity breakthrough magnitudes induced by the tracers. We test the method on clean, well characterized, intermediate-scale sand columns under controlled conditions. Results demonstrate the capability to predict partitioning coefficients and accurately monitor gas breakthrough curves along the length of the column according to the corresponding electrical conductivity response, leading to accurate water saturation estimates. This work is motivated by the need to develop effective characterization and monitoring techniques for contaminated deep vadose zone environments, and provides a proof-of-concept toward uniquely characterizing and monitoring water saturation levels at the field scale and in three-dimensions using electrical resistivity tomography.

  18. Mathematical analysis of endothelial sibling pair cell-cell interactions using time-lapse cinematography data.

    PubMed

    Brown, L M; Ryan, U S; Absher, M; Olazabal, B M

    1982-01-01

    The sibling pairs from two different endothelial cell cultures were analysed by time-lapse cinematography. It was shown that wounded and regular (low density seeded) cultures differed in the behaviour patterns of their siblings. The cultures differed most significantly in the minimum interdivision time (IDT) which was 27% lower for the wounded culture. In the wounded culture there was a greater correlation of IDT values between sibling pairs. IDT values recorded both for paired and for unpaired cells were shorter for the wounded than for the regular culture. The mean IDT for unpaired cells was longer than the mean IDT for paired cells in the regular culture. Thus paired cells in the regular culture, had shorter IDTs, but not as short as in the wounded culture. It was significant that in the wounded culture the first generation of siblings were very close (less than 150 microns apart) at division. Overall the behaviour differences between the two cultures resulted in a higher rate of increase in cell numbers, and thus faster repair, of the wounded monolayer.

  19. Segmentation Method of Time-Lapse Microscopy Images with the Focus on Biocompatibility Assessment.

    PubMed

    Soukup, Jindřich; Císař, Petr; Šroubek, Filip

    2016-06-01

    Biocompatibility testing of new materials is often performed in vitro by measuring the growth rate of mammalian cancer cells in time-lapse images acquired by phase contrast microscopes. The growth rate is measured by tracking cell coverage, which requires an accurate automatic segmentation method. However, cancer cells have irregular shapes that change over time, the mottled background pattern is partially visible through the cells and the images contain artifacts such as halos. We developed a novel algorithm for cell segmentation that copes with the mentioned challenges. It is based on temporal differences of consecutive images and a combination of thresholding, blurring, and morphological operations. We tested the algorithm on images of four cell types acquired by two different microscopes, evaluated the precision of segmentation against manual segmentation performed by a human operator, and finally provided comparison with other freely available methods. We propose a new, fully automated method for measuring the cell growth rate based on fitting a coverage curve with the Verhulst population model. The algorithm is fast and shows accuracy comparable with manual segmentation. Most notably it can correctly separate live from dead cells.

  20. Early events in insulin fibrillization studied by time-lapse atomic force microscopy.

    PubMed

    Podestà, Alessandro; Tiana, Guido; Milani, Paolo; Manno, Mauro

    2006-01-15

    The importance of understanding the mechanism of protein aggregation into insoluble amyloid fibrils lies not only in its medical consequences, but also in its more basic properties of self-organization. The discovery that a large number of uncorrelated proteins can form, under proper conditions, structurally similar fibrils has suggested that the underlying mechanism is a general feature of polypeptide chains. In this work, we address the early events preceding amyloid fibril formation in solutions of zinc-free human insulin incubated at low pH and high temperature. Here, we show by time-lapse atomic force microscopy that a steady-state distribution of protein oligomers with a quasiexponential tail is reached within a few minutes after heating. This metastable phase lasts for a few hours, until fibrillar aggregates are observable. Although for such complex systems different aggregation mechanisms can occur simultaneously, our results indicate that the prefibrillar phase is mainly controlled by a simple coagulation-evaporation kinetic mechanism, in which concentration acts as a critical parameter. These experimental facts, along with the kinetic model used, suggest a critical role for thermal concentration fluctuations in the process of fibril nucleation.

  1. Time-lapse imaging of human heart motion with switched array UWB radar.

    PubMed

    Brovoll, Sverre; Berger, Tor; Paichard, Yoann; Aardal, Øyvind; Lande, Tor Sverre; Hamran, Svein-Erik

    2014-10-01

    Radar systems for detection of human heartbeats have mostly been single-channel systems with limited spatial resolution. In this paper, a radar system for ultra-wideband (UWB) imaging of the human heart is presented. To make the radar waves penetrate the human tissue the antenna is placed very close to the body. The antenna is an array with eight elements, and an antenna switch system connects the radar to the individual elements in sequence to form an image. Successive images are used to build up time-lapse movies of the beating heart. Measurements on a human test subject are presented and the heart motion is estimated at different locations inside the body. The movies show rhythmic motion consistent with the beating heart, and the location and shape of the reflections correspond well with the expected response form the heart wall. The spatial dependent heart motion is compared to ECG recordings, and it is confirmed that heartbeat modulations are seen in the radar data. This work shows that radar imaging of the human heart may provide valuable information on the mechanical movement of the heart.

  2. The impact of male age on embryo quality: a retrospective study using time-lapse imaging

    PubMed Central

    Rosário, Guilherme R. F.; Vidal, Diana S.; Silva, Adriana V.; Franco, Antônio C. C.

    2016-01-01

    Objective This study aimed to correlate male age with embryo morphokinetic parameters on D3 considering the timing and the exact moment of embryo cleavage. Methods Time-lapse imaging was used to produce an ideal cleavage curve for the embryos analyzed. The percentage of embryos under the curve was analyzed and correlated with male age. Results 32.6% of the embryos from patients aged 28-33 years were under the curve; 36.2% of the embryos from patients aged 34-39 years were under the curve; 41.3% of the embryos from patients aged 40-45 years were under the curve; and 26.3% of the embryos fro patients aged 46-57 years were under the curve. Conclusions a statistically non-significant decrease was observed in the percentage of embryos under the optimal cleavage curve on D3 in the group of men aged between 40 and 45 years. Further studies looking into embryos in the blastocyst stage (D5 or D6) are required. PMID:28050955

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

    PubMed

    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.

  4. Quantitative comparison of multiframe data association techniques for particle tracking in time-lapse fluorescence microscopy.

    PubMed

    Smal, Ihor; Meijering, Erik

    2015-08-01

    Biological studies of intracellular dynamic processes commonly require motion analysis of large numbers of particles in live-cell time-lapse fluorescence microscopy imaging data. Many particle tracking methods have been developed in the past years as a first step toward fully automating this task and enabling high-throughput data processing. Two crucial aspects of any particle tracking method are the detection of relevant particles in the image frames and their linking or association from frame to frame to reconstruct the trajectories. The performance of detection techniques as well as specific combinations of detection and linking techniques for particle tracking have been extensively evaluated in recent studies. Comprehensive evaluations of linking techniques per se, on the other hand, are lacking in the literature. Here we present the results of a quantitative comparison of data association techniques for solving the linking problem in biological particle tracking applications. Nine multiframe and two more traditional two-frame techniques are evaluated as a function of the level of missing and spurious detections in various scenarios. The results indicate that linking techniques are generally more negatively affected by missing detections than by spurious detections. If misdetections can be avoided, there appears to be no need to use sophisticated multiframe linking techniques. However, in the practically likely case of imperfect detections, the latter are a safer choice. Our study provides users and developers with novel information to select the right linking technique for their applications, given a detection technique of known quality.

  5. Developmental dynamics of IMSI-derived embryos: a time-lapse prospective study.

    PubMed

    Knez, Katja; Tomazevic, Tomaz; Vrtacnik-Bokal, Eda; Virant-Klun, Irma

    2013-08-01

    Because sperm vacuoles were marked as zones without chromatin in the sperm nucleus, which may reflect underlying chromosomal or DNA defects, this study considered whether they influence the morphology and dynamics of early developmental events in preimplantation embryos. Oocytes were injected with spermatozoa of four classes, according to the number and size of vacuoles at ×6000 magnification, and derived embryos were observed under time-lapse microscopy. For each embryo, the times of pronuclei appearance and disappearance and the first, second and third divisions were determined and related to its respective class of injected spermatozoa and its developmental stage. Embryos arising from normal class-I spermatozoa (without vacuoles) reached the 4-cell stage significantly earlier than embryos developed from class-IV spermatozoa (with large vacuoles and other abnormalities) (P=0.012). Blastocysts from class-I spermatozoa required the shortest mean time for all developmental events in comparison with blastocysts from spermatozoa of other classes (with vacuoles). Blastocysts also showed significantly earlier first division than arrested embryos in embryos arising from class-I spermatozoa (P=0.033). An insight into the developmental dynamics of embryo development according to morphology and head vacuoles of injected spermatozoa in morphologically selected sperm-derived embryos was observed for the first time.

  6. How much have we learned from time-lapse in clinical IVF?

    PubMed

    Castelló, D; Motato, Y; Basile, N; Remohí, J; Espejo-Catena, M; Meseguer, M

    2016-10-01

    Can the time-lapse system (TLS) identify the best embryo for transfer? Although there are several studies that support this hypothesis, more research is required to improve the quality of the current evidence and also to assess live birth rate, miscarriage, stillbirth or clinical pregnancy in order to choose between a TLS or conventional incubation. In addition, although some authors report on effectiveness and safety in the use of TLS monitoring of embryo development in vitro, other authors that have not found relevant differences between the two systems for the culture and subsequence embryo selection. On the other hand, TLS has emerged as a novel technology and has been introduced into clinical practice in many laboratories to perform embryo morphology evaluation and study developmental kinetics in ART. However, most studies only assess blastocyst formation or implantation rate as the primary end-point and additional data are required, for example, about live birth, monozygotic twinning rates and health problems. Furthermore, the features of populations studies are varied; for example, female and male age, seminal characteristics and female factor. The embryo culture conditions and culture medium used also vary. For this review, a search of PubMed was conducted to retrieve relevant studies regarding use of TLS in embryo incubation and selection, and compare them with standard embryo culture and evaluation. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Time-lapse crosswell seismic and VSP monitoring of injected CO2 in a brine aquifer

    NASA Astrophysics Data System (ADS)

    Daley, Thomas M.; Myer, Larry R.; Peterson, J. E.; Majer, E. L.; Hoversten, G. M.

    2008-06-01

    Seismic surveys successfully imaged a small scale CO2 injection (1,600 ton) conducted in a brine aquifer of the Frio Formation near Houston, Texas. These time-lapse borehole seismic surveys, crosswell and vertical seismic profile (VSP), were acquired to monitor the CO2 distribution using two boreholes (the new injection well and a pre-existing well used for monitoring) which are 30 m apart at a depth of 1,500 m. The crosswell survey provided a high-resolution image of the CO2 distribution between the wells via tomographic imaging of the P-wave velocity decrease (up to 500 m/s). The simultaneously acquired S-wave tomography showed little change in S-wave velocity, as expected for fluid substitution. A rock physics model was used to estimate CO2 saturations of 10 20% from the P-wave velocity change. The VSP survey resolved a large (˜70%) change in reflection amplitude for the Frio horizon. This CO2 induced reflection amplitude change allowed estimation of the CO2 extent beyond the monitor well and on three azimuths. The VSP result is compared with numerical modeling of CO2 saturations and is seismically modeled using the velocity change estimated in the crosswell survey.

  8. Protein Kinase A Catalytic Subunit Primed for Action: Time-Lapse Crystallography of Michaelis Complex Formation.

    PubMed

    Das, Amit; Gerlits, Oksana; Parks, Jerry M; Langan, Paul; Kovalevsky, Andrey; Heller, William T

    2015-12-01

    The catalytic subunit of the cyclic AMP-dependent protein kinase A (PKAc) catalyzes the transfer of the γ-phosphate of bound Mg2ATP to a serine or threonine residue of a protein substrate. Here, time-lapse X-ray crystallography was used to capture a series of complexes of PKAc with an oligopeptide substrate and unreacted Mg2ATP, including the Michaelis complex, that reveal important geometric rearrangements in and near the active site preceding the phosphoryl transfer reaction. Contrary to the prevailing view, Mg(2+) binds first to the M1 site as a complex with ATP and is followed by Mg(2+) binding to the M2 site. Concurrently, the target serine hydroxyl of the peptide substrate rotates away from the active site toward the bulk solvent, which breaks the hydrogen bond with D166. Lastly, the serine hydroxyl of the substrate rotates back toward D166 to form the Michaelis complex with the active site primed for phosphoryl transfer.

  9. Automated focusing of nuclei for time lapse experiments on single cells using holographic optical tweezers.

    PubMed

    Eriksson, Emma; Engström, David; Scrimgeour, Jan; Goksör, Mattias

    2009-03-30

    Experiments on single cells are currently gaining more and more interest. Single cell studies often concerns the spatio-temporal distribution of fluorescent proteins inside living cells, visualized using fluorescence microscopy. In order to extract quantitative information from such experiments it is necessary to image the sample with high spatial and temporal resolution while keeping the photobleaching to a minimum. The analysis of the spatial distribution of proteins often requires stacks of images at each time point, which exposes the sample to unnecessary amounts of excitation light. In this paper we show how holographic optical tweezers combined with image analysis can be used to optimize the axial position of trapped cells in an array in order to bring the nuclei into a single imaging plane, thus eliminating the need for stacks of images and consequently reducing photobleaching. This allows more images to be collected, as well as increasing the time span and/or the time resolution in time lapse studies of single cells.

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

    SciTech Connect

    RUCKER DF; FINK JB; LOKE MH; MYERS DA

    2009-11-05

    Highly industrialized areas pose significant challenges for surface based electrical resistivity characterization and monitoring due to the high degree of metallic infrastructure. The infrastructure is typically several orders of magnitude more conductive than the desired targets, preventing the geophysicist from obtaining a clear picture of the subsurface. These challenges may be minimized if steel-cased wells are used as long electrodes. We demonstrate a method of using long electrodes in a complex nuclear waste facility to monitor a simulated leak from an underground storage tank. The leak was simulated by injecting high conductivity fluid in a perforated well and the resistivity measurements were made before and after the leak test. The data were processed in four dimensions, where a regularization procedure was applied in both the time and space domains. The results showed a lowered resistivity feature develop south of the injection site. The time lapsed regularization parameter had a strong influence on the differences in inverted resistivity between the pre and post datasets, potentially making calibration of the results to specific hydrogeologic parameters difficult.

  11. Time lapse seismic signal analysis for Cranfield, MS, EOR and CCS site

    NASA Astrophysics Data System (ADS)

    Ditkof, J.; Caspari, E.; Pevzner, R.; Urosevic, M.; Meckel, T. A.; Hovorka, S. D.

    2012-12-01

    The Cranfield field located in Southwest Mississippi is an EOR and CCS project which has been under continuous CO2 injection by Denbury Onshore LLC since 2008. To date, more than 3 million tons of CO2 remain in the subsurface. In 2007 and 2010, 3D seismic surveys were shot and an initial 4D seismic response was characterized showing coherent amplitude anomalies in some areas which received large amounts of CO2, but not in others. Previous work used Gassmann fluid substitution at two different wells, 31F-2 observation well and the 28-1 injection well to predict a post-injection saturation curves and acoustic impedance change through the reservoir. Since this writing, a second injection well, the 44-2 well, was added to the analysis to improve the practically unconstrained inversion. The two seismic volumes were cross-equalized with an appropriate correlation coefficient through well ties. Acoustic impedance inversions were carried out on each survey resulting with higher acoustic impedance changes than predicted by Gassmann for the 28-1 and 44-2 injection wells. The time-lapse acoustic impedance however is similar to the difference calculated from a time-delay along a horizon below the reservoir.

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

    PubMed Central

    Leacock, William B.; Eby, Lisa A.; Stanford, Jack A.

    2016-01-01

    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. PMID:27326378

  13. Investigating motion blur and temporal aliasing from time-lapse electrical resistivity

    NASA Astrophysics Data System (ADS)

    Rucker, Dale

    2014-12-01

    Geophysical monitoring through time-lapsed resistivity imaging is investigated to determine detrimental effects resulting from temporal smear. Temporal smear can be divided into motion blur and temporal aliasing, with motion blur attributed to an extended sample integration time relative to the velocity of a moving target, thus giving rise to reproduced targets that are distorted versions of the real target shape. Aliasing results from undersampling across time and may give a discontinuous movement. The degree to which each aspect of smear affects target properties described by spatial moment analysis depends on the spatial resolution of the imaging method and the degree to which temporal degradation is applied. For synthetic models with relatively high spatial resolution, aliasing effects were slight except in cases where the minimal number of snapshots was acquired to understand the end state condition of the target. Motion blur, on the other hand, had progressive detrimental effects with each level of additional smearing. For field data acquired during subsurface injection with a lower resolution array, the damaging effects from motion blur and temporal aliasing were equivalent. Both aspects showed progressive degeneration of spatial moments with each level of degradation. To combat this problem in the short term, it is recommended to acquire resistivity data as rapidly as possible and sacrifice some spatial resolution to enhance temporal resolution. In the future, there may be methods adopted from motion photography to deblur target motion by using the point spread function. Aliasing, however, can only be solved through continuous sampling.

  14. Time-lapse live imaging of clonally related neural progenitor cells in the developing zebrafish forebrain.

    PubMed

    Dong, Zhiqiang; Wagle, Mahendra; Guo, Su

    2011-04-06

    Precise patterns of division, migration and differentiation of neural progenitor cells are crucial for proper brain development and function. To understand the behavior of neural progenitor cells in the complex in vivo environment, time-lapse live imaging of neural progenitor cells in an intact brain is critically required. In this video, we exploit the unique features of zebrafish embryos to visualize the development of forebrain neural progenitor cells in vivo. We use electroporation to genetically and sparsely label individual neural progenitor cells. Briefly, DNA constructs coding for fluorescent markers were injected into the forebrain ventricle of 22 hours post fertilization (hpf) zebrafish embryos and electric pulses were delivered immediately. Six hours later, the electroporated zebrafish embryos were mounted with low melting point agarose in glass bottom culture dishes. Fluorescently labeled neural progenitor cells were then imaged for 36 hours with fixed intervals under a confocal microscope using water dipping objective lens. The present method provides a way to gain insights into the in vivo development of forebrain neural progenitor cells and can be applied to other parts of the central nervous system of the zebrafish embryo.

  15. Time-lapse microscopy studies of bystander effects induced by photosensitization

    NASA Astrophysics Data System (ADS)

    Chen, Yin-Chu; Redmond, Robert W.

    2006-02-01

    Reactive oxygen species (ROS) are involved in the pathogenesis of many critical diseases and are also utilized as cytotoxic agents in a variety of treatments for eradication of diseased tissue, including cancer. Oxidative stress ensues when the level of ROS in a system exceeds the antioxidant capacity. Oxidative stress can have local (direct) and long-range (bystander) effects in cells and tissue and this research was carried out to determine the spatial and temporal nature of the photosensitized bystander effect using time-lapse fluorescence microscopy. By initiating photosensitization in only a portion of the microscopic imaging field it was possible to differentiate direct from bystander effects in EMT-6 murine breast cancer cells in 6-well plates. Elevated ROS levels are seen immediately following photodynamic treatment in direct cells with a delayed increase in oxidative stress observed in bystander cells. Cytotoxicity is also seen at earlier times in direct cells and occurs in bystander cells in a delayed fashion. These studies confirm the existence of a bystander effect following photosensitization and implicate mediators capable of diffusing in an intercellular manner from directly photosensitized cells to bystander cells and also implicate increased oxidative stress as a mechanistic factor in generating damage in bystander cells.

  16. Cellular dynamics during early barley pollen embryogenesis revealed by time-lapse imaging

    PubMed Central

    Daghma, Diaa Eldin S.; Hensel, Goetz; Rutten, Twan; Melzer, Michael; Kumlehn, Jochen

    2014-01-01

    Plants display a remarkable capacity for cellular totipotency. An intriguing and useful example is that immature pollen cultured in vitro can pass through embryogenic development to form haploid or doubled haploid plants. However, a lack of understanding the initial mechanisms of pollen embryogenesis hampers the improvement and more effective and widespread employment of haploid technology in plant research and breeding. To investigate the cellular dynamics during the onset of pollen embryogenesis, we used time-lapse imaging along with transgenic barley expressing nuclear localized Green Fluorescent Protein. The results enabled us to identify nine distinct embryogenic and non-embryogenic types of pollen response to the culture conditions. Cell proliferation in embryogenic pollen normally started via a first symmetric mitosis (54.3% of pollen observed) and only rarely did so via asymmetric pollen mitosis I (4.3% of pollen observed). In the latter case, proliferation generally originated from the vegetative-like cell, albeit the division of the generative-like cell was observed in few types of pollen. Under the culture conditions used, fusion of cell nuclei was the only mechanism of genome duplication observed. PMID:25538715

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

    PubMed

    Hodson, Gordon; Earle, Megan

    2017-08-30

    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.

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

    USGS Publications Warehouse

    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.

  19. Magnetic resonance imaging (MRI) of a cookie in comparison with time-lapse photographic analysis (TLPA) during baking process.

    PubMed

    Hong, S W; Yan, Z Y; Otterburn, M S; McCarthy, M J

    1996-01-01

    Magnetic Resonance Imaging (MRI) has been used to study the baking of a cookie. The structural and dynamic changes occurring during baking have been monitored, including changes in the internal moisture saturations and distribution. The images reveal the moisture distribution is initially uniform, and during baking a gradient in moisture develops from the interior to the edge. Changes in physical dimensions calculated from the data are consistent with those obtained from time-lapsed photography.

  20. A Versatile Time-Lapse Camera System Developed by the Hawaiian Volcano Observatory for Use at Kilauea Volcano, Hawaii

    USGS Publications Warehouse

    Orr, Tim R.; Hoblitt, Richard P.

    2008-01-01

    Volcanoes can be difficult to study up close. Because it may be days, weeks, or even years between important events, direct observation is often impractical. In addition, volcanoes are often inaccessible due to their remote location and (or) harsh environmental conditions. An eruption adds another level of complexity to what already may be a difficult and dangerous situation. For these reasons, scientists at the U.S. Geological Survey (USGS) Hawaiian Volcano Observatory (HVO) have, for years, built camera systems to act as surrogate eyes. With the recent advances in digital-camera technology, these eyes are rapidly improving. One type of photographic monitoring involves the use of near-real-time network-enabled cameras installed at permanent sites (Hoblitt and others, in press). Time-lapse camera-systems, on the other hand, provide an inexpensive, easily transportable monitoring option that offers more versatility in site location. While time-lapse systems lack near-real-time capability, they provide higher image resolution and can be rapidly deployed in areas where the use of sophisticated telemetry required by the networked cameras systems is not practical. This report describes the latest generation (as of 2008) time-lapse camera system used by HVO for photograph acquisition in remote and hazardous sites on Kilauea Volcano.

  1. Exploring the use patterns of a mobile health application for alcohol addiction before the initial lapse after detoxification.

    PubMed

    Chih, Ming-Yuan

    2014-01-01

    How patients used Addiction-Comprehensive Health Enhancement Support System (A-CHESS)1, a mobile health intervention, while quitting drinking is worthy exploring. This study is to explore A-CHESS use patterns prior to the initial lapse reported after discharge from inpatient detoxification programs. 142 patients with alcohol addiction from two treatment agencies in the U.S. were included. A comprehensive set of A-CHESS use measures were developed based on a three-level system use framework and three A-CHESS service categories. In latent profile analyses, three A-CHESS system use patterns-inactive, passive, and active users-were found. Compared to the passive users (with the highest chance of the initial lapse), the active users (with the lowest chance of such behavior) participated more in online social activities, used more sessions, viewed more pages, and used A-CHESS longer. However, the chances of the initial lapse between A-CHESS user profiles were not statistically different. Implications of this finding were provided.

  2. puffMarker: A Multi-Sensor Approach for Pinpointing the Timing of First Lapse in Smoking Cessation

    PubMed Central

    Saleheen, Nazir; Ali, Amin Ahsan; Hossain, Syed Monowar; Sarker, Hillol; Chatterjee, Soujanya; Marlin, Benjamin; Ertin, Emre; al’Absi, Mustafa; Kumar, Santosh

    2015-01-01

    Recent researches have demonstrated the feasibility of detecting smoking from wearable sensors, but their performance on real-life smoking lapse detection is unknown. In this paper, we propose a new model and evaluate its performance on 61 newly abstinent smokers for detecting a first lapse. We use two wearable sensors — breathing pattern from respiration and arm movements from 6-axis inertial sensors worn on wrists. In 10-fold cross-validation on 40 hours of training data from 6 daily smokers, our model achieves a recall rate of 96.9%, for a false positive rate of 1.1%. When our model is applied to 3 days of post-quit data from 32 lapsers, it correctly pinpoints the timing of first lapse in 28 participants. Only 2 false episodes are detected on 20 abstinent days of these participants. When tested on 84 abstinent days from 28 abstainers, the false episode per day is limited to 1/6. PMID:26543927

  3. Enhanced imaging of CO2 at the Ketzin storage site: Inversion of 3D time-lapse seismic data

    NASA Astrophysics Data System (ADS)

    Gil, M.; Götz, J.; Ivanova, A.; Juhlin, C.; Krawczyk, C. M.; Lüth, S.; Yang, C.

    2012-04-01

    The Ketzin test site, located near Berlin, is Europe's longest-operating on-shore CO2 storage site. As of December 2011, more than 56,000 tons of food grade CO2 has been injected since June 2008 in an anticlinal structure of the Northeast German Basin. The target reservoir consists of porous, brine bearing sandstone units of the Upper Triassic Stuttgart Formation at approximately 630 to 650 m depth. In order to enhance the understanding of the structural geometry of the site and to investigate the extension of the CO2-plume, several geophysical monitoring methods are being applied at Ketzin, among these are active seismic measurements, geoelectrics and borehole measurements. Among the various seismic techniques (e.g. 2D reflection surveys, crosshole tomography, Vertical Seismic Profiling, 2D- and 3D-Moving Source Profiling) employed at this pilot site, 3D time-lapse reflection surveys are an important component. The baseline 3D survey was acquired in 2005 and the first repeat measurements were performed in 2009 after injection of about 22,000 tons of CO2. The second repeat survey is planned to be carried out in fall 2012. These measurements allow the time-lapse signature of the injected CO2 to be imaged. The time-lapse amplitude variation attributed to the injected CO2 in the reservoir matches, considering detection limits of seismic surface measurements, the expected distribution of the CO2 plume derived from reservoir simulations. Previous attempts towards a quantitative interpretation were based on integrative considerations of different types of geophysical measurements using strict assumptions and characterized by large error bars. In order to increase the resolution and reliability of the data and to improve estimation of rock properties and especially to enhance the imaging resolution of the CO2-plume, the time-lapse 3D seismic data have now been inverted for seismic impedances with different methods, which is the focus of this presentation. One difficulty

  4. Uncertainties in rock pore compressibility and effects on time lapse seismic modeling - An application to Norne field

    NASA Astrophysics Data System (ADS)

    Suman, A.; Mukerji, T.

    2009-12-01

    Time lapse seismic has evolved as an important diagnostic tool in efficient reservoir characterization and monitoring. A typical step is modeling of seismic velocities, which can provide information on variation of pore pressure and saturation inside the reservoir. Using the data of Norne field, we have made a rock physics model and shown how uncertainties in rock pore compressibility (Cpp) can cause pitfalls in modeling of seismic velocities and associated time lapse seismic signatures. We derived pore compressibilities from well logs and used different pore compressibility for different zones. We start with the rock physics modeling of Norne field based on the well log data. We then present examples of sensitivity analyses on rock pore compressibility using flow simulation and velocity modeling based on the Norne field dataset. The Norne field is located in the southern part of the Nordland II area in the Norwegian Sea. It has 29 producer and 10 injector wells. The rocks within the Norne reservoir are of Late Triassic to Middle Jurassic age. The geological model consists of five reservoir zones. They are Garn, Not, Ile, Tofte and Tilje. Well logs of nine different wells have been considered for this study. These logs consist of porosity, volume of shale, saturations, sonic log and density. Well log data are analyzed for relationships among Vp, Vs, porosity, density and lithology. The basis of our approach is to relate elastic moduli and porosity near the well (based on the well log data) and use this relation to populate away from the well. Dvorkin’s unconsolidated sand model is used which relates the elastic moduli of high porosity sediments to porosity, mineralogy and effective pressure. Hertz-Mindlin contact theory is used to calculate the effective bulk and shear moduli of the rock frame at the critical porosity. Bulk and shear moduli of the rock frame having porosity below critical are calculated using the modified lower Hashin-Shtrikman bound. There are

  5. Time-lapse multi-offset imaging of infiltration in heterogeneous media

    NASA Astrophysics Data System (ADS)

    Mangel, A. R.; Moysey, S. M.

    2011-12-01

    Reflection profiling with ground-penetrating radar has proven to be a useful and efficient tool for mapping the shallow subsurface. Though less extensively used, multi-offset GPR data can provide additional information about EM wave velocity needed for depth registration of the images and estimation of water content. Such information is particularly useful for time-lapse imaging of hydrologic events, like infiltration. We present examples where time-lapse multi-offset GPR data are used to image changes in a sand tank during controlled flux infiltration experiments for the following conditions: 1) homogeneous sand, 2) sand with a buried land mine surrogate, and 3) sand with an embedded thin layer of low permeability silica flour. The tank measures 1.5m x 1.5m x 0.8m and is filled with 0.6m of sand underlain by 0.2m of gravel for drainage. A network of 15 soil moisture probes embedded in the sand measure water content continuously throughout the experiment at 10 second intervals. In each experiment we collected over 6000 traces of 900MHz multi-offset ground-penetrating radar data using an automated motion control system, yielding a multi-offset section across the tank every 20 seconds. The data are organized into a cube with axes of elapsed time since the start of infiltration, GPR travel time, and antenna offset. Conceptualizing the data as a cube allows us to evaluate the consistency of patterns in the multi-offset and common offset gathers. Clearly visible in all data are the airwave, groundwave, and bottom of tank reflection. Also present in the radar data is an arrival associated with the wetting front. Normal move-out analysis of arrivals for the homogeneous tank allow us to evaluate water content changes throughout the experiments, which were found to be in good agreement with results from HYDRUS-1D model simulations and the in-situ moisture probes. Arrivals associated with the land mine and thin layer are also observed in the additional experiments. Radar

  6. Clinical outcomes following selection of human preimplantation embryos with time-lapse monitoring: a systematic review.

    PubMed

    Kaser, Daniel J; Racowsky, Catherine

    2014-01-01

    Time-lapse monitoring (TLM) has emerged as a novel technology to perform semi-quantitative evaluation of embryo morphology and developmental kinetics in assisted reproduction. While this method has already been introduced into clinical practice in many laboratories, it is unclear whether it adds value to conventional morphology. Most studies only report blastocyst formation as the primary end-point. The aim of this systematic review is to provide a critical evaluation of the available studies that report clinical outcomes following embryo selection with TLM. A literature search in MEDLINE, Cochrane CENTRAL and ISI Web of Knowledge Science Citation Index was performed to identify studies that assess the clinical utility of kinetic markers for non-invasive selection of human embryos with high implantation potential. Only studies published before 31 December 2013 in the English language that report rates of implantation, clinical pregnancy or live birth were included. Two hundred and fifty-one studies were identified by database search and reference list review; only 13 met eligibility criteria and were included in this analysis. The following morphokinetic parameters were assessed: pronuclear dynamics and morphology (n = 3), duration of first cytokinesis and reappearance of nuclei after cleavage (n = 3), time to various cleavage stages (n = 5), duration of various cleavage stages (n = 6), duration of cleavage cycles and mitotic synchronicity (n = 6), and time to morula, blastocyst and hatching (n = 4). Five studies used combined parameter grading to generate a cumulative score, and two studies retrospectively compared implantation rates following embryo selection by conventional morphology alone or with the addition of a hierarchal time-lapse classification. While several studies suggest higher implantation rates for fast-cleaving embryos and those with a timely duration (i.e. all time points within the defined ranges) of the 2-cell and 3-cell stages, no single

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

    NASA Astrophysics Data System (ADS)

    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

  8. Oil Sands Characteristics and Time-Lapse and P-SV Seismic Steam Monitoring, Athabasca, Canada

    NASA Astrophysics Data System (ADS)

    Takahashi, A.; Nakayama, T.; Kashihara, K.; Skinner, L.; Kato, A.

    2008-12-01

    -injection. The differences of the seismic responses between the time-lapse seismic volumes can be quantitatively explained by P-wave velocity decrease of the oil sands layers due to steam-injection. In addition, the data suggests that a larger area would be influenced by pressure than temperature. We calculate several seismic attributes such as RMS values of amplitude difference, maximum cross correlations, and interval velocity differences. These attributes are integrated by using self-organization maps (SOM) and K-means methods. By this analysis, we are able to distinguish areas of steam chamber growth from transitional and non-affected areas. In addition, 3D P-SV converted-wave processing and analysis are applied on the second 3D data set (recorded with three-component digital sensor). Low Vp/Vs values in the P-SV volume show areas of steam chamber development, and high Vp/Vs values indicate transitional zones. Our analysis of both time-lapse 3D seismic and 3D P-SV data along with the rock physics model can be used to monitor qualitatively and quantitatively the rock property changes of the inter-well reservoir sands in the field.

  9. A microfluidic system for long-term time-lapse microscopy studies of mycobacteria.

    PubMed

    Golchin, Solmaz A; Stratford, James; Curry, Richard J; McFadden, Johnjoe

    2012-11-01

    Phenotypic heterogeneity in bacterial populations is thought to contribute to a number of important phenomena including sporulation and persistence. The latter has clinical implications in many diseases such as tuberculosis, where persistence of Mycobacterium tuberculosis within the human host is believed to be the root cause of latent tuberculosis and the ability of a minority population of cells to survive antibiotic exposure, despite being genetically identical to the bulk population that are killed. However, phenotypic variations caused by non-genetic mechanisms are difficult to study because of the transient nature of the persistent state and thereby the requirement to observe individual cells in real-time. Recently, microfluidics, combined with time-lapse microscopy, has become a powerful tool for studying population heterogeneity in bacteria. However, growth and replication of mycobacterial cells provide particular problems for the development of microfluidic systems due to their tendency to grow in three dimensions. We here describe a novel microfluidic device for the observation of growth and antibiotic killing in individual mycobacterial cells. We constructed a microfluidic device suitable for studying single cell behavior in mycobacteria. The growth of single cells of Mycobacterium smegmatis expressing green fluorescent protein was monitored using a confocal laser scanning microscope. Within the device M. smegmatis cells were tightly confined within a hydrogel matrix thus promoting planar growth. Cell growth and killing was observed in the device with dead cells highlighted by uptake of propidium iodide. Conclusions/Significance. We demonstrate that our device allows real-time analysis and long-term culture of single cells of mycobacteria, and is able to support the study of cell death during the application of antibiotics. The device will allow observation of individual cells' cell genealogy to be determined and direct observation of rare states, such

  10. Time-Lapse Retinal Ganglion Cell Dendritic Field Degeneration Imaged in Organotypic Retinal Explant Culture

    PubMed Central

    Johnson, Thomas V.; Oglesby, Ericka N.; Steinhart, Matthew R.; Cone-Kimball, Elizabeth; Jefferys, Joan; Quigley, Harry A.

    2016-01-01

    Purpose To develop an ex vivo organotypic retinal explant culture system suitable for multiple time-point imaging of retinal ganglion cell (RGC) dendritic arbors over a period of 1 week, and capable of detecting dendrite neuroprotection conferred by experimental treatments. Methods Thy1-YFP mouse retinas were explanted and maintained in organotypic culture. Retinal ganglion cell dendritic arbors were imaged repeatedly using confocal laser scanning microscopy. Maximal projection z-stacks were traced by two masked investigators and dendritic fields were analyzed for characteristics including branch number, size, and complexity. One group of explants was treated with brain derived neurotrophic factor (BDNF) and ciliary neurotrophic factor (CNTF) added to the culture media. Changes in individual dendritic fields over time were detected using pair-wise comparison testing. Results Retinal ganglion cells in mouse retinal explant culture began to degenerate after 3 days with 52.4% surviving at 7 days. Dendritic field parameters showed minimal change over 8 hours in culture. Intra- and interobserver measurements of dendrite characteristics were strongly correlated (Spearman rank correlations consistently > 0.80). Statistically significant (P < 0.001) dendritic tree degeneration was detected following 7 days in culture including: 40% to 50% decreases in number of branch segments, number of junctions, number of terminal branches, and total branch length. Scholl analyses similarly demonstrated a significant decrease in dendritic field complexity. Treatment of explants with BDNF+CNTF significantly attenuated dendritic field degeneration. Conclusions Retinal explant culture of Thy1-YFP tissue provides a useful model for time-lapse imaging of RGC dendritic field degeneration over a course of several days, and is capable of detecting neuroprotective amelioration of dendritic pruning within individual RGCs. PMID:26811145

  11. Time Lapse Gravity and Seismic Monitoring of CO2 Injection at the West Hastings Field, Texas

    NASA Astrophysics Data System (ADS)

    Ferguson, J. F.; Richards, T.; Klopping, F.; MacQueen, J.; Hosseini, S. A.

    2015-12-01

    Time lapse or 4D gravity and seismic reflection surveys are being conducted at the West Hastings Field near Houston, Texas to monitor the progress of CO2 injection. This Department of Energy supported CO2 sequestration experiment is conducted in conjunction with a Denbury Onshore, LLC tertiary recovery project. The reservoir is at a depth of 1.8 km in the Oligocene Frio sands and has been produced since the 1930s. Goals are an accounting and mapping of the injected CO2 and to determine if migration occurs along intra-reservoir faults. An integrated interpretation of the geophysical surveys will be made together with well logs and engineering data. Gravity monitoring of water versus gas replacement has been very successful, but liquid phase CO2 monitoring is problematic due to the smaller density contrast with respect to oil and water. This reservoir has a small volume to depth ratio and hence only a small gravity difference signal is expected on the surface. New borehole gravity technology introduced by Micro-g-Lacoste can make gravity measurements at near reservoir depths with a much higher signal to noise ratio. This method has been successfully evaluated on a simulation of the Hastings project. Field operations have been conducted for repeated surface and borehole gravity surveys beginning in 2013. The surface survey of 95 stations covers an area of 3 by 5 km and 22 borehole gravity logs are run in the interval above the Frio formation. 4D seismic reflection surveys are being made at 6 month intervals on the surface and in 3 VSP wells. CO2 injection into the targeted portion of the reservoir only began in early 2015 and monitoring will continue into 2017. To date only the baseline reservoir conditions have been assessed. The overall success of the gravity monitoring will not be determined until 2017.

  12. Time Lapse Storey Building Early Monitoring Based on Rapid Seismic Response Analysis in Indonesia

    NASA Astrophysics Data System (ADS)

    Julius, A. M.

    2015-12-01

    Within the last decade, advances in the acquisition, processing and transmission of data from seismic monitoring has contributed to the growth in the number structures instrumented with such systems. An equally important factor for such growth can be attributed to the demands by stakeholders to find rapid answers to important questions related to the functionality or state of "health" of structures during and immediately of a seismic events. Consequently, this study aims to monitor the storey building based on seismic response i. e. earthquake and tremor analysis at short time lapse using accelerographs data. This study used one of storey building (X) in Jakarta city that suffered the effects of Kebumen earthquake January 25th 2014, Pandeglang earthquake July 9th 2014, and Lebak earthquake November 8th 2014. Tremors used in this study are tremors after the three following earthquakes. Data processing used to determine peak ground acceleration (PGA), peak ground velocity (PGV), peak ground displacement (PGD), spectral acceleration (SA), spectral velocity (SV), spectral displacement (SD), A/V ratio, acceleration amplification and effective duration (te). Then determine the natural frequency (f0) and peak of H/V ratio using H/V ratio method. The earthquakes data processing result shows the value of peak ground motion, spectrum response, A/V ratio and acceleration amplification increases with height, while the value of the effective duration decreases. Then, tremors data processing result one month after each earthquakes shows the natural frequency of building in constant value. Increasing of peak ground motion, spectrum response, A/V ratio, acceleration amplification, then decrease of effective duration following the increase of building floors shows that the building construction supports the increasing of shaking and strongly influenced by local site effect. The constant value of building natural frequency shows the building still in good performance. This

  13. Assessing spatial and temporal snowpack evolution and melt with time-lapse photography

    NASA Astrophysics Data System (ADS)

    Bush, C. E.; Ewers, B. E.; Beverly, D.; Speckman, H. N.; Hyde, K.; Ohara, N.

    2015-12-01

    Snowpack supplies and stores water for many ecosystems of the greater Rocky Mountain region. In Wyoming the snowpack supplies water to 18 states east and west of the Continental Divide. The spatial variability in physical and biological processes creates a heterogeneous pattern of snow evolution. Understanding these processes within individual plots and throughout the entire watershed increases the predictive power of snow distribution, melt rates and contribution to streamflow. However, on site sampling of snow can be an expensive and arduous process. The objective of this experiment was to quantify spatial and temporal patterns of snowpack evolution and melt rates while minimizing perturbations to snowpack through the use of time-lapse photography via trail cameras. Field cameras were assessed as a method to quantify snow depths throughout the 120 ha No Name watershed at approximately 3000 m elevation in central Wyoming. RGB trail cameras were installed at three systematically chosen sites within the watershed to correlate physical and biological drivers of snow distribution. Five stakes were placed in each site in heterogeneous spots that remained in the frame of the camera. Stakes were divided into five centimeter increments, alternating black and white bars, with red bars denoting each half meter. Images were then taken at two-hour intervals over a period of three-months and analyzed with the ImageJ program. Snowpack distributions, as well as melt rates, were variable at both the plot and watershed scales. Meteorological and physical drivers, primarily topography and radiation, accounted for the greatest variability when comparing among plot across the watershed; however, LAI and soil and air temperature were the most significant drivers within plots. Snow-melt rate increased as soils and course woody debris became exposed increasing ground and soil temperature. These data will improve process model predictions of streamflow from the watershed.

  14. Sensitivity of the atmospheric lapse rate to solar cloud absorption in a radiative-convective model

    NASA Astrophysics Data System (ADS)

    Erlick, Carynelisa; Ramaswamy, V.

    2003-08-01

    Previous radiative-convective model studies of the radiative forcing due to absorbing aerosols such as soot and dust have revealed a strong dependence on the vertical distribution of the absorbers. In this study, we extend this concept to absorption in cloud layers, using a one-dimensional radiative-convective model employing high, middle, and low cloud representations to investigate the response of the surface temperature and atmospheric lapse rate to increases in visible cloud absorption. The visible single-scattering albedo (ssa) of the clouds is prescribed, ranging from 1.0 to 0.6, where 0.99 is the minimum that would be expected from the presence of absorbing aerosols within the cloud drops on the basis of recent Monterey Area Ship Track (MAST) Experiment case studies. Simulations are performed with respect to both a constant cloud optical depth and an increasing cloud optical depth and as a function of cloud height. We find that increases in solar cloud absorption tend to warm the troposphere and surface and stabilize the atmosphere, while increases in cloud optical depth cool the troposphere and surface and slightly stabilize the atmosphere between the low cloud top and surface because of the increase in surface cooling. In the absence of considerations involving microphysical or cloud-climate feedbacks, we find that two conditions are required to yield an inversion from a solar cloud absorption perturbation: (1) The solar absorption perturbation must be included throughout the tropospheric clouds column, distributing the solar heating to higher altitudes, and (2) the ssa of the clouds must be ≤0.6, which is an unrealistically low value. The implication is that there is very little possibility of significant stabilization of the global mean atmosphere due to perturbation of cloud properties given current ssa values.

  15. Time-lapse 3-D seismic imaging of shallow subsurface contaminant flow.

    PubMed

    McKenna, J; Sherlock, D; Evans, B

    2001-12-01

    This paper presents a physical modelling study outlining a technique whereby buoyant contaminant flow within water-saturated unconsolidated sand was remotely monitored utilizing the time-lapse 3-D (TL3-D) seismic response. The controlled temperature and pressure conditions, along with the high level of acquisition repeatability attainable using sandbox physical models, allow the TL3-D seismic response to pore fluid movement to be distinguished from all other effects. TL3-D seismic techniques are currently being developed to monitor hydrocarbon reserves within producing reservoirs in an endeavour to improve overall recovery. However, in many ways, sandbox models under atmospheric conditions more accurately simulate the shallow subsurface than petroleum reservoirs. For this reason, perhaps the greatest application for analogue sandbox modelling is to improve our understanding of shallow groundwater and environmental flow mechanisms. Two fluid flow simulations were conducted whereby air and kerosene were injected into separate water-saturated unconsolidated sand models. In both experiments, a base 3-D seismic volume was recorded and compared with six later monitor surveys recorded while the injection program was conducted. Normal incidence amplitude and P-wave velocity information were extracted from the TL3-D seismic data to provide visualization of contaminant migration. Reflection amplitudes displayed qualitative areal distribution of fluids when a suitable impedance contrast existed between pore fluids. TL3-D seismic reflection tomography can potentially monitor the change in areal distribution of fluid contaminants over time, indicating flow patterns. However, other research and this current work have not established a quantifiable relationship between either normal reflection amplitudes and attenuation and fluid saturation. Generally, different pore fluids will have unique seismic velocities due to differences in compressibility and density. The predictable

  16. Microfluidics-integrated time-lapse imaging for analysis of cellular dynamics.

    PubMed

    Albrecht, Dirk R; Underhill, Gregory H; Resnikoff, Joshua; Mendelson, Avital; Bhatia, Sangeeta N; Shah, Jagesh V

    2010-06-01

    An understanding of the mechanisms regulating cellular responses has recently been augmented by innovations enabling the observation of phenotypes at high spatio-temporal resolution. Technologies such as microfluidics have sought to expand the throughput of these methods, although assimilation with advanced imaging strategies has been limited. Here, we describe the pairing of high resolution time-lapse imaging with microfluidic multiplexing for the analysis of cellular dynamics, utilizing a design selected for facile fabrication and operation, and integration with microscopy instrumentation. This modular, medium-throughput platform enables the long-term imaging of living cells at high numerical aperture (via oil immersion) by using a conserved 96-well, approximately 6 x 5 mm(2) imaging area with a variable input/output channel design chosen for the number of cell types and microenvironments under investigation. In the validation of this system, we examined fundamental features of cell cycle progression, including mitotic kinetics and spindle orientation dynamics, through the high-resolution parallel analysis of model cell lines subjected to anti-mitotic agents. We additionally explored the self-renewal kinetics of mouse embryonic stem cells, and demonstrate the ability to dynamically assess and manipulate stem cell proliferation, detect rare cell events, and measure extended time-scale correlations. We achieved an experimental throughput of >900 cells/experiment, each observed at >40x magnification for up to 120 h. Overall, these studies illustrate the capacity to probe cellular functions and yield dynamic information in time and space through the integration of a simple, modular, microfluidics-based imaging platform.

  17. Using electromagnetic conductivity imaging to generate time-lapse soil moisture estimates.

    NASA Astrophysics Data System (ADS)

    Huang, Jingyi; Scuderio, Elia; Corwin, Dennis; Triantafilis, John

    2015-04-01

    Irrigated agriculture is crucial to the agricultural productivity of the Moreno valley. To maintain profitability, more will need to be done by irrigators with less water, owing to competing demands from rapidly expanding urbanisation in southern California. In this regard, irrigators need to understand the spatial and temporal variation of soil moisture to discern inefficiencies. However, soil moisture is difficult to measure and monitor, unless a large bank of soil sensors are installed and at various depths in the profile. In order to value add to the limited amount of information, geophysical techniques, such as direct current resisivity (DCR) arrays are used to develop electrical resistivity images (ERI). Whilst successful the approach is time consuming and labour intensive. In this research we describe how equivalent data can be collected using a proximal sensing electromagnetic (EM) induction instrument (i.e. DUALEM-421) and inversion software (EM4Soil) to generate EM conductivity images (EMCI). Figure 1 shows the EMCI generated from DUALEM-421 data acquired at various days of a time-lapse experiment and including; day a) 0, b) 1, c) 2, d) 3, e) 5, f) 7 and g) 11. We calibrate the estimates of true electrical conductivity (sigma - mS/m) with volumetric moisture content and show with good accuracy the spatial and temporal variation of soil moisture status and over 12 day period. The results show clearly that the pivot sprinkler irrigation system is effective at providing sufficient amounts of water to the top 0.5 m of a Lucerne crop (i.e. red shaded areas of high sigma). However, in some places faulty sprinklers are evident owing to the lack of wetting (i.e. blue shaded areas of low sigma). In addition, and over time, our approach shows clearly the effect the Lucerne crop has in drying the soil profile and using the soil moisture.

  18. Public health response to a large-scale endoscopy infection control lapse in a nonhospital clinic

    PubMed Central

    Willmore, Jacqueline; Ellis, Edward; Etches, Vera; Labrecque, Lise; Osiowy, Carla; Andonov, Anton; McDermaid, Cameron; Majury, Anna; Achonu, Camille; Maher, Maurica; MacLean, Brenda; Levy, Isra

    2015-01-01

    OBJECTIVE: To determine whether transmission of blood-borne pathogens (BBPs) (hepatitis B virus [HBV], hepatitis C virus [HCV] and HIV) occurred as a result of endoscopy reprocessing failures identified during an inspection of a nonhospital endoscopy clinic in 2011. METHODS: The present analysis was a retrospective cohort study. Registered notification letters were mailed to 6992 patients who underwent endoscopy from 2002 to 2011 at one Canadian nonhospital endoscopy clinic, informing them of the infection control lapse and offering BBP testing. Multimedia communications and a telephone line supplemented notification. A retrospective study of patients with BBPs was performed with viral genetic testing and risk factor assessment for eligible patients. Risk for infection among patients whose procedure was within seven days of a known positive patient was compared with those whose procedure was performed more than seven days after a known postive patient. The seven-day period was selected as the period most likely to present a risk for transmission based on the documented cleaning procedures at the clinic and the available literature on virus survival. RESULTS: Ninety-five percent (6628 of 6992) of patients/estates were contacted and 5042 of 6728 (75%) living patients completed BBP testing. Three were newly diagnosed with HBV and 14 with HCV. Twenty-three and 48 tested positive for previously known HBV or HCV, respectively, 367 were immune to HBV due to natural infection and one was immune to HBV due to immunization. None tested positive for HIV. Sequencing did not reveal any relationships among the 46 unique case patients with viral genetic test results available. Ninety-three percent of patients reported alternative risk factors for BBP. An increased risk for infection among those who underwent a procedure within seven days of a known HBV or HCV case was not demonstrated. CONCLUSIONS: Endoscopy reprocessing failures were not associated with an increased risk for BBP

  19. National survey on use of time-lapse imaging systems in IVF laboratories.

    PubMed

    Dolinko, Andrey V; Farland, L V; Kaser, D J; Missmer, S A; Racowsky, C

    2017-06-10

    Several time-lapse imaging (TLI) systems for non-invasive continuous monitoring of developing embryos are currently available. The present study explored the prevalence, means of acquisition, and clinical application of TLI systems in USA in vitro fertilization (IVF) laboratories. An online cross-sectional survey of 294 USA IVF laboratory directors was conducted in February and March 2016. Those directing more than one laboratory were asked to complete the survey for their home program and for their smallest laboratory by number of IVF/intracytoplasmic sperm injection (ICSI) cycle starts. Use of TLI was analyzed using logistic regression to calculate odds ratios (OR). Of 294 directors surveyed, 162 (55%) reported data on 204 laboratories. Thirty-five laboratories (17%) possessed at least one TLI system (median 2, interquartile range 1-4, total range 1-11). The more oocyte retrievals a laboratory performed annually, the more likely the laboratory was to possess a TLI system. Fifteen laboratories (43%) purchased their own systems, while others leased, loaned, or received donated systems. Twenty-five laboratories (71%) reported using TLI for embryo selection; all used TLI always, or usually, in combination with standard morphology evaluation. Twenty laboratories (80%) offered TLI to all patients. Some laboratories charged patients for TLI. Directors with TLI systems were more inclined to believe that TLI has value for embryo selection in clinical IVF. TLI system possession in USA IVF laboratories is low, although positively associated with the number of retrievals performed and with directors' opinions on the technology's utility. Over 70% of laboratories with TLI systems use them clinically, and less than half purchased their systems.

  20. A Local Index of Cloud Immersion in Tropical Forests Using Time-Lapse Photography

    NASA Astrophysics Data System (ADS)

    Bassiouni, M.; Scholl, M. A.

    2015-12-01

    Data on the frequency, duration and elevation of cloud immersion is essential to improve estimates of cloud water deposition in water budgets in cloud forests. Here, we present a methodology to detect local cloud immersion in remote tropical forests using time-lapse photography. A simple approach is developed to detect cloudy conditions in photographs within the canopy where image depth during clear conditions may be less than 10 meters and moving leaves and branches and changes in lighting are unpredictable. A primary innovation of this study is that cloudiness is determined from images without using a reference clear image and without minimal threshold value determination or human judgment for calibration. Five sites ranging from 600 to 1000 meters elevation along a ridge in the Luquillo Critical Zone Observatory, Puerto Rico were each equipped with a trail camera programmed to take an image every 30 minutes since March 2014. Images were classified using four selected cloud-sensitive image characteristics (SCICs) computed for small image regions: contrast, the coefficient of variation and the entropy of the luminance of each image pixel, and image colorfulness. K-means clustering provided reasonable results to discriminate cloudy from clear conditions. Preliminary results indicate that 79-94% (daytime) and 85-93% (nighttime) of validation images were classified accurately at one open and two closed canopy sites. The euclidian distances between SCICs vectors of images during cloudy conditions and the SCICs vector of the centroid of the cluster of clear images show potential to quantify cloud density in addition to immersion. The classification method will be applied to determine spatial and temporal patterns of cloud immersion in the study area. The presented approach offers promising applications to increase observations of low-lying clouds at remote mountain sites where standard instruments to measure visibility and cloud base may not be practical.

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

    SciTech Connect

    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.

  2. Extracting Time-Lapsed Velocity Changes From The Direct Arrival Of Ambient Noise Correlation Functions

    NASA Astrophysics Data System (ADS)

    Seats, K.; Lawrence, J. F.

    2013-12-01

    This study investigates methods for observing temporal subsurface velocity variations from ambient seismic noise, which provides an exciting opportunity to generate 4D tomographic images. In geologically active regions, the time lag of the ambient Noise Correlation Function (NCF) can change or migrate, reflecting associated changes in the subsurface velocity structure. Unfortunately, this time lag also reflects apparent velocity changes due to seasonal variations in the ambient seismic field as well. Recently, studies have begun observing these temporal variations in volcanic regions by analyzing the changes in the coda of the NCF, and attempting to spatially locate these changes though the examination of the complex scattering regime. Here, we examine time-lagged differences of the main arrival, with the signal to noise ratio of these NCFs being drastically improved by the development of the adaptive covariance filter (ACF). By utilizing velocity variations in these main arrivals, it becomes more straightforward to spatially locate these changes and understand their temporal resolution. We examine two case studies that have different spatial and temporal scales. First, we use all available data near the Yellowstone caldera, including permanent and temporary networks such as the USArray and NOISY projects. We attempt to correct for, and remove, seasonal velocity variations in the NCFs to directly observe decreased velocities at surface wave periods consistent with depths of the magma chamber beneath Yellowstone. Second, we use data from 2009-2011 around Piton de la Fournaise shield volcano on Réunion Island to observe temporal velocity variations associated with eruptive phases. We compare our results of the magnitude and location of these velocity variations to studies observing time-lapsed velocity changes from NCF coda waves.

  3. Time-lapse imaging reveals stereotypical patterns of Drosophila midline glial migration.

    PubMed

    Wheeler, Scott R; Pearson, Joseph C; Crews, Stephen T

    2012-01-15

    The Drosophila CNS midline glia (MG) are multifunctional cells that ensheath and provide trophic support to commissural axons, and direct embryonic development by employing a variety of signaling molecules. These glia consist of two functionally distinct populations: the anterior MG (AMG) and posterior MG (PMG). Only the AMG ensheath axon commissures, whereas the function of the non-ensheathing PMG is unknown. The Drosophila MG have proven to be an excellent system for studying glial proliferation, cell fate, apoptosis, and axon-glial interactions. However, insight into how AMG migrate and acquire their specific positions within the axon-glial scaffold has been lacking. In this paper, we use time-lapse imaging, single-cell analysis, and embryo staining to comprehensively describe the proliferation, migration, and apoptosis of the Drosophila MG. We identified 3 groups of MG that differed in the trajectories of their initial inward migration: AMG that migrate inward and to the anterior before undergoing apoptosis, AMG that migrate inward and to the posterior to ensheath commissural axons, and PMG that migrate inward and to the anterior to contact the commissural axons before undergoing apoptosis. In a second phase of their migration, the surviving AMG stereotypically migrated posteriorly to specific positions surrounding the commissures, and their final position was correlated with their location prior to migration. Most noteworthy are AMG that migrated between the commissures from a ventral to a dorsal position. Single-cell analysis indicated that individual AMG possessed wide-ranging and elaborate membrane extensions that partially ensheathed both commissures. These results provide a strong foundation for future genetic experiments to identify mutants affecting MG development, particularly in guidance cues that may direct migration. Drosophila MG are homologous in structure and function to the glial-like cells that populate the vertebrate CNS floorplate, and study

  4. The altitudinal temperature lapse rates applied to high elevation rockfalls studies in the Western European Alps

    NASA Astrophysics Data System (ADS)

    Nigrelli, Guido; Fratianni, Simona; Zampollo, Arianna; Turconi, Laura; Chiarle, Marta

    2017-02-01

    Temperature is one of the most important aspects of mountain climates. The relationships between air temperature and rockfalls at high-elevation sites are very important to know, but are also very difficult to study. In relation to this, a reliable method to estimate air temperatures at high-elevation sites is to apply the altitudinal temperature lapse rates (ATLR). The aims of this work are to quantify the values and the variability of the hourly ATLR and to apply this to estimated temperatures at high-elevation sites for rockfalls studies. To calculate ATLR prior the rockfalls, we used data acquired from two automatic weather stations that are located at an elevation above 2500 m. The sensors/instruments of these two stations are reliable because subjected to an accurate control and calibration once for year and the raw data have passed two automatic quality controls. Our study has yielded the following main results: (i) hourly ATLR increases slightly with increasing altitude, (ii) it is possible to estimate temperature at high-elevation sites with a good level of accuracy using ATLR, and (iii) temperature plays an important role on slope failures that occur at high-elevation sites and its importance is much more evident if the values oscillate around 0 °C with an amplitude of ±5 °C during the previous time-period. For these studies, it is not enough to improve the knowledge on air temperature, but it is necessary to develop an integrated knowledge of the thermal conditions of different materials involved in these processes (rock, debris, ice, water). Moreover, this integrated knowledge must be acquired by means of sensors and acquisition chains with known metrological traceability and uncertainty of measurements.

  5. Time-lapse imaging of self- and cross-pollinations in Brassica rapa

    PubMed Central

    Hiroi, Kenichiro; Sone, Mikako; Sakazono, Satomi; Osaka, Masaaki; Masuko-Suzuki, Hiromi; Matsuda, Tomoki; Suzuki, Go; Suwabe, Keita; Watanabe, Masao

    2013-01-01

    Background and Aims Pollination is an important process in the life cycle of plants and is the first step in bringing together the male and female gametophytes for plant reproduction. While pollination has been studied for many years, accurate knowledge of the morphological aspects of this process is still far from complete. This study therefore focuses on a morphological characterization of pollination, using time-series image analysis of self- and cross-pollinations in Brassica rapa. Methods Time-lapse imaging of pollen behaviour during self- and cross-pollinations was recorded for 90 min, at 1 min intervals, using a stereoscopic microscope. Using time-series digital images of pollination, characteristic features of pollen behaviours during self- and cross-pollinations were studied. Key Results Pollen exhibited various behaviours in both self- and cross-pollinations, and these were classified into six representative patterns: germination, expansion, contraction, sudden contraction, pulsation and no change. It is noteworthy that in ‘contraction’ pollen grains shrunk within a short period of 30–50 min, and in ‘pulsation’ repeated expansion and contraction occurred with an interval of 10 min, suggesting that a dehydration system is operating in pollination. All of the six patterns were observed on an individual stigma with both self- and cross-pollinations, and the difference between self- and cross-pollinations was in the ratios of the different behaviours. With regard to water transport to and from pollen grains, this occurred in multiple steps, before, during and after hydration. Thus, pollination is regulated by a combination of multiple components of hydration, rehydration and dehydration systems. Conclusions Regulated hydration of pollen is a key process for both pollination and self-incompatibility, and this is achieved by a balanced complex of hydration, dehydration and nutrient supply to pollen grains from stigmatic papilla cells. PMID:23644359

  6. Atypical embryo phenotypes identified by time-lapse microscopy: high prevalence and association with embryo development.

    PubMed

    Athayde Wirka, Kelly; Chen, Alice A; Conaghan, Joe; Ivani, Kristen; Gvakharia, Marina; Behr, Barry; Suraj, Vaishali; Tan, Lei; Shen, Shehua

    2014-06-01

    To characterize atypical dynamic embryo phenotypes identified by time-lapse microscopy, evaluate their prevalence, and determine their association with embryo development. Retrospective multicenter cohort study. Five IVF clinics in the United States. Sixty-seven women undergoing IVF treatment with 651 embryos. Embryo videos were retrospectively analyzed for atypical phenotypes. Identification of four groups of atypical embryo phenotypes: abnormal syngamy (AS), abnormal first cytokinesis (A1(cyt)), abnormal cleavage (AC), and chaotic cleavage (CC). Prevalence and association with embryo morphology and development potential were evaluated. A high prevalence of atypical phenotypes was observed among embryos: AS 25.1% (163/649), A1(cyt) 31.0% (195/639), AC 18% (115/639) and CC 15% (96/639). A high percentage of embryos with atypical phenotype(s) had good quality on day 3 (overall grade good or fair): AS 78.6% (70/89); A1(cyt) 79.7% (94/119), AC 86.4% (70/81), and CC 35.2% (19/54), but the blastocyst formation rates for these embryos were significantly lower compared with their respective control groups: AS 21.5% vs. 44.9%, A1(cyt) 21.7% vs. 44.6%, AC 11.7% vs. 43.1%, and CC 14.0% vs. 42.3%. Embryos exhibiting atypical phenotypes are highly prevalent in human embryos and show significantly lower developmental potential than control embryos. NCT01369446. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  7. Spatiotemporal Characteristics of Altitudinal Lapse Rate of Temperature in Mainland China

    NASA Astrophysics Data System (ADS)

    Li, Y.; Zeng, Z.; Zhao, L.; Piao, S.

    2014-12-01

    Quantitative evaluation of how mountain ecosystems respond to climate change requires accurate estimates of temperature at high altitudes. One approach to estimating highland temperature is by extrapolating temperatures from low altitudes, based on previous observations of the actual altitudinal lapse rate of temperature (γlocal). However, our understanding of γlocal is still very limited. Here, we use daily mean, maximum and minimum temperature (Tmean, Tmax, Tmin) data from 523 meteorological stations in mainland China to estimate the spatiotemporal patterns of γlocal. The mean γlocal across the whole country is 5.4 K km-1, with a daytime average of 5.0 K km-1 and a nighttime average of 5.6 K km-1. The patterns of γlocal for Tmean (γlocal(Tmean)) display: 1) a significant spatial difference between southern China and northern China (including the Qinghai-Tibet Plateau, p<0.05); 2) a distinct seasonal variation, with higher γlocal occurring in summer and lower occurring in winter in most regions. Interestingly, the seasonal variation for the Qinghai-Tibet Plateau is reversed, with γlocal being lower in summer and higher in winter. In addition, the spatial difference and seasonal variation of γlocal for Tmax and Tmin (γlocal(Tmax) and γlocal(T­min)) show similar patterns to γlocal(Tmean), but slightly diverge from each other. Our results demonstrate that the magnitude of γlocal obviously differs in regional distributions and seasonal variations, and may be a result of the interactions among temperature, atmospheric moisture content and solar radiation. To improve the accuracy of the extrapolation method requires spatial patterns of γlocal rather than just a constant universal value.

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

    USGS Publications Warehouse

    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.

  9. Time-lapse Imaging Reveals Stereotypical Patterns of Drosophila Midline Glial Migration

    PubMed Central

    Wheeler, Scott R.; Pearson, Joseph C.; Crews, Stephen T.

    2011-01-01

    The Drosophila CNS midline glia (MG) are multifunctional cells that ensheath and provide trophic support to commissural axons, and direct embryonic development by employing a variety of signaling molecules. These glia consist of two functionally distinct populations: the anterior MG (AMG) and posterior MG (PMG). Only the AMG ensheath axon commissures, whereas the function of the non-ensheathing PMG is unknown. The Drosophila MG have proven to be an excellent system for studying glial proliferation, cell fate, apoptosis, and axon-glial interactions. However, insight into how AMG migrate and acquire their specific positions within the axon-glial scaffold has been lacking. In this paper, we use time-lapse imaging, single-cell analysis, and embryo staining to comprehensively describe the proliferation, migration, and apoptosis of the Drosophila MG. We identified 3 groups of MG that differed in the trajectories of their initial inward migration: AMG that migrate inward and to the anterior before undergoing apoptosis, AMG that migrate inward and to the posterior to ensheath commissural axons, and PMG that migrate inward and to the anterior to contact the commissural axons before undergoing apoptosis. In a second phase of their migration, the surviving AMG stereotypically migrated posteriorly to specific positions surrounding the commissures, and their final position was correlated with their location prior to migration. Most noteworthy are AMG that migrated between the commissures from a ventral to a dorsal position. Single-cell analysis indicated that individual AMG possessed wide-ranging and elaborate membrane extensions that partially ensheathed both commissures. These results provide a strong foundation for future genetic experiments to identify mutants affecting MG development, particularly in guidance cues that may direct migration. Drosophila MG are homologous in structure and function to the glial-like cells that populate the vertebrate CNS floorplate, and study

  10. Variogram-based inversion of time-lapse electrical resistivity data: development and application to a thermal tracing experiment

    NASA Astrophysics Data System (ADS)

    Hermans, Thomas; Nguyen, Frédéric

    2015-04-01

    Electrical resistivity tomography (ERT) has become a popular imaging methodology in a broad range of applications given its large sensitivity to subsurface parameters and its relative simplicity to implement. More particularly, time-lapse ERT is now increasingly used for monitoring purposes in many contexts such as water content, permafrost, landslide, seawater intrusion, solute transport or heat transport experiments. Specific inversion schemes have been developed for time-lapse data sets. However, in contrast with static inversions for which many techniques including geostatistical, minimum support or structural inversion are commonly applied, most of the methodologies for time-lapse inversion still rely on non-physically based spatial and/or temporal smoothing of the parameters or parameter changes. In this work, we propose a time-lapse ERT inversion scheme based on the difference inversion scheme. We replace the standard smoothness-constraint regularization operator by the parameter change covariance matrix. The objective function can be expressed as ψdiff(Δm ) = ||Wd [d - d0 + f(m0)- f(m )]||2 + λ ||||C-Δ0m.5Δm ||||2 where Wd is the data weighting matrix, d and d0 are the data sets corresponding to the considered time-step and to the background, f() is the forward operator, m and m0 are the models corresponding to the considered time-step and to the background, Δm is the parameter change (resistivity), CΔm is the parameter change covariance matrix and λ the regularization parameter. This operator takes into account the correlation between changes in resistivity at different locations through a variogram computed using independent data (e.g., electromagnetic logs). It may vary for subsequent time-steps if the correlation length is time-dependent. The methodology is first validated and compared to the standard smoothness-constraint inversion using a synthetic benchmark simulating the injection of a conductive tracer into a homogeneous aquifer inducing

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  14. Time-lapse analysis of sparse 3D seismic data from the CO2 storage pilot site at Ketzin, Germany

    NASA Astrophysics Data System (ADS)

    Ivandic, M.; Yang, C.; Lüth, S.; Cosma, C.; Juhlin, C.

    2012-04-01

    Capture and geological storage of CO2 is considered to be a feasible method for reducing carbon emissions. In April 2004, a research pilot project in the German town of Ketzin started as the first onshore CO2 storage project in Europe. Injection started in June 2008 and until the latest repeat survey in February 2011 around 45 kilotons of CO2 had been injected into a saline aquifer at approximately 630-650 m depth. Different seismic methods, such as time-lapse Vertical Seismic Profiling (VSP), Crosswell, Moving Source Profiling (MSP) and surface seismics have been employed to detect and monitor changes in the reservoir. We present here time-lapse results from sparse 3D seismic surveying with a "star" geometry, i.e. with a radial distribution of acquisition profiles directed towards the approximate location of the injection well, which were acquired to link downhole surveys with full 3D surface seismic surveys. The main objectives of the sparse 3D surveys were (1) to identify changes in the seismic response related to the injection of CO2 between the repeat surveys and baseline survey and (2) to compare these results with those from the repeat 3D seismic survey. The results are consistent with the 3D seismic time-lapse studies over the injection site and show that the sparse 3D geometry can be used to qualitatively map the migration of the CO2 plume within the saline reservoir, as well as potential migration out of the reservoir rock at a significantly lower effort than the full 3D surveying. The latest repeat survey indicates preferential migration of the CO2 to the west. Both sparse 3D repeat surveys show that the CO2 is being confined within the aquifer, implying that there is no leakage into the caprock at the time of the repeat surveys. The same observation was obtained from the 3D dataset.

  15. Development and Preliminary Randomized Controlled Trial of a Distress Tolerance Treatment for Smokers With a History of Early Lapse

    PubMed Central

    2013-01-01

    Introduction: An inability to tolerate distress is a significant predictor of early smoking lapse following a cessation attempt. We conducted a preliminary randomized controlled trial to compare a distress tolerance (DT) treatment that incorporated elements of exposure-based therapies and Acceptance and Commitment Therapy to standard smoking cessation treatment (ST). Methods: Smokers with a history of early lapse in prior quit attempts received either DT (N = 27; 9 2-hr group and 6 50-min individual sessions) or ST (N = 22; 6 90-min group and 1 20-min individual session), plus 8 weeks of transdermal nicotine patch. Results: At the end of behavioral treatment, odds of abstinence among participants receiving DT were 6.46 times greater than among participants receiving ST (66.7% vs. 31.8%), equivalent to a medium- to large-effect size. Odds of abstinence for DT were still 1.73 times greater at 8 weeks, corresponding to a small- to medium-effect size, although neither this difference nor those at 13 and 26 weeks were statistically significant. Furthermore, of those who lapsed to smoking during the first week postquit, DT participants had more than 4 times greater odds of abstinence than ST participants at the end of treatment. Relative to ST, DT participants also reported a larger decrease in experiential avoidance, a hypothesized DT treatment mediator, prior to quit day. The trajectory of negative mood and withdrawal symptoms in DT differed from ST and was largely consistent with hypotheses. Conclusions: Reasons for the decrease in abstinence in DT after treatment discontinuation and suggestions for future research are discussed. PMID:23884317

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Blunted striatal response to monetary reward anticipation during smoking abstinence predicts lapse during a contingency-managed quit attempt

    PubMed Central

    Sweitzer, Maggie M.; Geier, Charles F.; Denlinger, Rachel; Forbes, Erika E.; Raiff, Bethany R.; Dallery, Jesse; McClernon, F.J.; Donny, Eric C.

    2017-01-01

    Rationale Tobacco smoking is associated with dysregulated reward processing within the striatum, characterized by hypersensitivity to smoking rewards and hyposensitivity to non-smoking rewards. This bias toward smoking reward at the expense of alternative rewards is further exacerbated by deprivation from smoking, which may contribute to difficulty maintaining abstinence during a quit attempt. Objective We examined whether abstinence-induced changes in striatal processing of rewards predicted lapse likelihood during a quit attempt supported by contingency management (CM), in which abstinence from smoking was reinforced with money. Methods Thirty-six non-treatment seeking smokers participated in two fMRI sessions, one following 24-hr abstinence and one following smoking as usual. During each scan, participants completed a rewarded guessing task designed to elicit striatal activation in which they could earn smoking and monetary rewards delivered after the scan. Participants then engaged in a 3-week CM-supported quit attempt. Results As previously reported, 24-hr abstinence was associated with increased striatal activation in anticipation of smoking reward and decreased activation in anticipation of monetary reward. Individuals exhibiting greater decrements in right striatal activation to monetary reward during abstinence (controlling for activation during non-abstinence) were more likely to lapse during CM (p<.05), even when controlling for other predictors of lapse outcome (e.g., craving); no association was seen for smoking reward. Conclusions These results are consistent with a growing number of studies indicating the specific importance of disrupted striatal processing of non-drug reward in nicotine dependence, and highlight the importance of individual differences in abstinence-induced deficits in striatal function for smoking cessation. PMID:26660448

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

    PubMed

    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

    NASA Astrophysics Data System (ADS)

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

    PubMed Central

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

    2016-01-01

    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. PMID:27078207

  1. Characterization of groundwater and surface water mixing in a semiconfined karst aquifer using time-lapse electrical resistivity tomography

    NASA Astrophysics Data System (ADS)

    Meyerhoff, Steven B.; Maxwell, Reed M.; Revil, André; Martin, Jonathan B.; Karaoulis, Marios; Graham, Wendy D.

    2014-03-01

    Groundwater flow in karst includes exchange of water between large fractures, conduits, and the surrounding porous matrix, which impacts both water quality and quantity. Electrical resistivity tomography combined with end-member mixing analysis (EMMA) and numerical flow and transport modeling was used to study mixing of karst conduit and matrix waters to understand spatial and temporal patterns of mixing during high flow and base flow conditions. To our knowledge, this is the first time EMMA and synthetic geophysical simulations have been combined. Here we interpret an 8 week time-lapse electrical resistivity data set to assess groundwater-surface mixing. We simulate flow between the karst conduits and the porous matrix to determine fractions of water recharged to conduits that has mixed with groundwater stored in the pore space of the matrix using a flow and transport model in a synthetic time-lapse resistivity inversion. Comparing the field and synthetic inversions, our results enable us to estimate exchange dynamics, spatial mixing, and flow conditions. Results showed that mixing occurred at a volumetric flux of 56 m3/d with a dispersivity around 1.69 m during the geophysical experiment. For these conditions, it was determined that conduit water composition ranged from 75% groundwater during base flow conditions to less than 50% groundwater in high flow conditions. Though subject to some uncertainties, the time-lapse inversion process provides a means to predict changing hydrologic conditions, leading to mixing of surface water and ground water and thus changes to water quantity and quality, as well as potential for water-rock reactions, in a semiconfined, sink-rise system.

  2. Blunted striatal response to monetary reward anticipation during smoking abstinence predicts lapse during a contingency-managed quit attempt.

    PubMed

    Sweitzer, Maggie M; Geier, Charles F; Denlinger, Rachel; Forbes, Erika E; Raiff, Bethany R; Dallery, Jesse; McClernon, F J; Donny, Eric C

    2016-03-01

    Tobacco smoking is associated with dysregulated reward processing within the striatum, characterized by hypersensitivity to smoking rewards and hyposensitivity to non-smoking rewards. This bias toward smoking reward at the expense of alternative rewards is further exacerbated by deprivation from smoking, which may contribute to difficulty maintaining abstinence during a quit attempt. We examined whether abstinence-induced changes in striatal processing of rewards predicted lapse likelihood during a quit attempt supported by contingency management (CM), in which abstinence from smoking was reinforced with money. Thirty-six non-treatment-seeking smokers participated in two functional MRI (fMRI) sessions, one following 24-h abstinence and one following smoking as usual. During each scan, participants completed a rewarded guessing task designed to elicit striatal activation in which they could earn smoking and monetary rewards delivered after the scan. Participants then engaged in a 3-week CM-supported quit attempt. As previously reported, 24-h abstinence was associated with increased striatal activation in anticipation of smoking reward and decreased activation in anticipation of monetary reward. Individuals exhibiting greater decrements in right striatal activation to monetary reward during abstinence (controlling for activation during non-abstinence) were more likely to lapse during CM (p < 0.025), even when controlling for other predictors of lapse outcome (e.g., craving); no association was seen for smoking reward. These results are consistent with a growing number of studies indicating the specific importance of disrupted striatal processing of non-drug reward in nicotine dependence and highlight the importance of individual differences in abstinence-induced deficits in striatal function for smoking cessation.

  3. Estimating rheological properties of lava flows using high-resolution time lapse imaging

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

    During effusive eruptions, property and infrastructure can be threatened by lava flow inundation. In order to maximise the effectiveness of the response to such an event, it is necessary to be able to reliably forecast the area that will be affected. One of the major controls on the advance of a lava flow is its rheology, which is spatially and temporally variable, and depends on many underlying factors. Estimating the rheological properties of a lava flow, and the change in these over space and time is therefore of the utmost importance. Here we report estimates of rheological properties made from geometric and velocity measurements on integrated topographic and image data using the method of Ellis et al. (2004) (Ellis B, Wilson L & Pinkerton H (2004) Estimating the rheology of basaltic lava flows. Lunar & Planetary Science XXXV Abst. 1550). These are then compared to the viscosity predicted from composition and temperature by the GRD model (Giordano D, Russell JK, & Dingwell DB (2008) Viscosity of Magmatic Liquids: A Model. Earth & Planetary Science Letters, 271, 123-134). During the 13 May 2008 - 6 July 2009 eruption of Mt Etna, Sicily, lava flows were emplaced into the Valle del Bove, reaching a maximum length of >6 km. Towards the end of the eruption, multiple channelized aa flows were active simultaneously, reaching tens to hundreds of metres in length. Flow lifetimes were of the order hours to days. In the last month of the eruption, we installed a Canon EOS 450D camera at Pizzi Deneri, on the north side of the Valle del Bove, to collect visible images at 15-minute intervals. On one day, topographic data (using a Riegl LPM-321 terrestrial laser scanner) and thermal images (using a FLIR Thermacam S40) were also collected from this location. The fronts of some of the larger flows were tracked through the time lapse image sequence. Using knowledge of the camera imaging geometry, the pixel tracks were reprojected onto the topographic surface to determine flow

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

    NASA Astrophysics Data System (ADS)

    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

  5. Developmental pathway of somatic embryogenesis in Picea abies as revealed by time-lapse tracking.

    PubMed

    Filonova, L H; Bozhkov, P V; von Arnold, S

    2000-02-01

    Several coniferous species can be propagated via somatic embryogenesis. This is a useful method for clonal propagation, but it can also be used for studying how embryo development is regulated in conifers. However, in conifers it is not known to what extent somatic and zygotic embryos develop similarly, because there has been little research on the origin and development of somatic embryos. A time-lapse tracking technique has been set up, and the development of more than 2000 single cells and few-celled aggregates isolated from embryogenic suspension cultures of Norway spruce (Picea abies L. Karst.) and embedded in thin layers of agarose has been traced. Experiments have shown that somatic embryos develop from proembryogenic masses which pass through a series of three characteristic stages distinguished by cellular organization and cell number (stages I, II and III) to transdifferentiate to somatic embryos. Microscopic inspection of different types of structures has revealed that proembryogenic masses are characterized by high interclonal variation of shape and cellular constitution. In contrast, somatic embryos are morphologically conservative structures, possessing a distinct protoderm-like cell layer as well as embryonal tube cells and suspensor. The lack of staining of the arabinogalactan protein epitope recognized by the monoclonal antibody JIM13 was shown to be an efficient marker for distinguishing proembryogenic masses from somatic embryos. The vast majority of cells in proembryogenic masses expressed this epitope and none of cells in the early somatic embryos. The conditions that promote cell proliferation (i.e. the presence of exogenous auxin and cytokinin), inhibit somatic embryo formation; instead, continuous multiplication of stage I proembryogenic masses by unequal division of embryogenic cells with dense cytoplasm is the prevailing process. Once somatic embryos have formed, their further development to mature forms requires abscisic acid and shares a

  6. Time-lapse 3D electrical resistivity tomography to monitor soil-plant interactions

    NASA Astrophysics Data System (ADS)

    Boaga, Jacopo; Rossi, Matteo; Cassiani, Giorgio; Putti, Mario

    2013-04-01

    In this work we present the application of time-lapse non-invasive 3D micro- electrical tomography (ERT) to monitor soil-plant interactions in the root zone in the framework of the FP7 Project CLIMB (Climate Induced Changes on the Hydrology of Mediterranean Basins). The goal of the study is to gain a better understanding of the soil-vegetation interactions by the use of non-invasive techniques. We designed, built and installed a 3D electrical tomography apparatus for the monitoring of the root zone of a single apple tree in an orchard located in the Trentino region, Northern Italy. The micro-ERT apparatus consists of 48 buried electrodes on 4 instrumented micro boreholes plus 24 mini-electrodes on the surface spaced 0.1 m on a square grid. We collected repeated ERT and TDR soil moisture measurements for one year and performed two different controlled irrigation tests: one during a very dry Summer and one during a very wet and highly dynamic plant growing Spring period. We also ran laboratory analyses on soil specimens, in order to evaluate the electrical response at different saturation steps. The results demonstrate that 3D micro-ERT is capable of characterizing subsoil conditions and monitoring root zone activities, especially in terms of root zone suction regions. In particular, we note that in very dry conditions, 3D micro ERT can image water plumes in the shallow subsoil produced by a drip irrigation system. In the very dynamic growing season, under abundant irrigation, micro 3D ERT can detect the main suction zones caused by the tree root activity. Even though the quantitative use of this technique for moisture content balance suffers from well-known inversion difficulties, even the pure imaging of the active root zone is a valuable contribution. However the integration of the measurements in a fully coupled hydrogeophysical inversion is the way forward for a better understanding of subsoil interactions between biomass, hydrosphere and atmosphere.

  7. Time-lapse Geophysical Monitoring of the Subsurface Hydrology at Kings Park, Western Australia

    NASA Astrophysics Data System (ADS)

    Adekoya, Tunde; McGrath, Gavan; Leopold, Matthias; Shragge, Jeffrey; Challis, Anthea; Stevens, Jason; Miller, Ben

    2015-04-01

    The increasing occurrence of drought stress throughout Southwestern Western Australia is postulated to have contributed to the decline of Banksia populations both in Kings Park, Perth, and in the Banksia woodlands in the greater Swan Coastal Plain region. To help quantify these assertions, there is an urgent need to better understand the base levels of soil moisture content - as well as seasonal variations thereof - in these geographical regions. We conducted time-lapse (TL) electrical resistivity tomography (ERT) and ground penetrating radar (GPR) methods on a monthly basis (May-August 2014). In addition, at each site we hand-augured test holes to a depth of 3-4 m and collected samples at 20-cm intervals to enable grain-size analysis, soil moisture content and water retention tests. PR2 capacitance probe measurements were also acquired when augering to enable a moisture content comparison study. The acquired TL ERT datasets were inverted using 2D EarthImager software and the temporal variations in resistivity were interpreted in terms of changes in moisture content. The TL ERT data reveal significant calendar variations in the spatial distribution of moisture content. The TL ERT inversions also detected isolated less resistive lithologies and the depth to groundwater. Processed TL GPR data were interpreted to show vertical variations in the vadose zone moisture content. The water content variations were consistent with the rainfall data. The grain-size distributions of the samples were analysed statistically. The apparent resistivity values from the analysed samples and observed volumetric water content are strongly correlated (R2=0.84) as may be expected from Archie's law. Soil moisture content analysis results including the PR2 probe measurements were plotted as a function of depth, the result shows vertical variations in moisture content with depth. The hydrological tests indicated the properties of the subsurface lithologies and confirm the responses of the

  8. A direct algorithm for convective adjustment of the vertical temperature profile for an arbitrary critical lapse rate

    NASA Technical Reports Server (NTRS)

    Akmaev, Rashid A.

    1991-01-01

    An efficient direct algorithm of convective adjustment for an arbitrary critical value of the vertical temperature lapse rate gamma is proposed. The algorithm provides an exact and unique solution of a standard convective adjustment problem for models with temperature specified either on nonuniformly spaced levels or for layers of different thicknesses in pressure, sigma, or other vertical coordinate related to pressure. The algorithm may be recommended for use either directly in atmospheric models not explicitly including a hydrologic cycle with prescribed gamma, or as a part of more complicated parameterizations of moist convection, where gamma may be calculated depending on relative humidity.

  9. Preliminary observations on polar body extrusion and pronuclear formation in human oocytes using time-lapse video cinematography.

    PubMed

    Payne, D; Flaherty, S P; Barry, M F; Matthews, C D

    1997-03-01

    In this study, we have used time-lapse video cinematography to study fertilization in 50 human oocytes that had undergone intracytoplasmic sperm injection (ICSI). Time-lapse recording commenced shortly after ICSI and proceeded for 17-20 h. Oocytes were cultured in an environmental chamber which was maintained under standard culture conditions. Overall, 38 oocytes (76%) were fertilized normally, and the fertilization rate and embryo quality were not significantly different from 487 sibling oocytes cultured in a conventional incubator. Normal fertilization followed a defined course of events, although the timing of these events varied markedly between oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular waves of granulation within the ooplasm which had a periodicity of 20-53 min. The sperm head decondensed during this granulation phase. The second polar body was then extruded, and this was followed by the central formation of the male pronucleus. The female pronucleus formed in the cytoplasm adjacent to the second polar body at the same time as, or slightly after, the male pronucleus, and was subsequently drawn towards the male pronucleus until the two abutted. Both pronuclei then increased in size, the nucleoli moved around within the pronuclei and some nucleoli coalesced. During pronuclear growth, the organelles contracted from the cortex towards the centre of the oocyte, leaving a clear cortical zone. The oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during the course of the observation period. The female pronucleus was significantly smaller in diameter than the male pronucleus (24.1 and 22.4 microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0 respectively, P < 0.0001). After time-lapse recording, oocytes were cultured for 48 h prior to embryo transfer or cryopreservation. Embryo quality was related to fertilization events and periodicity of the cytoplasmic wave, and it was found that good quality embryos

  10. A direct algorithm for convective adjustment of the vertical temperature profile for an arbitrary critical lapse rate

    NASA Technical Reports Server (NTRS)

    Akmaev, Rashid A.

    1991-01-01

    An efficient direct algorithm of convective adjustment for an arbitrary critical value of the vertical temperature lapse rate gamma is proposed. The algorithm provides an exact and unique solution of a standard convective adjustment problem for models with temperature specified either on nonuniformly spaced levels or for layers of different thicknesses in pressure, sigma, or other vertical coordinate related to pressure. The algorithm may be recommended for use either directly in atmospheric models not explicitly including a hydrologic cycle with prescribed gamma, or as a part of more complicated parameterizations of moist convection, where gamma may be calculated depending on relative humidity.

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

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed Central

    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. PMID:28002463

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

    PubMed

    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.

  15. Time-lapse walkaway VSP imaging using reverse-time migration in the angle domain for monitoring CO2 injection at the SACROC EOR field

    NASA Astrophysics Data System (ADS)

    Huang, L.; Huang, H.

    2012-12-01

    Time-lapse walkaway vertical seismic profiling (VSP) surveys can reveal important reservoir changes caused by CO2 injection. We study the capability of time-lapse walkaway VSP imaging using reverse-time migration in the angle-domain for monitoring CO2 injection. During the Phase II project of the Southwest Regional Partnership on Carbon Sequestration, one baseline and one repeat walkaway VSP surveys were conducted in 2008 and 2009, respectively, at the SACROC enhanced oil recovery (EOR) field for monitoring CO2 injection. The datasets were acquired by Baker Atlas in collaboration with Kinder Morgan. In this study, we apply reverse-time migration in the angle domain to the time-lapse walkaway VSP datasets from the SACROC EOR field, and conduct detailed analyses of common-image gathers. Our migration results demonstrate that reverse-time migration in the angle domain produces images of time-lapse walkaway VSP data with a better image quality compared to those obtained using conventional reverse-time migration. The time-lapse image difference along the bottom of the reservoir where CO2 is injected is much more significant than that along the top of the reservoir. This is partially because we use the same baseline velocity model for migrations of both datasets. The reservoir velocity decreases during CO2 injection, leading to slightly change in the migration image location along the bottom of the reservoir for the repeat VSP data.

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

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  18. Viral Plaque Analysis on a Wide Field-of-view, Time-lapse, On-chip Imaging Platform

    PubMed Central

    Han, Chao; Yang, Changhuei

    2014-01-01

    The observation of viral plaques is the standard method for determining viral titer and understanding the behaviors of viruses. Here, we report the application of a wide field-of-view (FOV), time-lapse, on-chip imaging platform, termed the ePetri, for plaque analysis of murine norovirus 1 (MNV-1). The ePetri offers the ability to dynamically track plaques at the individual cell death event level over a wide FOV of 6 mm × 4 mm. As demonstration, we captured high-resolution time-lapse images of MNV-1-infected cells at 30 min intervals. We implemented a customized image-processing program containing a density-based clustering algorithm to analyze the spatial-temporal distribution of cell death events to identify plaques at their earliest stages. By using the results in a viral titer count format, we showed that our approach gives results that are comparable to conventional plaque assays. We further showed that the extra information collected by the ePetri can be used to monitor the dynamics of plaque formation and growth. Finally, we performed a demonstration experiment to show the relevance of such an experimental format for viral inhibitor study. We believe the ePetri is a simple and compact solution for the automation of viral plaque assays, plaque behavior analysis, and antiviral drug discovery and study. PMID:24611157

  19. On the possibility of time-lapse ultrahigh-resolution optical coherence tomography for bladder cancer grading

    NASA Astrophysics Data System (ADS)

    Yuan, Zhijia; Chen, Bai; Ren, Hugang; Pan, Yingtian

    2009-09-01

    It has been recently demonstrated that the cellular details of bladder epithelium embedded in speckle noise can be uncovered with time-lapse ultrahigh-resolution optical coherence tomography (TL-uOCT) by proper time-lapse frame averaging that takes advantage of cellular micromotion in fresh biological tissue ex vivo. Here, spectral-domain 3-D TL-uOCT is reported to further improve the image fidelity, and new experimental evidence is presented to differentiate normal and cancerous nuclei of rodent bladder epithelia. Results of animal cancer study reveal that despite a slight overestimation (e.g., <10%) of nuclear size (DN) to histological evaluation, TL-uOCT is capable of distinguishing normal (DN~7 μm) and cancerous (e.g., high-grade DN''~13 μm) urothelia, which may potentially be very useful for enhancing the diagnosis of nonpapillary bladder cancer. More animal study is being conducted to examine the utility to differentiate hyperplasia, dysplasia, and carcinoma in situ.

  20. Viral plaque analysis on a wide field-of-view, time-lapse, on-chip imaging platform.

    PubMed

    Han, Chao; Yang, Changhuei

    2014-08-07

    The observation of viral plaques is the standard method for determining the viral titer and understanding the behaviors of viruses. Here, we report the application of a wide field-of-view (FOV), time-lapse, on-chip imaging platform, termed the ePetri, for plaque analysis of murine norovirus 1 (MNV-1). The ePetri offers the ability to dynamically track plaques at the individual cell death event level over a wide FOV of 6 mm × 4 mm. As demonstration, we captured high-resolution time-lapse images of MNV-1-infected cells at 30 min intervals. We implemented a customized image-processing program containing a density-based clustering algorithm to analyze the spatial-temporal distribution of cell death events to identify plaques at their earliest stages. By using the results in a viral titer count format, we showed that our approach gives results that are comparable to conventional plaque assays. We further showed that the extra information collected by the ePetri can be used to monitor the dynamics of plaque formation and growth. Finally, we performed a demonstration experiment to show the relevance of such an experimental format for viral inhibitor study. We believe the ePetri is a simple and compact solution for the automation of viral plaque assays, plaque behavior analysis, and antiviral drug discovery and study.

  1. Visualization of craniofacial development in the sox10: kaede transgenic zebrafish line using time-lapse confocal microscopy.

    PubMed

    Gfrerer, Lisa; Dougherty, Max; Liao, Eric C

    2013-09-30

    Vertebrate palatogenesis is a highly choreographed and complex developmental process, which involves migration of cranial neural crest (CNC) cells, convergence and extension of facial prominences, and maturation of the craniofacial skeleton. To study the contribution of the cranial neural crest to specific regions of the zebrafish palate a sox10: kaede transgenic zebrafish line was generated. Sox10 provides lineage restriction of the kaede reporter protein to the neural crest, thereby making the cell labeling a more precise process than traditional dye or reporter mRNA injection. Kaede is a photo-convertible protein that turns from green to red after photo activation and makes it possible to follow cells precisely. The sox10: kaede transgenic line was used to perform lineage analysis to delineate CNC cell populations that give rise to maxillary versus mandibular elements and illustrate homology of facial prominences to amniotes. This protocol describes the steps to generate a live time-lapse video of a sox10: kaede zebrafish embryo. Development of the ethmoid plate will serve as a practical example. This protocol can be applied to making a time-lapse confocal recording of any kaede or similar photoconvertible reporter protein in transgenic zebrafish. Furthermore, it can be used to capture not only normal, but also abnormal development of craniofacial structures in the zebrafish mutants.

  2. High-resolution Time-lapse Imaging and Automated Analysis of Microtubule Dynamics in Living Human Umbilical Vein Endothelial Cells

    PubMed Central

    Braun, Alexander; Caesar, Nicole M.; Dang, Kyvan; Myers, Kenneth A.

    2016-01-01

    The physiological process by which new vasculature forms from existing vasculature requires specific signaling events that trigger morphological changes within individual endothelial cells (ECs). These processes are critical for homeostatic maintenance such as wound healing, and are also crucial in promoting tumor growth and metastasis. EC morphology is defined by the organization of the cytoskeleton, a tightly regulated system of actin and microtubule (MT) dynamics that is known to control EC branching, polarity and directional migration, essential components of angiogenesis. To study MT dynamics, we used high-resolution fluorescence microscopy coupled with computational image analysis of fluorescently-labeled MT plus-ends to investigate MT growth dynamics and the regulation of EC branching morphology and directional migration. Time-lapse imaging of living Human Umbilical Vein Endothelial Cells (HUVECs) was performed following transfection with fluorescently-labeled MT End Binding protein 3 (EB3) and Mitotic Centromere Associated Kinesin (MCAK)-specific cDNA constructs to evaluate effects on MT dynamics. PlusTipTracker software was used to track EB3-labeled MT plus ends in order to measure MT growth speeds and MT growth lifetimes in time-lapse images. This methodology allows for the study of MT dynamics and the identification of how localized regulation of MT dynamics within sub-cellular regions contributes to the angiogenic processes of EC branching and migration. PMID:27584860

  3. Estimation of temporal variations in path-averaged atmospheric refractive index gradient from time-lapse imagery

    NASA Astrophysics Data System (ADS)

    Basu, Santasri; McCrae, Jack E.; Fiorino, Steven; Przelomski, Jared

    2016-09-01

    The sea level vertical refractive index gradient in the U.S. Standard Atmosphere model is -2.7×10-8 m-1 at 500 nm. At any particular location, the actual refractive index gradient varies due to turbulence and local weather conditions. An imaging experiment was conducted to measure the temporal variability of this gradient. A tripod mounted digital camera captured images of a distant building every minute. Atmospheric turbulence caused the images to wander quickly, randomly, and statistically isotropically and changes in the average refractive index gradient along the path caused the images to move vertically and more slowly. The temporal variations of the refractive index gradient were estimated from the slow, vertical motion of the building over a period of several days. Comparisons with observational data showed the gradient variations derived from the time-lapse imagery correlated well with solar heating and other weather conditions. The time-lapse imaging approach has the potential to be used as a validation tool for numerical weather models. These validations will benefit directed energy simulation tools and applications.

  4. Localized time-lapse elastic waveform inversion using wave-equation redatuming method: 2D parametric studies

    NASA Astrophysics Data System (ADS)

    Yuan, S.; Fuji, N.; Singh, S. C.; Borisov, D.

    2016-12-01

    We present a novel methodology to invert seismic data locally through the combination of wavefield injection and extrapolation method. Seismic full waveform inversion has proved its promising resolving power in seismology community for these decades. However, the computational cost for 3D practical scale elastic or viscoelastic waveform inversion remains still challenging. The computational cost is much more severe for time-lapse surveys, which requires real-time model estimation on a daily or weekly basis. Besides, changes of the structures during time-lapse surveys are likely to occur within a smaller area, such as oil and gas reservoir or CO2 injection wells. We propose methods that effectively and quantitatively image the localized structure change relatively far from source and receiver arrays. We thus have to perform both forward modeling and waveform inversions inside the region that contain neither source nor receiver. Firstly, we look for the equivalent source expression inside the region of interest by wavefield injection method. Secondly, we extrapolate wavefield from physical receivers to an array of virtual receivers by using correlation-type representation theorem. In this paper, we present elastic 2D numerical examples of our methods and quantitatively evaluate errors of obtained models, in comparison with those from full-model inversions. The results show that the proposed localized waveform inversion is more efficient, accurate and robust even under existence of errors in both initial models and data.

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

    NASA Astrophysics Data System (ADS)

    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).

  6. A laboratory validation study of the time-lapse oscillatory pumping test for leakage detection in geological repositories

    NASA Astrophysics Data System (ADS)

    Sun, Alexander Y.; Lu, Jiemin; Islam, Akand

    2017-05-01

    Geologic repositories are extensively used for disposing byproducts in mineral and energy industries. The safety and reliability of these repositories are a primary concern to environmental regulators and the public. Time-lapse oscillatory pumping test (OPT) has been introduced recently as a pressure-based technique for detecting potential leakage in geologic repositories. By routinely conducting OPT at a number of pulsing frequencies, an operator may identify the potential repository anomalies in the frequency domain, alleviating the ambiguity caused by reservoir noise and improving the signal-to-noise ratio. Building on previous theoretical and field studies, this work performed a series of laboratory experiments to validate the concept of time-lapse OPT using a custom made, stainless steel tank under relatively high pressures. The experimental configuration simulates a miniature geologic storage repository consisting of three layers (i.e., injection zone, caprock, and above-zone aquifer). Results show that leakage in the injection zone led to deviations in the power spectrum of observed pressure data, and the amplitude of which also increases with decreasing pulsing frequencies. The experimental results are further analyzed by developing a 3D flow model, using which the model parameters are estimated through frequency domain inversion.

  7. Assessment of ice-dam collapse by time-lapse photos at the Perito Moreno glacier, Argentina

    NASA Astrophysics Data System (ADS)

    Lenzano, M. G.; Lannutti, E.; Toth, C. K.; Lenzano, L. E.; Lovecchio, A.

    2014-11-01

    This research provides a feasibility study on the implementation and performance assessment of time-lapse processing of a monoscopic image sequence, acquired by a calibrated camera in the Perito Moreno Glacier in Argentina. The glacier is located at 50°28'23" S, 73°02'10" W at the Parque Nacional Los Glaciares, South Patagonia Icefield, Santa Cruz and has experienced minor fluctuations and unusual behavior since the early 1960's to present. The objective of this study was to determine the evolution and changes in the ice-dam of the Perito Moreno glacier that started on November, 23 2012 and collapsed on January 19, 2013. Two images every 24 hours were acquired since October 2012 until February 2013, a total of 135 days. Image information was supported by ground data. Image and ground data was correlated with a 2D affine transformation. This technique allows the determination of the distortions in the images and estimating the values of scale factors. This, along with an accurate time-lapse interval, has produced accurate data for the analysis. In addition, changes in the level of the Brazo Rico lake were validated with direct data in order to determine the degree of uncertainty in the estimation of changes in the glacier. Based on the calculations, advance rates of the front of the Perito Moreno glacier were estimated at 0.67 m/d ± 0.003 m, and the tunnel evolution was also recorded.

  8. 3D time-lapse seismic traveltime tomography for detecting near surface velocity variations: a case study from the Ketzin CO2 storage pilot site

    NASA Astrophysics Data System (ADS)

    Zhang, Fengjiao; Juhlin, Christopher; Huang, Fei; Lüth, Stefan

    2016-04-01

    Time-lapse seismic methods are an important tool for monitoring CO2 migration and storage in geological formations. Near surface variations are one of the major problems which may introduce time-lapse noise in the application of land based seismic monitoring. Conventional reflection seismic methods have difficulties in imaging near surface structures (10-30 m depth) due to the limitation of the methods themselves. Traveltime tomography is a commonly used method to reconstruct the subsurface velocity model. It can often provide extra information on near surface structures which is difficult to obtain by the conventional reflection seismic method. In this study, we apply traveltime tomography to 3D time-lapse seismic data sets acquired from at the Ketzin CO2 storage site. We also test different inversion strategies for traveltime tomography to investigate which one is more suitable for this case study. The results show good correlation with near surface variations obtained by other studies.

  9. Time-lapse full waveform inversion of vertical seismic profile data: Workflow and application to the CO2CRC Otway project

    NASA Astrophysics Data System (ADS)

    Egorov, Anton; Pevzner, Roman; Bóna, Andrej; Glubokovskikh, Stanislav; Puzyrev, Vladimir; Tertyshnikov, Konstantin; Gurevich, Boris

    2017-07-01

    Vertical seismic profile (VSP) is one of the technologies for monitoring hydrocarbon production and CO2 geosequestration. However, quantitative interpretation of time-lapse VSP is challenging due to its irregular distribution of source-receiver offsets. One way to overcome this challenge is to use full waveform inversion (FWI), which does not require regular offsets. We present a workflow of elastic FWI applied to offset vertical seismic profile data for the purpose of identification and estimation of time-lapse changes introduced by injection of 15,000 t of CO2-rich gas mixture at 1.5 km depth. Application of this workflow to both synthetic and field data shows that elastic FWI is able to detect and quantify the time-lapse anomaly in P wave velocity with the magnitude of 100-150 m/s.

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

    NASA Astrophysics Data System (ADS)

    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

  11. Understanding infiltration and groundwater flow at an artificial recharge facility using time-lapse gravity data

    NASA Astrophysics Data System (ADS)

    Kennedy, Jeffrey

    Groundwater provides a fundamental resource for modern life. Throughout the world, groundwater is managed by storing (recharging) it underground in natural aquifers for future withdrawal and consumptive use. In Arizona, over 4 million people benefit from managed aquifer storage, but little effort is made to track the movement of recharged water through the subsurface. Motivated by current limitations in our ability to monitor percolation and groundwater movement at the scale of a recharge facility, an effort to collect time-lapse gravity data was carried out at the Southern Avra Valley Storage and Recovery Project (SAVSARP) operated by the City of Tucson, Arizona. In addition to collecting water-level data 12 wells, there were three primary gravity experiments: (1) five continuously-recording gravity meters (2 iGrav superconducting gravity meters and 3 gPhone gravity meters) were installed semi-permanently in control buildings adjacent to the recharge basins, (2) absolute gravity measurements were made at nine locations over a 17 month period, and (3) three relative-gravity campaigns were carried out on a network of 70 stations. This large-scale controlled experiment, with known infiltration and pumping rates, resulted in one of the most comprehensive datasets of its kind. Gravity data led to several hydrologic insights, both through direct measurement and modeling. First, the infiltration rate could be estimated accurately based on the initial rate of gravity change during infiltration, regardless of the specific yield. Using two gravity meters, the depth, and therefore speed, of the wetting front beneath a recharge basin was observed, including the time at which the water table was reached. Spatial maps of gravity change from relative gravity surveys show areas where infiltration efficiency is highest, and where groundwater accumulates; storage accumulated preferentially to the west of the recharge basins, away from pumping wells. Such information would be

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

    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 temperature change signal is not only added to present-day conditions, but also subtracted from a scenario experiment. We use the regional climate model COSMO-CLM with a grid spacing of approximately 50 km (EURO-CORDEX EUR-44 setup) using transient simulations (1950-2100) with the RCP8.5 emissions scenario. We demonstrate that the aforementioned extensions provide an elegant way to separate the full climate change signal into contributions from large-scale thermodynamics (LST), lapse-rate (LR) and large-scale circulation (LSC). In our framework the LSC effect also includes effects due to changes in land-sea contrast and the spatial variations of the SST warming pattern. We find that the LST effect yields a large-scale warming across Europe without any 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

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

    SciTech Connect

    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

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

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

    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

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

    PubMed

    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 (<37 weeks): 10.7% (TLS) vs. 12.3% (SI); and very preterm births (<34 weeks): 2.9% (TLS) vs. 3.3% (SI). No statistical differences were found in neonatal 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 (<2,500 g): 12.8% (TLS) vs. 12.3% (SI); very low birth weight (<1,500 g): 2.0% (TLS) vs. 2.4% (SI); or height: 50.3 cm (95% CI 49.6-50.9 cm) (TLS) vs. 49.7 (95% CI 48.9-50.4 cm) (SI). No major malformations or perinatal mortality were found in either of the two groups. No detrimental effects were observed in 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

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

    SciTech Connect

    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

  18. Identifying unsaturated soil hydraulic parameters using integrated hydrogeophysical inversion approach on time-lapse ground-penetrating radar data

    NASA Astrophysics Data System (ADS)

    Jadoon, K. Z.; Weihermüller, L.; Scharnagl, B.; Kowalsky, M. B.; Bechtold, M.; Hubbard, S. S.; Vereecken, H.; Lambot, S.

    2012-04-01

    Recently, ground-penetrating radar (GPR) has proven to have a great potential for high resolution, non-invasive mapping of the soil hydrogeophysical properties at the scale of interest. Common GPR techniques are usually based on ray-based travel time or reflection analyses to retrieve soil dielectric permittivity, which is strongly correlated to soil water content. These methods suffer, however, from two major limitations. First, only a part of the information in the GPR signal is considered (e.g., propagation time). Second, the forward model describing the radar data is subject to relatively strong simplifications with respect to electromagnetic wave propagation phenomena. These limitations typically results in errors in the reconstructed water content images and, moreover, this does not permit to exploit all information contained in the radar data. We explored an alternative method by using full-waveform hydrogeophysical inversion of time-lapse, proximal GPR data to remotely estimate the unsaturated soil hydraulic properties. The radar system is based on international standard vector network analyzer technology and a full-waveform model is used to describe wave propagation in the antenna-air-soil system, including antenna-soil interactions. A hydrodynamic model is used to constrain the inverse electromagnetic problem in reconstructing continuous vertical water content profiles. In that case the estimated parameters reduce to the soil hydraulic properties, thereby strongly reducing the dimensionality of the inverse problem. In this study, we present an application of the proposed method to a data set collected in a field experiment. The GPR model involves a full-waveform frequency-domain solution of Maxwell's equations for wave propagation in three-dimensional multilayered media. The hydrodynamic model used in this work is based on a one-dimensional solution of Richards equation and the hydrological simulator HYDRUS 1-D was used with a single- and dual

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

    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 o