Sample records for underlying very-low-frequency rr-interval

  1. The Radio And Very Low Frequency (VLF) Electromagnetic ...

    African Journals Online (AJOL)

    The Radio And Very Low Frequency (VLF) Electromagnetic Response Of A Layered Earth Media With Variable Dielectric Permittivity. ... A radio frequency of 125 KHz and a very low frequency (VLF) of 20 KHz were used in the computations and the field parameters studied over a dimensionless induction number, B. The ...

  2. Effects of very low frequency electromagnetic method (VLFEM) and ...

    African Journals Online (AJOL)

    The study examined the impact of livestock dung on ground water status in the study area. To achieve this, a very low frequency EM survey was conducted; the aim and objective was to detect fractures in the subsurface. VLF data were acquired at 5m intervals along two profiles, with maximum length of 60m in the ...

  3. A lunar far-side very low frequency array (United States)

    Burns, Jack O. (Editor); Duric, Nebojsa (Editor); Johnson, Stewart (Editor); Taylor, G. Jeffrey (Editor)


    Papers were presented to consider very low frequency (VLF) radio astronomical observations from the moon. In part 1, the environment in which a lunar VLF radio array would function is described. Part 2 is a review of previous and proposed low-frequency observatories. The science that could be conducted with a lunar VLF array is described in part 3. The design of a lunar VLF array and site selection criteria are considered, respectively, in parts 4 and 5. Part 6 is a proposal for precursor lunar VLF observations. Finally, part 7 is a summary and statement of conclusions, with suggestions for future science and engineering studies. The workshop concluded with a general consensus on the scientific goals and preliminary design for a lunar VLF array.

  4. Very low frequency noise reduction in orthogonal fluxgate (United States)

    Butta, Mattia; Janosek, Michal


    In this paper we present a simple, cheap and effective method to obtain reduction of very low frequency noise in an orthogonal fluxgate in fundamental mode. This method consists in the application of a layer of silicone over the magnetic core of the sensor filling the whole space inside the pick-up coil. In this way we avoid fast variations of temperature to affect the offset of the sensor (which is very sensitive to temperature changes). Eventually the offset will still drift to the same value, but it will do it slower, thus reducing the component of the noise in the sub-Hz region. Using this method we could simply reduce the noise at 100 mHz from 23 to 8 pT/√Hz, with no additional hardware on the excitation or signal conditioning circuits.

  5. Natural very-low-frequency sferics and headache (United States)

    Vaitl, D.; Propson, N.; Stark, R.; Schienle, A.

      Very-low-frequency (VLF) atmospherics or sferics are pulse-shaped alternating electric and magnetic fields which originate from atmospheric discharges (lightning). The objective of the study was threefold: (i) to analyse numerous parameters characterizing the sferics activity with regard to their suitability for field studies, (ii) to identify meteorological processes related to the sferics activity and (iii) to investigate the possible association of sferics with pain processes in patients suffering from migraine- and tension-type headaches. Over a period of 6 months (July through December) the sferics activity in the area of Giessen (Germany) was recorded. Three sferics parameters were chosen. The number of sferics impulses per day, the variability of the impulse rate during a day and the variability in comparison to the preceding day were correlated with weather processes (thunderstorm, temperature, vapour pressure, barometric pressure, humidity, wind velocity, warm sector). Significant correlations were obtained during the summer months (July, August) but not during the autumn months (October, November, December). During autumn, however, the sferics activity was correlated with the occurrence of migraine-type headaches (r=0.33, Pheadache diary over a period of 6 months (July-December). While the thunderstorm activity was very intense during July and August, no relationship between sferics and migraine was found. In summer, tension-type headaches were associated with meteorological parameters such as temperature (r=0.42, P<0.01) and vapour pressure (r=0.28, P<0.05). Although the sferics activity can explain a small percentage of the variation in migraine occurrence, a direct influence was more likely exerted by visible or otherwise perceptible weather conditions (thunderstorms, humidity, vapour pressure, warm sector, etc.) than by the sferics activity itself.

  6. RR-Interval variance of electrocardiogram for atrial fibrillation detection (United States)

    Nuryani, N.; Solikhah, M.; Nugoho, A. S.; Afdala, A.; Anzihory, E.


    Atrial fibrillation is a serious heart problem originated from the upper chamber of the heart. The common indication of atrial fibrillation is irregularity of R peak-to-R-peak time interval, which is shortly called RR interval. The irregularity could be represented using variance or spread of RR interval. This article presents a system to detect atrial fibrillation using variances. Using clinical data of patients with atrial fibrillation attack, it is shown that the variance of electrocardiographic RR interval are higher during atrial fibrillation, compared to the normal one. Utilizing a simple detection technique and variances of RR intervals, we find a good performance of atrial fibrillation detection.

  7. Algorithm and Software for Landslide Slopes Stability Estimation with Online Very Low Frequency Monitoring (United States)

    Gordeev, V. F.; Kabanov, M. M.; Kapustin, S. N.


    In addition to preliminary surveying, landslide slopes stability estimation problems require online real-time monitoring alerting about potential emergencies. Very low frequency monitoring data provided by geodynamic processes automated control system provides a solution to that problem. Authors describe the software and algorithms implemented for that system, make conclusions on the efficiency of applied solutions and propose options for the further development of online very low frequency monitoring system.

  8. Spectral of electrocardiographic RR intervals to indicate atrial fibrillation (United States)

    Nuryani, Nuryani; Satrio Nugroho, Anto


    Atrial fibrillation is a serious heart diseases, which is associated on the risk of death, and thus an early detection of atrial fibrillation is necessary. We have investigated spectral pattern of electrocardiogram in relation to atrial fibrillation. The utilized feature of electrocardiogram is RR interval. RR interval is the time interval between a two-consecutive R peaks. A series of RR intervals in a time segment is converted to a signal with a frequency domain. The frequency components are investigated to find the components which significantly associate to atrial fibrillation. A segment is defined as atrial fibrillation or normal segments by considering a defined number of atrial fibrillation RR in the segment. Using clinical data of 23 patients with atrial fibrillation, we find that the frequency components could be used to indicate atrial fibrillation.

  9. Heartbeat Classification Using Normalized RR Intervals and Morphological Features

    Directory of Open Access Journals (Sweden)

    Chun-Cheng Lin


    Full Text Available This study developed an automatic heartbeat classification system for identifying normal beats, supraventricular ectopic beats, and ventricular ectopic beats based on normalized RR intervals and morphological features. The proposed heartbeat classification system consists of signal preprocessing, feature extraction, and linear discriminant classification. First, the signal preprocessing removed the high-frequency noise and baseline drift of the original ECG signal. Then the feature extraction derived the normalized RR intervals and two types of morphological features using wavelet analysis and linear prediction modeling. Finally, the linear discriminant classifier combined the extracted features to classify heartbeats. A total of 99,827 heartbeats obtained from the MIT-BIH Arrhythmia Database were divided into three datasets for the training and testing of the optimized heartbeat classification system. The study results demonstrate that the use of the normalized RR interval features greatly improves the positive predictive accuracy of identifying the normal heartbeats and the sensitivity for identifying the supraventricular ectopic heartbeats in comparison with the use of the nonnormalized RR interval features. In addition, the combination of the wavelet and linear prediction morphological features has higher global performance than only using the wavelet features or the linear prediction features.

  10. Repeating Deep Very Low Frequency Earthquakes: An Evidence of Transition Zone between Brittle and Ductile Zone along Plate Boundary (United States)

    Ishihara, Y.; Yamamoto, Y.; Arai, R.


    Recently slow or low frequency seismic and geodetic events are focused under recognition of important role in tectonic process. The most western region of Ryukyu trench, Yaeyama Islands, is very active area of these type events. It has semiannual-like slow slip (Heki, 2008; Nishimura,2014) and very frequent shallow very low frequency earthquakes near trench zone (Ando,2012; Nakamura,2014). Arai identified clear reverse phase discontinuity along plate boundary by air-gun survey, suggesting existence of low velocity layer including fluid. The subducting fluid layer is considered to control slip characteristics. On the other hand, deep low frequency earthquake and tremor observed at south-western Honshu and Shikoku of Japan are not identified well due to lack of high-quality seismic network. A broadband seismic station(ISG/PS) of Pacific21 network is operating in last 20 years that locates on occurrence potential area of low frequency earthquake. We tried to review continuous broadband record, searching low frequency earthquakes. In pilot survey, we found three very low frequency seismic events which are dominant in less than 0.1Hz component and are not listed in earthquake catalogue. Source locates about 50km depth and at transition area between slow slip event and active area of general earthquake along plate boundary. To detect small and/or hidden very low frequency earthquake, we applied matched filter analysis to continuous three components waveform data using pre-reviewed seismogram as template signal. 12 events with high correlation are picked up in last 10 years. Most events have very similar waveform, which means characteristics of repeating deep very low frequency earthquake. The event history of very low frequency earthquake is not related with one of slow slip event in this region. In Yaeyama region, low frequency earthquake, general earthquake and slow slip event occur dividing in space and have apparent

  11. Identification and classification of very low frequency waves on a coral reef flat

    NARCIS (Netherlands)

    Gawehn, M.; van Dongeren, AR; van Rooijen, A.A.; Storlazzi, C.D.; Cheriton, O.M.; Reniers, A.J.H.M.


    Very low frequency (VLF, 0.001–0.005 Hz) waves are important drivers of flooding of low-lying coral reef-islands. In particular, VLF wave resonance is known to drive large wave runup and subsequent overwash. Using a 5 month data set of water levels and waves collected along a cross-reef transect on

  12. Statistical modelling of the differences between successive R-R intervals. (United States)

    Mandrekar, Sumithra J; Nagaraja, Haikady N; Berntson, Gary G


    Understanding the behaviour of R-R interval data and its successive differences is critical to the dynamics of cardiac control. Several time domain measures that quantify R-R interval variability have important clinical significance in terms of risk stratification and evaluating the effectiveness of treatment procedures. The present approach at examining the distributions of successive beat-to-beat differences of R-R interval data from different populations and under different conditions (baseline and reaction times) provides a valuable insight into their previously unexplored distributional properties. In particular, our analysis reveals that the successive differences have non-normal statistical distributions (a contradiction to the commonly used assumption of normality), and the absolute successive R-R interval differences approximately follows a Weibull distribution. As an illustration of the utility of this approach, we explore the statistical properties of the time domain measure: root mean square successive difference, study the association between the Weibull scale parameter estimate and respiratory sinus arrhythmia, and propose improvements in artifact detection algorithms. Copyright 2004 John Wiley & Sons, Ltd.

  13. Identification and classification of very low frequency waves on a coral reef flat (United States)

    Gawehn, Matthijs; van Dongeran, Ap; van Rooijen, Arnold; Storlazzi, Curt; Cheriton, Olivia; Reniers, Ad


    Very low frequency (VLF, 0.001–0.005 Hz) waves are important drivers of flooding of low-lying coral reef-islands. In particular, VLF wave resonance is known to drive large wave runup and subsequent overwash. Using a 5 month data set of water levels and waves collected along a cross-reef transect on Roi-Namur Island in the Republic of the Marshall Islands, the observed VLF motions were categorized into four different classes: (1) resonant, (2) (nonresonant) standing, (3) progressive-growing, and (4) progressive-dissipative waves. Each VLF class is set by the reef flat water depth and, in the case of resonance, the incident-band offshore wave period. Using an improved method to identify VLF wave resonance, we find that VLF wave resonance caused prolonged (∼0.5–6.0 h), large-amplitude water surface oscillations at the inner reef flat ranging in wave height from 0.14 to 0.83 m. It was induced by relatively long-period, grouped, incident-band waves, and occurred under both storm and nonstorm conditions. Moreover, observed resonant VLF waves had nonlinear, bore-like wave shapes, which likely have a larger impact on the shoreline than regular, sinusoidal waveforms. As an alternative technique to the commonly used Fast Fourier Transformation, we propose the Hilbert-Huang Transformation that is more computationally expensive but can capture the wave shape more accurately. This research demonstrates that understanding VLF waves on reef flats is important for evaluating coastal flooding hazards.

  14. Identification of atrial fibrillation using electrocardiographic RR-interval difference (United States)

    Eliana, M.; Nuryani, N.


    Automated detection of atrial fibrillation (AF) is an interesting topic. It is an account of very dangerous, not only as a trigger of embolic stroke, but it’s also related to some else chronical disease. In this study, we analyse the presence of AF by determining irregularities of RR-interval. We utilize the interval comparison to measure the degree of irregularities of RR-interval in a defined segment. The series of RR-interval is segmented with the length of 10 of them. In this study, we use interval comparison for the method. We were comparing all of the intervals there each other. Then we put the threshold to define the low difference and high difference (δ). A segment is defined as AF or Normal Sinus by the number of high δ, so we put the tolerance (β) of high δ there. We have used this method to test the 23 patients data from MIT-BIH. Using the approach and the clinical data we find accuracy, sensitivity, and specificity of 84.98%, 91.99%, and 77.85% respectively.

  15. Temporal Activity Modulation of Deep Very Low Frequency Earthquakes in Shikoku, Southwest Japan (United States)

    Baba, Satoru; Takeo, Akiko; Obara, Kazushige; Kato, Aitaro; Maeda, Takuto; Matsuzawa, Takanori


    We investigated long-term changes in the activity of deep very low frequency earthquakes (VLFEs) in western Shikoku, southwest part of the Nankai subduction zone in Japan for 13 years by the matched-filter technique. VLFE activity is expected to be a proxy of interplate slips. In the Bungo channel, where long-term slow slip events (SSEs) occurred frequently, the cumulative number of detected VLFEs increased rapidly in 2010 and 2014, which were modulated by long-term SSEs. In the neighboring inland region near the Bungo channel, the cumulative number increased steeply every 6 months. This stepwise change was accompanied by episodic tremors and slips. Deep VLFE activity in western Shikoku has been low since the latter half of 2014. This decade-scale quiescence may be attributed to the change in interplate coupling strength in the Nankai subduction zone.

  16. ISII-II satellite observations during Siple Station very-low-frequency wave-injection experiments

    International Nuclear Information System (INIS)

    Bell, T.F.; Katsufrakis, J.P.


    One of the critical scientific objectives of space plasma physics is to understand the processes that couple distinct parts of the Earth's plasma environment, such as the solar wind, magnetosphere, ionosphere, and upper atmosphere. An important source of coupling between the magnetosphere, ionosphere, and upper atmosphere is the flux of energetic particles which are precipitated from the Earth's radiation belts through interactions with both natural and manmade very-low-frequency (VLE) waves. One of the goals of this study is to understand a newly discovered phenomenon in which high-amplitude electrostatic waves are stimulated by electromagnetic VLF whistler-mode waves propagating at low altitudes (less than 8,000 kilometers) (Bell and Ngo in press a). This phenomenon is very common at all latitudes, and theoretical models (Bell and Ngo in press b) indicate that the electrostatic waves are stimulated when the input electromagnetic waves scatter from small scale (less than 100 meters) magnetic-field-aligned plasma density irregularities. It is believed that the stimulated electrostatic waves produce enhanced pitch angle scattering of energetic radiation belt particles, resulting in enhanced particle precipitation. The precipitated flux produces plasma density enhancements in the ionosphere, and upward diffusion of thermal plasma from the regions of enhanced ionospheric plasma density creates additional magnetic-field-aligned plasma density irregularities in the magnetosphere

  17. Phase measurements of very-low-frequency signals from the magnetosphere

    International Nuclear Information System (INIS)

    Paschal, E.V.


    The usual methods of spectrum analysis applied to analog tape recordings of very low frequency (VLF) signals extract only magnitude information and ignore phase information. A digital signal-processing system using a recorded constant-frequency pilot tone was developed that can correct tape errors due to wow and flutter, and reconstruct the signal phases. Frequency shifts are corrected during analysis by interpolating between spectral points in the windowed Fourier transform, and the output phases of the synthesized filters are corrected for timing errors. Having signal-component phases as well as magnitudes doubles the available information. Whistler-mode signals from the VLF transmitter at Siple Station, Antarctica, were analyzed as received at Roberval, Quebec. The phase of a non-growing signal is found to give a less-noisy measure of duct motion than Doppler frequency shift, with improved time resolution. Correlations are seen between variations in the whistler-mode phase delay and the earth's magnetic field component D. They are interpreted as Pc 2 micropulsation transients, short compared to the length of the field line, which propagate from equator to ground as Alfven waves


    Directory of Open Access Journals (Sweden)



    Full Text Available Studies of groundwater consist in data acquisition, their processing and interpretation. In areas of interest hydrogeological is assumed that there is a network of wells drilled. This network provides a first in the hydrogeological information. Electromagnetic (EM mapping through the use of such areas, using data obtained from existing network of wells drilled, calibration and confirmation. Measurements using the EM can highlight the existence of several layers with different characteristics: clay, limestone, sand, etc. Studies of groundwater interpretation are used for developing a regional hydrogeologic model. The application of electromagnetic techniques for measuring soil resistivity or conductivity has been known for a long time. Conductivity is preferable in inductive techniques, as instrumentation readings are generally directly proportional to conductivity and inversely proportional to resistivity. The operating principle of this method is: a Tx coil transmitter, supplied with alternating current at an audio frequency, is placed on the ground. An Rx coil receiver is located at a short distance, s, away from the Tx coil. The magnetic field varies in time and the Tx coil induces very small currents in the ground. These currents generate a secondary magnetic field, Hs, which is sensed by the Rx receiver coil, together, with primary magnetic field Hp. The ratio of the secondary field, Hs, to the primary magnetic field, Hp, (Hs/Hp is directly proportional to terrain conductivity. Measuring this ratio, it is possible to construct a device which measures the terrain conductivity by contactless, direct-reading electromagnetic technique (linear meter. This technique for measuring conductivity by electromagnetic induction, using Very Low Frequency (VLF, is a non-intrusive, non-destructive sampling method. The measurements can be done quickly and are not expensive. The Electromagnetic induction technology was originally developed for the mining

  19. Locating Very-Low-Frequency Earthquakes in the San Andreas Fault. (United States)

    Peña-Castro, A. F.; Harrington, R. M.; Cochran, E. S.


    The portion of tectonic fault where rheological properties transtition from brittle to ductile hosts a variety of seismic signals suggesting a range of slip velocities. In subduction zones, the two dominantly observed seismic signals include very-low frequency earthquakes ( VLFEs), and low-frequency earthquakes (LFEs) or tectonic tremor. Tremor and LFE are also commonly observed in transform faults, however, VLFEs have been reported dominantly in subduction zone environments. Here we show some of the first known observations of VLFEs occurring on a plate boundary transform fault, the San Andreas Fault (SAF) between the Cholame-Parkfield segment in California. We detect VLFEs using both permanent and temporary stations in 2010-2011 within approximately 70 km of Cholame, California. We search continous waveforms filtered from 0.02-0.05 Hz, and remove time windows containing teleseismic events and local earthquakes, as identified in the global Centroid Moment Tensor (CMT) and the Northern California Seismic Network (NCSN) catalog. We estimate the VLFE locations by converting the signal into envelopes, and cross-correlating them for phase-picking, similar to procedures used for locating tectonic tremor. We first perform epicentral location using a grid search method and estimate a hypocenter location using Hypoinverse and a shear-wave velocity model when the epicenter is located close to the SAF trace. We account for the velocity contrast across the fault using separate 1D velocity models for stations on each side. Estimated hypocentral VLFE depths are similar to tremor catalog depths ( 15-30 km). Only a few VLFEs produced robust hypocentral locations, presumably due to the difficulty in picking accurate phase arrivals with such a low-frequency signal. However, for events for which no location could be obtained, the moveout of phase arrivals across the stations were similar in character, suggesting that other observed VLFEs occurred in close proximity.

  20. Altered relationship between R-R interval and R-R interval variability in endurance athletes with overtraining syndrome. (United States)

    Kiviniemi, A M; Tulppo, M P; Hautala, A J; Vanninen, E; Uusitalo, A L T


    Autonomic dysfunction decreases within-subject correlation between R-R interval length (RRi) and vagally mediated RRi variability in cardiac disease. We tested the hypothesis that overtraining syndrome (OTS) may also weaken this relationship. Nine OTS and 10 control endurance athletes underwent 24-h electrocardiogram monitoring, which was repeated in eight OTS and nine control athletes after 6 months, when two OTS athletes still had symptoms of OTS. The power of high-frequency (HF) oscillations of RRi was analyzed in 5-min epochs over the whole recording. Quadratic regression was performed between 5-min values of RRi and log-transformed (ln) HF to obtain R(2) for each recording. The relationship between RRi and HFln was higher in the OTS athletes than controls [R(2): 0.87 (90% confidence interval, CI: 0.84-0.89) vs 0.78 (90% CI: 0.72-0.84); P = 0.034; effect size = 1.22]. Large decrease in R(2) was observed in six recovered OTS athletes after 6 months follow-up [ΔR(2): -0.12 (90% CI: -0.25-0.01); P = 0.11; effect size = 1.44] with no changes in the controls. Mean values of RRi and its variability did not differ between the groups. The within-subject correlation between RRi and vagally mediated RRi variability was stronger in endurance athletes with OTS compared with controls. The present findings may improve the detection of OTS and recovery from OTS in endurance athletes. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Very low frequency radio signatures of transient luminous events above thunderstorms (United States)

    Marshall, Robert Andrew

    Lightning discharges emit intense optical and acoustic energy, in the form of lightning and thunder, respectively, but a large amount of energy is emitted as radio-frequency electromagnetic pulses (EMP). These pulses can be detected thousands of kilometers away, thanks to efficient propagation in the waveguide formed by the conducting Earth and the overlying ionosphere. In addition, intense discharges interact with the overlying ionosphere at 80-100 km altitude. The EMP-ionosphere interaction is directly observed in one manifestation as the bright transient optical emissions known as "elves", but in addition, the interaction can directly modify the free electron density in the nighttime lower ionosphere. Modifications of the ionospheric electron density can be detected via subionospheric Very Low Frequency (VLF) remote sensing. In this method, coherent signals from powerful VLF transmitters, built for submarine communication and operated by the Navy, are monitored and their amplitude and phase are tracked in time. The variations of these signais are used to sense ionospheric modifications through rapid changes in the received amplitude and/or phase when the transmitted signal propagates through an ionospheric perturbation. When these perturbations are caused by lightning, they are known as "Early VLF" perturbations, due to the negligible delay between the lightning discharge and the appearance of the VLF signal change, whereas lightning-induced electron precipitation (LEP) events have a delay of 1--2 seconds. In this work, correlations between VLF signatures and optical events are used to show that these Early VLF events may be the signature of ionospheric modification by in-cloud (IC) lightning discharges. While the more impressive cloud-to-ground (CG) lightning discharges are more commonly observed and better understood, they are outnumbered in occurrence 3:1 by IC discharges, whose effects may be relatively stronger in the overlying ionosphere. We use a 3D time

  2. Delineation of Gold Mineralization Zone using Resistivity and Very Low Frequency Electromagnetic Methods around, North Singhbhum Mobile Belt, India. (United States)

    Upadhyay, A.; Panda, K. P.; Singh, A.; Sharma, S. P.


    The results of electrical resistivity and VLF electromagnetic surveys are presented in this study to delineate the suitable geological structure associated with gold mineralization near Lawa Village (Seraikela-Kharsawan, Jharkhand), India. The area under observation lies in North Singhbhum Mobile Belt (NSMB) which is bounded by Chotanagpur Gneiss Complex in north and Archean Singhbhum Craton in the south. Shear zone of the study area, trending E-W, is mainly associated with Cu-U mineralization which is also associated with gold. Previous geological studies have revealed that this region can be a potential site for gold prospects within NSMB. A comprehensive electrical resistivity imaging and very low frequency surveys have been performed around Lawa village to outline appropriate conducting zones, with their lateral extension and depth extent, which may be associated with gold mineralization. Resistivity survey done using Dipole-Dipole multi-electrode array reveals multiple zones of mineralization separated by variable distances. The VLF data in the current study was tainted by non-stationary and non-linear noises which cannot be eliminated by standard filtering techniques. Therefore to restore signals with significant geologic information empirical mode decomposition (EMD) technique was used. The noise free data obtained was then processed using Fast Imaging technique to obtain apparent current density pseudo-sections for interpretation. Interpretation and analysis of results from each investigating survey demonstrate a steeply dipping conductor with E-W strike direction along the shear zone. These conductive zones are characterized by low resistivity and high current density values.

  3. Very-low-frequency resistivity, self-potential and ground temperature surveys on Taal volcano (Philippines): Implications for future activity (United States)

    Zlotnicki, J.; Vargemezis, G.; Johnston, M. J. S.; Sasai, Y.; Reniva, P.; Alanis, P.


    Taal volcano is one of the most dangerous volcanoes in the Philippines. Thirty-three eruptions have occurred through historical time with several exhibiting cataclysmic phases. Most recent eruptions are confined to Volcano Island located within the prehistoric Taal collapse caldera that is now filled by Taal Lake. The last eruptive activity from 1965 to 1977 took place from Mt. Tabaro, about 2 km to the southwest of the Main Crater center. Since this time, episodes of seismic activity, ground deformation, gas release, surface fissuring, fumarole activity and temperature changes are recorded periodically around the main crater, but no major eruption has occurred. This period of quiescence is the third longest period without eruptive activity since 1572. In March 2010, a campaign based on Very-Low-Frequency (VLF) resistivity surveys together with repeated surveys of self-potential, ground temperature and fissure activity was intensified and the results compared to a large-scale Electrical Resistivity Tomography experiment. This work fortunately occurred before, within and after a new seismovolcanic crisis from late April 2010 to March 2011. The joint analysis of these new data, together with results from previous magnetotelluric soundings, allows a better description of the electrical resistivity and crustal structure beneath the Main Crater down to a depth of several kilometers. No indication of growth of the two geothermal areas located on both sides of the northern crater rim was apparent from 2005 to March 2010. These areas appear controlled by active fissures, opened during the 1992 and 1994 crises, that dip downward towards the core of the hydrothermal system located at about 2.5 km depth beneath the crater. Older mineralized fissures at lower elevations to the North of the geothermal areas also dip downward under the crater. Repeated self-potential and ground temperature surveys completed between 2005 and 2015 show new geothermal and hydrothermal activity in

  4. Ventricular cycle length characteristics estimative of prolonged RR interval during atrial fibrillation. (United States)

    Ciaccio, Edward J; Biviano, Angelo B; Gambhir, Alok; Einstein, Andrew J; Garan, Hasan


    When atrial fibrillation (AF) is incessant, imaging during a prolonged ventricular RR interval may improve image quality. It was hypothesized that long RR intervals could be predicted from preceding RR values. From the PhysioNet database, electrocardiogram RR intervals were obtained from 74 persistent AF patients. An RR interval lengthened by at least 250 ms beyond the immediately preceding RR interval (termed T0 and T1, respectively) was considered prolonged. A two-parameter scatterplot was used to predict the occurrence of a prolonged interval T0. The scatterplot parameters were: (1) RR variability (RRv) estimated as the average second derivative from 10 previous pairs of RR differences, T13-T2, and (2) Tm-T1, the difference between Tm, the mean from T13 to T2, and T1. For each patient, scatterplots were constructed using preliminary data from the first hour. The ranges of parameters 1 and 2 were adjusted to maximize the proportion of prolonged RR intervals within range. These constraints were used for prediction of prolonged RR in test data collected during the second hour. The mean prolonged event was 1.0 seconds in duration. Actual prolonged events were identified with a mean positive predictive value (PPV) of 80% in the test set. PPV was >80% in 36 of 74 patients. An average of 10.8 prolonged RR intervals per 60 minutes was correctly identified. A method was developed to predict prolonged RR intervals using two parameters and prior statistical sampling for each patient. This or similar methodology may help improve cardiac imaging in many longstanding persistent AF patients. ©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.

  5. Land and Undersea Field Testing of Very Low Frequency RF Antennas and Loop Transceivers (United States)


    and extrapolated range. Similar capabilities of the SSC Pacific-built loop transceiver system were also determined. The report presents the mechanical ... shot of the Engineering tab. Test Commands sends command codes to the unit under control. Test Data sends text to other WFS units. The Text Figure 3. Screen shot of the Engineering tab. Test Commands sends command codes to the unit under control. Test Data sends text to other WFS

  6. Estimation of Existence Geothermal Manifestation Using Very Low Frequency (VLF) Method in the PagerkandangVulcanic, Dieng, Central Java (United States)

    Wulandari, Asri; Asti Anggari, Ega; Dwiasih, Novi; Suyanto, Imam


    Very Low Frequency (VLF) measurement has been done at Pagerkandang Volcanic, Dieng Volcanic Complex (DVC) to examine the possible existence of conductive zones that related with geothermal manifestation. VLF – EM survey used tilt mode with T-VLF BRGM Iris Instrument operated with two frequencies, they are 22200 Hz from Japan (JJI) and 19800 Hz from Australia (NWC). There are five lines with distance between lines is 50 m, and distance between measure points is 20 m. The parameters measured from VLF method are tilt angle (%) and elliptisity (%). Data processed by tilt angle value with fraser and Karous – Hjelt filter used WinVLF program. Karous – Hjelt filter resulted current density contour to estimate lateral location from conductive and resistive zones. The conductive zone is interpreted as the area which have high current density value. This area located at eastern dan western of Pagerkandang Volcanic. The conductive zone related to geothermal manifestation as like as fumarol that appeared because presenced of normal fault. Whereas the resistive zone is interpreted as the area which have low current density value. This area spread almost in the middle of the Pagerkandang Volcanic. The resistive zone was caused by the high weathering in claystone.

  7. Parametric excitation of very low frequency (VLF) electromagnetic whistler waves and interaction with energetic electrons in radiation belt (United States)

    Sotnikov, V.; Kim, T.; Caplinger, J.; Main, D.; Mishin, E.; Gershenzon, N.; Genoni, T.; Paraschiv, I.; Rose, D.


    The concept of a parametric antenna in ionospheric plasma is analyzed. Such antennas are capable of exciting electromagnetic radiation fields, specifically the creation of whistler waves generated at the very low frequency (VLF) range, which are also capable of propagating large distances away from the source region. The mechanism of whistler wave generation is considered a parametric interaction of quasi-electrostatic whistler waves (also known as low oblique resonance (LOR) oscillations) excited by a conventional loop antenna. The interaction of LOR waves with quasi-neutral density perturbations in the near field of an antenna gives rise to electromagnetic whistler waves on combination frequencies. It is shown in this work that the amplitude of these waves can considerably exceed the amplitude of whistler waves directly excited by a loop. Additionally, particle-in-cell simulations, which demonstrate the excitation and spatial structure of VLF waves excited by a loop antenna, are presented. Possible applications including the wave-particle interactions to mitigate performance anomalies of low Earth orbit satellites, active space experiments, communication via VLF waves, and modification experiments in the ionosphere will be discussed.

  8. Modeling of temporal variation of very low frequency radio waves over long paths as observed from Indian Antarctic stations (United States)

    Sasmal, Sudipta; Basak, Tamal; Chakraborty, Suman; Palit, Sourav; Chakrabarti, Sandip K.


    Characteristics of very low frequency (VLF) signal depends on solar illumination across the propagation path. For a long path, solar zenith angle varies widely over the path and this has a significant influence on the propagation characteristics. To study the effect, Indian Centre for Space Physics participated in the 27th and 35th Scientific Expedition to Antarctica. VLF signals transmitted from the transmitters, namely, VTX (18.2 kHz), Vijayanarayanam, India, and NWC (19.8 kHz), North West Cape, Australia, were recorded simultaneously at Indian permanent stations Maitri and Bharati having respective geographic coordinates 70.75°S, 11.67°E, and 69.4°S, 76.17°E. A very stable diurnal variation of the signal has been obtained from both the stations. We reproduced the signal variations of VLF signal using solar zenith angle model coupled with long wavelength propagation capability (LWPC) code. We divided the whole path into several segments and computed the solar zenith angle (χ) profile. We assumed a linear relationship between the Wait's exponential model parameters effective reflection height (h'), steepness parameter (β), and solar zenith angle. The h' and β values were later used in the LWPC code to obtain the VLF signal amplitude at a particular time. The same procedure was repeated to obtain the whole day signal. Nature of the whole day signal variation from the theoretical modeling is also found to match with our observation to some extent.

  9. The variable heart: High frequency and very low frequency correlates of depressive symptoms in children and adolescents. (United States)

    Blood, Julia D; Wu, Jia; Chaplin, Tara M; Hommer, Rebecca; Vazquez, Lauren; Rutherford, Helena J V; Mayes, Linda C; Crowley, Michael J


    Work examining the link between lower heart rate variability (HRV) and depression in children and adolescents is lacking, especially in light of the physiological changes that occur during pubertal development. We investigated the association between spectral measures of resting HRV and depressive symptoms among 127 children and adolescents, ages 10-17. Using spectral analysis, we evaluated (1) the association between relative high frequency (HF) HRV and depressive symptoms; (2) the predictive power of relative HF HRV for depressive symptoms in the context of relative low frequency (LF) and relative very low frequency (VLF) HRV; and (3) the relationship between relative HF, LF, and VLF band activity, age and pubertal maturation. Consistent with previous work, results revealed that relative HF HRV was negatively associated with self-reported depressive symptoms. As well, relative VLF HRV was positively associated with depressive symptoms. Regression analyses revealed that relative HF HRV and relative VLF HRV significantly predicted self-report depressive symptoms while controlling for age, sex and pubertal maturation, with relative VLF HRV emerging as the strongest indicator of depressive symptoms. Developmental findings also emerged. Age and pubertal maturation were negatively associated with relative HF HRV and positively correlated with relative VLF HRV. Results provide support for the relationship between HRV and depression and suggest that both HF and VLF HRV are relevant to depression symptom severity. Findings also reinforce the importance of considering pubertal development when investigating HRV-depression associations in children and adolescents. Influences on cardiac control including physical activity levels and exercise patterns could be controlled in future work. Our data speak to a depressive symptom dimension and relative spectral power HRV. Thus, we cannot make strong claims about relative spectral power HRV and clinical depression. Copyright

  10. Distribution of very low frequency earthquakes in the Nankai accretionary prism influenced by a subducting-ridge (United States)

    Toh, Akiko; Obana, Koichiro; Araki, Eiichiro


    We investigated the distribution of very low frequency earthquakes (VLFEs) that occurred in the shallow accretionary prism of the eastern Nankai trough during one week of VLFE activity in October 2015. They were recorded very close from the sources by an array of broadband ocean bottom seismometers (BBOBSs) equipped in Dense Oceanfloor Network system for Earthquakes and Tsunamis 1 (DONET1). The locations of VLFEs estimated using a conventional envelope correlation method appeared to have a large scatter, likely due to effects of 3D structures near the seafloor and/or sources that the method could not handle properly. Therefore, we assessed their relative locations by introducing a hierarchal clustering analysis based on patterns of relative peak times of envelopes within the array measured for each VLFE. The results suggest that, in the northeastern side of the network, all the detected VLFEs occur 30-40 km landward of the trench axis, near the intersection of a splay fault with the seafloor. Some likely occurred along the splay fault. On the other hand, many VLFEs occur closer to the trench axis in the southwestern side, likely along the plate boundary, and the VLFE activity in the shallow splay fault appears less intense, compared to the northeastern side. Although this could be a snap-shot of activity that becomes more uniform over longer-term, the obtained distribution can be reasonably explained by the change in shear stresses and pore pressures caused by a subducting-ridge below the northeastern side of DONET1. The change in stress state along the strike of the plate boundary, inferred from the obtained VLFE distribution, should be an important indicator of the strain release pattern and localised variations in the tsunamigenic potential of this region.

  11. Attention-induced deactivations in very low frequency EEG oscillations: differential localisation according to ADHD symptom status.

    Directory of Open Access Journals (Sweden)

    Samantha J Broyd

    Full Text Available BACKGROUND: The default-mode network (DMN is characterised by coherent very low frequency (VLF brain oscillations. The cognitive significance of this VLF profile remains unclear, partly because of the temporally constrained nature of the blood oxygen-level dependent (BOLD signal. Previously we have identified a VLF EEG network of scalp locations that shares many features of the DMN. Here we explore the intracranial sources of VLF EEG and examine their overlap with the DMN in adults with high and low ADHD ratings. METHODOLOGY/PRINCIPAL FINDINGS: DC-EEG was recorded using an equidistant 66 channel electrode montage in 25 adult participants with high- and 25 participants with low-ratings of ADHD symptoms during a rest condition and an attention demanding Eriksen task. VLF EEG power was calculated in the VLF band (0.02 to 0.2 Hz for the rest and task condition and compared for high and low ADHD participants. sLORETA was used to identify brain sources associated with the attention-induced deactivation of VLF EEG power, and to examine these sources in relation to ADHD symptoms. There was significant deactivation of VLF EEG power between the rest and task condition for the whole sample. Using s-LORETA the sources of this deactivation were localised to medial prefrontal regions, posterior cingulate cortex/precuneus and temporal regions. However, deactivation sources were different for high and low ADHD groups: In the low ADHD group attention-induced VLF EEG deactivation was most significant in medial prefrontal regions while for the high ADHD group this deactivation was predominantly localised to the temporal lobes. CONCLUSIONS/SIGNIFICANCE: Attention-induced VLF EEG deactivations have intracranial sources that appear to overlap with those of the DMN. Furthermore, these seem to be related to ADHD symptom status, with high ADHD adults failing to significantly deactivate medial prefrontal regions while at the same time showing significant attenuation of

  12. Effect of oscillatory breathing on the variability of the RR Intervals and its prognostic importance in individuals with left ventricular global systolic dysfunction

    Directory of Open Access Journals (Sweden)

    Barbosa Paulo Roberto Benchimol


    Full Text Available OBJECTIVE: To assess the effect of the oscillatory breathing on the variability of RR intervals (VRR and on prognostic significance after one year follow-up in subjects with left ventricular global systolic dysfunction. METHODS: We studied 76 subjects, whose age ranged from 40 to 80 years, paired for age and gender, divided into two groups: group I - 34 healthy subjects; group II - 42 subjects with left ventricular global systolic dysfunction (ejection fraction < 0.40. The ECG signals were acquired during 600s in supine position, and analyzed the variation of the thoracic amplitude and the VRR. Clinical and V-RR variables were applied into a logistic multivariate model to foretell survival after one year follow-up. RESULTS: Oscillatory breathing was detected in 35.7% of subjects in vigil state of group II, with a concentration of the spectral power in the very low frequency band, and was independent of the presence of diabetes, functional class, ejection fraction, cause of ventricular dysfunction and survival after one year follow-up. In the logistic regression model, ejection fraction was the only independent variable to predict survival. CONCLUSION: 1 Oscillatory breathing pattern is frequent during wakefulness in the left ventricular global systolic dysfunction and concentrates spectral power in the very low band of V-RR; 2 it does not relate to severity and cause of left ventricular dysfunction; 3 ejection fraction is the only independent predictive variable for survival in this group of subjects.

  13. Using Complexity Metrics With R-R Intervals and BPM Heart Rate Measures

    DEFF Research Database (Denmark)

    Wallot, Sebastian; Fusaroli, Riccardo; Tylén, Kristian


    of interpersonal coordination. However, there is no consensus about which measurements and analytical tools are most appropriate in mapping the temporal dynamics of heart rate and quite different metrics are reported in the literature. As complexity metrics of heart rate variability depend critically...... dynamics, but their power to do so critically depends on the type data that is employed: While R-R intervals are very susceptible to nonlinear analyses, the success of nonlinear methods for BPM data critically depends on their construction. Generally, ‘oversampled’ BPM time-series can be recommended...

  14. Properties of Asymmetric Detrended Fluctuation Analysis in the time series of RR intervals (United States)

    Piskorski, J.; Kosmider, M.; Mieszkowski, D.; Krauze, T.; Wykretowicz, A.; Guzik, P.


    Heart rate asymmetry is a phenomenon by which the accelerations and decelerations of heart rate behave differently, and this difference is consistent and unidirectional, i.e. in most of the analyzed recordings the inequalities have the same directions. So far, it has been established for variance and runs based types of descriptors of RR intervals time series. In this paper we apply the newly developed method of Asymmetric Detrended Fluctuation Analysis, which so far has mainly been used with economic time series, to the set of 420 stationary 30 min time series of RR intervals from young, healthy individuals aged between 20 and 40. This asymmetric approach introduces separate scaling exponents for rising and falling trends. We systematically study the presence of asymmetry in both global and local versions of this method. In this study global means "applying to the whole time series" and local means "applying to windows jumping along the recording". It is found that the correlation structure of the fluctuations left over after detrending in physiological time series shows strong asymmetric features in both magnitude, with α+ physiological data after shuffling or with a group of symmetric synthetic time series.

  15. The effects of concurrent use of vitamin A and very low frequency electromagnetic field (50Hz) on limb bud development in chick embryo


    Javad Baharara; Masomeh Saboori


    Background: Electromagnetic fields depending on the intensity and frequency have variety effects on living organisms. Vitamin A has an important role on the growth of living organisms. In this study, the effects of concurrent use of vitamin A and very low frequency electromagnetic field on the growth of limb bud of chick embryo have been investigated. Materials and Method: This experimental laboratory study was performed on 30 eggs with Gallus gallus fertilized race. The eggs were randomly di...

  16. R-R interval variations influence the degree of mitral regurgitation in dogs with myxomatous mitral valve disease

    DEFF Research Database (Denmark)

    Reimann, M. J.; Moller, J. E.; Haggstrom, J.


    of congestive heart failure due to MMVD. The severity of MR was evaluated in apical four-chamber view using colour Doppler flow mapping (maximum % of the left atrium area) and colour Doppler M-mode (duration in ms). The influence of the ratio between present and preceding R-R interval on MR severity......Mitral regurgitation (MR) due to myxomatous mitral valve disease (MMVD) is a frequent finding in Cavalier King Charles Spaniels (CKCSs). Sinus arrhythmia and atrial premature complexes leading to R-R interval variations occur in dogs. The aim of the study was to evaluate whether the duration...... of the RR interval immediately influences the degree of MR assessed by echocardiography in dogs. Clinical examination including echocardiography was performed in 103 privately-owned dogs: 16 control Beagles, 70 CKCSs with different degree of MR and 17 dogs of different breeds with clinical signs...

  17. The effects of concurrent use of vitamin A and very low frequency electromagnetic field (50Hz on limb bud development in chick embryo

    Directory of Open Access Journals (Sweden)

    Javad Baharara


    Full Text Available Background: Electromagnetic fields depending on the intensity and frequency have variety effects on living organisms. Vitamin A has an important role on the growth of living organisms. In this study, the effects of concurrent use of vitamin A and very low frequency electromagnetic field on the growth of limb bud of chick embryo have been investigated. Materials and Method: This experimental laboratory study was performed on 30 eggs with Gallus gallus fertilized race. The eggs were randomly divided into three equal groups including control, laboratory control and experimental. The samples of experimental group were treated with vitamin A 56 hours after incubation (1 IU. Then eggs were placed in active electromagnetic waves generator machine with 50 HZ frequency and 50 G intensity for 3 hours. On the twelfth day of incubation, embryos were removed from their eggs and measured embryo weight and total length of embryo hindlimb. Then embryos were prepared for histological studies with microscope using measurement software "Image J" in microscope sections at length of tibia, length of ontogenesis zone and also counting of chondrocytes of epiphysis and diaphysis. The resulting data were analyzed with SPSS-15.Results: The results show a significant decrease in the average of embryo weight, total length of embryo limb, length of tibia, average of chondrocyte zones of epiphysis and diaphysis and average length of osteogenesis zone (p=0.001.Conclusion: Based on this Study we conclude that concurrent use of vitamin A and very low frequency electromagnetic field has a delayed effect on development of chick embryo and it causes decreased embryo weight, limb length and accumulation of chondrocyte

  18. Analysis of Fluctuations of Electron Density in the D-region During the 2017 Solar Eclipse using a Very Low Frequency Receiver (United States)

    Hernandez, E.; Mathur, S.; Fenton, A.; Behrend, C. C.; Bering, E., III


    As part of the Undergraduate Student Instrumentation Project (USIP) at the University of Houston, multiple Very Low Frequency (VLF) Radio Receivers will be set up during the 2017 solar eclipse. They will be taking data from Omaha, Nebraska and Casper, Wyoming. The receiver, using an air loop antenna, will record magnetic field fluctuations caused by VLF waves. The purpose of this experiment is to study the effects of the sudden change in electromagnetic radiation from the sun on the D-region of the ionosphere. VLF waves were chosen for measurement because naturally occurring VLF waves propagate through the Earth-ionosphere waveguide, which can be used to remotely observe the ionosphere. The D-region reduces the energy in propagating waves due to absorption. This means that any fluctuations in the D-region are inversely correlated to the strength of VLF waves being received. The experiment will focus on receiving waves transmitted from specific stations that are on the other side of totality. The amplitude and phase of the received waves will be measured and analyzed. It is hoped that this experiment will help us gain a better understanding of VLFs from the D-region during the solar eclipse, as well as increasing the overall data available for use by the community.

  19. Hydraulic continuity and biological effects of low strength very low frequency electromagnetic waves: Case of microbial biofilm growth in water treatment. (United States)

    Gérard, Merlin; Noamen, Omri; Evelyne, Gonze; Eric, Valette; Gilles, Cauffet; Marc, Henry


    This study aims to elucidate the interactions between water, subjected to electromagnetic waves of very low frequency (VLF) (kHz) with low strength electromagnetic fields (3.5 mT inside the coils), and the development of microbial biofilms in this exposed water. Experimental results demonstrate that in water exposed to VLF electromagnetic waves, the biomass of biofilm is limited if hydraulic continuity is achieved between the electromagnetic generator and the biofilm media. The measured amount of the biofilm's biomass is approximately a factor two lower for exposed biofilm than the non-exposed biofilm. Measurements of electromagnetic fields in the air and simulations exhibit very low intensities of fields (electromagnetic generator. Exposure to electric and magnetic fields of the quoted intensities cannot explain thermal and ionizing effects on the biofilm. A variable electrical potential with a magnitude close to 20 mV was detected in the tank in hydraulic continuity with the electromagnetic generator. The application of quantum field theory may help to explain the observed effects in this case. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Modeling of very low frequency (VLF radio wave signal profile due to solar flares using the GEANT4 Monte Carlo simulation coupled with ionospheric chemistry

    Directory of Open Access Journals (Sweden)

    S. Palit


    Full Text Available X-ray photons emitted during solar flares cause ionization in the lower ionosphere (~60 to 100 km in excess of what is expected to occur due to a quiet sun. Very low frequency (VLF radio wave signals reflected from the D-region of the ionosphere are affected by this excess ionization. In this paper, we reproduce the deviation in VLF signal strength during solar flares by numerical modeling. We use GEANT4 Monte Carlo simulation code to compute the rate of ionization due to a M-class flare and a X-class flare. The output of the simulation is then used in a simplified ionospheric chemistry model to calculate the time variation of electron density at different altitudes in the D-region of the ionosphere. The resulting electron density variation profile is then self-consistently used in the LWPC code to obtain the time variation of the change in VLF signal. We did the modeling of the VLF signal along the NWC (Australia to IERC/ICSP (India propagation path and compared the results with observations. The agreement is found to be very satisfactory.

  1. Association between RR interval and high-frequency heart rate variability acquired during short-term, resting recordings with free and paced breathing

    International Nuclear Information System (INIS)

    Sandercock, Gavin; Gladwell, Valerie; Beneke, Ralph; Dawson, Samantha; Nunan, David; Brodie, David


    High-frequency (HF) oscillations in RR interval from 0.15–0.40 Hz are widely accepted as a measure of cardiac vagal outflow but the HF/RR relationship appears complex, particularly with longer RR intervals. The aim of this study was to evaluate the HF/RR interval relationship during free and paced breathing. HF power and mean RR interval length were recorded in 150 men and 120 women (mean age 34.5 ± 11.4) during 5 min of supine rest with either free or paced (12 cycles min −1 ) breathing. Linear and quadratic models were used to assess the relationship between RR interval and the natural logarithm of HF power (lnHF). The RR interval length at which there was no further increase in lnHF was determined as the deflection point. ANCOVA was used to determine differences in the linear regression slopes for lnHF/RR with paced or free breathing. With free breathing (n = 131), the adjusted R 2 was similar between linear (15.3%) and quadratic (17.5%) fits and saturation of lnHF occurred within the recorded RR interval range (1326 ms). With paced breathing (n = 139), adjusted R 2 values were again similar between linear (22.4%) and quadratic (23.2%) fits. The deflection point was outside the range of recorded RR intervals at 1458 ms. ANCOVA showed a significant difference in the slope of the lnHF/RR regression lines between free and paced breathing. The lnHF/RR relationship is weaker when derived from between-subject recordings than from repeated within-subject samples. lnHF/RR showed evidence of saturation at ∼45 bpm with free breathing. With paced breathing, a deflection in lnHF was found outside the recorded RR interval range (∼41 bpm). Paced breathing creates a stronger lnHF/RR relationship. The slope of the lnHF/RR regression line with paced breathing is significantly different from that observed with free breathing. It appears that lnHF is a valid index of vagal outflow, except in subjects with very low heart rates. Paced breathing data collection protocols

  2. Global longitudinal strain corrected by RR interval is a superior predictor of all-cause mortality in patients with systolic heart failure and atrial fibrillation

    DEFF Research Database (Denmark)

    Modin, Daniel; Sengeløv, Morten; Jørgensen, Peter Godsk


    AIMS: Quantification of systolic function in patients with atrial fibrillation (AF) is challenging. A novel approach, based on RR interval correction, to counteract the varying heart cycle lengths in AF has recently been proposed. Whether this method is superior in patients with systolic heart fa...

  3. Global longitudinal strain corrected by RR interval is a superior predictor of all-cause mortality in patients with systolic heart failure and atrial fibrillation

    DEFF Research Database (Denmark)

    Modin, Daniel; Sengeløv, Morten; Jørgensen, Peter Godsk


    failure (HFrEF) with AF remains unknown. This study investigates the prognostic value of RR interval-corrected peak global longitudinal strain {GLSc = GLS/[RR^(1/2)]} in relation to all-cause mortality in HFrEF patients displaying AF during echocardiographic examination. METHODS AND RESULTS......: Echocardiograms from 151 patients with HFrEF and AF during examination were analysed offline. Peak global longitudinal strain (GLS) was averaged from 18 myocardial segments obtained from three apical views. GLS was indexed with the square root of the RR interval {GLSc = GLS/[RR^(1/2)]}. Endpoint was all......-cause mortality. During a median follow-up of 2.7 years, 40 patients (26.5%) died. Neither uncorrected GLS (P = 0.056) nor left ventricular ejection fraction (P = 0.053) was significantly associated with all-cause mortality. After RR^(1/2) indexation, GLSc became a significant predictor of all-cause mortality...

  4. [Evaluation of the principles of distribution of electrocardiographic R-R intervals for elaboration of methods of automated diagnosis of cardiac rhythm disorders]. (United States)

    Tsukerman, B M; Finkel'shteĭn, I E


    A statistical analysis of prolonged ECG records has been carried out in patients with various heart rhythm and conductivity disorders. The distribution of absolute R-R duration values and relationships between adjacent intervals have been examined. A two-step algorithm has been constructed that excludes anomalous and "suspicious" intervals from a sample of consecutively recorded R-R intervals, until only the intervals between contractions of veritably sinus origin remain in the sample. The algorithm has been developed into a programme for microcomputer Electronica NC-80. It operates reliably even in cases of complex combined rhythm and conductivity disorders.

  5. A novel pathophysiologic phenomenon in cachexic patients with chronic obstructive pulmonary disease: the relationship between the circadian rhythm of circulating leptin and the very low-frequency component of heart rate variability. (United States)

    Takabatake, N; Nakamura, H; Minamihaba, O; Inage, M; Inoue, S; Kagaya, S; Yamaki, M; Tomoike, H


    Cachexic patients with chronic obstructive pulmonary disease (COPD) show abnormalities of the autonomic nervous system (ANS), neuroendocrine function, and energy expenditure. Leptin has been implicated in the regulation of ANS, neuroendocine function, and thermogenesis in humans. We assessed the physiologic significance of the circadian rhythm of circulating leptin using power spectrum analysis of heart rate variability (HRV) in nine cachexic male patients with COPD, eight noncachexic patients with COPD, and seven healthy control subjects. A diurnal pattern of 24-h leptin levels was present in both the control subjects (analysis of variance [ANOVA]; F = 7.80, p COPD patients (F = 9.29, p COPD patients (F = 2.09, p = NS). Analysis of HRV demonstrated that the diurnal rhythm of 24-h very low frequency (VLF; 0.003 to 0.04 Hz) showed significantly identical fluctuations with those of 24-h leptin levels, in all of the three groups (r = 0.388, p leptin has clinical importance in the pathophysiologic features in cachexic patients with COPD.

  6. Power law behavior of RR-interval variability in healthy middle-aged persons, patients with recent acute myocardial infarction, and patients with heart transplants (United States)

    Bigger, J. T. Jr; Steinman, R. C.; Rolnitzky, L. M.; Fleiss, J. L.; Albrecht, P.; Cohen, R. J.


    BACKGROUND. The purposes of the present study were (1) to establish normal values for the regression of log(power) on log(frequency) for, RR-interval fluctuations in healthy middle-aged persons, (2) to determine the effects of myocardial infarction on the regression of log(power) on log(frequency), (3) to determine the effect of cardiac denervation on the regression of log(power) on log(frequency), and (4) to assess the ability of power law regression parameters to predict death after myocardial infarction. METHODS AND RESULTS. We studied three groups: (1) 715 patients with recent myocardial infarction; (2) 274 healthy persons age and sex matched to the infarct sample; and (3) 19 patients with heart transplants. Twenty-four-hour RR-interval power spectra were computed using fast Fourier transforms and log(power) was regressed on log(frequency) between 10(-4) and 10(-2) Hz. There was a power law relation between log(power) and log(frequency). That is, the function described a descending straight line that had a slope of approximately -1 in healthy subjects. For the myocardial infarction group, the regression line for log(power) on log(frequency) was shifted downward and had a steeper negative slope (-1.15). The transplant (denervated) group showed a larger downward shift in the regression line and a much steeper negative slope (-2.08). The correlation between traditional power spectral bands and slope was weak, and that with log(power) at 10(-4) Hz was only moderate. Slope and log(power) at 10(-4) Hz were used to predict mortality and were compared with the predictive value of traditional power spectral bands. Slope and log(power) at 10(-4) Hz were excellent predictors of all-cause mortality or arrhythmic death. To optimize the prediction of death, we calculated a log(power) intercept that was uncorrelated with the slope of the power law regression line. We found that the combination of slope and zero-correlation log(power) was an outstanding predictor, with a

  7. Autonomic nervous system under ketamine/ xylazine and pentobarbital anaesthesia in a Wistar rat model: a chronobiological view. (United States)

    Svorc, P; Bačová, I; Svorc, P; Bužga, M


    The aim of the present study was to determine the effect of ketamine/ xylazine and pentobarbital anaesthesia on heart rate variability as a marker of autonomic nervous system activity. The experiments were performed in ketamine/ xylazine (10 mg/kg/15 mg/kg) and pentobarbital (40 mg/kg, i.p.) anaesthetized female Wistar rats, after adaptation to a light-dark cycle of 12 hours light: 12 hours dark. Heart rate variability parameters (RR interval, power VLF (very low frequency), power LF (low frequency), power HF (high frequency) and relative powers) were evaluated during spontaneous breathing as a function of the light-dark cycle (LD cycle). Significant LD differences were found in the duration of RR intervals in ketamine/xylazine compared with pentobarbital-anaesthetized rats. Correlation analysis revealed moderate dependency between the RR interval duration and HF and LF power parameters in ketamine/xylazine anaesthesia in both light and dark parts of the cycle. In pentobarbital-anaesthetized rats, correlation analysis demonstrated a moderate dependence between RR interval duration and HF and VLF power parameters, but only in the dark part of the LD cycle. Ketamine/xylazine anaesthesia increased parasympathetic activity, and suppressed sympathetic and baroreceptor activity independently of the light-dark cycle. LD differences in RR interval duration were not eliminated. Pentobarbital anaesthesia increased parasympathetic activity, decreased sympathetic and baroreceptor activity, and eliminated LD differences in RR interval duration.

  8. Autonomic Nervous System under Ketamine/xylazine and Pentobarbital Anaesthesia in a Wistar Rat Model: A Chronobiological View

    Directory of Open Access Journals (Sweden)

    Pavol Švorc, Jr.


    Full Text Available The aim of the present study was to determine the effect of ketamine/xylazine and pentobarbital anaesthesia on heart rate variability as a marker of autonomic nervous system activity. The experiments were performed in ketamine/xylazine (10 mg/kg/15 mg/kg and pentobarbital (40 mg/kg, i.p. anaesthetized female Wistar rats, after adaptation to a light-dark cycle of 12 hours light: 12 hours dark. Heart rate variability parameters (RR interval, power  VLF (very low frequency, power LF (low frequency, power HF (high frequency and relative powers were evaluated during spontaneous breathing as a function of the light-dark cycle (LD cycle. Significant LD differences were found in the duration of RR intervals in ketamine/xylazine compared with pentobarbital-anaesthetized rats. Correlation analysis revealed moderate dependency between the RR interval duration and HF and LF power parameters in ketamine/xylazine anaesthesia in both light and dark parts of the cycle. In pentobarbital-anaesthetized rats, correlation analysis demonstrated a moderate dependence between RR interval duration and HF and  VLF power parameters, but only in the dark part of the LD cycle. Ketamine/xylazine anaesthesia increased parasympathetic activity, and suppressed sympathetic and baroreceptor activity independently of the light-dark cycle. LD differences in RR interval duration were not eliminated. Pentobarbital anaesthesia increased parasympathetic activity, decreased sympathetic and baroreceptor activity, and eliminated LD differences in RR interval duration.

  9. Observation of very low frequency emissions at Indian Antarctic ...

    Indian Academy of Sciences (India)

    to most of these theories is the assumption that the energy of emissions is derived from the kinetic energy of electrons populating the magnetosphere or the .... [25]. However, in this mechanism the appearance of a succession of discrete elements remains unresolved. 776. Pramana – J. Phys., Vol. 61, No. 4, October 2003 ...

  10. Observation of very low frequency emissions at Indian Antarctic ...

    Indian Academy of Sciences (India)

    of propagation from source to the observation point, (b) existence of the source of en- ergy, and (c) coupling mechanism which ... instrument has been ruled out. The hiss emission continued for more ... However, in this mechanism the appearance of a succession of discrete elements remains unresolved. 776. Pramana – J.

  11. Observation of very low frequency emissions at Indian Antarctic ...

    Indian Academy of Sciences (India)

    Recently, we have succeeded in recording VLF emissions at the Indian Antarctic station, Maitri (geom. lat. 62° S, geom. long. 57.23°E, =4.5) using a T-type antenna, pre/main amplifiers and digital audio tape recorder. VLF hiss in the frequency ranges 11–13 kHz and 13–14.5 kHz and some riser-type emissions in the ...

  12. A generation mechanism for discrete very low frequency emissions ...

    Indian Academy of Sciences (India)

    for various temporal and spectral features of discrete VLF emissions recorded at Varanasi is presented on the ... parameters: fmin = 2.4 kHz, fmax = 6 kHz, average fUB = 5.5 kHz, average frequency sweep rate, df/dt = 2 kHz/s and average duration of each discrete element, T = 0.5 s. 1110. Pramana – J. Phys., Vol. 65, No.

  13. VLF/LF (Very Low Frequency/Low Frequency) Reflection Properties of the Low Latitude Ionosphere (United States)


    pleasure for the U.S. personnel. Although it is virtually impossible to mention all the individuals who contributed, we wish to especially ... Educacional da Regiao de Blumenau (FURB), who planned the day-to-day experimental efforts and who provided valuable technical Insight and guidance to all...or more grazing incidence angle, with the trend being especially pronounced in the daytime. Figure 23 shows 20 kHz reflectiont coefficients derived

  14. Novel Euler-LaCoste linkage as a very low frequency vertical vibration isolator. (United States)

    Hosain, M A; Sirr, A; Ju, L; Blair, D G


    LaCoste linkage vibration isolators have shown excellent performance for ultra-low frequency vertical vibration isolation. However, such isolators depend on the use of conventional pre-stressed coil springs, which suffer from creep. Here, we show that compressional Euler springs can be configured to create a stable tension unit for use in a LaCoste structure. In a proof of concept experiment, we demonstrate a vertical resonance frequency of 0.15 Hz in an Euler-LaCoste configuration with 200 mm height. The system enables the use of very low creep maraging steel as spring elements to eliminate the creep while minimising spring mass and reducing the effect of parasitic resonances. Larger scale systems with optimized Euler spring boundary conditions should achieve performance suitable for applications on third generation gravitational wave detectors such as the proposed Einstein telescope.

  15. Shared Genetic Influences on ADHD Symptoms and Very Low-Frequency EEG Activity: A Twin Study (United States)

    Tye, Charlotte; Rijsdijk, Fruhling; Greven, Corina U.; Kuntsi, Jonna; Asherson, Philip; McLoughlin, Grainne


    Background: Attention deficit hyperactivity disorder (ADHD) is a common and highly heritable neurodevelopmental disorder with a complex aetiology. The identification of candidate intermediate phenotypes that are both heritable and genetically linked to ADHD may facilitate the detection of susceptibility genes and elucidate aetiological pathways.…


    stations NPM and Haiku in Hawaii and NPG near Seattle, Washington. These data were recorded aboard an aircraft while in flight between California, Guam...26.1 kc/s. The Haiku transmissions were on 16.6 and 19.8 kc/s, while NPG was on 18.6 kc/s continuously. The experimental field-strength-versus

  17. Dispersion by pulsars, magnetars, fast radio bursts and massive electromagnetism at very low frequencies

    NARCIS (Netherlands)

    Bentum, Marinus Jan; Bonetti, Luca; Spallicci, Alessandro D.A.M.


    Our understanding of the universe relies mostly on electromagnetism. As photons are the messengers, fundamental physics is concerned in testing their properties. Photon mass upper limits have been earlier set through pulsar observations, but new investigations are offered by the excess of dispersion

  18. Unexpected very low frequency (VLF) radio events recorded by the ionospheric satellite DEMETER

    Czech Academy of Sciences Publication Activity Database

    Parrot, M.; Berthelier, J. J.; Blecki, J.; Brochot, J. Y.; Hobara, Y.; Lagoutte, D.; Lebreton, J. P.; Němec, F.; Onishi, T.; Pincon, J. L.; Píša, David; Santolík, Ondřej; Sauvaud, J. A.; Slominska, E.


    Roč. 36, č. 3 (2015), s. 483-511 ISSN 0169-3298 R&D Projects: GA ČR(CZ) GA14-31899S; GA MŠk LH12231 Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M100421206; Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M100421206 Institutional support: RVO:68378289 Keywords : ionosphere * natural and man-made VLF radio emissions * anomalies Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.622, year: 2015

  19. Powering autonomous sensors with miniaturized piezoelectric based energy harvesting devices operating at very low frequency

    International Nuclear Information System (INIS)

    Ferin, G; Bantignies, C; Khanh, H Le; Flesch, E; Nguyen-Dinh, A


    Harvesting energy from ambient mechanical vibrations is a smart and efficient way to power autonomous sensors and support innovative developments in IoT (Internet of Things), WSN (Wireless Sensor Network) and even implantable medical devices. Beyond the environmental operating conditions, efficiency of such devices is mainly related to energy source properties like the amplitude of vibrations and its spectral contain and some of these applications exhibit a quite low frequency spectrum where harvesting surrounding mechanical energy make sense, typically 5-50Hz for implantable medical devices or 50Hz-150Hz for industrial machines. Harvesting such low frequency vibrations is a challenge since it leads to adapt the resonator geometries to the targeted frequency or to use out-off band indirect harvesting strategies. In this paper we present a piezoelectric based vibrational energy harvesting device (PEH) which could be integrated into a biocompatible package to power implantable sensor or therapeutic medical devices. The presented architecture is a serial bimorph laminated with ultra-thinned (ranging from 15μm to 100μm) outer PZT “skins” that could operate at a “very low frequency”, below 25Hz typically. The core process flow is disclosed and performances highlighted with regards to other low frequency demonstrations. (paper)

  20. Measurement of Complex Sensitivity of Data Channels in Hydrophone Line Array at Very Low Frequency (United States)


    hydrophones and their associated signal conditioning circuits. BRIEF DESCRIPTION OF THE DRAWINGS [0026] Other objects, features and advantages of...associated signal conditioning circuits. Since the measurement SNR may be as low as six to ten decibels; the complex sensitivity as computed above and as...described above. The process, illustrated in FIG. 2 and FIG. 3 is summarized as the operand to the summation operator in Equation Attorney Docket

  1. Line radiation events induced by very low frequency transmitters observed by the DEMETER spacecraft

    Czech Academy of Sciences Publication Activity Database

    Němec, F.; Čížek, K.; Parrot, M.; Santolík, Ondřej; Záhlava, J.


    Roč. 122, č. 7 (2017), s. 7226-7239 ISSN 2169-9380 R&D Projects: GA ČR(CZ) GA17-07027S; GA MŠk(CZ) LH15304 Grant - others:AV ČR(CZ) AP1401 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:68378289 Keywords : low-altitude satellite * harmonic radiation * impenetrable barrier * bicoherence analysis Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 2.733, year: 2016

  2. Powering autonomous sensors with miniaturized piezoelectric based energy harvesting devices operating at very low frequency (United States)

    Ferin, G.; Bantignies, C.; Le Khanh, H.; Flesch, E.; Nguyen-Dinh, A.


    Harvesting energy from ambient mechanical vibrations is a smart and efficient way to power autonomous sensors and support innovative developments in IoT (Internet of Things), WSN (Wireless Sensor Network) and even implantable medical devices. Beyond the environmental operating conditions, efficiency of such devices is mainly related to energy source properties like the amplitude of vibrations and its spectral contain and some of these applications exhibit a quite low frequency spectrum where harvesting surrounding mechanical energy make sense, typically 5-50Hz for implantable medical devices or 50Hz-150Hz for industrial machines. Harvesting such low frequency vibrations is a challenge since it leads to adapt the resonator geometries to the targeted frequency or to use out-off band indirect harvesting strategies. In this paper we present a piezoelectric based vibrational energy harvesting device (PEH) which could be integrated into a biocompatible package to power implantable sensor or therapeutic medical devices. The presented architecture is a serial bimorph laminated with ultra-thinned (ranging from 15μm to 100μm) outer PZT “skins” that could operate at a “very low frequency”, below 25Hz typically. The core process flow is disclosed and performances highlighted with regards to other low frequency demonstrations.

  3. Very low frequency valuation of a modulated beam of electrons: an application to the ARAKS experiment

    International Nuclear Information System (INIS)

    Ahmadi, L.


    The purpose of the ARAKS experiments was to study the effects due to the injection of energy electrons into the aurora zone. Here we analyse the TBF (2, 4 and 6 kHz) signals observed on the basis of interpretations in a closed or radiated field. We show that these signals are of an electromagnetic nature below fsub(HB) = 5 kHz and electrostatic above that figure, that they are correlated with the functioning of the electron cannon and independent of the electrons' angle of attack. They propagate in the electronic hissing mode. At frequencies below fsub(HB), the main contribution comes from the close field, whereas it comes from the radiated field for f greater than fsub(HB) [fr

  4. Very-low-frequency and low-frequency electric and magnetic fields associated with electric shuttle bus wireless charging. (United States)

    Tell, R A; Kavet, Robert; Bailey, J R; Halliwell, John


    Tests conducted to date at the University of Tennessee at Chattanooga (UTC) indicate that wireless charging of the Chattanooga Area Regional Transportation Authority's (CARTA) downtown shuttle bus, currently operating with off-board battery charging technology, offers significant improvements in performance and cost. The system operates at a frequency of 20 kHz and a peak power of 60 kW. Because the system's wireless charging is expected to occur during a nominal 3-min charging period with passengers on-board, the magnetic and electric fields associated with charging were characterised at UTC's Advanced Vehicle Test Facility and compared with established human exposure limits. The two most prominent exposure limits are those published by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and the Institute for Electrical and Electronic Engineers (IEEE). Both organisations include limits for groups who are trained (workers in specific industries) to be aware of electromagnetic environments and their potential hazards, as well as a lower set of limits for the general public, who are assumed to lack such awareness. None of the magnetic or electric fields measured either within or outside the bus during charging exceeded either the ICNIRP or the IEEE exposure limits for the general public.

  5. TE/TM (Transverse Magnetic/Transverse Electric) Height Profile Measurements of Transpolar VLF (Very Low Frequency) Signals, (United States)


    GQD U.K. 096 3740 [NA]’ 19.6 GBZ Criggion, U.K. 096 3740 10, 20.25 IDO Rome, Italy 086 5260 [NA] 21.4 NSS Annapolis, Md. 190 4180 266 23.4 NPM Haiku ...night no yes yes 23.4 Haiku , Hawaii night no yes yes 24.8 Jim Creek, Wash. night no yes yes 26.1 TACAMO night no no yes 50 TE 40 TM -- 30- M 20- 10

  6. Research Plans for Improving Understanding of Effects of Very Low-Frequency Noise of Heavy Lift Rotorcraft (United States)

    Fidell, Sanford; Horonieff, Richard D.; Schmitz, Fredric H.


    This report reviews the English-language technical literature on infrasonic and low-frequency noise effects; identifies the most salient effects of noise produced by a future large civil tiltrotor aircraft on crew, passengers, and communities near landing areas; and recommends research needed to improve understanding of the effects of such noise on passengers, crew, and residents of areas near landing pads.

  7. Detection of Very Low-Frequency Quasi-Periodic Oscillations in the 2015 Outburst of V404 Cygni

    DEFF Research Database (Denmark)

    Huppenkothen, D.; Younes, G.; Ingram, A.


    In June 2015, the black hole X-ray binary (BHXRB) V404 Cygni went into outburst for the first time since 1989. Here, we present a comprehensive search for quasi-periodic oscillations (QPOs) of V404 Cygni during its recent outburst, utilizing data from six instruments on board five different X...

  8. Acoustic Propagation Loss Predictions for a Site on the Bermuda Rise at Low and Very Low Frequencies (United States)


    Specialized Conference, edited by A. Lara, C. Ranz and C. Carbo (Consejo Superior de Investigaciones Cientificas , Madrid, 1987). 2. R. E. Christensen, J. A...Conference, edited by A. Lara, C. Ranz and C. Carbo (Con- sejo Superior de Investigaciones Cientificas , Madrid, 1987). 16. E. L. Hamilton, "Geo-acoustic


    Energy Technology Data Exchange (ETDEWEB)

    Huppenkothen, D. [Center for Data Science, New York University, 726 Broadway, 7th Floor, New York, NY 10003 (United States); Younes, G.; Kouveliotou, C. [Department of Physics, The George Washington University, Washington, DC 20052 (United States); Ingram, A.; Van der Klis, M. [Anton Pannekoek Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands); Göğüş, E. [Sabancı University, Orhanlı-Tuzla, İstanbul 34956 (Turkey); Bachetti, M. [INAF/Osservatorio Astronomico di Cagliari, via della Scienza 5, I-09047 Selargius (Italy); Sánchez-Fernández, C.; Kuulkers, E. [European Space Astronomy Centre (ESA/ESAC), Science Operations Department, E-28691 Villanueva de la Cañada, Madrid (Spain); Chenevez, J. [DTU Space—National Space Institute, Technical University of Denmark, Elektrovej 327-328, DK-2800 Lyngby (Denmark); Motta, S. [University of Oxford, Department of Physics, Astrophysics, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Granot, J. [Department of Natural Sciences, The Open University of Israel, 1 University Road, P.O. Box 808, Raanana 43537 (Israel); Gehrels, N. [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Tomsick, J. A. [Space Sciences Laboratory, 7 Gauss Way, University of California, Berkeley, CA 94720-7450 (United States); Walton, D. J., E-mail: [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States)


    In 2015 June, the black hole X-ray binary (BHXRB) V404 Cygni went into outburst for the first time since 1989. Here, we present a comprehensive search for quasi-periodic oscillations (QPOs) of V404 Cygni during its recent outburst, utilizing data from six instruments on board five different X-ray missions: Swift /XRT, Fermi /GBM, Chandra /ACIS, INTEGRAL ’s IBIS/ISGRI and JEM-X, and NuSTAR . We report the detection of a QPO at 18 mHz simultaneously with both Fermi /GBM and Swift /XRT, another example of a rare but slowly growing new class of mHz-QPOs in BHXRBs linked to sources with a high orbital inclination. Additionally, we find a duo of QPOs in a Chandra /ACIS observation at 73 mHz and 1.03 Hz, as well as a QPO at 136 mHz in a single Swift /XRT observation that can be interpreted as standard Type-C QPOs. Aside from the detected QPOs, there is significant structure in the broadband power, with a strong feature observable in the Chandra observations between 0.1 and 1 Hz. We discuss our results in the context of current models for QPO formation.

  10. Very-low-frequency and low-frequency electric and magnetic fields associated with electric shuttle bus wireless charging

    International Nuclear Information System (INIS)

    Tell, R. A.; Kavet, R.; Bailey, J. R.; Halliwell, J.


    Tests conducted to date at the University of Tennessee at Chattanooga (UTC) indicate that wireless charging of the Chattanooga Area Regional Transportation Authority's (CARTA) downtown shuttle bus, currently operating with off-board battery charging technology, offers significant improvements in performance and cost. The system operates at a frequency of 20 kHz and a peak power of 60 kW. Because the system's wireless charging is expected to occur during a nominal 3-min charging period with passengers on-board, the magnetic and electric fields associated with charging were characterised at UTC's Advanced Vehicle Test Facility and compared with established human exposure limits. The two most prominent exposure limits are those published by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and the Institute for Electrical and Electronic Engineers (IEEE). Both organisations include limits for groups who are trained (workers in specific industries) to be aware of electromagnetic environments and their potential hazards, as well as a lower set of limits for the general public, who are assumed to lack such awareness. None of the magnetic or electric fields measured either within or outside the bus during charging exceeded either the ICNIRP or the IEEE exposure limits for the general public. (authors)

  11. Very low frequency radio events with a reduced intensity observed by the low-altitude DEMETER spacecraft

    Czech Academy of Sciences Publication Activity Database

    Záhlava, J.; Němec, F.; Santolík, Ondřej; Kolmašová, Ivana; Parrot, M.; Rodger, C. J.


    Roč. 120, č. 11 (2015), s. 9781-9794 ISSN 2169-9380 R&D Projects: GA ČR(CZ) GA14-31899S Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M100421206 Institutional support: RVO:68378289 Keywords : magnetosphere * DEMETER * VLF radio events Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.318, year: 2015

  12. In Vivo pO2 Imaging of Tumors: Oxymetry with Very Low-Frequency Electron Paramagnetic Resonance. (United States)

    Epel, Boris; Halpern, Howard J


    For over a century, it has been known that tumor hypoxia, regions of a tumor with low levels of oxygenation, are important contributors to tumor resistance to radiation therapy and failure of radiation treatment of cancer. Recently, using novel pulse electron paramagnetic resonance (EPR) oxygen imaging, near absolute images of the partial pressure of oxygen (pO2) in tumors of living animals have been obtained. We discuss here the means by which EPR signals can be obtained in living tissues and tumors. We review development of EPR methods to image the pO2 in tumors and the potential for the pO2 image acquisition in human subjects. © 2015 Elsevier Inc. All rights reserved.

  13. In vivo pO2 imaging of tumors: Oxymetry with very low frequency Electron Paramagnetic Resonance (United States)

    Epel, Boris; Halpern, Howard J.


    For over a century it has been known that tumor hypoxia, regions of a tumor with low levels of oxygenation, are important contributors to tumor resistance to radiation therapy and failure of radiation treatment of cancer. Recently, using novel pulse electron paramagnetic resonance (EPR) oxygen imaging, near absolute images of the partial pressure of oxygen (pO2) in tumors of living animals have been obtained. We discuss here the means by which EPR signals can be obtained in living tissues and tumors. We review development of EPR methods to image the pO2 in tumors and the potential for the pO2 image acquisition in human subjects. PMID:26477263

  14. Clustering of RR intervals predicts effective electrical cardioversion for atrial fibrillation

    NARCIS (Netherlands)

    Van den Berg, MP; Van Noord, T; Brouwer, J; Haaksma, J; Van Veldhuisen, DJ; Crijns, HJGM; Van Gelder, IC

    Electrical Cardioversion for Atrial Fibrillation. Introduction: Atrial fibrillation (AF) is characterized by an irregularly irregular ("random") heart beat. However, controversy exists whether the ventricular rhythm in AF is truly random. We investigated randomness by constructing three-dimensional

  15. Automatic Detection of Atrial Fibrillation Using Basic Shannon Entropy of RR Interval Feature (United States)

    Afdala, Adfal; Nuryani, Nuryani; Satriyo Nugroho, Anto


    Atrial Fibrillation is one of heart disease, that common characterized by irregularity heart beat. Atrial fibrillation leads to severe complications such as cardiac failure with the subsequent risk of a stroke. A method to detect atrial fibrillation is needed to prevent a risk of atrial fibrillation. This research uses data from physionet in atrial fibrillation database category. The performance of Shannon entropy has the highest accuracy if a threshold is 0.5 with accuracy 89.79%, sensitivity 91.04% and specificity 89.01%. Based on the result we get a conclusion, the ability of Shannon entropy to detect atrial fibrillation is good.

  16. Evaluation of very low frequencies of ATWS and PLOHS in a loop-type FBR plant by making use of inherently safe features

    International Nuclear Information System (INIS)

    Sakata, K.; Koyama, K.; Aoi, S.; Simonelli, R.B.; Wallace, I.T.


    Frequencies of ATWS (Anticipated Transient Without Scram) and PLOHS (Protected Loss of Heat Sink) for a large loop-type FBR plant were evaluated by applying PSA methodologies. The frequencies were found to be so low that ATWS and PLOHS could be excluded from candidates of the design basis events. Furthermore, the inherently safe features introduced to the system design were verified to be very effective for reduction of the Probability of CCF (Common Cause Failure), which deteriorates reliability of both the reactor shutdown and the decay heat removal systems. (orig.)

  17. Detection of Atrial Fibrillation Using Artifical Neural Network with Power Spectrum Density of RR Interval of Electrocardiogram (United States)

    Afdala, Adfal; Nuryani, Nuryani; Satrio Nugroho, Anto


    Atrial fibrillation (AF) is a disorder of the heart with fairly high mortality in adults. AF is a common heart arrythmia which is characterized by a missing or irregular contraction of atria. Therefore, finding a method to detect atrial fibrillation is necessary. In this article a system to detect atrial fibrillation has been proposed. Detection system utilized backpropagation artifical neural network. Data input in this method includes power spectrum density of R-peaks interval of electrocardiogram which is selected by wrapping method. This research uses parameter learning rate, momentum, epoch and hidden layer. System produces good performance with accuracy, sensitivity, and specificity of 83.55%, 86.72 % and 81.47 %, respectively.

  18. Heart rate variability under resting conditions in postmenopausal and young women

    Directory of Open Access Journals (Sweden)

    Ribeiro T.F.


    Full Text Available The aim of the present study was to compare the modulation of heart rate in a group of postmenopausal women to that of a group of young women under resting conditions on the basis of R-R interval variability. Ten healthy postmenopausal women (mean ± SD, 58.3 ± 6.8 years and 10 healthy young women (mean ± SD, 21.6 ± 0.82 years were submitted to a control resting electrocardiogram (ECG in the supine and sitting positions over a period of 6 min. The ECG was obtained from a one-channel heart monitor at the CM5 lead and processed and stored using an analog to digital converter connected to a microcomputer. R-R intervals were calculated on a beat-to-beat basis from the ECG recording in real time using a signal-processing software. Heart rate variability (HRV was expressed as standard deviation (RMSM and mean square root (RMSSD. In the supine position, the postmenopausal group showed significantly lower (P<0.05 median values of RMSM (34.9 and RMSSD (22.32 than the young group (RMSM: 62.11 and RMSSD: 49.1. The same occurred in the sitting position (RMSM: 33.0 and RMSSD: 18.9 compared to RMSM: 57.6 and RMSSD: 42.8 for the young group. These results indicate a decrease in parasympathetic modulation in postmenopausal women compared to young women which was possibly due both to the influence of age and hormonal factors. Thus, time domain HRV proved to be a noninvasive and sensitive method for the identification of changes in autonomic modulation of the sinus node in postmenopausal women.

  19. The regulatory framework of the radio frequency spectrum under ...

    African Journals Online (AJOL)

    The Radio Frequency Spectrum (R.F.S) is the entire range of wavelengths of electromagnetic radiation in the frequency range of 3 kilohertz (KHZ) to 40,000 megahertz (MHZ). The RFS is arbitrarily divided into a number of wavebands, from very low frequencies (long wavelengths) to ultra-high and microwave frequencies ...

  20. Under Under Under / Merit Kask

    Index Scriptorium Estoniae

    Kask, Merit


    20. nov. esietendub Kumu auditooriumis MTÜ Ühenduse R.A.A.A.M teatriprojekt "Under" poetess Marie Underist. Lavastajad Merle Karusoo ja Raimo Pass, kunstnik Jaagup Roomet, helilooja Urmas Lattikas, peaosas Katrin Saukas

  1. Very low frequencies of Toll-like receptor 2 supposed-2029T and 2258A (RS5743708) mutant alleles in southern Brazilian critically ill patients: would it be a lack of worldwide-accepted clinical applications of Toll-like receptor 2 variants? (United States)

    Thurow, Helena Strelow; Sarturi, Cladinara Roberts; Fallavena, Paulo Roberto Vargas; Paludo, Francis Jackson de Oliveira; Picanço, Juliane Bentes; Fraga, Lucas Rosa; Graebin, Pietra; de Souza, Vinícius Carolino; Dias, Fernando Suparregui; Nóbrega, Otávio de Tolêdo; Alho, Clarice Sampaio


    Toll-like receptor 2 (TLR2) is a recognition receptor for the widest repertoire of pathogen-associated molecular patterns. Two polymorphisms of TLR2 could be linked to reduced nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) activation and to increased risk of infection (supposed-2029C>T and 2258G>A). We investigated the supposed-2029C>T and 2258G>A TLR2 polymorphisms in 422 critically ill patients of European origin from southern Brazil (295 with sepsis and 127 without sepsis) and reviewed 33 studies on these polymorphisms, conducting a quality assessment with a score system. Among our patients we found only one heterozygote (1/422) for the supposed-2029C>T and none for the 2258G>A (0/422) single nucleotide polymorphism (SNP). We were unable to find a clinical application of supposed-2029T and 2258A allele analyses in our southern Brazilian population. Our review detected that current TLR2 SNP assays had very controversial and contradictory results derived from reports with a variety of investigation quality criteria. We suggest that, if analyzed alone, the supposed-2029C>T and 2258G>A TLR2 SNP are not good candidates for genetic markers in studies that search for direct or indirect clinical applications between genotype and phenotype. Future efforts to improve the knowledge and to provide other simultaneous genetic markers might reveal a more effective TLR2 effect on the susceptibility to infectious diseases.

  2. The Impact of Respiratory Events on the Autonomic Nervous System during Sleep. (United States)

    Liang, Jiuxing; Zhang, Xiangmin; Luo, Yuxi; Wang, Tingting; Sun, Lin; Huang, Shaoxiong


    Sleep apnea hypopnea syndrome (SAHS) is an independent risk factor for cardiovascular diseases. However, the pathophysiology between them is not yet clear. This paper seeks to understand how respiratory events impact the cardiovascular system by heart rate variability. We compared the differences between successional pathological respiratory events (PR) and pure normal respiration (NR) during sleep. The transitions between normal and pathological respiration (TR) were also analyzed. Thirteen patients who suffered moderate or severe SAHS were enrolled in this study. The results demonstrate that the beat-to-beat interval (RR interval) mean value and sample entropy are significantly lower during PR than during NR. RR interval standard deviation, the power of very low frequency (VLF) and low frequency (LF), total power, and the low frequency/high frequency (LF/HF) ratio were significantly larger during PR than during NR. However, the high frequency (HF) power was not significantly different between normal and pathological respiration. Additionally, the trends during TR also supported these significant differences. The results indicate that during pathological respiration, as the heart rate and its volatility increase, the complexity of its rhythm decreases. We conclude that the energy of the autonomic nervous system rapidly increases during pathological respiration, especially at the beginning. The HF power does not significantly change to modulate the heart rhythm, but the activity of the sympathetic nervous system will significantly increase, resulting in the imbalance of the LF/HF ratio. In addition to these findings, this paper discusses the influence of arousal on these indices during TR.

  3. The differences between patients with panic disorder and healthy controls in psychophysiological stress profile. (United States)

    Kotianova, Antonia; Kotian, Michal; Slepecky, Milos; Chupacova, Michaela; Prasko, Jan; Tonhajzerova, Ingrid


    Alarming somatic symptoms, in particular, cardiovascular symptoms, are the characteristic feature of panic attacks. Increased cardiac mortality and morbidity have been found in these patients. Power spectral analysis of electrocardiogram R-R intervals is known to be a particularly successful tool in the detection of autonomic instabilities in various clinical disorders. Our study aimed to compare patients with panic disorder and healthy controls in heart rate variation (HRV) parameters (very-low-frequency [VLF], low-frequency [LF], and high-frequency [HF] band components of R-R interval) in baseline and during the response to the mental task. We assessed psychophysiological variables in 33 patients with panic disorder (10 men, 23 women; mean age 35.9±10.7 years) and 33 age- and gender-matched healthy controls (10 men, 23 women; mean age 35.8±12.1 years). Patients were treatment naïve. Heart rate, blood pressure, muscle tension, and HRV in basal conditions and after the psychological task were assessed. Power spectrum was computed for VLF (0.003-0.04 Hz), LF (0.04-0.15 Hz), and HF (0.15-0.40 Hz) bands using fast Fourier transformation. In the baseline period, the VLF band was significantly lower in panic disorder group compared to controls ( p panic disorder patients compared to controls ( p panic disorder were characterized by relative sympathetic dominance (reactivity) in response to mental stress compared with healthy controls.

  4. Heart Rate Variability Analysis in Patients with Allergic Rhinitis

    Directory of Open Access Journals (Sweden)

    Ming-Ying Lan


    Full Text Available Background. Very few studies investigate the role of the autonomic nervous system in allergic rhinitis. In this study, we evaluated the autonomic nervous system in allergic rhinitis patients using heart rate variability (HRV analysis. Methods. Eleven patients with allergic rhinitis and 13 healthy controls, aged between 19 and 40 years old, were enrolled in the study. Diagnosis of allergic rhinitis was based on clinical history, symptoms, and positive Phadiatop test. Electrocardiographic recordings on the sitting and supine positions were obtained for HRV analysis. Results. In the supine position, there were no significant statistical differences in very-low-frequency power (VLF, ≤0.04 Hz, low-frequency power (LF, 0.04–0.15 Hz, high-frequency power (HF, 0.15–0.40 Hz, and the ratio of LF to HF (LF/HF between the patient and control groups. The mean RR intervals significantly increased, while LF% and LF/HF significantly decreased in the patient group in the sitting position. Moreover, mean RR intervals, LF, and LF/HF, which were significantly different between the two positions in the control group, did not show a significant change with the posture change in the patient group. Conclusion. These suggest that patients with allergic rhinitis may have poor sympathetic modulation in the sitting position. Autonomic dysfunction may therefore play a role in the pathophysiology of allergic rhinitis.

  5. Sensitivity, specificity and predictive values of linear and nonlinear indices of heart rate variability in stable angina patients

    Directory of Open Access Journals (Sweden)

    Pivatelli Flávio


    Full Text Available Abstract Background Decreased heart rate variability (HRV is related to higher morbidity and mortality. In this study we evaluated the linear and nonlinear indices of the HRV in stable angina patients submitted to coronary angiography. Methods We studied 77 unselected patients for elective coronary angiography, which were divided into two groups: coronary artery disease (CAD and non-CAD groups. For analysis of HRV indices, HRV was recorded beat by beat with the volunteers in the supine position for 40 minutes. We analyzed the linear indices in the time (SDNN [standard deviation of normal to normal], NN50 [total number of adjacent RR intervals with a difference of duration greater than 50ms] and RMSSD [root-mean square of differences] and frequency domains ultra-low frequency (ULF ≤ 0,003 Hz, very low frequency (VLF 0,003 – 0,04 Hz, low frequency (LF (0.04–0.15 Hz, and high frequency (HF (0.15–0.40 Hz as well as the ratio between LF and HF components (LF/HF. In relation to the nonlinear indices we evaluated SD1, SD2, SD1/SD2, approximate entropy (−ApEn, α1, α2, Lyapunov Exponent, Hurst Exponent, autocorrelation and dimension correlation. The definition of the cutoff point of the variables for predictive tests was obtained by the Receiver Operating Characteristic curve (ROC. The area under the ROC curve was calculated by the extended trapezoidal rule, assuming as relevant areas under the curve ≥ 0.650. Results Coronary arterial disease patients presented reduced values of SDNN, RMSSD, NN50, HF, SD1, SD2 and -ApEn. HF ≤ 66 ms2, RMSSD ≤ 23.9 ms, ApEn ≤−0.296 and NN50 ≤ 16 presented the best discriminatory power for the presence of significant coronary obstruction. Conclusion We suggest the use of Heart Rate Variability Analysis in linear and nonlinear domains, for prognostic purposes in patients with stable angina pectoris, in view of their overall impairment.

  6. The chaos and order in human ECG under the influence of the external perturbations (United States)

    Ragulskaya, Maria; Valeriy, Pipin

    model reconstruction of the individual cardiac beat. It is found that the positions of the stationary points of the typical ECG attractor are in vicinities of Q and T waves. Additionally, we find that the stiffness of the beat is important for the general stability of ECG. The given results agues for the increase the relative disorder of the human cardiac system under external perturbations due to changes in the space weather and climatic factors. Also, the results of monitoring show that cardiac system can be stabilized by "internal" (physical) stress. The given difference in the cardiac sys-tem behavior under the different types of stress is obtained in the earth labaratory conditions. However, it should be considered as important factors influencing on the health of cosmonauts during the space missions, as well.

  7. Assessment of Autonomic Function by Phase Rectification of RRInterval Histogram Analysis in Chagas Disease

    Directory of Open Access Journals (Sweden)

    Olivassé Nasari Junior


    Full Text Available Background: In chronic Chagas disease (ChD, impairment of cardiac autonomic function bears prognostic implications. Phase‑rectification of RR-interval series isolates the sympathetic, acceleration phase (AC and parasympathetic, deceleration phase (DC influences on cardiac autonomic modulation. Objective: This study investigated heart rate variability (HRV as a function of RR-interval to assess autonomic function in healthy and ChD subjects. Methods: Control (n = 20 and ChD (n = 20 groups were studied. All underwent 60-min head-up tilt table test under ECG recording. Histogram of RR-interval series was calculated, with 100 ms class, ranging from 600–1100 ms. In each class, mean RR-intervals (MNN and root-mean-squared difference (RMSNN of consecutive normal RR-intervals that suited a particular class were calculated. Average of all RMSNN values in each class was analyzed as function of MNN, in the whole series (RMSNNT, and in AC (RMSNNAC and DC (RMSNNDC phases. Slopes of linear regression lines were compared between groups using Student t-test. Correlation coefficients were tested before comparisons. RMSNN was log-transformed. (α < 0.05. Results: Correlation coefficient was significant in all regressions (p < 0.05. In the control group, RMSNNT, RMSNNAC, and RMSNNDC significantly increased linearly with MNN (p < 0.05. In ChD, only RMSNNAC showed significant increase as a function of MNN, whereas RMSNNT and RMSNNDC did not. Conclusion: HRV increases in proportion with the RR-interval in healthy subjects. This behavior is lost in ChD, particularly in the DC phase, indicating cardiac vagal incompetence.

  8. Arterial-cardiac baroreflex function: insights from repeated squat-stand maneuvers.

    NARCIS (Netherlands)

    Zhang, R.; Claassen, J.A.H.R.; Shibata, S.; Kilic, S.; Martin-Cook, K.; Diaz-Arrastia, R.; Levine, B.D.


    To assess baroreflex function under closed-loop conditions, a new approach was used to generate large and physiological perturbations in arterial pressure. Blood pressure (BP) and R-R interval were recorded continuously in 20 healthy young (33 +/- 8 yr) and eight elderly subjects (66 +/- 6 yr).

  9. Bags Under Eyes (United States)

    Bags under eyes Overview Bags under eyes — mild swelling or puffiness under the eyes — are common as you age. With aging, the tissues around your ... space below your eyes, adding to the swelling. Bags under eyes are usually a cosmetic concern and ...

  10. Solidarity under Attack

    DEFF Research Database (Denmark)

    Meret, Susi; Goffredo, Sergio


  11. PET's indsats under lup

    DEFF Research Database (Denmark)

    Hansen, Peer Henrik


    En undersøgelseskommission nedsat i 1999. Fem medlemmer skal undersøge PET's efterretningsvirksomhed i forhold til politiske partier, faglige konflikter og politisk ideologiske bevægelser i Danmark under den kolde krig. Kommissionens rapport forventes færdig næste år. Udgivelsesdato: 2. juli 2006...

  12. The space multi-arm interferometer and the search for cosmic background gravitational wave radiation (SMILE). (United States)

    Anderson, A. J.

    It is proposed to study the feasibility of constructing a space multi-arm interferometer applicable for the detection of very low frequency gravitational waves using current elements of design. The elements are outlined with particular emphasis placed on the utilization of small inexpensive ion drive get away special modules currently under development.

  13. Flexicurity under afvikling?

    DEFF Research Database (Denmark)

    Schmidt, Johannes Dragsbæk; Crumlin, Jens Voldby


    Flexicurity-strategien er under angreb fra højrefløjen - mens Socialdemokrater og fagbevægelse er lammet Udgivelsesdato: 10 marts......Flexicurity-strategien er under angreb fra højrefløjen - mens Socialdemokrater og fagbevægelse er lammet Udgivelsesdato: 10 marts...

  14. Creativity under the Gun. (United States)

    Amabile, Teresa M.; Hadley, Constance N.; Kramer, Steven J.


    Although many employers think that people are most creative when under time pressure, research indicates that the opposite is true. Data from 177 employees' diaries showed that creative thinking under extreme time pressure is unlikely when people feel on a treadmill or on autopilot; more likely when they feel they are on an expedition or a…

  15. Undersøgelse

    DEFF Research Database (Denmark)

    Hansen, Ernst Albin


    Cykelryttere får for lidt energidrik - og det koster dyrt på de lange distancer. Opsigtsvækkende resultater fra en ny undersøgelse afslører at væske- og energiindtaget under langvarig cykling har stor betydning for præstationen....

  16. Survival pathways under stress

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Survival pathways under stress. Bacteria survive by changing gene expression. pattern. Three important pathways will be discussed: Stringent response. Quorum sensing. Proteins performing function to control oxidative damage.

  17. Preserved heart rate variability during therapeutic hypothermia correlated to 96 hrs neurological outcomes and survival in a pig model of cardiac arrest. (United States)

    Li, Yongqin; Ristagno, Giuseppe; Guan, Jun; Barbut, Denise; Bisera, Joe; Weil, Max Harry; Tang, Wanchun


    Therapeutic hypothermia initiated with cardiopulmonary resuscitation improves neurologic outcomes and survival after prolonged cardiac arrest. However, the potential mechanism by which hypothermia improves neurologic outcomes remains unclear. In the current study, we investigated the effect of rapid head cooling on 96-hr neurologic outcomes and survival by heart rate variability analysis in a pig model of prolonged cardiac arrest. Prospective randomized controlled animal study. University-affiliated research laboratory. Yorkshire-X domestic pigs (Sus scrofa). A protocol of 10 mins of untreated ventricular fibrillation followed by 5 mins of cardiopulmonary resuscitation in a pig model of cardiac arrest was used in this study. Sixteen male domestic pigs weighing between 39 and 45 kg were randomized into two groups, hypothermia (n = 8) and control (n = 8). For the hypothermia group, intranasal-induced head cooling was initiated with cardiopulmonary resuscitation and persisted for 4 hrs after resuscitation. For the control group, cardiopulmonary resuscitation was started with normothermia. Time and frequency domain heart rate variability was calculated in 5-min sections of electrocardiographic recordings at baseline and 4 hrs after resuscitation. Neurologic outcomes were evaluated every 24 hrs during the 96-hr postresuscitation observation period. No differences in the baseline measurement and resuscitation outcome were observed between the groups. However, the 96-hr cerebral performance categories of the hypothermic group were significantly lower than control (1.0 ± 0.0 vs. 4.0 ± 1.9, p = .003). Four hrs after resuscitation, mean RR interval, heart rate variability triangular index, and normalized very-low-frequency power were restored to baseline in the hypothermia group. Square root of the mean squared differences of successive RR intervals and SD of instantaneous RR intervals were significantly improved in the cooled animals compared with controls. A significant

  18. Equity valuation : Under Armour


    Vicente, António Rafael Mendes


    The present dissertation aims to value Under Armour, an American sportswear company. Since Valuation is not an exact science, during the literature review will be presented several valuation methods. Most of the authors mention DCF Valuation as one of the best but it seems impossible for them to reach a consensus about which one is in fact the best. In order to get Under Armour’s target price, a DCF valuation will be made and accompanied by a Relative Valuation that, when it is properly us...

  19. Danmark under overfladen

    DEFF Research Database (Denmark)

    Hjorth, M.; Danø, R.

    "Danmark under overfladen" er et nyt undervisningstilbud til de danske skoler. På Internettet, kan man downloade grundbogen og fire andre temahæfter, samt se film og løse opgaver. "Danmark under overfladen" henvender sig til alle som er interesseret i havbiologi, men...... som undervisningsmateriale retter bogen sig særligt til de ældste klasser i folkeskolen og til det naturfaglige grundforløb i gymnasiet. Denne bog starter med at introducere den naturvidenskabelige arbejdsmetode i kapitel 1. Det er en tankegang som man må gå ind på,...

  20. Solidification under microgravity

    Indian Academy of Sciences (India)

    The paper outlines the broad areas where studies are being conducted under microgravity conditions worldwide viz., biotechnology, combustion science, materials science and fluid physics. The paper presents in particular a review on the various areas of research being pursued in materials science. These include studies ...

  1. Plants under dual attack

    NARCIS (Netherlands)

    Ponzio, C.A.M.


    Though immobile, plants are members of complex environments, and are under constant threat from a wide range of attackers, which includes organisms such as insect herbivores or plant pathogens. Plants have developed sophisticated defenses against these attackers, and include chemical responses such

  2. Care profession under change

    DEFF Research Database (Denmark)

    Rask Eriksen, Tine; Engel, Lisbeth Vinberg; Vedsegaard, Helle

    Backgound and aims: Sygeplejerskemanglen i Danmark er stor. Udfordringerne består i disse år i at rekruttere og fastholde sygeplejestuderende i studiet. Hensigten med projektet er dels at undersøge hvilke livshistoriske omsorgsforudsætninger, de studerende møder med i uddannelsen og dels at beskr...

  3. Network planning under uncertainties (United States)

    Ho, Kwok Shing; Cheung, Kwok Wai


    One of the main focuses for network planning is on the optimization of network resources required to build a network under certain traffic demand projection. Traditionally, the inputs to this type of network planning problems are treated as deterministic. In reality, the varying traffic requirements and fluctuations in network resources can cause uncertainties in the decision models. The failure to include the uncertainties in the network design process can severely affect the feasibility and economics of the network. Therefore, it is essential to find a solution that can be insensitive to the uncertain conditions during the network planning process. As early as in the 1960's, a network planning problem with varying traffic requirements over time had been studied. Up to now, this kind of network planning problems is still being active researched, especially for the VPN network design. Another kind of network planning problems under uncertainties that has been studied actively in the past decade addresses the fluctuations in network resources. One such hotly pursued research topic is survivable network planning. It considers the design of a network under uncertainties brought by the fluctuations in topology to meet the requirement that the network remains intact up to a certain number of faults occurring anywhere in the network. Recently, the authors proposed a new planning methodology called Generalized Survivable Network that tackles the network design problem under both varying traffic requirements and fluctuations of topology. Although all the above network planning problems handle various kinds of uncertainties, it is hard to find a generic framework under more general uncertainty conditions that allows a more systematic way to solve the problems. With a unified framework, the seemingly diverse models and algorithms can be intimately related and possibly more insights and improvements can be brought out for solving the problem. This motivates us to seek a

  4. Creativity under the gun. (United States)

    Amabile, Teresa M; Hadley, Constance N; Kramer, Steven J


    If you're like most managers, you've worked with people who swear they do their most creative work under tight deadlines. You may use pressure as a management technique, believing it will spur people on to great leaps of insight. You may even manage yourself this way. If so, are you right? Not necessarily, these researchers say. There are instances where ingenuity flourishes under extreme time pressure--for instance, a NASA team within hours comes up with a primitive but effective fix for the failing air filtration system aboard Apollo 13. But when creativity is under the gun, it usually ends up getting killed, the authors say. They recently took a close look at how people experience time pressure, collecting and analyzing more than 9,000 daily diary entries from individuals who were working on projects that required high levels of creativity and measuring their ability to innovate under varying levels of time pressure. The authors describe common characteristics of time pressure and outline four working environments under which creativity may or may not flourish. High-pressure days that still yield creativity are full of focus and meaningful urgency--people feel like they are on a mission. High-pressure days that yield no creativity lack such focus--people feel like they are on a treadmill, forced to switch gears often. On low-pressure days that yield creativity, people feel like they are on an expedition--exploring ideas rather than just identifying problems. And on low-pressure days that yield no creative thinking, people work on autopilot--doing their jobs without engaging too deeply. Managers should avoid extreme time pressure when possible; after all, complex cognitive processing takes time. For when they can't, the authors suggest ways to mollify its effects.

  5. Underlying mechanisms of transient luminous events: a review

    Directory of Open Access Journals (Sweden)

    V. V. Surkov


    Full Text Available Transient luminous events (TLEs occasionally observed above a strong thunderstorm system have been the subject of a great deal of research during recent years. The main goal of this review is to introduce readers to recent theories of electrodynamics processes associated with TLEs. We examine the simplest versions of these theories in order to make their physics as transparent as possible. The study is begun with the conventional mechanism for air breakdown at stratospheric and mesospheric altitudes. An electron impact ionization and dissociative attachment to neutrals are discussed. A streamer size and mobility of electrons as a function of altitude in the atmosphere are estimated on the basis of similarity law. An alternative mechanism of air breakdown, runaway electron mechanism, is discussed. In this section we focus on a runaway breakdown field, characteristic length to increase avalanche of runaway electrons and on the role played by fast seed electrons in generation of the runaway breakdown. An effect of thunderclouds charge distribution on initiation of blue jets and gigantic jets is examined. A model in which the blue jet is treated as upward-propagating positive leader with a streamer zone/corona on the top is discussed. Sprite models based on streamer-like mechanism of air breakdown in the presence of atmospheric conductivity are reviewed. To analyze conditions for sprite generation, thunderstorm electric field arising just after positive cloud-to-ground stroke is compared with the thresholds for propagation of positively/negatively charged streamers and with runway breakdown. Our own estimate of tendril's length at the bottom of sprite is obtained to demonstrate that the runaway breakdown can trigger the streamer formation. In conclusion we discuss physical mechanisms of VLF (very low frequency and ELF (extremely low frequency phenomena associated with sprites.

  6. City under the Ice

    DEFF Research Database (Denmark)

    Nielsen, Kristian Hvidtfelt

    conflict that gave impetus to the camp’s construction. Presented to the public as a scientific station and a technologically-advanced, under-ice extension of the American way of life, while situated in the titanic struggle between West and East, Camp Century took on a number of closed-world meanings...... military conflicts are taking place. Studying the wealth of public representations of Camp Century, established 1959-60 by the US Army 128 miles east of the Thule Air Base and often referred to as the “City under the Ice”, we find a sharp contrast between the domesticated interior and the superpower......: The public image of Camp Century was one of technological comfort and military-scientific control. Amidst the raging Cold War and up against the harsh environment, the construction of the camp would prove to the public that the combined forces of the US military-technology-science complex would prevail...

  7. Child abuse: underlying mechanisms


    Martínez, Gladys S.


    Exposure to traumatic stress during childhood, in the form of abuse or neglect, is related to an increased vulnerability resulting in the development of several pathologies, this relation has been confi rmed by epidemiological studies; however, the neural mechanisms underlying such abnormalities are still unknown. Most of the research done has focused on the effects in the infant, and only recently it has begun to focus on the neurobiological changes in the abusive parents. In this article, I...

  8. Poland under "Solidarity" Rule


    Stanislaw Wellisz


    The coalition cabinet in which Solidarity played a leading role, but which also included Communists and their allies, won Parliamentary approval on September 12, 1989. This coalition inherited from the Communists an economy in deep crisis: inflation was raging, shortages of virtually all goods were rampant, and the black market was all-pervasive. The new government pledged to restore the market economy. This paper discusses the economy under Solidarity rule, focusing on stabilization and the ...

  9. R gas under diaphragm


    Ramachar Sreevathsa, Maddibande; Melanta, Khyati


    Introduction: The most common cause of gas under diaphragm is hollow viscous perforation. In 10% of cases it can be due to rare causes, both abdominal and extra-abdominal, one of them being intra abdominal infection by gas forming organisms. Presentation of the case: A 51 year old male patient, a poorly controlled diabetic, presented with a second episode of severe pain abdomen and abdominal distention, with lower abdominal tenderness. Plain Xray of the abdomen in erect posture showed gas ...

  10. A comparison of conductive textile-based and silver/silver chloride gel electrodes in exercise electrocardiogram recordings. (United States)

    Marozas, Vaidotas; Petrenas, Andrius; Daukantas, Saulius; Lukosevicius, Arunas


    The goal of this study was to compare disposable silver/silver chloride and reusable conductive textile-based electrodes in electrocardiogram (ECG) signal monitoring during physical activity. The reusable electrodes were produced using thin silver-plated nylon 117/17 2-ply conductive thread (Statex Productions & Vertriebs GmbH, Bremen, Germany) sewed with a sewing machine on a chest belt. The disposable and reusable electrodes were compared in vivo according to ECG signal baseline drift, broadband electrode noise properties, and influence of electrode area to ECG signal morphology and frequency content. Twelve volunteers were included in this study. Electroconductive textile-based ECG electrodes produce significantly more noise in a very low frequency band (0-0.67 Hz) and not significantly less of broadband noise (0-250 Hz) than disposable silver/silver chloride electrodes. Decreasing area of textile electrodes decreases fidelity of registered ECG signals at low frequencies. Textile electrodes having adequate area can be used in more applications than only R-R interval monitoring. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Evaporation under vacuum condition

    International Nuclear Information System (INIS)

    Mizuta, Satoshi; Shibata, Yuki; Yuki, Kazuhisa; Hashizume, Hidetoshi; Toda, Saburo; Takase, Kazuyuki; Akimoto, Hajime


    In nuclear fusion reactor design, an event of water coolant ingress into its vacuum vessel is now being considered as one of the most probable accidents. In this report, the evaporation under vacuum condition is evaluated by using the evaporation model we have developed. The results show that shock-wave by the evaporation occurs whose behavior strongly depends on the initial conditions of vacuum. And in the case of lower initial pressure and temperature, the surface temp finally becomes higher than other conditions. (author)

  12. Optimizing production under uncertainty

    DEFF Research Database (Denmark)

    Rasmussen, Svend

    This Working Paper derives criteria for optimal production under uncertainty based on the state-contingent approach (Chambers and Quiggin, 2000), and discusses po-tential problems involved in applying the state-contingent approach in a normative context. The analytical approach uses the concept...... of state-contingent production functions and a definition of inputs including both sort of input, activity and alloca-tion technology. It also analyses production decisions where production is combined with trading in state-contingent claims such as insurance contracts. The final part discusses...

  13. Intercrops under coconut plantations

    International Nuclear Information System (INIS)

    Mahmud, Z.


    The successes of growing intercrops under coconut plantations are controlled by environmental factors which are influenced by the coconut growth and characters, interception of solar radiation, as well as the coconut space and system of planting. Assuming that soil fertility be able to be manipulated by certain treatments, then climatic factors become priority to be considered for selection of intercrops. Coconut palms grow well on areas of 500 m asl., 27-32 deg. C temperature, and 1,500-3,000 mm in annual rainfall with even distribution throughout the year. Each kind (tall, dwarf, hybrid) of coconut performs specific growth characters, mainly on its root system and canopy coverage, as well as general conditions due to its growth phase (young, productive, senile). Above such conditions greatly influence the kind of crops suitable for development under coconut trees. However space and system of coconut planting give various conditions of interception solar radiation to ground surface, which means by manipulating both space and system, environmental requirement is able to be achieved accordingly [in

  14. Skolegang under anbringelse

    DEFF Research Database (Denmark)

    Perthou, Anette; Dam Mortensøn, Marie; Andersen, Dines

    Børn og unge, der er anbragt uden for hjemmet, klarer sig ofte dårligt i skolen. Det er især på døgninstitutioner og socialpædagogiske opholdssteder, at børnene halter bagefter, og der er derfor behov for et øget fokus på skolegangen på disse institutioner. SFI har via kvalitative interview med...... ledere, pædagoger og lærere på otte institutioner samt tilknyttede medarbejdere fra den kommunale PPR undersøgt, hvilke forhold der har betydning for anbragte børns skolegang. Rapporten fokuserer dels på samarbejdet mellem de professionelle faggrupper, der er involveret i de anbragte børns og unges...

  15. Attractors under discretisation

    CERN Document Server

    Han, Xiaoying


    This work focuses on the preservation of attractors and saddle points of ordinary differential equations under discretisation. In the 1980s, key results for autonomous ordinary differential equations were obtained – by Beyn for saddle points and by Kloeden & Lorenz for attractors. One-step numerical schemes with a constant step size were considered, so the resulting discrete time dynamical system was also autonomous. One of the aims of this book is to present new findings on the discretisation of dissipative nonautonomous dynamical systems that have been obtained in recent years, and in particular to examine the properties of nonautonomous omega limit sets and their approximations by numerical schemes – results that are also of importance for autonomous systems approximated by a numerical scheme with variable time steps, thus by a discrete time nonautonomous dynamical system.

  16. Chilean economy under Pinochet

    Directory of Open Access Journals (Sweden)

    Libor Žídek


    Full Text Available Period of Pinochet rule in Chile is still in the centre of interest of many experts. This article concentrates (mostly on the economic side of the military rule. Pinochet took responsibility for the country in situation near to economic collapse caused by policy of the previous – Allendeęs government. The new government after the coup dęétat in 1973 had to stabilize economy. Soldiers at the same time start to implement economic reforms that improved the long run ability of the economy to grow. The economic uplift was interrupted by debt crisis at the beginning of 1980s. Pinochetęs government was able to deal with these obstacles and at the end passed the economy to the democratic government (at the end of 1980s in good shape. The following positive development in the 1990s is thus based on the foundations built under the military rule.

  17. A life under pressure

    DEFF Research Database (Denmark)

    Jacobsen, Jens Christian Brings; von Holstein-Rathlou, Niels-Henrik


    Microvessels live 'a life under pressure' in several ways. In a literal sense, vessels of the microcirculation are exposed to high levels of stress caused primarily by the intravascular pressure head. In a figurative sense, the individual vessel and the microvascular network as a whole must...... continuously strive to meet the changing demands of the surrounding tissue. The 'principle of optimal operation' as formulated by Y. C. Fung states that living tissues adapts structurally through remodelling and growth until a level of tensile and compressive stresses is reached at which tissue performance...... stress component has a huge impact on the state of the vascular wall. It is involved as a unifying factor on vastly different timescales in processes as diverse as acute regulation of vessel diameter, structural vessel remodelling and growth or atrophy of the vascular wall. The aim of this Mini...

  18. Calibration Under Uncertainty.

    Energy Technology Data Exchange (ETDEWEB)

    Swiler, Laura Painton; Trucano, Timothy Guy


    This report is a white paper summarizing the literature and different approaches to the problem of calibrating computer model parameters in the face of model uncertainty. Model calibration is often formulated as finding the parameters that minimize the squared difference between the model-computed data (the predicted data) and the actual experimental data. This approach does not allow for explicit treatment of uncertainty or error in the model itself: the model is considered the %22true%22 deterministic representation of reality. While this approach does have utility, it is far from an accurate mathematical treatment of the true model calibration problem in which both the computed data and experimental data have error bars. This year, we examined methods to perform calibration accounting for the error in both the computer model and the data, as well as improving our understanding of its meaning for model predictability. We call this approach Calibration under Uncertainty (CUU). This talk presents our current thinking on CUU. We outline some current approaches in the literature, and discuss the Bayesian approach to CUU in detail.

  19. Politics Under Electronic Simultaneity

    Directory of Open Access Journals (Sweden)

    Valery P. Terin


    Full Text Available In contradistinction to the book and the other typographic products, the electronic media operates on a 24-hour-a-day basis evoking simultaneity as the guiding mode of perception and thinking for all those under its influence. The discovery of this fact manifested itself in the formation and development of the managerial technologies operating by means of the electronic information environment and following the principle of simultaneity in the first place. Thus, at the end of the 1960s already the election campaigns in the U.S.A. began to operate on the basis of the final cause as the guiding principle of the country's mass consciousness motivating to carry out each particular event as if already rejoicing at the victory. With this in mind, there emerged a problem of applying this approach with its enormous managerial potential elsewhere. To add, simultaneity as a norm of perception and thinking turned out to be increasingly important with the advent of the electrical telegraph and the press relying on its short disconnected messages instantaneously arriving from all parts of the world. All the other media, which emerged in the wake of this development, has served to fortify this mode of thought as governing in the electronic information environment. The potential of the electronically operating global managerial technologies is quickly growing. The article also deals with the information overload and pattern recognition problem understood in managerial terms as well as mythologization and demythologization processes as they are necessitated by the electronic media coverage worldwide.

  20. Undersøgelsesdesign

    DEFF Research Database (Denmark)

    Hansbøl, Mikala


    Delrapport fra LUG-projektet, delprojekt A - Uddannelsesinstitutionelle Grænser. I 2014 udvikler og forsker UCSJ og RUC i en gratis og fleksibel måde at udbyde uddannelse på, inspireret af flere universiteter i USA – via MOOCs (Multiple Open Online Courses). MOOC-projektet er en del af et større...... innovationsprojekt “Læring Uden Grænser” - støttet af den Den Europæiske Fond for Regionaludvikling. Projektet undersøger hvordan digitale teknologier og nye koblinger i form af netværk- og institutionssamarbejde kan mindske grænser for læring i Region Sjælland. Den næste år udvikles og udbydes en række MOOCs, der...... skal generere og formidle ny viden om, hvordan MOOCs kan udvikles på måder, så også regionale hensyn tages. Projektet arbejder designbaseret og der vil derfor gennem input fra brugere, partnere, arrangerede workshops, og lignende foregå en løbende redesignproces. Projektet vil munde ud i en række...

  1. WHn under pressure

    International Nuclear Information System (INIS)

    Zaleski-Ejgierd, Patryk; Ashcroft, N W; Labet, Vanessa; Hoffmann, Roald; Strobel, Timothy A


    An initial observation of the formation of WH under pressure from W gaskets surrounding hydrogen in diamond anvil cells led to a theoretical study of tungsten hydride phases. At P = 1 atm no stoichiometry is found to be stable with respect to separation into the elements, but as the pressure is raised WH n (n = 1-6, 8) stoichiometries are metastable or stable. WH and WH 4 are calculated to be stable at P > 15 GPa, WH 2 becomes stable at P > 100 GPa and WH 6 at P > 150 GPa. In agreement with experiment, the structure computed for WH is anti-NiAs. WH 2 shares with WH a hexagonal arrangement of tungsten atoms, with hydrogen atoms occupying octahedral and tetrahedral holes. For WH 4 the W atoms are in a distorted fcc arrangement. As the number of hydrogens rises, the coordination of W by H increases correspondingly, leading to a twelve-coordinated W in WH 6 . In WH 8 H 2 units also develop. All of the hydrides considered should be metallic at high pressure, though the Fermi levels of WH 4 and WH 6 lie in a deep pseudogap. Prodded by these theoretical studies, experiments were then undertaken to seek phases other than WH, exploring a variety of experimental conditions that would favor further reaction. Though a better preparation and characterization of WH resulted, no higher hydrides have as yet been found. (paper)

  2. Memory dynamics under stress. (United States)

    Quaedflieg, Conny W E M; Schwabe, Lars


    Stressful events have a major impact on memory. They modulate memory formation in a time-dependent manner, closely linked to the temporal profile of action of major stress mediators, in particular catecholamines and glucocorticoids. Shortly after stressor onset, rapidly acting catecholamines and fast, non-genomic glucocorticoid actions direct cognitive resources to the processing and consolidation of the ongoing threat. In parallel, control of memory is biased towards rather rigid systems, promoting habitual forms of memory allowing efficient processing under stress, at the expense of "cognitive" systems supporting memory flexibility and specificity. In this review, we discuss the implications of this shift in the balance of multiple memory systems for the dynamics of the memory trace. Specifically, stress appears to hinder the incorporation of contextual details into the memory trace, to impede the integration of new information into existing knowledge structures, to impair the flexible generalisation across past experiences, and to hamper the modification of memories in light of new information. Delayed, genomic glucocorticoid actions might reverse the control of memory, thus restoring homeostasis and "cognitive" control of memory again.

  3. Strategy under uncertainty. (United States)

    Courtney, H; Kirkland, J; Viguerie, P


    At the heart of the traditional approach to strategy lies the assumption that by applying a set of powerful analytic tools, executives can predict the future of any business accurately enough to allow them to choose a clear strategic direction. But what happens when the environment is so uncertain that no amount of analysis will allow us to predict the future? What makes for a good strategy in highly uncertain business environments? The authors, consultants at McKinsey & Company, argue that uncertainty requires a new way of thinking about strategy. All too often, they say, executives take a binary view: either they underestimate uncertainty to come up with the forecasts required by their companies' planning or capital-budging processes, or they overestimate it, abandon all analysis, and go with their gut instinct. The authors outline a new approach that begins by making a crucial distinction among four discrete levels of uncertainty that any company might face. They then explain how a set of generic strategies--shaping the market, adapting to it, or reserving the right to play at a later time--can be used in each of the four levels. And they illustrate how these strategies can be implemented through a combination of three basic types of actions: big bets, options, and no-regrets moves. The framework can help managers determine which analytic tools can inform decision making under uncertainty--and which cannot. At a broader level, it offers executives a discipline for thinking rigorously and systematically about uncertainty and its implications for strategy.

  4. Contextuality under weak assumptions

    International Nuclear Information System (INIS)

    Simmons, Andrew W; Rudolph, Terry; Wallman, Joel J; Pashayan, Hakop; Bartlett, Stephen D


    The presence of contextuality in quantum theory was first highlighted by Bell, Kochen and Specker, who discovered that for quantum systems of three or more dimensions, measurements could not be viewed as deterministically revealing pre-existing properties of the system. More precisely, no model can assign deterministic outcomes to the projectors of a quantum measurement in a way that depends only on the projector and not the context (the full set of projectors) in which it appeared, despite the fact that the Born rule probabilities associated with projectors are independent of the context. A more general, operational definition of contextuality introduced by Spekkens, which we will term ‘probabilistic contextuality’, drops the assumption of determinism and allows for operations other than measurements to be considered contextual. Even two-dimensional quantum mechanics can be shown to be contextual under this generalised notion. Probabilistic noncontextuality represents the postulate that elements of an operational theory that cannot be distinguished from each other based on the statistics of arbitrarily many repeated experiments (they give rise to the same operational probabilities) are ontologically identical. In this paper, we introduce a framework that enables us to distinguish between different noncontextuality assumptions in terms of the relationships between the ontological representations of objects in the theory given a certain relation between their operational representations. This framework can be used to motivate and define a ‘possibilistic’ analogue, encapsulating the idea that elements of an operational theory that cannot be unambiguously distinguished operationally can also not be unambiguously distinguished ontologically. We then prove that possibilistic noncontextuality is equivalent to an alternative notion of noncontextuality proposed by Hardy. Finally, we demonstrate that these weaker noncontextuality assumptions are sufficient to prove


    Directory of Open Access Journals (Sweden)

    Hezi Aviram SHAYB


    Full Text Available Nobody is planning to fail, but many companies are failing because of lack of planning. Real business experience showed during the years that crisis can be prevented, avoided or limited. If detected in time, the risks associated with the crisis can be mitigated and the effects can be diminished, with the condition that the actions required are done fast, in a sharp and accurate manner. When it comes, a crisis brings an intense level of pressure and under these conditions there is no time or room for mistakes. Delays, losing focus and lack of planning will bring a company one step away from failure. The right way to deal with crisis, if required measures are not done in time, is to minimize the losses and reposition in the best way possible. Analysing the success stories of some of the biggest and strongest companies in the world, led to an important conclusion: the majority of these companies were in the situation to face huge crises which threatened their ability to survive in certain moments, on their way to success. With the right planning and by setting a proper organisational structure, the negative aspects of the crisis can be turned into benefits and opportunities for the company. The most critical challenge for management is to assess the level of exposure to risk of the company and identify the key points to focus on in order to overcome the crisis and create value. In order to set up a strong plan in dealing with crisis, a business organisation needs reliable, efficient and effective tools and this is what this article is all about.

  6. Approximate entropy and point correlation dimension of heart rate variability in healthy subjects

    DEFF Research Database (Denmark)

    Storella, R J; Wood, H W; Mills, K M


    The contribution of nonlinear dynamics to heart rate variability in healthy humans was examined using surrogate data analysis. Several measures of heart rate variability were used and compared. Heart rates were recorded for three hours and original data sets of 8192 R-R intervals created. For each...... original data set (n = 34), three surrogate data sets were made by shuffling the order of the R-R intervals while retaining their linear correlations. The difference in heart rate variability between the original and surrogate data sets reflects the amount of nonlinear structure in the original data set....... Heart rate variability was analyzed by two different nonlinear methods, point correlation dimension and approximate entropy. Nonlinearity, though under 10 percent, could be detected with both types of heart rate variability measures. More importantly, not only were the correlations between...

  7. Underlying Event Measurements at CMS

    CERN Document Server

    Gupta, Rajat


    Measurements of Underlying Event activity using proton-proton collision data collected by the CMS detector will be presented. To check the energy dependence of the underlying event activity, results are compared with previous measurements from different experiments at different centre-of-mass energies.

  8. Prevalence of Under Nutrition among Under Five Year Children in ...

    African Journals Online (AJOL)

    Nigeria. ... International Journal of Community Research ... The nutritional status of under-five children is a reflection of the health of children in the community and this forms the basis for the development of success–oriented interventional ...

  9. 電界砥粒制御技術を応用したスラリー配置制御技術による研磨・加工技術(<連載>機能性流体)


    赤上, 陽一; Yoichi, AKAGAMI; 秋田県産業技術総合研究センター


    Author has been developed a novel polishing method using functional fluids which were dispersed abrasives with silicone oil. This fluid shows active reciprocate motion between electrodes under AC electric field at very low frequency. We have proposed new polishing method to improve the surface roughness and to be shorten processing time for hard materials and cutting edge of small seize ball-end mill tool using oil based functional fluid. And we have obtained glass plate polishing method usin...

  10. Accurate, Automated Detection of Atrial Fibrillation in Ambulatory Recordings (United States)

    Linker, David T.


    Purpose A highly accurate, automated algorithm would facilitate cost-effective screening for asymptomatic atrial fibrillation. This study analyzed a new algorithm and compared to existing techniques. Methods The incremental benefit of each step in refinement of the algorithm was measured, and the algorithm was compared to other methods using the Physionet atrial fibrillation and normal sinus rhythm databases. Results When analyzing segments of 21 RR intervals or less, the algorithm had a significantly higher area under the receiver operating characteristic curve (AUC) than the other algorithms tested. At analysis segment sizes of up to 101 RR intervals, the algorithm continued to have a higher AUC than any of the other methods tested, although the difference from the second best other algorithm was no longer significant, with an AUC of 0.9992 with a 95% confidence interval (CI) of 0.9986–0.9998, versus 0.9986 (CI 0.9978–0.9994). With identical per-subject sensitivity, per-subject specificity of the current algorithm was superior to the other tested algorithms even at 101 RR intervals, with no false positives (CI 0.0%–0.8%) versus 5.3% false positives for the second best algorithm (CI 3.4–7.9%). Conclusions The described algorithm shows great promise for automated screening for atrial fibrillation by reducing false positives requiring manual review, while maintaining high sensitivity. PMID:26850411

  11. Heart rate-mediated blood pressure control in preterm fetal sheep under normal and hypoxic-ischemic conditions. (United States)

    Zwanenburg, Alex; Jellema, Reint K; Jennekens, Ward; Ophelders, Daan; Vullings, Rik; van Hunnik, Arne; van Pul, Carola; Bennet, Laura; Delhaas, Tammo; Kramer, Boris W; Andriessen, Peter


    The understanding of hypoxemia-induced changes in baroreflex function is limited and may be studied in a fetal sheep experiment before, during, and after standardized hypoxic conditions. Preterm fetal lambs were instrumented at 102 d gestation (term: 146 d). At 106 d, intrauterine hypoxia--ischemia was induced by 25 min of umbilical cord occlusion (UCO). Baroreflex-related fluctuations were calculated at 30-min intervals during the first week after UCO by transfer function (cross-spectral) analysis between systolic blood pressure (SBP) and R-R interval fluctuations, estimated in the low-frequency (LF, 0.04-0.15 Hz) band. LF transfer gain (baroreflex sensitivity) and delay (s) reflect the baroreflex function. Baseline did not differ in LF transfer gain and delay between controls and the UCO group. In controls, LF gain showed postnatal increase. By contrast, LF gain gradually decreased in the UCO group, resulting in significantly lower values 4-7 d after UCO. In the UCO group, LF delay increased and differed significantly from controls. Our results show that intrauterine hypoxia-ischemia results in reduced baroreflex sensitivity over a period of 7 d, indicating limited efficacy to buffer BP changes by adapting heart rate. Cardiovascular dysregulation may augment already present cerebral damage after systemic hypoxia-ischemia in the reperfusion period.


    Monfredi, Oliver; Lyashkov, Alexey E; Johnsen, Anne-Berit; Inada, Shin; Schneider, Heiko; Wang, Ruoxi; Nirmalan, Mahesh; Wisloff, Ulrik; Maltsev, Victor A; Lakatta, Edward G; Zhang, Henggui; Boyett, Mark R


    Heart rate variability (beat-to-beat changes in the RR interval) has attracted considerable attention over the last 30+ years (PubMed currently lists >17,000 publications). Clinically, a decrease in heart rate variability is correlated to higher morbidity and mortality in diverse conditions, from heart disease to foetal distress. It is usually attributed to fluctuation in cardiac autonomic nerve activity. We calculated heart rate variability parameters from a variety of cardiac preparations (including humans, living animals, Langendorff-perfused heart and single sinoatrial nodal cell) in diverse species, combining this with data from previously published papers. We show that regardless of conditions, there is a universal exponential decay-like relationship between heart rate variability and heart rate. Using two biophysical models, we develop a theory for this, and confirm that heart rate variability is primarily dependent on heart rate and cannot be used in any simple way to assess autonomic nerve activity to the heart. We suggest that the correlation between a change in heart rate variability and altered morbidity and mortality is substantially attributable to the concurrent change in heart rate. This calls for re-evaluation of the findings from many papers that have not adjusted properly or at all for heart rate differences when comparing heart rate variability in multiple circumstances. PMID:25225208

  13. Frivillig og under eget ansvar

    DEFF Research Database (Denmark)

    Bang, Karin


    Ifølge Lou Andreas-Salomé drejer flere af Henrik Ibsens dramaer sig om problemet med at skabe balance mellem selvbefrielse og selvbegrænsning, og nøgleordene er: Frivillig og under eget ansvar....

  14. Refugee scientists under the spotlight (United States)

    Extance, Andy


    Thousands of people are forced to flee war-torn regions every year, but the struggles of scientists who have to leave their homeland often goes under the radar. Andy Extance reports on initiatives to help

  15. Logistics systems optimization under competition

    DEFF Research Database (Denmark)

    Choi, Tsan Ming; Govindan, Kannan; Ma, Lijun


    Nowadays, optimization on logistics and supply chain systems is a crucial and critical issue in industrial and systems engineering. Important areas of logistics and supply chain systems include transportation control, inventory management, and facility location planning. Under a competitive market...

  16. Graphene cantilever under Casimir force (United States)

    Derras-Chouk, Amel; Chudnovsky, Eugene M.; Garanin, Dmitry A.; Jaafar, Reem


    The stability of graphene cantilever under Casimir attraction to an underlying conductor is investigated. The dependence of the instability threshold on temperature and flexural rigidity is obtained. Analytical work is supplemented by numerical computation of the critical temperature above which the graphene cantilever irreversibly bends down and attaches to the conductor. The geometry of the attachment and exfoliation of the graphene sheet is discussed. It is argued that graphene cantilever can be an excellent tool for precision measurements of the Casimir force.

  17. Sustaining dry surfaces under water

    DEFF Research Database (Denmark)

    Jones, Paul R.; Hao, Xiuqing; Cruz-Chu, Eduardo R.


    not been investigated, and are critically important to maintain surfaces dry under water.In this work, we identify the critical roughness scale, below which it is possible to sustain the vapor phase of water and/or trapped gases in roughness valleys – thus keeping the immersed surface dry. Theoretical......Rough surfaces immersed under water remain practically dry if the liquid-solid contact is on roughness peaks, while the roughness valleys are filled with gas. Mechanisms that prevent water from invading the valleys are well studied. However, to remain practically dry under water, additional...... mechanisms need consideration. This is because trapped gas (e.g. air) in the roughness valleys can dissolve into the water pool, leading to invasion. Additionally, water vapor can also occupy the roughness valleys of immersed surfaces. If water vapor condenses, that too leads to invasion. These effects have...

  18. Equity valuation of Under Armour


    Diogo, Rafael Martins Ribeiro


    A dissertação aqui apresentada tem como objetivo apresentar uma avaliação para a Under Armour, - empresa que desenvolve a sua atividade na indústria do equipamento desportivo. A Under Armour representa um exemplo de empreendedorismo, determinação e excelência, personalizada pelo seu fundador e atual diretor executivo. Kevin Plank criou a empresa em 1996, com apenas 23 anos, através do desenvolvimento de um protótipo de uma t-shirt desportiva. Entretanto, a empresa já experienciou uma OPA e...

  19. Residual Liquefaction under Standing Waves

    DEFF Research Database (Denmark)

    Kirca, V.S. Ozgur; Sumer, B. Mutlu; Fredsøe, Jørgen


    This paper summarizes the results of an experimental study which deals with the residual liquefaction of seabed under standing waves. It is shown that the seabed liquefaction under standing waves, although qualitatively similar, exhibits features different from that caused by progressive waves....... The experimental results show that the buildup of pore-water pressure and the resulting liquefaction first starts at the nodal section and spreads towards the antinodal section. The number of waves to cause liquefaction at the nodal section appears to be equal to that experienced in progressive waves for the same...

  20. Regulating renewable resources under uncertainty

    DEFF Research Database (Denmark)

    Hansen, Lars Gårn

    Renewable natural resources (like water, fish and wildlife stocks, forests and grazing lands) are critical for the livelihood of millions of people and understanding how they can be managed efficiently is an important economic problem. I show how regulator uncertainty about different economic......) that a pro-quota result under uncertainty about prices and marginal costs is unlikely, requiring that the resource growth function is highly concave locally around the optimum and, 3) that quotas are always preferred if uncertainly about underlying structural economic parameters dominates. These results...

  1. Export Taxes under Bertrand Duopoly


    David Collie; Roger Clarke


    This article analyses export taxes in a Bertrand duopoly with product differentiation, where a home and a foreign firm both export to a third-country market. It is shown that the maximum-revenue export tax always exceeds the optimum-welfare export tax. In a Nash equilibrium in export taxes, the country with the low cost firm imposes the largest export tax. The results under Bertrand duopoly are compared with those under Cournot duopoly. It is shown that the absolute value of the export subsid...

  2. Investment under Uncertain Climate Policy

    DEFF Research Database (Denmark)

    Barradale, Merrill Jones


    This paper introduces the concept of payment probability as an important component of carbon risk (the financial risk associated with CO2 emissions under uncertain climate policy). In modeling power plant investment decisions, most existing literature uses the expected carbon price (e.g., the price...

  3. Underlying Mechanisms Affecting Institutionalisation of ...

    African Journals Online (AJOL)

    This paper discusses the underlying causal mechanisms that enabled or constrained institutionalisation of environmental education in 12 institutions in eight countries in southern Africa. The study was carried out in the context of the Southern Africa Development Community Regional Environmental Education Support ...

  4. Intumescent coatings under fast heating

    DEFF Research Database (Denmark)

    Nørgaard, Kristian Petersen; Dam-Johansen, Kim; Català, Pere


    Intumescent coatings are widely used to delay or minimise the destructive effects of fire. They are usually tested under conditions that simulate the relatively slow build-up of heat in a normal fire. Here, the effects of damage during a fire causing sudden heating of the coating were studied....

  5. Subsidized Capacity Investment under Uncertainty

    NARCIS (Netherlands)

    Wen, Xingang; Hagspiel, V.; Kort, Peter


    This paper studies how the subsidy support, e.g. price support and reimbursed investment cost support, affects the investment decision of a monopoly firm under uncertainty and analyzes the implications for social welfare. The analytical results show that the unconditional, i.e., subsidy support that

  6. Under pres for at tilgive

    DEFF Research Database (Denmark)

    Gade, Christian B.N.


    Efter afslutningen på apartheid i sydafrika etablerede landets nye parlament en sandheds- og forsoningskommission, hvor ofre for apartheid fik mulighed for at fortælle deres historier under offentlige høringer i kommissions komité for menneskerettighedskrænkelser. I løbet af kommissionens arbejde...

  7. Inclusive Education under Collectivistic Culture (United States)

    Futaba, Yasuko


    This paper addresses how inclusive education under collective culture is possible. Inclusive education, which more-or-less involves changing the current schools, has been denied, doubted or distorted by both policy-makers and practitioners of general and special education in Japan. Main reason for the setback in inclusive education can be…

  8. Underlying Mechanisms Affecting Institutionalisation of ...

    African Journals Online (AJOL)

    doctoral study and draws on critical realism as the ontological lens. Data analysis was done by means of a retroductive mode of inference, as articulated by Danermark, Ekström, Jakosben and Karlsson (2002). The paper demonstrates that there are a number of underlying causal mechanisms, which may enable or.

  9. Molecular mechanisms underlying bacterial persisters

    DEFF Research Database (Denmark)

    Maisonneuve, Etienne; Gerdes, Kenn


    All bacteria form persisters, cells that are multidrug tolerant and therefore able to survive antibiotic treatment. Due to the low frequencies of persisters in growing bacterial cultures and the complex underlying molecular mechanisms, the phenomenon has been challenging to study. However, recent...

  10. Strong evidence for changing fish reproductive phenology under climate warming on the Tibetan Plateau. (United States)

    Tao, Juan; He, Dekui; Kennard, Mark J; Ding, Chengzhi; Bunn, Stuart E; Liu, Chunlong; Jia, Yintao; Che, Rongxiao; Chen, Yifeng


    Phenological responses to climate change have been widely observed and have profound and lasting effects on ecosystems and biodiversity. However, compared to terrestrial ecosystems, the long-term effects of climate change on species' phenology are poorly understood in aquatic ecosystems. Understanding the long-term changes in fish reproductive phenology is essential for predicting population dynamics and for informing management strategies, but is currently hampered by the requirement for intensive field observations and larval identification. In this study, a very low-frequency sampling of juveniles and adults combined with otolith measurements (long axis length of the first annulus; LAFA) of an endemic Tibetan Plateau fish (Gymnocypris selincuoensis) was used to examine changes in reproductive phenology associated with climate changes from the 1970s to 2000s. Assigning individual fish to their appropriate calendar year class was assisted by dendrochronological methods (crossdating). The results demonstrated that LAFA was significantly and positively associated with temperature and growing season length. To separate the effects of temperature and the growing season length on LAFA growth, measurements of larval otoliths from different sites were conducted and revealed that daily increment additions were the main contributor (46.3%), while temperature contributed less (12.0%). Using constructed water-air temperature relationships and historical air temperature records, we found that the reproductive phenology of G. selincuoensis was strongly advanced in the spring during the 1970s and 1990s, while the increased growing season length in the 2000s was mainly due to a delayed onset of winter. The reproductive phenology of G. selincuoensis advanced 2.9 days per decade on average from the 1970s to 2000s, and may have effects on recruitment success and population dynamics of this species and other biota in the ecosystem via the food web. The methods used in this study

  11. Practice research under changing conditions

    DEFF Research Database (Denmark)

    Dreier, Ole

    particularly important in unraveling what is glossed over or reinterpreted beyond recognition. Doing so helps putting psychology back on its feet. But practice research was developed under other social, political and professional conditions and under other regimes of knowledge than we find today where...... research in critical psychology is based on a science of the subject – as opposed to the science of control dominating psychology. Of course, projects involve many subjects with diverse perspectives on the issues at hand. Descriptions of practices from subject positions previously considered negligible......The tradition of practice research emerged in critical psychology in Germany and Denmark about twenty-five years ago. It emphasizes the relevance of knowledge - above all knowledge for change - by researching exemplary scopes of possibilities for agents in particular kinds of situations. A key...

  12. Modelling microstructural evolution under irradiation

    International Nuclear Information System (INIS)

    Tikare, V.


    Microstructural evolution of materials under irradiation is characterised by some unique features that are not typically present in other application environments. While much understanding has been achieved by experimental studies, the ability to model this microstructural evolution for complex materials states and environmental conditions not only enhances understanding, it also enables prediction of materials behaviour under conditions that are difficult to duplicate experimentally. Furthermore, reliable models enable designing materials for improved engineering performance for their respective applications. Thus, development and application of mesoscale microstructural model are important for advancing nuclear materials technologies. In this chapter, the application of the Potts model to nuclear materials will be reviewed and demonstrated, as an example of microstructural evolution processes. (author)

  13. Nano controllers characterization under radiation

    International Nuclear Information System (INIS)

    Bezerra, F.; Barde, S.; Carayon, J.L.; Sarthou, M.


    4 commercial nano-controllers (PIC16LC84, PIC16C73A, PIC16C76 and ST62E25) from MICROCHIP and SGS-Thomson have been characterized under heavy-ions, protons and total dose. The preliminary results show that PIC16LC84 has to be banned from the selection because it can not sustain high cumulated dose (its Idd begins to shift at 6 krads) and that its E 2 PROM code memory is too sensitive to SEU (single event upset). The 3 PICs have been tested with heavy-ions, the results show that they are sensible to upsets and latch-up, nevertheless no latch-up has been observed under proton irradiation. The sensitivity to latch-up does not matter a lot because PICs consume very little and it is planned to implement them in a tolerant design. (A.C.)



    Tănase Alin-Eliodor; Calotă Traian-Ovidiu


    This article is focuses on accounting consolidation techniques and the preparation of consolidation worksheets for the components of financial statements (statement of comprehensive income, statement of changes in equity, and financial position). The presented group includes parent company, two subsidiaries (only one fully controlled by the parent company) and a jointly controlled entity. The financial statements are presented under the following standards IFRS 3 Business Combination, IAS 27 ...

  15. Chemical model reduction under uncertainty

    KAUST Repository

    Najm, Habib


    We outline a strategy for chemical kinetic model reduction under uncertainty. We present highlights of our existing deterministic model reduction strategy, and describe the extension of the formulation to include parametric uncertainty in the detailed mechanism. We discuss the utility of this construction, as applied to hydrocarbon fuel-air kinetics, and the associated use of uncertainty-aware measures of error between predictions from detailed and simplified models.

  16. Tort law under oligopolistic competition


    Mondello, Gérard; Salies, Evens


    This article extends the unilateral accident standard model to allow for Cournot competition. Assuming risk-neutrality for the regulator and injurers, it analyzes three liability regimes: strict liability, negligence rule, and strict liability with administrative authorization or permits systems. Under competition the equivalence between negligence rule and strict liability no longer holds, and negligence insures a better level of social care. However, enforcing both a permit system and ...

  17. Analytical methods under emergency conditions

    International Nuclear Information System (INIS)

    Sedlet, J.


    This lecture discusses methods for the radiochemical determination of internal contamination of the body under emergency conditions, here defined as a situation in which results on internal radioactive contamination are needed quickly. The purpose of speed is to determine the necessity for medical treatment to increase the natural elimination rate. Analytical methods discussed include whole-body counting, organ counting, wound monitoring, and excreta analysis. 12 references

  18. Ultrasonic sludge pretreatment under pressure. (United States)

    Le, Ngoc Tuan; Julcour-Lebigue, Carine; Delmas, Henri


    The objective of this work was to optimize the ultrasound (US) pretreatment of sludge. Three types of sewage sludge were examined: mixed, secondary and secondary after partial methanisation ("digested" sludge). Thereby, several main process parameters were varied separately or simultaneously: stirrer speed, total solid content of sludge (TS), thermal operating conditions (adiabatic vs. isothermal), ultrasonic power input (PUS), specific energy input (ES), and for the first time external pressure. This parametric study was mainly performed for the mixed sludge. Five different TS concentrations of sludge (12-36 g/L) were tested for different values of ES (7000-75,000 kJ/kgTS) and 28 g/L was found as the optimum value according to the solubilized chemical oxygen demand in the liquid phase (SCOD). PUS of 75-150 W was investigated under controlled temperature and the "high power input - short duration" procedure was the most effective at a given ES. The temperature increase in adiabatic US application significantly improved SCOD compared to isothermal conditions. With PUS of 150 W, the effect of external pressure was investigated in the range of 1-16 bar under isothermal and adiabatic conditions for two types of sludge: an optimum pressure of about 2 bar was found regardless of temperature conditions and ES values. Under isothermal conditions, the resulting improvement of sludge disintegration efficacy as compared to atmospheric pressure was by 22-67% and 26-37% for mixed and secondary sludge, respectively. Besides, mean particle diameter (D[4,3]) of the three sludge types decreased respectively from 408, 117, and 110 μm to about 94-97, 37-42, and 36-40 μm regardless of sonication conditions, and the size reduction process was much faster than COD extraction. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. 16 MW under the seas

    International Nuclear Information System (INIS)

    Mary, Olivier


    This article presents the Nemo project (Nemo stands for New Energy for Martinique and Overseas) and its precursor project, Ner 300, developed in cooperation between Akuo Energy and DCNS, and which is financed by the European Bank for Investment. These projects aim at exploiting sea thermal energy. Ner 300 will exploit the 20 degree difference between surface waters (25 C) and deep waters (5 C at 1.000 m under sea level). The article evokes works performed by DCNS to develop a prototype near the Reunion Island. The principle and operation are briefly described, and technological challenges are outlined

  20. Cellulose conversion under heterogeneous catalysis. (United States)

    Dhepe, Paresh L; Fukuoka, Atsushi


    In view of current problems such as global warming, high oil prices, food crisis, stricter environmental laws, and other geopolitical scenarios surrounding the use of fossil feedstocks and edible resources, the efficient conversion of cellulose, a non-food biomass, into energy, fuels, and chemicals has received much attention. The application of heterogeneous catalysis could allow researchers to develop environmentally benign processes that lead to selective formation of value-added products from cellulose under relatively mild conditions. This Minireview gives insight into the importance of biomass utilization, the current status of cellulose conversion, and further transformation of the primary products obtained.


    Directory of Open Access Journals (Sweden)



    Full Text Available Phytoremediation is a technique that has been used with increasing frequency to decontaminate soils treated with herbicides that have long - term residual effects, such as sulfentrazone. The goal was to assess phytoremediation of the herbicide sulfentrazone under field conditions by the species Canavalia ensiformis and Crotalaria juncea . The treatments consisted of combinations of the plant species C. ensiformis and C. juncea plus a control treatment (with manual weeding and four doses of the herbicide sulfentrazone. The experimental design used herein was a split - plot randomized block design with four replicates per subplot. The treatments were kept in the field for 75 days. After this period, the experimental area was again furrowed and fertilized, considering the requirements for Pennisetum glaucum , a plant used as an indicator of the presence of sulfentrazone. Thirty - four days after sowing pearl millet, the fresh and dry shoot masses of the plants were assessed. At the end of the cycle, the plant height, stem diameter, internode length, number of leaves, number of panicles, and fresh and dry panicle masses were determined. Previous cultivation of phytoremediation species C. ensiformis and C. juncea promotes sulfentrazone remediation. C. ensiformis is the most efficient species for the decontamination of the herbicide sulfentrazone under field conditions.

  2. Haldane model under nonuniform strain (United States)

    Ho, Yen-Hung; Castro, Eduardo V.; Cazalilla, Miguel A.


    We study the Haldane model under strain using a tight-binding approach, and compare the obtained results with the continuum-limit approximation. As in graphene, nonuniform strain leads to a time-reversal preserving pseudomagnetic field that induces (pseudo-)Landau levels. Unlike a real magnetic field, strain lifts the degeneracy of the zeroth pseudo-Landau levels at different valleys. Moreover, for the zigzag edge under uniaxial strain, strain removes the degeneracy within the pseudo-Landau levels by inducing a tilt in their energy dispersion. The latter arises from next-to-leading order corrections to the continuum-limit Hamiltonian, which are absent for a real magnetic field. We show that, for the lowest pseudo-Landau levels in the Haldane model, the dominant contribution to the tilt is different from graphene. In addition, although strain does not strongly modify the dispersion of the edge states, their interplay with the pseudo-Landau levels is different for the armchair and zigzag ribbons. Finally, we study the effect of strain in the band structure of the Haldane model at the critical point of the topological transition, thus shedding light on the interplay between nontrivial topology and strain in quantum anomalous Hall systems.

  3. Instant centre frequency at anaesthetic induction--a new way to analyse sympathovagal balance. (United States)

    de Souza Neto, Edmundo Pereira; Cerutti, Catherine; Loufoua, Joseph; Saroul, Christine; Chiari, Pascal; Custaud, Marc-Antoine; Lehot, Jean-Jacques


    The instant centre frequency (ICF) of RR interval has been proposed as a global index to analyse the sympathovagal interaction in the heart. The aim of this study was to assess the ICF during anaesthesia to test if it can reliably capture the neural control of the cardiovascular system. Twenty-four ASA II or III patients scheduled for cardiac surgery were included in the study. They were allocated in two groups: control, no treatment (group 1, n = 12), and beta-adrenergic blockade by atenolol (group 2, n = 12). Spectra of pulse interval series were computed with a time-frequency method and they were divided into: very low frequency (VLF, 0.000-0.040 Hz), low frequency (LF, 0.050-0.150 Hz) and high frequency (HF, 0.160-0.500 Hz). Normalized power was obtained by dividing the cumulative power within each frequency band (LF or HF) by the sum of LF and HF; the ratio of LF/HF was also calculated. Instant centre frequency is a time-varying parameter that the evolution along time of the gravity centrum of a local spectrum. All spectral indexes were recorded at the following time points: before induction, after induction and before intubation, during intubation, and after intubation. The atenolol group had lower normalized LF and the LF/HF ratio (P ICF was higher in atenolol group at all times. The ICF shifted towards HF frequency after induction and before intubation and shifted towards LF during intubation in both groups. The autonomic nervous system control on the heart through the interaction of sympathetic and parasympathetic reflex mechanisms could be studied by the ICF. The ICF may assess the autonomic cardiac modulation and may provide useful information for anaesthetic management.

  4. Increased first and second pulse harmonics in Tai Chi Chuan practitioners. (United States)

    Lu, Wan-An; Chen, Yung-Sheng; Kuo, Cheng-Deng


    Tai Chi Chuan (TCC) is known to be a good calisthenics for people. This study examined the relationship between pulse harmonics and autonomic nervous modulation in TCC practitioners. Power spectral measures of right pulse wave and heart rate variability (HRV) measures were compared between TCC practitioners and control subjects. Correlation analyses between pulse harmonics and HRV measures were performed using linear regression analysis. At baseline, the total power of pulse (TPp), powers of all individual pulse harmonics, normalized power of the 1(st) harmonics (nPh1) of TCC practitioners were greater, while the normalized power of the 4(th) pulse harmonics (nPh4) of TCC practitioners was smaller, than those of the controls. Similarly, the baseline standard deviation (SD(RR)), coefficient of variation (CV(RR)), and normalized high-frequency power (nHFP) of RR intervals were smaller, while the normalized very low-frequency power (nVLFP) and low-/high- frequency power ratio (LHR) were larger in the TCC practitioners. The TCC age correlated significantly and negatively with nPh1, and nearly significantly and negatively with nPh2 in the TCC practitioners. Thirty min after TCC exercise, the percentage changes in mRRI, SDRR, TP, VLFP were decreased, while the percentage changes in HR, ULFP, nLFP, and Ph2 were increased, relative to the controls. Correlation analysis shows that the %Ph2 correlates significantly and negatively with %mRRI and significantly and positively with %HR. The TCC practitioners had increased baseline total power of pulse and the 1(st) and 2(nd) pulse harmonics, and decreased power of the 4(th) pulse harmonics, along with decreased vagal modulation and increased sympathetic modulation. After TCC exercise, the power of the 2(nd) harmonics of TCC practitioners was increased which might be related to the increase in HR due to decreased vascular resistance after TCC exercise.

  5. Fisheries management under nutrient influence

    DEFF Research Database (Denmark)

    Hammarlund, Cecilia; Nielsen, Max; Waldo, Staffan


    A fisheries management model that identifies the economic optimal management of fisheries under the influence of nutrients is presented. The model starts from the idea that growth in fish biomass increases with increasing availability of nutrients owing to higher food availability up to a peak......, after which growth falls due to eutrophication. The model is applied to Swedish and Danish cod fisheries in the Western Baltic Sea and identifies the welfare contribution of the fisheries, measured as the sum of resource rent and producer surplus. In 2010, the welfare contribution was −28......% of the landing value. Maximizing the model with respect to effort alone and additionally over nitrogen concentration increases the contribution to 11% of the landing value in 2010. The analysis shows that the welfare effect of reducing fishing effort through management reforms is large, but that the effect...

  6. Granular gases under extreme driving (United States)

    Kang, W.; Machta, J.; Ben-Naim, E.


    We study inelastic gases in two dimensions using event-driven molecular-dynamics simulations. Our focus is the nature of the stationary state attained by rare injection of large amounts of energy to balance the dissipation due to collisions. We find that under such extreme driving, with the injection rate much smaller than the collision rate, the velocity distribution has a power-law high-energy tail. The numerically measured exponent characterizing this tail is in excellent agreement with predictions of kinetic theory over a wide range of system parameters. We conclude that driving by rare but powerful energy injection leads to a well-mixed gas and constitutes an alternative mechanism for agitating granular matter. In this distinct nonequilibrium steady state, energy cascades from large to small scales. Our simulations also show that when the injection rate is comparable with the collision rate, the velocity distribution has a stretched exponential tail.

  7. Precise object tracking under deformation

    International Nuclear Information System (INIS)

    Saad, M.H


    The precise object tracking is an essential issue in several serious applications such as; robot vision, automated surveillance (civil and military), inspection, biomedical image analysis, video coding, motion segmentation, human-machine interface, visualization, medical imaging, traffic systems, satellite imaging etc. This frame-work focuses on the precise object tracking under deformation such as scaling , rotation, noise, blurring and change of illumination. This research is a trail to solve these serious problems in visual object tracking by which the quality of the overall system will be improved. Developing a three dimensional (3D) geometrical model to determine the current pose of an object and predict its future location based on FIR model learned by the OLS. This framework presents a robust ranging technique to track a visual target instead of the traditional expensive ranging sensors. The presented research work is applied to real video stream and achieved high precession results.

  8. Physicists' Forced Migrations under Hitler (United States)

    Beyerchen, Alan


    When the Nazis came to power in early 1933 they initiated formal and informal measures that forced Jews and political opponents from public institutions such as universities. Some physicists retired and others went into industry, but most emigrated. International communication and contact made emigration a viable option despite the desperate economic times in the Great Depression. Another wave of emigrations followed the annexation of Austria in 1938. Individual cases as well as general patterns of migration and adaptation to new environments will be examined in this presentation. One important result of the forced migrations was that many of the physicists expelled under Hitler played important roles in strengthening physics elsewhere, often on the Allied side in World War II.

  9. Rock strength under explosive loading

    International Nuclear Information System (INIS)

    Rimer, N.; Proffer, W.


    This presentation emphasizes the importance of a detailed description of the nonlinear deviatoric (strength) response of the surrounding rock in the numerical simulation of underground nuclear explosion phenomenology to the late times needed for test ban monitoring applications. We will show how numerical simulations which match ground motion measurements in volcanic tuffs and in granite use the strength values obtained from laboratory measurements on small core samples of these rocks but also require much lower strength values after the ground motion has interacted with the rock. The underlying physical mechanisms for the implied strength reduction are not yet well understood, and in fact may depend on the particular rock type. However, constitutive models for shock damage and/or effective stress have been used successfully at S-Cubed in both the Geophysics Program (primarily for DARPA) and the Containment Support Program (for DNA) to simulate late time ground motions measured at NTS in many different rock types

  10. Theory buried under heavy description

    Directory of Open Access Journals (Sweden)

    Vivian B. Martin Ph.D.


    Full Text Available In journalism when a reporter puts the main news or point of the story deep down in the text, we say she’s buried the lead, the lead being the main point of the story and usually the first paragraph. In Children in Genocide: extreme traumatization and affect regulation, psychoanalyst Suzanne Kaplan buries her theory. Her study of the after effects of trauma among Holocaust survivors who were children during their persecution and survivors of atrocities during the Rwandan atrocities of the 1990s, is filled with highly descriptive material from the many interviews that serve as data. An interesting grounded theory is peeking out from under all the disciplinary discourse and historical background one must read through to get to what grounded theory readers will consider the juicy parts: concepts on affect regulation in trauma survivors.

  11. Component processes underlying future thinking. (United States)

    D'Argembeau, Arnaud; Ortoleva, Claudia; Jumentier, Sabrina; Van der Linden, Martial


    This study sought to investigate the component processes underlying the ability to imagine future events, using an individual-differences approach. Participants completed several tasks assessing different aspects of future thinking (i.e., fluency, specificity, amount of episodic details, phenomenology) and were also assessed with tasks and questionnaires measuring various component processes that have been hypothesized to support future thinking (i.e., executive processes, visual-spatial processing, relational memory processing, self-consciousness, and time perspective). The main results showed that executive processes were correlated with various measures of future thinking, whereas visual-spatial processing abilities and time perspective were specifically related to the number of sensory descriptions reported when specific future events were imagined. Furthermore, individual differences in self-consciousness predicted the subjective feeling of experiencing the imagined future events. These results suggest that future thinking involves a collection of processes that are related to different facets of future-event representation.

  12. Precise Object Tracking under Deformation

    International Nuclear Information System (INIS)

    Saad, M.H.


    The precise object tracking is an essential issue in several serious applications such as; robot vision, automated surveillance (civil and military), inspection, biomedical image analysis, video coding, motion segmentation, human-machine interface, visualization, medical imaging, traffic systems, satellite imaging etc. This framework focuses on the precise object tracking under deformation such as scaling, rotation, noise, blurring and change of illumination. This research is a trail to solve these serious problems in visual object tracking by which the quality of the overall system will be improved. Developing a three dimensional (3D) geometrical model to determine the current pose of an object and predict its future location based on FIR model learned by the OLS. This framework presents a robust ranging technique to track a visual target instead of the traditional expensive ranging sensors. The presented research work is applied to real video stream and achieved high precession results. xiiiThe precise object tracking is an essential issue in several serious applications such as; robot vision, automated surveillance (civil and military), inspection, biomedical image analysis, video coding, motion segmentation, human-machine interface, visualization, medical imaging, traffic systems, satellite imaging etc. This framework focuses on the precise object tracking under deformation such as scaling, rotation, noise, blurring and change of illumination. This research is a trail to solve these serious problems in visual object tracking by which the quality of the overall system will be improved. Developing a three dimensional (3D) geometrical model to determine the current pose of an object and predict its future location based on FIR model learned by the OLS. This framework presents a robust ranging technique to track a visual target instead of the traditional expensive ranging sensors. The presented research work is applied to real video stream and achieved high

  13. Nutrition security under extreme events (United States)

    Martinez, A.


    Nutrition security under extreme events. Zero hunger being one of the Sustainable Development Goal from the United Nations, food security has become a trending research topic. However extreme events impact on global food security is not yet 100% understood and there is a lack of comprehension of the underlying mechanisms of global food trade and nutrition security to improve countries resilience to extreme events. In a globalized world, food is still a highly regulated commodity and a strategic resource. A drought happening in a net food-exporter will have little to no effect on its own population but the repercussion on net food-importers can be extreme. In this project, we propose a methodology to describe and quantify the impact of a local drought to human health at a global scale. For this purpose, nutrition supply and global trade data from FAOSTAT have been used with domestic food production from national agencies and FAOSTAT, global precipitation from the Climate Research Unit and health data from the World Health Organization. A modified Herfindahl-Hirschman Index (HHI) has been developed to measure the level of resilience of one country to a drought happening in another country. This index describes how a country is dependent of importation and how diverse are its importation. Losses of production and exportation due to extreme events have been calculated using yield data and a simple food balance at country scale. Results show that countries the most affected by global droughts are the one with the highest dependency to one exporting country. Changes induced by droughts also disturbed their domestic proteins, fat and calories supply resulting most of the time in a higher intake of calories or fat over proteins.

  14. Image annotation under X Windows (United States)

    Pothier, Steven


    A mechanism for attaching graphic and overlay annotation to multiple bits/pixel imagery while providing levels of performance approaching that of native mode graphics systems is presented. This mechanism isolates programming complexity from the application programmer through software encapsulation under the X Window System. It ensures display accuracy throughout operations on the imagery and annotation including zooms, pans, and modifications of the annotation. Trade-offs that affect speed of display, consumption of memory, and system functionality are explored. The use of resource files to tune the display system is discussed. The mechanism makes use of an abstraction consisting of four parts; a graphics overlay, a dithered overlay, an image overly, and a physical display window. Data structures are maintained that retain the distinction between the four parts so that they can be modified independently, providing system flexibility. A unique technique for associating user color preferences with annotation is introduced. An interface that allows interactive modification of the mapping between image value and color is discussed. A procedure that provides for the colorization of imagery on 8-bit display systems using pixel dithering is explained. Finally, the application of annotation mechanisms to various applications is discussed.

  15. Noise exposure under hyperbaric conditions

    Energy Technology Data Exchange (ETDEWEB)



    Objective evidence exists that divers demonstrate a hearing deficit greater than would be expected from ageing effects alone. Deafness in divers may be caused by a number of factors other than exposure to excessive noise levels, eg barotrauma, ear infection etc. This review concentrates on the concern that exposure of commercial divers to noise while at work may cause a hearing deficit. Sound pressure levels recorded both underwater and in diving chambers often exceed those allowable to workers onshore. However, the sound perceived by the diver is modified both in amplitude and in frequency when he is either underwater or in pressurised chambers. Broadly the effect of this modification is to attenuate the sound and thus offer some protection from high noise levels. The degree of attentuation varies with the frequency of the sound, however it is also possible under specific conditions associated with gas density for the sensitivity to particular frequencies to be amplified above that for normal atmospheric air. The levels of sound observed from some underwater tools are of concern even after allowing for a significant de-sensitisation of the divers` hearing. Reports of tinnitus and temporary hearing loss following a dive are sure signs that the noise levels have been harmful. It is not possible at present to describe risk criteria for hearing damage due to noise exposure associated with diving. (author)

  16. Reliability analysis under epistemic uncertainty

    International Nuclear Information System (INIS)

    Nannapaneni, Saideep; Mahadevan, Sankaran


    This paper proposes a probabilistic framework to include both aleatory and epistemic uncertainty within model-based reliability estimation of engineering systems for individual limit states. Epistemic uncertainty is considered due to both data and model sources. Sparse point and/or interval data regarding the input random variables leads to uncertainty regarding their distribution types, distribution parameters, and correlations; this statistical uncertainty is included in the reliability analysis through a combination of likelihood-based representation, Bayesian hypothesis testing, and Bayesian model averaging techniques. Model errors, which include numerical solution errors and model form errors, are quantified through Gaussian process models and included in the reliability analysis. The probability integral transform is used to develop an auxiliary variable approach that facilitates a single-level representation of both aleatory and epistemic uncertainty. This strategy results in an efficient single-loop implementation of Monte Carlo simulation (MCS) and FORM/SORM techniques for reliability estimation under both aleatory and epistemic uncertainty. Two engineering examples are used to demonstrate the proposed methodology. - Highlights: • Epistemic uncertainty due to data and model included in reliability analysis. • A novel FORM-based approach proposed to include aleatory and epistemic uncertainty. • A single-loop Monte Carlo approach proposed to include both types of uncertainties. • Two engineering examples used for illustration.

  17. Something New Under the Sun (United States)

    Gavaghan, Helen

    In this, the first history of artifical satellites and their uses, Helen Gavaghan shows how the idea of putting an object in orbit around the earth changed from science fiction to indespensible technology in the twinkling of an eye. Thanks to satellites, we can now send data and images anywhere in the world in an instant. The satellite-based navigational system can pinpoint your exact location anywhere in the world; it is so precise that, from outer space, it can detect the sag on an airplane's wing. Focusing on three major areas of development - navigational satellites, communications, and weather observation and forecasting - Gavaghan tells the remarkable inside story of how obscure men and women, often laboring under strict secrecy, made the extraordinary scientific and technological discoveries needed to make these miracles happen. Written by a science journalist with support from the Sloane Foundation, the book describes the birth of the modern scientific era in the twentieth century, with creation of satellite technology. The narrative is part history - beginning with the Russian-U.S. contest with the launch of Sputnik; part politics, as scientists and visionary engineers compete for scarce funding that will bring their dreams to reality; partly the story of the singular and fascinating individuals who were present at the creation of our modern technological era.

  18. Pressure cylinders under fire condition

    Directory of Open Access Journals (Sweden)

    Jan Hora


    Full Text Available The presence of pressure cylinders under fire conditions significantly increases the risk rate for the intervening persons. It is considerably problematic to predict the pressure cylinders behaviour during heat exposition, its destruction progress and possible following explosion of the produced air–gas mixture because pressure cylinders and its environment generate a highly complicated dynamic system during an uncontrolled destruction. The large scale tests carried out by the Pilsen Fire and Rescue Department and the Rapid Response Unit of the Czech Republic Police in October 2012 and in May 2014 in the Military area Brdy and in the area of the former Lachema factory in Kaznějov had several objectives, namely, to record, qualify and quantify some of the aspects of an uncontrolled heat destruction procedure of an exposed pressure cylinder in an enclosed space and to qualify and describe the process of a controlled destruction of a pressure cylinder by shooting through it including basic tactical concepts. The article describes the experiments that were carried out.

  19. Decision Making Under Uncertain Categorization

    Directory of Open Access Journals (Sweden)

    Stephanie Ying-Fen Chen


    Full Text Available Two experiments investigated how category information is used in decision making under uncertainty and whether the framing of category information influences how it is used. Subjects were presented with vignettes in which the categorization of a critical item was ambiguous and were asked to choose among a set of actions with the goal of attaining the desired outcome for the main character in the story. The normative decision making strategy was to base the decision on all possible categories; however, research on a related topic, category-based induction, has found that people often only consider a single category when making predictions when categorization is uncertain. These experiments found that subjects tend to consider multiple categories when making decisions, but do so both when it is and is not appropriate, suggesting that use of multiple categories is not driven by an understanding of what categories are and are not relevant to the decision. Similarly, although a framing manipulation increased the rate of multiple-category use, it did so in situations in which multiple-category use was and was not appropriate.

  20. ATLAS: Now under new management

    CERN Multimedia

    Katarina Anthony


    On 1 March, the ATLAS Collaboration welcomed a new spokesperson, Dave Charlton (University of Birmingham), and two new deputy spokespersons, Thorsten Wengler (CERN) and Beate Heinemann (University of California, Berkeley and LBNL). The Bulletin takes a look at what’s in store for one of the world’s largest scientific collaborations.   ATLAS members at the 2010 collaboration meeting in Copenhagen. Image: Rune Johansen and Troels Petersen. ATLAS spokesperson Dave Charlton has seen the collaboration through countless milestones: from construction to start-up to the 4 July 2012 announcement, he’s been an integral part of the team. Now, after twelve years with the collaboration, Dave is moving into the main office for the next two years. “2012 was a landmark year for ATLAS,” says Dave. “We spent a lot of time in the limelight and, in many ways, all eyes are still on us. But with the shutdown now under way, our focus is ...

  1. Project Evaluation under Inflation Condition

    International Nuclear Information System (INIS)

    Hindy, M.; El Missiry, P.


    This paper analyzes the role of inflation in capital budgeting and attempts to introduce solutions to such implication in order to make the appropriate decision for the firm' stockholders under these circumstances. Inflation leads to biasness in evaluating the investment projects, due to its impact on the cash flow, the discount rate, the initial investment cost, and the depreciation. This paper has shown that the capital budgeting process is not neutral with respect to inflation, as the output prices will raise as well as the operating and capital expenditures will also be adjusted due to inflation. In addition, it has shown that it is reasonable to expect that the cost of capital will increase as a result of an increase in the real interest rate, the inflation premium, and the cost of equity. Of critical importance is the basis used in calculating the annual depreciation which may lead to the transfer of wealth from the investment projects to the government and will result in underestimating the net present value of the investment projects, if these depreciation charges is calculated based upon the historical values and not on the replacement cost of the fixed assets

  2. CANDU safety under severe accidents

    International Nuclear Information System (INIS)

    Snell, V.G.; Howieson, J.Q.; Alikhan, S.; Frescura, G.M.; King, F.; Rogers, J.T.; Tamm, H.


    The characteristics of the CANDU reactor relevant to severe accidents are set first by the inherent properties of the design, and second by the Canadian safety/licensing approach. The pressure-tube concept allows the separate, low-pressure, heavy-water moderator to act as a backup heat sink even if there is no water in the fuel channels. Should this also fail, the calandria shell itself can contain the debris, with heat being transferred to the water-filled shield tank around the core. Should the severe core damage sequence progress further, the shield tank and the concrete reactor vault significantly delay the challenge to containment. Furthermore, should core melt lead to containment overpressure, the containment behaviour is such that leaks through the concrete containment wall reduce the possibility of catastrophic structural failure. The Canadian licensing philosophy requires that each accident, together with failure of each safety system in turn, be assessed (and specified dose limits met) as part of the design and licensing basis. In response, designers have provided CANDUs with two independent dedicated shutdown systems, and the likelihood of Anticipated Transients Without Scram is negligible. Probabilistic safety assessment studies have been performed on operating CANDU plants, and on the 4 x 880 MW(e) Darlington station now under construction; furthermore a scoping risk assessment has been done for a CANDU 600 plant. They indicate that the summed severe core damage frequency is of the order of 5 x 10 -6 /year. 95 refs, 3 tabs

  3. CANDU safety under severe accidents

    International Nuclear Information System (INIS)

    Snell, V.G.; Howieson, J.Q.; Frescura, G.M.; King, F.; Rogers, J.T.; Tamm, H.


    The characteristics of the CANDU reactor relevant to severe accidents are set first by the inherent properties of the design, and second by the Canadian safety/licensing approach. Probabilistic safety assessment studies have been performed on operating CANDU plants, and on the 4 x 880 MW(e) Darlington station now under construction; furthermore a scoping risk assessment has been done for a CANDU 600 plant. They indicate that the summed severe core damage frequency is of the order of 5 x 10 -6 /year. CANDU nuclear plant designers and owner/operators share information and operational experience nationally and internationally through the CANDU Owners' Group (COG). The research program generally emphasizes the unique aspects of the CANDU concept, such as heat removal through the moderator, but it has also contributed significantly to areas generic to most power reactors such as hydrogen combustion, containment failure modes, fission product chemistry, and high temperature fuel behaviour. Abnormal plant operating procedures are aimed at first using event-specific emergency operating procedures, in cases where the event can be diagnosed. If this is not possible, generic procedures are followed to control Critical Safety Parameters and manage the accident. Similarly, the on-site contingency plans include a generic plan covering overall plant response strategy, and a specific plan covering each category of contingency

  4. German urologists under national socialism. (United States)

    Krischel, Matthis


    The first full-time professorship for urology at a German university was established in 1937 and in 1942, a rare teaching qualification (Habilitation) for urology was granted, both at the prestigious Berlin University. At the same time, nearly a third of all physicians who worked in the field of urology were classified as "non-Aryan" according to Nazi race laws and were forced out of their profession and their homeland. Many of them committed suicide or, if they refused to flee, were murdered in concentration camps. German urologists also contributed to compulsory sterilization of men according to the "law for the prevention of hereditarily diseased offspring" between 1934 and 1945. Historical sources on the history of urology in Nazi Germany were reviewed and analyzed. These include textbooks and medical journals from the 1930s and 1940s, as well as files from different state and university archives. For urologists, the changing political environment in Germany after 1933 offered possibilities to assert their personal and professional interests. Unfortunately, in many cases, moral principles were thrown overboard, and physicians advanced their own careers and the specialty of urology at the expense of their patients and their Jewish colleagues. Under national socialism, German urologists backed Nazi health and race policies and in exchange gained further professionalization for their specialty, including university positions and increased independence from surgery. Only in recent years has this chapter of German urology's past become a topic of debate among members of the professional society.

  5. EDITORIAL: High performance under pressure High performance under pressure (United States)

    Demming, Anna


    nanoelectromechanical systems. Researchers in China exploit the coupling between piezoelectric and semiconducting properties of ZnO in an optimised diode device design [6]. They used a Schottky rather than an ohmic contact to depress the off current. In addition they used ZnO nanobelts that have dominantly polar surfaces instead of [0001] ZnO nanowires to enhance the on current under the small applied forces obtained by using an atomic force microscopy tip. The nanobelts have potential for use in random access memory devices. Much of the success in applying piezoresistivity in device applications stems from a deepening understanding of the mechanisms behind the process. A collaboration of researchers in the USA and China have proposed a new criterion for identifying the carrier type of individual ZnO nanowires based on the piezoelectric output of a nanowire when it is mechanically deformed by a conductive atomic force microscopy tip in contact mode [7]. The p-type/n-type shell/core nanowires give positive piezoelectric outputs, while the n-type nanowires produce negative piezoelectric outputs. In this issue Zhong Lin Wang and colleagues in Italy and the US report theoretical investigations into the piezoresistive behaviour of ZnO nanowires for energy harvesting. The work develops previous research on the ability of vertically aligned ZnO nanowires under uniaxial compression to power a nanodevice, in particular a pH sensor [8]. Now the authors have used finite element simulations to study the system. Among their conclusions they find that, for typical geometries and donor concentrations, the length of the nanowire does not significantly influence the maximum output piezopotential because the potential mainly drops across the tip. This has important implications for low-cost, CMOS- and microelectromechanical-systems-compatible fabrication of nanogenerators. The simulations also reveal the influence of the dielectric surrounding the nanowire on the output piezopotential, especially for

  6. Vacuum mammotomy under ultrasound guidance

    International Nuclear Information System (INIS)

    Luczynska, E.; Kocurek, A.; Pawlik, T.; Aniol, J.; Herman, K.; Skotnicki, P.


    Breast ultrasound is a non-invasive method of breast examination. You can use it also for fine needle biopsy, core needle biopsy, vacuum mammotomy and for placing the '' wire '' before open surgical biopsy. 106 patients (105 women and 1 man) aged 20-71 years (mean age 46.9) were treated in Cancer Institute in Cracow by vacuum mammotomy under ultrasound guidance. The lesions found in ultrasonography were divided into three groups: benign lesions (BI RADS II), ambiguous lesions (BI RADS 0, III and IVa), and suspicious lesions (BI RADS IV B, IV C and V). Then lesions were qualified to vacuum mammotomy. According to USG, fibroadenoma or '' fibroadenoma-like '' lesions were found in 75 women, in 6 women complicated cysts, in 6 women cyst with dense fluid (to differentiate with FA), and in 19 patients undefined lesions. Fibroadenoma was confirmed in histopathology in 74% patients among patients with fibroadenoma or '' fibroadenoma-like '' lesions in ultrasound (in others also benign lesions were found). Among lesions undefined after ultrasound examination (total 27 patients) cancer was confirmed in 6 % (DCIS and IDC). In 6 patients with complicated cysts in ultrasound examination, histopathology confirmed fibroadenoma in 4 women, an intraductal lesion in 1 woman and inflamatory process in 1 woman. Also in 6 women with a dense cyst or fibroadenoma seen in ultrasound, histopathology confirmed fibroadenoma in 3 women and fibrosclerosis in 3 women. Any breast lesions undefined or suspicious after ultrasound examination should be verified. The method of verification or kind of operation of the whole lesion (vacuum mammotomy or '' wire '') depends on many factors, for example: lesion localization; lesion size; BI RADS category. (author)

  7. Superconducting critical temperature under pressure (United States)

    González-Pedreros, G. I.; Baquero, R.


    The present record on the critical temperature of a superconductor is held by sulfur hydride (approx. 200 K) under very high pressure (approx. 56 GPa.). As a consequence, the dependence of the superconducting critical temperature on pressure became a subject of great interest and a high number of papers on of different aspects of this subject have been published in the scientific literature since. In this paper, we calculate the superconducting critical temperature as a function of pressure, Tc(P), by a simple method. Our method is based on the functional derivative of the critical temperature with the Eliashberg function, δTc(P)/δα2F(ω). We obtain the needed coulomb electron-electron repulsion parameter, μ*(P) at each pressure in a consistent way by fitting it to the corresponding Tc using the linearized Migdal-Eliashberg equation. This method requires as input the knowledge of Tc at the starting pressure only. It applies to superconductors for which the Migdal-Eliashberg equations hold. We study Al and β - Sn two weak-coupling low-Tc superconductors and Nb, the strong coupling element with the highest critical temperature. For Al, our results for Tc(P) show an excellent agreement with the calculations of Profeta et al. which are known to agree well with experiment. For β - Sn and Nb, we found a good agreement with the experimental measurements reported in several works. This method has also been applied successfully to PdH elsewhere. Our method is simple, computationally light and gives very accurate results.

  8. Structural Damage Assessment under Uncertainty (United States)

    Lopez Martinez, Israel

    isolated based on the integration of sensitivity analysis and statistical sampling, which minimizes the occurrence of false-damage indication due to uncertainty. To perform diagnostic decision-making under uncertainty, an evidential reasoning approach for damage assessment is developed for addressing the possible imprecision in the damage localization results. The newly developed damage detection and localization techniques are applied and validated through both vibration test data from literature and in house laboratory experiments.

  9. Behaviour of uranium under irradiation

    International Nuclear Information System (INIS)

    Adda, Y.; Mustelier, J.P.; Quere, Y.; Commissariat a l'Energie Atomique, Fontenay-aux-Roses


    The main results obtained in a study of the formation of defects caused in uranium by fission at low temperature are reported. By irradiation at 20 K. it was possible to determine the number of Frenkel pairs produced by one fission. An analysis of the curves giving the variations in electrical resistivity shows the size of the displacement spikes and the mechanism of defect creation due to fission. Irradiations at 77 K gave additional information, showing behaviour differences in the case of recrystallised and of cold worked uranium. The diffusion of rare gases was studied using metal-rare gas alloys obtained by electrical discharge, and samples of irradiated uranium. Simple diffusion is only responsible for the release of the rare gases under vacuum in cases where the rare gas content is very low (very slightly irradiated U). On the other hand when the concentration is higher (samples prepared by electrical discharge) the gas is given off by the formation, growth and coalescence of bubbles; the apparent diffusion coefficient is then quite different from the true coefficient and cannot be used in calculations on swelling. The various factors governing the phenomenon of simple diffusion were examined. It was shown in particular that a small addition of molybdenum could reduce the diffusion coefficient by a factor of 100. The precipitation of gas in uranium (Kr), in silver (Kr) and in Al-Li alloy (He) have been followed by measurement of the crystal parameter and of the electrical resistivity, and by electron microscope examination of thin films. The important part played by dislocations in the generation and growth of bubbles has been demonstrated, and it has been shown also that precipitation of bubbles on the dislocation lattice could block the development of recrystallisation. The results of these studies were compared with observations made on the swelling of uranium and uranium alloys U Mo and U Nb strongly irradiated between 400 and 700 C. In the case of Cubic

  10. Science Underlying 2008 Nobel Prizes (United States)

    Caldwell, Bernadette A.


    JCE offers a wealth of materials for teaching and learning chemistry that you can explore online. In the list below, Bernadette Caldwell of the Editorial Staff suggests additional resources that are available through JCE for teaching the science behind some of the 2008 Nobel Prizes . Discovering and Applying the Chemistry of GFP The Royal Swedish Academy of Sciences awarded the 2008 Nobel Prize in Chemistry for the discovery and development of the green fluorescent protein, GFP to three scientists: Osamu Shimomura, Martin Chalfie, and Roger Y. Tsien. These scientists led the field in discovering and introducing a fluorescing protein from jellyfish into cells and genes under study, which allows researchers to witness biochemistry in action. Now tags are available that emit light in different colors, revealing myriad biological processes and their interactions simultaneously. Identifying HPV and HIV, HIV's Replication Cycle, and HIV Virus-Host Interactions The Nobel Assembly at Karolinska Institutet awarded the 2008 Nobel Prize in Medicine or Physiology for their discovery of human immunodeficiency virus (HIV) to two scientists: Françoise Barré-Sinoussi and Luc Montagnier; and for his discovery of human papilloma viruses [HPV] causing cervical cancer to one scientist, Harald zur Hausen. Diseases caused by these infectious agents significantly affect global health. While isolating and studying the virus, researchers discovered HIV is an uncommon retrovirus that infects humans and relies on the host to make its viral DNA, infecting and killing the host's white blood cells, ultimately destroying the immune systems of infected humans. Related Resources at JCE Online The Journal has published articles relating to GFP specifically, and more generally to fluorescing compounds applied to biochemistry. The Journal has also published an article and a video on protease inhibition—a strategy to suppress HIV's biological processes. With the video clips, an accompanying guide

  11. Open hemorrhoidectomy under local anesthesia for symptomatic ...

    African Journals Online (AJOL)

    standard treatment for prolapsed hemorrhoids. The procedure is commonly done under general or regional anesthesia. This study is aimed to assess the feasibility and tolerability of open – hemorrhoidectomy under local anaesthesia in our setting.

  12. Optimal taxation of exhaustible resource under monopoly

    International Nuclear Information System (INIS)

    Im, Jeong-Bin


    This paper deals with the problem of using taxes (or subsidies) to correct the inefficient resource allocation under monopoly. In this paper, the question raised is 'what would be the optimal tax on resource extraction under monopoly?' Ultimately, it is shown that taxes may be devised to generate price and extraction paths under monopoly that are identical to those under the competitive equilibrium. Tax policy can thus be used as an instrument for changing the distortionary resource allocation generated by the monopolist

  13. Drug discrimination under a concurrent schedule.


    Snodgrass, S H; McMillan, D E


    Three pigeons were trained to discriminate a 5.0 mg/kg dose of pentobarbital from saline under a two-key concurrent schedule with responding on the key associated with the presession injection, under both stimulus conditions, producing four times as many reinforcers as responding on the other key. This concurrent schedule resulted in approximately 70% responding to the higher reinforcement key under the pentobarbital stimulus and approximately 30% responding to that key under the saline stimu...

  14. Consistency of the MLE under mixture models


    Chen, Jiahua


    The large-sample properties of likelihood-based statistical inference under mixture models have received much attention from statisticians. Although the consistency of the nonparametric MLE is regarded as a standard conclusion, many researchers ignore the precise conditions required on the mixture model. An incorrect claim of consistency can lead to false conclusions even if the mixture model under investigation seems well behaved. Under a finite normal mixture model, for instance, the consis...

  15. Metal speciation under Rhizophora and Avicennia mangles


    Andrade, Regina Célia Bastos de; Patchineelam, Sambasiva Rao


    Speciation studies of Fe, Cr, Co, Ni and Cu on reactive fraction (adsorved on oxides, hydroxides, carbonates and clay minerals) and pyrite were performed in Avicennia schaueriana and Rhizophora mangle sediments from Amapá shoreline-Brazil. The soil under Avicennia showed a higher heavy metal concentration in reactive fraction than under Rhizophora. The soil under Rhizophora showed low heavy metal bioavailability, having an increasing association with pyrite across sediment section.

  16. Performance tracking under ARCS contracts. Directive

    International Nuclear Information System (INIS)


    The directive discusses the development of a non-resource intensive method for reporting performance based work allocation results under the ARCS (Alternative Remedial Contracting Strategy) contractors

  17. Exchange rate policy under sovereign default risk


    Schabert, Andreas


    We examine monetary policy options for a small open economy where sovereign default might occur due to intertemporal insolvency. Under interest rate policy and floating exchange rates the equilibrium is indetermined. Under a fixed exchange rate the equilibrium is uniquely determined and independent of sovereign default.

  18. Percutaneous nephrolithotripsy under assisted local anaesthesia for ...

    African Journals Online (AJOL)

    T.KH. Fathelbab

    Abstract. Objectives: The aim of the present study is to evaluate the feasibility and safety of performing PNL under local anesthesia in a selected group of patients who are at high risk for general anesthesia. Patients and methods: Forty seven patients underwent PNL under local anesthesia. There were 38 males.

  19. water infiltration, conductivity and runoff under fallow

    African Journals Online (AJOL)

    Measurements of runoff was done during the long rains of. 2003 and short rains of 2004. Infiltration was invariably higher under agroforestry systems (P<0.001) than sole cropping, particularly under Alnus and Calliandra systems. A similar pattern was observed for saturated hydraulic conductivity (Ksat), which was greater in ...

  20. Factors influencing immunisation coverage among children under ...

    African Journals Online (AJOL)

    Background This article explores the hypothesis that predisposing and enabling factors of households influence the vaccination status of the children under the age of five in Khartoum State, Sudan. Method The study was a cross-sectional survey among a representative sample of 410 male and female children under five ...

  1. Pavement behaviour under the super single tyre

    CSIR Research Space (South Africa)

    Viljoen, AW


    Full Text Available Pavement behaviour under the super single tyre (SST) was investigated and compared with that under a conventional dual tyre (CDT). Contact areas and contact pressures over a range of loading conditions were measured and compared. Two approaches were...

  2. Maximum likelihood estimation of exponential distribution under ...

    African Journals Online (AJOL)

    Maximum likelihood estimation of exponential distribution under type-ii censoring from imprecise data. ... Journal of Fundamental and Applied Sciences ... This paper deals with the estimation of exponential mean parameter under Type-II censoring scheme when the lifetime observations are fuzzy and are assumed to be ...

  3. Transformation kinetics of mixed polymeric substrates under ...

    African Journals Online (AJOL)

    Transformation kinetics of mixed polymeric substrates under transitory conditions by Aspergillus niger. ... Abstract. A mixture of polymeric substrates (simulating a complex wastewater) was transformed under sewer conditions and aerobiosis by Aspergillus niger in a tanks-in-series reactor at a hydraulic retention time of 14 h.

  4. Experiments were conducted under uniform flow

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Experiments were conducted under uniform flow: Experiments were conducted under uniform flow: Bed slopes: S = 0.13, 0.30, 0.38%. Sediments used: d50 = 0.95, 2.6, 4.1 mm. Experimental conditions were independent of relative submergence: Sh (= d50/h) < 0.1 ...

  5. Mechanical buckling of artery under pulsatile pressure. (United States)

    Liu, Qin; Han, Hai-Chao


    Tortuosity that often occurs in carotid and other arteries has been shown to be associated with high blood pressure, atherosclerosis, and other diseases. However the mechanisms of tortuosity development are not clear. Our previous studies have suggested that arteries buckling could be a possible mechanism for the initiation of tortuous shape but artery buckling under pulsatile flow condition has not been fully studied. The objectives of this study were to determine the artery critical buckling pressure under pulsatile pressure both experimentally and theoretically, and to elucidate the relationship of critical pressures under pulsatile flow, steady flow, and static pressure. We first tested the buckling pressures of porcine carotid arteries under these loading conditions, and then proposed a nonlinear elastic artery model to examine the buckling pressures under pulsatile pressure conditions. Experimental results showed that under pulsatile pressure arteries buckled when the peak pressures were approximately equal to the critical buckling pressures under static pressure. This was also confirmed by model simulations at low pulse frequencies. Our results provide an effective tool to predict artery buckling pressure under pulsatile pressure. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Capillary pressure studies under low gravity conditions. (United States)

    Kovalchuk, V I; Ravera, F; Liggieri, L; Loglio, G; Pandolfini, P; Makievski, A V; Vincent-Bonnieu, S; Krägel, J; Javadi, A; Miller, R


    For the understanding of short-time adsorption phenomena and high-frequency relaxations at liquid interfaces particular experimental techniques are needed. The most suitable method for respective studies is the capillary pressure tensiometry. However, under gravity conditions there are rather strong limitations, in particular due to convections and interfacial deformations. This manuscript provides an overview of the state of the art of experimental tools developed for short-time and high-frequency investigations of liquid drops and bubbles under microgravity. Besides the brief description of instruments, the underlying theoretical basis will be presented and limits of the applied methods under ground and microgravity conditions will be discussed. The results on the role of surfactants under highly dynamic conditions will be demonstrated by some selected examples studied in two space shuttle missions on Discovery in 1998 and Columbia in 2003. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Phase transitions in solids under high pressure

    CERN Document Server

    Blank, Vladimir Davydovich


    Phase equilibria and kinetics of phase transformations under high pressureEquipment and methods for the study of phase transformations in solids at high pressuresPhase transformations of carbon and boron nitride at high pressure and deformation under pressurePhase transitions in Si and Ge at high pressure and deformation under pressurePolymorphic α-ω transformation in titanium, zirconium and zirconium-titanium alloys Phase transformations in iron and its alloys at high pressure Phase transformations in gallium and ceriumOn the possible polymorphic transformations in transition metals under pressurePressure-induced polymorphic transformations in АIBVII compoundsPhase transformations in AIIBVI and AIIIBV semiconductor compoundsEffect of pressure on the kinetics of phase transformations in iron alloysTransformations during deformation at high pressure Effects due to phase transformations at high pressureKinetics and hysteresis in high-temperature polymorphic transformations under pressureHysteresis and kineti...

  8. Combustion of emulsified fuel droplets under microgravity (United States)

    Okajima, S.; Kanno, H.; Kumagai, S.

    Single-droplet experiments have been conducted under a zero-gravity condition in a freely falling chamber as a fundamental step of study on the spray combustion of hydrocarbon-water emulsified fuels. Such a behavior as the secondary micro-atomization was observed by taking schlieren photographs with a 35-mm movie camera installed on the falling assembly. Under zero gravity the emulsion droplet initiates steam discharge and puffing—that is, a mild atomization—at a time from ignition, but it does not lead to such a micro-explosion or disruption as is experienced under normal gravity. The apparent burning rate constant under zero gravity is about 30% smaller than that under normal gravity. These facts suggest that the internal convection in emulsion droplets plays an important role in causing the micro-explosion.

  9. Persistent sympathoexcitation long after submaximal exercise in subjects with and without coronary artery disease. (United States)

    Wang, Norman C; Chicos, Alexandru; Banthia, Smriti; Bergner, Daniel W; Lahiri, Marc K; Ng, Jason; Subacius, Haris; Kadish, Alan H; Goldberger, Jeffrey J


    There is an increased risk of cardiac events after exercise, which may, in part, be mediated by the sympathoexcitation that accompanies exercise. The duration and extent of this sympathoexcitation following moderate exercise is unknown, particularly in those with coronary artery disease (CAD). Twenty control subjects (mean age, 51 years) and 89 subjects with CAD (mean age, 58 years) underwent two 16-min bicycle exercise sessions followed by 30-45 min of recovery. Session 1 was performed under physiological conditions to peak workloads of 50-100 W. In session 2, parasympathetic blockade with atropine (0.04 mg/kg) was achieved at end exercise at the same workload as session 1. RR interval was continually recorded, and plasma catecholamines were measured at rest and selected times during exercise and recovery. Parasympathetic effect, measured as the difference in RR interval with and without atropine, did not differ between controls and CAD subjects in recovery. At 30 and 45 min of recovery, RR intervals were 12% and 9%, respectively, shorter than at rest. At 30 and 45 min of recovery, plasma norepinephrine levels were 15% and 12%, respectively, higher than at rest. A brief period of moderate exercise is associated with a prolonged period of sympathoexcitation extending >45 min into recovery and is quantitatively similar among control subjects and subjects with CAD, with or without left ventricular dysfunction. Parasympathetic reactivation occurs early after exercise and is also surprisingly quantitatively similar in controls and subjects with CAD. The role of these autonomic changes in precipitating cardiac events requires further evaluation.

  10. Clock frequency estimation under spontaneous emission (United States)

    Qin, Xi-Zhou; Huang, Jia-Hao; Zhong, Hong-Hua; Lee, Chaohong


    We investigate the quantum dynamics of a driven two-level system under spontaneous emission and its application in clock frequency estimation. By using the Lindblad equation to describe the system, we analytically obtain its exact solutions, which show three different regimes: Rabi oscillation, damped oscillation, and overdamped decay. From the analytical solutions, we explore how the spontaneous emission affects the clock frequency estimation. We find that under a moderate spontaneous emission rate, the transition frequency can still be inferred from the Rabi oscillation. Our results enable potential practical applications in frequency measurement and quantum control under decoherence.

  11. Polymers preparation under methane plasma environment

    International Nuclear Information System (INIS)

    Yang Wubao; Cai Zeyong; Zhao Zhen; Qi Lu


    Polymers are prepared under methane plasma environment, and appear to be white, slightly yellow, soft thread-like powders and floc under optical microscope. The polymers contain --CH 3 , -CH 2 , C-O, -C=C-,-OH etc. functional groups, but no simplex carbons. It is found that the solubility of this polymer is less than 0.1mg·ml -1 in different organic solvent. The productivity of the polymers is higher under a plasma environment with higher ionization, higher polarization of neutral gas, lower environment temperature and less permittivity. (authors)

  12. The German Physical Society Under National Socialism (United States)

    Hoffmann, Dieter; Walker, Mark


    The history of the German Physical Society from 1933 to 1945 is not the same as a comprehensive history of physics under Adolf Hitler, but it does reflect important aspects of physicists' work and life during the Third Reich.

  13. Bottom Scour Observed Under Hurricane Ivan

    National Research Council Canada - National Science Library

    Teague, William J; Jarosz, Eva; Keen, Timothy R; Wang, David W; Hulbert, Mark S


    Observations that extensive bottom scour along the outer continental shelf under Hurricane Ivan resulted in the displacement of more than 100 million cubic meters of sediment from a 35x15 km region...

  14. Nuclides migration tests under deep geological conditions

    International Nuclear Information System (INIS)

    Kumata, M.; Vandergraaf, T.T.


    Migration behaviour of technetium and iodine under deep geological conditions was investigated by performing column tests under in-situ conditions at the 240 m level of the Underground Research Laboratory (URL) constructed in a granitic batholith near Pinawa, Manitoba, Canada. 131 I was injected with tritiated water into the column. Tritium and 131 I were eluted simultaneously. Almost 100 % of injected 131 I was recovered in the tritium breakthrough region, indicating that iodine moved through the column almost without retardation under experimental conditions. On the other hand, the injected technetium with tritium was strongly retarded in the column even though the groundwater was mildly reducing. Only about 7 % of injected 95m Tc was recovered in the tritium breakthrough region and the remaining fraction was strongly sorbed on the dark mafic minerals of column materials. This strong sorption of technetium on the column materials had not been expected from the results obtained from batch experiments carried out under anaerobic conditions. (author)

  15. Long term monitoring of moisture under pavements. (United States)


    Monitoring of the environmental instrumentation installed under select pavement sections constructed : by the Ohio Department of Transportation (ODOT) in 1995 on US 23 in Delaware County, Ohio was : continued. The measurements made consisted of soil ...

  16. ROV dives under Great Lakes ice (United States)

    Bolsenga, S.J.; Gannon, John E.; Kennedy, Gregory; Norton, D.C.; Herdendorf, Charles E.


    Observations of the underside of ice have a wide variety of applications. Severe under-ice roughness can affect ice movements, rough under-ice surfaces can scour the bottom disturbing biota and man-made structures such as pipelines, and the flow rate of rivers is often affected by under-ice roughness. A few reported observations of the underside of an ice cover have been made, usually by cutting a large block of ice and overturning it, by extensive boring, or by remote sensing. Such operations are extremely labor-intensive and, in some cases, prone to inaccuracies. Remotely operated vehicles (ROV) can partially solve these problems. In this note, we describe the use, performance in a hostile environment, and results of a study in which a ROV was deployed under the ice in Lake Erie (North American Great Lakes).

  17. CDC WONDER: Mortality - Underlying Cause of Death (United States)

    U.S. Department of Health & Human Services — The CDC WONDER Mortality - Underlying Cause of Death online database is a county-level national mortality and population database spanning the years since 1979. Data...

  18. Nitrous Oxide flux measurements under various amendments (United States)

    U.S. Environmental Protection Agency — The dataset consists of measurements of soil nitrous oxide emissions from soils under three different amendments: glucose, cellulose, and manure. Data includes the...

  19. Driving under the influence of cannabis. (United States)


    As more states decriminalize and legalize medical and recreational use of cannabis (marijuana), traffic safety leaders and public health advocates have growing concerns about driving under the influence of cannabis (DUIC). How do we understand the cu...

  20. Object Construction Under Diverse Conditions of Rearing (United States)

    Hunt, J. McVicker


    This study examines object construction and the ages at which children developing under various environmental conditions achieve five of the landmarks in the Uzgiris-Hunt (1974) scale of object permanence. (Author)

  1. Transformation kinetics of mixed polymeric substrates under ...

    African Journals Online (AJOL)

    bglucosidase and a-mannosidase were abundantly secreted in the growth medium. This research is the first report on mixed polymeric substrate biodegradation under sewer condition by A. niger, and could be considered as an open window on ...

  2. Fiscal Policy under Indeterminacy and Tax Evasion

    DEFF Research Database (Denmark)

    Busato, Francesco; Chiarini, Bruno; Marchetti, Enrico

    This paper shows under indeterminacy and tax evasion, an increase in corporate,labor or income tax rates pushes the economy into an expansionary pattern.These effects are reversed when the steady state is saddle-path stable.......This paper shows under indeterminacy and tax evasion, an increase in corporate,labor or income tax rates pushes the economy into an expansionary pattern.These effects are reversed when the steady state is saddle-path stable....

  3. Robust Satellite Communications Under Hostile Interference (United States)


    or elimination of required feedback signals, jammer herding, multi-source signalling, and interference alignment . In the case of the replace with...AFRL-RV-PS- AFRL-RV-PS- TR-2016-0079 TR-2016-0079 ROBUST SATELLITE COMMUNICATIONS UNDER HOSTILE INTERFERENCE Marc Lichtman and Jeffrey Reed...FA9453-14-1-0222 Robust Satellite Communications Under Hostile Interference 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62601F 6. AUTHOR(S) 5d

  4. Analysis of ship deformation under sailing


    Xiuwen, Shan; Lixiang, Sun; Yi, Pu; Chuncheng, Xu


    With the help of the three-dimensional potential flow theory and the hydrodynamic analysis of the loaded ship, the wave pressure distribution and the design wave parameters of the ship under loading conditions have been analyzed. Using the method of AQWA and ANSYS co-simulation, the stress level, stress distribution and deformation of the whole ship under loading conditions are obtained. The numerical analysis results can provide an effective basis for the assessment of ship navigation safety.

  5. Entry and exit decisions under uncertainty

    DEFF Research Database (Denmark)

    Kongsted, Hans Christian


    This paper establishes the general deterministic limit that corresponds to Dixit's model of entry and exit decisions under uncertainty. The interlinked nature of decisions is shown to be essential also in the deterministic limit. A numerical example illustrates the result......This paper establishes the general deterministic limit that corresponds to Dixit's model of entry and exit decisions under uncertainty. The interlinked nature of decisions is shown to be essential also in the deterministic limit. A numerical example illustrates the result...

  6. Portfolio Selection with Jumps under Regime Switching

    Directory of Open Access Journals (Sweden)

    Lin Zhao


    Full Text Available We investigate a continuous-time version of the mean-variance portfolio selection model with jumps under regime switching. The portfolio selection is proposed and analyzed for a market consisting of one bank account and multiple stocks. The random regime switching is assumed to be independent of the underlying Brownian motion and jump processes. A Markov chain modulated diffusion formulation is employed to model the problem.

  7. Leximin rules for bankruptcy problems under uncertainty (United States)

    Hinojosa, M. A.; Mármol, A. M.; Sánchez, F. J.


    We model bankruptcy problems under uncertainty under the assumption that there are several possible states of nature, each of which is identified with a different bankruptcy problem. For this multi-dimensional extension of classic bankruptcy problems, we consider situations in which agents exhibit at the same time additive preferences and leximin preferences on their possible results. We propose division rules which combine different rationality principles and guarantee efficiency with respect to leximin preferences.

  8. Twist buckling of veins under torsional loading. (United States)

    Garcia, Justin R; Sanyal, Arnav; Fatemifar, Fatemeh; Mottahedi, Mohammad; Han, Hai-Chao


    Veins are often subjected to torsion and twisted veins can hinder and disrupt normal blood flow but their mechanical behavior under torsion is poorly understood. The objective of this study was to investigate the twist deformation and buckling behavior of veins under torsion. Twist buckling tests were performed on porcine internal jugular veins (IJVs) and human great saphenous veins (GSVs) at various axial stretch ratio and lumen pressure conditions to determine their critical buckling torques and critical buckling twist angles. The mechanical behavior under torsion was characterized using a two-fiber strain energy density function and the buckling behavior was then simulated using finite element analysis. Our results demonstrated that twist buckling occurred in all veins under excessive torque characterized by a sudden kink formation. The critical buckling torque increased significantly with increasing lumen pressure for both porcine IJV and human GSV. But lumen pressure and axial stretch had little effect on the critical twist angle. The human GSVs are stiffer than the porcine IJVs. Finite element simulations captured the buckling behavior for individual veins under simultaneous extension, inflation, and torsion with strong correlation between predicted critical buckling torques and experimental data (R 2 =0.96). We conclude that veins can buckle under torsion loading and the lumen pressure significantly affects the critical buckling torque. These results improve our understanding of vein twist behavior and help identify key factors associated in the formation of twisted veins. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. A Spaceborne Multi-Arm Interferometer for VLF Gravitational Wave Detection (the Smile Project) (United States)

    Anderson, A. J.

    This project would be the next step in our ability to detect very low frequency (VLF) gravitational waves and the first committed spaceborn designed experiment. Present Deep Space spacecraft tracking experiments are severely limited in their detection capability. It is proposed to construct a space-borne multi-arm microwave interferometer using current elements of design applicable for the detection of VLF gravitational waves. The elements are outlined with particular emphasis placed on the utilization of small inexpensive get away special modules currently under development at JPL for launch in the 1990's.

  10. Stochastic memory: Memory enhancement due to noise (United States)

    Stotland, Alexander; di Ventra, Massimiliano


    There are certain classes of resistors, capacitors, and inductors that, when subject to a periodic input of appropriate frequency, develop hysteresis loops in their characteristic response. Here we show that the hysteresis of such memory elements can also be induced by white noise of appropriate intensity even at very low frequencies of the external driving field. We illustrate this phenomenon using a physical model of memory resistor realized by TiO2 thin films sandwiched between metallic electrodes and discuss under which conditions this effect can be observed experimentally. We also discuss its implications on existing memory systems described in the literature and the role of colored noise.

  11. Characteristics of Braced Excavation under Asymmetrical Loads

    Directory of Open Access Journals (Sweden)

    Changjie Xu


    Full Text Available Numerous excavation practices have shown that large discrepancies exist between field monitoring data and calculated results when the conventional symmetry-plane method (with half-width is used to design the retaining structure under asymmetrical loads. To examine the characteristics of a retaining structure under asymmetrical loads, we use the finite element method (FEM to simulate the excavation process under four different groups of asymmetrical loads and create an integrated model to tackle this problem. The effects of strut stiffness and wall length are also investigated. The results of numerical analysis clearly imply that the deformation and bending moment of diaphragm walls are distinct on different sides, indicating the need for different rebar arrangements when the excavation is subjected to asymmetrical loads. This study provides a practical approach to designing excavations under asymmetrical loads. We analyze and compare the monitoring and calculation data at different excavation stages and find some general trends. Several guidelines on excavation design under asymmetrical loads are drawn.

  12. Riboflavin ameliorates cisplatin induced toxicities under photoillumination.

    Directory of Open Access Journals (Sweden)

    Iftekhar Hassan

    Full Text Available BACKGROUND: Cisplatin is an effective anticancer drug that elicits many side effects mainly due to induction of oxidative and nitrosative stresses during prolonged chemotherapy. The severity of these side effects consequently restricts its clinical use under long term treatment. Riboflavin is an essential vitamin used in various metabolic redox reactions in the form of flavin adenine dinucleotide and flavin mononucleotide. Besides, it has excellent photosensitizing property that can be used to ameliorate these toxicities in mice under photodynamic therapy. METHODS AND FINDINGS: Riboflavin, cisplatin and their combinations were given to the separate groups of mice under photoilluminated condition under specific treatment regime. Their kidney and liver were excised for comet assay and histopathological studies. Furthermore, Fourier Transform Infrared Spectroscopy of riboflavin-cisplatin combination in vitro was also conducted to investigate any possible interaction between the two compounds. Their comet assay and histopathological examination revealed that riboflavin in combination with cisplatin was able to protect the tissues from cisplatin induced toxicities and damages. Moreover, Fourier Transform Infrared Spectroscopy analysis of the combination indicated a strong molecular interaction among their constituent groups that may be assigned for the protective effect of the combination in the treated animals. CONCLUSION: Inclusion of riboflavin diminishes cisplatin induced toxicities which may possibly make the cisplatin-riboflavin combination, an effective treatment strategy under chemoradiotherapy in pronouncing its antineoplastic activity and sensitivity towards the cancer cells as compared to cisplatin alone.

  13. Flow inside an eye under vitreous surgery (United States)

    Kono, Daiki; Sakamoto, Shun; Sakakibara, Jun


    Vitreous is a clear gel filling the space between crystalline lens and retina in human eye. Under circumstances where the vitreous becomes opaque due to bleeding or other disease, ophthalmologist removes the vitreous from eye by cutting and sucking through a pipe named vitreous cutter, and meanwhile replaces fluid in the eye with a balanced salt solution by injecting it through the infusion port. Jet flow from the infusion port may cause intense flow. Consequently, this may generate a pressure and a shear stress on the retinal wall and possibly lead to the damage of retinal cell. In this study, we visualized the flow inside eye and estimated the shear stress on the retinal wall under the vitreous surgery. Instead of using human eye, we used a spherical shell model simulating human eyeball, and measured the two dimensional distribution of two-component velocity by PIV. Under the condition of Re=66 to 99, which meet in the actual operation, the maximum shear stress reaches 0.4 Pa. This value is insufficient to cause retinal detachment, while any physiological effect on the retinal endothelial cells is still unclear. Flow field under higher Re will be presented in the talk. Supported by Grants-in-Aid for Scientific Research of Japan Society for the Promotion of Science under Grant No. 25289026.

  14. The Prototypical Majority Effect Under Social Influence. (United States)

    Koriat, Asher; Adiv-Mashinsky, Shiri; Undorf, Monika; Schwarz, Norbert


    Majority views are reported with greater confidence and fluency than minority views, with the difference increasing with majority size. This Prototypical Majority Effect (PME) was attributed generally to conformity pressure, but Koriat et al. showed that it can arise from the processes underlying decision and confidence independent of social influence. Here we examined the PME under conditions that differ in social influence. In Experiment 1, a robust PME emerged in the absence of information about the majority views, but the provision sof that information increased the choice of the majority view and magnified the PME. In Experiment 2, a PME emerged in a minority-biased condition that misled participants to believe that the majority view was the minority view, but the PME was stronger in a majority-biased condition. The results were discussed in terms of a dual-process view: The PME observed under social influence may contain externally driven and internally driven components.

  15. Stochastic Dominance under the Nonlinear Expected Utilities

    Directory of Open Access Journals (Sweden)

    Xinling Xiao


    Full Text Available In 1947, von Neumann and Morgenstern introduced the well-known expected utility and the related axiomatic system (see von Neumann and Morgenstern (1953. It is widely used in economics, for example, financial economics. But the well-known Allais paradox (see Allais (1979 shows that the linear expected utility has some limitations sometimes. Because of this, Peng proposed a concept of nonlinear expected utility (see Peng (2005. In this paper we propose a concept of stochastic dominance under the nonlinear expected utilities. We give sufficient conditions on which a random choice X stochastically dominates a random choice Y under the nonlinear expected utilities. We also provide sufficient conditions on which a random choice X strictly stochastically dominates a random choice Y under the sublinear expected utilities.

  16. Stability of gradient semigroups under perturbations (United States)

    Aragão-Costa, E. R.; Caraballo, T.; Carvalho, A. N.; Langa, J. A.


    In this paper we prove that gradient-like semigroups (in the sense of Carvalho and Langa (2009 J. Diff. Eqns 246 2646-68)) are gradient semigroups (possess a Lyapunov function). This is primarily done to provide conditions under which gradient semigroups, in a general metric space, are stable under perturbation exploiting the known fact (see Carvalho and Langa (2009 J. Diff. Eqns 246 2646-68)) that gradient-like semigroups are stable under perturbation. The results presented here were motivated by the work carried out in Conley (1978 Isolated Invariant Sets and the Morse Index (CBMS Regional Conference Series in Mathematics vol 38) (RI: American Mathematical Society Providence)) for groups in compact metric spaces (see also Rybakowski (1987 The Homotopy Index and Partial Differential Equations (Universitext) (Berlin: Springer)) for the Morse decomposition of an invariant set for a semigroup on a compact metric space).

  17. Modelling of diurnal cycle under climate change

    Energy Technology Data Exchange (ETDEWEB)

    Eliseev, A.V.; Bezmenov, K.V.; Demchenko, P.F.; Mokhov, I.I.; Petoukhov, V.K. [Russian Academy of Sciences, Moscow (Russian Federation). Inst. of Atmospheric Physics


    The observed diurnal temperature range (DTR) displays remarkable change during last 30 years. Land air DTR generally decreases under global climate warming due to more significant night minimum temperature increase in comparison with day maximum temperature increase. Atmosphere hydrological cycle characteristics change under global warming and possible background aerosol atmosphere content change may cause essential errors in the estimation of DTR tendencies of change under global warming. The result of this study is the investigation of cloudiness effect on the DTR and blackbody radiative emissivity diurnal range. It is shown that in some cases (particularly in cold seasons) it results in opposite change in DTR and BD at doubled CO{sub 2} atmosphere content. The influence of background aerosol is the same as the cloudiness one

  18. DNA under Force: Mechanics, Electrostatics, and Hydration

    Directory of Open Access Journals (Sweden)

    Jingqiang Li


    Full Text Available Quantifying the basic intra- and inter-molecular forces of DNA has helped us to better understand and further predict the behavior of DNA. Single molecule technique elucidates the mechanics of DNA under applied external forces, sometimes under extreme forces. On the other hand, ensemble studies of DNA molecular force allow us to extend our understanding of DNA molecules under other forces such as electrostatic and hydration forces. Using a variety of techniques, we can have a comprehensive understanding of DNA molecular forces, which is crucial in unraveling the complex DNA functions in living cells as well as in designing a system that utilizes the unique properties of DNA in nanotechnology.

  19. Lossy Channel Games under Incomplete Information

    Directory of Open Access Journals (Sweden)

    Rayna Dimitrova


    Full Text Available In this paper we investigate lossy channel games under incomplete information, where two players operate on a finite set of unbounded FIFO channels and one player, representing a system component under consideration operates under incomplete information, while the other player, representing the component's environment is allowed to lose messages from the channels. We argue that these games are a suitable model for synthesis of communication protocols where processes communicate over unreliable channels. We show that in the case of finite message alphabets, games with safety and reachability winning conditions are decidable and finite-state observation-based strategies for the component can be effectively computed. Undecidability for (weak parity objectives follows from the undecidability of (weak parity perfect information games where only one player can lose messages.

  20. Under-reported income of Russian households

    Directory of Open Access Journals (Sweden)

    Yaroslav Murashov


    Full Text Available In the proposed paper, an attempt is made to estimate the proportion of unstated income for Russian households based on micro data. An overview of microeconomic approaches to estimating the scale of under-reported income is provided. These approaches are weakly represented in the national literature, so their strengths and weaknesses are also analyzed. A theoretical model of household consumer behavior is described that allows the size of under-reported income to be estimated. The structure of household incomes and expenditures is studied based on an RLMS sample for 2012. The model is estimated using household subsamples based on the type of household and household income. The estimation technique utilizes regression variables and random effects. The resulting subsample estimates were applied to the general population and compared with those obtained by other researchers using alternative methods and other data. A comparison is made to estimates of under-reported income developed for British households.

  1. CANDU fuel behaviour under LOCA conditions

    International Nuclear Information System (INIS)

    Kohn, E.


    This report summarizes the current understanding of CANDU fuel-element behaviour under loss-of-coolant (LOCA) accidents. It focuses on a key in-reactor verification experiment conducted at Idaho National Engineering Laboratory (INEL) and on three Canadian in-reactor tests. The in-reactor data, and the considerable body of supporting information developed from out-reactor tests, support the general conclusion that CANDU fuel behaviour during LOCA transients is well understood. Four elements of 37-element CANDU fuel-bundle design were tested under conditions typical of a large-break LOCA blowdown in a CANDU reactor. The purpose of the test was to confirm our current understanding of fuel behaviour under loss-of-coolant accident blowdown conditions. The test also provided data for comparison with predictions made with the steady-state and transient fuel-element performance codes ELESIM and ELOCA. Key components of typical LOCA transients were incorporated in the test: namely, a rapid depressurization rate of the hot coolant, a simultaneous power increase before decreasing to decay values (a power pulse), and prototype fuel element under pre-transient power and burnup conditions. The test was successfully completed in the Power Burst Facility (PBF) reactor at INEL under contract to Ontario Hydro and AECL. The three CANDU Owners Group LOCA tests performed at Chalk River Nuclear Laboratories measured both the thermal-mechanical response and fission-gas release resulting from exposure to a LOCA transient. Results from these three tests provided further confirmation that the behaviour of the fuel under LOCA conditions is understood

  2. Performance of the MAGIC telescopes under moonlight (United States)

    Ahnen, M. L.; Ansoldi, S.; Antonelli, L. A.; Arcaro, C.; Babić, A.; Banerjee, B.; Bangale, P.; Barres de Almeida, U.; Barrio, J. A.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Berti, A.; Bhattacharyya, W.; Biasuzzi, B.; Biland, A.; Blanch, O.; Bonnefoy, S.; Bonnoli, G.; Carosi, R.; Carosi, A.; Chatterjee, A.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Covino, S.; Cumani, P.; Da Vela, P.; Dazzi, F.; De Angelis, A.; De Lotto, B.; de Oña Wilhelmi, E.; Di Pierro, F.; Doert, M.; Domínguez, A.; Dominis Prester, D.; Dorner, D.; Doro, M.; Einecke, S.; Eisenacher Glawion, D.; Elsaesser, D.; Engelkemeier, M.; Fallah Ramazani, V.; Fernández-Barral, A.; Fidalgo, D.; Fonseca, M. V.; Font, L.; Fruck, C.; Galindo, D.; García López, R. J.; Garczarczyk, M.; Gaug, M.; Giammaria, P.; Godinović, N.; Gora, D.; Griffiths, S.; Guberman, D.; Hadasch, D.; Hahn, A.; Hassan, T.; Hayashida, M.; Herrera, J.; Hose, J.; Hrupec, D.; Hughes, G.; Ishio, K.; Konno, Y.; Kubo, H.; Kushida, J.; Kuveždić, D.; Lelas, D.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; Maggio, C.; Majumdar, P.; Makariev, M.; Maneva, G.; Manganaro, M.; Mannheim, K.; Maraschi, L.; Mariotti, M.; Martínez, M.; Mazin, D.; Menzel, U.; Minev, M.; Mirzoyan, R.; Moralejo, A.; Moreno, V.; Moretti, E.; Neustroev, V.; Niedzwiecki, A.; Nievas Rosillo, M.; Nilsson, K.; Ninci, D.; Nishijima, K.; Noda, K.; Nogués, L.; Paiano, S.; Palacio, J.; Paneque, D.; Paoletti, R.; Paredes, J. M.; Paredes-Fortuny, X.; Pedaletti, G.; Peresano, M.; Perri, L.; Persic, M.; Prada Moroni, P. G.; Prandini, E.; Puljak, I.; Garcia, J. R.; Reichardt, I.; Rhode, W.; Ribó, M.; Rico, J.; Rugliancich, A.; Saito, T.; Satalecka, K.; Schroeder, S.; Schweizer, T.; Sillanpää, A.; Sitarek, J.; Šnidarić, I.; Sobczynska, D.; Stamerra, A.; Strzys, M.; Surić, T.; Takalo, L.; Tavecchio, F.; Temnikov, P.; Terzić, T.; Tescaro, D.; Teshima, M.; Torres, D. F.; Torres-Albà, N.; Treves, A.; Vanzo, G.; Vazquez Acosta, M.; Vovk, I.; Ward, J. E.; Will, M.; Zarić, D.


    MAGIC, a system of two imaging atmospheric Cherenkov telescopes, achieves its best performance under dark conditions, i.e. in absence of moonlight or twilight. Since operating the telescopes only during dark time would severely limit the duty cycle, observations are also performed when the Moon is present in the sky. Here we develop a dedicated Moon-adapted analysis to characterize the performance of MAGIC under moonlight. We evaluate energy threshold, angular resolution and sensitivity of MAGIC under different background light levels, based on Crab Nebula observations and tuned Monte Carlo simulations. This study includes observations taken under non-standard hardware configurations, such as reducing the camera photomultiplier tubes gain by a factor ∼1.7 (reduced HV settings) with respect to standard settings (nominal HV) or using UV-pass filters to strongly reduce the amount of moonlight reaching the cameras of the telescopes. The Crab Nebula spectrum is correctly reconstructed in all the studied illumination levels, that reach up to 30 times brighter than under dark conditions. The main effect of moonlight is an increase in the analysis energy threshold and in the systematic uncertainties on the flux normalization. The sensitivity degradation is constrained to be below 10%, within 15-30% and between 60 and 80% for nominal HV, reduced HV and UV-pass filter observations, respectively. No worsening of the angular resolution was found. Thanks to observations during moonlight, the maximal duty cycle of MAGIC can be increased from ∼18%, under dark nights only, to up to ∼40% in total with only moderate performance degradation.

  3. Unsuspected pyocyanin effect in yeast under anaerobiosis. (United States)

    Barakat, Rana; Goubet, Isabelle; Manon, Stephen; Berges, Thierry; Rosenfeld, Eric


    The blue-green phenazine, Pyocyanin (PYO), is a well-known virulence factor produced by Pseudomonas aeruginosa, notably during cystic fibrosis lung infections. It is toxic to both eukaryotic and bacterial cells and several mechanisms, including the induction of oxidative stress, have been postulated. However, the mechanism of PYO toxicity under the physiological conditions of oxygen limitation that are encountered by P. aeruginosa and by target organisms in vivo remains unclear. In this study, wild-type and mutant strains of the yeast Saccharomyces cerevisiae were used as an effective eukaryotic model to determine the toxicity of PYO (100-500 μmol/L) under key growth conditions. Under respiro-fermentative conditions (with glucose as substrate), WT strains and certain H2 O2 -hypersensitive strains showed a low-toxic response to PYO. Under respiratory conditions (with glycerol as substrate) all the strains tested were significantly more sensitive to PYO. Four antioxidants were tested but only N-acetylcysteine was capable of partially counteracting PYO toxicity. PYO did not appear to affect short-term respiratory O2 uptake, but it did seem to interfere with cyanide-poisoned mitochondria through a complex III-dependent mechanism. Therefore, a combination of oxidative stress and respiration disturbance could partly explain aerobic PYO toxicity. Surprisingly, the toxic effects of PYO were more significant under anaerobic conditions. More pronounced effects were observed in several strains including a 'petite' strain lacking mitochondrial DNA, strains with increased or decreased levels of ABC transporters, and strains deficient in DNA damage repair. Therefore, even though PYO is toxic for actively respiring cells, O2 may indirectly protect the cells from the higher anaerobic-linked toxicity of PYO. The increased sensitivity to PYO under anaerobic conditions is not unique to S. cerevisiae and was also observed in another yeast, Candida albicans. © 2013 The Authors

  4. UKAEA underlying research programme annual report

    International Nuclear Information System (INIS)

    Mason, J.P.


    Work from all technical areas of the Authority's underlying research programme is described. This is typically in the form of an interim progress report for the year April 1987 to March 1988. The seventeen chapters report research into radiation damage, fracture studies, chemical effects at surfaces, surface physics and corrosion, fluid mechanics and heat transfer, nuclear studies, neutron beam studies, theoretical sciences, instrumentation, reactor physics and control, fabrication processes, laser isotope separation, nuclear fuel cycle studies, quantum electronics, radiological protection, and miscellaneous underlying research. (author)

  5. Wind turbine blade testing under combined loading

    DEFF Research Database (Denmark)

    Roczek-Sieradzan, Agnieszka; Nielsen, Magda; Branner, Kim


    The paper presents full-scale blade tests under a combined flap- and edgewise loading. The main aim of this paper is to present the results from testing a wind turbine blade under such conditions and to study the structural behavior of the blade subjected to combined loading. A loading method using...... anchor plates was applied, allowing transverse shear distortion. The global and local deformation of the blade as well as the reproducibility of the test was studied and the results from the investigations are presented....

  6. Underlying Event Studies for LHC Energies

    International Nuclear Information System (INIS)

    Barnafoeldi, Gergely Gabor; Levai, Peter; Agocs, Andras G.


    Underlying event was originally defined by the CDF collaboration decades ago. Here we improve the original definition to extend our analysis for events with multiple-jets. We introduce a definition for surrounding rings/belts and based on this definition the jet- and surrounding-belt-excluded areas will provide a good underlying event definition. We inverstigate our definition via the multiplicity in the defined geometry. In parallel, mean transverse momenta of these areas also studied in proton-proton collisions at √(s) = 7 TeV LHC energy.

  7. Mining under kalina and Selisoo Bogs


    Otsmaa, Merle


    Continuous developing of Estonian power engineering on the basis of oil shale requires ever taking into use of new exploration fields. When the reserve of Estonia mine is depleted, mining of the exploration field of Seli has to be started. But that field is located under the Selisoo bog which is defined as a region of the Natura 2000 network and is planned become a nature preserve. Conservationists are interested for what extent oil shale mining under the Selisoo bog and in its immediate near...

  8. Vision under mesopic and scotopic illumination

    Directory of Open Access Journals (Sweden)

    Andrew J Zele


    Full Text Available Evidence has accumulated that rod activation under mesopic and scotopic light levels alters visual perception and performance. Here we review the most recent developments in the measurement of rod and cone contributions to mesopic color perception and temporal processing, with a focus on data measured using the four-primary photostimulator method that independently controls rod and cone excitations. We discuss the findings in the context of rod inputs to the three primary retinogeniculate pathways to understand rod contributions to mesopic vision. Additionally, we present evidence that hue perception is possible under scotopic, pure rod-mediated conditions that involves cortical mechanisms.

  9. Thermodynamical instabilities under strong magnetic fields (United States)

    Chen, Y. J.


    The thermodynamical instabilities of low densities in the n p matter and n p e matter are studied within several relativistic nuclear models under some values of magnetic fields. The results are compared between each other and the effects of the symmetry energy slope at saturation density on the instability are investigated. The instability regions can exhibit bands due to the presence of Landau levels for very strong magnetic fields of the order of 1017 G, while for weaker magnetic fields, the bands are replaced by many diffused or scattered pieces. It also shows that the proton fraction in the inner crust of neutron stars may be complex under strong magnetic fields.

  10. Radionuclide Transport Models Under Ambient Conditions

    Energy Technology Data Exchange (ETDEWEB)

    G. Moridis; Q. Hu


    The purpose of Revision 00 of this Analysis/Model Report (AMR) is to evaluate (by means of 2-D semianalytical and 3-D numerical models) the transport of radioactive solutes and colloids in the unsaturated zone (UZ) under ambient conditions from the potential repository horizon to the water table at Yucca Mountain (YM), Nevada.

  11. Comparison of clinical hematological changes under ...

    African Journals Online (AJOL)

    The objectives of this study were to compare the clinical hematological changes under anesthetization in Crucian carp (Carassius auratus auratus) due to treatment with local anesthetics. Our data indicate that the values declined significantly (P < 0.05) with dissolved oxygen amount after anesthetization, furthermore, the ...

  12. Testing boron carbide under triaxial compression (United States)

    Anderson, Charles; Chocron, Sidney; Dannemann, Kathryn A.; Nicholls, Arthur E.


    This article focuses on the pressure dependence and summarizes the characterization work conducted on intact and predamaged specimens of boron carbide under confinement in a pressure vessel and in a thick steel sleeve. The failure curves obtained are presented, and the data compared to experimental data from the literature.

  13. Robust Utility Maximization Under Convex Portfolio Constraints

    International Nuclear Information System (INIS)

    Matoussi, Anis; Mezghani, Hanen; Mnif, Mohamed


    We study a robust maximization problem from terminal wealth and consumption under a convex constraints on the portfolio. We state the existence and the uniqueness of the consumption–investment strategy by studying the associated quadratic backward stochastic differential equation. We characterize the optimal control by using the duality method and deriving a dynamic maximum principle

  14. Optimal portfolio choice under loss aversion

    NARCIS (Netherlands)

    A.B. Berkelaar (Arjan); R.R.P. Kouwenberg (Roy)


    textabstractProspect theory and loss aversion play a dominant role in behavioral finance. In this paper we derive closed-form solutions for optimal portfolio choice under loss aversion. When confronted with gains a loss averse investor behaves similar to a portfolio insurer. When confronted with

  15. Robust Utility Maximization Under Convex Portfolio Constraints

    Energy Technology Data Exchange (ETDEWEB)

    Matoussi, Anis, E-mail: [Université du Maine, Risk and Insurance institut of Le Mans Laboratoire Manceau de Mathématiques (France); Mezghani, Hanen, E-mail:; Mnif, Mohamed, E-mail: [University of Tunis El Manar, Laboratoire de Modélisation Mathématique et Numérique dans les Sciences de l’Ingénieur, ENIT (Tunisia)


    We study a robust maximization problem from terminal wealth and consumption under a convex constraints on the portfolio. We state the existence and the uniqueness of the consumption–investment strategy by studying the associated quadratic backward stochastic differential equation. We characterize the optimal control by using the duality method and deriving a dynamic maximum principle.

  16. Organizational Learning in Schools under Sanction

    Directory of Open Access Journals (Sweden)

    Kara S. Finnigan


    Full Text Available The focus on “school turnaround” has become central to policy and practice in the United States as a result of school accountability, yet little remains known about school improvement under sanction. This study uses theories of organizational learning to understand the processes through which educators search for and adopt reform strategies, as well as the extent to which these schools’ organizational culture and climate are conducive to this type of learning. Our mixed methods study involves document analysis, intensive case studies, and a survey of teachers in schools under sanction in a large urban school district in the USA. We found limited evidence of organizational learning, and instead evidence suggested superficial use of restructuring planning, rare diagnoses of root causes of low performance, and limited engagement in learning processes of school staff. In addition, schools relied on exploitation resulting in the recycling of previous practices. In part, the limited organizational learning in evidence was the result of structures and climates within these low-performing schools that inhibited a more learning-oriented approach to reform. Our study has implications for school improvement under accountability policies as it uncovers important challenges that limit organizational learning and, as a result, school improvement under sanction.

  17. Coping under pressure: Strategies for maintaining confidence ...

    African Journals Online (AJOL)


    Aug 11, 2010 ... Coping under pressure: Strategies for maintaining confidence amongst South African soccer coaches. Authors: Jhalukpreya Surujlal1. Sheila Nguyen2. Affiliations: 1Faculty of Management. Sciences, Vaal University of. Technology, South Africa. 2Faculty of Business and Law, School of. Management and.

  18. Cycling under the influence of alcohol.

    NARCIS (Netherlands)

    Waard, D. de & Houwing, S.


    Accident statistics suggest that alcohol plays an important role in fatal accidents of bicycle riders. However, with which Blood Alcohol Concentration (BAC) cyclists ride their bike is not known. In particular on nights out cycling under influence of alcohol seems common. To evaluate prevalence of


    African Journals Online (AJOL)

    Fr. Ikenga

    Abstract. Over the past few years, the extent to which international law allows States to exercise their jurisdiction in criminal matters has been a subject of diplomatic tensions between States. The purpose of this paper is to shed some light, on the question as to what extent a State, powerful or weak, has a right under.

  20. Timber joints under long-term loading

    DEFF Research Database (Denmark)

    Feldborg, T.; Johansen, M.

    This report describes tests and results from stiffness and strength testing of splice joints under long-term loading. During two years of loading the spicimens were exposed to cyclically changing relative humidity. After the loading period the specimens were short-term tested. The connectors were...

  1. Definition of Terrorist Act under Eth Law

    African Journals Online (AJOL)


    Abstract. While regional and international human rights institutions claim that the definition of a terrorist act under the Anti-terrorism Proclamation No. 652/2009 is overly broad as a result of which citizens not involved in a genuinely terrorist act are prosecuted and jailed, the Ethiopian government defends the law pointing ...

  2. Decision-making under risk and uncertainty

    International Nuclear Information System (INIS)

    Gatev, G.I.


    Fuzzy sets and interval analysis tools to make computations and solve optimisation problems are presented. Fuzzy and interval extensions of Decision Theory criteria for decision-making under parametric uncertainty of prior information (probabilities, payoffs) are developed. An interval probability approach to the mean-value criterion is proposed. (author)

  3. Dexmedetomidine premedication in cataract surgery under topical ...

    African Journals Online (AJOL)

    Keywords: cataract surgery, dexmedetomidine, intraocular pressure, patient and surgeon satisfaction, topical anesthesia. Introduction. Traditionally, cataract surgeries are performed under regional anaesthesia with either a peribulbar or retrobulbar block. With the anaesthesia has also evolved from painful regional blocks to ...

  4. An investigation into the mechanism underlying enhanced ...

    African Journals Online (AJOL)

    The solubilisation of primary sewage sludge under sulphate reducing conditions was conducted in controlled flask studies and previously reported findings of enhanced hydrolysis were confirmed. The maximum percentage solubilisation obtained in this study over a 10-day period was 31% and 64% for the methanogenic ...

  5. Controlled temperature grinding under modified atmosphere for ...

    African Journals Online (AJOL)

    Controlled temperature grinding under modified atmosphere for Almond (Prunus Dulcis) paste production. ... incremental gain of 27% and 21% in the protein and fat content, respectively. Keywords: Almonds; Food Processing Aspects; Lipid Oxidation International Journal of Engineering, Science and Technology, Vol. 2, No.

  6. Stone Stability under Stationary Nonuniform Flows

    NARCIS (Netherlands)

    Steenstra, Remco; Hofland, B.; Paarlberg, Andries; Smale, Alfons; Huthoff, Fredrik; Uijttewaal, W.S.J.


    A stability parameter for rock in bed protections under nonuniform stationary flow is derived. The influence of the mean flow velocity, turbulence, and mean acceleration of the flow are included explicitly in the parameter. The relatively new notion of explicitly incorporating the mean acceleration

  7. Monopod bucket foundations under cyclic lateral loading

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo

    on bucket foundations under lateral cyclic loading. The test setup is described in detail and a comprehensive experimental campaign is presented. The foundation is subjected to cyclic overturning moment, cyclic horizontal loading and constant vertical loading, acting on the same plane for thousands...

  8. The decomposition of estuarine macrophytes under different ...

    African Journals Online (AJOL)

    The low levels of total oxidised nitrogen (nitrate and nitrite) released during decomposition were attributed to the inhibition of nitrification by heterotrophic bacteria under anoxic conditions. The relative levels of dissolved inorganic phosphorus (DIP) released were lower than that observed for DIN, and peaked early on in the ...

  9. Earthworm Cast Biomass Under Three Managed Ecosystems ...

    African Journals Online (AJOL)

    The study was conducted to determine earthworm cast biomass under three managed ecosystems, Gmelina, Cashew and Banana plantations at Federal University of Agriculture, Abeokuta and its impact on the soil physicochemical parameters. Seven, five and four plots of 3 m2 each were sampled in Gmelina, Cashew and ...

  10. Rural areas under urban pressure in Europe

    NARCIS (Netherlands)

    Overbeek, M.M.M.


    In this Introduction paper, I will describe the motivation behind this special issue on the role of rural-urban relationships in preserving the rural landscape in Europe. Based on the RURBAN project 'Building new relationships in rural areas under urban pressure', the special issue aims to identify

  11. Optimal Portfolios Under Dynamic Shortfall Constraints | Akume ...

    African Journals Online (AJOL)

    industry standard with regulatory authorities enforcing its use in risk measurement and management. Despite its widespread acceptance, VaR is not coherent. Tail Conditional Expectation (TCE), on the other hand, for an underlying continuous distribution, is a coherent risk measures. Our focus in this paper is the dynamic ...

  12. anthropometric and biochemical assessment among under five

    African Journals Online (AJOL)

    DR. AMIN

    Micronutrient deficiencies, especially iron and iodine cause delayed psychomotor development and impaired cognitive function (Leo,. 2011). There are many under nourished children in. Katsina State (Doctors without Border, 2009). Consequently, this study was designed to estimate the prevalence of malnutrition among ...

  13. Individual differences in performance under acute stress

    NARCIS (Netherlands)

    Delahaij, R.; Gaillard, A.W.K.


    To be able to predict which persons are capable to perform under acute stress is important for the selection and training of professionals in the military, police, and fire- fighting domain. The present study examines how individual differences in coping (style, efficacy, and behavior) explain

  14. Genes under positive selection in Escherichia coli

    DEFF Research Database (Denmark)

    Petersen, Lise; Bollback, Jonathan P; Dimmic, Matt


    We used a comparative genomics approach to identify genes that are under positive selection in six strains of Escherichia coli and Shigella flexneri, including five strains that are human pathogens. We find that positive selection targets a wide range of different functions in the E. coli genome...

  15. Oil and gas. Gas supply under pressure

    International Nuclear Information System (INIS)

    Forbes, A.


    The latest review of natural gas markets from the International Energy Agency (IEA) paints a picture of growing demand in the face of rising prices, a strengthening link between gas and electricity markets, and a globalising influence from increasingly flexible LNG supplies. But there are growing signs that security of supply is under threat from underinvestment, delays and cost escalation

  16. Hypoxaemia During Gynaecological Laparoscopy Under Local ...

    African Journals Online (AJOL)

    Conclusion: A significant degree of desaturation occurs during gynaecologic laparoscopy under pentazocine and diazepam sedation. It is recommended that oxygen should be administered to all patients during the procedure. Key Words: Gynaecological Laparoscopy, Sedation, Hypoxaemia. [Trop J Obstet Gynaecol, 2002, ...

  17. Decision-making under great uncertainty

    International Nuclear Information System (INIS)

    Hansson, S.O.


    Five types of decision-uncertainty are distinguished: uncertainty of consequences, of values, of demarcation, of reliance, and of co-ordination. Strategies are proposed for each type of uncertainty. The general conclusion is that it is meaningful for decision theory to treat cases with greater uncertainty than the textbook case of 'decision-making under uncertainty'. (au)

  18. Conservation of wave action under multisymplectic discretizations

    NARCIS (Netherlands)

    J.E. Frank (Jason)


    textabstractIn this paper we discuss the conservation of wave action under numerical discretization by variational and multisymplectic methods. Both the general wave action conservation defined with respect to a smooth, periodic, one-parameter ensemble of flow realizations and the specific wave

  19. Biofortified varieties released under HarvestPlus

    African Journals Online (AJOL)

    Chapter 5: Annex 1 - Biofortified varieties released under HarvestPlus (as of December 2016). Crop. Micronutrient. Country. Variety. Year of Release. Origin. Type. Baseline. (ppm). Target increment. (ppm). Increment. (ppm). % Target. Increment. (ppm). Micronutrient. Content. (ppm). 11940. BRRI dhan64. 2014. BRRI. Boro.

  20. Experiments in Decision-Making under Risk

    NARCIS (Netherlands)

    Krawczyk, M.W.


    This thesis presents experimental research on deviations from the standard theory of decision-making under risk. It focuses on two types of situations in which they are likely to occur. In the first part, the case of individual decision making with delayed resolution of risk is considered. It is

  1. Colloidal Aggregate Structure under Shear by USANS (United States)

    Chatterjee, Tirtha; van Dyk, Antony K.; Ginzburg, Valeriy V.; Nakatani, Alan I.


    Paints are complex formulations of polymeric binders, inorganic pigments, dispersants, surfactants, colorants, rheology modifiers, and other additives. A commercially successful paint exhibits a desired viscosity profile over a wide shear rate range from 10-5 s-1 for settling to >104 s-1 for rolling, and spray applications. Understanding paint formulation structure is critical as it governs the paint viscosity profile. However, probing paint formulation structure under shear is a challenging task due to the formulation complexity containing structures with different hierarchical length scales and their alterations under the influence of an external flow field. In this work mesoscale structures of paint formulations under shear are investigated using Ultra Small-Angle Neutron Scattering (rheo-USANS). Contrast match conditions were utilized to independently probe the structure of latex binder particle aggregates and the TiO2 pigment particle aggregates. Rheo-USANS data revealed that the aggregates are fractal in nature and their self-similarity dimensions and correlations lengths depend on the chemistry of the binder particles, the type of rheology modifier present and the shear stress imposed upon the formulation. These results can be explained in the framework of diffusion and reaction limited transient aggregates structure evolution under simple shear.

  2. Legal liability under an IDM program. (United States)

    Wolfe, D L; Stanton, T J


    Integrated disability management (IDM) programs offer employers a simple, strategic approach to managing health and lost time. However, components of these programs also present potential liabilities under federal, and sometimes, state law. This article reviews the sources of these liabilities and summarizes techniques for minimizing the risk of employers (and managers individually).

  3. Deciphering the Cognitive and Neural Mechanisms Underlying ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Deciphering the Cognitive and Neural Mechanisms Underlying Auditory Learning. This project seeks to understand the brain mechanisms necessary for people to learn to perceive sounds. Neural circuits and learning. The research team will test people with and without musical training to evaluate their capacity to learn ...

  4. Density and viscosity of lipids under pressure (United States)

    There is a lack of data for the viscosity of lipids under pressure. The current report is a part of the effort to fill this gap. The viscosity, density, and elastohydrodynamic film thicknesses of vegetable oil (HOSuO) were investigated. Pressure–viscosity coefficients (PVC) of HOSuO at different tem...

  5. Amorphization of ice under mechanical stresses (United States)

    Bordonskii, G. S.; Krylov, S. D.


    The dielectric parameters of freshly produced freshwater ice in the microwave range are investigated. It is established that this kind of ice contains a noticeable amount of amorphous ice. Its production is associated with plastic deformation under mechanical stresses. An assessment of the dielectric-permeability change caused by amorphous ice in the state of a slowly flowing medium is given.

  6. Coupon advertising under imperfect price information

    NARCIS (Netherlands)

    Moraga-Gonzälez, José Luis; Petrakis, Emmanuel


    This paper studies sales promotions through coupons in an oligopoly under imperfect price information. Sellers can distribute either ordinary coupons, or coupon (price) advertising, or both types of coupons, at distant locations to attract consumers from their rivals' markets. A unique symmetric

  7. Health and safety standards under deregulation threat

    NARCIS (Netherlands)

    Cremers, Jan


    In the quarterly CLR-News (2-2015), titled ‘The future of the EU health and safety legislation’ ( under Publications), editor Jan Cremers (Law School UvT and AIAS) questions whether the OHS-policy developed is internal market proof and resistant enough to the reigning dogma of

  8. (Abelmoschus esculentus (L.) Moench) UNDER SALINE STRESS ...

    African Journals Online (AJOL)

    H. Rahim Guealia

    1 sept. 2017 ... treatments of NaCl (Control, 100 mM and 300 mM) for 7 days, on young okra plants. (Abelmoschus esculentus), grown in two types of substrate with bentonite (B) 7% and without bentonite (WB) under controlled greenhouse conditions. The results showed that the two factors (salinity and bentonite) imposed ...

  9. Stress-testing banks under deep uncertainty

    NARCIS (Netherlands)

    Islam, T.; Vasilopoulos, C.; Pruyt, E.


    Years of turmoil in the banking sector have revealed the need to assess bank performance under deep uncertainty and identify vulnerabilities to different types of risks. Banks are not the safe houses of old. Today, banks are highly uncertain dynamically complex systems that are permanently at risk

  10. Structure of polymer chains under confinement

    Indian Academy of Sciences (India)

    cluded volume interactions (so-called regime of “semi-dilute cigars”). For confined charged polymers, a peak is observed whose intensity increases with molecular weight and the asymptotic 1/q scattering region is extended compared to the bulk. We infer that the chains are sufficiently extended, under the influence of ...


    Energy Technology Data Exchange (ETDEWEB)

    S. Magnuson


    The purpose of this model report is to document the unsaturated zone (UZ) radionuclide transport model, which evaluates, by means of three-dimensional numerical models, the transport of radioactive solutes and colloids in the UZ, under ambient conditions, from the repository horizon to the water table at Yucca Mountain, Nevada.

  12. Bayesian estimations in the Kumaraswamy distribution under ...

    African Journals Online (AJOL)

    ... the parameter of the Kumaraswamy distribution, Bayes approach under squared error loss function in the reliability function has been suggested based on the pervious observations, this approach can be used for both progressively type II censorings. The study is useful for researchers and practitioners in reliability theory ...

  13. Characteristics of a Dairy Process under Uncertainty

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan


    In this work, the characteristics of a dairy production process under diverse product uncertainties are investigated through a process simulation. The flexibility analysis method of Grossmann and his co-workers (Swaney and Grossmann, 1985) is applied through a process simulation tool, PRO/II. A new...

  14. Parametric study of radiofrequency helium discharge under ...

    Indian Academy of Sciences (India)

    The parameters of radio frequency helium discharge under atmospheric pressure were studied by electrical and optical measurements using high voltage probe, current probe and optical emission spectroscopy. Two discharge modes α and γ were observed within certain limits. During α to γ mode transition, a decrease in ...

  15. Optimal annuity portfolio under inflation risk

    DEFF Research Database (Denmark)

    Konicz, Agnieszka Karolina; Pisinger, David; Weissensteiner, Alex


    The paper investigates the importance of in ation-linked annuities to individuals facing in ation risk. Given the investment opportunities in nominal, real, and variable annuities, as well as cash and stocks, we investigate the consumption and investment decisions under two different objective fu...

  16. Transient burnout under rapid flow reduction condition

    International Nuclear Information System (INIS)

    Iwamura, Takamichi


    Burnout characteristics were experimentally studied using uniformly heated tube and annular test sections under rapid flow reduction conditions. Observations indicated that the onset of burnout under a flow reduction transient is caused by the dryout of a liquid film on the heated surface. The decrease in burnout mass velocity at the channel inlet with increasing flow reduction rate is attributed to the fact that the vapor flow rate continues to increase and sustain the liquid film flow after the inlet flow rate reaches the steady-state burnout flow rate. This is because the movement of the boiling boundary cannot keep up with the rapid reduction of inlet flow rate. A burnout model for the local condition could be applied to the burnout phenomena with the flow reduction under pressures of 0.5 ∼ 3.9 MPa and flow reduction rates of 0.6 ∼ 35 %/s. Based on this model, a method to predict the burnout time under a flow reduction condition was presented. The calculated burnout times agreed well with experimental results obtained by some investigators. (author)

  17. Radionuclide Transport Models Under Ambient Conditions

    International Nuclear Information System (INIS)

    Moridis, G.; Hu, Q.


    The purpose of Revision 00 of this Analysis/Model Report (AMR) is to evaluate (by means of 2-D semianalytical and 3-D numerical models) the transport of radioactive solutes and colloids in the unsaturated zone (UZ) under ambient conditions from the potential repository horizon to the water table at Yucca Mountain (YM), Nevada

  18. Orientation of migratory birds under ultraviolet light. (United States)

    Wiltschko, Roswitha; Munro, Ursula; Ford, Hugh; Stapput, Katrin; Thalau, Peter; Wiltschko, Wolfgang


    In view of the finding that cryptochrome 1a, the putative receptor molecule for the avian magnetic compass, is restricted to the ultraviolet single cones in European Robins, we studied the orientation behaviour of robins and Australian Silvereyes under monochromatic ultraviolet (UV) light. At low intensity UV light of 0.3 mW/m(2), birds showed normal migratory orientation by their inclination compass, with the directional information originating in radical pair processes in the eye. At 2.8 mW/m(2), robins showed an axial preference in the east-west axis, whereas silvereyes preferred an easterly direction. At 5.7 mW/m(2), robins changed direction to a north-south axis. When UV light was combined with yellow light, robins showed easterly 'fixed direction' responses, which changed to disorientation when their upper beak was locally anaesthetised with xylocaine, indicating that they were controlled by the magnetite-based receptors in the beak. Orientation under UV light thus appears to be similar to that observed under blue, turquoise and green light, albeit the UV responses occur at lower light levels, probably because of the greater light sensitivity of the UV cones. The orientation under UV light and green light suggests that at least at the level of the retina, magnetoreception and vision are largely independent of each other.

  19. Plasticity under rough surface contact and friction

    NARCIS (Netherlands)

    Sun, F.


    The ultimate objective of this work is to gain a better understanding of the plastic behavior of rough metal surfaces under contact loading. Attention in this thesis focuses on the study of single and multiple asperities with micrometer scale dimensions, a scale at which plasticity is known to be

  20. Theory Underlying a National Teacher Evaluation Program (United States)

    Taut, Sandy; Santelices, Veronica; Araya, Carolina; Manzi, Jorge


    The paper describes a study conducted to explicate the multiple theories underlying Chile's national teacher evaluation program. These theories will serve as the basis for evaluating the intended consequences of this evaluation system, while not losing sight of emerging unintended consequences. We first analyzed legal and policy documents and then…

  1. Pests and Agricultural Production under Climate Change


    Ameden, Holly A.; Just, David R.


    Although the effect of climate change on agricultural pests has been studied by biologists, thus far, large-scale assessments of climate change and agriculture have not included the impact of pests. We develop a simple theoretical model of farmer-pest interaction under climate change and explore the potential impacts on land values.

  2. Transformation kinetics of mixed polymeric substrates under ...

    African Journals Online (AJOL)


    The residual biomasses of fungi used in industries to produce enzymes are stocked in landfill nowadays, but they could serve as inoculums for pretreatment. The aims of this study were (i) to determine the kinetics of the pretreatment under transitory conditions of a synthetic wastewater containing a mixture of starch and.

  3. Complex Plasma Research Under Extreme Conditions

    International Nuclear Information System (INIS)

    Ishihara, Osamu


    Complex plasma research under extreme conditions is described. The extreme conditions include low-dimensionality for self-organized structures of dust particles, dust magnetization in high magnetic field, criticality in phase transition, and cryogenic environment for Coulomb crystals and dust dynamics.

  4. Experience Of Thoracic Surgery Performed Under Difficult ...

    African Journals Online (AJOL)

    rely on a standard thoracic set with Finocchietto retractor, lung retractor, rib cutter and Lubsche sternotome. After completing the operation, proper haemostasis was obtained and the pleural cavity was irrigated with warm physiologic solution. Two chest tubes (size 36F and 28F) were applied and connected with "under.

  5. Geographic disparity in kidney transplantation under KAS. (United States)

    Zhou, Sheng; Massie, Allan B; Luo, Xun; Ruck, Jessica M; Chow, Eric K H; Bowring, Mary G; Bae, Sunjae; Segev, Dorry L; Gentry, Sommer E


    The Kidney Allocation System fundamentally altered kidney allocation, causing a substantial increase in regional and national sharing that we hypothesized might impact geographic disparities. We measured geographic disparity in deceased donor kidney transplant (DDKT) rate under KAS (6/1/2015-12/1/2016), and compared that with pre-KAS (6/1/2013-12/3/2014). We modeled DSA-level DDKT rates with multilevel Poisson regression, adjusting for allocation factors under KAS. Using the model we calculated a novel, improved metric of geographic disparity: the median incidence rate ratio (MIRR) of transplant rate, a measure of DSA-level variation that accounts for patient casemix and is robust to outlier values. Under KAS, MIRR was 1.75 1.81 1.86 for adults, meaning that similar candidates across different DSAs have a median 1.81-fold difference in DDKT rate. The impact of geography was greater than the impact of factors emphasized by KAS: having an EPTS score ≤20% was associated with a 1.40-fold increase (IRR =  1.35 1.40 1.45 , P geographic disparities with KAS (P = .3). Despite extensive changes to kidney allocation under KAS, geography remains a primary determinant of access to DDKT. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  6. Genes Underlying Positive Influence Of Prenatal Environmental ...

    African Journals Online (AJOL)

    We aimed to investigate and find out key genes underlying the positive-negative effects derived from prenatal interventions. Materials and Methods: Pregnant rats were randomized into EE group (EEG), earthquake simulation group (ESG), herbal group (HG) received herbal supplements in feed after earthquake simulation, ...

  7. Coverage maximization under resource constraints using ...

    Indian Academy of Sciences (India)


    Feb 7, 2015 ... Dissemination of information has been one of the prime needs in almost every kind of communication network. The existing algorithms for this service, try to maximize the coverage, i.e., the number of distinct nodes to which a given piece of information could be conveyed under the constraints of time and ...

  8. Synchronization analysis of coloured delayed networks under ...

    Indian Academy of Sciences (India)

    This paper investigates synchronization of coloured delayed networks under decentralized pinning intermittent control. To begin with, the time delays are taken into account in the coloured networks. In addition, we propose a decentralized pinning intermittent control for coloured delayed networks, which is different from that ...

  9. Optimal Portfolios Under Dynamic Shortfall Constraints

    African Journals Online (AJOL)

    industry standard with regulatory authorities enforcing its use in risk measure- ment and management. Despite its widespread acceptance, VaR is not coherent. Tail Conditional Expectation (TCE), on the other hand, for an underlying con- tinuous distribution, is a coherent risk measures. Our focus in this paper is the dynamic ...

  10. Single curved fiber sedimentation under gravity (United States)

    Xiaoying Rong; Dewei Qi; Junyong Zhu


    Dynamics of single curved fiber sedimentation under the gravity are simulated by using lattice Boltzmann method. The results of migration and rotation of the curved fiber at different Reynolds numbers are reported. The results show that the rotation and migration processes are sensitive to the curvature of the fiber.


    African Journals Online (AJOL)

    Fr. Ikenga

    Regulations Enforcement Agency (NESREA) (Establishment) Act 2007 and the Harmful Waste (Special Criminal ... agent and the notice shall clearly state the cause of action, particulars of the claim, name and place of ..... under common law, but the plaintiff must show that the defendant was careless in the exercise of a.

  12. Pluralism and Prayer under One Roof. (United States)

    McMurtrie, Beth


    Reports on increasing efforts by colleges and universities to meet the spiritual needs of minority students by providing religious centers where students of all faiths can worship under one roof. Examples include the Massachusetts Institute of Technology, Mount Holyoke College (Massachusetts), and Johns Hopkins University (Maryland). (DB)

  13. Buckwheat stomatal traits under aluminium toxicity

    Directory of Open Access Journals (Sweden)

    Oleksandr E. Smirnov


    Full Text Available Aluminium influence on some stomatal parameters of common buckwheat (Fagopyrum esculentum Moench. was studied. Significant changes in stomatal density, stomatal index and stomatal shape coefficient under aluminium treatment were revealed. Stomatal closure and no difference in total stomatal potential conductance index of treatment plants were suggested as aluminium resistance characteristics.

  14. Olfactory bulb encoding during learning under anaesthesia

    Directory of Open Access Journals (Sweden)

    Alister U Nicol


    Full Text Available Neural plasticity changes within the olfactory bulb are important for olfactory learning, although how neural encoding changes support new associations with specific odours and whether they can be investigated under anaesthesia, remain unclear. Using the social transmission of food preference olfactory learning paradigm in mice in conjunction with in vivo microdialysis sampling we have shown firstly that a learned preference for a scented food odour smelled on the breath of a demonstrator animal occurs under isofluorane anaesthesia. Furthermore, subsequent exposure to this cued odour under anaesthesia promotes the same pattern of increased release of glutamate and GABA in the olfactory bulb as previously found in conscious animals following olfactory learning, and evoked GABA release was positively correlated with the amount of scented food eaten. In a second experiment, multiarray (24 electrodes electrophysiological recordings were made from olfactory bulb mitral cells under isofluorane anaesthesia before, during and after a novel scented food odour was paired with carbon disulfide. Results showed significant increases in overall firing frequency to the cued-odour during and after learning and decreases in response to an uncued odour. Analysis of patterns of changes in individual neurons revealed that a substantial proportion (>50% of them significantly changed their response profiles during and after learning with most of those previously inhibited becoming excited. A large number of cells exhibiting no response to the odours prior to learning were either excited or inhibited afterwards. With the uncued odour many previously responsive cells became unresponsive or inhibited. Learning associated changes only occurred in the posterior part of the olfactory bulb. Thus olfactory learning under anaesthesia promotes extensive, but spatially distinct, changes in mitral cell networks to both cued and uncued odours as well as in evoked glutamate and

  15. Olfactory bulb encoding during learning under anesthesia (United States)

    Nicol, Alister U.; Sanchez-Andrade, Gabriela; Collado, Paloma; Segonds-Pichon, Anne; Kendrick, Keith M.


    Neural plasticity changes within the olfactory bulb are important for olfactory learning, although how neural encoding changes support new associations with specific odors and whether they can be investigated under anesthesia, remain unclear. Using the social transmission of food preference olfactory learning paradigm in mice in conjunction with in vivo microdialysis sampling we have shown firstly that a learned preference for a scented food odor smelled on the breath of a demonstrator animal occurs under isofluorane anesthesia. Furthermore, subsequent exposure to this cued odor under anesthesia promotes the same pattern of increased release of glutamate and gamma-aminobutyric acid (GABA) in the olfactory bulb as previously found in conscious animals following olfactory learning, and evoked GABA release was positively correlated with the amount of scented food eaten. In a second experiment, multiarray (24 electrodes) electrophysiological recordings were made from olfactory bulb mitral cells under isofluorane anesthesia before, during and after a novel scented food odor was paired with carbon disulfide. Results showed significant increases in overall firing frequency to the cued-odor during and after learning and decreases in response to an uncued odor. Analysis of patterns of changes in individual neurons revealed that a substantial proportion (>50%) of them significantly changed their response profiles during and after learning with most of those previously inhibited becoming excited. A large number of cells exhibiting no response to the odors prior to learning were either excited or inhibited afterwards. With the uncued odor many previously responsive cells became unresponsive or inhibited. Learning associated changes only occurred in the posterior part of the olfactory bulb. Thus olfactory learning under anesthesia promotes extensive, but spatially distinct, changes in mitral cell networks to both cued and uncued odors as well as in evoked glutamate and GABA

  16. Decision making under ambiguity but not under risk is related to problem gambling severity

    NARCIS (Netherlands)

    Brevers, Damien; Cleeremans, Axel; Goudriaan, Anna E.; Bechara, Antoine; Kornreich, Charles; Verbanck, Paul; Noël, Xavier


    The aim of the present study was to examine the relationship between problem gambling severity and decision-making situations that vary in two degrees of uncertainty (probability of outcome is known: decision-making under risk; probability of outcome is unknown: decision-making under ambiguity). For

  17. The duties of the seller under the civil code and under the Hire ...

    African Journals Online (AJOL)

    This paper examines the duties of the seller under the Hire Purchase and Credit Sale Act 1964 (the Act) and under the Civil Code respectively as to the quiet enjoyment of the goods purchased, the right of the seller to sell them and the duty of the seller as to their merchantable quality. A comparison is made between these ...

  18. The religion under the rule of aesthetics

    Directory of Open Access Journals (Sweden)

    Alberto da Silva Moreira


    Full Text Available This article examines the modern process of aestheticization of culture and religion as consequent unfolding of the expansion of market rationality to the subjective life and the libidinal sphere of subjects. Its main objective is to inquire about the future of religion under the impact of sensation seeking culture and the inflation of aesthetics. Firstly, with the help of Türcke, Welsch, Foucault and Schultze´s investigate the aestheticization process of of social life, its causes and characteristics; Secondly, following Dufour, Türcke Leiss, Kline, Jhally e Welsch, it asks how the dynamics of aesthetical impacts the daily life and the bio-psychic economy of people; thirdly, it applies the results obtained to the analysis of what is happening with religion under the regime of aesthetics and sensational culture. Finally, it asks about the possible emancipatory potential of aestheticized own religious experience and tries to draw some further consequences for religion in the aesthetic field.

  19. Risk Management and Insurance Decisions under Ambiguity

    DEFF Research Database (Denmark)

    Martínez-Correa, Jimmy

    portfolio theory that assumes Subjective Expected Utility theory; however, it provides hints to a possible solution of the under-diversification puzzle of households. I also identify conditions under which more risk or ambiguity aversion decreases the demand for coinsurance. Additionally, I show......I study the impact of ambiguity on insurance decisions and the optimality of insurance contracts. My tractable approach allows me to study the interaction between risk and ambiguity attitudes. When insurance decisions are made independently of other assets, for a given increase in wealth, both risk...... and ambiguity attitudes interact in nontrivial ways to determine the change of coinsurance demand. I derive sufficient conditions to guarantee that the optimal coinsurance demand is decreasing in wealth. When a non-traded asset is introduced, my model predicts behavior that is inconsistent with the classical...

  20. Probabilistic decision graphs for optimization under uncertainty

    DEFF Research Database (Denmark)

    Jensen, Finn V.; Nielsen, Thomas Dyhre


    This paper provides a survey on probabilistic decision graphs for modeling and solving decision problems under uncertainty. We give an introduction to influence diagrams, which is a popular framework for representing and solving sequential decision problems with a single decision maker. As the me......This paper provides a survey on probabilistic decision graphs for modeling and solving decision problems under uncertainty. We give an introduction to influence diagrams, which is a popular framework for representing and solving sequential decision problems with a single decision maker...... the development of alternative representation languages, which enlarge the class of decision problems that can be modeled efficiently. We present some of these alternative frameworks and demonstrate their expressibility using several examples. Finally, we provide a list of software systems that implement...

  1. Anomalous effects of dense matter under rotation (United States)

    Huang, Xu-Guang; Nishimura, Kentaro; Yamamoto, Naoki


    We study the anomaly induced effects of dense baryonic matter under rotation. We derive the anomalous terms that account for the chiral vortical effect in the low-energy effective theory for light Nambu-Goldstone modes. The anomalous terms lead to new physical consequences, such as the anomalous Hall energy current and spontaneous generation of angular momentum in a magnetic field (or spontaneous magnetization by rotation). In particular, we show that, due to the presence of such anomalous terms, the ground state of the quantum chromodynamics (QCD) under sufficiently fast rotation becomes the "chiral soliton lattice" of neutral pions that has lower energy than the QCD vacuum and nuclear matter. We briefly discuss the possible realization of the chiral soliton lattice induced by a fast rotation in noncentral heavy ion collisions.

  2. Utilities' ''obligation to serve'' under deregulation

    International Nuclear Information System (INIS)

    Alexander, C.B.


    The utility no longer has protected status, and the traditional franchise concept is under attack. Exclusive rights once conveyed to the utilities are being denied and not just in the area of gas sales. Exclusive rights once conveyed to utilities will be denied in more areas. State by state, the utilities' franchise is being examined to see which, if any, of its provisions are necessary in a deregulated environment. Can the free market provide everything that's been provided for many years under monopolistic arrangements? Some of the most critical and difficult of these provisions concern the obligation to serve, which utilities, in most states, have assumed as part of their franchise agreement. Regulators, courts, utilities, marketers and others are busy sorting through these issues, but resolution could take years. The paper discusses deregulation, universal service fee, representation without taxation, suppliers and marketer restrictions

  3. The Kaiser Wilhelm Society under National Socialism

    CERN Document Server

    Sachse, Carola; Walker, Mark


    During the first part of the twentieth century, German science led the world. The most important scientific institution in Germany was the Kaiser Wilhelm Society, including institutes devoted to different fields of scientific research. These researchers were not burdened by teaching obligations and enjoyed excellent financial and material support. When the National Socialists came to power in Germany, all of German society, including science, was affected. The picture that previously dominated our understanding of science under National Socialism from the end of the Second World War to the recent past - a picture of leading Nazis ignorant and unappreciative of modern science and of scientists struggling to resist the Nazis - needs to be revised. This book surveys the history of Kaiser Wilhelm Institutes under Hitler, illustrating definitively the cooperation, if not collaboration, between scientists and National Socialists in order to further the goals of autarky, racial hygiene, war, and genocide.

  4. Pollution Under Environmental Regulation in Energy Markets

    CERN Document Server

    Gullì, Francesco


    Pollution Under Environmental Regulation in Energy Markets provides a study of environmental regulation when energy markets are imperfectly competitive. This theoretical treatment focuses on three relevant cases of energy markets. First, the residential space heating sector where hybrid regulation such as taxation and emissions trading together are possible. Second, the electricity market where transactions are organized in the form of multi-period auctions. Third, namely natural gas (input) and electricity (output) markets where there is combined imperfect competition in vertical related energy markets.   The development of free or low carbon technologies supported by energy policies, aiming at increasing security of supply, is also explored whilst considering competition policies that reduce market power in energy markets thus improving market efficiency. Pollution Under Environmental Regulation in Energy Markets discusses the key issues of whether imperfect competition can lessen the ability of environmen...

  5. Decisions on new product development under uncertainties (United States)

    Huang, Yeu-Shiang; Liu, Li-Chen; Ho, Jyh-Wen


    In an intensively competitive market, developing a new product has become a valuable strategy for companies to establish their market positions and enhance their competitive advantages. Therefore, it is essential to effectively manage the process of new product development (NPD). However, since various problems may arise in NPD projects, managers should set up some milestones and subsequently construct evaluative mechanisms to assess their feasibility. This paper employed the approach of Bayesian decision analysis to deal with the two crucial uncertainties for NPD, which are the future market share and the responses of competitors. The proposed decision process can provide a systematic analytical procedure to determine whether an NPD project should be continued or not under the consideration of whether effective usage is being made of the organisational resources. Accordingly, the proposed decision model can assist the managers in effectively addressing the NPD issue under the competitive market.

  6. Lower head integrity under steam explosion loads

    Energy Technology Data Exchange (ETDEWEB)

    Theofanous, T.G.; Yuen, W.W.; Angelini, S.; Freeman, K.; Chen, X.; Salmassi, T. [Center for Risk Studies and Safety, Univ. of California, Santa Barbara, CA (United States); Sienicki, J.J.


    Lower head integrity under steam explosion loads in an AP600-like reactor design is considered. The assessment is the second part of an evaluation of the in-vessel retention idea as a severe accident management concept, the first part (DOE/ID-10460) dealing with thermal loads. The assessment is conducted in terms of the Risk Oriented Accident Analysis Methodology (ROAAM), and includes the comprehensive evaluation of all relevant severe accident scenarios, melt conditions and timing of release from the core region, fully 3D mixing and explosion wave dynamics, and lower head fragility under local, dynamic loading. All of these factors and brought together in a ROAAM Probabilistic Framework to evaluate failure likelihood. The conclusion is that failure is `physically unreasonable`. (author)

  7. External costs of electricity production under scrutiny

    International Nuclear Information System (INIS)

    Wagner, H.J.; Melchert, A.


    After a short introduction into the problems and questions surrounding the issue of external costs Chapter 2 presents the most important results of the studies under review and analysis in this work. Occasionally, minor discrepancies were found between the results given in the summary of a study and the data reported in the relevant chapters. Chapter 3 identifies and discusses differences in perspective between the studies under consideration. Chapter 4 analyses the most important premises and parameters adopted in the studies for the calculation of overall costs and net benefits of the different modes of electricity production. This serves to probe the reliability of the data, plausibility of the premises, and nature of the presupposed relationships. Chapter 5 examines the relationships of time assumed in the studies and gives a first comment on the more advanced Prognos study. Chapter 6, finally, offers a summarizing evaluation. (orig./UA) [de

  8. ESR melting under constant voltage conditions

    Energy Technology Data Exchange (ETDEWEB)

    Schlienger, M.E.


    Typical industrial ESR melting practice includes operation at a constant current. This constant current operation is achieved through the use of a power supply whose output provides this constant current characteristic. Analysis of this melting mode indicates that the ESR process under conditions of constant current is inherently unstable. Analysis also indicates that ESR melting under the condition of a constant applied voltage yields a process which is inherently stable. This paper reviews the process stability arguments for both constant current and constant voltage operation. Explanations are given as to why there is a difference between the two modes of operation. Finally, constant voltage process considerations such as melt rate control, response to electrode anomalies and impact on solidification will be discussed.

  9. UKAEA underlying research programme annual report

    International Nuclear Information System (INIS)

    Moon, D.P.


    Investment in fundamental research is essential to the success of an organisation such as Atomic Energy Authority (AEA) Technology whose business is the selling of Research and Development (R and D) and the services relating to it. Such research supplies the scientific understanding that underpins the technical expertise of the organisation, develops new skills and techniques, and stimulates technical innovation. The resulting scientific and technical excellence is the hall-mark of a major contract R and D organisation. Fundamental research in the AEA is co-ordinated through the Underlying Research Programme. This Report describes progress made during the financial year 1988/89 within all Technical Areas of the Programme, and additionally summarises the AEA's Underlying Research on the Safe Integral Reactor design and on 'Cold Fusion'. Highlights of recent technical achievements within the Programme are described in a separate brochure. (author)

  10. Flexible MOFs under stress: pressure and temperature. (United States)

    Clearfield, Abraham


    In the recent past an enormous number of Metal-Organic Framework type compounds (MOFs) have been synthesized. The novelty resides in their extremely high surface area and the ability to include additional features to their structure either during synthesis or as additives to the MOF. This versatility allows for MOFs to be designed for specific applications. However, the question arises as to whether a particular MOF can withstand the stress that may be encountered in fulfillment of the designated application. In this study we describe the behavior of two flexible MOFs under pressure and several others under temperature increase. The pressure study includes both experimental and theoretical calculations. In the thermal processes evidence for colossal negative thermal expansion were encountered.

  11. Genes under positive selection in Escherichia coli

    DEFF Research Database (Denmark)

    Petersen, Lise; Bollback, Jonathan P; Dimmic, Matt


    We used a comparative genomics approach to identify genes that are under positive selection in six strains of Escherichia coli and Shigella flexneri, including five strains that are human pathogens. We find that positive selection targets a wide range of different functions in the E. coli genome......, including cell surface proteins such as beta barrel porins, presumably because of the involvement of these genes in evolutionary arms races with other bacteria, phages, and/or the host immune system. Structural mapping of positively selected sites on trans-membrane beta barrel porins reveals...... that the residues under positive selection occur almost exclusively in the extracellular region of the proteins that are enriched with sites known to be targets of phages, colicins, or the host immune system. More surprisingly, we also find a number of other categories of genes that show very strong evidence...

  12. Contact Sliding under Relatively Low Loads

    Directory of Open Access Journals (Sweden)

    Kyeong Hee Kang


    Full Text Available ZnO nanowires have received much interest owing to their particular structural and piezoelectric properties. For widespread application of ZnO nanowires in various nanotechnologies, the mechanical reliability of the nanowires should be assessed. In this paper, the damage characteristics of vertically grown ZnO nanowires due to contact sliding against a 2 mm diameter steel ball under relatively low loads were investigated. Frictional behavior and wear characteristics of the specimens were assessed. Furthermore, contact sliding tests were performed inside an SEM to monitor the progression of damage of the nanowires. It was found that the friction coefficient was about 0.35 under all loads while the damage characteristics of the nanowires were quite different for each load. The large diameter nanowires tended to fracture earlier than the small diameter nanowires. Wear tests performed inside the SEM confirmed the surface damage characteristics observed during the friction tests.

  13. Dynamics of anisotropic particles under waves (United States)

    Dibenedetto, Michelle; Ouellette, Nicholas; Koseff, Jeffrey


    We present results on anisotropic particles in wavy flows in order to gain insight into the transport and mixing of microplastic particles in the near-shore environment. From theory and numerical simulations, we find that the rate of alignment of the particles is not constant and depends strongly on their initial orientation; thus, variations in initial particle orientation result in dispersion of anisotropic-particle plumes. We find that this dispersion is a function of the particle's eccentricity and the ratio of the settling and wave time scales. Experiments in which non-spherical particles of various shapes are released under surface gravity waves were also performed. Our main goal is to explore the effects of particle shape under various wave scenarios. We vary the aspect ratio of the particle in our experiments while holding other variables constant. Our results demonstrate that particle shape can be important when predicting transport.

  14. Atomic collisions under extreme conditions in space

    International Nuclear Information System (INIS)

    Itikawa, Yukikazu


    In space, atoms and molecules are often placed under the extreme conditions which are very difficult to be realized on Earth. For instance, extremely hot and dense plasmas are found in and around various stellar objects (e.g., neutron stars) on one hand and extremely cold and diffuse gases prevail in interstellar space on the other. There is so strong a magnetic field that electron clouds in atoms and molecules are distorted. The study of atomic collisions under the extreme conditions is not only helpful in understanding the astrophysical environment but also reveals new aspects of the physics of atoms and molecules. This paper is an invitation to the study. (References are not exhaustive but only provide a clue with which more details can be found.) (author)

  15. Investment choice under uncertainty: A review essay

    Directory of Open Access Journals (Sweden)

    Trifunović Dejan


    Full Text Available An investment opportunity whose return is perfectly predictable, hardly exists at all. Instead, investor makes his decisions under conditions of uncertainty. Theory of expected utility is the main analytical tool for description of choice under uncertainty. Critics of the theory contend that individuals have bounded rationality and that the theory of expected utility is not correct. When agents are faced with risky decisions they behave differently, conditional on their attitude towards risk. They can be risk loving, risk averse or risk neutral. In order to make an investment decision it is necessary to compare probability distribution functions of returns. Investment decision making is much simpler if one uses expected values and variances instead of probability distribution functions.

  16. Numerical modeling of materials under extreme conditions

    CERN Document Server

    Brown, Eric


    The book presents twelve state of the art contributions in the field of numerical modeling of materials subjected to large strain, high strain rates, large pressure and high stress triaxialities, organized into two sections. The first part is focused on high strain rate-high pressures such as those occurring in impact dynamics and shock compression related phenomena, dealing with material response identification, advanced modeling incorporating microstructure and damage, stress waves propagation in solids and structures response under impact. The latter part is focused on large strain-low strain rates applications such as those occurring in technological material processing, dealing with microstructure and texture evolution, material response at elevated temperatures, structural behavior under large strain and multi axial state of stress.

  17. Analysis of driver performance under reduced visibility (United States)

    Kaeppler, W. D.


    Mathematical models describing vehicle dynamics as well as human behavior may be useful in evaluating driver performance and in establishing design criteria for vehicles more compatible with man. In 1977, a two level model of driver steering behavior was developed, but its parameters were identified for clear visibility conditions only. Since driver performance degrades under conditions of reduced visibility, e.g., fog, the two level model should be investigated to determine its applicability to such conditions. The data analysis of a recently performed driving simulation experiment showed that the model still performed reasonably well under fog conditions, although there was a degradation in its predictive capacity during fog. Some additional parameters affecting anticipation and lag time may improve the model's performance for reduced visibility conditions.

  18. Swash Zone Response under Various Wave Regimes

    DEFF Research Database (Denmark)

    Vicinanza, Diego; Baldock, Tom; Contestabile, Pasquale


    The modelling of swash zone (SZ) sediment transport and the resulting morphodynamics have been areas of active research over the last decade. However, many details are still to be understood, whose knowledge will be greatly advanced by the collection of high-quality data under the controlled large......-scale laboratory conditions. The research describes tests carried out in the large wave flume of the Maritime Engineering Laboratory at Catalonia University of Technology, to investigate the SZ under the storm conditions. Its main aim was to compare beach-profile responses for monochromatic waves, monochromatic...... waves plus free long waves, bi-chromatic waves and random waves. Both erosive and accretive conditions were considered. Results discussed here were derived from the analysis of only a part of the whole data set....

  19. Gas Bubble Dynamics under Mechanical Vibrations (United States)

    Mohagheghian, Shahrouz; Elbing, Brian


    The scientific community has a limited understanding of the bubble dynamics under mechanical oscillations due to over simplification of Navier-Stockes equation by neglecting the shear stress tensor and not accounting for body forces when calculating the acoustic radiation force. The current work experimental investigates bubble dynamics under mechanical vibration and resulting acoustic field by measuring the bubble size and velocity using high-speed imaging. The experimental setup consists of a custom-designed shaker table, cast acrylic bubble column, compressed air injection manifold and an optical imaging system. The mechanical vibrations resulted in accelerations between 0.25 to 10 times gravitational acceleration corresponding to frequency and amplitude range of 8 - 22Hz and 1 - 10mm respectively. Throughout testing the void fraction was limited to definition of Bjerknes force in combination with Rayleigh-Plesset equation. Physical behavior of the system was capture and classified. Bubble size, velocity as well as size and spatial distribution will be presented.

  20. Querying metabolism under different physiological constraints. (United States)

    Cakmak, Ali; Ozsoyoglu, Gultekin; Hanson, Richard W


    Metabolism is a representation of the biochemical principles that govern the production, consumption, degradation, and biosynthesis of metabolites in living cells. Organisms respond to changes in their physiological conditions or environmental perturbations (i.e. constraints) via cooperative implementation of such principles. Querying inner working principles of metabolism under different constraints provides invaluable insights for both researchers and educators. In this paper, we propose a metabolism query language (MQL) and discuss its query processing. MQL enables researchers to explore the behavior of the metabolism with a wide-range of predicates including dietary and physiological condition specifications. The query results of MQL are enriched with both textual and visual representations, and its query processing is completely tailored based on the underlying metabolic principles.

  1. Pollen selection under acid rain stress

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y.


    To investigate whether acid rain stress induces pollen selection in nature, three different approaches were used, based on the assumption that the response of pollen grains to acid rain is controlled by an acid sensitive gene product. Germination of pollen from homozygous and heterozygous individuals under acid rain stress was examined to detect any differences in rate of germination between populations of homogeneous and heterogeneous pollen grains. In vitro and in vivo bulked segregant analysis using RAPDs was used to search for differences in DNA constitution between the survivors of acid rain stressed and non-acid rain stressed pollen populations in vitro and between the progenies of acid rain stressed and non-acid rain stressed populations during pollination, respectively. No evidence for the pollen selection under acid rain stress was obtained in any of the test systems. Inhibition of protein synthesis using cycloheximide led to significant reduction of tube elongation at 4 hr and had no effect on pollen germination at any time interval tested. Total proteins extracted from control and acid rain stressed pollen grain populations exhibited no differences. The reduction of corn pollen germination in vitro under acid rain stress was mainly due to pollen rupture. The present data indicates the reduction of pollen germination and tube growth under acid rain stress may be a physiological response rather than a genetic response. A simple, nontoxic, and effective method to separate germinated from ungerminated pollen grains has been developed using pollen from corn (Zea mays, L. cv. Pioneer 3747). The separated germinated pollen grains retained viability and continued tube growth when placed in culture medium.

  2. Location Verification Systems Under Spatially Correlated Shadowing


    Yan, Shihao; Nevat, Ido; Peters, Gareth W.; Malaney, Robert


    The verification of the location information utilized in wireless communication networks is a subject of growing importance. In this work we formally analyze, for the first time, the performance of a wireless Location Verification System (LVS) under the realistic setting of spatially correlated shadowing. Our analysis illustrates that anticipated levels of correlated shadowing can lead to a dramatic performance improvement of a Received Signal Strength (RSS)-based LVS. We also analyze the per...

  3. Embedded System Synthesis under Memory Constraints

    DEFF Research Database (Denmark)

    Madsen, Jan; Bjørn-Jørgensen, Peter


    This paper presents a genetic algorithm to solve the system synthesis problem of mapping a time constrained single-rate system specification onto a given heterogeneous architecture which may contain irregular interconnection structures. The synthesis is performed under memory constraints, that is......, the algorithm takes into account the memory size of processors and the size of interface buffers of communication links, and in particular the complicated interplay of these. The presented algorithm is implemented as part of the LY-COS cosynthesis system....

  4. Essays on Decision Making under Uncertainty


    Sautua, Santiago Ignacio


    This dissertation consists of three chapters about decision making under uncertainty.Chapter 1: “Testing between Models of Smoking Risk Perceptions”Research in social and health psychology reports that smokers systematically underestimate the personal smoking risk. I build a model that captures potential determinants of smoking risk perceptions to investigate how smoking may cause an underestimation of the risk. The model is based on the premise that smokers have an incentive to be optimistic...

  5. Discovering biological progression underlying microarray samples.

    Directory of Open Access Journals (Sweden)

    Peng Qiu


    Full Text Available In biological systems that undergo processes such as differentiation, a clear concept of progression exists. We present a novel computational approach, called Sample Progression Discovery (SPD, to discover patterns of biological progression underlying microarray gene expression data. SPD assumes that individual samples of a microarray dataset are related by an unknown biological process (i.e., differentiation, development, cell cycle, disease progression, and that each sample represents one unknown point along the progression of that process. SPD aims to organize the samples in a manner that reveals the underlying progression and to simultaneously identify subsets of genes that are responsible for that progression. We demonstrate the performance of SPD on a variety of microarray datasets that were generated by sampling a biological process at different points along its progression, without providing SPD any information of the underlying process. When applied to a cell cycle time series microarray dataset, SPD was not provided any prior knowledge of samples' time order or of which genes are cell-cycle regulated, yet SPD recovered the correct time order and identified many genes that have been associated with the cell cycle. When applied to B-cell differentiation data, SPD recovered the correct order of stages of normal B-cell differentiation and the linkage between preB-ALL tumor cells with their cell origin preB. When applied to mouse embryonic stem cell differentiation data, SPD uncovered a landscape of ESC differentiation into various lineages and genes that represent both generic and lineage specific processes. When applied to a prostate cancer microarray dataset, SPD identified gene modules that reflect a progression consistent with disease stages. SPD may be best viewed as a novel tool for synthesizing biological hypotheses because it provides a likely biological progression underlying a microarray dataset and, perhaps more importantly, the

  6. Ring oscillator switching noise under NBTI wearout


    Fernández García, Raúl; Gil Galí, Ignacio; Ruiz, José María; Morata Cariñena, Marta


    In this paper the switching noise of a CMOS ring oscillator has been analysed when their pFETs are subjected to negative bias temperature instability (NBTI). The impact of pFET under NBTI has been experimentally quantified whereas CMOS ring oscillator frequency and the switching noise has been analysed by means of electrical full-model simulation. The results show that the impact on the electromagnetic compatibility behaviour increases with NBTI wearout. Peer Reviewed

  7. The ecophysiology of under-ice fauna


    Aarset, Arne V.


    During exposure to low salinity, the under-ice amphipods Gammarus wilkitzkii and Onisimus glacialis appeared as euryhaline osmoregulators, displaying regulation of haemolymph concentrations of sodium and chloride. Free amino acids took part in the regulation. During freezing and brine formation, the amphipods were freeze-sensitive and did not tolerate being frozen into solid ice. However, they could stay in the vicinity of the ice, conforming osmotically to the ambient brine and thus lowering...

  8. The resource theory under conditioned thermal operations


    Narasimhachar, Varun; Gour, Gilad


    The "thermal operations" framework developed in past works is used to model the evolution of microscopic quantum systems in contact with thermal baths. Here we extend this model to bipartite devices with one part acting as a control external to the system--bath setup. We define the operations of such hybrid devices as conditioned thermal operations. We examine the resource under these operations, which we call conditional athermality. In the quasiclassical limit, we quantify this resource and...

  9. Seismic load experiments under mean seismic excitation

    International Nuclear Information System (INIS)

    Steinhilber, H.; Jehlicka, P.; Malcher, L.


    The seismic load experiments carried out within the framework of the HDR safety programme are aimed at enlarging and verifying the know-how with regard to the design of nuclear power plants so as to protect them against the impact of earth-quakes. One of the main objectives is to find out computing methods yielding sufficiently reliable results defining the actual vibrational behaviour of real structures under high seismic excitation. (orig./GL) [de

  10. Oil exports under GATT and the WTO

    International Nuclear Information System (INIS)

    Abdallah, H.


    This paper will try to focus on two aspects of oil production policy under the General Agreement on Tariffs and Trade (GATT) and the World Trade Organization. The first is how freely an oil producer can regulate the quantity of oil production and exports without violating GATT rules and the second is how an oil exporter could benefit from GATT rules to overstep barriers to market access imposed by oil-importing countries. (author)

  11. Generating natural language under pragmatic constraints

    CERN Document Server

    Hovy, Eduard H


    Recognizing that the generation of natural language is a goal- driven process, where many of the goals are pragmatic (i.e., interpersonal and situational) in nature, this book provides an overview of the role of pragmatics in language generation. Each chapter states a problem that arises in generation, develops a pragmatics-based solution, and then describes how the solution is implemented in PAULINE, a language generator that can produce numerous versions of a single underlying message, depending on its setting.

  12. Modeling of STATCOM under different loading conditions

    DEFF Research Database (Denmark)

    George, G.J.; Ramachandran, Rakesh; Kowsalya, M.


    This paper deals with the study and analysis of Flexible AC Transmission Systems (FACTS), mainly the modeling of STATCOM. Reactive Power Compensation plays a very important role in the transmission of Electric Power. A comparative study of how the reactive power is injected into the transmission ...... system with and without STATCOM under different loading condition is also illustrated in this paper. Simulations are performed using MATLAB/SIMULINK software....

  13. New aquaculture drugs under FDA review (United States)

    Bowker, James D.; Gaikowski, Mark P.


    Only eight active pharmaceutical ingredients available in 18 drug products have been approved by the U.S. Food and Drug Administration for use in aquaculture. The approval process can be lengthy and expensive, but several new drugs and label claims are under review. Progress has been made on approvals for Halamid (chloramine-T), Aquaflor (florfenicol) and 35% PeroxAid (hydrogen peroxide) as therapeutic drugs. Data are also being generated for AQUI-S 20E, a fish sedative.

  14. Climate indices of Iran under climate change


    alireza kochaki; mehdi nasiry; gholamali kamali


    Global warming will affect all climatic variables and particularly rainfall patterns. The purpose of present investigation was to predict climatic parameters of Iran under future climate change and to compare them with the present conditions. For this reason, UKMO General Circulation Model was used for the year 2025 and 2050. By running the model, minimum and maximum monthly temperature and also maximum monthly rainfall for the representative climate stations were calculated and finally the e...

  15. How Wigner functions transform under symplectic maps

    International Nuclear Information System (INIS)

    Dragt, A.J.; Habib, S.


    It is shown that, while Wigner and Liouville functions transform in an identical way under linear symplectic maps, in general they do not transform identically for nonlinear symplectic maps. Instead there are quantum corrections whose ℎ → 0 limit may be very complicated. Examples of the behavior of Wigner functions in the ℎ → 0 limit are given in order to examine to what extent the corresponding Liouville densities are recovered

  16. How Wigner functions transform under symplectic maps

    Energy Technology Data Exchange (ETDEWEB)

    Dragt, A.J. [Univ. of Maryland, College Park, MD (United States). Center for Theoretical Physics; Habib, S. [Los Alamos National Lab., NM (United States). Theoretical Div.


    It is shown that, while Wigner and Liouville functions transform in an identical way under linear symplectic maps, in general they do not transform identically for nonlinear symplectic maps. Instead there are quantum corrections whose {Dirac_h} {r_arrow} 0 limit may be very complicated. Examples of the behavior of Wigner functions in the {Dirac_h} {r_arrow} 0 limit are given in order to examine to what extent the corresponding Liouville densities are recovered.

  17. Keeping parasitology under the One Health umbrella. (United States)

    Robertson, Lucy J; Utaaker, Kjersti Selstad; Goyal, Kapil; Sehgal, Rakesh


    The One Health concept is no longer new, but remains an accepted concept in modern disease control - where the interactions between animal health, human health, and the environment in which we live are recognised as being of importance. However, emerging infectious diseases often garner the greatest attention and resources. Parasitic infections, many of which are zoonotic but cannot truly be considered as emerging, must ensure that they retain their place under the One Health umbrella. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Water Demand Under Alternative Price Structures


    Sheila Olmstead; W. Michael Hanemann; Robert N. Stavins


    We estimate the price elasticity of water demand with household-level data, structurally modeling the piecewise-linear budget constraints imposed by increasing-block pricing. We develop a mathematical expression for the unconditional price elasticity of demand under increasing-block prices and compare conditional and unconditional elasticities analytically and empirically. We test the hypothesis that price elasticity may depend on price structure, beyond technical differences in elasticity co...

  19. Developing the comprehensive audit under PPS. (United States)

    Rezaee, Z


    In the area of auditing, the change in payment systems from a cost-based retrospective reimbursement system to PPS has forced the independent auditor and the hospital financial manager to focus on tight administrative and accounting controls. Overall, the key for the auditor under PPS seems to be development of a strategic, comprehensive audit plan. It can provide both control and structure while not producing restrictions.

  20. Neural dynamics underlying emotional transmissions between individuals


    Golland, Yulia; Levit-Binnun, Nava; Hendler, Talma; Lerner, Yulia


    Abstract Emotional experiences are frequently shaped by the emotional responses of co-present others. Research has shown that people constantly monitor and adapt to the incoming social–emotional signals, even without face-to-face interaction. And yet, the neural processes underlying such emotional transmissions have not been directly studied. Here, we investigated how the human brain processes emotional cues which arrive from another, co-attending individual. We presented continuous emotional...

  1. Revisiting the Factors Underlying Maxillary Midline Diastema

    Directory of Open Access Journals (Sweden)

    Abdullah M. Zakria Jaija


    Full Text Available Aim. The aim of this study is to analyze the etiological factors underlying the presence of maxillary midline diastema in a sample of orthodontic patients. Materials and Methods. One hundred patients who fulfill the inclusion criteria were selected from 1355 patients seeking orthodontic treatment. The pretreatment orthodontic records were analyzed. The width of the maxillary midline diastema was measured clinically with a digital caliper at two levels: the mesioincisal angles of the central incisors and five millimeters from the incisal edge. The two measurements were averaged, and patients with diastema of more than 0.5 millimeter in width were enrolled. Results. Diastema is a multifactorial clinical finding with more than one underlying etiological cause. The interrelationship between the familial pattern of midline diastema and the microdontia, macroglossia, labial frenum, and alveolar cleft conforms was clear. The effect of a mesiodens and the upper lateral incisor whether bilaterally missing, unerupted, or peg shaped was minimal. Conclusion. Etiological factors underlying maxillary midline diastema are interconnected. Using a checklist as a guide during handling maxillary midline diastema is important in the different stages of treatment.

  2. Research on budget management under IT environment

    Directory of Open Access Journals (Sweden)

    Wenchang Li


    Full Text Available IT technology has become a key element of core competitiveness of enterprises, and also the basis for its daily operation. The budget is a management process of forecasting and planning of the future operation and financial activities under the guidance of the strategic objectives, and completion of the strategic objectives to a maximum extent. Whether both of them can be effectively combined with is the key to effective implementation of the budget. Through analysis of the existing problems of the traditional budget of the enterprise and the budget under the information technology environment, analysis of the internal and external influencing factors of the budget management of the large and medium sized enterprises under the current environment with SWOT, factor quantization and weight with AHP, development of the strategic program according to the priority of weight, and finally verification with a case, this paper concludes that, the budget management work can be more strategic and forward-looking through combination with AHP and SWOT analysis.

  3. Radiopacities in dentine under amalgam restorations. (United States)

    Rudolphy, M P; van Amerongen, J P; ten Cate, J M


    Radiopacities, caused by tin or zinc deposits in partly demineralized dental tissue, are frequently seen under amalgam restorations. The aim of this study was to determine to what extent these radiopaque areas could be identified by Caries Detector (1% acid red in propylene glycol) which is claimed to stain the irreversibly demineralized dentine. Twenty-eight extracted teeth showing radiopacities under amalgam fillings were selected. The restorations were removed, and Caries Detector was applied. Caries was excavated until the dentine did no longer stain with the Caries Detector. Standardized radiographs were taken at different stages. In all teeth the radiopaque areas stained with the Caries Detector. Visual inspection of the radiographs, taken after excavation, revealed that the radiopacities had disappeared completely in 6 teeth; in 5 teeth a very small part of the radiopaque area remained; in 17 teeth the cavity floor appeared as a thin white line on X-ray. Overall, line scan analysis confirmed the data obtained by visual observation. The residual radiopacities and radiopaque lines were a very small fraction of the initial radiopacities. Therefore, it is concluded that the radiopaque zone under amalgam fillings represents almost entirely an area of irreversibly demineralized dentine as indicated by the Caries Detector.

  4. Climate policy under sustainable discounted utilitarianism

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, Simon [London School of Economics and Political Science (LSE) (United Kingdom); Asheim, Geir B. [Oslo Univ. (Norway). Dept. of Economics


    Empirical evaluation of policies to mitigate climate change has been largely confined to the application of discounted utilitarianism (DU). DU is controversial, both due to the conditions through which it is justified and due to its consequences for climate policies, where the discounting of future utility gains from present abatement efforts makes it harder for such measures to justify their present costs. In this paper, we propose sustainable discounted utilitarianism (SDU) as an alternative principle for evaluation of climate policy. Unlike undiscounted utilitarianism, which always assigns zero relative weight to present utility, SDU is an axiomatically based criterion, which departs from DU by assigning zero weight to present utility if and only if the present is better off than the future. Using the DICE integrated assessment model to run risk analysis, we show that it is possible for the future to be worse off than the present along a 'business as usual' development path. Consequently SDU and DU differ, and willingness to pay for emissions reductions is (sometimes significantly) higher under SDU than under DU. Under SDU, stringent schedules of emissions reductions increase social welfare, even for a relatively high utility discount rate. (orig.)

  5. Confined catalysis under two-dimensional materials (United States)

    Li, Haobo; Xiao, Jianping; Bao, Xinhe


    Confined microenvironments formed in heterogeneous catalysts have recently been recognized as equally important as catalytically active sites. Understanding the fundamentals of confined catalysis has become an important topic in heterogeneous catalysis. Well-defined 2D space between a catalyst surface and a 2D material overlayer provides an ideal microenvironment to explore the confined catalysis experimentally and theoretically. Using density functional theory calculations, we reveal that adsorption of atoms and molecules on a Pt(111) surface always has been weakened under monolayer graphene, which is attributed to the geometric constraint and confinement field in the 2D space between the graphene overlayer and the Pt(111) surface. A similar result has been found on Pt(110) and Pt(100) surfaces covered with graphene. The microenvironment created by coating a catalyst surface with 2D material overlayer can be used to modulate surface reactivity, which has been illustrated by optimizing oxygen reduction reaction activity on Pt(111) covered by various 2D materials. We demonstrate a concept of confined catalysis under 2D cover based on a weak van der Waals interaction between 2D material overlayers and underlying catalyst surfaces. PMID:28533413

  6. Bucket foundations under lateral cyclic loading

    DEFF Research Database (Denmark)

    Foglia, Aligi

    To enable a prosperous development of offshore wind energy, economically feasible technologies must be developed. The monopod bucket foundation is likely to become a cost-effective sub-structure for offshore wind turbines and has the potential to make offshore wind more cost-competitive in the en......To enable a prosperous development of offshore wind energy, economically feasible technologies must be developed. The monopod bucket foundation is likely to become a cost-effective sub-structure for offshore wind turbines and has the potential to make offshore wind more cost......-competitive in the energy market. This thesis addresses issues concerning monopod bucket foundations in the hope of providing tools and ideas that could be used to optimize the design of this sub-structure. The work is focussed on the behaviour of bucket foundations under lateral cyclic loading. Other related...... and propaedeutic topics, such as bucket foundations under transient lateral loading and under monotonic lateral loading, are also investigated. All the scientific work is fundamentally based on small-scale experimental tests of bucket foundations in dense water-saturated sand. The most important scientific...

  7. Soybean growth and yield under cover crops

    Directory of Open Access Journals (Sweden)

    Priscila de Oliveira


    Full Text Available The use of cover crops in no-tillage systems can provide better conditions for the development of soybean plants with positive effects on grain yield and growth analysis techniques allow researchers to characterize and understand the behavior of soybean plants under different straw covers. Thus, the aim of this study was to characterize, using growth analysis, yield components and agronomic performance of soybean under common bean, Brachiaria brizantha and pearl millet straws. The experiment was performed on a soil under cerrado in the municipality of Santo Antônio de Goiás, GO. The experiment was arranged in a randomized complete block design with three treatments (cover crops and five replications. Soybean grain yield was lower in the B. brizantha straw treatment (3,708 kg ha-1 than both in the pearl millet (4.772 kg ha-1 and common bean straw treatments (5,200 kg ha-1. The soybean growth analysis in B. brizantha, pearl millet and common bean allowed characterizing the variation in the production of dry matter of leaves, stems, pods and total and leaf area index that provided different grain yields. The cover crop directly affects the soybean grain yield.

  8. Higher Moments of Underlying Event Distributions

    CERN Document Server

    Xu, Zhen


    We perform an Underlying Event analysis for real data sets from pp collisions at center of mass energy $ \\sqrt{s}=5 $ and 13 TeV and pPb collisions at $ \\sqrt{s}=7 $ TeV at the LHC, together with the Monte Carlo data sets generated with Pythia8 and EPOS in the same conditions. The analysis is focused on the transverse region which is more sensitive to the Underlying Event, and performed as a function of the leading track transverse - momentum $p_t$ in each event. In our work, not only the average underlying event activity but also its fluctuation, namely its root mean square (RMS), Skewness and Kurtosis, are analyzed. We find that the particle density, energy density and their fluctuation magnitude (RMS) are suppressed at leading $p_t\\approx$ 5 GeV/c for all these cases, with EPOS having evident deviation of 10\\%-25\\%. The higher moments skewness and kurtosis decrease rapidly in low leading $p_t$ region, and follow an interesting Gaussian-like peak centered at leading $p_t\\approx$ 15 GeV/c.

  9. Monitoring Air Circulation Under Reduced Pressures (United States)

    Rygalov, Vadim

    Adequate air circulation is required for controlled environments to maintain uniform temperature and humidity control, and hence the ability to measure air flow accurately is important. Human and associated life support habitats (e.g.,. plant production systems) for future space missions will likely be operated at pressures less than 100 kPa to minimize gas leakage and structural mass. Under such reduced pressures, the outputs from conventional anemometers for monitoring air flow can change and require re-calibration. These effects of atmospheric pressure on different types of air flow measurements are not completely understood; hence we compared the performance of several air flow sensors across a range of hypobaric pressures. Sensors included a propeller type anemometer, a hot-wire anemometer, and a Pitot-tube based device. Theoretical schematics (including mathematical models) underlying these measurements were developed. Results demonstrated that changes in sensor outputs were predictable based on their operating principles, and that corrections could be developed for sensors calibrated under normal Earth atmosphere pressure ( 100 kPa) and then used at different pressures. The potential effects of hypobaric atmospheres and their altered air flows on plant physiology are also discussed.

  10. Efficient Bayesian inference under the structured coalescent. (United States)

    Vaughan, Timothy G; Kühnert, Denise; Popinga, Alex; Welch, David; Drummond, Alexei J


    Population structure significantly affects evolutionary dynamics. Such structure may be due to spatial segregation, but may also reflect any other gene-flow-limiting aspect of a model. In combination with the structured coalescent, this fact can be used to inform phylogenetic tree reconstruction, as well as to infer parameters such as migration rates and subpopulation sizes from annotated sequence data. However, conducting Bayesian inference under the structured coalescent is impeded by the difficulty of constructing Markov Chain Monte Carlo (MCMC) sampling algorithms (samplers) capable of efficiently exploring the state space. In this article, we present a new MCMC sampler capable of sampling from posterior distributions over structured trees: timed phylogenetic trees in which lineages are associated with the distinct subpopulation in which they lie. The sampler includes a set of MCMC proposal functions that offer significant mixing improvements over a previously published method. Furthermore, its implementation as a BEAST 2 package ensures maximum flexibility with respect to model and prior specification. We demonstrate the usefulness of this new sampler by using it to infer migration rates and effective population sizes of H3N2 influenza between New Zealand, New York and Hong Kong from publicly available hemagglutinin (HA) gene sequences under the structured coalescent. The sampler has been implemented as a publicly available BEAST 2 package that is distributed under version 3 of the GNU General Public License at © The Author 2014. Published by Oxford University Press.

  11. The intestinal microbiome of fish under starvation. (United States)

    Xia, Jun Hong; Lin, Grace; Fu, Gui Hong; Wan, Zi Yi; Lee, May; Wang, Le; Liu, Xiao Jun; Yue, Gen Hua


    Starvation not only affects the nutritional and health status of the animals, but also the microbial composition in the host's intestine. Next-generation sequencing provides a unique opportunity to explore gut microbial communities and their interactions with hosts. However, studies on gut microbiomes have been conducted predominantly in humans and land animals. Not much is known on gut microbiomes of aquatic animals and their changes under changing environmental conditions. To address this shortcoming, we determined the microbial gene catalogue, and investigated changes in the microbial composition and host-microbe interactions in the intestine of Asian seabass in response to starvation. We found 33 phyla, 66 classes, 130 orders and 278 families in the intestinal microbiome. Proteobacteria (48.8%), Firmicutes (15.3%) and Bacteroidetes (8.2%) were the three most abundant bacteria taxa. Comparative analyses of the microbiome revealed shifts in bacteria communities, with dramatic enrichment of Bacteroidetes, but significant depletion of Betaproteobacteria in starved intestines. In addition, significant differences in clusters of orthologous groups (COG) functional categories and orthologous groups were observed. Genes related to antibiotic activity in the microbiome were significantly enriched in response to starvation, and host genes related to the immune response were generally up-regulated. This study provides the first insights into the fish intestinal microbiome and its changes under starvation. Further detailed study on interactions between intestinal microbiomes and hosts under dynamic conditions will shed new light on how the hosts and microbes respond to the changing environment.

  12. Historical development of derivatives’ underlying assets

    Directory of Open Access Journals (Sweden)

    Sylvie Riederová


    Full Text Available The derivative transactions are able to eliminate the unexpected risk arising from the price volatility of the asset. The need for risk elimination relates to the application of derivatives.This paper is focused on derivatives’ underlying assets themselves. With the plain description, supported by progressive summarization, the authors analysed the relevant theoretical sources, dealt with derivatives, their underlying assets and their development in centuries. Starting in the ancient history, 2000 BC, the first non-standard transaction, very close to today’s understanding of derivatives, becomes to be closed between counterparties. During the time, in different kingdoms and emporiums, derivatives started to play a significant role in daily life, helping to reduce the uncertainty of the future. But the real golden era for derivatives started with the so called ‘New derivative markets’ and computer supported trading. They have extended their form from simple tools to most complex structures, without changing their main purpose hedging and risk – reduction.For the main purpose of this paper it is impossible to split the development of derivatives from the very wide extension of underlying assets. The change of these assets was one of the main drivers in derivatives development. Understanding of the dynamic character of these assets helps to understand the world of derivatives.

  13. Success factors of an enterprise under crisis

    Directory of Open Access Journals (Sweden)

    Yaroslava V Danilina


    Full Text Available Objective to analyze the impact of economic crisis in Russia on the enterprisesrsquo access to productive resources as well as on the level of their competencies. Methods historical abstractlogical. Results the article states that despite the influence of external factors the main activities of the company are internal capabilities and resources of the firm. It is shown that under crisis a company must adapt to the limited resources i.e. change the competences of using them. Under modern conditions the competitive advantage can be based on two components ndash access to resources and internal ability of the company to use them. Therefore under the resource constraints such competencies should be generated as 1 ability to use a smaller amount of resources 2 more efficient use of available resources 3 search for the new resources development of own resources. The study determined that the acquisition of new competencies by the company will be associated with the use and improvement of its cognitive capabilities which are a function of organizational and individual knowledge possessed by the enterprise i.e. its intellectual capital. The article analyses the experience of development of new competencies under crisis by the example of reorganization of quotPrompriborquot plant and activities of quotGalogenquot JSC. Analysis of the experience of these companies which not only survived during the crisis but also acquired new competences and skills have led to the conclusion that the key role in this process was played by working with the main part of a company39s intellectual capital i.e. human capital. Thus a conclusion is made about the value of people and their common interests during the transformations within the enterprise. Scientific novelty for the first time the cognitive aspects of the enterprisesrsquo modernization system are considered from the viewpoint of the new resource and competence theory of the enterprise. Practical significance the

  14. Polyamine biosynthesis in rice cultivars under salt stress and comparison with observations under drought stress

    Directory of Open Access Journals (Sweden)

    Phuc Thi Do


    Full Text Available Soil salinity affects a large proportion of rural area and limits agricultural productivity. To investigate differential adaptation to soil salinity, we studied salt tolerance of 18 varieties of Oryza sativa using a hydroponic culture system. Based on visual inspection and photosynthetic parameters, cultivars were classified according to their tolerance level. Additionally, biomass parameters were correlated with salt tolerance. Polyamines have frequently been demonstrated to be involved in plant stress responses and therefore soluble leaf polyamines were measured. Under salinity, putrescine (Put content was unchanged or increased in tolerant, while dropped in sensitive cultivars. Spermidine (Spd content was unchanged at lower NaCl concentrations in all, while reduced at 100 mM NaCl in sensitive cultivars. Spermine (Spm content was increased in all cultivars. A comparison with data from 21 cultivars under long-term, moderate drought stress revealed an increase of Spm under both stress conditions. While Spm became the most prominent polyamine under drought, levels of all three polyamines were relatively similar under salt stress. Put levels were reduced under both, drought and salt stress, while changes in Spd were different under drought (decrease or salt (unchanged conditions. Regulation of polyamine metabolism at the transcript level during exposure to salinity was studied for genes encoding enzymes involved in the biosynthesis of polyamines and compared to expression under drought stress. Based on expression profiles, investigated genes were divided into generally stress-induced genes (ADC2, SPD/SPM2, SPD/SPM3, one generally stress-repressed gene (ADC1, constitutively expressed genes (CPA1, CPA2, CPA4, SAMDC1, SPD/SPM1, specifically drought-induced genes (SAMDC2, AIH, one specifically drought-repressed gene (CPA3 and one specifically salt-stress repressed gene (SAMDC4, revealing both overlapping and specific stress responses under these

  15. Biotransformation of phytosterols under aerobic conditions. (United States)

    Dykstra, Christy M; Giles, Hamilton D; Banerjee, Sujit; Pavlostathis, Spyros G


    Phytosterols are plant-derived sterols present in pulp and paper wastewater and have been implicated in the endocrine disruption of aquatic species. Bioassays were performed to assess the effect of an additional carbon source and/or solubilizing agent on the aerobic biotransformation of a mixture of three common phytosterols (β-sitosterol, stigmasterol and campesterol). The aerobic biotransformation of the phytosterol mixture by a mixed culture developed from a pulp and paper wastewater treatment system was examined under three separate conditions: with phytosterols as the sole added carbon source, with phytosterols and dextrin as an additional carbon source, and with phytosterols added with ethanol as an additional carbon source and solubilizing agent. Significant phytosterol removal was not observed in assays set up with phytosterol powder, either with or without an additional carbon source. In contrast, all three phytosterols were aerobically degraded when added as a dissolved solution in ethanol. Thus, under the experimental conditions of this study, the bioavailability of phytosterols was limited without the presence of a solubilizing agent. The total phytosterol removal rate was linear for the first six days before re-spiking, with a rate of 0.47 mg/L-d (R(2) = 0.998). After the second spiking, the total phytosterol removal rate was linear for seven days, with a rate of 0.32 mg/L-d (R(2) = 0.968). Following the 7th day, the phytosterol removal rate markedly accelerated, suggesting two different mechanisms are involved in phytosterol biotransformation, more likely related to the production of enzyme(s) involved in phytosterol degradation, induced under different cell growth conditions. β-sitosterol was preferentially degraded, as compared to stigmasterol and campesterol, although all three phytosterols fell below detection limits by the 24th day of incubation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Percutaneous Nephrolithotomy under Spinal Anesthesia with Marcaine

    Directory of Open Access Journals (Sweden)

    S.M.R. Rabani


    Full Text Available Introduction & Objective: The efficacy of Percutaneous Nephrolithotomy (PCNL in the treatment of renal stones has been proven in its indications. The main method of anesthesia in this procedure is general anesthesia. We used spinal anesthesia (SA as an alternative method of anesthesia with many benefits. This study was intended to show the possibility of SA as a more comfortable method of anesthesia for the surgeon , the anesthesiologist and the patient via more cooperation of the patient during changing the position and prevention of some complications mostly in upper extremities and neck. Materials & Methods: In a prospective clinical trial study, a total of 112 patients underwent PCNL under SA with marcaine , from Nov 2004 till Feb 2009. Their mean age was 36 years (22-48, at first the syringe was stained by epinephrine and then 2 -3.5 ml marcaine was used for SA and addition of analgesics , sedatives or both., if needed. The rest of the procedure was done as routine.Results: Stone clearance was achieved in 82% of the patients and the rest were managed by ESWL. The mean operation time was 126 minutes (90-220, 36% of the patients needed sedation, analgesia, or both, specially those with bigger stones. 6% of the patients had upper pole stones .Blood transfusion was needed only in one patient. No significant complication was observed in this study.Conclusion: PCNL under SA afforded the surgeon and the anesthesiologist the opportunity of more patient cooperation during position changes and precludes some morbidities that may happen under general anesthesia because the patient is awake and able to portend.

  17. Optimizing BTEX biodegradation under denitrifying conditions

    International Nuclear Information System (INIS)

    Hutchins, S.R.


    Leaking underground storage tanks are a major source of ground water contamination by petroleum hydrocarbons. Gasoline and other fuels contain benzene, toluene, ethylbenzene, and xylenes (collectively known as BTEX), which are hazardous compounds, regulated by the U.S. Environmental Protection Agency (EPA). Laboratory tests were conducted to determine optimum conditions for benzene, toluene, ethylbenzene, and xylene (collectively known as BTEX) biodegradation by aquifer microorganisms under denitrifying conditions. Microcosms, constructed with aquifer samples from Traverse City, Michigan, were amended with selected concentrations of nutrients and one or more hydrocarbons. Toluene, ethylbenzene, m-xylene, and p-xylene, were degraded to below 5 micrograms/L when present as sole source substrates; stoichiometric calculations indicated that nitrate removal was sufficient to account for 70 to 80% of the compounds being mineralized. o-Xylene was recalcitrant when present as a sole source substrate, but was slowly degraded in the presence of the other hydrocarbons. Benzene was not degraded within one year, regardless of whether it was available as a sole source substrate or in combination with toluene, phenol, or catechol. Pre-exposure to low levels of BTEX and nutrients had variable effects, as did the addition of different concentrations of ammonia and phosphate. Nitrate concentrations as high as 500 mg/L NO3-N were slightly inhibitory. These data indicate that nitrate-mediated biodegradation of BTEX at Traverse City can occur under a variety of environmental conditions with rates relatively independent of nutrient concentrations. However, the data reaffirm that benzene is recalcitrant under strictly anaerobic conditions in these samples

  18. Dune growth under multidirectional wind regimes (United States)

    Gadal, C.; Rozier, O.; Claudin, P.; Courrech Du Pont, S.; Narteau, C.


    Under unidirectional wind regimes, flat sand beds become unstable to produce periodic linear dunes, commonly called transverse dunes because their main ridges are oriented perpendicular to the air flow. In areas of low sediment availability, the same interactions between flow, transport and topography produce barchan dunes, isolated sand-pile migrating over long distances with a characteristic crescentic shape. For the last fifteen years, barchan dunes and the instability at the origin of transverse dunes have been the subject of numerous studies that have identified a set of characteristic length and time scales with respect to the physical properties of both grains and fluid. This is not the case for dunes developing under multidirectional wind regimes. Under these conditions, dune orientation is measured with respect to the direction of the resultant sand flux. Depending on the wind regime, dunes do not always line up perpendicularly to the resultant sand flux, but can also be at an oblique angle or even parallel to it. These oblique and longitudinal dunes are ubiquitous in all deserts on Earth and planetary bodies because of the seasonal variability of wind orientation. They are however poorly constrained by observations and there is still no complete theoretical framework providing a description of their orientation and initial wavelength. Here, we extend the linear stability analysis of a flat sand of bed done in two dimensions for a unidirectional flow to three dimensions and multidirectional flow regimes. We are able to recover transitions from transverse to oblique or longitudinal dune patterns according to changes in wind regimes. We besides give a prediction for the initial dune wavelength. Our results compare well to previous theory of dune orientation and to field, experimental and numerical data.

  19. Sea level adaptation decisions under uncertainty

    DEFF Research Database (Denmark)

    Thorarinsdottir, T. L.; Guttorp, P.; Drews, M.


    Sea level rise has serious consequences for harbor infrastructure, storm drains and sewer systems, and many other issues. Adapting to sea level rise requires comparing different possible adaptation strategies, comparing the cost of different actions (including no action), and assessing where...... and at what point in time the chosen strategy should be implemented. All these decisions must be made under considerable uncertainty—in the amount of sea level rise, in the cost and prioritization of adaptation actions, and in the implications of no action. Here we develop two illustrative examples...

  20. Continental drift under the Third Reich. (United States)

    Buffetaut, Eric


    Contrary to what happened in many other countries in the 1930s and 1940s, Alfred Wegener's theory of continental drift was not generally rejected in Nazi Germany, although several leading German geologists of the time did not accept it. It was actually presented as the modern view of Earth history in books and magazine articles aimed at the general public. Although outlandish geological theories such as Hörbiger's Welteislehre were favoured by some Nazi dignitaries, they were not widely accepted in scientific circles. On the other hand, continental drift received official support under the Third Reich, at a time when it was ignored or ridiculed by most earth scientists outside Germany.

  1. Frequent price changes under menu costs

    DEFF Research Database (Denmark)

    Hansen, Per Svejstrup


    This paper investigates the effect of uncertainty on a single firm's pricing behaviour in a dynamic menu cost model that results in (S,s)-rules where the price is fixed inside a band. It will be demonstrated that even though the band of inaction widens in response to increased uncertainty......, the price may be changed more frequent in the short run, and in the long run it definitely will. Hence, observing frequent price changes is not necessarily inconsistent with a firm operating under menu costs. This paper relies on an article by Dixit (1991), (Review of Economic studies, 58, 141...

  2. Classical system underlying a diffracting quantum billiard (United States)

    Jain, Manan


    For a point scatterer placed slightly off the centre of a circular enclosure, rays are found which vividly exhibit the effect of diffraction. The Schrödinger equation was mapped in the complex plane by employing a fractional linear transformation which brings the point scatterer to the centre. But the mass of the particle becomes a function of space coordinates, bearing anisotropy. For the transformed problem, the corresponding classical Hamiltonian is written and solved with Snell's laws on the boundary. The solutions of the Hamilton's equations thus found constitute, in fact, the ray-manifold underlying the diffraction at the level of the wave description.

  3. Radioactive hospital wastes. Radiations under control

    International Nuclear Information System (INIS)

    Bondeelle, A.; Delmotte, H.; Gauron, C.


    A set of articles proposes an overview of legal and regulatory evolutions regarding radioactive hospital wastes. These legal measures and evolutions are notably present in the Public Health code, in the Labour code. An article outlines the role of the radiation protection expert in the process of elimination of contaminated wastes (four major steps for this elimination are indicated; peculiarities of the hospital are outlined, as well as control procedures and the importance of training and information). An article describes the specific activity of the Creteil incinerator which comprises a unit for the incineration of care activity wastes under a very constraining regulation

  4. Physical and chemical mechanisms underlying hematoma evolution

    International Nuclear Information System (INIS)

    Cho, K.J.; Fanders, B.L.; Smid, A.R.; McLaughlin, P.


    Angiostat, a new collagen embolic material supplied at a concentration of 35 mg/ml (Target Therapeutics, Los Angeles) was used for flow-directed hepatic artery embolization in a series of rabbits to examine its acute effects on hepatic microcirculation. Arteriograms were obtained both before and after embolization. The aorta and portal vein were perfused with two different colors of Microfil after the animals were killed,. Cleared liver specimens were examined under a dissection microscope. Extent of dearterialization, status of portal sinusoidal perfusion, and collateral formation after embolization with Angiostat were evaluated. Results will be compared with results achieved using other liquid and particulate embolic agents

  5. Stability of germanene under tensile strain

    KAUST Repository

    Kaloni, Thaneshwor P.


    The stability of germanene under biaxial tensile strain and the accompanying modifications of the electronic properties are studied by density functional theory. The phonon spectrum shows that up to 16% strain the germanene lattice is stable, where the Dirac cone shifts towards higher energy and hole-doped Dirac states are achieved. The latter is due to weakening of the Ge-Ge bonds and reduction of the s-p hybridization. Our calculated Grüneisen parameter shows a similar dependence on the strain as reported for silicene (which is different from that of graphene). © 2013 Elsevier B.V. All rights reserved.

  6. Topology of polymer chains under nanoscale confinement. (United States)

    Satarifard, Vahid; Heidari, Maziar; Mashaghi, Samaneh; Tans, Sander J; Ejtehadi, Mohammad Reza; Mashaghi, Alireza


    Spatial confinement limits the conformational space accessible to biomolecules but the implications for bimolecular topology are not yet known. Folded linear biopolymers can be seen as molecular circuits formed by intramolecular contacts. The pairwise arrangement of intra-chain contacts can be categorized as parallel, series or cross, and has been identified as a topological property. Using molecular dynamics simulations, we determine the contact order distributions and topological circuits of short semi-flexible linear and ring polymer chains with a persistence length of l p under a spherical confinement of radius R c . At low values of l p /R c , the entropy of the linear chain leads to the formation of independent contacts along the chain and accordingly, increases the fraction of series topology with respect to other topologies. However, at high l p /R c , the fraction of cross and parallel topologies are enhanced in the chain topological circuits with cross becoming predominant. At an intermediate confining regime, we identify a critical value of l p /R c , at which all topological states have equal probability. Confinement thus equalizes the probability of more complex cross and parallel topologies to the level of the more simple, non-cooperative series topology. Moreover, our topology analysis reveals distinct behaviours for ring- and linear polymers under weak confinement; however, we find no difference between ring- and linear polymers under strong confinement. Under weak confinement, ring polymers adopt parallel and series topologies with equal likelihood, while linear polymers show a higher tendency for series arrangement. The radial distribution analysis of the topology reveals a non-uniform effect of confinement on the topology of polymer chains, thereby imposing more pronounced effects on the core region than on the confinement surface. Additionally, our results reveal that over a wide range of confining radii, loops arranged in parallel and cross

  7. Central limit theorems under special relativity. (United States)

    McKeague, Ian W


    Several relativistic extensions of the Maxwell-Boltzmann distribution have been proposed, but they do not explain observed lognormal tail-behavior in the flux distribution of various astrophysical sources. Motivated by this question, extensions of classical central limit theorems are developed under the conditions of special relativity. The results are related to CLTs on locally compact Lie groups developed by Wehn, Stroock and Varadhan, but in this special case the asymptotic distribution has an explicit form that is readily seen to exhibit lognormal tail behavior.

  8. Lattice dynamics of solid xenon under pressure. (United States)

    Dewhurst, J K; Ahuja, R; Li, S; Johansson, B


    We use density-functional perturbation theory to obtain the phonon spectrum of fcc xenon under pressure. Thermodynamic properties obtained within the quasiharmonic approximation are in fair to good agreement with experiment at zero pressure. The transition pressure from the fcc to hcp phase is predicted to occur at 5 GPa. The fcc structure is found to be dynamically stable up to a pressure of 100 GPa, beyond which the phonon modes at the X and L symmetry points soften. We attribute the observed sluggish kinetics of the fcc-hcp transition to the small energy difference between the phases as well as to the high dynamical stability of the fcc phase.

  9. Ultimate Strength of Ship Hulls under Torsion

    DEFF Research Database (Denmark)

    Paik, Jeom Kee; Thayamballi, Anil K.; Pedersen, Preben Terndrup


    subjected to torsion. A procedure for calculating these stresses is briefly described. As an illustrative example, the distribution and magnitude of warping and shear stresses for a typical container vessel hull cross section under unit torsion is calculated by the procedure. By theoretical and numerical...... analyses, it is shown that the influence of torsion induced warping stresses on the ultimate hull girder bending strength is small for ductile hull materials while torsion induced shear stresses will of course reduce the ship hull ultimate bending moment....

  10. Phase instability in crystals under irradiation

    International Nuclear Information System (INIS)

    Martin, G.


    A diffusion term is introduced in the standard chemical rate model of the defect population in crystals under irradiation. For point defect generation rates larger than a critical value (g*), the uniform point defect population is shown to be unstable with respect to spatial fluctuations of the point defect concentration. g* is temperature dependent. Severala effects including the nucleation of arrays of point defect clusters, or radiation induced precipitation may occur above the instability threshold. Defect-defect interaction potentials play a crucial role in the numerical value of this threshold [fr

  11. Electromagnetic radiation under explicit symmetry breaking. (United States)

    Sinha, Dhiraj; Amaratunga, Gehan A J


    We report our observation that radiation from a system of accelerating charges is possible only when there is explicit breaking of symmetry in the electric field in space within the spatial configuration of the radiating system. Under symmetry breaking, current within an enclosed area around the radiating structure is not conserved at a certain instant of time resulting in radiation in free space. Electromagnetic radiation from dielectric and piezoelectric material based resonators are discussed in this context. Finally, it is argued that symmetry of a resonator of any form can be explicitly broken to create a radiating antenna.

  12. Getting under the skin of epidermal morphogenesis. (United States)

    Fuchs, Elaine; Raghavan, Srikala


    At the surface of the skin, the epidermis serves as the armour for the body. Scientists are now closer than ever to understanding how the epidermis accomplishes this extraordinary feat, and is able to survive and replenish itself under the harshest conditions that face any tissue. By combining genetic engineering with cell-biological studies and with human genome data analyses, skin biologists are discovering the mechanisms that underlie the development and differentiation of the epidermis and hair follicles of the skin. This explosion of knowledge paves the way for new discoveries into the genetic bases of human skin disorders and for developing new therapeutics.

  13. Optimal Asset Allocation under Quadratic Loss Aversion


    Fortin, Ines; Hlouskova, Jaroslava


    Abstract: We study the asset allocation of a quadratic loss-averse (QLA) investor and derive conditions under which the QLA problem is equivalent to the mean-variance (MV) and conditional value-at-risk (CVaR) problems. Then we solve analytically thetwo-asset problem of the QLA investor for a risk-free and a risky asset. We find that the optimal QLA investment in the risky asset is finite, strictly positive and is minimal with respect to the reference point for a value strictly larger than the...

  14. On user behaviour adaptation under interface change

    CSIR Research Space (South Africa)

    Rosman, Benjamin S


    Full Text Available stream_source_info Rosman2_2014_ABSTRACT ONLY.pdf.txt stream_content_type text/plain stream_size 2213 Content-Encoding UTF-8 stream_name Rosman2_2014_ABSTRACT ONLY.pdf.txt Content-Type text/plain; charset=UTF-8... International Conference on Intelligent User Interfaces, Haifa, Israel, 24-27 February 2014 On User Behaviour Adaptation Under Interface Change Benjamin Rosman_ Subramanian Ramamoorthy M. M. Hassan Mahmud School of Informatics University of Edinburgh...

  15. Stellarator optimization under several criteria using metaheuristics

    International Nuclear Information System (INIS)

    Castejón, F; Gómez-Iglesias, A; Vega-Rodríguez, M A; Jiménez, J A; Velasco, J L; Romero, J A


    A new algorithm based on metaheuristics has been developed to perform stellarator optimization. This algorithm, which is inspired by the behaviour of bees and is called distributed asynchronous bees, has been used for the optimization under three criteria: minimization of B × grad(B) drift, Mercier and ballooning stability. This algorithm is tested by partially optimizing TJ-II and, afterwards, a three-period optimized configuration is found by performing a full optimization that starts from a three-period heliac. (paper)

  16. Corruption and optimal regulation under common agency

    Directory of Open Access Journals (Sweden)

    Pedro Hemsley


    Full Text Available I show that it is optimal to separate non-benevolent regulators when regulated projects are large. Separation prevents regulators from coordinating to appropriate all of the agent's informational rent when they know the type of the latter; therefore, there is a trade-off between saving on informational rent and efficiency, since the game between the regulators induced by separation causes further distortions when compared to the allocation under one regulator. When the informational rent at stake is large due to the size of the project, separation is the optimal institutional answer.

  17. Uranium dioxide restructuration under irradiation. Furet program

    International Nuclear Information System (INIS)

    Stora, J.P.; Hueber, C.


    A complete model of fuel restructuration under irradiation was built on the basis of many short irradiation experiments carried out in Siloe at Grenoble between 1970 and 1973. From the experiments, carefully temperature and power controlled, a precise relationship was established between the microstructure and temperature conditions. The main points studied were: the type of recrystallization as a function of density; restructuration and displacements of matter tending to central hole formation; healing of cracks and thermal take-up of clearance and efficiency of thermal cycles and mechanical take-up of clearance [fr

  18. Strength of concrete structures under dynamic loading (United States)

    Kumpyak, O. G.; Galyautdinov, Z. R.; Kokorin, D. N.


    The use of elastic supports is one the efficient methods of decreasing the dynamic loading. The paper describes the influence of elastic supports on the stress-strain state of steel concrete structures exposed to one-time dynamic loading resulting in failure. Oblique bending beams on elastic supports and their elastic, elastoplastic, and elastoplastic consolidation behavior are considered in this paper. For numerical calculations the developed computer program is used based on the finite element method. Research findings prove high efficiency of elastic supports under dynamic loading conditions. The most effective behavior of elastic supports is demonstrated at the elastoplastic stage. A good agreement is observed between the theoretical and experimental results.

  19. What causes dark circles under the eyes? (United States)

    Freitag, Fernanda Magagnin; Cestari, Tania Ferreira


    Dark circles under the eyes (DC) are defined as bilateral, round, homogeneous pigment macules on the infraorbital regions. Despite its significant prevalence, there are a few published studies about its pathogenesis. DC are caused by multiple etiologic factors that include dermal melanin deposition, postinflammatory hyperpigmentation secondary to atopic or allergic contact dermatitis, periorbital edema, superficial location of vasculature, and shadowing due to skin laxity. The purpose of this review is to discuss some of the available evidences about the anatomic features that could explain dark circles and the proposed treatments for this unpleasant condition.

  20. Supply chain network design under uncertainty

    DEFF Research Database (Denmark)

    Govindan, Kannan; Fattahi, Mohammad; Keyvanshokooh, Esmaeil


    Supply chain network design (SCND) is one of the most crucial planning problems in supply chain management (SCM). Nowadays, design decisions should be viable enough to function well under complex and uncertain business environments for many years or decades. Therefore, it is essential to make...... programming, risk-averse stochastic programming, robust optimization, and fuzzy mathematical programming are explored in terms of mathematical modeling and solution approaches. Finally, the drawbacks and missing aspects of the related literature are highlighted and a list of potential issues for future...

  1. Growth of zircaloy 4 under neutron flux

    International Nuclear Information System (INIS)

    Morize, P.; Baicry, J.; Morlot, G.; Sciers, P.; Lehmann, D.


    Between 300 and 385 0 C, and under neutron fluxes between 0.5 and 2.10 14 n/cm 2 /s, the growth of zircaloy tubes is nil in the plane perpendicular to the axis, and can be represented by the equation: Δl/l=4.6610 -14 (phit)sup(0.49) in the axial direction. In the area investigated, neither the irradiation temperature nor the instantaneous flux has any effect on the metallurgical state (relieved or recrystallized) [fr

  2. Evaluation consolidated under Financial Group Banca Transilvania

    Directory of Open Access Journals (Sweden)

    Chebac Neculina


    Full Text Available One of the components of prudence measures adopted by the competentauthorities with the regulation and supervision of financial markets at national andEuropean level is mandatory consolidation of accounts. Romania as member of theEuropean Union it harmonized national regulations with the European consolidation ofaccounts of companies. For the banks have been issued by the appropriate rules by theregulators authority, concerned by National Bank of Romania. In accordance withnational regulations, companies are required to prepare annual consolidated financialstatements may make such situations according to the regulations or accounting inaccordance with Directive VII of the European Economic Community, underInternational Financial Reporting Standards.

  3. Spatial analysis and planning under imprecision

    CERN Document Server

    Leung, Y


    The book deals with complexity, imprecision, human valuation, and uncertainty in spatial analysis and planning, providing a systematic exposure of a new philosophical and theoretical foundation for spatial analysis and planning under imprecision. Regional concepts and regionalization, spatial preference-utility-choice structures, spatial optimization with single and multiple objectives, dynamic spatial systems and their controls are analyzed in sequence.The analytical framework is based on fuzzy set theory. Basic concepts of fuzzy set theory are first discussed. Many numerical examples and emp

  4. Effectiveness of Nivea Sunscreen under Ultraviolet Light

    Directory of Open Access Journals (Sweden)

    Piset Virachunya


    Full Text Available The relationship between a sunscreen’s SPF and its absorbance for UV light of wavelength 240 to 320 was investigated. The investigation was conducted by diluting sunscreens with SPFs of 20, 30 and 50 and placing the solution in a spectrophotometer where the absorbance was measured under UVA, UVB and UVC light. It was shown that the sunscreen was effective over the whole range of wavelengths, with increased effectiveness at wavelengths 240 and 300. The results also show that as the SPF increased, the absorbance increased proportionally.

  5. Effectiveness of Nivea Sunscreen under Ultraviolet Light

    Directory of Open Access Journals (Sweden)

    Piset Virachunya


    Full Text Available The relationship between a sunscreen’s SPF and its absorbance for UV light of wavelength 240 to 320 was investigated. The investigation was conducted by diluting sunscreens with SPF's of 20, 30 and 50 and placing the solution in a spectrophotometer where the absorbance was measured under UVA, UVB and UVC light. It was shown that the sunscreen was effective over the whole range of wavelengths, with increased effectiveness at wavelengths 240 and 300. The results also show that as the SPF increased, the absorbance increased proportionally.

  6. Heart rate variability analysed by Poincaré plot in patients with metabolic syndrome. (United States)

    Kubičková, Alena; Kozumplík, Jiří; Nováková, Zuzana; Plachý, Martin; Jurák, Pavel; Lipoldová, Jolana


    The SD1 and SD2 indexes (standard deviations in two orthogonal directions of the Poincaré plot) carry similar information to the spectral density power of the high and low frequency bands but have the advantage of easier calculation and lesser stationarity dependence. ECG signals from metabolic syndrome (MetS) and control group patients during tilt table test under controlled breathing (20 breaths/minute) were obtained. SD1, SD2, SDRR (standard deviation of RR intervals) and RMSSD (root mean square of successive differences of RR intervals) were evaluated for 31 control group and 33 MetS subjects. Statistically significant lower values were observed in MetS patients in supine position (SD1: p=0.03, SD2: p=0.002, SDRR: p=0.006, RMSSD: p=0.01) and during tilt (SD2: p=0.004, SDRR: p=0.007). SD1 and SD2 combining the advantages of time and frequency domain methods, distinguish successfully between MetS and control subjects. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Heart rhythm complexity impairment in patients undergoing peritoneal dialysis (United States)

    Lin, Yen-Hung; Lin, Chen; Ho, Yi-Heng; Wu, Vin-Cent; Lo, Men-Tzung; Hung, Kuan-Yu; Liu, Li-Yu Daisy; Lin, Lian-Yu; Huang, Jenq-Wen; Peng, Chung-Kang


    Cardiovascular disease is one of the leading causes of death in patients with advanced renal disease. The objective of this study was to investigate impairments in heart rhythm complexity in patients with end-stage renal disease. We prospectively analyzed 65 patients undergoing peritoneal dialysis (PD) without prior cardiovascular disease and 72 individuals with normal renal function as the control group. Heart rhythm analysis including complexity analysis by including detrended fractal analysis (DFA) and multiscale entropy (MSE) were performed. In linear analysis, the PD patients had a significantly lower standard deviation of normal RR intervals (SDRR) and percentage of absolute differences in normal RR intervals greater than 20 ms (pNN20). Of the nonlinear analysis indicators, scale 5, area under the MSE curve for scale 1 to 5 (area 1-5) and 6 to 20 (area 6-20) were significantly lower than those in the control group. In DFA anaylsis, both DFA α1 and DFA α2 were comparable in both groups. In receiver operating characteristic curve analysis, scale 5 had the greatest discriminatory power for two groups. In both net reclassification improvement model and integrated discrimination improvement models, MSE parameters significantly improved the discriminatory power of SDRR, pNN20, and pNN50. In conclusion, PD patients had worse cardiac complexity parameters. MSE parameters are useful to discriminate PD patients from patients with normal renal function.

  8. Support Vector Machine Classification of Drunk Driving Behaviour. (United States)

    Chen, Huiqin; Chen, Lei


    Alcohol is the root cause of numerous traffic accidents due to its pharmacological action on the human central nervous system. This study conducted a detection process to distinguish drunk driving from normal driving under simulated driving conditions. The classification was performed by a support vector machine (SVM) classifier trained to distinguish between these two classes by integrating both driving performance and physiological measurements. In addition, principal component analysis was conducted to rank the weights of the features. The standard deviation of R-R intervals (SDNN), the root mean square value of the difference of the adjacent R-R interval series (RMSSD), low frequency (LF), high frequency (HF), the ratio of the low and high frequencies (LF/HF), and average blink duration were the highest weighted features in the study. The results show that SVM classification can successfully distinguish drunk driving from normal driving with an accuracy of 70%. The driving performance data and the physiological measurements reported by this paper combined with air-alcohol concentration could be integrated using the support vector regression classification method to establish a better early warning model, thereby improving vehicle safety.

  9. Dose-response relationship of baroreflex sensitivity and heart rate variability to individually-tailored exercise training in patients with heart failure. (United States)

    Iellamo, Ferdinando; Manzi, Vincenzo; Caminiti, Giuseppe; Sposato, Barbara; Massaro, Michele; Cerrito, Anna; Rosano, Giuseppe; Volterrani, Maurizio


    Heart Rate Variability (HRV) and Baroreflex Sensitivity (BRS) are impaired in patients with Chronic Heart Failure (CHF) and carry negative prognosis. Exercise training improves these parameters. However, the relationship between exercise training with HRV and BRS has been investigated without regard for individual training loads. We tested the hypothesis that in CHF patients changes in HRV and BRS are dose-response related to individual volume/intensity training load (TL). Twenty patients with stable postinfarction CHF under optimal medical treatment were randomized to either aerobic continuous training (ACT) or aerobic interval training (AIT) for 12weeks. Individualized TL was monitored by the Training Impulses (TRIMPi) method, which was determined using the individual HR and lactate profiling determined during a treadmill test at baseline. HRV (standard deviation of mean R-R interval) and BRS were assessed at rest and 3weeks apart, throughout the study. HRV, BRS and R-R interval increased significantly with training, being very highly correlated to the dose of exercise with a second-order regression model (r(2) ranged from 0.75 to 0.96; Ptraining in CHF patients are dose related to TL in a non-linear fashion on an individual basis, with optimal results at moderate doses of exercise. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  10. Geomagnetic storm under laboratory conditions: randomized experiment (United States)

    Gurfinkel, Yu I.; Vasin, A. L.; Pishchalnikov, R. Yu; Sarimov, R. M.; Sasonko, M. L.; Matveeva, T. A.


    The influence of the previously recorded geomagnetic storm (GS) on human cardiovascular system and microcirculation has been studied under laboratory conditions. Healthy volunteers in lying position were exposed under two artificially created conditions: quiet (Q) and storm (S). The Q regime playbacks a noise-free magnetic field (MF) which is closed to the natural geomagnetic conditions on Moscow's latitude. The S regime playbacks the initially recorded 6-h geomagnetic storm which is repeated four times sequentially. The cardiovascular response to the GS impact was assessed by measuring capillary blood velocity (CBV) and blood pressure (BP) and by the analysis of the 24-h ECG recording. A storm-to-quiet ratio for the cardio intervals (CI) and the heart rate variability (HRV) was introduced in order to reveal the average over group significant differences of HRV. An individual sensitivity to the GS was estimated using the autocorrelation function analysis of the high-frequency (HF) part of the CI spectrum. The autocorrelation analysis allowed for detection a group of subjects of study which autocorrelation functions (ACF) react differently in the Q and S regimes of exposure.

  11. Music and Astronomy Under the Stars (United States)

    Lubowich, D.


    Bring telescope to where the people are! Music and Astronomy Under the Stars is a public astronomy outreach program at community parks during and after free summer music concerts and outdoor movie nights. This project also includes daytime activities because there are some afternoon concerts and daylight children's concerts, and observations using remotely operated telescopes in cloudy weather. While there have been many astronomy outreach activities and telescope observations at city sidewalks and parks, this program targets a completely different audience---music lovers who are attending free summer concerts held in community parks. The music lovers who may never have visited a science museum, planetarium, or star party will be exposed to telescope observations and astronomy information with no additional travel costs. This program will permit the entire community to participate in telescope observations and view astronomical video information to enhance the public appreciation of astronomy. This program will also reach underrepresented and underserved groups (women, minorities, older adults). The population base for the initial target audience (Nassau and Suffolk Counties, New York) is 2,500,000. My partners are the Amateur Observers' Society of New York (AOS) and the Towns of Oyster Bay, Hempstead, North Hempstead, and Huntington. Music and Astronomy Under the Stars is program that should continue beyond the International Year of Astronomy 2009 (IYA2009) and can be expanded into a national program.

  12. CANDU fuel behaviour under transient conditions

    International Nuclear Information System (INIS)

    Segel, A.W.L.


    The Canadian R and D program to understand CANDU fuel behaviour under transient conditions is described. Fuel sheath behaviour studies have led to the development of a model of transient plastic strain in inert gas, which integrates the deformation due to several mechanisms. Verification tests demonstrated that on average the model overpredicts strain by 20%. From oxidation kinetics studies a sheath failure embrittlement criterion based on oxygen distribution has been developed. We have also established a rate equation for high-temperature stress-dependent crack formation due to embrittlement of the sheath by beryllium. An electric, simulated fuel element is being used in laboratory tests to characterize the behaviour of fuel in the horizontal. In-reactor, post-dryout tests have been done for several years. There is an axially-segmented, axisymmetric fuel element model in place and a fully two-dimensional code is under development. Laboratory testing of bundles, in its early stages, deals with the effects of geometric distortion and sheath-to-sheath interaction. In-reactor, post-dryout tests of CANDU fuel bundles with extensive central UO 2 melting did not result in fuel fragmentation nor damage to the pressure tube. (author)

  13. Nuclear waste under glass, further discussion (United States)

    O'Keefe, J. A.; Barkatt, A.; Glass, B. P.; Alterescu, S.

    J. J. Crovisier and J. Honnorez [1988] discuss an article by W. W. Maggs, “Mg May Protect Waste Under Glass” [Maggs, 1988] summarizing work by A. Barkatt (Catholic University, Washington, D.C.), B. P. Glass (University of Delaware, Newark), and S. Alterescu and J. A. O'Keefe (NASA/GSFC, Greenbelt, Md.). We found that seawater is orders of magnitude less corrosive t h an fresh water in attacking tektite glass; traced the protective effect to the presence of magnesium, at a level of about 1.3 g/L in seawater; and suggested that the effect might be useful in protecting nuclear waste glasses from corrosion.Crovisier and Honnorez first make the point that the rate of corrosion of glass is, in principle, a function of the ratio of surface area 5 to the effective volume V. This concept, which is usually discussed in American literature under the name of S/V effects, is discussed by Crovisier and Honnorez in terms of the “permeability of the environment.” These effects have been carefully considered throughout our work (see, for example, Barkatt et al. [19867rsqb;). It turns out that in the sea the effective S/V is so small that the effects referred to by Crovisier and Honnorez can be ignored.

  14. Studying leukocyte recruitment under flow conditions. (United States)

    Parsons, Sean A; Jurzinsky, Christophe; Cuvelier, Susan L; Patel, Kamala D


    Leukocyte recruitment from the vasculature occurs under conditions of haemodynamic shear stress. The parallel plate flow chamber apparatus is an in vitro system that is widely used to study leukocyte recruitment under shear conditions. The flow chamber is a versatile tool for examining adhesive interactions, as it can be used to study a variety of adhesive substrates, ranging from monolayers of primary cells to isolated adhesion molecules, and a variety of adhesive particles, ranging from leukocytes in whole blood to antibody-coated latex beads. We describe here methods for studying leukocyte recruitment to cytokine-stimulated, transfected or transduced endothelial cells using both whole blood and isolated leukocyte suspensions. These methods enable multiple parameters to be measured, including the total number of recruited leukocytes, the percentage of leukocytes that are rolling or firmly adherent, and the percentage of leukocytes that have transmigrated. Although these methods are described for interactions between leukocytes and endothelial cells, they are broadly applicable to the study of interactions between many combinations of adhesive substrates and adhesive particles.

  15. Wheat genotypes under different seeding rates

    Directory of Open Access Journals (Sweden)

    Luís César Vieira Tavares


    Full Text Available The wheat tillering capacity defines yield and yield components, being affected by seeding rate. This study aimed at evaluating wheat genotypes under different seeding rates, in Londrina and Ponta Grossa, Paraná State, Brazil, in 2009 and 2010. A completely randomized blocks design, in a factorial scheme, with four replications, was used. The agronomic traits of three wheat genotypes (PF 014384, BRS Tangará and BRS Pardela were evaluated under the seeding rates of 150 pl m-2, 250 pl m-2, 350 pl m-2 and 450 pl m-2. In Londrina, the maximum yield was observed at densities close to 270 pl m-2, while in Ponta Grossa (2009 there was a linear fit. There was no adjustment for plant height, concerning seeding rate. The number of ears per area (ears m-2 was higher in Ponta Grossa (2009 and did not differ between the locations, in 2010. In Ponta Grossa (2010, the highest one thousand seeds weight was estimated at the density of 341 pl m-2, while in Londrina (2010 it was estimated at 150 pl m-2 and 450 pl m-2. The seeding rate affected grain yield, depending on place and year. In Londrina, there was a limit for yield, concerning seeding rate. The one thousand seeds weight was influenced by seeding rate, depending on year and location. Plant height was affected by genotype and growing area.

  16. Multitask Quantile Regression under the Transnormal Model. (United States)

    Fan, Jianqing; Xue, Lingzhou; Zou, Hui


    We consider estimating multi-task quantile regression under the transnormal model, with focus on high-dimensional setting. We derive a surprisingly simple closed-form solution through rank-based covariance regularization. In particular, we propose the rank-based ℓ 1 penalization with positive definite constraints for estimating sparse covariance matrices, and the rank-based banded Cholesky decomposition regularization for estimating banded precision matrices. By taking advantage of alternating direction method of multipliers, nearest correlation matrix projection is introduced that inherits sampling properties of the unprojected one. Our work combines strengths of quantile regression and rank-based covariance regularization to simultaneously deal with nonlinearity and nonnormality for high-dimensional regression. Furthermore, the proposed method strikes a good balance between robustness and efficiency, achieves the "oracle"-like convergence rate, and provides the provable prediction interval under the high-dimensional setting. The finite-sample performance of the proposed method is also examined. The performance of our proposed rank-based method is demonstrated in a real application to analyze the protein mass spectroscopy data.

  17. Connections of Trapezoidal Sheets under Fire

    Directory of Open Access Journals (Sweden)

    P. Kallerová


    Full Text Available This paper describes two different experiments on connections of trapezoidal sheets under elevated temperatures. The first experiments were tensile tests carried out on four sets of tests with screwed connections under ambient and elevated temperatures. One diameter of self-drilling screws and three different thicknesses of trapezoidal sheets were used. The applied screws were without washers, or with sealed or steel washers. The second experiment was performed in a laboratory furnace to check the catenary action of a thin-walled trapezoidal sheet. The basic theory tested in this experiment was that in the first phase of the fire the sheet behaves as a simply supported beam, while in the second phase the load bearing is transferred by a tension membrane. These experiments will be used to develop a design model of connections at high temperatures. High fire resistance of the trapezoidal sheet, dependent on suitable design of the screwed connection to the bearing structure, was confirmed. The experiment with the simple beam also confirmed catenary action. 

  18. Concrete structures under impact and impulsive loading

    International Nuclear Information System (INIS)

    Plauk, G.


    This book contains papers contributed to the RILEM/CEB/IABSE/IASS-Interassociation Symposium on 'Concrete Structures under Impact and Impulsive Loading'. The essential aim of this symposium is to provide an international forum for the exchange of information on existing and current research relating to impact problems as well as to identify areas to which further research activities should be directed. The subject of the symposium is far ranging. Fifty five papers were proposed and arranged in six technical sessions, a task which sometimes posed difficulties for the Organization Committee and the Advisory Group, because some of the papers touched several topics and were difficult to integrate. However, we are confident that these minor difficulties were solved to the satisfaction of everyone involved. Each session of the symposium is devoted to a major subject area and introduced by a distinguished Introductory Reporter. The large international attendance, some 21 countries are represented, and the large number of excellent papers will certainly produce a lively discussion after each session and thus help to further close the gaps in our knowledge about the behaviour of structures and materials under impact and impulsive loading. (orig./RW)

  19. Tv nyheder: Journalistiske Idealer er under Pres

    DEFF Research Database (Denmark)

    Thomsen, Line Hassall


    som tv-journalisterne ville ønske det. Tv-journalister har mange store idealer om god journalistik og public service. Men de vilkår journalisterne arbejder under gør idealerne nærmest umulige at opnå i dagligdagen. I dag er det ikke de journalistiske idealer men markedskræfterne der driver de...... Journalist” inside Public Service TV Newsrooms in the UK and Denmark’. Under ph.d.- studiet har jeg tilbragt halvandet år med deltager-observation på de fire største tv-redaktioner i England og Danmark. Jeg har observeret og deltaget i det daglige arbejde på redaktionerne hos TV Avisen og TV2 Nyhederne og i...... licensfinansieret tv-station. Men der tog jeg fejl. Jeg ledte efter forskelligheder, men fandt ligheder. Efterhånden som feltstudiet tog fat gik det op for mig at journalisterne på de fire forskellige tv-stationer arbejdede og tænkte ens. Derudover gik det op for mig at mange af journalisterne på de forskelligt...

  20. Assessing reservoir operations risk under climate change (United States)

    Brekke, Levi D.; Maurer, Edwin P.; Anderson, Jamie D.; Dettinger, Michael D.; Townsley, Edwin S.; Harrison, Alan; Pruitt, Tom


    Risk-based planning offers a robust way to identify strategies that permit adaptive water resources management under climate change. This paper presents a flexible methodology for conducting climate change risk assessments involving reservoir operations. Decision makers can apply this methodology to their systems by selecting future periods and risk metrics relevant to their planning questions and by collectively evaluating system impacts relative to an ensemble of climate projection scenarios (weighted or not). This paper shows multiple applications of this methodology in a case study involving California's Central Valley Project and State Water Project systems. Multiple applications were conducted to show how choices made in conducting the risk assessment, choices known as analytical design decisions, can affect assessed risk. Specifically, risk was reanalyzed for every choice combination of two design decisions: (1) whether to assume climate change will influence flood-control constraints on water supply operations (and how), and (2) whether to weight climate change scenarios (and how). Results show that assessed risk would motivate different planning pathways depending on decision-maker attitudes toward risk (e.g., risk neutral versus risk averse). Results also show that assessed risk at a given risk attitude is sensitive to the analytical design choices listed above, with the choice of whether to adjust flood-control rules under climate change having considerably more influence than the choice on whether to weight climate scenarios.

  1. Sterically controlled mechanochemistry under hydrostatic pressure. (United States)

    Yan, Hao; Yang, Fan; Pan, Ding; Lin, Yu; Hohman, J Nathan; Solis-Ibarra, Diego; Li, Fei Hua; Dahl, Jeremy E P; Carlson, Robert M K; Tkachenko, Boryslav A; Fokin, Andrey A; Schreiner, Peter R; Galli, Giulia; Mao, Wendy L; Shen, Zhi-Xun; Melosh, Nicholas A


    Mechanical stimuli can modify the energy landscape of chemical reactions and enable reaction pathways, offering a synthetic strategy that complements conventional chemistry. These mechanochemical mechanisms have been studied extensively in one-dimensional polymers under tensile stress using ring-opening and reorganization, polymer unzipping and disulfide reduction as model reactions. In these systems, the pulling force stretches chemical bonds, initiating the reaction. Additionally, it has been shown that forces orthogonal to the chemical bonds can alter the rate of bond dissociation. However, these bond activation mechanisms have not been possible under isotropic, compressive stress (that is, hydrostatic pressure). Here we show that mechanochemistry through isotropic compression is possible by molecularly engineering structures that can translate macroscopic isotropic stress into molecular-level anisotropic strain. We engineer molecules with mechanically heterogeneous components-a compressible ('soft') mechanophore and incompressible ('hard') ligands. In these 'molecular anvils', isotropic stress leads to relative motions of the rigid ligands, anisotropically deforming the compressible mechanophore and activating bonds. Conversely, rigid ligands in steric contact impede relative motion, blocking reactivity. We combine experiments and computations to demonstrate hydrostatic-pressure-driven redox reactions in metal-organic chalcogenides that incorporate molecular elements that have heterogeneous compressibility, in which bending of bond angles or shearing of adjacent chains activates the metal-chalcogen bonds, leading to the formation of the elemental metal. These results reveal an unexplored reaction mechanism and suggest possible strategies for high-specificity mechanosynthesis.

  2. Sterically controlled mechanochemistry under hydrostatic pressure (United States)

    Yan, Hao; Yang, Fan; Pan, Ding; Lin, Yu; Hohman, J. Nathan; Solis-Ibarra, Diego; Li, Fei Hua; Dahl, Jeremy E. P.; Carlson, Robert M. K.; Tkachenko, Boryslav A.; Fokin, Andrey A.; Schreiner, Peter R.; Galli, Giulia; Mao, Wendy L.; Shen, Zhi-Xun; Melosh, Nicholas A.


    Mechanical stimuli can modify the energy landscape of chemical reactions and enable reaction pathways, offering a synthetic strategy that complements conventional chemistry. These mechanochemical mechanisms have been studied extensively in one-dimensional polymers under tensile stress using ring-opening and reorganization, polymer unzipping and disulfide reduction as model reactions. In these systems, the pulling force stretches chemical bonds, initiating the reaction. Additionally, it has been shown that forces orthogonal to the chemical bonds can alter the rate of bond dissociation. However, these bond activation mechanisms have not been possible under isotropic, compressive stress (that is, hydrostatic pressure). Here we show that mechanochemistry through isotropic compression is possible by molecularly engineering structures that can translate macroscopic isotropic stress into molecular-level anisotropic strain. We engineer molecules with mechanically heterogeneous components—a compressible (‘soft’) mechanophore and incompressible (‘hard’) ligands. In these ‘molecular anvils’, isotropic stress leads to relative motions of the rigid ligands, anisotropically deforming the compressible mechanophore and activating bonds. Conversely, rigid ligands in steric contact impede relative motion, blocking reactivity. We combine experiments and computations to demonstrate hydrostatic-pressure-driven redox reactions in metal-organic chalcogenides that incorporate molecular elements that have heterogeneous compressibility, in which bending of bond angles or shearing of adjacent chains activates the metal-chalcogen bonds, leading to the formation of the elemental metal. These results reveal an unexplored reaction mechanism and suggest possible strategies for high-specificity mechanosynthesis.

  3. Prediction of stress relaxation under multiaxial stresses

    International Nuclear Information System (INIS)

    Sandstroem, R.; Malen, K.; Otterberg, R.


    Computations have been made of the relaxation of residual stresses in a thick walled tube under conditions corresponding to commercial stress relief heat treatment of the nuclear reactor pressure vessel steel A533B. The distribution of residual stresses which were introduced was peaked around a given radius in the tube. The relax- ation of the equivalent stresses followed almost exactly a uniaxial behavior. The relaxation rate of the hydrostatic stress was of about the same order or slower than that of the equivalent stress. The time dependence of the hydrostatic stress was mainly controlled by the initial magnitude of hydrostatic stress whereas the degree of the constraint and thereby the boundary conditions at the tube walls had only a small influence. The relaxation rate decreased with increasing initial magnitude of the hydrostatic stress. The computed relaxation behaviour under multiaxial stress could be rationalized in terms of a developed model. This model was also suc- cessfully applied to Gott's measurements on stress relaxation during stress relief heat treatment of a welded joint between 130 mm thick plates of A533B where the stress state was highly triaxial. (Authors)

  4. Wind noise under a pine tree canopy. (United States)

    Raspet, Richard; Webster, Jeremy


    It is well known that infrasonic wind noise levels are lower for arrays placed in forests and under vegetation than for those in open areas. In this research, the wind noise levels, turbulence spectra, and wind velocity profiles are measured in a pine forest. A prediction of the wind noise spectra from the measured meteorological parameters is developed based on recent research on wind noise above a flat plane. The resulting wind noise spectrum is the sum of the low frequency wind noise generated by the turbulence-shear interaction near and above the tops of the trees and higher frequency wind noise generated by the turbulence-turbulence interaction near the ground within the tree layer. The convection velocity of the low frequency wind noise corresponds to the wind speed above the trees while the measurements showed that the wind noise generated by the turbulence-turbulence interaction is near stationary and is generated by the slow moving turbulence adjacent to the ground. Comparison of the predicted wind noise spectrum with the measured wind noise spectrum shows good agreement for four measurement sets. The prediction can be applied to meteorological estimates to predict the wind noise under other pine forests.

  5. Unidirectional spreading of oil under solid ice

    International Nuclear Information System (INIS)

    Weerasuriya, S.A.; Yapa, P.D.


    Equations are presented to describe the unidirectional spreading of oil under solid ice covers floating in calm water. These spreading equations are derived using a simplified form of the Navier-Stokes equations, and cover both the constant discharge and the constant volume modes. An equation for computing final slick length is also given. Laboratory experiments using physical models were conducted to verify the equations. The experiments used oils of different viscosities, ice cover roughnesses varying from smooth to rough, and a variety of discharge conditions. The emphasis of the study was on the dominant spreading mechanism for oil under ice, which is the buoyancy-viscous phase. The laboratory results agree closely with the theoretical predictions. Discrepancies can be attributed to the experimental difficulties and errors introduced from the assumptions made in deriving the theory. The equations presented will be useful in computing spreading rate during an accidental oil spill or in contingency planning. The equations are simple to use, suitable for hand calculations or for incorporation into numerical models for oil spill simulation. 24 refs., 10 figs., 1 tab

  6. Biotransformation of monoaromatic hydrocarbons under anoxic conditions

    International Nuclear Information System (INIS)

    Ball, H.A.; Reinhard, M.; McCarty, P.L.


    Aromatic hydrocarbons contained in gasoline are environmental pollutants of particular concern since they are relatively soluble in water, many are toxic, and some are confirmed carcinogens, (e.g., benzene). Although most gasoline constituents are readily degraded in aerobic surface water systems, the groundwater environment associated with hydrocarbon spills is typically anaerobic, thus precluding aerobic degradation pathways. In the absence of oxygen, degradation of gasoline components can take place only with the utilization of alternate electron acceptors such as nitrate, sulfate, carbon dioxide, and possibly ferric iron or other metal oxides. Benzene, toluene, and xylene isomers were completely degraded by aquifer- or sewage sludge-derived microorganisms under dentrifying and methanogenic conditions. Recently, a pure culture was found to degrade toluene and m-xylene nitrate or nitrous oxide as an electron acceptor. This paper presents initial results of ongoing study to develop and characterize microbial consortia capable of transforming aromatic hydrocarbons under nitrate-reducing conditions, and understand the effect of environmental factors on the biotransformation processes

  7. Behavior of clay materials under ionizing radiation

    International Nuclear Information System (INIS)

    Laine, Maxime


    The aim of this PhD thesis is to study and understand, by proposing reaction mechanisms, the behavior under irradiation of various clay materials. The systems of interest were first synthetic talc, which is the prototype of a non-swelling material. Under irradiation by accelerated electrons, the production of dihydrogen in this system, due solely to surface hydroxyl groups, is of the same order of magnitude as the one obtained in liquid water. This yield is divided by 30 in the case of natural talc from Luzenac, thus highlighting the importance of the impurities as scavengers of the precursors of dihydrogen. Synthetic smectites, which are swelling materials, were then studied. The results evidence the radiolysis of water confined in the interlayer space, leading to H 2 yields which may be two to three times higher than those measured in water. Moreover, they are similar for montmorillonite and saponite, evidencing that the charge location plays only a minor role. Finally, the study of double layered hydroxides or anionic clays shows that, in this case, the nature of the anion in the inter lamellar space controls the reactivity. Parallel to these measurements, electron paramagnetic spectroscopy experiments have enabled proposing reaction mechanisms. Finally, all these results are of interest in the context of the disposal of radioactive waste. (author) [fr

  8. Terrestrial ecosystems under warmer and drier climates (United States)

    Pan, Y.


    Future warmer and drier climates will likely affect many of the world's terrestrial ecosystems. These changes will fundamentally reshape terrestrial systems through their components and across organization levels. However, it is unclear to what extent terrestrial ecosystems would be resilient enough to stay put to increased temperature and water stress by only adjusting carbon fluxes and water balances? And to what extent it would reach the thresholds at which terrestrial ecosystems were forced to alter species compositions and ecosystem structures for adapting to newer climates? The energy balance of terrestrial ecosystems link thermal and water conditions to defines terrestrial carbon processes and feedbacks to climate, which will inevitably change under warmer and drier climates. Recent theoretical studies provide a new framework, suggesting that terrestrial ecosystems were capable of balancing costs of carbon gain and water transport to achieve optimums for functioning and distribution. Such a paradigm is critical for understanding the dynamics of future terrestrial ecosystems under climate changes, and facilitate modeling terrestrial ecosystems which needs generalized principles for formulating ecosystem behaviors. This study aims to review some recent studies that explore responses of terrestrial ecosystems to rather novel climate conditions, such as heat-induced droughts, intending to provide better comprehension of complex carbon-water interactions through plants to an ecosystem, and relevant factors that may alleviate or worsen already deteriorated climates such as elevated CO2 and soil conditions.

  9. New quantum criticality revealed under pressure

    International Nuclear Information System (INIS)

    Watanabe, Shinji; Miyake, Kazumasa


    Unconventional quantum critical phenomena observed in Yb-based periodic crystals such as YbRh 2 Si 2 and β-YbAlB 4 have been one of the central issues in strongly correlated electron systems. The common criticality has been discovered in the quasicrystal Yb 15 Au 51 Al 34 , which surprisingly persists under pressure at least up to P = 1.5 GPa. The T/H scaling where the magnetic susceptibility can be expressed as a single scaling function of the ratio of the temperature T to the magnetic field H has been discovered in the quasicrystal, which is essentially the same as that observed in β-YbAlB 4 . Recently, the T/H scaling as well as the common criticality has also been observed even in the approximant crystal Yb 14 Au 51 Al 35 under pressure. The theory of critical Yb-valence fluctuation gives a natural explanation for these striking phenomena in a unified way. (author)

  10. Intraoperative seizures during craniotomy under general anesthesia. (United States)

    Howe, John; Lu, Xiaoying; Thompson, Zoe; Peterson, Gordon W; Losey, Travis E


    An acute symptomatic seizure is a clinical seizure occurring at the time of or in close temporal association with a brain insult. We report an acute symptomatic seizure occurring during a surgical procedure in a patient who did not have a prior history of epilepsy and who did not have a lesion associated with an increased risk of epilepsy. To characterize the incidence and clinical features of intraoperative seizures during craniotomy under general anesthesia, we reviewed cases where continuous EEG was acquired during craniotomy. Records of 400 consecutive cases with propofol as general anesthesia during craniotomy were reviewed. Demographic data, indication for surgery, clinical history, history of prior seizures, duration of surgery and duration of burst suppression were recorded. Cases where seizures were observed were analyzed in detail. Two out of 400 patients experienced intraoperative seizures, including one patient who appeared to have an acute symptomatic seizure related to the surgical procedure itself and a second patient who experienced two seizures likely related to an underlying diagnosis of epilepsy. This is the first report of an acute symptomatic seizure secondary to a neurosurgical procedure. Overall, 0.5% of patients monitored experienced seizures, indicating that intraoperative seizures are rare, and EEG monitoring during craniotomies is of low yield in detecting seizures. Copyright © 2016. Published by Elsevier Ltd.

  11. Petroleum taxation under uncertainty - contingent claims

    International Nuclear Information System (INIS)

    Lund, D.


    A workable method for the analysis of incentive effects of petroleum taxes under uncertainty is presented. The main advantage of the method is that it concludes with a single number for the after-tax value of any development plan, and thus allows for a quantification of incentive effects for any given description of production possibilities. It is, however, not possible to describe tax effects under uncertainty by simple magnitudes independent of production possibilities, such as wedges in rates of return. The theoretical basis is the contingent claims analysis from finance theory, which is applicable in particular to companies that are owned by well-diversified shareholders. It is not obvious that the tax authorities of poorly diversified countries should value uncertain income streams by the same method. The Norwegian petroleum taxation is shown to have strongly distortionary effects compared to a no-tax situation or a cash flow tax. These distortions were reduced by the tax changes that followed the 1986 decreases in crude oil prices. A weakness of the model of the Norwegian system is that an exactly optimal financial policy for the company has not been found. 30 refs., 2 figs., 3 tabs

  12. Muon catalyzed fusion under compressive conditions

    International Nuclear Information System (INIS)

    Cripps, G.; Goel, B.; Harms, A.A.


    The viability of a symbiotic combination of Muon Catalyzed Fusion (μCF) and high density generation processes has been investigated. The muon catalyzed fusion reaction rates are formulated in the temperature and density range found under moderate compressive conditions. Simplified energy gain and power balance calculations indicate that significant energy gain occurs only if standard type deuterium-tritium (dt) fusion is ignited. A computer simulation of the hydrodynamics and fusion kinetics of a spherical deuterium-tritium pellet implosion including muons is performed. Using the muon catalyzed fusion reaction rates formulated and under ideal conditions, the pellet ignites (and thus has a significant energy gain) only if the initial muon concentration is approximately 10 17 cm -3 . The muons need to be delivered to the pellet within a very short-time (≅ 1 ns). The muon pulse required in order to make the high density and temperature muon catalyzed fusion scheme viable is beyond the present technology for muon production. (orig.) [de


    Directory of Open Access Journals (Sweden)

    C. Paotonan


    Full Text Available Geotube is, among others, a type of coastal structure that is increasingly accepted for coastal protection especially underwater breakwater. Besides its relatively low cost, it has other advantages such as flexibility, ease of construction and the fact that it can be filled with local sand material. Similar to all other coastal structures, it should also be stable under wave attack. A simple theoretical approach based on linear wave was adopted to estimate the stability of such structure. The theoretical solution was then compared with an experimental study. The experimental study was conducted at the Hydraulics and Hydrology Laboratory of Universitas Gadjah Mada. However, instead of a real geotube, PVC pipe was used where the weight of the PVC was varied by adjusting the volume of sand in the pipe. The result indicated that the agreement between the theoretical solution and the experiment was encouraging. The analytical solution may be utilized to predict underwater pipe stability under wave attack with certain degree of accuracy.

  14. Photochemical synthesis of biomolecules under anoxic conditions (United States)

    Folsome, Clair; Brittain, Andrew; Zelko, Michael


    We report the long-wavelength UV anoxic photosynthesis of uracil, various sugars (including deoxyribose and glycoaldehyde), amino acids, and other organic photoproducts. These reactions occur in mixtures of water, calcium carbonate, formaldehyde and hydrazine. Our data demonstrate that under several sets of conditions biomolecules can be formed in variety and abundance from reduced compounds (formaldehyde and hydrazine) derived from anoxic dinitrogen/carbon dioxide environments. The formaldehyde concentrations were varied from 10 mM to 0.005 mM, and the hydrazine concentrations were varied from 1 mM to 0.01 mM. The highest of these reactant concentrations were 500 and 6 times greater than those reported for earlier experiments upon the synthesis of these precursors from CO2 or N2, while the lowest of reactant concentrations employed here were 0.5 (formaldehyde) and 0.006 (hydrazine). Product yields were greatest when the hydrazine/formaldehyde ratio was 1, and when the reactant concentrations were low. These data suggest that organic products can be formed in variety from those amounts of formaldehyde and hydrazine precursors which are themselves formed under anoxic UV photochemical conditions. Hence these various reactions would seem to have prebiotic relevance. The UV 254 nm photon flux employed was 100 times higher than unattenuated solar flux. Durations of UV exposure were 24 hrs and 72 hrs. No experiments have been addressed to the possibility of UV flux dependency.

  15. Assessing reservoir operations risk under climate change (United States)

    Brekke, L.D.; Maurer, E.P.; Anderson, J.D.; Dettinger, M.D.; Townsley, E.S.; Harrison, A.; Pruitt, T.


    Risk-based planning offers a robust way to identify strategies that permit adaptive water resources management under climate change. This paper presents a flexible methodology for conducting climate change risk assessments involving reservoir operations. Decision makers can apply this methodology to their systems by selecting future periods and risk metrics relevant to their planning questions and by collectively evaluating system impacts relative to an ensemble of climate projection scenarios (weighted or not). This paper shows multiple applications of this methodology in a case study involving California's Central Valley Project and State Water Project systems. Multiple applications were conducted to show how choices made in conducting the risk assessment, choices known as analytical design decisions, can affect assessed risk. Specifically, risk was reanalyzed for every choice combination of two design decisions: (1) whether to assume climate change will influence flood-control constraints on water supply operations (and how), and (2) whether to weight climate change scenarios (and how). Results show that assessed risk would motivate different planning pathways depending on decision-maker attitudes toward risk (e.g., risk neutral versus risk averse). Results also show that assessed risk at a given risk attitude is sensitive to the analytical design choices listed above, with the choice of whether to adjust flood-control rules under climate change having considerably more influence than the choice on whether to weight climate scenarios. Copyright 2009 by the American Geophysical Union.

  16. Temperature of Steel Columns under Natural Fire

    Directory of Open Access Journals (Sweden)

    F. Wald


    Full Text Available Current fire design models for time-temperature development within structural elements as well as for structural behaviour are based on isolated member tests subjected to standard fire regimes, which serve as a reference heating, but do not model natural fire. Only tests on a real structure under a natural fire can evaluate future models of the temperature developments in a fire compartment, of the transfer of heat into the structure and of the overall structural behaviour under fire.To study overall structural behaviour, a research project was conducted on an eight storey steel frame building at the  Cardington Building Research Establishment laboratory on January 16, 2003. A fire compartment 11×7 m was prepared on the fourth floor. A fire load of 40 kg/m2 was applied with 100 % permanent mechanical load and 65 % of imposed load. The paper summarises the experimental programme and shows the temperature development of the gas in the fire compartment and of the fire protected columns bearing the unprotected floors.

  17. Expansive Soil Crack Depth under Cumulative Damage

    Directory of Open Access Journals (Sweden)

    Bei-xiao Shi


    Full Text Available The crack developing depth is a key problem to slope stability of the expansive soil and its project governance and the crack appears under the roles of dry-wet cycle and gradually develops. It is believed from the analysis that, because of its own cohesion, the expansive soil will have a certain amount of deformation under pulling stress but without cracks. The soil body will crack only when the deformation exceeds the ultimate tensile strain that causes cracks. And it is also believed that, due to the combined effect of various environmental factors, particularly changes of the internal water content, the inherent basic physical properties of expansive soil are weakened, and irreversible cumulative damages are eventually formed, resulting in the development of expansive soil cracks in depth. Starting from the perspective of volumetric strain that is caused by water loss, considering the influences of water loss rate and dry-wet cycle on crack developing depth, the crack developing depth calculation model which considers the water loss rate and the cumulative damages is established. Both the proposal of water loss rate and the application of cumulative damage theory to the expansive soil crack development problems try to avoid difficulties in matrix suction measurement, which will surely play a good role in promoting and improving the research of unsaturated expansive soil.

  18. Soil aggregation under different management systems

    Directory of Open Access Journals (Sweden)

    Cibele Mascioli Rebello Portella


    Full Text Available Considering that the soil aggregation reflects the interaction of chemical, physical and biological soil factors, the aim of this study was evaluate alterations in aggregation, in an Oxisol under no-tillage (NT and conventional tillage (CT, since over 20 years, using as reference a native forest soil in natural state. After analysis of the soil profile (cultural profile in areas under forest management, samples were collected from the layers 0-5, 5-10, 10-20 and 20-40 cm, with six repetitions. These samples were analyzed for the aggregate stability index (ASI, mean weighted diameter (MWD, mean geometric diameter (MGD in the classes > 8, 8-4, 4-2, 2-1, 1-0.5, 0.5-0.25, and < 0.25 mm, and for physical properties (soil texture, water dispersible clay (WDC, flocculation index (FI and bulk density (Bd and chemical properties (total organic carbon - COT, total nitrogen - N, exchangeable calcium - Ca2+, and pH. The results indicated that more intense soil preparation (M < NT < PC resulted in a decrease in soil stability, confirmed by all stability indicators analyzed: MWD, MGD, ASI, aggregate class distribution, WDC and FI, indicating the validity of these indicators in aggregation analyses of the studied soil.

  19. Corrosion of amalgams under sliding wear. (United States)

    Lian, K; Meletis, E I


    During mastication, dental amalgams are simultaneously subjected to corrosion by the oral environment and to a sliding-wear process by biting forces. In the present study, the effect of sliding wear on the corrosion behavior of two high-copper dental amalgams was investigated. An experimental apparatus was utilized that allows electrochemical testing under sliding-wear conditions. Corrosion potential measurements and anodic polarization scans were conducted in 0.1 M NaCl solution under sliding wear to characterize the behavior of two commercial, high-copper, single composition dental amalgams. In addition, long duration tests were conducted to assess possible corrosion and wear synergistic effects. The results showed that sliding wear caused a sharp reduction in the corrosion potential, a significant increase in the corrosion rate and a decrease in the repassivation rate of both amalgams. These effects are due to the mechanical removal by the wear process of the surface protective film formed on dental amalgams. The simultaneous action of sliding wear and corrosion can also induce embrittlement that leads to cracking. The present evidence suggests that this cracking may be one of the major contributors to marginal failures of dental amalgam restorations.

  20. High-Speed Interferometry Under Impacting Drops

    KAUST Repository

    Langley, Kenneth R.


    Over the last decade the rapid advances in high-speed video technology, have opened up to study many multi-phase fluid phenomena, which tend to occur most rapidly on the smallest length-scales. One of these is the entrapment of a small bubble under a drop impacting onto a solid surface. Here we have gone from simply observing the presence of the bubble to detailed imaging of the formation of a lubricating air-disc under the drop center and its subsequent contraction into the bubble. Imaging the full shape-evolution of the air-disc has required μm and sub-μs space and time resolutions. Time-resolved 200 ns interferometry with monochromatic light, has allowed us to follow individual fringes to obtain absolute air-layer thicknesses, based on the eventual contact with the solid. We can follow the evolution of the dimple shape as well as the compression of the gas. The improved imaging has also revealed new levels of detail, like the nature of the first contact which produces a ring of micro-bubbles, highlighting the influence of nanometric surface roughness. Finally, for impacts of ultra-viscous drops we see gliding on ~100 nm thick rarified gas layers, followed by extreme wetting at numerous random spots.

  1. Highly stable superhydrophobic surfaces under flow conditions (United States)

    Lee, Moonchan; Yim, Changyong; Jeon, Sangmin


    We synthesized hydrophobic anodic aluminum oxide nanostructures with pore diameters of 35, 50, 65, and 80 nm directly on quartz crystal microresonators, and the stability of the resulting superhydrophobicity was investigated under flow conditions by measuring changes in the resonance frequency and dissipation factor. When the quartz substrates were immersed in water, their hydrophobic surfaces did not wet due to the presence of an air interlayer. The air interlayer was gradually replaced by water over time, which caused decreases in the resonance frequency (i.e., increases in mass) and increases in the dissipation factor (i.e., increases in viscous damping). Although the water contact angles of the nanostructures increased with increasing pore size, the stability of their superhydrophobicity increased with decreasing pore size under both static conditions (without flow) and dynamic conditions (with flow); this increase can be attributed to an increase in the solid surface area that interacts with the air layer above the nanopores as the pore size decreases. Further, the effects of increasing the flow rate on the stability of the superhydrophobicity were quantitatively determined.

  2. Nanoscale Morphology Evolution Under Ion Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, Michael J. [President & Fellows of Harvard College, Cambridge, MA (United States)


    We showed that the half-century-old paradigm of morphological instability under irradiation due to the curvature-dependence of the sputter yield, can account neither for the phase diagram nor the amplification or decay rates that we measure in the simplest possible experimental system -- an elemental semiconductor with an amorphous surface under noble-gas ion irradiation; We showed that a model of pattern formation based on the impact-induced redistribution of atoms that do not get sputtered away explains our experimental observations; We developed a first-principles, parameter-free approach for predicting morphology evolution, starting with molecular dynamics simulations of single ion impacts, lasting picoseconds, and upscaling through a rigorous crater-function formalism to develop a partial differential equation that predicts morphology evolution on time scales more than twelve orders of magnitude longer than can be covered by the molecular dynamics; We performed the first quantitative comparison of the contributions to morphological instability from sputter removal and from impact-induced redistribution of atoms that are removed, and showed that the former is negligible compared to the latter; We established a new paradigm for impact-induced morphology evolution based on crater functions that incorporate both redistribution and sputter effects; and We developed a model of nanopore closure by irradiation-induced stress and irradiationenhanced fluidity, for the near-surface irradiation regime in which nuclear stopping predominates, and showed that it explains many aspects of pore closure kinetics that we measure experimentally.

  3. Accelerated reliability demonstration under competing failure modes

    International Nuclear Information System (INIS)

    Luo, Wei; Zhang, Chun-hua; Chen, Xun; Tan, Yuan-yuan


    The conventional reliability demonstration tests are difficult to apply to products with competing failure modes due to the complexity of the lifetime models. This paper develops a testing methodology based on the reliability target allocation for reliability demonstration under competing failure modes at accelerated conditions. The specified reliability at mission time and the risk caused by sampling of the reliability target for products are allocated for each failure mode. The risk caused by degradation measurement fitting of the target for a product involving performance degradation is equally allocated to each degradation failure mode. According to the allocated targets, the accelerated life reliability demonstration test (ALRDT) plans for the failure modes are designed. The accelerated degradation reliability demonstration test plans and the associated ALRDT plans for the degradation failure modes are also designed. Next, the test plan and the decision rules for the products are designed. Additionally, the effects of the discreteness of sample size and accepted number of failures for failure modes on the actual risks caused by sampling for the products are investigated. - Highlights: • Accelerated reliability demonstration under competing failure modes is studied. • The method is based on the reliability target allocation involving the risks. • The test plan for the products is based on the plans for all the failure modes. • Both failure mode and degradation failure modes are considered. • The error of actual risks caused by sampling for the products is small enough

  4. Improvement of Statistical Decisions under Parametric Uncertainty (United States)

    Nechval, Nicholas A.; Nechval, Konstantin N.; Purgailis, Maris; Berzins, Gundars; Rozevskis, Uldis


    A large number of problems in production planning and scheduling, location, transportation, finance, and engineering design require that decisions be made in the presence of uncertainty. Decision-making under uncertainty is a central problem in statistical inference, and has been formally studied in virtually all approaches to inference. The aim of the present paper is to show how the invariant embedding technique, the idea of which belongs to the authors, may be employed in the particular case of finding the improved statistical decisions under parametric uncertainty. This technique represents a simple and computationally attractive statistical method based on the constructive use of the invariance principle in mathematical statistics. Unlike the Bayesian approach, an invariant embedding technique is independent of the choice of priors. It allows one to eliminate unknown parameters from the problem and to find the best invariant decision rule, which has smaller risk than any of the well-known decision rules. To illustrate the proposed technique, application examples are given.

  5. Biological degradation of chernozems under irrigation

    Directory of Open Access Journals (Sweden)

    Oksana Naydyonova


    Full Text Available We studied the changes in the state of microbial cenosis of Ukraine’s chernozems under irrigation. Considerable part of Ukraine’s chernozems is located in the areas where humidification is insufficient and unstable. Irrigation is a soil-reclamation measure for chernozems of Ukrainian Forest-steppe and Steppe which enables getting the assured yield, especially vegetable and fodder crops. At the same time, irrigation is a powerful anthropogenic factor that affects the soil, causes a significant transformation of many of its properties and regimes including biological ones. Often these changes are negative. The purpose of our investigation was to identify changes in the state of microbial cenoses of chernozem soils under irrigation which depend on such factors as the quality of irrigation water, the duration and intensity of irrigation, the initial properties of soil, the structure of crop rotation, usage of fertilizing systems and agroameliorative techniques. We identified direction and evaluated a degree of changes in biological properties of chernozems under influence of irrigation in different agro-irrigational and soil-climatic conditions. In the long-term stationary field experiments we identified the following biological indices of irrigated soils and their non-irrigated analogues: a number of microorganisms which belong to main ecological-trophic groups, activity of soil enzymes (dehydrogenase, invertase, phenol oxidase, soil phytotoxic activity, cellulose destroying capacity of soil, indices of oligotrophy and mineralization, summary biological index (SBI and index of biological degradation (BDI. Results of researches showed that irrigation unbalanced the soil ecosystem and stipulated the forming of microbial cenosis with new parameters. Long-term intensive irrigation of typical chernozem (Kharkiv Region with fresh water under condition of 4-fields vegetable crop rotation led to the degradation changes of its microbial cenosis such as

  6. Nitrogen mineralization in soils under grasses and under trees in a protected Venezuelan savanna (United States)

    Sánchez, L. F.; García-Miragaya, J.; Chacón, N.

    Nitrogen mineralization was evaluated in soils beneath the most common woody species growing isolated within the grass matrix of a Venezuelan Trachypogon savanna, which has been protected from fire and cattle grazing since 1961. Adult trees of three evergreen species, Byrsonima crassifolia (L) H. B. K., Curatella americana L., and Bowdichia virgilioides H. B. K; and two deciduous, Godmania macrocarpa Hemsley and Cochlospermun vitifolium (Wild) Spreng were selected. The amount of N mineralized (NH 4+-N+NO 3--N) during 15 weeks of laboratory incubation of soils collected from beneath trees, was significantly higher ( p<0.01) than those from under grasses. Values of N mineralized on soil from under trees were from 21.28 to 82.65% greater than for soil from under grasses. A highly significant ( p<0.01) positive correlation, for all soils, was found between Nm and SOC, and between Nm and Nt. The higher N mineralization rates under trees would reflect a higher soil biological activity, due to higher SOC and Nt, of the soils under the tree canopies than those under grasses. The N availability values obtained under all species reveal the importance these trees have for creating enriched areas on generally oligotrophic soils. Nitrogen mineralized in the soil from beneath evergreen trees was significantly ( p<0.01) higher than from under deciduous trees, being 25.87% higher on average. Similarly to the relation found for all soils, a highly significant ( p<0.01) positive correlation between Nm and SOC and between Nm and Nt was also obtained for soils beneath all trees, indicating the importance of SOC and Nt for nitrogen mineralization processes in this savanna. The higher SOC and Nt contents found under evergreen trees are probably due to the longer time they have been established on the site as compared to the deciduous ones. The chemical quality of fresh fallen leaves (as measured by their lignin/nitrogen ratio) did not seem to influence the quality of the SOM (as

  7. Microbial Fuel Cells under Extreme Salinity (United States)

    Monzon del Olmo, Oihane

    I developed a Microbial Fuel Cell (MFC) that unprecedentedly works (i.e., produces electricity) under extreme salinity (≈ 100 g/L NaCl). Many industries, such as oil and gas extraction, generate hypersaline wastewaters with high organic strength, accounting for about 5% of worldwide generated effluents, which represent a major challenge for pollution control and resource recovery. This study assesses the potential for microbial fuel cells (MFCs) to treat such wastewaters and generate electricity under extreme saline conditions. Specifically, the focus is on the feasibility to treat hypersaline wastewater generated by the emerging unconventional oil and gas industry (hydraulic fracturing) and so, with mean salinity of 100 g/L NaCl (3-fold higher than sea water). The success of this novel technology strongly depends on finding a competent and resilient microbial community that can degrade the waste under extreme saline conditions and be able to use the anode as their terminal electron acceptor (exoelectrogenic capability). I demonstrated that MFCs can produce electricity at extremely high salinity (up to 250 g/l NaCl) with a power production of 71mW/m2. Pyrosequencing analysis of the anode population showed the predominance of Halanaerobium spp. (85%), which has been found in shale formations and oil reservoirs. Promoting Quorum sensing (QS, cell to cell communication between bacteria to control gene expression) was used as strategy to increase the attachment of bacteria to the anode and thus improve the MFC performance. Results show that the power output can be bolstered by adding 100nM of quinolone signal with an increase in power density of 30%, for the first time showing QS in Halanaerobium extremophiles. To make this technology closer to market applications, experiments with real wastewaters were also carried out. A sample of produced wastewater from Barnet Shale, Texas (86 g/L NaCl) produced electricity when fed in an MFC, leading to my discovery of another

  8. Conservation policies and planning under climate change

    DEFF Research Database (Denmark)

    Strange, Niels; Thorsen, Bo Jellesmark; Bladt, Jesper Stentoft


    Biodiversity conservation policies focus on securing the survival of species and habitats according to their current distribution. This basic premise may be inappropriate for halting biodiversity decline under the dynamic changes caused by climate change. This study explores a dynamic spatial...... conservation prioritization problem where climate change gradually changes the future habitat suitability of a site’ current species. This has implications for survival probability, as well as for species that potentially immigrate to the site. The problem is explored using a set of heuristics for both of two...... networks. Climate change induced shifts in the suitability of habitats for species may increase the value of such adaptive strategies, the benefit decreasing with increasing migration probabilities and species distribution dynamics....

  9. Superconductivity from magnetic elements under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Katsuya [KYOKUGEN, Research Center for Materials Science at Extreme Conditions, Osaka University, Osaka 560-8531 (Japan)]. E-mail:; Amaya, Kiichi [Toyota Physical and Chemical Research Institute, Aichi 480-1192 (Japan); Suzuki, Naoshi [Graduate School of Engineering Science, Osaka University, Osaka 560-8531 (Japan); Onuki, Yoshichika [Graduate School of Science, Osaka University, Osaka 560-0043 (Japan)


    Can we expect the appearance of superconductivity from magnetic elements? In general, superconductivity occurs in nonmagnetic metal at low temperature and magnetic impurities destroy superconductivity; magnetism and superconductivity are as incompatible as oil and water. Here, we present our experimental example of superconducting elements, iron and oxygen. They are magnetic at ambient pressure, however, they become nonmagnetic under high pressure, then superconductor at low temperature. What is the driving force of the superconductivity? Our understanding in the early stages was a simple scenario that the superconductive state was obtained as a consequence of an emergence of the nonmagnetic states. In both cases, we may consider another scenario for the appearance of superconductivity; the magnetic fluctuation mechanism in the same way as unconventional superconductors.

  10. The Genetic and Environmental Factors Underlying Hypospadias (United States)

    Pask, Andrew; Heloury, Yves; Sinclair, Andrew H.


    Hypospadias results from a failure of urethral closure in the male phallus and affects 1 in 200–300 boys. It is thought to be due to a combination of genetic and environmental factors. The development of the penis progresses in 2 stages: an initial hormone-independent phase and a secondary hormone-dependent phase. Here, we review the molecular pathways that contribute to each of these stages, drawing on studies from both human and mouse models. Hypospadias can occur when normal development of the phallus is disrupted, and we provide evidence that mutations in genes underlying this developmental process are causative. Finally, we discuss the environmental factors that may contribute to hypospadias and their potential immediate and transgen erational epigenetic impacts. PMID:26613581

  11. Behavior of disordered boron carbide under stress. (United States)

    Fanchini, Giovanni; McCauley, James W; Chhowalla, Manish


    Gibbs free-energy calculations based on density functional theory have been used to determine the possible source of failure of boron carbide just above the Hugoniot elastic limit (HEL). A range of B4C polytypes is found to be stable at room pressure. The energetic barrier for shock amorphization of boron carbide is by far the lowest for the B12(CCC) polytype, requiring only 6 GPa approximately = P(HEL) for collapse under hydrostatic conditions. The results clearly demonstrate that the collapse of the B12(CCC) phase leads to segregation of B12 and amorphous carbon in the form of 2-3 nm bands along the (113) lattice direction, in excellent agreement with recent transmission electron microscopy results.

  12. Optimal Portfolio Selection Under Concave Price Impact

    International Nuclear Information System (INIS)

    Ma Jin; Song Qingshuo; Xu Jing; Zhang Jianfeng


    In this paper we study an optimal portfolio selection problem under instantaneous price impact. Based on some empirical analysis in the literature, we model such impact as a concave function of the trading size when the trading size is small. The price impact can be thought of as either a liquidity cost or a transaction cost, but the concavity nature of the cost leads to some fundamental difference from those in the existing literature. We show that the problem can be reduced to an impulse control problem, but without fixed cost, and that the value function is a viscosity solution to a special type of Quasi-Variational Inequality (QVI). We also prove directly (without using the solution to the QVI) that the optimal strategy exists and more importantly, despite the absence of a fixed cost, it is still in a “piecewise constant” form, reflecting a more practical perspective.

  13. Why do objects appear enlarged under water?

    Directory of Open Access Journals (Sweden)

    Helen E. Ross


    Full Text Available Objects appear enlarged in water by less than the 4/3 angular magnification. They usually appear beyond their optical distance and slightly enlarged in linear size, but not in accordance with size-distance invariance (SDI. We investigated whether misperceptions of angular size could explain the discrepancies. Twenty observers viewed targets of various sizes and distances within transparent tanks 40 cm long containing air or water. They judged distance by hidden reaching, and linear or angular size by adjusting the size of a target in air at a further distance. Matched distance was close to physical distance in air and optical distance in water. All size matches were close to true linear size, and were larger in water than in air. Angular size matches were much too small to explain departures from SDI. Size perception under water is best explained by incomplete adaptation to optical distortion, and by the use of various size cues.

  14. Supporting chemical process design under uncertainty

    Directory of Open Access Journals (Sweden)

    A. Wechsung


    Full Text Available A major challenge in chemical process design is to make design decisions based on partly incomplete or imperfect design input data. Still, process engineers are expected to design safe, dependable and cost-efficient processes under these conditions. The complexity of typical process models limits intuitive engineering estimates to judge the impact of uncertain parameters on the proposed design. In this work, an approach to quantify the effect of uncertainty on a process design in order to enhance comparisons among different designs is presented. To facilitate automation, a novel relaxation-based heuristic to differentiate between numerical and physical infeasibility when simulations do not converge is introduced. It is shown how this methodology yields more details about limitations of a studied process design.

  15. Diffraction studies of water under pressure

    International Nuclear Information System (INIS)

    Neilson, G.W.


    During the past decade, improvements in experimental techniques and computer simulation methods have led to a more comprehensive understanding of the properties of water. Foremost among these are X-ray and neutron diffraction which provide information directly of the microscopic structure. Water can exist over a wide range of pressure and temperature and many of its properties change in a characteristic way. It is, therefore, worthwhile to see what microscopic changes occur in the liquid as P and T are systematically varied. Recent developments in diffraction studies on water under pressure are reviewed, paying particular attention to pressure cell construction and structural changes and how these compare with results obtained from other methods

  16. Phototaxis of Cyanobacteria under Complex Light Environments

    Directory of Open Access Journals (Sweden)

    Minsu Kim


    Full Text Available Photosynthetic bacteria are capable of producing their own food via photosynthesis. Unsurprisingly, they evolved the ability to move toward better light conditions (i.e., phototaxis. In a recent article in mBio, Chau et al. tuned the wavelength, flux, direction, and timing of light input and characterized the motility of the unicellular cyanobacterium Synechocystis sp. strain PCC6803 (R. M. W. Chau, D. Bhaya, and K. C. Huang, mBio 8:e02330-16, 2017, The results revealed an intricate dependence of the motility on various light inputs, laying the fundamental groundwork toward understanding phototaxis under complex and dynamic light environments.

  17. Evolved Mechanisms Versus Underlying Conditional Relations

    Directory of Open Access Journals (Sweden)

    Astorga Miguel López


    Full Text Available The social contracts theory claims that, in social exchange circumstances, human reasoning is not necessarily led by logic, but by certain evolved mental mechanisms that are useful for catching offenders. An emblematic experiment carried out with the intention to prove this thesis is the first experiment described by Fiddick, Cosmides, and Tooby in their paper of 2000. Lopez Astorga has questioned that experiment claiming that its results depend on an underlying conditional logical form not taken into account by Fiddick, Cosmides, and Tooby. In this paper, I propose an explanation alternative to that of Lopez Astorga, which does not depend on logical forms and is based on the mental models theory. Thus, I conclude that this other alternative explanation is one more proof that the experiment in question does not demonstrate the fundamental thesis of the social contracts theory.

  18. Diffusion of irreversible energy technologies under uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Cacallo, J.D.; Sutherland, R.J.


    This paper presents a model of technology diffusion is consistent with characteristics of participants in most energy markets. Whereas the models used most widely for empirical research are based on the assumption that the extended delays in adoption of cost-saving innovations are the result of either lack of knowledge about the new processes or heterogeneity across potential adopters, the model presented in this paper is based on the strategic behavior by firms. The strategic interdependence of the firms` decisions is rooted in spillover effects associated with an inability to exclude others from the learning-by-doing acquired when a firm implements a new technology. The model makes extensive use of recent developments in investment theory as it relates irreversible investments under uncertainty.

  19. Magnetoelastic Demagnetization of Steel under Cyclic Loading (United States)

    Muratov, K. R.; Novikov, V. F.; Neradovskii, D. F.; Kazakov, R. Kh.


    Magnetoelastic demagnetization of steel samples under cyclic tensile loads has been analyzed. It has been established that values of residual magnetization that correspond to peak loads are characterized by the power-law dependence on the number of loading cycles. In some cases, in the region of high loads, the qualitative transition to exponential dependence has been observed. Coefficients of the power-law approximation of peak magnetization depend on the value of amplitude load and have specific characteristics in the vicinity of characteristic loads. The ratios of approximated slide load coefficients depending on the load are common for the three considered samples, and there is an outburst in the vicinity of the fatigue limit, which can be used as the basis for developing the rapid nondestructive method for determination of this limit.

  20. Aerial view of CERN under the snow

    CERN Multimedia

    CERN PhotoLab


    In this photograph taken in the winter of 1963, CERN still looks quite bare under its mantle of snow. The Proton Synchrotron (PS), resembling a bicycle wheel in shape, had been in operation since the summer of 1959. A proposal had just been made for the site of CERN's second large project, the Intersecting Storage Rings (ISR): France was to house the world's first proton-proton collider. In September 1965, the French authorities signed an agreement making more than 40 hectares of land available for the extension of the CERN site established in Switzerland into French territory. The ISR project received final approval from the CERN Council in December 1965. The civil engineering work on the French part began in November 196

  1. Flows in networks under fuzzy conditions

    CERN Document Server

    Bozhenyuk, Alexander Vitalievich; Kacprzyk, Janusz; Rozenberg, Igor Naymovich


    This book offers a comprehensive introduction to fuzzy methods for solving flow tasks in both transportation and networks. It analyzes the problems of minimum cost and maximum flow finding with fuzzy nonzero lower flow bounds, and describes solutions to minimum cost flow finding in a network with fuzzy arc capacities and transmission costs. After a concise introduction to flow theory and tasks, the book analyzes two important problems. The first is related to determining the maximum volume for cargo transportation in the presence of uncertain network parameters, such as environmental changes, measurement errors and repair work on the roads. These parameters are represented here as fuzzy triangular, trapezoidal numbers and intervals. The second problem concerns static and dynamic flow finding in networks under fuzzy conditions, and an effective method that takes into account the network’s transit parameters is presented here. All in all, the book provides readers with a practical reference guide to state-of-...

  2. Fuel corrosion processes under waste disposal conditions

    International Nuclear Information System (INIS)

    Shoesmith, D.W.


    Under the oxidizing conditions likely to be encountered in the Yucca Mountain Repository, fuel dissolution is a corrosion process involving the coupling of the anodic dissolution of the fuel with the cathodic reduction of oxidants available within the repository. The oxidants potentially available to drive fuel corrosion are environmental oxygen, supplied by the transport through the permeable rock of the mountain and molecular and radical species produced by the radiolysis of available aerated water. The mechanism of these coupled anodic and cathodic reactions is reviewed in detail. While gaps in understanding remain, many kinetic features of these reactions have been studied in considerable detail, and a reasonably justified mechanism for fuel corrosion is available. The corrosion rate is determined primarily by environmental factors rather than the properties of the fuel. Thus, with the exception of increase in rate due to an increase in surface area, pre-oxidation of the fuel has little effect on the corrosion rate

  3. Sectioning of radiolarians under continuous observation

    Directory of Open Access Journals (Sweden)

    J. Stanek


    Full Text Available A new method to study the internal structure of fossil radiolarians in presented. The core of the method is (1 freezing the radiolarian in a drop of water using a Peltier module and (2 slicing the radiolarian with a specially equipped electric tooth-brush under an optical microscope. With this method the internal structure of diagenetically altered radiolarians can be studied even if internal sediment cannot be removed. Eine neue Methode zur Analyse der Internstrukturen von Radiolarien wird vorgestellt. Die Methode beinhaltet (1 Einfrieren einzelner Radiolarien in einem Wassertropfen mit Hilfe eine Peltier-Elements und (2 Schleifen der Radiolarien mit Hilfe eine modifizierten elektrischen Zahnbürste unter einem Binokular. Mit dieser Methode ist es möglich Internstrukturen von Radiolarien zu untersuchen, selbst wenn diese diagenetisch verändert sind oder fest verbackenes Internsediment aufweisen. doi:10.1002/mmng.20020050104

  4. The Danish free school tradition under pressure

    DEFF Research Database (Denmark)

    Olsen, Tore Vincents


    The Danish free school tradition has entailed a large degree of associational freedom for non-governmental schools, religious as well as non-religious. Until the late 1990s, the non-governmental schools were under no strict ideological or pedagogical limitations, they could recruit teachers...... and students according to their own value base, and were given a large state subsidy. From the late 1990s a number of legislative changes were introduced demanding that non-governmental schools provide civic education and document the academic value of their teaching programs. The rules concerning...... the monitoring of schools were also changed. This article analyses the political justification for these changes and asks to what extent the changes have altered the Danish free school tradition....

  5. Chloride Ingress into Concrete under Water Pressure

    DEFF Research Database (Denmark)

    Lund, Mia Schou; Sander, Lotte Braad; Grelk, Bent


    The chloride ingress into concrete under water pressures of 100 kPa and 800 kPa have been investigated by experiments. The specimens were exposed to a 10% NaCl solution and water mixture. For the concrete having w/c = 0.35 the experimental results show the chloride diffusion coefficient at 800 k......Pa (~8 atm.) is 12 times greater than at 100 kPa (~1 atm.). For w/c = 0.45 and w/c = 0.55 the chloride diffusion coefficients are 7 and 3 times greater. This means that a change in pressure highly influences the chloride ingress into the concrete and thereby the life length models for concrete structures....

  6. Oligoquinolines under Solvent-free Microwave Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kwi-Jeon; Kwon, Tae-Woo [Kyungsung University, Busan (Korea, Republic of)


    Quinolines are thermally stable and can be used as an excellent n-type semiconducting materials. Since quinolines are also known to be electron acceptor molecules, combination of various electron donor building blocks can be utilized in photonic and electronic organic light-emitting diode (OLED) applications. For example, donor.acceptor systems with phenothiazine (or carbazole) molecules as electron donors and the phenylquinoline group as an electron acceptor provide an efficient approach for the design of new materials exhibiting highly efficient charge-transfer photophysics and electroluminescence in OLEDs. We have described the Friedlander quinoline synthesis between aminobenzophenones and symmetrical diacetyl compounds having phenothiazine, carbazole, biphenyl, and phenyl moieties under solvent-free microwave irradiation in 12.98% isolated yields.

  7. [Newborn children under phototherapy: the mother's perception]. (United States)

    Campos, Antonia do Carmo Soares; Cardoso, Maria Vera Lúcia Moreira Leitão


    Since 1958, phototherapy has been used as a method to cure jaundice, which is still an important disease in newborn children. Supported by a phenomenological and qualitative approach, this study aims to investigate the mothers' perception of the phototherapy treatment their children are submitted to. Research subjects were ten mothers of newborns under phototherapy treatment at the Neonatological Hospitalization Unit of a public maternity in Fortaleza-CE, Brazil. Data were collected between May and July 2002. We used group meetings with the mothers as suggested by Carl Rogers. Discourse was organized into categories according to Bardin, which revealed themes that were analyzed in view of Paterson's and Zderad's humanistic nursing theory, as follows: mothers' knowledge on phototherapy and concerns about the treatment. We concluded that the analyzed mothers' major concern is related to the babies' vision.

  8. Ocean commitments under the Paris Agreement (United States)

    Gallo, Natalya D.; Victor, David G.; Levin, Lisa A.


    Under the Paris Agreement nations made pledges known as nationally determined contributions (NDCs), which indicate how national governments are evaluating climate risks and policy opportunities. We find that NDCs reveal important systematic patterns reflecting national interests and capabilities. Because the ocean plays critical roles in climate mitigation and adaptation, we created a quantitative marine focus factor (MFF) to evaluate how governments address marine issues. In contrast to the past, when oceans received minimal attention in climate negotiations, 70% of 161 NDCs we analysed include marine issues. The percentage of the population living in low-lying areas--vulnerable to rising seas--positively influences the MFF, but negotiating group (Annex 1 or small island developing states) is equally important, suggesting political motivations are crucial to NDC development. The analysis reveals gaps between scientific and government attention, including on ocean deoxygenation, which is barely mentioned. Governments display a keen interest in expanding marine research on climate priorities.

  9. Thermomechanics of composite structures under high temperatures

    CERN Document Server

    Dimitrienko, Yu I


    This pioneering book presents new models for the thermomechanical behavior of composite materials and structures taking into account internal physico-chemical transformations such as thermodecomposition, sublimation and melting at high temperatures (up to 3000 K). It is of great importance for the design of new thermostable materials and for the investigation of reliability and fire safety of composite structures. It also supports the investigation of interaction of composites with laser irradiation and the design of heat-shield systems. Structural methods are presented for calculating the effective mechanical and thermal properties of matrices, fibres and unidirectional, reinforced by dispersed particles and textile composites, in terms of properties of their constituent phases. Useful calculation methods are developed for characteristics such as the rate of thermomechanical erosion of composites under high-speed flow and the heat deformation of composites with account of chemical shrinkage. The author expan...

  10. Gravitational time advancement under gravity's rainbow

    Directory of Open Access Journals (Sweden)

    Xue-Mei Deng


    Full Text Available Under gravity's rainbow, we investigate its effects on the gravitational time advancement, which is a natural consequence of measuring proper time span for a photon's round trip. This time advancement can be complementary to the time delay for testing the gravity's rainbow, because they are sensitive to different modified dispersion relations (MDRs. Its observability on ranging a spacecraft far from the Earth by two radio and a laser links is estimated at superior conjunction (SC and inferior conjunction (IC. We find that (1 the IC is more favorable than the SC for measurement on the advancement caused by the rainbow; (2 a specific type of MDR has a significantly larger effect on the advancement than others in both SC and IC cases; and (3 a combination of available optical clocks and the realization of planetary laser ranging in the future will benefit distinguishing the gravity's rainbow from GR by measuring the gravitational time advancement.

  11. Medical tourism analysis under the innovation perspective

    Directory of Open Access Journals (Sweden)

    Keline Leão Ferreira


    Full Text Available Medical tourism, although being considered a recent phenomenon in Brazil, still represents an important opportunity for institutions that have health facilities, human resources and advanced technological level. This work aims to develop a reflection about this market based under the innovation theoretical perspectives. In order to support this analysis was conducted a multi case study in four health institutions located in the Brazilian south region. Results confirmed that these institutions developed innovations, classified as innovation in product, process, organizational and marketing. Moreover, the evidences indicated that the institution participation on medical tourism market, using innovation as a competitive advantage, helps to promote a new business design and organizational processes, adequate infrastructure, assigning a due importance to the marketing and management sectors, generating an external recognition, a larger network relationships, cooperation among peers, ensuring to these institutions an international standard of service delivery.

  12. Molecular Signatures Underlying Synaptic Vesicle Cargo Retrieval (United States)

    Mori, Yasunori; Takamori, Shigeo


    Efficient retrieval of the synaptic vesicle (SV) membrane from the presynaptic plasma membrane, a process called endocytosis, is crucial for the fidelity of neurotransmission, particularly during sustained neural activity. Although multiple modes of endocytosis have been identified, it is clear that the efficient retrieval of the major SV cargos into newly formed SVs during any of these modes is fundamental for synaptic transmission. It is currently believed that SVs are eventually reformed via a clathrin-dependent pathway. Various adaptor proteins recognize SV cargos and link them to clathrin, ensuring the efficient retrieval of the cargos into newly formed SVs. Here, we summarize our current knowledge of the molecular signatures within individual SV cargos that underlie efficient retrieval into SV membranes, as well as discuss possible contributions of the mechanisms under physiological conditions. PMID:29379416

  13. Burnout characteristics under flow reduction condition

    International Nuclear Information System (INIS)

    Iwamura, Takamichi; Kuroyanagai, Toshiyuki


    Burnout characteristics in a uniformly heated, vertically oriented tube, under flow reduction condition, were experimentally studied. Test pressures ranged 0.5 -- 3.9 MPa and flow reduction rates 0.6 -- 35%/s. An analytical method was developed to obtain the local mass velocity during a transient condition. The local mass velocity at the burnout location with an increasing flow reduction rate was slightly different from that measured in steady state tests. The system pressure had a significant effect on the difference. An empirical correlation was presented to give the ratio between the transient and steady state burnout mass velocities at the burnout location as a function of the steam-water density ratio and the flow reduction rate. Experimental results of previous work were compared with this correlation. (author)

  14. Compound Option Pricing under Fuzzy Environment

    Directory of Open Access Journals (Sweden)

    Xiandong Wang


    Full Text Available Considering the uncertainty of a financial market includes two aspects: risk and vagueness; in this paper, fuzzy sets theory is applied to model the imprecise input parameters (interest rate and volatility. We present the fuzzy price of compound option by fuzzing the interest and volatility in Geske’s compound option pricing formula. For each α, the α-level set of fuzzy prices is obtained according to the fuzzy arithmetics and the definition of fuzzy-valued function. We apply a defuzzification method based on crisp possibilistic mean values of the fuzzy interest rate and fuzzy volatility to obtain the crisp possibilistic mean value of compound option price. Finally, we present a numerical analysis to illustrate the compound option pricing under fuzzy environment.

  15. CQ Switch Analysis under Traffic Overload

    Directory of Open Access Journals (Sweden)

    I. Maljević


    Full Text Available An analysis of 2x2 crossbar packet switch with buffers at crosspoints and round robin scheduling algorithm is presented in this paper. The analysis is performed for a non-admissible traffic pattern, where output ports are overloaded. The case of full offered load is observed and output ports are loaded with packets that have different arrival probabilities. In addition to the parameters that are commonly observed in such an analysis (throughput and average packet delay, memory requirements for the implementation of the buffer, as well as fair representation when servicing the buffer - the so-called fairness are also analyzed. The results show that even for a switch with a small number of ports very large buffers should be implemented, if we want to achieve satisfactory performance under traffic overload.

  16. Conservation policies and planning under climate change

    DEFF Research Database (Denmark)

    Strange, Niels; Thorsen, Bo Jellesmark; Bladt, Jesper Stentoft


    conservation prioritization problem where climate change gradually changes the future habitat suitability of a site’ current species. This has implications for survival probability, as well as for species that potentially immigrate to the site. The problem is explored using a set of heuristics for both of two...... networks. Climate change induced shifts in the suitability of habitats for species may increase the value of such adaptive strategies, the benefit decreasing with increasing migration probabilities and species distribution dynamics.......Biodiversity conservation policies focus on securing the survival of species and habitats according to their current distribution. This basic premise may be inappropriate for halting biodiversity decline under the dynamic changes caused by climate change. This study explores a dynamic spatial...

  17. Does filial piety exist under Chinese communism? (United States)

    Chow, N


    China has been known for centuries for its traditions of respecting the old. While this tradition has been weakened in the modern era, it still remains as the most important value underlying the practice of supporting the old in present-day China. This article looks into the meaning of filial piety, or xiao, and examines how it has been observed both in the old and modern times. It argues that though the Chinese communists have found filial piety ideologically repulsive, they have nevertheless tolerated it and even used it as the basis for a welfare network to support the elderly in the villages. However, in order to be truthful to their socialist ideology, they have also provided for urban workers the most sophisticated state-financed retirement benefits. Two different kinds of systems to support the elderly hence exist in China. The tensions resulting from this dichotomous situation are examined.

  18. Fiber Bundle Model Under Heterogeneous Loading (United States)

    Roy, Subhadeep; Goswami, Sanchari


    The present work deals with the behavior of fiber bundle model under heterogeneous loading condition. The model is explored both in the mean-field limit as well as with local stress concentration. In the mean field limit, the failure abruptness decreases with increasing order k of heterogeneous loading. In this limit, a brittle to quasi-brittle transition is observed at a particular strength of disorder which changes with k. On the other hand, the model is hardly affected by such heterogeneity in the limit where local stress concentration plays a crucial role. The continuous limit of the heterogeneous loading is also studied and discussed in this paper. Some of the important results related to fiber bundle model are reviewed and their responses to our new scheme of heterogeneous loading are studied in details. Our findings are universal with respect to the nature of the threshold distribution adopted to assign strength to an individual fiber.

  19. Contrast edge colors under different natural illuminations. (United States)

    Nieves, Juan Luis; Nascimento, Sérgio M C; Romero, Javier


    Essential to sensory processing in the human visual system is natural illumination, which can vary considerably not only across space but also along the day depending on the atmospheric conditions and the sun's position in the sky. In this work, edges derived from the three postreceptoral Luminance, Red-Green, and Blue-Yellow signals were computed from hyperspectral images of natural scenes rendered with daylights of Correlated Color Temperatures (CCTs) from 2735 to 25,889 K; for low CCT, the same analysis was performed using Planckian illuminants up to 800 K. It was found that average luminance and chromatic edge contrasts were maximal for low correlated color temperatures and almost constants above 10,000 K. The magnitude of these contrast changes was, however, only about 2% across the tested daylights. Results suggest that the postreceptoral opponent and nonopponent color vision mechanisms produce almost constant responses for color edge detection under natural illumination. © 2012 Optical Society of America

  20. Managing Carbon Footprints under the Trade Credit

    Directory of Open Access Journals (Sweden)

    Xiaohong Chen


    Full Text Available We investigate how the retailer adjusts optimal ordering policy in the presence of cap-and-trade system and trade credit, and the corresponding changes of the retailer’s total costs and carbon footprint. Trade credit is one of the most used short-term financing tools. Our study shows that carbon emissions trading will shorten the ordering cycle for products that emit more carbon dioxide during the storage stage, and therefore reduce the buying behavior stimulation effect of trade credit on these products. Under the cap-and-trade system, the retailer’s total cost may increase or decrease, depending on the combination of carbon cap allocated to the retailer and the carbon price. Moreover, trade credit and the corresponding cost of capital affect the retailer’s carbon emission reduction strategy by changing the retailers’ consolidated cost during the ordering and inventory holding stages.

  1. Stability under persistent perturbation by white noise

    International Nuclear Information System (INIS)

    Kalyakin, L


    Deterministic dynamical system which has an asymptotical stable equilibrium is considered under persistent perturbation by white noise. It is well known that if the perturbation does not vanish in the equilibrium position then there is not Lyapunov's stability. The trajectories of the perturbed system diverge from the equilibrium to arbitrarily large distances with probability 1 in finite time. New concept of stability on a large time interval is discussed. The length of interval agrees the reciprocal quantity of the perturbation parameter. The measure of stability is the expectation of the square distance from the trajectory till the equilibrium position. The method of parabolic equation is applied to both estimate the expectation and prove such stability. The main breakthrough is the barrier function derived for the parabolic equation. The barrier is constructed by using the Lyapunov function of the unperturbed system

  2. Analyzing Technique of Power Systems Under Deregulation (United States)

    Miyauchi, Hajime; Kita, Hiroyuki; Ishigame, Atsushi

    Deregulation of the electric utilities has been progressing. Even under the deregulation, the reliability should be the most important problem of power systems. However, according to the deregulation, operation and scheduling of power systems are changing and new techniques to analyze power systems are introducing. To evaluate reliability of power systems, adequacy and security are well employed recently. This paper presents the new analyzing technique which will be realized in near future from the viewpoint of adequacy and security. First, simulation tool to evaluate adequacy is described. As an example of this tool, MARS and other methods are mentioned. Next, to evaluate the security, security constrained unit commitment (SCUC) and security constrained optimal power flow (SCOPF) are mentioned. Finally, some topics concerning ancillary service are described.

  3. Green zoning regulation under price discrimination

    Directory of Open Access Journals (Sweden)

    Hamid Hamoudi


    Full Text Available This study aims to examine urban zoning within a linear city in a Bertrand duopolistic competition framework with price discrimination and linear transportation costs. It analyses the effects of introducing an environmental area where economic and residential activity are not allowed. The welfare function used to determine the optimal size of the green area allows for a possible regulator’s bias in favour of firms/consumers. It is shown that location-price competition can be either reduced or increased depending on the size of the green area. The results indicate when a regulator implements green zoning, under linear transportation costs, influences the optimal location of firms (because these locations depend on the size of the green zone. In consequence, zoning may be used as an effective industrial or urban policy tool.

  4. Phasor Measurement Unit under Interference Conditions

    DEFF Research Database (Denmark)

    Ghiga, Radu; Martin, Kenneth E.; Wu, Qiuwei


    This paper investigates the performance of Phasor Measurement Units (PMUs) under interference conditions which can appear in a power system and are not tested by the C37.118.1 standard. Three PMUs from different vendors configured for the M-class requirements were used to test three possible...... interference condition scenarios. In the first scenario, noise is added to the PMU input signal. The test runs a sweep of Signalto-Noise Ratios (SNR) and the accuracy versus the noise level is obtained. The second scenario injects multiple harmonics with the input to test the influence on accuracy. The last...... scenario focuses on instrument transformer saturation which leads to a modified waveform injected in the PMU. This test goes through different levels of Current Transformer (CT) saturation and analyzes the effect of saturation on the accuracy of PMUs. The test results show PMU measurements will be degraded...

  5. Modeling of porous concrete elements under load (United States)

    Demchyna, B. H.; Famuliak, Yu. Ye.; Demchyna, Kh. B.


    It is known that cell concretes are almost immediately destroyed under load, having reached certain critical stresses. Such kind of destruction is called a "catastrophic failure". Process of crack formation is one of the main factors, influencing process of concrete destruction. Modern theory of crack formation is mainly based on the Griffith theory of destruction. However, the mentioned theory does not completely correspond to the structure of cell concrete with its cell structure, because the theory is intended for a solid body. The article presents one of the possible variants of modelling of the structure of cell concrete and gives some assumptions concerning the process of crack formation in such hollow, not solid environment.

  6. Modeling of porous concrete elements under load

    Directory of Open Access Journals (Sweden)

    Demchyna B.H.


    Full Text Available It is known that cell concretes are almost immediately destroyed under load, having reached certain critical stresses. Such kind of destruction is called a “catastrophic failure”. Process of crack formation is one of the main factors, influencing process of concrete destruction. Modern theory of crack formation is mainly based on the Griffith theory of destruction. However, the mentioned theory does not completely correspond to the structure of cell concrete with its cell structure, because the theory is intended for a solid body. The article presents one of the possible variants of modelling of the structure of cell concrete and gives some assumptions concerning the process of crack formation in such hollow, not solid environment.

  7. Image reconstruction under non-Gaussian noise

    DEFF Research Database (Denmark)

    Sciacchitano, Federica

    During acquisition and transmission, images are often blurred and corrupted by noise. One of the fundamental tasks of image processing is to reconstruct the clean image from a degraded version. The process of recovering the original image from the data is an example of inverse problem. Due...... that the CM estimate outperforms the MAP estimate, when the error depends on Bregman distances. This PhD project can have many applications in the modern society, in fact the reconstruction of high quality images with less noise and more details enhances the image processing operations, such as edge detection......D thesis intends to solve some of the many open questions for image restoration under non-Gaussian noise. The two main kinds of noise studied in this PhD project are the impulse noise and the Cauchy noise. Impulse noise is due to for instance the malfunctioning pixel elements in the camera sensors, errors...

  8. Superconductivity from magnetic elements under high pressure

    International Nuclear Information System (INIS)

    Shimizu, Katsuya; Amaya, Kiichi; Suzuki, Naoshi; Onuki, Yoshichika


    Can we expect the appearance of superconductivity from magnetic elements? In general, superconductivity occurs in nonmagnetic metal at low temperature and magnetic impurities destroy superconductivity; magnetism and superconductivity are as incompatible as oil and water. Here, we present our experimental example of superconducting elements, iron and oxygen. They are magnetic at ambient pressure, however, they become nonmagnetic under high pressure, then superconductor at low temperature. What is the driving force of the superconductivity? Our understanding in the early stages was a simple scenario that the superconductive state was obtained as a consequence of an emergence of the nonmagnetic states. In both cases, we may consider another scenario for the appearance of superconductivity; the magnetic fluctuation mechanism in the same way as unconventional superconductors

  9. Plasmon instability under four external fields

    International Nuclear Information System (INIS)

    Pereira, R.B.; Fonseca, A.L.A.; Nunes, O.A.C.


    The plasmon instability in a laboratory produced plasma in the presence of four external fields, namely two laser fields, one strong magnetic field and one static electric field, is discussed. The method of unitary transformations is used to transform the problem of electron motion under the four external fields to that of an electron in the presence only of crossed electric and magnetic fields. A kinetic equation for the plasmon population is derived from which the damping (amplification) rate is calculated. We found that the joint action of the four fields results in a relatively larger amplification rate for some values of the static electric field in contrast to the case where no electric field is present. It was also found that the plasmon growth rate favors plasmon wave vectors in an extremely narrow band i.e., the plasmon instability in four external fields is a very selective mechanism for plasmon excitation. (author)

  10. Liquid storage tanks under vertical excitation

    International Nuclear Information System (INIS)

    Philippacopoulos, A.J.


    Until recently, the hydrodynamic effects on liquid storage tanks induced by an earthquake excitation were basically treated for the horizontal component of the earthquake. Recent studies, however, showed that the hydrodynamic effects due to the vertical component of an earthquake may be significant. In these studies the tank is assumed to be fixed at the bottom. This paper is concerned with the hydrodynamic behavior of liquid storage tanks induced by vertical earthquake input excitation. First, the fluid-tank system is treated as a fixed-base system and a simple formula is obtained for the coupled fluid-structure natural frequency. Second, additional interaction effects due to the foundation flexibility on the fluid-tank system are investigated. It is concluded that the foundation flexibility may have a significant effect on the hydrodynamic behavior of the liquid storage tanks under a vertical ground shaking

  11. Mortar constituent of concrete under cyclic compression (United States)

    Maher, A.; Darwin, D.


    The behavior of the mortar constituent of concrete under cyclic compression was studied and a simple analytic model was developed to represent its cyclic behavior. Experimental work consisted of monotonic and cyclic compressive loading of mortar. Two mixes were used, with proportions corresponding to concretes having water cement ratios of 0.5 and 0.6. Forty-four groups of specimens were tested at ages ranging from 5 to 70 days. complete monotonic and cyclic stress strain envelopes were obtained. A number of loading regimes were investigated, including cycles to a constant maximum strain. Major emphasis was placed on tests using relatively high stress cycles. Degradation was shown to be a continuous process and a function of both total strain and load history. No stability or fatigue limit was apparent.

  12. Single Crystals Grown Under Unconstrained Conditions (United States)

    Sunagawa, Ichiro

    Based on detailed investigations on morphology (evolution and variation in external forms), surface microtopography of crystal faces (spirals and etch figures), internal morphology (growth sectors, growth banding and associated impurity partitioning) and perfection (dislocations and other lattice defects) in single crystals, we can deduce how and by what mechanism the crystal grew and experienced fluctuation in growth parameters through its growth and post-growth history under unconstrained condition. The information is useful not only in finding appropriate way to growing highly perfect and homogeneous single crystals, but also in deciphering letters sent from the depth of the Earth and the Space. It is also useful in discriminating synthetic from natural gemstones. In this chapter, available methods to obtain molecular information are briefly summarized, and actual examples to demonstrate the importance of this type of investigations are selected from both natural minerals (diamond, quartz, hematite, corundum, beryl, phlogopite) and synthetic crystals (SiC, diamond, corundum, beryl).

  13. Fatigue in Steel Structures under Random Loading

    DEFF Research Database (Denmark)

    Agerskov, Henning


    test results. Both the fracture mechanics analysis and the fatigue test results indicate that Miner's rule, which is normally used in the design against fatigue in steel structures, may give results, which are unconservative, and that the validity of the results obtained from Miner's rule will depend......Fatigue damage accumulation in steel structures under random loading is studied. The fatigue life of welded joints has been determined both experimentally and from a fracture mechanics analysis. In the experimental part of the investigation, fatigue test series have been carried through on various...... types of welded plate test specimens and full-scale offshore tubular joints. The materials that have been used are either conventional structural steel with a yield stress of ~ 360-410 MPa or high-strength steel with a yield stress of ~ 810-1010 MPa. The fatigue tests and the fracture mechanics analyses...

  14. Carrier multiplication in graphene under Landau quantization. (United States)

    Wendler, Florian; Knorr, Andreas; Malic, Ermin


    Carrier multiplication is a many-particle process giving rise to the generation of multiple electron-hole pairs. This process holds the potential to increase the power conversion efficiency of photovoltaic devices. In graphene, carrier multiplication has been theoretically predicted and recently experimentally observed. However, due to the absence of a bandgap and competing phonon-induced electron-hole recombination, the extraction of charge carriers remains a substantial challenge. Here we present a new strategy to benefit from the gained charge carriers by introducing a Landau quantization that offers a tunable bandgap. Based on microscopic calculations within the framework of the density matrix formalism, we report a significant carrier multiplication in graphene under Landau quantization. Our calculations reveal a high tunability of the effect via externally accessible pump fluence, temperature and the strength of the magnetic field.

  15. Gravitational time advancement under gravity's rainbow (United States)

    Deng, Xue-Mei; Xie, Yi


    Under gravity's rainbow, we investigate its effects on the gravitational time advancement, which is a natural consequence of measuring proper time span for a photon's round trip. This time advancement can be complementary to the time delay for testing the gravity's rainbow, because they are sensitive to different modified dispersion relations (MDRs). Its observability on ranging a spacecraft far from the Earth by two radio and a laser links is estimated at superior conjunction (SC) and inferior conjunction (IC). We find that (1) the IC is more favorable than the SC for measurement on the advancement caused by the rainbow; (2) a specific type of MDR has a significantly larger effect on the advancement than others in both SC and IC cases; and (3) a combination of available optical clocks and the realization of planetary laser ranging in the future will benefit distinguishing the gravity's rainbow from GR by measuring the gravitational time advancement.

  16. Analysis of operator's behaviour under accidental transients

    International Nuclear Information System (INIS)

    Llory, M.; Lemaitre, D.; Griffon-Fouco, C.; Meslin, B.


    Since 1979, EDF has been conducting intensive test campaigns on full-scale PWR simulators in order to study and improve the operators behaviour under incident as well as accident conditions. This paper presents some results obtained during tests carried out in 1986 on the P4 (1300 MWe power plant series) simulators of the Paluel Training Center. These results essentially concern the observed deviations, the diagnosis and the safety engineer's role. They are compared with the results of previous tests on 900 MWe unit simulators. The test organization and methodology, the result analysis methods and the biases introduced by this kind of test are also discussed. (author). 7 refs, 1 fig., 6 figs

  17. Behaviour of bituminized radioactive wastes under irradiation

    International Nuclear Information System (INIS)

    Camaro, S.; Gilardi, T.; Vistoli, P.P.


    Studies are carried out by the CEA in order to predict the behaviour of bituminized radioactive wastes under self irradiation. Bitumen radiolysis produces gas (mainly H 2 ) which diffuses in the organic matrix. If the hydrogen yield is higher than the diffusion flux through the free surface, hydrogen concentration increases and exceeds its solubility in bitumen. Beyond saturation, bubbles are formed and gas is also evacuated by bubbles drift. The aim of these studies is to evaluate the evacuation capacity of radiolytic gas produced in function of initial bituminized wasteform characteristics. A model was developed to achieve this purpose, by calculating the evolution of bubbles population considering all elementary mechanisms of gas evacuation. (authors)

  18. [Temperature Measurement with Bluetooth under Android Platform]. (United States)

    Wang, Shuai; Shen, Hao; Luo, Changze


    To realize the real-time transmission of temperature data and display using the platform of intelligent mobile phone and bluetooth. Application of Arduino Uno R3 in temperature data acquisition of digital temperature sensor DS18B20 acquisition, through the HC-05 bluetooth transmits the data to the intelligent smart phone Android system, realizes transmission of temperature data. Using Java language to write applications program under Android development environment, can achieve real-time temperature data display, storage and drawing temperature fluctuations drawn graphics. Temperature sensor is experimentally tested to meet the body temperature measurement precision and accuracy. This paper can provide a reference for other smart phone mobile medical product development.

  19. Music and Astronomy Under the Stars 2009 (United States)

    Lubowich, D.


    Bring telescopes to where the people are! Music and Astronomy Under the Stars is a three-year NASA-funded astronomy outreach program at community parks during and after music concerts and outdoor family events—such as a Halloween Stars-Spooky Garden Walk. While there have been many astronomy outreach activities and telescope observations at city sidewalks and parks, this program targets a completely different audience: music lovers who are attending summer concerts held in community parks. These music lovers who may never have visited a science museum, planetarium, or star party are exposed to telescope observations and astronomy information with no additional travel costs. Music and Astronomy Under the Stars increased awareness, engagement, and interest in astronomy at classical, pop, rock, and ethnic music concerts. This program includes solar observing before the concerts, telescope observations including a live image projection system, an astronomical video presentation, and astronomy banners/posters. Approximately 500-16,000 people attended each event and 25% to 50% of the people at each event participated in the astronomy program. This program also reached underrepresented and underserved groups (women, minorities, older adults). The target audience (Nassau and Suffolk Counties, New York) is 2,900,000 people, which is larger than combined population of Atlanta, Boston, Denver, Minneapolis, and San Francisco. Although eleven events were planned in 2009, two were canceled due to rain and our largest event, the NY Philharmonic in the Park (attended by 67,000 people in 2008), was cancelled for financial reasons. Our largest event in 2009 was the Tanglewood Music Festival, Lenox MA, attended by 16,000 people where over 5000 people participated in astronomy activities. The Amateur Observers' Society of New York assisted with the NY concerts and the Springfield STARS astronomy club assisted at Tanglewood. In 2009 over 15,000 people participated in astronomy

  20. Portuguese wine regions under a changing climate (United States)

    Santos, João A.; Fraga, Helder; Malheiro, Aureliano C.; Moutinho-Pereira, José; Jones, Gregory V.; Pinto, Joaquim G.


    Viticulture and wine production are among the most important sectors of the Portuguese economy. However, as grapevines are strongly affected by weather and climate, climate change may represent an important threat to wine production. The current (1950-2000) and future (2041-2070) bioclimatic conditions in Portugal are discussed by analyzing a number of indices suitable for viticultural zoning, including a categorized bioclimatic index. A two-step method of spatial pattern downscaling is applied in order to achieve a very high spatial resolution (of approximately 1 km) throughout Portugal. Future projections are based on an ensemble of 13 climate model transient experiments, forced by the SRES A1B emission scenario. Results for the recent past are in clear agreement with the current distribution of vineyards and of the established Denomination of Origin regions. Furthermore, the typical climatic conditions associated with each grapevine variety that are currently grown in Portugal are assessed. Under future scenarios, nevertheless, the current conditions are projected to change significantly towards a lower bioclimatic diversity. This can be explained by the projected warming and drying in future decades. The resulting changes in varietal suitability and wine characteristics of each region may thereby bring important challenges for the Portuguese winemaking sector. As such, new measures need to be timely implemented to adapt to these climate change projections and to mitigate their likely detrimental impacts on the Portuguese economy. Acknowledgments: this work is supported by European Union Funds (FEDER/COMPETE - Operational Competitiveness Programme) and by national funds (FCT - Portuguese Foundation for Science and Technology) under the project ClimVineSafe (PTDC/AGR-ALI/110877/2009).