Science.gov

Sample records for fast event recorder

  1. 49 CFR 229.135 - Event recorders.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Event recorders. 229.135 Section 229.135... § 229.135 Event recorders. (a) Duty to equip and record. Except as provided in paragraphs (c) and (d) of this section, a train operated faster than 30 miles per hour shall have an in-service event...

  2. 49 CFR 229.135 - Event recorders.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Event recorders. 229.135 Section 229.135... § 229.135 Event recorders. (a) Duty to equip and record. Except as provided in paragraphs (c) and (d) of this section, a train operated faster than 30 miles per hour shall have an in-service event...

  3. 49 CFR 229.135 - Event recorders.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Event recorders. 229.135 Section 229.135... § 229.135 Event recorders. (a) Duty to equip and record. Except as provided in paragraphs (c) and (d) of this section, a train operated faster than 30 miles per hour shall have an in-service event...

  4. 49 CFR 229.135 - Event recorders.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Event recorders. 229.135 Section 229.135... § 229.135 Event recorders. (a) Duty to equip and record. Except as provided in paragraphs (c) and (d) of this section, a train operated faster than 30 miles per hour shall have an in-service event...

  5. Subnoise detection of a fast random event.

    PubMed

    Ataie, V; Esman, D; Kuo, B P-P; Alic, N; Radic, S

    2015-12-11

    Observation of random, nonrepetitive phenomena is of critical importance in astronomy, spectroscopy, biology, and remote sensing. Heralded by weak signals, hidden in noise, they pose basic detection challenges. In contrast to repetitive waveforms, a single-instance signal cannot be separated from noise through averaging. Here, we show that a fast, randomly occurring event can be detected and extracted from a noisy background without conventional averaging. An isolated 80-picosecond pulse was received with confidence level exceeding 99%, even when accompanied by noise. Our detector relies on instantaneous spectral cloning and a single-step, coherent field processor. The ability to extract fast, subnoise events is expected to increase detection sensitivity in multiple disciplines. Additionally, the new spectral-cloning receiver can potentially intercept communication signals that are presently considered secure. Copyright © 2015, American Association for the Advancement of Science.

  6. 77 FR 48492 - Event Data Recorders

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-14

    ... National Highway Traffic Safety Administration 49 CFR Part 563 Event Data Recorders AGENCY: National... requirements related to event data recorders (EDRs) voluntarily installed on light vehicles. The petitioner... to standardize the data obtained through EDRs so that such data would provide information to...

  7. Event-recording devices with identification codes

    NASA Technical Reports Server (NTRS)

    Watters, David G. (Inventor); Huestis, David L. (Inventor); Bahr, Alfred J. (Inventor); Vidmar, Robert J. (Inventor)

    2003-01-01

    A recording device allows wireless interrogation to determine its identity and its state. The state indicates whether one or more physical or chemical events have taken place. In effect, the one or more physical or chemical events are recorded by the device. The identity of the device allows it to be distinguished from a number of similar devices. The recording device may be used in an array of devices that allows wireless probing by an interrogation unit. When probed, each device tells the interrogator who it is and what state it is in. The devices allow multiple use and the interrogator may use a logical reset to determine the state of each device. The interrogator can thus easily identify particular items in an array that have reached a particular condition. The device may record the status of each device in a database to maintain a history for each.

  8. 77 FR 59566 - Event Data Recorders

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-28

    ... National Highway Traffic Safety Administration 49 CFR Part 563 RIN 2127-AL14 Event Data Recorders..., 2012, make the following correction: Sec. 563.8 Data format On page 47557 in the table titled ``Table III--Reported Data Element Format'', in the ``Accuracy \\1\\'' column, in the twenty-fifth row, `` ms...

  9. Performance requirements for the laser event recorder

    NASA Astrophysics Data System (ADS)

    Tribble, Jerri; Sheehy, James B.; Schwarze, Craig R.; Vaillancourt, Robert; Carlson, Dave; Engel, James R.

    2005-05-01

    Lasers for defense applications continue to grow in power and fill in new portions of the spectrum, expanding the laser eye safety hazard, particularly to aircrew and aviation safety. The Laser Event Recorder Program within Naval Air Systems Command (NAVAIR) seeks to develop a low cost, self-contained laser sensor able to detect, warn and record laser exposures that hazard aircrew vision. The spectral and temporal range of hazardous lasers (400 to 1600 nm and pulsed to continuous) has presented a challenge in the past. However, diffractive optics and imaging technologies have enabled a solution to this growing threat. This paper will describe the technical requirements for the Laser Event Recorder, which are based on ANSI Z136.1 laser safety standards and common to its use on any platform. To support medical and operational laser eye protection, the LER extracts and records laser wavelength, radiant exposure, exposure duration, pulse structure, latitude, longitude, altitude and time of laser exposure. Specific performance and design issues of the LER prototype will be presented in a companion paper. In this paper, fundamental challenges to the requirements encountered during the first two years of research, development and successful outdoor testing will be reviewed. These include discrimination against all outdoor light levels and the impact of atmospheric beam propagation on accuracy of the radiant exposure determination. Required accuracy and response time of the determination of whether a laser exposure exceeds the maximum permissible exposure (MPE) will be described. Ongoing efforts to coordinate laser exposure reporting and medical management will also be discussed.

  10. A slow seismic event recorded in Pasadena

    SciTech Connect

    Kanamori, Hiroo )

    1989-12-01

    A prominent long-period wave with a duration of 2,000 sec or longer was recorded with a very-broadband system in Pasadena on June 18, 1988. This wave was not observed elsewhere, and is considered of local origin. The acceleration amplitude is 2.5 {times} 10{sup {minus}5} cm/sec{sup 2} in the northwest direction, with the vertical component less than 10% of the horizontal. The horizontal acceleration can be interpreted as due to a tilt of the ground of 2.5 {times} 10{sup {minus}8} radians to the radians to the northwest. A slowly propagating pressure wave with an amplitude of about 15 mbars could be the cause of the tilt; however, there were no reports suggesting such pressure changes. A more likely cause is a slow tectonic event near Pasadena. The required magnitude of such a slow event is M{sub w} = 0, 2, and 4, for a distance of 0.1, 1, and 10 km respectively. This event could be part of a tectonic episode associated with the larger earthquakes which occurred in southern California around this time, especially the December 3, 1988, Pasadena earthquake (M{sub L} = 4.9) which occurred six months later within 4 km of the Pasadena station.

  11. Biomarker Records Associated with Mass Extinction Events

    NASA Astrophysics Data System (ADS)

    Whiteside, Jessica H.; Grice, Kliti

    2016-06-01

    The history of life on Earth is punctuated by a series of mass extinction episodes that vary widely in their magnitude, duration, and cause. Biomarkers are a powerful tool for the reconstruction of historical environmental conditions and can therefore provide insights into the cause and responses to ancient extinction events. In examining the five largest mass extinctions in the geological record, investigators have used biomarkers to elucidate key processes such as eutrophy, euxinia, ocean acidification, changes in hydrological balance, and changes in atmospheric CO2. By using these molecular fossils to understand how Earth and its ecosystems have responded to unusual environmental activity during these extinctions, models can be made to predict how Earth will respond to future changes in its climate.

  12. Fast drift kilometric radio bursts and solar proton events

    NASA Technical Reports Server (NTRS)

    Cliver, E. W.; Kahler, S. W.; Cane, H. V.; Mcguire, R. E.; Vonrosenvinge, T. T.; Stone, R. G.

    1985-01-01

    Initial results of a comparative study of major fast drift kilometric bursts and solar proton events from Sep. 1978 to Feb. 1983 are presented. It was found that only about half of all intense, long duration ( 40 min above 500 sfu) 1 MHz bursts can be associated with F 20 MeV proton events. However, for the subset of such fast drift bursts accompanied by metric Type 2 and/or 4 activity (approximately 40% of the total), the degree of association with 20 MeV events is 80%. For the reverse association, it was found that proton events with J( 20 MeV) 0.01 1 pr cm(-2)s(-1)sr(-1)MeV(-1) were typically (approximately 80% of the time) preceded by intense 1 MHz bursts that exceeded the 500 sfu level for times 20 min (median duration approximately 35 min).

  13. Fast optical recording media based on semiconductor nanostructures for image recording and processing

    SciTech Connect

    Kasherininov, P. G. Tomasov, A. A.

    2008-11-15

    Fast optical recording media based on semiconductor nanostructures (CdTe, GaAs) for image recording and processing with a speed to 10{sup 6} cycle/s (which exceeds the speed of known recording media based on metal-insulator-semiconductor-(liquid crystal) (MIS-LC) structures by two to three orders of magnitude), a photosensitivity of 10{sup -2}V/cm{sup 2}, and a spatial resolution of 5-10 (line pairs)/mm are developed. Operating principles of nanostructures as fast optical recording media and methods for reading images recorded in such media are described. Fast optical processors for recording images in incoherent light based on CdTe crystal nanostructures are implemented. The possibility of their application to fabricate image correlators is shown.

  14. Text mining electronic health records to identify hospital adverse events.

    PubMed

    Gerdes, Lars Ulrik; Hardahl, Christian

    2013-01-01

    Manual reviews of health records to identify possible adverse events are time consuming. We are developing a method based on natural language processing to quickly search electronic health records for common triggers and adverse events. Our results agree fairly well with those obtained using manual reviews, and we therefore believe that it is possible to develop automatic tools for monitoring aspects of patient safety.

  15. Meteoritic event recorded in Antarctic ice

    SciTech Connect

    Harvey, R.P.; Dunbar, N.W.; McIntosh, W.C.; Esser, R.P.; Nishiizumi, Kuni; Taylor, S.; Caffee, M.W.

    1998-07-01

    During systematic sampling of volcanic ash (tephra) layers at a well-known Antarctic meteorite collection site (the Allan Hills main ice field), a band of unusually dark and rounded (many spheroidal) particles was discovered. This debris layer (BIT-58) extends parallel to the stratigraphy of the ice established from the tephra bands, apparently marking a single depositional event. The shapes, internal texture, major element composition, and levels of cosmogenic nuclides of particles from within BIT-58 all strongly suggest that this material represents ablation debris from the passage of a large H-group ordinary chondrite. Preliminary cosmogenic isotope dating suggests an age of 2.8 Ma, implying that the East Antarctic ice sheet has been stable since that time. The relationship of the Bit-58 layer to known impact events is not clear.

  16. Record events in growing populations: universality, correlation, and aging.

    PubMed

    Eliazar, Iddo; Klafter, Joseph

    2009-12-01

    This paper studies the occurrence of record events in score populations which grow stochastically in time. In Rényi's basic record model, a population of independent and identically distributed (i.i.d.) random scores grows deterministically--a single new score being added at each time step. Rényi's record theorem asserts that the resulting record events are independent, and that their occurrence probabilities decrease harmonically in time. Moreover, Rényi's result is universal--being independent of the distribution of the i.i.d. random scores. This paper considers an arbitrary stochastic growth of the score population--allowing the number of the i.i.d. random scores added at each time step to follow arbitrary stochastic dynamics. Exploring the stochastic growth model we: (i) establish a general analog of Rényi's record theorem; (ii) show that universality with respect to the distribution of the i.i.d. random scores is maintained; (iii) compute the distribution of the waiting times for record events; (iv) analyze the dependencies/independencies of the record events; and (v) analyze the aging/stationarity of the record events.

  17. Numerical simulations of fast transient events in the sun.

    NASA Astrophysics Data System (ADS)

    Casillas-Perez, G. A.; Jeyakumar, S.; Perez-Enriquez, R.

    2016-12-01

    Fast transients are dynamical phenomena that show up as high brightness temperature increments over a duration of less than a second. In the Sun these events have been observed in the radio band in various forms, such as radio spikes for example, often seen accompanying other phenomena like normal radio bursts and solar flares. The study of solar fast radio transients is important to understand the physical processes occurring in the solar corona and its possible relation to other solar phenomena where large amounts of energy are released. In this work, we report a code developed to study the evolution of an electron beam pulse injected into the solar corona. We show the tests to validate the code and some results that have been obtained from the numerical simulations that were carried out using this code.

  18. Late Eocene impact events recorded in deep-sea sediments

    NASA Technical Reports Server (NTRS)

    Glass, B. P.

    1988-01-01

    Raup and Sepkoski proposed that mass extinctions have occurred every 26 Myr during the last 250 Myr. In order to explain this 26 Myr periodicity, it was proposed that the mass extinctions were caused by periodic increases in cometary impacts. One method to test this hypothesis is to determine if there were periodic increases in impact events (based on crater ages) that correlate with mass extinctions. A way to test the hypothesis that mass extinctions were caused by periodic increases in impact cratering is to look for evidence of impact events in deep-sea deposits. This method allows direct observation of the temporal relationship between impact events and extinctions as recorded in the sedimentary record. There is evidence in the deep-sea record for two (possibly three) impact events in the late Eocene. The younger event, represented by the North American microtektite layer, is not associated with an Ir anomaly. The older event, defined by the cpx spherule layer, is associated with an Ir anomaly. However, neither of the two impact events recorded in late Eocene deposits appears to be associated with an unusual number of extinctions. Thus there is little evidence in the deep-sea record for an impact-related mass extinction in the late Eocene.

  19. Frog: The fast & realistic OpenGL event displayer

    NASA Astrophysics Data System (ADS)

    Quertenmont, Loïc

    2010-04-01

    FROG [1] [2] is a generic framework dedicated to visualisation of events in high energy physics experiment. It is suitable to any particular physics experiment or detector design. The code is light (< 3 MB) and fast (browsing time ~ 20 events per second for a large High Energy Physics experiment) and can run on various operating systems, as its object-oriented structure (C++) relies on the cross-platform OpenGL[3] and Glut [4] libraries. Moreover, Frog does not require installation of heavy third party libraries for the visualisation. This documents describes the features and principles of Frog version 1.106, its working scheme and numerous functionalities such as: 3D and 2D visualisation, graphical user interface, mouse interface, configuration files, production of pictures of various format, integration of personal objects, etc. Finally the application of FROG for physic experiment/environement, such as Gastof, CMS, ILD, Delphes will be presented for illustration.

  20. Functional fission of parvalbumin interneuron classes during fast network events

    PubMed Central

    Varga, Csaba; Oijala, Mikko; Lish, Jonathan; Szabo, Gergely G; Bezaire, Marianne; Marchionni, Ivan; Golshani, Peyman; Soltesz, Ivan

    2014-01-01

    Fast spiking, parvalbumin (PV) expressing hippocampal interneurons are classified into basket, axo-axonic (chandelier), and bistratified cells. These cell classes play key roles in regulating local circuit operations and rhythmogenesis by releasing GABA in precise temporal patterns onto distinct domains of principal cells. In this study, we show that each of the three major PV cell classes further splits into functionally distinct sub-classes during fast network events in vivo. During the slower (<10 Hz) theta oscillations, each cell class exhibited its own characteristic, relatively uniform firing behavior. However, during faster (>90 Hz) oscillations, within-class differences in PV interneuron discharges emerged, which segregated along specific features of dendritic structure or somatic location. Functional divergence of PV sub-classes during fast but not slow network oscillations effectively doubles the repertoire of spatio-temporal patterns of GABA release available for rapid circuit operations. DOI: http://dx.doi.org/10.7554/eLife.04006.001 PMID:25375253

  1. 10,000 yr record of extreme hydrologic events

    SciTech Connect

    Brown, S.L.; Bierman, P.R.; Lini, A.; Southon, J.

    2000-04-01

    Well-dated lacustrine sediments provide a hydrologic record indicating that the frequency and magnitude of runoff events, and by inference, storms, have varied over the past 10 k.y. in northern New England. The authors used five sediment cores and radiocarbon dating to develop a chronology of Holocene hydrologic events for the Ritterbush Pond basin, northern Vermont. Chemical and physical analyses allow them to identify 52 distinct layers of predominantly inorganic sediment that represent terrestrially derived material delivered to the pond by runoff events. The thickness of some layers suggests hydrologic events at least equal in size to, and probably much larger than, any storm or flood recorded during nearly 300 yr of written regional history. Layer thickness and frequency and, by analogy, storm size and recurrence, change through the Holocene. The largest events occurred 2620, 6840, and 9440 calibrated {sup 14}C years before present (cal {sup 14}C yr B.P.). The most frequent hydrologic events occurred in three periods: 1,750 to 2,620, 6,330 to 6,840, and > 8,600 cal yr B.P. The recurrence interval of layer deposition during stormy periods averages 130 {+-} 100 cal yr, whereas the recurrence interval during less stormy periods is longer, 270 {+-} 170 cal yr. The Ritterbush Pond event record illustrates the potential of inorganic lacustrine sediment to serve as a proxy record for estimating paleoflood frequency and deciphering climate change.

  2. Fast, Deep-Record-Length, Fiber-Coupled Photodiode Imaging Array for Plasma Diagnostics

    NASA Astrophysics Data System (ADS)

    Brockington, Samuel; Case, Andrew; Witherspoon, F. Douglas

    2014-10-01

    HyperV Technologies has been developing an imaging diagnostic comprised of an array of fast, low-cost, long-record-length, fiber-optically-coupled photodiode channels to investigate plasma dynamics and other fast, bright events. By coupling an imaging fiber bundle to a bank of amplified photodiode channels, imagers and streak imagers of 100 to 1000 pixels can be constructed. By interfacing analog photodiode systems directly to commercial analog-to-digital converters and modern memory chips, a prototype 100 pixel array with an extremely deep record length (128 k points at 20 Msamples/s) and 10 bit pixel resolution has already been achieved. HyperV now seeks to extend these techniques to construct a prototype 1000 Pixel framing camera with up to 100 Msamples/sec rate and 10 to 12 bit depth. Preliminary experimental results as well as Phase 2 plans will be discussed. Work supported by USDOE Phase 2 SBIR Grant DE-SC0009492.

  3. Fast, Deep-Record-Length, Fiber-Coupled Photodiode Imaging Array for Plasma Diagnostics

    NASA Astrophysics Data System (ADS)

    Brockington, Samuel; Case, Andrew; Witherspoon, F. Douglas

    2015-11-01

    HyperV Technologies has been developing an imaging diagnostic comprised of an array of fast, low-cost, long-record-length, fiber-optically-coupled photodiode channels to investigate plasma dynamics and other fast, bright events. By coupling an imaging fiber bundle to a bank of amplified photodiode channels, imagers and streak imagers can be constructed. By interfacing analog photodiode systems directly to commercial analog-to-digital converters and modern memory chips, a scalable solution for 100 to 1000 pixel systems with 14 bit resolution and record-lengths of 128k frames has been developed. HyperV is applying these techniques to construct a prototype 1000 Pixel framing camera with up to 100 Msamples/sec rate and 10 to 14 bit depth. Preliminary experimental results as well as future plans will be discussed. Work supported by USDOE Phase 2 SBIR Grant DE-SC0009492.

  4. Limb Event Brightenings and Fast Ejection Using IRIS Mission Observations

    NASA Astrophysics Data System (ADS)

    Tavabi, E.; Koutchmy, S.; Golub, L.

    2015-10-01

    The Interface Region Imaging Spectrograph (IRIS) of the recently commissioned NASA small explorer mission provides significantly more complete and higher resolution spectral coverage of the dynamical conditions inside the chromosphere and transition region (TR) than has been available ever before. High temporal, spatial (0.3'') and spectral resolution observations from the ultraviolet IRIS spectra near the solar limb reveal high-energy limb event brightenings (LEBs) at low chromospheric heights at about 1 Mm above the limb. They can be characterized as explosive events producing jets. We selected two events showing spectra of a confined eruption just off or near the quiet-Sun limb, the jet part showing obvious moving material with short-duration large Doppler shifts in three directions that were identified as macrospicules on slit-jaw (SJ) images in Si iv and He ii 304 Å. The events were analyzed from a sequence of very close rasters taken near the central meridian and the South Pole limb. We analyzed the processed SJ images and the simultaneously observed fast spectral sequences, which have large Doppler shifts, with a pair of redshifted elements together with a faster blueshifted element from almost the same position. Shifts correspond to velocities of up to 100 km s^{-1} in projection on the plane of the sky. Erupting spicules and macrospicules from these regions are visible in images taken before and after the spectra. The cool low first ionization potential (FIP) element simultaneous line emissions of the Mg ii h and k resonance lines do not clearly show a similar signature because of optical thickness effects, but the Si iv broadband SJ images do. The bidirectional plasma jets ejected from a small reconnection site are interpreted to be the result of coronal loop-loop interactions that lead to reconnection in nearby sites.

  5. Wireless event-recording device with identification codes

    NASA Technical Reports Server (NTRS)

    Watters, David G. (Inventor); Huestis, David L. (Inventor); Bahr, Alfred J. (Inventor)

    2004-01-01

    A wireless recording device can be interrogated to determine its identity and its state. The state indicates whether a particular physical or chemical event has taken place. In effect, the physical or chemical event is recorded by the device. The identity of the device allows it to be distinguished from a number of similar devices. Thus the sensor device may be used in an array of devices that can be probed by a wireless interrogation unit. The device tells the interrogator who it is and what state it is in. The interrogator can thus easily identify particular items in an array that have reached a particular condition.

  6. Ultra fast all-optical fiber pressure sensor for blast event evaluation

    NASA Astrophysics Data System (ADS)

    Wu, Nan; Wang, Wenhui; Tian, Ye; Niezrecki, Christopher; Wang, Xingwei

    2011-05-01

    Traumatic brain injury (TBI) is a great potential threat to soldiers who are exposed to explosions or athletes who receive cranial impacts. Protecting people from TBI has recently attracted a significant amount of attention due to recent military operations in the Middle East. Recording pressure transient data in a blast event is very critical to the understanding of the effects of blast events on TBI. However, due to the fast change of the pressure during blast events, very few sensors have the capability to effectively track the dynamic pressure transients. This paper reports an ultra fast, miniature and all-optical fiber pressure sensor which could be mounted at different locations of a helmet to measure the fast changing pressure simultaneously. The sensor is based on Fabry-Perot (FP) principle. The end face of the fiber is wet etched. A well controlled thickness silicon dioxide diaphragm is thermal bonded on the end face to form an FP cavity. A shock tube test was conducted at Natick Soldier Research Development and Engineering Center, where the sensors were mounted in a shock tube side by side with a reference sensor to measure the rapidly changing pressure. The results of the test demonstrated that the sensor developed had an improved rise time (shorter than 0.4 μs) when compared to a commercially available reference sensor.

  7. Automatic detection of fast oscillations (40–200 Hz) in scalp EEG recordings

    PubMed Central

    von Ellenrieder, Nicolás; Andrade-Valença, Luciana P.; Dubeau, François; Gotman, Jean

    2013-01-01

    Objective We aim to automatically detect fast oscillations (40–200 Hz) related to epilepsy on scalp EEG recordings. Methods The detector first finds localized increments of the signal power in narrow frequency bands. A simple classification based on two features, a narrowband to wideband signal amplitude ratio and an absolute narrowband signal amplitude, then allows for an important reduction in the number of false positives. Results When compared to an expert, the performance in 15 focal epilepsy patients resulted in 3.6 false positives per minute at 95% sensitivity, with at least 40% of the detected events being true positives. In most of the patients the channels showing the highest number of events according to the expert and the automatic detector were the same. Conclusions A high sensitivity is achieved with the proposed automatic detector, but results should be reviewed by an expert to remove false positives. Significance The time required to mark fast oscillations on scalp EEG recordings is drastically reduced with the use of the proposed detector. Thus, the automatic detector is a useful tool in studies aiming to create a better understanding of the fast oscillations visible on the scalp. PMID:21940200

  8. Event metadata records as a testbed for scalable data mining

    NASA Astrophysics Data System (ADS)

    van Gemmeren, P.; Malon, D.

    2010-04-01

    At a data rate of 200 hertz, event metadata records ("TAGs," in ATLAS parlance) provide fertile grounds for development and evaluation of tools for scalable data mining. It is easy, of course, to apply HEP-specific selection or classification rules to event records and to label such an exercise "data mining," but our interest is different. Advanced statistical methods and tools such as classification, association rule mining, and cluster analysis are common outside the high energy physics community. These tools can prove useful, not for discovery physics, but for learning about our data, our detector, and our software. A fixed and relatively simple schema makes TAG export to other storage technologies such as HDF5 straightforward. This simplifies the task of exploiting very-large-scale parallel platforms such as Argonne National Laboratory's BlueGene/P, currently the largest supercomputer in the world for open science, in the development of scalable tools for data mining. Using a domain-neutral scientific data format may also enable us to take advantage of existing data mining components from other communities. There is, further, a substantial literature on the topic of one-pass algorithms and stream mining techniques, and such tools may be inserted naturally at various points in the event data processing and distribution chain. This paper describes early experience with event metadata records from ATLAS simulation and commissioning as a testbed for scalable data mining tool development and evaluation.

  9. Extreme Drought Events Revealed in Amazon Tree Ring Records

    NASA Astrophysics Data System (ADS)

    Jenkins, H. S.; Baker, P. A.; Guilderson, T. P.

    2010-12-01

    The Amazon basin is a center of deep atmospheric convection and thus acts as a major engine for global hydrologic circulation. Yet despite its significance, a full understanding of Amazon rainfall variability remains elusive due to a poor historical record of climate. Temperate tree rings have been used extensively to reconstruct climate over the last thousand years, however less attention has been given to the application of dendrochronology in tropical regions, in large part due to a lower frequency of tree species known to produce annual rings. Here we present a tree ring record of drought extremes from the Madre de Dios region of southeastern Peru over the last 190 years. We confirm that tree ring growth in species Cedrela odorata is annual and show it to be well correlated with wet season precipitation. This correlation is used to identify extreme dry (and wet) events that have occurred in the past. We focus on drought events identified in the record as drought frequency is expected to increase over the Amazon in a warming climate. The Cedrela chronology records historic Amazon droughts of the 20th century previously identified in the literature and extends the record of drought for this region to the year 1816. Our analysis shows that there has been an increase in the frequency of extreme drought (mean recurrence interval = 5-6 years) since the turn of the 20th century and both Atlantic and Pacific sea surface temperature (SST) forcing mechanisms are implicated.

  10. Recording Adverse Events Following Joint Arthroplasty: Financial Implications and Validation of an Adverse Event Assessment Form.

    PubMed

    Lee, Matthew J; Mohamed, Khalid M S; Kelly, John C; Galbraith, John G; Street, John; Lenehan, Brian J

    2017-09-01

    In Ireland, funding of joint arthroplasty procedures has moved to a pay-by-results national tariff system. Typically, adverse clinical events are recorded via retrospective chart-abstraction methods by administrative staff. Missed or undocumented events not only affect the quality of patient care but also may unrealistically skew budgetary decisions that impact fiscal viability of the service. Accurate recording confers clinical benefits and financial transparency. The aim of this study was to compare a prospectively implemented adverse events form with the current national retrospective chart-abstraction method in terms of pay-by-results financial implications. An adverse events form adapted from a similar validated model was used to prospectively record complications in 51 patients undergoing total hip or knee arthroplasties. Results were compared with the same cohort using an existing data abstraction method. Both data sets were coded in accordance with current standards for case funding. Overall, 114 events were recorded during the study through prospective charting of adverse events, compared with 15 events documented by customary method (a significant discrepancy). Wound drainage (15.8%) was the most common complication, followed by anemia (7.9%), lower respiratory tract infections (7.9%), and cardiac events (7%). A total of €61,956 ($67,778) in missed funding was calculated as a result. This pilot study demonstrates the ability to improve capture of adverse events through use of a well-designed assessment form. Proper perioperative data handling is a critical aspect of financial subsidies, enabling optimal allocation of funds. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Observations of Early/Fast VLF Events on Vieques Island, Puerto Rico

    NASA Astrophysics Data System (ADS)

    Pasko, V. P.; Inan, U. S.; Wood, T. G.; Stanley, M. A.; Mathews, J. D.; George, J. J.; Fong, N. T.

    2002-12-01

    Early/Fast VLF events are registered as sudden (i.e., "fast" < 20 ms) subionospheric VLF signal changes, occurring simultaneously (i.e., "early", <20 ms) with lightning discharges [e.g., Inan et al., GRL, 20, 2355, 1993]. These events constitute evidence of the direct energetic coupling between tropospheric thunderstorms and the overlying mesospheric and lower ionospheric regions. In August-September 2001 Penn State University organized an experimental campaign in Puerto Rico to perform correlative studies of lightning and lightning-induced ionospheric effects. A set of instruments employed for these studies included Arecibo Observatory 430 MHz UHF radar, New Mexico Tech Interferometer, and a video system. As part of this campaign Stanford University deployed broadband and narrowband VLF receivers at Casa Cielo, Vieques Island, Puerto Rico (18.12 deg N, 65.50 deg W), which were operated continuously during the time period August 21- September 15, 2001. The narrowband measurements of the NAU (Aguadilla, Puerto Rico), NLK (Jim Creek, Washington) and NAA (Cutler, Maine) signals were performed every day from 1500UT to 1400UT while broadband recordings were made 1 minute out of every 5 minutes from 1630UT to 1000UT. In this talk we report observations of spectacular early/fast VLF events, which were detected on the 40.75 kHz NAU signal on multiple occasions during August 31, September 1, 2 and 13, 2001. The observed signal amplitude changes ranged from a fraction of a dB up to 19 dB, with both positive and negative field changes. The unusually large events were superposed on top of a very high degree of variability of signal amplitude, caused by the fact that the magnetic loop antenna was aligned to null the ground signal and was thus disposed to only detect the sky wave signal. Some of the observed events exhibited recovery signatures with duration on the order of several tens of seconds, while a subset of events did not exhibit clear recovery signatures, possibly

  12. Stalagmite stable isotope record of recent tropical cyclone events

    NASA Astrophysics Data System (ADS)

    Benoit Frappier, Amy; Sahagian, Dork; Carpenter, Scott J.; González, Luis A.; Frappier, Brian R.

    2007-02-01

    We present a 23 yr stalagmite record (1977 2000) of oxygen isotope variation, associated with 11 tropical cyclones (TCs), from Actun Tunichil Muknal cave in central Belize. High-resolution microsampling yielded a record of monthly to weekly temporal resolution that contains abrupt decreases (negative excursions) in calcite δ18O values that correspond with recent TC rain events nearby. A logistic discriminant model reliably identified TC proxy signals using the measurable parameters δ18O and δ13C values, and single point changes in δ18O value. The logistic model correctly identified 80% of excursions as TC events and incorrectly classified only 1 of nearly 1200 nonstorm sampling points. In addition to enabling high-resolution TC frequency reconstruction, this geologic proxy also provides information about the intensity of individual TCs. A multiple regression predicted TC intensity (R2 = 0.465, p = 0.034) using sampling frequency and excursion amplitude. Consistent with previous low-resolution studies, we found that the decadal average δ18O value was lower during the 1990s when several TCs produced rainfall in the area, but higher during the 1980s when only one TC struck. Longer, accurately dated, high-resolution speleothem stable isotope records may be a useful new tool for paleotempestology, to clarify associations between highly variable TC activity and the dynamic range of Quaternary climate.

  13. Public support for restrictions on fast food company sponsorship of community events.

    PubMed

    Pettigrew, Simone; Pescud, Melanie; Rosenberg, Michael; Ferguson, Renee; Houghton, Stephen

    2012-01-01

    This study investigated community attitudes to fast food companies' sponsorship of community events. The aim was to inform future efforts to introduce greater restrictions on these marketing activities to reduce child obesity. While previous research has focused on the sponsorship of sporting events, the present study included all community events and gauged public support for fast food company sponsorships in general as well as specific sponsorship activities such as securing event naming rights, advertising on event premises, and distributing free items to children in the form of food and redeemable vouchers. A large and diverse sample of Western Australian adults (n=2,005) responded to a community attitudes telephone survey that included questions relating to event sponsorship. Almost half of the respondents reported that the promotion of fast foods is inappropriate at community events, and only a third considered it appropriate at events where children are likely to be present. Around two-thirds agreed that promoting fast foods at such events sends contradictory messages to children and just a quarter of respondents considered it acceptable for free fast food to be distributed at events or for children to be rewarded for participation with fast food vouchers. The results suggest that efforts to reduce child obesity that involve restrictions on the sponsorship of community events by organisations promoting unhealthy foods may be supported by a substantial proportion of the population.

  14. Adverse-drug-event surveillance using narrative nursing records in electronic nursing records.

    PubMed

    Ahn, Hee-Jung; Park, Hyeoun-Ae

    2013-01-01

    The purpose of this study was to determine whether the frequency of adverse drug events can be extracted by analyzing narrative nursing statements documented in standardized terminology-based electronic nursing records. For this study, we reviewed the narrative nursing documentations of 487 admissions of 355 cancer patients who were treated with cisplatin at a tertiary-care hospital in Korea. Narrative nursing statements with the terms "adverse drug reaction," "allergy," "hypersensitivity," and other adverse drug events listed in the safety information were analyzed. In addition, nausea, one of the most frequent adverse drug events, was further examined. Narrative statements documenting the presence or absence of an "adverse drug reaction," "allergy," and "hypersensitivity" were found in 162 admissions (33.3%). The presence or absence of adverse drug events due to cisplatin was documented in 476 admissions (97.7%). At least one adverse drug event was noted in 258 admissions (53.0%). The presence of nausea was documented in 214 admissions (43.9%), and the mean duration of nausea was 5.2 days. The results of this study suggest that adverse drug events can be monitored using narrative nursing statements documented in standardized terminology-based electronic nursing records.

  15. Effective record length for the T-year event

    USGS Publications Warehouse

    Tasker, Gary D.

    1983-01-01

    The effect of serial dependence on the reliability of an estimate of the T-yr. event is of importance in hydrology because design decisions are based upon the estimate. In this paper the reliability of estimates of the T-yr. event from two common distributions is given as a function of number of observations and lag-one serial correlation coefficient for T = 2, 10, 20, 50, and 100 yr. A lag-one autoregressive model is assumed with either a normal or Pearson Type-III disturbance term. Results indicate that, if observations are serially correlated, the effective record length should be used to estimate the discharge associated with the expected exceedance probability. ?? 1983.

  16. An ultra-fast fiber optic pressure sensor for blast event measurements

    NASA Astrophysics Data System (ADS)

    Wu, Nan; Zou, Xiaotian; Tian, Ye; Fitek, John; Maffeo, Michael; Niezrecki, Christopher; Chen, Julie; Wang, Xingwei

    2012-05-01

    Soldiers who are exposed to explosions are at risk of suffering traumatic brain injury (TBI). Since the causal relationship between a blast and TBI is poorly understood, it is critical to have sensors that can accurately quantify the blast dynamics and resulting wave propagation through a helmet and skull that are imparted onto and inside the brain. To help quantify the cause of TBI, it is important to record transient pressure data during a blast event. However, very few sensors feature the capabilities of tracking the dynamic pressure transients due to the rapid change of the pressure during blast events, while not interfering with the physical material layers or wave propagation. In order to measure the pressure transients efficiently, a pressure sensor should have a high resonant frequency and a high spatial resolution. This paper describes an ultra-fast fiber optic pressure sensor based on the Fabry-Perot principle for the application of measuring the rapid pressure changes in a blast event. A shock tube experiment performed in US Army Natick Soldier Research, Development and Engineering Center has demonstrated that the resonant frequency of the sensor is 4.12 MHz, which is relatively close to the designed theoretical value of 4.113 MHz. Moreover, the experiment illustrated that the sensor has a rise time of 120 ns, which demonstrates that the sensor is capable of observing the dynamics of the pressure transient during a blast event.

  17. Impact of flood events on lacustrine carbonate isotope records

    NASA Astrophysics Data System (ADS)

    Kämpf, Lucas; Plessen, Birgit; Lauterbach, Stefan; Nantke, Carla; Meyer, Hanno; Chapligin, Bernhard; Höllerer, Hannes; Brauer, Achim

    2016-04-01

    Stable oxygen (δ 18O) and carbon (δ 13C) isotope compositions of lacustrine carbonates are among the most frequently used proxies in palaeolimnological / -environmental studies. Stable isotope analyses are often carried out on bulk carbonate samples, which are prone to contamination with detrital carbonates, transported into the lake by runoff processes and carrying the isotopic signal of catchment rocks, thus hampering the interpretation of the data in terms of past climatic and/or environmental changes. Despite the awareness of a likely detrital bias, the degree of contamination in most cases remains unknown and discrete contaminated samples undetected due to a lack of methods to disentangle endogenic and detrital carbonates in sediment records. To address this issue and provide more comprehensive insights into effects of flood-related detrital input on the bulk carbonate isotopic composition, we conducted stable isotope measurements on sediments trapped on a 3-12 day basis over a three-year period (January 2011 to November 2013) at two locations in pre-Alpine Lake Mondsee, close to the inflow of the main tributary and in the deepest part of the lake basin. Lake Mondsee was chosen for the monitoring since the pelagic sediments are annually laminated consisting of couplets of light calcite layers and dark layers made up by a mixture of detrital clastic and organic matter. Maximum calcite flux rates >1.5 g m2 d-1 were trapped between May and September, indicating the seasonal endogenic precipitation of calcite crystals. The comparison of the δ 18O composition of trapped carbonates, rain and epilimnion lake water revealed equilibrium calcite precipitation, allowing us to infer purely endogenic δ 18O (-9 to -11.3‰ VPDB) and δ 13C values (-6 to -9‰ VPDB) throughout the summer season. The endogenic calcite precipitation was interrupted by 14 peaks in carbonate flux (4 to 175 g m2 d-1) triggered by runoff events of different magnitudes (10-110 m3 s-1 peak

  18. Adaptive Sparse Signal Processing for Discrimination of Satellite-based Radiofrequency (RF) Recordings of Lightning Events

    NASA Astrophysics Data System (ADS)

    Moody, D. I.; Smith, D. A.; Heavner, M.; Hamlin, T.

    2014-12-01

    Ongoing research at Los Alamos National Laboratory studies the Earth's radiofrequency (RF) background utilizing satellite-based RF observations of terrestrial lightning. The Fast On-orbit Recording of Transient Events (FORTE) satellite, launched in 1997, provided a rich RF lightning database. Application of modern pattern recognition techniques to this dataset may further lightning research in the scientific community, and potentially improve on-orbit processing and event discrimination capabilities for future satellite payloads. We extend sparse signal processing techniques to radiofrequency (RF) transient signals, and specifically focus on improved signature extraction using sparse representations in data-adaptive dictionaries. We present various processing options and classification results for on-board discharges, and discuss robustness and potential for capability development.

  19. Algorithm for fast event parameters estimation on GEM acquired data

    NASA Astrophysics Data System (ADS)

    Linczuk, Paweł; Krawczyk, Rafał D.; Poźniak, Krzysztof T.; Kasprowicz, Grzegorz; Wojeński, Andrzej; Chernyshova, Maryna; Czarski, Tomasz

    2016-09-01

    We present study of a software-hardware environment for developing fast computation with high throughput and low latency methods, which can be used as back-end in High Energy Physics (HEP) and other High Performance Computing (HPC) systems, based on high amount of input from electronic sensor based front-end. There is a parallelization possibilities discussion and testing on Intel HPC solutions with consideration of applications with Gas Electron Multiplier (GEM) measurement systems presented in this paper.

  20. Exupery volcano fast response system - The event detection and waveform classification system

    NASA Astrophysics Data System (ADS)

    Hammer, Conny; Ohrnberger, Matthias

    2010-05-01

    Volcanic eruptions are often preceded by seismic activity which can be used to quantify the volcanic activity since the number and the size of certain types of seismic events usually increase before periods of volcanic crisis. The implementation of an automatic detection and classification system for seismic signals of volcanic origin allows not only for the processing of large amounts of data in short time, but also provides consistent and time-invariant results. Here, we have developed a system based upon a combination of different methods. To enable a first robust event detection in the continuous data stream different modules are implemented in the real time system Earthworm which is widely distributed in active volcano monitoring observatories worldwide. Among those software modules are classical trigger algorithm like STA/LTA and cross-correlation master event matching which is also used to detect different classes of signals. Furthermore an additional module is implemented in the real time system to compute continuous activity parameters which are also used to quantify the volcanic activity. Most automatic classification systems need a sufficiently large pre-classified data set for training the system. However in case of a volcanic crisis we are often confronted with a lack of training data due to insufficient prior observations because prior data acquisition might be carried out with different equipment at a low number of sites and due to the imminent crisis there might be no time for the time-consuming and tedious process of preparing a training data set. For this reason we have developed a novel seismic event spotting technique in order to be less dependent on the existence of previously acquired data bases of event classes. One main goal is therefore to provide observatory staff with a robust event classification based on a minimum number of reference waveforms. By using a "learning-while-recording" approach we are allowing for the fast build-up of a

  1. Adaptive sparse signal processing of satellite-based radio frequency (RF) recordings of lightning events

    NASA Astrophysics Data System (ADS)

    Moody, Daniela I.; Smith, David A.

    2014-05-01

    Ongoing research at Los Alamos National Laboratory studies the Earth's radio frequency (RF) background utilizing satellite-based RF observations of terrestrial lightning. Such impulsive events are dispersed through the ionosphere and appear as broadband nonlinear chirps at a receiver on-orbit. They occur in the presence of additive noise and structured clutter, making their classification challenging. The Fast On-orbit Recording of Transient Events (FORTE) satellite provided a rich RF lightning database. Application of modern pattern recognition techniques to this database may further lightning research in the scientific community, and potentially improve on-orbit processing and event discrimination capabilities for future satellite payloads. Conventional feature extraction techniques using analytical dictionaries, such as a short-time Fourier basis or wavelets, are not comprehensively suitable for analyzing the broadband RF pulses under consideration here. We explore an alternative approach based on non-analytical dictionaries learned directly from data, and extend two dictionary learning algorithms, K-SVD and Hebbian, for use with satellite RF data. Both algorithms allow us to learn features without relying on analytical constraints or additional knowledge about the expected signal characteristics. We then use a pursuit search over the learned dictionaries to generate sparse classification features, and discuss their performance in terms of event classification. We also use principal component analysis to analyze and compare the respective learned dictionary spaces to the real data space.

  2. Different event-related patterns of gamma-band power in brain waves of fast- and slow-reacting subjects.

    PubMed Central

    Jokeit, H; Makeig, S

    1994-01-01

    Fast- and slow-reacting subjects exhibit different patterns of gamma-band electroencephalogram (EEG) activity when responding as quickly as possible to auditory stimuli. This result appears to confirm long-standing speculations of Wundt that fast- and slow-reacting subjects produce speeded reactions in different ways and demonstrates that analysis of event-related changes in the amplitude of EEG activity recorded from the human scalp can reveal information about event-related brain processes unavailable using event-related potential measures. Time-varying spectral power in a selected (35- to 43-Hz) gamma frequency band was averaged across trials in two experimental conditions: passive listening and speeded reacting to binaural clicks, forming 40-Hz event-related spectral responses. Factor analysis of between-subject event-related spectral response differences split subjects into two near-equal groups composed of faster- and slower-reacting subjects. In faster-reacting subjects, 40-Hz power peaked near 200 ms and 400 ms poststimulus in the react condition, whereas in slower-reacting subjects, 40-Hz power just before stimulus delivery was larger in the react condition. These group differences were preserved in separate averages of relatively long and short reaction-time epochs for each group. gamma-band (20-60 Hz)-filtered event-related potential response averages did not differ between the two groups or conditions. Because of this and because gamma-band power in the auditory event-related potential is small compared with the EEG, the observed event-related spectral response features must represent gamma-band EEG activity reliably induced by, but not phase-locked to, experimental stimuli or events. PMID:8022783

  3. Ca(2+) release events in cardiac myocytes up close: insights from fast confocal imaging.

    PubMed

    Shkryl, Vyacheslav M; Blatter, Lothar A

    2013-01-01

    The spatio-temporal properties of Ca(2+) transients during excitation-contraction coupling and elementary Ca(2+) release events (Ca(2+) sparks) were studied in atrial and ventricular myocytes with ultra-fast confocal microscopy using a Zeiss LSM 5 LIVE system that allows sampling rates of up to 60 kHz. Ca(2+) sparks which originated from subsarcolemmal junctional sarcoplasmic reticulum (j-SR) release sites in atrial myocytes were anisotropic and elongated in the longitudinal direction of the cell. Ca(2+) sparks in atrial cells originating from non-junctional SR and in ventricular myocytes were symmetrical. Ca(2+) spark recording in line scan mode at 40,000 lines/s uncovered step-like increases of [Ca(2+)]i. 2-D imaging of Ca(2+) transients revealed an asynchronous activation of release sites and allowed the sequential recording of Ca(2+) entry through surface membrane Ca(2+) channels and subsequent activation of Ca(2+)-induced Ca(2+) release. With a latency of 2.5 ms after application of an electrical stimulus, Ca(2+) entry could be detected that was followed by SR Ca(2+) release after an additional 3 ms delay. Maximum Ca(2+) release was observed 4 ms after the beginning of release. The timing of Ca(2+) entry and release was confirmed by simultaneous [Ca(2+)]i and membrane current measurements using the whole cell voltage-clamp technique. In atrial cells activation of discrete individual release sites of the j-SR led to spatially restricted Ca(2+) release events that fused into a peripheral ring of elevated [Ca(2+)]i that subsequently propagated in a wave-like fashion towards the center of the cell. In ventricular myocytes asynchronous Ca(2+) release signals from discrete sites with no preferential subcellular location preceded the whole-cell Ca(2+) transient. In summary, ultra-fast confocal imaging allows investigation of Ca(2+) signals with a time resolution similar to patch clamp technique, however in a less invasive fashion.

  4. Development of a Fast Response Intake Air Temperature Recorder for the Mirage IIIO Aircraft.

    DTIC Science & Technology

    1986-02-01

    noise, but is otherwise a faithful reproduction of the thermocouple response. 9. CONCLUSIONS An intake air temperature probe and associated recording...DEVELOPMENT OF A FAST RESPONSE INTAKE AIR TEMPERATI*1E RECORDER FOR THE MIRAGE 1110 AIRCRAFT by W. H. HARCH DT1C EE ECTIZNV 12 N8 L B Approved for...Propulsion Technical Memorandum 433" DEVELOPMENT OF A FAST RESPONSE INTAKE AIR TEMPEATURE RECORDER FOR TlE MIRAGE I1IO AIRCRAFT by W.H. HARCH SUIMARY

  5. Applications Of Fast And Slow Streak Recording Cameras

    NASA Astrophysics Data System (ADS)

    Davidhazy, Andrew

    1988-02-01

    This paper deals with two applications of streak photography in everyday industrial and biological research and development endeavors. In each instance, the simplicity and low cost with which the data could be reduced to useful information and the ease with which it could be communicated to other technical personnel was an important side benefit. In the first case, a laboratory built rotating drum streak camera with a 12" circumference, was used to study the performance of the new Olympus F280 flash on an Olympus 0M4-T camera. The strobing frequency, starting characteristics, duration under manual and camera control, flash relationship to shutter curtain position, flash initiation and curtain velocities were examined. In the second case, a standard oscilloscope recording camera was modified to study the growth characteristics of a fungus culture growing under controlled laboratory conditions for periods up to one full week. The streak photographs, taken at ultra slow rates, were correlated with 2-dimensional photographs taken at regular intervals to eliminate ambiguity in the growth cycle whe the photographs were included in a written report.

  6. Patient records: from single events to elements for health planning.

    PubMed

    Pisanelli, D M; Ricci, F L

    1994-12-01

    Data collected in patient records are not only the kernel of a ward information system, but also the groundwork for planning and evaluating services in health care. The aim of this study was to analyze the problem of aggregate data generation starting from separate items in patient records. After describing the different uses of patient record data, we outline the process which generates aggregates data starting from individual records. This process leads to the definition of the "view on aggregation" as an intermediate step between patient records and aggregate data. A simplified schema is presented based on the Entity-Relationship model representing a conceptual model of the integration of aggregate data and patient record items. Finally, the role is discussed of automation in this process and the perspectives for its implementation.

  7. Demanding response time requirements on coherent receivers due to fast polarization rotations caused by lightning events.

    PubMed

    Krummrich, Peter M; Ronnenberg, David; Schairer, Wolfgang; Wienold, Daniel; Jenau, Frank; Herrmann, Maximilian

    2016-05-30

    Lightning events can cause fast polarization rotations and phase changes in optical transmission fibers due to strong electrical currents and magnetic fields. Whereas these are unlikely to affect legacy transmission systems with direct detection, different mechanisms have to be considered in systems with local oscillator based coherent receivers and digital signal processing. A theoretical analysis reveals that lightning events can result in polarization rotations with speeds as fast as a few hundred kRad/s. We discuss possible mechanisms how such lightning events can affect coherent receivers with digital signal processing. In experimental investigations with a high current pulse generator and transponder prototypes, we observed post FEC errors after polarization rotation events which can be expected from lightning strikes.

  8. Controls on Flood Event Frequencies Recorded in Stalagmites from Cave KNI-51, Australian Tropics

    NASA Astrophysics Data System (ADS)

    Denniston, Rhawn; Gonzales, Angelique; Villarini, Gabriele; Polyak, Victor; Asmerom, Yemane; Wanamaker, Alan, Jr.; Lachniet, Matthew; Ummenhofer, Caroline; Cugley, John; Woods, David; Humphreys, William

    2016-04-01

    Extreme rainfall events in the central Australia tropics are largely driven by tropical cyclones and the Australian summer monsoon, both of which are sensitive to external forcing. To better understand baseline variability in extreme rainfall, we produced a record of cave flooding events spanning the last two millennia from a suite of precisely-dated and fast-growing aragonite stalagmites from cave KNI-51 (Denniston et al., 2015, PNAS, 112, 4576). During cave flooding events, sediment deposited on stalagmite surfaces becomes preserved within the stalagmite when floodwaters recede and stalagmite growth resumes. Ages of individual flood events are determined using growth models constructed from linear interpolation of 230Th-dated intervals of stalagmite carbonate (2 s.d. errors of ±1-30 yr in most cases). The robustness of this stalagmite flood record was tested, in part, by comparing accumulations of sediment layers in coeval stalagmites. Absolute values and temporal trends in flood recurrence rates were generally quite similar between stalagmites, arguing that each stalagmite was equally sensitive to flood events. We have now extended this cave flooding record back to 3600 yr BP using three additional stalagmites, each of which contains multi-decadal to centennial variations in flood frequency. The longest duration (1000 yr) and tallest (1.1m) of these stalagmites, KNI-51-7, is marked by a secular trend toward reduced flood occurrence rates, with the 30 yr running mean of floods/yr reaching 0.0, a value lower than in any other of the other nine samples analyzed in this study. However, KNI-51-N, which overlaps with KNI-51-7 for 300 yr, contains nearly identical sub-centennial variations to KNI-51-7 but KNI-51-N does not trend toward lower values. We argue that the decreasing average number of flood events with time in KNI-51-7 is a result of the stalagmite having grown above average flood height, thereby restricting its ability to record more frequent, smaller

  9. Active Region Coronal Rain Event Observed by the Fast Imaging Solar Spectrograph on the NST

    NASA Astrophysics Data System (ADS)

    Ahn, Kwangsu; Chae, Jongchul; Cho, Kyung-Suk; Song, Donguk; Yang, Heesu; Goode, Philip R.; Cao, Wenda; Park, Hyungmin; Nah, Jakyung; Jang, Bi-Ho; Park, Young-Deuk

    2014-11-01

    The Fast Imaging Solar Spectrograph (FISS) is being operated on the New Solar Telescope of the Big Bear Solar Observatory. It simultaneously records spectra of Hα and Ca ii 8542 Å lines, and this dual-spectra measurement provides an estimate of the temperature and nonthermal speed components. We observed a loop structure in AR 11305 using the FISS, SDO/AIA, and STEREO/EUVI in 304 Å, and found plasma material falling along the loop from a coronal height into the umbra of a sunspot, which accelerated up to 80 km s-1. We also observed C2 and C7 flare events near the loop. The temperature of the downflows was in the range of 10 000 - 33 000 K, increasing toward the umbra. The temperature of the flow varied with time, and the temperature near the footpoint rose immediately after the C7 flare, but the temperature toward the umbra remained the same. There seemed to be a temporal correlation between the amount of downflow material and the observed C-class flares. The downflows decreased gradually soon after the flares and then increased after a few hours. These high-speed red-shift events occurred continuously during the observations. The flows observed on-disk in Hα and Ca ii 8542 Å appeared as fragmented, fuzzy condensed material falling from the coronal heights when seen off-limb with STEREO/EUVI at 304 Å. Based on these observations, we propose that these flows were an on-disk signature of coronal rain.

  10. A Comparison of Elemental Abundance Ratios in SEP Events in Fast and Slow Solar Wind Regions

    DTIC Science & Technology

    2009-07-24

    that the elemental abundances of gradual SEP events reflect the composition of the solar corona , implying that the ambient coronal thermal ions...point at the top of the corona , although the plasma near Earth emerged ~4 days prior to its arrival at 1 AU. Thus energetic-particle and solar -wind...TYPE REPRINT 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE A Comparison of Elemental Abundance Ratios in SEP Events in Fast and Slow Solar

  11. LIMITS ON THE EVENT RATES OF FAST RADIO TRANSIENTS FROM THE V-FASTR EXPERIMENT

    SciTech Connect

    Wayth, Randall B.; Tingay, Steven J.; Deller, Adam T.; Brisken, Walter F.; Thompson, David R.; Wagstaff, Kiri L.; Majid, Walid A.

    2012-07-10

    We present the first results from the V-FASTR experiment, a commensal search for fast transient radio bursts using the Very Long Baseline Array (VLBA). V-FASTR is unique in that the widely spaced VLBA antennas provide a discriminant against non-astronomical signals and a mechanism for the localization and identification of events that is not possible with single dishes or short baseline interferometers. Thus, far V-FASTR has accumulated over 1300 hr of observation time with the VLBA, between 90 cm and 3 mm wavelength (327 MHz-86 GHz), providing the first limits on fast transient event rates at high radio frequencies (>1.4 GHz). V-FASTR has blindly detected bright individual pulses from seven known pulsars but has not detected any single-pulse events that would indicate high-redshift impulsive bursts of radio emission. At 1.4 GHz, V-FASTR puts limits on fast transient event rates comparable with the PALFA survey at the Arecibo telescope, but generally at lower sensitivities, and comparable to the 'fly's eye' survey at the Allen Telescope Array, but with less sky coverage. We also illustrate the likely performance of the Phase 1 SKA dish array for an incoherent fast transient search fashioned on V-FASTR.

  12. Record-breaking events during the compressive failure of porous materials

    NASA Astrophysics Data System (ADS)

    Pál, Gergő; Raischel, Frank; Lennartz-Sassinek, Sabine; Kun, Ferenc; Main, Ian G.

    2016-03-01

    An accurate understanding of the interplay between random and deterministic processes in generating extreme events is of critical importance in many fields, from forecasting extreme meteorological events to the catastrophic failure of materials and in the Earth. Here we investigate the statistics of record-breaking events in the time series of crackling noise generated by local rupture events during the compressive failure of porous materials. The events are generated by computer simulations of the uniaxial compression of cylindrical samples in a discrete element model of sedimentary rocks that closely resemble those of real experiments. The number of records grows initially as a decelerating power law of the number of events, followed by an acceleration immediately prior to failure. The distribution of the size and lifetime of records are power laws with relatively low exponents. We demonstrate the existence of a characteristic record rank k*, which separates the two regimes of the time evolution. Up to this rank deceleration occurs due to the effect of random disorder. Record breaking then accelerates towards macroscopic failure, when physical interactions leading to spatial and temporal correlations dominate the location and timing of local ruptures. The size distribution of records of different ranks has a universal form independent of the record rank. Subsequences of events that occur between consecutive records are characterized by a power-law size distribution, with an exponent which decreases as failure is approached. High-rank records are preceded by smaller events of increasing size and waiting time between consecutive events and they are followed by a relaxation process. As a reference, surrogate time series are generated by reshuffling the event times. The record statistics of the uncorrelated surrogates agrees very well with the corresponding predictions of independent identically distributed random variables, which confirms that temporal and spatial

  13. Fast-track extreme event attribution: How fast can we disentangle thermodynamic (forced) and dynamic (internal) contributions?

    NASA Astrophysics Data System (ADS)

    Haustein, Karsten; Otto, Friederike; Uhe, Peter; Allen, Myles; Cullen, Heidi

    2016-04-01

    provide sufficient guidance to determine the dynamic contribution to the event on the basis of monthly mean values. No such link can be made (North Atlantic/Western Europe region) for shorter time-scales, unless the observed state of the circulation is taken as reference for the model analysis (e.g. Christidis et al. 2014). We present results from our most recent attribution analysis for the December 2015 UK floods (Storm Desmond and Eva), during which we find a robust teleconnection link between Pacific SSTs and North Atlantic Jetstream anomalies. This is true for both experiments, with forecast and observed SSTs. We propose a fast and simple analysis method based on the comparison of current climatological circulation patterns with actual and natural conditions. Alternative methods are discussed and analysed regarding their potential for fast-track attribution of the role of dynamics. Also, we briefly revisit the issue of internal vs forced dynamic contributions.

  14. Safety design approach for external events in Japan sodium-cooled fast reactor

    SciTech Connect

    Yamano, H.; Kubo, S.; Tani, A.; Nishino, H.; Sakai, T.

    2012-07-01

    This paper describes a safety design approach for external events in the design study of Japan sodium-cooled fast reactor. An emphasis is introduction of a design extension external condition (DEEC). In addition to seismic design, other external events such as tsunami, strong wind, abnormal temperature, etc. were addressed in this study. From a wide variety of external events consisting of natural hazards and human-induced ones, a screening method was developed in terms of siting, consequence, frequency to select representative events. Design approaches for these events were categorized on the probabilistic, statistical and deterministic basis. External hazard conditions were considered mainly for DEECs. In the probabilistic approach, the DEECs of earthquake, tsunami and strong wind were defined as 1/10 of exceedance probability of the external design bases. The other representative DEECs were also defined based on statistical or deterministic approaches. (authors)

  15. 49 CFR Appendix D to Part 229 - Criteria for Certification of Crashworthy Event Recorder Memory Module

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Criteria for Certification of Crashworthy Event... STANDARDS Pt. 229, App. D Appendix D to Part 229—Criteria for Certification of Crashworthy Event Recorder Memory Module Section 229.135(b) requires that certain locomotives be equipped with an event...

  16. Mars Tharsis region - Volcanotectonic events in the stratigraphic record

    NASA Technical Reports Server (NTRS)

    Scott, D. H.; Tanaka, K. L.

    1980-01-01

    It is pointed out that the most recent volcanism and much of the oldest tectonic activity on Mars have apparently occurred within the Tharsis region. Detailed geologic mapping from Viking images has provided new information on the evolutionary history of the region. The eruptive sequence and areal extent of lava flows in the Tharsis region have been defined by stratigraphic studies and crater counts made on individual flow units. Faults and fractures transecting these units provide a record of changing tectonic intensity during the period of high volcanic activity. Volcanism began with the resurfacing of basement rocks early in the history of the region and continued without large interruptions through nine major eruptive episodes. Volcanic centers shifted from place to place but resurgent activity occurred at several volcanoes. Volcanism culminated during the foration of large shield volcanoes along Tharsis Montes and thereafter appears to have gradually declined.

  17. Intracranial Recordings of Occipital Cortex Responses to Illusory Visual Events.

    PubMed

    de Jong, Maartje C; Hendriks, Ralph J M; Vansteensel, Mariska J; Raemaekers, Mathijs; Verstraten, Frans A J; Ramsey, Nick F; Erkelens, Casper J; Leijten, Frans S S; van Ee, Raymond

    2016-06-08

    Ambiguous visual stimuli elicit different perceptual interpretations over time, creating the illusion that a constant stimulus is changing. We investigate whether such spontaneous changes in visual perception involve occipital brain regions specialized for processing visual information, despite the absence of concomitant changes in stimulation. Spontaneous perceptual changes observed while viewing a binocular rivalry stimulus or an ambiguous structure-from-motion stimulus were compared with stimulus-induced perceptual changes that occurred in response to an actual stimulus change. Intracranial recordings from human occipital cortex revealed that spontaneous and stimulus-induced perceptual changes were both associated with an early transient increase in high-frequency power that was more spatially confined than a later transient decrease in low-frequency power. We suggest that the observed high-frequency and low-frequency modulations relate to initiation and maintenance of a percept, respectively. Our results are compatible with the idea that spontaneous changes in perception originate from competitive interactions within visual neural networks. Ambiguous visual stimuli elicit different perceptual interpretations over time, creating the illusion that a constant stimulus is changing. The literature on the neural correlates of conscious visual perception remains inconclusive regarding the extent to which such spontaneous changes in perception involve sensory brain regions. In an attempt to bridge the gap between existing animal and human studies, we recorded from intracranial electrodes placed on the human occipital lobe. We compared two different kinds of ambiguous stimuli, binocular rivalry and the phenomenon of ambiguous structure-from-motion, enabling generalization of our findings across different stimuli. Our results indicate that spontaneous and stimulus-induced changes in perception (i.e., "illusory" and "real" changes in the stimulus, respectively) may

  18. DEFLECTIONS OF FAST CORONAL MASS EJECTIONS AND THE PROPERTIES OF ASSOCIATED SOLAR ENERGETIC PARTICLE EVENTS

    SciTech Connect

    Kahler, S. W.; Akiyama, S.; Gopalswamy, N.

    2012-08-01

    The onset times and peak intensities of solar energetic particle (SEP) events at Earth have long been thought to be influenced by the open magnetic fields of coronal holes (CHs). The original idea was that a CH lying between the solar SEP source region and the magnetic footpoint of the 1 AU observer would result in a delay in onset and/or a decrease in the peak intensity of that SEP event. Recently, Gopalswamy et al. showed that CHs near coronal mass ejection (CME) source regions can deflect fast CMEs from their expected trajectories in space, explaining the appearance of driverless shocks at 1 AU from CMEs ejected near solar central meridian (CM). This suggests that SEP events originating in CME-driven shocks may show variations attributable to CH deflections of the CME trajectories. Here, we use a CH magnetic force parameter to examine possible effects of CHs on the timing and intensities of 41 observed gradual E {approx} 20 MeV SEP events with CME source regions within 20 Degree-Sign of CM. We find no systematic CH effects on SEP event intensity profiles. Furthermore, we find no correlation between the CME leading-edge measured position angles and SEP event properties, suggesting that the widths of CME-driven shock sources of the SEPs are much larger than the CMEs. Independently of the SEP event properties, we do find evidence for significant CME deflections by CH fields in these events.

  19. Deflections of Fast Coronal Mass Ejections and the Properties of Associated Solar Energetic Particle Events

    NASA Technical Reports Server (NTRS)

    Kahler, S. W.; Akiyama, S.; Gopalswamy, N.

    2012-01-01

    The onset times and peak intensities of solar energetic particle (SEP) events at Earth have long been thought to be influenced by the open magnetic fields of coronal holes (CHs). The original idea was that a CH lying between the solar SEP source region and the magnetic footpoint of the 1 AU observer would result in a delay in onset and/or a decrease in the peak intensity of that SEP event. Recently, Gopalswamy et al. showed that CHs near coronal mass ejection (CME) source regions can deflect fast CMEs from their expected trajectories in space, explaining the appearance of driverless shocks at 1 AU from CMEs ejected near solar central meridian (CM). This suggests that SEP events originating in CME-driven shocks may show variations attributable to CH deflections of the CME trajectories. Here, we use a CH magnetic force parameter to examine possible effects of CHs on the timing and intensities of 41 observed gradual E approx 20 MeV SEP events with CME source regions within 20 deg. of CM. We find no systematic CH effects on SEP event intensity profiles. Furthermore, we find no correlation between the CME leading-edge measured position angles and SEP event properties, suggesting that the widths of CME-driven shock sources of the SEPs are much larger than the CMEs. Independently of the SEP event properties, we do find evidence for significant CME deflections by CH fields in these events

  20. FAST EVENTS IN PROTEIN FOLDING: The Time Evolution of Primary Processes

    NASA Astrophysics Data System (ADS)

    Callender, Robert H.; Dyer, R. Brian; Gilmanshin, Rudolf; Woodruff, William H.

    1998-10-01

    Most experimental studies on the dynamics of protein folding have been confined to timescales of 1 ms and longer. Yet it is obvious that many phenomena that are obligatory elements of the folding process occur on much faster timescales. For example, it is also now clear that the formation of secondary and tertiary structures can occur on nanosecond and microsecond times, respectively. Although fast events are essential to, and sometimes dominate, the overall folding process, with a few exceptions their experimental study has become possible only recently with the development of appropriate techniques. This review discusses new approaches that are capable of initiating and monitoring the fast events in protein folding with temporal resolution down to picoseconds. The first important results from those techniques, which have been obtained for the folding of some globular proteins and polypeptide models, are also discussed.

  1. Scoring polysomnography respiratory events: the utility of nasal pressure and oro-nasal thermal sensor recordings.

    PubMed

    Teichtahl, Harry; Cunnington, David; Cherry, Gaye; Wang, David

    2003-09-01

    To evaluate the clinical utility of nasal cannula/pressure (NP) and oro-nasal thermal sensor (Th) recordings, alone and in combination for scoring respiratory events during routine diagnostic polysomnography (PSG). The use of Th devices to measure airflow during PSG is not recommended because Th are insensitive to airflow changes other then complete airflow cessation. It has been suggested that NP recording is a better measure of airflow and can also detect increased upper airway resistance during PSG. Thirty consecutive PSG's were examined using 13 standard channels including Th and NP recordings. Respiratory events were scored separately utilizing NP+Th, Th alone and NP alone in a blinded fashion using modified AASM criteria. Respiratory events were time matched to within 5 s for each of the recording methods. NP+Th detected more events than Th alone (P<0.0001); NP+Th detected more events than NP alone (P<0.0001) and NP alone detected more events than Th alone (P<0.0001). For AHI >50, NP alone and Th alone each detected 90% of matched NP+Th events. However, for AHI <50, NP alone detects 54% and Th alone detects 42% (P<0.005) of matched NP+Th events. For AHI >50, NP alone scored 97% of matched Th alone scored respiratory events, and Th alone scored 94% of NP alone scored respiratory events (P>0.05). However, for AHI<50, NP alone scored 90% of matched Th alone scored respiratory events, whereas Th alone scored 62% of matched NP alone scored events (P<0.0001). In severe sleep disordered breathing (AHI >50), NP+Th, NP alone and Th alone have similar ability to detect respiratory events. When AHI <50, NP+Th appears better for detecting respiratory events than NP or Th alone. If only one measure of airflow is used, NP detects more events than Th.

  2. Fast ion generation and runaway through magnetic reconnection events in MST

    NASA Astrophysics Data System (ADS)

    Kim, Jungha; Anderson, Jay; Capecchi, William; Bonofiglo, Phillip; Sears, Stephanie

    2016-10-01

    Fokker-Planck and full orbit modeling are used to investigate how global reconnection events in MST plasmas generate an anisotropic fast ion distribution. A multi-step process is hypothesized. First, thermal ions are heated by a perpendicular heating mechanism, possibly a stochastic process that relies on turbulent diffusion and strong radial electric fields, or ion cyclotron damping in the tearing-driven turbulent cascade. Second, a small fraction of the heated ions have sufficient speed to develop substantial guiding center drifts that are relatively immune to stochastic magnetic transport. In the RFP, these fast ion drift orbits are favorable to confinement. Finally, these fast ions are accelerated by a parallel inductive electric field (up to 80 V/m) associated with the abruptly changing magnetic equilibrium. This strong impulsive field does not include any magnetic-fluctuation-based contribution as experienced by thermal particles or electrons, which do not run away like fast ions. CQL3D, a Fokker-Planck solver, and RIO, a full orbit tracing code, are used to model this multi-step process that is responsible for anisotropy in fast ion distribution in MST. Work supported by US DOE. Supported by US DOE.

  3. ANTARES explosion as recorded by the US-ARRAY: an unprecedented ground-truth infrasound event

    NASA Astrophysics Data System (ADS)

    Vergoz, Julien; Millet, Christophe; Le Pichon, Alexis

    2016-04-01

    The 28th October 2014 in Wallops Flight Facility, orbital's Antares launch vehicle failed and heavily exploded onto the launch pad area. At that time, the US transportable array of more than 200 operating stations (all equipped with microbarometers), was located on the east coast of the US and surrounded the accident. A large amount and variety of infrasound phases were observed at some stations, highlighting interesting propagation effects. The variety of recorded signals on such a dense network is unprecedented and offers the opportunity to better understand some propagation features, such as (1) the frequency content changes of stratospheric phases; (2) the dispersion of tropospheric phases propagating over thousands of kilometers within a stable and thin waveguide at fast phase speeds (350m/s) with low attenuation; (3) the non-linear effects associated with slow thermospheric phases (180m/s), especially in terms of shape, amplitude and duration. These 3 points will be addressed, and pieces of interpretations will be given thanks to the different propagation techniques: full waveform modelling (Normal Modes, finite element method), parabolic equation and ray tracing technique. Location issues of such an acoustic event based on tens of infrasound arrival times only will also be shown and discussed.

  4. Event Management of RFID Data Streams: Fast Moving Consumer Goods Supply Chains

    NASA Astrophysics Data System (ADS)

    Mo, John P. T.; Li, Xue

    Radio Frequency Identification (RFID) is a wireless communication technology that uses radio-frequency waves to transfer information between tagged objects and readers without line of sight. This creates tremendous opportunities for linking real world objects into a world of "Internet of things". Application of RFID to Fast Moving Consumer Goods sector will introduce billions of RFID tags in the world. Almost everything is tagged for tracking and identification purposes. This phenomenon will impose a new challenge not only to the network capacity but also to the scalability of processing of RFID events and data. This chapter uses two national demonstrator projects in Australia as case studies to introduce an event managementframework to process high volume RFID data streams in real time and automatically transform physical RFID observations into business-level events. The model handles various temporal event patterns, both simple and complex, with temporal constraints. The model can be implemented in a data management architecture that allows global RFID item tracking and enables fast, large-scale RFID deployment.

  5. Temporal-spatial heterogeneity of under-recording of volcanic events in Japan

    NASA Astrophysics Data System (ADS)

    Kiyosugi, Koji

    2016-04-01

    Under-recording of events must be taken into account in estimating recurrence rates of explosive eruptions using volcanic eruption record. In the Large Magnitude Explosive Volcanic Eruptions (LaMEVE) database (Crosweller et al., 2012, Brown et al., 2014), Japanese events account for about 39 % of the entire set of eruptive events (Kiyosugi et al., 2015). An analysis of the Japanese eruption events show an inverse correlation between VEI and degree of under-reporting suggesting that even larger VEI eruptions are under-recorded in the Quaternary. For example, 89 % of VEI 4 events, 65-66 % of VEI 5 events, 46-49 % of VEI 6 events and 36-39 % of VEI 7 events are missing from the record at 100 ka, 200 ka, 300 ka, and 500 ka, respectively (Kiyosugi et al., 2015). Comparison of frequencies of Japanese and global eruptions suggests that under-recording of the global database is 7.9-8.7 times larger than in the Japanese dataset (Kiyosugi et al., 2015). In addition to the analysis of the entire Japanese eruption events, temporal-spatial heterogeneity of the dataset must be considered in modeling the under-recording of events. The main mechanisms of under-recording are absence of historical records, erosion and alteration of tephra deposits, burial of tephra deposits by younger deposits and disappearance of the source volcano itself due to burial or erosion. Therefore, under-recording of events varies temporally and spatially, reflecting geological and historical backgrounds. For example, an analysis of the Japanese eruption events suggest that many large eruptions are missing in the Izu-Bonin arc because the volcanic arc consists of small volcanic islands where wide-spread tephra deposits are less likely preserved. Understandings of the under-recording in different geological settings improve the estimation of recurrence rate of volcanic eruptions. Furthermore, Koyama (1999) pointed out that the historical record of Japanese volcanic eruptions increases in two time periods

  6. Time accuracy of a barcode system for recording resuscitation events: laboratory trials.

    PubMed

    Stewart, J A; Short, F A

    1999-11-01

    Barcode systems for recording clinical data from resuscitation attempts offer the prospect of more complete and time-accurate data collection; in addition, collection of data in digital form and the resulting ease of computer processing promises to facilitate data analysis for quality improvement and research. We conducted trials of such a barcode system, recording events during a videotaped, simulated in-hospital resuscitation, with particular attention to time accuracy. Nine subjects watched a videotape of a simulated cardiac resuscitation, recording events first with the barcode system and then with a conventional handwritten form. Recorded times were compared to an accurate record of events (gold standard) from the videotape. Mean absolute errors and standard deviations of errors from the gold standard were significantly smaller with the barcode system (P < 0.01 for both). Numbers of event omissions did not differ significantly. The barcode system is more accurate than conventional handwritten recording in capturing event times from a simulated resuscitation. The system shows promise as a means to improve time accuracy of resuscitation records.

  7. A fast event preprocessor for the Simbol-X Low-Energy Detector

    NASA Astrophysics Data System (ADS)

    Schanz, T.; Tenzer, C.; Kendziorra, E.; Santangelo, A.

    2008-07-01

    The Simbol-X1 Low Energy Detector (LED), a 128 × 128 pixel DEPFET array, will be read out very fast (8000 frames/second). This requires a very fast onboard data preprocessing of the raw data. We present an FPGA based Event Preprocessor (EPP) which can fulfill this requirements. The design is developed in the hardware description language VHDL and can be later ported on an ASIC technology. The EPP performs a pixel related offset correction and can apply different energy thresholds to each pixel of the frame. It also provides a line related common-mode correction to reduce noise that is unavoidably caused by the analog readout chip of the DEPFET. An integrated pattern detector can block all invalid pixel patterns. The EPP has an internal pipeline structure and can perform all operation in realtime (< 2 μs per line of 64 pixel) with a base clock frequency of 100 MHz. It is utilizing a fast median-value detection algorithm for common-mode correction and a new pattern scanning algorithm to select only valid events. Both new algorithms were developed during the last year at our institute.

  8. Event-related fast optical signal in a rapid object recognition task: improving detection by the independent component analysis.

    PubMed

    Medvedev, Andrei V; Kainerstorfer, Jana; Borisov, Sergey V; Barbour, Randall L; VanMeter, John

    2008-10-21

    Noninvasive recording of fast optical signals presumably reflecting neuronal activity is a challenging task because of a relatively low signal-to-noise ratio. To improve detection of those signals in rapid object recognition tasks, we used the independent component analysis (ICA) to reduce "global interference" (heartbeat and contribution of superficial layers). We recorded optical signals from the left prefrontal cortex in 10 right-handed participants with a continuous-wave instrument (DYNOT, NIRx, Brooklyn, NY). Visual stimuli were pictures of urban, landscape and seashore scenes with various vehicles as targets (target-to-non-target ratio 1:6) presented at ISI=166 ms or 250 ms. Subjects mentally counted targets. Data were filtered at 2-30 Hz and artifactual components were identified visually (for heartbeat) and using the ICA weight matrix (for superficial layers). Optical signals were restored from the ICA components with artifactual components removed and then averaged over target and non-target epochs. After ICA processing, the event-related response was detected in 70%-100% of subjects. The refined signal showed a significant decrease from baseline within 200-300 ms after targets and a slight increase after non-targets. The temporal profile of the optical signal corresponded well to the profile of a "differential ERP response", the difference between targets and non-targets which peaks at 200 ms in similar object detection tasks. These results demonstrate that the detection of fast optical responses with continuous-wave instruments can be improved through the ICA method capable to remove noise, global interference and the activity of superficial layers. Fast optical signals may provide further information on brain processing during higher-order cognitive tasks such as rapid categorization of objects.

  9. A COMPARISON OF ELEMENTAL ABUNDANCE RATIOS IN SEP EVENTS IN FAST AND SLOW SOLAR WIND REGIONS

    SciTech Connect

    Kahler, S. W.; Tylka, A. J.; Reames, D. V.

    2009-08-10

    The solar energetic (E > 1 MeV nucleon{sup -1}) particles (SEPs) observed in gradual events at 1 AU are assumed to be accelerated by coronal/interplanetary shocks from ambient thermal or suprathermal seed particles. If so, then the elemental abundances of SEPs produced in different solar wind (SW) stream types (transient, fast, and slow) might be systematically distinguished from each other. We look for these differences in SEP energy spectra and in elemental abundance ratios (including Mg/Ne and Fe/C, which compare low/high first ionization potential elements), in a large number of SEP time intervals over the past solar cycle. The SW regions are characterized by the three-component stream classification of Richardson et al. Our survey shows no significant compositional or energy spectral differences in the 5-10 MeV nucleon{sup -1} range for SEP events of different SW stream types. This result extends the earlier finding that SEP events are observed frequently in fast SW streams, although their higher Alfven and SW flow speeds should constrain SEP production by coronal mass ejection-driven shocks in those regions. We discuss the implications of our results for shock seed populations and cross-field propagation.

  10. Methods of and apparatus for recording images occurring just prior to a rapid, random event

    SciTech Connect

    Kelley, E.F.

    1994-04-05

    An apparatus and a method are disclosed for recording images of events in a medium wherein the images that are recorded are of conditions existing just prior to and during the occurrence of an event that triggers recording of these images. The apparatus and method use an optical delay path that employs a spherical focusing mirror facing a circular array of flat return mirrors around a central flat mirror. The image is reflected in a symmetric pattern which balances astigmatism which is created by the spherical mirror. Delays on the order of hundreds of nanoseconds are possible. 11 figures.

  11. Methods of and apparatus for recording images occurring just prior to a rapid, random event

    SciTech Connect

    Kelley, E.F.

    1991-12-31

    An apparatus and a method are disclosed for recording images of events in a medium wherein the images that are recorded are of conditions existing just prior to and during the occurrence of an event that triggers recording of these images. The apparatus and method use an optical delay path that employs a spherical focusing mirror facing a circular array of flat return mirrors around a central flat mirror. The image is reflected in a symmetric pattern which balances astigmatism which is created by the spherical mirror. Delays on the order of hundreds of nanoseconds are possible.

  12. Methods of and apparatus for recording images occurring just prior to a rapid, random event

    DOEpatents

    Kelley, Edward F.

    1994-01-01

    An apparatus and a method are disclosed for recording images of events in a medium wherein the images that are recorded are of conditions existing just prior to and during the occurrence of an event that triggers recording of these images. The apparatus and method use an optical delay path that employs a spherical focusing mirror facing a circular array of flat return mirrors around a central flat mirror. The image is reflected in a symmetric pattern which balances astigmatism which is created by the spherical mirror. Delays on the order of hundreds of nanoseconds are possible.

  13. A Fast Event Preprocessor and Sequencer for the Simbol-X Low Energy Detector

    SciTech Connect

    Schanz, T.; Tenzer, C.; Maier, D.; Kendziorra, E.; Santangelo, A.

    2009-05-11

    The Simbol-X Low Energy Detector (LED), a 128x128 pixel DEPFET (Depleted Field Effect Transistor) array, will be read out at a very high rate (8000 frames/second) and, therefore, requires a very fast on board electronics. We present an FPGA-based LED camera electronics consisting of an Event Preprocessor (EPP) for on board data preprocessing and filtering of the Simbol-X low-energy detector and a related Sequencer (SEQ) to generate the necessary signals to control the readout.

  14. Investigation of fast nonstationary events with high-speed cinematography with a new drum camera

    NASA Astrophysics Data System (ADS)

    Eisfeld, Fritz

    1993-01-01

    For investigations of fast nonstationary events, e.g., flows, injection jets, etc., the high speed cinematography is particularly suitable, but there are difficulties with 3-dimensional motions. First the paper deals with problems and objectives which arose during the development of a new drum camera that is also suitable for high speed holography. The result is a drum camera for up to 200,000 f/s, also for use with holograms. The camera set-up and first test results are described, and possibilities of further developments are shown.

  15. A Fast Event Preprocessor and Sequencer for the Simbol-X Low Energy Detector

    NASA Astrophysics Data System (ADS)

    Schanz, T.; Tenzer, C.; Maier, D.; Kendziorra, E.; Santangelo, A.

    2009-05-01

    The Simbol-X Low Energy Detector (LED), a 128×128 pixel DEPFET (Depleted Field Effect Transistor) array, will be read out at a very high rate (8000 frames/second) and, therefore, requires a very fast on board electronics. We present an FPGA-based LED camera electronics consisting of an Event Preprocessor (EPP) for on board data preprocessing and filtering of the Simbol-X low-energy detector and a related Sequencer (SEQ) to generate the necessary signals to control the readout.

  16. Estimation of the radial force on the tokamak vessel wall during fast transient events

    SciTech Connect

    Pustovitov, V. D.

    2016-11-15

    The radial force balance in a tokamak during fast transient events with a duration much shorter than the resistive time of the vacuum vessel wall is analyzed. The aim of the work is to analytically estimate the resulting integral radial force on the wall. In contrast to the preceding study [Plasma Phys. Rep. 41, 952 (2015)], where a similar problem was considered for thermal quench, simultaneous changes in the profiles and values of the pressure and plasma current are allowed here. Thereby, the current quench and various methods of disruption mitigation used in the existing tokamaks and considered for future applications are also covered. General formulas for the force at an arbitrary sequence or combination of events are derived, and estimates for the standard tokamak model are made. The earlier results and conclusions are confirmed, and it is shown that, in the disruption mitigation scenarios accepted for ITER, the radial forces can be as high as in uncontrolled disruptions.

  17. Geological record of meltwater events at Qinghai Lake, China from the past 40 ka

    NASA Astrophysics Data System (ADS)

    Zhou, Weijian; Liu, Taibei; Wang, Hao; An, Zhisheng; Cheng, Peng; Zhu, Yizhi; Burr, G. S.

    2016-10-01

    We report here on a previously unpublished sediment core from Qinghai Lake, China, that preserves a continuous record of sedimentation for the past 40 ka. A striking feature of the record is a set of distinct meltwater events recorded at 35, 19 and 14 ka respectively. These events are manifest as distinct pulses of relatively old organic radiocarbon in the sediments. We interpret these as a signal of glacial melting in the Qinghai Lake watershed. The meltwater signals are closely correlated to temperature and precipitation records associated with deglaciation. The events at 19 ka and 14 ka correspond to well-established high latitude Melt Water Pulse (MWP) events during Marine Isotope Stage (MIS) 2, and the 35 ka event corresponds to a period of pervasive high lake levels in western China during late MIS 3. We interpret these anomalous dates as the result of relatively old carbon that was destabilized by the glaciers, and released into the lake as the glaciers melted. The data indicate that this process takes thousands of years. We expect that the approach employed here to identify these events is generally applicable to any lake system with a significant glacial meltwater component.

  18. Fast and accurate dating of nuclear events using La-140/Ba-140 isotopic activity ratio.

    PubMed

    Yamba, Kassoum; Sanogo, Oumar; Kalinowski, Martin B; Nikkinen, Mika; Koulidiati, Jean

    2016-06-01

    This study reports on a fast and accurate assessment of zero time of certain nuclear events using La-140/Ba-140 isotopic activity ratio. For a non-steady nuclear fission reaction, the dating is not possible. For the hypothesis of a nuclear explosion and for a release from a steady state nuclear fission reaction the zero-times will differ. This assessment is fast, because we propose some constants that can be used directly for the calculation of zero time and its upper and lower age limits. The assessment is accurate because of the calculation of zero time using a mathematical method, namely the weighted least-squares method, to evaluate an average value of the age of a nuclear event. This was done using two databases that exhibit differences between the values of some nuclear parameters. As an example, the calculation method is applied for the detection of radionuclides La-140 and Ba-140 in May 2010 at the radionuclides station JPP37 (Okinawa Island, Japan). Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Attributing Historical Changes in Probabilities of Record-Breaking Daily Temperature and Precipitation Extreme Events

    SciTech Connect

    Shiogama, Hideo; Imada, Yukiko; Mori, Masato; Mizuta, Ryo; Stone, Dáithí; Yoshida, Kohei; Arakawa, Osamu; Ikeda, Mikiko; Takahashi, Chiharu; Arai, Miki; Ishii, Masayoshi; Watanabe, Masahiro; Kimoto, Masahide

    2016-08-07

    Here, we describe two unprecedented large (100-member), longterm (61-year) ensembles based on MRI-AGCM3.2, which were driven by historical and non-warming climate forcing. These ensembles comprise the "Database for Policy Decision making for Future climate change (d4PDF)". We compare these ensembles to large ensembles based on another climate model, as well as to observed data, to investigate the influence of anthropogenic activities on historical changes in the numbers of record-breaking events, including: the annual coldest daily minimum temperature (TNn), the annual warmest daily maximum temperature (TXx) and the annual most intense daily precipitation event (Rx1day). These two climate model ensembles indicate that human activity has already had statistically significant impacts on the number of record-breaking extreme events worldwide mainly in the Northern Hemisphere land. Specifically, human activities have altered the likelihood that a wider area globally would suffer record-breaking TNn, TXx and Rx1day events than that observed over the 2001- 2010 period by a factor of at least 0.6, 5.4 and 1.3, respectively. However, we also find that the estimated spatial patterns and amplitudes of anthropogenic impacts on the probabilities of record-breaking events are sensitive to the climate model and/or natural-world boundary conditions used in the attribution studies.

  20. Attributing Historical Changes in Probabilities of Record-Breaking Daily Temperature and Precipitation Extreme Events

    DOE PAGES

    Shiogama, Hideo; Imada, Yukiko; Mori, Masato; ...

    2016-08-07

    Here, we describe two unprecedented large (100-member), longterm (61-year) ensembles based on MRI-AGCM3.2, which were driven by historical and non-warming climate forcing. These ensembles comprise the "Database for Policy Decision making for Future climate change (d4PDF)". We compare these ensembles to large ensembles based on another climate model, as well as to observed data, to investigate the influence of anthropogenic activities on historical changes in the numbers of record-breaking events, including: the annual coldest daily minimum temperature (TNn), the annual warmest daily maximum temperature (TXx) and the annual most intense daily precipitation event (Rx1day). These two climate model ensembles indicatemore » that human activity has already had statistically significant impacts on the number of record-breaking extreme events worldwide mainly in the Northern Hemisphere land. Specifically, human activities have altered the likelihood that a wider area globally would suffer record-breaking TNn, TXx and Rx1day events than that observed over the 2001- 2010 period by a factor of at least 0.6, 5.4 and 1.3, respectively. However, we also find that the estimated spatial patterns and amplitudes of anthropogenic impacts on the probabilities of record-breaking events are sensitive to the climate model and/or natural-world boundary conditions used in the attribution studies.« less

  1. Proxy records of Holocene storm events in coastal barrier systems: Storm-wave induced markers

    NASA Astrophysics Data System (ADS)

    Goslin, Jérôme; Clemmensen, Lars B.

    2017-10-01

    Extreme storm events in the coastal zone are one of the main forcing agents of short-term coastal system behavior. As such, storms represent a major threat to human activities concentrated along the coasts worldwide. In order to better understand the frequency of extreme events like storms, climate science must rely on longer-time records than the century-scale records of instrumental weather data. Proxy records of storm-wave or storm-wind induced activity in coastal barrier systems deposits have been widely used worldwide in recent years to document past storm events during the last millennia. This review provides a detailed state-of-the-art compilation of the proxies available from coastal barrier systems to reconstruct Holocene storm chronologies (paleotempestology). The present paper aims (I) to describe the erosional and depositional processes caused by storm-wave action in barrier and back-barrier systems (i.e. beach ridges, storm scarps and washover deposits), (ii) to understand how storm records can be extracted from barrier and back-barrier sedimentary bodies using stratigraphical, sedimentological, micro-paleontological and geochemical proxies and (iii) to show how to obtain chronological control on past storm events recorded in the sedimentary successions. The challenges that paleotempestology studies still face in the reconstruction of representative and reliable storm-chronologies using these various proxies are discussed, and future research prospects are outlined.

  2. A Compact Multiphoton 3D Imaging System for Recording Fast Neuronal Activity

    PubMed Central

    Vučinić, Dejan; Sejnowski, Terrence J.

    2007-01-01

    We constructed a simple and compact imaging system designed specifically for the recording of fast neuronal activity in a 3D volume. The system uses an Yb:KYW femtosecond laser we designed for use with acousto-optic deflection. An integrated two-axis acousto-optic deflector, driven by digitally synthesized signals, can target locations in three dimensions. Data acquisition and the control of scanning are performed by a LeCroy digital oscilloscope. The total cost of construction was one order of magnitude lower than that of a typical Ti:sapphire system. The entire imaging apparatus, including the laser, fits comfortably onto a small rig for electrophysiology. Despite the low cost and simplicity, the convergence of several new technologies allowed us to achieve the following capabilities: i) full-frame acquisition at video rates suitable for patch clamping; ii) random access in under ten microseconds with dwelling ability in the nominal focal plane; iii) three-dimensional random access with the ability to perform fast volume sweeps at kilohertz rates; and iv) fluorescence lifetime imaging. We demonstrate the ability to record action potentials with high temporal resolution using intracellularly loaded potentiometric dye di-2-ANEPEQ. Our design proffers easy integration with electrophysiology and promises a more widespread adoption of functional two-photon imaging as a tool for the study of neuronal activity. The software and firmware we developed is available for download at http://neurospy.org/ under an open source license. PMID:17684546

  3. A substitution method to improve completeness of events documentation in anesthesia records.

    PubMed

    Lamer, Antoine; De Jonckheere, Julien; Marcilly, Romaric; Tavernier, Benoît; Vallet, Benoît; Jeanne, Mathieu; Logier, Régis

    2015-12-01

    AIMS are optimized to find and display data and curves about one specific intervention but is not retrospective analysis on a huge volume of interventions. Such a system present two main limitation; (1) the transactional database architecture, (2) the completeness of documentation. In order to solve the architectural problem, data warehouses were developed to propose architecture suitable for analysis. However, completeness of documentation stays unsolved. In this paper, we describe a method which allows determining of substitution rules in order to detect missing anesthesia events in an anesthesia record. Our method is based on the principle that missing event could be detected using a substitution one defined as the nearest documented event. As an example, we focused on the automatic detection of the start and the end of anesthesia procedure when these events were not documented by the clinicians. We applied our method on a set of records in order to evaluate; (1) the event detection accuracy, (2) the improvement of valid records. For the year 2010-2012, we obtained event detection with a precision of 0.00 (-2.22; 2.00) min for the start of anesthesia and 0.10 (0.00; 0.35) min for the end of anesthesia. On the other hand, we increased by 21.1% the data completeness (from 80.3 to 97.2% of the total database) for the start and the end of anesthesia events. This method seems to be efficient to replace missing "start and end of anesthesia" events. This method could also be used to replace other missing time events in this particular data warehouse as well as in other kind of data warehouses.

  4. Motivation and intention to integrate physical activity into daily school life: the JAM World Record event.

    PubMed

    Vazou, Spyridoula; Vlachopoulos, Symeon P

    2014-11-01

    Research on the motivation of stakeholders to integrate physical activity into daily school life is limited. The purpose was to examine the motivation of stakeholders to participate in a world record physical activity event and whether motivation was associated with future intention to use activity breaks during the daily school life and future participation in a similar event. After the 2012 JAM (Just-a-Minute) World Record event, 686 adults (591 women; 76.1% participated for children <10 years) completed measures of motivational regulations and future intention to (a) use the activity breaks and (b) participate in the event. High intrinsic motivation and low extrinsic motivation and amotivation for participation in the next event were reported. Hierarchical regression analysis, controlling for age, gender, and occupation, showed that intrinsic forms of motivation positively predicted, whereas amotivation negatively predicted, future intention to participate in the event and use the activity breaks. Multivariate analyses of variance revealed that school-related participants were more intrinsically motivated and intended to use the activity breaks and repeat the event more than those who were not affiliated with a school. Nonschool participants reported higher extrinsic motivation and amotivation than school-related participants.

  5. An Analytical Approach for Estimating Fossil Record and Diversification Events in Sharks, Skates and Rays

    PubMed Central

    Guinot, Guillaume; Adnet, Sylvain; Cappetta, Henri

    2012-01-01

    Background Modern selachians and their supposed sister group (hybodont sharks) have a long and successful evolutionary history. Yet, although selachian remains are considered relatively common in the fossil record in comparison with other marine vertebrates, little is known about the quality of their fossil record. Similarly, only a few works based on specific time intervals have attempted to identify major events that marked the evolutionary history of this group. Methodology/Principal Findings Phylogenetic hypotheses concerning modern selachians’ interrelationships are numerous but differ significantly and no consensus has been found. The aim of the present study is to take advantage of the range of recent phylogenetic hypotheses in order to assess the fit of the selachian fossil record to phylogenies, according to two different branching methods. Compilation of these data allowed the inference of an estimated range of diversity through time and evolutionary events that marked this group over the past 300 Ma are identified. Results indicate that with the exception of high taxonomic ranks (orders), the selachian fossil record is by far imperfect, particularly for generic and post-Triassic data. Timing and amplitude of the various identified events that marked the selachian evolutionary history are discussed. Conclusion/Significance Some identified diversity events were mentioned in previous works using alternative methods (Early Jurassic, mid-Cretaceous, K/T boundary and late Paleogene diversity drops), thus reinforcing the efficiency of the methodology presented here in inferring evolutionary events. Other events (Permian/Triassic, Early and Late Cretaceous diversifications; Triassic/Jurassic extinction) are newly identified. Relationships between these events and paleoenvironmental characteristics and other groups’ evolutionary history are proposed. PMID:22957091

  6. Continuous methane record of abrupt climate change 10-68 ka: sighting Heinrich events in the ice core record

    NASA Astrophysics Data System (ADS)

    Rhodes, Rachael; Brook, Edward; Chiang, John; Blunier, Thomas; Cheng, Hai; Edwards, R. Lawrence; Maselli, Olivia; McConnell, Joseph; Romanini, Daniele; Severinghaus, Jeffrey; Sowers, Todd; Stowasser, Christopher

    2014-05-01

    The Last Glacial period was punctuated by millennial scale abrupt climate changes - Dansgaard-Oeschger (D-O) cycles and Heinrich events. Controls on the magnitude and frequency of these climate perturbations, and how they may be inter-related, remain unclear. Specific problems include the difficulty of dating Heinrich sediment layers and local bias of key paleoclimate archives. We present a highly detailed and precise record of ice core methane (CH4), a globally integrated signal, which resolves climatic features in unprecedented resolution. Abrupt CH4 increases are resolved in Heinrich Stadials (HS) 1, 2, 4 and 5 where, in contrast to all D-O cycles, there are no concurrent abrupt changes in Greenland temperature. Using modern-day tropical rainfall variability as an analog, we propose that strong cooling in the North Atlantic severely restricted the northerly range of the Intertropical Convergence Zone (ITCZ), leading to an enhanced wet season over Southern Hemisphere tropical land areas, and consequently driving production of excess CH4 in tropical wetlands. Our findings place four Heinrich events firmly within ice core chronologies and suggest maximum durations of 778 to 1606 yr. CH4 anomalies are only associated with Heinrich events of Hudson Strait provenance, indicating that the tropical impacts of Heinrich events were not uniform.

  7. Large solar flares - Analysis of the events recorded by the Mont Blanc neutrino detector

    NASA Astrophysics Data System (ADS)

    Aglietta, M.; Badino, G.; Bologna, G.; Castagnoli, C.; Castellina, A.; Dadykin, V. L.; Fulgione, W.; Galeotti, P.; Kalchukov, F. F.; Korolkova, I. V.; Kortchaguin, P. V.; Kudryavtsev, V. A.; Malguin, A. S.; Periale, L.; Ryassny, V. G.; Ryazhskaya, O. G.; Saavedra, O.; Trinchero, G.; Vernetto, S.; Yakushev, V. F.; Zatsepin, G. T.

    1991-11-01

    Analytical results are discussed from events recorded by the Mont Blanc neutrino detector during 19 large solar flares from August 1988 to March 1990, including the powerful flares of September 29 and October 19, 1989. It is found that no significant neutrino signal coincides temporally with solar flares. Upper limits are obtained for the integral neutrino and antineutrino flux of different flavors.

  8. 77 FR 74144 - Federal Motor Vehicle Safety Standards; Event Data Recorders

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-13

    ...In August 2006, NHTSA established a regulation that sets forth requirements for data elements, data capture and format, data retrieval, and data crash survivability for event data recorders (EDRs) installed in light vehicles. The requirements apply to light vehicles that are manufactured on or after September 1, 2012, and are equipped with EDRs. However, the regulation does not mandate the......

  9. Fast, deep record length, time-resolved visible spectroscopy of plasmas using fiber grids

    NASA Astrophysics Data System (ADS)

    Brockington, Samuel; Case, Andrew; Cruz, Edward; Witherspoon, F. Douglas; Horton, Robert; Klauser, Ruth; Hwang, D. Q.

    2016-10-01

    HyperV Technologies is developing a fiber-coupled, deep-record-length, low-light camera head for performing high time resolution spectroscopy on visible emission from plasma events. New solid-state Silicon Photo-Multiplier (SiPM) chips are capable of single photon event detection and high speed data acquisition. By coupling the output of a spectrometer to an imaging fiber bundle connected to a bank of amplified SiPMs, time-resolved spectroscopic imagers of 100 to 1,000 pixels can be constructed. Target pixel performance is 10 Megaframes/sec with record lengths of up to 256,000 frames yielding 25.6 milliseconds of record at10 Megasamples/sec resolution. Pixel resolutions of 8 to 12 bits are pos- sible. Pixel pitch can be refined by using grids of 100 μm to 1000 μm diameter fibers. A prototype 32-pixel spectroscopic imager employing this technique was constructed and successfully tested at the University of California at Davis Compact Toroid Injection Experiment (CTIX) as a full demonstration of the concept. Experimental results will be dis-cussed, along with future plans for the Phase 2 project, and potential applications to plasma experiments . Work supported by USDOE SBIR Grant DE-SC0013801.

  10. Adding video recording increases the diagnostic yield of routine electroencephalograms in children with frequent paroxysmal events.

    PubMed

    Watemberg, Nathan; Tziperman, Barak; Dabby, Ron; Hasan, Mariana; Zehavi, Liora; Lerman-Sagie, Tally

    2005-05-01

    To report on the usefulness of adding video recording to routine EEG studies of infants and children with frequent paroxysmal events. We analyzed the efficacy of this diagnostic means during a 4-year period. The decision whether to add video recording was made by the pediatric EEG interpreter at the time of the study. Studies were planned to last between 20 and 30 min, and, if needed, were extended by the EEG interpreter. For most studies, video recording was added from the beginning of EEG recording. In a minority of cases, the addition of video was implemented during the first part of the EEG test, as clinical events became obvious. In these cases, a new study (file) was begun. The success rate was analyzed according to the indications for the EEG study: paroxysmal eye movements, tremor, suspected seizures, myoclonus, staring episodes, suspected stereotypias and tics, absence epilepsy follow-up, cyanotic episodes, and suspected psychogenic nonepileptic events. Video recording was added to 137 of 666 routine studies. Mean patient age was 4.8 years. The nature of the event was determined in 61 (45%) of the EEG studies. Twenty-eight percent were hospitalized patients. The average study duration was 26 min. This diagnostic means was particularly useful for paroxysmal eye movements, staring spells, myoclonic jerks, stereotypias, and psychogenic nonepileptic events. About 46% of 116 patients for whom cognitive data were available were mentally retarded. EEG with added video recording was successfully performed in all 116 cases and provided useful information in 29 (55%) of these 53 patients. Adding video recording to routine EEG was helpful in 45% of cases referred for frequent paroxysmal events. This technique proved useful for hospitalized children as well as for outpatients. Moreover, it was successfully applied in cognitively impaired patients. Infants and children with paroxysmal eye movements, staring spells, myoclonic jerks, stereotypias, and pseudoseizures

  11. Incidence and types of preventable adverse events in elderly patients: population based review of medical records

    PubMed Central

    Thomas, Eric J; Brennan, Troyen A

    2000-01-01

    Objective To determine the incidence and types of preventable adverse events in elderly patients. Design Review of random sample of medical records in two stage process by nurses and physicians to detect adverse events. Two study investigators then judged preventability. Setting Hospitals in US states of Utah and Colorado, excluding psychiatric and Veterans Administration hospitals. Subjects 15 000 hospitalised patients discharged in 1992. Main outcome measures Incidence of preventable adverse events (number of preventable events per 100 discharges) in elderly patients (⩾65 years old) and non-elderly patients (16-64 years). Results When results were extrapolated to represent all discharges in 1992 in both states, non-elderly patients had 8901 adverse events (incidence 2.80% (SE 0.18%)) compared with 7419 (5.29% (0.37%)) among elderly patients (P=0.001). Non-elderly patients had 5038 preventable adverse events (incidence 1.58% (0.14%)) compared with 4134 (2.95% (0.28%)) in elderly patients (P=0.001). Elderly patients had a higher incidence of preventable events related to medical procedures (such as thoracentesis, cardiac catheterisation) (0.69% (0.14%) v 0.13% (0.04%)), preventable adverse drug events (0.63% (0.14%) v 0.17% (0.05%)), and preventable falls (0.10% (0.06%) v 0.01% (0.02%)). In multivariate analyses, adjusted for comorbid illnesses and case mix, age was not an independent predictor of preventable adverse events. Conclusions Preventable adverse events were more common among elderly patients, probably because of the clinical complexity of their care rather than age based discrimination. Preventable adverse drug events, events related to medical procedures, and falls were especially common in elderly patients and should be targets for efforts to prevent errors. PMID:10720355

  12. Plant microfossil record of the terminal Cretaceous event in the western United States and Canada

    NASA Technical Reports Server (NTRS)

    Nichols, D. J.; Fleming, R. F.

    1988-01-01

    Plant microfossils, principally pollen grains and spores produced by land plants, provide an excellent record of the terminal Cretaceous event in nonmarine environments. The record indicates regional devastation of the latest Cretaceous vegetation with the extinction of many groups, followed by a recolonization of the earliest Tertiary land surface, and development of a permanently changed land flora. The regional variations in depositional environments, plant communities, and paleoclimates provide insight into the nature and effects of the event, which were short-lived but profound. The plant microfossil data support the hypothesis that an abruptly initiated, major ecological crisis occurred at the end of the Cretaceous. Disruption of the Late Cretaceous flora ultimately contributred to the rise of modern vegetation. The plant microfossils together with geochemical and mineralogical data are consistent with an extraterrestrial impact having been the cause of the terminal Cretaceous event.

  13. Enabling Near Real-Time Remote Search for Fast Transient Events with Lossy Data Compression

    NASA Astrophysics Data System (ADS)

    Vohl, Dany; Pritchard, Tyler; Andreoni, Igor; Cooke, Jeffrey; Meade, Bernard

    2017-09-01

    We present a systematic evaluation of JPEG2000 (ISO/IEC 15444) as a transport data format to enable rapid remote searches for fast transient events as part of the Deeper Wider Faster programme. Deeper Wider Faster programme uses 20 telescopes from radio to gamma rays to perform simultaneous and rapid-response follow-up searches for fast transient events on millisecond-to-hours timescales. Deeper Wider Faster programme search demands have a set of constraints that is becoming common amongst large collaborations. Here, we focus on the rapid optical data component of Deeper Wider Faster programme led by the Dark Energy Camera at Cerro Tololo Inter-American Observatory. Each Dark Energy Camera image has 70 total coupled-charged devices saved as a 1.2 gigabyte FITS file. Near real-time data processing and fast transient candidate identifications-in minutes for rapid follow-up triggers on other telescopes-requires computational power exceeding what is currently available on-site at Cerro Tololo Inter-American Observatory. In this context, data files need to be transmitted rapidly to a foreign location for supercomputing post-processing, source finding, visualisation and analysis. This step in the search process poses a major bottleneck, and reducing the data size helps accommodate faster data transmission. To maximise our gain in transfer time and still achieve our science goals, we opt for lossy data compression-keeping in mind that raw data is archived and can be evaluated at a later time. We evaluate how lossy JPEG2000 compression affects the process of finding transients, and find only a negligible effect for compression ratios up to 25:1. We also find a linear relation between compression ratio and the mean estimated data transmission speed-up factor. Adding highly customised compression and decompression steps to the science pipeline considerably reduces the transmission time-validating its introduction to the Deeper Wider Faster programme science pipeline and

  14. A scheme for recording a fast process at nanosecond scale by using digital holographic interferometry with continuous wave laser

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Zhao, Jianlin; Di, Jianglei; Jiang, Biqiang

    2015-04-01

    A scheme for recording fast process at nanosecond scale by using digital holographic interferometry with continuous wave (CW) laser is described and demonstrated experimentally, which employs delayed-time fibers and angular multiplexing technique and can realize the variable temporal resolution at nanosecond scale and different measured depths of object field at certain temporal resolution. The actual delay-time is controlled by two delayed-time fibers with different lengths. The object field information in two different states can be simultaneously recorded in a composite hologram. This scheme is also suitable for recording fast process at picosecond scale, by using an electro-optic modulator.

  15. Fast Variable Structure Stochastic Automaton for Discovering and Tracking Spatiotemporal Event Patterns.

    PubMed

    Zhang, Junqi; Wang, Yuheng; Wang, Cheng; Zhou, MengChu

    2017-04-05

    Discovering and tracking spatiotemporal event patterns have many applications. For example, in a smart-home project, a set of spatiotemporal pattern learning automata are used to monitor a user's repetitive activities, by which the home's automaticity can be promoted while some of his/her burdens can be reduced. Existing algorithms for spatiotemporal event pattern recognition in dynamic noisy environment are based on fixed structure stochastic automata whose state transition function is fixed and predesigned to guarantee their immunity to noise. However, such design is conservative because it needs continuous and identical feedbacks to converge, thus leading to its very low convergence rate. In many real-life applications, such as ambient assisted living, consecutive nonoccurrences of an elder resident's routine activities should be treated with an alert as quickly as possible. On the other hand, no alert should be output even for some occurrences in order to diminish the effects caused by noise. Clearly, confronting a pattern's change, slow speed and low accuracy may degrade a user's life security. This paper proposes a fast and accurate leaning automaton based on variable structure stochastic automata to satisfy the realistic requirements for both speed and accuracy. Bias toward alert is necessary for elder residents while the existing method can only support the bias toward ``no alert.'' This paper introduces a method to allow bias toward alert or no alert to meet a user's specific bias requirement. Experimental results show its better performance than the state-of-the-art methods.

  16. Geochemical Records of Bleaching Events and the Associated Stressors From the Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Roark, E. B.; McCulloch, M.; Ingram, B. L.; Marshall, J. F.

    2003-12-01

    The health of coral reefs world-wide is increasingly threatened by a wide array of stressors. On the Great Barrier Reef (GBR) these stressors include increased sediment flux associated with land use changes, increased sea surface temperatures (SST) and salinity changes due to large floods, the latter two of which are factors in an increased number of bleaching events. The ability to document long-term change in these stressors along with changes in the number of bleaching events would help discern what are natural and anthropogenic changes in this ecosystem. Here we present results of an initial calibration effort aimed at identifying bleaching events and the associated stressors using stable isotopic and trace element analysis in coral cores. Three ˜15-year time series of geochemical measurements (δ 13C, δ 18O, and Sr/Ca) on Porites coral cores obtained from Pandora Reef and the Keppel Islands on the GBR have been developed at near weekly resolution. Since the δ 13C of the coral skeletal carbonate is known to be affected by both environmental factors (e.g. insolation and temperature) and physiological factors (e.g. photosynthesis, calcification, and the statues of the symbiotic relationship between corals and zooxanthellae) it is the most promising proxy for reconstructing past bleaching events. The first record (PAN-98) comes from a coral head that had undergone bleaching and died shortly after the large-scale bleaching events on Pandora Reef in 1998. A second core (PAN-02) was collected from a living coral within 10m of PAN-98 in 2002. Sr/Ca ratios in both cores tracked even the smallest details of an in situ SST record. The increase in SST that occurred three to four weeks prior to bleaching was faithfully recorded by a similar decrease in the Sr/Ca ratio in PAN-98, indicating that calcification continued despite the high SST of 30-31° C. The δ 13C values decreased by about 5‰ , one week after the SST increase, and remained at this value for about 4

  17. A New Characteristic Function for Fast Time-Reverse Seismic Event Location

    NASA Astrophysics Data System (ADS)

    Hendriyana, Andri; Bauer, Klaus; Weber, Michael; Jaya, Makky; Muksin, Muksin

    2015-04-01

    Microseismicity produced by natural activities is usually characterized by low signal-to-noise ratio and huge amount of data as recording is conducted for a long period of time. Locating microseismic events is preferably carried out using migration-based methods such as time-reverse modeling (TRM). The original TRM is based on backpropagating the wavefield from the receiver down to the source location. Alternatively, we are using a characteristic function (CF) derived from the measured wavefield as input for the TRM. The motivation for such a strategy is to avoid undesired contributions from secondary arrivals which may generate artifacts in the final images. In this presentation, we introduce a new CF as input for TRM method. To obtain this CF, initially we apply kurtosis-based automatic onset detection and convolution with a given wavelet. The convolution with low frequency wavelets allows us to conduct time-reverse modeling using coarser sampling hence it will reduce computing time. We apply the method to locate seismic events measured along an active part of the Sumatra Fault around the Tarutung pull-apart basin (North Sumatra, Indonesia). The results show that seismic events are well-determined since they are concentrated along the Sumatran fault. Internal details of the Tarutung basin structure could be derived. Our results are consistent with those obtained from inversion of manually picked travel time data.

  18. Changes in record-breaking temperature events in China and projections for the future

    NASA Astrophysics Data System (ADS)

    Deng, Hanqing; Liu, Chun; Lu, Yanyu; He, Dongyan; Tian, Hong

    2017-06-01

    As global warming intensifies, more record-breaking (RB) temperature events are reported in many places around the world where temperatures are higher than ever before http://cn.bing.com/dict/search?q=.&FORM=BDVSP6&mkt=zh-cn. The RB temperatures have caused severe impacts on ecosystems and human society. Here, we address changes in RB temperature events occurring over China in the past (1961-2014) as well as future projections (2006-2100) using observational data and the newly available simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5). The number of RB events has a significant multi-decadal variability in China, and the intensity expresses a strong decrease from 1961 to 2014. However, more frequent RB events occurred in mid-eastern and northeastern China over last 30 years (1981-2010). Comparisons with observational data indicate multi-model ensemble (MME) simulations from the CMIP5 model perform well in simulating RB events for the historical run period (1961-2005). CMIP5 MME shows a relatively larger uncertainty for the change in intensity. From 2051 to 2100, fewer RB events are projected to occur in most parts of China according to RCP 2.6 scenarios. Over the longer period from 2006 to 2100, a remarkable increase is expected for the entire country according to RCP 8.5 scenarios and the maximum numbers of RB events increase by approximately 600 per year at end of twenty-first century.

  19. A novel method for inferring RFID tag reader recordings into clinical events.

    PubMed

    Chang, Yung-Ting; Syed-Abdul, Shabbir; Tsai, Chung-You; Li, Yu-Chuan

    2011-12-01

    Nosocomial infections (NIs) are among the important indicators used for evaluating patients' safety and hospital performance during accreditation of hospitals. NI rate is higher in Intensive Care Units (ICUs) than in the general wards because patients require intense care involving both invasive and non-invasive clinical procedures. The emergence of Superbugs is motivating health providers to enhance infection control measures. Contact behavior between health caregivers and patients is one of the main causes of cross infections. In this technology driven era remote monitoring of patients and caregivers in the hospital setting can be performed reliably, and thus is in demand. Proximity sensing using radio frequency identification (RFID) technology can be helpful in capturing and keeping track on all contact history between health caregivers and patients for example. This study intended to extend the use of proximity sensing of radio frequency identification technology by proposing a model for inferring RFID tag reader recordings into clinical events. The aims of the study are twofold. The first aim is to set up a Contact History Inferential Model (CHIM) between health caregivers and patients. The second is to verify CHIM with real-time observation done at the ICU ward. A pre-study was conducted followed by two study phases. During the pre-study proximity sensing of RFID was tested, and deployment of the RFID in the Clinical Skill Center in one of the medical centers in Taiwan was done. We simulated clinical events and developed CHIM using variables such as duration of time, frequency, and identity (tag) numbers assigned to caregivers. All clinical proximity events are classified into close-in events, contact events and invasive events. During the first phase three observers were recruited to do real time recordings of all clinical events in the Clinical Skill Center with the deployed automated RFID interaction recording system. The observations were used to verify

  20. Fast Model Adaptation for Automated Section Classification in Electronic Medical Records.

    PubMed

    Ni, Jian; Delaney, Brian; Florian, Radu

    2015-01-01

    Medical information extraction is the automatic extraction of structured information from electronic medical records, where such information can be used for improving healthcare processes and medical decision making. In this paper, we study one important medical information extraction task called section classification. The objective of section classification is to automatically identify sections in a medical document and classify them into one of the pre-defined section types. Training section classification models typically requires large amounts of human labeled training data to achieve high accuracy. Annotating institution-specific data, however, can be both expensive and time-consuming; which poses a big hurdle for adapting a section classification model to new medical institutions. In this paper, we apply two advanced machine learning techniques, active learning and distant supervision, to reduce annotation cost and achieve fast model adaptation for automated section classification in electronic medical records. Our experiment results show that active learning reduces the annotation cost and time by more than 50%, and distant supervision can achieve good model accuracy using weakly labeled training data only.

  1. Contrasting sulfur isotope records during the Late Devonian punctata and Upper Kellwasser events

    NASA Astrophysics Data System (ADS)

    Sim, M.; Ono, S.; Hurtgen, M. T.

    2013-12-01

    The Late Devonian was a period of intense biological and environmental changes, including terrestrial afforestation, a series of asteroid impacts, and active orogeny due to the accretion of continental blocks. High amplitude positive carbon isotope excursions, the punctata and Kellwasser events, reflect major perturbations in the global carbon cycle during this period, which have been attributed to increased continental weathering and subsequent ocean eutrophication. Despite the comparable carbon isotope anomalies, however, a global biological crisis has been reported only for the Kellwasser events, while very low extinction intensity characterizes the punctata Event. We will present sulfur isotope records of carbonate associated sulfate (CAS) and pyrite from Frasnian-Famennian sections in the Great Basin, USA, and evaluate the role of sulfur during the punctata and Upper Kellwasser events. A positive sulfur isotope shift in both CAS and pyrite accompanies the onset of the punctata Event, but with a larger extent in the latter. As a result, the sulfur isotope offset between CAS and pyrite (Δ34SCAS-py) plummeted to less than 10‰. In the middle of the punctata Event, a sharp negative δ34SCAS excursion occurred just after the Alamo Impact, leading to the negative Δ34SCAS-py values. Unlike the rapid oscillations of δ34Spy and δ34SCAS during the punctata Event, the Upper Kellwasser was a period of stability, except for a brief drop of δ34SCAS before the event. Paired sulfur isotope data, aided by a simple box model, suggests that geochemical cycle of sulfur might be responsible for the contrasting biological responses to these two events. Superheavy pyrite and high stratigraphic variability of δ34Spy and δ34SCAS demonstrate a relatively small oceanic sulfate pool during the punctata Event, and the Alamo Impact likely triggered to the rapid oxidation of microbially-produced sulfide. The expansion of sulfidic bottom water thus may have been impeded, thereby

  2. Implementing Dense Arrays of Single-Channel Seismic Recorders to Detect Global Teleseism Events

    NASA Astrophysics Data System (ADS)

    O'Rourke, C. T.; Sheehan, A. F.; Yang, Z.; Harder, S. H.; Miller, K. C.; Worthington, L. L.

    2010-12-01

    Single-Channel Reftek RT125A (Texan) seismic recorders have frequently been used to detect active-source seismic events (blasts). However, they have been thought to be inefficient for recording global seismicity over long time scales because of short battery life (days), single-channel capability, and typically high frequency response of associated geophones. The goal of this research is to determine just how effective Texan recorders can be for passive teleseism detection. An array of >800 Reftek RT125A recorders and geophones (OYO Geospace 4.5Hz) was recently deployed across the Bighorn Mountain Range in northern Wyoming as part of the EarthScope Bighorn Arch Seismic Experiment (BASE) Flexible Array experiment. In addition, 38 broadband and 172 short-period 3-component seismic stations were interspersed in the array, which we hope will aid in the detection of S wave arrival. Each RT125A was swapped every 4 days to replace batteries and offload data, allowing for a continuous data record over 15 days and potentially recording several global events per day. Because the array is densely spaced (~1km) we expect to be able to image the subsurface with a higher precision than was possible with wider arrays. Preliminary results have shown that M~5.0 events were discernable up to 8,000 km distance, and several M>6.0 were observable from any distance. For example the P, PP and S waves from a magnitude 6.4 earthquake in the Aleutian Islands, AK (12:58GMT Aug 4 2010, depth 27km) can be seen clearly across the entire array. Despite the fact that the geophones are 4.5 Hz instruments, quality signals up to 3 s are observed for teleseisms with no special processing. Regional and local events are also well recorded, including a magnitude 4.8 earthquake near Jackson Hole, Wyoming, associated aftershocks of the Jackson Hole earthquake, and over 200 local mine blasts. The mine blasts were large enough to be recorded by the USArray Array Network Facility (ANF), requiring usable

  3. A fast, robust algorithm for power line interference cancellation in neural recording

    NASA Astrophysics Data System (ADS)

    Keshtkaran, Mohammad Reza; Yang, Zhi

    2014-04-01

    Objective. Power line interference may severely corrupt neural recordings at 50/60 Hz and harmonic frequencies. The interference is usually non-stationary and can vary in frequency, amplitude and phase. To retrieve the gamma-band oscillations at the contaminated frequencies, it is desired to remove the interference without compromising the actual neural signals at the interference frequency bands. In this paper, we present a robust and computationally efficient algorithm for removing power line interference from neural recordings. Approach. The algorithm includes four steps. First, an adaptive notch filter is used to estimate the fundamental frequency of the interference. Subsequently, based on the estimated frequency, harmonics are generated by using discrete-time oscillators, and then the amplitude and phase of each harmonic are estimated by using a modified recursive least squares algorithm. Finally, the estimated interference is subtracted from the recorded data. Main results. The algorithm does not require any reference signal, and can track the frequency, phase and amplitude of each harmonic. When benchmarked with other popular approaches, our algorithm performs better in terms of noise immunity, convergence speed and output signal-to-noise ratio (SNR). While minimally affecting the signal bands of interest, the algorithm consistently yields fast convergence (<100 ms) and substantial interference rejection (output SNR >30 dB) in different conditions of interference strengths (input SNR from -30 to 30 dB), power line frequencies (45-65 Hz) and phase and amplitude drifts. In addition, the algorithm features a straightforward parameter adjustment since the parameters are independent of the input SNR, input signal power and the sampling rate. A hardware prototype was fabricated in a 65 nm CMOS process and tested. Software implementation of the algorithm has been made available for open access at https://github.com/mrezak/removePLI. Significance. The proposed

  4. New records with examples of potential host colonization events for hypopi (Acari: Hypoderatidae) from birds

    USGS Publications Warehouse

    Pence, Danny B.; Spalding, M.G.; Bergan, J.F.; Cole, R.A.

    1997-01-01

    New host, geographic records, or both are established for 14 species of hypoderatid deutonymphs from 14 species of birds in North America. Ten of these records are regarded as examples of a potential host colonization event where these hypopi have become established in hosts other than those with which they are normally associated. Herein, potential host colonization events by hypoderatid deutonymphs are regarded as more of an ecologically determined than physiologically specific phenomenon, often specifically related to sharing of nesting sites in the same rookeries by different host taxa. Neottialges ibisicola Young & Pence is placed as a junior synonym of Neottialges plegadicola Fain. The taxonomic status of Hypodectes propus from columbid versus ardeid hosts needs further study.

  5. Intrathoracic impedance vs daily weight monitoring for predicting worsening heart failure events: results of the Fluid Accumulation Status Trial (FAST).

    PubMed

    Abraham, William T; Compton, Steven; Haas, Garrie; Foreman, Blair; Canby, Robert C; Fishel, Robert; McRae, Scott; Toledo, Gloria B; Sarkar, Shantanu; Hettrick, Douglas A

    2011-01-01

    The relative sensitivity and unexplained detection rate of changes in intrathoracic impedance has not been compared with standard heart failure (HF) monitoring using daily weight changes. The Fluid Accumulation Status Trial (FAST) prospectively followed 156 HF patients with implanted cardioverter-defibrillator or cardiac resynchronization therapy defibrillator devices modified to record daily changes in intrathoracic impedance in a blinded fashion for 537±312 days. Daily impedance changes were used to calculate a fluid index that could be compared with a prespecified threshold. True positives were defined as adjudicated episodes of worsening HF occurring within 30 days of a fluid index above threshold or an acute weight gain. Unexplained detections were defined as threshold crossings or acute weight gains not associated with worsening HF. Impedance measurements were performed on >99% of follow-up days, compared with only 76% of days for weight measurements. Sixty-five HF events occurred during follow-up (0.32/patient-year). Forty HF events were detected by impedance but not weight, whereas 5 were detected by weight but not impedance. Sensitivity was greater (76% vs 23%; P<.0001) and unexplained detection rate was lower (1.9 vs 4.3/patient-year; P<.0001) for intrathoracic impedance monitoring at the threshold of 60Ω days compared with acute weight increases of 3 lbs in 1 day or 5 lbs in 3 days and also over a wide range of fluid index and weight thresholds. The sensitivity and unexplained detection rate of intrathoracic impedance monitoring was superior to that seen for acute weight changes. Intrathoracic impedance monitoring represents a useful adjunctive clinical tool for managing HF in patients with implanted devices.

  6. A fast and robust method for moment tensor and depth determination of shallow seismic events in CTBT related studies.

    NASA Astrophysics Data System (ADS)

    Baker, Ben; Stachnik, Joshua; Rozhkov, Mikhail

    2017-04-01

    International Data Center is required to conduct expert technical analysis and special studies to improve event parameters and assist State Parties in identifying the source of specific event according to the protocol to the Protocol to the Comprehensive Nuclear Test Ban Treaty. Determination of seismic event source mechanism and its depth is closely related to these tasks. It is typically done through a strategic linearized inversion of the waveforms for a complete or subset of source parameters, or similarly defined grid search through precomputed Greens Functions created for particular source models. In this presentation we demonstrate preliminary results obtained with the latter approach from an improved software design. In this development we tried to be compliant with different modes of CTBT monitoring regime and cover wide range of source-receiver distances (regional to teleseismic), resolve shallow source depths, provide full moment tensor solution based on body and surface waves recordings, be fast to satisfy both on-demand studies and automatic processing and properly incorporate observed waveforms and any uncertainties a priori as well as accurately estimate posteriori uncertainties. Posterior distributions of moment tensor parameters show narrow peaks where a significant number of reliable surface wave observations are available. For earthquake examples, fault orientation (strike, dip, and rake) posterior distributions also provide results consistent with published catalogues. Inclusion of observations on horizontal components will provide further constraints. In addition, the calculation of teleseismic P wave Green's Functions are improved through prior analysis to determine an appropriate attenuation parameter for each source-receiver path. Implemented HDF5 based Green's Functions pre-packaging allows much greater flexibility in utilizing different software packages and methods for computation. Further additions will have the rapid use of Instaseis

  7. Impulsive event probability in the radiocarbon record in VIII - XI centuries

    NASA Astrophysics Data System (ADS)

    Kovylova, E. G.; Konstantinov, A. N.

    2015-12-01

    The abundance of cosmogenic isotopes in natural samples is the main source of information about past variations of cosmic ray intensity, in the solar activity and in the strength of the geomagnetic field. Sharp increases could originate from powerful impulsive events such as solar flares, gamma-rays from supernova explosions and gamma-ray bursts. A significant increase in the radiocarbon record has been detected recently in tree rings around AD 775 [1]. Both large solar proton event (SPE) [2] and gamma-ray burst (GRB) in our Galaxy [3] are favored as a source. However, either of the explanations faces difficulties of low event rate because of detection of a similar peak around AD993 [4], [5]. What is more, we know other similar result [6]. We carried out a statistical analysis of these three data sets. It is shown that AD 775 event differs fundamentally from AD 993 and AD 1006 events, because the last two can be explained without the assumption of the impulsive event.

  8. Using Temporal Patterns in Medical Records to Discern Adverse Drug Events from Indications

    PubMed Central

    Liu, Yi; LePendu, Paea; Iyer, Srinivasan; Shah, Nigam H.

    2012-01-01

    Researchers estimate that electronic health record systems record roughly 2-million ambulatory adverse drug events and that patients suffer from adverse drug events in roughly 30% of hospital stays. Some have used structured databases of patient medical records and health insurance claims recently—going beyond the current paradigm of using spontaneous reporting systems like AERS—to detect drug-safety signals. However, most efforts do not use the free-text from clinical notes in monitoring for drug-safety signals. We hypothesize that drug–disease co-occurrences, extracted from ontology-based annotations of the clinical notes, can be examined for statistical enrichment and used for drug safety surveillance. When analyzing such co-occurrences of drugs and diseases, one major challenge is to differentiate whether the disease in a drug–disease pair represents an indication or an adverse event. We demonstrate that it is possible to make this distinction by combining the frequency distribution of the drug, the disease, and the drug-disease pair as well as the temporal ordering of the drugs and diseases in each pair across more than one million patients. PMID:22779050

  9. Cosmic ray event in 994 C.E. recorded in radiocarbon from Danish oak

    NASA Astrophysics Data System (ADS)

    Fogtmann-Schulz, A.; Østbø, S. M.; Nielsen, S. G. B.; Olsen, J.; Karoff, C.; Knudsen, M. F.

    2017-08-01

    We present measurements of radiocarbon in annual tree rings from the time period 980-1006 Common Era (C.E.), hereby covering the cosmic ray event in 994 C.E. The new radiocarbon record from Danish oak is based on both earlywood and latewood fractions of the tree rings, which makes it possible to study seasonal variations in 14C production. The measurements show a rapid increase of ˜10‰ from 993 to 994 C.E. in latewood, followed by a modest decline and relatively high values over the ensuing ˜10 years. This rapid increase occurs from 994 to 995 C.E. in earlywood, suggesting that the cosmic ray event most likely occurred during the period between April and June 994 C.E. Our new record from Danish oak shows strong agreement with existing Δ14C records from Japan, thus supporting the hypothesis that the 994 C.E. cosmic ray event was uniform throughout the Northern Hemisphere and therefore can be used as an astrochronological tie point to anchor floating chronologies of ancient history.

  10. An algorithm to detect low incidence arrhythmic events in electrocardiographic records from ambulatory patients.

    PubMed

    Hungenahally, S K; Willis, R J

    1994-11-01

    An algorithm was devised to detect low incidence arrhythmic events in electrocardiograms obtained during ambulatory monitoring. The algorithm incorporated baseline correction and R wave detection. The RR interval was used to identify tachycardia, bradycardia, and premature ventricular beats. Only a few beats before and after the arrhythmic event were stored. The software was evaluated on a prototype hardware system which consisted of an Intel 86/30 single board computer with a suitable analog pre-processor and an analog to digital converter. The algorithm was used to determine the incidence and type of arrhythmia in records from an ambulatory electrocardiogram (ECG) database and from a cardiac exercise laboratory. These results were compared to annotations on the records which were assumed to be correct. Standard criteria used previously to evaluate algorithms designed for arrhythmia detection were sensitivity, specificity, and diagnostic accuracy. Sensitivities ranging from 77 to 100%, specificities from 94 to 100%, and diagnostic accuracies from 92 to 100% were obtained on the different data sets. These results compare favourably with published results based on more elaborate algorithms. By circumventing the need to make a continuous record of the ECG, the algorithm could form the basis for a compact monitoring device for the detection of arrhythmic events which are so infrequent that standard 24-h Holter monitoring is insufficient.

  11. Abrupt Climate Events Recorded in Chinese and Central Asian Loess Sequences

    NASA Astrophysics Data System (ADS)

    Machalett, Bjoern; Oches, Eric A.; Haam, Eddie; Lai, Zhongping; Endlicher, Wilfried

    2013-04-01

    Past climate dynamics associated with the Eurasian continent have been extensively studied. However, the impact of intra-hemispheric-scale climate variability on the entire Eurasian landmass, as well as the self-generated effects of the continent on the global climate system, is still a matter of investigation . While western Atlantic polar and tropical air masses penetrate into the continent and are transformed as they cross Eurasia, the interior regions of Eurasia strongly influence Earth's climate system. Significant cooling and heating of Central and High Asia drive interactions between atmospheric and oceanic processes and regulate teleconnection patterns across the Northern Hemisphere. This paper utilizes high resolution particle size data from the Central Asian loess sequence at Remisowka, Kazakhstan, and the long studied, monsoon-influenced Chinese loess sequence at Xifeng, to reconstruct past atmospheric circulation and aeolian dust dynamics within interior Eurasia since the last interglacial period. The observed dynamics in aeolian dust transport closely mirror d18O and fine dust variations measured in Greenland ice cores, suggesting a correlation with short-term climate oscillations (DO events) recorded therein. An Asian origin of fine aeolian dust preserved in Greenland ice cores has been discussed previously, and recent papers reveal a close link between Asian aeolian dust dynamics and DO events recorded in Greenland ice cores. In this context, data presented here represent the first Central and East Asian aeolian dust records in which DO events are recorded, providing a means to test hypothesized links between short-term climate variability recorded in Greenland and associated climate dynamics at Asian dust source areas. Ultimately, the data extend existing hypotheses, suggesting that the Central and High Asian mountains are a crucial element within the sensitive glacier-desert-dust response system in interior Eurasia and may be considered a pacemaker

  12. Abrupt Climate Events Recorded in Chinese and Central Asian Loess Sequences

    NASA Astrophysics Data System (ADS)

    Machalett, B.; Oches, E. A.; Haam, E. K.; Lai, Z.; Endlicher, W.

    2013-12-01

    Past climate dynamics associated with the Eurasian continent have been extensively studied. However, the impact of intra-hemispheric-scale climate variability on the entire Eurasian landmass, as well as the self-generated effects of the continent on the global climate system, is still a matter of investigation . While western Atlantic polar and tropical air masses penetrate into the continent and are transformed as they cross Eurasia, the interior regions of Eurasia strongly influence Earth's climate system. Significant cooling and heating of Central and High Asia drive interactions between atmospheric and oceanic processes and regulate teleconnection patterns across the Northern Hemisphere. This paper utilizes high resolution particle size data from the Central Asian loess sequence at Remisowka, Kazakhstan, and the long studied, monsoon-influenced Chinese loess sequence at Xifeng, to reconstruct past atmospheric circulation and aeolian dust dynamics within interior Eurasia since the last interglacial period. The observed dynamics in aeolian dust transport closely mirror d18O and fine dust variations measured in Greenland ice cores, suggesting a correlation with short-term climate oscillations (DO events) recorded therein. An Asian origin of fine aeolian dust preserved in Greenland ice cores has been discussed previously, and recent papers reveal a close link between Asian aeolian dust dynamics and DO events recorded in Greenland ice cores. In this context, data presented here represent the first Central and East Asian aeolian dust records in which DO events are recorded, providing a means to test hypothesized links between short-term climate variability recorded in Greenland and associated climate dynamics at Asian dust source areas. Ultimately, the data extend existing hypotheses, suggesting that the Central and High Asian mountains are a crucial element within the sensitive glacier-desert-dust response system in interior Eurasia and may be considered a pacemaker

  13. Monitoring physicians' prescription patterns on electronic health record: the prescription pattern around clinical event (PACE) algorithm.

    PubMed

    Yoon, Dukyong; Park, Inwhee; Park, Man Young; Hong, Seung Kwon; Park, Rae Woong

    2013-01-01

    Electronic health records (EHRs) have gained attention as a valuable data source for medical research, as its adoption rate continues to rise. However, no method for the monitoring of physicians' prescription patterns has been established. Since EHR maintain all prescription data as well as clinical events that occur during the care of patients, we hypothesized that a physician's prescription pattern can be monitored from EHR. In this study, we developed a novel algorithm named PACE, Prescription pattern Around Clinical Event. This algorithm analyzes distribution of the prescription of specific drugs around the time of a clinical event. In the proof of concept study, prescription changes with regard to hyperkalemia were well represented by the algorithm, and the observed patterns well correlated with the physician's knowledge on hyperkalemia (Cohen's kappa, 0.457-0.653). We expect that this algorithm can be used to monitor the guideline adherence of physicians.

  14. Recording event-related activity under hostile magnetic resonance environment: Is multimodal EEG/ERP-MRI recording possible?

    PubMed

    Karakaş, H M; Karakaş, S; Ozkan Ceylan, A; Tali, E T

    2009-08-01

    Event-related potentials (ERPs) have high temporal resolution, but insufficient spatial resolution; the converse is true for the functional imaging techniques. The purpose of the study was to test the utility of a multimodal EEG/ERP-MRI technique which combines electroencephalography (EEG) and magnetic resonance imaging (MRI) for a simultaneously high temporal and spatial resolution. The sample consisted of 32 healthy young adults of both sexes. Auditory stimuli were delivered according to the active and passive oddball paradigms in the MRI environment (MRI-e) and in the standard conditions of the electrophysiology laboratory environment (Lab-e). Tasks were presented in a fixed order. Participants were exposed to the recording environments in a counterbalanced order. EEG data were preprocessed for MRI-related artifacts. Source localization was made using a current density reconstruction technique. The ERP waveforms for the MRI-e were morphologically similar to those for the Lab-e. The effect of the recording environment, experimental paradigm and electrode location were analyzed using a 2x2x3 analysis of variance for repeated measures. The ERP components in the two environments showed parametric variations and characteristic topographical distributions. The calculated sources were in line with the related literature. The findings indicated effortful cognitive processing in MRI-e. The study provided preliminary data on the feasibility of the multimodal EEG/ERP-MRI technique. It also indicated lines of research that are to be pursued for a decisive testing of this technique and its implementation to clinical practice.

  15. a Marine Record of Holocene Climate Events in Tropical South America

    NASA Astrophysics Data System (ADS)

    Haug, G. H.; Günther, D.; Hughen, K. A.; Peterson, L. C.; Röhl, U.

    2002-12-01

    Metal concentration data (Ti, Fe) from the anoxic Cariaco Basin off the Venezuelan coast record with subdecadal to seasonal resolution variations in the hydrological cycle over tropical South America during the last 14 ka. Following a dry Younger Dryas, a period of increased precipitation and riverine discharge occurred during the Holocene `thermal maximum'. Since ~5.4 ka, a trend towards drier conditions is evident from the data, with high amplitude fluctuations and precipitation minima during the time interval 3.8 to 2.8 ka and during the `Little Ice Age'. O pronouced increase in precipitation coincides with the phase sometimes referred to as the `Medieval Warm Period'. These regional changes in precipitation are best explained by shifts in the mean latitude of the Atlantic Intertropical Convergence Zone (ITCZ), potentially driven by Pacific-based climate variability. The variations recorded in Cariaco Basin sediments coincide with events in societal evolution that have been suggested previously to be motivated by environmental change. Regionally, the Cariaco record supports the notion that the collapse of this civilization between 800 and 1000 AD coincided with an extended period of drier conditions, implying that the rapid growth of Mayan culture from 600 to 800 AD may have resulted in a population operating at the fringes of the environment's carrying capacity. The Cariaco Basin record also hints at tropical climate events similar in timing to high latitude changes in the North Atlantic often invoked as pivotal to societal developments in Europe.

  16. Video event data recording of a taxi driver used for diagnosis of epilepsy.

    PubMed

    Sakurai, Kotaro; Yamamoto, Junko; Kurita, Tsugiko; Takeda, Youji; Kusumi, Ichiro

    2014-01-01

    A video event data recorder (VEDR) in a motor vehicle records images before and after a traffic accident. This report describes a taxi driver whose seizures were recorded by VEDR, which was extremely useful for the diagnosis of epilepsy. The patient was a 63-year-old right-handed Japanese male taxi driver. He collided with a streetlight. Two years prior to this incident, he raced an engine for a long time while parked. The VEDR enabled confirmation that the accidents depended on an epileptic seizure and he was diagnosed with symptomatic localization-related epilepsy. The VEDR is useful not only for traffic accident evidence; it might also contribute to a driver's health care and road safety.

  17. Video event data recording of a taxi driver used for diagnosis of epilepsy☆

    PubMed Central

    Sakurai, Kotaro; Yamamoto, Junko; Kurita, Tsugiko; Takeda, Youji; Kusumi, Ichiro

    2014-01-01

    A video event data recorder (VEDR) in a motor vehicle records images before and after a traffic accident. This report describes a taxi driver whose seizures were recorded by VEDR, which was extremely useful for the diagnosis of epilepsy. The patient was a 63-year-old right-handed Japanese male taxi driver. He collided with a streetlight. Two years prior to this incident, he raced an engine for a long time while parked. The VEDR enabled confirmation that the accidents depended on an epileptic seizure and he was diagnosed with symptomatic localization-related epilepsy. The VEDR is useful not only for traffic accident evidence; it might also contribute to a driver's health care and road safety. PMID:25667862

  18. Sedimentary record of Tropical Cyclone Pam from Vanuatu: implications for long-term event records in the tropical South Pacific

    NASA Astrophysics Data System (ADS)

    Pilarczyk, Jessica; Kosciuch, Thomas; Hong, Isabel; Fritz, Hermann; Horton, Benjamin; Wallace, Davin; Dike, Clayton; Rarai, Allan; Harrison, Morris; Jockley, Fred

    2017-04-01

    Vanuatu has a history of tropical cyclones impacting its coastlines, including Tropical Cyclone (TC) Pam, a rare Category 5 event that made landfall in March 2015. Reliable records of tropical cyclones impacting Vanuatu are limited to the last several decades, with only fragmentary evidence of events extending as far back as the 1890's. Geological investigations are a means for expanding the short historical record of tropical cyclones by hundreds to thousands of years, permitting the study of even the rare, but intense events. However, geological records of past tropical cyclones are limited in their ability to quantify the intensity of past events. Modern analogues of landfalling tropical cyclones present an opportunity to characterize overwash sediments deposited by a storm of known intensity. In this study, we document the sedimentological and micropaleontological characteristics of sediments deposited by TC Pam in order to assess sediment provenance associated with a landfalling Category 5 storm. Within three months of TC Pam making landfall on Vanuatu we surveyed high-water marks associated with the storm surge and documented the foraminiferal assemblages and grain size distributions contained within the overwash sediments from Manuro (mixed-carbonate site on Efate Island) and Port Resolution Bay (volcaniclastic site on Tanna Island). The combined use of foraminiferal taxonomy and taphonomy (surface condition of foraminifera) was most useful in distinguishing the TC Pam sediments from the underlying layer. TC Pam sediments were characterized by an influx of calcareous marine foraminifera that were dominantly unaltered relative to those that were abraded and fragmented. Similar to studies that use mollusk taphonomy to identify overwash deposits, we found that TC Pam sediments were associated with an influx of angular fragments that were broken during transport by the storm surge. A statistical comparison of foraminifera from six modern environments on Efate

  19. A Neuromorphic Event-Based Neural Recording System for Smart Brain-Machine-Interfaces.

    PubMed

    Corradi, Federico; Indiveri, Giacomo

    2015-10-01

    Neural recording systems are a central component of Brain-Machince Interfaces (BMIs). In most of these systems the emphasis is on faithful reproduction and transmission of the recorded signal to remote systems for further processing or data analysis. Here we follow an alternative approach: we propose a neural recording system that can be directly interfaced locally to neuromorphic spiking neural processing circuits for compressing the large amounts of data recorded, carrying out signal processing and neural computation to extract relevant information, and transmitting only the low-bandwidth outcome of the processing to remote computing or actuating modules. The fabricated system includes a low-noise amplifier, a delta-modulator analog-to-digital converter, and a low-power band-pass filter. The bio-amplifier has a programmable gain of 45-54 dB, with a Root Mean Squared (RMS) input-referred noise level of 2.1 μV, and consumes 90 μW . The band-pass filter and delta-modulator circuits include asynchronous handshaking interface logic compatible with event-based communication protocols. We describe the properties of the neural recording circuits, validating them with experimental measurements, and present system-level application examples, by interfacing these circuits to a reconfigurable neuromorphic processor comprising an array of spiking neurons with plastic and dynamic synapses. The pool of neurons within the neuromorphic processor was configured to implement a recurrent neural network, and to process the events generated by the neural recording system in order to carry out pattern recognition.

  20. The Boltysh crater record of rapid vegetation change during the Dan-C2 hyperthermal event.

    NASA Astrophysics Data System (ADS)

    Jolley, D. W.; Daly, R.; Gilmour, I.; Gilmour, M.; Kelley, S. P.

    2012-04-01

    Analysis of a cored borehole drilled through the sedimentary fill of the 24km wide Boltysh meteorite crater, Ukraine has yielded a unique, high resolution record spanning <1my of Early Paleocene terrestrial environmental change. While the oldest crater fill sediments preserve a record of the K/Pg boundary, overlying sediments preserve a record through the earliest Danian Dan-C2 hyperthermal event. This event is preserved in ~220m of lacustrine organic mudrocks and shows close similarities to the carbon isotope records of the Toarcian and PETM CIE's. At Boltysh, the rapid sedimentation rate and lack of bioturbation in the crater fill lacustrine deposits preserve uniquely high resolution pollen, spore and algae records. These records reflect environmental change from the K/Pg1 to the post Dan-C2 Danian. Leading into the CIE, warm temperate gymnosperm - angiosperm - fern communities are replaced by precipitation limited (winterwet) plant communities within the negative CIE. Winterwet plant communities dominate the negative CIE, but are replaced within the isotope recovery stage by warm temperate floras. These in turn give way to cooler temperate floras in the post positive CIE section of the uppermost crater fill. The distribution of temperate taxa about the negative CIE represents the broadest scale of oscillatory variation in the palynofloras. Shorter frequency oscillations are evident from diversity and botanical group distributions reflecting changes in moisture availability over several thousand years. Detailed analysis of variability within one of these oscillations records plant community cyclicity across the inception of the negative CIE. This short term cyclicity provides evidence that the replacement of warm termperate by winterwet floras occurred in a stepwise manner at the negative CIE suggesting cumulative atmospheric forcing. At <1mm scale, lamination within the negative CIE showed no obvious lithological or colour differences, and are not seasonal

  1. Fast Seismic Event Classification Based On Magnitude-Distance Relation Based On Support Vector Machines Using Only One Three Component Station

    NASA Astrophysics Data System (ADS)

    Ochoa Gutierrez, L. H.; Morales, J. L.; Vargas-Jimenez, C. A.; Niño, L. F.

    2009-12-01

    When a seismic event occurs, it’s characterization is done by algorithms based only on the information received in closest seismological stations related to the particular event, ignoring all the valuable historical information received in those stations, which is stored and unseen at this stage. That’s is the reason why this labor takes some minutes that delay the response, loosing time that can be useful to decrease adverse effects to involved population. Lots of data recorded at seismological stations form nearby events, which have been characterized by classical methods, can be used as previous “knowledge” to train such stations in pattern recognition, to make a faster characterization, using some techniques like Bio-inspired algorithms or recently developed stochastic methods like Kernel Methods. We trained a Support Vector Machine Algorithm with seismographs recorded in the INGEOMINA’s National Seismological Net is a Three components seismological station called “EL ROSAL” , nearby Bogota (Colombia), the traces were splitted into 7 time windows of 2 sec. In every window was estimated the spectrum using the fourier transform. This input data and the magnitude - distance ratio are used to make a classification comparing with a threshold. We used 986 events of Magnitude bigger than 3 recorded since late 2003 to 2008. The algorithm classifies events with Magnitude-Distance relation greater than a Background value, that is a measure of Intensity. Determination of this value makes possible to obtain an estimation of the magnitude, knowing the distance from the hypocenter, calculated by difference between P and S onset times, and will let to have a very fast magnitude approximate value, in less than 20 seconds, that can be used for rapid response strategies. Results obtained in this work, give us an idea of the very useful tool to obtain many hypocentral parameters and get a very fast location of a seismic event. A cascade scheme of SVM’s or other

  2. How do olivines record magmatic events? Insights from major and trace element zoning

    NASA Astrophysics Data System (ADS)

    de Maisonneuve, C. Bouvet; Costa, F.; Huber, C.; Vonlanthen, P.; Bachmann, O.; Dungan, M. A.

    2016-06-01

    Reconciling the diverse records of magmatic events preserved by multiple crystals and minerals in the same sample is often challenging. In the case of basaltic-andesites from Volcán Llaima (Chile), Mg zoning in olivine is always simpler than Ca zoning in plagioclase. A model that explains a number of chemical patterns is that Llaima magmas stall in the upper crust, where they undergo decompression crystallization and form crystal-mush bodies. Frequent magma inputs from deeper reservoirs provide the potential for remobilization and eruption. The records of multiple recharge events in Llaima plagioclase versus an apparent maximum of one such event in coexisting olivine are addressed by using trace element zoning in olivine phenocrysts. We have integrated elements that (1) respond to changes in magma composition due to recharge or mixing (Mg, Fe, Ni, Mn, ±Ca), with (2) elements that are incorporated during rapid, disequilibrium crystal growth (P, Ti, Sc, V, Al). A more complex history is obtained when these elements are evaluated considering their partition coefficients, diffusivities, and crystal growth rates. The olivine archive can then be reconciled with the plagioclase archive of magma reservoir processes. Olivine (and plagioclase) phenocrysts may experience up to three or more recharge events between nucleation and eruption. Diffusion modeling of major and trace element zoning in two dimensions using a new lattice Boltzmann model suggests that recharge events occur on the order of months to a couple of years prior to eruption, whereas crystal residence times are more likely to be on the order of a few years to decades.

  3. Pre-Archean thermal events recorded in >4.0 Ga zircons

    NASA Astrophysics Data System (ADS)

    Trail, D.; Mojzsis, S. J.; Harrison, T. M.

    2005-12-01

    A geological record of the Hadean Earth remained inaccessible to geologists due to the apparent absence of a rock record until the discovery of pre-4.0 Ga detrital zircons in the Narryer Gneiss Complex (Western Australia) sediments (Froude et al., 1983; Compston and Pidgeon, 1986). Since then, follow-up studies have found evidence for large (present-day) amounts of continental crust with plate tectonic-style recycling (Harrison et al., 2005), liquid water at or near Earth's surface (Mojzsis et al., 2001), presence of short-lived nuclides like 244Pu (Turner et al., 2004) and zircon crystallization temperatures similar to present day water-saturated granitoids (Watson and Harrison, 2005), all within the first 200 Myr of Earth history. We report results of a continuous U-Th-Pb depth profile survey of six individual zircons ranging in age from 4317-4055 Ma by ion microprobe which provides sub-μm scale resolution bearing on zircon responses to discrete thermal events during their residence time in the crust. The earliest recognized thermal events appear coincident with mid to late Archean granitoid and gneissic assembly and emplacement in the Narryer Gneiss Complex. Two of the six zircons contain large (~25 μm) mid-Archean overgrowths mantling igneous cores. Four other zircons profiled to their core regions record separate and geologically uncorrelatable events: common ~3.9 Ga overgrowths 3-6 μm thick are present on a spatial scale otherwise inaccessible to a conventional "spot" mode (~30 μm). Post main-accretion impact fluxes of comets and asteroids would potentially have had direct influence on the terrestrial rock record; lunar meteorite melts and melt-sheet ages for the Moon predict a statistical increase in impactor flux between 4.0-3.92 Ga (Tera et al., 1974; Cohen et al., 2000; Ryder, 2002). Dynamical models predict scaled impact events on the Earth during the "lunar cataclysm" (e.g. Sleep and Zahnle, 1998). Our depth profile results from Hadean zircons

  4. Event related potentials recorded in patients with locked-in syndrome

    PubMed Central

    Onofrj, M.; Thomas, A.; Paci, C.; Scesi, M.; Tombari, R.

    1997-01-01

    OBJECTIVE—To determine the possibility of recording "cognitive" event related potentials (ERPs) in locked-in patients and therefore to determine whether ERPs can have a role in differential diagnosis of coma.
METHODS—ERPs to classic auditory or visual "odd ball paradigms" were recorded three to four days, seven to eight days, and 30 to 60days after admission to the intensive care unit, in four patients affected by basilar artery thrombembolism resulting in locked-in syndrome. Two patients (one 32 year old man, one 31 year old woman) could move the eyes laterally and vertically spontaneously and on command. One patient (a 39 year old man) had a "one and half syndrome", one patient (a 40 year old woman) could only elevate the left eyelid and eye. Results were compared with data from 30 age matched controls. In the last recording session a letter recognition paradigm was applied, in which ERPs were produced by the identification of letters forming a word. Results were compared with five age matched controls. Brainstem lesions extending to the pontomesencephalic junction were found on MRI and CT.
RESULTS—ERPs to the oddball paradigms were recorded in three patients in the first recording session, in all patients in the second recording session. Latency, amplitude, and topographic distribution of ERP components were inside normal limits. With the letter recognition paradigm the patients could emit a P3 component to correspond with target letters, with the same margin of error as controls.
CONCLUSION—It is possible to record ERPs in patients with locked-in syndrome shortly after the acute ischaemic lesion, and therefore to assess objectively cognitive activities. Furthermore the letter recognition paradigm could be implemented to facilitate linguistic communication with patients with locked-in syndrome.

 PMID:9416812

  5. Recordings of mucociliary activity in vivo: benefit of fast Fourier transformation of the photoelectric signal.

    PubMed

    Lindberg, S; Cervin, A; Runer, T; Thomasson, L

    1996-09-01

    Investigations of mucociliary activity in vivo are based on photoelectric recordings of light reflections from the mucosa. The alterations in light intensity produced by the beating cilia are picked up by a photodetector and converted to photoelectric signals. The optimal processing of these signals is not known, but in vitro recordings have been reported to benefit from fast Fourier transformation (FFT) of the signal. The aim of the investigation was to study the effect of FFT for frequency analysis of photoelectric signals originating from an artificial light source simulating mucociliary activity or from sinus or nasal mucosa in vivo, as compared to a conventional method of calculating mucociliary wave frequency, in which each peak in the signal is interpreted as a beat (old method). In the experiments with the artificial light source, the FFT system was superior to the conventional method by a factor of 50 in detecting weak signals. By using FFT signal processing, frequency could be correctly calculated in experiments with a compound signal. In experiments in the rabbit maxillary sinus, the spontaneous variations were greater when signals were processed by FFT. The correlation between the two methods was excellent: r = .92. The increase in mucociliary activity in response to the ciliary stimulant methacholine at a dosage of 0.5 microgram/kg was greater measured with the FFT than with the old method (55.3% +/- 8.3% versus 43.0% +/- 8.2%, p < .05, N = 8), and only with the FFT system could a significant effect of a threshold dose (0.05 microgram/kg) of methacholine be detected. In the human nose, recordings from aluminum foil placed on the nasal dorsum and from the nasal septa mucosa displayed some similarities in the lower frequency spectrum (< 5 Hz) attributable to artifacts. The predominant cause of these artifacts was the pulse beat, whereas in the frequency spectrum above 5 Hz, results differed for the two sources of reflected light, the mean frequency in

  6. Efficient panel designs for longitudinal recurrent event studies recording panel counts.

    PubMed

    Juarez-Colunga, Elizabeth; Dean, C B; Balshaw, Robert

    2014-04-01

    Many clinical trials are designed to study outcome measures recorded as the number of events occurring during specific intervals, called panel data. In such data, the intervals are specified by a planned set of follow-up times. As the collection of panel data results in a partial loss of information relative to a record of the actual event times, it is important to gain a thorough understanding of the impact of panel study designs on the efficiency of the estimates of treatment effects and covariates. This understanding can then be used as a base from which to formulate appropriate designs by layering in other concerns, e.g. clinical constraints, or other practical considerations. We compare the efficiency of the analysis of panel data with respect to the analysis of data recorded precisely as times of recurrences, and articulate conditions for efficient panel designs where the focus is on estimation of a treatment effect when adjusting for other covariates. We build from the efficiency comparisons to optimize the design of panel follow-up times. We model the recurrent intensity through the common proportional intensity framework, with the treatment effect modeled flexibly as piecewise constant over panels, or groups of panels. We provide some important considerations for the design of efficient panel studies, and illustrate the methods through analysis of designs of studies of adenomas.

  7. Transient thrust events recorded in the Aare Massif, Bernese Alps (Grimsel Test Site, Switzerland)

    NASA Astrophysics Data System (ADS)

    Hartvich, F.; Stemberk, J.

    2016-12-01

    The Grimsel Test Site (GTS) is located at an altitude of 1730 m a.s.l. in the granitic formations of the Aare Massif 300 - 500 m under the surface. In November 2012, documented faults within the GTS were instrumented for 3-D monitoring of fault slips in the scope of the LArge Scale MOnitoring project (LASMO). In total 7 devices were installed across faults crossing a 350 m long section of the GTS. The instrumented faults have various strike: W-E, SW-NE, WNW-ESE and WSW-ENE. The faults are instrumented with optical-mechanical extensometers TM71 which allow to measure 3D micro-displacements as well as rotations on the basis of the moiré effect of optical interference. The devices installed in GTS reach the accuracy better than 0.007 mm and the angular deviation between two blocks separated by a discontinuity - i.e. their relative rotation - can be measured with a resolution better than 0.00016 rad. Regular monitoring has started on Dec. 5,2012 and the reading is performed regularly once per day. The first results of 3-D fault displacement monitoring show transient slips recorded during 2 short periods along all monitored faults, alternating with long periods of tectonic quiescence without any fault activity. The measured directions of fault slips enable us to estimate two approximately N - S oriented compression events, causing northwards thrust movements. First period lasted from Dec. 27, 2012 to Feb. 13, 2013. However, major phase of the displacement occurred between Jan. 26 and 29, 2013. Recorded fault slips represent northwards oriented thrusts and strike-slips. A value of individual slips ranges from 0.004 to 0.04 mm. Moreover, the strike-slip movements were recorded during days when two local micro-earthquakes were observed close to GTS: on Jan. 29, 2013 (M = 1.29) and on Feb. 13, 2013 (M = 1.15). The second period of activity lasted from Sept. 7, 2013 to Oct. 28, 2013, and occurred after more than 7 months of no recorded fault slips. The main phase of the

  8. Fast multi-feature paradigm for recording several mismatch negativities (MMNs) to phonetic and acoustic changes in speech sounds.

    PubMed

    Pakarinen, Satu; Lovio, Riikka; Huotilainen, Minna; Alku, Paavo; Näätänen, Risto; Kujala, Teija

    2009-12-01

    In this study, we addressed whether a new fast multi-feature mismatch negativity (MMN) paradigm can be used for determining the central auditory discrimination accuracy for several acoustic and phonetic changes in speech sounds. We recorded the MMNs in the multi-feature paradigm to changes in syllable intensity, frequency, and vowel length, as well as for consonant and vowel change, and compared these MMNs to those obtained with the traditional oddball paradigm. In addition, we examined the reliability of the multi-feature paradigm by repeating the recordings with the same subjects 1-7 days after the first recordings. The MMNs recorded with the multi-feature paradigm were similar to those obtained with the oddball paradigm. Furthermore, only minor differences were observed in the MMN amplitudes across the two recording sessions. Thus, this new multi-feature paradigm with speech stimuli provides similar results as the oddball paradigm, and the MMNs recorded with the new paradigm were reproducible.

  9. Ultra-high throughput real-time instruments for capturing fast signals and rare events

    NASA Astrophysics Data System (ADS)

    Buckley, Brandon Walter

    processing. The act of time-stretching effectively boosts the performance of the back-end electronics and digital signal processors. The slowed down signals reach the back-end electronics with reduced bandwidth, and are therefore less affected by high-frequency roll-off and distortion. Time-stretching also increases the effective sampling rate of analog-to-digital converters and reduces aperture jitter, thereby improving resolution. Finally, the instantaneous throughputs of digital signal processors are enhanced by the stretch factor to otherwise unattainable speeds. Leveraging these unique capabilities, TiSER becomes the ideal tool for capturing high-speed signals and characterizing rare phenomena. For this thesis, I have developed techniques to improve the spectral efficiency, bandwidth, and resolution of TiSER using polarization multiplexing, all-optical modulation, and coherent dispersive Fourier transformation. To reduce the latency and improve the data handling capacity, I have also designed and implemented a real-time digital signal processing electronic backend, achieving 1.5 tera-bit per second instantaneous processing throughput. Finally, I will present results from experiments highlighting TiSER's impact in real-world applications. Confocal fluorescence microscopy is the most widely used method for unveiling the molecular composition of biological specimens. However, the weak optical emission of fluorescent probes and the tradeoff between imaging speed and sensitivity is problematic for acquiring blur-free images of fast phenomena and cells flowing at high speed. Here I introduce a new fluorescence imaging modality, which leverages techniques from wireless communication to reach record pixel and frame rates. Termed Fluorescence Imaging using Radio-frequency tagged Emission (FIRE), this new imaging modality is capable of resolving never before seen dynamics in living cells - such as action potentials in neurons and metabolic waves in astrocytes - as well as

  10. A Luminous, Fast Rising UV-transient Discovered by ROTSE: A Tidal Disruption Event?

    NASA Astrophysics Data System (ADS)

    Vinkó, J.; Yuan, F.; Quimby, R. M.; Wheeler, J. C.; Ramirez-Ruiz, E.; Guillochon, J.; Chatzopoulos, E.; Marion, G. H.; Akerlof, C.

    2015-01-01

    We present follow-up observations of an optical transient (OT) discovered by ROTSE on 2009 January 21. Photometric monitoring was carried out with ROTSE-IIIb in the optical and Swift in the UV up to +70 days after discovery. The light curve showed a fast rise time of ~10 days followed by a steep decline over the next 60 days, which was much faster than that implied by 56Ni—56Co radioactive decay. The Sloan Digital Sky Survey Data Release 10 database contains a faint, red object at the position of the OT, which appears slightly extended. This and other lines of evidence suggest that the OT is of extragalactic origin, and this faint object is likely the host galaxy. A sequence of optical spectra obtained with the 9.2 m Hobby-Eberly Telescope between +8 and +45 days after discovery revealed a hot, blue continuum with no visible spectral features. A few weak features that appeared after +30 days probably originated from the underlying host. Fitting synthetic templates to the observed spectrum of the host galaxy revealed a redshift of z = 0.19. At this redshift, the peak magnitude of the OT is close to -22.5, similar to the brightest super-luminous supernovae; however, the lack of identifiable spectral features makes the massive stellar death hypothesis less likely. A more plausible explanation appears to be the tidal disruption of a Sun-like star by the central supermassive black hole. We argue that this transient likely belongs to a class of super-Eddington tidal disruption events.

  11. A LUMINOUS, FAST RISING UV-TRANSIENT DISCOVERED BY ROTSE: A TIDAL DISRUPTION EVENT?

    SciTech Connect

    Vinkó, J.; Wheeler, J. C.; Chatzopoulos, E.; Marion, G. H.; Yuan, F.; Akerlof, C.; Quimby, R. M.; Ramirez-Ruiz, E.; Guillochon, J.

    2015-01-01

    We present follow-up observations of an optical transient (OT) discovered by ROTSE on 2009 January 21. Photometric monitoring was carried out with ROTSE-IIIb in the optical and Swift in the UV up to +70 days after discovery. The light curve showed a fast rise time of ∼10 days followed by a steep decline over the next 60 days, which was much faster than that implied by {sup 56}Ni—{sup 56}Co radioactive decay. The Sloan Digital Sky Survey Data Release 10 database contains a faint, red object at the position of the OT, which appears slightly extended. This and other lines of evidence suggest that the OT is of extragalactic origin, and this faint object is likely the host galaxy. A sequence of optical spectra obtained with the 9.2 m Hobby-Eberly Telescope between +8 and +45 days after discovery revealed a hot, blue continuum with no visible spectral features. A few weak features that appeared after +30 days probably originated from the underlying host. Fitting synthetic templates to the observed spectrum of the host galaxy revealed a redshift of z = 0.19. At this redshift, the peak magnitude of the OT is close to –22.5, similar to the brightest super-luminous supernovae; however, the lack of identifiable spectral features makes the massive stellar death hypothesis less likely. A more plausible explanation appears to be the tidal disruption of a Sun-like star by the central supermassive black hole. We argue that this transient likely belongs to a class of super-Eddington tidal disruption events.

  12. Nonlinear cross-bridge elasticity and post-power-stroke events in fast skeletal muscle actomyosin.

    PubMed

    Persson, Malin; Bengtsson, Elina; ten Siethoff, Lasse; Månsson, Alf

    2013-10-15

    Generation of force and movement by actomyosin cross-bridges is the molecular basis of muscle contraction, but generally accepted ideas about cross-bridge properties have recently been questioned. Of the utmost significance, evidence for nonlinear cross-bridge elasticity has been presented. We here investigate how this and other newly discovered or postulated phenomena would modify cross-bridge operation, with focus on post-power-stroke events. First, as an experimental basis, we present evidence for a hyperbolic [MgATP]-velocity relationship of heavy-meromyosin-propelled actin filaments in the in vitro motility assay using fast rabbit skeletal muscle myosin (28-29°C). As the hyperbolic [MgATP]-velocity relationship was not consistent with interhead cooperativity, we developed a cross-bridge model with independent myosin heads and strain-dependent interstate transition rates. The model, implemented with inclusion of MgATP-independent detachment from the rigor state, as suggested by previous single-molecule mechanics experiments, accounts well for the [MgATP]-velocity relationship if nonlinear cross-bridge elasticity is assumed, but not if linear cross-bridge elasticity is assumed. In addition, a better fit is obtained with load-independent than with load-dependent MgATP-induced detachment rate. We discuss our results in relation to previous data showing a nonhyperbolic [MgATP]-velocity relationship when actin filaments are propelled by myosin subfragment 1 or full-length myosin. We also consider the implications of our results for characterization of the cross-bridge elasticity in the filament lattice of muscle.

  13. Fast-track extreme event attribution: General methods and techniques to determine the dynamic contribution to an event.

    NASA Astrophysics Data System (ADS)

    Otto, F. E. L.; Haustein, K.; Uhe, P.; Massey, N.; Rimi, R.; Allen, M. R.; Cullen, H. M.

    2016-12-01

    Extreme weather event attribution has become an accepted part of the atmospheric sciences with numerous methods having been put forward over the last decade. We have recently established a new framework which allows for event attribution in quasi-real-time. Here we present the methodology with which we can assess the fraction of attributable risk (FAR) of a severe weather event due to an external driver (Haustein et al. 2016). The method builds on a large ensemble of atmosphere-only GCM simulations forced by seasonal forecast SSTs (actual conditions) that are contrasted with ensembles forced by counterfactual SSTs (natural conditions). Having an associated 30 year actual and natural climatology in place, we are able to put the current event into a climatological context and determine the dynamic contribution that lead to the event as opposed to the thermodynamic contribution which would have made such an event more likely regardless of the synoptic situation. As a second independent method (also applicable in near-real-time), we apply pattern correlation to separate thermodynamic and dynamic contributions. Finally, using reanalysis data, we test whether our attributed dynamic contribution is also detectable in the observations. Despite the high monthly variability, ENSO related teleconnection patterns can be detected fairly robustly as we will demonstrate with a recent example during El Nino. The more consistent the 3 methods are, the more robust our results will be. We note that the choice of time scale matters a lot when determining the dynamic contribution as well as estimating the FAR (Uhe et al. 2016). The weather@home ensemble prediction approach is accompanied by two more methods based on observational data and the CMIP5 ensemble. If the FAR across 3 methods is consistent, we have reason to trust our central attribution statement. Two recent examples will be shown in order to demonstrate the feasibility (van Oldenborgh et al. 2016a/2016b), complemented by

  14. Selected plant microfossil records of the terminal Cretaceous event in terrestrial rocks, western North America

    USGS Publications Warehouse

    Nichols, D.J.

    2007-01-01

    Terrestrial or nonmarine rocks of western North America preserve a record of major disruption and permanent alteration of plant communities precisely at the K-T boundary - in the same rocks that preserve geochemical and mineralogical evidence of the terminal Cretaceous impact event. Plant microfossil records from many localities show abrupt disappearance of pollen species (= plant extinctions) closely associated with impact ejecta deposits containing iridium and shocked quartz. Localities discussed in detail in this review are Starkville South, Clear Creek North, Old Raton Pass, and Sugarite in the Raton Basin of Colorado and New Mexico; West Bijou in the Denver Basin, Colorado; Sussex in the Powder River Basin, Wyoming; and Pyramid Butte and Mud Buttes in the Williston Basin, North Dakota. ?? 2007 Elsevier B.V. All rights reserved.

  15. Biotic immigration events, speciation, and the accumulation of biodiversity in the fossil record

    NASA Astrophysics Data System (ADS)

    Stigall, Alycia L.; Bauer, Jennifer E.; Lam, Adriane R.; Wright, David F.

    2017-01-01

    Biotic Immigration Events (BIMEs) record the large-scale dispersal of taxa from one biogeographic area to another and have significantly impacted biodiversity throughout geologic time. BIMEs associated with biodiversity increases have been linked to ecologic and evolutionary processes including niche partitioning, species packing, and higher speciation rates. Yet substantial biodiversity decline has also been documented following BIMEs due to elevated extinction and/or reduced speciation rates. In this review, we develop a conceptual model for biodiversity accumulation that links BIMEs and geographic isolation with local (α) diversity, regional (β) diversity, and global (γ) diversity metrics. Within the model, BIME intervals are characterized by colonization of existing species within new geographic regions and a lack of successful speciation events. Thus, there is no change in γ-diversity, and α-diversity increases at the cost of β-diversity. An interval of regional isolation follows in which lineage splitting results in successful speciation events and diversity increases across all three metrics. Alternation of these two regimes can result in substantial biodiversity accumulation. We tested this conceptual model using a series of case studies from the paleontological record. We primarily focus on two intervals during the Middle through Late Ordovician Period (470-458 Ma): the globally pervasive BIMEs during the Great Ordovician Biodiversification Event (GOBE) and a regional BIME, the Richmondian Invasion. We further test the conceptual model by examining the Great Devonian Interchange, Neogene mollusk migrations and diversification, and the Great American Biotic Interchange. Paleontological data accord well with model predictions. Constraining the mechanisms of biodiversity accumulation provides context for conservation biology. Because α-, β-, and γ-diversity are semi-independent, different techniques should be considered for sustaining various

  16. Network Event Recording Device: An automated system for Network anomaly detection, and notification. Draft

    SciTech Connect

    Simmons, D.G.; Wilkins, R.

    1994-09-01

    The goal of the Network Event Recording Device (NERD) is to provide a flexible autonomous system for network logging and notification when significant network anomalies occur. The NERD is also charged with increasing the efficiency and effectiveness of currently implemented network security procedures. While it has always been possible for network and security managers to review log files for evidence of network irregularities, the NERD provides real-time display of network activity, as well as constant monitoring and notification services for managers. Similarly, real-time display and notification of possible security breaches will provide improved effectiveness in combating resource infiltration from both inside and outside the immediate network environment.

  17. High-density MEA recordings unveil the dynamics of bursting events in Cell Cultures.

    PubMed

    Lonardoni, Davide; Di Marco, Stefano; Amin, Hayder; Maccione, Alessandro; Berdondini, Luca; Nieus, Thierry

    2015-08-01

    High density multielectrode arrays (MEAs) based on CMOS technology (CMOS-MEAs) can simultaneously record extracellular spiking activity in neuronal cultures from 4096 closely spaced microelectrodes. This allows for a finer investigation of neuronal network activity compared to conventional MEAs with a few tens of electrodes. However, the sensing properties of these devices differ. To highlight this aspect, here we investigate and discuss the differences observed when quantifying spontaneous synchronized bursting events (SBEs) in datasets acquired with conventional MEAs and high-density MEAs from comparable hippocampal cultures. We found that datasets acquired with high-density MEAs exhibit collective dynamics similar to conventional arrays, but are characterized by a higher percentage of random spikes, i.e. spikes that are not part of a burst, most probably resulting from the larger recording capability. Additionally, the percentage of electrodes that record a burst is remarkably small on high-density MEAs compared to what can be observed on conventional MEAs and SBEs appear to be propagating in time across the electrode array, by involving shorter sequences of spikes per electrode. Overall, these results highlight a lower level of network synchronization involved in SBEs compared to what has been debated for several decades based on conventional MEA recordings from cell cultures.

  18. R2R Eventlogger: Community-wide Recording of Oceanographic Cruise Science Events

    NASA Astrophysics Data System (ADS)

    Maffei, A. R.; Chandler, C. L.; Stolp, L.; Lerner, S.; Avery, J.; Thiel, T.

    2012-12-01

    Methods used by researchers to track science events during a science research cruise - and to note when and where these occur - varies widely. Handwritten notebooks, printed forms, watch-keeper logbooks, data-logging software, and customized software have all been employed. The quality of scientific results is affected by the consistency and care with which such events are recorded and integration of multi-cruise results is hampered because recording methods vary widely from cruise to cruise. The Rolling Deck to Repository (R2R) program has developed an Eventlogger system that will eventually be deployed on most vessels in the academic research fleet. It is based on the open software package called ELOG (http://midas.psi.ch/elog/) originally authored by Stefan Ritt and enhanced by our team. Lessons have been learned in its development and use on several research cruises. We have worked hard to find approaches that encourage cruise participants to use tools like the eventlogger. We examine these lessons and several eventlogger datasets from past cruises. We further describe how the R2R Science Eventlogger works in concert with the other R2R program elements to help coordinate research vessels into a coordinated mobile observing fleet. Making use of data collected on different research cruises is enabled by adopting common ways of describing science events, the science instruments employed, the data collected, etc. The use of controlled vocabularies and the practice of mapping these local vocabularies to accepted oceanographic community vocabularies helps to bind shipboard research events from different cruises into a more cohesive set of fleet-wide events that can be queried and examined in a cross-cruise manner. Examples of the use of the eventlogger during multi-cruise oceanographic research programs along with examples of resultant eventlogger data will be presented. Additionally we will highlight the importance of vocabulary use strategies to the success of the

  19. [Systematic recording of perioperative events associated with anesthesia as quality indicator in ambulatory anesthesia].

    PubMed

    García-Aguado, R; Vivó Benlloch, M; Arcusa Mon, M J; Peiró Alós, C; Zaragoza Fernández, C; Castaño Conesa, S; Grau Real, F

    2000-03-01

    To analyze the quality of several anesthetic techniques used for major outpatient surgery in our hospital, by quantifying for each the relative risk (RR) of adverse events during anesthesia and in the postoperative period. One thousand seventeen patients who underwent surgery between 18 May 1998 and 23 October 1998 were studied retrospectively. The mean age of the patients was 52.27 +/- 24.65 yr; 44.18% were ASA I, 40.56% were ASA II, 14.56% ASA III and 0.67% ASA IV. Mean time of surgery was 33 +/- 16.49 min and mean recovery time until discharge was 77.3 +/- 93.4 min. Admission was necessary for 0.6% of the patients and re-admission for 0.3%. General anesthesia was used with 19%, anesthetic monitoring with 17%, regional anesthesia (including peribulbar) with 46% and local anesthesia plus sedation with 16.6%. In 95% of the cases, no adverse events occurred during anesthesia; in 94.8% no such events occurred during the early recovery period. During surgery and postoperative recovery, intradural anesthesia was associated with significantly greater RR of adverse events in comparison with general anesthesia (6.6 and 2.2 respectively) and in comparison with monitored anesthesia (7.2 and 3.3). No differences in RR were found between general anesthesia and monitored anesthesia. Problems were slight to moderate in severity and mainly related to nausea and vomiting (2%). Recording perioperative events permits evaluation of the quality of anesthesic procedures. Intradural anesthesia is associated with more complications.

  20. Multifocal fluorescence microscope for fast optical recordings of neuronal action potentials.

    PubMed

    Shtrahman, Matthew; Aharoni, Daniel B; Hardy, Nicholas F; Buonomano, Dean V; Arisaka, Katsushi; Otis, Thomas S

    2015-02-03

    In recent years, optical sensors for tracking neural activity have been developed and offer great utility. However, developing microscopy techniques that have several kHz bandwidth necessary to reliably capture optically reported action potentials (APs) at multiple locations in parallel remains a significant challenge. To our knowledge, we describe a novel microscope optimized to measure spatially distributed optical signals with submillisecond and near diffraction-limit resolution. Our design uses a spatial light modulator to generate patterned illumination to simultaneously excite multiple user-defined targets. A galvanometer driven mirror in the emission path streaks the fluorescence emanating from each excitation point during the camera exposure, using unused camera pixels to capture time varying fluorescence at rates that are ∼1000 times faster than the camera's native frame rate. We demonstrate that this approach is capable of recording Ca(2+) transients resulting from APs in neurons labeled with the Ca(2+) sensor Oregon Green Bapta-1 (OGB-1), and can localize the timing of these events with millisecond resolution. Furthermore, optically reported APs can be detected with the voltage sensitive dye DiO-DPA in multiple locations within a neuron with a signal/noise ratio up to ∼40, resolving delays in arrival time along dendrites. Thus, the microscope provides a powerful tool for photometric measurements of dynamics requiring submillisecond sampling at multiple locations. Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  1. Multifocal Fluorescence Microscope for Fast Optical Recordings of Neuronal Action Potentials

    PubMed Central

    Shtrahman, Matthew; Aharoni, Daniel B.; Hardy, Nicholas F.; Buonomano, Dean V.; Arisaka, Katsushi; Otis, Thomas S.

    2015-01-01

    In recent years, optical sensors for tracking neural activity have been developed and offer great utility. However, developing microscopy techniques that have several kHz bandwidth necessary to reliably capture optically reported action potentials (APs) at multiple locations in parallel remains a significant challenge. To our knowledge, we describe a novel microscope optimized to measure spatially distributed optical signals with submillisecond and near diffraction-limit resolution. Our design uses a spatial light modulator to generate patterned illumination to simultaneously excite multiple user-defined targets. A galvanometer driven mirror in the emission path streaks the fluorescence emanating from each excitation point during the camera exposure, using unused camera pixels to capture time varying fluorescence at rates that are ∼1000 times faster than the camera’s native frame rate. We demonstrate that this approach is capable of recording Ca2+ transients resulting from APs in neurons labeled with the Ca2+ sensor Oregon Green Bapta-1 (OGB-1), and can localize the timing of these events with millisecond resolution. Furthermore, optically reported APs can be detected with the voltage sensitive dye DiO-DPA in multiple locations within a neuron with a signal/noise ratio up to ∼40, resolving delays in arrival time along dendrites. Thus, the microscope provides a powerful tool for photometric measurements of dynamics requiring submillisecond sampling at multiple locations. PMID:25650920

  2. On the fingerprint of ssw events in infrasound recordings at IMS stations

    NASA Astrophysics Data System (ADS)

    Ceranna, L.; Le Pichon, A.; Pilger, C.; Ross, O.

    2013-12-01

    It has been recently shown that sudden stratospheric warming (ssw) events have an impact on the detection of coherent infrasonic waves at dedicated arrays (e.g., Evers & Siegmund, 2009). During ssw events the polar vortex of prevailing stratospheric westerly winds in a winter hemisphere abruptly slows down or even reverses its direction along with an increase of stratospheric temperatures up to several tens of °C. Since infrasound arrays are mostly recording signals ducted in stratospheric wave-guides, such antennas are sensitive to changes in effective sound speed profiles - temperature plus wind speed in direction of propagation. Considering continuous infrasonic waves emitted by ocean swell (microbaroms), volcanoes or even anthropogenic sources as flares, a gap or a change in the back-azimuth of these detected signals can be observed at arrays. For the compliances with the verification of the Comprehensive Nuclear-Test-Ban Treaty a global network of 60 infrasound stations is under construction as a part of the International Monitoring System (IMS); whereas 45 have already been installed. Analysis of waveform data recorded at these stations has demonstrated the capability of infrasound as a supplementary tool for remote sensing of the atmosphere. In our study we compare the re-analysis, using PMCC, of more than five years of continuous data at all available sites (see Matoza et al., 2013) with atmospheric descriptions provided by the EMCWF. We present a synoptic view of the fingerprint of ssw events in detection of coherent signals at IMS infrasound stations both on northern and southern hemisphere, covering the full latitude range from Antarctica to Greenland.

  3. On the fingerprint of ssw events in infrasound recordings at IMS stations

    NASA Astrophysics Data System (ADS)

    Ceranna, Lars; Pilger, Christoph; Ross, Ole; Le Pichon, Alexis

    2013-04-01

    It has been recently shown that sudden stratospheric warming (ssw) events have an impact on the detection of coherent infrasonic waves at dedicated arrays (e.g., Evers & Siegmund, 2009). During ssw events the polar vortex of prevailing stratospheric westerly winds in a winter hemisphere abruptly slows down or even reverses its direction along with an increase of stratospheric temperatures up to several tens of °C. Since infrasound arrays are mostly recording signals ducted in stratospheric wave-guides, such antennas are sensitive to changes in effective sound speed profiles - temperature plus wind speed in direction of propagation. Considering continuous infrasonic waves emitted by ocean swell (microbaroms), volcanoes or even anthropogenic sources as flares, a gap or a change in the back-azimuth of these detected signals can be observed at arrays. For the compliances with the verification of the Comprehensive Nuclear-Test-Ban Treaty a global network of 60 infrasound stations is under construction as a part of the International Monitoring System (IMS); whereas 45 have already been installed. Analysis of waveform data recorded at these stations has demonstrated the capability of infrasound as a supplementary tool for remote sensing of the atmosphere. In our study we compare the re-analysis, using PMCC, of more than five years of continuous data at all available sites (see Matoza et al., 2013) with atmospheric descriptions provided by the EMCWF. We present a synoptic view of the fingerprint of ssw events in detection of coherent signals at IMS infrasound stations both on northern and southern hemisphere, covering the full latitude range from Antarctica to Greenland.

  4. Adverse events are common on the intensive care unit: results from a structured record review.

    PubMed

    Nilsson, L; Pihl, A; Tågsjö, M; Ericsson, E

    2012-09-01

    Intensive care is advanced and highly technical, and it is essential that, despite this, patient care remains safe and of high quality. Adverse events (AEs) are supposed to be reported to internal quality control systems by health-care providers, but many are never reported. Patients on the intensive care unit (ICU) are at special risk for AEs. Our aim was to identify the incidence and characteristics of AEs in patients who died on the ICU during a 2-year period. A structured record review according to the Global Trigger Tool (GTT) was used to review charts from patients cared for at the ICU of a middle-sized Swedish hospital during 2007 and 2008 and who died during or immediately after ICU care. All identified AEs were scored according to severity and preventability. We reviewed 128 records, and 41 different AEs were identified in 25 patients (19.5%). Health care-associated infections, hypoglycaemia, pressure sores and procedural complications were the most common harmful events. Twenty two (54%) of the AEs were classified as being avoidable. Two of the 41 AEs were reported as complications according to the Swedish Intensive Care Registry, and one AE had been reported in the internal AE-reporting system. Almost one fifth of the patients who died on the ICU were subjected to harmful events. GTT has the advantage of identifying more patient injuries caused by AEs than the traditional AE-reporting systems used on many ICUs. © 2012 The Authors. Acta Anaesthesiologica Scandinavica © 2012 The Acta Anaesthesiologica Scandinavica Foundation.

  5. Contrasting sediment records of marine submersion events related to wave exposure, Southwest France

    NASA Astrophysics Data System (ADS)

    Baumann, J.; Chaumillon, E.; Schneider, J.-L.; Jorissen, F.; Sauriau, P.-G.; Richard, P.; Bonnin, J.; Schmidt, S.

    2017-05-01

    Sediment records of two contrasting backshore coastal marshes, extremely vulnerable to recent and historical marine flooding events, located on the SW coast of France, have been investigated using a multiproxy approach. The studied marshes are 30 km apart and have been flooded by similar storm events (7 marine floods in the last 250 years). One is located in a wave-exposed coast but isolated from the sea by a sediment barrier, whereas the other is located in a sheltered estuarine environment and isolated from the sea by a dike. One core was collected in each marsh and information on grain-size, foraminifera, shell contents and stable carbon isotopes was obtained along with an age model using 210Pb, 137Cs and 14C. Core data combined with historical maps give evidence of a typical estuarine backfilling, part of the Holocene regressive parasequence, including an intertidal mudflat at the base and a backshore environment at the top. Despite the absence of grain size anomalies, marine flood-related sedimentation in the backshore area of both marshes is identified by a mixture of marine and terrestrial features, including marine fauna, vegetation debris and variation in the δ13C signature of the organic fraction. Very low sedimentation rates between flood events and/or bioturbation prevents the identification of individual episodic marine floods in the sediment succession. Comparison of the two sedimentary successions shows that the foraminifera deposited by marine submersions are of two different types. Foraminifera are monospecific and originate from the upper tidal mudflat in the sheltered marsh; whereas in the backshore marsh located in a wave-exposed environment, they show higher diversity and originate from both shallow and deeper water marine environments. This study shows that wave exposure can control the faunal content of marine flood sediment records in coastal marshes.

  6. rbamtools: an R interface to samtools enabling fast accumulative tabulation of splicing events over multiple RNA-seq samples.

    PubMed

    Kaisers, Wolfgang; Schaal, Heiner; Schwender, Holger

    2015-05-15

    The open source environment R isf the most widely used software to statistically explore biological data sets including sequence alignments. BAM is the de facto standard file format for sequence alignment. With rbamtools, we provide now a full spectrum of accessibility to BAM for R users such as reading, writing, extraction of subsets and plotting of alignment depth where the script syntax closely follows the SAM/BAM format. Additionally, rbamtools enables fast accumulative tabulation of splicing events over multiple BAM files.

  7. The surface of Mars: An unusual laboratory that preserves a record of catastrophic and unusual events

    USGS Publications Warehouse

    Chapman, M.G.

    2009-01-01

    Catastrophic and unusual events on Earth such as bolide impacts, megafloods, supereruptions, flood volcanism, and subice volcanism may have devastating effects when they occur. Although these processes have unique characteristics and form distinctive features and deposits, we have diffi culties identifying them and measuring the magnitude of their effects. Our diffi culties with interpreting these processes and identifying their consequences are understandable considering their infrequency on Earth, combined with the low preservation potential of their deposits in the terrestrial rock record. Although we know these events do happen, they are infrequent enough that the deposits are poorly preserved on the geologically active face of the Earth, where erosion, volcanism, and tectonism constantly change the surface. Unlike the Earth, on Mars catastrophic and unusual features are well preserved because of the slow modifi cation of the surface. Signifi cant precipitation has not occurred on Mars for billions of years and there appears to be no discrete crustal plates to have undergone subduction and destruction. Therefore the ancient surface of Mars preserves geologic features and deposits that result from these extraordinary events. Also, unlike the other planets, Mars is the most similar to our own, having an atmosphere, surface ice, volcanism, and evidence of onceflowing water. So although our understanding of precursors, processes, and possible biological effects of catastrophic and unusual processes is limited on Earth, some of these mysteries may be better understood through investigating the surface of Mars. ?? 2009 The Geological Society of America.

  8. On decomposing stimulus and response waveforms in event-related potentials recordings.

    PubMed

    Yin, Gang; Zhang, Jun

    2011-06-01

    Event-related potentials (ERPs) reflect the brain activities related to specific behavioral events, and are obtained by averaging across many trial repetitions with individual trials aligned to the onset of a specific event, e.g., the onset of stimulus (s-aligned) or the onset of the behavioral response (r-aligned). However, the s-aligned and r-aligned ERP waveforms do not purely reflect, respectively, underlying stimulus (S-) or response (R-) component waveform, due to their cross-contaminations in the recorded ERP waveforms. Zhang [J. Neurosci. Methods, 80, pp. 49-63, 1998] proposed an algorithm to recover the pure S-component waveform and the pure R-component waveform from the s-aligned and r-aligned ERP average waveforms-however, due to the nature of this inverse problem, a direct solution is sensitive to noise that disproportionally affects low-frequency components, hindering the practical implementation of this algorithm. Here, we apply the Wiener deconvolution technique to deal with noise in input data, and investigate a Tikhonov regularization approach to obtain a stable solution that is robust against variances in the sampling of reaction-time distribution (when number of trials is low). Our method is demonstrated using data from a Go/NoGo experiment about image classification and recognition.

  9. Ramadan fasting is not usually associated with the risk of cardiovascular events: A systematic review and meta-analysis

    PubMed Central

    Turin, Tanvir C.; Ahmed, Salim; Shommu, Nusrat S.; Afzal, Arfan R.; Al Mamun, Mohammad; Qasqas, Mahdi; Rumana, Nahid; Vaska, Marcus; Berka, Noureddine

    2016-01-01

    Over one billion Muslims worldwide fast during the month of Ramadan. Ramadan fasting brings about some changes in the daily lives of practicing Muslims, especially in their diet and sleep patterns, which are associated with the risk of cardiovascular diseases. Over the years, many original studies have made the effort to identify the possible impact of the Ramadan fast on cardiovascular diseases. This systematic review and meta-analysis is an attempt to present the summary of key findings from those articles and an appraisal of selected literature. A systematic search using keywords of “;Ramadan fasting” and “;cardiovascular diseases” was conducted in primary research article and gray-literature repositories, in combination with hand searching and snow balling. Fifteen studies were finally selected for data extraction on the outcomes of stroke, myocardial infarction, and congestive heart failure. The analysis revealed that the incidence of cardiovascular events during the Ramadan fast was similar to the nonfasting period. Ramadan fast is not associated with any change in incidence of acute cardiovascular disease. PMID:27186152

  10. Two Types of Transpolar Arc Development, Event Studies with Data Set of ASTRID-2, DMSP, FAST, and SuperDARN

    NASA Technical Reports Server (NTRS)

    Narita, Yasuhito; Maezawa, Kiyoshi; Toshinori, Mukai; Kullen, A.; Ivchenko, N.; Marklund, G.; Frederick, R.; Carlson, C. W.; Spann, J. F.; Parks, G. K.; Six, N. Frank (Technical Monitor)

    2002-01-01

    Aurorae which appear in the polar cap are called transpolar arcs, polar cap arcs, sun-aligned arcs, or occasionally Theta-aurora because of its spatial distribution resembling Greek character 'Theta.' Morphology, IMF (Interplanetary Magnetic Field) relationship, and ionospheric convection patterns were studied in quest of mechanisms of transpolar arcs. Four events were analyzed: 1999/Jan/22/19:00 - 23/01:30 (1 event: a) 1999/Jan/24/06:00 - 10:00 (1 event: b) 1999/Feb/1 1/20:00 - 12/02:00 (2 events: c, d), with data set of ExB drift velocity data obtained by electric field measurements of ASTRID-2 and FAST, DMSP ion driftmeter data, and line-of-sight velocity data of SuperDARN. POLAR-UVI image data were used for spatial and temporal variations of transpolar arcs and ACE data set were used for investigation of IMF relationship. IMF-Bz was strongly positive (Bz from +8nT to +20 nT) during periods of all four transpolar arcs. In events (a),(b),(c), transpolar arcs appeared immediately after the direction of IMF turned northward, though IMF was fluctuating in event (b). A sudden increase of IMF-By, from +3nT to +18nT, was observed in event (d). Two different types of transpolar arc development were observed in POLAR-UVI: one which begins as a split from dawn or dusk sector of auroral oval and shifts poleward in event (a),(c),(d), and another which is initially a patch of auroral oval disturbed by substorm but develops as a transpolar arc, forming a growing finger-like shape from midnight sector (event b). Sunward flow, associated with positive IMF-Bz, were observed within newly-created polar caps in event (a),(c),(d). Not clear ionospheric convection pattern was seen across the polar cap arc in event (b) die to limitation of data set. In event (c), O+ with energy more than 1 keV were observed by FAST within a transpolar arc, suggesting that their origin be from plasma sheet. Transpolar arcs are thought to be projection of plasma sheet bifurcation into lobe regime. There

  11. Two Types of Transpolar Arc Development, Event Studies with Data Set of ASTRID-2, DMSP, FAST, and SuperDARN

    NASA Technical Reports Server (NTRS)

    Narita, Yasuhito; Maezawa, Kiyoshi; Toshinori, Mukai; Kullen, A.; Ivchenko, N.; Marklund, G.; Frederick, R.; Carlson, C. W.; Spann, J. F.; Parks, G. K.; hide

    2002-01-01

    Aurorae which appear in the polar cap are called transpolar arcs, polar cap arcs, sun-aligned arcs, or occasionally Theta-aurora because of its spatial distribution resembling Greek character 'Theta.' Morphology, IMF (Interplanetary Magnetic Field) relationship, and ionospheric convection patterns were studied in quest of mechanisms of transpolar arcs. Four events were analyzed: 1999/Jan/22/19:00 - 23/01:30 (1 event: a) 1999/Jan/24/06:00 - 10:00 (1 event: b) 1999/Feb/1 1/20:00 - 12/02:00 (2 events: c, d), with data set of ExB drift velocity data obtained by electric field measurements of ASTRID-2 and FAST, DMSP ion driftmeter data, and line-of-sight velocity data of SuperDARN. POLAR-UVI image data were used for spatial and temporal variations of transpolar arcs and ACE data set were used for investigation of IMF relationship. IMF-Bz was strongly positive (Bz from +8nT to +20 nT) during periods of all four transpolar arcs. In events (a),(b),(c), transpolar arcs appeared immediately after the direction of IMF turned northward, though IMF was fluctuating in event (b). A sudden increase of IMF-By, from +3nT to +18nT, was observed in event (d). Two different types of transpolar arc development were observed in POLAR-UVI: one which begins as a split from dawn or dusk sector of auroral oval and shifts poleward in event (a),(c),(d), and another which is initially a patch of auroral oval disturbed by substorm but develops as a transpolar arc, forming a growing finger-like shape from midnight sector (event b). Sunward flow, associated with positive IMF-Bz, were observed within newly-created polar caps in event (a),(c),(d). Not clear ionospheric convection pattern was seen across the polar cap arc in event (b) die to limitation of data set. In event (c), O+ with energy more than 1 keV were observed by FAST within a transpolar arc, suggesting that their origin be from plasma sheet. Transpolar arcs are thought to be projection of plasma sheet bifurcation into lobe regime. There

  12. Preliminary analysis on faint luminous lightning events recorded by multiple high speed cameras

    NASA Astrophysics Data System (ADS)

    Alves, J.; Saraiva, A. V.; Pinto, O.; Campos, L. Z.; Antunes, L.; Luz, E. S.; Medeiros, C.; Buzato, T. S.

    2013-12-01

    The objective of this work is the study of some faint luminous events produced by lightning flashes that were recorded simultaneously by multiple high-speed cameras during the previous RAMMER (Automated Multi-camera Network for Monitoring and Study of Lightning) campaigns. The RAMMER network is composed by three fixed cameras and one mobile color camera separated by, in average, distances of 13 kilometers. They were located in the Paraiba Valley (in the cities of São José dos Campos and Caçapava), SP, Brazil, arranged in a quadrilateral shape, centered in São José dos Campos region. This configuration allowed RAMMER to see a thunderstorm from different angles, registering the same lightning flashes simultaneously by multiple cameras. Each RAMMER sensor is composed by a triggering system and a Phantom high-speed camera version 9.1, which is set to operate at a frame rate of 2,500 frames per second with a lens Nikkor (model AF-S DX 18-55 mm 1:3.5 - 5.6 G in the stationary sensors, and a lens model AF-S ED 24 mm - 1:1.4 in the mobile sensor). All videos were GPS (Global Positioning System) time stamped. For this work we used a data set collected in four RAMMER manual operation days in the campaign of 2012 and 2013. On Feb. 18th the data set is composed by 15 flashes recorded by two cameras and 4 flashes recorded by three cameras. On Feb. 19th a total of 5 flashes was registered by two cameras and 1 flash registered by three cameras. On Feb. 22th we obtained 4 flashes registered by two cameras. Finally, in March 6th two cameras recorded 2 flashes. The analysis in this study proposes an evaluation methodology for faint luminous lightning events, such as continuing current. Problems in the temporal measurement of the continuing current can generate some imprecisions during the optical analysis, therefore this work aim to evaluate the effects of distance in this parameter with this preliminary data set. In the cases that include the color camera we analyzed the RGB

  13. Implications of electronic health record downtime: an analysis of patient safety event reports.

    PubMed

    Larsen, Ethan; Fong, Allan; Wernz, Christian; Ratwani, Raj M

    2017-05-30

    We sought to understand the types of clinical processes, such as image and medication ordering, that are disrupted during electronic health record (EHR) downtime periods by analyzing the narratives of patient safety event report data. From a database of 80 381 event reports, 76 reports were identified as explicitly describing a safety event associated with an EHR downtime period. These reports were analyzed and categorized based on a developed code book to identify the clinical processes that were impacted by downtime. We also examined whether downtime procedures were in place and followed. The reports were coded into categories related to their reported clinical process: Laboratory, Medication, Imaging, Registration, Patient Handoff, Documentation, History Viewing, Delay of Procedure, and General. A majority of reports (48.7%, n  = 37) were associated with lab orders and results, followed by medication ordering and administration (14.5%, n  = 11). Incidents commonly involved patient identification and communication of clinical information. A majority of reports (46%, n  = 35) indicated that downtime procedures either were not followed or were not in place. Only 27.6% of incidents ( n  = 21) indicated that downtime procedures were successfully executed. Patient safety report data offer a lens into EHR downtime-related safety hazards. Important areas of risk during EHR downtime periods were patient identification and communication of clinical information; these should be a focus of downtime procedure planning to reduce safety hazards. EHR downtime events pose patient safety hazards, and we highlight critical areas for downtime procedure improvement.

  14. Correlation of GIS Events 21 and 22 With the Asian Monsoon Record From Dongge Cave, and a Complete Record of Monsoon Variability Since the Penultimate Interglacial

    NASA Astrophysics Data System (ADS)

    Kelly, M. J.; Edwards, R. L.; Cheng, H.; Yuan, D.; Wang, Y.; Rowe, H.; Chen, Y.

    2006-12-01

    We present a new stalagmite record from Dongge Cave (southern China) between ~97 and 51 ka. The δ18O profile of stalagmite D11, which reflects intensity of the Asian Monsoon, fills a crucial gap in our Asian Monsoon time series during MIS 4 and the latter portion of MIS 5. Wang et al. (2001, Science 294, 2345-2348) have previously correlated last glacial period monsoon δ18O peaks at Hulu Cave (eastern China) with Greenland Interstadial events 1-20, and Kelly et al. (2006, Paleogeography, Palaeoclimatology, Palaeoecology 236, 20-38) made a similar correlation between δ18O peaks at Dongge Cave and GIS events 23 and 24. The new oxygen record contains monsoon features that correlate remarkably well with GIS 21 and 22. The ages of peak δ18O values for these two events are 82.6 ± 0.7 ka and 87.3 ± 0.7 ka, respectively. All of the last glacial GIS events now have analogous features in the monsoon record, thus allowing us to assign an absolute timescale to events recorded in Greenland ice. Our new data, combined with updated δ18O records from stalagmites D8 and D10, and previously reported data from both Hulu and Dongge Caves, now provides a continuous record of Asian Monsoon intensity since the penultimate interglacial. We are therefore able to make comparisons between the Asian Monsoon and other records of climate (sea level, atmospheric methane concentration, ice core records, etc.) during the full MIS 5 and MIS 7 interglacials, along with the transitions into and out of these interglacial periods.

  15. Digitized pressure-time records, selected nuclear events. Technical report, 1 September 1982-1 April 1986

    SciTech Connect

    McMullan, F.W.; Bryant, E.J.

    1986-04-30

    Pressure-time records are presented for selected atmospheric nuclear events. The records were extracted from published test reports, digitized, and given uniform pressure-time scales for a given event and a given range to permit easier comparison. Data include p-t, q-t, p(tot)-t, Mach No-t, and Impulse-t as appropriate. Selected data were scaled to 1 kT.

  16. Local vs. Global Processes in Chemostratigraphic Records from the Silurian Ireviken Event of Gotland, Sweden

    NASA Astrophysics Data System (ADS)

    Fike, D. A.; Rose, C. V.; Fischer, W. W.; Finnegan, S.

    2016-12-01

    Stratigraphic records of geochemical proxies (carbon isotopes, sulfur isotopes, iron speciation) are commonly used to reconstruct ancient global biogeochemical cycling and evaluate causal mechanisms of ecological and environmental change. However, the relationships linking proxy data in diagenetically stabilized sedimentary rocks to the environmental conditions under which they formed can be complex, filtered through a variety of depositional and diagenetic processes. Here we looked at a record of carbon and sulfur isotopic proxies preserved in Early Silurian (ca. 431 Ma) carbonate rocks from Gotland, Sweden. These strata record a ca. 4.5‰ positive excursion in the carbonate carbon isotopic composition (d13Ccarb). Associated with this isotopic shift is a biological turnover pulse known as the `Ireviken Event', which lasted ca. 1.0 Myr. The onset of the d13C excursion is associated with a shallowing-upward facies transition that has been suggested to reflect climate change (i.e. cooling). However, the relationships among environmental changes, faunal turnover, and carbon cycle perturbations remain enigmatic. These samples preserve parallel positive excursions of equal magnitude in both carbonate (d13Ccarb) and organic (d13Corg) carbon. In addition, the data reveal a synchronous perturbation in sulfur cycling, manifest as a ca. 7‰ positive excursion in the sulfur isotopic composition of carbonate-associated sulfate (d34SCAS) and a ca. 30‰ positive excursion in pyrite (δ34Spyr). The increase in δ34Spyr values is accompanied by a substantial, concomitant increase in stratigraphic variability of δ34Spyr. We discuss possible mechanisms (both local and global) that could give rise to these signals - and how we can use depositional and petrographic context to assess such varied scenarios. Considering these strata in their sequence stratigraphic context, these observations could be plausibly explained as recording real, but regional, changes in C and S cycling.

  17. Volcanic? Non-Volcanic? Low-Frequency Earthquakes beneath Osaka Bay - Event Search from Continuous Records -

    NASA Astrophysics Data System (ADS)

    Aso, N.; Ide, S.

    2010-12-01

    Low frequency earthquakes (LFEs) and tremors are observed in Nankai subduction zone, Japan. They are recognized to occur upon the subducting Philippine Sea plate. On the other hand, LEFs apart from plate boundary surface are also known (e.g. Ohmi and Obara, 2002). Most of them are distributed around volcanoes with some exceptions. Ones of the exceptions are LEFs occurring beneath Osaka Bay area between Kinki and Shikoku regions. These LFEs occur near the extension of tremor belt in Shikoku, and they are also close to the tear of Philippine Sea plate between Kinki and Shikoku regions (Ide et al., GRL in press). In addition, the epicenters of these LFEs are aligned toward north-northwest, the direction of the tear, and its extended line passes through the epicenter of the 1995 Kobe Earthquake. These facts suggest the hidden relations between LFEs, the subducting slab, and major inland earthquakes. The waveforms of the LFEs beneath Osaka Bay often have distinct spectral peak around 2Hz, unlike LFEs in subduction zones. This feature is common to some volcanic tremors. It is also suggested that mantle-derived water is blowing off along the wake of the slab tear, and some fluid likely exists beneath Osaka Bay. The LFEs have been detected by routine analysis of the Japan Meteorological Agency (JMA). These are small portion of overall activities, because the routine analysis is not optimized to detect small low frequency events in noisy data. To figure out whole activities of LFEs, we apply Matched Filter Analysis (Gibbons and Ringdal, 2006; Shelly et al., 2007) to continuous waveform records, using LFEs detected by JMA as template events. We used the 69 components in the 23 stations in Hi-net, maintained by the National Reserch Institute for Earth Science and Disaster Prevention. The waveforms are bandpass filtered between 2 and 8Hz. We calculated the cross-correlations of template LFEs and continuous records with 8s time window. An LFE is detected when the cross

  18. Parametric Dependence Of Fast-ion Transport Events On The National Spherical Torus Experiment

    SciTech Connect

    Fredrickson, Erik; Gorelenkov, N. N.; Podesta, M.; Gerhardt, S. P.; Bell, R. E.; Diallo, A.; LeBlanc, B.; Bortolon, A.

    2014-03-31

    Neutral-beam heated tokamak plasmas commonly have more than one third of the plasma kinetic energy in the non-thermal energetic beam ion population. This population of fast ions heats the plasma, provides some of the current drive, and can affect the stability (positively or negatively) of magnetohydrodynamic instabilities. This population of energetic ions is not in thermodynamic equilibrium, thus there is free-energy available to drive instabilities, which may lead to redistribution of the fast ion population. Understanding under what conditions beam-driven instabilities arise, and the extent of the resulting perturbation to the fast ion population, is important for predicting and eventually demonstrating non-inductive current ramp-up and sustainment in NSTX-U, as well as the performance of future fusion plasma experiments such as ITER. This paper presents an empirical approach towards characterizing the stability boundaries for some common energetic-ion-driven instabilities seen on NSTX.

  19. Mid-Cretaceous carbon cycle perturbations and Oceanic Anoxic Events recorded in southern Tibet

    PubMed Central

    Zhang, Xiaolin; Chen, Kefan; Hu, Dongping; Sha, Jingeng

    2016-01-01

    The organic carbon isotope (δ13Corg) curve for ~1.7-km-thick mid-Cretaceous strata of the Chaqiela section in Gamba area, southern Tibet is presented in this study. C-isotopic chemostratigraphic correlation combined with biostratigraphic constraints show that the Chaqiela section spans early Aptian through early Campanian period, and that almost all of the carbon cycle perturbations and Oceanic Anoxic Events during the mid-Cretaceous period are well recorded in the continental margin area of the southeastern Tethys Ocean. Significantly, two levels of methane-derived authigenic carbonates were identified at the onset of OAE1b near the Aptian-Albian boundary. We suggest that an increase in methane release from gas hydrates, potentially driven by sea-level fall and bottom water temperature increase, may have contributed to the large negative δ13Corg excursions and global warming during OAE1b. PMID:28000797

  20. Mid-Cretaceous carbon cycle perturbations and Oceanic Anoxic Events recorded in southern Tibet.

    PubMed

    Zhang, Xiaolin; Chen, Kefan; Hu, Dongping; Sha, Jingeng

    2016-12-21

    The organic carbon isotope (δ(13)Corg) curve for ~1.7-km-thick mid-Cretaceous strata of the Chaqiela section in Gamba area, southern Tibet is presented in this study. C-isotopic chemostratigraphic correlation combined with biostratigraphic constraints show that the Chaqiela section spans early Aptian through early Campanian period, and that almost all of the carbon cycle perturbations and Oceanic Anoxic Events during the mid-Cretaceous period are well recorded in the continental margin area of the southeastern Tethys Ocean. Significantly, two levels of methane-derived authigenic carbonates were identified at the onset of OAE1b near the Aptian-Albian boundary. We suggest that an increase in methane release from gas hydrates, potentially driven by sea-level fall and bottom water temperature increase, may have contributed to the large negative δ(13)Corg excursions and global warming during OAE1b.

  1. Mid-Cretaceous carbon cycle perturbations and Oceanic Anoxic Events recorded in southern Tibet

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaolin; Chen, Kefan; Hu, Dongping; Sha, Jingeng

    2016-12-01

    The organic carbon isotope (δ13Corg) curve for ~1.7-km-thick mid-Cretaceous strata of the Chaqiela section in Gamba area, southern Tibet is presented in this study. C-isotopic chemostratigraphic correlation combined with biostratigraphic constraints show that the Chaqiela section spans early Aptian through early Campanian period, and that almost all of the carbon cycle perturbations and Oceanic Anoxic Events during the mid-Cretaceous period are well recorded in the continental margin area of the southeastern Tethys Ocean. Significantly, two levels of methane-derived authigenic carbonates were identified at the onset of OAE1b near the Aptian-Albian boundary. We suggest that an increase in methane release from gas hydrates, potentially driven by sea-level fall and bottom water temperature increase, may have contributed to the large negative δ13Corg excursions and global warming during OAE1b.

  2. Decoupling biogeochemical records, extinction, and environmental change during the Cambrian SPICE event.

    PubMed

    Schiffbauer, James D; Huntley, John Warren; Fike, David A; Jeffrey, Matthew Jarrell; Gregg, Jay M; Shelton, Kevin L

    2017-03-01

    Several positive carbon isotope excursions in Lower Paleozoic rocks, including the prominent Upper Cambrian Steptoean Positive Carbon Isotope Excursion (SPICE), are thought to reflect intermittent perturbations in the hydrosphere-biosphere system. Models explaining these secular changes are abundant, but the synchronicity and regional variation of the isotope signals are not well understood. Examination of cores across a paleodepth gradient in the Upper Cambrian central Missouri intrashelf basin (United States) reveals a time-transgressive, facies-dependent nature of the SPICE. Although the SPICE event may be a global signal, the manner in which it is recorded in rocks should and does vary as a function of facies and carbonate platform geometry. We call for a paradigm shift to better constrain facies, stratigraphic, and biostratigraphic architecture and to apply these observations to the variability in magnitude, stratigraphic extent, and timing of the SPICE signal, as well as other biogeochemical perturbations, to elucidate the complex processes driving the ocean-carbonate system.

  3. Predictors of Arrhythmic Events Detected by Implantable Loop Recorders in Renal Transplant Candidates

    PubMed Central

    Silva, Rodrigo Tavares; Martinelli Filho, Martino; Peixoto, Giselle de Lima; de Lima, José Jayme Galvão; de Siqueira, Sérgio Freitas; Costa, Roberto; Gowdak, Luís Henrique Wolff; de Paula, Flávio Jota; Kalil Filho, Roberto; Ramires, José Antônio Franchini

    2015-01-01

    Background The recording of arrhythmic events (AE) in renal transplant candidates (RTCs) undergoing dialysis is limited by conventional electrocardiography. However, continuous cardiac rhythm monitoring seems to be more appropriate due to automatic detection of arrhythmia, but this method has not been used. Objective We aimed to investigate the incidence and predictors of AE in RTCs using an implantable loop recorder (ILR). Methods A prospective observational study conducted from June 2009 to January 2011 included 100 consecutive ambulatory RTCs who underwent ILR and were followed-up for at least 1 year. Multivariate logistic regression was applied to define predictors of AE. Results During a mean follow-up of 424 ± 127 days, AE could be detected in 98% of patients, and 92% had more than one type of arrhythmia, with most considered potentially not serious. Sustained atrial tachycardia and atrial fibrillation occurred in 7% and 13% of patients, respectively, and bradyarrhythmia and non-sustained or sustained ventricular tachycardia (VT) occurred in 25% and 57%, respectively. There were 18 deaths, of which 7 were sudden cardiac events: 3 bradyarrhythmias, 1 ventricular fibrillation, 1 myocardial infarction, and 2 undetermined. The presence of a long QTc (odds ratio [OR] = 7.28; 95% confidence interval [CI], 2.01–26.35; p = 0.002), and the duration of the PR interval (OR = 1.05; 95% CI, 1.02–1.08; p < 0.001) were independently associated with bradyarrhythmias. Left ventricular dilatation (LVD) was independently associated with non-sustained VT (OR = 2.83; 95% CI, 1.01–7.96; p = 0.041). Conclusions In medium-term follow-up of RTCs, ILR helped detect a high incidence of AE, most of which did not have clinical relevance. The PR interval and presence of long QTc were predictive of bradyarrhythmias, whereas LVD was predictive of non-sustained VT. PMID:26351983

  4. The record precipitation and flood event in Iberia in December 1876: description and synoptic analysis

    NASA Astrophysics Data System (ADS)

    Trigo, Ricardo; Varino, Filipa; Ramos, Alexandre; Valente, Maria; Zêzere, José; Vaquero, José; Gouveia, Célia; Russo, Ana

    2014-04-01

    The first week of December 1876 was marked by extreme weather conditions that affected the south-western sector of the Iberian Peninsula, leading to an all-time record flow in two large international rivers. As a direct consequence, several Portuguese and Spanish towns and villages located in the banks of both rivers suffered serious flood damage on 7 December 1876. These unusual floods were amplified by the preceding particularly autumn wet months, with October 1876 presenting extremely high precipitation anomalies for all western Iberia stations. Two recently digitised stations in Portugal (Lisbon and Evora), present a peak value on 5 December 1876. Furthermore, the values of precipitation registered between 28 November and 7 December were so remarkable that, the episode of 1876 still corresponds to the maximum average daily precipitation values for temporal scales between 2 and 10 days. Using several different data sources, such as historical newspapers of that time, meteorological data recently digitised from several stations in Portugal and Spain and the recently available 20th Century Reanalysis, we provide a detailed analysis on the socio-economic impacts, precipitation values and the atmospheric circulation conditions associated with this event. The atmospheric circulation during these months was assessed at the monthly, daily and sub-daily scales. All months considered present an intense negative NAO index value, with November 1876 corresponding to the lowest NAO value on record since 1865. We have also computed a multivariable analysis of surface and upper air fields in order to provide some enlightening into the evolution of the synoptic conditions in the week prior to the floods. These events resulted from the continuous pouring of precipitation registered between 28 November and 7 December, due to the consecutive passage of Atlantic low-pressure systems fuelled by the presence of an atmospheric-river tropical moisture flow over central Atlantic Ocean.

  5. Preliminary Record of Holocene Storm Events in the Finger Lakes, NY

    NASA Astrophysics Data System (ADS)

    Curtin, T. M.; Morgan, C. K.; Petrick, B. F.; Davin, L. I.; Rogers, C. E.; Crocker, M. L.; Loddengaard, K.; Baker, A. P.

    2006-12-01

    Terrigenous sediment deposited in three of the Finger Lakes of New York, Seneca, Keuka, and Canandaigua, preserve evidence for major storm events over the past ~13 ka. A combination of analytical techniques was used for ten cores, including visual inspection, magnetic susceptibility, loss-on-ignition, and grain size to identify these storm events. Storm layers are characterized by coincident coarse siliciclastic mean grain size, high % sand content, and more terrestrial plant macrofossils than the surrounding mud. The combination of sedimentological analyses with radiocarbon dating allows for development of a paleostorm chronology for each lake and comparison of the timing of the storm layers to determine if they were deposited synchronously or not. The number (10-31), thickness (0.1-6 cm), and grain size characteristics (1-37% sand) of the layers present in each core varies widely. As a result, single storm-related event deposition does not appear to have been synchronous among the three lake basins. However, there is temporal clustering of events. The greatest number of storm layers occurs in two distinct intervals, between ~13 and ~8.2 ka and ~4.6 and 0 ka. During the early to mid-Holocene, the number of events was high. We infer that a period of increased storminess occurred when the average climate of the region became warmer and wetter. Between ~8.2 and ~4.6 ka, when the average climate in North America was warm and dry, the number, thickness, and average mean grain size of the terrigenous layers decreased. After ~4.6 ka, the number of storms appears to have gradually increased as a result of a shift in the southern extent of the jet stream. The thickest, sandiest layers were deposited beginning at ~700 yrs BP and is associated with the climate of the Little Ice Age and Medieval Warming Period. The increase in the number, thickness, and sand content is especially apparent at ~290 yrs BP and is coincident the onset of widespread erosion due to deforestation

  6. Applying a New Event Detection Algorithm to an Ocean Bottom Seismometer Dataset Recorded Offshore Southern California

    NASA Astrophysics Data System (ADS)

    Bishop, J.; Kohler, M. D.; Bunn, J.; Chandy, K. M.

    2015-12-01

    A number of active southern California offshore faults are capable of M>6 earthquakes, and the only permanent Southern California Seismic Network stations that can contribute to ongoing, small-magnitude earthquake detection and location are those located on the coastline and islands. To obtain a more detailed picture of the seismicity of the region, an array of 34 ocean bottom seismometers (OBSs) was deployed to record continuous waveform data off the coast of Southern California for 12 months (2010-2011) as part of the ALBACORE (Asthenospheric and Lithospheric Broadband Architecture from the California Offshore Region Experiment) project. To obtain a local event catalog based on OBS data, we make use of a newly developed data processing platform based on Python. The data processing procedure comprises a multi-step analysis that starts with the identification of significant signals above the time-adjusted noise floor for each sensor. This is followed by a time-dependent statistical estimate of the likelihood of an earthquake based on the aggregated signals in the array. For periods with elevated event likelihood, an adaptive grid-fitting procedure is used that yields candidate earthquake hypocenters with confidence estimates that best match the observed sensor signals. The results are validated with synthetic travel times and manual picks. Using results from ALBACORE, we have created a more complete view of active faulting in the California Borderland.

  7. Calculations of the FLAX events with comparisons to particle velocity data recorded at low stress

    SciTech Connect

    Rambo, J.

    1993-09-01

    The FLAX event, fired in 1972, produced two particle velocity data sets from two devices in the same hole, U2dj. The data are of interest because they contain verification of focusing of a shock wave above the water table. The FLAX data show the peak velocity attenuation from the device buried in saturated tuff are different from those emanating from the upper device buried in porous alluvium. The attenuations of the peaks are different in regions traversed by both waves traveling at the same sound speed and measured by the same particle velocity gages. The attenuation rate from the lower device is due to 2-D effects attributed to wave focusing above the water table and is a feature that should be captured by 2-D calculations. LLNL`s KDYNA calculations used for containment analyses have utilized a material model initially developed by Butkovich, which estimates strength and compressibility based on gas porosity, total porosity, and water content determined from geophysical measurements. Unfortunately, the material model estimates do not correctly model the more important details of strength and compressibility used for matching the velocity data. The velocity gage data contain information that can be related to the strength properties of the medium, provided that there are more than two gages recording in the stress region of plastic deformation of the material. A modification to Butkovich`s model incorporated approximate strengths derived from the data. The mechanisms of focusing will be discussed and will incorporate additional information from the TYBO event.

  8. Construction and laboratory test of a fibre optic sensor for rotational events recording

    NASA Astrophysics Data System (ADS)

    Kurzych, Anna; Krajewski, Zbigniew; Kowalski, Jerzy K.; Jaroszewicz, Leszek R.

    2016-05-01

    We present a novel and technically advanced system - Fibre-Optic System for Rotational Events & Phenomena Monitoring (FOSREM). It has been designed in order to register and monitor rotational events in seismological observatories, engineering constructions, mines and even on glaciers and in their vicinity. Its wide application field is a result of unique parameters and electronic solutions which give an opportunity to measure a component of rotation in the wide range of a signal amplitude from 10-8 rad/s to 10 rad/s, as well as a frequency from 0 Hz to the upper frequency between 2.56 Hz to 328.12 Hz. Moreover, the numerical analysis and simulations indicate that it keeps the theoretical sensitivity equal to 2·10-8 rad/s/Hz1/2. FOSREM is equipped with an advanced communication module which gives the possibility for a remote detection parameter control, as well as the recorded data receiving. It enables the sensor to assemble in any chosen place. In the paper we present laboratory investigations and tests which confirm the wide application field and practical aspects of FOSREM.

  9. Iridium abundance measurements across bio-event horizons in the geological record

    NASA Technical Reports Server (NTRS)

    Orth, C. J.; Attrep, M., Jr.

    1988-01-01

    Geochemical studies have been performed on thousands of rock samples collected across bio-event horizons in the fossil record using INAA for about 40 common and trace elements and radiochemical isolation procedures for Os, Ir, Pt, and Au on selected samples. These studies were begun soon after the Alvarez team announced their discovery of the Cretaceous-Tertiary (K-T) Ir anomaly in marine rock sequences in Europe. With their encouragement the Authors searched for the anomaly in nearby continental (freshwater coal swamp) deposits. In collaboration with scientists from the U.S.G.S. in Denver, the anomaly was located and it was observed that a floral crisis occurred at the same stratigraphic position as the Ir spike. Further work in the Raton Basin has turned up numerous well-preserved K-T boundary sections. Although the Authors have continued to study the K-T boundary and provide geochemical measurements for other groups trying to precisely locate it, the primary effort was turned to examining the other bio-events in the Phanerozoic, especially to those that are older than the terminal Cretaceous. A list of horizons that were examined in collaboration with paleontologists and geologists is given. Results are also given and discussed.

  10. Normal modes from the 2013 Sea of Okhotsk earthquake, the largest deep event ever recorded

    NASA Astrophysics Data System (ADS)

    Okal, E. A.

    2013-12-01

    With a moment of 4.1 10**28 dyn*cm, the Sea of Okhotsk earthquake of 24 May 2013 is the largest deep event ever recorded. This provides a unique opportunity to study the excitation of low-frequency normal modes, including overtone and radial ones. The principal questions addressed will be the possible existence of a slow component to the source, which is not warranted by preliminary results; and the possible presence of an isotropic component to the moment tensor of its source. The latter was strongly debated in the case of the 1970 Colombian event (Gilbert and Dziewonski, 1973; Okal and Geller, 1979), and clearly found absent from the source of the 1994 Bolivian one (Kikuchi and Kanamori, 1994; Okal, 1996). Critical in this respect will be the investigation of the relative excitation of the the radial modes, and in particular, the fundamental 0s0, for which a sufficiently long (90 days) time series was not available by the submission deadline.

  11. Evaluation of Advanced Air Bag Deployment Algorithm Performance using Event Data Recorders

    PubMed Central

    Gabler, Hampton C.; Hinch, John

    2008-01-01

    This paper characterizes the field performance of occupant restraint systems designed with advanced air bag features including those specified in the US Federal Motor Vehicle Safety Standard (FMVSS) No. 208 for advanced air bags, through the use of Event Data Recorders (EDRs). Although advanced restraint systems have been extensively tested in the laboratory, we are only beginning to understand the performance of these systems in the field. Because EDRs record many of the inputs to the advanced air bag control module, these devices can provide unique insights into the characteristics of field performance of air bags. The study was based on 164 advanced air bag cases extracted from NASS/CDS 2002-2006 with associated EDR data. In this dataset, advanced driver air bags were observed to deploy with a 50% probability at a longitudinal delta-V of 9 mph for the first stage, and at 26 mph for both inflator stages. In general, advanced air bag performance was as expected, however, the study identified cases of air bag deployments at delta-Vs as low as 3-4 mph, non-deployments at delta-Vs over 26 mph, and possible delayed air bag deployments. PMID:19026234

  12. Characterization of seizure-like events recorded in vivo in a mouse model of Rett syndrome.

    PubMed

    Colic, Sinisa; Wither, Robert G; Zhang, Liang; Eubanks, James H; Bardakjian, Berj L

    2013-10-01

    Rett syndrome is a neurodevelopmental disorder caused by mutations in the X-linked gene encoding methyl-CpG-binding protein 2 (MECP2). Spontaneous recurrent discharge episodes are displayed in Rett-related seizures as in other types of epilepsies. The aim of this paper is to investigate the seizure-like event (SLE) and inter-SLE states in a female MeCP2-deficient mouse model of Rett syndrome and compare them to those found in other spontaneous recurrent epilepsy models. The study was performed on a small population of female MeCP2-deficient mice using telemetric local field potential (LFP) recordings over a 24 h period. Durations of SLEs and inter-SLEs were extracted using a rule-based automated SLE detection system for both daytime and nighttime, as well as high and low power levels of the delta frequency range (0.5-4 Hz) of the recorded LFPs. The results suggest SLE occurrences are not influenced by circadian rhythms, but had a significantly greater association with delta power. Investigating inter-SLE and SLE states by fitting duration histograms to the gamma distribution showed that SLE initiation and termination were associated with random and deterministic mechanisms, respectively. These findings when compared to reported studies on epilepsy suggest that Rett-related seizures share many similarities with absence epilepsy.

  13. A High-Resolution Porphyrin Nitrogen Isotope Record of an Oceanic Anoxic Event

    NASA Astrophysics Data System (ADS)

    Pearson, A.; Higgins, M. B.; Robinson, R. S.; Carter, S. J.

    2010-12-01

    Nitrogen isotope values measured in sediments deposited at times of widespread marine suboxic conditions are consistently more depleted in 15N than are modern marine sediments. We measured a high-resolution δ15N record of sedimentary porphyrins from a section spanning the Cenomanian-Turonian Oceanic Anoxic Event (OAE) II to examine changes in the nitrogen cycle recorded in surface waters. We compare these values to δ15N values of three sedimentary fractions: bulk sediment, extractable organic matter (bitumen), and non-extractable organic matter (kerogen). All fractions record similar trends; are offset from each other by consistent differences that are reflective of algal (not cyanobacterial) export; and are depleted in 15N compared to modern sedimentary samples, both before, during, and after the interval defined by the OAE. Prior to the termination of OAE II, there is a slight further negative excursion in δ15N values. In order to interpret these and other depleted δ15N values measured in similar black shales, we invoke a nitrogen isotope model that considers the importance of redox transformations of N under suboxic conditions. This model invokes an ocean in which the deep N reservoir is dominated by NH4+, limited nitrification occurs in the photic zone, and chemocline denitrification acts as a quantitative sink for downwelling nitrate. Although in this model a large component of net production may be fueled by N fixation, N fixation alone cannot generate biomass with δ15N values as depleted as are seen in many Mesozoic OAE sections. We postulate that throughout the Phanerozoic, excursions leading to negative values of d15N reflect relatively low rates of nitrosification relative to the sum of NH4+ utilization and N fixation.

  14. Genomic inferences of domestication events are corroborated by written records in Brassica rapa.

    PubMed

    Qi, Xinshuai; An, Hong; Ragsdale, Aaron P; Hall, Tara E; Gutenkunst, Ryan N; Chris Pires, J; Barker, Michael S

    2017-07-01

    Demographic modelling is often used with population genomic data to infer the relationships and ages among populations. However, relatively few analyses are able to validate these inferences with independent data. Here, we leverage written records that describe distinct Brassica rapa crops to corroborate demographic models of domestication. Brassica rapa crops are renowned for their outstanding morphological diversity, but the relationships and order of domestication remain unclear. We generated genomewide SNPs from 126 accessions collected globally using high-throughput transcriptome data. Analyses of more than 31,000 SNPs across the B. rapa genome revealed evidence for five distinct genetic groups and supported a European-Central Asian origin of B. rapa crops. Our results supported the traditionally recognized South Asian and East Asian B. rapa groups with evidence that pak choi, Chinese cabbage and yellow sarson are likely monophyletic groups. In contrast, the oil-type B. rapa subsp. oleifera and brown sarson were polyphyletic. We also found no evidence to support the contention that rapini is the wild type or the earliest domesticated subspecies of B. rapa. Demographic analyses suggested that B. rapa was introduced to Asia 2,400-4,100 years ago, and that Chinese cabbage originated 1,200-2,100 years ago via admixture of pak choi and European-Central Asian B. rapa. We also inferred significantly different levels of founder effect among the B. rapa subspecies. Written records from antiquity that document these crops are consistent with these inferences. The concordance between our age estimates of domestication events with historical records provides unique support for our demographic inferences. © 2017 John Wiley & Sons Ltd.

  15. Spectroscopic interpretation and velocimetry analysis of fluctuations in a cylindrical plasma recorded by a fast camera

    SciTech Connect

    Oldenbuerger, S.; Brandt, C.; Brochard, F.; Lemoine, N.; Bonhomme, G.

    2010-06-15

    Fast visible imaging is used on a cylindrical magnetized argon plasma produced by thermionic discharge in the Mirabelle device. To link the information collected with the camera to a physical quantity, fast camera movies of plasma structures are compared to Langmuir probe measurements. High correlation is found between light fluctuations and plasma density fluctuations. Contributions from neutral argon and ionized argon to the overall light intensity are separated by using interference filters and a light intensifier. Light emitting transitions are shown to involve a metastable neutral argon state that can be excited by thermal plasma electrons, thus explaining the good correlation between light and density fluctuations. The propagation velocity of plasma structures is calculated by adapting velocimetry methods to the fast camera movies. The resulting estimates of instantaneous propagation velocity are in agreement with former experiments. The computation of mean velocities is discussed.

  16. A survey of the cusp ion outflow's kinetic energy flux measured by Polar and FAST during conjunction events

    NASA Astrophysics Data System (ADS)

    Tian, S.; Wygant, J. R.; Cattell, C. A.; Scudder, J. D.; McFadden, J. P.; Mozer, F.; Russell, C. T.

    2014-12-01

    Polar and FAST conjunction events are selected from Polar cusp crossings in 1997. These conjunction events reveal a common pattern in which Polar observed significant ion kinetic energy flux in the upward direction at mid-altitudes (below 6 Re). Depending on the magnetic activity level, the maximum ion kinetic energy flux is on the order of 10-100 mW/m^2, when mapped to the ionosphere. It is an order of magnitude or more larger than the ion kinetic energy flux observed by FAST in conjunction at altitudes of <1 Re. Therefore, the ion outflows are significantly energized within the mid-latitude cusp. Also shown in the conjunction events is that the downward Poynting flux has enough wave energy to power the ion energization. The observed pattern suggests that the cusp at ionosphere altitudes is not a simple mapping of higher altitude particles. Instead, the mid-latitude cusp receives significant downward Poynting flux from higher altitude due to the solar wind/magnetosphere coupling. Within the mid-altitude cusp, the Poynting flux then supplies energy to power the ionosphere/magnetosphere coupling. Ion outflows are triggered and energized, forming a planetary wind that feeds the magnetosphere with ionospheric ions. During southward IMF, the wind convects anti-sunward and can affect the tail lobe, the nightside auroral region and the nightside plasma sheet.

  17. Comparison of Offshore Turbidite records and Lake Disturbance Events at the Latitude of Seattle, Washington

    NASA Astrophysics Data System (ADS)

    Galer, S.; Goldfinger, C.; Morey, A. E.; Black, B.; Romsos, C.; Beeson, J. W.; Erhardt, M.

    2014-12-01

    We are investigating the paleoseismic history of northern Washington using offshore turbidite cores and lake sediments collected from forearc lakes along a transect from offshore to Seattle, Washington. Additional offshore cores, ash determinations and heavy mineral analysis flesh out the turbidite stratigraphy off northern Washington, and support 3-5 proximal turbidites in northern Washington canyons (see Adams, 1990) in addition to the 19 regionally correlated beds. Onshore, we have cored multiple lakes including (west to east) Beaver, Leland, Tarboo, Hall, Sawyer, and Wapato, east of the Cascades, and collected multibeam bathymetry, backscatter and chirp subbottom data. These lakes are small (2-113 ha), 6-18 m deep, and are all kettle lakes except Beaver Lake (landslide-dammed) and Wapato Lake, a glacial scour. These lakes were selected for their limited outside sediment sources and low sensitivity to ground shaking. The sedimentology is mostly organic-rich gyttja. All lakes contain the Mazama ash based on its similar depth occurrence in previously published cores and new EMP analysis. Computed Tomography (CT) density, gamma density, and magnetic susceptibility (ms) data show there is more stratigraphic variability than is visually apparent. Low-energy disturbance events are apparent in the stratigraphy of all lakes (except Hall) as increases in clastics, density, and ms. The number of post Mazama disturbance events is similar to the number of expected great earthquakes found offshore and onshore, though definition of the boundaries of the lake events is much less clear. Initial radiocarbon results and preliminary correlations along this 185 km transect show strong similarities in stratigraphic records between these cores over the past ~7600 years, anchored by the Mazama tephra. Preliminary comparisons with offshore cores show a striking similarity in downcore variability in physical properties. Given the evidence for earthquake origin for the offshore cores

  18. Danngarrd-Oscar events recorded in a terrestrial sequence in central British Columbia, Canada

    NASA Astrophysics Data System (ADS)

    Ward, B. C.; Geertsema, M.; Telka, A.; Mathewes, R.

    2012-12-01

    Danngarrd-Oscar events recorded in the GISP2 Greenland Ice Core. The increasingly dry and cold conditions indicated by the macrofossil assemblage likely reflect the growth of ice in the Coast Mountains that would reduce the availability of moisture to the Interior Plateau from Pacific air masses. This is confirmed by reconstruction of the growth of the Cordilleran Ice Sheet during the Late Wisconsinan based on published radiocarbon dates.

  19. Fast transient absorption spectroscopy of the early events in photoexcited chiral benzophenone naphthalene dyads

    NASA Astrophysics Data System (ADS)

    Perez-Ruiz, Raul; Groeneveld, Michiel; van Stokkum, Ivo H. M.; Tormos, Rosa; Williams, René M.; Miranda, Miguel A.

    2006-09-01

    Photoinduced intra-molecular energy transfer in two ketoprofen(KP)-naproxol(NPX) diastereomers proceeds via two pathways. Very fast singlet-triplet energy transfer ( k = 1.2 × 10 11 s -1) from KP to NPX occurs for a small percentage (6%) and the major pathway is triplet-triplet energy transfer ( k ˜ 3 × 10 9 s -1). This was shown with femtosecond transient absorption spectroscopy and global and target analysis. Whereas the NPX triplet decay is strongly stereospecific (ratio of 1.6), the NPX triplet state formation for both dyads is very similar (ratio of 1 for the fast process and 1.2 for the slower process).

  20. Proposed design for a fast (parallel) preprocessor for the spin spectrometer and other eventful albatrosses

    SciTech Connect

    Hensley, D.C.

    1981-01-01

    Because devices like the Spin Spectrometer described in a previous paper to this conference can produce an extremely fast but fairly simple-to-process data stream, it seems reasonable to consider front-end preprocessors having special characteristics. In general, the kinds of transformations being considered do not require floating point calculations or extensive calculations. In order to be somewhat specific, the particular data acquisition/processing problems posed by the Spin Spectrometer at the Holifield Heavy Ion Facility will be discussed.

  1. A Comparison of Reliability Measures for Continuous and Discontinuous Recording Methods: Inflated Agreement Scores with Partial Interval Recording and Momentary Time Sampling for Duration Events

    ERIC Educational Resources Information Center

    Rapp, John T.; Carroll, Regina A.; Stangeland, Lindsay; Swanson, Greg; Higgins, William J.

    2011-01-01

    The authors evaluated the extent to which interobserver agreement (IOA) scores, using the block-by-block method for events scored with continuous duration recording (CDR), were higher when the data from the same sessions were converted to discontinuous methods. Sessions with IOA scores of 89% or less with CDR were rescored using 10-s partial…

  2. 232Th-228Ra-228Th Recording of Estuarine and Coastal Sedimentological Events

    NASA Astrophysics Data System (ADS)

    Hillaire-Marcel, C.; Ghaleb, B.; Ruiz-Fernandez, A.

    2011-12-01

    Climatic events (e.g., storminess, floods) and river/coastal management activities (e.g., dredging) may result in the removal and re-suspension of contaminated sediments in shallow coastal areas and estuaries, thus leading to long-term contamination of such environments. Short-lived daughter isotopes of 232Th (228Ra-228Th) in sediments may then provide some quantitative assessment of the amount of material removed/re-deposited as well as some indications on the chronology of causal events. Examples from the Gulf of St. Lawrence (GSL) and the Pacific coastal rea of Mexico (PcM) are used to illustrate such isotopic responses to natural or anthropogenic disturbances. In the GSL relatively steady accumulation processes are usually observed, although sedimentary sequences show variable benthic mixing patterns over a large array of sedimentation rates (from mm/a to cm/a). In undisturbed sequences, 232Th-daughter isotopes in particulate matter show strong disequilibria due i) to 228Ra-diffusion/228Th adsorption in source-soils and during particulate transport, ii) 228Ra-behavior at the water column/sea-floor interface. Core-top sediments thus depict a strong excess in 228Th vs. 232Th. Below, a fast return (within ~ 10 a) of 228Th to equilibrium with its parent 228Ra leads to a 228Th deficit vs 232Th, in response to 228Ra-losses and diffusion towards the water column. Deeper, a return to full equilibrium conditions is observed (~ 30 a), but for "non-local mixing" events. Few disturbances are observed in the area. They include nearly cyclic pulses in 210Pb at the head of the Laurentian Trough, which we attribute to dredging operations of the St. Lawrence Sea-Way, and in the sealing of Hg-contaminated sediments in the Saguenay Fjord, by flood layers. Comparatively most sequences cored in estuarine settings of the PcM illustrate more critical situations with respect to the re-suspension of sediments, which are often contaminated due to land management and industrial practices

  3. The 8.2 kyr event recorded at high resolution by a speleothem from the Northern French Alps

    NASA Astrophysics Data System (ADS)

    Couchoud, Isabelle; Drysdale, Russell; Hellstrom, John; Perrette, Yves

    2016-04-01

    Continental records of Holocene climate variability in the Alps are scarce and they rarely document the "8.2 kyr event". Several reasons have been proposed: records do not have sufficient resolution, are not precisely dated or the proxies are not sufficiently sensitive to climate variations associated with this event. The European records of adequate resolution generally allow the identification of an anomaly but its characterisation is unclear: it seems that the event has triggered significant impacts only for a few decades and mainly expressed in winter (whereas most archives are more sensitive to summer conditions). Thus, the detailed characterisation of the impacts of this event requires records with sub-annual resolution and preferably sensitive to winter conditions. Here we present a multi-proxy, high-resolution analysis of this event, as recorded by a stalagmite of the Bauges massif (Northern French Alps), at ~1400 m altitude. Comparison of these results with other regional and distant data allows for a discussion about climatic impacts and teleconnections at this time.

  4. Regionality of record-breaking low temperature events in China and its associated circulation

    NASA Astrophysics Data System (ADS)

    Kuang, Xueyuan; Zhang, Yaocun; Huang, Danqing; Huang, Ying

    2016-03-01

    Extreme cold events frequently occur around the world in recent several years and arouse widespread concern. In this study, 17 record-breaking event processes (RBEPs) of low temperature during 1981-2012 are identified by using daily minimum temperature at 1897 meteorological stations in China. These RBEPs are classified into two types based on the occurring area at northern or southern China to compositely examine the associated circulations. Although the correspondence between Arctic oscillation (AO) and RBEPs is not linearly stable, there still exist relationship between them, i.e. under AO negative phase the RBEPs tend to occur at northern China, nor the southern part, where the RBEPs prefer to happen under AO positive phase. In the RBEPs occurring at southern China, the continent high pressure over Mongolia area is extremely intensified and the East Asian polar front jet stream is enhanced accompanied with strong synoptic-scale eddy kinetic energy transports. Correspondingly, the cold air masses break out and unobstructed southward intrude to low latitudes, causing severe cooling effect in southern China. In the RBEPs occurring at northern China, however, the extremely intensified high pressure over northern Siberian area, combining with the northward enhanced subtropical jet stream, lead to the cold air mass accumulation and blockage at mid-latitudes and therefore RBEPs of low temperature at this area. Further study implies that interdecadal change of the AO phase and differences of synoptic-scale eddy activity might synthetically attribute to the different regional preference of those RBEPs of low temperature that are mostly located at southern China in 1990s but concentrated in northern China in 2000s.

  5. Predicting Major Adverse Kidney Events among Critically Ill Adults Using the Electronic Health Record.

    PubMed

    McKown, Andrew C; Wang, Li; Wanderer, Jonathan P; Ehrenfeld, Jesse; Rice, Todd W; Bernard, Gordon R; Semler, Matthew W

    2017-08-31

    Prediction of major adverse kidney events in critically ill patients may help target therapy, allow risk adjustment, and facilitate the conduct of clinical trials. In a cohort comprised of all critically ill adults admitted to five intensive care units at a single tertiary care center over one year, we developed a logistic regression model for the outcome of Major Adverse Kidney Events within 30 days (MAKE30), the composite of persistent renal dysfunction, new renal replacement therapy (RRT), and in-hospital mortality. Proposed risk factors for the MAKE30 outcome were selected a priori and included age, race, gender, University Health System Consortium (UHC) expected mortality, baseline creatinine, volume of isotonic crystalloid fluid received in the prior 24 h, admission service, intensive care unit (ICU), source of admission, mechanical ventilation or receipt of vasopressors within 24 h of ICU admission, renal replacement therapy prior to ICU admission, acute kidney injury, chronic kidney disease as defined by baseline creatinine value, and renal failure as defined by the Elixhauser index. Among 10,983 patients in the study population, 1489 patients (13.6%) met the MAKE30 endpoint. The strongest independent predictors of MAKE30 were UHC expected mortality (OR 2.32 [95%CI 2.06-2.61]) and presence of acute kidney injury at ICU admission (OR 4.98 [95%CI 4.12-6.03]). The model had strong predictive properties including excellent discrimination with a bootstrap-corrected area-under-the-curve (AUC) of 0.903, and high precision of calibration with a mean absolute error prediction of 1.7%. The MAKE30 composite outcome can be reliably predicted from factors present within 24 h of ICU admission using data derived from the electronic health record.

  6. New stratigraphic and isotopic record of the Toarcian Oceanic Anoxic Event from Hungary

    NASA Astrophysics Data System (ADS)

    Müller, Tamás; Price, Gregory; Bajnai, Dávid; Nyerges, Anita; Pálfy, József; May, Zoltán

    2016-04-01

    In the Early Toarcian (˜183 Ma) major global environmental changes took place in the ocean-atmosphere system, including the widely discussed Toarcian Oceanic Anoxic Event (T-OAE). This phenomenon is characterized by strong perturbation of the carbon-cycle and other geochemical systems. A peculiar negative carbon-isotope excursion (CIE) is a hallmark of the event, reflecting the injection of large amount of isotopically light carbon into the ocean-atmosphere system, possible due to dissociation of gas-hydrate from shelf areas. This observed negative CIE and a subsequent broad positive anomaly could be also key signals for chemostratigraphical correlation. In our study we obtained new, high-resolution organic carbon isotope data from the Réka Valley section of the Mecsek Mts. in southern Hungary. The Mecsek Basin was located at the European margin where a thick Lower Jurassic succession of siliciclastic hemipelagic sediments is interrupted by 13 m of organic-rich black shales in the Lower Toarcian. The δ13Corg data from the Réka Valley section is characterized by very negative values (averaging -32), with apparently cyclic fluctuation. The shape of the δ13Corg shows that a continuous and complete record can be found in the Réka Valley and also suggests mixed features between the carbon isotope record of the NW European and Tethyan regions. We have also carried out high resolution handheld XRF analyzes to study cyclostratigraphic signals in the section. The distribution of four elements Ti, Ca, Si and Al were used in our studies beside the δ13Corg data. The duration for the negative shift at Réka Valley, calculated from XRF signals, is either 550-750 kyr, 200-275 kyr or 116-158 kyr, based on 100 kyr short eccentricity, 36.6 kyr obliquity or 21.1 kyr precession signals, respectively. Several previous studies concluded that the most probable astronomical forcing factor during the CIE of the Toarcian OAE is obliquity. Therefore, we assume a duration around 200

  7. Genomic selection for producer-recorded health event data in US dairy cattle.

    PubMed

    Parker Gaddis, K L; Cole, J B; Clay, J S; Maltecca, C

    2014-05-01

    Emphasizing increased profit through increased dairy cow production has revealed a negative relationship of production with fitness and health traits. Decreased cow health can affect herd profitability through increased rates of involuntary culling and decreased or lost milk sales. The development of genomic selection methodologies, with accompanying substantial gains in reliability for low-heritability traits, may dramatically improve the feasibility of genetic improvement of dairy cow health. Producer-recorded health information may provide a wealth of information for improvement of dairy cow health, thus improving profitability. The principal objective of this study was to use health data collected from on-farm computer systems in the United States to estimate variance components and heritability for health traits commonly experienced by dairy cows. A single-step analysis was conducted to estimate genomic variance components and heritabilities for health events, including cystic ovaries, displaced abomasum, ketosis, lameness, mastitis, metritis, and retained placenta. A blended H matrix was constructed for a threshold model with fixed effects of parity and year-season and random effects of herd-year and sire. The single-step genomic analysis produced heritability estimates that ranged from 0.02 (standard deviation = 0.005) for lameness to 0.36 (standard deviation = 0.08) for retained placenta. Significant genetic correlations were found between lameness and cystic ovaries, displaced abomasum and ketosis, displaced abomasum and metritis, and retained placenta and metritis. Sire reliabilities increased, on average, approximately 30% with the incorporation of genomic data. From the results of these analyses, it was concluded that genetic selection for health traits using producer-recorded data are feasible in the United States, and that the inclusion of genomic data substantially improves reliabilities for these traits. Copyright © 2014 American Dairy Science

  8. Sudden cardiac arrest recorded during Holter monitoring: prevalence, antecedent electrical events, and outcomes.

    PubMed

    Watanabe, Eiichi; Tanabe, Teruhisa; Osaka, Motohisa; Chishaki, Akiko; Takase, Bonpei; Niwano, Shinichi; Watanabe, Ichiro; Sugi, Kaoru; Katoh, Takao; Takayanagi, Kan; Mawatari, Koushi; Horie, Minoru; Okumura, Ken; Inoue, Hiroshi; Atarashi, Hirotsugu; Yamaguchi, Iwao; Nagasawa, Susumu; Moroe, Kazuo; Kodama, Itsuo; Sugimoto, Tsuneaki; Aizawa, Yoshifusa

    2014-08-01

    Causative arrhythmias of sudden cardiac arrest (SCA) are changing in this age of improved coronary care. The purpose of this study was to examine the frequency of terminal arrhythmias and the electrical events prior to SCA. We analyzed 24-hour Holter recordings of 132 patients enrolled from 41 institutions who either died (n = 88) or had an aborted death (n = 44). The Holter recordings were obtained for diagnosing and evaluating diseases and arrhythmias in those without any episodes suggestive of SCA. In 97 patients (73%), SCA was associated with ventricular tachyarrhythmias and in 35 (27%) with bradyarrhythmias. The bradyarrhythmia-related SCA patients were older than those with a tachyarrhythmia-related SCA (70 ± 13 years vs. 58 ± 19 years, P < .001). The most common arrhythmia for a tachyarrhythmia-related SCA was ventricular tachycardia degenerating to ventricular fibrillation (45%). The bradyarrhythmia-related SCA was caused by asystole (74%) or AV block (26%). Spontaneous conversion was observed in 37 patients (38%) with ventricular tachyarrhythmias. Of those, 62% of the patients experienced symptoms including syncope, chest pain, or convulsion. Multivariate logistic analysis revealed that independent predictors of mortality for tachyarrhythmia-related SCAs were advanced age (odds ratio 1.04, 95% confidence interval 1.02-1.08) and ST elevation within the hour before SCA (odds ratio 3.54, 95% confidence interval 1.07-13.5). In contrast, the presence of preceding torsades de pointes was associated with spontaneous conversion (odds ratio 0.20, 95% confidence interval 0.05-0.66). The most frequent cause of SCA remains ventricular tachyarrhythmias. Advanced age and ST elevation before SCA are risk factors for mortality in tachyarrhythmia-related SCAs. Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  9. Cine and television recording and image-processing systems for studies of fast-progressing processes

    NASA Astrophysics Data System (ADS)

    Konovalov, Nikolai A.; Veselovsky, Vladimir B.; Kovalenko, Vladimir I.; Lakhno, Nikolay I.; Skorik, Alexander D.; Furmanov, Valeri B.; Polyakov, Gennadiy A.

    1996-06-01

    The methods and software of the fast-running processes' investigation in various media (solids, liquids, gas, plasma) and technical objects were developed. The mathematical models of the objects under research were created in the conditions of exposure to the fields possessing different physical nature. The hardware and programming complex of the film-phototelerecording and data processing combining the computer equipment, television- and film technique, was created, permitting the use of the advantages of every type of the technical systems for the investigation of certain processes, objects and their characteristics. The hardware and programming complex of the film-phototelerecording and data processing is used both in the development and designing periods, and during tests, as well as under the long-term operation of technical objects in the ordinary and extremal situations. The fast-running processes' investigations in various media and technical objects were performed, and by their results the data bank was made.

  10. Neogene paleoceanographic events recorded in an active-margin setting: Humboldt basin, California

    USGS Publications Warehouse

    McCrory, P.A.

    1990-01-01

    Recognition of North Pacific paleoceanographic events in the marginal Humboldt (Eel River) basin of northern California enables correlation of stratigraphic sections and development of a chronostratigraphy. Paleoclimatically related coiling shifts in Neogloboquadrina pachyderma (Ehrenberg) and benthic foraminiferal datums form the basis of the chronostratigraphy. Benthic foraminiferal datums are defined by the occurrence of selected benthic species and abundance maxima of benthic biofacies. The compiled chronostratigraphy is used to refine reconstructions of the depositional history of Humboldt basin. Paleoceanographic events, recognized by the distribution of benthic foraminiferal biofacies, are used to infer paleoceanographic history along the northeastern Pacific margin. The similarity in coiling curves of N. pachyderma from the marine sequence at DSDP Site 173 and the coastal Centerville Beach section of Humboldt basin and at other independently dated sites along the northeastern Pacific margin demonstrates that matching records of climatic oscillations is a reliable method of correlating marine sequences. Benthic fauna from the Centerville Beach section vary in phase with climatically related coiling shifts in N. pachyderma. In particular these data show an increase in displaced neritic fauna during inferred warm intervals and resurgence of deeper bathyal fauna during inferred cool events. Similar data are observed from the inland Eel River section, demonstrating that benthic foraminiferal trends recognized at Centerville Beach can be identified elsewhere in Humboldt basin. This in-phase benthic response to climatic fluctuations probably results from changes in vertical depth range of many benthic species in response to paleoclimatically related vertical changes in water-mass position. Depositional histories reconstructed for two key sites in southern Humboldt basin indicate low rates of sediment accumulation during early basin filling with hemipelagic

  11. Diamond Morphology: Link to Metasomatic Events in the Mantle or Record of Evolution of Kimberlitic Fluid?

    NASA Astrophysics Data System (ADS)

    Fedortchouk, Y.

    2009-05-01

    Morphology and surface features on diamonds show tremendous variation even within a single kimberlite body reflecting a complex history of growth and dissolution. But does the diamond surface record the conditions in the several mantle sources sampled by the rising kimberlite magma, or evolution of the fluid system in the kimberlite magma itself? To address this question I revised morphological classification of diamonds from several kimberlite pipes from EKATI Mine property, N.W.T., Canada. The novelty of the approach, compared to the existing classifications, is in utilizing a random but large dataset of diamond dissolution experiments accumulated by several researchers including myself. These experiments have shown that similar forms (e.g. trigon etch pits) can be produced in a variety of conditions and environments, whereas their shape and size would depend on the reactant. Similarly, different types of resorption features always form together and can be used for deriving the composition of oxidizing fluid. The proposed classification method is focused on relating various types of diamond surfaces to the composition and conditions of oxidizing media. The study uses parcels of micro-and macro-diamonds (total of 125 carats) from Misery, Grizzly, Leslie and Koala kimberlites, EKATI Mine property, Northwest Territories, Canada. Only octahedron and hexoctahedron diamonds were selected (total ~600 stones). Diamond surfaces were studied using an optical and Field- Emission Scanning Electron Microscope to define resorption elements - simple surface features. These elements were identified for each of the three categories: 1) present on octahedral faces (well-preserved diamonds), 2) present on hexoctahedral faces (rounded resorbed diamonds), and 3) frosting (micro-features). Consistent associations of several elements define Resorption Types of diamonds, which form during a single oxidizing event. We further relate these types to the composition of the C-H-O + chlorides

  12. Evaluation of the southern California seismic velocity models through simulation of recorded events

    NASA Astrophysics Data System (ADS)

    Taborda, Ricardo; Azizzadeh-Roodpish, Shima; Khoshnevis, Naeem; Cheng, Keli

    2016-06-01

    Significant effort has been devoted over the last two decades to the development of various seismic velocity models for the region of southern California, United States. These models are mostly used in forward wave propagation simulation studies, but also as base models for tomographic and source inversions. Two of these models, the community velocity models CVM-S and CVM-H, are among the most commonly used for this region. This includes two alternative variations to the original models, the recently released CVM-S4.26 which incorporates results from a sequence of tomographic inversions into CVM-S, and the user-controlled option of CVM-H to replace the near-surface profiles with a VS30-based geotechnical model. Although either one of these models is regarded as acceptable by the modeling community, it is known that they have differences in their representation of the crustal structure and sedimentary deposits in the region, and thus can lead to different results in forward and inverse problems. In this paper, we evaluate the accuracy of these models when used to predict the ground motion in the greater Los Angeles region by means of an assessment of a collection of simulations of recent events. In total, we consider 30 moderate-magnitude earthquakes (3.5 < Mw < 5.5) between 1998 and 2014, and compare synthetics with data recorded by seismic networks during these events. The simulations are done using a finite-element parallel code, with numerical models that satisfy a maximum frequency of 1 Hz and a minimum shear wave velocity of 200 m s-1. The comparisons between data and synthetics are ranked quantitatively by means of a goodness-of-fit (GOF) criteria. We analyse the regional distribution of the GOF results for all events and all models, and draw conclusions from the results and how these correlate to the models. We find that, in light of our comparisons, the model CVM-S4.26 consistently yields better results.

  13. The large Type 4 radio burst event of 24 April 1985 interpreted by dynamic spectral recordings and associated recordings

    NASA Technical Reports Server (NTRS)

    Urbarz, H. W.

    1987-01-01

    The Active Region 4647 showed a sudden increase in spot area on 23 April 1985 as well as an appearance of the D magneic configuration. During STIP interval XVII numerous subflares occurred in this region but only one very large event which exhibited all signatures of a classical p-event, well separated in time from other large events. The dynamic spectrum was observed at Bleien, Ondrejov, and Weissenau. The onset of radiation at m- and dm-waves is impulsive, and at dm-waves the preceeding dm continuum rises gradually. The absolute fluxes show very high readings of some 10 to the 4th power SFU at m-waves and some 5 x 10 to the 3d power at cm waves. High energy particles were observed about a day later by IMP 8. A Forbush decrease was seen on the neutron monitors but there was no GLE. The GOES X-ray flux monitors showed a gradual rise to high fluxes and a slow decrease over several hours. This information was extracted from Gdata but also from numerous letters from other observers and interpreters. More detailed data on the event and on the concomitant active region are to be presented.

  14. Fasting triglycerides predict recurrent ischemic events in patients with acute coronary syndrome treated with statins.

    PubMed

    Schwartz, Gregory G; Abt, Markus; Bao, Weihang; DeMicco, David; Kallend, David; Miller, Michael; Mundl, Hardi; Olsson, Anders G

    2015-06-02

    Most patients with acute coronary syndrome (ACS) are treated with statins, which reduce atherogenic triglyceride-rich lipoproteins. It is uncertain whether triglycerides predict risk after ACS on a background of statin treatment. This study examined the relationship of fasting triglyceride levels to outcomes after ACS in patients treated with statins. Long-term and short-term relationships of triglycerides to risk after ACS were examined in the dal-OUTCOMES trial and atorvastatin arm of the MIRACL (Myocardial Ischemia Reduction with Acute Cholesterol Lowering) trial, respectively. Analysis of dal-OUTCOMES included 15,817 patients (97% statin-treated) randomly assigned 4 to 12 weeks after ACS to treatment with dalcetrapib (a cholesteryl ester transfer protein inhibitor) or placebo and followed for a median 31 months. Analysis of MIRACL included 1,501 patients treated with atorvastatin 80 mg daily beginning 1 to 4 days after ACS and followed for 16 weeks. Fasting triglycerides at initial random assignment were related to risk of coronary heart disease death, nonfatal myocardial infarction, stroke, and unstable angina in models adjusted for age, sex, hypertension, smoking, diabetes, high-density lipoprotein cholesterol, and body mass index. Fasting triglyceride levels were associated with both long-term and short-term risk after ACS. In dal-OUTCOMES, long-term risk increased across quintiles of baseline triglycerides (p<0.001). The hazard ratio in the highest/lowest quintile (>175/≤80 mg/dl) was 1.61 (95% confidence interval: 1.34 to 1.94). There was no interaction of triglycerides and treatment assignment on the primary outcome. In the atorvastatin group of MIRACL, short-term risk increased across tertiles of baseline triglycerides (p=0.03), with a hazard ratio of 1.50 [corrected] (95% confidence interval: 1.05 to 2.15) in highest/lowest tertiles (>195/≤135 mg/dl). The relationship of triglycerides to risk was independent of low-density lipoprotein cholesterol in

  15. Neurophysiological Effects of Meditation Based on Evoked and Event Related Potential Recordings

    PubMed Central

    Singh, Nilkamal; Telles, Shirley

    2015-01-01

    Evoked potentials (EPs) are a relatively noninvasive method to assess the integrity of sensory pathways. As the neural generators for most of the components are relatively well worked out, EPs have been used to understand the changes occurring during meditation. Event-related potentials (ERPs) yield useful information about the response to tasks, usually assessing attention. A brief review of the literature yielded eleven studies on EPs and seventeen on ERPs from 1978 to 2014. The EP studies covered short, mid, and long latency EPs, using both auditory and visual modalities. ERP studies reported the effects of meditation on tasks such as the auditory oddball paradigm, the attentional blink task, mismatched negativity, and affective picture viewing among others. Both EP and ERPs were recorded in several meditations detailed in the review. Maximum changes occurred in mid latency (auditory) EPs suggesting that maximum changes occur in the corresponding neural generators in the thalamus, thalamic radiations, and primary auditory cortical areas. ERP studies showed meditation can increase attention and enhance efficiency of brain resource allocation with greater emotional control. PMID:26137479

  16. Decoupling biogeochemical records, extinction, and environmental change during the Cambrian SPICE event

    PubMed Central

    Schiffbauer, James D.; Huntley, John Warren; Fike, David A.; Jeffrey, Matthew Jarrell; Gregg, Jay M.; Shelton, Kevin L.

    2017-01-01

    Several positive carbon isotope excursions in Lower Paleozoic rocks, including the prominent Upper Cambrian Steptoean Positive Carbon Isotope Excursion (SPICE), are thought to reflect intermittent perturbations in the hydrosphere-biosphere system. Models explaining these secular changes are abundant, but the synchronicity and regional variation of the isotope signals are not well understood. Examination of cores across a paleodepth gradient in the Upper Cambrian central Missouri intrashelf basin (United States) reveals a time-transgressive, facies-dependent nature of the SPICE. Although the SPICE event may be a global signal, the manner in which it is recorded in rocks should and does vary as a function of facies and carbonate platform geometry. We call for a paradigm shift to better constrain facies, stratigraphic, and biostratigraphic architecture and to apply these observations to the variability in magnitude, stratigraphic extent, and timing of the SPICE signal, as well as other biogeochemical perturbations, to elucidate the complex processes driving the ocean-carbonate system. PMID:28275734

  17. Medical Record Validation of Maternal Recall of Pregnancy and Birth Events From a Twin Cohort

    PubMed Central

    Liu, Jianghong; Tuvblad, Catherine; Li, Linda; Raine, Adrian; Baker, Laura A.

    2014-01-01

    This study aims to assess the validity of maternal recall for several perinatal variables 8–10 years after pregnancy in a twin sample. Retrospective information was collected 8–10 years after the delivery event in a cohort of mothers from the University of Southern California Twin Study (N = 611) and compared with medical records for validity analysis. Recall of most variables showed substantial to perfect agreement (κ = 0.60–1.00), with notable exceptions for specific medical problems during pregnancy (κ ≤ 0.40) and substance use when mothers provided continuous data (e.g., number of cigarettes per day; r ≤ 0.24). With the exception of delivery method, neonatal intensive care unit admission, birth weight, neonatal information, and post-delivery complications were also recalled with low accuracy. For mothers of twins, maternal recall is generally a valid measure for perinatal variables 10 years after pregnancy. However, caution should be taken regarding variables such as substance use, medical problems, birth length, and post-delivery complications. PMID:23725849

  18. Long-term memory: a natural mechanism for the clustering of extreme events and anomalous residual times in climate records.

    PubMed

    Bunde, Armin; Eichner, Jan F; Kantelhardt, Jan W; Havlin, Shlomo

    2005-02-04

    We study the statistics of the return intervals between extreme events above a certain threshold in long-term persistent records. We find that the long-term memory leads (i) to a stretched exponential distribution of the return intervals, (ii) to a pronounced clustering of extreme events, and (iii) to an anomalous behavior of the mean residual time to the next event that depends on the history and increases with the elapsed time in a counterintuitive way. We present an analytical scaling approach and demonstrate that all these features can be seen in long climate records. The phenomena should also occur in heartbeat records, Internet traffic, and stock market volatility and have to be taken into account for an efficient risk evaluation.

  19. A geostatistical extreme-value framework for fast simulation of natural hazard events.

    PubMed

    Youngman, Benjamin D; Stephenson, David B

    2016-05-01

    We develop a statistical framework for simulating natural hazard events that combines extreme value theory and geostatistics. Robust generalized additive model forms represent generalized Pareto marginal distribution parameters while a Student's t-process captures spatial dependence and gives a continuous-space framework for natural hazard event simulations. Efficiency of the simulation method allows many years of data (typically over 10 000) to be obtained at relatively little computational cost. This makes the model viable for forming the hazard module of a catastrophe model. We illustrate the framework by simulating maximum wind gusts for European windstorms, which are found to have realistic marginal and spatial properties, and validate well against wind gust measurements.

  20. Seismic source associated with the repetitive events recorded at the Nevado del Huila volcano - Colombia in November 2008

    NASA Astrophysics Data System (ADS)

    Trujillo, N.; Valdes-González, C. M.; White, R.; Dawson, P. B.; McCausland, W. A.; Santacoloma, C.

    2016-12-01

    The Nevado del Huila Volcano recorded an eruption on November 21st, 2008. This eruptive event was preceded by approximately 11,200 seismic events associated to fluids dynamic inside volcanic conduits. These seismic signals were classified as Hybrid events (HB), Long Period events (LP) and Drumbeat events, and they presented as fundamental characteristic, great regularity in the time, i. e. their waveforms and their bandwidths were very similar to each other. Cardona et al. (2009) made a first analysis of these signals and proposed the existence of two seismic families: the first integrated by LP events and HB events registered in the period, November 9th to November 21st; and second family composed by the Drumbeats events registered between November 20th and 21st. Our project took as starting point the work of Cardona et al. (2009); we establish the degree of similarity between events of each of the two families proposed by Cardona et al. (2009). First, we made a temporal analysis by using the Hilbert Transform, and then applied the cross-correlation technique. Finally a stacking of the signals with correlation coefficients > 0.9, was obtained. The results were: 8000 events with correlation coefficients > 0.9 and the existence of six possible seismic families. A detailed analysis of the seismic signals obtained through the stacking allowed us to conclude the existence of four families, the first one recorded between the 4th to 18th of November, the second one for the drumbeat events recorded on November 11th, the third one for the seismicity recorded between the 14th and 21st of November, and the four one for the drumbeat events registered on November 20th and 21st. We suggest that each of these families was associated with a different seismic source; so, the first and third families were possibly associated to mechanisms like brittle fracturing that can occur in weak areas where cracks or conduits intersect, and where acoustic resonance can occur, and the second

  1. Fast vision through frameless event-based sensing and convolutional processing: application to texture recognition.

    PubMed

    Perez-Carrasco, Jose Antonio; Acha, Begona; Serrano, Carmen; Camunas-Mesa, Luis; Serrano-Gotarredona, Teresa; Linares-Barranco, Bernabe

    2010-04-01

    Address-event representation (AER) is an emergent hardware technology which shows a high potential for providing in the near future a solid technological substrate for emulating brain-like processing structures. When used for vision, AER sensors and processors are not restricted to capturing and processing still image frames, as in commercial frame-based video technology, but sense and process visual information in a pixel-level event-based frameless manner. As a result, vision processing is practically simultaneous to vision sensing, since there is no need to wait for sensing full frames. Also, only meaningful information is sensed, communicated, and processed. Of special interest for brain-like vision processing are some already reported AER convolutional chips, which have revealed a very high computational throughput as well as the possibility of assembling large convolutional neural networks in a modular fashion. It is expected that in a near future we may witness the appearance of large scale convolutional neural networks with hundreds or thousands of individual modules. In the meantime, some research is needed to investigate how to assemble and configure such large scale convolutional networks for specific applications. In this paper, we analyze AER spiking convolutional neural networks for texture recognition hardware applications. Based on the performance figures of already available individual AER convolution chips, we emulate large scale networks using a custom made event-based behavioral simulator. We have developed a new event-based processing architecture that emulates with AER hardware Manjunath's frame-based feature recognition software algorithm, and have analyzed its performance using our behavioral simulator. Recognition rate performance is not degraded. However, regarding speed, we show that recognition can be achieved before an equivalent frame is fully sensed and transmitted.

  2. Antibiotic translocation through membrane channels: temperature-dependent ion current fluctuation for catching the fast events.

    PubMed

    Mahendran, Kozhinjampara R; Chimerel, Catalin; Mach, Tivadar; Winterhalter, Mathias

    2009-10-01

    Temperature-dependent facilitated permeation of antibiotics through membrane channels was investigated. Here we reconstituted single OmpF trimers from the outer membrane of Escherichia coli (E. coli) into a planar lipid bilayer. The penetration of ampicillin through OmpF causes fluctuation in the ion current, and analysis of the fluctuations at different temperatures allows us to determine the mode of permeation. The residence time of the drug inside the channel decays strongly with temperature, reaching the resolution limit of the instrument at 30 degrees C. The number of events increases exponentially with temperature up to 30 degrees C and then gradually decreases as temperature increases. At room temperature, we observe about 25 events per second per monomer of the trimeric channel and an extrapolation to 37 degrees C gives roughly 50 events. The activation energy for ampicillin translocation through OmpF is estimated to be around 13 kT. Temperature-dependent study gives new insights into the faster translocation of small substrates through biological nanopores.

  3. Was there a '4.2 ka event' in Great Britain and Ireland? Evidence from the peatland record

    NASA Astrophysics Data System (ADS)

    Roland, T. P.; Caseldine, C. J.; Charman, D. J.; Turney, C. S. M.; Amesbury, M. J.

    2014-01-01

    Palaeoenvironmental and archaeological data from several regions around the world show evidence of a multi-centennial climatic event occurring approximately 4200 cal yr BP (4.2 ka). Whilst the climatic change and/or impact of the 4.2 ka event is clear in certain regions, such as western Asia, evidence for the event has yet to be fully evaluated in northwest Europe. This study presents high-resolution, multi-proxy palaeoclimate records from sites in Northern Ireland, ideally located for an objective examination of the nature of the event in Great Britain and Ireland within the broader context of mid-Holocene climate change c. 6.5-2.5 ka. The peatlands of northwest Europe possess considerable potential for the examination of climatic change in the North Atlantic region, demonstrated by the range of palaeohydrological proxy data generated during this study (peat humification, plant macrofossil and testate amoebae analyses) supported by a high-resolution chronology (including comprehensive AMS 14C and tephrochronology). The inter-site testate amoebae reconstructions appear coherent and were combined to produce a regional climatic record, in marked contrast to the plant macrofossil and peat humification records that appear climatically complacent. The testate amoebae reconstruction, however, provides no compelling evidence for a 4.2 ka event signal and is consistent with previously reported studies from across northwest Europe, suggesting the origin and impact of this event is spatially complex.

  4. Classification of EEG recordings by using fast independent component analysis and artificial neural network.

    PubMed

    Kocyigit, Yucel; Alkan, Ahmet; Erol, Halil

    2008-02-01

    Since there is no definite decisive factor evaluated by the experts, visual analysis of EEG signals in time domain may be inadequate. Routine clinical diagnosis requests to analysis of EEG signals. Therefore, a number of automation and computer techniques have been used for this aim. In this study we aim at designing a MLPNN classifier based on the Fast ICA that accurately identifies whether the associated subject is normal or epileptic. By analyzing a data set consisting of 100 normal and 100 epileptic EEG time series, we have found that the MLPNN classifier based on the Fast ICA achieved and sensitivity rate of 98%, and specificity rate of 90.5%. The results demonstrate that the testing performance of the neural network diagnostic system is found to be satisfactory and we think that this system can be used in clinical studies. Since the time series analysis of EEG signals is unsatisfactory and requires specialist clinicians to evaluate, this application brings objectivity to the evaluation of EEG signals.

  5. An underestimated record breaking event - why summer 1540 was likely warmer than 2003

    NASA Astrophysics Data System (ADS)

    Wetter, O.; Pfister, C.

    2013-01-01

    The heat of summer 2003 in Western and Central Europe was claimed to be unprecedented since the Middle Ages on the basis of grape harvest data (GHD) and late wood maximum density (MXD) data from trees in the Alps. This paper shows that the authors of these studies overlooked the fact that the heat and drought in Switzerland in 1540 likely exceeded the amplitude of the previous hottest summer of 2003, because the persistent temperature and precipitation anomaly in that year, described in an abundant and coherent body of documentary evidence, severely affected the reliability of GHD and tree-rings as proxy-indicators for temperature estimates. Spring-summer (AMJJ) temperature anomalies of 4.7 °C to 6.8 °C being significantly higher than in 2003 were assessed for 1540 from a new long Swiss GHD series (1444 to 2011). During the climax of the heat wave in early August the grapes desiccated on the vine, which caused many vine-growers to interrupt or postpone the harvest despite full grape maturity until after the next spell of rain. Likewise, the leaves of many trees withered and fell to the ground under extreme drought stress as would usually be expected in late autumn. It remains to be determined by further research whether and how far this result obtained from local analyses can be spatially extrapolated. Based on the temperature estimates for Switzerland it is assumed from a great number of coherent qualitative documentary evidence about the outstanding heat drought in 1540 that AMJJ temperatures were likely more extreme in neighbouring regions of Western and Central Europe than in 2003. Considering the significance of soil moisture deficits for record breaking heat waves, these results still need to be validated with estimated seasonal precipitation. It is concluded that biological proxy data may not properly reveal record breaking heat and drought events. Such assessments thus need to be complemented with the critical study of contemporary evidence from

  6. The Early Toarcian Oceanic Anoxic Event: A Southern Hemisphere record from Chile

    NASA Astrophysics Data System (ADS)

    Fantasia, Alicia; Föllmi, Karl B.; Adatte, Thierry; Spangenberg, Jorge E.; Bernárdez, Enrique; Mattioli, Emanuela

    2016-04-01

    The Early Toarcian was marked by important environmental changes, marine oxygen deficiency and extensive organic-rich sediment deposition (T-OAE; ˜182 Ma, Early Jurassic). The T-OAE coincides with a marked negative carbon isotope excursion (CIE) recorded in marine carbonate, and marine and terrestrial organic carbon. This is commonly attributed to the massive release of isotopically light carbon to the atmospheric and oceanic reservoirs derived from the destabilization of methane hydrates from marine sediments and/or the emissions of thermogenic methane from the eruption of the Karoo-Ferrar LIP (e.g., Hesselbo et al., 2000; Kemp et al., 2005; Svensen et al., 2007; Mazzini et al., 2010). Moreover, in most documented marine sections, this episode is marked by a generalized crisis in carbonate production and marine invertebrate extinctions (e.g. Jenkyns, 1988; Röhl et al., 2005; Suan et al., 2001). Several studies of the T-OAE have been conducted on sediments in central and northwest Europe, but only few data are available from the Southern Hemisphere, leading to large uncertainty concerning the exact expression of this event in this part of the world. The aims of this study are to characterize the sediments deposited during the Andean equivalents of the tenuicostatum and falciferum European Zones and establish in which way the T-OAE affected this region. In the Early Jurassic, the Andean basin was in a back-arc setting with marine corridors connected to Panthalassa. In this study, we have generated new high-resolution sedimentological, geochemical and mineralogical data from the sections of El Peñon and Quebrada Asiento, located in Chile in the northeastern area of the city of Copiapó, Atacama region. The biostratigraphy of these sections has been studied by von Hillebrandt and Schidt-Effing (1981) and complemented here by a biostratigraphy based on calcareous nannofossils. The sections consist of a succession of marl, limestone and siltstone of Pliensbachian and

  7. Records of the paleoclimate during the fast transgression period (13 ka BP-8 ka BP) from the mud area on the inner shelf of the East China Sea

    NASA Astrophysics Data System (ADS)

    Liu, S.

    2015-12-01

    A 35.30m-long core (MZ02) recovered from a water depth of 32.4m from the inner shelf mud deposit of the East China Sea was analyzed for sedimentary characteristics, color reflectance, clay mineral, and element geochemistry components as well as by AMS 14C dating to research the sedimentation rate, sediment provenance and paleocwan mountainous river and clay fralimate evolution during the fast transgression period in the study area. Rare earth element and clay mineral proxies indicated that the mixed provenance sediment accumulated in the foreshore-nearshore region at the beginning of the fast transgression period, with a higher sedimentation rate of 5.58m/ka. While from 9800-9500 a B.P., the sedimentation rate keep lower about 1.73m/ka, and the sediment provenance changed obviously, silt fraction were apt to Taiction prone to be transported from the Yangtze River. Multiple proxy system including sediment redness (a*), chemical index of alteration (CIA), clay mineral proxy (smectite/kaolinite), major and trace element proxy (CaO/MgO, Ba/Sr) also showed a good paleoclimate record during the fast transgression period, which could be divided into three units. All the proxies changed little during Unit I (13-11.3ka B.P.) and revealed the climate kept in a relative stable level. Obvious fluctuation happened in Unit II (11.3-10.1ka B.P.) and the temperature kept decreasing more than 1ka till the Younger Dryas event, showed a well regional response to global climate changes. While continuous warming trend resumed again in Unit III (10.1-8 ka B.P.), which may be the signal for Holocene warm period. In addition, we also found significant 80yr, 89yr and 100yr cycles in our CIA, CaO/MgO and Ba/Sr records that imply a possible solar influence on the regional climate changes during the fast transgression period. Keywords: East China Sea, provenance, transgression, mud deposit, late Pleistocene, paleoclimate

  8. Two Extreme Climate Events of the Last 1000 Years Recorded in Himalayan and Andean Ice Cores: Impacts on Humans

    NASA Astrophysics Data System (ADS)

    Thompson, L. G.; Mosley-Thompson, E. S.; Davis, M. E.; Kenny, D. V.; Lin, P.

    2013-12-01

    In the last few decades numerous studies have linked pandemic influenza, cholera, malaria, and viral pneumonia, as well as droughts, famines and global crises, to the El Niño-Southern Oscillation (ENSO). Two annually resolved ice core records, one from Dasuopu Glacier in the Himalaya and one from the Quelccaya Ice Cap in the tropical Peruvian Andes provide an opportunity to investigate these relationships on opposite sides of the Pacific Basin for the last 1000 years. The Dasuopu record provides an annual history from 1440 to 1997 CE and a decadally resolved record from 1000 to 1440 CE while the Quelccaya ice core provides annual resolution over the last 1000 years. Major ENSO events are often recorded in the oxygen isotope, insoluble dust, and chemical records from these cores. Here we investigate outbreaks of diseases, famines and global crises during two of the largest events recorded in the chemistry of these cores, particularly large peaks in the concentrations of chloride (Cl-) and fluoride (Fl-). One event is centered on 1789 to 1800 CE and the second begins abruptly in 1345 and tapers off after 1360 CE. These Cl- and F- peaks represent major droughts and reflect the abundance of continental atmospheric dust, derived in part from dried lake beds in drought stricken regions upwind of the core sites. For Dasuopu the likely sources are in India while for Quelccaya the sources would be the Andean Altiplano. Both regions are subject to drought conditions during the El Niño phase of the ENSO cycle. These two events persist longer (10 to 15 years) than today's typical ENSO events in the Pacific Ocean Basin. The 1789 to 1800 CE event was associated with a very strong El Niño event and was coincidental with the Boji Bara famine resulting from extended droughts that led to over 600,000 deaths in central India by 1792. Similarly extensive droughts are documented in Central and South America. Likewise, the 1345 to 1360 CE event, although poorly documented

  9. Patient characteristics associated with venous thromboembolic events: a cohort study using pooled electronic health record data.

    PubMed

    Kaelber, David C; Foster, Wendy; Gilder, Jason; Love, Thomas E; Jain, Anil K

    2012-01-01

    To demonstrate the potential of de-identified clinical data from multiple healthcare systems using different electronic health records (EHR) to be efficiently used for very large retrospective cohort studies. Data of 959 030 patients, pooled from multiple different healthcare systems with distinct EHR, were obtained. Data were standardized and normalized using common ontologies, searchable through a HIPAA-compliant, patient de-identified web application (Explore; Explorys Inc). Patients were 26 years or older seen in multiple healthcare systems from 1999 to 2011 with data from EHR. Comparing obese, tall subjects with normal body mass index, short subjects, the venous thromboembolic events (VTE) OR was 1.83 (95% CI 1.76 to 1.91) for women and 1.21 (1.10 to 1.32) for men. Weight had more effect then height on VTE. Compared with Caucasian, Hispanic/Latino subjects had a much lower risk of VTE (female OR 0.47, 0.41 to 0.55; male OR 0.24, 0.20 to 0.28) and African-Americans a substantially higher risk (female OR 1.83, 1.76 to 1.91; male OR 1.58, 1.50 to 1.66). This 13-year retrospective study of almost one million patients was performed over approximately 125 h in 11 weeks, part time by the five authors. As research informatics tools develop and more clinical data become available in EHR, it is important to study and understand unique opportunities for clinical research informatics to transform the scale and resources needed to perform certain types of clinical research. With the right clinical research informatics tools and EHR data, some types of very large cohort studies can be completed with minimal resources.

  10. Patient characteristics associated with venous thromboembolic events: a cohort study using pooled electronic health record data

    PubMed Central

    Foster, Wendy; Gilder, Jason; Love, Thomas E; Jain, Anil K

    2012-01-01

    Objective To demonstrate the potential of de-identified clinical data from multiple healthcare systems using different electronic health records (EHR) to be efficiently used for very large retrospective cohort studies. Materials and methods Data of 959 030 patients, pooled from multiple different healthcare systems with distinct EHR, were obtained. Data were standardized and normalized using common ontologies, searchable through a HIPAA-compliant, patient de-identified web application (Explore; Explorys Inc). Patients were 26 years or older seen in multiple healthcare systems from 1999 to 2011 with data from EHR. Results Comparing obese, tall subjects with normal body mass index, short subjects, the venous thromboembolic events (VTE) OR was 1.83 (95% CI 1.76 to 1.91) for women and 1.21 (1.10 to 1.32) for men. Weight had more effect then height on VTE. Compared with Caucasian, Hispanic/Latino subjects had a much lower risk of VTE (female OR 0.47, 0.41 to 0.55; male OR 0.24, 0.20 to 0.28) and African-Americans a substantially higher risk (female OR 1.83, 1.76 to 1.91; male OR 1.58, 1.50 to 1.66). This 13-year retrospective study of almost one million patients was performed over approximately 125 h in 11 weeks, part time by the five authors. Discussion As research informatics tools develop and more clinical data become available in EHR, it is important to study and understand unique opportunities for clinical research informatics to transform the scale and resources needed to perform certain types of clinical research. Conclusions With the right clinical research informatics tools and EHR data, some types of very large cohort studies can be completed with minimal resources. PMID:22759621

  11. Unified law of evolution of experimental gouge-filled fault for fast and slow slip events at slider frictional experiments

    NASA Astrophysics Data System (ADS)

    Ostapchuk, Alexey; Saltykov, Nikolay

    2017-04-01

    Excessive tectonic stresses accumulated in the area of rock discontinuity are released while a process of slip along preexisting faults. Spectrum of slip modes includes not only creeps and regular earthquakes but also some transitional regimes - slow-slip events, low-frequency and very low-frequency earthquakes. However, there is still no agreement in Geophysics community if such fast and slow events have mutual nature [Peng, Gomberg, 2010] or they present different physical phenomena [Ide et al., 2007]. Models of nucleation and evolution of fault slip events could be evolved by laboratory experiments in which regularities of shear deformation of gouge-filled fault are investigated. In the course of the work we studied deformation regularities of experimental fault by slider frictional experiments for development of unified law of evolution of fault and revelation of its parameters responsible for deformation mode realization. The experiments were conducted as a classic slider-model experiment, in which block under normal and shear stresses moves along interface. The volume between two rough surfaces was filled by thin layer of granular matter. Shear force was applied by a spring which deformed with a constant rate. In such experiments elastic energy was accumulated in the spring, and regularities of its releases were determined by regularities of frictional behaviour of experimental fault. A full spectrum of slip modes was simulated in laboratory experiments. Slight change of gouge characteristics (granule shape, content of clay), viscosity of interstitial fluid and level of normal stress make it possible to obtained gradual transformation of the slip modes from steady sliding and slow slip to regular stick-slip, with various amplitude of 'coseismic' displacement. Using method of asymptotic analogies we have shown that different slip modes can be specified in term of single formalism and preparation of different slip modes have uniform evolution law. It is shown

  12. Ultra-fast three terminal perpendicular spin-orbit torque MRAM (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Boulle, Olivier; Cubukcu, Murat; Hamelin, Claire; Lamard, Nathalie; Buda-Prejbeanu, Liliana; Mikuszeit, Nikolai; Garello, Kevin; Gambardella, Pietro; Langer, Juergen; Ocker, Berthold; Miron, Mihai; Gaudin, Gilles

    2015-09-01

    The discovery that a current flowing in a heavy metal can exert a torque on a neighboring ferromagnet has opened a new way to manipulate the magnetization at the nanoscale. This "spin orbit torque" (SOT) has been demonstrated in ultrathin magnetic multilayers with structural inversion asymmetry (SIA) and high spin orbit coupling, such as Pt/Co/AlOx multilayers. We have shown that this torque can lead to the magnetization switching of a perpendicularly magnetized nanomagnet by an in-plane current injection. The manipulation of magnetization by SOT has led to a novel concept of magnetic RAM memory, the SOT-MRAM, which combines non volatility, high speed, reliability and large endurance. These features make the SOT-MRAM a good candidate to replace SRAM for non-volatile cache memory application. We will present the proof of concept of a perpendicular SOT-MRAM cell composed of a Ta/FeCoB/MgO/FeCoB magnetic tunnel junction and demonstrate ultra-fast (down to 300 ps) deterministic bipolar magnetization switching. Macrospin and micromagnetic simulations including SOT cannot reproduce the experimental results, which suggests that additional physical mechanisms are at stacks. Our results show that SOT-MRAM is fast, reliable and low power, which is promising for non-volatile cache memory application. We will also discuss recent experiments of magnetization reversal in ultrathin multilayers Pt/Co/AlOx by very short (<200 ps) current pulses. We will show that in this material, the Dzyaloshinskii-Moryia interaction plays a key role in the reversal process.

  13. Fast inference of interactions in assemblies of stochastic integrate-and-fire neurons from spike recordings.

    PubMed

    Monasson, Remi; Cocco, Simona

    2011-10-01

    We present two Bayesian procedures to infer the interactions and external currents in an assembly of stochastic integrate-and-fire neurons from the recording of their spiking activity. The first procedure is based on the exact calculation of the most likely time courses of the neuron membrane potentials conditioned by the recorded spikes, and is exact for a vanishing noise variance and for an instantaneous synaptic integration. The second procedure takes into account the presence of fluctuations around the most likely time courses of the potentials, and can deal with moderate noise levels. The running time of both procedures is proportional to the number S of spikes multiplied by the squared number N of neurons. The algorithms are validated on synthetic data generated by networks with known couplings and currents. We also reanalyze previously published recordings of the activity of the salamander retina (including from 32 to 40 neurons, and from 65,000 to 170,000 spikes). We study the dependence of the inferred interactions on the membrane leaking time; the differences and similarities with the classical cross-correlation analysis are discussed.

  14. 26 CFR 301.9000-4 - Procedure in the event of a request or demand for IRS records or information.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 18 2012-04-01 2012-04-01 false Procedure in the event of a request or demand... demand for IRS records or information. (a) Purpose and scope. This section prescribes procedures to be followed by IRS officers, employees and contractors upon receipt of a request or demand in matters in which...

  15. 26 CFR 301.9000-4 - Procedure in the event of a request or demand for IRS records or information.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 18 2011-04-01 2011-04-01 false Procedure in the event of a request or demand... demand for IRS records or information. (a) Purpose and scope. This section prescribes procedures to be followed by IRS officers, employees and contractors upon receipt of a request or demand in matters in which...

  16. 26 CFR 301.9000-4 - Procedure in the event of a request or demand for IRS records or information.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 18 2014-04-01 2014-04-01 false Procedure in the event of a request or demand... demand for IRS records or information. (a) Purpose and scope. This section prescribes procedures to be followed by IRS officers, employees and contractors upon receipt of a request or demand in matters in which...

  17. Possible explanation of the correlations between events recorded by underground detectors during the Supernova 1987A explosion

    SciTech Connect

    Alexeyev, E. N.

    2010-02-15

    A possible explanation of the time correlations between the data from underground detectors (Baksan telescope, LSD, IMB, Kamiokande II) and from the Rome and Maryland gravitational-wave antennas obtained during the Supernova 1987A explosion is proposed. It is shown that the synchronization of the events recorded by various underground facilities could be produced by gravitational radiation from the Supernova.

  18. The isotropic climatic records in the Alleroed-B{o}lling-Younger Dryas and post-Younger Dryas events

    SciTech Connect

    Epstein, S.

    1995-12-01

    This study compares isotope records of late glacial period climates from Greenland and Alaska. The isotopic composition of dated Alaskan wood samples was determined and compared to isotope data from the Greenland ice cap, pelagic foraminifera, and German pine trees. A time correspondence of large isotopic variations was observed, suggesting that the Allerod-Bolling and Younger Dryas events were widespread in the northern hemisphere, and not restricted to the North Atlantic region. In addition, data indicated that the Allerod-Bolling event was initiated by rapid cooling, and the Younger Dryas event by rapid warming in temperate zones. Consequently, isotopic oscillations recorded at Alaska and Greenland during the Glacial-Interglacial transition are not necessarily associated with temperature variations at those locations. 13 refs., 5 figs.

  19. El nino-southern oscillation events recorded in the stratigraphy of the tropical quelccaya ice cap, peru.

    PubMed

    Thompson, L G; Mosley-Thompson, E; Arnao, B M

    1984-10-05

    Snow accumulation measured during 1982-1983 on the Quelccaya ice cap, Peru, was 70 percent of the average from 1975 through 1983. Inspection of 19 years (1964 through 1983) of accumulation measured near the summit of Quelccaya reveals a substantial decrease ( approximately 30 percent) in association with the last five El Niño-Southern Oscillation (ENSO) occurrences in the equatorial Pacific. The ENSO phenomenon is now recognized as a global event arising from large-scale interactions between the ocean and the atmosphere. Understanding this extreme event, with the goal of prediction, requires a record of past occurrences. The Quelccaya ice cap, which contains 1500 years of annually accumulated ice layers, may provide a long and detailed record of the most extreme ENSO events.

  20. Agreement between ambulance paramedic- and physician-recorded neurological signs with Face Arm Speech Test (FAST) in acute stroke patients.

    PubMed

    Nor, A Mohd; McAllister, C; Louw, S J; Dyker, A G; Davis, M; Jenkinson, D; Ford, G A

    2004-06-01

    Patients with suspected stroke first assessed by ambulance paramedics require early recognition to facilitate appropriate triage and early treatment. We determined paramedic's accuracy in detecting acute stroke signs by comparing agreement between neurological signs recorded in the Face Arm Speech Test (FAST), a stroke recognition instrument, by paramedics on the scene and by stroke physicians after admission. Suspected stroke patients admitted by ambulance paramedics directly to an acute stroke unit through a rapid ambulance protocol were examined by a trainee stroke neurologist or admitting stroke physician over a 1-year period. Recorded neurological signs (facial weakness, arm weakness, speech disturbance) in confirmed acute stroke/transient ischemic attack (TIA) cases were compared between paramedics and the stroke neurologist/physician. Ambulance crews referred 278 suspected stroke patients of whom 217 (78%) had confirmed stroke (n=189) or TIA (n=28); 95% were examined by the stroke neurologist (median 18 hours after paramedic assessment). Recorded signs and agreement between paramedics and stroke physicians in confirmed stroke group were: facial weakness, 68% versus 70% (kappa=0.49; 95% CI: 0.36 to 0.62); arm weakness, 96% versus 95% (kappa=0.77; 95% CI: 0.55 to 0.99); and speech disturbance, 79% versus 77% (kappa=0.69; 95% CI: 0.56 to 0.82). Interrater agreement was complete for arm weakness in 98% cases. Recognition of neurological deficits by ambulance paramedics using FAST shows good agreement with physician assessment, even allowing for temporal evolution of deficits. The high prevalence and good agreement for arm weakness suggest that this sign may have the greatest usefulness for prehospital ambulance triage and paramedic-based neuroprotective trials.

  1. A comparative assessment of immunization records in the Defense Medical Surveillance System and the Vaccine Adverse Event Reporting System.

    PubMed

    McNeil, Michael M; Ma, Guihua; Aranas, Aaron; Payne, Daniel C; Rose, Charles E

    2007-04-30

    We compared immunization data in the Defense Medical Surveillance System (DMSS) and immunization data for service members with an anthrax vaccine-associated adverse event reported to the Vaccine Adverse Event Reporting System (VAERS) during January 1998 through December 2004. Our main measure of agreement was sensitivity of the DMSS conditional on an immunization record(s) occurring in VAERS. The sensitivity of DMSS was 73% for all vaccines and 74% for the anthrax vaccine on the VAERS index immunization date. Our study is the first to quantify the agreement between immunization records in VAERS and DMSS. Our data suggest the immunization information in military VAERS reports and the DMSS is similar for anthrax and non-anthrax immunizations.

  2. Networks of recurrent events, a theory of records, and an application to finding causal signatures in seismicity.

    PubMed

    Davidsen, Jörn; Grassberger, Peter; Paczuski, Maya

    2008-06-01

    We propose a method to search for signs of causal structure in spatiotemporal data making minimal a priori assumptions about the underlying dynamics. To this end, we generalize the elementary concept of recurrence for a point process in time to recurrent events in space and time. An event is defined to be a recurrence of any previous event if it is closer to it in space than all the intervening events. As such, each sequence of recurrences for a given event is a record breaking process. This definition provides a strictly data driven technique to search for structure. Defining events to be nodes, and linking each event to its recurrences, generates a network of recurrent events. Significant deviations in statistical properties of that network compared to networks arising from (acausal) random processes allows one to infer attributes of the causal dynamics that generate observable correlations in the patterns. We derive analytically a number of properties for the network of recurrent events composed by a random process in space and time. We extend the theory of records to treat not only the variable where records happen, but also time as continuous. In this way, we construct a fully symmetric theory of records leading to a number of results. Those analytic results are compared in detail to the properties of a network synthesized from time series of epicenter locations for earthquakes in Southern California. Significant disparities from the ensemble of acausal networks that can be plausibly attributed to the causal structure of seismicity are as follows. (1) Invariance of network statistics with the time span of the events considered. (2) The appearance of a fundamental length scale for recurrences, independent of the time span of the catalog, which is consistent with observations of the "rupture length." (3) Hierarchy in the distances and times of subsequent recurrences. As expected, almost all of the statistical properties of a network constructed from a surrogate

  3. The syndrome coding technique and its application to fast event selection in high-energy physics experiments

    SciTech Connect

    Nikityuk, N.M.

    1993-01-01

    The problems in the use of the theory and practice of algebraic coding theory for data compression and processing in multichannel charged-particle detectors are discussed. A system of analogies between the theories of correcting codes and hodoscopic systems is described. The main result of this approach is the development of radically new logic units, such as parallel encoders for t > 1 signals, majority coincidence circuits for a large number of inputs, dynamically programmable modules, and special-purpose processors with algebraic structure based on elements of the Galois field GF(2{sup m}) for fast event selection. It is also shown how calculations in Galois fields can be used to design dynamically programcontrolled logic modules, which appear promising for use in trigger systems.

  4. Automated scoring of obstructive sleep apnea and hypopnea events using short-term electrocardiogram recordings.

    PubMed

    Khandoker, Ahsan H; Gubbi, Jayavardhana; Palaniswami, Marimuthu

    2009-11-01

    Obstructive sleep apnea or hypopnea causes a pause or reduction in airflow with continuous breathing effort. The aim of this study is to identify individual apnea and hypopnea events from normal breathing events using wavelet-based features of 5-s ECG signals (sampling rate = 250 Hz) and estimate the surrogate apnea index (AI)/hypopnea index (HI) (AHI). Total 82,535 ECG epochs (each of 5-s duration) from normal breathing during sleep, 1638 ECG epochs from 689 hypopnea events, and 3151 ECG epochs from 1862 apnea events were collected from 17 patients in the training set. Two-staged feedforward neural network model was trained using features from ECG signals with leave-one-patient-out cross-validation technique. At the first stage of classification, events (apnea and hypopnea) were classified from normal breathing events, and at the second stage, hypopneas were identified from apnea. Independent test was performed on 16 subjects' ECGs containing 483 hypopnea and 1352 apnea events. The cross-validation and independent test accuracies of apnea and hypopnea detection were found to be 94.84% and 76.82%, respectively, for training set, and 94.72% and 79.77%, respectively, for test set. The Bland-Altman plots showed unbiased estimations with standard deviations of +/- 2.19, +/- 2.16, and +/- 3.64 events/h for AI, HI, and AHI, respectively. Results indicate the possibility of recognizing apnea/hypopnea events based on shorter segments of ECG signals.

  5. Near-Source Recordings of Small and Large Earthquakes: Magnitude Predictability only for Medium and Small Events

    NASA Astrophysics Data System (ADS)

    Meier, M. A.; Heaton, T. H.; Clinton, J. F.

    2015-12-01

    The feasibility of Earthquake Early Warning (EEW) applications has revived the discussion on whether earthquake rupture development follows deterministic principles or not. If it does, it may be possible to predict final earthquake magnitudes while the rupture is still developing. EEW magnitude estimation schemes, most of which are based on 3-4 seconds of near-source p-wave data, have been shown to work well for small to moderate size earthquakes. In this magnitude range, the used time window is larger than the source durations of the events. Whether the magnitude estimation schemes also work for events in which the source duration exceeds the estimation time window, however, remains debated. In our study we have compiled an extensive high-quality data set of near-source seismic recordings. We search for waveform features that could be diagnostic of final event magnitudes in a predictive sense. We find that the onsets of large (M7+) events are statistically indistinguishable from those of medium sized events (M5.5-M7). Significant differences arise only once the medium size events terminate. This observation suggests that EEW relevant magnitude estimates are largely observational, rather than predictive, and that whether a medium size event becomes a large one is not determined at the rupture onset. As a consequence, early magnitude estimates for large events are minimum estimates, a fact that has to be taken into account in EEW alert messaging and response design.

  6. Messinian Salinity Crisis - DREAM (Deep-sea Record of Mediterranean Messinian events) drilling projects

    NASA Astrophysics Data System (ADS)

    Lofi, Johanna; Camerlenghi, Angelo

    2014-05-01

    About 6 My ago the Mediterranean Sea was transformed into a giant saline basin. This event, commonly referred to as the Messinian salinity crisis (MSC), changed the chemistry of the global ocean and had a permanent impact on both the terrestrial and marine ecosystems of a huge area surrounding the Mediterranean area. The first fascinating MSC scenario was proposed following DSDP Leg XIII in 1970 and envisaged an almost desiccated deep Mediterranean basin with a dramatic ~1,500 m drop of sea level, the incision of deep canyons by rivers on the continental margins, and a final catastrophic flooding event when the connections between the Mediterranean Sea and the Atlantic were re-established ~5.33 My ago. In spite of 40 years of multi-disciplinary research conducted on the MSC, modalities, timing, causes, chronology and consequence at local and planetary scale are still not yet fully understood, and the MSC event remains one of the longest-living controversies in Earth Science. Key factor for the controversy is the lack of a complete record of the MSC preserved in the deepest Mediterranean basins. Anywhere else, the MSC mostly generated a sedimentary/time lag corresponding to a widespread erosion surface. Correlations with the offshore depositional units are thus complex, preventing the construction of a coherent scenario linking the outcropping MSC evaporites, the erosion on the margins, and the deposition of clastics and evaporites in the abyssal plains. Recent activity by various research groups in order to identify locations for multiple-site drilling (including riser-drilling) in the Mediterranean Sea that would contribute to solve the open questions still existing about the MSC has culminated in two DREAM Magellan+ Workshops held in 2013 and 2014. A strategy and work plan have been established in order to submit an IODP Multi-phase Drilling Project("Uncovering A Salt Giant")including several site-specific drilling proposals addressing different scientific

  7. Analysis of locality-sensitive hashing for fast critical event prediction on physiological time series.

    PubMed

    Kim, Yongwook Bryce; O'Reilly, Una-May

    2016-08-01

    We apply the sublinear time, scalable locality-sensitive hashing (LSH) and majority discrimination to the problem of predicting critical events based on physiological waveform time series. Compared to using the linear exhaustive k-nearest neighbor search, our proposed method vastly speeds up prediction time up to 25 times while sacrificing only 1% of accuracy when demonstrated on an arterial blood pressure dataset extracted from the MIMIC2 database. We compare two widely used variants of LSH, the bit sampling based (L1LSH) and the random projection based (E2LSH) methods to measure their direct impact on retrieval and prediction accuracy. We experimentally show that the more sophisticated E2LSH performs worse than L1LSH in terms of accuracy, correlation, and the ability to detect false negatives. We attribute this to E2LSH's simultaneous integration of all dimensions when hashing the data, which actually makes it more impotent against common noise sources such as data misalignment. We also demonstrate that the deterioration of accuracy due to approximation at the retrieval step of LSH has a diminishing impact on the prediction accuracy as the speed up gain accelerates.

  8. Concomitant surgical atrial fibrillation ablation and event recorder implantation: better monitoring, better outcome?†

    PubMed Central

    Pecha, Simon; Schäfer, Timm; Hartel, Friederike; Ahmadzade, Teymour; Subbotina, Irina; Reichenspurner, Hermann; Wagner, Florian Matthias

    2013-01-01

    OBJECTIVES Concomitant ablation is an established therapy in cardiac surgical patients with atrial fibrillation (AF). Post-discharge care seems to be an essential factor for clinical outcome. We analysed the influence of event recorder (ER) implantation and therapy guidance by the results of continuous rhythm monitoring of consecutive postoperative follow-up by our department of electrophysiology. METHODS Between July 2003 and August 2010, 401 cardiac surgical patients underwent concomitant surgical AF ablation therapy. Since August 2009, an ER (REVEAL XT, Medtronic, Inc., Minneapolis, MN, USA) was implanted in 98 patients intraoperatively. ER interrogation was performed by our department of electrophysiology 3, 6 and 12 months postoperatively. Results and outcomes were compared with a matched cohort of patients with ablation and no ER implantation. In those patients, rhythm follow-up was obtained by 24-h Holter ECG. Primary end-point of the study was sinus rhythm rate after 12 months. RESULTS Mean patient's age was 67.0 ± 9.7 years, and 68.4% were male. No major ablation-related complications occurred. The overall sinus rhythm rate was 65.3% after 1-year follow-up. The sinus rhythm rate off antiarrhythmic drugs was 60.3%. The conversion rate tended to be higher in patients with an implanted ER (69.3 vs 60.1%, respectively; P = 0.098). Also, the sinus rhythm rate of anti-arrhythmic drugs was higher in the ER group (64.3 vs 56.2). Patients with ER were seen more often by a cardiologist in the first postoperative year (3.1 ± 0.8 vs 1.5 ± 0.9; P < 0.05) and received significantly more additional procedures, like electrical cardioversion or additional catheter-based ablation (16.1 vs 4.3%; P < 0.001; 11.2 vs 3.1%; P < 0.001). CONCLUSIONS Implantation of an ER with link-up to a cardiology and/or electrophysiology provides optimized anti-arrhythmic drug management and higher rates of consecutive procedures like cardioversion or additional catheter-based ablation. As a

  9. [Measurement of patient safety: a systematic review of the reliability and validity of adverse event detection with record review].

    PubMed

    Hanskamp-Sebregts, M; Zegers, M; van Gurp, P J; de Vet, H C W; Wollersheim, H

    2017-01-01

    Record review is the most used method to quantify patient safety. We systematically reviewed the reliability and validity of adverse event detection with record review. A systematic review of the literature. We searched PubMed, EMBASE, CINAHL, PsycINFO and the Cochrane Library and from their inception through February 2015. We included all studies that aimed to describe the reliability and/or validity of record review. Two reviewers conducted data extraction. We pooled κ values (κ) and analysed the differences in subgroups according to number of reviewers, reviewer experience and training level, adjusted for the prevalence of adverse events. In 25 studies, the psychometric data of the Global Trigger Tool (GTT) and the Harvard Medical Practice Study (HMPS) were reported and 24 studies were included for statistical pooling. The inter-raterreliability of the GTT and HMPS showed a pooled κ of 0.65 and 0.55, respectively. The inter-rater agreement was statistically significantly higher when the group of reviewers within a study consisted of a maximum five reviewers. We found no studies reporting on the validity of the GTT and HMPS. The reliability of record review is moderate to substantial and improved when a small group of reviewers carried out record review. The validity of the record review method has never been evaluated, while clinical data registries, autopsy or direct observations of patient care are methods that can be used to test concurrent validity.

  10. Measurement of patient safety: a systematic review of the reliability and validity of adverse event detection with record review

    PubMed Central

    Hanskamp-Sebregts, Mirelle; Zegers, Marieke; Vincent, Charles; van Gurp, Petra J; de Vet, Henrica C W; Wollersheim, Hub

    2016-01-01

    Objectives Record review is the most used method to quantify patient safety. We systematically reviewed the reliability and validity of adverse event detection with record review. Design A systematic review of the literature. Methods We searched PubMed, EMBASE, CINAHL, PsycINFO and the Cochrane Library and from their inception through February 2015. We included all studies that aimed to describe the reliability and/or validity of record review. Two reviewers conducted data extraction. We pooled κ values (κ) and analysed the differences in subgroups according to number of reviewers, reviewer experience and training level, adjusted for the prevalence of adverse events. Results In 25 studies, the psychometric data of the Global Trigger Tool (GTT) and the Harvard Medical Practice Study (HMPS) were reported and 24 studies were included for statistical pooling. The inter-rater reliability of the GTT and HMPS showed a pooled κ of 0.65 and 0.55, respectively. The inter-rater agreement was statistically significantly higher when the group of reviewers within a study consisted of a maximum five reviewers. We found no studies reporting on the validity of the GTT and HMPS. Conclusions The reliability of record review is moderate to substantial and improved when a small group of reviewers carried out record review. The validity of the record review method has never been evaluated, while clinical data registries, autopsy or direct observations of patient care are potential reference methods that can be used to test concurrent validity. PMID:27550650

  11. Thromboembolic and major bleeding events in relation to perioperative bridging of vitamin K antagonists in 649 fast-track total hip and knee arthroplasties

    PubMed Central

    Jørgensen, Christoffer C; Kehlet, Henrik

    2017-01-01

    Background — The benefit of preoperative bridging in surgical patients with continuous anticoagulant therapy is debatable, and drawing of meaningful conclusions may have been limited by mixed procedures with different thromboembolic and bleeding risks in most published studies. Patients and methods — This was an observational cohort treatment study in consecutive primary unilateral total hip and knee arthroplasty patients between January 2010 and November 2013 in 8 Danish fast-track departments. Data were collected prospectively on preoperative comorbidity and anticoagulants in patients with preoperative vitamin K antagonist (VKA) treatment. We performed 30-day follow-up on in-hospital complications and re-admissions through the Danish National Patient Registry and patient records. Results — Of 13,375 procedures, 649 (4.7%) were in VKA patients with a mean age of 73 (SD 9) years and a median length of stay of 3 days (IQR: 2–4). Preoperative bridging was used in 430 (67%), while 215 (33%) were paused. Of 4 arterial thromboembolic events (ATEs) (0.6%), 2 were in paused patients and 2 were in bridged patients (p = 0.6). Of 3 venous thromboembolic events (VTEs) (0.5%), 2 were in paused patients and 1 was in a bridged patient (p = 0.3). Of 8 major bleedings (MBs) (1.2%), 1 was in a paused patient and 7 were in bridged patients (p = 0.3), 5 of whom received therapeutic bridging. Similar results were found in a propensity-matched cohort. Interpretation — In contrast to recent studies in mixed surgical procedures, no statistically significant differences in ATE, VTE, or MB were found between preoperative bridging and pausation of VKA patients. However, the higher number of thromboembolic events in paused patients and the higher number of major bleedings in bridged patients warrant more extensive investigation. PMID:27759465

  12. Early Oligocene geomagnetic field behavior from ODP Site 1128: Complex records of short-period polarity events

    NASA Astrophysics Data System (ADS)

    Molina-Garza, R. S.; Fuller, M. D.

    2001-12-01

    At Site 1128, in the Great Australian Bight, Leg 182 of the Ocean Drilling Program recovered a thick (~350 m) section of Upper Eocene and Lower Oligocene marine calcareous clays. Shipboard measurements established a magnetostratigraphy that can unambiguously be correlated to chrons C13n to C10n of the global polarity time scale (GPTS), and a less complete record of chrons C17n to C15r (due to poor core recovery). Correlation to the GPTS is further supported by available biostratigraphic data. For the Lower Oligocene sequence, average sedimentation rate is estimated at ~4 cm/kyr. The sediments recovered thus allow to test for the completeness and reliability of the geomagnetic field polarity during the Early Oligocene. The original shipboard long-core measurements suggested the presence of additional short polarity events or geomagnetic field excursions during chrons C13n, C12r, C11r, and C11n. In order to examine the reliability of the record and the nature of possible short-polarity events, we obtained discrete samples from the entire sequence at ~1 m intervals, with a closer sample spacing in critical intervals (~10 cm). The natural remanence of these sediments is normally simple. After removing a small soft overprint, the magnetization decays towards the origin with distributed coercivities and distributed unblocking temperatures. Demagnetization behavior and other rock magnetic data indicate that the remanence resides primarily in a cubic phase such as magnetite or maghemite, with a small contribution from hematite. Discrete samples from chron C12r did not reproduce the long-core record for two of the supposed events, single samples suggest the presence of short events or cryptochrons near the base of both C13n and C12r, and multiple samples suggest the existence of short-period normal polarity events during C11r and near the top of C12r. The records of these events are, however, complex. Demagnetization results indicate that the magnetization consists of an

  13. Fast dynamic holographic recording based on conductive ionic metal-alkanoate liquid crystals and smectic glasses.

    PubMed

    Klimusheva, G; Bugaychuk, S; Garbovskiy, Yu; Kolesnyk, O; Mirnaya, T; Ishchenko, A

    2006-01-15

    Recordings of dynamic holograms with microsecond relaxation times under the action of nanosecond laser pulses are obtained in composites on the base of a novel class of liquid crystals (LCs) in ionic metal-alkanoates. Holographic parameters and relaxation characteristics are measured for doped lyotropic ionic LC, for sandwichlike cells (consisting of a dye layer and a layer of the lyotropic ionic LC), and for colored ionic smectic glasses. The structure of the materials is investigated by use of the small-angle x-ray technique. The mechanism of resonance nonlinearity in photosensitive centers and mechanisms of the grating erasure connected with a charge transport in the ionic conductive LC matrix are discussed.

  14. Geomorphological record of extreme wave events during Roman times in the Guadalquivir estuary (Gulf of Cadiz, SW Spain): An archaeological and paleogeographical approach

    NASA Astrophysics Data System (ADS)

    Rodríguez-Ramírez, Antonio; Villarías-Robles, Juan J. R.; Pérez-Asensio, José N.; Santos, Ana; Morales, Juan Antonio; Celestino-Pérez, Sebastián; León, Ángel; Santos-Arévalo, Francisco Javier

    2016-05-01

    Analysis of the geological record has made it possible to delimit for the Guadalquivir estuary the traces of extreme wave events (EWEs) during the Roman period in the Iberian Peninsula (218 BCE to 476 CE). The largest event occurred in the 2nd-3rd century CE. It generated clearly visible erosive effects in the coastal barriers, including washover fans and erosional scarps. In the inner estuary, however, the effects were minor: crevasse splays that broke levees and cheniers, as well as a residual sedimentary lag. The significant development of the spits protected the inner estuary from the marine incursion, which only caused a water level rise with low-regime waves. Correlation of the geomorphological and sedimentary marks left by this event with the archaeological and geological evidence of other events recognized elsewhere in the Gulf of Cadiz effectively argues for a tsunami as to the nature of the 2nd-3rd century CE event. Yet this and the other identified EWEs in the Guadalquivir estuary during the pre-Roman and the Roman period all fit a model of paleogeographic evolution dominated by processes of coastal progradation and estuarine infilling. Radiocarbon dating, geomorphological analysis, and historical references fail to warrant the so-called '218-209 BCE' Atlantic tsunami, as hypothesized in the received scientific literature. In pre-Roman and Roman times, human occupation at the mouth of the Guadalquivir River was strongly influenced by various geodynamic processes, the location of the settlements being contingent upon dependable, fast communication with the sea and, above all, upon adequate protection from EWEs, on the leeward side of spits. Progressive progradation of these coastal barriers combined with the gradual infilling of the estuary to make navigation to open sea increasingly difficult and, eventually, to result in the abandonment of settlements.

  15. Mass Mortality Events in the NW Adriatic Sea: Phase Shift from Slow- to Fast-Growing Organisms

    PubMed Central

    Di Camillo, Cristina Gioia; Cerrano, Carlo

    2015-01-01

    Massive outbreaks are increasing all over the world, which are likely related to climate change. The North Adriatic Sea, a sub-basin of the Mediterranean Sea, is a shallow semi-closed sea receiving high nutrients inputs from important rivers. These inputs sustain the highest productive basin of the Mediterranean Sea. Moreover, this area shows a high number of endemisms probably due to the high diversity of environmental conditions and the conspicuous food availability. Here, we documented two massive mortalities (2009 and 2011) and the pattern of recovery of the affected biocoenoses in the next two years. Results show an impressive and fast shift of the benthic assemblage from a biocoenosis mainly composed of slow-growing and long-lived species to a biocoenosis dominated by fast-growing and short-lived species. The sponge Chondrosia reniformis, one of the key species of this assemblage, which had never been involved in previous massive mortality events in the Mediterranean Sea, reduced its coverage by 70%, and only few small specimens survived. All the damaged sponges, together with many associated organisms, were detached by rough-sea conditions, leaving large bare areas on the rocky wall. Almost three years after the disease, the survived specimens of C. reniformis did not increase significantly in size, while the bare areas were colonized by fast-growing species such as stoloniferans, hydrozoans, mussels, algae, serpulids and bryozoans. Cnidarians were more resilient than massive sponges since they quickly recovered in less than one month. In the study area, the last two outbreaks caused a reduction in the filtration efficiency of the local benthic assemblage by over 60%. The analysis of the times series of wave heights and temperature revealed that the conditions in summer 2011 were not so extreme as to justify severe mass mortality, suggesting the occurrence of other factors which triggered the disease. The long-term observations of a benthic assemblage in the

  16. Mass Mortality Events in the NW Adriatic Sea: Phase Shift from Slow- to Fast-Growing Organisms.

    PubMed

    Di Camillo, Cristina Gioia; Cerrano, Carlo

    2015-01-01

    Massive outbreaks are increasing all over the world, which are likely related to climate change. The North Adriatic Sea, a sub-basin of the Mediterranean Sea, is a shallow semi-closed sea receiving high nutrients inputs from important rivers. These inputs sustain the highest productive basin of the Mediterranean Sea. Moreover, this area shows a high number of endemisms probably due to the high diversity of environmental conditions and the conspicuous food availability. Here, we documented two massive mortalities (2009 and 2011) and the pattern of recovery of the affected biocoenoses in the next two years. Results show an impressive and fast shift of the benthic assemblage from a biocoenosis mainly composed of slow-growing and long-lived species to a biocoenosis dominated by fast-growing and short-lived species. The sponge Chondrosia reniformis, one of the key species of this assemblage, which had never been involved in previous massive mortality events in the Mediterranean Sea, reduced its coverage by 70%, and only few small specimens survived. All the damaged sponges, together with many associated organisms, were detached by rough-sea conditions, leaving large bare areas on the rocky wall. Almost three years after the disease, the survived specimens of C. reniformis did not increase significantly in size, while the bare areas were colonized by fast-growing species such as stoloniferans, hydrozoans, mussels, algae, serpulids and bryozoans. Cnidarians were more resilient than massive sponges since they quickly recovered in less than one month. In the study area, the last two outbreaks caused a reduction in the filtration efficiency of the local benthic assemblage by over 60%. The analysis of the times series of wave heights and temperature revealed that the conditions in summer 2011 were not so extreme as to justify severe mass mortality, suggesting the occurrence of other factors which triggered the disease. The long-term observations of a benthic assemblage in the

  17. Analysis of long-period events recorded at Mount Etna (Italy) in 1992, and their relationship to eruptive activity

    NASA Astrophysics Data System (ADS)

    Falsaperla, S.; Privitera, E.; Chouet, B.; Dawson, P.

    2002-05-01

    Seismic activity recorded at Mount Etna during 1992 was characterized by long-period (LP) events and tremor with fluctuating amplitudes. These signals were associated with the evolution of the eruptive activity that began on December 14, 1991. Following the occurrence of numerous volcano-tectonic earthquakes at the onset of the eruption, LP events dominated the overall seismicity starting in January, 1992. The LP activity occurred primarily in swarms, which were temporally correlated with episodic collapses of the crater floor in the Northeast Crater. Source depths determined for selected LP events suggest a source region located slightly east of Northeast Crater and extending from the surface to a depth of 2000 m. Based on the characteristic signatures of the time series, four families of LP events are identified. Each family shares common spectral peaks independent of azimuth and distance to the source. These spectral features are used to develop a fluid-filled crack model of the source. We hypothesize that the locus of the LP events represents a segment of the magma feeding system connecting a depressurizing magma body with a dike extending in the SSE direction along the western wall of Valle del Bove, toward the site of the Mount Etna eruption. We surmise that magma withdrawal from the source volume beneath Northeast Crater may have caused repeated collapses of the crater floor. Some collapse events may have produced pressure transients in the subjacent dike which acted as seismic wave sources for LP events.

  18. Holocene climatic events recorded in palaeoflood slackwater deposits along the middle Yiluohe River valley, middle Yellow River basin, China

    NASA Astrophysics Data System (ADS)

    Zhao, Xueru; Huang, Chun Chang; Pang, Jiangli; Zha, Xiaochun; Guo, Yongqiang; Hu, Guiming

    2016-06-01

    Palaeohydrological investigations were carried out in the middle reaches of the Yiluohe River, a major tributary in the lower-middle Yellow River basin. Typical palaeoflood slackwater deposits (SWDs) were identified in the Holocene pedostratigraphy on the cliffy river banks. Analytical results, including magnetic susceptibility and grain-size distribution data, indicated that these SWDs were deposited from the suspended sediment load in flood water. These SWDs are different from eolian loess, soils and aeolian sands in the riverbank profile. They recorded several episodes of extraordinary palaeoflood events. In the Longmenxia reaches of the Yihe River valley, these flood events were dated at 3100-3000 a, 1800-1700 a, 770-610 a, and 420-340 a using the optically stimulated luminescence method in combination with the pedostratigraphic correlations. In the Longhutan reaches of the Luohe River valley, the palaeoflood events were dated at 1975-1466 a, i.e., from the Han to Wei dynasties (AD 25-534), during which the capital city on the river banks was flooded many times, as recorded in the literature. These extraordinary flood events are well correlated chronologically with the known Holocene climatic events that occurred in the Northern Hemisphere. Thus, the monsoonal climate was highly variable with both floods and droughts occurring frequently during these episodes. These results are important for understanding the response of river systems in eastern Asia to global changes.

  19. Linear Methods for Efficient and Fast Separation of Two Sources Recorded with a Single Microphone.

    PubMed

    Bhargava, Saurabh; Blättler, Florian; Kollmorgen, Sepp; Liu, Shih-Chii; Hahnloser, Richard H R

    2015-10-01

    This letter addresses the problem of separating two speakers from a single microphone recording. Three linear methods are tested for source separation, all of which operate directly on sound spectrograms: (1) eigenmode analysis of covariance difference to identify spectro-temporal features associated with large variance for one source and small variance for the other source; (2) maximum likelihood demixing in which the mixture is modeled as the sum of two gaussian signals and maximum likelihood is used to identify the most likely sources; and (3) suppression-regression, in which autoregressive models are trained to reproduce one source and suppress the other. These linear approaches are tested on the problem of separating a known male from a known female speaker. The performance of these algorithms is assessed in terms of the residual error of estimated source spectrograms, waveform signal-to-noise ratio, and perceptual evaluation of speech quality scores. This work shows that the algorithms compare favorably to nonlinear approaches such as nonnegative sparse coding in terms of simplicity, performance, and suitability for real-time implementations, and they provide benchmark solutions for monaural source separation tasks.

  20. Heinrich H1 and 8200 yr B.P. climate events recorded in Hall's Cave, Texas

    NASA Astrophysics Data System (ADS)

    Ellwood, Brooks B.; Gose, Wulf A.

    2006-09-01

    Measurements of magnetic susceptibility (MS) have been performed on a continuous set of samples from a well-dated ˜3 m sequence of sediments collected from Hall's Cave, Edwards Plateau, central Texas. Three major climatic events are represented by distinctive MS increases in the sequence: (1) the Heinrich event H1 (from 17,500 to 17,000 yr B.P.); (2) the end of full glacial conditions on the Edwards Plateau at 14,200 yr B.P.; and (3) the 8200 yr B.P. climatic event (from 8250 to 8050 yr B.P.). In addition, a minor event at 4400 yr B.P. is also well defined here and in Canada, indicating that it is a broadly regional event. These data indicate that all four events represent a shift toward milder climatic conditions accompanied by increased rainfall at this location. The general climatic trends interpreted from the MS data are consistent with independent vertebrate assemblages, floral indicators, and isotopic data recovered from the cave.

  1. Do hurricanes leave unique sedimentological records in floodplain settings? Connecticut River, Tropical Storm Irene and past flood events

    NASA Astrophysics Data System (ADS)

    Yellen, B.; Woodruff, J. D.; Kratz, L. N.; Fallon, A.

    2012-12-01

    In late August, 2011, Tropical Storm Irene passed directly over the Connecticut River watershed causing several low order streams to swell beyond prior historical maximum discharges. Although resultant discharge on the mainstem Connecticut River only amounted to a one in seven year-sized event, its sediment load far exceeded the historical discharge to sediment concentration relationship. Gravity cores taken in off-channel ponds following the hydrograph peak clearly showed deposition of storm-mobilized grains. Samples collected from floodplain forest locations also showed significant accumulation. In both depositional settings, grainsize, lithology and percent organics of flood event deposition differed dramatically from background sedimentation. Long cores collected from these same settings suggest that similar deposits from historical storms of record from the past three centuries are preserved in the floodplain sediment record.; Landsat 5 true color image collected on September 2, 2011 - two days after Tropical Storm Irene left the region.

  2. Expanding neurochemical investigations with multi-modal recording: simultaneous fast-scan cyclic voltammetry, iontophoresis, and patch clamp measurements.

    PubMed

    Kirkpatrick, D C; McKinney, C J; Manis, P B; Wightman, R M

    2016-08-02

    Multi-modal recording describes the simultaneous collection of information across distinct domains. Compared to isolated measurements, such studies can more easily determine relationships between varieties of phenomena. This is useful for neurochemical investigations which examine cellular activity in response to changes in the local chemical environment. In this study, we demonstrate a method to perform simultaneous patch clamp measurements with fast-scan cyclic voltammetry (FSCV) using optically isolated instrumentation. A model circuit simulating concurrent measurements was used to predict the electrical interference between instruments. No significant impact was anticipated between methods, and predictions were largely confirmed experimentally. One exception was due to capacitive coupling of the FSCV potential waveform into the patch clamp amplifier. However, capacitive transients measured in whole-cell current clamp recordings were well below the level of biological signals, which allowed the activity of cells to be easily determined. Next, the activity of medium spiny neurons (MSNs) was examined in the presence of an FSCV electrode to determine how the exogenous potential impacted nearby cells. The activities of both resting and active MSNs were unaffected by the FSCV waveform. Additionally, application of an iontophoretic current, used to locally deliver drugs and other neurochemicals, did not affect neighboring cells. Finally, MSN activity was monitored during iontophoretic delivery of glutamate, an excitatory neurotransmitter. Membrane depolarization and cell firing were observed concurrently with chemical changes around the cell resulting from delivery. In all, we show how combined electrophysiological and electrochemical measurements can relate information between domains and increase the power of neurochemical investigations.

  3. Adaptive sparse signal processing for discrimination of satellite-based radiofrequency (RF) recordings of lightning events

    NASA Astrophysics Data System (ADS)

    Moody, Daniela I.; Smith, David A.

    2015-05-01

    For over two decades, Los Alamos National Laboratory programs have included an active research effort utilizing satellite observations of terrestrial lightning to learn more about the Earth's RF background. The FORTE satellite provided a rich satellite lightning database, which has been previously used for some event classification, and remains relevant for advancing lightning research. Lightning impulses are dispersed as they travel through the ionosphere, appearing as nonlinear chirps at the receiver on orbit. The data processing challenge arises from the combined complexity of the lightning source model, the propagation medium nonlinearities, and the sensor artifacts. We continue to develop modern event classification capability on the FORTE database using adaptive signal processing combined with compressive sensing techniques. The focus of our work is improved feature extraction using sparse representations in overcomplete analytical dictionaries. We explore two possible techniques for detecting lightning events, and showcase the algorithms on few representative data examples. We present preliminary results of our work and discuss future development.

  4. Catastrophic event recorded among Holocene eolianites (Sidi Salem Formation, SE Tunisia)

    NASA Astrophysics Data System (ADS)

    Frébourg, Gregory; Hasler, Claude-Alain; Davaud, Eric

    2010-03-01

    A high-energy deposit cuts through the early Holocene eolianites of the Sidi Salem Formation which forms a ridge along the southeastern coast of Tunisia. The sedimentary structures as well as the paleo-altitude and paleo-location of the outcrop state for a subaqueous deposition by an unusually large catastrophic event. Regarding its age and the related uncertainties, it could be either an exceptional storm, or a landslide or impact triggered tsunami. The mega-tsunami of the 8000 BP collapse of the Valle del Bove valley (Etna Volcano) could be this event, for its matching age and calculated run-up height.

  5. Depicting adverse events in cardiac theatre: the preliminary conception of the RECORD model

    PubMed Central

    2013-01-01

    Human error is a byproduct of the human activity and may results in random unintended events; they may have major consequences when it comes to delivery of medicine. Furthermore the causes of error in surgical practice are multifaceted and complex. This article aims to raise awareness for safety measures in the cardiac surgical room and briefly “touch upon” the human factors that could lead to adverse outcomes. Finally, we describe a model that would enable us to depict and study adverse events in the operating theatre. PMID:23510398

  6. Multiple impact events recorded in the NWA 7298 H chondrite breccia and the dynamical evolution of an ordinary chondrite asteroid

    NASA Astrophysics Data System (ADS)

    Friedrich, Jon M.; Weisberg, Michael K.; Rivers, Mark L.

    2014-05-01

    The major geologic process that has shaped the asteroids and led to development of their regoliths is impact. Petrofabrics in ordinary chondrites are undoubtedly the result of impact events on their asteroidal parent bodies and the foliation present in a chondrite serves as an enduring record of the magnitude of the most intense compacting event experienced by the material. An overwhelming majority of chondrites have an internally consistent petrofabric contained within the spatial dimensions of the entire rock, including across clasts or different petrographic domains. This indicates that the magnitude of the most recent impact to have affected the assembled chondrite was significant enough to impart a foliation across all lithologies. Information of any previous impacts is largely lost because of the consistent, realigned foliations. We present X-ray microtomography derived 3D petrofabric intensity and orientation data for three lithologies in the NWA 7298 breccia. The internally inconsistent petrofabrics among differing lithologies indicate that the magnitude of the final impact event was smaller than previous ones. This latter case preserves fabric information recorded during previous impacts and allows a more complete interpretation of the impact history of a local region of the asteroidal parent. We used our data to infer the sequence and intensity of distinct impact events affecting the NWA 7298 parent asteroid. We suggest a near-surface impact debris zone on the H chondrite parent asteroid as an origin for NWA 7298. These observations yield new opportunities for investigating and interpreting the dynamic collisional evolution of asteroids.

  7. Proposal and evaluation of FASDIM, a Fast And Simple De-Identification Method for unstructured free-text clinical records.

    PubMed

    Chazard, Emmanuel; Mouret, Capucine; Ficheur, Grégoire; Schaffar, Aurélien; Beuscart, Jean-Baptiste; Beuscart, Régis

    2014-04-01

    Medical free-text records enable to get rich information about the patients, but often need to be de-identified by removing the Protected Health Information (PHI), each time the identification of the patient is not mandatory. Pattern matching techniques require pre-defined dictionaries, and machine learning techniques require an extensive training set. Methods exist in French, but either bring weak results or are not freely available. The objective is to define and evaluate FASDIM, a Fast And Simple De-Identification Method for French medical free-text records. FASDIM consists in removing all the words that are not present in the authorized word list, and in removing all the numbers except those that match a list of protection patterns. The corresponding lists are incremented in the course of the iterations of the method. For the evaluation, the workload is estimated in the course of records de-identification. The efficiency of the de-identification is assessed by independent medical experts on 508 discharge letters that are randomly selected and de-identified by FASDIM. Finally, the letters are encoded after and before de-identification according to 3 terminologies (ATC, ICD10, CCAM) and the codes are compared. The construction of the list of authorized words is progressive: 12h for the first 7000 letters, 16 additional hours for 20,000 additional letters. The Recall (proportion of removed Protected Health Information, PHI) is 98.1%, the Precision (proportion of PHI within the removed token) is 79.6% and the F-measure (harmonic mean) is 87.9%. In average 30.6 terminology codes are encoded per letter, and 99.02% of those codes are preserved despite the de-identification. FASDIM gets good results in French and is freely available. It is easy to implement and does not require any predefined dictionary. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  8. Daily life event segmentation for lifestyle evaluation based on multi-sensor data recorded by a wearable device.

    PubMed

    Li, Zhen; Wei, Zhiqiang; Jia, Wenyan; Sun, Mingui

    2013-01-01

    In order to evaluate people's lifestyle for health maintenance, this paper presents a segmentation method based on multi-sensor data recorded by a wearable computer called eButton. This device is capable of recording more than ten hours of data continuously each day in multimedia forms. Automatic processing of the recorded data is a significant task. We have developed a two-step summarization method to segment large datasets automatically. At the first step, motion sensor signals are utilized to obtain candidate boundaries between different daily activities in the data. Then, visual features are extracted from images to determine final activity boundaries. It was found that some simple signal measures such as the combination of a standard deviation measure of the gyroscope sensor data at the first step and an image HSV histogram feature at the second step produces satisfactory results in automatic daily life event segmentation. This finding was verified by our experimental results.

  9. Daily Life Event Segmentation for Lifestyle Evaluation Based on Multi-Sensor Data Recorded by a Wearable Device*

    PubMed Central

    Li, Zhen; Wei, Zhiqiang; Jia, Wenyan; Sun, Mingui

    2013-01-01

    In order to evaluate people’s lifestyle for health maintenance, this paper presents a segmentation method based on multi-sensor data recorded by a wearable computer called eButton. This device is capable of recording more than ten hours of data continuously each day in multimedia forms. Automatic processing of the recorded data is a significant task. We have developed a two-step summarization method to segment large datasets automatically. At the first step, motion sensor signals are utilized to obtain candidate boundaries between different daily activities in the data. Then, visual features are extracted from images to determine final activity boundaries. It was found that some simple signal measures such as the combination of a standard deviation measure of the gyroscope sensor data at the first step and an image HSV histogram feature at the second step produces satisfactory results in automatic daily life event segmentation. This finding was verified by our experimental results. PMID:24110323

  10. Completeness and diagnostic validity of recording acute myocardial infarction events in primary care, hospital care, disease registry, and national mortality records: cohort study.

    PubMed

    Herrett, Emily; Shah, Anoop Dinesh; Boggon, Rachael; Denaxas, Spiros; Smeeth, Liam; van Staa, Tjeerd; Timmis, Adam; Hemingway, Harry

    2013-05-20

    admissions was 91.5% (90.8% to 92.1%). Each data source missed a substantial proportion (25-50%) of myocardial infarction events. Failure to use linked electronic health records from primary care, hospital care, disease registry, and death certificates may lead to biased estimates of the incidence and outcome of myocardial infarction. NCT01569139 clinicaltrials.gov.

  11. A re-investigation of the 'double dawn' event recorded in the Bamboo Annals

    NASA Technical Reports Server (NTRS)

    Stephenson, F. R.

    1992-01-01

    An allusion to a 'double dawn' phenomenon in an ancient Chinese chronicle, which has been identified as caused by a sunrise eclipse occurring in 899 BC, is discussed. This event has been regarded as of considerable importance in the investigation of earth's past rotation. It is shown that an eclipse interpretation is implausible, not least because the eclipse in question was only annular.

  12. A re-investigation of the 'double dawn' event recorded in the Bamboo Annals

    NASA Technical Reports Server (NTRS)

    Stephenson, F. R.

    1992-01-01

    An allusion to a 'double dawn' phenomenon in an ancient Chinese chronicle, which has been identified as caused by a sunrise eclipse occurring in 899 BC, is discussed. This event has been regarded as of considerable importance in the investigation of earth's past rotation. It is shown that an eclipse interpretation is implausible, not least because the eclipse in question was only annular.

  13. Measurement of patient safety: a systematic review of the reliability and validity of adverse event detection with record review.

    PubMed

    Hanskamp-Sebregts, Mirelle; Zegers, Marieke; Vincent, Charles; van Gurp, Petra J; de Vet, Henrica C W; Wollersheim, Hub

    2016-08-22

    Record review is the most used method to quantify patient safety. We systematically reviewed the reliability and validity of adverse event detection with record review. A systematic review of the literature. We searched PubMed, EMBASE, CINAHL, PsycINFO and the Cochrane Library and from their inception through February 2015. We included all studies that aimed to describe the reliability and/or validity of record review. Two reviewers conducted data extraction. We pooled κ values (κ) and analysed the differences in subgroups according to number of reviewers, reviewer experience and training level, adjusted for the prevalence of adverse events. In 25 studies, the psychometric data of the Global Trigger Tool (GTT) and the Harvard Medical Practice Study (HMPS) were reported and 24 studies were included for statistical pooling. The inter-rater reliability of the GTT and HMPS showed a pooled κ of 0.65 and 0.55, respectively. The inter-rater agreement was statistically significantly higher when the group of reviewers within a study consisted of a maximum five reviewers. We found no studies reporting on the validity of the GTT and HMPS. The reliability of record review is moderate to substantial and improved when a small group of reviewers carried out record review. The validity of the record review method has never been evaluated, while clinical data registries, autopsy or direct observations of patient care are potential reference methods that can be used to test concurrent validity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  14. Pleistocene ice-rafted debris events recorded at the Agulhas Plateau - indicators of intermittent Indian-Atlantic gateway closure

    NASA Astrophysics Data System (ADS)

    Ziegler, M.; Hall, I. R.; Siret, P. J.; Zahn, R.

    2012-04-01

    Interocean exchange of heat and salt around South Africa - the so called 'Agulhas Leakage' - is thought to be a key link in the maintenance of the Atlantic meridional overturning circulation (AMOC). It takes place at the Agulhas Retroflection, largely by the intermittent shedding of enormous rings that penetrate into the South Atlantic Ocean (Lutjeharms, 1996, Biastoch et al., 2008; Beal et al., 2011). Recent palaeoceanographic studies suggest that variability in the latitudinal position of the subtropical front (STF) in the Southern Ocean, act as a gatekeeper for the Agulhas retroflection and moreover, that a variable northward migration of the STF potentially modulated the severity of glacial periods by altering the amount of Agulhas leakage with consequences for the AMOC (Bard and Rickaby, 2009). Here we present a high-resolution record of ice rafted debris (IRD) from the southern Agulhas Plateau (sediment core MD02-2588, 41°19,90 S and 25°49,70 E, 2907 m water depth) covering the last 350,000 years. We find distinct millennial scale events with high abundances of IRD in the sediments. Scanning-electron microscope analysis of individual grains shows a wide range of morphologies, with a high degree of angularity being a dominant feature, with surface microfeatures (linear fractures, grooves and troughs) that are typical for glacial origin and transport. We interpret these IRD events as indicators for a northward shift of the Southern Ocean frontal system, thereby allowing sufficient cooling and iceberg survivability as far north as the Agulhas Plateau. Our proxy record suggests significant millennial scale variability of the frontal movements throughout the last three glacial cycles. Largest IRD peaks occur during marine isotope stage 8 (~300 ka BP) and hence during a period for which an extreme northward shift in the STF has been identified previously (Bard and Rickaby, 2009). We compare our IRD record with records of millennial scale climate variability in

  15. Decoupling of carbon isotope records between organic matter and carbonate prior to the Toarcian Oceanic Anoxic Event (Early Jurassic)

    NASA Astrophysics Data System (ADS)

    Bodin, Stephane; Kothe, Tim; Krencker, Francois-Nicolas; Suan, Guillaume; Heimhofer, Ulrich; Immenhauser, Adrian

    2014-05-01

    Across the Pliensbachian-Toarcian boundary (P-To, Early Jurassic), ca. 1 Myr before the Toarcian Oceanic Anoxic Event (T-OAE), an initial negative carbon isotope excursion has been documented in western Tethys sedimentary rocks. In carbonate, its amplitude (2-3 permil) is similar to the subsequent excursion recorded at the onset of the T-OAE. Being also associated with a rapid warming event, the significance of this first carbon isotope shift, in terms of paleoenvironmental interpretation and triggering mechanism, remains however elusive. Taking advantage of expanded and rather continuous sections in the High Atlas of Morocco, several high-resolution, paired organic-inorganic carbon isotope records have been obtained across the Upper Pliensbachian - Lower Toarcian interval. At the onset of the T-OAE, an abrupt 1-2 permil negative shift is recorded in both organic and inorganic phases, succeeded by a relatively longer term 1-2 permil negative trend and a final slow return to pre-excursion conditions. In accordance with previous interpretations, this pattern indicates a perturbation of the entire exogenic carbon isotope reservoir at the onset of the T-OAE by the sudden release of isotopically light carbon into the atmosphere. By contrast, there is no negative shift in carbon isotopes for the P-To event recorded in bulk organic matter of Morocco. Given the strong dominance of terrestrial particles in the bulk organic matter fraction, this absence indicates that massive input of 12C-rich carbon into the atmosphere is not likely to have happened during the P-To event. A pronounced (2 permil) and abrupt negative shift in carbon isotope is however recorded in the bulk carbonate phase. We suggest that this decoupling between organic and inorganic phase is due to changes in the nature of the bulk carbonate phase. Indeed, the negative shift occurs at the lithological transition between Pliensbachian-lowermost Toarcian limestone-marl alternations and the Lower Toarcian marl

  16. Implications of variance in biogeochemical proxy records spanning Mesozoic Oceanic Anoxic Events

    NASA Astrophysics Data System (ADS)

    Gomes, M. L.; Mills, J. V.; Hurtgen, M. T.; Sageman, B. B.

    2013-12-01

    The cycling of key elements through the ocean and atmosphere varied widely in the Mesozoic in response to changes in primary productivity and organic carbon burial, volcanism, weathering, and evaporite burial. Many of these processes have been proposed as triggers for the discreet periods of widespread organic carbon production and/or preservation termed Ocean Anoxic Events or OAE's. Thus, it might be expected that similar patterns of elemental cycling would characterize most major OAE intervals and could be used to help elucidate the controls on initiation and/or termination of these events. Yet this is not the case. In this study we compare the variability of a series of geochemical proxies, focusing on sulfur (S) isotopes of marine sulfate and sulfide minerals, through a series of Mesozoic OAE's. The data set includes our own results from OAE1a (ca. 125Ma) and OAE2 (ca. 94Ma), as well as published data from other events. The results indicate that S cycling varied significantly among the events, despite many similarities in the behavior of carbon isotopes and geochemical indicators of oxygen deficiency. Specifically, S isotope compositions of seawater sulfate and pyrite are quite variable during OAE2 suggesting that a short-term increase in sulfate levels upon a low background occurred at the onset due to enhanced volcanism and/or weathering. In contrast, S isotope compositions of seawater sulfate and pyrite decrease dramatically through the OAE1a and are completely decoupled from the carbon cycle. We evaluate these trends using coupled sulfur and carbon box models and show that patterns of S cycling during OAE1a were predominantly controlled by volcanism, whereas S cycling during OAE2 represents a stronger interplay between volcanic processes and linkage with the carbon cycle. An analysis of the differences in S cycling among events provides improved insight into the suite of processes that interacted to drive large-scale changes in environmental conditions

  17. Luminescence chronologies for sediments recording paleoseismic events and slip rate for the central Garlock fault, California, USA

    NASA Astrophysics Data System (ADS)

    Okubo, S. G.; Wolf, E.; Roder, B. J.; Rhodes, E. J.; McGill, S. F.; Dolan, J. F.; Mcauliffe, L. J.; Lawson, M. J.; Barrera, W. A.

    2012-12-01

    Luminescence dating has a significant role to play in providing chronological control for lacustrine and alluvial sediments that record both tectonic and climatic events. However, poor characteristics in some environments mean that the well-established method of OSL (optically stimulated luminescence) dating of quartz is not well-suited for the material available. In order to overcome this significant limitation, a range of methods based on the IRSL (infra-red stimulated luminescence) and ITL (isothermal thermoluminescence) of K-feldspar are currently under development. The site of El Paso Peaks, California has an established C-14 chronology spanning the last 7,000 years for a series of playa sediments comprising silts and fine sands, with occasional incursions of coarser sands and gravels from the alluvial fan that forms one side of the small ephemeral lake basin. Another barrier is formed by a shutter ridge of the left-lateral central Garlock fault, and this succession of sediments records at least six seismic events. Following collection of a suite of 24 luminescence samples distributed throughout the upper part of this succession, this site provides a rare opportunity to test different luminescence dating protocols in a rigorous fashion. At the site of Christmas Canyon West, a few miles further east, numerous small offsets of depositional and erosional alluvial fan features provide the opportunity to determine slip rates for a variety of timescales spanning the past couple of thousand years, besides forming a record of the timing of several discrete depositional episodes representing local high precipitation events. We review the challenges involved in developing a reliable luminescence chronology for sediment deposition in these contexts, and in relating this chronology to significant environmental events.

  18. A toolbox for the fast information analysis of multiple-site LFP, EEG and spike train recordings

    PubMed Central

    Magri, Cesare; Whittingstall, Kevin; Singh, Vanessa; Logothetis, Nikos K; Panzeri, Stefano

    2009-01-01

    Background Information theory is an increasingly popular framework for studying how the brain encodes sensory information. Despite its widespread use for the analysis of spike trains of single neurons and of small neural populations, its application to the analysis of other types of neurophysiological signals (EEGs, LFPs, BOLD) has remained relatively limited so far. This is due to the limited-sampling bias which affects calculation of information, to the complexity of the techniques to eliminate the bias, and to the lack of publicly available fast routines for the information analysis of multi-dimensional responses. Results Here we introduce a new C- and Matlab-based information theoretic toolbox, specifically developed for neuroscience data. This toolbox implements a novel computationally-optimized algorithm for estimating many of the main information theoretic quantities and bias correction techniques used in neuroscience applications. We illustrate and test the toolbox in several ways. First, we verify that these algorithms provide accurate and unbiased estimates of the information carried by analog brain signals (i.e. LFPs, EEGs, or BOLD) even when using limited amounts of experimental data. This test is important since existing algorithms were so far tested primarily on spike trains. Second, we apply the toolbox to the analysis of EEGs recorded from a subject watching natural movies, and we characterize the electrodes locations, frequencies and signal features carrying the most visual information. Third, we explain how the toolbox can be used to break down the information carried by different features of the neural signal into distinct components reflecting different ways in which correlations between parts of the neural signal contribute to coding. We illustrate this breakdown by analyzing LFPs recorded from primary visual cortex during presentation of naturalistic movies. Conclusion The new toolbox presented here implements fast and data-robust computations

  19. Mergers of Charged Black Holes: Gravitational-wave Events, Short Gamma-Ray Bursts, and Fast Radio Bursts

    NASA Astrophysics Data System (ADS)

    Zhang, Bing

    2016-08-01

    The discoveries of GW150914, GW151226, and LVT151012 suggest that double black hole (BH-BH) mergers are common in the universe. If at least one of the two merging black holes (BHs) carries a certain amount of charge, possibly retained by a rotating magnetosphere, the inspiral of a BH-BH system would drive a global magnetic dipole normal to the orbital plane. The rapidly evolving magnetic moment during the merging process would drive a Poynting flux with an increasing wind power. The magnetospheric activities during the final phase of the merger would make a fast radio burst (FRB) if the BH charge can be as large as a factor of \\hat{q}˜ ({10}-9{--}{10}-8) of the critical charge Q c of the BH. At large radii, dissipation of the Poynting flux energy in the outflow would power a short-duration high-energy transient, which would appear as a detectable short-duration gamma-ray burst (GRB) if the charge can be as large as \\hat{q}˜ ({10}-5{--}{10}-4). The putative short GRB coincident with GW150914 recorded by Fermi GBM may be interpreted with this model. Future joint GW/GRB/FRB searches would lead to a measurement or place a constraint on the charges carried by isolate BHs.

  20. Adverse events of gastric electrical stimulators recorded in the Manufacturer and User Device Experience (MAUDE) Registry.

    PubMed

    Bielefeldt, Klaus

    2017-01-01

    The role of gastric electrical stimulation for patients with refractory symptoms of gastroparesis remains controversial. Open label studies suggest benefit while randomized controlled trials did not demonstrate differences between active and sham intervention. Using a voluntary reporting system of the Federal Drug Administration, we examined the type and frequency of adverse events. We conducted an electronic search of the Manufacturer and User Device Experience (MAUDE) databank using the keyword 'Enterra' for the time between January of 2001 and October of 2015. We abstracted information about the year of stimulator implantation, the year and type of adverse effect, the resulting intervention and outcome if available. A total of 1587 entries described adverse effects related the GES. Only 36 of the reports listed perioperative complications. The vast majority described problems that could be classified as patient concerns, local complications, or system failure. The most common problem related lack or loss of efficacy, followed by pain or complications affecting the pocket site. A subset of 801 reports provided information about the time between system implant and registration of concerns, which gradually declined over time. More than one third (35.7%) of the reported adverse events prompted surgical correction. The number of voluntarily reported adverse events and the high likelihood of repeated surgical interventions clearly demonstrate the potential downside of gastric electrical stimulation. Physicians considering this intervention will need to carefully weigh these risks and include this information when counseling or consenting patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Predicting mining collapse: Superjerks and the appearance of record-breaking events in coal as collapse precursors

    NASA Astrophysics Data System (ADS)

    Jiang, Xiang; Liu, Hanlong; Main, Ian G.; Salje, Ekhard K. H.

    2017-08-01

    The quest for predictive indicators for the collapse of coal mines has led to a robust criterion from scale-model tests in the laboratory. Mechanical collapse under uniaxial stress forms avalanches with a power-law probability distribution function of radiated energy P ˜E-ɛ , with exponent ɛ =1.5 . Impending major collapse is preceded by a reduction of the energy exponent to the mean-field value ɛ =1.32 . Concurrently, the crackling noise increases in intensity and the waiting time between avalanches is reduced when the major collapse is approaching. These latter criteria were so-far deemed too unreliable for safety assessments in coal mines. We report a reassessment of previously collected extensive collapse data sets using "record-breaking analysis," based on the statistical appearance of "superjerks" within a smaller spectrum of collapse events. Superjerks are defined as avalanche signals with energies that surpass those of all previous events. The final major collapse is one such superjerk but other "near collapse" events equally qualify. In this way a very large data set of events is reduced to a sparse sequence of superjerks (21 in our coal sample). The main collapse can be anticipated from the sequence of energies and waiting times of superjerks, ignoring all weaker events. Superjerks are excellent indicators for the temporal evolution, and reveal clear nonstationarity of the crackling noise at constant loading rate, as well as self-similarity in the energy distribution of superjerks as a function of the number of events so far in the sequence Es j˜nδ with δ =1.79 . They are less robust in identifying the precise time of the final collapse, however, than the shift of the energy exponents in the whole data set which occurs only over a short time interval just before the major event. Nevertheless, they provide additional diagnostics that may increase the reliability of such forecasts.

  2. Creating an integrated historical record of extreme particulate air pollution events in Australian cities from 1994 to 2007.

    PubMed

    Johnston, Fay H; Hanigan, Ivan C; Henderson, Sarah B; Morgan, Geoffrey G; Portner, Talia; Williamson, Grant J; Bowman, David M J S

    2011-04-01

    Epidemiological studies of exposure to vegetation fire smoke are often limited by the availability of accurate exposure data. This paper describes a systematic framework for retrospectively identifying the cause of air pollution events to facilitate a long, multicenter analysis of the public health effects of vegetation fire smoke pollution in Australia. Pollution events were statistically defined as any day at or above the 95th percentile of the 24-hr average concentration of particulate matter (PM). These were identified for six cities from three distinct ecoclimatic regions of Australia. The dates of each event were then crosschecked against a range of information sources, including online newspaper archives, government and research agency records, satellite imagery, and aerosol optical thickness measures to identify the cause for the excess particulate pollution. Pollution events occurred most frequently during summer for cities in subtropical and arid regions and during winter for cities in temperate regions. A cause for high PM on 67% of days examined in the city of Sydney was found, and 94% of these could be attributed to landscape fire smoke. Results were similar for cities in other subtropical and arid locations. Identification of the cause of pollution events was much lower in colder temperate regions where fire activity is less frequent. Bushfires were the most frequent cause of extreme pollution events in cities located in subtropical and arid regions of Australia. Although identification of pollution episodes was greatly improved by the use of multiple sources of information, satellite imagery was the most useful tool for identifying bushfire smoke pollution events.

  3. Seawater osmium isotope evidence for a middle Miocene flood basalt event in ferromanganese crust records

    USGS Publications Warehouse

    Klemm, V.; Frank, M.; Levasseur, S.; Halliday, A.N.; Hein, J.R.

    2008-01-01

    Three ferromanganese crusts from the northeast, northwest and central Atlantic were re-dated using osmium (Os) isotope stratigraphy and yield ages from middle Miocene to the present. The three Os isotope records do not show evidence for growth hiatuses. The reconstructed Os isotope-based growth rates for the sections older than 10??Ma are higher than those determined previously by the combined beryllium isotope (10Be/9Be) and cobalt (Co) constant-flux methods, which results in a decrease in the maximum age of each crust. This re-dating does not lead to significant changes to the interpretation of previously determined radiogenic isotope neodymium, lead (Nd, Pb) time series because the variability of these isotopes was very small in the records of the three crusts prior to 10??Ma. The Os isotope record of the central Atlantic crust shows a pronounced minimum during the middle Miocene between 15 and 12??Ma, similar to a minimum previously observed in two ferromanganese crusts from the central Pacific. For the other two Atlantic crusts, the Os isotope records and their calibration to the global seawater curve for the middle Miocene are either more uncertain or too short and thus do not allow for a reliable identification of an isotopic minimum. Similar to pronounced minima reported previously for the Cretaceous/Tertiary and Eocene/Oligocene boundaries, possible interpretations for the newly identified middle Miocene Os isotope minimum include changes in weathering intensity and/or a meteorite impact coinciding with the formation of the No??rdlinger Ries Crater. It is suggested that the eruption and weathering of the Columbia River flood basalts provided a significant amount of the unradiogenic Os required to produce the middle Miocene minimum. ?? 2008 Elsevier B.V.

  4. Seawater osmium isotope evidence for a middle Miocene flood basalt event in ferromanganese crust records

    NASA Astrophysics Data System (ADS)

    Klemm, Veronika; Frank, Martin; Levasseur, Sylvain; Halliday, Alex N.; Hein, James R.

    2008-08-01

    Three ferromanganese crusts from the northeast, northwest and central Atlantic were re-dated using osmium (Os) isotope stratigraphy and yield ages from middle Miocene to the present. The three Os isotope records do not show evidence for growth hiatuses. The reconstructed Os isotope-based growth rates for the sections older than 10 Ma are higher than those determined previously by the combined beryllium isotope (10Be/9Be) and cobalt (Co) constant-flux methods, which results in a decrease in the maximum age of each crust. This re-dating does not lead to significant changes to the interpretation of previously determined radiogenic isotope neodymium, lead (Nd, Pb) time series because the variability of these isotopes was very small in the records of the three crusts prior to 10 Ma. The Os isotope record of the central Atlantic crust shows a pronounced minimum during the middle Miocene between 15 and 12 Ma, similar to a minimum previously observed in two ferromanganese crusts from the central Pacific. For the other two Atlantic crusts, the Os isotope records and their calibration to the global seawater curve for the middle Miocene are either more uncertain or too short and thus do not allow for a reliable identification of an isotopic minimum. Similar to pronounced minima reported previously for the Cretaceous/Tertiary and Eocene/Oligocene boundaries, possible interpretations for the newly identified middle Miocene Os isotope minimum include changes in weathering intensity and/or a meteorite impact coinciding with the formation of the Nördlinger Ries Crater. It is suggested that the eruption and weathering of the Columbia River flood basalts provided a significant amount of the unradiogenic Os required to produce the middle Miocene minimum.

  5. A long record of extreme wave events in coastal Lake Hamana, Japan

    NASA Astrophysics Data System (ADS)

    Boes, Evelien; Yokoyama, Yusuke; Schmidt, Sabine; Riedesel, Svenja; Fujiwara, Osamu; Nakamura, Atsunori; Garrett, Ed; Heyvaert, Vanessa; Brückner, Helmut; De Batist, Marc

    2017-04-01

    Coastal Lake Hamana is located near the convergent tectonic boundary of the Nankai-Suruga Trough, along which the Philippine Sea slab is subducted underneath the Eurasian Plate, giving rise to repeated tsunamigenic megathrust earthquakes (Mw ≥ 8). A good understanding of the earthquake- and tsunami-triggering mechanisms is crucial in order to better estimate the complexity of seismic risks. Thanks to its accommodation space, Lake Hamana may represent a good archive for past events, such as tsunamis and tropical storms (typhoons), also referred to as "extreme wave" events. Characteristic event layers, consisting of sediment entrained by these extreme waves and their backwash, are witnesses of past marine incursions. By applying a broad range of surveying methods (reflection-seismic profiling, gravity coring, piston coring), sedimentological analyses (CT-scanning, XRF-scanning, multi-sensor core logging, grain size, microfossils etc.) and dating techniques (210Pb/137Cs, 14C, OSL, tephrochronology), we attempt to trace extreme wave event deposits in a multiproxy approach. Seismic imagery shows a vertical stacking of stronger reflectors, interpreted to be coarser-grained sheets deposited by highly energetic waves. Systematic sampling of lake bottom sediments along a transect from ocean-proximal to ocean-distal sites enables us to evaluate vertical and lateral changes in stratigraphy. Ocean-proximal, we observe a sequence of eight sandy units separated by silty background sediments, up to a depth of 8 m into the lake bottom. These sand layers quickly thin out and become finer-grained land-inward. Seismic-to-core correlations show a good fit between the occurrence of strong reflectors and sandy deposits, hence confirming presumptions based on acoustic imagery alone. Sand-rich intervals typically display a higher magnetic susceptibility, density and stronger X-ray attenuation. However, based on textural and structural differences, we can make the distinction between

  6. Nanotechnologies for stimulating and recording excitable events in neurons and cardiomyocytes.

    PubMed

    Silva, Gabriel A; Khraiche, Massoud L

    2013-06-01

    Nanotechnologies are engineered materials and devices that have a functional organization in at least one dimension on the nanometer scale, ranging from a few to about 100 nanometers. Functionally, nanotechnologies can display physical, chemical, and engineering properties that go beyond the component building block molecules or structures that make them up. Given such properties and the physical scale involved, these technologies are capable of interacting and interfacing with target cells and tissues in unique ways. One particular emerging application of wide spread interest is the development of nanotechnologies for stimulating and recording excitable cells such as neurons and cardiomyocytes. Such approaches offer the possibility of achieving high density stimulation and recording at sub-cellular resolutions in large populations of cells. This would provide a scale of electrophysiological interactions with excitable cells beyond anything achievable by current existing methods. In this review we introduce the reader to the key concepts and methods associated with nanotechnology and nanoengineering, and discuss the work of some of the key groups developing nanoscale stimulation and recording technologies.

  7. Paleocene-Eocene Paleoclimatic Event Records in the Chicxulub Crater (Yucatan, Gulf of Mexico)

    NASA Astrophysics Data System (ADS)

    Perez-Cruz, L. L.; Fucugauchi, J. U.

    2013-05-01

    Chicxulub crater was formed by an asteroid impact on the Yucatan carbonate platform about 65.5 Ma ago at the Cretaceous/Paleogene (K/Pg) boundary. After crater formation, carbonate deposition gradually covered the structure, preserving a largely undisturbed sedimentary record for the Paleogene. As part of the studies, drilling programs with continuous core recovery have been conducted over the past years. The cores preserve a record of post-impact processes, life recovery in target area, platform evolution and emergence, sea-level changes and the paleoceanographic and paleoclimatic conditions in the region. To contribute to the knowledge of the Paleocene-Eocene warming and changes in oceanic hydrography, we carried out x-ray fluorescence and stable oxygen and carbon isotope studies of the carbonate sections on top of the impact breccias sampled in the Santa Elena and Yaxcopoil-1 boreholes. The Santa Elena borehole is located 110 km radial distance from crater center, outside the crater rim. Yaxcopoil-1 borehole is located 62 km away from crater center in the terrace zone inside the crater rim. The Cenozoic sequence is about 332 m and 796 m thick in the Santa Elena and Yaxcopoil-1 boreholes. The stable isotope records are correlated to data on marine sediment cores from the ocean drilling projects for the Paleocene and Eocene, which permit inferences on the paleoceanographic and paleoclimatic reconstruction as well as additional stratigraphic constraints for the sections. The positive bulk carbon isotope (δ13C) values in the basal Paleocene sediments reflect a return or enhancement of ocean productivity following plankton extinctions following the K/Pg impact. The Paleocene represents a time of global warmth temperatures with low vertical and latitudinal gradients in the oceans, likely resulting from elevated CO2 levels. δ13C values in the Santa Elena borehole show increases between 3 and 4 % by the late Paleocene that decrease to levels prevailing before the K

  8. Expanding neurochemical investigations with multi-modal recording: simultaneous fast-scan cyclic voltammetry, iontophoresis, and patch clamp measurements

    PubMed Central

    Kirkpatrick, D. C.; McKinney, C. J.; Manis, P. B.

    2016-01-01

    Multi-modal recording describes the simultaneous collection of information across distinct domains. Compared to isolated measurements, such studies can more easily determine relationships between varieties of phenomena. This is useful for neurochemical investigations which examine cellular activity in response to changes in the local chemical environment. In this study, we demonstrate a method to perform simultaneous patch clamp measurements with fast-scan cyclic voltammetry (FSCV) using optically isolated instrumentation. A model circuit simulating concurrent measurements was used to predict the electrical interference between instruments. No significant impact was anticipated between methods, and predictions were largely confirmed experimentally. One exception was due to capacitive coupling of the FSCV potential waveform into the patch clamp amplifier. However, capacitive transients measured in whole-cell current clamp recordings were well below the level of biological signals, which allowed the activity of cells to be easily determined. Next, the activity of medium spiny neurons (MSNs) was examined in the presence of an FSCV electrode to determine how the exogenous potential impacted nearby cells. The activities of both resting and active MSNs were unaffected by the FSCV waveform. Additionally, application of an iontophoretic current, used to locally deliver drugs and other neurochemicals, did not affect neighboring cells. Finally, MSN activity was monitored during iontophoretic delivery of glutamate, an excitatory neurotransmitter. Membrane depolarization and cell firing were observed concurrently with chemical changes around the cell resulting from delivery. In all, we show how combined electrophysiological and electrochemical measurements can relate information between domains and increase the power of neurochemical investigations. PMID:27314130

  9. Cold surges and dust events: Establishing the link between the East Asian Winter Monsoon and the Chinese loess record

    NASA Astrophysics Data System (ADS)

    Wyrwoll, Karl-Heinz; Wei, Junhong; Lin, Zhaohui; Shao, Yaping; He, Feng

    2016-10-01

    The Chinese loess/palaeosol succession is one of the most comprehensive and intensively studied archives of Neogene and Quaternary global palaeoclimate events. Its stratigraphic details are widely recognised to indicate close links to the history and function of the East Asian Winter Monsoon (EAWM) - one of the most active components of the Earth's climate system. But the formal meteorological links between the EAWM and dust emission, both in the present day and in the past, have not been established and with it, the veracity of the loess record as an indicator of the EAWM questioned. Here we show that present day major dust events over northern China, while largely occurring during spring, are nevertheless 'conditioned' by the strength of the preceding EAWM. We also demonstrate, for the first time, a close link between the occurrence of dust events and the strength of the EAWM. From these findings, linked to global-scale climate model simulations, we conclude that the Chinese loess succession provides a convincing proxy record of the strength of the East Asian Winter Monsoon.

  10. Event Recording Data Acquisition System and Experiment Data Management System for Neutron Experiments at MLF, J-PARC

    NASA Astrophysics Data System (ADS)

    Nakatani, T.; Inamura, Y.; Moriyama, K.; Ito, T.; Muto, S.; Otomo, T.

    Neutron scattering can be a powerful probe in the investigation of many phenomena in the materials and life sciences. The Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex (J-PARC) is a leading center of experimental neutron science and boasts one of the most intense pulsed neutron sources in the world. The MLF currently has 18 experimental instruments in operation that support a wide variety of users from across a range of research fields. The instruments include optical elements, sample environment apparatus and detector systems that are controlled and monitored electronically throughout an experiment. Signals from these components and those from the neutron source are converted into a digital format by the data acquisition (DAQ) electronics and recorded as time-tagged event data in the DAQ computers using "DAQ-Middleware". Operating in event mode, the DAQ system produces extremely large data files (˜GB) under various measurement conditions. Simultaneously, the measurement meta-data indicating each measurement condition is recorded in XML format by the MLF control software framework "IROHA". These measurement event data and meta-data are collected in the MLF common storage and cataloged by the MLF Experimental Database (MLF EXP-DB) based on a commercial XML database. The system provides a web interface for users to manage and remotely analyze experimental data.

  11. Low Amplitude of Geomagnetic Secular Variations Recorded in Traps of the Southern Siberian Platform: Very Fast Emplacement or Regional Remagnetization?

    NASA Astrophysics Data System (ADS)

    Veselovskiy, R. V.; Latyshev, A. V.; Pavlov, V. E.

    2011-12-01

    We have studied the lowest part of the Permo-Triassic Siberian trap sequence which is located in the middle course of the Angara river (Southern Siberia). This sequenced is composed by 200m thick volcanoclastic rocks (tuffs with bombs of different composition) and includes numerous mafic subvolcanic bodies (dykes and sills). Altogether more than 20 sites representing tuffs, bombs, dykes and sills stretched along the valley of the Angara river over the distance more than 30 km have been sampled and studied. Obtained site mean paleomagnetic directions are tightly grouped, showing very lower scatter. Taking into account that amplitude of geomagnetic secular variation at the P-T boundary was about of same order as in Late Cenozoic (Pavlov et al., 2011) this lower scatter can be either a sequence of very fast traps emplacement which could have disastrous environmental impact or a result of subsequent regional remagnetization. The only geological event in the region which seems to be capable to cause this remagnetization is emplacement of Early Triassic sills in nearby areas. In such the case we should expect that mean paleomagnetic directions from these sills will be very close to these ones obtained from site presented in this report. We present results of paleomagnetic studies of these sills and make a choice in favor of one of discussed options. This work was supported by grants NSF EAR 0807585 ("The Siberian Traps and end-Permian extinction") and RFBR 09-05-01180, 10-05-00557.

  12. Archaeology of Archaea: geomicrobiological record of Pleistocene thermal events concealed in a deep-sea subseafloor environment.

    PubMed

    Inagaki, F; Takai, K; Komatsu, T; Kanamatsu, T; Fujioka, K; Horikoshi, K

    2001-12-01

    A record of the history of the Earth is hidden in the Earth's crust, like the annual rings of an old tree. From very limited records retrieved from deep underground, one can infer the geographical, geological, and biological events that occurred throughout Earth's history. Here we report the discovery of vertically shifted community structures of Archaea in a typical oceanic subseafloor core sample (1410 cm long) recovered from the West Philippine Basin at a depth of 5719 m. Beneath a surface community of ubiquitous deep-sea archaea (marine crenarchaeotic group I; MGI), an unusual archaeal community consisting of extremophilic archaea, such as extreme halophiles and hyperthermophiles, was present. These organisms could not be cultivated, and may be microbial relicts more than 2 million years old. Our discovery of archaeal rDNA in this core sample, probably associated with the past terrestrial volcanic and submarine hydrothermal activities surrounding the West Philippine Basin, serves as potential geomicrobiological evidence reflecting novel records of geologic thermal events in the Pleistocene period concealed in the deep-sea subseafloor.

  13. On the reliability of geomagnetic excursions and short events recorded in Central Mexico: a cautionary note (Invited)

    NASA Astrophysics Data System (ADS)

    Gogichaishvili, A.

    2013-12-01

    Recognition of brief polarity excursions as a part of the Earth's paleomagnetic field behavior has developed during the last two decades together with astrochronological calibration of the polarity timescale. During this time, numerous geomagnetic excursions have been discovered in the previously believed stable Brunhes and Matuyama chrons. Volcanic rocks allow a reliable and instantaneous record of the Earth's magnetic field by means of the acquisition of thermoremanent magnetisation, although being tied to volcanic eruptions, they provide a discontinuous record. Nevertheless, because volcanic rocks are in principle able to offer a more faithful though instantaneous image of the Earth's magnetic field, the paleomagnetic study of lava flows can be of major interest for the knowledge of characteristics and variations of the ancient geomagnetic field. In order to be useful, this kind of paleomagnetic studies needs to be supplemented by precise radiometric dates. The Trans-Mexican Volcanic belt with several thousands of volcanic build-ups seems to be one of the most adequate unit for paleomagnetic targets. There is probably no other Plio-Quaternary volcanic field in the world displaying such a large number of monogenetic (mainly) volcanoes and it can be said that in this respect it is a unique feature. Recently, many Ar-Ar dated Bruhnes and Matuyama lava flows were suspected to record geomagnetic excursions and short events. Here, we analyze and discuss the reliability of such events and their geomagnetic significances.

  14. An optical age chronology of late Quaternary extreme fluvial events recorded in Ugandan dambo soils

    USGS Publications Warehouse

    Mahan, S.A.; Brown, D.J.

    2007-01-01

    There is little geochonological data on sedimentation in dambos (seasonally saturated, channel-less valley floors) found throughout Central and Southern Africa. Radiocarbon dating is problematic for dambos due to (i) oxidation of organic materials during dry seasons; and (ii) the potential for contemporary biological contamination of near-surface sediments. However, for luminescence dating the equatorial site and semi-arid climate facilitate grain bleaching, while the gentle terrain ensures shallow water columns, low turbidity, and relatively long surface exposures for transported grains prior to deposition and burial. For this study, we focused on dating sandy strata (indicative of high-energy fluvial events) at various positions and depths within a second-order dambo in central Uganda. Blue-light quartz optically stimulated luminescences (OSL) ages were compared with infrared stimulated luminescence (IRSL) and thermoluminescence (TL) ages from finer grains in the same sample. A total of 8 samples were dated, with 6 intervals obtained at ???35, 33, 16, 10.4, 8.4, and 5.9 ka. In general, luminescence ages were stratigraphically, geomorphically and ordinally consistent and most blue-light OSL ages could be correlated with well-dated climatic events registered either in Greenland ice cores or Lake Victoria sediments. Based upon OSL age correlations, we theorize that extreme fluvial dambo events occur primarily during relatively wet periods, often preceding humid-to-arid transitions. The optical ages reported in this study provide the first detailed chronology of dambo sedimentation, and we anticipate that further dambo work could provide a wealth of information on the paleohydrology of Central and Southern Africa. ?? 2006 Elsevier Ltd. All rights reserved.

  15. Adverse Events in Korean Traditional Medicine Hospitals: A Retrospective Medical Record Review.

    PubMed

    Hwang, Jee-In; Kim, Jinsung; Park, Jae-Woo

    2015-05-21

    Traditional medicine has been used worldwide in recent decades. The aim of this study was to determine the incidence of adverse events (AEs) in traditional medicine hospitals and investigate patient and health-care utilization factors associated with AE occurrence. A 2-stage review of 1152 randomly sampled charts in 2 teaching Korean traditional medicine hospitals was conducted. Three physicians and a quality improvement specialist identified AE occurrence, severity, and preventability using the Global Trigger Tool (Appendix 1, Supplemental Digital Content, http://links.lww.com/JPS/A19). Two traditional Korean medicine professors validated the findings. Logistic regression analysis was performed to determine factors associated with AE occurrence. One hundred twenty-two admissions (10.6%) had at least one AE (7.39 events per 1000 patient days and 14.5 events per 100 admissions). Among 167 AEs, 73.7% were mild and 70.7% were judged preventable. Procedure-related AEs were most common. After considering other patient and health-care utilization characteristics, factors associated with AE occurrence were altered mental status on admission (OR, 3.86; 95% confidence interval [CI], 1.20-12.44), use of various traditional medicine therapies (OR, 1.69; 95% CI, 1.32-2.15), length of stay (OR, 1.02; 95% CI, 1.01-1.03), and number of unique triggers (OR, 6.35; 95% CI, 4.54-8.89). Approximately 11% of inpatients in traditional medicine hospitals experienced AEs. Because patients have a higher risk of AEs, special attention should be paid to those with altered mental status on admission, receiving various traditional medicine therapies, staying for a longer period, and having various positive triggers.

  16. Second pain event related potentials to argon laser stimuli: recording and quantification.

    PubMed Central

    Arendt-Nielsen, L

    1990-01-01

    A non-invasive technique for quantification of argon laser induced burning second pain (C-fibre) is suggested. Using frequency analysis event related responses to burning pain can be detected in the EEG interval 1-2 seconds after laser stimulation. When the laser stimulus induced a burning pain perception, the power from 0.5-2.5 Hz of the EEG interval 1-2 seconds after stimulation differed significantly from the power calculated from the same time interval when no burning pain was perceived. PMID:2351970

  17. Late Holocene record of sedimentologic and paleooceanographic events in western Guaymas Basin, Gulf of California

    NASA Astrophysics Data System (ADS)

    McGann, M.; Paull, C. K.; Herguera, J. C.; Barron, J. A.; Gwiazda, R.; Anderson, K.; Lundsten, E. M.; Edwards, B. D.; Caress, D. W.

    2015-12-01

    Transects of ≤1.5 m-long vibracores obtained with MBARI's ROV Doc Ricketts reveal late Holocene sedimentologic and paleooceanographic events in western Guaymas Basin, Gulf of California (GOC) (~26.87°N, 111.338°W). Cores were located where layered near-seafloor sediments and subtle bedforms occur in 1793 to 1863 m water depths on the SW flank of the basin using detailed bathymetry and chirp profiles. Color banding was observed in the cores and gamma-density, XRF, grain size, and stable isotope data show that most of the banding is attributed to distal deposition from two turbidities. Distinctive white bands ~4 cm thick are present in three cores dispersed across ~300 m. The white bands are diatom oozes composed primarily of Thalassiothrix longissima as well as lesser abundances of Fragilariopsis doliolus and are probably a result of aggregations of Thalassiothrix-dominated mats that settle through the water column and accumulate on the seafloor. An AMS14C date taken ~3 cm above the white band in one core suggests this event occurred shortly before cal AD 1290±30. The core sites were most likely located beneath an important oceanographic front between nutrient-rich and oligotrophic water masses, probably as the result of well-mixed upper intermediate and surface waters in the mid-GOC and better-stratified tropical waters to the south. This implies the existence of a deeper mixed layer to the N in the mid GOC region most likely controlled by equatorial La Niña events fueled by stronger and more persistent NW winds along the GOC. A substantial reduction in diatom abundance evident by low specimen counts and lack of white bands following this mat-forming event seem to correlate with an abrupt decline in biosiliceous productivity and increases in the abundance of tropical diatoms and silicoflagellates in core MD02-2517 (887 m water depth; western Guaymas Basin slope) at the end of the Medieval Climate Anomaly and transition to the Little Ice Age (~AD 1200-1300).

  18. The earliest molecular response to stretch of insect flight muscle as revealed by fast X-ray diffraction recording

    PubMed Central

    Iwamoto, Hiroyuki

    2017-01-01

    Small insects drive their flight muscle at frequencies up to 1,000 Hz. This remarkable ability owes to the mechanism of stretch activation. However, it remains unknown as to what sarcomeric component senses the stretch and triggers the following force generation. Here we show that the earliest structural change after a step stretch is reflected in the blinking of the 111 and 201 reflections, as observed in the fast X-ray diffraction recording from isolated bumblebee flight muscle fibers. The same signal has also been observed in live bumblebee. We demonstrate that (1) the signal responds almost concomitantly to a quick step stretch, (2) the signal grows with increasing calcium levels as the stretch-activated force does, and (3) a full 3-dimensional model demonstrates that the signal is maximized when objects having a 38.7-nm actin periodicity travel by ~20 nm along the filament axis. This is the expected displacement if myosin heads are loosely associated with actin target zones (where actin monomers are favorably oriented), and are dragged by a 1.3% stretch, which effectively causes stretch-induced activation. These results support and strengthen our proposal that the myosin head itself acts as the stretch sensor, after calcium-induced association with actin in a low-force form. PMID:28176871

  19. Impulse radio ultra wideband wireless transmission of dopamine concentration levels recorded by fast-scan cyclic voltammetry.

    PubMed

    Ebrazeh, Ali; Bozorgzadeh, Bardia; Mohseni, Pedram

    2015-01-01

    This paper demonstrates the feasibility of utilizing impulse radio ultra wideband (IR-UWB) signaling technique for reliable, wireless transmission of dopamine concentration levels recorded by fast-scan cyclic voltammetry (FSCV) at a carbon-fiber microelectrode (CFM) to address the problem of elevated data rates in high-channel-count neurochemical monitoring. Utilizing an FSCV-sensing chip fabricated in AMS 0.35μm 2P/4M CMOS, a 3-5-GHz, IR-UWB transceiver (TRX) chip fabricated in TSMC 90nm 1P/9M RF CMOS, and two off-chip, miniature, UWB antennae, wireless transfer of pseudo-random binary sequence (PRBS) data at 50Mbps over a distance of <;1m is first shown with bit-error rates (BER) <; 10(-3). Further, IR-UWB wireless transmission of dopamine concentration levels prerecorded with FSCV at a CFM during flow injection analysis (FIA) is also demonstrated with transmitter (TX) power dissipation of only ~4.4μW from 1.2V, representing two orders of magnitude reduction in TX power consumption compared to that of a conventional frequency-shift-keyed (FSK) link operating at ~433MHz.

  20. NEV2lkit: a new open source tool for handling neuronal event files from multi-electrode recordings.

    PubMed

    Bongard, Markus; Micol, Daniel; Fernández, Eduardo

    2014-06-01

    The analysis and discrimination of action potentials, or "spikes", is a central issue to systems neuroscience research. Here we introduce a free open source software for the analysis and discrimination of neural spikes based on principal component analysis and different clustering algorithms. The main objective is to supply a friendly user interface that links the experimental data to a basic set of routines for analysis, visualization and classification of spikes in a consistent framework. The tool has been tested on artificial data sets, on multi-electrode extracellular recordings from ganglion cell populations in isolated superfused mouse, rabbit and turtle retinas, and on electrophysiological recordings from mouse visual cortex. Our results show that NEV2lkit is very reliable and able to satisfy the experimental demands in terms of accuracy, efficiency and consistency across experiments. It performs fast unit sorting in single or multiple experiments and allows the extraction of spikes from over large time intervals in continuously recorded data streams. The tool is implemented in C++ and runs cross-platform on Linux, OS X and Windows systems. To facilitate the adaptation and extension as well as the addition of new routines, tools and algorithms for data analysis, the source code, binary distributions for different operating systems and documentation are all freely available at http://nev2lkit.sourceforge.net .

  1. Apparatus for recording emissions from a rapidly generated plasma from a single plasma producing event

    DOEpatents

    Tan, Tai Ho; Williams, Arthur H.

    1985-01-01

    An optical fiber-coupled detector visible streak camera plasma diagnostic apparatus. Arrays of optical fiber-coupled detectors are placed on the film plane of several types of particle, x-ray and visible spectrometers or directly in the path of the emissions to be measured and the output is imaged by a visible streak camera. Time and spatial dependence of the emission from plasmas generated from a single pulse of electromagnetic radiation or from a single particle beam burst can be recorded.

  2. Apparatus for recording emissions from a rapidly generated plasma from a single plasma producing event

    DOEpatents

    Tan, T.H.; Williams, A.H.

    An optical fiber-coupled detector visible streak camera plasma diagnostic apparatus. Arrays of optical fiber-coupled detectors are placed on the film plane of several types of particle, x-ray and visible spectrometers or directly in the path of the emissions to be measured and the output is imaged by a visible streak camera. Time and spatial dependence of the emission from plasma generated from a single pulse of electromagnetic radiation or from a single particle beam burst can be recorded.

  3. JPL, NASA and the Historical Record: Key Events/Documents in Lunar and Mars Exploration

    NASA Technical Reports Server (NTRS)

    Hooks, Michael Q.

    1999-01-01

    This document represents a presentation about the Jet Propulsion Laboratory (JPL) historical archives in the area of Lunar and Martian Exploration. The JPL archives documents the history of JPL's flight projects, research and development activities and administrative operations. The archives are in a variety of format. The presentation reviews the information available through the JPL archives web site, information available through the Regional Planetary Image Facility web site, and the information on past missions available through the web sites. The presentation also reviews the NASA historical resources at the NASA History Office and the National Archives and Records Administration.

  4. Correspondence between a noisy sample-space-reducing process and records in correlated random events

    NASA Astrophysics Data System (ADS)

    Yadav, Avinash Chand

    2017-09-01

    We study survival time statistics in a noisy sample-space-reducing (SSR) process. Our simulations suggest that both the mean and standard deviation scale as ˜N /Nλ , where N is the system size and λ is a tunable parameter that characterizes the process. The survival time distribution has the form PN(τ ) ˜N-θJ (τ /Nθ) , where J is a universal scaling function and θ =1 -λ . Analytical insight is provided by a conjecture for the equivalence between the survival time statistics in the noisy SSR process and the record statistics in a correlated time series modeled as a drifted random walk with Cauchy distributed jumps.

  5. Amazon Paleofires Records: Comparison Between Land Use Change and Palaeoclimatic Events

    NASA Astrophysics Data System (ADS)

    Cordeiro, R. C.; Turcq, B.; Moreira, L. S.; Rodrigues, R. D. A.; Simões Filho, F. L.; Martins, G. S.; Santos, A. B.; Barbosa, M.; da Conceição, M. C. G.; Rodrigues, R. D. C.; Evangelista, H.; Moreira-Turcq, P. F.; Penido, Y. P.; Sifeddine, A.; Seoane, J.

    2014-12-01

    Interpreting the geological record of Amazon biomass combustion requires comparing charcoal accumulation rates in various biomes at different time scales. Charcoal accumulation rates, a proxy for palaeofire records, were obtained in sediment cores from Amazon lakes surrounded by several vegetation types and from a reservoir in an intense land use change region. The records presented in this study were obtained in the following areas i) a reservoir in Alta Floresta region (northern Mato Grosso State); ii) Lago do Saci (southern Pará State), a lake close to Alta Floresta and located at the southern border of Pará State; iii) a bog in an ecotone area in the Humaitá region (southern Amazonas State); iv) lakes in lateritic iron crust of the Carajás Hills (southeastern Pará State); v) Lago Comprido, a floodplain lake close to the Amazon River and surrounded by tropical rain forest (Monte Alegre, Pará State; vi) Lagoa da Pata in the Morro dos Seis Lagos alkaline complex (São Gabriel da Cachoeira, Amazonas State) and vii) Lago Caracaranã, a secluded lake in the northern Amazon cerrado (Roraima State). The highest charcoal accumulation rates were observed for modern records related to an intense change in land use at Alta Floresta, which had no precedent during the Holocene history of the Amazon. High charcoal accumulation rates that were observed in the Carajás region during low lake level phases in the Amazon in the mid-Holocene were comparable to those at the onset of the human settlement in Alta Floresta region. An increase in charcoal accumulation rate was observed in the late Holocene when the lake level was high, suggesting an interaction between climates and human presence. Low charcoal accumulation rates are typical of modern high rainfall environments, as observed in Lagoa da Pata where the environment is not susceptible to occurrences of wildfires even during relatively drier climatic phases. Low charcoal accumulation rates also exist in the relatively

  6. Iridium abundance measurements across bio-event horizons in the fossil record

    SciTech Connect

    Orth, C.J.; Attrep, M. Jr.; Quintana, L.R. )

    1989-01-01

    Geochemical measurements have been performed on thousands of rock samples collected across bio-event horizons using Instrumental Neutron Activation Analysis (INAA) for about 40 common and trace elements and radiochemical isolation procedures for Ir. On selected samples, Os, Pt and Au were also radiochemically determined. These studies have encompassed the time interval from the Precambrian-Cambrian transition to the Late Eocene impact (microspherule) horizons. Our early work strengthened the Alvarez impact hypothesis by finding the Ir (PGE) anomaly at the K-T boundary in continental sedimentary sequences. In collaborations with paleontologists, weak to moderately string Ir anomalies have been discovered at the Frasnian-Famennian boundary in Australia, in the Early Mississippian of Oklahoma, at the Mississipian-Pennsylvanian boundary of Oklahoma and Texas, and in the Late Cenomanian throughout the western interior of North America and on the south coast of England to date. We have found no compelling evidence for an impact related cause for these anomalies although PGE impact signatures in the two Late Cenomanian anomalies could be masked by the strong terrestrial mafic to ultramafic overprint. Thus far, our evidence for extinction events older than the terminal Cretaceous does not support recent hypotheses which suggest that impacts from cyclic swarms of comets in the inner Solar system were responsible for the periodic mass extinctions. 50 refs., 7 figs., 3 tabs.

  7. Constraints on early events in Martian history as derived from the cratering record

    SciTech Connect

    Barlow, N.G. )

    1990-08-30

    The shapes and densities of crater size-frequency distribution curves are used to constrain two major events early in Martian history: termination of high obliteration rates and viability of the multiple impact origin of the crustal dichotomy. Distribution curves of fresh craters superposed on uplands, intercrater plains, and ridged plains display shapes and densities indicative of formation prior to the end of heavy bombardment. This observation correlates with other geologic evidence, suggesting a major change in the erosional regime following the last major basin size impact (i.e., Argrye). In addition, the multisloped nature of the curves supports the idea that the downturn in the crater size-frequency distribution curves reflects the size-frequency distribution of the impactors rather than being the result of erosion. The crustal dichotomy formed prior to the heavy bombardment intermediate epoch based on distribution curves of knobby terrain; if the dichotomy resulted from a single gigantic impact, this observation places constraints on when this event happened. An alternate theory for dichotomy formation, the multiple-impact basin idea, is questioned: since distribution curves of large basins as well as heavy bombardment era units are not represented by a {minus}3 differential power law function, this study finds fewer basins missing on Mars compare to the Moon and Mercury than previously reported. The area covered by these missing basins is less than that covered the northern plains.

  8. Sedimentary records of metal speciation in the Yangtze Estuary: role of hydrological events.

    PubMed

    Feng, Chenghong; Zhao, Shou; Wang, Dongxin; Niu, Junfeng; Shen, Zhenyao

    2014-07-01

    Chemical speciation of Al, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb and Zn in two typical (210)Pb-dated sediment cores (i.e., the CJ03 site and CJ06 site) in the Yangtze Estuary was investigated to reveal their different responses to upstream hydrological events. Cluster analysis and correlation analysis (CA) demonstrated that the CJ03 site, which is located in the main river channel, experienced significant influences from river hydrology. Specifically, metals in liable fractions (exchangeable, carbonate, reducible and organic fractions) were sensitive to water fluxes, while conservative fractions (residual fractions) have higher affinity with sediment inputs. By comparison, the CJ06 site in shoal correlated better with total organic carbon (TOC), and was influenced more by the surrounding cities. Evidently decreased sediment discharge and their fluctuated size composition and varied metal concentrations accorded well with the time when the impoundment of dams and disastrous flood occurred. The transformation of metals in liable speciation into conservative phases reflected the intercepting role of dams. Metals in the reducible and organic fractions were significantly affected by the varied redox conditions caused by hydrological events.

  9. The lacustrine record of the Dan-C2 hyperthermal event of the Boltysh Impact Crater, Ukraine

    NASA Astrophysics Data System (ADS)

    Ebinghaus, Alena; Jolley, David W.

    2015-04-01

    Vegetation response to rapid climate change in the geological record is a fundamental element in our understanding of ancient environments; however, the relationships between climate change, plant ecosystems and geological processes are still not fully understood. The filling of the K/Pg Boltysh meteorite crater, Ukraine, comprise a complete terrestrial sedimentological, palynological and δ13C record of the negative carbon isotope excursion of the early Danian hyperthermal episode. The meteorite impact formed a crater of c. 24 km in diameter at c. 65.2 Ma, which was filled with more than 500 m of organic- and fossil-rich claystones, siltstones and marls, interbedded with sandstones and less frequently gravelly sandstones. The sedimentary succession indicates a deep lake setting that was characterised by fluvial input of reworked basement material via a marginal delta system. Palynological investigations indicate a post-impact early- to mid-successional flora followed by a barren zone which coincides with the age of the Chicxulub impact and therefore argues for a series of impact events at the K/Pg boundary. This barren zone was succeeded by a fern spike marking an initial plant re-colonization. The following palynoflora suggests moisture availability oscillations (MAOs) reflecting 41 k.y. obliquity cycles, which can be correlated with lithological fluctuations during lake evolution. The aim is to conduct a detailed, complete facies analysis, and to correlate lake evolutionary aspects with climatic oscillations and vegetation change within the catchment area. This study will be compared with records of similar hyperthermal events, such as the Paleocene-Eocene Thermal Maximum (PETM) in the Western Interior in North America. This integrated approach will help to better understand the controlling factors of global warming events, and their effects on ancient sedimentary environments and ecosystems.

  10. Theoretical insight into the photodegradation of a disulfide bridged cyclic tetrapeptide in solution and subsequent fast unfolding-refolding events.

    PubMed

    Chen, Xuebo; Gao, Lianghui; Fang, Weihai; Phillips, David Lee

    2010-04-22

    We report the photoinduced peptide bond (C-N) of an amide unit and S-S bond fission mechanisms of the cyclic tetrapeptide [cyclo(Boc-Cys-Pro-Aib-Cys-OMe)] in methanol solvent by using high-level CASSCF/CASPT2/Amber quantum mechanical/molecular mechanical (QM/MM) calculations. The subsequent energy transport and unfolding-refolding events are characterized by using a semiempirical QM/MM molecular dynamics (MD) simulation methodology that is developed in the present work. In the case of high-energy excitation with <193 nm light, the tetrapeptide molecule in the (1)n pi* surface overcomes two barriers with approximately 10.0 kcal/mol, respectively, and uses energy consumption for breaking the hydrogen bond as well as the N-C bond in the amide unit, ultimately leading to the ground state via a conical intersection of CI (S(NP)/S(0)) by structural changes of an increased N-C distance and a O-C-C angle in the amide unit (a two-dimensional model of the reaction coordinates). Following this point, relaxation to a hot molecule with its original structure in the ground state is the predominant decay channel. A large amount of heat (approximately 110.0 kcal/mol) is initially accumulated in the region of the targeted point of the photoexcitation, and more than 60% of the heat is rapidly dissipated into the solvent on the femtosecond time scale. The relatively slower propagation of heat along the peptide backbone reaches a phase of equilibration within 3 ps. A 300 nm photon of light initiates the relaxation along the repulsive S(sigma sigma)((1)sigma sigma*) state and this decays to the CI (S(sigma sigma)/S(0)) in concomitance with the separation of the disulfide bond. Once cysteinyl radicals are generated, the polar solvent of methanol molecules rapidly diffuses around the radicals, forming a solvent cage and reducing the possibility of close contact in a physical sense. The fast unfolding-refolding event is triggered by S-S bond fission and powered by dramatic thermal motion

  11. First record of single event upset on the ground, Cray-1 computer memory at Los Alamos in 1976

    SciTech Connect

    Michalak, Sarah E; Quinn, Heather M; Grider, Gary A; Iwanchuk, Paul N; Morrison, John F; Wender, Stephen A; Normand, Eugene; Wert, Jerry L; Johnson, Steve

    2010-01-01

    Records of bit flips in the Cray-1 computer installed at Los Alamos in 1976 lead to an upset rate in the Cray-1 's bipolar SRAMs that correlates with the SEUs being induced by the atmospheric neutrons. In 1976 the Cray Research Company delivered its first supercomputer, the Cray-1, installing it at Los Alamos National Laboratory. Los Alamos had competed with the Lawrence Livermore National Laboratory for the Cray-1 and won, reaching an agreement with Seymour Cray to install the machine for a period of six months for free, after which they could decide whether to buy, lease or return it. As a result, Los Alamos personnel kept track of the computer reliability and performance and so we know that during those six months of operation, 152 memory parity errors were recorded. The computer memory consisted of approximately 70,000 1Kx1 bipolar ECL static RAMs, the Fairchild 10415. What the Los Alamos engineers didn't know is that those bit flips were the result of single event upsets (SEUs) caused by the atmospheric neutrons. Thus, these 152 bit flips were the first recorded SEUs on the earth, and were observed 2 years before the SEUs in the Intel DRAMs that had been found by May and Woods in 1978. The upsets in the DRAMs were shown to have been caused by alpha particles from the chip packaging material. In this paper we will demonstrate that the Cray-1 bit flips, which were found through the use of parity bits in the Cray-1, were likely due to atmospheric neutrons. This paper will follow the same approach as that of the very first paper to demonstrate single event effects, which occurred in satellite flip-flop circuits in 1975. The main difference is that in the four events that occurred over the course of 17 satellite years of operation were shown to be due to single event effects just a few years after those satellite anomalies were recorded. In the case of the Cray-1 bit flips, there has been a delay of more than 30 years between the occurrence of the bit flips and the

  12. Event-related potentials in clinical research: guidelines for eliciting, recording, and quantifying mismatch negativity, P300, and N400.

    PubMed

    Duncan, Connie C; Barry, Robert J; Connolly, John F; Fischer, Catherine; Michie, Patricia T; Näätänen, Risto; Polich, John; Reinvang, Ivar; Van Petten, Cyma

    2009-11-01

    This paper describes recommended methods for the use of event-related brain potentials (ERPs) in clinical research and reviews applications to a variety of psychiatric and neurological disorders. Techniques are presented for eliciting, recording, and quantifying three major cognitive components with confirmed clinical utility: mismatch negativity (MMN), P300, and N400. Also highlighted are applications of each of the components as methods of investigating central nervous system pathology. The guidelines are intended to assist investigators who use ERPs in clinical research, in an effort to provide clear and concise recommendations and thereby to standardize methodology and facilitate comparability of data across laboratories.

  13. Cu isotopes in marine black shales record the Great Oxidation Event

    PubMed Central

    Rodríguez, Nathalie P.; Partin, Camille A.; Andersson, Per; Weiss, Dominik J.; El Albani, Abderrazak; Rodushkin, Ilia; Konhauser, Kurt O.

    2016-01-01

    The oxygenation of the atmosphere ∼2.45–2.32 billion years ago (Ga) is one of the most significant geological events to have affected Earth’s redox history. Our understanding of the timing and processes surrounding this key transition is largely dependent on the development of redox-sensitive proxies, many of which remain unexplored. Here we report a shift from negative to positive copper isotopic compositions (δ65CuERM-AE633) in organic carbon-rich shales spanning the period 2.66–2.08 Ga. We suggest that, before 2.3 Ga, a muted oxidative supply of weathering-derived copper enriched in 65Cu, along with the preferential removal of 65Cu by iron oxides, left seawater and marine biomass depleted in 65Cu but enriched in 63Cu. As banded iron formation deposition waned and continentally sourced Cu became more important, biomass sampled a dissolved Cu reservoir that was progressively less fractionated relative to the continental pool. This evolution toward heavy δ65Cu values coincides with a shift to negative sedimentary δ56Fe values and increased marine sulfate after the Great Oxidation Event (GOE), and is traceable through Phanerozoic shales to modern marine settings, where marine dissolved and sedimentary δ65Cu values are universally positive. Our finding of an important shift in sedimentary Cu isotope compositions across the GOE provides new insights into the Precambrian marine cycling of this critical micronutrient, and demonstrates the proxy potential for sedimentary Cu isotope compositions in the study of biogeochemical cycles and oceanic redox balance in the past. PMID:27091980

  14. Cu isotopes in marine black shales record the Great Oxidation Event.

    PubMed

    Chi Fru, Ernest; Rodríguez, Nathalie P; Partin, Camille A; Lalonde, Stefan V; Andersson, Per; Weiss, Dominik J; El Albani, Abderrazak; Rodushkin, Ilia; Konhauser, Kurt O

    2016-05-03

    The oxygenation of the atmosphere ∼2.45-2.32 billion years ago (Ga) is one of the most significant geological events to have affected Earth's redox history. Our understanding of the timing and processes surrounding this key transition is largely dependent on the development of redox-sensitive proxies, many of which remain unexplored. Here we report a shift from negative to positive copper isotopic compositions (δ(65)CuERM-AE633) in organic carbon-rich shales spanning the period 2.66-2.08 Ga. We suggest that, before 2.3 Ga, a muted oxidative supply of weathering-derived copper enriched in (65)Cu, along with the preferential removal of (65)Cu by iron oxides, left seawater and marine biomass depleted in (65)Cu but enriched in (63)Cu. As banded iron formation deposition waned and continentally sourced Cu became more important, biomass sampled a dissolved Cu reservoir that was progressively less fractionated relative to the continental pool. This evolution toward heavy δ(65)Cu values coincides with a shift to negative sedimentary δ(56)Fe values and increased marine sulfate after the Great Oxidation Event (GOE), and is traceable through Phanerozoic shales to modern marine settings, where marine dissolved and sedimentary δ(65)Cu values are universally positive. Our finding of an important shift in sedimentary Cu isotope compositions across the GOE provides new insights into the Precambrian marine cycling of this critical micronutrient, and demonstrates the proxy potential for sedimentary Cu isotope compositions in the study of biogeochemical cycles and oceanic redox balance in the past.

  15. Cu isotopes in marine black shales record the Great Oxidation Event

    NASA Astrophysics Data System (ADS)

    Fru, Ernest Chi; Rodríguez, Nathalie P.; Partin, Camille A.; Lalonde, Stefan V.; Andersson, Per; Weiss, Dominik J.; El Albani, Abderrazak; Rodushkin, Ilia

    2016-05-01

    The oxygenation of the atmosphere ˜2.45-2.32 billion years ago (Ga) is one of the most significant geological events to have affected Earth's redox history. Our understanding of the timing and processes surrounding this key transition is largely dependent on the development of redox-sensitive proxies, many of which remain unexplored. Here we report a shift from negative to positive copper isotopic compositions (δ65CuERM-AE633) in organic carbon-rich shales spanning the period 2.66-2.08 Ga. We suggest that, before 2.3 Ga, a muted oxidative supply of weathering-derived copper enriched in 65Cu, along with the preferential removal of 65Cu by iron oxides, left seawater and marine biomass depleted in 65Cu but enriched in 63Cu. As banded iron formation deposition waned and continentally sourced Cu became more important, biomass sampled a dissolved Cu reservoir that was progressively less fractionated relative to the continental pool. This evolution toward heavy δ65Cu values coincides with a shift to negative sedimentary δ56Fe values and increased marine sulfate after the Great Oxidation Event (GOE), and is traceable through Phanerozoic shales to modern marine settings, where marine dissolved and sedimentary δ65Cu values are universally positive. Our finding of an important shift in sedimentary Cu isotope compositions across the GOE provides new insights into the Precambrian marine cycling of this critical micronutrient, and demonstrates the proxy potential for sedimentary Cu isotope compositions in the study of biogeochemical cycles and oceanic redox balance in the past.

  16. Selenium isotopes record extensive marine suboxia during the Great Oxidation Event.

    PubMed

    Kipp, Michael A; Stüeken, Eva E; Bekker, Andrey; Buick, Roger

    2017-01-31

    It has been proposed that an "oxygen overshoot" occurred during the early Paleoproterozoic Great Oxidation Event (GOE) in association with the extreme positive carbon isotopic excursion known as the Lomagundi Event. Moreover, it has also been suggested that environmental oxygen levels then crashed to very low levels during the subsequent extremely negative Shunga-Francevillian carbon isotopic anomaly. These redox fluctuations could have profoundly influenced the course of eukaryotic evolution, as eukaryotes have several metabolic processes that are obligately aerobic. Here we investigate the magnitude of these proposed oxygen perturbations using selenium (Se) geochemistry, which is sensitive to redox transitions across suboxic conditions. We find that δ(82/78)Se values in offshore shales show a positive excursion from 2.32 Ga until 2.1 Ga (mean +1.03 ± 0.67‰). Selenium abundances and Se/TOC (total organic carbon) ratios similarly show a peak during this interval. Together these data suggest that during the GOE there was pervasive suboxia in near-shore environments, allowing nonquantitative Se reduction to drive the residual Se oxyanions isotopically heavy. This implies O2 levels of >0.4 μM in these settings. Unlike in the late Neoproterozoic and Phanerozoic, when negative δ(82/78)Se values are observed in offshore environments, only a single formation, evidently the shallowest, shows evidence of negative δ(82/78)Se. This suggests that there was no upwelling of Se oxyanions from an oxic deep-ocean reservoir, which is consistent with previous estimates that the deep ocean remained anoxic throughout the GOE. The abrupt decline in δ(82/78)Se and Se/TOC values during the subsequent Shunga-Francevillian anomaly indicates a widespread decrease in surface oxygenation.

  17. Selenium isotopes record extensive marine suboxia during the Great Oxidation Event

    NASA Astrophysics Data System (ADS)

    Kipp, Michael A.; Stüeken, Eva E.; Bekker, Andrey; Buick, Roger

    2017-01-01

    It has been proposed that an “oxygen overshoot” occurred during the early Paleoproterozoic Great Oxidation Event (GOE) in association with the extreme positive carbon isotopic excursion known as the Lomagundi Event. Moreover, it has also been suggested that environmental oxygen levels then crashed to very low levels during the subsequent extremely negative Shunga–Francevillian carbon isotopic anomaly. These redox fluctuations could have profoundly influenced the course of eukaryotic evolution, as eukaryotes have several metabolic processes that are obligately aerobic. Here we investigate the magnitude of these proposed oxygen perturbations using selenium (Se) geochemistry, which is sensitive to redox transitions across suboxic conditions. We find that δ82/78Se values in offshore shales show a positive excursion from 2.32 Ga until 2.1 Ga (mean +1.03 ± 0.67‰). Selenium abundances and Se/TOC (total organic carbon) ratios similarly show a peak during this interval. Together these data suggest that during the GOE there was pervasive suboxia in near-shore environments, allowing nonquantitative Se reduction to drive the residual Se oxyanions isotopically heavy. This implies O2 levels of >0.4 μM in these settings. Unlike in the late Neoproterozoic and Phanerozoic, when negative δ82/78Se values are observed in offshore environments, only a single formation, evidently the shallowest, shows evidence of negative δ82/78Se. This suggests that there was no upwelling of Se oxyanions from an oxic deep-ocean reservoir, which is consistent with previous estimates that the deep ocean remained anoxic throughout the GOE. The abrupt decline in δ82/78Se and Se/TOC values during the subsequent Shunga–Francevillian anomaly indicates a widespread decrease in surface oxygenation.

  18. Simulation of Record Rainfall Event Over Mumbai on 26 July, 2005

    NASA Astrophysics Data System (ADS)

    Singh, G. P.; Oh, Jai-Ho; Chaudhary, H. K.

    2010-05-01

    The Santa Cruz observatory at Mumbai airport recorded a very heavy precipitation of 94.4 cm (in less than 24 hours) on 26 July 2005. The country important commercial city came to a complete standstill due to severe flooding. This flooding situation caused a severe damage of life and poverty. The Financial Times and Economics Times news on 4 August 2005 have reported that the number of dead in the Maharashtra floods could well be above 1000 and around Rs. 5000 crores estimated loss in the state. We have simulated a case of extremely high precipitation using a National Centre for Atmospheric Research regional climate model (RegCM3) at 20 km horizontal resolution. Results indicate that the model captures well the well-marked cyclonic circulation (low) and the simulated precipitation is more close to observed value of precipitation when FC, KUO and AS convective cumulus parametrizations schemes are used.

  19. The first annually-resolved lake record of extreme precipitation events since AD 1374 in NE Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Corella, Juan Pablo; Benito, Gerardo; Rodríguez-Lloveras, Xavier; Brauer, Achim; Valero-Garcés, Blas L.

    2014-05-01

    Lake Montcortès is a small (0.14 km2 surface area), 30 m deep, karstic lake located in the eastern Pre-Pyrenees (NE Spain). The permanent anoxic hypolimnetic conditions in this lake have favored the preservation of finely annually laminated sediments in central-distal areas of the lake basin for the last three millennia. A robust age model has been established through varve counting on petrographic thin sections combined with radiocarbon and 210Pb dating. The good correlation of the varve counting with the 14C AMS dates underlines the annual nature of the lamination. Three main types of detrital microfacies have been distinguished in the varves: i) non-continuous detrital layers; ii) continuous detrital layers; iii) matrix-supported layers. In addition, two types of turbidite layers have been identified. Transport mechanisms have been proposed for those deposits including slope reworking processes as well as interflow and underflow events. Annual number of detrital layers interbedded within this varve record was compared against instrumental records of extreme daily rainfalls (available since 1917) providing minimum rainfall thresholds and return periods associated to the identified types of clastic microfacies. Non-continuous detrital layers are deposited during rainfall events higher than 80 mm (> 2 years in average recurrence interval) while graded detrital layers and turbidites were associated with even higher amplitude rainfall events (> 90mm and > 4 years recurrence interval). The frequency distribution of extreme hydro-meteorological events during the last centuries is not stationary and its pattern coincides with historical floods from the nearby Segre River. Higher heavy rainfall frequency occurred during AD 1347-1400 and AD 1844-1894, while less rainfall events happened at AD 1441-1508, 1547-1592, 1656-1712, 1765-1822 and 1917-2012. Variations in extreme rainfall frequencies prior to the 20th century show a positive correlation with solar activity

  20. Extraterrestrial Impact Event Recorded in the Late Triassic Deep-Sea Deposits from Japan

    NASA Astrophysics Data System (ADS)

    Sato, H.; Shirai, N.; Ebihara, M.; Nozaki, T.; Suzuki, K.; Onoue, T.; Kiyokawa, S.

    2014-12-01

    The Late Triassic is marked by the formation of several large impact structures on the Earth, including the 90-km-diameter Manicouagan crater in Canada (Spray and Kelly, 1998). Anomalously high platinum group element (PGE) concentrations have been reported from the Upper Triassic deep-sea deposits in Japan, which have been interpreted to be derived from an extraterrestrial impact event forming the Manicouagan crater (Onoue et al., 2012; Sato et al., 2013). However, previous studies have not clarified the composition of the projectile. Here we report the PGE element ratios and osmium (Os) isotopic compositions of the Upper Triassic ejecta layers in Japan in order to understand the projectile component. Evidence for the Late Triassic impact event has been discovered in the deep-sea claystone layers at four bedded chert sections in the Japanese accretionary complex. The claystone layers contain microspherules, Ni-rich magnetite grains and high abundance of PGEs (Onoue et al., 2012). Biostratigraphic analysis of radiolarian fossils from the studied sections revealed that the claystone layers occur embedded in the upper middle Norian (Sugiyama, 1997; Onoue et al., 2012). Identification of the projectile is attempted by comparing the isotope and elemental ratios of the ejecta deposit with similar data obtained from meteorites. The Ru/Ir and Pt/Ir ratios of all the claystone samples from the study sites are plotted along the mixing line between chondrites and upper continental crust. Although chondrites cannot be distinguished from iron meteorites by using PGE/Ir ratios, the claystone layers have Cr/Ir ratios between 104-105, indicating that the claystone layers are clearly contaminated by chondritic material. The Os isotope data show an abrupt and marked negative excursion from an initial Os isotope ratio of ~0.477 to unradiogenic values of ~0.126 in a claystone layer within a middle Norian bedded chert, indicating the input of chondrite-derived Os into seawater. The

  1. Utilizing precipitation chemistry records to investigate the role of dust concentrations in `Atmospheric River' events from west US coastal states

    NASA Astrophysics Data System (ADS)

    McCabe-Glynn, S. E.; Welker, J. M.; Sellars, S. L.; Johnson, K. R.

    2016-12-01

    Extreme precipitation events along the west coast of the US are commonly associated with atmospheric rivers (ARs), whereby extensive fluxes of moisture are transported outside the tropics and can result in major damage. Recent research has linked precipitation in the western US to airborne dust and other particles from the Sahara and Asian deserts. Increased amounts of dust can provide cloud condensation nuclei to form into cloud droplets and is expected to increase with a warming climate, thereby playing an important role in landfalling ARs. Currently, the CalWater 2015 campaign is measuring how aerosol particles interact with ARs, both offshore and when they reach the coast to determine how airborne dust affects the amount and type of precipitation that eventually falls. Results indicate a relationship between dust and biological aerosols detected in in situ cloud and precipitation residues. Understanding how dust concentration variations influence precipitation amounts can help to improve our knowledge of their influence on AR events. Many studies indicate that calcium (Ca2+) in polar ice cores is a good proxy of terrestrial dust. Additionally, a recent study in the southwestern US found rain and snow pH levels, usually between 5-6, exhibited their highest concentrations between March and June due mostly to dust, (crustal-derived species Ca2+, Mg2+, K+, and Na+) playing a major role in acid neutralization. Here we utilize United States Network for Isotopes in Precipitation (USNIP) and National Atmospheric Deposition Program (NADP) weekly precipitation amount and chemistry records from 1981 to 2015 to investigate the average ion concentration variations of Ca, Mg, K, Na, and the pH to determine if and how they changed during AR events. We analyze a North-South transect of sites across the US coastal states (WA, OR, and CA) which received extreme precipitation (>100 mm) and coincide with noted AR events. We also utilize PERSIANN-CONNECT, a global extreme

  2. Sulfur record of rising and falling marine oxygen and sulfate levels during the Lomagundi event

    PubMed Central

    Planavsky, Noah J.; Bekker, Andrey; Hofmann, Axel; Owens, Jeremy D.; Lyons, Timothy W.

    2012-01-01

    Carbonates from approximately 2.3–2.1 billion years ago show markedly positive δ13C values commonly reaching and sometimes exceeding +10‰. Traditional interpretation of these positive δ13C values favors greatly enhanced organic carbon burial on a global scale, although other researchers have invoked widespread methanogenesis within the sediments. To resolve between these competing models and, more generally, among the mechanisms behind Earth’s most dramatic carbon isotope event, we obtained coupled stable isotope data for carbonate carbon and carbonate-associated sulfate (CAS). CAS from the Lomagundi interval shows a narrow range of δ34S values and concentrations much like those of Phanerozoic and modern marine carbonate rocks. The δ34S values are a close match to those of coeval sulfate evaporites and likely reflect seawater composition. These observations are inconsistent with the idea of diagenetic carbonate formation in the methanic zone. Toward the end of the carbon isotope excursion there is an increase in the δ34S values of CAS. We propose that these trends in C and S isotope values track the isotopic evolution of seawater sulfate and reflect an increase in pyrite burial and a crash in the marine sulfate reservoir during ocean deoxygenation in the waning stages of the positive carbon isotope excursion. PMID:23090989

  3. Sulfur record of rising and falling marine oxygen and sulfate levels during the Lomagundi event.

    PubMed

    Planavsky, Noah J; Bekker, Andrey; Hofmann, Axel; Owens, Jeremy D; Lyons, Timothy W

    2012-11-06

    Carbonates from approximately 2.3-2.1 billion years ago show markedly positive δ(13)C values commonly reaching and sometimes exceeding +10‰. Traditional interpretation of these positive δ(13)C values favors greatly enhanced organic carbon burial on a global scale, although other researchers have invoked widespread methanogenesis within the sediments. To resolve between these competing models and, more generally, among the mechanisms behind Earth's most dramatic carbon isotope event, we obtained coupled stable isotope data for carbonate carbon and carbonate-associated sulfate (CAS). CAS from the Lomagundi interval shows a narrow range of δ(34)S values and concentrations much like those of Phanerozoic and modern marine carbonate rocks. The δ(34)S values are a close match to those of coeval sulfate evaporites and likely reflect seawater composition. These observations are inconsistent with the idea of diagenetic carbonate formation in the methanic zone. Toward the end of the carbon isotope excursion there is an increase in the δ(34)S values of CAS. We propose that these trends in C and S isotope values track the isotopic evolution of seawater sulfate and reflect an increase in pyrite burial and a crash in the marine sulfate reservoir during ocean deoxygenation in the waning stages of the positive carbon isotope excursion.

  4. Late Miocene events in the Mediterranean as recorded by carbonate-evaporite relations

    SciTech Connect

    Rouchy, J.M. ); Martin, J.P.S. )

    1992-07-01

    The Messinian Stage in the Mediterranean region is known mainly because of a major evaporitic event whose causes and global implications are still under discussion. Correlations between basinal evaporite-bearing series and marginal carbonate platforms allow for improvement of the classical depostional models, especially concerning the eustatic control of the environmental changes in the Mediterranean. These changes were controlled by the interplay of aperiodic and periodic factors: (1) tectonics, related to the relative motions of the African and Eurasian plates and resultant linear increase in the basin restriction; (2) sea-level fluctuations that alternately aggravated the restriction or allowed marine replenishment, and (3) climatic fluctuations that controlled the level of the Mediterranean during stages of isolation. The Messinian sedimentary succession reflects a typical sequence of progressive isolation: marine marls {yields} laminites {yields} transitional deposits {yields} evaporites {yields} lacustrine deposits. The first stage of the so-called 'salinity crisis' was characterized by a Mediterranean lowstand that resulted in erosion of former platforms and deposition of the lower evaporites. During the next stage, sea level rose (TB3.3 cycle) high enough to temporarily replenish the basin (cyclic upper evaporites, with development of stromatolite-rich deposits). Finally, the uppermost Messinian freshwater to brackish lacustrine deposits reflect both the cessation of sea-water input (maximum tectonic isolation, low sea level) and freshwater input related to increasing runoff.

  5. Past flood events reflected in Holocene floodplain records of East-Germany

    NASA Astrophysics Data System (ADS)

    Schneider, H.; Höfer, D.; Mäusbacher, R.; Gude, M.

    2007-12-01

    The sediment archives in lakes and mires formed by salt solution within the floodplain of the Middle Werra river were used to detect effects of climate and landuse changes on the sedimentation regime of the river by means of high-resolution sedimentological and palynological methods. All archives of the Middle Werra valley show similar sedimentation sequences which are mainly influenced by climate until the Middle Ages and mostly affected by human activity between the Middle Ages and Modern Times. The likelihood of climatic influences in terms of wetter conditions is especially given by a clear increase of indicators for floodplain forest, reed communities and aquatics in combination with decreasing human landuse indicators in the investigation area. In addition, the palynological results show that the sediment input in these depressions is higher both during periods with wetter conditions and with increased human impact in the catchment. According to the fact, that during flood events the river is hydrological connected with these depressions, the minerogenic layers are suspected to be delivered during floods.

  6. To what extent are adverse events found in patient records reported by patients and healthcare professionals via complaints, claims and incident reports?

    PubMed

    Christiaans-Dingelhoff, Ingrid; Smits, Marleen; Zwaan, Laura; Lubberding, Sanne; van der Wal, Gerrit; Wagner, Cordula

    2011-02-28

    Patient record review is believed to be the most useful method for estimating the rate of adverse events among hospitalised patients. However, the method has some practical and financial disadvantages. Some of these disadvantages might be overcome by using existing reporting systems in which patient safety issues are already reported, such as incidents reported by healthcare professionals and complaints and medico-legal claims filled by patients or their relatives. The aim of the study is to examine to what extent the hospital reporting systems cover the adverse events identified by patient record review. We conducted a retrospective study using a database from a record review study of 5375 patient records in 14 hospitals in the Netherlands. Trained nurses and physicians using a method based on the protocol of The Harvard Medical Practice Study previously reviewed the records. Four reporting systems were linked with the database of reviewed records: 1) informal and 2) formal complaints by patients/relatives, 3) medico-legal claims by patients/relatives and 4) incident reports by healthcare professionals. For each adverse event identified in patient records the equivalent was sought in these reporting systems by comparing dates and descriptions of the events. The study focussed on the number of adverse event matches, overlap of adverse events detected by different sources, preventability and severity of consequences of reported and non-reported events and sensitivity and specificity of reports. In the sample of 5375 patient records, 498 adverse events were identified. Only 18 of the 498 (3.6%) adverse events identified by record review were found in one or more of the four reporting systems. There was some overlap: one adverse event had an equivalent in both a complaint and incident report and in three cases a patient/relative used two or three systems to complain about an adverse event. Healthcare professionals reported relatively more preventable adverse events

  7. Climatic, volcanic and tectonic events recorded in recent sediments of the Rukwa rift, Western Tanzania

    NASA Astrophysics Data System (ADS)

    Delvaux, D.; Mees, F.; Williamson, D.; Macheyeki, A. S.

    2009-04-01

    Lake Rukwa is now a shallow lake occupying the floor of the closed Rukwa depression in the western branch of the East African Rift System. Sediment records of the paleo-lake level show that during the Late Pleistocene to Early Holocene, Lake Rukwa reached the level of the overflow sill, 180 m higher than its present level, and was overflowing into Lake Tanganyika. Lacustrine sediments from this period are now exposed on the margin of the depression, and in particular along the Songwe River, where several large sections up to 35 meters high can be studied. Investigation of selected sections reveals a complex evolution in alternating fluvio-deltaic to lacustrine environment, punctuated by episodic inflow of volcanic material from the nearby Rungwe Volcanic Province. Macroscopic description of the sedimentary packages and their geometry, combined with C14 dating, diatom analysis, and optical microscopy allow to propose a preliminary evolution scheme in which climatically induced lake level change, volcanic input and tectonic influence can be reconstructed. In particular, correlations between sections at different altitudes allow to better constrain the lake level fluctuation than previous estimates based on drill core analysis.

  8. Basaltic impact melts in the Apollo collections: How many impacts and which events are recorded?

    NASA Technical Reports Server (NTRS)

    Spudis, Paul D.

    1992-01-01

    Many of the rocks in the Apollo collections from the lunar highlands are impact melt breccias of basaltic bulk composition. They are known by a variety of names including low-K Fra Mauro basalt, VHA basalt, and basaltic impact melts. These rocks have been studied to understand the compositional nature of the lunar crust, to decipher the processes of large body impact, and to comprehend the record of impact bombardment of the Moon. Study of terrestrial craters has led to a model for impact melt generation whereby target lithologies are totally melted during impact. The impact melt makes up a few percent of the total volume of crater material; superheated silicate liquids of the impact melt have extremely low viscosities and mix intimately. This mixing thoroughly homogenizes the melt chemically during the excavation of the crater. Colder, unmelted debris is overridden by the melt sheet as the crater cavity grows. Incorporation of these cold clasts rapidly chills the melt, with zones of greater and lesser amounts of clasts being primarily responsible for modestly differing thermal regimes. The net effect of this process is the production of a suite of rocks that have extreme chemical homogeneity, but wide petrographic diversity. Strict application of this model to the petrogenesis of basaltic impact melts from the Moon has some fairly significant consequences for how we interpret early lunar history. The consequences are briefly discussed.

  9. A Multiproxy Record of the Toarcian Oceanic Anoxic Event in Shallow-Water Carbonates from the Dinaric Carbonate Platform, Slovenia

    NASA Astrophysics Data System (ADS)

    Ettinger, N. P.; Martindale, R. C.; Kosir, A.; Thibodeau, A. M.

    2016-12-01

    Oceanic anoxic events (OAEs) have been shown to have an intimate influence on source rock deposition, marine extinctions, and the reorganization of carbonate factories throughout geologic time. Today, the possibility of environmental deterioration such as warming, acidification, and decreased oxygenation in modern oceans has increased the importance of ancient analogues. Therefore, studies of ancient rapid environmental change, such as the Toarcian Oceanic Anoxic Event, can inform our understanding of how marine ecosystems will respond to similar stresses in the future. The Toarcian OAE coincides with a marine mass extinction and the deposition of deep-water black shales; the putative cause of the OAE is the emplacement of the Karoo-Ferrar-Chon Aike Large Igneous Province. Although black shales are the hallmark of oceanic anoxic events, the contemporaneous shallow marine response to anoxia and other stresses is subtler and poorly documented by comparison. We will present a record of Pliensbachian-Toarcian aged shallow-water carbonates from the Dinaric Carbonate Platform in Slovenia. This platform provides a key record of the Toarcian OAE, as it is one of the few platforms from the Tethys Ocean that experienced nearly continuous sedimentation throughout the Pliensbachian and Toarcian as a result of tectonic quiescence. Sedimentological, geochemical, and paleontological data from two sections of the Trnovski Gozd karst plateau are used to assess the timing of volcanism and the response of biotic and abiotic carbonates to environmental changes associated with the OAE. Benthic forams, dasycladacean algae, and oncolitic packstones dominate diverse skeletal assemblages in the Pliensbachian record. The stage boundary coincides with anomalies in redox-sensitive elements, a hiatus in carbonate production represented by marine firmgrounds, and an anomalous increase in mercury content. The early Toarcian record is dominated by crinoidal-oolitic packstones and grainstones

  10. Flash flood events recorded by air temperature changes in caves: A case study in Covadura Cave (SE Spain)

    NASA Astrophysics Data System (ADS)

    Gázquez, Fernando; Calaforra, José María; Fernández-Cortés, Ángel

    2016-10-01

    On 28th September 2012, more than 150 mm rain fell in just two hours in some points of southeastern Spain, triggering intense flash floods that resulted in the death of ten people and widespread material damage. In the gypsum karst of Sorbas, rainfall intensity reached 33 mm/h. Air temperature monitoring in different levels of Covadura Cave, down to 85 m depth, enabled the effect of this extreme episode on the cave microclimate to be evaluated in real time. The cave air temperature increased by between 0.9 and 4.1 °C as a result of water flow into the cavity and intense mixing of air masses, in addition to the displacement of deeper air masses toward shallower levels produced by fast recharge of the surrounding karst aquifer. The lag between peak rainfall intensity and the highest cave air temperature was 5-6 h, indicating the response time of the karst to this rainfall event. No trends with depth were observed, suggesting that water not only flowed in through the main cave entrance but also through secondary accesses and fractures. Furthermore, the size of the cave passages and the intensity of air turbulence generated by waterfalls in the cave played an important role in producing these temperature differences. Even though the rainfall event lasted 10 h, cave air temperature did not return to pre-flash flood values until more than 20 days later. This indicates that, while waterflow through the cave might stop a few hours after the rainfall event, cave air temperature can be affected over a longer period. This can be explained by slow groundwater level decreasing of the surrounding karst aquifer and latent heat liberation produced by moisture condensation on the cave walls. Our results show how continuous monitoring of air temperature in caves can be a useful tool for evaluating the short-term effects of flash floods in subterranean karst systems.

  11. Glacial freshwater discharge events recorded by authigenic neodymium isotopes in sediments from the Mendeleev Ridge, western Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Jang, Kwangchul; Han, Yeongcheol; Huh, Youngsook; Nam, Seung-Il; Stein, Ruediger; Mackensen, Andreas; Matthiessen, Jens

    2013-05-01

    The freshwater budget of the Arctic Ocean is a key component governing the deep water formation in the North Atlantic and the global climate system. We analyzed the isotopic composition of neodymium (ɛNd) in authigenic phases of marine sediments on the Mendeleev Ridge in the western Arctic Ocean spanning an estimated time interval from present to about 75 ka BP. This continuous record was used to reconstruct the ɛNd of the polar deep water (PDW) and changes in freshwater sources to the PDW through time. Three deviations in ɛNd from a long term average of -10.2 were identified at estimated 46-51, 35-39 and 13-21 ka BP. The estimated 46-51 ka BP event can be traced to bursting of ice-dammed lakes accompanying the collapse of the Barents-Kara Ice Sheet, which would have released radiogenic Nd to the eastern Arctic Ocean. The cyclonic surface circulation in the eastern Arctic Ocean must have been stronger than at present for the event to be recorded on the Mendeleev Ridge. For the 35-39 and 13-21 ka BP events, it is likely that the Laurentide Ice Sheet (LIS) supplied the unradiogenic freshwater. The configuration of the anticyclonic circulation in the western Arctic was probably similar to today or expanded eastward. Our simple mass balance calculations suggest that large amounts of freshwater were released but due to significant deep water formation within the Arctic Ocean, the effect on the formation of NADW was probably minor.

  12. Common data elements for secondary use of electronic health record data for clinical trial execution and serious adverse event reporting.

    PubMed

    Bruland, Philipp; McGilchrist, Mark; Zapletal, Eric; Acosta, Dionisio; Proeve, Johann; Askin, Scott; Ganslandt, Thomas; Doods, Justin; Dugas, Martin

    2016-11-22

    Data capture is one of the most expensive phases during the conduct of a clinical trial and the increasing use of electronic health records (EHR) offers significant savings to clinical research. To facilitate these secondary uses of routinely collected patient data, it is beneficial to know what data elements are captured in clinical trials. Therefore our aim here is to determine the most commonly used data elements in clinical trials and their availability in hospital EHR systems. Case report forms for 23 clinical trials in differing disease areas were analyzed. Through an iterative and consensus-based process of medical informatics professionals from academia and trial experts from the European pharmaceutical industry, data elements were compiled for all disease areas and with special focus on the reporting of adverse events. Afterwards, data elements were identified and statistics acquired from hospital sites providing data to the EHR4CR project. The analysis identified 133 unique data elements. Fifty elements were congruent with a published data inventory for patient recruitment and 83 new elements were identified for clinical trial execution, including adverse event reporting. Demographic and laboratory elements lead the list of available elements in hospitals EHR systems. For the reporting of serious adverse events only very few elements could be identified in the patient records. Common data elements in clinical trials have been identified and their availability in hospital systems elucidated. Several elements, often those related to reimbursement, are frequently available whereas more specialized elements are ranked at the bottom of the data inventory list. Hospitals that want to obtain the benefits of reusing data for research from their EHR are now able to prioritize their efforts based on this common data element list.

  13. Varved sediment records in Scotland: towards improving the chronology of events during the Last Glacial-Interglacial Transition

    NASA Astrophysics Data System (ADS)

    MacLeod, Alison; Palmer, Adrian; Lowe, John; Rose, Jim; Bryant, Charlotte

    2010-05-01

    This paper focuses on investigating the timing, rates and duration of key shifts in climate during the Late Quaternary in Scotland. The Greenland Ice Core records have demonstrated how rapidly climate shifts can take place. How rapidly they are propagated, however, and how they are expressed in marine and terrestrial records at hemispheric or global scales is still contended. Many traditional chronological tools applied in these latter contexts, i.e. radiocarbon; do not currently provide the accuracy or the precision required to precisely constrain the timing of the onset and end of short-lived, high-magnitude events such as the Younger Dryas. Results are presented from two former glaciolacustrine basins in Scotland which preserve annually laminated sediments. These indicate that Glacial Lake Blane, in the south of the Loch Lomond Readvance (LLR) ice cap, existed for a minimum of 259 ±3 years directly following deposition of an organic layer dated to between 12,117 and 11,650 cal yrs BP. Loch Laggan East, in the north of the LLR ice cap existed for 509 ±4 years, its onset dated to between approximately 12,300 and 12,090 cal yrs BP. The absolute age of the two varve series are constrained by discrete tephra horizons and multiple radiocarbon determinations, which are combined within Bayesian statistical frameworks. These are integrated with other robust stratigraphic and chronological information and provide the most precise age estimates yet attained for the timing and duration of key events in Scotland during the Loch Lomond Stadial. They suggest that ice arrived at its maximal position later than previously supposed and may have lingered in parts of the Scottish Highlands into the Early Holocene. This research begins to pave the way for comparing events occurring in Scotland during the Lateglacial period with those elsewhere in the North Atlantic region, with sub-centennial precision.

  14. Late Quaternary climatic events and sea-level changes recorded by turbidite activity, Dakar Canyon, NW Africa

    NASA Astrophysics Data System (ADS)

    Pierau, Roberto; Hanebuth, Till J. J.; Krastel, Sebastian; Henrich, Rüdiger

    2010-03-01

    The relationship of sea-level changes and short-term climatic changes with turbidite deposition is poorly documented, although the mechanisms of gravity-driven sediment transport in submarine canyons during sea-level changes have been reported from many regions. This study focuses on the activity of the Dakar Canyon off southern Senegal in response to major glacial/interglacial sea-level shifts and variability in the NW-African continental climate. The sedimentary record from the canyon allows us to determine the timing of turbidite events and, on the basis of XRF-scanning element data, we have identified the climate signal at a sub-millennial time scale from the surrounding hemipelagic sediments. Over the late Quaternary the highest frequency in turbidite activity in the Dakar Canyon is confined to major climatic terminations when remobilisation of sediments from the shelf was triggered by the eustatic sea-level rise. However, episodic turbidite events coincide with the timing of Heinrich events in the North Atlantic. During these times continental climate has changed rapidly, with evidence for higher dust supply over NW Africa which has fed turbidity currents. Increased aridity and enhanced wind strength in the southern Saharan-Sahelian zone may have provided a source for this dust.

  15. Immune globulins and thrombotic adverse events as recorded in a large administrative database in 2008 through 2010.

    PubMed

    Daniel, Gregory W; Menis, Mikhail; Sridhar, Gayathri; Scott, Dorothy; Wallace, Anna E; Ovanesov, Mikhail V; Golding, Basil; Anderson, Steven A; Epstein, Jay; Martin, David; Ball, Robert; Izurieta, Hector S

    2012-10-01

    Thrombotic events (TEs) are rare but often serious adverse events that could occur after administration of immune globulin (IG) products. Our study objective was to assess occurrence of recorded TEs after administration of different US-licensed IG products and investigate potential risk factors using a large administrative database. This is a retrospective claims-based cohort study of individuals exposed to IG products from January 1, 2008, through September 30, 2010, using HealthCore's Integrated Research Database, a longitudinal health care database. IG products were identified by recorded Healthcare Common Procedure Coding System codes. TEs were ascertained via International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for same-day TEs by IG product, while controlling for confounders. Of 11,785 individuals exposed to IG products in the study period, 122 (1%) had TE(s) recorded on the same day as IG administration. TE rates per 1000 persons exposed ranged from 6.1 to 20.5 for different IG product groups. Vivaglobin users had an increased same-day TE risk compared to reference Gammagard Liquid users (OR, 3.56; 95% CI, 1.54-8.23). An increased TE risk was also found with older age (≥ 45 years), prior TE(s), and hypercoagulable state(s). The study suggests potentially elevated TE rates for different IG products, including subcutaneous. It also identifies important recipient TE risk factors and suggests that risk-benefit profiles should be weighed before IG administration. The observed differences may be due to various factors such as dosage, administration rates, and product manufacturing processes that warrant further evaluation. © 2012 American Association of Blood Banks.

  16. Is a 50 Ma Event Recorded in the Absolute Plate Motion of Africa?

    NASA Astrophysics Data System (ADS)

    Maher, S. M.; Wessel, P.; Müller, R.; Harada, Y.

    2012-12-01

    There is considerable evidence for a global plate tectonic reorganization at ~Chron 21, as suggested by observed changes in global relative plate motion (RPM). The timings of these events appear to coincide with the age of the Hawaiian Emperor Bend (HEB), i.e., ~47-50 Ma. This 120° bend has traditionally been the poster child for the fixed hotspot hypothesis, suggesting the Pacific plate underwent a change in absolute plate motion (APM) as it moved over a more or less stationary Hawaiian hotspot. However, palaeomagnetic evidence favors southward motion of the Hawaii hotspot during the Emperor stage, limiting the amount of APM change required. In the Indo-Atlantic realm, RPMs involving Africa all seem compatible with a change in Africa APM around ~50 Ma. If this global plate reorganization took place there should also be physical evidence on the Africa plate itself due to the change in Africa APM. A candidate for such evidence may be the Réunion-Mascarene bend, which exhibits many HEB-like features. However, the Réunion hotspot also created the Chagos-Laccadive ridge as it encountered (and later crossed) the Carlsberg Ridge, and the oldest Mascarene section closest to the Seychelles may be continental in origin; thus there is some uncertainty in how to interpret the geometry. Furthermore, published APM models have had difficulty modeling this abrupt change in orientation. To reexamine this problem we derived a new Africa APM model that goes back to ~65 Ma using the Hybrid Polygonal Finite Rotation Method. The modeling incorporates the geometry and ages of seamount chains on the Africa plate and their associated hotspots as suitable constraints on an Africa APM model. The present as well as earlier positions of hotspots can be adjusted to get the best fit for the model. We examine how models with or without a ~50 Ma bend satisfy the geometries and age progressions of hotspot chains on the Africa plate and how well the predictions match observed paleolatitudes.

  17. Record of seismotectonic events in siliceous cyanobacterial sediments (Magadi cherts), Lake Magadi, Kenya

    NASA Astrophysics Data System (ADS)

    Behr, H.-J.; Röhricht, C.

    The Quaternary sediments of Lake Magadi in the Kenya Rift include large volumes of chert. Before their lithification, these siliceous sediments underwent very strong deformation, as recorded by diapirism with pillow-chert mounds, extrusion along dykes and fault ramps, horizontal liquefaction slides with brecciation, slumping, as well as petee-, flow- and shear structures. Eugster (1969) considered these structures to have resulted from desiccation of Na-silicate precipitates (magadiite) that were deposited over wide areas and were several metres thick. Magadiite can remain soft over long periods; therefore, these ``Magadi-type cherts'' are called the type examples of inorganic cherts. However, field observations and microbiological studies of the cherts show that real inorganic cherts are rare at the type locality of Magadi-type cherts. Most of the cherts are older than the High Magadi Beds and developed from flat-topped calcareous bioherms of Pleurocapsa, Gloecocapsa, and other coccoid cyanobacteria, thinly bedded filamentous microbial mats, stromatolites, bacterial slimes, diatoms, Dascladiacea colonies and other organic matter. Silicification occurred from a silicasol via opal-A to opal-C with final recrystallisation to a chert of quartzine composition. The metabolic processes of cyanobacteria controlled the pH and influenced the dissolution-precipitation mechanism. Collapse, liquefaction and extrusion of the pre-lithified siliceous matrix was caused by seismotectonic rift activity, which activated fault scarplets and large-scale dyke systems. It led to liquefaction and other earthquake-induced structures along the fault ramps and on tilted blocks. Concentrated silicasols were generated by the interaction of alkaline waters with volcanic detritus, coupled with biochemical processes. After liquefaction and extrusion, the material solidified by spontaneous crystallisation in an environment that was characterised by highly variable pH and salinity. The Lake Magadi

  18. Internal waves, an under-explored source of turbulence events in the sedimentary record

    NASA Astrophysics Data System (ADS)

    Pomar, L.; Morsilli, M.; Hallock, P.; Bádenas, B.

    2012-02-01

    Internal waves occur nearly ubiquitously in lakes and oceans yet their sedimentary records remain largely unrecognized. Waves propagate at the interface between fluids of different densities. Surface waves propagate at the interface between air and water, which is a strong density gradient. Internal waves propagate along weaker gradients (pycnoclines) within density-stratified fluids, behaving similarly to surface waves but typically at lower frequencies and larger amplitudes. Internal waves that occur at tidal frequencies are called internal tides; they are very common on the outer continental shelf and slope, and are generated as the surface tides move stratified water up and down a sloping surface. Large internal solitary waves known as solitons are ubiquitous wherever strong currents and stratification occur in the vicinity of irregular topography. These waves can force short-period, strong bottom-current pulses and may trigger upslope-surging vortex cores of dense fluid (boluses) that can induce mobilization of bottom sediments. Internal-wave deposits (internalites) are highly variable and definitive criteria for recognition are still to be developed. In terrigenous-clastic systems and shallow-water settings, internalites can be seen as "out-of-context" tempestites, detached from shore-related deposits and lacking thickening/coarsening upward sequences. In contrast to surface storm waves, the impact of internal waves is usually strongest in mid-outer-shelf regions and weaker in shallow water. Internal waves also provide a plausible mechanism to explain the origin of hummocky cross-stratification, especially their occurrence in different depositional environments. In deeper settings (continental slopes and canyons), internalites may have sedimentary structures indicating tidal currents and may coexist with turbidites. In carbonate systems, internal waves influence both sediment remobilization and the carbonate-producing biota. Differentiation between internal

  19. Classification and evaluation of the documentary-recorded storm events in the Annals of the Choson Dynasty (1392-1910), Korea

    NASA Astrophysics Data System (ADS)

    Yoo, Chulsang; Park, Minkyu; Kim, Hyeon Jun; Choi, Juhee; Sin, Jiye; Jun, Changhyun

    2015-01-01

    In this study, the analysis of documentary records on the storm events in the Annals of the Choson Dynasty, covering the entire period of 519 years from 1392 to 1910, was carried out. By applying various key words related to storm events, a total of 556 documentary records could be identified. The main objective of this study was to develop rules of classification for the documentary records on the storm events in the Annals of the Choson Dynasty. The results were also compared with the rainfall data of the traditional Korean rain gauge, named Chukwooki, which are available from 1777 to 1910 (about 130 years). The analysis is organized as follows. First, the frequency of the documents, their length, comments about the size of the inundated area, the number of casualties, the number of property losses, and the size of the countermeasures, etc. were considered to determine the magnitude of the events. To this end, rules of classification of the storm events are developed. Cases in which the word 'disaster' was used along with detailed information about the casualties and property damages, were classified as high-level storm events. The high-level storm events were additionally sub-categorized into catastrophic, extreme, and severe events. Second, by applying the developed rules of classification, a total of 326 events were identified as high-level storm events during the 519 years of the Choson Dynasty. Among these high-level storm events, only 19 events were then classified as the catastrophic ones, 106 events as the extreme ones, and 201 events as the severe ones. The mean return period of these storm events was found to be about 30 years for the catastrophic events, 5 years for the extreme events, and 2-3 years for the severe events. Third, the classification results were verified considering the records of the traditional Korean rain gauge; it was found that the catastrophic events are strongly distinguished from other events with a mean total rainfall and a

  20. Geochemical and palynological records for the end-Triassic Mass-Extinction Event in the NE Paris Basin (Luxemburg)

    NASA Astrophysics Data System (ADS)

    Kuhlmann, Natascha; van de Schootbrugge, Bas; Thein, Jean; Fiebig, Jens; Franz, Sven-Oliver; Hanzo, Micheline; Colbach, Robert; Faber, Alain

    2016-04-01

    The End-Triassic mass-extinction event is one of the "big five" mass extinctions in Earth's history. Large scale flood basalt volcanism associated with the break-up of Pangaea, which resulted in the opening of the central Atlantic Ocean, is considered as the leading cause. In addition, an asteroid impact in Rochechouart (France; 201 ± 2 Ma) may have had a local influence on ecosystems and sedimentary settings. The Luxembourg Embayment, in the NE Paris Basin, offers a rare chance to study both effects in a range of settings from deltaic to lagoonal. A multidisciplinary study (sedimentology, geochemistry, palynology) has been carried out on a number of outcrops and cores that span from the Norian to lower Hettangian. Combined geochemical and palynological records from the Boust core drilled in the NE Paris Basin, provide evidence for paleoenvironmental changes associated with the end-Triassic mass-extinction event. The Triassic-Jurassic stratigraphy of the Boust core is well constrained by palynomorphs showing the disappaerance of typical Triassic pollen taxa (e.g. Ricciisporites tuberculates) and the occurrence of the marker species Polypodiisporites polymicroforatus within the uppermost Rhaetian, prior to the Hettangian dominance of Classopollis pollen. The organic carbon stable isotope record (δ13Corg) spanning the Norian to Hettangian, shows a series of prominent negative excursions within the middle Rhaetian, followed by a trend towards more positive values (approx -24 per mille) within the uppermost Rhaetian Argiles de Levallois Member. The lowermost Hettangian is characterized by a major negative excursion, reaching - 30 per mille that occurs in organic-rich sediments. This so-called "main negative excursion" is well-known from other locations, for example from Mariental in Northern Germany and from St Audrie's Bay in England, and Stenlille in Denmark. Based on redox-sensitive trace element records (V, Cr, Ni, Co, Th, U) the lowermost Hettangian in most of

  1. A prospective study of low fasting glucose with cardiovascular disease events and all-cause mortality: The Women's Health Initiative.

    PubMed

    Mongraw-Chaffin, Morgana; LaCroix, Andrea Z; Sears, Dorothy D; Garcia, Lorena; Phillips, Lawrence S; Salmoirago-Blotcher, Elena; Zaslavsky, Oleg; Anderson, Cheryl A M

    2017-05-01

    While there is increasing recognition of the risks associated with hypoglycemia in patients with diabetes, few studies have investigated incident cause-specific cardiovascular outcomes with regard to low fasting glucose in the general population. We hypothesized that low fasting glucose would be associated with cardiovascular disease risk and all-cause mortality in postmenopausal women. To test our hypothesis, we used both continuous incidence rates and Cox proportional hazards models in 17,287 participants from the Women's Health Initiative with fasting glucose measured at baseline. Participants were separated into groups based on fasting glucose level: low (<80mg/dL), normal/reference (80-99mg/dL), impaired (100-125mg/dL), and diabetic (≥126mg/dL). Participants were free of cardiovascular disease at enrollment, had mean age of 62years, and were 52% Caucasian, 24% African American, 8% Asian, and 12% Hispanic. Median follow-up was 15years. Graphs of continuous incidence rates compared to fasting glucose distribution exhibited evidence of a weak J-shaped association with heart failure and mortality that was predominantly due to participants with treated diabetes. Impaired and diabetic fasting glucose were positively associated with all outcomes. Associations for low fasting glucose differed, with coronary heart disease (HR=0.64 (0.42, 0.98)) significantly inverse; stroke (0.73 (0.48, 1.13)), combined cardiovascular disease (0.91 (0.73, 1.14)), and all-cause mortality (0.97 (0.79, 1.20)) null or inverse and not significant; and heart failure (1.27 (0.80, 2.02)) positive and not significant. Fasting glucose at the upper range, but not the lower range, was significantly associated with incident cardiovascular disease and all-cause mortality. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Differing Event-Related Patterns of Gamma-Band Power in Brain Waves of Fast- and Slow-Reacting Subjects

    DTIC Science & Technology

    1994-05-01

    Wilhelm Wundt proposed that there are two types of subjects in sim- ple RT experiments: fast-reacting subjects, who respond before they fully...quickly as possible to auditory stimuli. This result appears to confirm long-standing speculations of Wundt that fast- and slow-reacting subjects...accord with the hypothesis of Wundt and others that slower ("sensorial") responders wait to fully perceive a stimulus and then react to their perception

  3. Methodology for using advanced event data recorders to reconstruct vehicle trajectories for use in safety impact methodologies (SIM).

    PubMed

    Kusano, Kristofer D; Sherony, Rini; Gabler, Hampton C

    2013-01-01

    Safety impact methodologies (SIMs) have the goal of estimating safety benefits for proposed active safety systems. Because the precrash movements of vehicles involved in real-world crashes are often unknown, previous SIMs have taken the approach to reconstruct collisions from incomplete information sources, such as scaled scene diagrams and photographic evidence. The objective of this study is to introduce a novel methodology for reconstructing the precrash vehicle trajectories using data from advanced event data recorders (EDRs). Some EDRs from model year 2009 and newer Ford vehicles can record steering wheel angle in addition to precrash vehicle speed, accelerator pedal, and throttle input prior to the crash. A model was constructed using these precrash records and a vehicle model developed in the simulation software PreScan. The model was validated using the yaw rate and longitudinal and lateral accelerations also recorded by this type of Ford EDR but not used to develop the models. In general, the model was able to approximate the dynamics recorded on the EDR. The model did not match the observed dynamics when either the vehicle departed the paved surface or when electronic stability control was active. Modifying the surface friction at the estimated point at which the vehicle departed the road produced better simulation results. The developed trajectories were used to simulate 2 road departure crashes, one into a fixed object and one into a vehicle traveling in the opposite direction, as if the departing vehicle were equipped with a lane departure warning (LDW) system. This example application demonstrates the utility of this method and its potential application to a SIM. This study demonstrated a novel method for crash reconstruction that can be applied to a SIM for active safety systems. Benefits of this method are that the driver inputs do not need to be inferred from other reconstructions because they are recorded directly by the EDR. Currently, there are

  4. What can we learn about the dynamics of DO-events from studying the high resolution ice core records?

    NASA Astrophysics Data System (ADS)

    Ditlevsen, Peter

    2017-04-01

    The causes for and possible predictions of rapid climate changes are poorly understood. The most pronounced changes observed, beside the glacial terminations, are the Dansgaard-Oeschger events. Present day general circulation climate models simulating glacial conditions are not capable of reproducing these rapid shifts. It is thus not known if they are due to bifurcations in the structural stability of the climate or if they are induced by stochastic fluctuations. By analyzing a high resolution ice core record we exclude the bifurcation scenario, which strongly suggests that they are noise induced and thus have very limited predictability. Ref: Peter Ditlevsen, "Tipping points in the climate system", in Nonlinear and Stochastic Climate Dynamics, Cambridge University Press (C. Franzke and T. O'Kane, eds.) (2016) P. D. Ditlevsen and S. Johnsen, "Tipping points: Early warning and wishful thinking", Geophys. Res. Lett., 37, L19703, 2010

  5. Immune globulins and same-day thrombotic events as recorded in a large health care database during 2008 to 2012.

    PubMed

    Sridhar, Gayathri; Ekezue, Bola F; Izurieta, Hector S; Selvam, Nandini; Ovanesov, Mikhail V; Divan, Hozefa A; Liang, Yideng; Golding, Basil; Forshee, Richard A; Anderson, Steven A; Menis, Mikhail

    2014-10-01

    Thrombotic events (TEs) are rare and serious adverse events after administration of immune globulin (IG) products. Our study evaluated the occurrence of same-day TEs for different IG products and ascertained potential risk factors. This retrospective cohort study utilized HealthCore's Integrated Research Database (HIRD) to assess individuals exposed to IGs during 2008 to 2012. IG products were identified using recorded procedure codes and TEs were ascertained using ICD-9-CM diagnosis codes. The unadjusted same-day TE rates (per 1000 persons exposed) were estimated overall and by IG products, age, and sex. Multivariable logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for same-day TEs by IG products. Of 14,944 individuals exposed to IG products, 233 (15.6 per 1000 persons) had TE diagnosis code(s) recorded on the same-day as the IG exposure. Compared to Gammagard Liquid, Gammaplex (OR, 20.96; 95% CI, 2.45-179.33) and Vivaglobin (OR, 2.74; 95% CI, 1.19-6.32) users had a significantly increased same-day TE risk. Elevated, but nonsignificant TE risks were identified for Octagam, Gamunex, Privigen, and Lyophilized IG(s). An increased TE risk was also found with older age (≥45 years), prior TEs, and other health conditions. Our claims-based cohort study suggests a potentially elevated TE risk with different IG products and shows importance of recipient factors such as older age, previous TE, hypercoagulable state(s), and other health conditions. The results of this study suggest the need for continuous evaluation of procoagulant activity and manufacturing processes for IG products to further assure their safety. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  6. Stable Hydrogen Isotopes of Terrestrial n-alkanes record the Mid Younger Dryas Event in European Lakes

    NASA Astrophysics Data System (ADS)

    Muegler, I.; Gleixner, G.; Sachse, D.; Grafenstein, U. V.

    2007-12-01

    Compound-specific hydrogen isotope measurements (expressed as δD values) on lacustrine long- chained n-alkanes are a potentially promising means of reconstructing variations in the isotopic composition of continental precipitation in the geological past. Long-chain n-alkanes are produced in the leaf waxes of terrestrial higher plants and have been shown to preserve the hydrogen isotope composition of precipitation being influenced by atmospheric moisture source, evaporation as well as plant physiology. Since δD values are determined directly on carbon-bound hydrogen, which is non-exchangeable even at higher temperatures biological and environmental source conditions can be preserved over geological timescales. Here, we present a record of n-alkane δD values, \\( nC27 - nC31 \\), from the Ammersee, southern Germany and Lac d'Annecy, French Alps spanning the time period from the Oldest Dryas to Preboreal (14 ka to 11 ka BP). We compare biomarker hydrogen isotopic signatures to oxygen-isotope ratios of precipitation inferred from deep-lake ostracods from the Ammersee as well to GRIP \\(δ18\\)O values. The remarkable climate shift at the onset of the Younger Dryas (YD) (12.9 to 11.6 ka BP) is recorded in the \\(δ18\\)O values as well as the hydrogen isotope signal with a pronounced drop of approx. - 40‰ in D at the Ammersee and a minor negative excursion of - (20‰) in D at Lac d'Annecy. This depletion is consistent with a colder and dryer climate and the expansion of grasslands in the lake catchments as recorded in a significant increase of grass-derived \\( nC31 \\). A sudden remarkable deuterium enrichment of about 100‰ in D is apparent in both lakes and marks the mid-Younger Dryas event (MYDE), which is also reflected in the GRIP and Ammersee \\(δ18\\)O values. δD values during this event reach or even exceed the following Holocene level. The simultaneous appearance of this event in different locations suggests a climate driven by mechanisms like the

  7. Calcareous nannoplankton during Oceanic Anoxic Event 2 (Cenomanian/Turonian boundary) - exceptionally-preserved records from the Tanzania Drilling Project

    NASA Astrophysics Data System (ADS)

    Lees, J. A.; Bown, P. R.; Jimenez Berrocoso, A.; Huber, B. T.; MacLeod, K. G.; Robinson, S. A.

    2009-12-01

    In 2007 and 2009, the Tanzania Drilling Project (TDP) recovered a total of five coreholes from the south-eastern coastal region, around the village of Lindi, that contain the isotope excursion (based on bulk δ13Corg) associated with Oceanic Anoxic Event 2 (OAE2) at the Cenomanian/Turonian boundary. These holes provide expanded successions of a shallowly-buried, predominantly claystone facies that have preserved the calcite component exceptionally well. Calcareous nannoplankton (primary-producers at the base of the oceanic food-chain) preservation in the TDP holes is exceptional, with continuous representation of small and delicate nannofossil taxa, thus affording us the opportunity to shed more light onto the evolutionary record and environmental conditions across this interval of carbon-cycle perturbation that included warming, sea-level rise and extinction. This borehole material allows us to overcome the difficulties faced by previous attempts to document changes in the nannofossil assemblages through OAE2 that were hampered by insufficient temporal resolution, and the poor preservation of fossils due to widespread occurrences of chalk and non-calcareous black shales. Here, we will present new calcareous nannoplankton data from TDP Sites 21, 24, 24B, 26 and 36. Our data show a significant shift in assemblage composition and diversity, accompanied by extinction events, coincident with the first peak of the isotope excursion. These may suggest an onset/increase in oligotrophic marine conditions in that interval.

  8. Design, development and experimental validation of a non-invasive device for recording respiratory events during bottle feeding.

    PubMed

    Cavaiola, C; Tamilia, E; Massaroni, C; Morbidoni, G; Schena, E; Formica, D; Taffoni, F

    2014-01-01

    In newborns, a poor coordination between sucking, swallowing and breathing may undermine the effectiveness of oral feeding and signal immaturity of Central Nervous System. The aim of this work is to develop and validate a non-invasive device for recording respiratory events of newborns during bottle feeding. The proposed device working principle is based on the convective heat exchanged between two hot bodies and the infants' breathing. The sensing elements are inserted into a duct and the gas exchanged by infants is conveyed into this duct thanks to an ad hoc designed system to be mounted on a commercial feeding bottle. Two sets of experiments have been carried out in order to investigate the discrimination threshold of the device and characterize the sensor response at oscillating flows. The effect of distance and tilt between nostrils and device, and the breathing frequency, have been investigated simulating nostrils and neonatal respiratory pattern. The device has a discrimination threshold lower than 0.5 L/min at both 10° and 20° of tilt. Distance for these two settings does not affect the threshold in the investigated range (10-20 mm). Moreover, the device is able to detect breathing events, and to discriminate the onset of expiratory phase, during a neonatal respiratory task delivered by a lung simulator. The results foster the successful application of this device to the assessment of the temporal breathing pattern of newborns during bottle feeding with a non-invasive approach.

  9. Leveraging Food and Drug Administration Adverse Event Reports for the Automated Monitoring of Electronic Health Records in a Pediatric Hospital

    PubMed Central

    Tang, Huaxiu; Solti, Imre; Kirkendall, Eric; Zhai, Haijun; Lingren, Todd; Meller, Jaroslaw; Ni, Yizhao

    2017-01-01

    The objective of this study was to determine whether the Food and Drug Administration’s Adverse Event Reporting System (FAERS) data set could serve as the basis of automated electronic health record (EHR) monitoring for the adverse drug reaction (ADR) subset of adverse drug events. We retrospectively collected EHR entries for 71 909 pediatric inpatient visits at Cincinnati Children’s Hospital Medical Center. Natural language processing (NLP) techniques were used to identify positive diseases/disorders and signs/symptoms (DDSSs) from the patients’ clinical narratives. We downloaded all FAERS reports submitted by medical providers and extracted the reported drug-DDSS pairs. For each patient, we aligned the drug-DDSS pairs extracted from their clinical notes with the corresponding drug-DDSS pairs from the FAERS data set to identify Drug-Reaction Pair Sentences (DRPSs). The DRPSs were processed by NLP techniques to identify ADR-related DRPSs. We used clinician annotated, real-world EHR data as reference standard to evaluate the proposed algorithm. During evaluation, the algorithm achieved promising performance and showed great potential in identifying ADRs accurately for pediatric patients. PMID:28634427

  10. Patient safety events in out-of-hospital paediatric airway management: a medical record review by the CSI-EMS

    PubMed Central

    Hansen, Matthew; Meckler, Garth; Lambert, William; Dickinson, Caitlin; Dickinson, Kathryn; Van Otterloo, Joshua

    2016-01-01

    Objective To describe the frequency and characterise the nature of patient safety events in paediatric out-of-hospital airway management. Methods We conducted a retrospective cross-sectional medical record review of all ‘lights and sirens’ emergency medicine services transports from 2008 to 2011 in patients <18 years of age in the Portland Oregon metropolitan area. A chart review tool (see online supplementary appendix) was adapted from landmark patient safety studies and revised after pilot testing. Expert panels of physicians and paramedics performed blinded reviews of each chart, identified safety events and described their nature. The primary outcomes were presence and severity of patient safety events related to airway management including oxygen administration, bag-valve-mask ventilation (BVM), airway adjuncts and endotracheal intubation (ETI). 10.1136/bmjopen-2016-012259.supp1 supplementary appendix Results From the 11 328 paediatric transports during the study period, there were 497 ‘lights and sirens’ (code 3) transports (4.4%). 7 transports were excluded due to missing data. Of the 490 transports included in the analysis, 329 had a total of 338 airway management procedures (some had more than 1 procedure): 61.6% were treated with oxygen, 15.3% with BVM, 8.6% with ETI and 2% with airway adjuncts. The frequency of errors was: 21% (71/338) related to oxygen use, 9.8% (33/338) related to BVM, 9.5% (32/338) related to intubation and 0.9% (3/338) related to airway adjunct use. 58% of intubations required 3 or more attempts or failed altogether. Cardiac arrest was associated with higher odds of a severe error. Conclusions Errors in paediatric out-of-hospital airway management are common, especially in the context of intubations and during cardiac arrest. PMID:27836871

  11. Proxy records of Late Holocene climate events in the eastern United States: Medieval Warm Period and Little Ice Age

    NASA Astrophysics Data System (ADS)

    Willard, D. A.; Cronin, T. M.; Hayo, K. M.

    2006-12-01

    We are conducting a multiproxy, regional reconstruction of climate variability during the last two millennia including the Medieval Warm Period (MWP) and Little Ice Age (LIA) in eastern North America. Pollen, benthic foraminifers, ostracodes, and other proxies were analyzed from high-resolution sampling of continuous sedimentary records from lakes, wetlands, and estuaries in Florida, North Carolina, Chesapeake Bay, and Lake Champlain. These records document multi-decadal changes in vegetation, temperature, precipitation, and estuarine salinity across a latitudinal transect. During both the MWP and LIA, decreased precipitation altered plant community composition and distribution in the southeastern United States, and the LIA triggered threshold changes in vegetation that persisted until anthropogenic land-cover change overwhelmed the climate signature. In the mid-Atlantic region, progressively cooler and wetter late Holocene springs culminated in a cool, wet LIA; this trend correlates with observed oceanic changes. Trend analysis of the data suggest that inter-regional correlation of multi-decadal and centennial-scale Holocene climate events will be forthcoming.

  12. Variability in recording and scoring of respiratory events during sleep in Europe: a need for uniform standards.

    PubMed

    Arnardottir, Erna S; Verbraecken, Johan; Gonçalves, Marta; Gjerstad, Michaela D; Grote, Ludger; Puertas, Francisco Javier; Mihaicuta, Stefan; McNicholas, Walter T; Parrino, Liborio

    2016-04-01

    Uniform standards for the recording and scoring of respiratory events during sleep are lacking in Europe, although many centres follow the published recommendations of the American Academy of Sleep Medicine. The aim of this study was to assess the practice for the diagnosis of sleep-disordered breathing throughout Europe. A specially developed questionnaire was sent to representatives of the 31 national sleep societies in the Assembly of National Sleep Societies of the European Sleep Research Society, and a total of 29 countries completed the questionnaire. Polysomnography was considered the primary diagnostic method for sleep apnea diagnosis in 10 (34.5%), whereas polygraphy was used primarily in six (20.7%) European countries. In the remaining 13 countries (44.8%), no preferred methodology was used. Fifteen countries (51.7%) had developed some type of national uniform standards, but these standards varied significantly in terms of scoring criteria, device specifications and quality assurance procedures between countries. Only five countries (17.2%) had published these standards. Most respondents supported the development of uniform recording and scoring criteria for Europe, which might be based partly on the existing American Academy of Sleep Medicine rules, but also take into account differences in European practice when compared to North America. This survey highlights the current varying approaches to the assessment of patients with sleep-disordered breathing throughout Europe and supports the need for the development of practice parameters in the assessment of such patients that would be suited to European clinical practice.

  13. Hippocampal negative event-related potential recorded in humans during a simple sensorimotor task occurs independently of motor execution.

    PubMed

    Roman, Robert; Brázdil, Milan; Chládek, Jan; Rektor, Ivan; Jurák, Pavel; Světlák, Miroslav; Damborská, Alena; Shaw, Daniel J; Kukleta, Miloslav

    2013-12-01

    A hippocampal-prominent event-related potential (ERP) with a peak latency at around 450 ms is consistently observed as a correlate of hippocampal activity during various cognitive tasks. Some intracranial EEG studies demonstrated that the amplitude of this hippocampal potential was greater in response to stimuli requiring an overt motor response, in comparison with stimuli for which no motor response is required. These findings could indicate that hippocampal-evoked activity is related to movement execution as well as stimulus evaluation and associated memory processes. The aim of the present study was to investigate the temporal relationship between the hippocampal negative potential latency and motor responses. We analyzed ERPs recorded with 22 depth electrodes implanted into the hippocampi of 11 epileptic patients. Subjects were instructed to press a button after the presentation of a tone. All investigated hippocampi generated a prominent negative ERP peaking at ~420 ms. In 16 from 22 cases, we found that the ERP latency did not correlate with the reaction time; in different subjects, this potential could either precede or follow the motor response. Our results indicate that the hippocampal negative ERP occurs independently of motor execution. We suggest that hippocampal-evoked activity, recorded in a simple sensorimotor task, is related to the evaluation of stimulus meaning within the context of situation.

  14. Is detection of adverse events affected by record review methodology? an evaluation of the "Harvard Medical Practice Study" method and the "Global Trigger Tool".

    PubMed

    Unbeck, Maria; Schildmeijer, Kristina; Henriksson, Peter; Jürgensen, Urban; Muren, Olav; Nilsson, Lena; Pukk Härenstam, Karin

    2013-04-15

    There has been a theoretical debate as to which retrospective record review method is the most valid, reliable, cost efficient and feasible for detecting adverse events. The aim of the present study was to evaluate the feasibility and capability of two common retrospective record review methods, the "Harvard Medical Practice Study" method and the "Global Trigger Tool" in detecting adverse events in adult orthopaedic inpatients. We performed a three-stage structured retrospective record review process in a random sample of 350 orthopaedic admissions during 2009 at a Swedish university hospital. Two teams comprised each of a registered nurse and two physicians were assigned, one to each method. All records were primarily reviewed by registered nurses. Records containing a potential adverse event were forwarded to physicians for review in stage 2. Physicians made an independent review regarding, for example, healthcare causation, preventability and severity. In the third review stage all adverse events that were found with the two methods together were compared and all discrepancies after review stage 2 were analysed. Events that had not been identified by one of the methods in the first two review stages were reviewed by the respective physicians. Altogether, 160 different adverse events were identified in 105 (30.0%) of the 350 records with both methods combined. The "Harvard Medical Practice Study" method identified 155 of the 160 (96.9%, 95% CI: 92.9-99.0) adverse events in 104 (29.7%) records compared with 137 (85.6%, 95% CI: 79.2-90.7) adverse events in 98 (28.0%) records using the "Global Trigger Tool". Adverse events "causing harm without permanent disability" accounted for most of the observed difference. The overall positive predictive value for criteria and triggers using the "Harvard Medical Practice Study" method and the "Global Trigger Tool" was 40.3% and 30.4%, respectively. More adverse events were identified using the "Harvard Medical Practice Study

  15. Is detection of adverse events affected by record review methodology? an evaluation of the “Harvard Medical Practice Study” method and the “Global Trigger Tool”

    PubMed Central

    2013-01-01

    Background There has been a theoretical debate as to which retrospective record review method is the most valid, reliable, cost efficient and feasible for detecting adverse events. The aim of the present study was to evaluate the feasibility and capability of two common retrospective record review methods, the “Harvard Medical Practice Study” method and the “Global Trigger Tool” in detecting adverse events in adult orthopaedic inpatients. Methods We performed a three-stage structured retrospective record review process in a random sample of 350 orthopaedic admissions during 2009 at a Swedish university hospital. Two teams comprised each of a registered nurse and two physicians were assigned, one to each method. All records were primarily reviewed by registered nurses. Records containing a potential adverse event were forwarded to physicians for review in stage 2. Physicians made an independent review regarding, for example, healthcare causation, preventability and severity. In the third review stage all adverse events that were found with the two methods together were compared and all discrepancies after review stage 2 were analysed. Events that had not been identified by one of the methods in the first two review stages were reviewed by the respective physicians. Results Altogether, 160 different adverse events were identified in 105 (30.0%) of the 350 records with both methods combined. The “Harvard Medical Practice Study” method identified 155 of the 160 (96.9%, 95% CI: 92.9-99.0) adverse events in 104 (29.7%) records compared with 137 (85.6%, 95% CI: 79.2-90.7) adverse events in 98 (28.0%) records using the “Global Trigger Tool”. Adverse events “causing harm without permanent disability” accounted for most of the observed difference. The overall positive predictive value for criteria and triggers using the “Harvard Medical Practice Study” method and the “Global Trigger Tool” was 40.3% and 30.4%, respectively. Conclusions More adverse

  16. Identification of Adverse Drug Events from Free Text Electronic Patient Records and Information in a Large Mental Health Case Register

    PubMed Central

    Jackson, Richard George; Ball, Michael; Ibrahim, Zina M.; Broadbent, Matthew; Dzahini, Olubanke; Stewart, Robert; Johnston, Caroline; Dobson, Richard J. B.

    2015-01-01

    Objectives Electronic healthcare records (EHRs) are a rich source of information, with huge potential for secondary research use. The aim of this study was to develop an application to identify instances of Adverse Drug Events (ADEs) from free text psychiatric EHRs. Methods We used the GATE Natural Language Processing (NLP) software to mine instances of ADEs from free text content within the Clinical Record Interactive Search (CRIS) system, a de-identified psychiatric case register developed at the South London and Maudsley NHS Foundation Trust, UK. The tool was built around a set of four movement disorders (extrapyramidal side effects [EPSEs]) related to antipsychotic therapy and rules were then generalised such that the tool could be applied to additional ADEs. We report the frequencies of recorded EPSEs in patients diagnosed with a Severe Mental Illness (SMI) and then report performance in identifying eight other unrelated ADEs. Results The tool identified EPSEs with >0.85 precision and >0.86 recall during testing. Akathisia was found to be the most prevalent EPSE overall and occurred in the Asian ethnic group with a frequency of 8.13%. The tool performed well when applied to most of the non-EPSEs but least well when applied to rare conditions such as myocarditis, a condition that appears frequently in the text as a side effect warning to patients. Conclusions The developed tool allows us to accurately identify instances of a potential ADE from psychiatric EHRs. As such, we were able to study the prevalence of ADEs within subgroups of patients stratified by SMI diagnosis, gender, age and ethnicity. In addition we demonstrated the generalisability of the application to other ADE types by producing a high precision rate on a non-EPSE related set of ADE containing documents. Availability The application can be found at http://git.brc.iop.kcl.ac.uk/rmallah/dystoniaml. PMID:26273830

  17. The Irish National Adverse Events Study (INAES): the frequency and nature of adverse events in Irish hospitals-a retrospective record review study.

    PubMed

    Rafter, Natasha; Hickey, Anne; Conroy, Ronan M; Condell, Sarah; O'Connor, Paul; Vaughan, David; Walsh, Gillian; Williams, David J

    2017-02-01

    Irish healthcare has undergone extensive change recently with spending cuts and a focus on quality initiatives; however, little is known about adverse event occurrence. To assess the frequency and nature of adverse events in Irish hospitals. 1574 (53% women, mean age 54 years) randomly selected adult inpatient admissions from a sample of eight hospitals, stratified by region and size, across the Republic of Ireland in 2009 were reviewed using two-stage (nurse review of patient charts, followed by physician review of triggered charts) retrospective chart review with electronic data capture. Results were weighted to reflect the sampling strategy. The impact on adverse event rate of differing application of international adverse event criteria was also examined. 45% of charts were triggered. The prevalence of adverse events in admissions was 12.2% (95% CI 9.5% to 15.5%), with an incidence of 10.3 events per 100 admissions (95% CI 7.5 to 13.1). Over 70% of events were considered preventable. Two-thirds were rated as having a mild-to-moderate impact on the patient, 9.9% causing permanent impairment and 6.7% contributing to death. A mean of 6.1 added bed days was attributed to events, representing an expenditure of €5550 per event. The adverse event rate varied substantially (8.6%-17.0%) when applying different published adverse event eligibility criteria. This first study of adverse events in Ireland reports similar rates to other countries. In a time of austerity, adverse events in adult inpatients were estimated to cost over €194 million. These results provide important baseline data on the adverse event burden and, alongside web-based chart review, provide an incentive and methodology to monitor future patient-safety initiatives. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  18. Hyperimmune globulins and same-day thrombotic adverse events as recorded in a large healthcare database during 2008-2011.

    PubMed

    Menis, Mikhail; Sridhar, Gayathri; Selvam, Nandini; Ovanesov, Mikhail V; Divan, Hozefa A; Liang, Yideng; Scott, Dorothy; Golding, Basil; Forshee, Richard; Ball, Robert; Anderson, Steven A; Izurieta, Hector S

    2013-12-01

    Thrombotic events (TEs) are rare serious complications following administration of hyperimmune globulin (HIG) products. Our retrospective claims-based study assessed occurrence of same-day TEs following administration of HIGs during 2008-2011 and examined potential risk factors using HealthCore's Integrated Research Database (HIRD(SM) ) and laboratory testing of products' procoagulant Factor XIa activity by U.S. Food and Drug Administration. Multivariable regression was used to estimate same-day TE risk for different products. Of 101,956 individuals exposed to 23 different HIG product groups, 86 (0.84 per 1,000 persons) had a TE diagnosis code (DC) recorded on the same day as HIG administration. Unadjusted same-day TE DC rates (per 1,000 persons) ranged from 0.4 to 148.9 for different products. GamaSTAN S/D IG >10 cc had statistically significantly higher same-day TE DC risk compared to Tetanus IG (OR = 57.57; 95% CI = 19.72-168.10). Increased TE risk was also observed with older age (≥45 years), prior thrombotic events, and hypercoagulable state(s). Laboratory investigation identified elevated Factor XIa activity for GamaSTAN S/D, HepaGam B, HyperHep B S/D, WinRho SDF, HyperRHO S/D full dose, and HyperTET S/D. Our study, for the first time, identified increase in the same-day TE DC risk with GamaSTAN S/D IG >10 cc and suggests potentially elevated TE risk with other HIGs. Copyright © 2013 Wiley Periodicals, Inc.

  19. A comparison of recording modalities of P300 event-related potentials (ERP) for brain-computer interface (BCI) paradigm.

    PubMed

    Mayaud, L; Congedo, M; Van Laghenhove, A; Orlikowski, D; Figère, M; Azabou, E; Cheliout-Heraut, F

    2013-10-01

    A brain-computer interface aims at restoring communication and control in severely disabled people by identification and classification of EEG features such as event-related potentials (ERPs). The aim of this study is to compare different modalities of EEG recording for extraction of ERPs. The first comparison evaluates the performance of six disc electrodes with that of the EMOTIV headset, while the second evaluates three different electrode types (disc, needle, and large squared electrode). Ten healthy volunteers gave informed consent and were randomized to try the traditional EEG system (six disc electrodes with gel and skin preparation) or the EMOTIV Headset first. Together with the six disc electrodes, a needle and a square electrode of larger surface were simultaneously recording near lead Cz. Each modality was evaluated over three sessions of auditory P300 separated by one hour. No statically significant effect was found for the electrode type, nor was the interaction between electrode type and session number. There was no statistically significant difference of performance between the EMOTIV and the six traditional EEG disc electrodes, although there was a trend showing worse performance of the EMOTIV headset. However, the modality-session interaction was highly significant (P<0.001) showing that, while the performance of the six disc electrodes stay constant over sessions, the performance of the EMOTIV headset drops dramatically between 2 and 3h of use. Finally, the evaluation of comfort by participants revealed an increasing discomfort with the EMOTIV headset starting with the second hour of use. Our study does not recommend the use of one modality over another based on performance but suggests the choice should be made on more practical considerations such as the expected length of use, the availability of skilled labor for system setup and above all, the patient comfort. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  20. Carbon isotope records reveal synchronicity between carbon cycle perturbation and the "Carnian Pluvial Event" in the Tethys realm (Late Triassic)

    NASA Astrophysics Data System (ADS)

    Dal Corso, Jacopo; Gianolla, Piero; Newton, Robert J.; Franceschi, Marco; Roghi, Guido; Caggiati, Marcello; Raucsik, Béla; Budai, Tamás; Haas, János; Preto, Nereo

    2015-04-01

    In the early Late Triassic a period of increased rainfall, named the Carnian Pluvial Event (CPE), is evidenced by major lithological changes in continental and marine successions worldwide. The environmental change seems to be closely associated with a negative carbon isotope excursion that was identified in a stratigraphic succession of the Dolomites (Italy) but the temporal relationship between these phenomena is still not well defined. Here we present organic-carbon isotope data from Carnian deep-water stratigraphic sections in Austria and Hungary, and carbonate petrography of samples from a marginal marine section in Italy. A negative 2-4‰ δ13C shift is recorded by bulk organic matter in the studied sections and is coincident with a similar feature highlighted in higher plant and marine algal biomarker carbon-isotope records from the Dolomites (Italy), thus testifying to a global change in the isotopic composition of the reservoirs of the exchangeable carbon. Our new observations verify that sedimentological changes related to the CPE coincide with the carbon cycle perturbation and therefore occurred synchronously within the western Tethys. Consistent with modern observations, our results show that the injection of 13C-depleted CO2 into the Carnian atmosphere-ocean system may have been directly responsible for the increase in rainfall by intensifying the Pangaean mega-monsoon activity. The consequent increased continental weathering and erosion led to the transfer of large amounts of siliciclastics into the basins that were rapidly filled up, while the increased nutrient flux triggered the local development of anoxia. The new carbonate petrography data show that these changes also coincided with the demise of platform microbial carbonate factories and their replacement with metazoan driven carbonate deposition. This had the effect of considerably decreasing carbonate deposition in shallow water environments.

  1. Middle Wisconsin glaciation in the Genesee Valley, NY: A stratigraphic record contemporaneous with Heinrich Event, H4

    NASA Astrophysics Data System (ADS)

    Young, Richard A.; Burr, George S.

    2006-04-01

    Two lacustrine deformation tills with ages corresponding closely to North Atlantic Heinrich event, H4, are preserved in the Genesee Valley on the western edge of the Finger Lakes region of New York State. The locality is at the convergence of a major north-flowing river with the Laurentide ice sheet and results in unusual preservation of datable organics. Intact Middle and Late Wisconsin glacial sequences are preserved above a Middle Wisconsin interstadial disconformity within a bedrock trough that has dimensions similar to those of the larger Finger Lakes. The shallow burial depth and age of the disconformity (circa 35,000 14C years BP) demonstrate that deep erosion of Finger Lakes bedrock troughs cannot be presumed to have occurred during all major glacial advances. The preserved glacial stratigraphy indicates that proglacial and substrate conditions, as well as the rate of ice advance, may cause a wide variation in the ability of ice sheets to cause deep basal erosion during major glacial stadials. The evidence also demonstrates that Middle Wisconsin ice advanced more than 30 km south of the Lake Ontario shoreline in west-central New York. Other buried wood of Middle Wisconsin age in the Genesee Valley suggests that the recoverable record of Early(?) and Middle Wisconsin glaciations in New York is more diverse than is documented in the existing literature.

  2. Skeletal isotope records of growth perturbations in Porites corals during the 1997-1998 mass bleaching event

    NASA Astrophysics Data System (ADS)

    Suzuki, A.; Gagan, M.; Fabricius, K.; Isdale, P.; Yukino, I.; Kawahata, H.

    2003-04-01

    Severe coral bleaching occurred throughout the tropics in 1997/98. We report skeletal UV fluorescence, oxygen isotope, and carbon isotope evidence for perturbations in coral skeletal growth due to bleaching at Ishigaki Island, Japan, and Pandora Reef, Great Barrier Reef. Bleached corals showed abrupt reductions in skeletal extension rate immediately after summer temperature maxima, indicating that bleaching inhibits coral calcification. A colony growing at the low tide line in Ishigaki exhibited clear blue UV fluorescent bands associated with recurrent growth interruptions. Based on the length of time-gaps observed in the annual isotopic cycle, the typical time required for a coral to recover from bleaching is estimated to be about 5--6 months. The effect of bleaching on the oxygen isotope ratio -- temperature relationship was negligible. However, the Ishigaki corals showed lower carbon isotope ratios during bleaching indicating depressed coral metabolism associated with a reduction in calcification. In contrast, skeletal carbon isotope ratios in the Pandora Reef corals exhibited little change in response to bleaching. This is because the records for Pandora Reef were derived from the shaded sides of coral colonies, where algal photosynthesis was particularly slow prior to bleaching, thus subduing the carbon isotope response to bleaching. Taken together, the isotopic and UV fluorescence signals can be used to reconstruct past bleaching events.

  3. RETRACTED: Extreme oceanographic events recorded in the southwest coast of India during the 1998-1999 summer season

    NASA Astrophysics Data System (ADS)

    Krishna, K. Muni

    2010-01-01

    This article has been removed at the request of the Editor-in-chief and Author. Please see Elsevier Policy on Article Withdrawal ( http://www.elsevier.com/locate/withdrawalpolicy). Reason: This article has been retracted at the request of the Editor-in-Chief and Author as the author has plagiarized part of a paper that had already appeared in another journal, as written by the following authors: Roy, Weeks, Rouault, Nelson, Barlow, Van der Lingen. "Extreme oceanographic events recorded in the Southern Benguela during the 1999-2000 summer season", South African J. Sci., 2001, volume 97 (11-12), pp. 465-471. While the underlying scientific data of Dr Krishna's work may be original, the wording, sentence, and paragraph structure of the entire manuscript shows such strong similarity (in many cases wholesale replication of sentences and phrases) that we must conclude that there has been excessive use of previously published material without appropriate attribution and is consequently not an original contribution. One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and we apologize to readers of the journal that this was not detected during the submission process.

  4. Salivary cortisol and interpersonal functioning: an event-contingent recording study in the offspring of parents with bipolar disorder.

    PubMed

    Ellenbogen, Mark A; Linnen, Anne-Marie; Santo, Jonathan B; aan het Rot, Marije; Hodgins, Sheilagh; Young, Simon N

    2013-07-01

    Despite a large body of research in non-human primates, the relationship between naturalistic patterns of social behaviour and basal cortisol levels has been understudied in humans. The present study examined the relationship between patterns of interpersonal functioning and cortisol levels in 23 offspring of parents with bipolar disorder (BD), at high risk for the development of an affective disorder, and 22 offspring of parents with no affective disorder (controls) in late adolescence and young adulthood. Using event-contingent recording, participants rated their dominance, submissiveness, quarrelsomeness, and agreeableness in naturally occurring social interactions over 14 consecutive days and provided salivary cortisol twice daily in the afternoon over the same period. In the full sample, multilevel modelling analyses revealed that dominance was a significant positive predictor of afternoon basal cortisol levels, t(35)=2.58, p<0.05. Moreover, risk group (having a parent with BD or parents with no affective disorder) significantly interacted with mean levels of quarrelsomeness to predict afternoon cortisol levels, t(29)=2.06, p<0.05. Offspring of parents with BD who reported more frequent quarrelsome behaviours exhibited lower levels of afternoon cortisol relative to high-risk offspring reporting few quarrelsome behaviours and control offspring. The results are consistent with evidence that dominance is associated with high cortisol levels in an unstable environment, and suggest that quarrelsomeness among high risk youth contributes to altered hypothalamic-pituitary-adrenal activity.

  5. Seasonality and Disturbance Events in the Carbon Isotope Record of Pinus elliottii Tree Rings from Big Pine Key, Florida

    NASA Astrophysics Data System (ADS)

    Rebenack, C.; Anderson, W. T.; Cherubini, P.

    2012-12-01

    The South Florida coastal ecosystem is among the world's subtropical coastlines which are threatened by the potential effects of climate change. A well-developed localized paleohistory is essential in the understanding of the role climate variability/change has on both hydrological dynamics and disturbance event frequency and intensity; this understanding can then aid in the development of better predictive models. High resolution paleoclimate proxies, such as those developed from tree-ring archives, may be useful tools for extrapolating actual climate trends over time from the overlapping long-term and short-term climate cycles, such as the Atlantic Multidecadal Oscillation (AMO) and the El Niño-Southern Oscillation (ENSO). In South Florida, both the AMO and ENSO strongly influence seasonal precipitation, and a more complete grasp of how these cycles have affected the region in the past could be applied to future freshwater management practices. Dendrochronology records for the terrestrial subtropics, including South Florida, are sparse because seasonality for this region is precipitation-driven; this is in contrast to the drastic temperature changes experienced in the temperate latitudes. Subtropical seasonality may lead to the complete lack of visible rings or to the formation of ring structures that may or may not represent annual growth. Fortunately, it has recently been demonstrated that Pinus elliottii trees in South Florida produce distinct annual growth rings; however ring width was not found to significantly correlate with either the AMO or ENSO. Dendrochronology studies may be taken a step beyond the physical tree-ring proxies by using the carbon isotope ratios to infer information about physiological controls and environmental factors that affect the distribution of isotopes within the plant. It has been well established that the stable isotope composition of cellulose can be related to precipitation, drought, large-scale ocean/atmospheric oscillations

  6. Impaired Fasting Glucose And The Risk Of Incident Diabetes Mellitus And Cardiovascular Events In An Adult Population: The Multi-Ethnic Study of Atherosclerosis

    PubMed Central

    Yeboah, Joseph; Bertoni, Alain G; Herrington, David M; Post, Wendy S; Burke, Gregory L

    2011-01-01

    Objective To assess the cardiovascular risk of impaired fasting glucose (IFG). Background The association between IFG, incident type 2 diabetes mellitus (T2DM) and cardiovascular (CV) events remains unclear. Methods The Multi-Ethnic Study of Atherosclerosis (MESA) included participants aged 45–84 free of clinical CV disease at baseline (2000–2002). T2DM was defined as fasting glucose >125mg/dl or anti-diabetes medication at baseline and follow-up exams, IFG as no T2DM and fasting glucose 100–125.mg/dl. Cox proportional hazard analysis was used to assess the association between IFG and incident DM and also with incident CV events. Results Of 6753 participants included in these analyses 840 (12.7%) had T2DM, 940 (13.8%) had IFG at the baseline exam. During 7.5 years of follow-up there were 418 adjudicated CV events. T2DM was associated with an increased CV incidence in the univariate [hazard ratio (HR); 2.83(2.25–3.56), p<0.0001] and multivariable models (adjusted for demographics and traditional risk factors) [HR; 1.87(1.47 – 2.37), p<0.0001] compared with subjects without T2DM (IFG + NFG). IFG was associated with increased incidence of T2DM [HR; 13.2 (95%CI 10.8–16.2), p<0.001] that remained after adjusting for demographics, highest educational level, physical activity and BMI [HR; 10.5(8.4–13.1), p<0.001] compared to NFG. IFG was associated with incident CV events in the univariate [HR; 1.64(1.26 – 2.14), p=<0.001] but not in the full multivariable model [HR; 1.16(95% CI 0.88–1.52), p=0.3] compared with NFG. Conclusion Having IFG was not independently associated with an increased short-term risk for incident CV events. These data reiterate the importance of intervention in persons with IFG to reduce their incidence of T2DM. PMID:21718910

  7. Coeval dry events in the central and eastern Mediterranean basin at 5.2 and 5.6 ka recorded in Corchia (Italy) and Soreq caves (Israel) speleothems

    NASA Astrophysics Data System (ADS)

    Zanchetta, G.; Bar-Matthews, M.; Drysdale, R. N.; Lionello, P.; Ayalon, A.; Hellstrom, J. C.; Isola, I.; Regattieri, E.

    2014-11-01

    Soreq (Israel) and Corchia (central Italy) Caves are located 2500 km far apart along the Mediterranean winter-storm track and are ideally suited for investigating past variations of winter rainfall in the Mediterranean region. Analyses of speleothem δ18O records from both caves for the period between ca. 7 to 4 ka BP show some striking similarities for the ca. 6 and 4 ka interval, but lack agreement between ca. 7 to 6 ka BP. Two prominent isotopic excursions, argued to reflect relatively drier conditions, are centred at ca. 5.6 and ca. 5.2 ka. The 5.2 ka event lasts less than a century, whereas the 5.6 ka event extends from ca. 5.7 to 5.4 ka. A period of progressive drying is also apparent from ca. 5 to 4 ka. Another prominent event, reflecting wetter conditions, is recorded in both records at ca. 5.8 ka and seems to last several decades. The 5.6 and 5.2 ka events occurred within a period of higher deposition of haematite-stained grains in cores of the sub-polar North Atlantic, and correlation with the wind strength proxy record from Hólmsá loess profile in Iceland suggests that rainfall reduction was related to a reduced vapour advection from Atlantic towards the Mediterranean connected to northward shift in the Westerlies. A comparison with Alpine records, including the Spannagel Cave isotope record, suggests that dry events recorded at Soreq and Corchia caves may correspond to wetter (lake high stands) and cooler (glacier expansion) conditions in the Alpine region, indicating complex regional climate re-organization.

  8. Secondary prevention of cardiovascular events with long-term pravastatin in patients with diabetes or impaired fasting glucose: results from the LIPID trial.

    PubMed

    Keech, Anthony; Colquhoun, David; Best, James; Kirby, Adrienne; Simes, R John; Hunt, David; Hague, Wendy; Beller, Elaine; Arulchelvam, Manjula; Baker, Jennifer; Tonkin, Andrew

    2003-10-01

    Diabetes, a major health problem worldwide, increases the risk of cardiovascular disease and its associated mortality: The Long-Term Intervention with Pravastatin in Ischemic Disease (LIPID) trial showed that cholesterol-lowering treatment with pravastatin reduced mortality and coronary heart disease (CHD) events in 9014 patients aged 31-75 years with CHD and total cholesterol 4.0-7.0 mmol/l. We measured the effects of pravastatin therapy, 40 mg/day over 6.0 years, on the risk of CHD death or nonfatal myocardial infarction and other cardiovascular outcomes in 1,077 LIPID patients with diabetes and 940 patients with impaired fasting glucose (IFG). In patients allocated to placebo, the risk of a major CHD event was 61% higher in patients with diabetes and 23% higher in the IFG group than in patients with normal fasting glucose, and the risk of any cardiovascular event was 37% higher in the diabetic group and 19% higher in the IFG group. Pravastatin therapy reduced the risk of a major CHD event overall from 15.9 to 12.3% (relative risk reduction [RRR] 24%, P < 0.001) and from 23.4 to 19.6% in the diabetic group (19%, P = 0.11); in the diabetic group, the reduction was not significantly different from the reductions in the other groups. Pravastatin reduced the risk of any cardiovascular event from 52.7 to 45.2% (21%, P < 0.008) in patients with diabetes and from 45.7 to 37.1% (26%, P = 0.003) in the IFG group. Pravastatin reduced the risk of stroke from 9.9 to 6.3% in the diabetic group (RRR 39%, CI 7-61%, P = 0.02) and from 5.4 to 3.4% in the IFG group (RRR 42%, CI -9 to 69%, P = 0.09). Pravastatin did not reduce the incidence of diabetes. Over 6 years, pravastatin therapy prevented one major CHD event (CHD death or nonfatal myocardial infarction) in 23 patients with IFG and 18 patients with diabetes. A meta-analysis of other major trials confirmed the high absolute risks of diabetes and IFG and the absolute benefits of statin therapy in these patients. Cholesterol

  9. Stable isotope and benthic foraminiferal records of the Latest Danian Event at ODP Site 1262 (Walvis Ridge)

    NASA Astrophysics Data System (ADS)

    Deprez, Arne; Jehle, Sofie; Bornemann, André; Speijer, Robert P.

    2015-04-01

    The Latest Danian Event (LDE - aka Top Chron 27n Event) is characterized by a >1o negative benthic foraminiferal CIE in various sections in Egypt, which has been correlated with δ13C shifts of ~0.7o in Zumaia (Spain), Wombat Plateau (ODP 761B, Indian Ocean) and Shatsky Rise (ODP 1209, Pacific Ocean) (Bornemann et al., 2009; Westerhold et al., 2011). A concurrent ~0.5o δ18O excursion suggests a 2°C bottom water temperature rise during this event at Shatsky Rise, suggesting a hyperthermal nature for this event (Westerhold et al., 2011). Here we show the first results of benthic foraminiferal faunal and isotope patterns related to the LDE at Walvis Ridge (ODP Site 1262, Southern Atlantic Ocean, paleodepth ~3000 m). The high percentage of planktic foraminifera (on average 99.2%) indicates good carbonate preservation. Stable isotope analyses on the benthic foraminifer Nuttallides truempyi show a ~0.9o δ13C shift at ~62.2 Ma. Lowest values are measured at ~62.15 Ma. A concurrent ~0.8o δ18O excursion indicates a ~3°C temperature rise, larger than at Shatsky Rise. δ13C values recover to reach a transient plateau at 0.75o during the second Fe peak (from ~62.1 to 62.0 Ma), coinciding with a second negative δ18O excursion of 0.7o. Also the ODP Site 1209 (Shatsky Rise) record shows these double Fe, δ18O and δ13C peaks. This is a feature that the LDE shares with some early Eocene hyperthermals, like ETM-2/H1-H2 and I1-I2, and might point to a common origin as the early Eocene hyperthermals. The Walvis Ridge samples show a highly diverse assemblage of benthic foraminifera with a relative abundance of 10-15% of Gyroidinoides spp. and ~10% of Nuttallides spp., Siphogenerinoides spp., Gavelinella spp., Epistominella spp. and Cibicidoides spp. The ~15cm sample interval dataset seems to show no large changes in relative abundance of these species at the onset of the LDE. This is different than faunal response to early Eocene hyperthermals, like ETM2. During ETM2 at DSDP

  10. Flooding of the Great River during the Common Era: A Paleohydrological Record of High Magnitude Flood Events from the Central Mississippi River Valley

    NASA Astrophysics Data System (ADS)

    Williams, J. W.; Munoz, S. E.; Gruley, K. E.; Massie, A.

    2014-12-01

    Streamflow characteristics are known to be sensitive to changes in climate, but few continuous records of flooding exist to evaluate the response of hydrological systems to centennial- and millennia-scale climate changes. Here, we present sedimentary records from two oxbow lakes (Horseshoe Lake and Grassy Lake, Illinois, USA) in the central Mississippi River valley (CMRV) that display abrupt shifts in sediment composition and particle-size consistent with deposition by floodwaters immediately following inundation of the floodplain. The sedimentary record at Horseshoe Lake begins ca. AD 100 and displays five major flood events, with four of these occurring after ca. AD 1100. Situated 200 km downstream, the record from Grassy Lake begins later, ca. AD 800, and also shows four major flood events after ca. AD 1100. An analysis of synchronicity using Bayesian age modelling software shows high likelihoods that the four overlapping flood events occurred at the same time, confirming that these events resulted from flooding of the Mississippi River. The most recent event we record at AD 1840 ± 50 corresponds to the AD 1844 flood, the largest flood by discharge (37 m3/s) measured by the gauging station at St. Louis, Missouri, indicating that our sedimentary records document high magnitude flood events. Together, our two sedimentary records show a major shift in the frequency of high magnitude flooding in the central Mississippi River at ca. AD 1100. From AD 100 - AD 1100, only one relatively subtle flood event is recorded, but from AD 1100 - AD 1900, four high magnitude floods deposited distinctive sediment at both sites. The period of infrequent flooding corresponds to a time of agricultural intensification and population growth in the CMRV, while the entire region was abandoned when flood frequency increased. The pronounced shift in flood frequency we observe in our records at ca. AD 1100 begins during the Medieval Climate Anomaly (MCA; AD 950 - AD 1250), a period of

  11. Investigation of Historic Seismic and Infrasound Records from Events Occurred at the Region of Novaya Zemplya Test Site by the USSR Stations

    NASA Astrophysics Data System (ADS)

    Sokolova, Inna

    2014-05-01

    Located in the north the Novaya Zemlya Test Site was used in Soviet time for conducting unique nuclear weapon tests in different mediums. 130 nuclear explosions with total yield 265 megatons were conducted at the Test Site for the period 1955-1990. During this period the following nuclear explosions were conducted: 1 surface explosion, 85 air explosions, 2 above water explosions, 3 underwater explosions and 39 underground explosions (in boreholes and tunnels). In addition, tectonic earthquakes and induced earthquakes caused by multi-megatons UNE occur near the Test Site. Unfortunately, only few seismic events occurred on the territory of the Test Site were recorded by digital stations. However, the archives of different seismological organizations of the USSR contain huge amount of analogue seismograms recorded by permanent and temporary stations. Historical seismograms of nuclear explosions and earthquakes from Novaya Zemlya Test site territory were digitized by the Complex Seismological Expedition IPE RAS and by the Institute of Geophysical Researches RK; a database of the events from the Test Site containing 470 seismograms at epicentral distance 2100-3800 was created. The database includes seismic records of air, underground nuclear explosions, and records of underwater nuclear explosion conducted within "Korall" exercise. In addition, infrasound records of waves from multi-megatons air nuclear explosions recorded by a microbarograph installed at Talgar seismic station at distance ~3600 km from the Test Site were digitized. Kinematic and dynamic parameters of nuclear explosions records conducted in different mediums (air, under water and underground) were investigated by the digitized records from events at Novaya Zemlya Test Site; specific features of wave pattern for each class of events were found.

  12. Adverse Event Recording and Reporting in Clinical Trials Comparing Lumbar Disk Replacement with Lumbar Fusion: A Systematic Review.

    PubMed

    Hiratzka, Jayme; Rastegar, Farbod; Contag, Alec G; Norvell, Daniel C; Anderson, Paul A; Hart, Robert A

    2015-12-01

    Study Design Systematic review. Objectives (1) To compare the quality of adverse event (AE) methodology and reporting among randomized trials comparing lumbar fusion with lumbar total disk replacement (TDR) using established AE reporting systems; (2) to compare the AEs and reoperations of lumbar spinal fusion with those from lumbar TDR; (3) to make recommendations on how to report AEs in randomized controlled trials (RCTs) so that surgeons and patients have more-detailed and comprehensive information when making treatment decisions. Methods A systematic search of PubMed, the Cochrane collaboration database, and the National Guideline Clearinghouse through May 2015 was conducted. Randomized controlled trials with at least 2 years of follow-up comparing lumbar artificial disk replacement with lumbar fusion were included. Patients were required to have axial or mechanical low back pain of ≥3 months' duration due to degenerative joint disease defined as degenerative disk disease, facet joint disease, or spondylosis. Outcomes included the quality of AE acquisition methodology and results reporting, and AEs were defined as those secondary to the procedure and reoperations. Individual and pooled relative risks and their 95% confidence intervals comparing lumbar TDR with fusion were calculated. Results RCTs demonstrated a generally poor description of methods for assessing AEs. There was a consistent lack of clear definition or grading for these events. Furthermore, there was a high degree of variation in reporting of surgery-related AEs. Most studies lacked adequate reporting of the timing of AEs, and there were no clear distinctions between acute or chronic AEs. Meta-analysis of the pooled data demonstrated a twofold increased risk of AEs in patients having lumbar fusion compared with patients having lumbar TDR at 2-year follow-up, and this relative risk was maintained at 5 years. Furthermore, the pooled data demonstrated a 1.7 times greater relative risk of

  13. Accuracy and generalizability of using automated methods for identifying adverse events from electronic health record data: a validation study protocol.

    PubMed

    Rochefort, Christian M; Buckeridge, David L; Tanguay, Andréanne; Biron, Alain; D'Aragon, Frédérick; Wang, Shengrui; Gallix, Benoit; Valiquette, Louis; Audet, Li-Anne; Lee, Todd C; Jayaraman, Dev; Petrucci, Bruno; Lefebvre, Patricia

    2017-02-16

    Adverse events (AEs) in acute care hospitals are frequent and associated with significant morbidity, mortality, and costs. Measuring AEs is necessary for quality improvement and benchmarking purposes, but current detection methods lack in accuracy, efficiency, and generalizability. The growing availability of electronic health records (EHR) and the development of natural language processing techniques for encoding narrative data offer an opportunity to develop potentially better methods. The purpose of this study is to determine the accuracy and generalizability of using automated methods for detecting three high-incidence and high-impact AEs from EHR data: a) hospital-acquired pneumonia, b) ventilator-associated event and, c) central line-associated bloodstream infection. This validation study will be conducted among medical, surgical and ICU patients admitted between 2013 and 2016 to the Centre hospitalier universitaire de Sherbrooke (CHUS) and the McGill University Health Centre (MUHC), which has both French and English sites. A random 60% sample of CHUS patients will be used for model development purposes (cohort 1, development set). Using a random sample of these patients, a reference standard assessment of their medical chart will be performed. Multivariate logistic regression and the area under the curve (AUC) will be employed to iteratively develop and optimize three automated AE detection models (i.e., one per AE of interest) using EHR data from the CHUS. These models will then be validated on a random sample of the remaining 40% of CHUS patients (cohort 1, internal validation set) using chart review to assess accuracy. The most accurate models developed and validated at the CHUS will then be applied to EHR data from a random sample of patients admitted to the MUHC French site (cohort 2) and English site (cohort 3)-a critical requirement given the use of narrative data -, and accuracy will be assessed using chart review. Generalizability will be determined

  14. A High-Resolution Stalagmite Holocene Paleoclimate Record from Northern Venezuela with Insights into the Timing and Duration of the 8.2 ka Event

    NASA Astrophysics Data System (ADS)

    Retrum, J. B.; Gonzalez, L. A.; Edwards, R.; Cheng, H.; Tincher, S. M.; Urbani, F.

    2013-12-01

    The dearth of studies and data in the tropics hinders our understanding of atmospheric and oceanic interactions between the low latitudes and the rest of the globe. To understand better the interactions, specifically between the Caribbean and the North Atlantic, three stalagmites were collected from Cueva Zarraga in the Falcón Mountains of northwestern Venezuela and analyzed to determine local paleoclimatic history. Stalagmites ages were determined by U/Th disequilibrium and show a nearly complete Holocene record. The stalagmites have an average temporal resolution of 10.8 years/mm and ranges from 2.1 to 62.7 years. Both the carbon and oxygen isotope records preserve quasi-millennial oscillations and show a major depletion shift from the last glacial period into the Holocene, suggesting warmer and wetter conditions during the Holocene. The preservation of quasi-millennial oscillations and of high frequency multi-decadal changes by the δ13C indicates that the soil-vegetation-stalagmite system is acting as an amplifier of the climatic signal produced by climatic events and changes. In the early Holocene, the δ18O record shows a depletion trend from ~ 11,000 to 8,000 cal yr BP before reaching the Holocene Thermal Maximum. A prominent δ18O enrichment event is recorded in all the stalagmites that correspond to the 8.2 ka event. The 8.2 ka event is represented by a double peak with duration of ~ 180 years. Other short-term δ18O enrichment events likely correspond to Bond events 1, 2, 5, and 6. The late Holocene record, like other Caribbean records, indicates that the climate system diverges from insolation and may represent an atmospheric rearrangement that resulted in ENSO increase instability or in reduced seasonal movement of the Inter-Tropical Convergence Zone (ITCZ). Today, Cueva Zarraga is at the northern extent of the ITCZ and has two rainy seasons. The δ18O enrichment events during the Holocene suggest drier conditions southern displacement of the ITCZ

  15. Fast adaptation of the internal model of gravity for manual interceptions: evidence for event-dependent learning.

    PubMed

    Zago, Myrka; Bosco, Gianfranco; Maffei, Vincenzo; Iosa, Marco; Ivanenko, Yuri P; Lacquaniti, Francesco

    2005-02-01

    We studied how subjects learn to deal with two conflicting sensory environments as a function of the probability of each environment and the temporal distance between repeated events. Subjects were asked to intercept a visual target moving downward on a screen with randomized laws of motion. We compared five protocols that differed in the probability of constant speed (0g) targets and accelerated (1g) targets. Probability ranged from 9 to 100%, and the time interval between consecutive repetitions of the same target ranged from about 1 to 20 min. We found that subjects systematically timed their responses consistent with the assumption of gravity effects, for both 1 and 0g trials. With training, subjects rapidly adapted to 0g targets by shifting the time of motor activation. Surprisingly, the adaptation rate was independent of both the probability of 0g targets and their temporal distance. Very few 0g trials sporadically interspersed as catch trials during immersive practice with 1g trials were sufficient for learning and consolidation in long-term memory, as verified by retesting after 24 h. We argue that the memory store for adapted states of the internal gravity model is triggered by individual events and can be sustained for prolonged periods of time separating sporadic repetitions. This form of event-related learning could depend on multiple-stage memory, with exponential rise and decay in the initial stages followed by a sample-and-hold module.

  16. One fourth of unplanned transfers to a higher level of care are associated with a highly preventable adverse event: a patient record review in six Belgian hospitals.

    PubMed

    Marquet, Kristel; Claes, Neree; De Troy, Elke; Kox, Gaby; Droogmans, Martijn; Schrooten, Ward; Weekers, Frank; Vlayen, Annemie; Vandersteen, Marjan; Vleugels, Arthur

    2015-05-01

    The objectives of this study are to determine the prevalence and preventability of adverse events requiring an unplanned higher level of care, defined as an unplanned transfer to the ICU or an in-hospital medical emergency team intervention, and to assess the type and the level of harm of each adverse event. A three-stage retrospective review process of screening, record review, and consensus judgment was performed. Six Belgian acute hospitals. During a 6-month period, all patients with an unplanned need for a higher level of care were selected. The records 6-month period, the records of all patients with an unplanned need for a higher level of care were assessed by a trained clinical team consisting of a research nurse, a physician, and a clinical pharmacist. Adverse events were found in 465 of the 830 reviewed patient records (56%). Of these, 215 (46%) were highly preventable. The overall incidence rate of patients being transferred to a higher level of care involving an adverse event was 117.6 (95% CI, 106.9-128.3) per 100,000 patient days at risk, of which 54.4 (95% CI, 47.15-61.65) per 100,000 patient days at risk involving a highly preventable adverse event. This means that 25.9% of all unplanned transfers to a higher level of care were associated with a highly preventable adverse event. The adverse events were mainly associated with drug therapy (25.6%), surgery (23.7%), diagnosis (12.4%), and system issues (12.4%). The level of harm varied from temporary harm (55.7%) to long-term or permanent impairment (19.1%) and death (25.2%). Although the direct causality is often hard to prove, it is reasonable to consider these adverse events as a contributing factor. Adverse events were found in 56% of the reviewed records, of which almost half were considered highly preventable. This means that one fourth of all unplanned transfers to a higher level of care were associated with a highly preventable adverse event.

  17. The 2015/16 El Niño Event as Recorded in Central Tropical Pacific Corals: Temperature, Hydrology, and Ocean Circulation Influences

    NASA Astrophysics Data System (ADS)

    O'Connor, G.; Cobb, K. M.; Sayani, H. R.; Grothe, P. R.; Atwood, A. R.; Stevenson, S.; Hitt, N. T.; Lynch-Stieglitz, J.

    2016-12-01

    The El Niño/Southern Oscillation (ENSO) of 2015/2016 was a record-breaking event in the central Pacific, driving profound changes in the properties of the ocean and atmosphere. Prolonged ocean warming of up to 3°C translated into a large-scale coral bleaching and mortality event on Christmas Island (2°N, 157°W) that very few individuals escaped unscathed. As part of a long-term, interdisciplinary monitoring effort underway since August 2014, we present results documenting the timing and magnitude of environmental changes on the Christmas Island reefs. In particular, we present the first coral geochemical time series spanning the last several years, using cores that were drilled from rare living coral colonies during a field expedition in April 2016, at the tail end of the event. These geochemical indicators are sensitive to both ocean temperature, salinity, and water mass properties and have been used to quantitatively reconstruct ENSO extremes of the recent [Nurhati et al., 2011] and distant [Cobb et al., 2013] past. By analyzing multiple cores from both open ocean and lagoonal settings, we are able to undertake a quantitative comparison of this event with past very strong El Niño events contained in the coral archive - including the 1940/41, 1972/73, and 1997/98 events. For the most recent event, we compare our coral geochemistry records with a rich suite of in situ environmental data, including physical and geochemical parameters collected as part of the NOAA rapid response campaign in the central tropical Pacific. This unique dataset not only provides physical context interpreting coral geochemical records from the central tropical Pacific, but allows us to assess why the 2015/2016 El Niño event was so devastating to coral reef ecosystems in this region.

  18. In-Flight Observations of Long-Term Single-Event Effect (SEE) Performance on X-ray Timing Explorer (XTE) Solid-state Recorders (SSRs)

    NASA Technical Reports Server (NTRS)

    Poivey, Christian; Gee, George; LaBel, Kenneth A.; Barth, Janet L.

    2004-01-01

    We present multi-year Single Event Upset (SEU) flight data on Solid State Recorder (SSR) memories for the X-ray Timing Explorer (XTE) NASA mission. Actual SEU rates are compared to the predicted rates based on ground test data and environment models.

  19. A fast one-chip event-preprocessor and sequencer for the Simbol-X Low Energy Detector

    NASA Astrophysics Data System (ADS)

    Schanz, T.; Tenzer, C.; Maier, D.; Kendziorra, E.; Santangelo, A.

    2010-12-01

    We present an FPGA-based digital camera electronics consisting of an Event-Preprocessor (EPP) for on-board data preprocessing and a related Sequencer (SEQ) to generate the necessary signals to control the readout of the detector. The device has been originally designed for the Simbol-X low energy detector (LED). The EPP operates on 64×64 pixel images and has a real-time processing capability of more than 8000 frames per second. The already working releases of the EPP and the SEQ are now combined into one Digital-Camera-Controller-Chip (D3C).

  20. The Use of Continuous Wavelet Transform Based on the Fast Fourier Transform in the Analysis of Multi-channel Electrogastrography Recordings.

    PubMed

    Komorowski, Dariusz; Pietraszek, Stanislaw

    2016-01-01

    This paper presents the analysis of multi-channel electrogastrographic (EGG) signals using the continuous wavelet transform based on the fast Fourier transform (CWTFT). The EGG analysis was based on the determination of the several signal parameters such as dominant frequency (DF), dominant power (DP) and index of normogastria (NI). The use of continuous wavelet transform (CWT) allows for better visible localization of the frequency components in the analyzed signals, than commonly used short-time Fourier transform (STFT). Such an analysis is possible by means of a variable width window, which corresponds to the scale time of observation (analysis). Wavelet analysis allows using long time windows when we need more precise low-frequency information, and shorter when we need high frequency information. Since the classic CWT transform requires considerable computing power and time, especially while applying it to the analysis of long signals, the authors used the CWT analysis based on the fast Fourier transform (FFT). The CWT was obtained using properties of the circular convolution to improve the speed of calculation. This method allows to obtain results for relatively long records of EGG in a fairly short time, much faster than using the classical methods based on running spectrum analysis (RSA). In this study authors indicate the possibility of a parametric analysis of EGG signals using continuous wavelet transform which is the completely new solution. The results obtained with the described method are shown in the example of an analysis of four-channel EGG recordings, performed for a non-caloric meal.

  1. Separating double-beta decay events from solar neutrino interactions in a kiloton-scale liquid scintillator detector by fast timing

    NASA Astrophysics Data System (ADS)

    Elagin, Andrey; Frisch, Henry J.; Naranjo, Brian; Ouellet, Jonathan; Winslow, Lindley; Wongjirad, Taritree

    2017-03-01

    We present a technique for separating nuclear double beta decay (ββ -decay) events from background neutrino interactions due to 8B decays in the sun. This background becomes dominant in a kiloton-scale liquid-scintillator detector deep underground and is usually considered as irreducible due to an overlap in deposited energy with the signal. However, electrons from 0 νββ -decay often exceed the Cherenkov threshold in liquid scintillator, producing photons that are prompt and correlated in direction with the initial electron direction. The use of large-area fast photodetectors allows some separation of these prompt photons from delayed isotropic scintillation light and, thus, the possibility of reconstructing the event topology. Using a simulation of a 6.5 m radius liquid scintillator detector with 100 ps resolution photodetectors, we show that a spherical harmonics analysis of early-arrival light can discriminate between 0 νββ -decay signal and 8B solar neutrino background events on a statistical basis. Good separation will require the development of a slow scintillator with a 5 ns risetime.

  2. An annually resolved marine proxy record for the 8.2K cold event from the northern North Sea based on bivalve shells

    NASA Astrophysics Data System (ADS)

    Butler, Paul; Estrella-Martínez, Juan; Scourse, James

    2017-04-01

    The so-called 8.2K cold event is a rapid cooling of about 6° +/- 2° recorded in the Greenland ice core record and thought to be a consequence of a freshwater pulse from the Laurentide ice sheet which reduced deepwater formation in the North Atlantic. In the Greenland ice cores the event is characterized by a maximum extent of 159 years and a central event lasting for 70 years. As discussed by Thomas et al (QSR, 2007), the low resolution and dating uncertainty of much palaeoclimate data makes it difficult to determine the rates of change and causal sequence that characterise the event at different locations. We present here a bivalve shell chronology based on four shells of Arctica islandica from the northern North Sea which (within radiocarbon uncertainty) is coeval with the 8.2K event recorded in the Greenland ice cores. The years of death of each shell based on radiocarbon analysis and crossmatching are 8094, 8134, 8147, and 8208 yrs BP (where "present" = AD 1950), with an associated radiocarbon uncertainty of +/-80 yrs, and their longevities are 106, 122, 112 and 79 years respectively. The total length of the chronology is 192 years (8286 - 8094 BP +/- 80 yrs). The most noticeable feature of the chronology is an 60-year period of increasing growth which may correspond to a similar period of decreasing ice accumulation in the GRIP (central Greenland) ice core record. We tentatively suggest that this reflects increasing food supply to the benthos as summer stratification is weakened by colder seawater temperatures. Stable isotope analyses (results expected to be available when this abstract is presented), will show changes at annual and seasonal resolution, potentially giving a very detailed insight into the causal factors associated with the 8.2K event and its impact in the northern North Sea.

  3. iPTF16fnl: A Faint and Fast Tidal Disruption Event in an E+A Galaxy

    NASA Astrophysics Data System (ADS)

    Blagorodnova, N.; Gezari, S.; Hung, T.; Kulkarni, S. R.; Cenko, S. B.; Pasham, D. R.; Yan, L.; Arcavi, I.; Ben-Ami, S.; Bue, B. D.; Cantwell, T.; Cao, Y.; Castro-Tirado, A. J.; Fender, R.; Fremling, C.; Gal-Yam, A.; Ho, A. Y. Q.; Horesh, A.; Hosseinzadeh, G.; Kasliwal, M. M.; Kong, A. K. H.; Laher, R. R.; Leloudas, G.; Lunnan, R.; Masci, F. J.; Mooley, K.; Neill, J. D.; Nugent, P.; Powell, M.; Valeev, A. F.; Vreeswijk, P. M.; Walters, R.; Wozniak, P.

    2017-07-01

    We present ground-based and Swift observations of iPTF16fnl, a likely tidal disruption event (TDE) discovered by the intermediate Palomar Transient Factory (iPTF) survey at 66.6 Mpc. The light curve of the object peaked at an absolute mag {M}g=-17.2. The maximum bolometric luminosity (from optical and UV) was {L}p≃ (1.0+/- 0.15)× {10}43 erg s-1, an order of magnitude fainter than any other optical TDE discovered so far. The luminosity in the first 60 days is consistent with an exponential decay, with L\\propto {e}-(t-{t0)/τ }, where t 0 = 57631.0 (MJD) and τ ≃ 15 days. The X-ray shows a marginal detection at {L}X={2.4}-1.11.9× {10}39 erg s-1 (Swift X-ray Telescope). No radio counterpart was detected down to 3σ, providing upper limits for monochromatic radio luminosities of {ν L}ν < 2.3× {10}36 erg s-1 and {ν L}ν < 1.7× {10}37 erg s-1 (Very Large Array, 6.1 and 22 GHz). The blackbody temperature, obtained from combined Swift UV and optical photometry, shows a constant value of 19,000 K. The transient spectrum at peak is characterized by broad He ii and Hα emission lines, with FWHMs of about 14,000 km s-1 and 10,000 km s-1, respectively. He i lines are also detected at λλ 5875 and 6678. The spectrum of the host is dominated by strong Balmer absorption lines, which are consistent with a post-starburst (E+A) galaxy with an age of ˜650 Myr and solar metallicity. The characteristics of iPTF16fnl make it an outlier on both luminosity and decay timescales, as compared to other optically selected TDEs. The discovery of such a faint optical event suggests a higher rate of tidal disruptions, as low-luminosity events may have gone unnoticed in previous searches.

  4. Cenozoic prograding sequences of the Antarctic continental margin: a record of glacio-eustatic and tectonic events

    USGS Publications Warehouse

    Cooper, A. K.; Barrett, P.J.; Hinz, K.; Traube, V.; Letichenkov, G.; Stagg, H.M.J.

    1991-01-01

    times, like today, by little or no clastic sedimentation on the continental shelf other than beneath retreated ice shelves lying far from the continental sheld edge. Ice streams carve broad depressions across the shelf and carry abundant basal sediments directly to the continental shelf edge, thereby creating troughmouth fans and sheet-like prograding sequences (i.e. type IA sequences). Numerous acoustic unconformities and multiple overcompacted layers within the prograding sequences suggest major fluctuations of the Antarctic Ice Sheet. The available drilling and seismic interpretations provide the following history: (1) Cenozoic ice sheets have existed in places near the continental shelf since middle to late Eocene time. (2) A grounded Antarctic ice sheet first expanded to the continental shelf edge, with probable overdeepening of the outer shelf, in late Eucene to early Oligocene time in Prydz Bay, possibly in early Miocene time in the Ross Sea, and at least by middle Miocene time in the Weddell Sea. (3) The relative amounts of shelf prograding and inferred ice-volume variations (and related sea-level changes) have increased since middle to late Miocene time in the eastern Ross Sea, Prydz Bay, and possibly Weddell Sea. Our analysis is preliminary. Further acoustic surveys and scientific drilling are needed to resolve the proximal Antarctic record of glacio-eustatic, climatic, and tectonic events recorded by the prograding sequences. ?? 1991.

  5. Pattern of presenting complaints recorded as near-drowning events in emergency departments: a national surveillance study from Pakistan

    PubMed Central

    2015-01-01

    Background Drowning is a heavy burden on the health systems of many countries, including Pakistan. To date, no effective large-scale surveillance has been in place to estimate rates of drowning and near-drowning in Pakistan. The Pakistan National Emergency Department Surveillance (Pak-NEDS) study aimed to fill this gap. Methods Patients who presented with a complaint of "near-drowning" were analyzed to explore patterns of true near-drowning (unintentional) and intentional injuries that led to the "near-drowning" complaint. Bivariate analysis was done to establish patterns among patients treated in emergency departments, including socio-demographic information, injury-related information, accompanying injuries, and emergency department resource utilization. Results A total of 133 patients (0.2% of all injury patients) with "near-drowning" as presenting complaints were recorded by the Pak-NEDS system. True near-drowning (50.0%) and intentional injuries that led to "near-drowning" complaints (50.0%) differed in nature of injuries. The highest proportion of true near-drowning incidents occurred among patients aged between 25-44 years (47.5%), and among males (77.5%). True near-drowning patients usually had other accompanying complaints, such as lower limb injury (40.0%). Very few patients were transported by ambulance (5.0%), and triage was done for 15% of patients. Eleven (27.5%) true near-drowning patients received cardiopulmonary resuscitation. Conclusion There was major under-reporting of drowning and near-drowning cases in the surveillance study. The etiology of near-drowning cases should be further studied. Patients who experienced non-fatal drownings were more commonly sent for medical care due to other accompanying conditions, rather than near-drowning event itself. There is also need for recognizing true near-drowning incidents. The results of this study provide information on data source selection, site location, emergency care standardization, and multi

  6. Records of past mid-depth ventilation: Cretaceous ocean anoxic event 2 vs. Recent oxygen minimum zones

    NASA Astrophysics Data System (ADS)

    Schönfeld, J.; Kuhnt, W.; Erdem, Z.; Flögel, S.; Glock, N.; Aquit, M.; Frank, M.; Holbourn, A.

    2015-02-01

    Present day oceans are well ventilated, with the exception of mid-depth oxygen minimum zones (OMZs) under high surface water productivity, regions of sluggish circulation, and restricted marginal basins. In the Mesozoic, however, entire oceanic basins transiently became dysoxic or anoxic. The Cretaceous ocean anoxic events (OAEs) were characterised by laminated organic-carbon rich shales and low-oxygen indicating trace fossils preserved in the sedimentary record. Yet assessments of the intensity and extent of Cretaceous near-bottom water oxygenation have been hampered by deep or long-term diagenesis and the evolution of marine biota serving as oxygen indicators in today's ocean. Sedimentary features similar to those found in Cretaceous strata were observed in deposits underlying Recent OMZs, where bottom-water oxygen levels, the flux of organic matter, and benthic life have been studied thoroughly. Their implications for constraining past bottom-water oxygenation are addressed in this review. We compared OMZ sediments from the Peruvian upwelling with deposits of the late Cenomanian OAE 2 from the north-west African shelf. Holocene laminated sediments are encountered at bottom-water oxygen levels of < 7 μmol kg-1 under the Peruvian upwelling and < 5 μmol kg-1 in California Borderland basins and the Pakistan Margin. Seasonal to decadal changes of sediment input are necessary to create laminae of different composition. However, bottom currents may shape similar textures that are difficult to discern from primary seasonal laminae. The millimetre-sized trace fossil Chondrites was commonly found in Cretaceous strata and Recent oxygen-depleted environments where its diameter increased with oxygen levels from 5 to 45 μmol kg-1. Chondrites has not been reported in Peruvian sediments but centimetre-sized crab burrows appeared around 10 μmol kg-1, which may indicate a minimum oxygen value for bioturbated Cretaceous strata. Organic carbon accumulation

  7. Uncovering a Salt Giant. Deep-Sea Record of Mediterranean Messinian Events (DREAM) multi-phase drilling project

    NASA Astrophysics Data System (ADS)

    Camerlenghi, Angelo; Aoisi, Vanni; Lofi, Johanna; Hübscher, Christian; deLange, Gert; Flecker, Rachel; Garcia-Castellanos, Daniel; Gorini, Christian; Gvirtzman, Zohar; Krijgsman, Wout; Lugli, Stefano; Makowsky, Yizhaq; Manzi, Vinicio; McGenity, Terry; Panieri, Giuliana; Rabineau, Marina; Roveri, Marco; Sierro, Francisco Javier; Waldmann, Nicolas

    2014-05-01

    In May 2013, the DREAM MagellanPlus Workshop was held in Brisighella (Italy). The initiative builds from recent activities by various research groups to identify potential sites to perform deep-sea scientific drilling in the Mediterranean Sea across the deep Messinian Salinity Crisis (MSC) sedimentary record. In this workshop three generations of scientists were gathered: those who participated in formulation of the deep desiccated model, through DSDP Leg 13 drilling in 1973; those who are actively involved in present-day MSC research; and the next generation (PhD students and young post-docs). The purpose of the workshop was to identify locations for multiple-site drilling (including riser-drilling) in the Mediterranean Sea that would contribute to solve the several open questions still existing about the causes, processes, timing and consequences at local and planetary scale of an outstanding case of natural environmental change in the recent Earth history: the Messinian Salinity Crisis in the Mediterranean Sea. The product of the workshop is the identification of the structure of an experimental design of site characterization, riser-less and riser drilling, sampling, measurements, and down-hole analyses that will be the core for at least one compelling and feasible multiple phase drilling proposal. Particular focus has been given to reviewing seismic site survey data available from different research groups at pan-Mediterranean basin scale, to the assessment of additional site survey activity including 3D seismics, and to ways of establishing firm links with oil and gas industry. The scientific community behind the DREAM initiative is willing to proceed with the submission to IODP of a Multi-phase Drilling Project including several drilling proposals addressing specific drilling objectives, all linked to the driving objectives of the MSC drilling and understanding . A series of critical drilling targets were identified to address the still open questions

  8. A direct comparison of the ages of detrital monazite versus detrital zircon in Appalachian foreland basin sandstones: Searching for the record of Phanerozoic orogenic events

    NASA Astrophysics Data System (ADS)

    Hietpas, Jack; Samson, Scott; Moecher, David

    2011-10-01

    The provenance potential of detrital monazite was investigated by in situ measurement of 232Th- 208Pb dates of grains isolated from six Middle Carboniferous-Permian sandstones from the Appalachian foreland basin. Provenance assessment of these units was previously investigated by measuring U-Pb crystallization ages of detrital zircon (Thomas et al., 2004; Becker et al., 2005, 2006). Approximately 90% of the detrital zircon ages record Mesoproterozoic or older ages, with only 10% recording the three major pulses of tectonism (Taconian, Acadian and Alleghanian) that are the hallmark of the Appalachian Orogen. 232Th- 208Pb ages of detrital monazite, however, strongly record the complex phases of Paleozoic orogenesis. Nearly 65% of the ages record Paleozoic events, while 35% record Neoproterozoic or older ages. In several of the analyzed sandstones, detrital monazite ages record Paleozoic orogenic events that are completely missed by detrital zircon ages, demonstrating that monazite ages more accurately reflect the character of the sediment source rocks. The inferred maximum age of sediment deposition, as determined by the youngest monazite grains, is ~ 550 Ma younger for two of the analyzed sandstones compared to depositional constraints based on the youngest detrital zircon. The different physical properties and petrogenesis of zircon and monazite are interpreted to be factors for the dramatic differences in sediment provenance information provided by each mineral. The results from this study have important implications for determining sediment provenance, constraining maximum age of sediment deposition, and developing robust regional tectonic models.

  9. Stable isotope records of convection variability in the West Pacific Warm Pool from fast-growing stalagmites

    NASA Astrophysics Data System (ADS)

    Maupin, C. R.; Partin, J. W.; Quinn, T. M.; Shen, C.; Lin, K.; Taylor, F. W.; Sinclair, D. J.; Banner, J. L.

    2010-12-01

    The potential response of the tropical Pacific to ongoing anthropogenic global warming conditions is informed by instrumental data, model predictions and climate proxy evidence. However, these distinct lines of evidence lead to opposing predictions in terms of the nature of interannual (ENSO) variability in a warming world. Interpreted in an ENSO framework, warming in the tropical Pacific may elicit a zonally asymmetrical response and lead to an intensified Walker Circulation (more ‘La Niña - like’). Alternatively, discrepancies in the increasing rates of latent heat flux and rainfall due to warming conditions may in fact reduce Walker Circulation (more ‘El Niño - like’). However, in order for such a framework to be useful in the context of future climate change, some knowledge of the natural variability in the strength of Walker Circulation components is required. The extant instrumental data are not of sufficient temporal length to fully assess the spectrum of natural variability in such climate components. Oxygen isotope records from tropical speleothems have been successfully used to document the nature of precessional forcing on precipitation and atmospheric circulation patterns throughout the tropics. Typical stalagmite growth rates of 10-100 μm yr-1 allow decadally resolved records of δ18O variability on time scales of centuries to millennia and beyond. Here we present the initial results from calcite stalagmites of heretofore unprecedented growth rates (~1-4 mm yr-1) in a cave in northwest Guadalcanal, Solomon Islands (~9°S, 160°E). These stalagmites have been absolutely dated by U-Th techniques and indicate stalagmite growth spanning ~1650 to 2010 CE. The δ18O records from stalagmites provide evidence for changes in convection in the equatorial WPWP region of the SPCZ: the rising limb of the Pacific Walker Circulation, and therefore provide critical insight into changes in zonal atmospheric circulation across the Pacific.

  10. Patient-Reported Safety Events in Chronic Kidney Disease Recorded With an Interactive Voice-Inquiry Dial-Response System: Monthly Report Analysis

    PubMed Central

    Doerfler, Rebecca M; Yoffe, Marni R; Diamantidis, Clarissa J; Blumenthal, Jacob B; Siddiqui, Tariq; Gardner, James F; Snitker, Soren; Zhan, Min

    2016-01-01

    Background Monitoring patient-reported outcomes (PROs) may improve safety of chronic kidney disease (CKD) patients. Objective Evaluate the performance of an interactive voice-inquiry dial-response system (IVRDS) in detecting CKD-pertinent adverse safety events outside of the clinical environment and compare the incidence of events using the IVDRS to that detected by paper diary. Methods This was a 6-month study of Stage III-V CKD patients in the Safe Kidney Care (SKC) study. Participants crossed over from a paper diary to the IVDRS for recording patient-reported safety events defined as symptoms or events attributable to medications or care. The IVDRS was adapted from the SKC paper diary to record event frequency and remediation. Participants were auto-called weekly and permitted to self-initiate calls. Monthly reports were reviewed by two physician adjudicators for their clinical significance. Results 52 participants were followed over a total of 1384 weeks. 28 out of 52 participants (54%) reported events using the IVDRS versus 8 out of 52 (15%) with the paper diary; hypoglycemia was the most common event for both methods. All IVDRS menu options were selected at least once except for confusion and rash. Events were reported on 121 calls, with 8 calls reporting event remediation by ambulance or emergency room (ER) visit. The event rate with the IVDRS and paper diary, with and without hypoglycemia, was 26.7 versus 4.7 and 18.3 versus 0.8 per 100 person weeks, respectively (P=.002 and P<.001). The frequent users (ie, >10 events) largely differed by method, and event rates excluding the most frequent user of each were 16.9 versus 2.5 per 100 person weeks, respectively (P<.001). Adjudicators found approximately half the 80 reports clinically significant, with about a quarter judged as actionable. Hypoglycemia was often associated with additional reports of fatigue and falling. Participants expressed favorable satisfaction with the IVDRS. Conclusions Use of the IVDRS

  11. Identification of paleo-events recorded in the yellow sea sediments by sorting coefficient of grain size.

    PubMed

    Sun, Liguang; Zhou, Xin; Wang, Yuhong; Cheng, Wenhan; Jia, Nan

    2012-01-01

    Identification of natural and anthropogenic events in the past is important for studying their patterns and mechanisms; and sensitive proxies in marine sediments are more reliable for identifying these events than those in terrestrial sediments, which are usually disturbed by human activities. Since the main source materials for the sediments in the Northern Yellow Sea Mud are transported by the Yellow River, sedimentary characteristics can be used to reconstruct the historical events that occurred in the Yellow River Valley. In the present study, by analyzing sorting coefficient of grain size in a 250-year sediment core from the Northern Yellow Sea Mud, we identified several major historical events: the Haiyuan Earthquake in AD 1920 and several times of relocation of the Yellow River estuary. The proxy has the potential of detecting and reconstructing historical events; in combination with historical archives, they also provide an accurate dating method.

  12. Strong fast long-period waves in the Efpalio 2010 earthquake records: explanation in terms of leaking modes

    NASA Astrophysics Data System (ADS)

    Vackář, Jiří; Zahradník, Jiří; Sokos, Efthimios

    2014-01-01

    The January 18, 2010, shallow earthquake in the Corinth Gulf, Greece ( M w 5.3) generated unusually strong long-period waves (periods 4-8 s) between the P and S wave arrival. These periods, being significantly longer than the source duration, indicated a structural effect. The waves were observed in epicentral distances 40-250 km and were significant on radial and vertical component. None of existing velocity models of the studied region provided explanation of the waves. By inverting complete waveforms, we obtained an 1-D crustal model explaining the observation. The most significant feature of the best-fitting model (as well as the whole suite of models almost equally well fitting the waveforms) is a strong velocity step at depth about 4 km. In the obtained velocity model, the fast long-period wave was modeled by modal summation and identified as a superposition of several leaking modes. In this sense, the wave is qualitatively similar to P long or Pnl waves, which however are usually reported in larger epicentral distances. The main innovation of this paper is emphasis to smaller epicentral distances. We studied properties of the wave using synthetic seismograms. The wave has a normal dispersion. Azimuthal and distance dependence of the wave partially explains its presence at 46 stations of 70 examined. Depth dependence shows that the studied earthquake was very efficient in the excitation of these waves just due to its shallow centroid depth (4.5 km).

  13. Recovering Paleo-Records from Antarctic Ice-Cores by Coupling a Continuous Melting Device and Fast Ion Chromatography.

    PubMed

    Severi, Mirko; Becagli, Silvia; Traversi, Rita; Udisti, Roberto

    2015-11-17

    Recently, the increasing interest in the understanding of global climatic changes and on natural processes related to climate yielded the development and improvement of new analytical methods for the analysis of environmental samples. The determination of trace chemical species is a useful tool in paleoclimatology, and the techniques for the analysis of ice cores have evolved during the past few years from laborious measurements on discrete samples to continuous techniques allowing higher temporal resolution, higher sensitivity and, above all, higher throughput. Two fast ion chromatographic (FIC) methods are presented. The first method was able to measure Cl(-), NO3(-) and SO4(2-) in a melter-based continuous flow system separating the three analytes in just 1 min. The second method (called Ultra-FIC) was able to perform a single chromatographic analysis in just 30 s and the resulting sampling resolution was 1.0 cm with a typical melting rate of 4.0 cm min(-1). Both methods combine the accuracy, precision, and low detection limits of ion chromatography with the enhanced speed and high depth resolution of continuous melting systems. Both methods have been tested and validated with the analysis of several hundred meters of different ice cores. In particular, the Ultra-FIC method was used to reconstruct the high-resolution SO4(2-) profile of the last 10,000 years for the EDML ice core, allowing the counting of the annual layers, which represents a key point in dating these kind of natural archives.

  14. Automated detection of feeding strikes by larval fish using continuous high-speed digital video: a novel method to extract quantitative data from fast, sparse kinematic events.

    PubMed

    Shamur, Eyal; Zilka, Miri; Hassner, Tal; China, Victor; Liberzon, Alex; Holzman, Roi

    2016-06-01

    Using videography to extract quantitative data on animal movement and kinematics constitutes a major tool in biomechanics and behavioral ecology. Advanced recording technologies now enable acquisition of long video sequences encompassing sparse and unpredictable events. Although such events may be ecologically important, analysis of sparse data can be extremely time-consuming and potentially biased; data quality is often strongly dependent on the training level of the observer and subject to contamination by observer-dependent biases. These constraints often limit our ability to study animal performance and fitness. Using long videos of foraging fish larvae, we provide a framework for the automated detection of prey acquisition strikes, a behavior that is infrequent yet critical for larval survival. We compared the performance of four video descriptors and their combinations against manually identified feeding events. For our data, the best single descriptor provided a classification accuracy of 77-95% and detection accuracy of 88-98%, depending on fish species and size. Using a combination of descriptors improved the accuracy of classification by ∼2%, but did not improve detection accuracy. Our results indicate that the effort required by an expert to manually label videos can be greatly reduced to examining only the potential feeding detections in order to filter false detections. Thus, using automated descriptors reduces the amount of manual work needed to identify events of interest from weeks to hours, enabling the assembly of an unbiased large dataset of ecologically relevant behaviors.

  15. A 1-Ma record of sea surface temperature and extreme cooling events in the North Atlantic: A perspective from the Iberian Margin

    NASA Astrophysics Data System (ADS)

    Rodrigues, T.; Alonso-García, M.; Hodell, D. A.; Rufino, M.; Naughton, F.; Grimalt, J. O.; Voelker, A. H. L.; Abrantes, F.

    2017-09-01

    The Iberian Margin is a sensitive area to track high and low latitude processes, and is a key location to understand major past climatic and oceanographic changes. Here we present new biomarker data from IODP Site U1385 (;Shackleton site;) (1017-336 ka) that, when combined with existing data from Cores MD01-2443/4 (last 335 ka), allows us to assess the evolution of sea surface temperature (SST) and meltwater influx over the last 1 Ma at the Iberian Margin. Interglacial periods throughout the last 1 Ma show SST close to 20 °C, even during the so-called ;luke-warm; interglacials that are marked by relatively low atmospheric CO2 concentrations. During glacial periods, extremely cold stadial events are recognized at the Iberian Margin, and are very likely related to meltwater discharges from the European and British-Irish ice sheets into the NE Atlantic, which were transported southwards by the Portugal Current. We subdivided the record into four intervals on the basis of the timing and the magnitude of these extremely cold stadials: 1) from 1017 to ∼900 ka, only minor sporadic freshwater input occurred during deglaciations; 2) from 900 to 675 ka extreme cold events occur as terminal stadial events at the beginning of the deglaciations, which results in abrupt deglacial SST shifts; 3) from 675 to 450 ka only a few, very short-lived events are recorded and seldom is there freshwater input at the Iberian Margin; 4) during the last 450 ka the extreme cold events occurred under full glacial conditions, with particularly severe events during MIS 6 and 8. We propose these mid -glacial events are associated with a strong discharges of European ice sheet (EIS). The fact that these extreme cold events do not coincide with deglaciations questions the role of European ice sheet discharges in triggering deglaciations.

  16. Full moment tensor inversion of mining induced seismic events recorded at the Legnica-Glogow Underground Mining Induced Earthquale Observing System (LUMINEOS), Poland

    NASA Astrophysics Data System (ADS)

    Rudzinski, Lukasz; Cesca, Simone; Lizurek, Grzegorz

    2014-05-01

    Since January 2013 a new surface seismic network LUMINEOS (Legnica-Glogow Underground Mining INduced Earthquake Observing System) is in operation to monitor induced seismicity around the mining district of Legnica Glogow Copper District (LGCP), Poland. The network belongs to the Institute of Geophysics of the Polish Academy of Sciences. The network is located above the deep copper mine "Rudna". It consists of nine three-axis short period seismometers and continuously records seismic events connected with intensive copper ore excavation at close by mines. In parallel, the mining company operates an in-mine underground seismic network, consisting of 32 short period vertical sensors. During 2013 several strong induced seismic events with M > 2.5 were recorded on both networks. The collected data set provides an opportunity to analyze their focal mechanisms. In this work we present the first results of full moment tensor inversion for mining induced seismic events, using both recording systems. LUMINEOS results were obtained with waveforms inversion using the Kiwi tool package (http://kinherd.org), while for the in-mine network, we used a first amplitude P-wave inversions. Our results suggest that both systems can be used complementary in cases of strong mining events, providing a well constrained focal mechanism and information on the rupture processes in the mine.

  17. Fast events and waves in an active region of the Sun observed in Hα with high spatial resolution

    NASA Astrophysics Data System (ADS)

    Sánchez-Andrade Nuño, B.; Bello González, N.; Blanco Rodríguez, J.; Kneer, F.; Puschmann, K. G.

    2008-08-01

    Context: We study the chromosphere of an active region of the Sun in the Hα line. Aims: The development of new instrumentation and new methods of data analysis allows to scrutinize the dynamics of the solar chromosphere with high spatial, spectral, and temporal resolution. The observations we present shed light on some magneto-dynamic processes occurring above an active region in the chromosphere. Methods: We took a time series of 55 min in Hα from AR 10875 at θ≈36°. We used the “Göttingen” Fabry-Perot spectrometer at the Vacuum Tower Telescope, Observatorio del Teide/Tenerife, to obtain two-dimensional spectrograms in Hα. Adaptive optics and image reconstruction yielded a spatial resolution better than 0.5 arcsec throughout the time sequence. From the wealth of structures, we selected areas of interest to study further, in detail, some ongoing processes. Results: A small straight surge developed aside of a pore with upward phase speed of 100 km s-1 and line-of-sight (LOS) velocity of 15 km s-1. The surge retreated rapidly with LOS velocity of 45 km s-1 at its mouth. It underwent a rebound and fell back again. Two sympathetic mini-flares were observed that lasted only approximately 40 s, but showed strong Hα emission. We found magnetoacoustic waves in long fibrils as mainly short wave trains, short packets or pulses, i.e., solitary waves consisting of small (1´´-2´´) blobs. They start at either end of the fibrils and travel with phase speeds of 12-14 km s-1, i.e., close to the tube speed and approximately the sound velocity for sufficiently large magnetic field strengths. Some waves speed up to reach velocities of the order of 30 km s-1. This is much lower than the expected Alfvén velocity of ≥200 km s-1 for reasonable magnetic field strengths and mass densities. We suggest that slow waves are not purely longitudinal, but possess gas velocities perpendicular to the direction of propagation of few km s-1. Also, fast waves travel along sinuous

  18. Evidence for higher-than-average air temperatures after the 8.2 ka event provided by a Central European δ18O record

    NASA Astrophysics Data System (ADS)

    Andersen, Nils; Lauterbach, Stefan; Erlenkeuser, Helmut; Danielopol, Dan L.; Namiotko, Tadeusz; Hüls, Matthias; Belmecheri, Soumaya; Dulski, Peter; Nantke, Carla; Meyer, Hanno; Chapligin, Bernhard; von Grafenstein, Ulrich; Brauer, Achim

    2017-09-01

    The so-called 8.2 ka event represents one of the most prominent cold climate anomalies during the Holocene warm period. Accordingly, several studies have addressed its trigger mechanisms, absolute dating and regional characteristics so far. However, knowledge about subsequent climate recovery is still limited although this might be essential for the understanding of rapid climatic changes. Here we present a new sub-decadally resolved and precisely dated oxygen isotope (δ18O) record for the interval between 7.7 and 8.7 ka BP (103 calendar years before AD 1950), derived from the calcareous valves of benthic ostracods preserved in the varved lake sediments of pre-Alpine Mondsee (Austria). Besides a clear reflection of the 8.2 ka event, showing a good agreement in timing, duration and magnitude with other regional stable isotope records, the high-resolution Mondsee lake sediment record provides evidence for a 75-year-long interval of higher-than-average δ18O values directly after the 8.2 ka event, possibly reflecting increased air temperatures in Central Europe. This observation is consistent with evidence from other proxy records in the North Atlantic realm, thus most probably reflecting a hemispheric-scale climate signal rather than a local phenomenon. As a possible trigger we suggest an enhanced resumption of the Atlantic meridional overturning circulation (AMOC), supporting assumptions from climate model simulations.

  19. Fast joint detection-estimation of evoked brain activity in event-related FMRI using a variational approach.

    PubMed

    Chaari, Lotfi; Vincent, Thomas; Forbes, Florence; Dojat, Michel; Ciuciu, Philippe

    2013-05-01

    In standard within-subject analyses of event-related functional magnetic resonance imaging (fMRI) data, two steps are usually performed separately: detection of brain activity and estimation of the hemodynamic response. Because these two steps are inherently linked, we adopt the so-called region-based joint detection-estimation (JDE) framework that addresses this joint issue using a multivariate inference for detection and estimation. JDE is built by making use of a regional bilinear generative model of the BOLD response and constraining the parameter estimation by physiological priors using temporal and spatial information in a Markovian model. In contrast to previous works that use Markov Chain Monte Carlo (MCMC) techniques to sample the resulting intractable posterior distribution, we recast the JDE into a missing data framework and derive a variational expectation-maximization (VEM) algorithm for its inference. A variational approximation is used to approximate the Markovian model in the unsupervised spatially adaptive JDE inference, which allows automatic fine-tuning of spatial regularization parameters. It provides a new algorithm that exhibits interesting properties in terms of estimation error and computational cost compared to the previously used MCMC-based approach. Experiments on artificial and real data show that VEM-JDE is robust to model misspecification and provides computational gain while maintaining good performance in terms of activation detection and hemodynamic shape recovery.

  20. Fast joint detection-estimation of evoked brain activity in event-related FMRI using a variational approach

    PubMed Central

    Chaari, Lotfi; Vincent, Thomas; Forbes, Florence; Dojat, Michel; Ciuciu, Philippe

    2013-01-01

    In standard within-subject analyses of event-related fMRI data, two steps are usually performed separately: detection of brain activity and estimation of the hemodynamic response. Because these two steps are inherently linked, we adopt the so-called region-based Joint Detection-Estimation (JDE) framework that addresses this joint issue using a multivariate inference for detection and estimation. JDE is built by making use of a regional bilinear generative model of the BOLD response and constraining the parameter estimation by physiological priors using temporal and spatial information in a Markovian model. In contrast to previous works that use Markov Chain Monte Carlo (MCMC) techniques to sample the resulting intractable posterior distribution, we recast the JDE into a missing data framework and derive a Variational Expectation-Maximization (VEM) algorithm for its inference. A variational approximation is used to approximate the Markovian model in the unsupervised spatially adaptive JDE inference, which allows automatic fine-tuning of spatial regularization parameters. It provides a new algorithm that exhibits interesting properties in terms of estimation error and computational cost compared to the previously used MCMC-based approach. Experiments on artificial and real data show that VEM-JDE is robust to model mis-specification and provides computational gain while maintaining good performance in terms of activation detection and hemodynamic shape recovery. PMID:23096056

  1. A System for Reflective Learning Using Handwriting Tablet Devices for Real-Time Event Bookmarking into Simultaneously Recorded Videos

    ERIC Educational Resources Information Center

    Nakajima, Taira

    2012-01-01

    The author demonstrates a new system useful for reflective learning. Our new system offers an environment that one can use handwriting tablet devices to bookmark symbolic and descriptive feedbacks into simultaneously recorded videos in the environment. If one uses video recording and feedback check sheets in reflective learning sessions, one can…

  2. A System for Reflective Learning Using Handwriting Tablet Devices for Real-Time Event Bookmarking into Simultaneously Recorded Videos

    ERIC Educational Resources Information Center

    Nakajima, Taira

    2012-01-01

    The author demonstrates a new system useful for reflective learning. Our new system offers an environment that one can use handwriting tablet devices to bookmark symbolic and descriptive feedbacks into simultaneously recorded videos in the environment. If one uses video recording and feedback check sheets in reflective learning sessions, one can…

  3. From flood-event to climate in an alpine context (Arve valley, France): methodological issues toward the confrontation of historical documentation and geological records

    NASA Astrophysics Data System (ADS)

    Mélo, Alain; Ployon, Estelle; Wilhelm, Bruno; Arnaud, Fabien

    2014-05-01

    various flood types. We were hence able to distinguish different types of flood events from localised thunderstorms, generalised thunderstorm activity in uppermost catchment areas toward generalised heavy precipitation affecting the whole river Arve Catchment area (~ 2500 km²).We hence point the diversity of meteorological situations susceptible to lead to the recording of flood events. In order to properly confront historical documents- and geological archives-based flood chronicles this diversity must thus be taken into account. In that aim, using time geography-based representations may help in attributing a given record to a given meteorological context.

  4. Detection and Magnetic Source Imaging of Fast Oscillations (40-160 Hz) Recorded with Magnetoencephalography in Focal Epilepsy Patients.

    PubMed

    von Ellenrieder, Nicolás; Pellegrino, Giovanni; Hedrich, Tanguy; Gotman, Jean; Lina, Jean-Marc; Grova, Christophe; Kobayashi, Eliane

    2016-03-01

    We present a framework to detect fast oscillations (FOs) in magnetoencephalography (MEG) and to perform magnetic source imaging (MSI) to determine the location and extent of their generators in the cortex. FOs can be of physiologic origin associated to sensory processing and memory consolidation. In epilepsy, FOs are of pathologic origin and biomarkers of the epileptogenic zone. Seventeen patients with focal epilepsy previously confirmed with identified FOs in scalp electroencephalography (EEG) were evaluated. To handle data deriving from large number of sensors (275 axial gradiometers) we used an automatic detector with high sensitivity. False positives were discarded by two human experts. MSI of the FOs was performed with the wavelet based maximum entropy on the mean method. We found FOs in 11/17 patients, in only one patient the channel with highest FO rate was not concordant with the epileptogenic region and might correspond to physiologic oscillations. MEG FOs rates were very low: 0.02-4.55 per minute. Compared to scalp EEG, detection sensitivity was lower, but the specificity higher in MEG. MSI of FOs showed concordance or partial concordance with proven generators of seizures and epileptiform activity in 10/11 patients. We have validated the proposed framework for the non-invasive study of FOs with MEG. The excellent overall concordance with other clinical gold standard evaluation tools indicates that MEG FOs can provide relevant information to guide implantation for intracranial EEG pre-surgical evaluation and for surgical treatment, and demonstrates the important added value of choosing appropriate FOs detection and source localization methods.

  5. An account of a flare related shock event recorded by the energetic particle detector EPONA of the Giotto spacecraft during September 1985 (STIP interval 18)

    NASA Technical Reports Server (NTRS)

    Mckennalawlor, Susan M. P.; Kirsch, E.; Daly, P.; Osullivan, D.; Thompson, A.; Wenzel, P-K

    1987-01-01

    The Energetic Particle Detector EPONA flown on the Giotto Mission to Halley's Comet was designed to measure electrons, protons, and heavier ions (E greater that 20 keV) in the Comet Halley environment and during the Cruise Phase of the mission (EPONA switch on: 22 August 1985 - Halley encounter: 13 March 1986). In September 1985 (STIP Interval XVIII) a well defined shock event was recorded at EPONA in association with a sequence of solar flares and a preliminary account of this event is presented.

  6. Surge Driven Return Flow Results in Deposition of Coarse Grain Horizons Archiving a 4000 Year Record of Extreme Storm Events, Cape Cod, Massachusetts

    NASA Astrophysics Data System (ADS)

    Maio, C. V.; Donnelly, J. P.; Sullivan, R.; Weidman, C. R.; Sheremet, V.

    2014-12-01

    The brevity of the instrumental record and lack of detailed historical accounts is a limiting factor in our understanding of the relationship between climate change and the frequency and intensity of extreme storm events. This study applied paleotempestologic and hydrographic methods to identify the mechanisms of storm-induced coarse grain deposition and reconstruct a late Holocene storm record within Waquoit Bay, Massachusetts. Three sediment cores (6.0 m, 8.4 m, and 8.2 m) were collected in 3 m of water using a vibracore system. Grain sizes were measured along core to identify coarse grain anomalies that serve as a proxy for past storm events. An historical age model (1620-2011 AD) was developed based on Pb pollution chronomarkers derived from X-Ray Florescence bulk Pb data, equating to a sedimentation rate of 8-8.3 mm/yr (R2 = 0.99). A long-term (4000 to 275 years before present) sedimentation rate of 1.1-1.4 mm/yr (R2 = 0.89) was calculated based on twenty-four continuous flow atomic mass spectrometry 14C ages of marine bivalves. To determine hydrographic conditions within the embayment during storm events current meters and tide gauges were deployed during Hurricane Irene (2011) which measured a storm surge of 88 cm above mean sea level. The buildup of storm water against the landward shoreline resulted in a measured 10 cm/s seaward moving bottom current capable of transporting coarse sand eroded from the adjacent shoreface into the coring site. Modeled surges for eleven modern and historic storm events ranged in height from 0.37 m (2011) to 3.72 m (1635) above mean high water. The WAQ1, WAQ2, and WAQ3 cores recorded a total of 89, 139, and 137 positive anomalies that exceeded the lower threshold and 15, 34, and 12 that exceeded the upper threshold respectively. Events recorded during the historic period coincide with documented storm events. The mean frequency within the three cores applying the lower threshold was 2.6 events per century, while applying the

  7. Coral-based climate records from tropical South Atlantic: 2009/2010 ENSO event in C and O isotopes from Porites corals (Rocas Atoll, Brazil).

    PubMed

    Pereira, Natan S; Sial, Alcídes N; Kikuchi, Ruy K P; Ferreira, Valderez P; Ullmann, Clemens V; Frei, Robert; Cunha, Adriana M C

    2015-01-01

    Coral skeletons contain records of past environmental conditions due to their long life span and well calibrated geochemical signatures. C and O isotope records of corals are especially interesting, because they can highlight multidecadal variability of local climate conditions beyond the instrumental record, with high fidelity and sub-annual resolution. Although, in order to get an optimal geochemical signal in coral skeleton, sampling strategies must be followed. Here we report one of the first coral-based isotopic record from the Equatorial South Atlantic from two colonies of Porites astreoides from the Rocas Atoll (offshore Brazil), a new location for climate reconstruction. We present time series of isotopic variation from profiles along the corallite valley of one colony and the apex of the corallite fan of the other colony. Significant differences in the isotopic values between the two colonies are observed, yet both record the 2009/2010 El Niño event - a period of widespread coral bleaching - as anomalously negative δ18O values (up to -1 permil). δ13C is found to be measurably affected by the El Niño event in one colony, by more positive values (+0.39 ‰), and together with a bloom of endolithic algae, may indicate physiological alteration of this colony. Our findings indicate that corals from the Rocas Atoll can be used for monitoring climate oscillations in the tropical South Atlantic Ocean.

  8. MoonRise: Sampling South Pole-Aitken Basin as a Recorder of Solar System Events (Invited)

    NASA Astrophysics Data System (ADS)

    Jolliff, B. L.; Shearer, C., Jr.; Gaddis, L. R.; Pieters, C. M.; Head, J. W.; Haruyama, J.; Jaumann, R.; Ohtake, M.; Osinski, G.; Papanastassiou, D. A.; Petro, N. E.; Moonrise Science Team

    2010-12-01

    The MoonRise mission, now in a phase A concept study, would launch in 2016 and return samples from the Moon’s South Pole-Aitken basin (SPA) in 2017. These samples would be used to (1) determine the chronology of SPA and test the “cataclysm” hypothesis for bombardment of the inner Solar System some hundreds of millions of years following planetary accretion, (2) investigate the deep crust and upper mantle of the Moon to better understand planetary differentiation, and (3) provide ground truth for orbital remote sensing and geophysics of the SPA basin to better understand giant basin-forming impact processes and the effects of such impacts on an early-formed planetary crust. The key objective that drives site selection for the MoonRise mission is to obtain rock samples that crystallized from the SPA impact-melt complex to date the formation of the basin. Many large impacts, however, occurred subsequent to SPA formation, and volcanic lavas erupted into the interior of SPA over several hundred million years, producing a complex set of geologic formations. Fortunately, the very same impact process also generates a rich diversity of rock types in the regolith that provide a record of all these events. Our focus for landing site selection is in the interior of SPA where the distinctive geochemical signature is strongest. This compositional signature, coupled with modeling of impact ejecta ballistic sedimentation and distribution, ensures that landing sites and sampling locations in the interior of SPA will contain abundant rock fragments derived from the original SPA melt sheet. The wealth of recent remote sensing data provides context to evaluate geologic formations and to establish provenance for the samples. Admixture of impactites derived from younger basins such as Apollo, Poincaré, Planck, Ingenii, Orientale and Schrödinger, as well as other large impact craters, will contribute to a chronology that is bounded by the earliest and the latest of the recognized

  9. Year-long continuous personal exposure to PM 2.5 recorded by a fast responding portable nephelometer

    NASA Astrophysics Data System (ADS)

    Braniš, Martin; Kolomazníková, Jana

    2010-08-01

    Personal exposure to particulate matter of aerodynamic diameter under 2.5 μm (PM 2.5) was monitored using a DustTrak nephelometer. The battery-operated unit, worn by an adult individual for a period of approximately one year, logged integrated average PM 2.5 concentrations over 5 min intervals. A detailed time-activity diary was used to record the experimental subject's movement and the microenvironments visited. Altogether 239 days covering all the months (except April) were available for the analysis. In total, 60 463 acceptable 5-min averages were obtained. The dataset was divided into 7 indoor and 4 outdoor microenvironments. Of the total time, 84% was spent indoors, 10.9% outdoors and 5.1% in transport. The indoor 5-min PM 2.5 average was higher (55.7 μg m -3) than the outdoor value (49.8 μg m -3). The highest 5-min PM 2.5 average concentration was detected in restaurant microenvironments (1103 μg m -3), the second highest 5-min average concentration was recorded in indoor spaces heated by stoves burning solid fuels (420 μg m -3). The lowest 5-min mean aerosol concentrations were detected outdoors in rural/natural environments (25 μg m -3) and indoors at the monitored person's home (36 μg m -3). Outdoor and indoor concentrations of PM 2.5 measured by the nephelometer at home and during movement in the vicinity of the experimental subject's home were compared with those of the nearest fixed-site monitor of the national air quality monitoring network. The high correlation coefficient (0.78) between the personal and fixed-site monitor aerosol concentrations suggested that fixed-site monitor data can be used as proxies for personal exposure in residential and some other microenvironments. Collocated measurements with a reference method (β-attenuation) showed a non-linear systematic bias of the light-scattering method, limiting the use of direct concentration readings for exact exposure analysis.

  10. Searching for events in Chinese ancient records to explain the increase in 14C from AD 774-775 and AD 993-994

    NASA Astrophysics Data System (ADS)

    Chai, Ya-Ting; Zou, Yuan-Chuan

    2015-09-01

    According to analysis of the 14C content in two Japanese trees, that grew over a period of approximately 3000 years, with high time resolution, Miyake et al. found a rapid increase at AD 774-775 and another one at AD 993-994. These increases correspond to high-energy events that happened within those years and radiated γ-ray energy of about 7×1024 erg toward the Earth. The origin of these events is a mystery. Such strong events should have an unusual optical counterpart, and have been recorded in historical literatures. We searched Chinese historical materials around AD 744-775 and AD 993-994, but no remarkable event was found except for a violent thunderstorm in AD 775. However, the possibility of a thunderstorm containing so much energy is unlikely. We conclude that the events, which caused the 14C increase, are still unclear. These events most probably had no optical counterpart, and a short gamma-ray burst, giant flare of a soft gamma-ray repeater or a terrestrial γ-ray flash could all be candidates.

  11. A High-Resolution Labrador Sea Surface and Subsurface Water Foraminiferal δ18O Record and its Relation to Heinrich Events.

    NASA Astrophysics Data System (ADS)

    Brown, Z. E.; Hoffman, J. S.; Clark, P. U.

    2015-12-01

    Heinrich events are characterized by episodic iceberg discharge events from the Laurentide ice sheet via the Hudson Strait Ice Stream (HSIS) and into the North Atlantic. Although their occurrence throughout late Pleistocene glaciations has been well documented in the oceanic sediment record, the triggering mechanism for Heinrich events is still poorly understood. Recent work (Marcott et al., 2011) has shown that subsurface ocean (~1200 m) warming in response to a shutdown of the Atlantic Meridional Overturning Circulation (AMOC) could lead to accelerated melting and destabilization of an ice shelf fronting the Laurentide Ice Sheet and subsequently trigger Heinrich events. However, evidence for this subsurface warming remains restricted to one core site. Here we use Labrador Sea cores HU2001043-008pc/twc and HU2006040-006pc from the Flemish Cap and Hamilton Spur, respectively, to assess spatial and depth coverage of this signal. We infer surface and subsurface temperature variability using δ18O in benthic and planktic foraminifera. We also develop a corresponding suite of other sediment core proxies in order to identify Heinrich layers, including X-Ray Fluorescence, Ca/Sr, and % dolomite/calcite data. This research will allow us to evaluate changes in the thermodynamic structure of the Labrador basin due to changes in the strength of the AMOC and their relation to Heinrich events. Results will be used to substantiate existing research and coupled ocean-atmospheric models that suggest a reduced AMOC and associated subsurface warming as the trigger for Heinrich events.

  12. Combined palaeomagnetic secular variation and petrophysical records to time-constrain geological and hazardous events: An example from the eastern Tyrrhenian Sea over the last 120 ka

    NASA Astrophysics Data System (ADS)

    Iorio, Marina; Liddicoat, Joseph; Budillon, Francesca; Incoronato, Alberto; Coe, Robert S.; Insinga, Donatella D.; Cassata, William S.; Lubritto, Carmine; Angelino, Antimo; Tamburrino, Stella

    2014-02-01

    Long-term change of Earth's magnetic field (palaeomagnetic secular variation, PSV) during much of the last approximately 120 ka was recorded in cored sediment from the slope margin of the eastern Tyrrhenian Sea. The PSV record has been correlated to master curves of global palaeomagnetic field intensity and PSV records for western Europe. Tephrochronology and radiometric dating (14C and 40Ar/39Ar) have also been used to constrain the age of the PSV record. The combination of the new data with prior PSV and petrophysical data from the area provides a chronological framework for geological events such as large-scale submarine slumps, stratigraphic gaps and short-term changes in deposition rate on the continental margin. These latter changes are linked to the combined action of relative sea-level oscillations, climate events, and consequent variations in land exposure through time. Moreover, new data concerning the thickness and dispersal of Campanian Plain pyroclastic deposits in the marine setting enable volcanic-hazard evaluation. Finally, a pyroclastic deposit (tephra X-6) found offshore in the Southern Campanian marine environment was 40Ar/39Ar dated for the first time at 108.9 ± 1.8 ka BP.

  13. Comparison of hypocenters and their uncertainties determined by three location methods: A case study on hydro-fracturing microseismic events recorded at a dense sub-surface array

    NASA Astrophysics Data System (ADS)

    Woo, J. U.; Rhie, J.; Kim, J. H.

    2015-12-01

    The hypocenters of microseismic events induced by hydro-fracturing for developing shale gas provide important information on the characteristics of the fracture networks. This information is crucial to evaluate the production rate and also make a plan for efficient hydro-fracturing design. Therefore, the accurate hypocenter determination of microseismic events is very important from the economic point of view and the tolerable location error should be only dozens of meters for this purpose. In this study, we test three methods, which are widely used for locating earthquakes in seismology, to determine the hypocenters of microseismic events generated during the commercial shale gas development and recorded at a dense sub-surface array. We selected 1-hour time window and applied automatic picking algorithm to identify events and measure P and S arrival times of them. Our automatic picking algorithm identified 84 events in given time window and 73 of them are reliably located by all three methods. The first method is based on linear and iterative inversion and locates individual events separately. The second method simultaneously locates clustered events and reduces location errors due to incorrect velocity model by introducing the station terms. The third method locates only relative rather than absolute locations of clustered events using double difference algorithm. 1D P and S-wave velocity models are constructed based on well-logging data. Automatically measured P and S arrival times are used for determining absolute locations and relative arrival times measured by waveform cross-correlation are utilized for relative locations. Our preliminary result indicates that double difference method combined with waveform cross-correlations is more applicable than other two methods in that it satisfies the required accuracy for the microseismic monitoring.

  14. The phasing of atmospheric and environmental response to Dansgaard-Oeschger events from highly resolved multi-component Greenland aerosol records

    NASA Astrophysics Data System (ADS)

    Erhardt, Tobias; Capron, Emelie; Olander Rasmussen, Sune; Schüpbach, Simon; Bigler, Matthias; Fischer, Hubertus

    2017-04-01

    During the last glacial period a series of millennial scale rapid warming events with subsequent cooling is well documented in the proxy record throughout the Northern Hemisphere (NH). It is widely assumed that these so called Dansgaard-Oeschger (DO) events are linked to an increase in the Atlantic Meridional Overturning Circulation (AMOC), which leads to warming of the Northern Hemisphere and a cooling of the Southern Hemisphere. Furthermore changes in the atmospheric circulation such as shifts in the Inter Tropical Convergence Zone (ITCZ) and the westerlies. However, the trigger, detailed mechanisms and progress of these events are still not completely understood. Here we present annually to multi-annually resolved multi-component aerosol records from both the NGRIP and NEEM ice cores from Greenland spanning the last glacial period and the early Holocene. Using a probabilistic approach, we investigate the relative timing of the warming onsets and terminations of the different aerosol species and the respective lengths of the transitions and warm events in the different aerosols, where different aerosol species reflect different circulation patterns and geographical distinct source regions. Within uncertainties, we do not find any systematic differences in either the timing or the lengths of the warming transitions between the investigated aerosol species. Because ice core aerosol records are a result of emission, transport and deposition processes, their variability can be interpreted in terms of changing atmospheric circulation influencing the transport, changing precipitation rate influencing deposition of aerosol en route as well as changes in source processes. We try to separate these effects and discuss these results with regard to possible changes in the position of the ITZC and moisture availability over the North Atlantic.

  15. A 50,000-year record of climate oscillations from Florida and its temporal correlation with the Heinrich events

    SciTech Connect

    Grimm, E.C. ); Jacobson, G.L. Jr.; Maasch, K.A. ); Watts, W.A. ); Hansen, B.C.S. )

    1993-07-09

    Oscillations of Pinus (pine) pollen in a 50,000-year sequence from Lake Tulane, Florida, indicate that there were major vegetation shifts during the last glacial cycle. Episodes of abundant Pinus populations indicate a climate that was more wet than intervening phases dominated by Quercus (oak) and Ambrosia-type (ragweed and marsh-elder). The Pinus episodes seem to be temporally correlated with the North Atlantic Heinrich events, which were massive, periodic advances of ice streams from the eastern margin of the Laurentide Ice Sheet. Possible links between the Tulane Pinus and Heinrich events include hemispheric cooling, the influences of Mississippi meltwater on sea-surface temperatures in the Gulf of Mexico, and the effects of North Atlantic thermohaline circulation on currents in the Gulf. 33 refs., 4 figs., 1 tab.

  16. A 50,000-year record of climate oscillations from Florida and its temporal correlation with the heinrich events.

    PubMed

    Grimm, E C; Jacobson, G L; Watts, W A; Hansen, B C; Maasch, K A

    1993-07-09

    Oscillations of Pinus (pine) pollen in a 50,000-year sequence from Lake Tulane, Florida, indicate that there were major vegetation shifts during the last glacial cycle. Episodes of abundant Pinus populations indicate a climate that was more wet than intervening phases dominated by Quercus (oak) and Ambrosia-type (ragweed and marsh-elder). The Pinus episodes seem to be temporally correlated with the North Atlantic Heinrich events, which were massive, periodic advances of ice streams from the eastern margin of the Laurentide Ice Sheet. Possible links between the Tulane Pinus and Heinrich events include hemispheric cooling, the influences of Mississippi meltwater on sea-surface temperatures in the Gulf of Mexico, and the effects of North Atlantic thermohaline circulation on currents in the Gulf.

  17. A 50,000-Year Record of Climate Oscillations from Florida and Its Temporal Correlation with the Heinrich Events

    NASA Astrophysics Data System (ADS)

    Grimm, Eric C.; Jacobson, George L., Jr.; Watts, William A.; Hansen, Barbara C. S.; Maasch, Kirk A.

    1993-07-01

    Oscillations of Pinus (pine) pollen in a 50,000-year sequence from Lake Tulane, Florida, indicate that there were major vegetation shifts during the last glacial cycle. Episodes of abundant Pinus populations indicate a climate that was more wet than intervening phases dominated by Quercus (oak) and Ambrosia-type (ragweed and marsh-elder). The Pinus episodes seem to be temporally correlated with the North Atlantic Heinrich events, which were massive, periodic advances of ice streams from the eastern margin of the Laurentide Ice Sheet. Possible links between the Tulane Pinus and Heinrich events include hernispheric cooling, the influences of Mississippi meltwater on seasurface temperatures in the Gulf of Mexico, and the effects of North Atlantic thermohaline circulation on currents in the Gulf.

  18. A methodology for interactive mining and visual analysis of clinical event patterns using electronic health record data.

    PubMed

    Gotz, David; Wang, Fei; Perer, Adam

    2014-04-01

    Patients' medical conditions often evolve in complex and seemingly unpredictable ways. Even within a relatively narrow and well-defined episode of care, variations between patients in both their progression and eventual outcome can be dramatic. Understanding the patterns of events observed within a population that most correlate with differences in outcome is therefore an important task in many types of studies using retrospective electronic health data. In this paper, we present a method for interactive pattern mining and analysis that supports ad hoc visual exploration of patterns mined from retrospective clinical patient data. Our approach combines (1) visual query capabilities to interactively specify episode definitions, (2) pattern mining techniques to help discover important intermediate events within an episode, and (3) interactive visualization techniques that help uncover event patterns that most impact outcome and how those associations change over time. In addition to presenting our methodology, we describe a prototype implementation and present use cases highlighting the types of insights or hypotheses that our approach can help uncover.

  19. Mid Holocene Evidence of High Energy Events in the Geological Record: Sedimentary Deposits from Cauvery Delta Coast, SE Coast of India.

    NASA Astrophysics Data System (ADS)

    Karthikeyan, A.; Seshachalam, S.; Jonathan, M. P.; Roy, P. D.

    2014-12-01

    The Cauvery Basin is one of the important sedimentary basins of southern India and provides information on geological processes since the Cretaceous. Most of the studies in the basin have been carried out on the sediments representing Cretaceous with less emphasis on the Quaternary period with marine high energy event. In the present study, we present the sedimentological and micro fauna assemblages in the 150 cm long trench from the Kameshwaram village, Nagapattinam District, South East Coast of India, in order to reconstruct the past event. OSL and Carbon dating of sand layer sediments from the Cauvery Basin provide the first proxy-record of marine event from the region over the Mid Holocene. A multi proxy approach using trench sediments from Cauvery Delta Coast, East coast of Tamil Nadu provides a high resolution record of high energy event. The dating of the event layer indicates 6 and 8 kyrs also below the layer shell layer was preserved, the radio carbon date of the shell layer was 6545 BC. A combination of sedimentological parameters of grain size, sorting, geochemical analysis (XRF) of Fe, Mn, Ti, Cr, Cu, Ni, Sr, Zr and foraminifera species like Ammonia beccarri, Ammonia dentate and Asterorotalia trispinosa were identified. The sediment layers have thinning-up sequences and it starts from 130 cm to the bottom of the layer 150 cm which included shell debris, and rip-up clasts. In addition, characteristic variations in elemental content at the bottom units of Zr, Ti, Ca is showing higher concentration, which is an indicator of high-energy depositional event often associated with an increase in Ti (2.08 % to 16.016 %) and Sr (116 ppm to 275 ppm). Ca on the other hand suggests a marine influence and Fe, Mn, Cr, Ni values are showing lower concentration indicating that the high marine energy event had inundated the Nagapattinam district in SE coast of India. Based on the multiproxy evidences, we conclude that this could be a major marine event during the Mid

  20. Carbon cycle perturbations recorded by δ13C of bulk organic matter: the Carnian Pluvial Event in the Dolomites, northern Italy

    NASA Astrophysics Data System (ADS)

    Preto, Nereo; Breda, Anna; Dal Corso, Jacopo; Rigo, Manuel; Roghi, Guido; Spötl, Christoph

    2015-04-01

    A period of increased rainfall occurred in the Carnian (Late Triassic), known as Carnian Pluvial Event (CPE), which is evidenced by major lithological changes in continental and marine successions at tropical latitudes. Increased continental weathering and erosion led to the supply of large amounts of siliciclastics into the marginal basins of the Tethys. Seawater anoxia is also observed locally in semi-restricted basins. Simultaneously, microbial factories on high-relief carbonate platforms were replaced by metazoan factories, forming low-relief carbonate ramps and mixed low-gradient shelves. This environmental change has been shown to be closely associated with a negative carbon isotope excursion. A negative δ13C shift is recorded by bulk organic matter in the Milieres section (central Dolomites) and parallels a coeval excursion in carbon-isotope records of higher plant and marine algal biomarker, thus testifying a global change in the isotopic composition of carbon dioxide in the atmosphere and of dissolved inorganic carbon (DIC) in the ocean. This isotopic excursion was identified in organic carbon records throughout the western Tethys, but so far could not be reproduced convincingly using carbon isotope records from carbonate. A long carbon isotope record was produced from bulk organic matter of the early to late Carnian Milieres - Dibona section in the Dolomites, northern Italy. Carbon isotope analyses of carbonate (limestone and dolomite) were also obtained. This new carbon isotope record illustrates the structure of this complex carbon cycle perturbation related to the CPE. But while sharp carbon isotope oscillations are evident in the bulk organic carbon record, there is no evidence of a similar pattern in carbonate record. It can be shown that the carbon isotope record of carbonates is influenced by fractionation and diagenetic processes that completely obliterated the original δ13C signal. We conclude that the Carnian carbonates of the Dolomites do not

  1. Improved tremor and LP event locations using station-corrected waveforms: applications to data recorded with a small aperture array at Fuego volcano, Guatemala

    NASA Astrophysics Data System (ADS)

    Waite, G. P.; Lyons, J. J.

    2010-12-01

    Accurate Green functions are required in order to determine the source mechanisms of low-frequency seismic events on volcanoes. Given the steep topography and alternating layers of ash and lava flows found on many volcanoes, this is particularly difficult for LP band (.5-5 Hz) tremor and discrete events. We have found that large variations in signals from LPs and tremor recorded on a small-aperture array near the active vent of Fuego volcano, Guatemala are primarily due to station site effects. This variation complicates array analyses that rely on waveform similarity and results in poorly-resolved slowness parameters. We use an iterative approach to correct for the site effects for a class of repetitive LP events and then apply those corrections to investigate non-harmonic tremor in the same frequency band. Fuego volcano, Guatemala, is an open-vent basaltic-andesite stratovolcano characterized by nearly constant, but varied low-level eruptive activity since 1999. In January 2008, we deployed small antennas of six broadband seismic and five acoustic sensors 900 m north of the active vent to investigate the source of explosions and low-frequency seismicity. The seismic array had stations spaced 30 m apart, a total aperture of ~140 m, and was deployed on the western side of a long ridge that extends from the active vent to an older portion of the edifice to the north. The infrasound sensors were deployed in a similar array, but with average station spacing of 50 m. There was no lava effusion during the deployment, but explosions were recorded approximately once per hour, with varied amounts of ash and durations from 20-150 s. In addition to the explosions, our seismic array recorded narrow band tremor with dominant frequencies of 1.6 and 1.9 Hz and discrete events that were not generally detected by the acoustic array. The dominant class of these events, which repeated approximately 10-15 times per hour, had an impulsive onset with first motion toward the vent, a

  2. The methane record of Daansgard-Oeschger event 17 in Vostok 4G-2 ice core: effects of layered bubble trapping and smoothing

    NASA Astrophysics Data System (ADS)

    Fourteau, Kévin; Faïn, Xavier; Martinerie, Patricia; Landais, Amaëlle; Ekaykin, Alexey A.; Lipenkov, Vladimir Ya.; Chappellaz, Jérôme

    2017-04-01

    This work aims to characterise and quantify the modification and loss of past atmospheric information recorded in ice cores due to gas trapping mechanisms. For this purpose a very high resolution methane record of the DO event 17 in Vostok 4G-2 ice core has been measured by continuous flow analysis and laser spectroscopy. This is the first time that the gas of a very low accumulation core, about 1.3cm.yr-1 ice equivalent, is measured using a continuous method. The measurements reveal numerous anomalous layers a couple of centimetres thick. These anomalous layers differ in methane mixing ratio from adjacent layers by about plus or minus 50ppbv. Their amplitude and uneven distribution along the ice core can be reproduced by a simple layered bubble trapping model. After removing the layering anomalies, the DO 17 recorded in the Vostok core is clearly smoother than in the WAIS Divide record, a much higher accumulation rate site. This is consistent with previous observations and general understanding, since high accumulation firns sink and densify faster and the trapping phase of gases is less spread over time. However the smoothing of the DO event in the Vostok ice core turns out to be less important and to contain higher frequencies than expected. Finally we developed a method to infer the gas age distribution enclosed in ice cores by comparison with a high frequency atmospheric scenario, such as the WAIS Divide record. This approach allows to constrain gas age distributions in climatic conditions which have no modern analogue.

  3. Practical modifications to the Time-to-Event Continual Reassessment Method for phase I cancer trials with fast patient accrual and late-onset toxicities

    PubMed Central

    Polley, Mei-Yin C.

    2014-01-01

    The goal of phase I cancer trials is to determine the highest dose of a treatment regimen with an acceptable toxicity rate. Traditional designs for phase I trials, such as the Continual Reassessment Method (CRM) and the 3+3 design, require each patient or a cohort of patients to be fully evaluated for the dose-limiting toxicity (DLT) before new patients can be enrolled. As such, the trial duration may be prohibitively long. The Time-to-Event Continual Reassessment Method (TITE-CRM, Cheung and Chappell, 2000) circumvents this limitation by allowing staggered patient accrual without the need for complete DLT follow-up of previously treated patients. However, in the setting of fast patient accrual and late-onset toxicities, the TITE-CRM results in overly aggressive dose escalation and exposes a considerable number of patients to toxic doses. We examine a modification to the TITE-CRM proposed by the original TITE-CRM creator and propose an alternative approach useful in this setting by incorporating an accrual suspension rule. A simulation study designed based on a neuro-oncology trial indicates that the modified methods provide a much improved degree of safety than the TITE-CRM while maintaining desirable design accuracy. The practical aspects of the proposed designs are discussed. The modifications presented are useful when planning phase I trials involving chemoradiation therapy. PMID:21590790

  4. Advance Liquid Metal Reactor Discrete Dynamic Event Tree/Bayesian Network Analysis and Incident Management Guidelines (Risk Management for Sodium Fast Reactors)

    SciTech Connect

    Denman, Matthew R.; Groth, Katrina M.; Cardoni, Jeffrey N.; Wheeler, Timothy A.

    2015-04-01

    Accident management is an important component to maintaining risk at acceptable levels for all complex systems, such as nuclear power plants. With the introduction of self-correcting, or inherently safe, reactor designs the focus has shifted from management by operators to allowing the system's design to manage the accident. Inherently and passively safe designs are laudable, but nonetheless extreme boundary conditions can interfere with the design attributes which facilitate inherent safety, thus resulting in unanticipated and undesirable end states. This report examines an inherently safe and small sodium fast reactor experiencing a beyond design basis seismic event with the intend of exploring two issues : (1) can human intervention either improve or worsen the potential end states and (2) can a Bayesian Network be constructed to infer the state of the reactor to inform (1). ACKNOWLEDGEMENTS The authors would like to acknowledge the U.S. Department of Energy's Office of Nuclear Energy for funding this research through Work Package SR-14SN100303 under the Advanced Reactor Concepts program. The authors also acknowledge the PRA teams at Argonne National Laboratory, Oak Ridge National Laboratory, and Idaho National Laboratory for their continue d contributions to the advanced reactor PRA mission area.

  5. Multi-century tree-ring precipitation record reveals increasing frequency of extreme dry events in the upper Blue Nile River catchment.

    PubMed

    Mokria, Mulugeta; Gebrekirstos, Aster; Abiyu, Abrham; Van Noordwijk, Meine; Bräuning, Achim

    2017-07-16

    Climate-related environmental and humanitarian crisis are important challenges in the Great Horn of Africa (GHA). In the absence of long-term past climate records in the region, tree-rings are valuable climate proxies, reflecting past climate variations and complementing climate records prior to the instrumental era. We established annually resolved multi-century tree-ring chronology from Juniperus procera trees in northern Ethiopia, the longest series yet for the GHA. The chronology correlates significantly with wet-season (r = .64, p < .01) and annual (r = .68, p < .01) regional rainfall. Reconstructed rainfall since A.D. 1811 revealed significant interannual variations between 2.2 and 3.8 year periodicity, with significant decadal and multidecadal variations during 1855-1900 and 1960-1990. The duration of negative and positive rainfall anomalies varied between 1-7 years and 1-8 years. Approximately 78.4% (95%) of reconstructed dry (extreme dry) and 85.4% (95%) of wet (extreme wet) events lasted for 1 year only and corresponded to historical records of famine and flooding, suggesting that future climate change studies should be both trend and extreme event focused. The average return periods for dry (extreme dry) and wet (extreme wet) events were 4.1 (8.8) years and 4.1 (9.5) years. Extreme-dry conditions during the 19th century were concurrent with drought episodes in equatorial eastern Africa that occurred at the end of the Little Ice Age. El Niño and La Niña events matched with 38.5% and 50% of extreme-dry and extreme-wet events. Equivalent matches for positive and negative Indian Ocean Dipole events were weaker, reaching 23.1 and 25%, respectively. Spatial correlations revealed that reconstructed rainfall represents wet-season rainfall variations over northern Ethiopia and large parts of the Sahel belt. The data presented are useful for backcasting climate and hydrological models and for developing regional strategic plans to manage scarce and

  6. CareTrack Kids-part 3. Adverse events in children's healthcare in Australia: study protocol for a retrospective medical record review.

    PubMed

    Hibbert, Peter D; Hallahan, Andrew R; Muething, Stephen E; Lachman, Peter; Hooper, Tamara D; Wiles, Louise K; Jaffe, Adam; White, Les; Wheaton, Gavin R; Runciman, William B; Dalton, Sarah; Williams, Helena M; Braithwaite, Jeffrey

    2015-04-08

    A high-quality health system should deliver care that is free from harm. Few large-scale studies of adverse events have been undertaken in children's healthcare internationally, and none in Australia. The aim of this study is to measure the frequency and types of adverse events encountered in Australian paediatric care in a range of healthcare settings. A form of retrospective medical record review, the Institute of Healthcare Improvement's Global Trigger Tool, will be modified to collect data. Records of children aged <16 years managed during 2012 and 2013 will be reviewed. We aim to review 6000-8000 records from a sample of healthcare practices (hospitals, general practices and specialists). Human Research Ethics Committee approvals have been received from the Sydney Children's Hospital Network, Children's Health Queensland Hospital and Health Service, and the Women's and Children's Hospital Network in South Australia. An application is under review with the Royal Australian College of General Practitioners. The authors will submit the results of the study to relevant journals and undertake national and international oral presentations to researchers, clinicians and policymakers. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  7. CareTrack Kids—part 3. Adverse events in children's healthcare in Australia: study protocol for a retrospective medical record review

    PubMed Central

    Hibbert, Peter D; Hallahan, Andrew R; Muething, Stephen E; Lachman, Peter; Hooper, Tamara D; Wiles, Louise K; Jaffe, Adam; White, Les; Wheaton, Gavin R; Runciman, William B; Dalton, Sarah; Williams, Helena M; Braithwaite, Jeffrey

    2015-01-01

    Introduction A high-quality health system should deliver care that is free from harm. Few large-scale studies of adverse events have been undertaken in children's healthcare internationally, and none in Australia. The aim of this study is to measure the frequency and types of adverse events encountered in Australian paediatric care in a range of healthcare settings. Methods and analysis A form of retrospective medical record review, the Institute of Healthcare Improvement's Global Trigger Tool, will be modified to collect data. Records of children aged <16 years managed during 2012 and 2013 will be reviewed. We aim to review 6000–8000 records from a sample of healthcare practices (hospitals, general practices and specialists). Ethics and dissemination Human Research Ethics Committee approvals have been received from the Sydney Children's Hospital Network, Children's Health Queensland Hospital and Health Service, and the Women's and Children's Hospital Network in South Australia. An application is under review with the Royal Australian College of General Practitioners. The authors will submit the results of the study to relevant journals and undertake national and international oral presentations to researchers, clinicians and policymakers. PMID:25854978

  8. U-Th dating of broken speleothems from Cacahuamilpa cave, Mexico: Are they recording past seismic events?

    NASA Astrophysics Data System (ADS)

    Méjean, Pauline; Garduño-Monroy, Victor-Hugo; Pinti, Daniele L.; Ghaleb, Bassam; Bouvier, Laura; Gomez-Vasconcelos, Martha G.; Tremblay, Alain

    2015-01-01

    Cacahuamilpa cave is one of the largest karst systems in Central Mexico. The cave contains numerous massive speleothems broken and fallen following oriented directions, damaged during cataclysmic geological events. One fallen and two broken speleothems were sampled in the Cacahuamilpa cave for dating the rupture event using measured U-Th disequilibrium ages. A total of eight small carbonate cores were drilled perpendicular and longitudinal to the rupture surface. Results showed three groups of ages (weighted average): 0.95 ± 0.02 ka, 28.8 ± 0.2 ka and 88.0 ± 0.7 ka. This indicates that the construction of the Cacahuamilpa karst system, for which no absolute ages existed before this study, initiated at least since Late Pleistocene. The first two groups of ages might be related to two distinct episodes of intense seismic activity. Calculated minimum horizontal ground acceleration and frequency values of the seismic events needed to create the rupture of the stalagmites dated at 0.95 ± 0.02 ka and 28.8 ± 0.2 ka range between 1.3 and 2.0 m s-2 and between 13.4 and 20.8 Hz, respectively. These parameters are compatible with earthquakes of magnitude equal or higher than 7 M, with an epicentral distance between 50 and 100 km from the Cacahuamilpa cave. The stalagmite rupture dated at 88.0 ± 0.7 ka might result from the invasion of the cave by one of the older lahars deposits of the nearby volcano Nevado del Toluca, and successively fell by gravity instability.

  9. A comparison of adverse event and fracture efficacy data for strontium ranelate in regulatory documents and the publication record

    PubMed Central

    Bolland, Mark J; Grey, Andrew

    2014-01-01

    Objective Recently, the European Medicines Agency reported that strontium ranelate increases myocardial infarction risk in postmenopausal women, 8.5 years after it was registered for use in osteoporosis. Unreported serious adverse events in clinical trials for other pharmaceuticals have been described in recent years. We assessed reporting of adverse events and fracture efficacy of strontium. Methods We compared data on adverse effects (myocardial infarction, venous thromboembolism and pulmonary embolism) and fracture efficacy of strontium in publicly available regulatory documents with data in publications retrieved from searching PubMed. Results We identified 5 regulatory documents and 9 primary publications of 7 randomised, placebo-controlled trials of strontium that reported relevant data. We identified several areas of concern in these reports: the increased risk of myocardial infarction with strontium was not identified in a pivotal phase 3 clinical trial despite specific regulatory review of cardiovascular events; data on myocardial infarction were not included in any primary publication; increased risks of venous thromboembolism and pulmonary embolism with strontium were not reported in either of the phase 3 clinical trials; data on venous thromboembolism were reported in only 5 of 9 primary publications, data on pulmonary embolism in only 2 of 9 primary publications, and either was discussed in <50% of subsequent review articles. There were differences in participant numbers, fracture cases and venous thromboembolism cases between regulatory documents and primary publications. Based on all available data from primary publications and regulatory documents, the number of fractures prevented by strontium use is similar to the number of extra cases of venous thromboembolism, pulmonary embolism and myocardial infarction caused by strontium use. Conclusions The risks of strontium use are similar to the benefits. Full disclosure of the clinical trial data and

  10. Climate Change and Drought Events in the Geochemical Records of the Lacustrine Deposits in the Southeastern Tibetan Plateau

    PubMed Central

    Shi, Zhengtao; Niu, Jie; Su, Huai

    2016-01-01

    Lacustrine deposits at the margin of the southeastern Tibetan Plateau (SETP) are sensitive indicators for the evolution of the southwest Asian monsoon (SWAM) during the Quaternary. Thus, they can provide insight into the Quaternary climatic history and their relationship with global climatic changes. The results of the geochemical analysis of the Xiaozhongdian Basin section at the SETP suggest that SiO2 had the highest content of the major elements followed by Al2O3. The order of the abundance of the major elements was generally as follows: SiO2>Al2O3>Fe2O3>CaO>MgO>K2O>TiO2>Na2O>MnO2. The geochemical proxies, such as chemical index of alteration (CIA), the index of compositional variability (ICV) and (CaO+K2O+Na2O)/Al2O3, indicate the weak chemical weathering and the aridification of the margin of the SETP during the Heinrich events. In addition, the aridification of the SETP during the Heinrich events may be closely related to the cold signals transmitted from the high latitudes of the North Atlantic to the TP, and the effect caused the cooling effect to be very strong on the TP as a result of the upper-level westerly jet stream and then reduced the suction action associated with the SWAM, thus accelerating the drying rate of Xiaozhongdian Basin, which was amplifying the degree of drought in Heinrich events. PMID:28033377

  11. Statistical study of ELF/VLF emissions recorded by a low-altitude satellite during seismic events

    SciTech Connect

    Parrot, M.

    1994-12-01

    The author reports a study of correlations between 325 earthquakes registering M{sub s}>5, and frequency filtered data observed by the low altitude satellite AUREOL 3 within a 24 hour window around the event. Data is sorted by time difference, difference in longitude, and difference in invariant latitude, between the satellite location and the epicenter. It is found that for the averaged data, the strongest signals are observed when the longitudinal differences are less than 10{degrees}, independent of latitude. The collected data was not continuous in nature, and therefore limits the nature of the statistical study which can be done.

  12. 20th century global warming favoured enhanced intensity of extreme torrential events - a proglacial sediment record in NW French Alps

    NASA Astrophysics Data System (ADS)

    Wilhelm, B.; Arnaud, F.; Legaz, A.; Allignol, F.; Enters, D.; Revillon, S.

    2009-04-01

    During the past few yeas, considerable climate changes have been observed at high elevation areas of the European Alps. Additionally, one of the main results of high resolution climate modelling is a trend towards both dryer summer conditions and enhanced risk of extreme floods. This should have particularly dramatic consequences in alpine areas. Indeed, the development of tourism during the 20th century in the Alps and the rise of population density resulted in an increasing potential risk from natural hazards. Among them, torrential floods are some of the most common and widespread ones. They cause both loss of human life and high damage to property and infrastructure and are particularly destructive in mountain areas. For example, in August 2005, an unusual meteorological situation resulted in a series of catastrophic floods in most regions of the European Alps and particularly in the catchment of the Vorz river, downstream of proglacial Lac Blanc (2170 m a.s.l., Belledonne range, NW French Alps). We studied a series of sediment cores from Lac Blanc, spanning the last ca. 250 years. Through a coupled high resolution sedimentological and geochemical approach we documented about 100 flood deposits and measured their thickness. The age of each deposit has been assessed by radiochemical dating and the recognition of historically-known events - major earthquakes and historical atmospheric lead deposition. Furthermore, a detailed study of regional and local historical archives was conducted allowing us to relate the recognised flood deposits to the ones reported by local population. We hence obtained a flood calendar from 1740 to 2005 with the respective intensity of each event assessed by the thickness of the associated deposit. The flood frequency shows an important and punctual increase at the early end of the Little Ice Age (1830 - 1860) as a response to the beginning warming period, which was emphasized by the synchronous local glacier retreat. On the other hand

  13. The record of Tethyan planktonic foraminifera at the early Paleogene hyperthermal events and Middle Eocene Climatic Optimum in northeastern Italy: are they comparable?

    NASA Astrophysics Data System (ADS)

    Luciani, Valeria; Giusberti, Luca; Agnini, Claudia; Fornaciari, Eliana; Rio, Domenico

    2010-05-01

    The early Paleogene is one of the more climatically and evolutionary dynamic periods in the Earth history that records a pronounced warming trend peaking in the Early Eocene, and a successive composite transition towards the modern icehouse world. Ever increasingly scientific attention is dedicated to definitely comprehend timing, nature and characters of the complex, non-linear evolution of the Paleogene climate. Several complete and expanded Paleogene successions (Forada, Possagno, Alano, Farra), with a sound magneto-biochronostratigraphic and stable isotope record crop out in the Venetian Southern Alps (Northeast Italy). Recent studies (Giusberti et. al., 2007; Luciani et al., 2007; Agnini et al., 2008) and unpublished data document the presence in these section of the main short-lived warming events (hyperthermals) of the Eocene (Paleocene-Eocene Thermal Maximum, PETM, ca 55 Ma, Eocene Layer of Mysterious Origin (ELMO, ca 53,6 Ma), X-event (ca 52.5 Ma), of the Early Eocene Climatic Optimum (EECO, ca 50-52 Ma) and of the Middle Eocene Climatic Optimum (MECO, ca 40 Ma; Zachos et al., 2001. 2008). All these events are typified by marked negative shifts in δ13C curves that correspond to carbonate decrease related to rise of the carbonate compensation depth in turn induced by large introduction in the ocean-atmosphere system of CO2. Common features to the warming events are pronounced and complex changes in planktonic foraminiferal assemblages, indicating strong environmental perturbations that perfectly parallel the variations of the stable isotope curves in all the examined events. These strict correspondences indicate close cause-effect relationships between changes in environmental conditions and modifications of the assemblages. Our analysis shows that the most striking variations are recorded by the PETM and MECO assemblages that reflect highly perturbed environments. The ELMO, X-event and EECO exhibit planktic foraminiferal responses that are similar to

  14. Using the significant dust deposition event on the glaciers of Mt.~Elbrus, Caucasus Mountains, Russia on 5 May 2009 to develop a method for dating and "provenancing" of desert dust events recorded in snow pack

    NASA Astrophysics Data System (ADS)

    Shahgedanova, M.; Kutuzov, S.; White, K. H.; Nosenko, G.

    2013-02-01

    A significant desert dust deposition event occurred on Mt. Elbrus, Caucasus Mountains, Russia on 5 May 2009, where the deposited dust later appeared as a brown layer in the snow pack. An examination of dust transportation history and analysis of chemical and physical properties of the deposited dust were used to develop a new approach for high-resolution "provenancing" of dust deposition events recorded in snow pack using multiple independent techniques. A combination of SEVIRI red-green-blue composite imagery, MODIS atmospheric optical depth fields derived using the Deep Blue algorithm, air mass trajectories derived with HYSPLIT model and analysis of meteorological data enabled identification of dust source regions with high temporal (hours) and spatial (ca. 100 km) resolution. Dust, deposited on 5 May 2009, originated in the foothills of the Djebel Akhdar in eastern Libya where dust sources were activated by the intrusion of cold air from the Mediterranean Sea and Saharan low pressure system and transported to the Caucasus along the eastern Mediterranean coast, Syria and Turkey. Particles with an average diameter below 8 μm accounted for 90% of the measured particles in the sample with a mean of 3.58 μm, median 2.48 μm. The chemical signature of this long-travelled dust was significantly different from the locally-produced dust and close to that of soils collected in a palaeolake in the source region, in concentrations of hematite. Potential addition of dust from a secondary source in northern Mesopotamia introduced uncertainty in the "provenancing" of dust from this event. Nevertheless, the approach adopted here enables other dust horizons in the snowpack to be linked to specific dust transport events recorded in remote sensing and meteorological data archives.

  15. Using the significant dust deposition event on the glaciers of Mt. Elbrus, Caucasus Mountains, Russia on 5 May 2009 to develop a method for dating and provenancing of desert dust events recorded in snow pack

    NASA Astrophysics Data System (ADS)

    Shahgedanova, M.; Kutuzov, S.; White, K.; Nosenko, G.

    2012-09-01

    A significant desert dust deposition event occurred on Mt. Elbrus, Caucasus Mountains, Russia on 5 May 2009, where the deposited dust later appeared as a brown layer in the snow pack. An examination of dust transportation history and analysis of chemical and physical properties of the deposited dust were used to develop a new approach for high-resolution provenancing of dust deposition events recorded in snow pack using multiple independent techniques. A combination of SEVIRI red-green-blue composite imagery, MODIS atmospheric optical depth fields derived using the Deep Blue algorithm, air mass trajectories derived with HYSPLIT model and analysis of meteorological data enabled identification of dust source regions with high temporal (hours) and spatial (ca. 100 km) resolution. Dust, deposited on 5 May 2009, originated in the foothills of the Djebel Akhdar in eastern Libya where dust sources were activated by the intrusion of cold air from the Mediterranean Sea and Saharan low pressure system and transported to the Caucasus along the eastern Mediterranean coast, Syria and Turkey. Particles with an average diameter below 8 μm accounted for 90% of the measured particles in the sample with a mean of 3.58 μm, median 2.48 μm and the dominant mode of 0.60 μm. The chemical signature of this long-travelled dust was significantly different from the locally-produced dust and close to that of soils collected in a palaeolake in the source region, in concentrations of hematite and oxides of aluminium, manganese, and magnesium. Potential addition of dust from a secondary source in northern Mesopotamia introduced uncertainty in the provenancing of dust from this event. Nevertheless, the approach adopted here enables other dust horizons in the snowpack to be linked to specific dust transport events recorded in remote sensing and meteorological data archives.

  16. Biomarkers from Huronian oil-bearing fluid inclusions: An uncontaminated record of life before the Great Oxidation Event

    NASA Astrophysics Data System (ADS)

    Dutkiewicz, Adriana; Volk, Herbert; George, Simon C.; Ridley, John; Buick, Roger

    2006-06-01

    We report detailed molecular geochemistry of oil-bearing fluid inclusions from a ca. 2.45 Ga fluvial metaconglomerate of the Matinenda Formation at Elliot Lake, Canada. The oil, most likely derived from the conformably overlying McKim Formation, was trapped in quartz and feldspar during diagenesis and early metamorphism of the host rock, probably before ca. 2.2 Ga. The presence of abundant biomarkers for cyanobacteria and eukaryotes derived from and trapped in rocks deposited before the Great Oxidation Event is consistent with an earlier evolution of oxygenic photosynthesis than previously thought and suggests that some aquatic settings had become sufficiently oxygenated for sterol biosynthesis by this time. It also implies that eukaryotes survived several extreme climatic events, including the Paleoproterozoic “snowball Earth” glaciations. The extraction of biomarker molecules from Paleoproterozoic oil-bearing fluid inclusions thus establishes a new method, using low detection limits and system blank levels, to trace evolution of life through Earth's early history that avoids the potential contamination problems affecting shale-hosted hydrocarbons.

  17. Late Pleistocene and Holocene palaeoflood events recorded by slackwater deposits in the upper Hanjiang River valley, China

    NASA Astrophysics Data System (ADS)

    Liu, Tao; Huang, Chun Chang; Pang, Jiangli; Zha, Xiaochun; Zhou, Yali; Zhang, Yuzhu; Ji, Lin

    2015-10-01

    Slackwater palaeoflood deposits (SWDs) were identified in a bedrock gorge in the upper reaches of the Hanjiang River of central China. The Hanjiang River is the longest tributary of the Yangtze River, one of the most flood-prone rivers in China, and the main source of water for the South-to-North Water Transfer Project (SNWTP). Three main loess-soil profiles with late Pleistocene and Holocene palaeoflood SWD bedsets were found. Palaeoflood SWDs identified interbedded in the loess-soil sequence of late Pleistocene and Holocene age within the cliff riverbanks were studied by field observations and laboratory analysis, including particle-size distribution and Optically Stimulated Luminescence (OSL) dating. At least eight extreme flood events documented by palaeoflood SWDs occurred in the Wufeng reaches of the upper Hanjiang River. The discharge estimation associated with palaeoflood SWDs, indicates that the minimum flood peak discharges of these flood episodes range from 42,220 to 63,400 m3/s. The SWDs were OSL dated to between 12,600-12,400, 4200-4000, 3200-2800 and 1900-1700 a BP and these dates were corroborated with pottery remains retrieved from the profiles and dated by archaeological methods. These periods of increased flood magnitude coincide with contemporaneous global climatic events dated to 12,500, 4200, 3100 and 1900 a BP worldwide. These findings are of great significance in understanding the interactions between hydrological systems and climatic change in monsoonal zones.

  18. Arrhythmia burden in elderly patients with severe aortic stenosis as determined by continuous electrocardiographic recording: toward a better understanding of arrhythmic events after transcatheter aortic valve replacement.

    PubMed

    Urena, Marina; Hayek, Salim; Cheema, Asim N; Serra, Vicenç; Amat-Santos, Ignacio J; Nombela-Franco, Luis; Ribeiro, Henrique B; Allende, Ricardo; Paradis, Jean-Michel; Dumont, Eric; Thourani, Vinod H; Babaliaros, Vasilis; Francisco Pascual, Jaume; Cortés, Carlos; Del Blanco, Bruno García; Philippon, François; Lerakis, Stamatios; Rodés-Cabau, Josep

    2015-02-03

    This study sought to evaluate the prevalence of previously undiagnosed arrhythmias in candidates for transcatheter aortic valve replacement (TAVR) and to determine the impact on therapy changes and arrhythmic events after the procedure. A total of 435 candidates for TAVR underwent 24-hour continuous ECG monitoring the day before the procedure. Newly diagnosed arrhythmias were observed in 70 patients (16.1%) before TAVR: paroxysmal atrial fibrillation (AF)/atrial tachycardia (AT) in 28, advanced atrioventricular block or severe bradycardia in 24, nonsustained ventricular tachycardia in 26, and intermittent left bundle-branch block in 3 patients. All arrhythmic events but one were asymptomatic and led to a therapy change in 43% of patients. In patients without known AF/AT, the occurrence of AF/AT during 24-hour ECG recording was associated with a higher rate of 30-day cerebrovascular events (7.1% versus 0.4%; P=0.030). Among the 53 patients with new-onset AF/AT after TAVR, 30.2% had newly diagnosed paroxysmal AF/AT before the procedure. In patients who needed permanent pacemaker implantation after the procedure (n=35), 31.4% had newly diagnosed advanced atrioventricular block or severe bradycardia before TAVR. New-onset persistent left bundle-branch block after TAVR occurred in 37 patients, 8.1% of whom had intermittent left bundle-branch block before the procedure. Newly diagnosed arrhythmias were observed in approximately a fifth of TAVR candidates, led to a higher rate of cerebrovascular events, and accounted for a third of arrhythmic events after the procedure. This high arrhythmia burden highlights the importance of an early diagnosis of arrhythmic events in such patients to implement the appropriate therapeutic measures earlier. © 2014 American Heart Association, Inc.

  19. Utilization of Electronic Health Record Events to Conduct a Tuberculosis Contact Investigation in a High-Risk Oncology Unit.

    PubMed

    Usiak, Shauna C; Romero, Fabian A; Schwegman, Patrice; Fitzpatrick, Violet; Connor, MaryAnn; Eagan, Janet; Brown, Arthur E; Kamboj, Mini

    2017-10-01

    OBJECTIVE To describe the utilization of electronic medical data resources, including health records and nursing scheduling resources, to conduct a tuberculosis (TB) exposure investigation in a high-risk oncology unit. SETTING A 42-bed inpatient unit with a mix of surgical and medical patients at a large tertiary-care cancer center in New York City. PARTICIPANTS High-risk subjects and coworkers exposed to a healthcare worker (HCW) with cavitary smear positive lung TB. RESULTS During the 3-month exposure period, 270 patients were admitted to the unit; 137 of these (50.7%) received direct care from the index case HCW. Host immune status and intensity of exposure were used to establish criteria for postexposure testing, and 63 patients (45%) met these criteria for first-tier postexposure testing. No cases of active TB occurred. Among coworkers, 146 had significant exposure (ie, >8 hours cumulative). In the 22-month follow-up period after the exposure, no purified protein derivative or interferon gamma release assay conversions or active cases of TB occurred among exposed HCWs or patients. CONCLUSIONS Electronic medical records and employee scheduling systems are useful resources to conduct otherwise labor-intensive contact investigations. Despite the high-risk features of our index case, a highly vulnerable immunocompromised patient population, and extended proximity to coworkers, we did not find any evidence of transmission of active or latent tuberculosis infection among exposed individuals. Infect Control Hosp Epidemiol 2017;38:1235-1239.

  20. Millennial pulsing of environmental change in southern California from the past 24 k.y.: A record of Indo-Pacific ENSO events?

    NASA Astrophysics Data System (ADS)

    Heusser, L. E.; Sirocko, F.

    1997-03-01

    Century-long variations in coastal California vegetation inferred from polliniferous sediments deposited in the Santa Barbara basin record a succession of brief (<200 yr duration) climatic events that recurred at ˜1000 yr intervals (8.8, 10.4, 11.2, 12.1, 12.7, 13.4, 13.9, 14.6, 15.4, 16.1, and 17.1 × 1000 14C yr B.P. [ka]). These millennial-scale pulses, many of which correspond with western Great Basin hydrological fluctuations, are also linked to events of southwest monsoon intensification in southern Asia. We suggest that these correlative high-frequency variations in the Asian summer and northeast Pacific winter climates may reflect submillennial-scale El NiñO/Southern Oscillation (ENSO)-type forcing involving water vapor transport over the Indian and Pacific Oceans.

  1. The Cadmium Isotope Record of the Great Oxidation Event from the Turee Creek Group, Hamersley Basin, Australia

    NASA Astrophysics Data System (ADS)

    Abouchami, W.; Busigny, V.; Philippot, P.; Galer, S. J. G.; Cheng, C.; Pecoits, E.

    2016-12-01

    The evolution of the ocean, atmosphere and biosphere throughout Earth's history has impacted on the biogeochemistry of some key trace metals that are of particular importance in regulating the exchange between Earth's reservoirs. Several geochemical proxies exhibit isotopic shifts that have been linked to major changes in the oxygenation levels of the ancient oceans during the Great Oxygenation Event (GOE) between 2.45 and 2.2 Ga and the Neoproterozoic Oxygenation Event at ca. 0.6 Ga. Studies of the modern marine biogeochemical cycle of the transition metal Cadmium have shown that stable Cd isotope fractionation is mainly driven by biological uptake of light Cd into marine phytoplankton in surface waters leaving behind the seawater enriched in the heavy Cd isotopes. Here we use of the potential of this novel proxy to trace ancient biological productivity which remains an enigma, particularly during the early stages of Earth history. The Turee Creek Group in the Hamersley Basin, Australia, provides a continuous stratigraphic sedimentary section covering the GOE and at least two glacial events, offering a unique opportunity to examine the changes that took place during these periods and possibly constrain the evolution, timing and onset of oxygenic photosynthesis. Stable Cd isotope data were obtained on samples from the Boolgeeda Iron Fm. (BIFs), the siliciclastic and carbonate successions of Kungara (including the Meteorite Bore Member) and the Kazputt Fm., using a double spike technique by TIMS (ThermoFisher Triton) and Cd concentrations were determined by isotope dilution. The Boolgeeda BIFs have generally low Cd concentrations varying between 8 and 50ppb, with two major excursions marked by an increase in Cd content, reaching similar levels to those in the overlying Kungarra Fm. (≥150 ppb). These variations are associated with a large range in ɛ112/110Cd values (-2 to +2), with the most negative values typically found in the organic and Cd-rich shales and

  2. Extreme event archived in the geological record of the Japan Trench: New results from R/V Sonne Cruise SO-251 towards establishing J-TRACK paleoseismology

    NASA Astrophysics Data System (ADS)

    Strasser, Michael; Kopf, Achim; Kanamatsu, Toshyia; Moernaut, Jasper; Ikehara, Ken; McHugh, Cecila

    2017-04-01

    Our perspective of subduction zonés earthquake magnitude and recurrence is limited by short historical records. Examining prehistoric extreme events preserved in the geological record is essential towards understanding large earthquakes and assessing the geohazard potential associated with such rare events. The research field of "subaquatic paleoseismology" is a promising approach to investigate deposits from the deep sea, where earthquakes leave traces preserved in stratigraphic succession. However, at present we lack comprehensive data set that allow conclusive distinctions between quality and completeness of the paleoseismic archives as they may relate to different sediment transport, erosion and deposition processes vs. variability of intrinsic seismogenic behavior across different segments. Initially building on what sedimentary deposits were generated from the 2011 Magnitude 9 Tohoku-oki earthquake, the Japan Trench is a promising study area to investigate earthquake-triggered sediment remobilization processes and how they become embedded in the stratigraphic record. Here we present new results from the recent R/V Sonne expedition SO251 that acquired a complete high-resolution bathymetric map of the trench axis and nearly 2000 km of subbottom Parasound profiles, covering the entire along-strike extent of the Japan Trench from 36° to 40.3° N, and groundtruthed by several nearly 10m long piston cores retrieved from the very deep waters (7 to 8 km below sea level): Several smaller submarine landslide (up to several 100's m of lateral extent) can be identified along the trench axis in the new bathymetric data set. These features were either not yet present, or not resolved in the lower-resolution bathymetric dataset acquired before 2011. Sub-bottom acoustic reflection data reveals striking, up to several meter thick, acoustically transparent bodies interbedded in the otherwise parallel reflection pattern of the trench fill basins, providing a temporal and

  3. Excess warming in Central Europe after the 8.2 ka cold event: evidence from a varve-dated ostracod δ18O record from Mondsee (Austria)

    NASA Astrophysics Data System (ADS)

    Lauterbach, Stefan; Andersen, Nils; Erlenkeuser, Helmut; Danielopol, Dan L.; Namiotko, Tadeusz; Hüls, Matthias; Belmecheri, Soumaya; Nantke, Carla; Meyer, Hanno; Chapligin, Bernhard; von Grafenstein, Uli; Brauer, Achim

    2017-04-01

    As evidenced by numerous palaeoclimate records worldwide, the Holocene warm period has been punctuated by several short, low-amplitude cold episodes. Among these, the so-called 8.2 ka cold event represents a particularly prominent climate anomaly. Accordingly, several proxy-based and modeling studies have addressed its causal mechanisms, absolute dating, duration, amplitude, spatio-temporal characteristics and environmental consequences so far. However, knowledge about the dynamics and causes of subsequent climate recovery is still limited although this is essential for understanding rapid climate change. Here we present a new sub-decadally resolved and precisely dated oxygen isotope (δ18O) record for the interval 7.7-8.7 ka BP derived from benthic ostracods preserved in the varved lake sediments of pre-Alpine Mondsee (Austria), providing new insights into climate development around the 8.2 ka cold event in Central Europe. The high-resolution Mondsee δ18O record reveals the occurrence of a pronounced cold spell around 8.2 ka BP, whose amplitude (˜1.0 ‰ , equivalent to a 1.5-2.0 ˚ C cooling), total duration (151 years) and absolute dating (8231-8080 varve years BP, i.e. calendar years before AD 1950) agrees well with results from other Northern Hemisphere palaeoclimate archives, e.g. the Greenland ice cores. In addition, the Mondsee data set provides evidence for a 75-year-long δ18O overshoot directly following the 8.2 ka event (between 8080 and 8005 varve years BP), which is interpreted as a period of excess warming (about 0.5-0.6 ˚ C above the pre-8.2 ka event level) in Central Europe. Though so far not been explicitly described elsewhere, this observation is consistent with evidence from other proxy records in the North Atlantic realm, therefore likely reflecting a hemispheric-scale signal rather than a local phenomenon. As a possible trigger we suggest an enhanced resumption of the Atlantic meridional overturning circulation (AMOC), supporting

  4. Evaluation of a standardized recording tool for sputum smear microscopy for acid-fast bacilli under routine conditions in low income countries.

    PubMed

    Rieder, H L; Arnadottir, T; Tardencilla Gutierrez, A A; Kasalika, A C; Salaniponi, F L; Ba, F; Diop, A H; Anagonou, S; Gninafon, M; Ringdal, T; Trébucq, A; Enarson, D A

    1997-08-01

    Laboratories performing sputum smear microscopy for tuberculosis in Benin, Malawi, Nicaragua and Senegal. Analysis of computerized laboratory registers to ascertain workload, yield from serial smear examination, and demographic characteristics of examinees. Data from more than 60,000 examinees in 42 laboratories showed that the average number of smears examined per day ranged from 4 to 19 (mean 6) per country. To find one case of tuberculosis, on average 21 smears of suspects were examined (range 8 to 50). Of all cases with ultimately at least one positive result, 87% were already positive on the first examination. Demographic characteristics of cases differed considerably by country and gender. In 35 of 42 laboratories, males were more frequently found to be cases than females, and with increasing age an increasingly larger number of female than male suspects had to be examined to identify one case. This study demonstrates the usefulness of a standardized recording system for results of acid-fast microscopy in obtaining essential information for program management and on demographic characteristics of persons presenting for examination.

  5. Extreme events in the sedimentary record of maar Lake Pavin: Implications for natural hazards assessment in the French Massif Central

    NASA Astrophysics Data System (ADS)

    Chassiot, Léo; Chapron, Emmanuel; Di Giovanni, Christian; Albéric, Patrick; Lajeunesse, Patrick; Lehours, Anne-Catherine; Meybeck, Michel

    2016-06-01

    A set of sedimentary cores, high resolution swath bathymetry and subbottom profiler data provides new insights on sedimentary processes in meromictic maar Lake Pavin, France. Three sedimentary environments (i.e., littoral, plateau and basin) have been identified in the lake from sediment composition using bulk organic geochemistry and the analysis of hydroacoustic images. Various forms of rapidly deposited layers (RDLs) have been identified and radiocarbon dated. An up to date stratigraphy of sedimentary events matching coeval RDLs across the lake is presented and illustrates a wide range of natural hazards linked to Lake Pavin during the last 2000 years. In AD 600, a sudden lake outburst triggered a slump deposit along with a 9 m lake-level drop that drove shifts in sedimentary organic matter composition. Outside the lake, outburst flood deposits have been described downstream and provide sedimentary evidence for this event. The lake-level drop also favored the generation of gravity reworking processes, as shown by (1) a regional earthquake-triggered large slope failure on the plateau connected to a mass-wasting deposit in the basin dated to AD 1300, and (2) a succession of turbidites in AD 1825 and AD 1860 contemporaneous to two historic earthquakes, suggesting that this lake is sensitive to earthquakes with a minimum epicentral intensity of V. Finally, past observations of lake water color changes in AD 1783 and AD 1936, similar to reports in other meromictic lakes, match iron-rich deposits identified in maar lake sediments and suggest that Lake Pavin could have undergone limnic eruptions.

  6. Factors contributing to commercial vehicle rear-end conflicts in China: A study using on-board event data recorders.

    PubMed

    Bianchi Piccinini, Giulio; Engström, Johan; Bärgman, Jonas; Wang, Xuesong

    2017-09-01

    In the last 30years, China has undergone a dramatic increase in vehicle ownership and a resulting escalation in the number of road crashes. Although crash figures are decreasing today, they remain high; it is therefore important to investigate crash causation mechanisms to further improve road safety in China. To shed more light on the topic, naturalistic driving data was collected in Shanghai as part of the evaluation of a behavior-based safety service. The data collection included instrumenting 47 vehicles belonging to a commercial fleet with data acquisition systems. From the overall sample, 91 rear-end crash or near-crash (CNC) events, triggered by 24 drivers, were used in the analysis. The CNC were annotated by three researchers, through an expert assessment methodology based on videos and kinematic variables. The results show that the main factor behind the rear-end CNC was the adoption of very small safety margins. In contrast to results from previous studies in the US, the following vehicles' drivers typically had their eyes on the road and reacted quickly in response to the evolving conflict in most events. When delayed reactions occurred, they were mainly due to driving-related visual scanning mismatches (e.g., mirror checks) rather than visual distraction. Finally, the study identified four main conflict scenarios that represent the typical development of rear-end conflicts in this data. The findings of this study have several practical applications, such as informing the specifications of in-vehicle safety measures and automated driving and providing input into the design of coaching/training procedures to improve the driving habits of drivers. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. The Kamikatsura event and the Matuyama-Brunhes reversal recorded in lavas from Tjörnes Peninsula, northern Iceland

    NASA Astrophysics Data System (ADS)

    Camps, P.; Singer, B. S.; Carvallo, C.; Goguitchaichvili, A.; Fanjat, G.; Allen, B.

    2011-10-01

    We report paleomagnetic results from four overlapping stratigraphic sections (55 flows) through the lava pile in Tjörnes peninsula (North Iceland). The initial aim of our study was to check the existence of intermediate directions previously interpreted as belonging to the Matuyama-Brunhes geomagnetic reversal (MBR), and complete this record with Thellier-Thellier paleointensity determinations and 40Ar/ 39Ar radioisotopic dating. The directional results corroborate the findings by Kristjánsson et al. (1988): a sequence of reversed, transitional, normal, and transitional polarity (R-T-N-T) is found in each section. The polarity change is characterized by a jump from reversed virtual geomagnetic poles (VGPs) to a quasi-cluster of transitional VGPs located over China, followed by a second jump to a cluster of normal polarity before moving again towards intermediate polarities. Reversely magnetized flows exhibit a magnetic mineralogy well suited for paleointensity determination. Of these 25 flows, 20 yielded paleointensity estimates of good quality. Unfortunately, the systematic presence of coarse multidomain (MD) titanomagnetite in the transitional and normal polarity flows hampered paleointensity estimates for these flows. The Virtual Dipole Moments (VDM) calculated for the reversed polarity flows vary from 4.9 to 7.0 × 10 22 Am 2 with an arithmetic mean value of 5.5 ± 0.8 × 10 22 Am 2. This value is identical to the mean VDM obtained for the 0.3-5 Ma time window and thus strengthens the conclusion that the recent geomagnetic field strength is anomalously high compared to that older than 0.3 Ma. 40Ar/ 39Ar isochron ages were obtained with the incremental heating technique on groundmass separates or phenocryst-poor whole rock samples. Six of the transitionally magnetized lavas yielded isochron ages that are indistinguishable from one another at the 95% confidence level. The weighted average age is 862 ± 51 ka. In the upper part of this volcanic sequence, the

  8. Comparison of the patient-activated event recording system vs. traditional 24 h Holter electrocardiography in individuals with paroxysmal palpitations or dizziness.

    PubMed

    de Asmundis, Carlo; Conte, Giulio; Sieira, Juan; Chierchia, Gian-Battista; Rodriguez-Manero, Moises; Di Giovanni, Giacomo; Ciconte, Giuseppe; Levinstein, Moises; Baltogiannis, Giannis; Saitoh, Yukio; Casado-Arroyo, Rubén; Brugada, Pedro

    2014-08-01

    Electrocardiographic documentation of symptomatic episodes of palpitations by means of traditional methods such as 24 h Holter monitoring (HM) or loop recorders is challenging. Patient-activated electrocardiography (ECG) recorders have been proved to be a useful tool in the diagnosis of arrhythmias in these patients. However, no comparison studies between the two techniques have been conducted. The aim of this study was to compare the diagnostic value of Holter ECG and a patient-activated event recorder (OMRON portable HeartScan ECG Monitor(®)) (HeartScan) in the detection of arrhythmias in patients with paroxysmal palpitations or dizziness suggestive of cardiac arrhythmias. Patients with paroxysmal palpitations or dizziness were eligible for this study. All patients underwent an HM for 24 h and a 15-day HeartScan after the HM. Six hundred and twenty-five patients (48% male, mean age: 37 ± 11 years) were included in the study. All patients present with normal heart structure, normal baseline 12-lead ECG, and normal echocardiogram. Indications for ECG monitoring were palpitations in 577 patients (92.3%) and dizziness in 48 (7.7%). Holter monitoring offered a clinical diagnosis in 11 patients (1.8%). Conversely, HeartScan diagnosed the clinical arrhythmia in 558 individuals (89%). Detection of symptoms-related arrhythmias by means of HeartScan was significantly higher when compared with HM (P < 0.01). The studied system proved to be an efficient event recorder providing the diagnosis of the clinical arrhythmia in 89% of patients with paroxysmal palpitations or dizziness. Further studies are needed to confirm our results. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  9. Change in Mediterranean Hydrologic Cycle at Time of Heinrich Events From a High Resolution Multiproxy Record of the Last 50 kyr

    NASA Astrophysics Data System (ADS)

    Bout-Roumazeilles, V.; Combourieu Nebout, N.; Peyron, O.; Dormoy, I.

    2008-12-01

    Clay mineralogy, pollen record and pollen-based reconstructions were performed over the last climatic cycle on the Site ODP 976 (Alboran Sea, Western Mediterranean). These proxies show that several droughts occurred during the past 50 kyr. Enhanced contribution of wind-blown palygorskite and development of the semi-arid vegetation (Artemisia rich) occurs during the North Atlantic Cold climatic events (Heinrich events). The peculiar clay mineral association and the presence of Argania pollen grains pinpoint Western Morocco as a major source for wind-blown particles during the Heinrich events. Clay mineral and pollen associations indicate the development of semi-desert environment and the intensification of winds favoring dust erosion and transport from Sahara toward the Alboran Sea during the North Atlantic Heinrich events. Quantitative climate reconstructions performed on the ODP976 pollen record have yielded the reconstruction of ombrothermic diagrams for past key periods. They reveal that annual precipitations regime in the west Mediterranean area were rather different during Heinrich events than today with drastic drought during the whole year. As a comparison, the reconstructed Holocene and stadials annual climatic cycles are very similar to present-day distribution, with dry conditions restricted to summertime. During these cold climatic events, the drastic fall in both precipitations and temperatures suggest cold and arid continental conditions in the West Mediterranean area. These regions were suffering from reduced precipitations not only during winter but also during spring and fall usually experiencing wet conditions. Such a major modification, with repetitive cold and dry-conditions in both winter and spring, should have deeply affected the development of temperate forest -sensitive to precipitation amount- and of the Mediterranean forest which lives under warm-dry summer and mild-humid winter conditions. These clay- and pollen-based reconstructions

  10. Fast fluid-flow events within a subduction-related vein system in oceanic eclogite: implications for pore fluid pressure at the plate interface

    NASA Astrophysics Data System (ADS)

    Taetz, Stephan; John, Timm; Bröcker, Michael; Spandler, Carl; Stracke, Andreas

    2017-04-01

    A better understanding of the subduction zone fluid cycle and its mechanical feedback requires in-depth knowledge of how fluids flow within and out of the descending slabs. In order to develop reliable quantitative models of fluid flow, the general relationship between dehydration reactions, fluid pathway formation, and the dimensions and timescales of distinct fluid flow events have to be explored. The high-pressure/low-temperature metamorphic rocks of the Pouébo Eclogite Mélange in New Caledonia provide an excellent opportunity to study the fluid flux in a subduction zone setting. Fluid dynamics are recorded by high-pressure veins that cross-cut eclogite facies mélange blocks from this occurrence. Two types of garnet-quartz-phengite veins can be distinguished. These veins record both synmetamorphic internal fluid release by mineral breakdown reactions (type I veins) as well as infiltration of an external fluid (type II veins) and the associated formation of a reaction halo. The overall dehydration, fluid accumulation and fluid migration documented by the type I veins occurred on a timescale of 10^5-106 years that is mainly given by the geometry and convergence rate of the subduction system. In order to quantify the timeframe of fluid-rock interaction between the external fluid and the wall-rock, we have applied Li-isotope chronology. A continuous profile was sampled perpendicular to a type II vein including material from the vein, the reaction selvage and the immediate host rock. Additional drill cores were taken from parts of the outcrop that most likely remained completely unaffected by fluid infiltration-induced alteration. Different Li concentrations in the internal and external fluid reservoirs produced a distinct diffusion profile of decreasing Li concentration and increasing δ7Li as the reaction front propagated into the host-rock. Li-chronometric constraints indicate that fluid-rock interaction related to the formation of the type II veins and had

  11. Record-low primary productivity and high plant damage in the Nordic Arctic Region in 2012 caused by multiple weather events and pest outbreaks

    NASA Astrophysics Data System (ADS)

    Bjerke, Jarle W.; Rune Karlsen, Stein; Arild Høgda, Kjell; Malnes, Eirik; Jepsen, Jane U.; Lovibond, Sarah; Vikhamar-Schuler, Dagrun; Tømmervik, Hans

    2014-08-01

    The release of cold temperature constraints on photosynthesis has led to increased productivity (greening) in significant parts (32-39%) of the Arctic, but much of the Arctic shows stable (57-64%) or reduced productivity (browning, <4%). Summer drought and wildfires are the best-documented drivers causing browning of continental areas, but factors dampening the greening effect of more maritime regions have remained elusive. Here we show how multiple anomalous weather events severely affected the terrestrial productivity during one water year (October 2011-September 2012) in a maritime region north of the Arctic Circle, the Nordic Arctic Region, and contributed to the lowest mean vegetation greenness (normalized difference vegetation index) recorded this century. Procedures for field data sampling were designed during or shortly after the events in order to assess both the variability in effects and the maximum effects of the stressors. Outbreaks of insect and fungal pests also contributed to low greenness. Vegetation greenness in 2012 was 6.8% lower than the 2000-11 average and 58% lower in the worst affected areas that were under multiple stressors. These results indicate the importance of events (some being mostly neglected in climate change effect studies and monitoring) for primary productivity in a high-latitude maritime region, and highlight the importance of monitoring plant damage in the field and including frequencies of stress events in models of carbon economy and ecosystem change in the Arctic. Fourteen weather events and anomalies and 32 hypothesized impacts on plant productivity are summarized as an aid for directing future research.

  12. Sea level response to ENSO along the central California coast: How the 1997-1998 event compares with the historic record

    USGS Publications Warehouse

    Ryan, H.F.; Noble, M.

    2002-01-01

    Long-term monthly sea level and sea surface temperature (SST) anomalies from central California show that during winter months, positive anomalies are associated with El Nin??o events and the negative ones with La Nin??a events. There is no significant impact on monthly mean anomalies associated with Pacific decadal oscillations, although there is a tendency for more extreme events and greater variance during positive decadal oscillations. The very strong 1997-1998 El Nin??o was analyzed with respect to the long-term historic record to assess the forcing mechanisms for sea level and SST. Beginning in the spring of 1997, we observed several long-period (> 30days) fluctuations in daily sea level with amplitudes of over 10 cm at San Francisco, California. Fluctuations of poleward long-period alongshore wind stress anomalies (AWSA) are coherent with the sea level anomalies. However, the wind stress cannot entirely account for the observed sea level signals. The sea level fluctuations are also correlated with sea level fluctuations observed further south at Los Angeles and Tumaco, Columbia, which showed a poleward phase propagation of the sea level signal. We suggest that the sea level fluctuations were, to a greater degree, forced by the passage of remotely generated and coastally trapped waves that were generated along the equator and propagated to the north along the west coast of North America. However, both local and remote AWSA can significantly modulate the sea level signals. The arrival of coastally trapped waves began in the spring of 1997, which is earlier than previous strong El Nin??o events such as the 1982-1983 event. Published by Elsevier Science Ltd.

  13. Tephra constraints on Rapid Climate Events (TRACE): precise correlation of marine and ice-core records in the North Atlantic region

    NASA Astrophysics Data System (ADS)

    Davies, Siwan; Abbott, Peter; Bourne, Anna; Cook, Eliza; Griggs, Adam; Meara, Rhian

    2013-04-01

    Little has challenged our understanding of climate change more so than the abruptness with which large-scale shifts in temperature occurred during the last glacial period. Atmospheric temperature jumps occurring within decades over Greenland were closely matched by rapid changes in North Atlantic sea surface temperatures and major re-organisation of the deep ocean circulation. Although these climatic instabilities are well-documented in various proxy records, the causal mechanisms of such short-lived oscillations remain poorly understood, largely due to the dating uncertainties that prevent the integration of different archives. Synchronisation of palaeoclimate records on a common timescale is inherently problematic, and unravelling the lead/lag responses (hence cause and effect) between the Earth's climate components is currently beyond our reach. TRACE - a 5 year project funded by the European Research Council - exploits the use of microscopic traces of volcanic events to precisely correlate the Greenland ice-cores with North Atlantic marine records. Tephrochronology has experienced a considerable step-change in recent years, with invisible layers of volcanic ash traced over much wider geographical regions than previously thought. What is more, recent work has identified new, previously unknown eruptions within both marine and ice-core records - several of which fall close to rapid climatic jumps imprinted in the proxy records. Here we draw upon examples of how these time-lines can be used to constrain the lead/lag responses between the atmospheric and oceanic systems during the last glacial period as well as some of the challenges that arise in the application of tephrochronology. Led by Swansea University, this project involves collaboration with groups at the University of Copenhagen, Aberystwyth University, Bangor University, University of St Andrews, Stockholm University, University of Tromsø and the University of East Anglia.

  14. On-line image analysis of the stromboli volcanic activity recorded by the surveillance camera helps the forecasting of the major eruptive events.

    NASA Astrophysics Data System (ADS)

    Cristaldi, A.; Coltelli, M.; Mangiagli, S.; Pecora, E.

    2003-04-01

    The typical activity of Stromboli consists of intermittent mild explosions lasting a few seconds, which take place at different vents and at variable intervals, the most common time interval being 10-20 minutes. However, the routine activity can be interrupted by more violent, paroxysmal explosions, that eject m-sized scoriaceous bombs and lava blocks to a distance of several hundreds of meters from the craters, endangering the numerous tourists that watch the spectacular activity from the volcano's summit located about two hundreds meters from the active vents. On average, 1-2 paroxysmal explosions occurred per year over the past century, but this statistic may be underestimated in absence of continuous monitoring. For this reason from summer 1996 a remote surveillance camera works on Stromboli recording continuously the volcanic activity. It is located on Pizzo Sopra la Fossa, 100 metres above the crater terrace where are the active vents. Using image analysis we seeks to identify any change of the explosive activity trend that could precede a particular eruptive event, like paroxysmal explosions, fire fountains, lava flows. From the day of the camera installation up to present 12 paroxysmal events and lava flows occurred. The analysis include the counting of the explosions occurred at the different craters and the parameterization in classes of intensity for each explosion on the base of tephra dispersion and kinetics energy. The plot of dissipated energy by each crater versus time shows a cyclic behavior with max and min of explosive activity ranging from a few days to a month. Often the craters show opposite trends so when the activity decreases in a crater, increases in the other. Before every paroxysmal explosions recorded, the crater that produced the event decreased and then stopped its activity from a few days to weeks before. The other crater tried to compensate increasing its activity and when it declined the paroxysmal explosion occurred suddenly at

  15. Are historical pollution events on the Delaware River recorded as geochemical marker horizons in adjacent marsh sediments

    SciTech Connect

    Walsh, R.; Yemane, K. . Dept. of Geology Bryn Mawr Coll., PA . Geology Dept.)

    1993-03-01

    In the last two hundred years of massive population and industrial growth, the Delaware River has been subjected to several minor and major pollutions. For example, as recently as June 1989 the tanker Presidente Rivera spilled an estimated hundred thousand to million gallons of oil into the river. In the Lower Delaware Basin tides affect the river and its tributaries up to a hundred kilometers inland. The freshwater marshes adjacent to the creeks that empty into the Delaware River experience diurnal tidal sedimentation. It is thus expected that the pollutants in the waterway would be transported via the tidal channels into the adjacent wetlands. The high sedimentation rate, clay-rich sediments, accumulation of terrestrial organic matter, and the low energy environments in these marshes should ensure rapid burial which may preserve some of the contaminants transported into the marshes. To test this hypothesis the authors selected a freshwater marsh along the Raccoon Creek just south of Philadelphia in New Jersey, and collected a 2 m core from a relatively undist