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Sample records for strong low-velocity anomaly

  1. Seismic Travel Time Tomography in Modeling Low Velocity Anomalies between the Boreholes

    Science.gov (United States)

    Octova, A.; Sule, R.

    2018-04-01

    Travel time cross-hole seismic tomography is applied to describing the structure of the subsurface. The sources are placed at one borehole and some receivers are placed in the others. First arrival travel time data that received by each receiver is used as the input data in seismic tomography method. This research is devided into three steps. The first step is reconstructing the synthetic model based on field parameters. Field parameters are divided into 24 receivers and 45 receivers. The second step is applying inversion process for the field data that consists of five pairs bore holes. The last step is testing quality of tomogram with resolution test. Data processing using FAST software produces an explicit shape and resemble the initial model reconstruction of synthetic model with 45 receivers. The tomography processing in field data indicates cavities in several place between the bore holes. Cavities are identified on BH2A-BH1, BH4A-BH2A and BH4A-BH5 with elongated and rounded structure. In resolution tests using a checker-board, anomalies still can be identified up to 2 meter x 2 meter size. Travel time cross-hole seismic tomography analysis proves this mothod is very good to describing subsurface structure and boundary layer. Size and anomalies position can be recognized and interpreted easily.

  2. P-wave velocity structure beneath the northern Antarctic Peninsula: evidence of a steeply subducting slab and a deep-rooted low-velocity anomaly beneath the central Bransfield Basin

    Science.gov (United States)

    Park, Yongcheol; Kim, Kwang-Hee; Lee, Joohan; Yoo, Hyun Jae; Plasencia L., Milton P.

    2012-12-01

    Upper-mantle structure between 100 and 300 km depth below the northern Antarctic Peninsula is imaged by modelling P-wave traveltime residuals from teleseismic events recorded on the King Sejong Station (KSJ), the Argentinean/Italian stations (JUBA and ESPZ), an IRIS/GSN Station (PMSA) and the Seismic Experiment in Patagonia and Antarctica (SEPA) broad-band stations. For measuring traveltime residuals, we applied a multichannel cross-correlation method and inverted for upper-mantle structure using VanDecar's method. The new 3-D velocity model reveals a subducted slab with a ˜70° dip angle at 100-300 km depth and a strong low-velocity anomaly confined below the SE flank of the central Bransfield Basin. The low velocity is attributed to a thermal anomaly in the mantle that could be as large as 350-560 K and which is associated with high heat flow and volcanism in the central Bransfield Basin. The low-velocity zone imaged below the SE flank of the central Bransfield Basin does not extend under the northern Bransfield Basin, suggesting that the rifting process in that area likely involves different geodynamic processes.

  3. Thermal infrared anomalies of several strong earthquakes.

    Science.gov (United States)

    Wei, Congxin; Zhang, Yuansheng; Guo, Xiao; Hui, Shaoxing; Qin, Manzhong; Zhang, Ying

    2013-01-01

    In the history of earthquake thermal infrared research, it is undeniable that before and after strong earthquakes there are significant thermal infrared anomalies which have been interpreted as preseismic precursor in earthquake prediction and forecasting. In this paper, we studied the characteristics of thermal radiation observed before and after the 8 great earthquakes with magnitude up to Ms7.0 by using the satellite infrared remote sensing information. We used new types of data and method to extract the useful anomaly information. Based on the analyses of 8 earthquakes, we got the results as follows. (1) There are significant thermal radiation anomalies before and after earthquakes for all cases. The overall performance of anomalies includes two main stages: expanding first and narrowing later. We easily extracted and identified such seismic anomalies by method of "time-frequency relative power spectrum." (2) There exist evident and different characteristic periods and magnitudes of thermal abnormal radiation for each case. (3) Thermal radiation anomalies are closely related to the geological structure. (4) Thermal radiation has obvious characteristics in abnormal duration, range, and morphology. In summary, we should be sure that earthquake thermal infrared anomalies as useful earthquake precursor can be used in earthquake prediction and forecasting.

  4. Optical spectral weight anomalies and strong correlation

    International Nuclear Information System (INIS)

    Toschi, A.; Capone, M.; Ortolani, M.; Calvani, P.; Lupi, S.; Castellani, C.

    2007-01-01

    The anomalous behavior observed in the optical spectral weight (W) of the cuprates provides valuable information about the physics of these compounds. Both the doping and the temperature dependences of W are hardly explained through conventional estimates based on the f-sum rule. By computing the optical conductivity of the doped Hubbard model with the Dynamical Mean Field Theory, we point out that the strong correlation plays a key role in determining the basic features of the observed anomalies: the proximity to a Mott insulating phase accounts simultaneously for the strong temperature dependence of W and for its zero temperature value

  5. Anomalies

    International Nuclear Information System (INIS)

    Bardeen, W.A.

    1985-08-01

    Anomalies have a diverse impact on many aspects of physical phenomena. The role of anomalies in determining physical structure from the amplitude for π 0 decay to the foundations of superstring theory will be reviewed. 36 refs

  6. Ultra-low velocity zone heterogeneities at the core-mantle boundary from diffracted PKKPab waves

    Science.gov (United States)

    Ma, Xiaolong; Sun, Xinlei

    2017-08-01

    Diffracted waves around Earth's core could provide important information of the lowermost mantle that other seismic waves may not. We examined PKKPab diffraction waves from 52 earthquakes occurring at the western Pacific region and recorded by USArray to probe the velocity structure along the core-mantle boundary (CMB). These diffracted waves emerge at distances up to 10° past the theoretical cutoff epicentral distance and show comparable amplitudes. We measured the ray parameters of PKKPab diffraction waves by Radon transform analysis that is suitable for large-aperture arrays. These ray parameters show a wide range of values from 4.250 to 4.840 s/deg, suggesting strong lateral heterogeneities in sampling regions at the base of the mantle. We further estimated the P-wave velocity variations by converting these ray parameters and found the CMB regions beneath the northwestern edge of African Anomaly (Ritsma et al. in Science 286:1925-1928, 1999) and southern Sumatra Islands exhibit velocity reductions up to 8.5% relative to PREM. We suggest that these low velocity regions are Ultra-low velocity zones, which may be related to partial melt or iron-enriched solids.[Figure not available: see fulltext.

  7. Upper mantle low velocity heterogeneities beneath NE China revealed by source- and receiver-side converted waves

    Science.gov (United States)

    Guan, Z.; Niu, F.

    2017-12-01

    Common-conversion-point (CCP) stacking of receiver function is a powerful tool in mapping upper mantle heterogeneities. However, reverberations from shallow boundaries with large velocity contrast could contaminate the imaging profiles severely. Applying the refined Slowness Weighted CCP (SWCCP) stacking technique (Guan and Niu, 2017) on NECESSArray data, we eliminated the multiple effects and systematically imaged the upper mantle low velocity heterogeneities in NE China where there exist rich unconsolidated sediments. The SWCCP profiles reveal a 350 km low velocity heterogeneity which is possibly associated with the Changbai Mountain volcanism and interpreted as a negatively buoyant silicate melt lying atop of the 410 km discontinuity. Besides, the imaging results are also suggestive of a sporadic 580-620 km low velocity heterogeneity locating in the easternmost part of NE China with a velocity contrast comparable with the 660-km discontinuity. In addition, between 42º N and 45º N, we also found a double 660-km discontinuity at the two sides of the localized depression in the longitudinal range of 128º E to 131º E. On the other hand, we gathered USArray and Alaska regional array seismic data of deep earthquakes occurring beneath NE China and the surrounding areas and employed stacking technique to study the source side S-to-P conversions. The source-side stacking also showed a strong S-to-P conversion at 600 km deep, consistent with the SWCCP stacks. Meanwhile, we also confirmed the double 660-km discontinuity feature from the source-side conversions. The receiver- and source-side observations provide strong constraints on these low velocity anomalies that may offer insights on the subduction dynamics of the Pacific plate.

  8. Low-velocity superconducting accelerating structures

    International Nuclear Information System (INIS)

    Delayen, J.R.

    1990-01-01

    The present paper reviews the status of RF superconductivity as applied to low-velocity accelerating properties. Heavy-ion accelerators must accelerate efficiently particles which travel at a velocity much smaller than that of light particles, whose velocity changes along accelerator, and also different particles which have different velocity profiles. Heavy-ion superconducting accelerators operate at frequencies which are lower than high-energy superconducting accelerators. The present paper first discusses the basic features of heavy-ion superconducting structures and linacs. Design choices are then addressed focusing on structure geometry, materials, frequency, phase control, and focusing. The report also gives an outline of the status of superconducting booster projects currently under way at the Argonne National Laboratory, SUNY Stony Brook, Weizmann Institute, University of Washington, Florida State, Saclay, Kansas State, Daresbury, Japanese Atomic Energy Research Institute, Legnaro, Bombay, Sao Paulo, ANU (Canberra), and Munich. Recent developments and future prospects are also described. (N.K.) 68 refs

  9. Thermal anomalies detection before strong earthquakes (M > 6.0 using interquartile, wavelet and Kalman filter methods

    Directory of Open Access Journals (Sweden)

    M. Akhoondzadeh

    2011-04-01

    Full Text Available Thermal anomaly is known as a significant precursor of strong earthquakes, therefore Land Surface Temperature (LST time series have been analyzed in this study to locate relevant anomalous variations prior to the Bam (26 December 2003, Zarand (22 February 2005 and Borujerd (31 March 2006 earthquakes. The duration of the three datasets which are comprised of MODIS LST images is 44, 28 and 46 days for the Bam, Zarand and Borujerd earthquakes, respectively. In order to exclude variations of LST from temperature seasonal effects, Air Temperature (AT data derived from the meteorological stations close to the earthquakes epicenters have been taken into account. The detection of thermal anomalies has been assessed using interquartile, wavelet transform and Kalman filter methods, each presenting its own independent property in anomaly detection. The interquartile method has been used to construct the higher and lower bounds in LST data to detect disturbed states outside the bounds which might be associated with impending earthquakes. The wavelet transform method has been used to locate local maxima within each time series of LST data for identifying earthquake anomalies by a predefined threshold. Also, the prediction property of the Kalman filter has been used in the detection process of prominent LST anomalies. The results concerning the methodology indicate that the interquartile method is capable of detecting the highest intensity anomaly values, the wavelet transform is sensitive to sudden changes, and the Kalman filter method significantly detects the highest unpredictable variations of LST. The three methods detected anomalous occurrences during 1 to 20 days prior to the earthquakes showing close agreement in results found between the different applied methods on LST data in the detection of pre-seismic anomalies. The proposed method for anomaly detection was also applied on regions irrelevant to earthquakes for which no anomaly was detected

  10. Prediction of North Pacific Height Anomalies During Strong Madden-Julian Oscillation Events

    Science.gov (United States)

    Kai-Chih, T.; Barnes, E. A.; Maloney, E. D.

    2017-12-01

    The Madden Julian Oscillation (MJO) creates strong variations in extratropical atmospheric circulations that have important implications for subseasonal-to-seasonal prediction. In particular, certain MJO phases are characterized by a consistent modulation of geopotential height in the North Pacific and adjacent regions across different MJO events. Until recently, only limited research has examined the relationship between these robust MJO tropical-extratropical teleconnections and model prediction skill. In this study, reanalysis data (MERRA and ERA-Interim) and ECMWF ensemble hindcasts are used to demonstrate that robust teleconnections in specific MJO phases and time lags are also characterized by excellent agreement in the prediction of geopotential height anoma- lies across model ensemble members at forecast leads of up to 3 weeks. These periods of enhanced prediction capabilities extend the possibility for skillful extratropical weather prediction beyond traditional 10-13 day limits. Furthermore, we also examine the phase dependency of teleconnection robustness by using Linear Baroclinic Model (LBM) and the result is consistent with the ensemble hindcasts : the anomalous heating of MJO phase 2 (phase 6) can consistently generate positive (negative) geopotential height anomalies around the extratropical Pacific with a lead of 15-20 days, while other phases are more sensitive to the variaion of the mean state.

  11. Indentation of aluminium foam at low velocity

    Directory of Open Access Journals (Sweden)

    Shi Xiaopeng

    2015-01-01

    Full Text Available The indentation behaviour of aluminium foams at low velocity (10 m/s ∼ 30 m/s was investigated both in experiments and numerical simulation in this paper. A flat-ended indenter was used and the force-displacement history was recorded. The Split Hopkinson Pressure bar was used to obtain the indentation velocity and forces in the dynamic experiments. Because of the low strength of the aluminium foam, PMMA bar was used, and the experimental data were corrected using Bacon's method. The energy absorption characteristics varying with impact velocity were then obtained. It was found that the energy absorption ability of aluminium foam gradually increases in the quasi-static regime and shows a significant increase at ∼10 m/s velocity. Numerical simulation was also conducted to investigate this process. A 3D Voronoi model was used and models with different relative densities were investigated as well as those with different failure strain. The indentation energy increases with both the relative density and failure strain. The analysis of the FE model implies that the significant change in energy absorption ability of aluminium foam in indentation at ∼10 m/s velocity may be caused by plastic wave effect.

  12. Recognition of possible strong earthquake epicenters. VII. Use of gravitational Bouguer anomaly for California and adjacent regions

    Energy Technology Data Exchange (ETDEWEB)

    Artem' ev, M E; Rotvain, I M; Sadovskii, A M

    1977-01-01

    The possibility of using gravimetric data (Bouguer anomalies) as initial material for determining possible strong earthquake epicenters is determined with the aid of recognition algorithms. This was done for the purpose of correlating geological-geomorphological results and analyzing gravimetric indicators obtained in the study. 9 references, 4 figures, 6 tables.

  13. Size-dependent avoidance of a strong magnetic anomaly in Caribbean spiny lobsters.

    Science.gov (United States)

    Ernst, David A; Lohmann, Kenneth J

    2018-03-01

    On a global scale, the geomagnetic field varies predictably across the Earth's surface, providing animals that migrate long distances with a reliable source of directional and positional information that can be used to guide their movements. In some locations, however, magnetic minerals in the Earth's crust generate an additional field that enhances or diminishes the overall field, resulting in unusually steep gradients of field intensity within a limited area. How animals respond to such magnetic anomalies is unclear. The Caribbean spiny lobster, Panulirus argus , is a benthic marine invertebrate that possesses a magnetic sense and is likely to encounter magnetic anomalies during migratory movements and homing. As a first step toward investigating whether such anomalies affect the behavior of lobsters, a two-choice preference experiment was conducted in which lobsters were allowed to select one of two artificial dens, one beneath a neodymium magnet and the other beneath a non-magnetic weight of similar size and mass (control). Significantly more lobsters selected the control den, demonstrating avoidance of the magnetic anomaly. In addition, lobster size was found to be a significant predictor of den choice: lobsters that selected the anomaly den were significantly smaller as a group than those that chose the control den. Taken together, these findings provide additional evidence for magnetoreception in spiny lobsters, raise the possibility of an ontogenetic shift in how lobsters respond to magnetic fields, and suggest that magnetic anomalies might influence lobster movement in the natural environment. © 2018. Published by The Company of Biologists Ltd.

  14. On plasma coupling and turbulence effects in low velocity stopping

    Energy Technology Data Exchange (ETDEWEB)

    Kurilenkov, Yu K [Unified Institute for High Temperatures of Russian Academy of Sciences, 13/19 Izhorskaya Str., 125412 Moscow (Russian Federation); Maynard, G [Laboratoire de Physique des Gaz et des Plasmas, UMR-8578, Bat. 210, Universite Paris XI, F-91405 Orsay (France); Barriga-Carrasco, M D [Laboratoire de Physique des Gaz et des Plasmas, UMR-8578, Bat. 210, Universite Paris XI, F-91405 Orsay (France); Valuev, A A [Unified Institute for High Temperatures of Russian Academy of Sciences, 13/19 Izhorskaya Str., 125412 Moscow (Russian Federation)

    2006-04-28

    The problem of stopping power (SP) for projectile ions is analysed in terms of the dielectric function and effective collision frequency for moderately dense and strongly coupled plasmas (SCP). We consider several issues regarding the calculation of stopping power for correlated ensembles of particles and oscillators. In particular, effects of group (few particle) modes, transition from positive to negative dispersion and excitation of collective modes up to suprathermal level at plasma targets are addressed. Linear SP of dense suprathermal (nonlinear) plasma targets at different levels of target plasma turbulence is estimated. The force of suprathermal plasma oscillations on the projectile ions is mostly in the nature of increased frictional drag. The results obtained show the possibility of increasing low velocity stopping (up to 'turbulent' values) in comparison with losses in equilibrium dense plasma targets. Experimental conditions to create specific turbulent targets as well as some connection between stopping phenomena and SCP transport properties are discussed briefly.

  15. On plasma coupling and turbulence effects in low velocity stopping

    International Nuclear Information System (INIS)

    Kurilenkov, Yu K; Maynard, G; Barriga-Carrasco, M D; Valuev, A A

    2006-01-01

    The problem of stopping power (SP) for projectile ions is analysed in terms of the dielectric function and effective collision frequency for moderately dense and strongly coupled plasmas (SCP). We consider several issues regarding the calculation of stopping power for correlated ensembles of particles and oscillators. In particular, effects of group (few particle) modes, transition from positive to negative dispersion and excitation of collective modes up to suprathermal level at plasma targets are addressed. Linear SP of dense suprathermal (nonlinear) plasma targets at different levels of target plasma turbulence is estimated. The force of suprathermal plasma oscillations on the projectile ions is mostly in the nature of increased frictional drag. The results obtained show the possibility of increasing low velocity stopping (up to 'turbulent' values) in comparison with losses in equilibrium dense plasma targets. Experimental conditions to create specific turbulent targets as well as some connection between stopping phenomena and SCP transport properties are discussed briefly

  16. Influence of calculation error of total field anomaly in strongly magnetic environments

    Science.gov (United States)

    Yuan, Xiaoyu; Yao, Changli; Zheng, Yuanman; Li, Zelin

    2016-04-01

    An assumption made in many magnetic interpretation techniques is that ΔTact (total field anomaly - the measurement given by total field magnetometers, after we remove the main geomagnetic field, T0) can be approximated mathematically by ΔTpro (the projection of anomalous field vector in the direction of the earth's normal field). In order to meet the demand for high-precision processing of magnetic prospecting, the approximate error E between ΔTact and ΔTpro is studied in this research. Generally speaking, the error E is extremely small when anomalies not greater than about 0.2T0. However, the errorE may be large in highly magnetic environments. This leads to significant effects on subsequent quantitative inference. Therefore, we investigate the error E through numerical experiments of high-susceptibility bodies. A systematic error analysis was made by using a 2-D elliptic cylinder model. Error analysis show that the magnitude of ΔTact is usually larger than that of ΔTpro. This imply that a theoretical anomaly computed without accounting for the error E overestimate the anomaly associated with the body. It is demonstrated through numerical experiments that the error E is obvious and should not be ignored. It is also shown that the curves of ΔTpro and the error E had a certain symmetry when the directions of magnetization and geomagnetic field changed. To be more specific, the Emax (the maximum of the error E) appeared above the center of the magnetic body when the magnetic parameters are determined. Some other characteristics about the error Eare discovered. For instance, the curve of Emax with respect to the latitude was symmetrical on both sides of magnetic equator, and the extremum of the Emax can always be found in the mid-latitudes, and so on. It is also demonstrated that the error Ehas great influence on magnetic processing transformation and inversion results. It is conclude that when the bodies have highly magnetic susceptibilities, the error E can

  17. Investigation on low velocity impact resistance of SMA composite material

    Science.gov (United States)

    Hu, Dianyin; Zhang, Long; Wang, Rongqiao; Zhang, Xiaoyong

    2016-04-01

    A method to improve low velocity impact resistance of aeroengine composite casing using shape memory alloy's properties of shape memory(SM) and super-elasticity(SE) is proposed in this study. Firstly, a numerical modeling of SMA reinforced composite laminate under low velocity impact load with impact velocity of 10 m/s is established based on its constitutive model implemented by the VUMAT subroutine of commercial software ABAQUS. Secondly, the responses of SMA composite laminate including stress and deflection distributions were achieved through transient analysis under low velocity impact load. Numerical results show that both peak stress and deflection values of SMA composite laminate are less than that without SMA, which proves that embedding SMA into the composite structure can effectively improve the low velocity impact performance of composite structure. Finally, the influence of SM and SE on low velocity impact resistance is quantitatively investigated. The values of peak stress and deflection of SMA composite based on SM property decrease by 18.28% and 9.43% respectively, compared with those without SMA, instead of 12.87% and 5.19% based on SE. In conclusion, this proposed model described the impact damage of SMA composite structure and turned to be a more beneficial method to enhance the impact resistance by utilizing SM effect.

  18. Effect of strong correlations on the high energy anomaly in hole- and electron-doped high-Tc superconductors

    International Nuclear Information System (INIS)

    Moritz, B; Johnston, S; Greven, M; Shen, Z-X; Devereaux, T P; Schmitt, F; Meevasana, W; Motoyama, E M; Lu, D H; Kim, C; Scalettar, R T

    2009-01-01

    Recently, angle-resolved photoemission spectroscopy (ARPES) has been used to highlight an anomalously large band renormalization at high binding energies in cuprate superconductors: the high energy 'waterfall' or high energy anomaly (HEA). This paper demonstrates, using a combination of new ARPES measurements and quantum Monte Carlo simulations, that the HEA is not simply the by-product of matrix element effects, but rather represents a cross-over from a quasi-particle band at low binding energies near the Fermi level to valence bands at higher binding energy, assumed to be of strong oxygen character, in both hole- and electron-doped cuprates. While photoemission matrix elements clearly play a role in changing the aesthetic appearance of the band dispersion, i.e. the 'waterfall'-like behavior, they provide an inadequate description for the physics that underlies the strong band renormalization giving rise to the HEA. Model calculations of the single-band Hubbard Hamiltonian showcase the role played by correlations in the formation of the HEA and uncover significant differences in the HEA energy scale for hole- and electron-doped cuprates. In addition, this approach properly captures the transfer of spectral weight accompanying both hole and electron doping in a correlated material and provides a unifying description of the HEA across both sides of the cuprate phase diagram.

  19. On a stabilization mechanism for low-velocity detonations

    KAUST Repository

    Sow, Aliou; Semenko, Roman E.; Kasimov, Aslan R.

    2017-01-01

    We use numerical simulations of the reactive Lula equations to analyse the nonlinear stability of steady-state one-dimensional solutions for gaseous detonations in the presence of both momentum and heat losses. Our results point to a possible stabilization mechanism for the low-velocity detonations in such systems. The mechanism stems from the existence of a one-parameter family of solutions found in Semenko el al.

  20. On a stabilization mechanism for low-velocity detonations

    KAUST Repository

    Sow, Aliou

    2017-03-08

    We use numerical simulations of the reactive Lula equations to analyse the nonlinear stability of steady-state one-dimensional solutions for gaseous detonations in the presence of both momentum and heat losses. Our results point to a possible stabilization mechanism for the low-velocity detonations in such systems. The mechanism stems from the existence of a one-parameter family of solutions found in Semenko el al.

  1. Low velocity impact of 6082-T6 aluminum plates

    Science.gov (United States)

    Mocian, Oana Alexandra; Constantinescu, Dan Mihai; Sandu, Marin; Sorohan, Ştefan

    2018-02-01

    The low velocity domain covers vehicle impacts, ship collisions and even accidentally tool drops. Even though more and more research is needed into these fields, most of the papers concerning impact problems focus on impact at medium and high velocities. Understanding the behavior of structures subjected to low velocity impact is of major importance when referring to impact resistance and damage tolerance. The paper presents an experimental and numerical investigation on the low velocity behavior of 6082-T6 aluminum plates. Impact tests were performed using an Instron Ceast 9340 drop-weight testing machine. In the experimental procedure, square plates were mounted on a circular support, fixed with a pneumatic clamping system and impacted with a hemispherical steel projectile. Specimens were impacted at constant weight and different impact velocities. The effect of different impact energies was investigated. The impact event was then simulated using the nonlinear finite element code LS_DYNA in order to determine the effect of strain rate upon the mechanical behavior of the aluminum plates. Moreover, in order to capture the exact behavior of the material, a special attention has been given to the selection of the correct material model and its parameters, which, in large extent, depend on the observed behavior of the aluminum plate during the test and the actual response of the plate under simulation. The numerical predictions are compared with the experimental observations and the applicability of the numerical model for further researches is analyzed.

  2. Growth anomalies on the coral genera Acropora and Porites are strongly associated with host density and human population size across the Indo-Pacific.

    Directory of Open Access Journals (Sweden)

    Greta S Aeby

    2011-02-01

    Full Text Available Growth anomalies (GAs are common, tumor-like diseases that can cause significant morbidity and decreased fecundity in the major Indo-Pacific reef-building coral genera, Acropora and Porites. GAs are unusually tractable for testing hypotheses about drivers of coral disease because of their pan-Pacific distributions, relatively high occurrence, and unambiguous ease of identification. We modeled multiple disease-environment associations that may underlie the prevalence of Acropora growth anomalies (AGA (n = 304 surveys and Porites growth anomalies (PGA (n = 602 surveys from across the Indo-Pacific. Nine predictor variables were modeled, including coral host abundance, human population size, and sea surface temperature and ultra-violet radiation anomalies. Prevalence of both AGAs and PGAs were strongly host density-dependent. PGAs additionally showed strong positive associations with human population size. Although this association has been widely posited, this is one of the first broad-scale studies unambiguously linking a coral disease with human population size. These results emphasize that individual coral diseases can show relatively distinct patterns of association with environmental predictors, even in similar diseases (growth anomalies found on different host genera (Acropora vs. Porites. As human densities and environmental degradation increase globally, the prevalence of coral diseases like PGAs could increase accordingly, halted only perhaps by declines in host density below thresholds required for disease establishment.

  3. Growth anomalies on the coral genera Acropora and Porites are strongly associated with host density and human population size across the Indo-Pacific

    Science.gov (United States)

    Aeby, Greta S.; Williams, Gareth J.; Franklin, Erik C.; Haapkyla, Jessica; Harvell, C. Drew; Neale, Stephen; Page, Cathie A.; Raymundo, Laurie; Vargas-Angel, Bernardo; Willis, Bette L.; Work, Thierry M.; Davy, Simon K.

    2011-01-01

    Growth anomalies (GAs) are common, tumor-like diseases that can cause significant morbidity and decreased fecundity in the major Indo-Pacific reef-building coral genera, Acropora and Porites. GAs are unusually tractable for testing hypotheses about drivers of coral disease because of their pan-Pacific distributions, relatively high occurrence, and unambiguous ease of identification. We modeled multiple disease-environment associations that may underlie the prevalence of Acropora growth anomalies (AGA) (n = 304 surveys) and Porites growth anomalies (PGA) (n = 602 surveys) from across the Indo-Pacific. Nine predictor variables were modeled, including coral host abundance, human population size, and sea surface temperature and ultra-violet radiation anomalies. Prevalence of both AGAs and PGAs were strongly host density-dependent. PGAs additionally showed strong positive associations with human population size. Although this association has been widely posited, this is one of the first broad-scale studies unambiguously linking a coral disease with human population size. These results emphasize that individual coral diseases can show relatively distinct patterns of association with environmental predictors, even in similar diseases (growth anomalies) found on different host genera (Acropora vs. Porites). As human densities and environmental degradation increase globally, the prevalence of coral diseases like PGAs could increase accordingly, halted only perhaps by declines in host density below thresholds required for disease establishment.

  4. Modeling delamination of FRP laminates under low velocity impact

    Science.gov (United States)

    Jiang, Z.; Wen, H. M.; Ren, S. L.

    2017-09-01

    Fiber reinforced plastic laminates (FRP) have been increasingly used in various engineering such as aeronautics, astronautics, transportation, naval architecture and their impact response and failure are a major concern in academic community. A new numerical model is suggested for fiber reinforced plastic composites. The model considers that FRP laminates has been constituted by unidirectional laminated plates with adhesive layers. A modified adhesive layer damage model that considering strain rate effects is incorporated into the ABAQUS / EXPLICIT finite element program by the user-defined material subroutine VUMAT. It transpires that the present model predicted delamination is in good agreement with the experimental results for low velocity impact.

  5. Superconducting accelerating structures for very low velocity ion beams

    Directory of Open Access Journals (Sweden)

    J. Xu

    2008-03-01

    Full Text Available This paper presents designs for four types of very-low-velocity superconducting (SC accelerating cavity capable of providing several MV of accelerating potential per cavity, and suitable for particle velocities in the range 0.006low-velocity applications.

  6. Damage in woven CFRP laminates subjected to low velocity impacts

    International Nuclear Information System (INIS)

    Ullah, H; Abdel-Wahab, A A; Harland, A R; Silberschmidt, V V

    2012-01-01

    Carbon fabric-reinforced polymer (CFRP) composites used in sports products can be exposed to different in-service conditions such as large dynamic bending deformations caused by impact loading. Composite materials subjected to such loads demonstrate various damage modes such as matrix cracking, delamination and, ultimately, fabric fracture. Damage evolution in these materials affects both their in-service properties and performance that can deteriorate with time. These processes need adequate means of analysis and investigation, the major approaches being experimental characterisation and non-destructive examination of internal damage in composite laminates. This research deals with a deformation behaviour and damage in woven composite laminates due to low-velocity dynamic out-of-plane bending. Experimental tests are carried out to characterise the behaviour of such laminates under large-deflection dynamic bending in un-notched specimens in Izod tests using a Resil Impactor. A series of low-velocity impact tests is carried out at various levels of impact energy to assess the energy absorbed and force-time response of CFRP laminates. X-ray micro computed tomography (micro-CT) is used to investigate material damage modes in the impacted specimens. X-ray tomographs revealed that through-thickness matrix cracking, inter-ply delamination and intra-ply delamination, such as tow debonding and fabric fracture, were the prominent damage modes.

  7. Superconducting accelerating structures for very low velocity ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Xu, J.; Shepard, K.W.; Ostroumov, P.N.; Fuerst, J.D.; Waldschmidt, G.; /Argonne; Gonin, I.V.; /Fermilab

    2008-01-01

    This paper presents designs for four types of very-low-velocity superconducting accelerating cavity capable of providing several MV of accelerating potential per cavity, and suitable for particle velocities in the range 0.006 < v/c < 0.06. Superconducting TEM-class cavities have been widely applied to CW acceleration of ion beams. SC linacs can be formed as an array of independently-phased cavities, enabling a variable velocity profile to maximize the output energy for each of a number of different ion species. Several laboratories in the US and Europe are planning exotic beam facilities based on SC linacs. The cavity designs presented here are intended for the front-end of such linacs, particularly for the post-acceleration of rare isotopes of low charge state. Several types of SC cavities have been developed recently to cover particle velocities above 0.06c. Superconducting four-gap quarter-wave resonators for velocities 0.008 < {beta} = v/c < 0.05 were developed about two decades ago and have been successfully operated at the ATLAS SC linac at Argonne National Laboratory. Since that time, progress in simulation tools, cavity fabrication and processing have increased SC cavity gradients by a factor of 3-4. This paper applies these tools to optimize the design of a four-gap quarter-wave resonator for exotic beam facilities and other low-velocity applications.

  8. Design of low velocity-spread cusp guns for axis encircling beams

    International Nuclear Information System (INIS)

    Lawson, W.

    1987-01-01

    The design of a novel electron gun suitable for intense beam cyclotron resonance devices is introduced here. An annular Pierce-type gun is used in conjunction with an unbalanced nonadiabatic field reversal and an adiabatic compression region to produce an axis-encircling beam. This beam is ideally suited for interaction with electromagnetic waves that have strong on-axis electric fields (e.g., the TE 0 /sub 11/ mode). Low velocity spreads are achieved by utilizing the beam self-fields in the compression region and by focusing in the Pierce gun

  9. Development of a very-low-velocity superconducting linac

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.

    1987-01-01

    Four types of superconducting accelerator structures are being developed for use in a low velocity positive-ion injector linac for the ATLAS heavy-ion accelerator. Prototypes of the first two of these have been tested. The structures are all variants of a quarter-wave line terminated with a four-gap interdigital drift-tube array. The two structure types so far tested operate at 48.5 mHz and have an active length of 10 cm (for the particle velocity - .008c type) and 16.5 cm (for the velocity - .014c type). Effective accelerating fields of 10 MV/m have been achieved with the 10 cm structure, corresponding to an effective accelerating potential of 1 MV. The 16.5 cm structure has been operated at field levels of 6 MV/m, also giving an effective potential of 1 MV. Prototypes of the remaining two resonant geometries are under construction.

  10. Development of a very-low-velocity superconducting linac

    International Nuclear Information System (INIS)

    Shepard, K.W.

    1987-01-01

    Four types of superconducting accelerator structures are being developed for use in a low velocity positive-ion injector linac for the ATLAS heavy-ion accelerator. Prototypes of the first two of these have been tested. The structures are all variants of a quarter-wave line terminated with a four-gap interdigital drift-tube array. The two structure types so far tested operate at 48.5 mHz and have an active length of 10 cm (for the particle velocity - .008c type) and 16.5 cm (for the velocity - .014c type). Effective accelerating fields of 10 MV/m have been achieved with the 10 cm structure, corresponding to an effective accelerating potential of 1 MV. The 16.5 cm structure has been operated at field levels of 6 MV/m, also giving an effective potential of 1 MV. Prototypes of the remaining two resonant geometries are under construction

  11. A detonation model of high/low velocity detonation

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Shaoming; Li, Chenfang; Ma, Yunhua; Cui, Junmin [Xian Modern Chemistry Research Institute, Xian, 710065 (China)

    2007-02-15

    A new detonation model that can simulate both high and low velocity detonations is established using the least action principle. The least action principle is valid for mechanics and thermodynamics associated with a detonation process. Therefore, the least action principle is valid in detonation science. In this model, thermodynamic equilibrium state is taken as the known final point of the detonation process. Thermodynamic potentials are analogous to mechanical ones, and the Lagrangian function in the detonation process is L=T-V. Under certain assumptions, the variation calculus of the Lagrangian function gives two solutions: the first one is a constant temperature solution, and the second one is the solution of an ordinary differential equation. A special solution of the ordinary differential equation is given. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  12. Low velocity encounters of minor bodies with the outer planets

    International Nuclear Information System (INIS)

    Carusi, A.; Perozzi, E.; Valsecchi, G.B.

    1983-01-01

    Previous studies of close encounters of minor bodies with Jupiter have shown that the perturbations are stronger either if the encounter is very deep or if the velocity of the minor body relative to the planet is low. In the present research the author investigates the effects of low velocity encounters between fictitious minor bodies and the four outer planets. Two possible outcomes of this type of encounter are the temporary satellite capture of the minor body by the planet, and the exchange of perihelion with aphelion of the minor body orbit. Different occurrence rates of these processes are found for different planets, and the implications for the orbital evolution of minor bodies in the outer Solar System are discussed. (Auth.)

  13. Fatigue Performance of Composite Laminates After Low-velocity Impact

    Directory of Open Access Journals (Sweden)

    LIANG Xiao-lin

    2016-12-01

    Full Text Available Compression-compression fatigue tests were carried out on T300/5405 composite laminates after low-velocity impact, compression performance of the laminates with different impact damages was studied together with its fatigue life and damage propagation under different stress levels, then the effects of impact energy, stress level and damage propagation on fatigue life of laminates were discussed. The results indicate that impact damage can greatly reduce the residual strength of laminates; under low fatigue load levels, the higher impact energy is, the shorter the fatigue life of laminates with impact damage will be; damage propagation undergoes two stages during the fatigue test, namely the steady propagation and the rapid propagation, accounting for 80% and 20% of the overall fatigue life, respectively; damage propagation rate decreases with the reduction of stress level.

  14. Modelling low velocity impact induced damage in composite laminates

    Science.gov (United States)

    Shi, Yu; Soutis, Constantinos

    2017-12-01

    The paper presents recent progress on modelling low velocity impact induced damage in fibre reinforced composite laminates. It is important to understand the mechanisms of barely visible impact damage (BVID) and how it affects structural performance. To reduce labour intensive testing, the development of finite element (FE) techniques for simulating impact damage becomes essential and recent effort by the composites research community is reviewed in this work. The FE predicted damage initiation and propagation can be validated by Non Destructive Techniques (NDT) that gives confidence to the developed numerical damage models. A reliable damage simulation can assist the design process to optimise laminate configurations, reduce weight and improve performance of components and structures used in aircraft construction.

  15. Low Velocity Sphere Impact of a Borosilicate Glass

    Energy Technology Data Exchange (ETDEWEB)

    Morrissey, Timothy G [ORNL; Ferber, Mattison K [ORNL; Wereszczak, Andrew A [ORNL; Fox, Ethan E [ORNL

    2012-05-01

    This report summarizes US Army TARDEC sponsored work at Oak Ridge National Laboratory (ORNL) involving low velocity (< 30 m/s or < 65 mph) ball impact testing of Borofloat borosilicate glass, and is a follow-up to a similar study completed by the authors on Starphire soda-lime silicate glass last year. The response of the borosilicate glass to impact testing at different angles was also studied. The Borofloat glass was supplied by the US Army Research Laboratory and its tin-side was impacted or indented. The intent was to better understand low velocity impact response in the Borofloat. Seven sphere materials were used whose densities bracket that of rock: borosilicate glass, soda-lime silicate glass, silicon nitride, aluminum oxide, zirconium oxide, carbon steel, and a chrome steel. A gas gun or a ball-drop test setup was used to produce controlled velocity delivery of the spheres against the glass tile targets. Minimum impact velocities to initiate fracture in the Borofloat were measured and interpreted in context to the kinetic energy of impact and the elastic property mismatch between the seven sphere-Borofloat-target combinations. The primary observations from this low velocity (< 30 m/s or < 65 mph) testing were: (1) BS glass responded similarly to soda-lime silicate glass when spherically indented but quite differently under sphere impact conditions; (2) Frictional effects contributed to fracture initiation in BS glass when it spherically indented. This effect was also observed with soda-lime silicate glass; (3) The force necessary to initiate fracture in BS glass under spherical impact decreases with increasing elastic modulus of the sphere material. This trend is opposite to what was observed with soda-lime silicate glass. Friction cannot explain this trend and the authors do not have a legitimate explanation for it yet; (4) The force necessary to initiate contact-induced fracture is higher under dynamic conditions than under quasi-static conditions. That

  16. Electron capture by highly charged low-velocity ions

    International Nuclear Information System (INIS)

    Cocke, C.L.; Dubois, R.; Justiniano, E.; Gray, T.J.; Can, C.

    1982-01-01

    This paper describes the use of a fast heavy ion beam to produce, by bombardment of gaseous targets, highly-charged low-velocity recoil ions, and the use of these secondary ions in turn as projectiles in studies of electron capture and ionization in low-energy collision systems. The interest in collisions involving low-energy highly-charged projectiles comes both from the somewhat simplifying aspects of the physics which attend the long-range capture and from applications to fusion plasmas, astrophysics and more speculative technology such as the production of X-ray lasers. The ions of interest in such applications should have both electronic excitation and center-of-mass energies in the keV range and cannot be produced by simply stripping fast heavy ion beams. Several novel types of ion source have been developed to produce low-energy highly-charged ions, of which the secondary ion recoil source discussed in this paper is one. (Auth.)

  17. Initial Examination of Low Velocity Sphere Impact of Glass Ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Morrissey, Timothy G [ORNL; Fox, Ethan E [ORNL; Wereszczak, Andrew A [ORNL; Ferber, Mattison K [ORNL

    2012-06-01

    This report summarizes US Army TARDEC sponsored work at Oak Ridge National Laboratory (ORNL) involving low velocity (< 30 m/s or < 65 mph) sphere impact testing of two materials from the lithium aluminosilicate family reinforced with different amounts of ceramic particulate, i.e., glass-ceramic materials, SCHOTT Resistan{trademark}-G1 and SCHOTT Resistan{trademark}-L. Both materials are provided by SCHOTT Glass (Duryea, PA). This work is a follow-up to similar sphere impact studies completed by the authors on PPG's Starphire{reg_sign} soda-lime silicate glass and SCHOTT BOROFLOAT{reg_sign} borosilicate glass. A gas gun or a sphere-drop test setup was used to produce controlled velocity delivery of silicon nitride (Si{sub 3}N{sub 4}) spheres against the glass ceramic tile targets. Minimum impact velocities to initiate fracture in the glass-ceramics were measured and interpreted in context to the kinetic energy of impact and the elastic property mismatch between sphere and target material. Quasistatic spherical indentation was also performed on both glass ceramics and their contact damage responses were compared to those of soda-lime silicate and borosilicate glasses. Lastly, variability of contact damage response was assessed by performing spherical indentation testing across the area of an entire glass ceramic tile. The primary observations from this low velocity (< 30 m/s or < 65 mph) testing were: (1) Resistan{trademark}-L glass ceramic required the highest velocity of sphere impact for damage to initiate. Starphire{reg_sign} soda-lime silicate glass was second best, then Resistan{trademark}-G1 glass ceramic, and then BOROFLOAT{reg_sign} borosilicate glass. (2) Glass-ceramic Resistan{trademark}-L also required the largest force to initiate ring crack from quasi-static indentation. That ranking was followed, in descending order, by Starphire{reg_sign} soda-lime silicate glass, Resistan{trademark}-G1 glass ceramic, and BOROFLOAT{reg_sign} borosilicate glass

  18. Investigating Ultra-low Velocity Zones beneath the Southwestern Pacific

    Science.gov (United States)

    Carson, S. E.; Hansen, S. E.; Garnero, E.

    2017-12-01

    The core mantle boundary (CMB), where the solid silicate mantle meets the liquid iron-nickel outer core, represents the largest density contrast on our planet, and it has long been recognized that the CMB is associated with significant structural heterogeneities. One CMB structure of particular interest are ultra low-velocity zones (ULVZs), laterally-varying, 5-50 km thick isolated patches seen in some locations just above the CMB that are associated with increased density and reduced seismic wave velocities. These variable characteristics have led to many questions regarding ULVZ origins, but less than 40% of the CMB has been surveyed for the presence of ULVZs given limited seismic coverage of the lowermost mantle. Therefore, investigations that sample the CMB with new geometries are critical to further our understanding of ULVZs and their potential connection to other deep Earth processes. The Transantarctic Mountains Northern Network (TAMNNET), a 15-station seismic array that was recently deployed in Antarctica, provides a unique dataset to further study ULVZ structure with new and unique path geometry. Core-reflected ScP and PcP phases from the TAMNNET dataset particularly well sample the CMB in the vicinity of New Zealand in the southwestern Pacific, providing coverage between an area to the north where ULVZ structure has been previously identified and another region to the south, which shows no ULVZ evidence. By identifying and modeling pre- and post-cursor ScP and PcP energy, we are exploring a new portion of the CMB with a goal of better understanding potential ULVZ origins. Our study area also crosses the southern boundary of the Pacific Large Low Shear Velocity Province (LLSVP); therefore, our investigations may allow us to examine the possible relationship between LLSVPs and ULVZs.

  19. Low-velocity impact cratering experiments in granular slopes

    Science.gov (United States)

    Hayashi, Kosuke; Sumita, Ikuro

    2017-07-01

    Low-velocity impact cratering experiments are conducted in sloped granular targets to study the effect of the slope angle θ on the crater shape and its scales. We use two types of granular matter, sand and glass beads, former of which has a larger friction coefficient μs = tanθr , where θr is the angle of repose. Experiments show that as θ increases, the crater becomes shallower and elongated in the direction of the slope. Furthermore the crater floor steepens in the upslope side and a thick rim forms in the downslope side, thus forming an asymmetric profile. High-speed images show that these features are results of ejecta being dispersed farther towards the downslope side and the subsequent avalanche which buries much of the crater floor. Such asymmetric ejecta dispersal can be explained by combining the Z-model and a ballistic model. Using the topographic maps of the craters, we classify crater shape regimes I-III, which transition with increasing θ : a full-rim crater (I), a broken-rim crater (II), and a depression (III). The critical θ for the regime transitions are larger for sand compared to glass beads, but collapse to close values when we use a normalized slope θ^ = tanθ / tanθr . Similarly we derive θ^-dependences of the scaled crater depth, length, width and their ratios which collapse the results for different targets and impact energies. We compare the crater profiles formed in our experiments with deep craters on asteroid Vesta and find that some of the scaled profiles nearly overlap and many have similar depth / length ratios. This suggests that these Vestan craters may also have formed in the gravity regime and that the formation process can be approximated by a granular flow with a similar effective friction coefficient.

  20. Development of Hydroxyl Tagging Velocimetry for Low Velocity Flows

    Science.gov (United States)

    Andre, Matthieu A.; Bardet, Philippe M.; Burns, Ross A.; Danehy, Paul M.

    2016-01-01

    Hydroxyl tagging velocimetry (HTV) is a molecular tagging technique that relies on the photo-dissociation of water vapor into OH radicals and their subsequent tracking using laser induced fluorescence. Velocities are then obtained from time-of-flight calculations. At ambient temperature in air, the OH species lifetime is relatively short (<50 µs), making it suited for high speed flows. Lifetime and radicals formation increases with temperature, which allows HTV to also probe low-velocity, high-temperature flows or reacting flows such as flames. The present work aims at extending the domain of applicability of HTV, particularly towards low-speed (<10 m/s) and moderate (<500 K) temperature flows. Results are compared to particle image velocimetry (PIV) measurements recorded in identical conditions. Single shot and averaged velocity profiles are obtained in an air jet at room temperature. By modestly raising the temperature (100-200 degC) the OH production increases, resulting in an improvement of the signal-to-noise ratio (SNR). Use of nitrogen - a non-reactive gas with minimal collisional quenching - extends the OH species lifetime (to over 500 µs), which allows probing of slower flows or, alternately, increases the measurement precision at the expense of spatial resolution. Instantaneous velocity profiles are resolved in a 100degC nitrogen jet (maximum jet-center velocity of 6.5 m/s) with an uncertainty down to 0.10 m/s (1.5%) at 68% confidence level. MTV measurements are compared with particle image velocimetry and show agreement within 2%.

  1. Simulation and low velocity impact testing on confined explosives

    NARCIS (Netherlands)

    Scholtes, J.H.G.; Verbeek, H.J.

    2010-01-01

    TNO Defence Security and Safety, performs in depth research in energetic material responses to several Insensitive Munitions (IM) stimuli like cook-off, bullet-fragment impact and shaped charge impact. The response of energetic materials to these stimuli depends strongly on the properties of these

  2. SHARP - II. Mass structure in strong lenses is not necessarily dark matter substructure: a flux ratio anomaly from an edge-on disc in B1555+375

    NARCIS (Netherlands)

    Hsueh, J. -W; Fassnacht, C. D.; Vegetti, S.; McKean, J. P.; Spingola, C.; Auger, M. W.; Koopmans, L. V. E.; Lagattuta, D. J.

    2016-01-01

    Gravitational lens flux-ratio anomalies provide a powerful technique for measuring dark matter substructure in distant galaxies. However, before using these flux-ratio anomalies to test galaxy formation models, it is imperative to ascertain that the given anomalies are indeed due to the presence of

  3. Effect of strong correlations on the high energy anomaly in hole- and electron-doped high-T{sub c} superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Moritz, B; Johnston, S; Greven, M; Shen, Z-X; Devereaux, T P [Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory and Stanford University, Stanford, CA 94305 (United States); Schmitt, F; Meevasana, W; Motoyama, E M [Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305 (United States); Lu, D H [Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Kim, C [Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749 (Korea, Republic of); Scalettar, R T [Physics Department, University of California-Davis, Davis, CA 95616 (United States)], E-mail: moritzb@slac.stanford.edu

    2009-09-15

    Recently, angle-resolved photoemission spectroscopy (ARPES) has been used to highlight an anomalously large band renormalization at high binding energies in cuprate superconductors: the high energy 'waterfall' or high energy anomaly (HEA). This paper demonstrates, using a combination of new ARPES measurements and quantum Monte Carlo simulations, that the HEA is not simply the by-product of matrix element effects, but rather represents a cross-over from a quasi-particle band at low binding energies near the Fermi level to valence bands at higher binding energy, assumed to be of strong oxygen character, in both hole- and electron-doped cuprates. While photoemission matrix elements clearly play a role in changing the aesthetic appearance of the band dispersion, i.e. the 'waterfall'-like behavior, they provide an inadequate description for the physics that underlies the strong band renormalization giving rise to the HEA. Model calculations of the single-band Hubbard Hamiltonian showcase the role played by correlations in the formation of the HEA and uncover significant differences in the HEA energy scale for hole- and electron-doped cuprates. In addition, this approach properly captures the transfer of spectral weight accompanying both hole and electron doping in a correlated material and provides a unifying description of the HEA across both sides of the cuprate phase diagram.

  4. The structure of a jet in cross flow at low velocity ratios

    International Nuclear Information System (INIS)

    Gopalan, Shridhar; Abraham, Bruce M.; Katz, Joseph

    2004-01-01

    This paper examines in detail the flow structure and associated wall pressure fluctuations caused by the injection of a round, turbulent jet into a turbulent boundary layer. The velocity ratio, r, ratio of mean jet velocity to the mean cross flow, varies from 0.5 to 2.5 and the Reynolds number based on the cross flow speed and jet diameter is 1.9x10 4 . Particle image velocimetry is used to measure the flow and flush mounted pressure sensors installed at several locations used to determine the wall pressure. The results consist of sample instantaneous flow structures, distributions of mean velocity, vorticity and turbulence intensity, as well as wall pressure spectra. The flow structure depends strongly on the velocity ratio and there are two distinctly different regions. At low velocity ratios, namely r 2, the near-wall flow behind the jet resembles a Karman vortex street and the wall-normal vortical structures contain cross flow boundary layer vorticity. Autospectra of the pressure signals show that the effect of the jet is mainly in the 15-100 Hz range. At r 2, the wall pressure levels reach a plateau demonstrating the diminishing effect of the jet on the near-wall flow. Consistent with the flow structure, the highest wall pressure fluctuations occur off the jet centerline for r 2. Also, the advection speed of near-wall vortical structures increase with r at r 2 it is a constant

  5. Comparison of different methods for the determination of dynamic characteristics of low velocity anemometers

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Popiolek, Z.

    2004-01-01

    Three methods for determining the dynamic characteristics of low velocity thermal anemometers were compared. They were: step-up velocity change and step-down velocity change methods and a method based on sinusoidal type velocity fluctuations. Two low velocity thermal anemometers with omnidirectio......Three methods for determining the dynamic characteristics of low velocity thermal anemometers were compared. They were: step-up velocity change and step-down velocity change methods and a method based on sinusoidal type velocity fluctuations. Two low velocity thermal anemometers...... with omnidirectional velocity sensors were tested. The results identify differences in frequency response of low velocity anemometers determined by the three methods. The time constant and the response time determined by the step-up velocity change method and the step-down velocity change method may be substantially...... different and insufficient for describing the frequency response of all low velocity thermal anemometers. Therefore the upper frequency, determined in tests with sinusoidal velocity fluctuations, is recommended to be used in indoor climate standards as a single parameter describing the dynamic...

  6. Hot-Wire Calibration at Low Velocities: Revisiting the Vortex Shedding Method

    Directory of Open Access Journals (Sweden)

    Sohrab S. Sattarzadeh

    2013-01-01

    Full Text Available The necessity to calibrate hot-wire probes against a known velocity causes problems at low velocities, due to the inherent inaccuracy of pressure transducers at low differential pressures. The vortex shedding calibration method is in this respect a recommended technique to obtain calibration data at low velocities, due to its simplicity and accuracy. However, it has mainly been applied in a low and narrow Reynolds number range known as the laminar vortex shedding regime. Here, on the other hand, we propose to utilize the irregular vortex shedding regime and show where the probe needs to be placed with respect to the cylinder in order to obtain unambiguous calibration data.

  7. Low velocity collisions of porous planetesimals in the early solar system

    Science.gov (United States)

    de Niem, D.; Kührt, E.; Hviid, S.; Davidsson, B.

    2018-02-01

    The ESA Rosetta mission has shown that Comet 67P/Churuymov-Gerasimenko is bi-lobed, has a high average porosity of around 70%, does not have internal cavities on size scales larger than 10 m, the lobes could have individual sets of onion shell-like layering, and the nucleus surface contains 100 m-scale cylindrical pits. It is currently debated whether these properties are consistent with high-velocity collisional evolution or if they necessarily are surviving signatures of low-velocity primordial accretion. We use an Eulerian hydrocode to study collisions between highly porous bodies of different sizes, material parameters and relative velocities with emphasis on 5-100 m/s to characterize the effects of collisions in terms of deformation, compaction, and heating. We find that accretion of 1 km cometesimals by 3 km nuclei at 13.5 m/s flattens and partially buries the cometesimal with ∼ 1% reduction of the bulk porosity. This structure locally becomes more dense but the global effect of compaction is minor, suggesting that low-velocity accretion does not lead to a 'bunch of grapes' structure with large internal cavities but a more homogeneous interior, consistent with Rosetta findings. The mild local compaction associated with accretion is potentially the origin of the observed nucleus layering. In 2D axially symmetric impacts hit-and-stick collisions of similarly-sized nuclei are possible at velocities up to 30 m/s where deformation becomes severe. The bulk porosity is reduced significantly, even at 30-50 m/s relative velocity. To avoid hit-and-run collisions the impact angle must be less than 35°-45° from the surface normal at 10 m/s, and even smaller at higher velocities. Impact heating is insignificant. We find that the small cross section of the 67P neck may require a ≤ 5 m/s impact, unless the cohesion exceeds 10 kPa. We conclude that bi-lobe nucleus formation is possible at velocities typically discussed in hierarchical growth scenarios. Impacts of a 7 m

  8. Low Velocity Impact Behavior of Basalt Fiber-Reinforced Polymer Composites

    Science.gov (United States)

    Shishevan, Farzin Azimpour; Akbulut, Hamid; Mohtadi-Bonab, M. A.

    2017-06-01

    In this research, we studied low velocity impact response of homogenous basalt fiber-reinforced polymer (BFRP) composites and then compared the impact key parameters with carbon fiber-reinforced polymer (CFRP) homogenous composites. BFRPs and CFRPs were fabricated by vacuum-assisted resin transfer molding (VARTM) method. Fabricated composites included 60% fiber and 40% epoxy matrix. Basalt and carbon fibers used as reinforcement materials were weaved in 2/2 twill textile tip in the structures of BFRP and CFRP composites. We also utilized the energy profile method to determine penetration and perforation threshold energies. The low velocity impact tests were carried out in 30, 60, 80, 100, 120 and 160 J energy magnitudes, and impact response of BFRPs was investigated by related force-deflection, force-time, deflection-time and absorbed energy-time graphics. The related impact key parameters such as maximum contact force, absorbed energy, deflection and duration time were compared with CFRPs for various impact energy levels. As a result, due to the higher toughness of basalt fibers, a better low velocity impact performance of BFRP than that of CFRP was observed. The effects of fabrication parameters, such as curing process, were studied on the low velocity impact behavior of BFRP. The results of tested new fabricated materials show that the change of fabrication process and curing conditions improves the impact behavior of BFRPs up to 13%.

  9. Lithospheric low-velocity zones associated with a magmatic segment of the Tanzanian Rift, East Africa

    Science.gov (United States)

    Plasman, M.; Tiberi, C.; Ebinger, C.; Gautier, S.; Albaric, J.; Peyrat, S.; Déverchère, J.; Le Gall, B.; Tarits, P.; Roecker, S.; Wambura, F.; Muzuka, A.; Mulibo, G.; Mtelela, K.; Msabi, M.; Kianji, G.; Hautot, S.; Perrot, J.; Gama, R.

    2017-07-01

    Rifting in a cratonic lithosphere is strongly controlled by several interacting processes including crust/mantle rheology, magmatism, inherited structure and stress regime. In order to better understand how these physical parameters interact, a 2 yr long seismological experiment has been carried out in the North Tanzanian Divergence (NTD), at the southern tip of the eastern magmatic branch of the East African rift, where the southward-propagating continental rift is at its earliest stage. We analyse teleseismic data from 38 broad-band stations ca. 25 km spaced and present here results from their receiver function (RF) analysis. The crustal thickness and Vp/Vs ratio are retrieved over a ca. 200 × 200 km2 area encompassing the South Kenya magmatic rift, the NTD and the Ngorongoro-Kilimanjaro transverse volcanic chain. Cratonic nature of the lithosphere is clearly evinced through thick (up to ca. 40 km) homogeneous crust beneath the rift shoulders. Where rifting is present, Moho rises up to 27 km depth and the crust is strongly layered with clear velocity contrasts in the RF signal. The Vp/Vs ratio reaches its highest values (ca. 1.9) beneath volcanic edifices location and thinner crust, advocating for melting within the crust. We also clearly identify two major low-velocity zones (LVZs) within the NTD, one in the lower crust and the second in the upper part of the mantle. The first one starts at 15-18 km depth and correlates well with recent tomographic models. This LVZ does not always coexist with high Vp/Vs ratio, pleading for a supplementary source of velocity decrease, such as temperature or composition. At a greater depth of ca. 60 km, a mid-lithospheric discontinuity roughly mimics the step-like and symmetrically outward-dipping geometry of the Moho but with a more slanting direction (NE-SW) compared to the NS rift. By comparison with synthetic RF, we estimate the associated velocity reduction to be 8-9 per cent. We relate this interface to melt ponding

  10. Calibration techniques for the hot wire anemometer in a low velocity region

    International Nuclear Information System (INIS)

    Fujimura, Kaoru; Kawamura, Hiroshi

    1980-03-01

    In connection with experiments on coolant flow in the core of multi-purpose VHTR, a low-velocity calibration wind tunnel was made, and techniques for the hot wire anemometer in the air were investigated. Following are the results. 1) A technique using the frequency of von Karman vortex street is not recommended because of the irregular mode in a low velocity region. 2) A Pitot tube is valid only for the flow velocities larger than 1 m/s. 3) The thermal trace technique is suitable in a relatively wide range of velocity, if velocity defect in the wake is compensated for. When flow velocity is larger than 1 m/s, the thermal trace technique is consistent with the Pitot tube method. (author)

  11. K-shell ionisation cross sections for W, Au and U by low velocity protons

    International Nuclear Information System (INIS)

    Castro Faria, N.V. de; Freire Junior, F.L.; Montenegro, E.C.; Pinho, A.G. de; Silveira, E.F. da.

    1984-01-01

    Proton-induced K-shell ionisation cross section for W, Au and U by low velocity protons were obtained from thick target measurements. For the first time the lowest incident energy reached a value less than 10 times the binding energy of the K-shell electron (less than 9 times in the case of Au). Possible errors are thoroughly examined and a comparison with other available experimental results and theoretical values is presented and discussed. (Author) [pt

  12. Research on carbon fiber–reinforced plastic bumper beam subjected to low-velocity frontal impact

    OpenAIRE

    Yefa Hu; Can Liu; Jinguang Zhang; Guoping Ding; Qiong Wu

    2015-01-01

    Lightweight and safety performance of automobiles are two important factors for automobile designs. In this article, a research on lightweight and crashworthiness of automotive bumper has been conducted. The carbon fiber–reinforced plastic bumper beam is considered to replace the traditional high-strength steel one. The low-velocity impact finite element simulations for the above two bumper beams are performed via LS-DYNA. Furthermore, the energy absorption capabilities and dynamic response c...

  13. Low velocity gunshot wounds result in significant contamination regardless of ballistic characteristics.

    Science.gov (United States)

    Weinstein, Joseph; Putney, Emily; Egol, Kenneth

    2014-01-01

    Controversy exists among the orthopedic community regarding the treatment of gunshot injuries. No consistent treatment algorithm exists for treatment of low energy gunshot wound (GSW) trauma. The purpose of this study was to critically examine the wound contamination following low velocity GSW based upon bullet caliber and clothing fiber type found within the injury track. Four types of handguns were fired at ballistic gel from a 10-foot distance. Various clothing materials were applied (denim, cotton, polyester, and wool) circumferentially around the tissue agar in a loose manor. A total of 32 specimens were examined. Each caliber handgun was fired a minimum of 5 times into a gel. Regardless of bullet caliber there was gross contamination of the entire bullet track in 100% of specimens in all scenarios and for all fiber types. Furthermore, as would be expected, the degree of contamination appeared to increase as the size of the bullet increased. Low velocity GSWs result in significant contamination regardless of bullet caliber and jacket type. Based upon our results further investigation of low velocity GSW tracks is warranted. Further clinical investigation should focus on the degree to which debridement should be undertaken.

  14. A comparative study on low-velocity impact response of fabric composite laminates

    International Nuclear Information System (INIS)

    Zhang, Diantang; Sun, Ying; Chen, Li; Pan, Ning

    2013-01-01

    Highlights: • We examine the low-velocity behavior of single-ply 3D orthogonal woven fabric composites. • Three-coordinate measuring device was used to acquire the 3D topographies. • Single-ply 3D orthogonal woven fabric composites show better impact performance. • Impact properties will increase if in-plane yarns and Z-yarns of single-ply 3D orthogonal woven fabric are optimized. - Abstract: Impact behaviors at low velocity of composite laminates reinforced with fabrics of different architectures are investigated. Unidirectional prepreg, 2D woven and 3D orthogonal fabrics, all formed of Ultrahigh Molecular Weight Polyethylene (UHMWPE) filaments, were selected as reinforcements to form composite laminates using hot pressing technology. Low velocity impact tests were conducted using a drop-weight impact equipment at the energy level of 35 J. A three-coordinate measuring device was employed to determine the volume of plastic deformation and surface dent diameter. The results show that the composite laminates of single-ply 3D orthogonal woven fabric exhibit better energy absorbed capacity and impact damage resistance as compared to those of unidirectional and 2D plain-woven fabric

  15. Influence of the Metal Volume Fraction on the permanent dent depth and energy absorption of GLARE plates subjected to low velocity impact

    Science.gov (United States)

    Bikakis, GSE; Savaidis, A.; Zalimidis, P.; Tsitos, S.

    2016-11-01

    Fiber-metal laminates are hybrid composite materials, consisting of alternating metal layers bonded to fiber-reinforced prepreg layers. GLARE (GLAss REinforced) belongs to this new family of materials. GLARE is the most successful fiber-metal laminate up to now and is currently being used for the construction of primary aerospace structures, such as the fuselage of the Airbus A380 air plane. Impact properties are very important in aerospace structures, since impact damage is caused by various sources, such as maintenance damage from dropped tools, collision between service cars or cargo and the structure, bird strikes and hail. The principal objective of this article is to evaluate the influence of the Metal Volume Fraction (MVF) on the low velocity impact response of GLARE fiber-metal laminates. Previously published differential equations of motion are employed for this purpose. The low velocity impact behavior of various circular GLARE plates is predicted and characteristic values of impact variables, which represent the impact phenomenon, are evaluated versus the corresponding MVF of the examined GLARE material grades. The considered GLARE plates are subjected to low velocity impact under identical impact conditions. A strong effect of the MVF on the maximum impact load and a significant effect on the maximum plate deflection of GLARE plates has been found.

  16. Influence of the Metal Volume Fraction on the maximum deflection and impact load of GLARE plates subjected to low velocity impact

    Science.gov (United States)

    Bikakis, GSE; Savaidis, A.; Zalimidis, P.; Tsitos, S.

    2016-11-01

    Fiber-metal laminates are hybrid composite materials, consisting of alternating metal layers bonded to fiber-reinforced prepreg layers. GLARE (GLAss REinforced) belongs to this new family of materials. GLARE is the most successful fiber-metal laminate up to now and is currently being used for the construction of primary aerospace structures, such as the fuselage of the Airbus A380 air plane. Impact properties are very important in aerospace structures, since impact damage is caused by various sources, such as maintenance damage from dropped tools, collision between service cars or cargo and the structure, bird strikes and hail. The principal objective of this article is to evaluate the influence of the Metal Volume Fraction (MVF) on the low velocity impact response of GLARE fiber-metal laminates. Previously published differential equations of motion are employed for this purpose. The low velocity impact behavior of various circular GLARE plates is predicted and characteristic values of impact variables, which represent the impact phenomenon, are evaluated versus the corresponding MVF of the examined GLARE material grades. The considered GLARE plates are subjected to low velocity impact under identical impact conditions. A strong effect of the MVF on the maximum impact load and a significant effect on the maximum plate deflection of GLARE plates has been found.

  17. THE VELOCITY DISTRIBUTION OF NEARBY STARS FROM HIPPARCOS DATA. II. THE NATURE OF THE LOW-VELOCITY MOVING GROUPS

    International Nuclear Information System (INIS)

    Bovy, Jo; Hogg, David W.

    2010-01-01

    The velocity distribution of nearby stars (∼<100 pc) contains many overdensities or 'moving groups', clumps of comoving stars, that are inconsistent with the standard assumption of an axisymmetric, time-independent, and steady-state Galaxy. We study the age and metallicity properties of the low-velocity moving groups based on the reconstruction of the local velocity distribution in Paper I of this series. We perform stringent, conservative hypothesis testing to establish for each of these moving groups whether it could conceivably consist of a coeval population of stars. We conclude that they do not: the moving groups are neither trivially associated with their eponymous open clusters nor with any other inhomogeneous star formation event. Concerning a possible dynamical origin of the moving groups, we test whether any of the moving groups has a higher or lower metallicity than the background population of thin disk stars, as would generically be the case if the moving groups are associated with resonances of the bar or spiral structure. We find clear evidence that the Hyades moving group has higher than average metallicity and weak evidence that the Sirius moving group has lower than average metallicity, which could indicate that these two groups are related to the inner Lindblad resonance of the spiral structure. Further, we find weak evidence that the Hercules moving group has higher than average metallicity, as would be the case if it is associated with the bar's outer Lindblad resonance. The Pleiades moving group shows no clear metallicity anomaly, arguing against a common dynamical origin for the Hyades and Pleiades groups. Overall, however, the moving groups are barely distinguishable from the background population of stars, raising the likelihood that the moving groups are associated with transient perturbations.

  18. Gravitational anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Leutwyler, H; Mallik, S

    1986-12-01

    The effective action for fermions moving in external gravitational and gauge fields is analyzed in terms of the corresponding external field propagator. The central object in our approach is the covariant energy-momentum tensor which is extracted from the regular part of the propagator at short distances. It is shown that the Lorentz anomaly, the conformal anomaly and the gauge anomaly can be expressed in terms of the local polynomials which determine the singular part of the propagator. (There are no coordinate anomalies). Except for the conformal anomaly, for which we give explicit representations only in dless than or equal to4, we consider an arbitrary number of dimensions.

  19. Flowfield characterisation in the wake of a low-velocity heated sphere anemometer

    Energy Technology Data Exchange (ETDEWEB)

    Olim, A.M. [Associacao para o Desenvolvimento da Aerodinamica Industrial (ADAI), Coimbra (Portugal); Riethmuller, M.L. [Von Karman Institute for Fluid Dynamics (VKI), St. Genese (Belgium); Gameiro da Silva, M.C. [Departamento de Engenharia Mecanica, Faculdade de Ciencias e Tecnologia, Universidade de Coimbra Polo II, Coimbra (Portugal)

    2002-06-01

    Heated sphere anemometers (HSA) are the most widely used instruments for low-velocity measurements in the heating, ventilation and air-conditioning industry. Experiments were conducted to characterise the flowfield around the spherically shaped sensor and upper probe assembly of a HSA. Particle image velocimetry was the main quantitative experimental technique. Measurements of the flowfield around a HSA probe and a 2:1 scaled-up model were performed in a uniform isothermal axisymmetrical jet air flow at Re around 350, based on sensor diameter, for different pitch angle incident flows. Additionally, extensive flow visualisation studies around scaled-up models of the HSA probe were performed. (orig.)

  20. Accuracy limitations for low velocity measurements and draft assessment in rooms

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Popiolek, Zbigniew J.; Silva, M.G.

    2007-01-01

    must be known in order to perform reliable assessment and validation. At present, a low-velocity thermal anemometer (LVTA) with an omnidirectional (spherical) sensor is most often used in practice for measuring air speed due to its low price and easy and convenient operation. The accuracy of the speed......, the definition of realistic requirements in thermal comfort standards as well as validation of CFD predictions is made possible.......The measurement of air temperature, mean air speed, and turbulence intensity is required in order to assess air distribution and draft discomfort in ventilated rooms. The measurements are also used for validation of computational fluid dynamics (CFD) predictions. The uncertainty of the measurements...

  1. Heavy-ion stopping powers and the low-velocity-projectile z3 effect

    International Nuclear Information System (INIS)

    Porter, L.E.

    1977-01-01

    Recent heavy-ion stopping-power measurements with elemental solid targets have been analyzed in order to ascertain the influence on effective ion charge of incorporating the low-velocity-projectile z 3 effect in Bethe-Bloch calculations. Shell corrections and the mean excitation energy of a given target were held fixed while searching for the best-fit value of a single charge-state parameter. In general, excellent fits to the stopping powers at projectile energies above 0.3 MeV/amu were achieved. Results of the present study compare very favorably with those from other extant methods of analysis

  2. Analytical and Numerical Study of Foam-Filled Corrugated Core Sandwich Panels under Low Velocity Impact

    Directory of Open Access Journals (Sweden)

    Mohammad Nouri Damghani

    2016-05-01

    Full Text Available Analytical and finite element simulations are used to predict the effect of core density on the energy absorption of composite sandwich panels under low-velocity impact. The composite sandwich panel contains two facesheets and a foam-filled corrugated core. Analytical model is defined as a two degree-of-freedom system based on equivalent mass, spring, and dashpot to predict the local and global deformation response of a simply supported panel. The results signify a good agreement between analytical and numerical predictions.

  3. Imaging pockets and conduits of low velocity material beneath the lithosphere of the Atlas Mountains of Morocco: links to volcanism and orogenesis

    Science.gov (United States)

    Miller, M. S.; Sun, D.; O'Driscoll, L.; Holt, A.; Butcher, A.; Becker, T. W.; Diaz Cusi, J.; Thomas, C.

    2014-12-01

    The Atlas Mountains of Morocco have unusually high topography, with no apparent deep crustal root, and regions of localized Cenozoic alkaline volcanism. Previous seismic imaging and geophysical studies have implied a hot mantle upwelling as the source of the volcanism and high elevation, but the existence and physical properties of such an upwelling are debated. Recent temporary deployments of over 100 broadband seismometers that extended across Morocco as part of the PICASSO, Morocco-Münster, and IberArray experiments along with select permanent stations have provided a dataset to image the detailed mantle and lithospheric structure beneath the Atlas. We present results from S receiver functions (SRF), shear wave splitting, waveform modeling, and geodynamic models that help constrain the tectonic evolution of the Atlas and the localized alkaline volcanism. The receiver functions show that the lithosphere is thin (~65 km) beneath the Atlas, but thickens (~105 km) over a very short length scale at the flanks of the mountains and near the Quaternary volcanoes. These changes in lithospheric thickness also correspond to dramatic decreases in delay times inferred from S and SKS splitting observations. SRFs also indicate a broad, low seismic velocity anomaly (~150 km) below the shallow lithosphere that extends along much of the Atlas and beneath the Anti-Atlas and correlates with the location of Pliocene-Quaternary magmatism. Waveform analysis from the linear array across the Middle and High Atlas constrains the position, shape, and physical characteristics of a localized, low velocity conduit that extends up from the uppermost mantle (~200 km). The shape, position and temperature of the imaged low velocity anomaly, offsets in the lithosphere-asthenosphere boundary, and correlation with mantle flow inferred from shear wave splitting suggest that the unusually high topography of the Atlas Mountains is due to active mantle support.

  4. Ultrasonic detection of spall damage nucleation under low-velocity repeated impact

    Directory of Open Access Journals (Sweden)

    Watanabe T.

    2012-08-01

    Full Text Available Repeated plate impact testing with impact stress well below the threshold spall-stress (2.6 GPa on medium carbon steel was carried out to the identical target plate by impacting the flyer plate. Occurrence of spall damage under low-velocity repeated impact was evaluated nondestructively with a low frequency scanning acoustic microscope. We observed the spall damage distribution by the B- and C-scan images. In order to initiate the spall damage (voids in a ductile material or cracks in a brittle one the particular value of threshold spall-stress should be exceeded what already belongs to a commonly accepted knowledge. Generally, the spall damage development is dependent on the amplitude and the duration of the stress pulse. If the stress is high and duration is long enough to create tensile failure of material, the voids or cracks nucleate along the spall plane, and consequently, they form macrocracks. Therefore, the spall damage does not create when the first impact stress is less than the threshold spall-stress. However, after the fifth low-velocity repeated impact test, the generation of the spall damage was detected, even if the impact stress (1.1–1.7 GPa was lower than the threshold spall-stress (2.6 GPa.

  5. Current injection phase thermography for low-velocity impact damage identification in composite laminates

    International Nuclear Information System (INIS)

    Grammatikos, S.A.; Kordatos, E.Z.; Matikas, T.E.; David, C.; Paipetis, A.S.

    2014-01-01

    Highlights: • A novel Current injection phase thermography NDE method has been developed. • Blind impact damage has been successfully detected in composite laminates. • Carbon nanotubes enhance detection by improving of through thickness conductivity. • Detection is feasible with considerably less energy than for IR excited thermography. - Abstract: An innovative non-destructive evaluation (NDE) technique is presented based on current stimulated thermography. Modulated electric current is injected to Carbon Fibre Reinforced Plastics (CFRP) laminates as an external source of thermal excitation. Pulsed Phase Thermography (PPT) is concurrently employed to identify low velocity impact induced (LVI) damage. The efficiency of the proposed method is demonstrated for both plain and with Carbon Nanotubes (CNTs) modified laminates, which are subjected to low-velocity impact damaged composite laminates at different energy levels. The presence of the nano reinforcing phase is important in achieving a uniform current flow along the laminate, as it improves the through thickness conductivity. The acquired thermographs are compared with optical PPT, C-scan images and Computer Tomography (CT) representations. The typical energy input for successful damage identification with current injection is three to four orders of magnitude less compared to the energy required for optical PPT

  6. Low velocity impact on polymer composite plates in contact with water

    Directory of Open Access Journals (Sweden)

    Y Kwon

    2016-09-01

    Full Text Available In this study, composite materials were tested in two different environments to determine the role of Fluid Structure Interaction with composites under a low velocity impact. This was done using a low velocity impact machine and polymer composite plates. The composite is made of laminated symmetrical plain weave E-glass fabrics. The test area of the composite plates is 30.5 cm by 30.5 cm with clamped boundary conditions. The testing was done using a drop weight system to impact the center of the test area. One testing was performed with composite plates in air, called dry impact. The other testing was conducted while composite plates were submerged in water, called wet impact. A Plexiglas box in conjunction with the impact machine was used to keep the top of the composite sample dry while it was submerged in an anechoic water tank, so called water-backed air impact. Output from the tests was recorded using strain gauges and a force impact sensor. The results show that an added mass effect from the water plays a large role in the Fluid Structure Interaction with composites due to the similar densities of water and the composites. The wet impact results in a larger impact force and damage than the dry impact under the same impact condition, i.e., the same impact mass and drop height.

  7. Finite element simulation of low velocity impact loading on a sandwich composite

    Directory of Open Access Journals (Sweden)

    Vishwas M.

    2018-01-01

    Full Text Available Sandwich structure offer more advantage in bringing flexural stiffness and energy absorption capabilities in the application of automobile and aerospace components. This paper presents comparison study and analysis of two types of composite sandwich structures, one having Jute Epoxy skins with rubber core and the other having Glass Epoxy skins with rubber core subjected to low velocity normal impact loading. The behaviour of sandwich structure with various parameters such as energy absorption, peak load developed, deformation and von Mises stress and strain, are analyzed using commercially available analysis software. The results confirm that sandwich composite with jute epoxy skin absorbs approximately 20% more energy than glass epoxy skin. The contact force developed in jute epoxy skin is approximately 2.3 times less when compared to glass epoxy skin. von Mises stress developed is less in case of jute epoxy. The sandwich with jute epoxy skin deforms approximately 1.6 times more than that of same geometry of sandwich with glass epoxy skin. Thus exhibiting its elastic nature and making it potential candidate for low velocity impact application.

  8. Low Velocity Zones along the San Jacinto Fault, Southern California, inferred from Local Earthquakes

    Science.gov (United States)

    Li, Z.; Yang, H.; Peng, Z.; Ben-Zion, Y.; Vernon, F.

    2013-12-01

    Natural fault zones have regions of brittle damage leading to a low-velocity zone (LVZ) in the immediate vicinity of the main fault interface. The LVZ may amplify ground motion, modify rupture propagation, and impact derivation of earthquke properties. Here we image low-velocity fault zone structures along the San Jacinto Fault (SJF), southern California, using waveforms of local earthquakes that are recorded at several dense arrays across the SJFZ. We use generalized ray theory to compute synthetic travel times to track the direct and FZ-reflected waves bouncing from the FZ boundaries. This method can effectively reduce the trade-off between FZ width and velocity reduction relative to the host rock. Our preliminary results from travel time modeling show the clear signature of LVZs along the SJF, including the segment of the Anza seismic gap. At the southern part near the trifrication area, the LVZ of the Clark Valley branch (array JF) has a width of ~200 m with ~55% reduction in Vp and Vs. This is consistent with what have been suggested from previous studies. In comparison, we find that the velocity reduction relative to the host rock across the Anza seismic gap (array RA) is ~50% for both Vp and Vs, nearly as prominent as that on the southern branches. The width of the LVZ is ~230 m. In addition, the LVZ across the Anza gap appears to locate in the northeast side of the RA array, implying potential preferred propagation direction of past ruptures.

  9. Low-velocity impact damage of woven fabric composites: Finite element simulation and experimental verification

    International Nuclear Information System (INIS)

    Hassan, M.A.; Naderi, S.; Bushroa, A.R.

    2014-01-01

    Highlights: • Low-velocity impact test on GFRP with different energy levels and thicknesses. • Using force–deflection curve to determine critical energy for penetration threshold. • Reflection of damage processes to different type of diagrams. • Significant influence of Initial energy and thickness on dynamic response of plates. • Good agreements between experimental and FEM models for the force history data. - Abstract: This paper addresses the response of Glass Fiber Reinforced Plastic laminates (GFRPs) under low-velocity impact. Experimental tests were performed according to ASTM: D5628 for different initial impact energy levels ranging from 9.8 J to 29.4 J and specimen thicknesses of 2, 3 and 4 mm. The impact damage process and contact stiffness were studied incrementally until a perforation phase of the layered compounds occurred, in line with a force–deflection diagram and imaging of impacted laminates. The influence that impact parameters such as velocity and initial energy had on deflection and damage of the test specimens was investigated. Finite Element Simulation (FES) was done using MSC. MARC® was additionally carried out to understand the impact mechanism and correlation between these parameters and the induced damage. The simulation and experimental results reached good accord regarding maximum contact force and contact time with insignificant amount of damage

  10. Atomic collision experiments utilizing low-velocity, highly-charged ion beams

    International Nuclear Information System (INIS)

    Johnson, B.M.; Jones, K.W.; Meron, M.

    1983-01-01

    Intense beams of highly-stripped ions are now routinely produced at low velocities using the Brookhaven dual MP-tandems in a unique four-stage accel/decel mode. This mode of operation combines three stages of acceleration, stripping at high energy, and one stage of deceleration to near-zero velocity. To date, experiments have used 10-100 nA beams of bare and few-electron heavy ions at energies as low as 0.2 MeV/amu, and upgrades of the facility should push the lower limit below 0.1 MeV/amu. Recent experiments, such as measurements of charge transfer and x-ray production for S 6 - 16 + on He and Ar at 6-20 MeV and P(b) measurements for MO x-rays produced in Cl 16 + + Ar collisions at 20, 10 and 5 MeV have demonstrated the usefulness of highly-stripped, low-velocity projectiles. These experiments and a few possibilities for future experiments are discussed

  11. Resolution of low-velocity control in golf putting differentiates professionals from amateurs.

    Science.gov (United States)

    Hasegawa, Yumiko; Fujii, Keisuke; Miura, Akito; Yamamoto, Yuji

    2017-07-01

    It is difficult for humans to apply small amounts of force precisely during motor control. However, experts who have undergone extended training are thought to be able to control low-velocity movement with precision. We investigated the resolution of motor control in golf putting. A total of 10 professional and 10 high-level amateur golfers participated. Putting distances were 0.6-3.3 m, in increments of 0.3 m. We measured the impact velocity and the club-face angle at impact, and the acceleration profile of the downswing. The professionals showed significantly smaller coefficients of variation with respect to impact velocity and smaller root mean square errors in relation to acceleration profiles than did the amateurs. To examine the resolution of motor control for impact velocity, we investigated intra-participant differences in the impact velocity of the club head at two adjacent distances. We found that professionals had higher velocity precision when putting small distance intervals than did amateurs. That is, professionals had higher resolution of low-velocity control than did high-level amateurs. Our results suggest that outstanding performance at a task involves the ability to recognise small distinctions and to produce appropriate movements.

  12. Comparison of positronium, positron and electron collisions with hydrogen at low velocities

    International Nuclear Information System (INIS)

    Reeth, P Van; Humberston, J W; Woods, Denton; Ward, S J

    2016-01-01

    Recent experimental findings indicate that at equal velocity electron and ortho-positronium scattering cross sections are similar over a wide range of velocities and targets where both elastic and inelastic processes can take place. We present a comparative study of positronium, positron and electron elastic scattering from atomic hydrogen in order to investigate if a similar behaviour occurs for this target at low velocities where inelastic channels are closed. We calculate elastic cross sections for the three projectiles using Kohn-type variational methods which allows us to make a detailed study of the differences and similarities. We find a qualitative similarity in the spin-weighted elastic integrated cross sections for positronium and electron scattering and a good agreement between the singlet integrated cross sections. However, this agreement does extend to the low velocity region and where the agreement is found in the integrated cross sections we show that it is not present in the individual partial waves cross sections. Interestingly, given the agreement we find in the singlet integrated cross section for electron and positronium scattering, when comparing the overall shapes of the corresponding singlet differential cross sections we find different angular and velocity dependencies. (paper)

  13. Low-velocity Impact Response of a Nanocomposite Beam Using an Analytical Model

    Directory of Open Access Journals (Sweden)

    Mahdi Heydari Meybodi

    Full Text Available AbstractLow-velocity impact of a nanocomposite beam made of glass/epoxy reinforced with multi-wall carbon nanotubes and clay nanoparticles is investigated in this study. Exerting modified rule of mixture (MROM, the mechanical properties of nanocomposite including matrix, nanoparticles or multi-wall carbon nanotubes (MWCNT, and fiber are attained. In order to analyze the low-velocity impact, Euler-Bernoulli beam theory and Hertz's contact law are simultaneously employed to govern the equations of motion. Using Ritz's variational approximation method, a set of nonlinear equations in time domain are obtained, which are solved using a fourth order Runge-Kutta method. The effect of different parameters such as adding nanoparticles or MWCNT's on maximum contact force and energy absorption, stacking sequence, geometrical dimensions (i.e., length, width and height, and initial velocity of the impactor have been studied comprehensively on dynamic behavior of the nanocomposite beam. In addition, the result of analytical model is compared with Finite Element Modeling (FEM.The results reveal that the effect of nanoparticles on energy absorption is more considerable at higher impact energies.

  14. Atomic collision experiments utilizing low-velocity, highly-charged ion beams

    International Nuclear Information System (INIS)

    Johnson, B.M.; Jones, K.W.; Meron, M.

    1982-01-01

    Intense beams of highly-stripped ions are now routinely produced at low velocities using the Brookhaven dual MP-tandens in a unique four-stage accel/decel mode. This mode of operation combines three stages of acceleration, stripping at high energy, and one stage of deceleration to near-zero velocity. To date, experiments have used 10-100 nA beams of bare and few-electron heavy ions at energies as low as 0.2 MeV/amu, and upgrades of the facility should push the lower limit below 0.1 MeV/amu. Recent experiments, such as measurements of charge transfer and x-ray production for S/sup 6-16+/ on He and Ar at 6 to 20 MeV and P(b) measurements for MO x-rays produced in Cl 16 + + Ar collisions at 20, 10, and 5 MeV have demonstrated the usefulness of highly-stripped, low-velocity projectiles. These experiments and a few possibilities for future experiments are discussed

  15. Research on carbon fiber–reinforced plastic bumper beam subjected to low-velocity frontal impact

    Directory of Open Access Journals (Sweden)

    Yefa Hu

    2015-06-01

    Full Text Available Lightweight and safety performance of automobiles are two important factors for automobile designs. In this article, a research on lightweight and crashworthiness of automotive bumper has been conducted. The carbon fiber–reinforced plastic bumper beam is considered to replace the traditional high-strength steel one. The low-velocity impact finite element simulations for the above two bumper beams are performed via LS-DYNA. Furthermore, the energy absorption capabilities and dynamic response characteristics of the carbon fiber–reinforced plastic bumper beam are investigated and compared with the steel one. The results show that the carbon fiber–reinforced plastic bumper beam is of the better energy absorption capabilities and dynamic response characteristics than those of the steel one; the weight has decreased remarkably close to 50%. Meanwhile, the effect of lay-up and wall thickness on the crashworthiness of the carbon fiber–reinforced plastic bumper beam under low-velocity impact is also studied in this article to select appropriate design schemes.

  16. Holonomy anomalies

    International Nuclear Information System (INIS)

    Bagger, J.; Nemeschansky, D.; Yankielowicz, S.

    1985-05-01

    A new type of anomaly is discussed that afflicts certain non-linear sigma models with fermions. This anomaly is similar to the ordinary gauge and gravitational anomalies since it reflects a topological obstruction to the reparametrization invariance of the quantum effective action. Nonlinear sigma models are constructed based on homogeneous spaces G/H. Anomalies arising when the fermions are chiral are shown to be cancelled sometimes by Chern-Simons terms. Nonlinear sigma models are considered based on general Riemannian manifolds. 9 refs

  17. Time dependent response of low velocity impact induced composite conical shells under multiple delamination

    Science.gov (United States)

    Dey, Sudip; Karmakar, Amit

    2014-02-01

    This paper presents the time dependent response of multiple delaminated angle-ply composite pretwisted conical shells subjected to low velocity normal impact. The finite element formulation is based on Mindlin's theory incorporating rotary inertia and effects of transverse shear deformation. An eight-noded isoparametric plate bending element is employed to satisfy the compatibility of deformation and equilibrium of resultant forces and moments at the delamination crack front. A multipoint constraint algorithm is incorporated which leads to asymmetric stiffness matrices. The modified Hertzian contact law which accounts for permanent indentation is utilized to compute the contact force, and the time dependent equations are solved by Newmark's time integration algorithm. Parametric studies are conducted with respect to triggering parameters like laminate configuration, location of delamination, angle of twist, velocity of impactor, and impactor's displacement for centrally impacted shells.

  18. Modified method of perturbed stationary states. II. Semiclassical and low-velocity quantal approximations

    International Nuclear Information System (INIS)

    Green, T.A.

    1978-10-01

    For one-electron heteropolar systems, the wave-theoretic Lagrangian of Paper I 2 is simplified in two distinct approximations. The first is semiclassical; the second is quantal, for velocities below those for which the semiclassical treatment is reliable. For each approximation, unitarity and detailed balancing are discussed. Then, the variational method as described by Demkov is used to determine the coupled equations for the radial functions and the Euler-Lagrange equations for the translational factors which are part of the theory. Specific semiclassical formulae for the translational factors are given in a many-state approximation. Low-velocity quantal formulae are obtained in a one-state approximation. The one-state results of both approximations agree with an earlier determination by Riley. 14 references

  19. Study of low-velocity impact response of sandwich panels with shear-thickening gel cores

    Science.gov (United States)

    Wang, Yunpeng; Gong, Xinglong; Xuan, Shouhu

    2018-06-01

    The low-velocity impact response of sandwich panels with shear-thickening gel cores was studied. The impact tests indicated that the sandwich panels with shear-thickening gel cores showed excellent properties of energy dissipation and stress distribution. In comparison to the similar sandwich panels with chloroprene rubber cores and ethylene-propylene-diene monomer cores, the shear-thickening gel cores led to the obviously smaller contact forces and the larger energy absorptions. Numerical modelling with finite element analysis was used to investigate the stress distribution of the sandwich panels with shear-thickening gel cores and the results agreed well with the experimental results. Because of the unique mechanical property of the shear-thickening gel, the concentrated stress on the front facesheets were distributed to larger areas on the back facesheets and the peak stresses were reduced greatly.

  20. Low velocity instrumented impact testing of four new damage tolerant carbon/epoxy composite systems

    Science.gov (United States)

    Lance, D. G.; Nettles, A. T.

    1990-01-01

    Low velocity drop weight instrumented impact testing was utilized to examine the damage resistance of four recently developed carbon fiber/epoxy resin systems. A fifth material, T300/934, for which a large data base exists, was also tested for comparison purposes. A 16-ply quasi-isotropic lay-up configuration was used for all the specimens. Force/absorbed energy-time plots were generated for each impact test. The specimens were cross-sectionally analyzed to record the damage corresponding to each impact energy level. Maximum force of impact versus impact energy plots were constructed to compare the various systems for impact damage resistance. Results show that the four new damage tolerant fiber/resin systems far outclassed the T300/934 material. The most damage tolerant material tested was the IM7/1962 fiber/resin system.

  1. Numerical and Experimental Low-Velocity Impact Behaivor of Sandwich Plates with Viscoelastic Core

    Directory of Open Access Journals (Sweden)

    Soroush Sadeghnejad

    2016-03-01

    Full Text Available A numerical and experimental low-velocity impact behavior of sandwich plates have been presently studied with regard to the compressibility and viscoelasticity features of their cores. Face sheets were assumed to be anisotropic composites or isotropic aluminum materials and a viscoelastic behavior has been considered for core. The boundary conditions are assumed to be simply supported or rigid. Abaqus, as FEM software, and its python script programming feature, have been used to model the specimens. To model hyper-viscoelastic nonlinear behavior of the core, Ogden hyper-foam elasticity and Prony series approach are manipulated. To solve the numerical problem, dynamic explicit solver option with sufficient solving amplitude has been used. Prony series have been used to model the core time-dependent behavior. In conjunction with a simple indentation experiment, FEM used to formulate a novel method for finding the Prony series coefficients. By performing some low-velocity impact experiments, the impact force and displacement of the composite sandwich plates have been investigated. The results indicate that increasing the structural damping increases the contact time and missing energy and decreases the stored energy of the system. The structures with composite face sheets have a minimum ratio of upper face sheet displacement to lower face sheet displacement in comparison to those with the isotropic face sheets. Impact behavior of isotropic face sheet specimens are more flattened than that of the composite face sheets. In addition, the specific energy stored in the sandwich plates with composite face sheets, on different supports, is greater than that stored in the aluminum face sheets.

  2. Management and outcome of low velocity penetrating head injury caused by impacted foreign bodies.

    Science.gov (United States)

    Moussa, Wael Mohamed Mohamed; Abbas, Mohamed

    2016-05-01

    Penetrating head injuries with impacted foreign bodies are rare, associated with a high incidence of morbidity and potentially life-threatening. In this study, we aimed at investigating the outcome of these cases as well as analyzing the factors affecting the prognosis. A retrospective study in which the records of 16 patients who had penetrating head injuries caused by low-velocity impacted foreign bodies were revised. All patients were males with a mean age of 28.9 years (range, 18 to 50 years). The follow-up period ranged from 4 to 13 months with a mean of 8.1 months. Causes of injury were construction accidents in 6 (37.5 %) patients, assault in 6 (37.5 %) and road traffic accidents in 4 (25 %). The impacted objects included a bar of iron, a piece of wood, a nail, a sickle and a piece of glass. Diagnostic computerized tomography (CT) of the brain was carried out on admission in all patients. Thirteen (81.3 %) patients were submitted to surgery, and all had the appropriate management in the form of antibiotics and dehydrating measures as required. The primary outcome measure was the Glasgow Outcome Scale (GOS) at the end of follow-up. At the end of follow-up, ten (62.5 %) patients had a GOS score of 5, two (12.5 %) patients had a score of 4, and four (25 %) patients had a score of 1. Low-velocity penetrating head injuries are most common in young adult males. With the appropriate management, a majority of even the most severe cases can have a favorable outcome.

  3. Summary and evaluation of low-velocity impact tests of solid steel billet onto concrete pads

    International Nuclear Information System (INIS)

    Witte, M.C.; Hovingh, W.J.; Mok, G.C.; Murty, S.S.; Chen, T.F.; Fischer, L.E.

    1998-02-01

    Spent fuel storage casks intended for use at independent spent fuel storage installations are evaluated during the application and review process for low-velocity impacts representative of possible handling accidents. In the past, the analyses involved in these evaluations have assumed that the casks dropped or tipped onto an unyielding surface - a conservative and simplifying assumption. Since 10 CFR Part 72, the regulation imposed by the Nuclear Regulatory Commission (NRC), does not require this assumption, applicants are currently seeking a more realistic model for the analyses to predict the effect of a cask dropping onto a reinforced concrete pad, including energy absorbing aspects such as cracking and flexure. To develop data suitable for benchmarking these analyses, the NRC has conducted several series of drop-test studies of a solid steel billet and of a near-full-scale empty cask. This report contains a summary and evaluation of all steel billet testing conducted by Sandia National Laboratories and Lawrence Livermore National Laboratory. A series of finite element analyses of the billet testing is described and benchmarked against the test data. A method to apply the benchmarked finite element model of the soil and concrete pad to an analysis of a full-size storage cask is provided. In addition, an application to a open-quotes genericclose quotes full-size cask is presented for side and end drops, and tipover events. The primary purpose of this report is to provide applicants for an NRC license under 10 CFR Part 72 with a method for evaluating storage casks for low-velocity impact conditions

  4. Effect of low velocity impact damage on the natural frequency of composite plates

    Science.gov (United States)

    Chok, E. Y. L.; Majid, D. L. A. A.; Harmin, M. Y.

    2017-12-01

    Biodegradable natural fibers have been suggested to replace the hazardous synthetic fibers in many aerospace applications. However, this notion has been limited due to their low mechanical properties, which leads to the idea of hybridizing the two materials. Many aircraft components such as radome, aft body and wing are highly susceptible to low velocity impact damage while in-service. The damages degrade the structural integrity of the components and change their dynamic characteristics. In worst case scenario, the changes can lead to resonance, which is an excessive vibration. This research is conducted to study the dynamic characteristic changes of low velocity impact damaged hybrid composites that is designed for aircraft radome applications. Three materials, which are glass fiber, kenaf fiber and kenaf/glass fiber hybrid composites, have been impacted with 3J, 6J and 9J of energy. Cantilevered and also vertically clamped boundary conditions are used and the natural frequencies are extracted for each of the specimens. The obtained results show that natural frequency decreases with increasing impact level. Cantilevered condition is found to induce lower modes due to the gravitational pull. To eliminate mass and geometrical effects, normalized modes are computed. Among the three materials considered, glass fiber composites have displayed the highest normalized frequency that reflects on its higher stiffness compared to the other two materials. As the damage level is increased, glass fiber composites have shown the highest frequency reduction to a maximum of 35% while kenaf composites have the least frequency reduction in the range of 1 - 18%. Thus, kenaf fiber is taken to be helpful in stalling the damage progression and reducing the effect of damage. This has been proven when the percentage frequency decrement shown by kenaf/glass fiber composite lies between glass fiber and kenaf fiber composites.

  5. Superconducting low-velocity linac for the Argonne positive-ion injector

    International Nuclear Information System (INIS)

    Shepard, K.W.; Markovich, P.K.; Zinkann, G.P.; Clifft, B.; Benaroya, R.

    1989-01-01

    A low-velocity superconducting linac has been developed as part of a positive-ion injector system, which is replacing a 9 MV tandem as the injector for the ATLAS accelerator. The linac consists of an independently phased array of resonators, and is designed to accelerate various ions over a velocity range .008 < v/c < .06. The resonator array is formed of four different types of superconducting interdigital structures. The linac is being constructed in three phases, each of which will cover the full velocity range. Successive phases will increase the total accelerating potential and permit heavier ions to be accelerated. Assembly of the first phase was completed in early 1989. In initial tests with beam, a five-resonator array provided approximately 3.5 MV of accelerating potential and operated without difficulty for several hundred hours. The second phase is scheduled for completion in late 1989, and will increase the accelerating potential to more than 8 MV. 5 refs., 2 figs., 1 tab

  6. Low-Velocity Impact Behavior of Sandwich Structures with Additively Manufactured Polymer Lattice Cores

    Science.gov (United States)

    Turner, Andrew J.; Al Rifaie, Mohammed; Mian, Ahsan; Srinivasan, Raghavan

    2018-05-01

    Sandwich panel structures are widely used in aerospace, marine, and automotive applications because of their high flexural stiffness, strength-to-weight ratio, good vibration damping, and low through-thickness thermal conductivity. These structures consist of solid face sheets and low-density cellular core structures, which are traditionally based upon honeycomb folded-sheet topologies. The recent advances in additive manufacturing (AM) or 3D printing process allow lattice core configurations to be designed with improved mechanical properties. In this work, the sandwich core is comprised of lattice truss structures (LTS). Two different LTS designs are 3D-printed using acrylonitrile butadiene styrene (ABS) and are tested under low-velocity impact loads. The absorption energy and the failure mechanisms of lattice cells under such loads are investigated. The differences in energy-absorption capabilities are captured by integrating the load-displacement curve found from the impact response. It is observed that selective placement of vertical support struts in the unit-cell results in an increase in the absorption energy of the sandwich panels.

  7. Hearthfire design base for the high current low velocity rf linac

    International Nuclear Information System (INIS)

    Burke, R.J.; Khoe, T.K.; Kustom, R.L.; Martin, R.L.; Moretti, A.

    1977-01-01

    The particle beam parameters needed for inertial fusion can be achieved with conventional accelerator technology if heavy ion machines attain the level of performance of the most intense high energy proton machines. Many of the problems posed by this goal pertain to the low energy portions of the accelerator system. In particular, the implied particle current in the rf linac is 10 3 --10 4 times the values achieved with existing heavy ion machines. Much of this discrepancy is simply attributable to the great differences between the design considerations relevant to accelerators for fusion and those which have determined the performance of the existing machines. The basic concept chosen at Argonne National Laboratory is cavities containing single drift tubes mounted on lambda/4 supports. Such structures pose the least problem for the beam transport system, and one cavity is placed between adjacent quadrupole magnets. The average voltage gain of the first cells of the low velocity section is moderate; and, although probably acceptable and improved by the end of the 10 MV section, the low initial gain adds to the motivation provided by the transport problem to increase the preinjector voltage substantially above 750 kV

  8. Verification and Validation of Carbon-Fiber Laminate Low Velocity Impact Simulations.

    Energy Technology Data Exchange (ETDEWEB)

    English, Shawn Allen; Nelson, Stacy Michelle; Briggs, Timothy; Brown, Arthur A.

    2014-10-01

    Presented is a model verification and validation effort using low - velocity impact (LVI) of carbon fiber reinforced polymer laminate experiments. A flat cylindrical indenter impacts the laminate with enough energy to produce delamination, matrix cracks and fiber breaks. Included in the experimental efforts are ultrasonic scans of the damage for qualitative validation of the models. However, the primary quantitative metrics of validation are the force time history measured through the instrumented indenter and initial and final velocities. The simulations, whi ch are run on Sandia's Sierra finite element codes , consist of all physics and material parameters of importance as determined by a sensitivity analysis conducted on the LVI simulation. A novel orthotropic damage and failure constitutive model that is cap able of predicting progressive composite damage and failure is described in detail and material properties are measured, estimated from micromechanics or optimized through calibration. A thorough verification and calibration to the accompanying experiment s are presented. Specia l emphasis is given to the four - point bend experiment. For all simulations of interest, the mesh and material behavior is verified through extensive convergence studies. An ensemble of simulations incorporating model parameter unc ertainties is used to predict a response distribution which is then compared to experimental output. The result is a quantifiable confidence in material characterization and model physics when simulating this phenomenon in structures of interest.

  9. On the Behavior of Fiberglass Epoxy Composites under Low Velocity Impact Loading

    Directory of Open Access Journals (Sweden)

    Gautam S. Chandekar

    2010-01-01

    Full Text Available Response of fiberglass epoxy composite laminates under low velocity impact loading is investigated using LS-DYNA®, and the results are compared with experimental analysis performed using an instrumented impact test setup (Instron dynatup 8250. The composite laminates are manufactured using H-VARTM© process with basket weave E-Glass fabrics. Epon 862 is used as a resin system and Epicure-W as a hardening agent. Composite laminates, with 10 layers of fiberglass fabrics, are modeled using 3D solid elements in a mosaic fashion to represent basket weave pattern. Mechanical properties are calculated by using classical micromechanical theory and assigned to the elements using ORTHOTROPIC ELASTIC material model. The damage occurred since increasing impact energy is incorporated using ADVANCED COMPOSITE DAMAGE material model in LS-DYNA®. Good agreements are obtained with the failure damage results in LS-DYNA® and experimental results. Main considerations for comparison are given to the impact load carrying capacity and the amount of impact energy absorbed by the laminates.

  10. Measurement of fast-changing low velocities by photonic Doppler velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Song Hongwei; Wu Xianqian; Huang Chenguang; Wei Yangpeng; Wang Xi [Key Laboratory for Hydrodynamics and Ocean Engineering, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China)

    2012-07-15

    Despite the increasing popularity of photonic Doppler velocimetry (PDV) in shock wave experiments, its capability of capturing low particle velocities while changing rapidly is still questionable. The paper discusses the performance of short time Fourier transform (STFT) and continuous wavelet transform (CWT) in processing fringe signals of fast-changing low velocities measured by PDV. Two typical experiments are carried out to evaluate the performance. In the laser shock peening test, the CWT gives a better interpretation to the free surface velocity history, where the elastic precursor, main plastic wave, and elastic release wave can be clearly identified. The velocities of stress waves, Hugoniot elastic limit, and the amplitude of shock pressure induced by laser can be obtained from the measurement. In the Kolsky-bar based tests, both methods show validity of processing the longitudinal velocity signal of incident bar, whereas CWT improperly interprets the radial velocity of the shocked sample at the beginning period, indicating the sensitiveness of the CWT to the background noise. STFT is relatively robust in extracting waveforms of low signal-to-noise ratio. Data processing method greatly affects the temporal resolution and velocity resolution of a given fringe signal, usually CWT demonstrates a better local temporal resolution and velocity resolution, due to its adaptability to the local frequency, also due to the finer time-frequency product according to the uncertainty principle.

  11. Low-Velocity Impact Behavior of Sandwich Structures with Additively Manufactured Polymer Lattice Cores

    Science.gov (United States)

    Turner, Andrew J.; Al Rifaie, Mohammed; Mian, Ahsan; Srinivasan, Raghavan

    2018-04-01

    Sandwich panel structures are widely used in aerospace, marine, and automotive applications because of their high flexural stiffness, strength-to-weight ratio, good vibration damping, and low through-thickness thermal conductivity. These structures consist of solid face sheets and low-density cellular core structures, which are traditionally based upon honeycomb folded-sheet topologies. The recent advances in additive manufacturing (AM) or 3D printing process allow lattice core configurations to be designed with improved mechanical properties. In this work, the sandwich core is comprised of lattice truss structures (LTS). Two different LTS designs are 3D-printed using acrylonitrile butadiene styrene (ABS) and are tested under low-velocity impact loads. The absorption energy and the failure mechanisms of lattice cells under such loads are investigated. The differences in energy-absorption capabilities are captured by integrating the load-displacement curve found from the impact response. It is observed that selective placement of vertical support struts in the unit-cell results in an increase in the absorption energy of the sandwich panels.

  12. Superconducting low-velocity linac for the Argonne positive-ion injector

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.; Markovich, P.K.; Zinkann, G.P.; Clifft, B.; Benaroya, R.

    1989-01-01

    A low-velocity superconducting linac has been developed as part of a positive-ion injector system, which is replacing a 9 MV tandem as the injector for the ATLAS accelerator. The linac consists of an independently phased array of resonators, and is designed to accelerate various ions over a velocity range .008 < v/c < .06. The resonator array is formed of four different types of superconducting interdigital structures. The linac is being constructed in three phases, each of which will cover the full velocity range. Successive phases will increase the total accelerating potential and permit heavier ions to be accelerated. Assembly of the first phase was completed in early 1989. In initial tests with beam, a five-resonator array provided approximately 3.5 MV of accelerating potential and operated without difficulty for several hundred hours. The second phase is scheduled for completion in late 1989, and will increase the accelerating potential to more than 8 MV. 5 refs., 2 figs., 1 tab.

  13. Effect of temperature on composite sandwich structures subjected to low velocity impact. [aircraft construction materials

    Science.gov (United States)

    Sharma, A. V.

    1980-01-01

    The effect of low velocity projectile impact on sandwich-type structural components was investigated. The materials used in the fabrication of the impact surface were graphite-, Kevlar-, and boron-fibers with appropriate epoxy matrices. The testing of the specimens was performed at moderately low- and high-temperatures as well as at room temperature to assess the impact-initiated strength degradation of the laminates. Eleven laminates with different stacking sequences, orientations, and thicknesses were tested. The low energy projectile impact is considered to simulate the damage caused by runway debris, the dropping of the hand tools during servicing, etc., on the secondary aircraft structures fabricated with the composite materials. The results show the preload and the impact energy combinations necessary to cause catastrophic failure in the laminates tested. A set of faired curves indicating the failure thresholds is shown separately for the tension-and compression-loaded laminates. The specific-strengths and -modulii for the various laminates tested are also given.

  14. Anomaly mediation deformed by axion

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, Kazunori, E-mail: kazunori@hep-th.phys.s.u-tokyo.ac.jp [Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa 277-8583 (Japan); Yanagida, Tsutomu T. [Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa 277-8583 (Japan)

    2013-05-13

    We show that in supersymmetric axion models the axion supermultiplet obtains a sizable F-term due to a non-supersymmetric dynamics and it generally gives the gaugino masses comparable to the anomaly mediation contribution. Thus the gaugino mass relation predicted by the anomaly mediation effect can be significantly modified in the presence of axion to solve the strong CP problem.

  15. Evaluation of mechanical properties and low velocity impact characteristics of balsa wood and urethane foam applied to impact limiter of nuclear spent fuel shipping cask

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Junsung; Shin, Kwangbok [Hanbat Nat' l Univ., Daejeon (Korea, Republic of); Choi, Woosuk [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-11-15

    The paper aims to evaluate the low velocity impact responses and mechanical properties of balsa wood and urethane foam core materials and their sandwich panels, which are applied as the impact limiter of a nuclear spent fuel shipping cask. For the urethane foam core, which is isotropic, tensile, compressive, and shear mechanical tests were conducted. For the balsa wood core, which is orthotropic and shows different material properties in different orthogonal directions, nine mechanical properties were determined. The impact test specimens for the core material and their sandwich panel were subjected to low velocity impact loads using an instrumented testing machine at impact energy levels of 1, 3, and 5J. The experimental results showed that both the urethane foam and the balsa wood core except in the growth direction (z-direction) had a similar impact response for the energy absorbing capacity, contact force, and indentation. Furthermore, it was found that the urethane foam core was suitable as an impact limiter material owing to its resistance to fire and low cost, and the balsa wood core could also be strongly considered as an impact limiter material for a lightweight nuclear spent fuel shipping cask.

  16. Mapping Deep Low Velocity Zones in Alaskan Arctic Coastal Permafrost using Seismic Surface Waves

    Science.gov (United States)

    Dou, S.; Ajo Franklin, J. B.; Dreger, D. S.

    2012-12-01

    Permafrost degradation may be an important amplifier of climate change; Thawing of near-surface sediments holds the potential of increasing greenhouse gas emissions due to microbial decomposition of preserved organic carbon. Recently, the characterization of "deep" carbon pools (several meters below the surface) in circumpolar frozen ground has increased the estimated amount of soil carbon to three times higher than what was previously thought. It is therefore potentially important to include the characteristics and processes of deeper permafrost strata (on the orders of a few to tens of meters below surface) in climate models for improving future predictions of accessible carbon and climate feedbacks. This extension is particularly relevant if deeper formations are not completely frozen and may harbor on-going microbial activity despite sub-zero temperatures. Unfortunately, the characterization of deep permafrost systems is non-trivial; logistics and drilling constraints often limit direct characterization to relatively shallow units. Geophysical measurements, either surface or airborne, are often the most effective tools for evaluating these regions. Of the available geophysical techniques, the analysis of seismic surface waves (e.g. MASW) has several unique advantages, mainly the ability to provide field-scale information with good depth resolution as well as penetration (10s to 100s of m with small portable sources). Surface wave methods are also able to resolve low velocity regions, a class of features that is difficult to characterize using traditional P-wave refraction methods. As part of the Department of Energy (DOE) Next-Generation Ecosystem Experiments (NGEE-Arctic) project, we conducted a three-day seismic field survey (May 12 - 14, 2012) at the Barrow Environmental Observatory, which is located within the Alaskan Arctic Coastal Plain. Even though permafrost at the study site is continuous, ice-rich and thick (>= 350m), our Multichannel Analysis of

  17. Low Risk Anomalies?

    DEFF Research Database (Denmark)

    Schneider, Paul; Wagner, Christian; Zechner, Josef

    . Empirically, we find that option-implied ex-ante skewness is strongly related to ex-post residual coskewness and alphas. Beta- and volatility-based low risk anomalies are largely driven by a single principal component, which is in turn largely explained by skewness. Controlling for skewness renders the alphas......This paper shows that stocks' CAPM alphas are negatively related to CAPM betas if investors demand compensation for negative skewness. Thus, high (low) beta stocks appear to underperform (outperform). This apparent anomaly merely reflects compensation for residual coskewness ignored by the CAPM...... of betting-against-beta and -volatility insignificant....

  18. Numerical simulating and experimental study on the woven carbon fiber-reinforced composite laminates under low-velocity impact

    Science.gov (United States)

    Liu, Hanyang; Tang, Zhanwen; Pan, Lingying; Zhao, Weidong; Sun, Baogang; Jiang, Wenge

    2016-05-01

    Impact damage has been identified as a critical form of the defects that constantly threatened the reliability of composite structures, such as those used in the aerospace structures and systems. Low energy impacts can introduce barely visible damage and cause the degradation of structural stiffness, furthermore, the flaws caused by low-velocity impact are so dangerous that they can give rise to the further extended delaminations. In order to improve the reliability and load carrying capacity of composite laminates under low-velocity impact, in this paper, the numerical simulatings and experimental studies on the woven fiber-reinforced composite laminates under low-velocity impact with impact energy 16.7J were discussed. The low velocity impact experiment was carried out through drop-weight system as the reason of inertia effect. A numerical progressive damage model was provided, in which the damages of fiber, matrix and interlamina were considered by VUMT subroutine in ABAQUS, to determine the damage modes. The Hashin failure criteria were improved to cover the failure modes of fiber failure in the directions of warp/weft and delaminations. The results of Finite Element Analysis (FEA) were compared with the experimental results of nondestructive examination including the results of ultrasonic C-scan, cross-section stereomicroscope and contact force - time history curves. It is found that the response of laminates under low-velocity impact could be divided into stages with different damage. Before the max-deformation of the laminates occurring, the matrix cracking, fiber breakage and delaminations were simulated during the impactor dropping. During the releasing and rebounding period, matrix cracking and delaminations areas kept increasing in the laminates because of the stress releasing of laminates. Finally, the simulating results showed the good agreements with the results of experiment.

  19. DOWN'S ANOMALY.

    Science.gov (United States)

    PENROSE, L.S.; SMITH, G.F.

    BOTH CLINICAL AND PATHOLOGICAL ASPECTS AND MATHEMATICAL ELABORATIONS OF DOWN'S ANOMALY, KNOWN ALSO AS MONGOLISM, ARE PRESENTED IN THIS REFERENCE MANUAL FOR PROFESSIONAL PERSONNEL. INFORMATION PROVIDED CONCERNS (1) HISTORICAL STUDIES, (2) PHYSICAL SIGNS, (3) BONES AND MUSCLES, (4) MENTAL DEVELOPMENT, (5) DERMATOGLYPHS, (6) HEMATOLOGY, (7)…

  20. Classification of Low Velocity Impactors Using Spiral Sensing of Acousto-Ultrasonic Waves

    Science.gov (United States)

    Agbasi, Chijioke Raphael

    The non-linear elastodynamics of a flat plate subjected to low velocity foreign body impacts is studied, resembling the space debris impacts on the space structure. The work is based on a central hypothesis that in addition to identifying the impact locations, the material properties of the foreign objects can also be classified using acousto-ultrasonic signals (AUS). Simultaneous localization of impact point and classification of impact object is quite challenging using existing state-of-the-art structural health monitoring (SHM) approaches. Available techniques seek to report the exact location of impact on the structure, however, the reported information is likely to have errors from nonlinearity and variability in the AUS signals due to materials, geometry, boundary conditions, wave dispersion, environmental conditions, sensor and hardware calibration etc. It is found that the frequency and speed of the guided wave generated in the plate can be quantized based on the impactor's relationship with the plate (i.e. the wave speed and the impactor's mechanical properties are coupled). In this work, in order to characterize the impact location and mechanical properties of imapctors, nonlinear transient phenomenon is empirically studied to decouple the understanding using the dominant frequency band (DFB) and Lag Index (LI) of the acousto-ultrasonic signals. Next the understanding was correlated with the elastic modulus of the impactor to predict transmitted force histories. The proposed method presented in this thesis is especially applicable for SHM where sensors cannot be widely or randomly distributed. Thus a strategic organization and localization of the sensors is achieved by implementing the geometric configuration of Theodorous Spiral Sensor Cluster (TSSC). The performance of TSSC in characterizing the impactor types are compared with other conventional sensor clusters (e.g. square, circular, random etc.) and it is shown that the TSSC is advantageous over

  1. Analysis of crustal thickness and off-axis low-velocity zones at the Endeavour segment of the Juan de Fuca Ridge

    Science.gov (United States)

    Wells, A. E.; Hooft, E. E.; Toomey, D. R.; Wilcock, W. S.; Weekly, R. T.

    2010-12-01

    is interpreted to have developed when the northwestward migrating Juan de Fuca Ridge overrode the mantle melt anomaly associated with the Heckle seamount chain. We investigate the segment-scale history of melt supply and the presence of off-axis crustal low-velocity zones using data from a multi-scale Endeavour seismic tomography experiment (ETOMO) that took place in September 2009. Seismic data were collected using four-component ocean bottom seismometers at 64 sites and the 6600 in3 airgun array of the R/V Marcus G. Langseth. The study includes 5567 shots covering 90 km along-axis and 50 km across. We examine seismic travel times of Pg and PmP phases as well as amplitude and waveform changes. Preliminary analysis of amplitude and waveform changes indicates that there are several crustal-level low-velocity, high-attenuation regions associated with off-axis ridges and volcanic features. We will determine whether there is enhanced melt supply due to the interaction between the Heckle seamount melting anomaly and the center of the Endeavour segment. We will also test whether volcano-tectonic cycles generate regions of thicker and thinner crust.

  2. The Effect of Temperature and Nanoclay on the Low Velocity and Ballistic Behavior of Woven Glass-Fiber Reinforced Composites

    Science.gov (United States)

    Patrin, Lauren

    The objective of this research was to study the effect of nanoclay and temperature on the behavior of woven glass-fabric reinforced epoxy composite under low velocity and ballistic impacts. The materials used in manufacturing the composite were S2 (6181) glass-fibers, epoxy resin (EPON 828), hardener (Epikure 3230), nanoclay and Heloxy 61 modifier. The nanoclay addition was 0%, 1%, 3% and 5% by weight, with respect to the resin. All specimens were manufactured at the City College facilities using vacuum infusion. Tensile tests were conducted to characterize the material and obtain the Young's modulus, ultimate stress, failure strain, Poisson's ratio, shear modulus and shear strength and their variation with nanoclay percentage and temperature. The tests were conducted at room temperature (21°C/70°F), -54°C (-65°F), -20°C (-4°F), 49°C (120°F) and 71°C (160°F). Next composite specimens with 0%, 1%, 3% and 5% nanoclay by weight, with respect to the resin, were subjected to low velocity impact at the previously specified temperatures to determine dynamic force, displacement and energy correlations. The extent of damage was studied using the ultrasound technique. Then ballistic tests were conducted on the nanoclay infused specimens at room temperature to obtain the ballistic limit (V50) and the damage behavior of the composite. The dynamic finite element analysis (FEA) software LS-DYNA was used to model and simulate the results of low velocity impact tests. Good agreement was obtained between experimental and numerical (FEA) results. Analytical analyses were undertaken to compare the results from the tensile experiments. The finite element analysis (FEA) allowed for further analytical comparison of the results. The FEA platform used was LS-DYNA due to its proficient dynamic and damage capabilities in composite materials. The FEA was used to model and simulate the low velocity impacts and compare the results to experiments.

  3. Low-velocity ion stopping in a dense and low-temperature plasma target

    Science.gov (United States)

    Deutsch, Claude; Popoff, Romain

    2007-07-01

    We investigate the stopping specificities involved in the heating of thin foils irradiated by intense ion beams in the 0.3-3 MeV/amu energy range and in close vicinity of the Bragg peak. Considering a swiftly ionized target to eV temperatures before expansion while retaining solid-state density, a typical warm dense matter (WDM) situation thus arises. We stress low Vp stopping through ion diffusion in the given target plasma. This allows to include the case of a strongly magnetized target in a guiding center approximation. We also demonstrate that the ion projectile penetration depth in target is significantly affected by multiple scattering on target electrons. The given plasma target is taken weakly coupled with Maxwell electron either with no magnetic field ( B=0) or strongly magnetized ( B≠0). Dynamical coupling between ion projectiles energy losses and projectiles charge state will also be addressed.

  4. Complex Seismic Anisotropy at the Edges of a Very-low Velocity Province in the Lowermost Mantle

    Science.gov (United States)

    Wang, Y.; Wen, L.

    2005-12-01

    A prominent very-low velocity province (VLVP) in the lowermost mantle is revealed, and has been extensively mapped out in recent seismic studies (e.g., Wang and Wen, 2004). Seismic evidence unambiguously indicates that the VLVP is compositionally distinct, and its seismic structure can be best explained by partial melting driven by a compositional change produced in the early Earth's history (Wen, 2001; Wen et. al, 2001; Wang and Wen, 2004). In this presentation, we study the seismic anisotropic behavior inside the VLVP and its surrounding area using SKS and SKKS waveform data. We collect 272 deep earthquakes recorded by more than 80 stations in the Kaapvaal seismic array in southern Africa from 1997 to 1999. Based on the data quality, we choose SKS and SKKS waveform data for 16 earthquakes to measure the anisotropic parameters: the fast polarization direction and the splitting time, using the method of Silver and Chan (1991). A total of 162 high-quality measurements are obtained based on the statistics analysis of shear wave splitting results. The obtained anisotropy exhibits different patterns for the SKS and SKKS phases sampling inside the VLVP and at the edges of the VLVP. When the SKS and SKKS phases sample inside the VLVP, their fast polarization directions exhibit a pattern that strongly correlates with stations, gradually changing from 11°N~to 80°N~across the seismic array from south to north and rotating back to the North direction over short distances for several northernmost stations. The anisotropy pattern obtained from the analysis of the SKKS phases is the same as that from the SKS phases. However, when the SKS and SKKS phases sample at the edges of the VLVP, the measured anisotropy exhibits a very complex pattern. The obtained fast polarization directions change rapidly over a small distance, and they no longer correlate with stations; the measurements obtained from the SKS analysis also differ with those from the SKKS analysis. As the SKS and SKKS

  5. Dyonic anomalies

    International Nuclear Information System (INIS)

    Henningson, Mans; Johansson, Erik P.G.

    2005-01-01

    We consider the problem of coupling a dyonic p-brane in d=2p+4 space-time dimensions to a prescribed (p+2)-form field strength. This is particularly subtle when p is odd. For the case p=1, we explicitly construct a coupling functional, which is a sum of two terms: one which is linear in the prescribed field strength, and one which describes the coupling of the brane to its self-field and takes the form of a Wess-Zumino term depending only on the embedding of the brane world-volume into space-time. We then show that this functional is well-defined only modulo a certain anomaly, related to the Euler class of the normal bundle of the brane world-volume

  6. Low velocity impact properties of intra-ply hybrid composites based on basalt and nylon woven fabrics

    International Nuclear Information System (INIS)

    Dehkordi, Majid Tehrani; Nosraty, Hooshang; Shokrieh, Mahmood Mehrdad; Minak, Giangiacomo; Ghelli, Daniele

    2010-01-01

    In this paper, the low velocity impact behavior of homogenous and hybrid composite laminates reinforced by basalt-nylon intra-ply fabrics was experimentally investigated. Epoxy resin was used as matrix material. The purpose of using this hybrid composite is to combine the good mechanical properties of basalt fiber with the excellent impact resistant of nylon fiber. Five different types of woven fabrics were used as reinforcement with different volume percentages of nylon (0%, 25%, 33.3%, 50% and 100%). The effect of nylon/basalt fiber content on maximum force, maximum deflection, residual deflection, total absorbed energy, elastic energy, size and type of damage were studied at several low velocity impact nominal energy levels (16, 30 and 40 J). The results indicate that impact performance of these composites is significantly affected by the nylon/basalt fiber content. The visual inspection and ultrasonic C-scan of the impact damaged specimens reveals that content of nylon/basalt fiber controls the type and size of damage.

  7. Dynamical properties for the problem of a particle in an electric field of wave packet: Low velocity and relativistic approach

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Diego F.M., E-mail: diegofregolente@gmail.com [Institute for Multiscale Simulations, Friedrich-Alexander Universität, D-91052, Erlangen (Germany); Leonel, Edson D., E-mail: edleonel@rc.unesp.br [Departamento de Estatística, Matemática Aplicada e Computação, UNESP, Univ. Estadual Paulista, Av. 24A, 1515, Bela Vista, 13506-900, Rio Claro, SP (Brazil); Departamento de Física, UNESP, Univ. Estadual Paulista, Av. 24A, 1515, 13506-900, Rio Claro, SP (Brazil)

    2012-11-01

    We study some dynamical properties for the problem of a charged particle in an electric field considering both the low velocity and relativistic cases. The dynamics for both approaches is described in terms of a two-dimensional and nonlinear mapping. The structure of the phase spaces is mixed and we introduce a hole in the chaotic sea to let the particles to escape. By changing the size of the hole we show that the survival probability decays exponentially for both cases. Additionally, we show for the relativistic dynamics, that the introduction of dissipation changes the mixed phase space and attractors appear. We study the parameter space by using the Lyapunov exponent and the average energy over the orbit and show that the system has a very rich structure with infinite family of self-similar shrimp shaped embedded in a chaotic region.

  8. Simulation of Low Velocity Impact Induced Inter- and Intra-Laminar Damage of Composite Beams Based on XFEM

    Science.gov (United States)

    Sun, Wei; Guan, Zhidong; Li, Zengshan

    2017-12-01

    In this paper, the Inter-Fiber Fracture (IFF) criterion of Puck failure theory based on the eXtended Finite Element Method (XFEM) was implemented in ABAQUS code to predict the intra-laminar crack initiation of unidirectional (UD) composite laminate. The transverse crack path in the matrix can be simulated accurately by the presented method. After the crack initiation, the propagation of the crack is simulated by Cohesive Zoom Model (CZM), in which the displacement discontinuities and stress concentration caused by matrix crack is introduced into the finite element (FE) model. Combined with the usage of the enriched element interface, which can be used to simulate the inter-laminar delamination crack, the Low Velocity Impact (LVI) induced damage of UD composite laminate beam with a typical stacking of composite laminates [05/903]S is studied. A complete crack initiation and propagation process was simulated and the numerical results obtained by the XFEM are consistent with the experimental results.

  9. Remarks on global anomalies in RCFT orientifolds

    Energy Technology Data Exchange (ETDEWEB)

    Gato-Rivera, B. [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands); Instituto de Matematicas y Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain); Schellekens, A.N. [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands) and Instituto de Matematicas y Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain) and IMAPP, Radboud Universiteit, Nijmegen (Netherlands)]. E-mail: t58@nikhef.nl

    2006-01-26

    We check the list of supersymmetric standard model orientifold spectra of Dijkstra, Huiszoon and Schellekens for the presence of global anomalies, using probe branes. Absence of global anomalies is found to impose strong constraints, but in nearly all cases they are automatically satisfied by the solutions to the tadpole cancellation conditions.

  10. Chiral anomalies and differential geometry

    International Nuclear Information System (INIS)

    Zumino, B.

    1983-10-01

    Some properties of chiral anomalies are described from a geometric point of view. Topics include chiral anomalies and differential forms, transformation properties of the anomalies, identification and use of the anomalies, and normalization of the anomalies. 22 references

  11. A mega Ultra Low Velocity Zone at the Base of the Iceland Plume: a Target for Tomographic Telescope Implementation

    Science.gov (United States)

    Romanowicz, Barbara; Yuan, Kaiqing; Masson, Yder; Adourian, Sevan

    2017-04-01

    We have recently constructed the first global whole mantle radially anisotropic shear wave velocity model based on time domain full waveform inversion and numerical wavefield computations using the Spectral Element Method (French et al., 2013; French and Romanowicz, 2014). This model's most salient features are broad chimney-like low velocity conduits, rooted within the large-low-shear-velocity provinces (LLSVPs) at the base of the mantle, and extending from the core-mantle boundary up through most of the lower mantle, projecting to the earth's surface in the vicinity of major hotspots. The robustness of these features is confirmed through several non-linear synthetic tests, which we present here, including several iterations of inversion using a different starting model than that which served for the published model. The roots of these not-so-classical "plumes" are regions of more pronounced low shear velocity. While the detailed structure is not yet resolvable tomographically, at least two of them contain large (>800 km diameter) ultra-low-velocity zones (ULVZs), one under Hawaii (Cottaar and Romanowicz, 2012) and the other one under Samoa (Thorne et al., 2013). Through 3D numerical forward modelling of Sdiff phases down to 10s period, using data from broadband arrays illuminating the base of the Iceland plume from different directions, we show that such a large ULVZ also exists at the root of this plume, embedded within a taller region of moderately reduced low shear velocity, such as proposed by He et al. (2015). We also show that such a wide, but localized ULVZ is unique in a broad region around the base of the Iceland Plume. Because of the intense computational effort required for forward modelling of trial structures, to first order this ULVZ is represented by a cylindrical structure of diameter 900 km, height 20 km and velocity reduction 20%. To further refine the model, we have developed a technique which we call "tomographic telescope", in which we are

  12. THE PUZZLING EARLY DETECTION OF LOW VELOCITY 56Ni DECAY LINES IN SN 2014J: HINTS OF A COMPACT REMNANT

    International Nuclear Information System (INIS)

    Ouyed, Rachid; Leahy, Denis; Koning, Nico; Staff, Jan

    2015-01-01

    We show that the low-velocity 56 Ni decay lines detected earlier than expected in the type Ia SN 2014J find an explanation in the quark-nova Ia model, which involves the thermonuclear explosion of a tidally disrupted sub-Chandrasekhar white dwarf (WD) in a tight neutron-star-WD binary system. The explosion is triggered by impact from the quark-nova (QN) ejecta on the WD material; the QN is the explosive transition of the neutron star to a quark star (QS) triggered by accretion from a CO torus (the circularized WD material). The presence of a compact remnant (the QS) provides: (1) an additional energy source (spin-down power) which allows us to fit the observed light-curve including the steep early rise; (2) a central gravitational potential which slows down some of the 56 Ni produced to velocities of a few 10 3 km s –1 . In our model, the 56 Ni decay lines become optically visible at ∼20 days from explosion time in agreement with observations. We list predictions that can provide important tests for our model

  13. Effect of impact energy on damage resistance and mechanical property of C/SiC composites under low velocity impact

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Hui, E-mail: phdhuimei@yahoo.com; Yu, Changkui; Xu, Yawei; Han, Daoyang; Cheng, Laifei

    2017-02-27

    The present study investigated the damage resistance of two dimensional carbon fiber reinforced silicon carbide (C/SiCs) composites subjected to low velocity impact (LVI). Damage microstructures of specimens under different impact energies (E{sub i}) were characterized by infrared thermography, X-ray computed tomography and scanning electron microscopy. The real damage radii of specimens were found to change slightly with E{sub i}, whereas apparent damage radii where much larger. Overall, the fabricated 2D C/SiC composites exhibited good damage resistance to LVI with nominal post-impact tensile strengths remaining at 89.4%, 83.35%, 76.97%, and 74.84% of their pre-impacted counterpart of 158 MPa, for impact energies of 3, 4, 5, and 6 J, respectively. Compared with the as-received one, after LVI real tensile strengths of the C/SiC composite specimens increased by 5.84% for the E{sub i} of 3 J, 9.27% for 4 J, −1.83% for 5 J, −3.16% for 6 J.

  14. Kohn anomalies in superconductors

    International Nuclear Information System (INIS)

    Flatte, M.E.

    1994-01-01

    The detailed behavior of phonon dispersion curves near momenta which span the electronic Fermi sea in a superconductor is presented. An anomaly, similar to the metallic Kohn anomaly, exists in a superconductor's dispersion curves when the frequency of the photon spanning the Fermi sea exceeds twice the superconducting energy gap. This anomaly occurs at approximately the same momentum but is stronger than the normal-state Kohn anomaly. It also survives at finite temperature, unlike the metallic anomaly. Determination of Fermi-surface diameters from the location of these anomalies, therefore, may be more successful in the superconducting phase than in the normal state. However, the superconductor's anomaly fades rapidly with increased phonon frequency and becomes unobservable when the phonon frequency greatly exceeds the gap. This constraint makes these anomalies useful only in high-temperature superconductors such as La 1.85 Sr 0.15 CuO 4

  15. Tracheobronchial Branching Anomalies

    International Nuclear Information System (INIS)

    Hong, Min Ji; Kim, Young Tong; Jou, Sung Shick; Park, A Young

    2010-01-01

    There are various congenital anomalies with respect to the number, length, diameter, and location of tracheobronchial branching patterns. The tracheobronchial anomalies are classified into two groups. The first one, anomalies of division, includes tracheal bronchus, cardiac bronchus, tracheal diverticulum, pulmonary isomerism, and minor variations. The second one, dysmorphic lung, includes lung agenesis-hypoplasia complex and lobar agenesis-aplasia complex

  16. Tracheobronchial Branching Anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Min Ji; Kim, Young Tong; Jou, Sung Shick [Soonchunhyang University, Cheonan Hospital, Cheonan (Korea, Republic of); Park, A Young [Soonchunhyang University College of Medicine, Asan (Korea, Republic of)

    2010-04-15

    There are various congenital anomalies with respect to the number, length, diameter, and location of tracheobronchial branching patterns. The tracheobronchial anomalies are classified into two groups. The first one, anomalies of division, includes tracheal bronchus, cardiac bronchus, tracheal diverticulum, pulmonary isomerism, and minor variations. The second one, dysmorphic lung, includes lung agenesis-hypoplasia complex and lobar agenesis-aplasia complex

  17. Low Velocity Seismic Waves Produced by Stick-Slip Processes During the Drainage of Two Supraglacial Lakes in Greenland

    Science.gov (United States)

    Kenyon, P. M.; Orantes, E. J.; Grynewize, S.; Tedesco, M.

    2016-12-01

    The drainage of supraglacial lakes over the Greenland ice sheet has been shown to have a significant impact on ice dynamics and subglacial hydrology. As supraglacial lakes drain, they produce seismic waves that can be detected on both local and regional scales. Studying such waves and the originating phenomena has the potential to advance our understanding of the subglacial processes involved. Here we present the results of an analysis of high frequency seismic waves generated during the drainage of two supraglacial lakes in southwestern Greenland. The two lakes drained by contrasting mechanisms. One (Lake Half Moon) drained slowly by overflow into an existing moulin. Here GPS data, recorded during the drainage, show an increase in ice sheet velocity that begins well before the time of maximum lake depth. The other lake (Lake Ponting) drained suddenly by hydrofracture through the lake bed. In this case, the GPS data show an increase in velocity that is essentially simultaneous with the maximum lake depth. In both cases, vertical component seismograms were obtained from the Greenland Ice Sheet Monitoring Network (GLISN) for several hours before and after the lake drainage. Arrival times were picked manually, using the criterion that an arrival must have a minimum amplitude of twice the noise level. The arrivals were then plotted on graphs of time versus distance from the lake in question. Several linear trends are visible on each graph. The velocities calculated from the slopes of these trends are unexpectedly low. We suggest that one explanation for this might be that the waves are traveling in a layer of till at the base of the ice sheet, that forms a low velocity channel. When compared with GPS and lake depth data, the origin times of the waves coincide with the velocity increase in both cases. Therefore, we conclude that the waves are being generated by stick-slip processes involving the slippage of the ice sheet on an underlying layer of till.

  18. The focusing effect of P-wave in the Moon's and Earth's low-velocity core. Analytical solution

    Science.gov (United States)

    Fatyanov, A. G.; Burmin, V. Yu

    2018-04-01

    The important aspect in the study of the structure of the interiors of planets is the question of the presence and state of core inside them. While for the Earth this task was solved long ago, the question of whether the core of the Moon is in a liquid or solid state up to the present is debatable up to present. If the core of the Moon is liquid, then the velocity of longitudinal waves in it should be lower than in the surrounding mantle. If the core is solid, then most likely, the velocity of longitudinal waves in it is higher than in the mantle. Numerical calculations of the wave field allow us to identify the criteria for drawing conclusions about the state of the lunar core. In this paper we consider the problem of constructing an analytical solution for wave fields in a layered sphere of arbitrary radius. A stable analytic solution is obtained for the wave fields of longitudinal waves in a three-layer sphere. Calculations of the total wave fields and rays for simplified models of the Earth and the Moon with real parameters are presented. The analytical solution and the ray pattern showed that the low-velocity cores of the Earth and the Moon possess the properties of a collecting lens. This leads to the emergence of a wave field focusing area. As a result, focused waves of considerable amplitude appear on the surface of the Earth and the Moon. In the Earth case, they appear before the first PKP-wave arrival. These are so-called "precursors", which continue in the subsequent arrivals of waves. At the same time, for the simplified model of the Earth, the maximum amplitude growth is observed in the 147-degree region. For the Moon model, the maximum amplitude growth is around 180°.

  19. Crack wave propagation along fracture with an induced low-velocity layer; Teisokudo no chika kiretsu zone wo denpasuru kiretsuha no bunsan tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Nagano, K [Muroran Institute of Technology, Hokkaido (Japan)

    1997-10-22

    A study has been performed on underground cracks working as a geothermy reservoir layer, with respect to characteristics of elastic waves propagating with their energy concentrated on a boundary between rocks around the cracks and fluid in the underground cracks, or `crack waves`. The study has modeled a multi-crack reservoir layer according to the three-layer structure of the fluid layer and low-velocity solid layers around the former layer, whereas crack waves propagating therein were discussed for their dispersion characteristics. As a result of discussions, a guideline to the crack wave measurement at actual fields was put together as follows: because the low-velocity layer affects the dispersion characteristics of the crack waves, the structure and characteristics of the multi-crack reservoir layer may possibly be evaluated by measuring the velocity of the crack waves; evaluating the low-velocity layers requires proper selection of frequency of the crack wave to be measured; for example, at the Higashi Hachimantai field, a crack wave of several hundred hertz must be analyzed; and thickness of the low-velocity layers around main cracks, which can be estimated from the velocity of the crack wave is two meters at the greatest. 6 refs., 3 figs., 2 tabs.

  20. Branchial anomalies in children.

    Science.gov (United States)

    Bajaj, Y; Ifeacho, S; Tweedie, D; Jephson, C G; Albert, D M; Cochrane, L A; Wyatt, M E; Jonas, N; Hartley, B E J

    2011-08-01

    Branchial cleft anomalies are the second most common head and neck congenital lesions seen in children. Amongst the branchial cleft malformations, second cleft lesions account for 95% of the branchial anomalies. This article analyzes all the cases of branchial cleft anomalies operated on at Great Ormond Street Hospital over the past 10 years. All children who underwent surgery for branchial cleft sinus or fistula from January 2000 to December 2010 were included in this study. In this series, we had 80 patients (38 female and 42 male). The age at the time of operation varied from 1 year to 14 years. Amongst this group, 15 patients had first branchial cleft anomaly, 62 had second branchial cleft anomaly and 3 had fourth branchial pouch anomaly. All the first cleft cases were operated on by a superficial parotidectomy approach with facial nerve identification. Complete excision was achieved in all these first cleft cases. In this series of first cleft anomalies, we had one complication (temporary marginal mandibular nerve weakness. In the 62 children with second branchial cleft anomalies, 50 were unilateral and 12 were bilateral. In the vast majority, the tract extended through the carotid bifurcation and extended up to pharyngeal constrictor muscles. Majority of these cases were operated on through an elliptical incision around the external opening. Complete excision was achieved in all second cleft cases except one who required a repeat excision. In this subgroup, we had two complications one patient developed a seroma and one had incomplete excision. The three patients with fourth pouch anomaly were treated with endoscopic assisted monopolar diathermy to the sinus opening with good outcome. Branchial anomalies are relatively common in children. There are three distinct types, first cleft, second cleft and fourth pouch anomaly. Correct diagnosis is essential to avoid inadequate surgery and multiple procedures. The surgical approach needs to be tailored to the type

  1. Coexistence of bilateral first and second branchial arch anomalies

    Science.gov (United States)

    Thakur, J S; Shekar, Vidya; Saluja, Manika; Mohindroo, N K

    2013-01-01

    Branchial arch anomalies are one of the most common congenital anomalies that are usually unilateral and bilateral presentation is rare. The simultaneous presence of bilateral second branchial arch anomalies along with bilateral first arch anomalies is extremely rare, with only three such cases reported in the literature. We present two non-syndromic cases of coexisting bilateral first and second arch anomalies. Developmental anomalies of the branchial apparatus account for 17% of all paediatric cervical masses and are the most common type of congenital cervical mass. They usually present in the paediatric age group. About 96–97% of these anomalies are unilateral. Bilateral presentation is seen in 2–3% having a strong familial association. Congenital syndromes also have been associated with first and second branchial arch anomalies. Thorough clinical examination and investigations should be done to rule out these syndromes. PMID:23580675

  2. Deep Mantle Origin for the DUPAL Anomaly?

    Science.gov (United States)

    Ingle, S.; Weis, D.

    2002-12-01

    Twenty years after the discovery of the Dupal Anomaly, its origin remains a geochemical and geophysical enigma. This anomaly is associated with the Southern Hemisphere oceanic mantle and is recognized by basalts with geochemical characteristics such as low 206Pb/204Pb and high 87Sr/86Sr. Both mid-ocean ridge basalts (MORB) and ocean island basalts (OIB) are affected, despite originating from melting at different depths and of different mantle sources. We compile geochemical data for both MORB and OIB from the three major oceans to help constrain the physical distribution and chemical composition of the Dupal Anomaly. There is a clear decrease in 206Pb/204Pb and an increase in 87Sr/86Sr with more southerly latitude for Indian MORB and OIB; these correlations are less obvious in the Atlantic and non-existent in the Pacific. The average* 143Nd/144Nd for Pacific and Atlantic OIB is 0.5129, but is lower for Indian OIB (0.5128). Interestingly, Pacific, Atlantic and Indian OIB all have 176Hf/177Hf averages of 0.2830. Indian MORB also record this phenomenon of low Nd with normal Hf isotopic compositions (Chauvel and Blichert-Toft, EPSL, 2001). Hf isotopes appear, therefore, to be a valid isotopic proxy for measuring the presence and magnitude of the Dupal Anomaly at specific locations. Wen (EPSL, 2001) reported a low-velocity layer at the D'' boundary beneath the Indian Ocean from which the Dupal Anomaly may originate. This hypothesis may be consistent with our compilations demonstrating that the long-lived Dupal Anomaly does not appear to be either mixing efficiently into the upper mantle or spreading to other ocean basins through time. We suggest that the Dupal source could be continually tapped by upwelling Indian Ocean mantle plumes. Plumes would then emplace pockets of Dupal material into the upper mantle and other ascending plumes might further disperse this material into the shallow asthenosphere. This could explain both the presence of the Dupal signature in MORB

  3. Global gravitational anomalies

    International Nuclear Information System (INIS)

    Witten, E.

    1985-01-01

    A general formula for global gauge and gravitational anomalies is derived. It is used to show that the anomaly free supergravity and superstring theories in ten dimensions are all free of global anomalies that might have ruined their consistency. However, it is shown that global anomalies lead to some restrictions on allowed compactifications of these theories. For example, in the case of O(32) superstring theory, it is shown that a global anomaly related to π 7 (O(32)) leads to a Dirac-like quantization condition for the field strength of the antisymmetric tensor field. Related to global anomalies is the question of the number of fermion zero modes in an instanton field. It is argued that the relevant gravitational instantons are exotic spheres. It is shown that the number of fermion zero modes in an instanton field is always even in ten dimensional supergravity. (orig.)

  4. Anomaly-free models for flavour anomalies

    Science.gov (United States)

    Ellis, John; Fairbairn, Malcolm; Tunney, Patrick

    2018-03-01

    We explore the constraints imposed by the cancellation of triangle anomalies on models in which the flavour anomalies reported by LHCb and other experiments are due to an extra U(1)^' gauge boson Z^' . We assume universal and rational U(1)^' charges for the first two generations of left-handed quarks and of right-handed up-type quarks but allow different charges for their third-generation counterparts. If the right-handed charges vanish, cancellation of the triangle anomalies requires all the quark U(1)^' charges to vanish, if there are either no exotic fermions or there is only one Standard Model singlet dark matter (DM) fermion. There are non-trivial anomaly-free models with more than one such `dark' fermion, or with a single DM fermion if right-handed up-type quarks have non-zero U(1)^' charges. In some of the latter models the U(1)^' couplings of the first- and second-generation quarks all vanish, weakening the LHC Z^' constraint, and in some other models the DM particle has purely axial couplings, weakening the direct DM scattering constraint. We also consider models in which anomalies are cancelled via extra vector-like leptons, showing how the prospective LHC Z^' constraint may be weakened because the Z^' → μ ^+ μ ^- branching ratio is suppressed relative to other decay modes.

  5. First branchial groove anomaly.

    Science.gov (United States)

    Kumar, M; Hickey, S; Joseph, G

    2000-06-01

    First branchial groove anomalies are very rare. We report a case of a first branchial groove anomaly presented as an infected cyst in an 11-month-old child. Management of such lesions is complicated because of their close association with the facial nerve. Surgical management must include identification and protection of the facial nerve. Embryology and facial nerve disposition in relation to the anomaly are reviewed.

  6. Dental Anomalies: An Update

    Directory of Open Access Journals (Sweden)

    Fatemeh Jahanimoghadam

    2016-01-01

    Full Text Available Dental anomalies are usual congenital malformation that can happen either as isolated findings or as a part of a syndrome. Developmental anomalies influencing the morphology exists in both deciduous and permanent dentition and shows different forms such as gemination, fusion, concrescence, dilaceration, dens evaginatus (DE, enamel pearls, taurodontism or peg-shaped laterals. All These anomalies have clinical significance concerning aesthetics, malocclusion and more necessary preparing of the development of dental decays and oral diseases. Through a search in PubMed, Google, Scopus and Medline, a total of eighty original research papers during 1928-2016 were found with the keywords such as dental anomaly, syndrome, tooth and hypodontia. One hundred review titles were identified, eighty reviews were retrieved that were finally included as being relevant and of sufficient quality. In this review, dental anomalies including gemination, fusion, concrescence, dilaceration, dens invaginatus, DE, taurodontism, enamel pearls, fluorosis, peg-shaped laterals, dentinal dysplasia, regional odontodysplasia and hypodontia are discussed. Diagnosing dental abnormality needs a thorough evaluation of the patient, involving a medical, dental, familial and clinical history. Clinical examination and radiographic evaluation and in some of the cases, specific laboratory tests are also needed. Developmental dental anomalies require careful examination and treatment planning. Where one anomaly is present, clinicians should suspect that other anomalies may also be present. Moreover, careful clinical and radiographical examination is required. Furthermore, more complex cases need multidisciplinary planning and treatment.

  7. Introduction to anomalies

    International Nuclear Information System (INIS)

    Alvarez-Gaume, L.

    1986-01-01

    These lectures are dedicated to the study of the recent progress and implications of anomalies in quantum field theory. In this introduction the author recapitulates some of the highlights in the history of the subject. The outline of these lectures is as follows: Section II contains a quick review of spinors in Euclidean and Minkowski space, some other group theory results relevant for the computation of anomalies in various dimensions, and an exposition of the index theorem. Section III starts the analysis of fermion determinants and chiral effective actions by deriving the non-Abelian anomaly from index theory. Using the results of Section II, the anomaly cancellation recently discovered by Green and Schwarz will be presented in Section IV as well as the connection of these results of Section III with the descent equations and the Wess-Zumino-Witten Lagrangians. Section V contains the generalization of anomalies to σ-models and some of its application in string theory. Section VI will deal with the anomalies from the Hamiltonian point of view. An exact formula for the imaginary part of the effective action for chiral fermions in the presence of arbitrary external gauge and gravitational fields will be derived in Section VII, and used in Section VIII for the study of global anomalies. 85 references

  8. Anomalies on orbifolds

    Energy Technology Data Exchange (ETDEWEB)

    Arkani-Hamed, Nima; Cohen, Andrew G.; Georgi, Howard

    2001-03-16

    We discuss the form of the chiral anomaly on an S1/Z2 orbifold with chiral boundary conditions. We find that the 4-divergence of the higher-dimensional current evaluated at a given point in the extra dimension is proportional to the probability of finding the chiral zero mode there. Nevertheless the anomaly, appropriately defined as the five dimensional divergence of the current, lives entirely on the orbifold fixed planes and is independent of the shape of the zero mode. Therefore long distance four dimensional anomaly cancellation ensures the consistency of the higher dimensional orbifold theory.

  9. Skyrmions and anomalies

    International Nuclear Information System (INIS)

    Rho, M.

    1987-02-01

    The author summarizes the works presented at the meeting on skyrmions and anomalies. He divides the principal issues of this workshop into five categories: QCD effective lagrangians, chiral bags and the Cheshire cat principle, strangeness problem, phenomenology, mathematical structure

  10. Anomaly Detection in Sequences

    Data.gov (United States)

    National Aeronautics and Space Administration — We present a set of novel algorithms which we call sequenceMiner, that detect and characterize anomalies in large sets of high-dimensional symbol sequences that...

  11. Kohn anomaly in graphene

    International Nuclear Information System (INIS)

    Milosevic, I.; Kepcija, N.; Dobardzic, E.; Damnjanovic, M.; Mohr, M.; Maultzsch, J.; Thomsen, C.

    2011-01-01

    Symmetry based analysis of the Kohn anomaly is performed. Kohn phonon frequencies and displacements are calculated by force constant method. It is shown that Kohn phonon vibrations cause electronic band gap opening.

  12. Algebraic structure of chiral anomalies

    International Nuclear Information System (INIS)

    Stora, R.

    1985-09-01

    I will describe first the algebraic aspects of chiral anomalies, exercising however due care about the topological delicacies. I will illustrate the structure and methods in the context of gauge anomalies and will eventually make contact with results obtained from index theory. I will go into two sorts of generalizations: on the one hand, generalizing the algebraic set up yields e.g. gravitational and mixed gauge anomalies, supersymmetric gauge anomalies, anomalies in supergravity theories; on the other hand most constructions applied to the cohomologies which characterize anomalies easily extend to higher cohomologies. Section II is devoted to a description of the general set up as it applies to gauge anomalies. Section III deals with a number of algebraic set ups which characterize more general types of anomalies: gravitational and mixed gauge anomalies, supersymmetric gauge anomalies, anomalies in supergravity theories. It also includes brief remarks on σ models and a reminder on the full BRST algebra of quantized gauge theories

  13. Anomalies and gravity

    International Nuclear Information System (INIS)

    Mielke, Eckehard W.

    2006-01-01

    Anomalies in Yang-Mills type gauge theories of gravity are reviewed. Particular attention is paid to the relation between the Dirac spin, the axial current j5 and the non-covariant gauge spin C. Using diagrammatic techniques, we show that only generalizations of the U(1)- Pontrjagin four-form F and F = dC arise in the chiral anomaly, even when coupled to gravity. Implications for Ashtekar's canonical approach to quantum gravity are discussed

  14. Fivebrane gravitational anomalies

    International Nuclear Information System (INIS)

    Becker, Katrin; Becker, Melanie

    2000-01-01

    Freed, Harvey, Minasian and Moore (FHMM) have proposed a mechanism to cancel the gravitational anomaly of the M-theory fivebrane coming from diffeomorphisms acting on the normal bundle. This procedure is based on a modification of the conventional M-theory Chern-Simons term. We apply the FHMM mechanism in the ten-dimensional type IIA theory. We then analyze the relation to the anomaly cancellation mechanism for the type IIA fivebrane proposed by Witten

  15. The Holographic Weyl anomaly

    CERN Document Server

    Henningson, M; Henningson, Mans; Skenderis, Kostas

    1998-01-01

    We calculate the Weyl anomaly for conformal field theories that can be described via the adS/CFT correspondence. This entails regularizing the gravitational part of the corresponding supergravity action in a manner consistent with general covariance. Up to a constant, the anomaly only depends on the dimension d of the manifold on which the conformal field theory is defined. We present concrete expressions for the anomaly in the physically relevant cases d = 2, 4 and 6. In d = 2 we find for the central charge c = 3 l/ 2 G_N in agreement with considerations based on the asymptotic symmetry algebra of adS_3. In d = 4 the anomaly agrees precisely with that of the corresponding N = 4 superconformal SU(N) gauge theory. The result in d = 6 provides new information for the (0, 2) theory, since its Weyl anomaly has not been computed previously. The anomaly in this case grows as N^3, where N is the number of coincident M5 branes, and it vanishes for a Ricci-flat background.

  16. LOW-VELOCITY SHOCKS TRACED BY EXTENDED SiO EMISSION ALONG THE W43 RIDGES: WITNESSING THE FORMATION OF YOUNG MASSIVE CLUSTERS

    International Nuclear Information System (INIS)

    Nguyen-Luong, Q.; Martin, P. G.; Motte, F.; Louvet, F.; Hill, T.; Hennemann, M.; Didelon, P.; Carlhoff, P.; Schilke, P.; Lesaffre, P.; Gusdorf, A.; Schneider, N.; Bontemps, S.; Duarte-Cabral, A.; Menten, K. M.; Wyrowski, F.; Bendo, G.; Roussel, H.; Bernard, J.-P.; Bronfman, L.

    2013-01-01

    The formation of high-mass stars is tightly linked to that of their parental clouds. Here, we focus on the high-density parts of W43, a molecular cloud undergoing an efficient event of star formation. Using a column density image derived from Herschel continuum maps, we identify two high-density filamentary clouds, called the W43-MM1 and W43-MM2 ridges. Both have gas masses of 2.1 × 10 4 M ☉ and 3.5 × 10 4 M ☉ above >10 23 cm -2 and within areas of ∼6 and ∼14 pc 2 , respectively. The W43-MM1 and W43-MM2 ridges are structures that are coherent in velocity and gravitationally bound, despite their large velocity dispersion measured by the N 2 H + (1-0) lines of the W43-HERO IRAM large program. Another intriguing result is that these ridges harbor widespread (∼10 pc 2 ) bright SiO (2-1) emission, which we interpret to be the result of low-velocity shocks (≤10 km s –1 ). We measure a significant relationship between the SiO (2-1) luminosity and velocity extent and show that it distinguishes our observations from the high-velocity shocks associated with outflows. We use state-of-the-art shock models to demonstrate that a small percentage (10%) of Si atoms in low-velocity shocks, observed initially in gas phase or in grain mantles, can explain the observed SiO column density in the W43 ridges. The spatial and velocity overlaps between the ridges of high-density gas and the shocked SiO gas suggest that ridges could be forming via colliding flows driven by gravity and accompanied by low-velocity shocks. This mechanism may be the initial conditions for the formation of young massive clusters

  17. Low-velocity Shocks Traced by Extended SiO Emission along the W43 Ridges: Witnessing the Formation of Young Massive Clusters

    Science.gov (United States)

    Nguyen-Lu'o'ng, Q.; Motte, F.; Carlhoff, P.; Louvet, F.; Lesaffre, P.; Schilke, P.; Hill, T.; Hennemann, M.; Gusdorf, A.; Didelon, P.; Schneider, N.; Bontemps, S.; Duarte-Cabral, A.; Menten, K. M.; Martin, P. G.; Wyrowski, F.; Bendo, G.; Roussel, H.; Bernard, J.-P.; Bronfman, L.; Henning, T.; Kramer, C.; Heitsch, F.

    2013-10-01

    The formation of high-mass stars is tightly linked to that of their parental clouds. Here, we focus on the high-density parts of W43, a molecular cloud undergoing an efficient event of star formation. Using a column density image derived from Herschel continuum maps, we identify two high-density filamentary clouds, called the W43-MM1 and W43-MM2 ridges. Both have gas masses of 2.1 × 104 M ⊙ and 3.5 × 104 M ⊙ above >10^{23}\\, {{cm}^{-2}} and within areas of ~6 and ~14 pc2, respectively. The W43-MM1 and W43-MM2 ridges are structures that are coherent in velocity and gravitationally bound, despite their large velocity dispersion measured by the N2H+ (1-0) lines of the W43-HERO IRAM large program. Another intriguing result is that these ridges harbor widespread (~10 pc2) bright SiO (2-1) emission, which we interpret to be the result of low-velocity shocks (models to demonstrate that a small percentage (10%) of Si atoms in low-velocity shocks, observed initially in gas phase or in grain mantles, can explain the observed SiO column density in the W43 ridges. The spatial and velocity overlaps between the ridges of high-density gas and the shocked SiO gas suggest that ridges could be forming via colliding flows driven by gravity and accompanied by low-velocity shocks. This mechanism may be the initial conditions for the formation of young massive clusters.

  18. Muon g−2 in anomaly mediated SUSY breaking

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhury, Debtosh; Yokozaki, Norimi [Istituto Nazionale di Fisica Nucleare, Sezione di Roma,Piazzale Aldo Moro 2, I-00185 Rome (Italy)

    2015-08-24

    Motivated by two experimental facts, the muon g−2 anomaly and the observed Higgs boson mass around 125 GeV, we propose a simple model of anomaly mediation, which can be seen as a generalization of mixed modulus-anomaly mediation. In our model, the discrepancy of the muon g−2 and the Higgs boson mass around 125 GeV are easily accommodated. The required mass splitting between the strongly and weakly interacting SUSY particles are naturally achieved by the contribution from anomaly mediation. This model is easily consistent with SU(5) or SO(10) grand unified theory.

  19. Muon g−2 in anomaly mediated SUSY breaking

    International Nuclear Information System (INIS)

    Chowdhury, Debtosh; Yokozaki, Norimi

    2015-01-01

    Motivated by two experimental facts, the muon g−2 anomaly and the observed Higgs boson mass around 125 GeV, we propose a simple model of anomaly mediation, which can be seen as a generalization of mixed modulus-anomaly mediation. In our model, the discrepancy of the muon g−2 and the Higgs boson mass around 125 GeV are easily accommodated. The required mass splitting between the strongly and weakly interacting SUSY particles are naturally achieved by the contribution from anomaly mediation. This model is easily consistent with SU(5) or SO(10) grand unified theory.

  20. RARE BRANCHIAL ARCH ANOMALIES

    Directory of Open Access Journals (Sweden)

    Jayanta Kumar

    2016-03-01

    Full Text Available AIM Amongst the branchial arch anomalies third arch anomaly occurs rarely and more so the fourth arch anomalies. We present our experience with cases of rare branchial arch anomalies. PATIENTS AND METHODS From June 2006 to January 2016, cases having their external opening in the lower third of sternocleidomastoid muscle with the tract going through thyroid gland and directing to pyriform sinus (PFS or cysts with internal opening in the PFS were studied. RESULTS No fourth arch anomaly was encountered. One cyst with internal opening which later on formed a fistula, three fistulae from beginning and two sinuses were encountered. The main stay of diagnosis was the fistula in the PFS and the tract lying posterior to the internal carotid artery. Simple excision technique with a small incision around the external opening was done. There was no recurrence. CONCLUSION Third arch fistula is not very rare as it was thought. Internal fistula is found in most of the cases. Though radiological investigations are helpful, fistulae can be diagnosed clinically and during operation. Extensive operation of the neck, mediastinum and pharynx is not required.

  1. Charge-state correlated cross sections for the production of low-velocity highly charged Ne ions by heavy-ion bombardment

    International Nuclear Information System (INIS)

    Gray, T.J.; Cocke, C.L.; Justiniano, E.

    1980-01-01

    We report measured cross sections for the collisional production of highly charged low-velocity Ne recoil ions resulting from the bombardment of a thin Ne gas target by highly charged 1-MeV/amu C, N, O, and F projectiles. The measurements were made using time-of-flight techniques which allowed the simultaneous identification of the final charge state of both the low-velocity recoil ion and the high-velocity projectile for each collision event. For a given incident-projectile charge state, the recoil charge-state distribution is very dependent upon the final charge state of the projectile. Single- and double-electron capture events by incident bare nuclei and projectile K-shell ionization during the collision cause large shifts in the recoil charge-state distributions toward higher charge states. A previously proposed energy-deposition model is modified to include the effects of projectile charge-changing collisions during the collision for bare and hydrogenlike projectiles and is used to discuss the present experimental results

  2. Analytical and Mathematical Modeling and Optimization of Fiber Metal Laminates (FMLs subjected to low-velocity impact via combined response surface regression and zero-One programming

    Directory of Open Access Journals (Sweden)

    Faramarz Ashenai Ghasemi

    Full Text Available This paper presents analytical and mathematical modeling and optimization of the dynamic behavior of the fiber metal laminates (FMLs subjected to low-velocity impact. The deflection to thickness (w/h ratio has been identified through the governing equations of the plate that are solved using the first-order shear deformation theory as well as the Fourier series method. With the help of a two degrees-of-freedom system, consisting of springs-masses, and the Choi's linearized Hertzian contact model the interaction between the impactor and the plate is modeled. Thirty-one experiments are conducted on samples of different layer sequences and volume fractions of Al plies in the composite Structures. A reliable fitness function in the form of a strict linear mathematical function constructed. Using an ordinary least square method, response regression coefficients estimated and a zero-one programming technique proposed to optimize the FML plate behavior subjected to any technological or cost restrictions. The results indicated that FML plate behavior is highly affected by layer sequences and volume fractions of Al plies. The results also showed that, embedding Al plies at outer layers of the structure significantly results in a better response of the structure under low-velocity impact, instead of embedding them in the middle or middle and outer layers of the structure.

  3. Non-local Effects of Conformal Anomaly

    Science.gov (United States)

    Meissner, Krzysztof A.; Nicolai, Hermann

    2018-03-01

    It is shown that the nonlocal anomalous effective actions corresponding to the quantum breaking of the conformal symmetry can lead to observable modifications of Einstein's equations. The fact that Einstein's general relativity is in perfect agreement with all observations including cosmological or recently observed gravitational waves imposes strong restrictions on the field content of possible extensions of Einstein's theory: all viable theories should have vanishing conformal anomalies. It is shown that a complete cancellation of conformal anomalies in D=4 for both the C^2 invariant and the Euler (Gauss-Bonnet) invariant can only be achieved for N-extended supergravity multiplets with N ≥ 5.

  4. Positively deflected anomaly mediation

    International Nuclear Information System (INIS)

    Okada, Nobuchika

    2002-01-01

    We generalize the so-called 'deflected anomaly mediation' scenario to the case where threshold corrections of heavy messengers to the sparticle squared masses are positive. A concrete model realizing this scenario is also presented. The tachyonic slepton problem can be fixed with only a pair of messengers. The resultant sparticle mass spectrum is quite different from that in the conventional deflected anomaly mediation scenario, but is similar to the one in the gauge mediation scenario. The lightest sparticle is mostly B-ino

  5. Congenital laryngeal anomalies,

    Directory of Open Access Journals (Sweden)

    Michael J. Rutter

    2014-12-01

    Full Text Available Introduction: It is essential for clinicians to understand issues relevant to the airway management of infants and to be cognizant of the fact that infants with congenital laryngeal anomalies are at particular risk for an unstable airway. Objectives: To familiarize clinicians with issues relevant to the airway management of infants and to present a succinct description of the diagnosis and management of an array of congenital laryngeal anomalies. Methods: Revision article, in which the main aspects concerning airway management of infants will be analyzed. Conclusions: It is critical for clinicians to understand issues relevant to the airway management of infants.

  6. Winter to winter recurrence of atmospheric circulation anomalies over East Asia and its impact on winter surface air temperature anomalies.

    Science.gov (United States)

    Zhao, Xia; Yang, Guang

    2017-01-01

    The persistence of atmospheric circulation anomalies over East Asia shows a winter to winter recurrence (WTWR) phenomenon. Seasonal variations in sea level pressure anomalies and surface wind anomalies display significantly different characteristics between WTWR and non-WTWR years. The WTWR years are characterized by the recurrence of both a strong (weak) anomalous Siberian High and an East Asian winter monsoon over two successive winters without persistence through the intervening summer. However, anomalies during the non-WTWR years have the opposite sign between the current and ensuing winters. The WTWR of circulation anomalies contributes to that of surface air temperature anomalies (SATAs), which is useful information for improving seasonal and interannual climate predictions over East Asia and China. In the positive (negative) WTWR years, SATAs are cooler (warmer) over East Asia in two successive winters, but the signs of the SATAs are opposite in the preceding and subsequent winters during the non-WTWR years.

  7. Sensitivity of ground motion parameters to local site effects for areas characterised by a thick buried low-velocity layer.

    Science.gov (United States)

    Farrugia, Daniela; Galea, Pauline; D'Amico, Sebastiano; Paolucci, Enrico

    2016-04-01

    It is well known that earthquake damage at a particular site depends on the source, the path that the waves travel through and the local geology. The latter is capable of amplifying and changing the frequency content of the incoming seismic waves. In regions of sparse or no strong ground motion records, like Malta (Central Mediterranean), ground motion simulations are used to obtain parameters for purposes of seismic design and analysis. As an input to ground motion simulations, amplification functions related to the shallow subsurface are required. Shear-wave velocity profiles of several sites on the Maltese islands were obtained using the Horizontal-to-Vertical Spectral Ratio (H/V), the Extended Spatial Auto-Correlation (ESAC) technique and the Genetic Algorithm. The sites chosen were all characterised by a layer of Blue Clay, which can be up to 75 m thick, underlying the Upper Coralline Limestone, a fossiliferous coarse grained limestone. This situation gives rise to a velocity inversion. Available borehole data generally extends down till the top of the Blue Clay layer therefore the only way to check the validity of the modelled shear-wave velocity profile is through the thickness of the topmost layer. Surface wave methods are characterised by uncertainties related to the measurements and the model used for interpretation. Moreover the inversion procedure is also highly non-unique. Such uncertainties are not commonly included in site response analysis. Yet, the propagation of uncertainties from the extracted dispersion curves to inversion solutions can lead to significant differences in the simulations (Boaga et al., 2011). In this study, a series of sensitivity analyses will be presented with the aim of better identifying those stratigraphic properties which can perturb the ground motion simulation results. The stochastic one-dimensional site response analysis algorithm, Extended Source Simulation (EXSIM; Motazedian and Atkinson, 2005), was used to perform

  8. <strong>Mini-project>

    DEFF Research Database (Denmark)

    Katajainen, Jyrki

    2008-01-01

    In this project the goal is to develop the safe * family of containers for the CPH STL. The containers to be developed should be safer and more reliable than any of the existing implementations. A special focus should be put on strong exception safety since none of the existing prototypes available...

  9. Assessing Asset Pricing Anomalies

    NARCIS (Netherlands)

    W.A. de Groot (Wilma)

    2017-01-01

    markdownabstractOne of the most important challenges in the field of asset pricing is to understand anomalies: empirical patterns in asset returns that cannot be explained by standard asset pricing models. Currently, there is no consensus in the academic literature on the underlying causes of

  10. Anomaly Busters II

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The anomaly busters had struck on the first day of the Kyoto meeting with Yoji Totsuka of Tokyo speaking on baryon number nonjjonservation and 'related topics'. The unstable proton is a vital test of grand unified pictures pulling together the electroweak and quark/gluon forces in a single field theory

  11. Anomaly Busters II

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1985-11-15

    The anomaly busters had struck on the first day of the Kyoto meeting with Yoji Totsuka of Tokyo speaking on baryon number nonjjonservation and 'related topics'. The unstable proton is a vital test of grand unified pictures pulling together the electroweak and quark/gluon forces in a single field theory.

  12. The reactor antineutrino anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Haser, Julia; Buck, Christian; Lindner, Manfred [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    2016-07-01

    Major discoveries were made in the past few years in the field of neutrino flavour oscillation. Nuclear reactors produce a clean and intense flux of electron antineutrinos and are thus an essential neutrino source for the determination of oscillation parameters. Most currently the reactor antineutrino experiments Double Chooz, Daya Bay and RENO have accomplished to measure θ{sub 13}, the smallest of the three-flavour mixing angles. In the course of these experiments two anomalies emerged: (1) the reanalysis of the reactor predictions revealed a deficit in experimentally observed antineutrino flux, known as the ''reactor antineutrino anomaly''. (2) The high precision of the latest generation of neutrino experiments resolved a spectral shape distortion relative to the expected energy spectra. Both puzzles are yet to be solved and triggered new experimental as well as theoretical studies, with the search for light sterile neutrinos as most popular explanation for the flux anomaly. This talk outlines the two reactor antineutrino anomalies. Discussing possible explanations for their occurrence, recent and upcoming efforts to solve the reactor puzzles are highlighted.

  13. Echocardiography in Ebstein's anomaly

    NARCIS (Netherlands)

    W.J. Gussenhoven (Wilhelmina Johanna)

    1984-01-01

    textabstractIn this thesis the value of echocardiography is evaluated for the diagnosis of Ebstein's anomaly of the tricuspid valve. This congenital heart defect, first described in 1866 by Wilhelm Ebstein, is characterized by an apical displacement of the septal and inferior tricuspid valve

  14. Venus - Ishtar gravity anomaly

    Science.gov (United States)

    Sjogren, W. L.; Bills, B. G.; Mottinger, N. A.

    1984-01-01

    The gravity anomaly associated with Ishtar Terra on Venus is characterized, comparing line-of-sight acceleration profiles derived by differentiating Pioneer Venus Orbiter Doppler residual profiles with an Airy-compensated topographic model. The results are presented in graphs and maps, confirming the preliminary findings of Phillips et al. (1979). The isostatic compensation depth is found to be 150 + or - 30 km.

  15. Bolivian Bouguer Anomaly Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1 kilometer Bouguer anomaly grid for the country of Bolivia.Number of columns is 550 and number of rows is 900. The order of the data is from the lower left to the...

  16. Generalized zero point anomaly

    International Nuclear Information System (INIS)

    Nogueira, Jose Alexandre; Maia Junior, Adolfo

    1994-01-01

    It is defined Zero point Anomaly (ZPA) as the difference between the Effective Potential (EP) and the Zero point Energy (ZPE). It is shown, for a massive and interacting scalar field that, in very general conditions, the renormalized ZPA vanishes and then the renormalized EP and ZPE coincide. (author). 3 refs

  17. Minnesota Bouguer Anomaly Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1.5 kilometer Bouguer anomaly grid for the state of Minnesota. Number of columns is 404 and number of rows is 463. The order of the data is from the lower left to...

  18. Estimating crustal thickness using SsPmp in regions covered by low-velocity sediments: Imaging the Moho beneath the Southeastern Suture of the Appalachian Margin Experiment (SESAME) array, SE Atlantic Coastal Plain

    Science.gov (United States)

    Parker, E. Horry, Jr.; Hawman, Robert B.; Fischer, Karen M.; Wagner, Lara S.

    2016-09-01

    Deconvolved waveforms for two earthquakes (Mw: 6.0 and 5.8) show clear postcritical SsPmp arrivals for broadband stations deployed across the coastal plain of Georgia, allowing mapping of crustal thickness in spite of strong reverberations generated by low-velocity sediments. Precritical SsPmp arrivals are also identified. For a basement in which velocity increases linearly with depth, a bootstrapped grid search suggests an average basement velocity of 6.5 ± 0.1 km/s and basement thickness of 29.8 ± 2.0 km. Corresponding normal-incidence Moho two-way times (including sediments) are 10.6 ± 0.6 s, consistent with times for events interpreted as Moho reflections on coincident active-source reflection profiles. Modeling of an underplated mafic layer (Vp = 7.2-7.4 km/s) using travel time constraints from SsPmp data and vertical-incidence Moho reflection times yields a total basement thickness of 30-35 km and average basement velocity of 6.35-6.65 km/s for an underplate thickness of 0-15 km.

  19. Strong interactions

    International Nuclear Information System (INIS)

    Froissart, Marcel

    1976-01-01

    Strong interactions are introduced by their more obvious aspect: nuclear forces. In hadron family, the nucleon octet, OMEGA - decuplet, and quark triply are successively considered. Pion wave having been put at the origin of nuclear forces, low energy phenomena are described, the force being explained as an exchange of structure corresponding to a Regge trajectory in a variable rotating state instead of the exchange of a well defined particle. At high energies the concepts of pomeron, parton and stratons are introduced, pionization and fragmentation are briefly differentiated [fr

  20. Strong tracking adaptive Kalman filters for underwater vehicle dead reckoning

    Institute of Scientific and Technical Information of China (English)

    XIAO Kun; FANG Shao-ji; PANG Yong-jie

    2007-01-01

    To improve underwater vehicle dead reckoning, a developed strong tracking adaptive kalman filter is proposed. The filter is improved with an additional adaptive factor and an estimator of measurement noise covariance. Since the magnitude of fading factor is changed adaptively, the tracking ability of the filter is still enhanced in low velocity condition of underwater vehicles. The results of simulation tests prove the presented filter effective.

  1. Experimental Investigation on Low-velocity Impact and Compression After Impact Properties of Three-dimensional Five-directional Braided Composites

    Directory of Open Access Journals (Sweden)

    YAN Shi

    2017-12-01

    Full Text Available The low-velocity impact and compression after impact (CAI properties of three-dimensional (3D five-directional carbon fiber/epoxy resin braided composites were experimentally investigated. Specimens prepared with different braiding angles were tested at the same impact energy level. Residual post-impact mechanical properties of the different configurations were characterized by compression after impact tests. Results show that the specimens with bigger braiding angle sustain higher peak loads, and smaller impact damage area, mainly attributes to a more compact space construction. The CAI strength and damage mechanism are found to be mainly dependent on the axial support of the braiding fiber tows. With the increase of braiding angle, the CAI strength decreases, and the damage mode of the composites is changed from transverse fracture to shear failure.

  2. Low velocity floor level displacement ventilation systems: Technology assessment. Sistemi di distribuzione dell'aria a pavimento a bassa velocita': Vecchie e nuove conoscenze

    Energy Technology Data Exchange (ETDEWEB)

    Borjesson, J.A.; Bertomeu, L.; Marchetti, F.

    1992-12-01

    Although the concept of floor level air displacement ventilation is not in fact truly innovative given that it has already been tried during the 1980's, this paper shows that the combination of the advantageous natural cooling air circulation dynamics inherent in this method, combined with modern air diffusion equipment, offers interesting opportunities for energy conservation. The thermodynamics/air flow analysis indicates that from 20 to 40% energy savings can be obtained, in addition to reduced ventilation system operating times, with the effective application of low velocity floor level displacement air distribution systems as compared with conventional ventilation systems using the air mixing concept. It is shown how this innovative air cooling/recirculation technique is particularly suitable for conditions characterized by high air infiltration, high heating load and low indoor air pollution.

  3. Algebraic study of chiral anomalies

    Indian Academy of Sciences (India)

    Chiral anomalies; gauge theories; bundles; connections; quantum field ... The algebraic structure of chiral anomalies is made globally valid on non-trivial bundles by the introduction of a fixed background connection. ... Current Issue : Vol.

  4. Ferret Workflow Anomaly Detection System

    National Research Council Canada - National Science Library

    Smith, Timothy J; Bryant, Stephany

    2005-01-01

    The Ferret workflow anomaly detection system project 2003-2004 has provided validation and anomaly detection in accredited workflows in secure knowledge management systems through the use of continuous, automated audits...

  5. Branchial Cleft Anomalies

    Science.gov (United States)

    McPhail, Neil; Mustard, Robert A.

    1966-01-01

    The embryology, anatomy and pathology of branchial cleft anomalies are discussed and 87 cases reviewed. The most frequent anomaly was branchial cleft cyst, of which there were 77 cases. Treatment in all cases consisted of complete excision. There were five cases of external branchial sinus and five cases of complete branchial fistula. Sinograms were helpful in demonstrating these lesions. Excision presented little difficulty. No proved case of branchiogenic carcinoma has been found in the Toronto General Hospital. Five cases are described in which the original diagnosis was branchiogenic carcinoma—in four of these a primary tumour has already been found. The authors believe that the diagnosis of branchiogenic carcinoma should never be accepted until repeated examinations over a period of at least five years have failed to reveal a primary tumour. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5 PMID:5901161

  6. Penile Anomalies in Adolescence

    Directory of Open Access Journals (Sweden)

    Dan Wood

    2011-01-01

    Full Text Available This article considers the impact and outcomes of both treatment and underlying condition of penile anomalies in adolescent males. Major congenital anomalies (such as exstrophy/epispadias are discussed, including the psychological outcomes, common problems (such as corporal asymmetry, chordee, and scarring in this group, and surgical assessment for potential surgical candidates. The emergence of new surgical techniques continues to improve outcomes and potentially raises patient expectations. The importance of balanced discussion in conditions such as micropenis, including multidisciplinary support for patients, is important in order to achieve appropriate treatment decisions. Topical treatments may be of value, but in extreme cases, phalloplasty is a valuable option for patients to consider. In buried penis, the importance of careful assessment and, for the majority, a delay in surgery until puberty has completed is emphasised. In hypospadias patients, the variety of surgical procedures has complicated assessment of outcomes. It appears that true surgical success may be difficult to measure as many men who have had earlier operations are not reassessed in either puberty or adult life. There is also a brief discussion of acquired penile anomalies, including causation and treatment of lymphoedema, penile fracture/trauma, and priapism.

  7. Penile anomalies in adolescence.

    Science.gov (United States)

    Wood, Dan; Woodhouse, Christopher

    2011-03-07

    This article considers the impact and outcomes of both treatment and underlying condition of penile anomalies in adolescent males. Major congenital anomalies (such as exstrophy/epispadias) are discussed, including the psychological outcomes, common problems (such as corporal asymmetry, chordee, and scarring) in this group, and surgical assessment for potential surgical candidates. The emergence of new surgical techniques continues to improve outcomes and potentially raises patient expectations. The importance of balanced discussion in conditions such as micropenis, including multidisciplinary support for patients, is important in order to achieve appropriate treatment decisions. Topical treatments may be of value, but in extreme cases, phalloplasty is a valuable option for patients to consider. In buried penis, the importance of careful assessment and, for the majority, a delay in surgery until puberty has completed is emphasised. In hypospadias patients, the variety of surgical procedures has complicated assessment of outcomes. It appears that true surgical success may be difficult to measure as many men who have had earlier operations are not reassessed in either puberty or adult life. There is also a brief discussion of acquired penile anomalies, including causation and treatment of lymphoedema, penile fracture/trauma, and priapism.

  8. Anomaly General Circulation Models.

    Science.gov (United States)

    Navarra, Antonio

    The feasibility of the anomaly model is assessed using barotropic and baroclinic models. In the barotropic case, both a stationary and a time-dependent model has been formulated and constructed, whereas only the stationary, linear case is considered in the baroclinic case. Results from the barotropic model indicate that a relation between the stationary solution and the time-averaged non-linear solution exists. The stationary linear baroclinic solution can therefore be considered with some confidence. The linear baroclinic anomaly model poses a formidable mathematical problem because it is necessary to solve a gigantic linear system to obtain the solution. A new method to find solution of large linear system, based on a projection on the Krylov subspace is shown to be successful when applied to the linearized baroclinic anomaly model. The scheme consists of projecting the original linear system on the Krylov subspace, thereby reducing the dimensionality of the matrix to be inverted to obtain the solution. With an appropriate setting of the damping parameters, the iterative Krylov method reaches a solution even using a Krylov subspace ten times smaller than the original space of the problem. This generality allows the treatment of the important problem of linear waves in the atmosphere. A larger class (nonzonally symmetric) of basic states can now be treated for the baroclinic primitive equations. These problem leads to large unsymmetrical linear systems of order 10000 and more which can now be successfully tackled by the Krylov method. The (R7) linear anomaly model is used to investigate extensively the linear response to equatorial and mid-latitude prescribed heating. The results indicate that the solution is deeply affected by the presence of the stationary waves in the basic state. The instability of the asymmetric flows, first pointed out by Simmons et al. (1983), is active also in the baroclinic case. However, the presence of baroclinic processes modifies the

  9. Common dental anomalies in cleft lip and palate patients.

    Science.gov (United States)

    Haque, Sanjida; Alam, Mohammad Khursheed

    2015-01-01

    Cleft lip and palate (CLP) is the most common orofacial congenital malformation in live births. CLP can occur individually or in combination with other congenital deformities. Affected patients experience a number of dental, aesthetic, speech, hearing, and psychological complications and have a higher incidence of severe dental conditions. The purpose of this study is to characterise the different types of dental anomalies that are frequently associated with CLP patients based on a literature survey. By literature survey, this study characterises the different types of dental anomalies that are frequently associated with cleft lip and palate patients. Common dental anomalies associated with CLP are supernumerary tooth, congenitally missing tooth, delayed tooth development, morphological anomalies in both deciduous and permanent dentition, delayed eruption of permanent maxillary incisors, microdontia, and abnormal tooth number. The incidence of certain dental anomalies is strongly correlated with Cleft lip and palate, a finding that is consistent with previous studies.

  10. Tau anomaly and vectorlike families

    International Nuclear Information System (INIS)

    Babu, K.S.; Pati, J.C.; Zhang, X.

    1992-01-01

    The implications of a recently indicated increase in τ lifetime are discussed. It is stressed that the available experimental constraints (from δρ,ε 3 , and N ν , etc.) are satisfied most naturally if the indicated τ anomaly is attributed to the mixing of the τ family with a heavy vectorlike family Q L, R ' with masses ∼200 GeV to 2 TeV, which is a doublet of SU(2) R and singlet of SU(2) L , rather than with a heavy fourth family with standard chiral couplings. L↔R symmetry would imply that Q L, R ' is accompanied by the parity-conjugate family Q L, R which is a doublet of SU(2) L and singlet of SU(2) R . Two such vectorlike families, together with an increase in τ τ , are, in fact, crucial predictions of a recently proposed supersymmetric composite model that possesses many attractive features, in particular, explanations of the origin of diverse scales and family replication. In the context of such a model, it is noted that 3 an increase in τ τ due to mixing involving vectorlike families will necessarily imply a correlated decrease in neutrino counting N ν from the CERN e + e- collider LEP from 3. Such a decrease in N ν would be absent, however, if the τ anomaly is attributed to a mixing involving a standard fourth family with chiral couplings. Because of the seesaw nature of the mass matrix of the three chiral and two vectorlike families, that arises naturally in the model, departures from universality in the first two families as well as in bar bb and τ + τ - channels (linked to down flavors) are strongly suppressed, in accord with observations

  11. First branchial cleft anomaly.

    Science.gov (United States)

    Al-Fallouji, M. A.; Butler, M. F.

    1983-01-01

    A 15-year-old girl presented with a cystic swelling since birth behind the ramus of the right mandible and diagnosed clinically as a dermoid cyst. Surgical exploration, however, showed that it was closely related to the external auditory canal, with an extension running medially behind the parotid gland and ending in the bony middle ear. The facial nerve was closely related to the deep part of the cyst. Such an anatomical position indicates that this was a first branchial cleft anomaly. Surgical excision of the cyst was performed. PMID:6622327

  12. An application of liquid sublayer dryout mechanism to the prediction of critical heat flux under low pressure and low velocity conditions in round tubes

    International Nuclear Information System (INIS)

    Lee, Kwang-Won; Yang, Jae-Young; Baik, Se-Jin

    1997-01-01

    Based on several experimental evidences for nucleate boiling in annular film and the existence of residual liquid film flow rate at the critical heat flux (CHF) location, the liquid sublayer dryout (LSD) mechanism under annular film is firstly introduced to evaluate the CHF data at low pressure and low velocity (LPLV) conditions, which would not be predicted by a normal annular film dryout (AFD) model. In this study, the CHF occurrence due to annular film separation or breaking down is phenomenologically modelled by applying the LSD mechanism to this situation. In this LSD mechanism, the liquid sublayer thickness, the incoming liquid velocity to the liquid sublayer, and the axial distance from the onset of annular flow to the CHF location are used as the phenomena-controlling parameters. From the model validation on the 1406 CHF data points ranging over P = 0.1 - 2 MPa, G = 4 - 499 kg/m 2 s, L/D = 4 - 402, most of CHF data (more than 1000 points) are predicted within ±30% error bounds by the LSD mechanism. However, some calculation results that critical qualities are less than 0.4 are considerably overestimated by this mechanism. These overpredictions seem to be caused by inadequate CHF mechanism classification criteria and an insufficient consideration of the flow instability effect on CHF. Further studies for a new classification criterion screening the CHF data affected by flow instabilities and a new bubble detachment model for LPLV conditions are needed to improve the model accuracy. (author)

  13. Self-healing of low-velocity impact damage in glass fabric/epoxy composites using an epoxy–mercaptan healing agent

    International Nuclear Information System (INIS)

    Yuan, Yan Chao; Qin, Shi Xiang; Ye, Yueping; Chen, Haibin; Wu, Jingshen; Rong, Min Zhi; Zhang, Ming Qiu; Yang, Gui Cheng

    2011-01-01

    Self-healing woven glass fabric-reinforced epoxy composite laminates were made by embedding epoxy- and mercaptan-loaded microcapsules. After being subjected to low-velocity impact, the laminates were able to heal the damage in an autonomic way at room temperature. The healing-induced reduction in the damaged areas was visualized using a scanning acoustic microscope. The rate of damage area reduction, which is closely related to the effect of crack rehabilitation and mechanical recovery, is a function of impact energy, content and size of the healing microcapsules. Minor damage, such as microcracks in the matrix, can be completely repaired by the healing system without manual intervention, including external pressure. Microcapsules with larger size and/or higher concentration are propitious for delivering more healing agent to cracked portions, while imposition of lateral pressure on damaged specimens forces the separated faces to approach each other. Both can improve the rate of damage area reduction in the case of severe damage

  14. Study of Impact Damage in PVA-ECC Beam under Low-Velocity Impact Loading Using Piezoceramic Transducers and PVDF Thin-Film Transducers.

    Science.gov (United States)

    Qi, Baoxin; Kong, Qingzhao; Qian, Hui; Patil, Devendra; Lim, Ing; Li, Mo; Liu, Dong; Song, Gangbing

    2018-02-24

    Compared to conventional concrete, polyvinyl alcohol fiber reinforced engineering cementitious composite (PVA-ECC) offers high-strength, ductility, formability, and excellent fatigue resistance. However, impact-induced structural damage is a major concern and has not been previously characterized in PVA-ECC structures. We investigate the damage of PVA-ECC beams under low-velocity impact loading. A series of ball-drop impact tests were performed at different drop weights and heights to simulate various impact energies. The impact results of PVA-ECC beams were compared with mortar beams. A combination of polyvinylidene fluoride (PVDF) thin-film sensors and piezoceramic-based smart aggregate were used for impact monitoring, which included impact initiation and crack evolution. Short-time Fourier transform (STFT) of the signal received by PVDF thin-film sensors was performed to identify impact events, while active-sensing approach was utilized to detect impact-induced crack evolution by the attenuation of a propagated guided wave. Wavelet packet-based energy analysis was performed to quantify failure development under repeated impact tests.

  15. Einstein, Entropy and Anomalies

    Science.gov (United States)

    Sirtes, Daniel; Oberheim, Eric

    2006-11-01

    This paper strengthens and defends the pluralistic implications of Einstein's successful, quantitative predictions of Brownian motion for a philosophical dispute about the nature of scientific advance that began between two prominent philosophers of science in the second half of the twentieth century (Thomas Kuhn and Paul Feyerabend). Kuhn promoted a monistic phase-model of scientific advance, according to which a paradigm driven `normal science' gives rise to its own anomalies, which then lead to a crisis and eventually a scientific revolution. Feyerabend stressed the importance of pluralism for scientific progress. He rejected Kuhn's model arguing that it fails to recognize the role that alternative theories can play in identifying exactly which phenomena are anomalous in the first place. On Feyerabend's account, Einstein's predictions allow for a crucial experiment between two incommensurable theories, and are an example of an anomaly that could refute the reigning paradigm only after the development of a competitor. Using Kuhn's specification of a disciplinary matrix to illustrate the incommensurability between the two paradigms, we examine the different research strategies available in this peculiar case. On the basis of our reconstruction, we conclude by rebutting some critics of Feyerabend's argument.

  16. Hydrogeophysical exploration of three-dimensional salinity anomalies with the time-domain electromagnetic method (TDEM)

    DEFF Research Database (Denmark)

    Bauer-Gottwein, Peter; Gondwe, Bibi Ruth Neuman; Christiansen, Lars

    2010-01-01

    Delta is presented. Evaporative salt enrichment causes a strong salinity anomaly under the island. We show that the TDEM field data cannot be interpreted in terms of standard one-dimensional layered-earth TDEM models, because of the strongly three-dimensional nature of the salinity anomaly. Three...

  17. Low Risk Anomalies?

    DEFF Research Database (Denmark)

    Schneider, Paul; Wagner, Christian; Zechner, Josef

    This paper shows theoretically and empirically that beta- and volatility-based low risk anomalies are driven by return skewness. The empirical patterns concisely match the predictions of our model that endogenizes the role of skewness for stock returns through default risk. With increasing downside...... risk, the standard capital asset pricing model (CAPM) increasingly overestimates expected equity returns relative to firms' true (skew-adjusted) market risk. Empirically, the profitability of betting against beta/volatility increases with firms' downside risk, and the risk-adjusted return differential...... of betting against beta/volatility among low skew firms compared to high skew firms is economically large. Our results suggest that the returns to betting against beta or volatility do not necessarily pose asset pricing puzzles but rather that such strategies collect premia that compensate for skew risk...

  18. Water radon anomaly fields

    Energy Technology Data Exchange (ETDEWEB)

    Yin, H.

    1980-01-01

    A striking aspect of water radon levels in relation to earthquakes is that before the Tangshan quake there was a remarkable synchronicity of behavior of many wells within 200 km of Tangshan. However, for many wells anomalous values persisted after the earthquake, particularly outside the immediate region of the quake. It is clear that radon may be produced by various processes; some candidates are pressure, shear, vibration, temperature and pressure, mixing of water-bearing strata, breakdown of mineral crystal structure, and the like, although it is not clear which of these are primary. It seems that a possible explanation of the persistence of the anomaly in the case of Tangshan may be that the earthquake released strain in the vicinity of Tangshan but increased it further along the geological structures involved, thus producing a continued radon buildup.

  19. Nolen-Schiffer anomaly

    International Nuclear Information System (INIS)

    Pieper, S.C.; Wiringa, R.B.

    1995-01-01

    The Argonne v 18 potential contains a detailed treatment of the pp, pn and nn electromagnetic potential, including Coulomb, vacuum polarization, Darwin Foldy and magnetic moment terms, all with suitable form factors and was fit to pp and pn data using the appropriate nuclear masses. In addition, it contains a nuclear charge-symmetry breaking (CSB) term adjusted to reproduce the difference in the experimental pp and nn scattering lengths. We have used these potential terms to compute differences in the binding energies of mirror isospin-1/2 nuclei (Nolen-Schiffer [NS] anomaly). Variational Monte Carlo calculations for the 3 He- 3 H system and cluster variational Monte Carlo for the 15 O- 15 N and 17 F- 17 O systems were made. In the first case, the best variational wave function for the A = 3 nuclei was used. However, because our 16 O wave function does not reproduce accurately the 16 O rms radius, to which the NS anomaly is very sensitive, we adjusted the A = 15 and A = 17 wave functions to reproduce the experimental density profiles. Our computed energy differences for these three systems are 0.757 ± .001, 3.544 ± .018 and 3.458 ± .040 MeV respectively, which are to be compared with the experimental differences of 0.764, 3.537, and 3.544 MeV. Most of the theoretical uncertainties are due to uncertainties in the experimental rms radii. The nuclear CSB potential contributes 0.066, 0.188, and 0.090 MeV to these totals. We also attempted calculations for A = 39 and A = 41. However, in these cases, the experimental uncertainties in the rms radius make it impossible to extract useful information about the contribution of the nuclear CSB potential

  20. An utilization of liquid sublayer dryout mechanism in predicting critical heat flux under low pressure and low velocity conditions in round tubes

    International Nuclear Information System (INIS)

    Lee, Kwang-Won; Baik, Se-Jin; Ro, Tae-Sun

    2000-01-01

    From a theoretical assessment of extensive critical heat flux (CHF) data under low pressure and low velocity (LPLV) conditions, it was found out that lots of CHF data would not be well predicted by a normal annular film dryout (AFD) mechanism, although their flow patterns were identified as annular-mist flow. To predict these CHF data, a liquid sublayer dryout (LSD) mechanism has been newly utilized in developing the mechanistic CHF model based on each identified CHF mechanism. This mechanism postulates that the CHF occurrence is caused by dryout of the thin liquid sublayer resulting from the annular film separation or breaking down due to nucleate boiling in annular film or hydrodynamic fluctuation. In principle, this mechanism well supports the experimental evidence of residual film flow rate at the CHF location, which can not be explained by the AFD mechanism. For a comparative assessment of each mechanism, the CHF model based on the LSD mechanism is developed together with that based on the AFD mechanism. The validation of these models is performed on the 1406 CHF data points ranging over P=0.1-2 MPa, G=4-499 kg m -2 s -1 , L/D=4-402. This model validation shows that 1055 and 231 CHF data are predicted within ±30 error bound by the LSD mechanism and the AFD mechanism, respectively. However, some CHF data whose critical qualities are <0.4 or whose tube length-to-diameter ratios are <70 are considerably overestimated by the CHF model based on the LSD mechanism. These overestimations seem to be caused by an inadequate CHF mechanism classification and an insufficient consideration of the flow instability effect on CHF. Further studies for a new classification criterion screening the CHF data affected by flow instabilities as well as a new bubble detachment model for LPLV conditions, are needed to improve the model accuracy.

  1. The effect of interlaminar graphene nano-sheets reinforced e-glass fiber/ epoxy on low velocity impact response of a composite plate

    Science.gov (United States)

    Al-Maharma, A. Y.; Sendur, P.

    2018-05-01

    In this study, we compare the inter-laminar effect of graphene nano-sheets (GNSs) and CNTs on the single and multiple dynamic impact response of E-glass fiber reinforced epoxy composite (GFEP). In the comparisons, raw GFEP composite is used as baseline for quantifying the improvement on the dynamic impact response. For that purpose, finite element based models are developed for GNSs on GFEP, graphene coating on glass fibers, inter-laminar composite of CNTs reinforced polyester at 7.5 vol%, and combinations of all these reinforcements. Comparisons are made on three metrics: (i) total deformation, (ii) the contact force, and (iii) internal energy of the composite plate. The improvement on axial modulus (E1) of GFEP reinforced with one layer of GNS (0.5 wt%) without polyester at lamination sequence of [0]8 is 29.4%, which is very close to the improvement of 31% on storage modulus for multi-layer graphene with 0.5 wt% reinforced E-glass/epoxy composite at room temperature. Using three GNSs (1.5 wt%) reinforced polyester composite as interlaminar layer results in an improvement of 57.1% on E1 of GFEP composite. The simulation results reveal that the interlaminar three GNSs/polyester composite at mid-plane of GFEP laminated composite can significantly improve the dynamic impact resistance of GFEP structure compared to the other aforementioned structural reinforcements. Reinforcing GFEP composite with three layers of GNSs/polyester composite at mid-plane results in an average of 35% improvement on the dynamic impact resistance for healthy and damaged composite plate under low velocity impacts of single and multiple steel projectiles. This model can find application in various areas including structural health monitoring, fire retardant composite, and manufacturing of high strength and lightweight mechanical parts such as gas tank, aircraft wings and wind turbine blades.

  2. Axial anomaly at finite temperature

    International Nuclear Information System (INIS)

    Chaturvedi, S.; Gupte, Neelima; Srinivasan, V.

    1985-01-01

    The Jackiw-Bardeen-Adler anomaly for QED 4 and QED 2 are calculated at finite temperature. It is found that the anomaly is independent of temperature. Ishikawa's method [1984, Phys. Rev. Lett. vol. 53 1615] for calculating the quantised Hall effect is extended to finite temperature. (author)

  3. Novel topological invariants and anomalies

    International Nuclear Information System (INIS)

    Hirayama, M.; Sugimasa, N.

    1987-01-01

    It is shown that novel topological invariants are associated with a class of Dirac operators. Trace formulas which are similar to but different from Callias's formula are derived. Implications of these topological invariants to anomalies in quantum field theory are discussed. A new class of anomalies are calculated for two models: one is two dimensional and the other four dimensional

  4. Anomaly mediated supersymmetry breaking in four dimensions, naturally

    International Nuclear Information System (INIS)

    Luty, Markus A.; Sundrum, Raman

    2003-01-01

    We present a simple four-dimensional model in which anomaly mediated supersymmetry breaking naturally dominates. The central ingredient is that the hidden sector is near a strongly coupled infrared fixed point for several decades of energy below the Planck scale. Strong renormalization effects then sequester the hidden sector from the visible sector. Supersymmetry is broken dynamically and requires no small input parameters. The model provides a natural and economical explanation of the hierarchy between the supersymmetry-breaking scale and the Planck scale, while allowing anomaly mediation to address the phenomenological challenges posed by weak scale supersymmetry. In particular, flavor-changing neutral currents are naturally near their experimental limits

  5. Gravity anomalies without geomagnetic disturbances interfere with pigeon homing--a GPS tracking study.

    Science.gov (United States)

    Blaser, Nicole; Guskov, Sergei I; Entin, Vladimir A; Wolfer, David P; Kanevskyi, Valeryi A; Lipp, Hans-Peter

    2014-11-15

    The gravity vector theory postulates that birds determine their position to set a home course by comparing the memorized gravity vector at the home loft with the local gravity vector at the release site, and that they should adjust their flight course to the gravity anomalies encountered. As gravity anomalies are often intermingled with geomagnetic anomalies, we released experienced pigeons from the center of a strong circular gravity anomaly (25 km diameter) not associated with magnetic anomalies and from a geophysical control site, equidistant from the home loft (91 km). After crossing the border zone of the anomaly--expected to be most critical for pigeon navigation--they dispersed significantly more than control birds, except for those having met a gravity anomaly en route. These data increase the credibility of the gravity vector hypothesis. © 2014. Published by The Company of Biologists Ltd.

  6. Anomalies in instanton calculus

    International Nuclear Information System (INIS)

    Anselmi, D.

    1995-01-01

    I develop a formalism for solving topological field theories explicitly, in the case when the explicit expression of the instantons is known. I solve topological Yang-Mills theory with the k=1 instanton of Belavin et al. and topological gravity with the Eguchi-Hanson instanton. It turns out that naively empty theories are indeed nontrivial. Many unexpected interesting hidden quantities (punctures, contact terms, nonperturbative anomalies with or without gravity) are revealed. Topological Yang-Mills theory with G=SU(2) is not just Donaldson theory, but contains a certain link theory. Indeed, local and non-local observables have the property of marking cycles. Moreover, from topological gravity one learns that an object can be considered BRST exact only if it is so all over the moduli space M , boundary included. Being BRST exact in any interior point of M is not sufficient to make an amplitude vanish. Presumably, recursion relations and hierarchies can be found to solve topological field theories in four dimensions, in particular topological Yang-Mills theory with G=SU(2) on R 4 and topological gravity with the full set of asymptotically locally Euclidean manifolds. ((orig.))

  7. Dispersion Energy Analysis of Rayleigh and Love Waves in the Presence of Low-Velocity Layers in Near-Surface Seismic Surveys

    Science.gov (United States)

    Mi, Binbin; Xia, Jianghai; Shen, Chao; Wang, Limin

    2018-03-01

    High-frequency surface-wave analysis methods have been effectively and widely used to determine near-surface shear (S) wave velocity. To image the dispersion energy and identify different dispersive modes of surface waves accurately is one of key steps of using surface-wave methods. We analyzed the dispersion energy characteristics of Rayleigh and Love waves in near-surface layered models based on numerical simulations. It has been found that if there is a low-velocity layer (LVL) in the half-space, the dispersion energy of Rayleigh or Love waves is discontinuous and ``jumping'' appears from the fundamental mode to higher modes on dispersive images. We introduce the guided waves generated in an LVL (LVL-guided waves, a trapped wave mode) to clarify the complexity of the dispersion energy. We confirm the LVL-guided waves by analyzing the snapshots of SH and P-SV wavefield and comparing the dispersive energy with theoretical values of phase velocities. Results demonstrate that LVL-guided waves possess energy on dispersive images, which can interfere with the normal dispersion energy of Rayleigh or Love waves. Each mode of LVL-guided waves having lack of energy at the free surface in some high frequency range causes the discontinuity of dispersive energy on dispersive images, which is because shorter wavelengths (generally with lower phase velocities and higher frequencies) of LVL-guided waves cannot penetrate to the free surface. If the S wave velocity of the LVL is higher than that of the surface layer, the energy of LVL-guided waves only contaminates higher mode energy of surface waves and there is no interlacement with the fundamental mode of surface waves, while if the S wave velocity of the LVL is lower than that of the surface layer, the energy of LVL-guided waves may interlace with the fundamental mode of surface waves. Both of the interlacements with the fundamental mode or higher mode energy may cause misidentification for the dispersion curves of surface

  8. Global aspects of gauge anomalies

    International Nuclear Information System (INIS)

    Zhang, H.

    1988-01-01

    This dissertation discusses the global aspects of gauge anomalies in even dimensions. After a very brief description of local gauge anomalies, the possible global gauge anomalies for various gauge theories are discussed using homotopy theory. One of the main results obtained in a general formula for the SU(n - k) global gauge anomaly coefficient in arbitrary 2n dimensions. The result is expressed in terms of the James number of the Stiefel manifold SU(n + 1)/SU(n - k) and the generalized Dynkin indices. From this, the possibilities of SU(n), SU(n - 1), and SU(2) global gauge anomalies in arbitrary 2n dimensions have been determined. We have also determined the possibilities of global gauge anomalies for the gauge groups SP(2N) and SO(N) in certain general dimensions, as well as for the exceptional gauge groups in specific dimensions. Moreover, several general propositions are formulated and proved which are very useful in the study of global gauge anomalies

  9. An introduction to gravitational anomalies

    International Nuclear Information System (INIS)

    Alvarez-Gaume', L.

    1984-01-01

    The outline of these lectures is as follows: We will first analyze the abelian anomaly from the point of view of the Atiyah-Singer index theorem. This is clearly not the first time that this analysis has been carried out, but it will give us a chance of introducing a general method of computing anomalies based on supersymmetric quantum mechanics. Then we will present the general strategy for identifying and computing the anomalies in the energy-momentum tensor and what can be learned from them

  10. Gravitational Anomaly and Transport Phenomena

    International Nuclear Information System (INIS)

    Landsteiner, Karl; Megias, Eugenio; Pena-Benitez, Francisco

    2011-01-01

    Quantum anomalies give rise to new transport phenomena. In particular, a magnetic field can induce an anomalous current via the chiral magnetic effect and a vortex in the relativistic fluid can also induce a current via the chiral vortical effect. The related transport coefficients can be calculated via Kubo formulas. We evaluate the Kubo formula for the anomalous vortical conductivity at weak coupling and show that it receives contributions proportional to the gravitational anomaly coefficient. The gravitational anomaly gives rise to an anomalous vortical effect even for an uncharged fluid.

  11. Anomalies in Flavour physics

    CERN Document Server

    Chrzaszcz, Marcin Jakub

    2015-01-01

    LHCb is measuring more and more deviations in electroweak penguin measurements, both in the angular observables (like P5') and the branching fractions. Furthermore, there are strong hints of lepton universality breaking in semileptonic decays. This talk aims to present the results of these measurements and the implications for new physics. A result of a global fit will be presented.

  12. Interior Alaska Bouguer Gravity Anomaly

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1 kilometer Complete Bouguer Anomaly gravity grid of interior Alaska. All grid cells within the rectangular data area (from 61 to 66 degrees North latitude and...

  13. Interior Alaska Bouguer Gravity Anomaly

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1 kilometer Complete Bouguer Anomaly gravity grid of interior Alaska. Only those grid cells within 10 kilometers of a gravity data point have gravity values....

  14. On renormalization of axial anomaly

    International Nuclear Information System (INIS)

    Efremov, A.V.; Teryaev, O.V.

    1989-01-01

    It is shown that multiplicative renormalization of the axial singlet current results in renormalization of the axial anomaly in all orders of perturbation theory. It is a necessary condition for the Adler - Bardeen theorem being valid. 10 refs.; 2 figs

  15. Situs anomalies on prenatal MRI

    International Nuclear Information System (INIS)

    Nemec, Stefan F.; Brugger, Peter C.; Nemec, Ursula; Bettelheim, Dieter; Kasprian, Gregor; Amann, Gabriele; Rimoin, David L.; Graham, John M.; Prayer, Daniela

    2012-01-01

    Objective: Situs anomalies refer to an abnormal organ arrangement, which may be associated with severe errors of development. Due regard being given to prenatal magnetic resonance imaging (MRI) as an adjunct to ultrasonography (US), this study sought to demonstrate the in utero visualization of situs anomalies on MRI, compared to US. Materials and methods: This retrospective study included 12 fetuses with situs anomalies depicted on fetal MRI using prenatal US as a comparison modality. With an MRI standard protocol, the whole fetus was assessed for anomalies, with regard to the position and morphology of the following structures: heart; venous drainage and aorta; stomach and intestines; liver and gallbladder; and the presence and number of spleens. Results: Situs inversus totalis was found in 3/12 fetuses; situs inversus with levocardia in 1/12 fetuses; situs inversus abdominis in 2/12 fetuses; situs ambiguous with polysplenia in 3/12 fetuses, and with asplenia in 2/12 fetuses; and isolated dextrocardia in 1/12 fetuses. Congenital heart defects (CHDs), vascular anomalies, and intestinal malrotations were the most frequent associated malformations. In 5/12 cases, the US and MRI diagnoses were concordant. Compared to US, in 7/12 cases, additional MRI findings specified the situs anomaly, but CHDs were only partially visualized in six cases. Conclusions: Our initial MRI results demonstrate the visualization of situs anomalies and associated malformations in utero, which may provide important information for perinatal management. Using a standard protocol, MRI may identify additional findings, compared to US, which confirm and specify the situs anomaly, but, with limited MRI visualization of fetal CHDs.

  16. Dimensional reduction in anomaly mediation

    International Nuclear Information System (INIS)

    Boyda, Ed; Murayama, Hitoshi; Pierce, Aaron

    2002-01-01

    We offer a guide to dimensional reduction in theories with anomaly-mediated supersymmetry breaking. Evanescent operators proportional to ε arise in the bare Lagrangian when it is reduced from d=4 to d=4-2ε dimensions. In the course of a detailed diagrammatic calculation, we show that inclusion of these operators is crucial. The evanescent operators conspire to drive the supersymmetry-breaking parameters along anomaly-mediation trajectories across heavy particle thresholds, guaranteeing the ultraviolet insensitivity

  17. Aeromagnetic anomalies over faulted strata

    Science.gov (United States)

    Grauch, V.J.S.; Hudson, Mark R.

    2011-01-01

    High-resolution aeromagnetic surveys are now an industry standard and they commonly detect anomalies that are attributed to faults within sedimentary basins. However, detailed studies identifying geologic sources of magnetic anomalies in sedimentary environments are rare in the literature. Opportunities to study these sources have come from well-exposed sedimentary basins of the Rio Grande rift in New Mexico and Colorado. High-resolution aeromagnetic data from these areas reveal numerous, curvilinear, low-amplitude (2–15 nT at 100-m terrain clearance) anomalies that consistently correspond to intrasedimentary normal faults (Figure 1). Detailed geophysical and rock-property studies provide evidence for the magnetic sources at several exposures of these faults in the central Rio Grande rift (summarized in Grauch and Hudson, 2007, and Hudson et al., 2008). A key result is that the aeromagnetic anomalies arise from the juxtaposition of magnetically differing strata at the faults as opposed to chemical processes acting at the fault zone. The studies also provide (1) guidelines for understanding and estimating the geophysical parameters controlling aeromagnetic anomalies at faulted strata (Grauch and Hudson), and (2) observations on key geologic factors that are favorable for developing similar sedimentary sources of aeromagnetic anomalies elsewhere (Hudson et al.).

  18. Space weather and space anomalies

    Directory of Open Access Journals (Sweden)

    L. I. Dorman

    2005-11-01

    Full Text Available A large database of anomalies, registered by 220 satellites in different orbits over the period 1971-1994 has been compiled. For the first time, data from 49 Russian Kosmos satellites have been included in a statistical analysis. The database also contains a large set of daily and hourly space weather parameters. A series of statistical analyses made it possible to quantify, for different satellite orbits, space weather conditions on the days characterized by anomaly occurrences. In particular, very intense fluxes (>1000 pfu at energy >10 MeV of solar protons are linked to anomalies registered by satellites in high-altitude (>15000 km, near-polar (inclination >55° orbits typical for navigation satellites, such as those used in the GPS network, NAVSTAR, etc. (the rate of anomalies increases by a factor ~20, and to a much smaller extent to anomalies in geostationary orbits, (they increase by a factor ~4. Direct and indirect connections between anomaly occurrence and geomagnetic perturbations are also discussed.

  19. Road Anomalies Detection System Evaluation.

    Science.gov (United States)

    Silva, Nuno; Shah, Vaibhav; Soares, João; Rodrigues, Helena

    2018-06-21

    Anomalies on road pavement cause discomfort to drivers and passengers, and may cause mechanical failure or even accidents. Governments spend millions of Euros every year on road maintenance, often causing traffic jams and congestion on urban roads on a daily basis. This paper analyses the difference between the deployment of a road anomalies detection and identification system in a “conditioned” and a real world setup, where the system performed worse compared to the “conditioned” setup. It also presents a system performance analysis based on the analysis of the training data sets; on the analysis of the attributes complexity, through the application of PCA techniques; and on the analysis of the attributes in the context of each anomaly type, using acceleration standard deviation attributes to observe how different anomalies classes are distributed in the Cartesian coordinates system. Overall, in this paper, we describe the main insights on road anomalies detection challenges to support the design and deployment of a new iteration of our system towards the deployment of a road anomaly detection service to provide information about roads condition to drivers and government entities.

  20. Pre-seismic anomalies from optical satellite observations: a review

    Science.gov (United States)

    Jiao, Zhong-Hu; Zhao, Jing; Shan, Xinjian

    2018-04-01

    Detecting various anomalies using optical satellite data prior to strong earthquakes is key to understanding and forecasting earthquake activities because of its recognition of thermal-radiation-related phenomena in seismic preparation phases. Data from satellite observations serve as a powerful tool in monitoring earthquake preparation areas at a global scale and in a nearly real-time manner. Over the past several decades, many new different data sources have been utilized in this field, and progressive anomaly detection approaches have been developed. This paper reviews the progress and development of pre-seismic anomaly detection technology in this decade. First, precursor parameters, including parameters from the top of the atmosphere, in the atmosphere, and on the Earth's surface, are stated and discussed. Second, different anomaly detection methods, which are used to extract anomalous signals that probably indicate future seismic events, are presented. Finally, certain critical problems with the current research are highlighted, and new developing trends and perspectives for future work are discussed. The development of Earth observation satellites and anomaly detection algorithms can enrich available information sources, provide advanced tools for multilevel earthquake monitoring, and improve short- and medium-term forecasting, which play a large and growing role in pre-seismic anomaly detection research.

  1. Spontaneous breaking of conformal invariance and trace anomaly matching

    International Nuclear Information System (INIS)

    Schwimmer, A.; Theisen, S.

    2011-01-01

    We argue that when conformal symmetry is spontaneously broken the trace anomalies in the broken and unbroken phases are matched. This puts strong constraints on the various couplings of the dilaton. Using the uniqueness of the effective action for the Goldstone supermultiplet for broken N=1 superconformal symmetry the dilaton effective action is calculated.

  2. Mapping Shear-wave Velocity Structures of the "African Anomaly" Along a Northwest to Southeast Arc From New Zealand to the Mid-Atlantic Ridge

    Science.gov (United States)

    Frodsham, A. E.; Wen, L.

    2006-12-01

    A previous study [Wang and Wen, 2006] investigated the geometry and shear velocity structure of the "African Anomaly" along a great circle arc from the East Pacific Rise to the Japan Sea, and concluded the anomaly extends 1300 km above the core-mantle boundary, that the sides of the anomaly slope towards the apex and has velocity deviations of -5% in the base and -2% to -3% in the mid-lower mantle. Wang and Wen [2004] also reported on the very low velocity province that forms the base of the "African Anomaly" and its lateral extent, but the northern edge of the anomaly was poorly constrained because of the nature of the seismic data. In this presentation we focus on the nature of the anomaly in a cross-section of the mantle along a great arc, from New Zealand, to the Mid-Atlantic Ridge off the coast of Newfoundland, centered over the anomaly. In particular, we focus on the northern edge of the "African Anomaly" where a paucity of large, deep focus earthquakes makes seismic arrivals from the northwest difficult to analyze. We map the lateral extent, thickness, and shear velocity structures of the "African Anomaly" on the basis of forward travel time and waveform modeling of direct S, ScS, and SKS waves. Seismic data used in this study were collected from PASSCAL arrays: KAAPVAAL seismic array (operating years 1997-1999), Tanzania seismic array (1994- 1995), Ethiopia/Kenya seismic array (2000-2002), and the Global Seismographic Network (1994-2002). We minimize uncertainty from earthquake mislocation by relocation of the earthquakes using a global tomographic shear wave velocity model and also correct for heterogeneities outside the anomaly. We explore various methods of data processing, such as frequency filtration, low fold stacking, and cross correlation, to best interpret the arrival times of the various seismic phases and constrain the nature of the "African Anomaly" along a northwest to southeast cross-section.

  3. Prenatal sonographic diagnosis of focal musculoskeletal anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jung Kyu; Cho, Jeong Yeon; Lee, Young Ho; Kim, Ei Jeong; Chun, Yi Kyeong [Samsung Cheil Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2002-09-15

    Focal musculoskeletal anomalies are various and may be an isolated finding or may be found in conjunction with numerous associations, including genetic syndromes, Karyotype abnormals, central nervous system anomalies and other general musculoskeletal disorders. Early prenatal diagnosis of these focal musculoskeletal anomalies nor only affects prenatal care and postnatal outcome but also helps in approaching other numerous associated anomalies.

  4. Prenatal sonographic diagnosis of focal musculoskeletal anomalies

    International Nuclear Information System (INIS)

    Ryu, Jung Kyu; Cho, Jeong Yeon; Lee, Young Ho; Kim, Ei Jeong; Chun, Yi Kyeong

    2002-01-01

    Focal musculoskeletal anomalies are various and may be an isolated finding or may be found in conjunction with numerous associations, including genetic syndromes, Karyotype abnormals, central nervous system anomalies and other general musculoskeletal disorders. Early prenatal diagnosis of these focal musculoskeletal anomalies nor only affects prenatal care and postnatal outcome but also helps in approaching other numerous associated anomalies.

  5. Toward Baseline Software Anomalies in NASA Missions

    Science.gov (United States)

    Layman, Lucas; Zelkowitz, Marvin; Basili, Victor; Nikora, Allen P.

    2012-01-01

    In this fast abstract, we provide preliminary findings an analysis of 14,500 spacecraft anomalies from unmanned NASA missions. We provide some baselines for the distributions of software vs. non-software anomalies in spaceflight systems, the risk ratings of software anomalies, and the corrective actions associated with software anomalies.

  6. Coronary Artery Anomalies in Animals

    Directory of Open Access Journals (Sweden)

    Brian A. Scansen

    2017-04-01

    Full Text Available Coronary artery anomalies represent a disease spectrum from incidental to life-threatening. Anomalies of coronary artery origin and course are well-recognized in human medicine, but have received limited attention in veterinary medicine. Coronary artery anomalies are best described in the dog, hamster, and cow though reports also exist in the horse and pig. The most well-known anomaly in veterinary medicine is anomalous coronary artery origin with a prepulmonary course in dogs, which limits treatment of pulmonary valve stenosis. A categorization scheme for coronary artery anomalies in animals is suggested, dividing these anomalies into those of major or minor clinical significance. A review of coronary artery development, anatomy, and reported anomalies in domesticated species is provided and four novel canine examples of anomalous coronary artery origin are described: an English bulldog with single left coronary ostium and a retroaortic right coronary artery; an English bulldog with single right coronary ostium and transseptal left coronary artery; an English bulldog with single right coronary ostium and absent left coronary artery with a prepulmonary paraconal interventricular branch and an interarterial circumflex branch; and a mixed-breed dog with tetralogy of Fallot and anomalous origin of all coronary branches from the brachiocephalic trunk. Coronary arterial fistulae are also described including a coronary cameral fistula in a llama cria and an English bulldog with coronary artery aneurysm and anomalous shunting vessels from the right coronary artery to the pulmonary trunk. These examples are provided with the intent to raise awareness and improve understanding of such defects.

  7. MAGSAT anomaly map and continental drift

    Science.gov (United States)

    Lemouel, J. L. (Principal Investigator); Galdeano, A.; Ducruix, J.

    1981-01-01

    Anomaly maps of high quality are needed to display unambiguously the so called long wave length anomalies. The anomalies were analyzed in terms of continental drift and the nature of their sources is discussed. The map presented confirms the thinness of the oceanic magnetized layer. Continental magnetic anomalies are characterized by elongated structures generally of east-west trend. Paleomagnetic reconstruction shows that the anomalies found in India, Australia, and Antarctic exhibit a fair consistency with the African anomalies. It is also shown that anomalies are locked under the continents and have a fixed geometry.

  8. Analysis of Renal Anomalies in VACTERL Association

    OpenAIRE

    Cunningham, Bridget K.; Khromykh, Alina; Martinez, Ariel F.; Carney, Tyler; Hadley, Donald W.; Solomon, Benjamin D.

    2014-01-01

    VACTERL association refers to a combination of congenital anomalies that can include: Vertebral anomalies, Anal atresia, Cardiac malformations, Tracheo-Esophageal fistula with esophageal atresia, Renal anomalies (typically structural renal anomalies), and Limb anomalies. We conducted a description of a case series to characterize renal findings in a cohort of patients with VACTERL association. Out of the overall cohort, 48 patients (with at least 3 component features of VACTERL and who had ab...

  9. SEISMIC DISCRIMINATION OF THERMAL AND MAGNETIC ANOMALIES IN SUNSPOT UMBRAE

    International Nuclear Information System (INIS)

    Lindsey, C.; Cally, P. S.; Rempel, M.

    2010-01-01

    Efforts to model sunspots based on helioseismic signatures need to discriminate between the effects of (1) a strong magnetic field that introduces time-irreversible, vantage-dependent phase shifts, apparently connected to fast- and slow-mode coupling and wave absorption and (2) a thermal anomaly that includes cool gas extending an indefinite depth beneath the photosphere. Helioseismic observations of sunspots show travel times considerably reduced with respect to equivalent quiet-Sun signatures. Simulations by Moradi and Cally of waves skipping across sunspots with photospheric magnetic fields of order 3 kG show travel times that respond strongly to the magnetic field and relatively weakly to the thermal anomaly by itself. We note that waves propagating vertically in a vertical magnetic field are relatively insensitive to the magnetic field, while remaining highly responsive to the attendant thermal anomaly. Travel-time measurements for waves with large skip distances into the centers of axially symmetric sunspots are therefore a crucial resource for discrimination of the thermal anomaly beneath sunspot umbrae from the magnetic anomaly. One-dimensional models of sunspot umbrae based on compressible-radiative-magnetic-convective simulations such as by Rempel et al. can be fashioned to fit observed helioseismic travel-time spectra in the centers of sunspot umbrae. These models are based on cooling of the upper 2-4 Mm of the umbral subphotosphere with no significant anomaly beneath 4.5 Mm. The travel-time reductions characteristic of these models are primarily a consequence of a Wilson depression resulting from a strong downward buoyancy of the cooled umbral medium.

  10. Signal anomaly detection and characterization

    International Nuclear Information System (INIS)

    Morgenstern, V.M.; Upadhyaya, B.R.; Gloeckler, O.

    1988-08-01

    As part of a comprehensive signal validation system, we have developed a signal anomaly detector, without specifically establishing the cause of the anomaly. A signal recorded from process instrumentation is said to have an anomaly, if during steady-state operation, the deviation in the level of the signal, its root-mean-square (RMS) value, or its statistical distribution changes by a preset value. This deviation could be an unacceptable increase or a decrease in the quantity being monitored. An anomaly in a signal may be characterized by wideband or single-frequency noise, bias error, pulse-type error, nonsymmetric behavior, or a change in the signal bandwidth. Various signatures can be easily computed from data samples and compared against specified threshold values. We want to point out that in real processes, pulses can appear with different time widths, and at different rates of change of the signal. Thus, in characterizing an anomaly as a pulse-type, the fastest pulse width is constrained by the signal sampling interval. For example, if a signal is sampled at 100 Hz, we will not be able to detect pulses occurring at kHz rates. Discussion with utility and Combustion Engineering personnel indicated that it is not practical to detect pulses having a narrow time width. 9 refs., 11 figs., 8 tabs

  11. Radiologic analysis of congenital limb anomalies

    International Nuclear Information System (INIS)

    Chung, Hong Jun; Kim, Ok Hwa; Shinn, Kyung Sub; Kim, Nam Ae

    1994-01-01

    Congenital limb anomalies are manifested in various degree of severity and complexity bearing conclusion for description and nomenclature of each anomaly. We retrospectively analyzed the roentgenograms of congenital limb anomalies for the purpose of further understanding of the radiologic manifestations based on the embryonal defect and also to find the incidence of each anomaly. Total number of the patients was 89 with 137 anomalies. Recently the uniform system of classification for congenital anomalies of the upper limb was adopted by International Federation of Societies for Surgery of the Hand (IFSSH), which were categorized as 7 classifications. We used the IFSSH classification with some modification as 5 classifications; failure of formation of parts, failure of differentiation of parts, duplications, overgrowth and undergrowth. The patients with upper limb anomalies were 65 out of 89(73%), lower limb were 21(24%), and both upper and lower limb anomalies were 3(4%). Failure of formation was seen in 18%, failure of differentiation 39%, duplications 39%, overgrowth 8%, and undergrowth in 12%. Thirty-five patients had more than one anomaly, and 14 patients had intergroup anomalies. The upper limb anomalies were more common than lower limb. Among the anomalies, failure of differentiation and duplications were the most common types of congenital limb anomalies. Patients with failure of formation, failure of differentiation, and undergrowth had intergroup association of anomalies, but duplication and overgrowth tended to be isolated anomalies

  12. String corrections to circular Wilson loop and anomalies

    Science.gov (United States)

    Cagnazzo, Alessandra; Medina-Rincon, Daniel; Zarembo, Konstantin

    2018-02-01

    We study string quantum corrections to the ratio of latitude and circular Wilson loops in N = 4 super-Yang-Mills theory at strong coupling. Conformal gauge for the corresponding minimal surface in AdS5 × S 5 is singular and we show that an IR anomaly associated with the divergence in the conformal factor removes previously reported discrepancy with the exact field-theory result. We also carefully check conformal anomaly cancellation and recalculate fluctuation determinants by directly evaluting phaseshifts for all the fluctuation modes.

  13. Graph anomalies in cyber communications

    Energy Technology Data Exchange (ETDEWEB)

    Vander Wiel, Scott A [Los Alamos National Laboratory; Storlie, Curtis B [Los Alamos National Laboratory; Sandine, Gary [Los Alamos National Laboratory; Hagberg, Aric A [Los Alamos National Laboratory; Fisk, Michael [Los Alamos National Laboratory

    2011-01-11

    Enterprises monitor cyber traffic for viruses, intruders and stolen information. Detection methods look for known signatures of malicious traffic or search for anomalies with respect to a nominal reference model. Traditional anomaly detection focuses on aggregate traffic at central nodes or on user-level monitoring. More recently, however, traffic is being viewed more holistically as a dynamic communication graph. Attention to the graph nature of the traffic has expanded the types of anomalies that are being sought. We give an overview of several cyber data streams collected at Los Alamos National Laboratory and discuss current work in modeling the graph dynamics of traffic over the network. We consider global properties and local properties within the communication graph. A method for monitoring relative entropy on multiple correlated properties is discussed in detail.

  14. Multiple Visceral and Peritoneal Anomalies

    Directory of Open Access Journals (Sweden)

    Gayathri Prabhu S

    2016-07-01

    Full Text Available Visceral and peritoneal anomalies are frequently encountered during cadaveric dissections and surgical procedures of abdomen. A thorough knowledge of the same is required for the success of diagnostic, surgical and radiological procedures of abdomen. We report multiple peritoneal and visceral anomalies noted during dissection classes for medical undergraduates. The anomalies were found in an adult male cadaver aged approximately 70 years. The right iliac fossa was empty due to the sub-hepatic position of caecum and appendix. The sigmoid colon formed an inverted “U” shaped loop above the sacral promontory in the median position. It entered the pelvis from the right side and descended along the lateral wall of the pelvis. The sigmoid mesocolon was attached obliquely to the posterior abdominal wall, just above the sacral promontory. Further there was a cysto-colic fold of peritoneum extending from the right colic flexure. We discuss the clinical significance of the variations.

  15. Strong moduli stabilization and phenomenology

    CERN Document Server

    Dudas, Emilian; Mambrini, Yann; Mustafayev, Azar; Olive, Keith A

    2013-01-01

    We describe the resulting phenomenology of string theory/supergravity models with strong moduli stabilization. The KL model with F-term uplifting, is one such example. Models of this type predict universal scalar masses equal to the gravitino mass. In contrast, A-terms receive highly suppressed gravity mediated contributions. Under certain conditions, the same conclusion is valid for gaugino masses, which like A-terms, are then determined by anomalies. In such models, we are forced to relatively large gravitino masses (30-1000 TeV). We compute the low energy spectrum as a function of m_{3/2}. We see that the Higgs masses naturally takes values between 125-130 GeV. The lower limit is obtained from the requirement of chargino masses greater than 104 GeV, while the upper limit is determined by the relic density of dark matter (wino-like).

  16. Branchial anomalies: diagnosis and management.

    Science.gov (United States)

    Prasad, Sampath Chandra; Azeez, Arun; Thada, Nikhil Dinaker; Rao, Pallavi; Bacciu, Andrea; Prasad, Kishore Chandra

    2014-01-01

    Objective. To find out the incidence of involvement of individual arches, anatomical types of lesions, the age and sex incidence, the site and side of predilection, the common clinical features, the common investigations, treatment, and complications of the different anomalies. Setting. Academic Department of Otolaryngology, Head and Neck Surgery. Design. A 10 year retrospective study. Participants. 30 patients with clinically proven branchial anomalies including patients with bilateral disease totaling 34 lesions. Main Outcome Measures. The demographical data, clinical features, type of branchial anomalies, and the management details were recorded and analyzed. Results and Observations. The mean age of presentation was 18.67 years. Male to female sex ratio was 1.27 : 1 with a male preponderance. Of the 34 lesions, maximum incidence was of second arch anomalies (50%) followed by first arch. We had two cases each of third and fourth arch anomalies. Only 1 (3.3%) patients of the 30 presented with lesion at birth. The most common pathological type of lesions was fistula (58.82%) followed by cyst. 41.18% of the lesions occurred on the right side. All the patients underwent surgical excision. None of our patients had involvement of facial nerve in first branchial anomaly. All patients had tracts going superficial to the facial nerve. Conclusion. Confirming the extent of the tract is mandatory before any surgery as these lesions pass in relation to some of the most vital structures of the neck. Surgery should always be the treatment option. injection of dye, microscopic removal and inclusion of surrounding tissue while excising the tract leads to a decreased incidence of recurrence.

  17. Branchial Anomalies: Diagnosis and Management

    Science.gov (United States)

    Azeez, Arun; Thada, Nikhil Dinaker; Rao, Pallavi; Prasad, Kishore Chandra

    2014-01-01

    Objective. To find out the incidence of involvement of individual arches, anatomical types of lesions, the age and sex incidence, the site and side of predilection, the common clinical features, the common investigations, treatment, and complications of the different anomalies. Setting. Academic Department of Otolaryngology, Head and Neck Surgery. Design. A 10 year retrospective study. Participants. 30 patients with clinically proven branchial anomalies including patients with bilateral disease totaling 34 lesions. Main Outcome Measures. The demographical data, clinical features, type of branchial anomalies, and the management details were recorded and analyzed. Results and Observations. The mean age of presentation was 18.67 years. Male to female sex ratio was 1.27 : 1 with a male preponderance. Of the 34 lesions, maximum incidence was of second arch anomalies (50%) followed by first arch. We had two cases each of third and fourth arch anomalies. Only 1 (3.3%) patients of the 30 presented with lesion at birth. The most common pathological type of lesions was fistula (58.82%) followed by cyst. 41.18% of the lesions occurred on the right side. All the patients underwent surgical excision. None of our patients had involvement of facial nerve in first branchial anomaly. All patients had tracts going superficial to the facial nerve. Conclusion. Confirming the extent of the tract is mandatory before any surgery as these lesions pass in relation to some of the most vital structures of the neck. Surgery should always be the treatment option. injection of dye, microscopic removal and inclusion of surrounding tissue while excising the tract leads to a decreased incidence of recurrence. PMID:24772172

  18. Supersymmetric regulators and supercurrent anomalies

    International Nuclear Information System (INIS)

    Majumdar, P.; Poggio, E.C.; Schnitzer, H.J.

    1980-01-01

    The supercurrent anomalies of the supercurrent deltasub(μ) of the supersymmetric Yang-Mills theory in Wess-Zumino gauge are computed using the supersymmetric dimensional regulator of Siegel. It is shown that γsub(μ)deltasup(μ) = 0 and deltasub(μ)deltasup(μ) unequal 0 in agreement with an earlier calculation based on the Adler-Rosenberg method. The problem of exhibiting the chiral anomaly and a regulator for local supersymmetry suggests that the interpretation of dimensional reduction in component language is incomplete. (orig.)

  19. Anomalies, Beta Functions, and GUT's

    International Nuclear Information System (INIS)

    Aranda, Alfredo; Diaz-Cruz, J. L.; Rojas, Alma D.

    2009-01-01

    In the framework of supersymmetric Grand Unified theories it is possible to extend the minimal Higgs sectors of the models by introducing high dimension (anomaly free) representations. For example, in the minimal SU(5) supersymmetric Grand Unified Model, this is done to obtain phenomenological viable fermion mass relations and/or to solve the doublet-triplet splitting problem. In this work we explore models with different anomaly free combinations of SU(5) representations motivated by the flavour problem as well as their effect on perturbative validity of the gauge coupling evolution.

  20. Review on possible gravitational anomalies

    International Nuclear Information System (INIS)

    Amador, Xavier E

    2005-01-01

    This is an updated introductory review of 2 possible gravitational anomalies that has attracted part of the Scientific community: the Allais effect that occur during solar eclipses, and the Pioneer 10 spacecraft anomaly, experimented also by Pioneer 11 and Ulysses spacecrafts. It seems that, to date, no satisfactory conventional explanation exist to these phenomena, and this suggests that possible new physics will be needed to account for them. The main purpose of this review is to announce 3 other new measurements that will be carried on during the 2005 solar eclipses in Panama and Colombia (Apr. 8) and in Portugal (Oct.15)

  1. Anomaly Detection in Gas Turbine Fuel Systems Using a Sequential Symbolic Method

    Directory of Open Access Journals (Sweden)

    Fei Li

    2017-05-01

    Full Text Available Anomaly detection plays a significant role in helping gas turbines run reliably and economically. Considering the collective anomalous data and both sensitivity and robustness of the anomaly detection model, a sequential symbolic anomaly detection method is proposed and applied to the gas turbine fuel system. A structural Finite State Machine is used to evaluate posterior probabilities of observing symbolic sequences and the most probable state sequences they may locate. Hence an estimation-based model and a decoding-based model are used to identify anomalies in two different ways. Experimental results indicate that both models have both ideal performance overall, but the estimation-based model has a strong robustness ability, whereas the decoding-based model has a strong accuracy ability, particularly in a certain range of sequence lengths. Therefore, the proposed method can facilitate well existing symbolic dynamic analysis- based anomaly detection methods, especially in the gas turbine domain.

  2. Beta decay anomalies and the 17-keV conundrum

    International Nuclear Information System (INIS)

    Hime, A.

    1993-01-01

    Recent developments in pursuance of the 17-keV neutrino are reviewed. Several different experiments found anomalies in β decay spectra which were consistently interpreted as evidence for a heavy neutrino. On the other hand, recent null results definitively rule out the existence of a 17-keV neutrino, as well as escaping criticisms applicable to earlier experiments. While missing links remain, it seems that any strong evidence for a 17-keV neutrino has vanished. Specifically, the anomalies observed in 35 S and 63 Ni spectra at Oxford can be reinterpreted in terms of electron scattering effects. In addition, the discrepancy amongst internal bremsstrahlung measurements has an instrumental origin, and recent results disfavour a 17-keV neutrino. Anomalies persist in the low energy region of the tritium spectrum which deserve further investigation

  3. Oropharyngeal trauma mimicking a first branchial cleft anomaly.

    Science.gov (United States)

    Larem, Aisha; Sheikh, Rashid; Al Qahtani, Abdulsalam; Khais, Frat; Ganesan, Shanmugam; Haidar, Hassan

    2016-06-01

    We present a unique and challenging case of a remnant foreign body that presented to us in a child disguised as a strongly suspected congenital branchial cleft anomaly. This case entailed oropharyngeal trauma, with a delayed presentation as a retroauricular cyst accompanied by otorrhea that mimicked the classic presentation of an infected first branchial cleft anomaly. During surgical excision of the presumed branchial anomaly, a large wooden stick was found in the tract. The diagnostic and therapeutic obstacles in the management of such cases are highlighted. In addition to exploring the existing literature, we retrospectively analyzed a plausible explanation of the findings of this case. Laryngoscope, 126:E224-E226, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  4. Ferromagnetic Spin Coupling as the Origin of 0.7 Anomaly in Quantum Point Contacts

    OpenAIRE

    Aryanpour, K.; Han, J. E.

    2008-01-01

    We study one-dimensional itinerant electron models with ferromagnetic coupling to investigate the origin of 0.7 anomaly in quantum point contacts. Linear conductance calculations from the quantum Monte Carlo technique for spin interactions of different spatial range suggest that $0.7(2e^{2}/h)$ anomaly results from a strong interaction of low-density conduction electrons to ferromagnetic fluctuations formed across the potential barrier. The conductance plateau appears due to the strong incohe...

  5. Global gravitational anomalies and transport

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhury, Subham Dutta; David, Justin R. [Centre for High Energy Physics, Indian Institute of Science,C. V. Raman Avenue, Bangalore 560012 (India)

    2016-12-21

    We investigate the constraints imposed by global gravitational anomalies on parity odd induced transport coefficients in even dimensions for theories with chiral fermions, gravitinos and self dual tensors. The η-invariant for the large diffeomorphism corresponding to the T transformation on a torus constraints the coefficients in the thermal effective action up to mod 2. We show that the result obtained for the parity odd transport for gravitinos using global anomaly matching is consistent with the direct perturbative calculation. In d=6 we see that the second Pontryagin class in the anomaly polynomial does not contribute to the η-invariant which provides a topological explanation of this observation in the ‘replacement rule’. We then perform a direct perturbative calculation for the contribution of the self dual tensor in d=6 to the parity odd transport coefficient using the Feynman rules proposed by Gaumé and Witten. The result for the transport coefficient agrees with that obtained using matching of global anomalies.

  6. Sharing AIS Related Anomalies (SARA)

    Science.gov (United States)

    2016-03-01

    78 6.3.7 SQL Versus NoSQL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 6.4 Data Processing...43 6.1 Overview of SQL and NoSQL differences, from [56]. . . . . . . . . . . . . . . . . . 82 A.1 Description of the ship anomaly upload use...constraints must be considered. These requirements, however, can only be defined when lower level implementation decisions, such as SQL versus NoSQL

  7. Covariant Gauss law commutator anomaly

    International Nuclear Information System (INIS)

    Dunne, G.V.; Trugenberger, C.A.; Massachusetts Inst. of Tech., Cambridge

    1990-01-01

    Using a (fixed-time) hamiltonian formalism we derive a covariant form for the anomaly in the commutator algebra of Gauss law generators for chiral fermions interacting with a dynamical non-abelian gauge field in 3+1 dimensions. (orig.)

  8. Branchial cleft anomalies: CT evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Seok, Eul Hye; Park, Chan Sup [College of Medicine, Inha University, Seongnam (Korea, Republic of)

    1994-04-15

    The purpose of this paper is to describe the CT findings of a variety of branchial cleft anomalies in the head and neck area. We reviewed the CT findings of 16 patients with neck lesion pathologically proved as branchial cleft anomalies. There were two first and 12 second branchial cleft cysts, one first and one second branchial cleft sinuses. Two cases of first branchial cleft cysts were manifested as thin-walled, cystic masses at auricular area. One first branchial cleft sinus was an external opening type and manifested as an ill-defined, enhancing solid lesion at posterior auricular area. All 12 cases of second branchial cleft cysts demonstrated a typical location, displacing the sternocleidomastoid muscle posteriorly, the carotid artery and internal jugular vein complex medially and the submandibular gland anteriorly. Eight cases of second branchial cleft cysts were seen as fluid-filled, round or ovoid-shaped cysts, and 3 cases of them were seen as irregular-shaped cysts. In one case, suppurative adenopathy with loss of soft tissue planes around the cyst was observed. One case of second branchial cleft sinus was manifested as a tubular-shaped, enhancing lesion at submental area and containing external opening site draining into the anterior border of the sternocleidomastoid muscle. We conclude that CT provides important diagnostic and therapeutic information in patients with a neck mass believed to be a branchial cleft anomaly, as it can differentiate various forms of the branchial anomalies by their characteristic location and shape.

  9. Branchial cleft anomalies: CT evaluation

    International Nuclear Information System (INIS)

    Seok, Eul Hye; Park, Chan Sup

    1994-01-01

    The purpose of this paper is to describe the CT findings of a variety of branchial cleft anomalies in the head and neck area. We reviewed the CT findings of 16 patients with neck lesion pathologically proved as branchial cleft anomalies. There were two first and 12 second branchial cleft cysts, one first and one second branchial cleft sinuses. Two cases of first branchial cleft cysts were manifested as thin-walled, cystic masses at auricular area. One first branchial cleft sinus was an external opening type and manifested as an ill-defined, enhancing solid lesion at posterior auricular area. All 12 cases of second branchial cleft cysts demonstrated a typical location, displacing the sternocleidomastoid muscle posteriorly, the carotid artery and internal jugular vein complex medially and the submandibular gland anteriorly. Eight cases of second branchial cleft cysts were seen as fluid-filled, round or ovoid-shaped cysts, and 3 cases of them were seen as irregular-shaped cysts. In one case, suppurative adenopathy with loss of soft tissue planes around the cyst was observed. One case of second branchial cleft sinus was manifested as a tubular-shaped, enhancing lesion at submental area and containing external opening site draining into the anterior border of the sternocleidomastoid muscle. We conclude that CT provides important diagnostic and therapeutic information in patients with a neck mass believed to be a branchial cleft anomaly, as it can differentiate various forms of the branchial anomalies by their characteristic location and shape

  10. Gaugino-assisted anomaly mediation

    International Nuclear Information System (INIS)

    Kribs, Graham D.

    2001-01-01

    I present a model of supersymmetry breaking mediated through a small extra dimension. Standard model matter multiplets and a supersymmetry-breaking (or 'hidden') sector are confined to opposite four-dimensional boundaries while gauge multiplets live in the bulk. The hidden sector does not contain a singlet and the dominant contribution to gaugino masses is via anomaly-mediated supersymmetry breaking. Scalar masses get contributions from both anomaly mediation and a tiny hard breaking of supersymmetry by operators on the hidden-sector boundary. These operators contribute to scalar masses at one loop and in most of parameter space, their contribution dominates. Thus it is easy to make all squared scalar masses positive. As no additional fields or symmetries are required below the Planck scale, this is among the simplest working models of anomaly mediation. The gaugino spectrum is left untouched and the phenomenology of the model is roughly similar to anomaly mediated supersymmetry breaking with a universal scalar mass added. Finally, the main differences in the spectrum between this model and other approaches are identified. This talk is based on work [1] done in collaboration with David E. Kaplan

  11. Who is afraid of anomalies?

    International Nuclear Information System (INIS)

    Rajaraman, R.

    1990-01-01

    There are situations where gauge symmetry comes into unavoidable conflict with quantum theory. Such situations are examples of what are called 'Anomalies' in quantum field theory. In these cases, although some form of gauge symmetry is present at the classical level, the process of quantisation necessarily destroys that symmetry. How to consistently treat such cases and obtain their novel features is discussed. (author)

  12. Gaugino-Assisted Anomaly Mediation

    International Nuclear Information System (INIS)

    Kaplan, David Elazzar; Kribs, Graham D.

    2000-01-01

    We present a model of supersymmetry breaking mediated through a small extra dimension. Standard model matter multiplets and a supersymmetry-breaking (or ''hidden'') sector are confined to opposite four-dimensional boundaries while gauge multiplets live in the bulk. The hidden sector does not contain a singlet and the dominant contribution to gaugino masses is via anomaly-mediated supersymmetry breaking. Scalar masses get contributions from both anomaly mediation and a tiny hard breaking of supersymmetry by operators on the hidden-sector boundary. These operators contribute to scalar masses at one loop and in most of parameter space, their contribution dominates. Thus it is easy to make all squared scalar masses positive. As no additional fields or symmetries are required below the Planck scale, we consider this the simplest working model of anomaly mediation. The gaugino spectrum is left untouched and the phenomenology of the model is roughly similar to anomaly mediated supersymmetry breaking with a universal scalar mass added. We identify the main differences in the spectrum between this model and other approaches. We also discuss mechanisms for generating the μ term and constraints on additional bulk fields. (author)

  13. Anomaly-specified virtual dimensionality

    Science.gov (United States)

    Chen, Shih-Yu; Paylor, Drew; Chang, Chein-I.

    2013-09-01

    Virtual dimensionality (VD) has received considerable interest where VD is used to estimate the number of spectral distinct signatures, denoted by p. Unfortunately, no specific definition is provided by VD for what a spectrally distinct signature is. As a result, various types of spectral distinct signatures determine different values of VD. There is no one value-fit-all for VD. In order to address this issue this paper presents a new concept, referred to as anomaly-specified VD (AS-VD) which determines the number of anomalies of interest present in the data. Specifically, two types of anomaly detection algorithms are of particular interest, sample covariance matrix K-based anomaly detector developed by Reed and Yu, referred to as K-RXD and sample correlation matrix R-based RXD, referred to as R-RXD. Since K-RXD is only determined by 2nd order statistics compared to R-RXD which is specified by statistics of the first two orders including sample mean as the first order statistics, the values determined by K-RXD and R-RXD will be different. Experiments are conducted in comparison with widely used eigen-based approaches.

  14. Descendants of the Chiral Anomaly

    OpenAIRE

    Jackiw, R.

    2000-01-01

    Chern-Simons terms are well-known descendants of chiral anomalies, when the latter are presented as total derivatives. Here I explain that also Chern-Simons terms, when defined on a 3-manifold, may be expressed as total derivatives.

  15. Anomaly detection in diurnal data

    NARCIS (Netherlands)

    Mata, F.; Zuraniewski, P.W.; Mandjes, M.; Mellia, M.

    2014-01-01

    In this paper we present methodological advances in anomaly detection tailored to discover abnormal traffic patterns under the presence of seasonal trends in data. In our setup we impose specific assumptions on the traffic type and nature; our study features VoIP call counts, for which several

  16. Kohn Anomaly and Phase Stability in Group VB Transition Metals

    Directory of Open Access Journals (Sweden)

    Alexander Landa

    2018-03-01

    Full Text Available In the periodic table, only a few pure metals exhibit lattice or magnetic instabilities associated with Fermi surface nesting, the classical examples being α-U and Cr. Whereas α-U displays a strong Kohn anomaly in the phonon spectrum that ultimately leads to the formation of charge density waves (CDWs, Cr is known for its nesting-induced spin density waves (SDWs. Recently, it has become clear that a pronounced Kohn anomaly and the corresponding softening in the elastic constants is also the key factor that controls structural transformations and mechanical properties in compressed group VB metals—materials with relatively high superconducting critical temperatures. This article reviews the current understanding of the structural and mechanical behavior of these metals under pressure with an introduction to the concept of the Kohn anomaly and how it is related to the important concept of Peierls instability. We review both experimental and theoretical results showing different manifestations of the Kohn anomaly in the transverse acoustic phonon mode TA (ξ00 in V, Nb, and Ta. Specifically, in V the anomaly triggers a structural transition to a rhombohedral phase, whereas in Nb and Ta it leads to an anomalous reduction in yield strength.

  17. The accrual anomaly: Evidence from Borsa Istanbul

    Directory of Open Access Journals (Sweden)

    Nasif Ozkan

    2015-06-01

    Full Text Available In this study, we seek to answer whether stock prices fully reflect information in accruals and cash flows about future earnings. Following prior research, we perform Mishkin test and hedge portfolio analysis. The results based on full sample do not indicate mispricing in the components of earnings on Borsa Istanbul. When we exclude loss firms from the full sample, mispricing of total accruals and its components, and thus the presence of accrual anomaly on Borsa Istanbul, is revealed. Using trading strategy based on total accruals of profit firms, investors may generate abnormal returns of 18.58%. These results may suggest that Borsa Istanbul is not efficient in semi-strong form.

  18. A Generalized Version of a Low Velocity Impact between a Rigid Sphere and a Transversely Isotropic Strain-Hardening Plate Supported by a Rigid Substrate Using the Concept of Noninteger Derivatives

    Directory of Open Access Journals (Sweden)

    Abdon Atangana

    2013-01-01

    Full Text Available A low velocity impact between a rigid sphere and transversely isotropic strain-hardening plate supported by a rigid substrate is generalized to the concept of noninteger derivatives order. A brief history of fractional derivatives order is presented. The fractional derivatives order adopted is in Caputo sense. The new equation is solved via the analytical technique, the Homotopy decomposition method (HDM. The technique is described and the numerical simulations are presented. Since it is very important to accurately predict the contact force and its time history, the three stages of the indentation process, including (1 the elastic indentation, (2 the plastic indentation, and (3 the elastic unloading stages, are investigated.

  19. Focal skin defect, limb anomalies and microphthalmia.

    NARCIS (Netherlands)

    Jackson, K.E.; Andersson, H.C.

    2004-01-01

    We describe two unrelated female patients with congenital single focal skin defects, unilateral microphthalmia and limb anomalies. Growth and psychomotor development were normal and no brain malformation was detected. Although eye and limb anomalies are commonly associated, clinical anophthalmia and

  20. Mesotron Decays and the Role of Anomalies

    OpenAIRE

    Bardeen, William A.

    2007-01-01

    Puzzles associated with Yukawa's mesotron theory of nuclear interactions led to the discovery of "anomalies" in quantum field theory. I will discuss some of the remarkable consequences of these anomalies in the physics of elementary particles.

  1. Needs for reactivity anomaly monitoring in CRBRP

    International Nuclear Information System (INIS)

    Bullock, J.B.

    1975-01-01

    Two general classifications of reactivity anomalies are defined and explicit design criteria and operational philosophy for an anomaly monitoring system for the Clinch River Breeder Reactor are presented. (JWR)

  2. Congenital anomalies of the male urethra

    International Nuclear Information System (INIS)

    Levin, Terry L.; Han, Bokyung; Little, Brent P.

    2007-01-01

    The spectrum of congenital anomalies of the male urethra is presented. The embryologic basis of each anomaly, when known, is discussed. Clinical and imaging features of each entity are presented. (orig.)

  3. Persistence Characteristics of Australian Rainfall Anomalies

    Science.gov (United States)

    Simmonds, Ian; Hope, Pandora

    1997-05-01

    Using 79 years (1913-1991) of Australian monthly precipitation data we examined the nature of the persistence of rainfall anomalies. Analyses were performed for four climate regions covering the country, as well as for the entire Australian continent. We show that rainfall over these regions has high temporal variability and that annual rainfall amounts over all five sectors vary in phase and are, with the exception of the north-west region, significantly correlated with the Southern Oscillation Index (SOI). These relationships were particularly strong during the spring season.It is demonstrated that Australian rainfall exhibits statistically significant persistence on monthly, seasonal, and (to a limited extent) annual time-scales, up to lags of 3 months and one season and 1 year. The persistence showed strong seasonal dependence, with each of the five regions showing memory out to 4 or 5 months from winter and spring. Many aspects of climate in the Australasian region are known to have undergone considerable changes about 1950. We show this to be true for persistence also; its characteristics identified for the entire record were present during the 1951--1980 period, but virtually disappeared in the previous 30-year period.Much of the seasonal distribution of rainfall persistence on monthly time-scales, particularly in the east, is due to the influence of the SOI. However, most of the persistence identified in winter and spring in the north-west is independent of the ENSO phenomenon.Rainfall anomalies following extreme dry and wet months, seasons and years (lowest and highest two deciles) persisted more than would be expected by chance. For monthly extreme events this was more marked in the winter semester for the wet events, except in the south-east region. In general, less persistence was found for the extreme seasons. Although the persistence of dry years was less than would have been expected by chance, the wet years appear to display persistence.

  4. Geophysical Anomalies and Earthquake Prediction

    Science.gov (United States)

    Jackson, D. D.

    2008-12-01

    Finding anomalies is easy. Predicting earthquakes convincingly from such anomalies is far from easy. Why? Why have so many beautiful geophysical abnormalities not led to successful prediction strategies? What is earthquake prediction? By my definition it is convincing information that an earthquake of specified size is temporarily much more likely than usual in a specific region for a specified time interval. We know a lot about normal earthquake behavior, including locations where earthquake rates are higher than elsewhere, with estimable rates and size distributions. We know that earthquakes have power law size distributions over large areas, that they cluster in time and space, and that aftershocks follow with power-law dependence on time. These relationships justify prudent protective measures and scientific investigation. Earthquake prediction would justify exceptional temporary measures well beyond those normal prudent actions. Convincing earthquake prediction would result from methods that have demonstrated many successes with few false alarms. Predicting earthquakes convincingly is difficult for several profound reasons. First, earthquakes start in tiny volumes at inaccessible depth. The power law size dependence means that tiny unobservable ones are frequent almost everywhere and occasionally grow to larger size. Thus prediction of important earthquakes is not about nucleation, but about identifying the conditions for growth. Second, earthquakes are complex. They derive their energy from stress, which is perniciously hard to estimate or model because it is nearly singular at the margins of cracks and faults. Physical properties vary from place to place, so the preparatory processes certainly vary as well. Thus establishing the needed track record for validation is very difficult, especially for large events with immense interval times in any one location. Third, the anomalies are generally complex as well. Electromagnetic anomalies in particular require

  5. Praenatalt diagnosticeret hydronefrose og andre urologiske anomalier

    DEFF Research Database (Denmark)

    Cortes, Dina; Jørgensen, Troels Munch; Rittig, Søren

    2006-01-01

    By renal ultrasound examination, urological anomalies may be demonstrated in 1-2% of fetuses and in about 0.5% of newborns. Boys have about twice the frequency of girls. Surgical treatment is indicated in about one fourth of these urological anomalies. If all pregnant women in Denmark were to hav...... in cases of urological anomalies and guidelines for post-natal diagnosis, follow-up and treatment of these anomalies, especially hydronephrosis....

  6. Airborne detection of magnetic anomalies associated with soils on the Oak Ridge Reservation, Tennessee

    International Nuclear Information System (INIS)

    Doll, W.E.; Beard, L.P.; Helm, J.M.

    1995-01-01

    Reconnaissance airborne geophysical data acquired over the 35,000-acre Oak Ridge Reservation (ORR), TN, show several magnetic anomalies over undisturbed areas mapped as Copper Ridge Dolomite (CRD). The anomalies of interest are most apparent in magnetic gradient maps where they exceed 0.06 nT/m and in some cases exceed 0.5 nT/m. Anomalies as large as 25nT are seen on maps. Some of the anomalies correlate with known or suspected karst, or with apparent conductivity anomalies calculated from electromagnetic data acquired contemporaneously with the magnetic data. Some of the anomalies have a strong correlation with topographic lows or closed depressions. Surface magnetic data have been acquired over some of these sites and have confirmed the existence of the anomalies. Ground inspections in the vicinity of several of the anomalies has not led to any discoveries of manmade surface materials of sufficient size to generate the observed anomalies. One would expect an anomaly of approximately 1 nT for a pickup truck from 200 ft altitude. Typical residual magnetic anomalies have magnitudes of 5--10 nT, and some are as large as 25nT. The absence of roads or other indications of culture (past or present) near the anomalies and the modeling of anomalies in data acquired with surface instruments indicate that man-made metallic objects are unlikely to be responsible for the anomaly. The authors show that observed anomalies in the CRD can reasonably be associated with thickening of the soil layer. The occurrence of the anomalies in areas where evidences of karstification are seen would follow because sediment deposition would occur in topographic lows. Linear groups of anomalies on the maps may be associated with fracture zones which were eroded more than adjacent rocks and were subsequently covered with a thicker blanket of sediment. This study indicates that airborne magnetic data may be of use in other sites where fracture zones or buried collapse structures are of interest

  7. Fetal renal anomalies : diagnosis, management, and outcome

    NARCIS (Netherlands)

    Damen-Elias, Henrica Antonia Maria

    2004-01-01

    In two to three percent of fetuses structural anomalies can be found with prenatal ultrasound investigation. Anomalies of the urinary tract account for 15 to 20% of these anomalies with a detection rate of approximately of 90%. In Chapter 2, 3 and 4 we present reference curves for size and growth

  8. Limb body wall complex: A rare anomaly

    Directory of Open Access Journals (Sweden)

    Panduranga Chikkannaiah

    2013-01-01

    Full Text Available We present autopsy findings of a case of limb body wall complex (LBWC. The fetus had encephalocele, genitourinary agenesis, skeletal anomalies and body wall defects. The rare finding in our case is the occurrence of both cranial and urogenital anomalies. The presence of complex anomalies in this fetus, supports embryonal dysplasia theory of pathogenesis for LBWC.

  9. Anomaly coefficients: Their calculation and congruences

    International Nuclear Information System (INIS)

    Braden, H.W.

    1988-01-01

    A new method for the calculation of anomaly coefficients is presented. For su(n) some explicit and general expressions are given for these. In particular, certain congruences are discovered and investigated among the leading anomaly coefficients. As an application of these congruences, the absence of global six-dimensional gauge anomalies is shown

  10. Holographic entanglement entropy and gravitational anomalies

    NARCIS (Netherlands)

    Castro, A.; Detournay, S.; Iqbal, N.; Perlmutter, E.

    2014-01-01

    We study entanglement entropy in two-dimensional conformal field theories with a gravitational anomaly. In theories with gravity duals, this anomaly is holographically represented by a gravitational Chern-Simons term in the bulk action. We show that the anomaly broadens the Ryu-Takayanagi minimal

  11. The prevalence of congenital anomalies in Europe

    DEFF Research Database (Denmark)

    Dolk, Helen; Loane, Maria; Garne, Ester

    2010-01-01

    EUROCAT (European Surveillance of Congenital Anomalies) is the network of population-based registers of congenital anomaly in Europe, with a common protocol and data quality review, covering 1.5 million annual births in 22 countries. EUROCAT recorded a total prevalence of major congenital anomali...

  12. Effective lagrangian for strong interactions

    International Nuclear Information System (INIS)

    Jain, P.

    1988-01-01

    We attempt to construct a realistic phenomenological Lagrangian in order to describe strong interactions. This is in general a very complicated problem and we shall explore its various aspects. We first include the vector mesons by writing down the most general chiral invariant terms proportional to the Levi-Civita symbol ε μναβ . These terms involve three unknown coefficients, which are calculated by using the experimental results of strong interaction processes. We then calculate the static nucleon properties by finding the solitonic excitations of this model. The results turn out to be, as is also the case for most other vector-pseudoscalar Lagrangians, better than the Skyrme model but are still somewhat different from the experiments. Another aspect that we shall study is the incorporation of scale anomaly of QCD into the Skyrme model. We thus introduce a scalar glueball in our Lagrangian. Here we find an interesting result that the effective glue field dynamically forms a bag for the soliton. Depending on the values of the parameters, we get either a deep bag or a shallow bag. However by including the scalar meson, we find that to get realistic scalar sector we must have the shallow bag. Finally we show some intriguing connections between the chiral quark model, in which the nucleon is described as a solitonic excitation, and the ordinary potential binding quark model

  13. Holomorphic anomaly and quantum mechanics

    Science.gov (United States)

    Codesido, Santiago; Mariño, Marcos

    2018-02-01

    We show that the all-orders WKB periods of one-dimensional quantum mechanical oscillators are governed by the refined holomorphic anomaly equations of topological string theory. We analyze in detail the double-well potential and the cubic and quartic oscillators, and we calculate the WKB expansion of their quantum free energies by using the direct integration of the anomaly equations. We reproduce in this way all known results about the quantum periods of these models, which we express in terms of modular forms on the WKB curve. As an application of our results, we study the large order behavior of the WKB expansion in the case of the double well, which displays the double factorial growth typical of string theory.

  14. Vitellointestinal Duct Anomalies in Infancy

    OpenAIRE

    Kadian, Yogender Singh; Verma, Anjali; Rattan, Kamal Nain; Kajal, Pardeep

    2016-01-01

    Background: Vitellointestinal duct (VID) or omphalomesenteric duct anomalies are secondary to the persistence of the embryonic vitelline duct, which normally obliterates by weeks 5–9 of intrauterine life. Methods: This is a retrospective analysis of a total of 16 patients of symptomatic remnants of vitellointestinal duct from period of Jan 2009 to May 2013. Results: Male to female ratio (M:F) was 4.3:1 and mean age of presentation was 2 months and their mode of presentation was: paten...

  15. Bifid rib: A rare anomaly

    Directory of Open Access Journals (Sweden)

    Mythili Krishnan Rathinasabapathi

    2015-01-01

    Full Text Available A case of the bifid rib was found during routine bone study. The distal part of the osseous rib bifurcated into two divisions with an angle of 60°. Both divisions had their own costal cartilage. Bifid rib is a congenital abnormality of the rib cage and usually asymptomatic, often discovered incidentally on chest X-ray. Effects of this neuroskeletal anomaly can include respiratory difficulties and neurological limitations.

  16. Anomaly mediation in superstring theory

    Energy Technology Data Exchange (ETDEWEB)

    Conlon, Joseph P. [Rudolf Peierls Center for Theoretical Physics, Oxford (United Kingdom); Balliol College, Oxford (United Kingdom); Goodsell, Mark [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Palti, Eran [Centre de Physique Theoretique, Ecole Polytechnique, CNRS, Palaiseau (France)

    2010-08-15

    We study anomaly mediated supersymmetry breaking in type IIB string theory and use our results to test the supergravity formula for anomaly mediated gaugino masses. We compute 1-loop gaugino masses for models of D3-branes on orbifold singularities with 3-form fluxes by calculating the annulus correlator of 3-form flux and two gauginos in the zero momentum limit. Consistent with supergravity expectations we find both anomalous and running contributions to 1-loop gaugino masses. For background Neveu-Schwarz H-flux we find an exact match with the supergravity formula. For Ramond-Ramond flux there is an off-shell ambiguity that precludes a full matching. The anomaly mediated gaugino masses, while determined by the infrared spectrum, arise from an explicit sum over UV open string winding modes. We also calculate brane-to-brane tree-level gravity mediated gaugino masses and show that there are two contributions coming from the dilaton and from the twisted modes, which are suppressed by the full T{sup 6} volume and the untwisted T{sup 2} volume respectively. (orig.)

  17. Anomalies, conformal manifolds, and spheres

    Energy Technology Data Exchange (ETDEWEB)

    Gomis, Jaume [Perimeter Institute for Theoretical Physics,Waterloo, Ontario, N2L 2Y5 (Canada); Hsin, Po-Shen [Department of Physics, Princeton University,Princeton, NJ 08544 (United States); Komargodski, Zohar; Schwimmer, Adam [Weizmann Institute of Science,Rehovot 76100 (Israel); Seiberg, Nathan [School of Natural Sciences, Institute for Advanced Study,Princeton, NJ 08540 (United States); Theisen, Stefan [Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut,14476 Golm (Germany)

    2016-03-04

    The two-point function of exactly marginal operators leads to a universal contribution to the trace anomaly in even dimensions. We study aspects of this trace anomaly, emphasizing its interpretation as a sigma model, whose target space M is the space of conformal field theories (a.k.a. the conformal manifold). When the underlying quantum field theory is supersymmetric, this sigma model has to be appropriately supersymmetrized. As examples, we consider in some detail N=(2,2) and N=(0,2) supersymmetric theories in d=2 and N=2 supersymmetric theories in d=4. This reasoning leads to new information about the conformal manifolds of these theories, for example, we show that the manifold is Kähler-Hodge and we further argue that it has vanishing Kähler class. For N=(2,2) theories in d=2 and N=2 theories in d=4 we also show that the relation between the sphere partition function and the Kähler potential of M follows immediately from the appropriate sigma models that we construct. Along the way we find several examples of potential trace anomalies that obey the Wess-Zumino consistency conditions, but can be ruled out by a more detailed analysis.

  18. Shallow methane hydrate system controls ongoing, downslope sediment transport in a low-velocity active submarine landslide complex, Hikurangi Margin, New Zealand

    Science.gov (United States)

    Mountjoy, Joshu J.; Pecher, Ingo; Henrys, Stuart; Crutchley, Gareth; Barnes, Philip M.; Plaza-Faverola, Andreia

    2014-11-01

    Morphological and seismic data from a submarine landslide complex east of New Zealand indicate flow-like deformation within gas hydrate-bearing sediment. This "creeping" deformation occurs immediately downslope of where the base of gas hydrate stability reaches the seafloor, suggesting involvement of gas hydrates. We present evidence that, contrary to conventional views, gas hydrates can directly destabilize the seafloor. Three mechanisms could explain how the shallow gas hydrate system could control these landslides. (1) Gas hydrate dissociation could result in excess pore pressure within the upper reaches of the landslide. (2) Overpressure below low-permeability gas hydrate-bearing sediments could cause hydrofracturing in the gas hydrate zone valving excess pore pressure into the landslide body. (3) Gas hydrate-bearing sediment could exhibit time-dependent plastic deformation enabling glacial-style deformation. We favor the final hypothesis that the landslides are actually creeping seafloor glaciers. The viability of rheologically controlled deformation of a hydrate sediment mix is supported by recent laboratory observations of time-dependent deformation behavior of gas hydrate-bearing sands. The controlling hydrate is likely to be strongly dependent on formation controls and intersediment hydrate morphology. Our results constitute a paradigm shift for evaluating the effect of gas hydrates on seafloor strength which, given the widespread occurrence of gas hydrates in the submarine environment, may require a reevaluation of slope stability following future climate-forced variation in bottom-water temperature.

  19. A rare anomaly: Double right coronary artery

    Directory of Open Access Journals (Sweden)

    Dursun Çayan Akkoyun

    2013-01-01

    Full Text Available Coronary artery anomalies are rare anomalies. Theseare usually asymptomatic and are discovered incidentally.Double right coronary artery (RCA is a rare coronaryartery anomaly. Although there is controversy aboutidentification and classification of double RCA, it is oftena benign condition, but it can be complicated by atherosclerosisand can lead to serious conditions such asmyocardial infarction (MI and may be accompanied byother anomalies. In our case, double RCA were detectedin coronary angiography for acute anterior MI, and in thenext session successful percutaneous coronary interventionwas performed.Key words: Coronary anomaly, coronary angiography,coronary stenosis

  20. Conjecture on the physical implications of the scale anomaly

    International Nuclear Information System (INIS)

    Hill, Christopher T.; Fermilab

    2005-01-01

    Murray Gell-Mann, after co-inventing QCD, recognized the interplay of the scale anomaly, the renormalization group, and the origin of the strong scale, Λ QCD . I tell a story, then elaborate this concept, and for the sake of discussion, propose a conjecture that the physical world is scale invariant in the classical, ℎ → 0, limit. This principle has implications for the dimensionality of space-time, the cosmological constant, the weak scale, and Planck scale

  1. Algorithms for Anomaly Detection - Lecture 1

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    The concept of statistical anomalies, or outliers, has fascinated experimentalists since the earliest attempts to interpret data. We want to know why some data points don’t seem to belong with the others: perhaps we want to eliminate spurious or unrepresentative data from our model. Or, the anomalies themselves may be what we are interested in: an outlier could represent the symptom of a disease, an attack on a computer network, a scientific discovery, or even an unfaithful partner. We start with some general considerations, such as the relationship between clustering and anomaly detection, the choice between supervised and unsupervised methods, and the difference between global and local anomalies. Then we will survey the most representative anomaly detection algorithms, highlighting what kind of data each approach is best suited to, and discussing their limitations. We will finish with a discussion of the difficulties of anomaly detection in high-dimensional data and some new directions for anomaly detec...

  2. Algorithms for Anomaly Detection - Lecture 2

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    The concept of statistical anomalies, or outliers, has fascinated experimentalists since the earliest attempts to interpret data. We want to know why some data points don’t seem to belong with the others: perhaps we want to eliminate spurious or unrepresentative data from our model. Or, the anomalies themselves may be what we are interested in: an outlier could represent the symptom of a disease, an attack on a computer network, a scientific discovery, or even an unfaithful partner. We start with some general considerations, such as the relationship between clustering and anomaly detection, the choice between supervised and unsupervised methods, and the difference between global and local anomalies. Then we will survey the most representative anomaly detection algorithms, highlighting what kind of data each approach is best suited to, and discussing their limitations. We will finish with a discussion of the difficulties of anomaly detection in high-dimensional data and some new directions for anomaly detec...

  3. 6d, Coulomb branch anomaly matching

    Science.gov (United States)

    Intriligator, Kenneth

    2014-10-01

    6d QFTs are constrained by the analog of 't Hooft anomaly matching: all anomalies for global symmetries and metric backgrounds are constants of RG flows, and for all vacua in moduli spaces. We discuss an anomaly matching mechanism for 6d theories on their Coulomb branch. It is a global symmetry analog of Green-Schwarz-West-Sagnotti anomaly cancellation, and requires the apparent anomaly mismatch to be a perfect square, . Then Δ I 8 is cancelled by making X 4 an electric/magnetic source for the tensor multiplet, so background gauge field instantons yield charged strings. This requires the coefficients in X 4 to be integrally quantized. We illustrate this for theories. We also consider the SCFTs from N small E8 instantons, verifying that the recent result for its anomaly polynomial fits with the anomaly matching mechanism.

  4. Coronary anomalies: what the radiologist should know*

    Science.gov (United States)

    Neves, Priscilla Ornellas; Andrade, Joalbo; Monção, Henry

    2015-01-01

    Coronary anomalies comprise a diverse group of malformations, some of them asymptomatic with a benign course, and the others related to symptoms as chest pain and sudden death. Such anomalies may be classified as follows: 1) anomalies of origination and course; 2) anomalies of intrinsic coronary arterial anatomy; 3) anomalies of coronary termination. The origin and the proximal course of anomalous coronary arteries are the main prognostic factors, and interarterial course or a coronary artery is considered to be malignant due its association with increased risk of sudden death. Coronary computed tomography angiography has become the reference method for such an assessment as it detects not only anomalies in origination of these arteries, but also its course in relation to other mediastinal structures, which plays a relevant role in the definition of the therapeutic management. Finally, it is essential for radiologists to recognize and characterize such anomalies. PMID:26379322

  5. Testing strong interaction theories

    International Nuclear Information System (INIS)

    Ellis, J.

    1979-01-01

    The author discusses possible tests of the current theories of the strong interaction, in particular, quantum chromodynamics. High energy e + e - interactions should provide an excellent means of studying the strong force. (W.D.L.)

  6. Altered orientation and flight paths of pigeons reared on gravity anomalies: a GPS tracking study.

    Directory of Open Access Journals (Sweden)

    Nicole Blaser

    Full Text Available The mechanisms of pigeon homing are still not understood, in particular how they determine their position at unfamiliar locations. The "gravity vector" theory holds that pigeons memorize the gravity vector at their home loft and deduct home direction and distance from the angular difference between memorized and actual gravity vector. However, the gravity vector is tilted by different densities in the earth crust leading to gravity anomalies. We predicted that pigeons reared on different gravity anomalies would show different initial orientation and also show changes in their flight path when crossing a gravity anomaly. We reared one group of pigeons in a strong gravity anomaly with a north-to-south gravity gradient, and the other group of pigeons in a normal area but on a spot with a strong local anomaly with a west-to-east gravity gradient. After training over shorter distances, pigeons were released from a gravitationally and geomagnetically normal site 50 km north in the same direction for both home lofts. As expected by the theory, the two groups of pigeons showed divergent initial orientation. In addition, some of the GPS-tracked pigeons also showed changes in their flight paths when crossing gravity anomalies. We conclude that even small local gravity anomalies at the birth place of pigeons may have the potential to bias the map sense of pigeons, while reactivity to gravity gradients during flight was variable and appeared to depend on individual navigational strategies and frequency of position updates.

  7. Congenital anomalies in Primorsky region.

    Science.gov (United States)

    Kiku, P; Voronin, S; Golokhvast, K

    2015-01-01

    According to WHO hereditary diseases and congenital malformations contribute significantly to the health of population. Thus, the problems of epidemiology, clinical presentation, diagnosis and treatment of congenital abnormalities are of interest for many researchers [2]. In addition, the dynamic accounting for the incidence of congenital malformations and hereditary diseases allows the researchers to assess the ecological situation in the region [1]. The occurrence of congenital anomalies in the world varies; it depends heavily on how carefully the data is collected [4]. Multifactorial or polygenic diseases develop under the influence of environmental factors in the presence of defective genes. They can constitute up to 90% of all chronic pathology [2-5]. To determine the incidence of congenital anomalies under the influence of environmental factors. The study used the methodology of system evaluation of congenital anomalies incidence in Primorsky region, depending on bio-climatic and environmental conditions. The authors used health statistics for the period from 2000 to 2014, F.12 class for congenital abnormalities in adolescents and children that were compared in geographical and temporal aspects with environmental factors of 33 settlements in Primorsky region. The environment is represented by nature and climate (6 factor modules) and sanitation (7 factor modules) blocks of factors. When formalizing the information database of the environment a specially developed 10-point assessment scale was used. Statistical processing of the information was carried out using Pearson's chi-squared test and multiple regression method from SSPS application program package. The study found that over the 15-year period the level of congenital abnormalities in children increased by 27.5% and in adolescents - by 35.1%, and in 2014 it amounted to 1687.6 and 839.3 per 100 000 people, respectively. The predictive model shows a steady further growth of this pathology. The incidence

  8. Prenatal sonographic diagnosis of focal musculoskeletal anomalies

    International Nuclear Information System (INIS)

    Ryu, Jung-Kyu; Cho, Jeong-Yeon; Choi, Jong-Sun

    2003-01-01

    Focal musculoskeletal anomalies vary, and can manifest as part of a syndrome or be accompanied by numerous other conditions such as genetic disorders, karyotype abnormalities, central nervous system anomalies and other skeletal anomalies, lsolated focal musculoskeletal anomaly does, however, also occur; its early prenatal diagnosis is important in deciding prenatal care, and also helps in counseling parents about the postnatal effects of numerous possible associated anomalies. We have encountered 50 cases involving focal musculoskeletal anomalies, including total limb dysplasia [radial ray abnormality (n=3), mesomelic dysplasia (n=1)]; anomalies of the hand [polydactyly (n=8), syndactyly (n=3), ectrodactyly (n=1), clinodactyly (n=6), clenched hand (n=5)]; anomalies of the foot [clubfoot (n=10), rockerbottom foot (n=5), sandal gap deformity (n=1), curly toe (n=2)]; amniotic band syndrome (n=3); and anomalies of the focal spine [block vertebra (n=1), hemivertebra (n=1)]. Among these 50 cases, five [polydactyly (n=1), syndactyly (n=2) and curly toe (n=2) were confirmed by postnatal physical evaluation, two (focal spine anomalies) were diagnosed after postnatal radiologic examination, and the remaining 43 were proven at autopsy. For each condition, we describe the prenatal sonographic findings, and include a brief review

  9. Prenatal sonographic diagnosis of focal musculoskeletal anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jung-Kyu; Cho, Jeong-Yeon; Choi, Jong-Sun [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2003-12-15

    Focal musculoskeletal anomalies vary, and can manifest as part of a syndrome or be accompanied by numerous other conditions such as genetic disorders, karyotype abnormalities, central nervous system anomalies and other skeletal anomalies, lsolated focal musculoskeletal anomaly does, however, also occur; its early prenatal diagnosis is important in deciding prenatal care, and also helps in counseling parents about the postnatal effects of numerous possible associated anomalies. We have encountered 50 cases involving focal musculoskeletal anomalies, including total limb dysplasia [radial ray abnormality (n=3), mesomelic dysplasia (n=1)]; anomalies of the hand [polydactyly (n=8), syndactyly (n=3), ectrodactyly (n=1), clinodactyly (n=6), clenched hand (n=5)]; anomalies of the foot [clubfoot (n=10), rockerbottom foot (n=5), sandal gap deformity (n=1), curly toe (n=2)]; amniotic band syndrome (n=3); and anomalies of the focal spine [block vertebra (n=1), hemivertebra (n=1)]. Among these 50 cases, five [polydactyly (n=1), syndactyly (n=2) and curly toe (n=2) were confirmed by postnatal physical evaluation, two (focal spine anomalies) were diagnosed after postnatal radiologic examination, and the remaining 43 were proven at autopsy. For each condition, we describe the prenatal sonographic findings, and include a brief review.

  10. Strongly interacting matter in magnetic fields

    CERN Document Server

    Landsteiner, Karl; Schmitt, Andreas; Yee, Ho-Ung

    2013-01-01

    The physics of strongly interacting matter in an external magnetic field is presently emerging as a topic of great cross-disciplinary interest for particle, nuclear, astro- and condensed matter physicists. It is known that strong magnetic fields are created in heavy ion collisions, an insight that has made it possible to study a variety of surprising and intriguing phenomena that emerge from the interplay of quantum anomalies, the topology of non-Abelian gauge fields, and the magnetic field. In particular, the non-trivial topological configurations of the gluon field induce a non-dissipative electric current in the presence of a magnetic field. These phenomena have led to an extended formulation of relativistic hydrodynamics, called chiral magnetohydrodynamics. Hitherto unexpected applications in condensed matter physics include graphene and topological insulators. Other fields of application include astrophysics, where strong magnetic fields exist in magnetars and pulsars. Last but not least, an important ne...

  11. Power coefficient anomaly in JOYO

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, H

    1980-12-15

    Operation of the JOYO experimental fast reactor with the MK-I core has been divided into two phases: (1) 50 MWt power ascension and operation; and (2) 75 MWt power ascension and operation. The 50 MWt power-up tests were conducted in August 1978. In these tests, the measured reactivity loss due to power increases from 15 MWt to 50 MWt was 0.28% ..delta.. K/K, and agreed well with the predicted value of 0.27% ..delta.. K/K. The 75 MWt power ascension tests were conducted in July-August 1979. In the process of the first power increase above 50 MWt to 65 MWt conducted on July 11, 1979, an anomalously large negative power coefficient was observed. The value was about twice the power coefficient values measured in the tests below 50 MW. In order to reproduce the anomaly, the reactor power was decreased and again increased up to the maximum power of 65 MWt. However, the large negative power coefficient was not observed at this time. In the succeeding power increase from 65 MWt to 75 MWt, a similar anomalous power coefficient was again observed. This anomaly disappeared in the subsequent power ascensions to 75 MWt, and the magnitude of the power coefficient gradually decreased with power cycles above the 50 MWt level.

  12. Titanium isotopic anomalies in meteorites

    International Nuclear Information System (INIS)

    Niemeyer, S.; Lugmair, G.W.

    1984-01-01

    High-precision analyses of Ti are reported for samples from a variety of meteorite classes. The expanded data base for Allende inclusions still shows Ti isotope anomalies in every inclusion. All the coarse-grained inclusions give quite similar patterns, but fine-grained inclusions show more variable, and sometimes larger, anomalies. One inclusion, 3675A, was analyzed because others identified it as a possible 'FUN' inclusion due to its mass-fractionated Mg. This designation is supported by the significantly more complex Ti isotopic pattern for 3675A compared to all our other Allende inclusions. Available data fail to suggest that any particular Allende mineral phase, including a chromite-carbon fraction from an acid residue, is especially rich in anomalous Ti. We also find anomalous Ti in a bulk sample of a C1 chondrite and in matrix separates from C2 chondrites. The excesses of 50 Ti are smaller than for Allende inclusions, and subtle differences in Ti isotopic patterns tentatively suggest that parent materials for C1-C2 matrix and Allende inclusions are not directly related. Analyses of chondrules from unequilibrated ordinary chondrites did not yield clear evidence for anomalous Ti, but some 'larger than usual' deficits at 50/46 give encouragement for future work in this direction. (author)

  13. Corpuscular radiation and congenital anomalies

    International Nuclear Information System (INIS)

    Sato, Shinji; Yajima, Akira

    1983-01-01

    Many explorations have been done by our antecessors to find out about the congenital anomalies which might be caused by X-ray or γ-ray and experimental teratological researches have also been done, with some results. However, there have been less systematic studies on corpuscular radiation. Neutron ray is a radioactive ray no electrically-charged equally as photon (X-ray, γ-ray). With an equal dosage of it as photon's, its localized energy is high so that it is different in RBE, OER, etc. In heavy charged particle (proton ray, He ion, Ne ion, π-meson ray), there is the characteristic that the energy increases at around the deepest spot within the range rather than at the point of injection into a system, which is called Bragg peak. The type and energy of this radiation reflected in the uniqueness in energy distribution, in ionization density and in LET makes it the most important radioactive biological parameter. At this paper, we shall review the types of radioactive rays and discuss the congenital anomalies (teratogenecity) including the experimental results obtained by application of our proton ray. (author)

  14. Axial anomalies of Lifshitz fermions

    CERN Document Server

    Bakas, Ioannis

    2011-01-01

    We compute the axial anomaly of a Lifshitz fermion theory with anisotropic scaling z=3 which is minimally coupled to geometry in 3+1 space-time dimensions. We find that the result is identical to the relativistic case using path integral methods. An independent verification is provided by showing with spectral methods that the eta-invariant of the Dirac and Lifshitz fermion operators in three dimensions are equal. Thus, by the integrated form of the anomaly, the index of the Dirac operator still accounts for the possible breakdown of chiral symmetry in non-relativistic theories of gravity. We apply this framework to the recently constructed gravitational instanton backgrounds of Horava-Lifshitz theory and find that the index is non-zero provided that the space-time foliation admits leaves with harmonic spinors. Using Hitchin's construction of harmonic spinors on Berger spheres, we obtain explicit results for the index of the fermion operator on all such gravitational instanton backgrounds with SU(2)xU(1) isom...

  15. A study of dental anomalies

    International Nuclear Information System (INIS)

    Yang, Sook; Kim, Jae Duck

    1993-01-01

    The purpose of this study was to find out the prevalence of dental anomalies in 600 normal persons (male:363, female:237) at age 14 to 39 years, through history taking, oral examination, and radiographic observations of subjects. The obtained results were as follows: 1. The prevalence of individual dental anomalies were as follows; Congenitally missing teeth 7%; supernumerary teeth 1.33%; ectopic eruption 8.50%; transposition 0.33%; rotation 23.67%; microdontia 11.16% (peg lateral is 5.33%; third molar 5.83%); prolonged retention of deciduous teeth 1.33%; crowding 49.83%; and spacing 15.17%. 2. Alterations in numbers of teeth : The most frequently missing teeth were mandibular lateral incisors, followed by mandibular second premolars and maxillary second premolars. In numbers of congenitally missing teeth per person, 52.38% had one missing tooth and 30.95% had two missing teeth. In supernumerary teeth, there was higher rate in male than in female. Most supernumerary teeth were mesiodens of median area in maxilla and the eruption pattern of that teeth generally was unerupted state. 3. In transposition, exchange of position of teeth involved the canine and first premolar. 4. Congenital missing rate of permanent successors in prolonged retention of deciduous teeth was 69.23%. 5. Crowding and spacing had respectively higher rate in mandible and in maxilla.

  16. Global anomalies in chiral lattice gauge theories

    International Nuclear Information System (INIS)

    Baer, O.

    2000-07-01

    We study global anomalies in a new approach to chiral gauge theories on the lattice, which is based on the Ginsparg-Wilson relation. In this approach, global anomalies make it impossible to define consistently a fermionic measure for the functional integral. We show that a global anomaly occurs in an SU(2) theory if the fundamental representation is used for the fermion fields. The generalization to higher representations is also discussed. In addition we establish a close relation between global anomalies and the spectral flow of the Dirac operator and employ it in a numerical computation to prove the existence of the global SU(2) anomaly in a different way. This method is inspired by an earlier work of Witten who first discovered this type of anomalies in continuum field theory. (orig.)

  17. Renal anomalies in congenital heart disease

    International Nuclear Information System (INIS)

    Lee, Byung Hee; Kim, In One; Yeon, Kyung Mo; Yoon, Yong Soo

    1987-01-01

    In general, the incidence of urinary tract anomalies in congenital heart disease is higher than that in general population. So authors performed abdominal cineradiography in 1045 infants and children undergoing cineangiographic examinations for congenital heart disease, as a screening method for the detection, the incidence, and the nature of associated urinary tract anomalies. The results were as follows: 1. The incidence of urinary tract anomaly associated with congenital heart disease was 4.1% (<2% in general population). 2. Incidence of urinary tract anomalies was 4.62% in 671 acyanotic heart diseases, 3.20% in 374 cyanotic heart diseases. 3. There was no constant relationship between the type of cardiac anomaly and the type of urinary tract anomaly

  18. On Newton-Cartan trace anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Auzzi, Roberto [Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore,Via Musei 41, 25121 Brescia (Italy); INFN Sezione di Perugia,Via A. Pascoli, 06123 Perugia (Italy); Baiguera, Stefano [Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore,Via Musei 41, 25121 Brescia (Italy); Nardelli, Giuseppe [Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore,Via Musei 41, 25121 Brescia (Italy); TIFPA - INFN, c/o Dipartimento di Fisica, Università di Trento,38123 Povo (Italy)

    2016-02-01

    We classify the trace anomaly for parity-invariant non-relativistic Schrödinger theories in 2+1 dimensions coupled to background Newton-Cartan gravity. The general anomaly structure looks very different from the one in the z=2 Lifshitz theories. The type A content of the anomaly is remarkably identical to that of the relativistic 3+1 dimensional case, suggesting the conjecture that an a-theorem should exist also in the Newton-Cartan context.

  19. Anomalies and modular invariance in string theory

    International Nuclear Information System (INIS)

    Schellekens, A.N.; Warner, N.P.

    1986-01-01

    All known anomaly cancellations of heterotic string theories are derived directly from one-loop modular invariance, and are shown to be related to a property of modular functions of weight 2. Using modular invariance infinite classes of anomaly free field theories are constructed in (8m+2) dimensions for any m. A generating function is obtained for the anomalies of string-related field theories in (8m+2) dimensions. (orig.)

  20. On Newton-Cartan trace anomalies

    International Nuclear Information System (INIS)

    Auzzi, Roberto; Baiguera, Stefano; Nardelli, Giuseppe

    2016-01-01

    We classify the trace anomaly for parity-invariant non-relativistic Schrödinger theories in 2+1 dimensions coupled to background Newton-Cartan gravity. The general anomaly structure looks very different from the one in the z=2 Lifshitz theories. The type A content of the anomaly is remarkably identical to that of the relativistic 3+1 dimensional case, suggesting the conjecture that an a-theorem should exist also in the Newton-Cartan context.

  1. Higher derivative regularization and chiral anomaly

    International Nuclear Information System (INIS)

    Nagahama, Yoshinori.

    1985-02-01

    A higher derivative regularization which automatically leads to the consistent chiral anomaly is analyzed in detail. It explicitly breaks all the local gauge symmetry but preserves global chiral symmetry and leads to the chirally symmetric consistent anomaly. This regularization thus clarifies the physics content contained in the consistent anomaly. We also briefly comment on the application of this higher derivative regularization to massless QED. (author)

  2. Network anomaly detection a machine learning perspective

    CERN Document Server

    Bhattacharyya, Dhruba Kumar

    2013-01-01

    With the rapid rise in the ubiquity and sophistication of Internet technology and the accompanying growth in the number of network attacks, network intrusion detection has become increasingly important. Anomaly-based network intrusion detection refers to finding exceptional or nonconforming patterns in network traffic data compared to normal behavior. Finding these anomalies has extensive applications in areas such as cyber security, credit card and insurance fraud detection, and military surveillance for enemy activities. Network Anomaly Detection: A Machine Learning Perspective presents mach

  3. Insights on the cuprate high energy anomaly observed in ARPES

    International Nuclear Information System (INIS)

    Moritz, B.; Johnston, S.; Devereaux, T.P.

    2010-01-01

    Recently, angle-resolved photoemission spectroscopy has been used to highlight an anomalously large band renormalization at high binding energies in cuprate superconductors: the high energy 'waterfall' or high energy anomaly (HEA). The anomaly is present for both hole- and electron-doped cuprates as well as the half-filled parent insulators with different energy scales arising on either side of the phase diagram. While photoemission matrix elements clearly play a role in changing the aesthetic appearance of the band dispersion, i.e. creating a 'waterfall'-like appearance, they provide an inadequate description for the physics that underlies the strong band renormalization giving rise to the HEA. Model calculations of the single-band Hubbard Hamiltonian showcase the role played by correlations in the formation of the HEA and uncover significant differences in the HEA energy scale for hole- and electron-doped cuprates. In addition, this approach properly captures the transfer of spectral weight accompanying doping in a correlated material and provides a unifying description of the HEA across both sides of the cuprate phase diagram. We find that the anomaly demarcates a transition, or cross-over, from a quasiparticle band at low binding energies near the Fermi level to valence bands at higher binding energy, assumed to be of strong oxygen character.

  4. Insights on the cuprate high energy anomaly observed in ARPES

    Energy Technology Data Exchange (ETDEWEB)

    Moritz, B., E-mail: moritzb@slac.stanford.ed [Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Department of Physics and Astrophysics, University of North Dakota, Grand Forks, ND 58202 (United States); Johnston, S. [Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Department of Physics and Astronomy, University of Waterloo, Waterloo, ON N2L 3G1 (Canada); Devereaux, T.P. [Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305 (United States)

    2010-07-15

    Recently, angle-resolved photoemission spectroscopy has been used to highlight an anomalously large band renormalization at high binding energies in cuprate superconductors: the high energy 'waterfall' or high energy anomaly (HEA). The anomaly is present for both hole- and electron-doped cuprates as well as the half-filled parent insulators with different energy scales arising on either side of the phase diagram. While photoemission matrix elements clearly play a role in changing the aesthetic appearance of the band dispersion, i.e. creating a 'waterfall'-like appearance, they provide an inadequate description for the physics that underlies the strong band renormalization giving rise to the HEA. Model calculations of the single-band Hubbard Hamiltonian showcase the role played by correlations in the formation of the HEA and uncover significant differences in the HEA energy scale for hole- and electron-doped cuprates. In addition, this approach properly captures the transfer of spectral weight accompanying doping in a correlated material and provides a unifying description of the HEA across both sides of the cuprate phase diagram. We find that the anomaly demarcates a transition, or cross-over, from a quasiparticle band at low binding energies near the Fermi level to valence bands at higher binding energy, assumed to be of strong oxygen character.

  5. Major congenital anomalies in a Danish region

    DEFF Research Database (Denmark)

    Garne, Ester; Hansen, Anne Vinkel; Birkelund, Anne Sofie

    2014-01-01

    INTRODUCTION: This study describes the prevalence of congenital anomalies and changes over time in birth outcome, mortality and chronic maternal diseases. MATERIAL AND METHODS: This study was based on population data from the EUROCAT registry covering the Funen County, Denmark, 1995...... mortality decreased significantly over time for cases with major congenital anomalies (p congenital anomaly cases, 8% had a registration of one of these chronic maternal diseases......: diabetes, epilepsy, mental disorder, thyroid disease, asthma, or inflammatory bowel disease. Medication for these conditions accounted for 46% of maternal drug use. CONCLUSION: Maternal morbidity and use of potentially teratogenic medication have increased among congenital anomaly cases. Foetal and infant...

  6. Spreading rate dependence of gravity anomalies along oceanic transform faults.

    Science.gov (United States)

    Gregg, Patricia M; Lin, Jian; Behn, Mark D; Montési, Laurent G J

    2007-07-12

    Mid-ocean ridge morphology and crustal accretion are known to depend on the spreading rate of the ridge. Slow-spreading mid-ocean-ridge segments exhibit significant crustal thinning towards transform and non-transform offsets, which is thought to arise from a three-dimensional process of buoyant mantle upwelling and melt migration focused beneath the centres of ridge segments. In contrast, fast-spreading mid-ocean ridges are characterized by smaller, segment-scale variations in crustal thickness, which reflect more uniform mantle upwelling beneath the ridge axis. Here we present a systematic study of the residual mantle Bouguer gravity anomaly of 19 oceanic transform faults that reveals a strong correlation between gravity signature and spreading rate. Previous studies have shown that slow-slipping transform faults are marked by more positive gravity anomalies than their adjacent ridge segments, but our analysis reveals that intermediate and fast-slipping transform faults exhibit more negative gravity anomalies than their adjacent ridge segments. This finding indicates that there is a mass deficit at intermediate- and fast-slipping transform faults, which could reflect increased rock porosity, serpentinization of mantle peridotite, and/or crustal thickening. The most negative anomalies correspond to topographic highs flanking the transform faults, rather than to transform troughs (where deformation is probably focused and porosity and alteration are expected to be greatest), indicating that crustal thickening could be an important contributor to the negative gravity anomalies observed. This finding in turn suggests that three-dimensional magma accretion may occur near intermediate- and fast-slipping transform faults.

  7. Abortion: Strong's counterexamples fail

    DEFF Research Database (Denmark)

    Di Nucci, Ezio

    2009-01-01

    This paper shows that the counterexamples proposed by Strong in 2008 in the Journal of Medical Ethics to Marquis's argument against abortion fail. Strong's basic idea is that there are cases--for example, terminally ill patients--where killing an adult human being is prima facie seriously morally...

  8. Strong Langmuir turbulence

    International Nuclear Information System (INIS)

    Goldman, M.V.

    1984-01-01

    After a brief discussion of beam-excited Langmuir turbulence in the solar wind, we explain the criteria for wave-particle, three-wave and strong turbulence interactions. We then present the results of a numerical integration of the Zakharov equations, which describe the strong turbulence saturation of a weak (low-density) high energy, bump-on-tail beam instability. (author)

  9. Paleomagnetic evidence for the persistence or recurrence of the South Atlantic geomagnetic Anomaly

    Science.gov (United States)

    Shah, Jay; Koppers, Anthony A. P.; Leitner, Marko; Leonhardt, Roman; Muxworthy, Adrian R.; Heunemann, Christoph; Bachtadse, Valerian; Ashley, Jack A. D.; Matzka, Jürgen

    2017-04-01

    The South Atlantic geomagnetic Anomaly (SAA) is known as a region of the geomagnetic field that is approximately 25 μT in intensity, compared to an expected value of ˜43 μT. Geomagnetic field models do not find evidence for the SAA being a persistent feature of the geomagnetic field, however these models are constructed from paleomagnetic data that is sparse in the southern hemisphere. We present a full-vector paleomagnetic study of 40Ar/39Ar dated Late Pleistocene lavas from Tristan da Cunha in the South Atlantic Ocean (Shah et al., 2016; EPSL). Paleointensity estimations using the Thellier method of eight lava flows yield an average paleointensity of the Tristan da Cunha lavas as 18 ± 6 μT and an average virtual axial dipole moment (VADM) of 3.1 ± 1.2 × 1022 Am2. Comparing the VADM of the lava flows against the PADM2M, PINT and SINT-800 databases indicates that the lava flows represent four distinct periods of anomalously weak intensity in the South Atlantic between 43 and 90 ka ago, constrained by newly obtained 40Ar/39Ar ages. This anomalously weak intensity in the Late Pleistocene is similar to the present-day SAA and SAA-like anomalous behavior found in the recent archeomagnetic study by Tarduno et al. (2015; Nat. Commun.). Our dataset provides evidence for the persistence or recurrence of geomagnetic main field anomalies in the South Atlantic, and potentially indicates such anomalies are the geomagnetic field manifestation of the long-existing core-mantle boundary heterogeneity seismically identified as the African Large Low Velocity Shear Province (LLSVP).

  10. [Double second branchial cleft anomaly].

    Science.gov (United States)

    Muñoz-Fernández, Noelia; Mallea-Cañizares, Ismael; Fernández-Julián, Enrique; De La Fuente-Arjona, Luís; Marco-Algarra, Jaime

    2011-01-01

    Second branchial cleft anomalies are the most common of this type of neck masses. They can be classified in four types (Bailey/Proctor classification) according to their location. Type II is the most common, and related to vital neck structures such as the carotid artery and jugular vein. Cysts are the most frequent among them. Management consists of surgical excision of the cyst and tract by cervicotomy to avoid recurrence. We present an extremely rare case of a 32-year-old male who presented a sudden appearance of a right lateral neck mass that was identified by an image study as a double branchial cleft cyst. A review of simultaneous branchial cleft cyst in the literature is also made. Copyright © 2009 Elsevier España, S.L. All rights reserved.

  11. Vitellointestinal Duct Anomalies in Infancy.

    Science.gov (United States)

    Kadian, Yogender Singh; Verma, Anjali; Rattan, Kamal Nain; Kajal, Pardeep

    2016-01-01

    Vitellointestinal duct (VID) or omphalomesenteric duct anomalies are secondary to the persistence of the embryonic vitelline duct, which normally obliterates by weeks 5-9 of intrauterine life. This is a retrospective analysis of a total of 16 patients of symptomatic remnants of vitellointestinal duct from period of Jan 2009 to May 2013. Male to female ratio (M:F) was 4.3:1 and mean age of presentation was 2 months and their mode of presentation was: patent VID in 9 (56.25%) patients, umbilical cyst in 2(12.25%), umbilical granuloma in 2 (12.25%), and Meckel diverticulum as content of hernia sac in obstructed umbilical hernia in 1 (6.25%) patient. Two patients with umbilical fistula had severe electrolyte disturbance and died without surgical intervention. Persistent VID may have varied presentations in infancy. High output umbilical fistula and excessive bowel prolapse demand urgent surgical intervention to avoid morbidity and mortality.

  12. GRAVITY ANOMALIES OF THE MOON

    Directory of Open Access Journals (Sweden)

    S. G. Pugacheva

    2015-01-01

    Full Text Available The source of gravity anomalies of the Moon are large mascons with a high mass concentration at a depth of volcanic plains and lunar Maria. New data on the gravitational field of the Moon were obtained from two Grail spacecrafts. The article presents the data of physical and mechanical properties of the surface soil layer of the lunar Maria and gives an assessment of the chemical composition of the soil. There have been calculated heterogeneity parameters of the surface macro-relief of the lunar Maria: albedo, soil density, average grain diameter of the particles forming the surface layer and the volume fraction occupied by particles. It can be assumed that mascons include rich KREEP rocks with a high content of thorium and iron oxide. Formation of mascons is connected with intensive development of basaltic volcanism on the Moon in the early periods of its existence.

  13. THE CORONAL ABUNDANCE ANOMALIES OF M DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Brian E.; Laming, J. Martin [Naval Research Laboratory, Space Science Division, Washington, DC 20375 (United States); Karovska, Margarita, E-mail: brian.wood@nrl.navy.mil [Smithsonian Astrophysical Observatory, 60 Garden St., Cambridge, MA 02138 (United States)

    2012-07-01

    We analyze Chandra X-ray spectra of the M0 V+M0 V binary GJ 338. As quantified by X-ray surface flux, these are the most inactive M dwarfs ever observed with X-ray grating spectroscopy. We focus on measuring coronal abundances, in particular searching for evidence of abundance anomalies related to first ionization potential (FIP). In the solar corona and wind, low-FIP elements are overabundant, which is the so-called FIP effect. For other stars, particularly very active ones, an 'inverse FIP effect' is often observed, with low-FIP elements being underabundant. For both members of the GJ 338 binary, we find evidence for a modest inverse FIP effect, consistent with expectations from a previously reported correlation between spectral type and FIP bias. This amounts to strong evidence that all M dwarfs should exhibit the inverse FIP effect phenomenon, not just the active ones. We take the first step toward modeling the inverse FIP phenomenon in M dwarfs, building on past work that has demonstrated that MHD waves coursing through coronal loops can lead to a ponderomotive force that fractionates elements in a manner consistent with the FIP effect. We demonstrate that in certain circumstances this model can also lead to an inverse FIP effect, pointing the way to more detailed modeling of M dwarf coronal abundances in the future.

  14. The Coronal Abundance Anomalies of M Dwarfs

    Science.gov (United States)

    Wood, Brian E.; Laming, J. Martin; Karovska, Margarita

    2012-07-01

    We analyze Chandra X-ray spectra of the M0 V+M0 V binary GJ 338. As quantified by X-ray surface flux, these are the most inactive M dwarfs ever observed with X-ray grating spectroscopy. We focus on measuring coronal abundances, in particular searching for evidence of abundance anomalies related to first ionization potential (FIP). In the solar corona and wind, low-FIP elements are overabundant, which is the so-called FIP effect. For other stars, particularly very active ones, an "inverse FIP effect" is often observed, with low-FIP elements being underabundant. For both members of the GJ 338 binary, we find evidence for a modest inverse FIP effect, consistent with expectations from a previously reported correlation between spectral type and FIP bias. This amounts to strong evidence that all M dwarfs should exhibit the inverse FIP effect phenomenon, not just the active ones. We take the first step toward modeling the inverse FIP phenomenon in M dwarfs, building on past work that has demonstrated that MHD waves coursing through coronal loops can lead to a ponderomotive force that fractionates elements in a manner consistent with the FIP effect. We demonstrate that in certain circumstances this model can also lead to an inverse FIP effect, pointing the way to more detailed modeling of M dwarf coronal abundances in the future.

  15. THE CORONAL ABUNDANCE ANOMALIES OF M DWARFS

    International Nuclear Information System (INIS)

    Wood, Brian E.; Laming, J. Martin; Karovska, Margarita

    2012-01-01

    We analyze Chandra X-ray spectra of the M0 V+M0 V binary GJ 338. As quantified by X-ray surface flux, these are the most inactive M dwarfs ever observed with X-ray grating spectroscopy. We focus on measuring coronal abundances, in particular searching for evidence of abundance anomalies related to first ionization potential (FIP). In the solar corona and wind, low-FIP elements are overabundant, which is the so-called FIP effect. For other stars, particularly very active ones, an 'inverse FIP effect' is often observed, with low-FIP elements being underabundant. For both members of the GJ 338 binary, we find evidence for a modest inverse FIP effect, consistent with expectations from a previously reported correlation between spectral type and FIP bias. This amounts to strong evidence that all M dwarfs should exhibit the inverse FIP effect phenomenon, not just the active ones. We take the first step toward modeling the inverse FIP phenomenon in M dwarfs, building on past work that has demonstrated that MHD waves coursing through coronal loops can lead to a ponderomotive force that fractionates elements in a manner consistent with the FIP effect. We demonstrate that in certain circumstances this model can also lead to an inverse FIP effect, pointing the way to more detailed modeling of M dwarf coronal abundances in the future.

  16. Cryosphere: a kingdom of anomalies and diversity

    Science.gov (United States)

    Melnikov, Vladimir; Gennadinik, Viktor; Kulmala, Markku; Lappalainen, Hanna K.; Petäjä, Tuukka; Zilitinkevich, Sergej

    2018-05-01

    The cryosphere of the Earth overlaps with the atmosphere, hydrosphere and lithosphere over vast areas with temperatures below 0 °C and pronounced H2O phase changes. In spite of its strong variability in space and time, the cryosphere plays the role of a global thermostat, keeping the thermal regime on the Earth within rather narrow limits, affording continuation of the conditions needed for the maintenance of life. Objects and processes related to cryosphere are very diverse, due to the following basic reasons: the anomalous thermodynamic and electromagnetic properties of H2O, the intermediate intensity of hydrogen bonds and the wide spread of cryogenic systems all over the Earth. However, these features attract insufficient attention from research communities. Cryology is usually understood as a descriptive discipline within physical geography, limited to glaciology and permafrost research. We emphasise its broad interdisciplinary landscape involving physical, chemical and biological phenomena related to the H2O phase transitions and various forms of ice. This paper aims to draw the attention of readers to the crucial importance of cryogenic anomalies, which make the Earth atmosphere and the entire Earth system very special, if not unique, objects in the universe.

  17. Hawking radiation of black rings from anomalies

    International Nuclear Information System (INIS)

    Chen Bin; He Wei

    2008-01-01

    We derive Hawking radiation of five-dimensional black rings from gauge and gravitational anomalies using the method proposed by Robinson and Wilczek. We find, as in the black hole case, that the problem could reduce to a (1+1)-dimensional field theory and the anomalies result in correct Hawking temperature for neutral, dipole and charged black rings

  18. Clinical Study of Second Branchial Cleft Anomalies.

    Science.gov (United States)

    Lee, Dong Hoon; Yoon, Tae Mi; Lee, Joon Kyoo; Lim, Sang Chul

    2018-03-30

    The objective of this study was to review the clinical characteristics and surgical treatment outcomes of second branchial cleft anomalies, and to evaluate the usefulness and accuracy of preoperative fine-needle aspiration cytology (FNAC) in the diagnosis of branchial cleft cysts. A retrospective chart review was performed at Chonnam National University Hwasun Hospital from January 2010 to December 2016. Among 25 patients with second branchial cleft anomalies, in 23 patients (92.0%), these anomalies presented as cysts, and in the remaining 2 patients (8.0%), these anomalies presented as fistulas. Fine-needle aspiration cytology had a diagnostic sensitivity of 100%, a positive-predictive value of 100%, and accuracy of 100% for diagnosing second branchial cleft cyst. All patients of second branchial cleft anomalies were treated surgically under general anesthesia. No recurrence of second branchial cleft anomalies was observed. Branchial cleft cysts were the most common type of second branchial cleft anomalies. Preoperative FNAC is a useful and accurate method for preoperative evaluation of branchial cleft cysts. Surgical excision of second branchial cleft anomalies is the treatment of choice without any complications and with no recurrence.

  19. Praenatalt diagnosticeret hydronefrose og andre urologiske anomalier

    DEFF Research Database (Denmark)

    Cortes, Dina; Jørgensen, Troels Munch; Rittig, Søren

    2006-01-01

    By renal ultrasound examination, urological anomalies may be demonstrated in 1-2% of fetuses and in about 0.5% of newborns. Boys have about twice the frequency of girls. Surgical treatment is indicated in about one fourth of these urological anomalies. If all pregnant women in Denmark were to hav...

  20. Hamiltonian formulation of anomaly free chiral bosons

    International Nuclear Information System (INIS)

    Abdalla, E.; Abdalla, M.C.B.; Devecchi, F.P.; Zadra, A.

    1988-01-01

    Starting out of an anomaly free Lagrangian formulation for chiral scalars, which a Wess-Zumino Term (to cancel the anomaly), we formulate the corresponding hamiltonian problem. Ther we use the (quantum) Siegel invariance to choose a particular, which turns out coincide with the obtained by Floreanini and Jackiw. (author) [pt

  1. Improved prenatal detection of chromosomal anomalies

    DEFF Research Database (Denmark)

    Frøslev-Friis, Christina; Hjort-Pedersen, Karina; Henriques, Carsten U

    2011-01-01

    Prenatal screening for karyotype anomalies takes place in most European countries. In Denmark, the screening method was changed in 2005. The aim of this study was to study the trends in prevalence and prenatal detection rates of chromosome anomalies and Down syndrome (DS) over a 22-year period....

  2. Anomalies of Nuclear Criticality, Revision 6

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, E. D.; Prichard, Andrew W.; Durst, Bonita E.; Erickson, David; Puigh, Raymond J.

    2010-02-19

    This report is revision 6 of the Anomalies of Nuclear Criticality. This report is required reading for the training of criticality professionals in many organizations both nationally and internationally. This report describes many different classes of nuclear criticality anomalies that are different than expected.

  3. Cutaneous vascular anomalies associated with neural tube defects: nomenclature and pathology revisited.

    Science.gov (United States)

    Maugans, Todd; Sheridan, Rachel M; Adams, Denise; Gupta, Anita

    2011-07-01

    Lumbosacral cutaneous vascular anomalies associated with neural tube defects are frequently described in the literature as "hemangiomas." The classification system for pediatric vascular anomalies developed by the International Society for the Study of Vascular Anomalies provides a framework to accurately diagnose these lesions. To apply this classification to vascular cutaneous anomalies overlying myelodysplasias. A retrospective analysis of patients with neural tube defects and lumbosacral cutaneous vascular lesions was performed. All eligible patients had detailed histopathologic analysis of skin and spinal cord/placode lesions. Clinical and radiologic features were analyzed. Conventional histology and GLUT-1 immunostaining were performed to differentiate infantile capillary hemangiomas from capillary vascular malformations. Ten cases with cutaneous lesions associated with neural tube defects were reviewed. Five lesions were diagnosed as infantile capillary hemangiomas based upon histology and positive GLUT-1 endothelial reactivity. These lesions had a strong association with dermal sinus tracts. No reoperations were required for residual intraspinal vascular lesions, and overlying cutaneous vascular anomalies involuted with time. The remaining 5 lesions were diagnosed as capillary malformations. These occurred with both open and closed neural tube defects, did not involute, and demonstrated enlargement and darkening due to vascular congestion. The International Society for the Study of Vascular Anomalies scheme should be used to describe the cutaneous vascular lesions associated with neural tube defects: infantile capillary hemangiomas and capillary malformations. We advocate that these lesions be described as "vascular anomalies" or "stains" pending accurate diagnosis by clinical, histological, and immunohistochemical evaluations.

  4. Sea surface temperature anomalies in the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    RameshKumar, M.R.

    temperature anomalies for the above regions respectively. An analysis has shown that most of the short duration anomalies (i.e., anomalies with periods less than 4 months) are driven by the surface heat fluxes. The medium duration anomalies (i.e., anomalies...

  5. Vibrational anomalies and marginal stability of glasses

    KAUST Repository

    Marruzzo, Alessia

    2013-01-01

    The experimentally measured vibrational spectrum of glasses strongly deviates from that expected in Debye\\'s elasticity theory: The density of states deviates from Debye\\'s ω2 law ("boson peak"), the sound velocity shows a negative dispersion in the boson-peak frequency regime, and there is a strong increase in the sound attenuation near the boson-peak frequency. A generalized elasticity theory is presented, based on the model assumption that the shear modulus of the disordered medium fluctuates randomly in space. The fluctuations are assumed to be uncorrelated and have a certain distribution (Gaussian or otherwise). Using field-theoretical techniques one is able to derive mean-field theories for the vibrational spectrum of a disordered system. The theory based on a Gaussian distribution uses a self-consistent Born approximation (SCBA),while the theory for non-Gaussian distributions is based on a coherent-potential approximation (CPA). Both approximate theories appear to be saddle-point approximations of effective replica field theories. The theory gives a satisfactory explanation of the vibrational anomalies in glasses. Excellent agreement of the SCBA theory with simulation data on a soft-sphere glass is reached. Since the SCBA is based on a Gaussian distribution of local shear moduli, including negative values, this theory describes a shear instability as a function of the variance of shear fluctuations. In the vicinity of this instability, a fractal frequency dependence of the density of states and the sound attenuation ∝ ω1+a is predicted with a ≲ 1/2. Such a frequency dependence is indeed observed both in simulations and in experimental data. We argue that the observed frequency dependence stems from marginally stable regions in a glass and discuss these findings in terms of rigidity percolation. © 2013 EDP Sciences and Springer.

  6. Intracranial developmental venous anomaly: is it asymptomatic?

    Science.gov (United States)

    Puente, A Bolívar; de Asís Bravo Rodríguez, F; Bravo Rey, I; Romero, E Roldán

    2018-03-16

    Intracranial developmental venous anomalies are the most common vascular malformation. In the immense majority of cases, these anomalies are asymptomatic and discovered incidentally, and they are considered benign. Very exceptionally, however, they can cause neurological symptoms. In this article, we present three cases of patients with developmental venous anomalies that presented with different symptoms owing to complications derived from altered venous drainage. These anomalies were located in the left insula, right temporal lobe, and cerebellum. The exceptionality of the cases presented as well as of the images associated, which show the mechanism through which the symptoms developed, lies in the low incidence of symptomatic developmental venous anomalies reported in the literature. Copyright © 2018 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  7. Lunar Bouguer gravity anomalies - Imbrian age craters

    Science.gov (United States)

    Dvorak, J.; Phillips, R. J.

    1978-01-01

    The Bouguer gravity of mass anomalies associated with four Imbrian age craters, analyzed in the present paper, are found to differ considerably from the values of the mass anomalies associated with some young lunar craters. Of the Imbrian age craters, only Piccolomini exhibits a negative gravity anomaly (i.e., a low density region) which is characteristic of the young craters studied. The Bouguer gravity anomalies are zero for each of the remaining Imbrian age craters. Since, Piccolomini is younger, or at least less modified, than the other Imbrian age craters, it is suggested that the processes responsible for the post-impact modification of the Imbrian age craters may also be responsible for removing the negative mass anomalies initially associated with these features.

  8. Analyticity properties of Graham-Witten anomalies

    International Nuclear Information System (INIS)

    Asnin, Vadim

    2008-01-01

    Analytic properties of Graham-Witten anomalies are considered. Weyl anomalies according to their analytic properties are of type A (coming from δ-singularities in correlators of several energy-momentum tensors) or of type B (originating in counterterms which depend logarithmically on a mass scale). It is argued that all Graham-Witten anomalies can be divided into two groups, internal and external, and that all external anomalies are of type B, whereas among internal anomalies there is one term of type A and all the rest are of type B. This argument is checked explicitly for the case of a free scalar field in a six-dimensional space with a two-dimensional submanifold

  9. Congenital anomalies and normal skeletal variants

    International Nuclear Information System (INIS)

    Guebert, G.M.; Yochum, T.R.; Rowe, L.J.

    1987-01-01

    Congenital anomalies and normal skeletal variants are a common occurrence in clinical practice. In this chapter a large number of skeletal anomalies of the spine and pelvis are reviewed. Some of the more common skeletal anomalies of the extremities are also presented. The second section of this chapter deals with normal skeletal variants. Some of these variants may simulate certain disease processes. In some instances there are no clear-cut distinctions between skeletal variants and anomalies; therefore, there may be some overlap of material. The congenital anomalies are presented initially with accompanying text, photos, and references, beginning with the skull and proceeding caudally through the spine to then include the pelvis and extremities. The normal skeletal variants section is presented in an anatomical atlas format without text or references

  10. Congenital anomalies of the spine: radiologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jung Kyu; Kim, Sang Won; Ryu, Kyung Nam [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

    2003-04-01

    Congenital anomalies of the spine are frequent and variable. Some are restricted to skeletal structures, while others involve combine neural tube defects or are associated with other multi-systemic disorders. Structural spinal anomalies can be classified according to their location: 1) the vertebral body, 2) the articular process, 3) the lamina with spinous process, 4) the pars interarticularis, 5) the facet joint, 6) the pedicle, or 7) other. Because of similarities between these congenital anomalies and (a) secondary changes involving infection or joint disease and (b) deformities resulting from trauma and uncertain tumorous conditions, significant confusion can occur during diagnosis. Moreover, since the anomalies often give rise to both functional impairment and cosmetic problem, appropriate treatment relies crucially on accurate diagnosis. The authors illustrate the pathogenesis and radiologic findings of the relatively common spinal anomalies confined to skeletal structures.

  11. Regional magnetic anomaly constraints on continental rifting

    Science.gov (United States)

    Vonfrese, R. R. B.; Hinze, W. J.; Olivier, R.; Bentley, C. R.

    1985-01-01

    Radially polarized MAGSAT anomalies of North and South America, Europe, Africa, India, Australia and Antarctica demonstrate remarkably detailed correlation of regional magnetic lithospheric sources across rifted margins when plotted on a reconstruction of Pangea. These major magnetic features apparently preserve their integrity until a superimposed metamorphoric event alters the magnitude and pattern of the anomalies. The longevity of continental scale magnetic anomalies contrasts markedly with that of regional gravity anomalies which tend to reflect predominantly isostatic adjustments associated with neo-tectonism. First observed as a result of NASA's magnetic satellite programs, these anomalies provide new and fundamental constraints on the geologic evolution and dynamics of the continents and oceans. Accordingly, satellite magnetic observations provide a further tool for investigating continental drift to compliment other lines of evidence in paleoclimatology, paleontology, paleomagnetism, and studies of the radiometric ages and geometric fit of the continents.

  12. Global magnetic anomaly and aurora of Neptune

    International Nuclear Information System (INIS)

    Cheng, A.F.

    1990-01-01

    The large offset and tilt of Neptune's dipole magnetic field combine to create a global magnetic anomaly, analogous to but much more important than Earth's South Atlantic Anomaly. Energetic particle precipitation loss within the Neptune anomaly creates atmospheric drift shadows within which particle fluxes are greatly reduced. The energetic particle dropout observed by Voyager near closest approach occurred near the predicted times when Voyager passed within the atmospheric drift shadow. Extremely soft, structured bursts of ions and electrons within the drift shadow may result from plasma wave-induced pitch angle scattering of trapped particles confined near the magnetic equator. The dropout does not necessarily imply that Voyager passed through an Earth-like discrete auroral zone, as earlier reported. The ion and electron fluxes observed within the dropout period correspond to particles that must precipitate to Neptune's atmosphere within the anomaly region. This anomaly precipitation can account for a major portion of the ultraviolet emissions previously identified as Neptune aurora

  13. MR imaging of neuronal migration anomaly

    International Nuclear Information System (INIS)

    Hong, Hyun Sook; Choi, Eun Wan; Kim, Dae Ho; Chung, Moo Chan; Kwon, Kuy Hyang; Kim, Ki Jung

    1991-01-01

    Abnormalities of neuronal migration are characterized by anectopic location of neurons in the cerebral cortex. This broad group of anomalies includes agyria, pachygyria, schizencephaly, unilateral megalencephaly, and gray matter heterotopia. Patients with this anomaly present clinically with a variety of symptoms which are proportional to the extent of the brain involved. These abnormalities have characterized pathologically in vivo by sonography and CT scan. MR appears to be an imaging technique of choice in evaluating these anomalies because it is capable of exceptionally good differentiation between gray and white matter, high contrast resolution, multiplanar display of the anatomy, and lack of overlying bone artifac. The purpose of this paper is to describe the MR findings of neuronal migration anomaly. The results of our study support that MR appears to be the imaging method of choice for diagnosing migration anomalies and the primary screening method for infants or children who have seisure/and delayed development

  14. Deep Sources: New constraints on the tectonic origin of the Klyuchevskoy Group upper mantle anomaly

    Science.gov (United States)

    Bourke, J. R.; Nikulin, A.; Levin, V. L.

    2017-12-01

    Volcanoes of the Klyuchevskoy Group (KG) form one of the most active volcanic clusters on the planet, yet its position relative to the subducting Pacific Plate seems to be in violation of the understood principles of the flux-induced arc volcanism. Positioned at 170km above the accepted subduction contact, the KG is seemingly outside the maximum fluid flux release zone of 100km, as observed across global subduction zone environments. Past geophysical studies indicate presence of a planar seismic anomaly 110km below the KG, and it has been noted that the KG lavas exhibit anomalous geochemical signatures, possibly associated with two separate melt generation regions. This interpretation was largely based on receiver function analysis of seismic data recorded by 3 stations of the Partnership in International Research and Education (PIRE) network, done prior to this data becoming publically available. We present results of receiver function and a teleseismic, regional, and local source shear wave splitting study, focused on datasets obtained by the full PIRE network of 12 stations, as well as a hybrid summation of all stations. We present our findings in the form of depth migrated receiver function images convolved with a three-dimensional model of the subduction zone and shear-wave splitting measurements. Our results vastly increase the resolution of the previously identified upper mantle anomaly, further constraining its geometry both vertically and laterally. We complement our observations with a forward modeling effort aimed at assessing the geological nature of the anomaly. Specifically, we test three scenarios that were previously invoked to explain the presence of the low-velocity anomaly in the upper mantle below the KG: a 3D flow of mantle material around the corner of the subducting Pacific Plate, a sinking paleoslab left behind as a result of subduction rollback, and a plume of sediments from the subducting plate. We show that presence of remnant paleoslab

  15. Strong intrinsic motivation

    OpenAIRE

    Dessi, Roberta; Rustichini, Aldo

    2015-01-01

    A large literature in psychology, and more recently in economics, has argued that monetary rewards can reduce intrinsic motivation. We investigate whether the negative impact persists when intrinsic motivation is strong, and test this hypothesis experimentally focusing on the motivation to undertake interesting and challenging tasks, informative about individual ability. We find that this type of task can generate strong intrinsic motivation, that is impervious to the effect of monetary incen...

  16. Bitcoin Meets Strong Consistency

    OpenAIRE

    Decker, Christian; Seidel, Jochen; Wattenhofer, Roger

    2014-01-01

    The Bitcoin system only provides eventual consistency. For everyday life, the time to confirm a Bitcoin transaction is prohibitively slow. In this paper we propose a new system, built on the Bitcoin blockchain, which enables strong consistency. Our system, PeerCensus, acts as a certification authority, manages peer identities in a peer-to-peer network, and ultimately enhances Bitcoin and similar systems with strong consistency. Our extensive analysis shows that PeerCensus is in a secure state...

  17. Strong gravity and supersymmetry

    International Nuclear Information System (INIS)

    Chamseddine, Ali H.; Salam, A.; Strathdee, J.

    1977-11-01

    A supersymmetric theory is constructed for a strong f plus a weak g graviton, together with their accompanying massive gravitinos, by gaugin the gradel 0Sp(2,2,1)x 0Sp(2,2,1) structure. The mixing term between f and g fields, which makes the strong graviton massive, can be introduced through a spontaneous symmetry-breaking mechanism implemented in this note by constructing a non-linear realization of the symmetry group

  18. The Association of H1N1 Pandemic Influenza with Congenital Anomaly Prevalence in Europe

    DEFF Research Database (Denmark)

    Luteijn, Johannes Michiel; Addor, Marie-Claude; Arriola, Larraitz

    2015-01-01

    BACKGROUND: In the context of the European Surveillance of Congenital Anomalies (EUROCAT) surveillance response to the 2009 influenza pandemic, we sought to establish whether there was a detectable increase of congenital anomaly prevalence among pregnancies exposed to influenza seasons in general......, and whether any increase was greater during the 2009 pandemic than during other seasons. METHODS: We performed an ecologic time series analysis based on 26,967 pregnancies with nonchromosomal congenital anomaly conceived from January 2007 to March 2011, reported by 15 EUROCAT registries. Analysis...... and tricuspid atresia and stenosis during pandemic influenza season 2009, but not during 2007-2011 influenza seasons. For congenital anomalies, where there was no prior hypothesis, the prevalence of tetralogy of Fallot was strongly reduced during influenza seasons. CONCLUSIONS: Our data do not suggest...

  19. Anomaly Detection in Dynamic Networks

    Energy Technology Data Exchange (ETDEWEB)

    Turcotte, Melissa [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-10-14

    Anomaly detection in dynamic communication networks has many important security applications. These networks can be extremely large and so detecting any changes in their structure can be computationally challenging; hence, computationally fast, parallelisable methods for monitoring the network are paramount. For this reason the methods presented here use independent node and edge based models to detect locally anomalous substructures within communication networks. As a first stage, the aim is to detect changes in the data streams arising from node or edge communications. Throughout the thesis simple, conjugate Bayesian models for counting processes are used to model these data streams. A second stage of analysis can then be performed on a much reduced subset of the network comprising nodes and edges which have been identified as potentially anomalous in the first stage. The first method assumes communications in a network arise from an inhomogeneous Poisson process with piecewise constant intensity. Anomaly detection is then treated as a changepoint problem on the intensities. The changepoint model is extended to incorporate seasonal behavior inherent in communication networks. This seasonal behavior is also viewed as a changepoint problem acting on a piecewise constant Poisson process. In a static time frame, inference is made on this extended model via a Gibbs sampling strategy. In a sequential time frame, where the data arrive as a stream, a novel, fast Sequential Monte Carlo (SMC) algorithm is introduced to sample from the sequence of posterior distributions of the change points over time. A second method is considered for monitoring communications in a large scale computer network. The usage patterns in these types of networks are very bursty in nature and don’t fit a Poisson process model. For tractable inference, discrete time models are considered, where the data are aggregated into discrete time periods and probability models are fitted to the

  20. Ferromagnetic spin coupling as the origin of 0.7 anomaly in quantum point contacts.

    Science.gov (United States)

    Aryanpour, K; Han, J E

    2009-02-06

    We study one-dimensional itinerant electron models with ferromagnetic coupling to investigate the origin of the 0.7 anomaly in quantum point contacts. Linear conductance calculations from the quantum Monte Carlo technique for spin interactions of different spatial range suggest that 0.7(2e;{2}/h) anomaly results from a strong interaction of low-density conduction electrons to ferromagnetic fluctuations formed across the potential barrier. The conductance plateau appears due to the strong incoherent scattering at high temperature when the electron traversal time matches the time scale of dynamic ferromagnetic excitations.

  1. Lunar magnetic anomalies detected by the Apollo substatellite magnetometers

    Science.gov (United States)

    Hood, L.L.; Coleman, P.J.; Russell, C.T.; Wilhelms, D.E.

    1979-01-01

    Properties of lunar crustal magnetization thus far deduced from Apollo subsatellite magnetometer data are reviewed using two of the most accurate presently available magnetic anomaly maps - one covering a portion of the lunar near side and the other a part of the far side. The largest single anomaly found within the region of coverage on the near-side map correlates exactly with a conspicuous, light-colored marking in western Oceanus Procellarum called Reiner Gamma. This feature is interpreted as an unusual deposit of ejecta from secondary craters of the large nearby primary impact crater Cavalerius. An age for Cavalerius (and, by implication, for Reiner Gamma) of 3.2 ?? 0.2 ?? 109 y is estimated. The main (30 ?? 60 km) Reiner Gamma deposit is nearly uniformly magnetized in a single direction, with a minimum mean magnetization intensity of ???7 ?? 10-2 G cm3/g (assuming a density of 3 g/cm3), or about 700 times the stable magnetization component of the most magnetic returned samples. Additional medium-amplitude anomalies exist over the Fra Mauro Formation (Imbrium basin ejecta emplaced ???3.9 ?? 109 y ago) where it has not been flooded by mare basalt flows, but are nearly absent over the maria and over the craters Copernicus, Kepler, and Reiner and their encircling ejecta mantles. The mean altitude of the far-side anomaly gap is much higher than that of the near-side map and the surface geology is more complex, so individual anomaly sources have not yet been identified. However, it is clear that a concentration of especially strong sources exists in the vicinity of the craters Van de Graaff and Aitken. Numerical modeling of the associated fields reveals that the source locations do not correspond with the larger primary impact craters of the region and, by analogy with Reiner Gamma, may be less conspicuous secondary crater ejecta deposits. The reason for a special concentration of strong sources in the Van de Graaff-Aitken region is unknown, but may be indirectly

  2. Anomalies, Unitarity and Quantum Irreversibility

    CERN Document Server

    Anselmi, D

    1999-01-01

    The trace anomaly in external gravity is the sum of three terms at criticality: the square of the Weyl tensor, the Euler density and Box R, with coefficients, properly normalized, called c, a and a', the latter being ambiguously defined by an additive constant. Unitarity and positivity properties of the induced actions allow us to show that the total RG flows of a and a' are equal and therefore the a'-ambiguity can be consistently removed through the identification a'=a. The picture that emerges clarifies several long-standing issues. The interplay between unitarity and renormalization implies that the flux of the renormalization group is irreversible. A monotonically decreasing a-function interpolating between the appropriate values is naturally provided by a'. The total a-flow is expressed non-perturbatively as the invariant (i.e. scheme-independent) area of the graph of the beta function between the fixed points. We test this prediction to the fourth loop order in perturbation theory, in QCD with Nf ~< ...

  3. Data Mining for Anomaly Detection

    Science.gov (United States)

    Biswas, Gautam; Mack, Daniel; Mylaraswamy, Dinkar; Bharadwaj, Raj

    2013-01-01

    The Vehicle Integrated Prognostics Reasoner (VIPR) program describes methods for enhanced diagnostics as well as a prognostic extension to current state of art Aircraft Diagnostic and Maintenance System (ADMS). VIPR introduced a new anomaly detection function for discovering previously undetected and undocumented situations, where there are clear deviations from nominal behavior. Once a baseline (nominal model of operations) is established, the detection and analysis is split between on-aircraft outlier generation and off-aircraft expert analysis to characterize and classify events that may not have been anticipated by individual system providers. Offline expert analysis is supported by data curation and data mining algorithms that can be applied in the contexts of supervised learning methods and unsupervised learning. In this report, we discuss efficient methods to implement the Kolmogorov complexity measure using compression algorithms, and run a systematic empirical analysis to determine the best compression measure. Our experiments established that the combination of the DZIP compression algorithm and CiDM distance measure provides the best results for capturing relevant properties of time series data encountered in aircraft operations. This combination was used as the basis for developing an unsupervised learning algorithm to define "nominal" flight segments using historical flight segments.

  4. Collie Eye Anomaly in Switzerland.

    Science.gov (United States)

    Walser-Reinhardt, L; Hässig, M; Spiess, B

    2009-12-01

    In this retrospective study, the results of 3'527 eye examinations in 6 different breeds affected with Collie Eye Anomaly (CEA) over a period of 8 years (1999 - 2007) are described. CEA was divided into three main ophthalmoscopic features, a) choroidal hypoplasia (CRH), b) CRH and coloboma and c) coloboma alone. Of the 101 Smooth Collies 8.9 % showed signs of CRH, whereas 36.9 % of Rough Collies were affected with CRH, 2.8 % with CRH and coloboma and 0.38 % with coloboma alone. Choroidal hypoplasia was present in 13.1 %, CRH and coloboma in 1.8 % and coloboma alone in 0.2 % of the Shetland Sheepdogs. Only one Australian Shepherd dog had CRH, while 0.7 % of the Border Collies were affected with CRH. None of the Nova Scotia Duck Tolling Retrievers were affected with CEA. There were no statistically significant differences in the occurrence of CEA between males and females, nor was there any relation between coat colors. Significant differences could be shown between dogs younger or older than 8 weeks at first examination. CEA was more often diagnosed in dogs younger than 8 weeks within the Rough Collie and Shetland Sheepdog.

  5. The antilock braking system anomaly: a drinking driver problem?

    Science.gov (United States)

    Harless, David W; Hoffer, George E

    2002-05-01

    Antilock braking systems (ABS) have held promise for reducing the incidence of accidents because they reduce stopping times on slippery surfaces and allow drivers to maintain steering control during emergency braking. Farmer et al. (Accident Anal. Prevent. 29 (1997) 745) provide evidence that antilock brakes are beneficial to nonoccupants: a set of 1992 model General Motors vehicles equipped with antilock brakes were involved in significantly fewer fatal crashes in which occupants of other vehicles, pedestrians, or bicyclists were killed. But, perversely, the risk of death for occupants of vehicles equipped with antilock brakes increased significantly after adoption. Farmer (Accident Anal. Prevent. 33 (2001) 361) updates the analysis for 1996- 1998 and finds a significant attenuation in the ABS anomaly. Researchers have put forward two hypotheses to explain this antilock brake anomaly: risk compensation and improper operation of antilock brake-equipped vehicles. We provide strong evidence for the improper operation hypothesis by showing that the antilock brake anomaly is confined largely to drinking drivers. Further, we show that the attenuation phenomenon occurs consistently after the first three to four years of vehicle service.

  6. Phonon anomalies in trilayer high-Tc cuprate superconductors

    International Nuclear Information System (INIS)

    Dubroka, Adam; Munzar, Dominik

    2004-01-01

    We present an extension of the model proposed recently to account for dramatic chAes below T c (anomalies) of some c-axis polarized infrared-active phonons in bilayer cuprate superconductors, that applies to trilayer high-T c compounds. We discuss several types of phonon anomalies that can occur in these systems and demonstrate that our model is capable of explaining the spectral chAes occurring upon entering the superconducting state in the trilayer compound Tl 2 Ba 2 Ca 2 Cu 3 O 10 . The low-temperature spectra of this compound obtained by Zetterer and coworkers display an additional broad absorption band, similar to the one observed in underdoped YBa 2 Cu 3 O 7-δ and Bi 2 Sr 2 CaCu 2 O 8 . In addition, three phonon modes are strongly anomalous. We attribute the absorption band to the transverse Josephson plasma resonance, similar to that of the bilayer compounds. The phonon anomalies are shown to result from a modification of the local fields induced by the formation of the resonance. The spectral chAes in Tl 2 Ba 2 Ca 2 Cu 3 O 10 are compared with those occurring in Bi 2 Sr 2 Ca 2 Cu 3 O 10 , reported recently by Boris and coworkers

  7. Effect of geomagnetic storm conditions on the equatorial ionization anomaly and equatorial temperature anomaly

    Science.gov (United States)

    Bharti, Gaurav; Bag, T.; Sunil Krishna, M. V.

    2018-03-01

    The effect of the geomagnetic storm on the equatorial ionization anomaly (EIA) and equatorial temperature anomaly (ETA) has been studied using the atomic oxygen dayglow emissions at 577.7 nm (OI 557.7 nm) and 732.0 nm (OII 732.0 nm). For the purpose of this study, four intense geomagnetic storms during the ascending phase of solar cycle 24 have been considered. This study is primarily based on the results obtained using photochemical models with necessary inputs from theoretical studies and experimental observations. The latest reaction rate coefficients, quantum yields and the corresponding cross-sections have also been incorporated in these models. The volume emission rate of airglow emissions has been calculated using the neutral densities from NRLMSISE-00 and charged densities from IRI-2012 model. The modeled volume emission rate (VER) for OI 557.7 nm shows a positive correlation with the Dst index at 150 km and negative correlation with Dst at 250 and 280 km altitudes. Latitudinal profile of the greenline emission rate at different altitudes show a distinct behaviour similar to what has been observed in EIA with crests on either sides of the equator. The EIA crests are found to show poleward movement in the higher altitude regions. The volume emission rate of 732.0 nm emission shows a strong enhancement during the main phase of the storm. The changes observed in the airglow emission rates are explained with the help of variations induced in neutral densities and parameters related to EIA and ETA. The latitudinal variation of 732.0 nm emission rate is correlated to the variability in EIA during the storm period.

  8. Occurrence and Detectability of Thermal Anomalies on Europa

    Science.gov (United States)

    Hayne, Paul O.; Christensen, Philip R.; Spencer, John R.; Abramov, Oleg; Howett, Carly; Mellon, Michael; Nimmo, Francis; Piqueux, Sylvain; Rathbun, Julie A.

    2017-10-01

    Endogenic activity is likely on Europa, given its young surface age of and ongoing tidal heating by Jupiter. Temperature is a fundamental signature of activity, as witnessed on Enceladus, where plumes emanate from vents with strongly elevated temperatures. Recent observations suggest the presence of similar water plumes at Europa. Even if plumes are uncommon, resurfacing may produce elevated surface temperatures, perhaps due to near-surface liquid water. Detecting endogenic activity on Europa is one of the primary mission objectives of NASA’s planned Europa Clipper flyby mission.Here, we use a probabilistic model to assess the likelihood of detectable thermal anomalies on the surface of Europa. The Europa Thermal Emission Imaging System (E-THEMIS) investigation is designed to characterize Europa’s thermal behavior and identify any thermal anomalies due to recent or ongoing activity. We define “detectability” on the basis of expected E-THEMIS measurements, which include multi-spectral infrared emission, both day and night.Thermal anomalies on Europa may take a variety of forms, depending on the resurfacing style, frequency, and duration of events: 1) subsurface melting due to hot spots, 2) shear heating on faults, and 3) eruptions of liquid water or warm ice on the surface. We use numerical and analytical models to estimate temperatures for these features. Once activity ceases, lifetimes of thermal anomalies are estimated to be 100 - 1000 yr. On average, Europa’s 10 - 100 Myr surface age implies a resurfacing rate of ~3 - 30 km2/yr. The typical size of resurfacing features determines their frequency of occurrence. For example, if ~100 km2 chaos features dominate recent resurfacing, we expect one event every few years to decades. Smaller features, such as double-ridges, may be active much more frequently. We model each feature type as a statistically independent event, with probabilities weighted by their observed coverage of Europa’s surface. Our results

  9. Branchial anomalies in the pediatric population.

    Science.gov (United States)

    Schroeder, James W; Mohyuddin, Nadia; Maddalozzo, John

    2007-08-01

    We sought to review the presentation, evaluation, and treatment of branchial anomalies in the pediatric population and to relate these findings to recurrences and complications. We conducted a retrospective study at a tertiary care pediatric hospital. Ninety-seven pediatric patients who were treated for branchial anomalies over a 10-year period were reviewed. Patients were studied if they underwent surgical treatment for the branchial anomaly and had 1 year of postoperative follow-up; 67 children met criteria, and 74 anomalies were studied. Patients with cysts presented at a later age than did those with branchial anomaly fistulas or sinus branchial anomalies. 32% of branchial anomalies were previously infected. Of these, 71% had more than one preoperative infection. 18% of the BA were first arch derivatives, 69% were second arch derivatives and 7% were third arch derivatives. There were 22 branchial cysts, 31 branchial sinuses and 16 branchial fistulas. The preoperative and postoperative diagnoses differed in 17 cases. None of the excised specimens that contained a cystic lining recurred; all five recurrences had multiple preoperative infections. Recurrence rates are increased when there are multiple preoperative infections and when there is no epithelial lining identified in the specimen.

  10. Congenital hand anomalies in Upper Egypt

    Directory of Open Access Journals (Sweden)

    Tarek Abulezz

    2016-01-01

    Full Text Available Background: Congenital hand anomalies are numerous and markedly variant. Their significance is attributed to the frequent occurrence and their serious social, psychological and functional impacts on patient's life. Patients and Methods: This is a follow-up study of 64 patients with hand anomalies of variable severity. All patients were presented to Plastic Surgery Department of Sohag University Hospital in a period of 24 months. Results: This study revealed that failure of differentiation and duplication deformities were the most frequent, with polydactyly was the most common anomaly encountered. The mean age of presentation was 6 years and female to male ratio was 1.46:1. Hand anomalies were either isolated, associated with other anomalies or part of a syndrome. Conclusion: Incidence of congenital hand anomalies in Upper Egypt is difficult to be estimated due to social and cultural concepts, lack of education, poor registration and deficient medical survey. Management of hand anomalies should be individualised, carefully planned and started as early as possible to achieve the best outcome.

  11. Dynamical supersymmetry breaking and gauge anomalies

    International Nuclear Information System (INIS)

    Zhang, H.

    1991-01-01

    Some aspects of supersymmetric gauge theories are discussed. It is shown that dynamical supersymmetry breaking does not occur in supersymmetric QED in higher dimensions. The cancellation of both local (perturbative) and global (non-perturbative) gauge anomalies are also discussed in supersymmetric gauge theories. We argue that there is no dynamical supersymmetry breaking in higher dimensions in any supersymmetric gauge theories free of gauge anomalies. It is also shown that for supersymmetric gauge theories in higher dimensions with a compact connected simple gauge group, when the local anomaly-free condition is satisfied, there can be at most a possible Z 2 global gauge anomaly in extended supersymmetric SO(10) (or spin (10)) gauge theories in D=10 dimensions containing additional Weyl fermions in a spinor representation of SO(10) (or spin (10)). In four dimensions with local anomaly-free condition satisfied, the only possible global gauge anomalies in supersymmetric gauge theories are Z 2 global gauge anomalies for extended supersymmetric SP(2N) (N=rank) gauge theories containing additional Weyl fermions in a representation of SP(2N) with an odd 2nd-order Dynkin index. (orig.)

  12. Hamiltonian Anomalies from Extended Field Theories

    Science.gov (United States)

    Monnier, Samuel

    2015-09-01

    We develop a proposal by Freed to see anomalous field theories as relative field theories, namely field theories taking value in a field theory in one dimension higher, the anomaly field theory. We show that when the anomaly field theory is extended down to codimension 2, familiar facts about Hamiltonian anomalies can be naturally recovered, such as the fact that the anomalous symmetry group admits only a projective representation on the Hilbert space, or that the latter is really an abelian bundle gerbe over the moduli space. We include in the discussion the case of non-invertible anomaly field theories, which is relevant to six-dimensional (2, 0) superconformal theories. In this case, we show that the Hamiltonian anomaly is characterized by a degree 2 non-abelian group cohomology class, associated to the non-abelian gerbe playing the role of the state space of the anomalous theory. We construct Dai-Freed theories, governing the anomalies of chiral fermionic theories, and Wess-Zumino theories, governing the anomalies of Wess-Zumino terms and self-dual field theories, as extended field theories down to codimension 2.

  13. MR imaging of paediatric uterovaginal anomalies

    International Nuclear Information System (INIS)

    Lang, I.M.; Babyn, P.; Oliver, G.D.

    1999-01-01

    Background. Transabdominal ultrasound (US) has not proved completely reliable in Muellerian duct anomalies. One study has shown it useful in obstructed uterovaginal anomalies. We are unaware of a study that has used endovaginal ultrasound in children to investigate uterovaginal anomalies. Magnetic resonance imaging (MRI) is now gaining wide acceptance in imaging congenital abnormalities of the genital tract. Objective. To identify the problems and potential pitfalls of using MRI to evaluate the female genital tract in paediatric patients. Materials and methods. A retrospective review of the MRI scans of 19 patients, aged 3 months to 19 years (mean 14 years), with uterovaginal anomalies. Results. The uterovaginal anomalies were categorised into three groups: (1) congenital absence of the Muellerian ducts, or the Mayer-Rokitansky-Kuster-Hauser syndrome (n = 7), (2) disorders of vertical fusion (n = 2) and (3) disorders of lateral fusion (n = 10). Conclusions. MRI is a reliable method for evaluating paediatric uterovaginal anomalies, but should be analysed in conjunction with other imaging modalities (US and genitography). Previous surgery makes interpretation more difficult and, if possible, MRI should be carried out prior to any surgery. An accurate MRI examination can be extremely helpful prior to surgery and it is important for the radiologist to have knowledge of how these complex anomalies are managed and what pitfalls to avoid. (orig.)

  14. Development of the experimental procedure to examine the response of carbon fiber-reinforced polymer composites subjected to a high-intensity pulsed electric field and low-velocity impact.

    Science.gov (United States)

    Hart, Robert J; Zhupanska, Olesya I

    2016-01-01

    A new fully automated experimental setup has been developed to study the response of carbon fiber reinforced polymer (CFRP) composites subjected to a high-intensity pulsed electric field and low-velocity impact. The experimental setup allows for real-time measurements of the pulsed electric current, voltage, impact load, and displacements on the CFRP composite specimens. The setup includes a new custom-built current pulse generator that utilizes a bank of capacitor modules capable of producing a 20 ms current pulse with an amplitude of up to 2500 A. The setup enabled application of the pulsed current and impact load and successfully achieved coordination between the peak of the current pulse and the peak of the impact load. A series of electrical, impact, and coordinated electrical-impact characterization tests were performed on 32-ply IM7/977-3 unidirectional CFRP composites to assess their ability to withstand application of a pulsed electric current and determine the effects of the pulsed current on the impact response. Experimental results revealed that the electrical resistance of CFRP composites decreased with an increase in the electric current magnitude. It was also found that the electrified CFRP specimens withstood higher average impact loads compared to the non-electrified specimens.

  15. Analysis of renal anomalies in VACTERL association.

    Science.gov (United States)

    Cunningham, Bridget K; Khromykh, Alina; Martinez, Ariel F; Carney, Tyler; Hadley, Donald W; Solomon, Benjamin D

    2014-10-01

    VACTERL association refers to a combination of congenital anomalies that can include: vertebral anomalies, anal atresia, cardiac malformations, tracheo-esophageal fistula with esophageal atresia, renal anomalies (typically structural renal anomalies), and limb anomalies. We conducted a description of a case series to characterize renal findings in a cohort of patients with VACTERL association. Out of the overall cohort, 48 patients (with at least three component features of VACTERL and who had abdominal ultrasound performed) met criteria for analysis. Four other patients were additionally analyzed separately, with the hypothesis that subtle renal system anomalies may occur in patients who would not otherwise meet criteria for VACTERL association. Thirty-three (69%) of the 48 patients had a clinical manifestation affecting the renal system. The most common renal manifestation (RM) was vesicoureteral reflux (VUR) in addition to a structural defect (present in 27%), followed by unilateral renal agenesis (24%), and then dysplastic/multicystic kidneys or duplicated collected system (18% for each). Twenty-two (88%) of the 25 patients with a structural RM had an associated anorectal malformation. Individuals with either isolated lower anatomic anomalies, or both upper and lower anatomic anomalies were not statistically more likely to have a structural renal defect than those with isolated upper anatomic anomalies (p = 0.22, p = 0.284, respectively). Given the high prevalence of isolated VUR in our cohort, we recommend a screening VCUG or other imaging modality be obtained to evaluate for VUR if initial renal ultrasound shows evidence of obstruction or renal scarring, as well as ongoing evaluation of renal health. © 2014 Wiley Periodicals, Inc.

  16. Prevalence of dental anomalies in Indian population.

    Science.gov (United States)

    Patil, Santosh; Doni, Bharati; Kaswan, Sumita; Rahman, Farzan

    2013-10-01

    Developmental anomalies of the dentition are not infrequently observed by the dental practitioner. The aim of the present study was to determine the prevalence of dental anomalies in the Indian population. A retrospective study of 4133 panoramic radiographs of patients, who attended the Department of Oral Medicine and Radiology, Jodhpur Dental College General Hospital between September 2008 to December 2012 was done. The ages of the patients ranged from 13 to 38 years with a mean age of 21.8 years. The orthopantomographs (OPGs) and dental records were examined for any unusual finding such as congenitally missing teeth, impactions, ectopic eruption, supernumerary teeth, odontoma, dilacerations, taurodontism, dens in dente, germination and fusion, among others. 1519 (36.7%) patients had at least one dental anomaly. The congenitally missing teeth 673 (16.3%) had the highest prevalence, followed by impacted teeth 641 (15.5%), supernumerary teeth 51 (1.2%) and microdontia 41 (1.0%). Other anomalies were found at lower prevalence ranging from transposition 7 (0.1%) to ectopic eruption 30 (0.7%). The most prevalent anomaly in the Indian population was congenitally missing teeth (16.3%), and the second frequent anomaly was impacted teeth (15.5%), whereas, macrodontia, odontoma and transposition were the least frequent anomalies, with a prevalence of 0.2%, 0.2% and 0.1% respectively. While the overall prevalence of these anomalies may be low, the early diagnosis is imperative for the patient management and treatment planning. Key words:Dental anomaly, prevalence, panoramic radiography.

  17. Minimal quantization of two-dimensional models with chiral anomalies

    International Nuclear Information System (INIS)

    Ilieva, N.

    1987-01-01

    Two-dimensional gauge models with chiral anomalies - ''left-handed'' QED and the chiral Schwinger model, are quantized consistently in the frames of the minimal quantization method. The choice of the cone time as a physical time for system of quantization is motivated. The well-known mass spectrum is found but with a fixed value of the regularization parameter a=2. Such a unique solution is obtained due to the strong requirement of consistency of the minimal quantization that reflects in the physically motivated choice of the time axis

  18. B-decay anomalies in Pati-Salam SU(4)

    Science.gov (United States)

    Barbieri, Riccardo; Tesi, Andrea

    2018-03-01

    Attempts to incorporate in a coherent picture the B-decay anomalies presumably observed in b→ c and b→ s semi-leptonic decays have to face the absence of signals in other related experiments, both at low and at high energies. By extending and making more precise the content of Barbieri et al. (Eur Phys J C 77(1):8, 2017), we describe one such attempt based on the Pati-Salam SU(4) group, that unifies colour and the B- L charge, in the context of a new strongly interacting sector, equally responsible for producing a pseudo-Goldstone Higgs boson.

  19. Structure of gauge and gravitational anomalies*

    International Nuclear Information System (INIS)

    Alvarez-Gaume, L.; Ginsparg, P.

    1985-01-01

    It is shown how the form of the gauge and gravitational anomalies in quantum field theories may be derived from classical index theorems. The gravitational anomaly in both Einstein and Lorentz form is considered and their equivalence is exhibited. The formalism of gauge and gravitational theories is reviewed using the language of differential geometry, and notions from the theory of characteristic classes necessary for understanding the classical index theorems are introduced. The treatment of known topological results includes a pedagogical derivation of the Wess-Zumino effective Lagrangian in abitrary even dimension. The relation between various forms of the anomaly present in the literature is also clarified

  20. Simple recipe for holographic Weyl anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Bugini, F. [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Concepción,Casilla 160-C, Concepción (Chile); Diaz, D.E. [Departamento de Ciencias Físicas, Facultad de Ciencias Exactas, Universidad Andres Bello,Autopista Concepción-Talcahuano 7100, Talcahuano (Chile)

    2017-04-20

    We propose a recipe — arguably the simplest — to compute the holographic type-B Weyl anomaly for general higher-derivative gravity in asymptotically AdS spacetimes. In 5 and 7 dimensions we identify a suitable basis of curvature invariants that allows to read off easily, without any further computation, the Weyl anomaly coefficients of the dual CFT. We tabulate the contributions from quadratic, cubic and quartic purely algebraic curvature invariants and also from terms involving derivatives of the curvature. We provide few examples, where the anomaly coefficients have been obtained by other means, to illustrate the effectiveness of our prescription.

  1. Using EVT for Geological Anomaly Design and Its Application in Identifying Anomalies in Mining Areas

    Directory of Open Access Journals (Sweden)

    Feilong Qin

    2016-01-01

    Full Text Available A geological anomaly is the basis of mineral deposit prediction. Through the study of the knowledge and characteristics of geological anomalies, the category of extreme value theory (EVT to which a geological anomaly belongs can be determined. Associating the principle of the EVT and ensuring the methods of the shape parameter and scale parameter for the generalized Pareto distribution (GPD, the methods to select the threshold of the GPD can be studied. This paper designs a new algorithm called the EVT model of geological anomaly. These study data on Cu and Au originate from 26 exploration lines of the Jiguanzui Cu-Au mining area in Hubei, China. The proposed EVT model of the geological anomaly is applied to identify anomalies in the Jiguanzui Cu-Au mining area. The results show that the model can effectively identify the geological anomaly region of Cu and Au. The anomaly region of Cu and Au is consistent with the range of ore bodies of actual engineering exploration. Therefore, the EVT model of the geological anomaly can effectively identify anomalies, and it has a high indicating function with respect to ore prospecting.

  2. Atmospheric circulation patterns and phenological anomalies of grapevine in Italy

    Science.gov (United States)

    Cola, Gabriele; Alilla, Roberta; Dal Monte, Giovanni; Epifani, Chiara; Mariani, Luigi; Parisi, Simone Gabriele

    2014-05-01

    Grapevine (Vitis vinifera L.) is a fundamental crop for Italian agriculture as testified by the first place of Italy in the world producers ranking. This justify the importance of quantitative analyses referred to this crucial crop and aimed to quantify meteorological resources and limitations to development and production. Phenological rhythms of grapevine are strongly affected by surface fields of air temperature which in their turn are affected by synoptic circulation. This evidence highlights the importance of an approach based on dynamic climatology in order to detect and explain phenological anomalies that can have relevant effects on quantity and quality of grapevine production. In this context, this research is aimed to study the existing relation among the 850 hPa circulation patterns over the Euro-Mediterranean area from NOAA Ncep dataset and grapevine phenological fields for Italy over the period 2006-2013, highlighting the main phenological anomalies and analyzing synoptic determinants. This work is based on phenological fields with a standard pixel of 2 km routinely produced from 2006 by the Iphen project (Italian Phenological network) on the base of phenological observations spatialized by means of a specific algorithm based on cumulated thermal resources expressed as Normal Heat Hours (NHH). Anomalies have been evaluated with reference to phenological normal fields defined for the Italian area on the base of phenological observations and Iphen model. Results show that relevant phenological anomalies observed over the reference period are primarily associated with long lasting blocking systems driving cold air masses (Arctic or Polar-Continental) or hot ones (Sub-Tropical) towards the Italian area. Specific cases are presented for some years like 2007 and 2011.

  3. Strongly interacting Fermi gases

    Directory of Open Access Journals (Sweden)

    Bakr W.

    2013-08-01

    Full Text Available Strongly interacting gases of ultracold fermions have become an amazingly rich test-bed for many-body theories of fermionic matter. Here we present our recent experiments on these systems. Firstly, we discuss high-precision measurements on the thermodynamics of a strongly interacting Fermi gas across the superfluid transition. The onset of superfluidity is directly observed in the compressibility, the chemical potential, the entropy, and the heat capacity. Our measurements provide benchmarks for current many-body theories on strongly interacting fermions. Secondly, we have studied the evolution of fermion pairing from three to two dimensions in these gases, relating to the physics of layered superconductors. In the presence of p-wave interactions, Fermi gases are predicted to display toplogical superfluidity carrying Majorana edge states. Two possible avenues in this direction are discussed, our creation and direct observation of spin-orbit coupling in Fermi gases and the creation of fermionic molecules of 23Na 40K that will feature strong dipolar interactions in their absolute ground state.

  4. A strong comeback

    International Nuclear Information System (INIS)

    Marier, D.

    1992-01-01

    This article presents the results of a financial rankings survey which show a strong economic activity in the independent energy industry. The topics of the article include advisor turnover, overseas banks, and the increase in public offerings. The article identifies the top project finance investors for new projects and restructurings and rankings for lenders

  5. Quantum anomalies in nodal line semimetals

    Science.gov (United States)

    Burkov, A. A.

    2018-04-01

    Topological semimetals are a new class of condensed matter systems with nontrivial electronic structure topology. Their unusual observable properties may often be understood in terms of quantum anomalies. In particular, Weyl and Dirac semimetals, which have point band-touching nodes, are characterized by the chiral anomaly, which leads to the Fermi arc surface states, anomalous Hall effect, negative longitudinal magnetoresistance, and planar Hall effect. In this paper, we explore analogous phenomena in nodal line semimetals. We demonstrate that such semimetals realize a three-dimensional analog of the parity anomaly, which is a known property of two-dimensional Dirac semimetals arising, for example, on the surface of a three-dimensional topological insulator. We relate one of the characteristic properties of nodal line semimetals, namely, the drumhead surface states, to this anomaly, and derive the field theory, which encodes the corresponding anomalous response.

  6. Chiral anomalies in higher dimensional supersymmetric theories

    International Nuclear Information System (INIS)

    Bonora, L.; Pasti, P.; Tonin, M.

    1987-01-01

    We derive explicit formulas for pure gauge anomalies in a SYM theory in 6D as well as in 10D. Each anomaly consists of two terms: a gauge cocycle and a cocycle of the superdiffeomorphisms. The derivation is based essentially on a remarkable property of supersymmetric theories which we call Weil triviality and is directly connected with the constraints. The analogous problem for Lorentz anomalies is stated in the same way. However, in general, there are difficulties concerning Weil triviality. We prove that for pure SUGRA in 6D as well as in 10D it is possible to prove Weil triviality and, consequently, to obtain explict expressions for pure Lorentz anomalies. However, as far as SUGRA coupled to SYM a la Chapline-Manton or a la Green-Schwarz is concerned, no self-evident solution is available. (orig.)

  7. Mexico Terrain Corrected Free Air Anomalies (97)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This 2' gravity anomaly grid for Mexico, North-Central America and the Western Caribbean Sea is NOT the input data set used in the development of the MEXICO97 model....

  8. SEG US Bouguer Gravity Anomaly Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The SEG gravity data are the product of the ad hoc Gravity Anomaly Map (GAM) Committee, sponsored by the Society of Exploration Geophysicists (SEG) and the U.S....

  9. Conformal anomalies in curved space--time

    Energy Technology Data Exchange (ETDEWEB)

    Duncan, A.

    1976-11-01

    The general form of the conformal anomaly in a dimensionally regularized theory of massless fermions in a background metric is shown to be determined by the first few terms of weak field perturbation theory.

  10. Magnetic anomalies in Central Bengal fan

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, T.C.S.; Lakshminarayana, S.; Sarma, K.V.L.N.S.

    Total magnetic field anomalies recorded over the Central Bengal Fan are analysed and the depths to the magnetic basement are computed using the analytical signal and the Werner deconvolution methods. To the west and east of 85 degrees E...

  11. Quantum machine learning for quantum anomaly detection

    Science.gov (United States)

    Liu, Nana; Rebentrost, Patrick

    2018-04-01

    Anomaly detection is used for identifying data that deviate from "normal" data patterns. Its usage on classical data finds diverse applications in many important areas such as finance, fraud detection, medical diagnoses, data cleaning, and surveillance. With the advent of quantum technologies, anomaly detection of quantum data, in the form of quantum states, may become an important component of quantum applications. Machine-learning algorithms are playing pivotal roles in anomaly detection using classical data. Two widely used algorithms are the kernel principal component analysis and the one-class support vector machine. We find corresponding quantum algorithms to detect anomalies in quantum states. We show that these two quantum algorithms can be performed using resources that are logarithmic in the dimensionality of quantum states. For pure quantum states, these resources can also be logarithmic in the number of quantum states used for training the machine-learning algorithm. This makes these algorithms potentially applicable to big quantum data applications.

  12. Deconstruction and reconstruction of an anomaly

    Czech Academy of Sciences Publication Activity Database

    Engelmann, Dirk; Strobel, M.

    2012-01-01

    Roč. 76, č. 2 (2012), s. 678-689 ISSN 0899-8256 Institutional support: RVO:67985998 Keywords : anomalies * false consensus * information processing Subject RIV: AH - Economics Impact factor: 1.000, year: 2012

  13. Ionospheric Anomaly before Kyushu|Japan Earthquake

    Directory of Open Access Journals (Sweden)

    YANG Li

    2017-05-01

    Full Text Available GIM data released by IGS is used in the article and a new method of combining the Sliding Time Window Method and the Ionospheric TEC correlation analysis method of adjacent grid points is proposed to study the relationship between pre-earthquake ionospheric anomalies and earthquake. By analyzing the abnormal change of TEC in the 5 grid points around the seismic region, the abnormal change of ionospheric TEC is found before the earthquake and the correlation between the TEC sequences of lattice points is significantly affected by earthquake. Based on the analysis of the spatial distribution of TEC anomaly, anomalies of 6 h, 12 h and 6 h were found near the epicenter three days before the earthquake. Finally, ionospheric tomographic technology is used to do tomographic inversion on electron density. And the distribution of the electron density in the ionospheric anomaly is further analyzed.

  14. Detection of cardiovascular anomalies: Hybrid systems approach

    KAUST Repository

    Ledezma, Fernando; Laleg-Kirati, Taous-Meriem

    2012-01-01

    In this paper, we propose a hybrid interpretation of the cardiovascular system. Based on a model proposed by Simaan et al. (2009), we study the problem of detecting cardiovascular anomalies that can be caused by variations in some physiological

  15. Residual generator for cardiovascular anomalies detection

    KAUST Repository

    Belkhatir, Zehor; Laleg-Kirati, Taous-Meriem; Tadjine, Mohamed

    2014-01-01

    This paper discusses the possibility of using observer-based approaches for cardiovascular anomalies detection and isolation. We consider a lumped parameter model of the cardiovascular system that can be written in a form of nonlinear state

  16. Strong Electroweak Symmetry Breaking

    CERN Document Server

    Grinstein, Benjamin

    2011-01-01

    Models of spontaneous breaking of electroweak symmetry by a strong interaction do not have fine tuning/hierarchy problem. They are conceptually elegant and use the only mechanism of spontaneous breaking of a gauge symmetry that is known to occur in nature. The simplest model, minimal technicolor with extended technicolor interactions, is appealing because one can calculate by scaling up from QCD. But it is ruled out on many counts: inappropriately low quark and lepton masses (or excessive FCNC), bad electroweak data fits, light scalar and vector states, etc. However, nature may not choose the minimal model and then we are stuck: except possibly through lattice simulations, we are unable to compute and test the models. In the LHC era it therefore makes sense to abandon specific models (of strong EW breaking) and concentrate on generic features that may indicate discovery. The Technicolor Straw Man is not a model but a parametrized search strategy inspired by a remarkable generic feature of walking technicolor,...

  17. Perturbative and global anomalies in supergravity theories

    International Nuclear Information System (INIS)

    Sezgin, E.

    1986-09-01

    Perturbative and global anomalies in supergravity theories are reviewed. The existence of a matter and gauge coupled supergravity theory in six dimensions with E 6 xE 7 xU(1) symmetry and highly nontrivial anomaly cancellations is emphasised. The possible string origin of this theory is posed as an open problem, study of which may lead to discovery of new ways to construct/compactify heterotic superstrings. (author)

  18. Reports on various anomalies of the ribs

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, G.; Brix, F.

    1988-02-01

    Three patients are presented who were suffering from different anomalies of the ribs: There was one each plus and minus variant and a female patient with Gorlin-Goltz syndrome (basal cell nevus syndrome) demonstrating several changes in the ribs as an expression of a genetically determined segmentation disturbance. These presentations are followed by a detailed discussion on the types and causes of such anomalies.

  19. Reports on various anomalies of the ribs

    International Nuclear Information System (INIS)

    Brinkmann, G.; Brix, F.

    1988-01-01

    Three patients are presented who were suffering from different anomalies of the ribs: There was one each plus and minus variant and a female patient with Gorlin-Goltz syndrome (basal cell nevus syndrome) demonstrating several changes in the ribs as an expression of a genetically determined segmentation disturbance. These presentations are followed by a detailed discussion on the types and causes of such anomalies. (orig.) [de

  20. Satellite magnetic anomalies of the Antarctic crust

    Directory of Open Access Journals (Sweden)

    D. E. Alsdorf

    2000-06-01

    Full Text Available Spatially and temporally static crustal magnetic anomalies are contaminated by static core field effects above spherical harmonic degree 12 and dynamic, large-amplitude external fields. To extract crustal magnetic anomalies from the measurements of NASA's Magsat mission, we separate crustal signals from both core and external field effects. In particular, we define Magsat anomalies relative to the degree 11 field and use spectral correlation theory to reduce them for external field effects. We obtain a model of Antarctic crustal thickness by comparing the region's terrain gravity effects to free-air gravity anomalies derived from the Earth Gravity Model 1996 (EGM96. To separate core and crustal magnetic effects, we obtain the pseudo-magnetic effect of the crustal thickness variations from their gravity effect via Poisson's theorem for correlative potentials. We compare the pseudo-magnetic effect of the crustal thickness variations to field differences between degrees 11 and 13 by spectral correlation analysis. We thus identify and remove possible residual core field effects in the Magsat anomalies relative to the degree 11 core field. The resultant anomalies reflect possible Antarctic contrasts due both to crustal thickness and intracrustal variations of magnetization. In addition, they provide important constraints on the geologic interpretation of aeromagnetic survey data, such as are available for the Weddell Province. These crustal anomalies also may be used to correct for long wavelength errors in regional compilations of near-surface magnetic survey data. However, the validity of these applications is limited by the poor quality of the Antarctic Magsat data that were obtained during austral Summer and Fall when south polar external field activity was maximum. Hence an important test and supplement for the Antarctic crustal Magsat anomaly map will be provided by the data from the recently launched Ørsted mission, which will yield coverage

  1. Neutrino scattering and the reactor antineutrino anomaly

    Science.gov (United States)

    Garcés, Estela; Cañas, Blanca; Miranda, Omar; Parada, Alexander

    2017-12-01

    Low energy threshold reactor experiments have the potential to give insight into the light sterile neutrino signal provided by the reactor antineutrino anomaly and the gallium anomaly. In this work we analyze short baseline reactor experiments that detect by elastic neutrino electron scattering in the context of a light sterile neutrino signal. We also analyze the sensitivity of experimental proposals of coherent elastic neutrino nucleus scattering (CENNS) detectors in order to exclude or confirm the sterile neutrino signal with reactor antineutrinos.

  2. Prevalence of dental anomalies in Indian population

    OpenAIRE

    Santosh, Patil; Bharati, Doni; Sumita, Kaswan; Farzan, Rahman

    2013-01-01

    Objectives: Developmental anomalies of the dentition are not infrequently observed by the dental practitioner. The aim of the present study was to determine the prevalence of dental anomalies in the Indian population. Study Design: A retrospective study of 4133 panoramic radiographs of patients, who attended the Department of Oral Medicine and Radiology, Jodhpur Dental College General Hospital between September 2008 to December 2012 was done. The ages of the patients ranged from 13 to 38 year...

  3. Modular invariance, chiral anomalies and contact terms

    International Nuclear Information System (INIS)

    Kutasov, D.

    1988-03-01

    The chiral anomaly in heterotic strings with full and partial modular invariance in D=2n+2 dimensions is calculated. The boundary terms which were present in previous calculations are shown to be cancelled in the modular invariant case by contact terms, which can be obtained by an appropriate analytic continuation. The relation to the low energy field theory is explained. In theories with partial modular invariance, an expression for the anomaly is obtained and shown to be non zero in general. (author)

  4. Plasmons in strong superconductors

    International Nuclear Information System (INIS)

    Baldo, M.; Ducoin, C.

    2011-01-01

    We present a study of the possible plasmon excitations that can occur in systems where strong superconductivity is present. In these systems the plasmon energy is comparable to or smaller than the pairing gap. As a prototype of these systems we consider the proton component of Neutron Star matter just below the crust when electron screening is not taken into account. For the realistic case we consider in detail the different aspects of the elementary excitations when the proton, electron components are considered within the Random-Phase Approximation generalized to the superfluid case, while the influence of the neutron component is considered only at qualitative level. Electron screening plays a major role in modifying the proton spectrum and spectral function. At the same time the electron plasmon is strongly modified and damped by the indirect coupling with the superfluid proton component, even at moderately low values of the gap. The excitation spectrum shows the interplay of the different components and their relevance for each excitation modes. The results are relevant for neutrino physics and thermodynamical processes in neutron stars. If electron screening is neglected, the spectral properties of the proton component show some resemblance with the physical situation in high-T c superconductors, and we briefly discuss similarities and differences in this connection. In a general prospect, the results of the study emphasize the role of Coulomb interaction in strong superconductors.

  5. Coronary artery anomalies in Turner Syndrome.

    Science.gov (United States)

    Viuff, Mette H; Trolle, Christian; Wen, Jan; Jensen, Jesper M; Nørgaard, Bjarne L; Gutmark, Ephraim J; Gutmark-Little, Iris; Mortensen, Kristian H; Gravholt, Claus Højbjerg; Andersen, Niels H

    Congenital heart disease, primarily involving the left-sided structures, is often seen in patients with Turner Syndrome. Moreover, a few case reports have indicated that coronary anomalies may be more prevalent in Turner Syndrome than in the normal population. We therefore set out to systematically investigate coronary arterial anatomy by computed tomographic coronary angiography (coronary CTA) in Turner Syndrome patients. Fifty consecutive women with Turner Syndrome (mean age 47 years [17-71]) underwent coronary CTA. Patients were compared with 25 gender-matched controls. Coronary anomaly was more frequent in patients with Turner Syndrome than in healthy controls [20% vs. 4% (p = 0.043)]. Nine out of ten abnormal cases had an anomalous left coronary artery anatomy (absent left main trunk, n = 7; circumflex artery originating from the right aortic sinus, n = 2). One case had a tubular origin of the right coronary artery above the aortic sinus. There was no correlation between the presence of coronary arterial anomalies and karyotype, bicuspid aortic valve, or other congenital heart defects. Coronary anomalies are highly prevalent in Turner Syndrome. The left coronary artery is predominantly affected, with an absent left main coronary artery being the most common anomaly. No hemodynamically relevant coronary anomalies were found. Copyright © 2016 Society of Cardiovascular Computed Tomography. All rights reserved.

  6. Clustering and Recurring Anomaly Identification: Recurring Anomaly Detection System (ReADS)

    Science.gov (United States)

    McIntosh, Dawn

    2006-01-01

    This viewgraph presentation reviews the Recurring Anomaly Detection System (ReADS). The Recurring Anomaly Detection System is a tool to analyze text reports, such as aviation reports and maintenance records: (1) Text clustering algorithms group large quantities of reports and documents; Reduces human error and fatigue (2) Identifies interconnected reports; Automates the discovery of possible recurring anomalies; (3) Provides a visualization of the clusters and recurring anomalies We have illustrated our techniques on data from Shuttle and ISS discrepancy reports, as well as ASRS data. ReADS has been integrated with a secure online search

  7. Semiclassical theory of the tunneling anomaly in partially spin-polarized compressible quantum Hall states

    Science.gov (United States)

    Chowdhury, Debanjan; Skinner, Brian; Lee, Patrick A.

    2018-05-01

    Electron tunneling into a system with strong interactions is known to exhibit an anomaly, in which the tunneling conductance vanishes continuously at low energy due to many-body interactions. Recent measurements have probed this anomaly in a quantum Hall bilayer of the half-filled Landau level, and shown that the anomaly apparently gets stronger as the half-filled Landau level is increasingly spin polarized. Motivated by this result, we construct a semiclassical hydrodynamic theory of the tunneling anomaly in terms of the charge-spreading action associated with tunneling between two copies of the Halperin-Lee-Read state with partial spin polarization. This theory is complementary to our recent work (D. Chowdhury, B. Skinner, and P. A. Lee, arXiv:1709.06091) where the electron spectral function was computed directly using an instanton-based approach. Our results show that the experimental observation cannot be understood within conventional theories of the tunneling anomaly, in which the spreading of the injected charge is driven by the mean-field Coulomb energy. However, we identify a qualitatively new regime, in which the mean-field Coulomb energy is effectively quenched and the tunneling anomaly is dominated by the finite compressibility of the composite Fermion liquid.

  8. Effects of a child with a craniofacial anomaly on stability of the parental relationship.

    Science.gov (United States)

    St John, Dane; Pai, Lori; Belfer, Myron L; Mulliken, John B

    2003-09-01

    The purpose of this study was to determine rates of divorce in parents of children with various types of craniofacial anomalies and to analyze possible confounding factors. A 29-question survey was sent to parents of all children evaluated in the Craniofacial Centre between 1992 and 1997. Parents were questioned regarding pre- and postnatal marital stability, whether the child's facial anomaly contributed to divorce, and involvement in the child's welfare. Using deformational posterior plagiocephaly as a control group, rates of divorce vs. non-divorce were compared for craniofacial anomalies, categorized as asymmetric (hemifacial microsomia, unilateral coronal synostosis, cleft lip, cleft lip/palate) or symmetric (syndromic-craniosynostosis, orbital hypertelorism, Treacher Collins syndrome). Major anomalies (hemifacial microsomia, craniosynostosis, orbital hypertelorism, Treacher Collins syndrome) were also compared to minor anomalies (cleft lip, cleft lip/palate). Surveys were sent to both parents in 412 families; 403 surveys were returned; and the results were evaluated in 275 families (67%). Frequency analysis demonstrated an overall divorce rate of 6.8% and 4.9% separation. Anomalies associated with the highest rate of divorce were hemifacial microsomia (24.0%), syndromic craniosynostosis (12.2%), and cleft lip/palate (6.8%). 79% of non-divorced couples reported a strong prenatal relationship, whereas 59% of divorced couples reported a problematic relationship. Following birth of the affected child, 47% of non-divorced couples responded that the bonds became stronger and 41% of divorced couples thought the relationship worsened. Two-sided Fisher exact test comparing control vs. all other anomalies showed significance (p=.030) for rates of divorce. Separation of anomalies into asymmetric vs. symmetric and major vs. minor categories demonstrated no significant difference in divorce rate (p>.05). The mother was more likely to become a child's primary caregiver

  9. Strongly intensive quantities

    International Nuclear Information System (INIS)

    Gorenstein, M. I.; Gazdzicki, M.

    2011-01-01

    Analysis of fluctuations of hadron production properties in collisions of relativistic particles profits from use of measurable intensive quantities which are independent of system size variations. The first family of such quantities was proposed in 1992; another is introduced in this paper. Furthermore we present a proof of independence of volume fluctuations for quantities from both families within the framework of the grand canonical ensemble. These quantities are referred to as strongly intensive ones. Influence of conservation laws and resonance decays is also discussed.

  10. Strong-coupling approximations

    International Nuclear Information System (INIS)

    Abbott, R.B.

    1984-03-01

    Standard path-integral techniques such as instanton calculations give good answers for weak-coupling problems, but become unreliable for strong-coupling. Here we consider a method of replacing the original potential by a suitably chosen harmonic oscillator potential. Physically this is motivated by the fact that potential barriers below the level of the ground-state energy of a quantum-mechanical system have little effect. Numerically, results are good, both for quantum-mechanical problems and for massive phi 4 field theory in 1 + 1 dimensions. 9 references, 6 figures

  11. Chromosomal study in newborn infants with congenital anomalies in ...

    African Journals Online (AJOL)

    Congenital anomalies were found in 103 cases with a prevalence of 2.06% with male to female ratio of 1.7:1. Skeletal system anomalies had the highestfrequency (37.9%), followed in descending order by chromosomal abnormalities (27.2%), circulatory system anomalies (22.3%), central nervous system (CNS) anomalies ...

  12. Marine magnetic anomalies off Ratnagiri, Western continental shelf of India

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, D.G.

    of magnetic anomalies. Two-dimensional model and spectral studies of these anomalies were carried out, and subsurface models of the geology in the area have been derived from anomalies at a number of places. The results suggest that the anomalies occur over a...

  13. Strongly disordered superconductors

    International Nuclear Information System (INIS)

    Muttalib, K.A.

    1982-01-01

    We examine some universal effects of strong non-magnetic disorder on the electron-phonon and electron-electron interactions in a superconductor. In particular we explicitly take into account the effect of slow diffusion of electrons in a disordered medium by working in an exact impurity eigenstate representation. We find that the normal diffusion of electrons characterized by a constant diffusion coefficient does not lead to any significant correction to the electron-phonon or the effective electron-electron interactions in a superconductor. We then consider sufficiently strong disorder where Anderson localization of electrons becomes important and determine the effect of localization on the electron-electron interactions. We find that due to localization, the diffusion of electrons becomes anomalous in the sense that the diffusion coefficient becomes scale dependent. This results in an increase in the effective electron-electron interaction with increasing disorder. We propose that this provides a natural explanation for the unusual sensitivity of the transition temperature T/sub c/ of the high T/sub c/ superconductors (T/sub c/ > 10 0 K) to damage effects

  14. Strong Coupling Holography

    CERN Document Server

    Dvali, Gia

    2009-01-01

    We show that whenever a 4-dimensional theory with N particle species emerges as a consistent low energy description of a 3-brane embedded in an asymptotically-flat (4+d)-dimensional space, the holographic scale of high-dimensional gravity sets the strong coupling scale of the 4D theory. This connection persists in the limit in which gravity can be consistently decoupled. We demonstrate this effect for orbifold planes, as well as for the solitonic branes and string theoretic D-branes. In all cases the emergence of a 4D strong coupling scale from bulk holography is a persistent phenomenon. The effect turns out to be insensitive even to such extreme deformations of the brane action that seemingly shield 4D theory from the bulk gravity effects. A well understood example of such deformation is given by large 4D Einstein term in the 3-brane action, which is known to suppress the strength of 5D gravity at short distances and change the 5D Newton's law into the four-dimensional one. Nevertheless, we observe that the ...

  15. In-medium proton-neutron mass difference and the systematics of the Nolen-Schiffer anomaly

    International Nuclear Information System (INIS)

    Cohen, T.D.; Furnstahl, R.J.; Banerjee, M.K.

    1991-01-01

    We investigate a recent suggestion that the Nolen-Schiffer anomaly can be resolved if the in-medium proton-neutron mass difference is substantially changed from its free space value. In a number of hadronic models, such an effect is a natural consequence of partial chiral restoration in the nuclear medium. This suggestion is meaningful in the context of a local-density approximation, which has strong implications for the systematics of the Nolen-Schiffer anomaly over a range of nuclei. We show that such a mechanism predicts both noticeable shell effects and modest variations in the anomaly as the nuclear size is changed

  16. LIGO: The strong belief

    CERN Multimedia

    Antonella Del Rosso

    2016-01-01

    Twenty years of designing, building and testing a number of innovative technologies, with the strong belief that the endeavour would lead to a historic breakthrough. The Bulletin publishes an abstract of the Courier’s interview with Barry Barish, one of the founding fathers of LIGO.   The plots show the signals of gravitational waves detected by the twin LIGO observatories at Livingston, Louisiana, and Hanford, Washington. (Image: Caltech/MIT/LIGO Lab) On 11 February, the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo collaborations published a historic paper in which they showed a gravitational signal emitted by the merger of two black holes. These results come after 20 years of hard work by a large collaboration of scientists operating the two LIGO observatories in the US. Barry Barish, Linde Professor of Physics, Emeritus at the California Institute of Technology and former Director of the Global Design Effort for the Internat...

  17. Strongly interacting Higgs bosons

    International Nuclear Information System (INIS)

    Appelquist, T.; Bernard, C.

    1980-01-01

    The sensitivity of present-energy weak interactions to a strongly interacting heavy-Higgs-boson sector is discussed. The gauged nonlinear sigma model, which is the limit of the linear model as the Higgs-boson mass goes to infinity, is used to organize and catalogue all possible heavy-Higgs-boson effects. As long as the SU(2)/sub L/ x SU(2)/sub R/ symmetry of the Higgs sector is preserved, these effects are found to be small, of the order of the square of the gauge coupling times logarithms (but not powers) of the Higgs-boson mass divided by the W mass. We work in the context of a simplified model with gauge group SU(2)/sub L/; the extension to SU(2)/sub L/ x U(1) is briefly discussed

  18. [Surgical treatment of first branchial cleft anomaly].

    Science.gov (United States)

    Xiao, Hongjun; Kong, Weijia; Gong, Shusheng; Wang, Jibao; Liu, Shiying; Shi, Hong

    2005-10-01

    To identify the clinical and anatomical presentations and to discuss the guidelines for surgical management of anomalies of the first branchial cleft. Twenty-one patients with first branchial cleft anomalies were treated in our department between January 1994 and December 2004, their clinical data were retrospectively analysed. Surgery was performed on all patients. Among them 13 were males and 8 females, ranging in age from 1.5 to 33 years with an average of 15 years. Anatomically, 3 types of first branchial cleft anomalies were identified: fistulas (n = 17), cysts (n = 2), and fistula combined with cyst (n = 2). Before definitive surgery, soma patients (n = 4) underwent incision and drainage for infection owing to the difficulties in diagnosing this anomaly. Methylthioninium Chloride was used in almost all cases for tracking the fistulous during operation. Wide exposure is necessary in many cases,and a standard parotidectomy incision allows adequate exposure of the anomaly and preservation of the facial nerve. Complete removal without complications depends on a good understanding of regional embryogenesis, an awareness of the different anatomical presentations, and a readiness to identify and protect the facial nerve during resection.

  19. Fourth branchial complex anomalies: a case series.

    Science.gov (United States)

    Shrime, Mark; Kacker, Ashutosh; Bent, John; Ward, Robert F

    2003-11-01

    Anomalies of the fourth branchial arch complex are exceedingly rare, with approximately forty cases reported in the literature since 1972. The authors report experience with six fourth arch anomalies. Retrospective chart review of six consecutive patients presenting to the pediatric otolaryngology service at a tertiary care center with anomalies referable to the fourth branchial arch. All six patients presented within the first or second decade of life. All six had left-sided disease. Four patients presented with recurrent neck infection, one with asymptomatic cervical masses, and one with a neck mass and respiratory compromise. One patient had prior surgery presented with a recurrence. Diagnosis of fourth arch anomalies was suggested or confirmed by computed tomography and flexible laryngoscopy. Treatment was surgical in five patients; one patient is awaiting surgery. Surgical procedures included resection of the mass and endoscopic cauterization of the inner opening of the cyst. The presentation of a cervical mass, especially with recurrent infections and especially on the left side, in a child in the first or second decade of life heightens suspicion for an anomaly of the fourth branchial arch. Diagnosis can be difficult, but is aided by the use of flexible laryngoscopy, Computed tomography (CT) scanning and ultrasonography. Surgical resection of the cyst and cauterization of its pyriform sinus opening should be undertaken to minimize recurrence.

  20. Dental Anomalies in a Brazilian Cleft Population.

    Science.gov (United States)

    Sá, Jamile; Mariano, Lorena C; Canguçu, Daiane; Coutinho, Thaynara S L; Hoshi, Ryuichi; Medrado, Alena Peixoto; Martelli-Junior, Hercílio; Coletta, Ricardo D; Reis, Silvia R A

    2016-11-01

      The aim of this study was to radiographically investigate the prevalence of dental anomalies outside the cleft area in a group of Brazilian patients with nonsyndromic cleft lip and/or palate (NSCL/P).   A retrospective analysis of 207 panoramic radiographs of patients with NSCL/P aged 12 to 45 years without history of tooth extraction and orthodontic treatment was performed.   Dental anomalies were found in 75.4% of the patients, and tooth agenesis (29.2%) and supernumerary tooth (2.6%) were the most common anomalies. The risk of agenesis was higher among the individuals with cleft palate (CP) compared with individuals with cleft lip (CL) and cleft lip and palate (CLP) (agenesis: CP versus CL: odds ratio 6.27, 95% confidence interval 2.21-17.8, P = .0003; CP versus CLP: odds ratio 2.94; 95% confidence interval 1.27-6.81, P = .01). The frequency of dental agenesis was higher in patients with unilateral complete CLP (agenesis: P dental agenesis (P dental anomalies in patients with NSCL/P was higher than that reported in overall population. This study found preferential associations between dental anomalies and specific extensions of NSCL/P, suggesting that dental agenesis and ectopic tooth may be part of oral cleft subphenotypes.

  1. EDITORIAL: Strongly correlated electron systems Strongly correlated electron systems

    Science.gov (United States)

    Ronning, Filip; Batista, Cristian

    2011-03-01

    Strongly correlated electrons is an exciting and diverse field in condensed matter physics. This special issue aims to capture some of that excitement and recent developments in the field. Given that this issue was inspired by the 2010 International Conference on Strongly Correlated Electron Systems (SCES 2010), we briefly give some history in order to place this issue in context. The 2010 International Conference on Strongly Correlated Electron Systems was held in Santa Fe, New Mexico, a reunion of sorts from the 1989 International Conference on the Physics of Highly Correlated Electron Systems that also convened in Santa Fe. SCES 2010—co-chaired by John Sarrao and Joe Thompson—followed the tradition of earlier conferences, in this century, hosted by Buzios (2008), Houston (2007), Vienna (2005), Karlsruhe (2004), Krakow (2002) and Ann Arbor (2001). Every three years since 1997, SCES has joined the International Conference on Magnetism (ICM), held in Recife (2000), Rome (2003), Kyoto (2006) and Karlsruhe (2009). Like its predecessors, SCES 2010 topics included strongly correlated f- and d-electron systems, heavy-fermion behaviors, quantum-phase transitions, non-Fermi liquid phenomena, unconventional superconductivity, and emergent states that arise from electronic correlations. Recent developments from studies of quantum magnetism and cold atoms complemented the traditional subjects and were included in SCES 2010. 2010 celebrated the 400th anniversary of Santa Fe as well as the birth of astronomy. So what's the connection to SCES? The Dutch invention of the first practical telescope and its use by Galileo in 1610 and subsequent years overturned dogma that the sun revolved about the earth. This revolutionary, and at the time heretical, conclusion required innovative combinations of new instrumentation, observation and mathematics. These same combinations are just as important 400 years later and are the foundation of scientific discoveries that were discussed

  2. Introduction to sigma model anomalies

    International Nuclear Information System (INIS)

    Nelson, P.

    1985-01-01

    This paper presents results dealing with the specific case in which a sigma model with fermions arises as a result of dynamical symmetry breakdown from some group G to a subgroup H. H may contain chiral symmetries protecting some fermions in a representation ρ H of H. In this case it may be impossible to quantize the remaining fermions in a way which reproduces the anomalous Ward identities of any underlying strongly-interacting gauge theory. The author concludes that this pattern of symmetry breakdown will not be realized in any such theory. The criterion in this case is local in character, since roughly speaking once the sigma model in question behaves for field configurations close to the vacuum base point in the internal mainfold is known, symmetry can be used to find how it behaves everywhere else

  3. Vacuum stability bounds in anomaly and gaugino mediated supersymmetry breaking models

    International Nuclear Information System (INIS)

    Gabrielli, Emidio; Huitu, Katri; Roy, Sourov

    2002-01-01

    We constrain the parameter space of the minimal and gaugino-assisted anomaly mediation, and gaugino mediation models by requiring that the electroweak vacuum corresponds to the deepest minimum of the scalar potential. In the framework of anomaly mediation models we find strong lower bounds on slepton and squark masses. In the gaugino mediation models the mass spectrum is forced to be at the TeV scale. We find extensive regions of the parameter space which are ruled out, even at low tanβ. The implications of these results on the g-2 of the muon are also analyzed

  4. Type II first branchial cleft anomaly.

    Science.gov (United States)

    Al-Mahdi, Akmam H; Al-Khurri, Luay E; Atto, Ghada Z; Dhaher, Ameer

    2013-01-01

    First branchial cleft anomaly is a rare disease of the head and neck. It accounts for less than 8% of all branchial abnormalities. It is classified into type I, which is thought to arise from the duplication of the membranous external ear canal and are composed of ectoderm only, and type II that have ectoderm and mesoderm. Because of its rarity, first branchial cleft anomaly is often misdiagnosed and results in inappropriate management. A 9-year-old girl presented to us with fistula in the submandibular region and discharge in the external ear. Under general anesthesia, complete surgical excision of the fistula tract was done through step-ladder approach, and the histopathologic examination confirmed the diagnosis of type II first branchial cleft anomaly.

  5. First branchial cleft anomalies: avoiding the misdiagnosis.

    Science.gov (United States)

    Kumar, Rajeev; Sikka, Kapil; Sagar, Prem; Kakkar, Aanchal; Thakar, Alok

    2013-07-01

    First branchial cleft anomalies are a very rare entities accounting for less than 1 % of all branchial cleft malformations. They are often misdiagnosed for other cystic lesions occurring in parotid gland and inadequately treated (incision and drainage or incomplete excision) leading to multiple recurrences. We report a series of four patients who were previously operated (incision and drainage) for misdiagnosed first branchial cleft anomalies with subsequent recurrences. All patients underwent superficial parotidectomy with complete tract excision using facial nerve monitoring to prevent iatrogenic injury because of extensive fibrosis. We discuss the literature pertaining to first branchial cleft anomalies, their varied presentations and their relationship to facial nerve in parotid gland and importance of facial nerve monitoring in revision surgery.

  6. Anomaly-based Network Intrusion Detection Methods

    Directory of Open Access Journals (Sweden)

    Pavel Nevlud

    2013-01-01

    Full Text Available The article deals with detection of network anomalies. Network anomalies include everything that is quite different from the normal operation. For detection of anomalies were used machine learning systems. Machine learning can be considered as a support or a limited type of artificial intelligence. A machine learning system usually starts with some knowledge and a corresponding knowledge organization so that it can interpret, analyse, and test the knowledge acquired. There are several machine learning techniques available. We tested Decision tree learning and Bayesian networks. The open source data-mining framework WEKA was the tool we used for testing the classify, cluster, association algorithms and for visualization of our results. The WEKA is a collection of machine learning algorithms for data mining tasks.

  7. Gauge Anomalies and Neutrino Seesaw Models

    CERN Document Server

    Neves Cebola, Luis Manuel

    Despite the success of the Standard Model concerning theoretical predictions, there are several experimental results that cannot be explained and there are reasons to believe that there exists new physics beyond it. Neutrino oscillations, and hence their masses, are examples of this. Experimentally it is known that neutrinos masses are quite small, when compared to all Standard Model particle masses. Among the theoretical possibilities to explain these tiny masses, the seesaw mechanism is a simple and well-motivated framework. In its minimal version, heavy particles are introduced that decouple from the theory in the early universe. To build consistent theories, classical symmetries need to be preserved at quantum level, so that there are no anomalies. The cancellation of these anomalies leads to constraints in the parameters of the theory. One attractive solution is to realize the anomaly cancellation through the modication of the gauge symmetry. In this thesis we present a short review of some features of t...

  8. Evaluation of fetal anomalies with MR imaging

    International Nuclear Information System (INIS)

    Benson, R.C.; Platt, L.D.; Colletti, P.M.; Raval, J.K.; Boswell, W.D. Jr.; Halls, J.M.

    1987-01-01

    Twenty pregnant women underwent MR imaging (0.5 T) after US disclosed a significant fetal anomaly. The ability of MR imaging to depict the abnormalities was assessed. Of 20 abnormalities, 17 were visualized with MR imaging. Abnormalities included conjoined twins, omphalocele, gastroschisis, hydrocephalus, hydronephrosis, fetal ascites, facial teratoma, anencephaly, bladder outlet obstruction, thanatophoric dwarfism, cystic, hygroma, and fetal ovarian cyst. Thirteen of 14 abnormalities in third-trimester fetuses were visualized, as were four of six abnormalities in second-trimester fetuses. Associated polyhydramnios or oligohydramnios was evident in six of six cases. Anomalies were best delineated with T1-weighted sequences. The study suggests that MR imaging is potentially useful as a complementary imaging modality in the evaluation of fetal anomalies

  9. SOX2 anophthalmia syndrome and dental anomalies.

    Science.gov (United States)

    Chacon-Camacho, Oscar Francisco; Fuerte-Flores, Bertha Irene; Ricardez-Marcial, Edgar F; Zenteno, Juan Carlos

    2015-11-01

    SOX2 anophthalmia syndrome is an uncommon autosomal dominant syndrome caused by mutations in the SOX2 gene and clinically characterized by severe eye malformations (anophthalmia/microphthalmia) and extraocular anomalies mainly involving brain, esophagus, and genitalia. In this work, a patient with the SOX2 anophthalmia syndrome and exhibiting a novel dental anomaly is described. SOX2 genotyping in this patient revealed an apparently de novo c.70del20 deletion, a commonly reported SOX2 mutation. A review of the phenotypic variation observed in patients carrying the recurrent SOX2 c.70del20 mutation is presented. Although dental anomalies are uncommonly reported in the SOX2 anophthalmia syndrome, we suggest that a dental examination should be performed in patients with SOX2 mutations. © 2015 Wiley Periodicals, Inc.

  10. N-Acetyl-2-Aminofluorene (AAF) Processing in Adult Rat Hepatocytes in Primary Culture Occurs by High-Affinity Low-Velocity and Low-Affinity High-Velocity AAF Metabolite-Forming Systems.

    Science.gov (United States)

    Koch, Katherine S; Moran, Tom; Shier, W Thomas; Leffert, Hyam L

    2018-05-01

    N-acetyl-2-aminofluorene (AAF) is a procarcinogen used widely in physiological investigations of chemical hepatocarcinogenesis. Its metabolic pathways have been described extensively, yet little is known about its biochemical processing, growth cycle expression, and pharmacological properties inside living hepatocytes-the principal cellular targets of this hepatocarcinogen. In this report, primary monolayer adult rat hepatocyte cultures and high specific-activity [ring G-3 H]-N-acetyl-2-aminofluorene were used to extend previous observations of metabolic activation of AAF by highly differentiated, proliferation-competent hepatocytes in long-term cultures. AAF metabolism proceeded by zero-order kinetics. Hepatocytes processed significant amounts of procarcinogen (≈12 μg AAF/106 cells/day). Five ring-hydroxylated and one deacetylated species of AAF were secreted into the culture media. Extracellular metabolite levels varied during the growth cycle (days 0-13), but their rank quantitative order was time invariant: 5-OH-AAF > 7-OH-AAF > 3-OH-AAF > N-OH-AAF > aminofluorene (AF) > 1-OH-AAF. Lineweaver-Burk analyses revealed two principal classes of metabolism: System I (high-affinity and low-velocity), Km[APPARENT] = 1.64 × 10-7  M and VMAX[APPARENT] = 0.1 nmol/106 cells/day and System II (low-affinity and high-velocity), Km[APPARENT] = 3.25 × 10-5  M and VMAX[APPARENT] = 1000 nmol/106 cells/day. A third system of metabolism of AAF to AF, with Km[APPARENT] and VMAX[APPARENT] constants of 9.6 × 10-5  M and 4.7 nmol/106 cells/day, was also observed. Evidence provided in this report and its companion paper suggests selective roles and intracellular locations for System I- and System II-mediated AAF metabolite formation during hepatocarcinogenesis, although some of the molecules and mechanisms responsible for multi-system processing remain to be fully defined.

  11. Strong-interaction nonuniversality

    International Nuclear Information System (INIS)

    Volkas, R.R.; Foot, R.; He, X.; Joshi, G.C.

    1989-01-01

    The universal QCD color theory is extended to an SU(3) 1 direct product SU(3) 2 direct product SU(3) 3 gauge theory, where quarks of the ith generation transform as triplets under SU(3)/sub i/ and singlets under the other two factors. The usual color group is then identified with the diagonal subgroup, which remains exact after symmetry breaking. The gauge bosons associated with the 16 broken generators then form two massive octets under ordinary color. The interactions between quarks and these heavy gluonlike particles are explicitly nonuniversal and thus an exploration of their physical implications allows us to shed light on the fundamental issue of strong-interaction universality. Nonuniversality and weak flavor mixing are shown to generate heavy-gluon-induced flavor-changing neutral currents. The phenomenology of these processes is studied, as they provide the major experimental constraint on the extended theory. Three symmetry-breaking scenarios are presented. The first has color breaking occurring at the weak scale, while the second and third divorce the two scales. The third model has the interesting feature of radiatively induced off-diagonal Kobayashi-Maskawa matrix elements

  12. John Strong (1941 - 2006)

    CERN Multimedia

    Wickens, F

    Our friend and colleague John Strong was cruelly taken from us by a brain tumour on Monday 31st July, a few days before his 65th birthday John started his career working with a group from Westfield College, under the leadership of Ted Bellamy. He obtained his PhD and spent the early part of his career on experiments at Rutherford Appleton Laboratory (RAL), but after the early 1970s his research was focussed on experiments in CERN. Over the years he made a number of notable contributions to experiments in CERN: The Omega spectrometer adopted a system John had originally developed for experiments at RAL using vidicon cameras to record the sparks in the spark chambers; He contributed to the success of NA1 and NA7, where he became heavily involved in the electronic trigger systems; He was responsible for the second level trigger system for the ALEPH detector and spent five years leading a team that designed and built the system, which ran for twelve years with only minor interventions. Following ALEPH he tur...

  13. Stirring Strongly Coupled Plasma

    CERN Document Server

    Fadafan, Kazem Bitaghsir; Rajagopal, Krishna; Wiedemann, Urs Achim

    2009-01-01

    We determine the energy it takes to move a test quark along a circle of radius L with angular frequency w through the strongly coupled plasma of N=4 supersymmetric Yang-Mills (SYM) theory. We find that for most values of L and w the energy deposited by stirring the plasma in this way is governed either by the drag force acting on a test quark moving through the plasma in a straight line with speed v=Lw or by the energy radiated by a quark in circular motion in the absence of any plasma, whichever is larger. There is a continuous crossover from the drag-dominated regime to the radiation-dominated regime. In the crossover regime we find evidence for significant destructive interference between energy loss due to drag and that due to radiation as if in vacuum. The rotating quark thus serves as a model system in which the relative strength of, and interplay between, two different mechanisms of parton energy loss is accessible via a controlled classical gravity calculation. We close by speculating on the implicati...

  14. Distribution of branchial anomalies in a paediatric Asian population.

    Science.gov (United States)

    Teo, Neville Wei Yang; Ibrahim, Shahrul Izham; Tan, Kun Kiaang Henry

    2015-04-01

    The objective of the present study was to review the distribution and incidence of branchial anomalies in an Asian paediatric population and highlight the challenges involved in the diagnosis of branchial anomalies. This was a retrospective chart review of all paediatric patients who underwent surgery for branchial anomalies in a tertiary paediatric hospital from August 2007 to November 2012. The clinical notes were correlated with preoperative radiological investigations, intraoperative findings and histology results. Branchial anomalies were classified based on the results of the review. A total of 28 children underwent surgery for 30 branchial anomalies during the review period. Two children had bilateral branchial anomalies requiring excision. Of the 30 branchial anomalies, 7 (23.3%) were first branchial anomalies, 5 (16.7%) were second branchial anomalies, 3 (10.0%) were third branchial anomalies, and 4 (13.3%) were fourth branchial anomalies (one of the four patients with fourth branchial anomalies had bilateral branchial anomalies). In addition, seven children had 8 (26.7%) branchial anomalies that were thought to originate from the pyriform sinus; however, we were unable to determine if these anomalies were from the third or fourth branchial arches. There was inadequate information on the remaining 3 (10.0%) branchial anomalies for classification. The incidence of second branchial anomalies appears to be lower in our Asian paediatric population, while that of third and fourth branchial anomalies was higher. Knowledge of embryology and the related anatomy of the branchial apparatus is crucial in the identification of the type of branchial anomaly.

  15. Heat flow anomalies and their interpretation

    Science.gov (United States)

    Chapman, David S.; Rybach, Ladislaus

    1985-12-01

    More than 10,000 heat flow determinations exist for the earth and the data set is growing steadily at about 450 observations per year. If heat flow is considered as a surface expression of geothermal processes at depth, the analysis of the data set should reveal properties of those thermal processes. They do, but on a variety of scales. For this review heat flow maps are classified by 4 different horizontal scales of 10 n km (n = 1, 2, 3 and 4) and attention is focussed on the interpretation of anomalies which appear with characteristic dimensions of 10 (n - 1) km in the respective representations. The largest scale of 10 4 km encompasses heat flow on a global scale. Global heat loss is 4 × 10 13 W and the process of sea floor spreading is the principal agent in delivering much of this heat to the surface. Correspondingly, active ocean ridge systems produce the most prominent heat flow anomalies at this scale with characteristic widths of 10 3 km. Shields, with similar dimensions, exhibit negative anomalies. The scale of 10 3 km includes continent wide displays. Heat flow patterns at this scale mimic tectonic units which have dimensions of a few times 10 2 km, although the thermal boundaries between these units are sometimes sharp. Heat flow anomalies at this scale also result from plate tectonic processes, and are associated with arc volcanism, back arc basins, hot spot traces, and continental rifting. There are major controversies about the extent to which these surface thermal provinces reflect upper mantle thermal conditions, and also about the origin and evolution of the thermal state of continental lithosphere. Beginning with map dimensions of 10 2 km thermal anomalies of scale 10 1 km, which have a definite crustal origin, become apparent. The origin may be tectonic, geologic, or hydrologic. Ten kilometers is a common wavelength of topographic relief which drives many groundwater flow systems producing thermal anomalies. The largest recognized continental

  16. [Megadolichobasilar anomaly causing acute deafness with vertigo].

    Science.gov (United States)

    Unkelbach, M H; Radeloff, A; Bink, A; Gstöttner, W; Ziemann, U

    2008-01-01

    Megadolichobasilar anomaly, a dilatant arteriopathy of the basilar artery attributable to chronic arterial hypertension, can cause cranial nerve compression syndromes of the cerebellopontine angle or infarcts of the vertebrobasilar circulation. In this paper, we report on a patient with known megadolichobasilar anomaly and a partially thrombosed fusiform aneurysm of the basilar artery, who presented with acute-onset vertigo and subsequent deafness due to thromboembolic occlusion of the labyrinthine artery. Because of the vascular origin of the patient's symptoms, his vertigo disappeared over time while the deafness persisted.

  17. Radioactive anomaly discrimination from spectral ratios

    Science.gov (United States)

    Maniscalco, James; Sjoden, Glenn; Chapman, Mac Clements

    2013-08-20

    A method for discriminating a radioactive anomaly from naturally occurring radioactive materials includes detecting a first number of gamma photons having energies in a first range of energy values within a predetermined period of time and detecting a second number of gamma photons having energies in a second range of energy values within the predetermined period of time. The method further includes determining, in a controller, a ratio of the first number of gamma photons having energies in the first range and the second number of gamma photons having energies in the second range, and determining that a radioactive anomaly is present when the ratio exceeds a threshold value.

  18. Congenital anomalies of the neonatal head

    International Nuclear Information System (INIS)

    Benson, C.B.; Teele, R.L.; Dobkin, G.R.; Fine, C.; Bundy, A.L.; Doubilet, P.M.

    1987-01-01

    US is a noninvasive modality that has proved highly valuable in the assessment of congenital intracranial anomalies in the neonate. The patterns of malformation must be familiar to those who obtain and interpret neonatal cranial sonograms. The authors present a variety of cases of congenital anomalies studied with US, including agenesis of the corpus callosum, Dandy-Walker malformation, occipital enecphalocele, congenital hydrocephalus, vein of Galen aneurysm, hydranencephaly, holoprosencephaly, absence of the septum pellucidum, schizencephaly, and hypoplastic cerebellum. Correlation with other radiographic modalities and pathologic follow-up, available in a majority of cases, is included

  19. Singlet deflected anomaly/gauge mediation

    International Nuclear Information System (INIS)

    Blas, J. de; Delgado, A.

    2012-01-01

    We study an extension of the standard anomaly/gauge mediation scenario where the messenger fields have direct interactions with an extra gauge singlet. This realizes a phenomenologically viable NMSSM-like scenario free of the μ-b μ problem. Current cosmological constraints imply a small size for the anomaly-mediation contributions, unless some source of R-parity violation is permitted. In the latter case the allowed regions in the parameter space can be substantially larger than in the corresponding gauge-mediation scenario.

  20. Transitional lumbosacral vertebral anomaly in the dog: a radiographic study

    International Nuclear Information System (INIS)

    Morgan, J.P.

    1999-01-01

    Transitional lumbosacral vertebral anomalies have for some time been suggested as a possible cause of cauda equina syndrome (especially in the German shepherd dog [GSD]), a condition recently thought to be inherited. The frequency of this condition within a large clinical population and the radiographic features used in its detection are reported. In a group of 143 patients, the sexes were similarly represented and the GSD was greatly over represented. The anomaly is characterised by separation of the first sacral segment that was identified on the lateral view by the presence of a radiolucent disc space between what are normally the first and second sacral segments. On the ventrodorsal view, the anomaly was characterised by separation of the spinous processes between what are normally the first and second sacral segments. In the presence of the transitional segment, the nature of the sacroiliac joint at the level of the anomalous segment varies from a strong ilial attachment, with the presence of a wing-like lateral process, to a weakened ilial attachment because of the presence of a lateral process, shaped as that seen on a lumbar segment. These patterns were present unilaterally or bilaterally and result in symmetrical or asymmetrical patterns. The effect of the weakening of the sacroiliac attachment was thought to result in premature disc degeneration, which, together with spinal canal stenosis, resulted in potential compression of the overlying spinal nerves and creation of a cauda equina syndrome. The condition is thought to have clinical significance and should be selected against in breeding, especially in the GSD

  1. Absence of lattice strain anomalies at the electronic topological transition in zinc at high pressure

    International Nuclear Information System (INIS)

    Steinle-Neumann, Gerd; Stixrude, Lars; Cohen, Ronald E.

    2001-01-01

    High-pressure structural distortions of the hexagonal close-packed (hcp) element zinc have been a subject of controversy. Earlier experimental results and theory showed a large anomaly in lattice strain with compression in zinc at about 10 GPa which was explained theoretically by a change in Fermi surface topology. Later hydrostatic experiments showed no such anomaly, resulting in a discrepancy between theory and experiment. We have computed the compression and lattice strain of hcp zinc over a wide range of compressions using the linearized augmented plane-wave method paying special attention to k-point convergence. We find that the behavior of the lattice strain is strongly dependent on k-point sampling, and with large k-point sets the previously computed anomaly in lattice parameters under compression disappears, in agreement with recent experiments

  2. The 2014-2015 Warming Anomaly in the Southern California Current System: Glider Observations

    Science.gov (United States)

    Zaba, K. D.; Rudnick, D. L.

    2016-02-01

    During 2014-2015, basin-wide patterns of oceanic and atmospheric anomalies affected surface waters throughout the North Pacific Ocean. We present regional physical and biological effects of the warming, as observed by our autonomous underwater gliders in the southern California Current System (SCCS). Established in 2006, the California Glider Network provides sustained subsurface observations for monitoring the coastal effects of large-scale climate variability. Along repeat sections that extend to 350-500 km in offshore distance and 500 m in depth, Spray gliders have continuously occupied CalCOFI lines 66.7, 80, and 90 for nearly nine years. Following a sawtooth trajectory, the gliders complete each dive in approximately 3 hours and over 3 km. Measured variables include pressure, temperature, salinity, chlorophyll fluorescence, and velocity. For each of the three lines, a comprehensive climatology has been constructed from the multiyear timeseries. The ongoing surface-intensified warming anomaly, which began locally in early 2014 and persists through present, is unprecedented in the glider climatology. Reaching up to 5°C, positive temperature anomalies have been generally confined to the upper 50 m and persistent for over 20 months. The timing of the warming was in phase along each glider line but out of phase with equatorial SST anomalies, suggesting a decoupling of tropical and mid-latitude dynamics. Concurrent physical oceanographic anomalies included a depressed thermocline and high stratification. An induced biological response was apparent in the deepening of the subsurface chlorophyll fluorescence maximum. Ancillary atmospheric data from the NCEP North American Mesoscale (NAM) model indicate that a combination of surface forcing anomalies, namely high downward heat flux and weak wind stress magnitude, caused the unusual warm, downwelling conditions. With a strong El Niño event in the forecast for winter 2015-2016, our sustained glider network will

  3. Structural modeling of the Vichada impact structure from interpreted ground gravity and magnetic anomalies

    International Nuclear Information System (INIS)

    Hernandez, Orlando; Khurama, Sait; Alexander, Gretta C

    2011-01-01

    A prominent positive free-air gravity anomaly mapped over a roughly 50-km diameter basin is consistent with a mascon centered on (4 degrades 30 minutes N, 69 degrades 15 minutes W) in the Vichada Department, Colombia, South America. Ground follow up gravity and magnetic anomalies were modeled confirming the regional free air gravity anomalies. These potential field anomalies infer a hidden complex impact basin structure filled with tertiary sedimentary rocks and recent quaternary deposits. Negative Bouguer anomalies of 8 mgals to 15 mgals amplitude are associated with a concentric sedimentary basin with a varying thickness from 100 m to 500 m in the outer rings to 700 m to 1000 m at the center of the impact crater basin. Strong positive magnetic anomalies of 100 nt to 300 nt amplitude infer the presence of a local Precambrian crystalline basement that was affected by intensive faulting producing tectonic blocks dipping to the center of the structure, showing a typical domino structure of impact craters such as that of Sudbury, Ontario, Canada. Basic to intermediate mineralized veins and dikes with contrasting density and magnetic susceptibility properties could be emplaced along these faulting zones, as inferred from local gravity and magnetic highs. The geologic mapping of the area is limited by the flat topography and absence of outcrops/ geomorphologic units. Nevertheless, local normal faults along the inner ring together with radially sparse irregular blocks over flat terrains can be associated with terraced rims or collapse of the inner crater structure and eject blanket, respectively. A detailed airborne electromagnetic survey is recommended to confirm the gravity and magnetic anomalies together with a seismic program to evaluate the economic implications for energy and mineral exploration of the Vichada impact structure.

  4. The inflationary origin of the Cold Spot anomaly

    International Nuclear Information System (INIS)

    Bueno Sánchez, Juan C.

    2014-01-01

    Single-field inflation, arguably the simplest and most compelling paradigm for the origin of our Universe, is strongly supported by the recent results of the Planck satellite and the BICEP2 experiment. The results from Planck, however, also confirm the presence of a number of anomalies in the Cosmic Microwave Background (CMB), whose origin becomes problematic in single-field inflation. Among the most prominent and well-tested of these anomalies is the Cold Spot, which constitutes the only significant deviation from Gaussianity in the CMB. Planck's non-detection of primordial non-Gaussianity on smaller scales thus suggests the existence of a physical mechanism whereby significant non-Gaussianity is generated on large angular scales only. In this Letter, we address this question by developing a localized version of the inhomogeneous reheating scenario, which postulates the existence of a scalar field able to modify the decay of the inflaton on localized spatial regions only. We demonstrate that if the Cold Spot is due to an overdensity in the last scattering surface, the localization mechanism offers a feasible explanation for it, thus providing a physical mechanism for the generation of localized non-Gaussianity in the CMB. If, on the contrary, the Cold Spot is caused by a newly discovered supervoid (as recently claimed), we argue that the localization mechanism, while managing to enhance underdensities, may well shed light on the rarity of the discovered supervoid

  5. Spatially modulated instabilities of holographic gauge-gravitational anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yan [Department of Space Science, and International Research Institute of Multidisciplinary Science,Beihang University,Beijing 100191 (China); Instituto de Fisica Teorica UAM/CSIC, Universidad Autonoma de Madrid,Cantoblanco, 28049 Madrid (Spain); Pena-Benitez, Francisco [Dipartimento di Fisica, Università di Perugia, I.N.F.N. Sezione di Perugia,Via A. Pascoli, I-06123 Perugia (Italy)

    2017-05-19

    We performed a study of the perturbative instabilities in Einstein-Maxwell-Chern-Simons theory with a gravitational Chern-Simons term, which is dual to a strongly coupled field theory with both chiral and mixed gauge-gravitational anomaly. With an analysis of the fluctuations in the near horizon regime at zero temperature, we found that there might be two possible sources of instabilities. The first one corresponds to a real mass-squared which is below the BF bound of AdS{sub 2}, and it leads to the bell-curve phase diagram at finite temperature. The effect of mixed gauge-gravitational anomaly is emphasised. Another source of instability is independent of gauge Chern-Simons coupling and exists for any finite gravitational Chern-Simons coupling. There is a singular momentum close to which unstable mode appears. The possible implications of this singular momentum are discussed. Our analysis suggests that the theory with a gravitational Chern-Simons term around Reissner-Nordström black hole is unreliable unless the gravitational Chern-Simons coupling is treated as a small perturbative parameter.

  6. The inflationary origin of the Cold Spot anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Bueno Sánchez, Juan C., E-mail: juan.c.bueno@correounivalle.edu.co [Departamento de Física, Universidad del Valle, A.A. 25360, Santiago de Cali (Colombia); Centro de Investigaciones en Ciencias Básicas y Aplicadas, Universidad Antonio Nariño, Cra 3 Este # 47A-15, Bogotá D.C. 110231 (Colombia); Escuela de Física, Universidad Industrial de Santander, Ciudad Universitaria, Bucaramanga 680002 (Colombia); Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, 28040, Madrid (Spain)

    2014-12-12

    Single-field inflation, arguably the simplest and most compelling paradigm for the origin of our Universe, is strongly supported by the recent results of the Planck satellite and the BICEP2 experiment. The results from Planck, however, also confirm the presence of a number of anomalies in the Cosmic Microwave Background (CMB), whose origin becomes problematic in single-field inflation. Among the most prominent and well-tested of these anomalies is the Cold Spot, which constitutes the only significant deviation from Gaussianity in the CMB. Planck's non-detection of primordial non-Gaussianity on smaller scales thus suggests the existence of a physical mechanism whereby significant non-Gaussianity is generated on large angular scales only. In this Letter, we address this question by developing a localized version of the inhomogeneous reheating scenario, which postulates the existence of a scalar field able to modify the decay of the inflaton on localized spatial regions only. We demonstrate that if the Cold Spot is due to an overdensity in the last scattering surface, the localization mechanism offers a feasible explanation for it, thus providing a physical mechanism for the generation of localized non-Gaussianity in the CMB. If, on the contrary, the Cold Spot is caused by a newly discovered supervoid (as recently claimed), we argue that the localization mechanism, while managing to enhance underdensities, may well shed light on the rarity of the discovered supervoid.

  7. Regional seasonal warming anomalies and land-surface feedbacks

    Science.gov (United States)

    Coffel, E.; Horton, R. M.

    2017-12-01

    Significant seasonal variations in warming are projected in some regions, especially central Europe, the southeastern U.S., and central South America. Europe in particular may experience up to 2°C more warming during June, July, and August than in the annual mean, enhancing the risk of extreme summertime heat. Previous research has shown that heat waves in Europe and other regions are tied to seasonal soil moisture variations, and that in general land-surface feedbacks have a strong effect on seasonal temperature anomalies. In this study, we show that the seasonal anomalies in warming are also due in part to land-surface feedbacks. We find that in regions with amplified warming during the hot season, surface soil moisture levels generally decline and Bowen ratios increase as a result of a preferential partitioning of incoming energy into sensible vs. latent. The CMIP5 model suite shows significant variability in the strength of land-atmosphere coupling and in projections of future precipitation and soil moisture. Due to the dependence of seasonal warming on land-surface processes, these inter-model variations influence the projected summertime warming amplification and contribute to the uncertainty in projections of future extreme heat.

  8. Trisomy 19 as the sole chromosomal anomaly in hematologic neoplasms.

    Science.gov (United States)

    Johansson, B; Billström, R; Mauritzson, N; Mitelman, F

    1994-05-01

    Trisomy 19 was found as the sole chromosomal aberration in three hematologic malignancies: one chronic myelomonocytic leukemia and two cases of of immunophenotypically immature acute myeloid leukemia (AML). A compilation of previously published hematologic neoplasms with +19 as the only change reveals that this anomaly is strongly associated with myeloid malignancies; 25 of 31 cases have been myelodysplastic syndromes (MDS) or AML. Eight of the 11 MDS cases have been either refractory anemia (RA) or RA with excess of blasts, and four of the 14 AML cases have had preleukemic myelodysplastic cases phase, with the +19 accruing during the time of leukemic transformation. The AML cases have, in general, been either or early maturation arrest, i.e. undifferentiated or AML-M1/M2, or of myelomonocytic-monoblastic origin, i.e., AML-M4/M5. None of the MDS or AML cases with +19 had had a previous history of radio- or chemotherapy. We conclude that trisomy 19, as the sole anomaly, is a characteristic abnormality in de novo myeloid malignancies. No clinical features seem to characterize patients with +19 AML and MDS and the prognostic impact of the aberration remains to be elucidated.

  9. Analyzing Spatiotemporal Anomalies through Interactive Visualization

    Directory of Open Access Journals (Sweden)

    Tao Zhang

    2014-06-01

    Full Text Available As we move into the big data era, data grows not just in size, but also in complexity, containing a rich set of attributes, including location and time information, such as data from mobile devices (e.g., smart phones, natural disasters (e.g., earthquake and hurricane, epidemic spread, etc. We are motivated by the rising challenge and build a visualization tool for exploring generic spatiotemporal data, i.e., records containing time location information and numeric attribute values. Since the values often evolve over time and across geographic regions, we are particularly interested in detecting and analyzing the anomalous changes over time/space. Our analytic tool is based on geographic information system and is combined with spatiotemporal data mining algorithms, as well as various data visualization techniques, such as anomaly grids and anomaly bars superimposed on the map. We study how effective the tool may guide users to find potential anomalies through demonstrating and evaluating over publicly available spatiotemporal datasets. The tool for spatiotemporal anomaly analysis and visualization is useful in many domains, such as security investigation and monitoring, situation awareness, etc.

  10. Possible Waardenburg syndrome with gastrointestinal anomalies.

    OpenAIRE

    Nutman, J; Steinherz, R; Sivan, Y; Goodman, R M

    1986-01-01

    We describe a patient with possible Waardenburg syndrome associated with anal atresia and oesophageal atresia with tracheooesophageal fistula. Three other published cases with atretic gastrointestinal anomalies associated with the Waardenburg syndrome are reviewed. We conclude that the association between atretic lesions of the gastrointestinal tract and the Waardenburg syndrome may be a significant one.

  11. Possible Waardenburg syndrome with gastrointestinal anomalies.

    Science.gov (United States)

    Nutman, J; Steinherz, R; Sivan, Y; Goodman, R M

    1986-01-01

    We describe a patient with possible Waardenburg syndrome associated with anal atresia and oesophageal atresia with tracheooesophageal fistula. Three other published cases with atretic gastrointestinal anomalies associated with the Waardenburg syndrome are reviewed. We conclude that the association between atretic lesions of the gastrointestinal tract and the Waardenburg syndrome may be a significant one. Images PMID:3712396

  12. Congenital spine anomalies: the closed spinal dysraphisms

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, Erin Simon [University of Pennsylvania, Department of Radiology, The Children' s Hospital of Philadelphia, Perelman School of Medicine, Philadelphia, PA (United States); Rossi, Andrea [G. Gaslini Children' s Hospital, Department of Radiology, Genoa (Italy)

    2015-09-15

    The term congenital spinal anomalies encompasses a wide variety of dysmorphology that occurs during early development. Familiarity with current terminology and a practical, clinico-radiologic classification system allows the radiologist to have a more complete understanding of malformations of the spine and improves accuracy of diagnosis when these entities are encountered in practice. (orig.)

  13. Conformal anomaly actions for dilaton interactions

    Directory of Open Access Journals (Sweden)

    Rose Luigi Delle

    2014-01-01

    Full Text Available We discuss, in conformally invariant field theories such as QCD with massless fermions, a possible link between the perturbative signature of the conformal anomaly, in the form of anomaly poles of the 1-particle irreducible effective action, and its descrip- tion in terms of Wess-Zumino actions with a dilaton. The two descriptions are expected to capture the UV and IR behaviour of the conformal anomaly, in terms of fundamental and effective degrees of freedom respectively, with the dilaton effective state appearing in a nonlinear realization. As in the chiral case, conformal anomalies seem to be related to the appearance of these effective interactions in the 1PI action in all the gauge-invariant sectors of the Standard Model. We show that, as a consequence of the underlying anomalous symmetry, the infinite hierarchy of recurrence relations involving self-interactions of the dilaton is entirely determined only by the first four of them. This relation can be generalized to any even space-time dimension.

  14. An undescribed first branchial cleft anomaly.

    Science.gov (United States)

    Rockey, Jason Gabriel; John, D Gareth; Herbetko, John

    2003-06-01

    A variant of a type 2 first branchial cleft anomaly, in which accessory ossicles were found, is described. There follows a discussion of the classification of first branchial cleft abnormalities and how this particular case falls outside the standard classification. CT scanning is mentioned as the investigation that is most useful for defining these abnormalities.

  15. Thymic cyst: a fourth branchial cleft anomaly.

    Science.gov (United States)

    Nayan, Smriti; MacLean, Jonathan; Sommer, Doron

    2010-01-01

    We report a unique case of a fourth branchial cleft cyst found within the thymus of an adult patient. In the literature to date, there have been no reports of such a finding in the adult population. These anomalies can often cause recurrent acute suppurative thyroiditis or recurrent deep neck abscesses. Delay in recognizing the underlying etiology can lead to significant complications.

  16. An anomaly analysis framework for database systems

    NARCIS (Netherlands)

    Vavilis, S.; Egner, A.I.; Petkovic, M.; Zannone, N.

    2015-01-01

    Anomaly detection systems are usually employed to monitor database activities in order to detect security incidents. These systems raise an alert when anomalous activities are detected. The raised alerts have to be analyzed to timely respond to the security incidents. Their analysis, however, is

  17. An Unsupervised Deep Hyperspectral Anomaly Detector

    Directory of Open Access Journals (Sweden)

    Ning Ma

    2018-02-01

    Full Text Available Hyperspectral image (HSI based detection has attracted considerable attention recently in agriculture, environmental protection and military applications as different wavelengths of light can be advantageously used to discriminate different types of objects. Unfortunately, estimating the background distribution and the detection of interesting local objects is not straightforward, and anomaly detectors may give false alarms. In this paper, a Deep Belief Network (DBN based anomaly detector is proposed. The high-level features and reconstruction errors are learned through the network in a manner which is not affected by previous background distribution assumption. To reduce contamination by local anomalies, adaptive weights are constructed from reconstruction errors and statistical information. By using the code image which is generated during the inference of DBN and modified by adaptively updated weights, a local Euclidean distance between under test pixels and their neighboring pixels is used to determine the anomaly targets. Experimental results on synthetic and recorded HSI datasets show the performance of proposed method outperforms the classic global Reed-Xiaoli detector (RXD, local RX detector (LRXD and the-state-of-the-art Collaborative Representation detector (CRD.

  18. Seasonality of congenital anomalies in Europe

    DEFF Research Database (Denmark)

    Luteijn, Johannes Michiel; Dolk, Helen; Addor, Marie-Claude

    2014-01-01

    BACKGROUND: This study describes seasonality of congenital anomalies in Europe to provide a baseline against which to assess the impact of specific time varying exposures such as the H1N1 pandemic influenza, and to provide a comprehensive and recent picture of seasonality and its possible relatio...

  19. Genetically caused congenital anomalies of reproductive system

    Directory of Open Access Journals (Sweden)

    L. F. Kurilo

    2013-01-01

    Full Text Available Classification of congenital disorders, their frequency of occurrence in populations, and some terminology questions discussed in the review. Genetically caused congenital anomalies of reproductive system are outlined. Full information about genetic syndromes is stated in the book: Kozlova S.I., Demikova N.S. Hereditary syndromes and genetic counseling. M., 2007.

  20. Gravitational anomalies in the solar system?

    Science.gov (United States)

    Iorio, Lorenzo

    2015-02-01

    Mindful of the anomalous perihelion precession of Mercury discovered by Le Verrier in the second half of the nineteenth century and its successful explanation by Einstein with his General Theory of Relativity in the early years of the twentieth century, discrepancies among observed effects in our Solar system and their theoretical predictions on the basis of the currently accepted laws of gravitation applied to known matter-energy distributions have the potential of paving the way for remarkable advances in fundamental physics. This is particularly important now more than ever, given that most of the universe seems to be made of unknown substances dubbed Dark Matter and Dark Energy. Should this not be directly the case, Solar system's anomalies could anyhow lead to advancements in either cumulative science, as shown to us by the discovery of Neptune in the first half of the nineteenth century, and technology itself. Moreover, investigations in one of such directions can serendipitously enrich the other one as well. The current status of some alleged gravitational anomalies in the Solar system is critically reviewed. They are: (a) Possible anomalous advances of planetary perihelia. (b) Unexplained orbital residuals of a recently discovered moon of Uranus (Mab). (c) The lingering unexplained secular increase of the eccentricity of the orbit of the Moon. (d) The so-called Faint Young Sun Paradox. (e) The secular decrease of the mass parameter of the Sun. (f) The Flyby Anomaly. (g) The Pioneer Anomaly. (h) The anomalous secular increase of the astronomical unit.

  1. Congenital Duplex Gallbladder Anomaly Presenting as Gangrenous ...

    African Journals Online (AJOL)

    Valued eMachines Customer

    A 43 year old female patient, Mrs. M.S, presented with a three week history of .... they develop gangrenous calculus cholecystitis as they may simulate a liver abscess ... Congenital anomalies of the gallbladder and anatomical variations of their ...

  2. Drug safety in pregnancy - monitoring congenital anomalies

    NARCIS (Netherlands)

    Morgan, Margery; De Jong-Van Den Berg, Lolkje T. W.; Jordan, Sue

    Aim This paper outlines research into the causes of congenital anomalies, and introduces a pan-European study. The potential roles of nurses and midwives in this area are illustrated by a case report. Background Since the thalidomide disaster, use of drugs in pregnancy has been carefully monitored

  3. A Semiparametric Model for Hyperspectral Anomaly Detection

    Science.gov (United States)

    2012-01-01

    treeline ) in the presence of natural background clutter (e.g., trees, dirt roads, grasses). Each target consists of about 7 × 4 pixels, and each pixel...vehicles near the treeline in Cube 1 (Figure 1) constitutes the target set, but, since anomaly detectors are not designed to detect a particular target

  4. Alaska Terrain Corrected Free Air Anomalies (96)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This 2' x 4' gravity anomaly grid for Alaska is NOT the input data set used in development of the GEOID96 model. This gravity grid models the 1.1 million terrestrial...

  5. Conformal anomalies and the Einstein field equations

    Energy Technology Data Exchange (ETDEWEB)

    Godazgar, Hadi [Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut), Mühlenberg 1, D-14476 Potsdam (Germany); Meissner, Krzysztof A. [Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw (Poland); Nicolai, Hermann [Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut), Mühlenberg 1, D-14476 Potsdam (Germany)

    2017-04-28

    We compute corrections to the Einstein field equations which are induced by the anomalous effective actions associated to the type A conformal anomaly, both for the (non-local) Riegert action, as well as for the local action with dilaton. In all cases considered we find that these corrections can be very large.

  6. Anomalies in radiation decays of charmed mesons

    International Nuclear Information System (INIS)

    Kalinovskij, Yu.L.; Pervushin, V.N.; Sarikov, N.A.

    1986-01-01

    The amplitudes of the charmed meson decays D→0 - +0 - +γ and F→0 - +0 - +γ are calculated in the framework of the SU(4)xSU(4)-chiral Lagrangians with account for anomalies. It is shown that in this approach no E1-transition exists

  7. Psychoeducational Implications of Sex Chromosome Anomalies

    Science.gov (United States)

    Wodrich, David L.; Tarbox, Jennifer

    2008-01-01

    Numerous anomalies involving the sex chromosomes (X or Y) have been documented and their impact on development, learning, and behavior studied. This article reviews three of these disorders, Turner syndrome, Klinefelter syndrome, and Lesch-Nyhan disease. Each of these three is associated with one or more selective impairments or behavioral…

  8. Detection of cardiovascular anomalies: Hybrid systems approach

    KAUST Repository

    Ledezma, Fernando

    2012-06-06

    In this paper, we propose a hybrid interpretation of the cardiovascular system. Based on a model proposed by Simaan et al. (2009), we study the problem of detecting cardiovascular anomalies that can be caused by variations in some physiological parameters, using an observerbased approach. We present the first numerical results obtained. © 2012 IFAC.

  9. Seasonality of Congenital Anomalies in Europe

    NARCIS (Netherlands)

    Luteijn, Johannes Michiel; Dolk, Helen; Addor, Marie-Claude; Arriola, Larraitz; Barisic, Ingeborg; Bianchi, Fabrizio; Calzolari, Elisa; Draper, Elizabeth; Garne, Ester; Gatt, Miriam; Haeusler, Martin; Khoshnood, Babak; McDonnell, Bob; Nelen, Vera; O'Mahony, Mary; Mullaney, Carmel; Queisser-Luft, Annette; Rankin, Judith; Tucker, David; Verellen-Dumoulin, Christine; de Walle, Hermien; Yevtushok, Lyubov

    BackgroundThis study describes seasonality of congenital anomalies in Europe to provide a baseline against which to assess the impact of specific time varying exposures such as the H1N1 pandemic influenza, and to provide a comprehensive and recent picture of seasonality and its possible relation to

  10. Calcium isotopic anomalies in the Allende meteorite

    International Nuclear Information System (INIS)

    Lee, T.; Papanastassiou, D.A.; Wasserburg, G.J.

    1978-01-01

    We report isotopic anomalies in Ca which were found in two Ca-Al-rich inclusions of the Allende meteorite. These inclusions previously had been shown to contain special anomalies for Mg and O which were attributed to fractionation and unknown nuclear effects. The Ca data, when corrected for mass fractionation by using 40 Ca/ 44 Ca as a standard, show nonlinear isotopic effects in 48 Ca of +13.5 per mil and in 42 Ca of +1.7 per mil for one sample. The second sample shows a 48 Ca depletion of -2.9 per mil, but all other isotopes are normal. Samples with large excesses in 26 Mg show no Ca anomalies. The effects demonstrate that isotopic anomalies exist for higher-atomic-number refractory elements in solar-system materials and do not appear to be readily explainable by a simple model. The correlation of O, Mg, and Ca results on the same inclusions requires the addition and preservation in the solar system of components from idverse nucleosynthetic sources. Observed anomalous Mg and Ca compositions for coexisting mineral phases are uniform within each inclusion, and require initial isotopic homogeneity within an inclusion but the preservation of wide variations between inclusions. Assuming formation of these inclusions by condensation from a gaseous part of the solar nebula, this implies isotopic heterogeneity on a scale of 10-10 2 km within the nebula

  11. Trace anomaly and counterterms in designer gravity

    Energy Technology Data Exchange (ETDEWEB)

    Anabalón, Andrés [Departamento de Ciencias, Facultad de Artes Liberalesand Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez,Av. Padre Hurtado 750, Viña del Mar (Chile); Astefanesei, Dumitru [Instituto de Física, Pontificia Universidad Católica de Valparaíso,Casilla 4059, Valparaíso (Chile); Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut,14476 Golm (Germany); Choque, David [Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut,14476 Golm (Germany); Universidad Técnica Federico Santa María,Av. España 1680, Valparaíso (Chile); Martínez, Cristián [Centro de Estudios Científicos (CECs),Av. Arturo Prat 514, Valdivia (Chile)

    2016-03-17

    We construct concrete counterterms of the Balasubramanian-Kraus type for Einstein-scalar theories with designer gravity boundary conditions in AdS{sub 4}, so that the total action is finite on-shell and satisfy a well defined variational principle. We focus on scalar fields with the conformal mass m{sup 2}=−2l{sup −2} and show that the holographic mass matches the Hamiltonian mass for any boundary conditions. We compute the trace anomaly of the dual field theory in the generic case, as well as when there exist logarithmic branches of non-linear origin. As expected, the anomaly vanishes for the boundary conditions that are AdS invariant. When the anomaly does not vanish, the dual stress tensor describes a thermal gas with an equation of state related to the boundary conditions of the scalar field. In the case of a vanishing anomaly, we recover the dual theory of a massless thermal gas. As an application of the formalism, we consider a general family of exact hairy black hole solutions that, for some particular values of the parameters in the moduli potential, contains solutions of four-dimensional gauged N=8 supergravity and its ω-deformation. Using the AdS/CFT duality dictionary, they correspond to triple trace deformations of the dual field theory.

  12. Reducing customer minutes lost by anomaly detection?

    NARCIS (Netherlands)

    Bakker, M.; Vreeburg, J.H.G.; Rietveld, L.C.; van der Roer, M.

    2012-01-01

    An method which compares measured and predicted water demands to detect anomalies, was developed and tested on three data sets of water demand of three years in which and 25 pipe bursts were reported. The method proved to be able to detect bursts where the water loss exceeds 30% of the average water

  13. Trace anomaly and counterterms in designer gravity

    International Nuclear Information System (INIS)

    Anabalón, Andrés; Astefanesei, Dumitru; Choque, David; Martínez, Cristián

    2016-01-01

    We construct concrete counterterms of the Balasubramanian-Kraus type for Einstein-scalar theories with designer gravity boundary conditions in AdS_4, so that the total action is finite on-shell and satisfy a well defined variational principle. We focus on scalar fields with the conformal mass m"2=−2l"−"2 and show that the holographic mass matches the Hamiltonian mass for any boundary conditions. We compute the trace anomaly of the dual field theory in the generic case, as well as when there exist logarithmic branches of non-linear origin. As expected, the anomaly vanishes for the boundary conditions that are AdS invariant. When the anomaly does not vanish, the dual stress tensor describes a thermal gas with an equation of state related to the boundary conditions of the scalar field. In the case of a vanishing anomaly, we recover the dual theory of a massless thermal gas. As an application of the formalism, we consider a general family of exact hairy black hole solutions that, for some particular values of the parameters in the moduli potential, contains solutions of four-dimensional gauged N=8 supergravity and its ω-deformation. Using the AdS/CFT duality dictionary, they correspond to triple trace deformations of the dual field theory.

  14. Kohn anomaly in phonon driven superconductors

    International Nuclear Information System (INIS)

    Das, M P; Chaudhury, R

    2014-01-01

    Anomalies often occur in the physical world. Sometimes quite unexpectedly anomalies may give rise to new insight to an unrecognized phenomenon. In this paper we shall discuss about Kohn anomaly in a conventional phonon-driven superconductor by using a microscopic approach. Recently Aynajian et al.'s experiment showed a striking feature; the energy of phonon at a particular wave-vector is almost exactly equal to twice the energy of the superconducting gap. Although the phonon mechanism of superconductivity is well known for many conventional superconductors, as has been noted by Scalapino, the new experimental results reveal a genuine puzzle. In our recent work we have presented a detailed theoretical analysis with the help of microscopic calculations to unravel this mystery. We probe this aspect of phonon behaviour from the properties of electronic polarizability function in the superconducting phase of a Fermi liquid metal, leading to the appearance of a Kohn singularity. We show the crossover to the standard Kohn anomaly of the normal phase for temperatures above the transition temperature. Our analysis provides a nearly complete explanation of this new experimentally discovered phenomenon. This report is a shorter version of our recent work in JPCM.

  15. Anomaly Detection using the "Isolation Forest" algorithm

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    Anomaly detection can provide clues about an outlying minority class in your data: hackers in a set of network events, fraudsters in a set of credit card transactions, or exotic particles in a set of high-energy collisions. In this talk, we analyze a real dataset of breast tissue biopsies, with malignant results forming the minority class. The "Isolation Forest" algorithm finds anomalies by deliberately “overfitting” models that memorize each data point. Since outliers have more empty space around them, they take fewer steps to memorize. Intuitively, a house in the country can be identified simply as “that house out by the farm”, while a house in the city needs a longer description like “that house in Brooklyn, near Prospect Park, on Union Street, between the firehouse and the library, not far from the French restaurant”. We first use anomaly detection to find outliers in the biopsy data, then apply traditional predictive modeling to discover rules that separate anomalies from normal data...

  16. Anomaly manifestation of Lieb-Schultz-Mattis theorem and topological phases

    Science.gov (United States)

    Cho, Gil Young; Hsieh, Chang-Tse; Ryu, Shinsei

    2017-11-01

    The Lieb-Schultz-Mattis (LSM) theorem dictates that emergent low-energy states from a lattice model cannot be a trivial symmetric insulator if the filling per unit cell is not integral and if the lattice translation symmetry and particle number conservation are strictly imposed. In this paper, we compare the one-dimensional gapless states enforced by the LSM theorem and the boundaries of one-higher dimensional strong symmetry-protected topological (SPT) phases from the perspective of quantum anomalies. We first note that they can both be described by the same low-energy effective field theory with the same effective symmetry realizations on low-energy modes, wherein non-on-site lattice translation symmetry is encoded as if it were an internal symmetry. In spite of the identical form of the low-energy effective field theories, we show that the quantum anomalies of the theories play different roles in the two systems. In particular, we find that the chiral anomaly is equivalent to the LSM theorem, whereas there is another anomaly that is not related to the LSM theorem but is intrinsic to the SPT states. As an application, we extend the conventional LSM theorem to multiple-charge multiple-species problems and construct several exotic symmetric insulators. We also find that the (3+1)d chiral anomaly provides only the perturbative stability of the gaplessness local in the parameter space.

  17. [Clinical symptoms and signs in Kimmerle anomaly].

    Science.gov (United States)

    Split, Wojciech; Sawrasewicz-Rybak, Małgorzata

    2002-01-01

    The aim of the study was to consider Kimmerle anomaly (ponticulus posterior of the atlas) as an anatomic variant, which can cause a set of clinical symptoms and signs. A hundred and eight patients, 58 females and 50 males at the age of 18-59 years (M. 36.9 years, SD = 9.6) with radiologically verified Kimmerle anomaly were examined. A control group comprised 40 healthy subjects at the similar age range. The diagnosis of headaches was based on the criteria proposed by the IHS. A character of headaches, their localization, frequency, duration, number of days with headaches per year, circumstances associated with their onset and concomitant symptoms were evaluated. All the patients were subjected to electrophysiological studies (ENG, EEG and VEP). The results were statistically analyzed using a SPSS/PC+ computer system. It was revealed that clinical symptoms and signs in Kimmerle anomaly occurred most frequently in the third and fourth decade of life (65% of cases). These were most often tension-type headaches (50% of cases with headaches), vascular headaches (26% of cases) and neuralgia (24% of cases). Intensity of headaches was high. Headaches were accompanied by other complaints like vertigo (59% of cases) and in one third of cases--nausea. About 10% of patients also suffered from vomiting, paresthesia, dizziness, short periods of loss of consciousness. Sporadically--tinitus, drop attack, and vegetative symptoms. In cases without pain the most frequent signs were short periods of loss of consciousness, dizziness, and also nausea and dizziness. The EEG examination revealed pathology in 40% of patients with Kimmerle anomaly. The ENG examination in more than 33% of anomaly cases showed injury in the central part of vestibular system. Improper answers were reported in about 75% of the patients during the VEP examination.

  18. Non-perturbative supersymmetry anomaly in supersymmetric QCD

    International Nuclear Information System (INIS)

    Shamir, Y.

    1991-03-01

    The zero modes of the Dirac operator in an instanton and other topologically non-trivial backgrounds are unstable in a large class of massless or partially massless supersymmetric gauge theories. We show that under a generic perturbation of the scalar fields all zero modes become resonances, and discuss the ensuing breakdown of conventional perturbation theory. As a result, despite of the presence of massless fermions, the field theoretic tunneling amplitude is not suppressed. In massless supersymmetric QCD with N c ≤ N f the effective potential is found to be negative and monotonically increasing in the weak coupling regime for scalar VEVs which lie on the perturbatively flat directions. Consequently, massless supersymmetric QCD with N c ≤ N f exhibits a non-perturbative supersymmetry anomaly and exists in a strongly interacting phase which closely resembles ordinary QCD. The same conclusions apply if small masses are added to the lagrangian and the massless limit is smooth. (author). 21 refs, 5 figs

  19. Mass hierarchies from anomalies: A peek behind the Planck curtain

    International Nuclear Information System (INIS)

    Ramond, P.

    1996-01-01

    The masses of quarks and leptons suggest a strong hierarchical structure. We argue that their patterns can be reproduced through the introduction of a new Abelian symmetry. The data suggest that this symmetry is anomalous. We suggest that the cancellation of its anomalies occurs through the Green-Schwarz mechanism. An important check of this idea is that it links the Weinberg angle to a mass ration of the elementary fermions. The Green-Schwarz mechanism occurs naturally in many superstring compactifications, and produces a small parameter, which we use to determine the quark mass hierarchy. We show that hierarchy and mixings among the chiral fermions is a consequence of the Green-Schwarz mechanism. We present several models where this idea is realized. 16 refs., 2 tabs

  20. Anomalies of Nuclear Criticality, Revision 6

    International Nuclear Information System (INIS)

    Clayton, E.D.; Prichard, Andrew W.; Durst, Bonita E.; Erickson, David; Puigh, Raymond J.

    2010-01-01

    This report is revision 6 of the Anomalies of Nuclear Criticality. This report is required reading for the training of criticality professionals in many organizations both nationally and internationally. This report describes many different classes of nuclear criticality anomalies that are different than expected. An anomaly is defined as something not in keeping with expected notions of fitness and order, a departure from the regular arrangement or general rule. In reviewing the literature and experimental data on nuclear criticality and the conditions under which a fission chain reaction can be achieved, a number of anomalies have come to light. The actinide group is composed of the fourteen elements beginning with thorium, Atomic No. 90, and ending with lawrencium, Atomic No. 103. There are about 220 known actinide isotopes, most of which are believed capable of supporting neutron chain reactions. Although every element in the actinide group has at least one isotope believed capable of supporting a chain reaction, from a practical point of view regarding the time for chemical processing, only those nuclides with half-lives more than several weeks are of obvious concern in criticality safety. Forty-six of the nuclides are known to have half-lives greater than six weeks. The selection of six weeks is somewhat arbitrary. There may well be shorter-lived nuclides of concern in criticality safety. These 46 nuclides are identified in Figure 44. Of the 46 nuclides, 4 are known and 37 are believed to be capable of supporting chain reactions, and 5 are known or believed to not support a chain reaction. Figure 44 was constructed in the format used for the Chart of the Nuclides.(1) Figure 44 also shows the distinction between fissile and fissible nuclides. The actinides derive their name from actinium (Atomic No. 89) because they tend to maintain an actinium-like electron structure as the fourteen inner electrons are added to the 5f electron shell. Actually, electrons do

  1. Amalgamation of Anomaly-Detection Indices for Enhanced Process Monitoring

    KAUST Repository

    Harrou, Fouzi; Sun, Ying; Khadraoui, Sofiane

    2016-01-01

    Accurate and effective anomaly detection and diagnosis of modern industrial systems are crucial for ensuring reliability and safety and for maintaining desired product quality. Anomaly detection based on principal component analysis (PCA) has been

  2. First branchial complex anomalies: report of 3 cases

    International Nuclear Information System (INIS)

    Goten, A. van der; Hermans, R.; Hover, P. van; Crevits, I.; Baert, A.L.

    1997-01-01

    Three cases of first branchial cleft anomalies are presented. The embryology and pathology of first branchial complex anomalies, their imaging characteristics and differential diagnosis are discussed. (orig.). With 3 figs

  3. First branchial complex anomalies: report of 3 cases

    Energy Technology Data Exchange (ETDEWEB)

    Goten, A. van der [Department of Radiology, University Hospitals, Catholic University of Leuven, Leuven (Belgium); Hermans, R. [Department of Radiology, University Hospitals, Catholic University of Leuven, Leuven (Belgium); Hover, P. van [Department of Radiology, University Hospitals, Catholic University of Leuven, Leuven (Belgium); Crevits, I. [Department of Radiology, University Hospitals, Catholic University of Leuven, Leuven (Belgium); Baert, A.L. [Department of Radiology, University Hospitals, Catholic University of Leuven, Leuven (Belgium)

    1997-02-01

    Three cases of first branchial cleft anomalies are presented. The embryology and pathology of first branchial complex anomalies, their imaging characteristics and differential diagnosis are discussed. (orig.). With 3 figs.

  4. A Qualitative Interpretation of Residual Magnetic Anomaly using ...

    African Journals Online (AJOL)

    A Qualitative Interpretation of Residual Magnetic Anomaly using Ground ... The magnetic data was collected using a G816 proton precision magnetometer. ... Analysis of residual anomaly graph reveals the existence of some structural features ...

  5. Path Integrals and Anomalies in Curved Space

    International Nuclear Information System (INIS)

    Louko, Jorma

    2007-01-01

    Bastianelli and van Nieuwenhuizen's monograph 'Path Integrals and Anomalies in Curved Space' collects in one volume the results of the authors' 15-year research programme on anomalies that arise in Feynman diagrams of quantum field theories on curved manifolds. The programme was spurred by the path-integral techniques introduced in Alvarez-Gaume and Witten's renowned 1983 paper on gravitational anomalies which, together with the anomaly cancellation paper by Green and Schwarz, led to the string theory explosion of the 1980s. The authors have produced a tour de force, giving a comprehensive and pedagogical exposition of material that is central to current research. The first part of the book develops from scratch a formalism for defining and evaluating quantum mechanical path integrals in nonlinear sigma models, using time slicing regularization, mode regularization and dimensional regularization. The second part applies this formalism to quantum fields of spin 0, 1/2, 1 and 3/2 and to self-dual antisymmetric tensor fields. The book concludes with a discussion of gravitational anomalies in 10-dimensional supergravities, for both classical and exceptional gauge groups. The target audience is researchers and graduate students in curved spacetime quantum field theory and string theory, and the aims, style and pedagogical level have been chosen with this audience in mind. Path integrals are treated as calculational tools, and the notation and terminology are throughout tailored to calculational convenience, rather than to mathematical rigour. The style is closer to that of an exceedingly thorough and self-contained review article than to that of a textbook. As the authors mention, the first part of the book can be used as an introduction to path integrals in quantum mechanics, although in a classroom setting perhaps more likely as supplementary reading than a primary class text. Readers outside the core audience, including this reviewer, will gain from the book a

  6. Global anomalies in chiral gauge theories on the lattice

    International Nuclear Information System (INIS)

    Baer, O.; Campos, I.

    2000-01-01

    We discuss the issue of global anomalies in chiral gauge theories on the lattice. In Luescher's approach, these obstructions make it impossible to define consistently a fermionic measure for the path integral. We show that an SU(2) theory has such a global anomaly if the Weyl fermion is in the fundamental representation. The anomaly in higher representations is also discussed. We finally show that this obstruction is the lattice analogue of the SU(2) anomaly first discovered by Witten. (orig.)

  7. Distribution of female genital tract anomalies in two classifications.

    Science.gov (United States)

    Heinonen, Pentti K

    2016-11-01

    This study assessed the distribution of Müllerian duct anomalies in two verified classifications of female genital tract malformations, and the presence of associated renal defects. 621 women with confirmed female genital tract anomalies were retrospectively grouped under the European (ESHRE/ESGE) and the American (AFS) classification. The diagnosis of uterine malformation was based on findings in hysterosalpingography, two-dimensional ultrasonography, endoscopies, laparotomy, cesarean section and magnetic resonance imaging in 97.3% of cases. Renal status was determined in 378 patients, including 5 with normal uterus and vagina. The European classification covered all 621 women studied. Uterine anomalies without cervical or vaginal anomaly were found in 302 (48.6%) patients. Uterine anomaly was associated with vaginal anomaly in 45.2%, and vaginal anomaly alone was found in 26 (4.2%) cases. Septate uterus was the most common (49.1%) of all genital tract anomalies, followed by bicorporeal uteri (18.2%). The American classification covered 590 (95%) out of the 621 women with genital tract anomalies. The American system did not take into account vaginal anomalies in 170 (34.7%) and cervical anomalies in 174 (35.5%) out of 490 cases with uterine malformations. Renal abnormalities were found in 71 (18.8%) out of 378 women, unilateral renal agenesis being the most common defect (12.2%), also found in 4 women without Müllerian duct anomaly. The European classification sufficiently covered uterine and vaginal abnormalities. The distribution of the main uterine anomalies was equal in both classifications. The American system missed cervical and vaginal anomalies associated with uterine anomalies. Evaluation of renal system is recommended for all patients with genital tract anomalies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Electric propulsion reliability: Statistical analysis of on-orbit anomalies and comparative analysis of electric versus chemical propulsion failure rates

    Science.gov (United States)

    Saleh, Joseph Homer; Geng, Fan; Ku, Michelle; Walker, Mitchell L. R.

    2017-10-01

    With a few hundred spacecraft launched to date with electric propulsion (EP), it is possible to conduct an epidemiological study of EP's on orbit reliability. The first objective of the present work was to undertake such a study and analyze EP's track record of on orbit anomalies and failures by different covariates. The second objective was to provide a comparative analysis of EP's failure rates with those of chemical propulsion. Satellite operators, manufacturers, and insurers will make reliability- and risk-informed decisions regarding the adoption and promotion of EP on board spacecraft. This work provides evidence-based support for such decisions. After a thorough data collection, 162 EP-equipped satellites launched between January 1997 and December 2015 were included in our dataset for analysis. Several statistical analyses were conducted, at the aggregate level and then with the data stratified by severity of the anomaly, by orbit type, and by EP technology. Mean Time To Anomaly (MTTA) and the distribution of the time to (minor/major) anomaly were investigated, as well as anomaly rates. The important findings in this work include the following: (1) Post-2005, EP's reliability has outperformed that of chemical propulsion; (2) Hall thrusters have robustly outperformed chemical propulsion, and they maintain a small but shrinking reliability advantage over gridded ion engines. Other results were also provided, for example the differentials in MTTA of minor and major anomalies for gridded ion engines and Hall thrusters. It was shown that: (3) Hall thrusters exhibit minor anomalies very early on orbit, which might be indicative of infant anomalies, and thus would benefit from better ground testing and acceptance procedures; (4) Strong evidence exists that EP anomalies (onset and likelihood) and orbit type are dependent, a dependence likely mediated by either the space environment or differences in thrusters duty cycles; (5) Gridded ion thrusters exhibit both

  9. Convection anomalies associated with warm eddy at the coastal area

    Science.gov (United States)

    Shi, R.; Wang, D.

    2017-12-01

    A possible correlation between a warm eddy and thunderstorms and convective precipitations are investigated at the coastal area in the northwestern South China Sea. Compared to the climatological mean in August from 2006 to 2013, an extreme enhancement of thunderstorm activities and precipitation rate are identified at the southern offshore area of Hainan island in August 2010 when a strong and long-live warm eddy was observed near the coastline at the same time. The 3 hourly satellite data (TRMM) indicate that the nocturnal convections is strong offshore and that could be responsible for the extreme positive anomalies of thunderstorms and rainfall in August 2010. The TRMM data also show a small reduction of thunderstorm activities and rainfall on the island in the afternoon. Meanwhile, the Weather Research and Forecasting (WRF) model was applied to simulate the change of rainfall in August 2010. The WRF simulation of rainfall rate is comparable with the observation results while there is some difference in the spatial distribution. The WRF simulation successfully captured the strong offshore rainfall and the diurnal variation of rainfall in August 2010. The WRF simulation indicated that the different convergence induced by sea/land breeze could be one essential reason for the adjustment of thunderstorms and rainfall in 2010. The substantial connection between sea/land breeze and upper layer heat content modified by the warm eddy is still on ongoing and will be reported in the future work.

  10. Axial anomaly at finite temperature and finite density

    International Nuclear Information System (INIS)

    Qian Zhixin; Su Rukeng; Yu, P.K.N.

    1994-01-01

    The U(1) axial anomaly in a hot fermion medium is investigated by using the real time Green's function method. After calculating the lowest order triangle diagrams, we find that finite temperature as well as finite fermion density does not affect the axial anomaly. The higher order corrections for the axial anomaly are discussed. (orig.)

  11. The Fourth Branchial Complex Anomaly: A Rare Clinical Entity

    OpenAIRE

    Patel, Alpen B.; Hinni, Michael L.

    2011-01-01

    Fourth branchial pouch anomalies are rare congenital disorders of the neck and are a consequence of abnormal development of the branchial apparatus during embryogenesis. Failure to appropriately recognize these anomalies may result in misdiagnosis, insufficient treatment, and continued recurrence. Here, we present an unique presentation of two cases, describe their diagnosis, clinical course, and management, and review the literature regarding these interesting anomalies.

  12. The fourth branchial complex anomaly: a rare clinical entity.

    Science.gov (United States)

    Patel, Alpen B; Hinni, Michael L

    2011-01-01

    Fourth branchial pouch anomalies are rare congenital disorders of the neck and are a consequence of abnormal development of the branchial apparatus during embryogenesis. Failure to appropriately recognize these anomalies may result in misdiagnosis, insufficient treatment, and continued recurrence. Here, we present an unique presentation of two cases, describe their diagnosis, clinical course, and management, and review the literature regarding these interesting anomalies.

  13. Spectrum of congenital anomalies in pregnancies with pregestational diabetes

    DEFF Research Database (Denmark)

    Garne, Ester; Loane, Maria; Dolk, Helen

    2012-01-01

    Maternal pregestational diabetes is a well-known risk factor for congenital anomalies. This study analyses the spectrum of congenital anomalies associated with maternal diabetes using data from a large European database for the population-based surveillance of congenital anomalies....

  14. Spectrum of congenital anomalies in pregnancies with pregestational diabetes

    NARCIS (Netherlands)

    Garne, Ester; Loane, Maria; Dolk, Helen; Barisic, Ingeborg; Addor, Marie-Claude; Arriola, Larraitz; Bakker, Marian; Calzolari, Elisa; Dias, Carlos Matias; Doray, Berenice; Gatt, Miriam; Melve, Kari Klyungsoyr; Nelen, Vera; O'Mahony, Mary; Pierini, Anna; Randrianaivo-Ranjatoelina, Hanitra; Rankin, Judith; Rissmann, Anke; Tucker, David; Verellun-Dumoulin, Christine; Wiesel, Awi

    BACKGROUND Maternal pregestational diabetes is a well-known risk factor for congenital anomalies. This study analyses the spectrum of congenital anomalies associated with maternal diabetes using data from a large European database for the population-based surveillance of congenital anomalies.

  15. Morning glory disc anomaly: A case report | Saraswat | Nigerian ...

    African Journals Online (AJOL)

    Morning glory disc anomaly: A case report. Neeraj K. Saraswat, Ravi Ranjan, Dipendra Shukla, Sushil Ojha. Abstract. A rare case of congenital anomaly of the optic disc is presented to draw attention to the occurrence of this anomaly in rural India. The typical case presented with excavated, enlarged colobomatous optic ...

  16. Interstellar depletion anomalies and ionization potentials

    International Nuclear Information System (INIS)

    Tabak, R.G.

    1979-01-01

    Satellite observations indicate that (1) most elements are depleted from the gas phase when compared to cosmic abundances, (2) some elements are several orders of magnitude more depleted than others, and (3) these depletions vary from cloud to cloud. Since the most likely possibility is that the 'missing' atoms are locked into grains, depletions occur either by accretion onto core particles in interstellar clouds or earlier, during the period of primary grain formation. If the latter mechanism is dominant, then the most important depletion parameter is the condensation temperature of the elements and their various compounds. However, this alone is not sufficient to explain all the observed anomalies. It is shown that electrostatic effects - under a wide variety of conditions- can enormously enhance the capture cross-section of the grain. It is suggested that this mechanism can also account for such anomalies as the apparent 'overabundance' of the alkali metals in the gas phase. (orig.)

  17. Network Anomaly Detection Based on Wavelet Analysis

    Directory of Open Access Journals (Sweden)

    Ali A. Ghorbani

    2008-11-01

    Full Text Available Signal processing techniques have been applied recently for analyzing and detecting network anomalies due to their potential to find novel or unknown intrusions. In this paper, we propose a new network signal modelling technique for detecting network anomalies, combining the wavelet approximation and system identification theory. In order to characterize network traffic behaviors, we present fifteen features and use them as the input signals in our system. We then evaluate our approach with the 1999 DARPA intrusion detection dataset and conduct a comprehensive analysis of the intrusions in the dataset. Evaluation results show that the approach achieves high-detection rates in terms of both attack instances and attack types. Furthermore, we conduct a full day's evaluation in a real large-scale WiFi ISP network where five attack types are successfully detected from over 30 millions flows.

  18. Topology of Fermi surfaces and anomaly inflows

    Energy Technology Data Exchange (ETDEWEB)

    Adem, Alejandro; Camarena, Omar Antolín [Department of Mathematics, University of British Columbia,1984 Mathematics Road, Vancouver, V6T 1Z2 (Canada); Semenoff, Gordon W. [Department of Physics and Astronomy, University of British Columbia,6224 Agricultural Road, Vancouver, V6T 1Z1 (Canada); Sheinbaum, Daniel [Department of Mathematics, University of British Columbia,1984 Mathematics Road, Vancouver, V6T 1Z2 (Canada)

    2016-11-14

    We derive a rigorous classification of topologically stable Fermi surfaces of non-interacting, discrete translation-invariant systems from electronic band theory, adiabatic evolution and their topological interpretations. For systems on an infinite crystal it is shown that there can only be topologically unstable Fermi surfaces. For systems on a half-space and with a gapped bulk, our derivation naturally yields a K-theory classification. Given the d−1-dimensional surface Brillouin zone X{sub s} of a d-dimensional half-space, our result implies that different classes of globally stable Fermi surfaces belong in K{sup −1}(X{sub s}) for systems with only discrete translation-invariance. This result has a chiral anomaly inflow interpretation, as it reduces to the spectral flow for d=2. Through equivariant homotopy methods we extend these results for symmetry classes AI, AII, C and D and discuss their corresponding anomaly inflow interpretation.

  19. Helical CT of congenital ossicular anomalies

    International Nuclear Information System (INIS)

    Osada, Hisato; Machida, Kikuo; Honda, Norinari

    2001-01-01

    Since January 1996 to December 2000, 26 cases of congenital ossicular anomaly could be diagnosed with helical CT. All cases were unilateral. In 8 patients with malformation of the external ear, CT showed malleoincudal fixation (n=5), malleoincudal fixation and deformed incuts long process (n=1), deformed incus long process (n=1), and partial fusion of malleus neck and incus long process (n=1). In 18 patients with normal external ear, CT showed defect of the incus long process (n=5), defect of both the incus long process and stapes superstructure (n=8, 2 patients with congenital cholesteatoma, 1 with hypoplastic oval window), defect of the stapes superstructure (n=2, 1 patient with oval window absence), defect of the malleus manubrium (n=1), ossification of the stampede's tendon (n=1), and monopod stapes (n=1). Helical CT can evaluate the auditory ossicular chain in detail and is useful for diagnosing congenital ossicular anomaly. (author)

  20. Do retractile testes have anatomical anomalies?

    Science.gov (United States)

    Anderson, Kleber M.; Costa, Suelen F.; Sampaio, Francisco J.B.; Favorito, Luciano A.

    2016-01-01

    ABSTRACT Objectives: To assess the incidence of anatomical anomalies in patients with retractile testis. Materials and Methods: We studied prospectively 20 patients (28 testes) with truly retractile testis and compared them with 25 human fetuses (50 testes) with testis in scrotal position. We analyzed the relations among the testis, epididymis and patency of the processus vaginalis (PV). To analyze the relations between the testis and epididymis, we used a previous classification according to epididymis attachment to the testis and the presence of epididymis atresia. To analyze the structure of the PV, we considered two situations: obliteration of the PV and patency of the PV. We used the Chi-square test for contingency analysis of the populations under study (p patent processus vaginalis and epididymal anomalies. PMID:27564294

  1. Holographic models and the QCD trace anomaly

    International Nuclear Information System (INIS)

    Goity, Jose L.; Trinchero, Roberto C.

    2012-01-01

    Five dimensional dilaton models are considered as possible holographic duals of the pure gauge QCD vacuum. In the framework of these models, the QCD trace anomaly equation is considered. Each quantity appearing in that equation is computed by holographic means. Two exact solutions for different dilaton potentials corresponding to perturbative and non-perturbative β-functions are studied. It is shown that in the perturbative case, where the β-function is the QCD one at leading order, the resulting space is not asymptotically AdS. In the non-perturbative case, the model considered presents confinement of static quarks and leads to a non-vanishing gluon condensate, although it does not correspond to an asymptotically free theory. In both cases analyses based on the trace anomaly and on Wilson loops are carried out.

  2. Anomaly detection using magnetic flux leakage technology

    Energy Technology Data Exchange (ETDEWEB)

    Rempel, Raymond G. [BJ Pipeline Inspection Services, Alberta (Canada)

    2005-07-01

    There are many aspects to properly assessing the integrity of a pipeline. In-line-Inspection (ILI) tools, in particular those that employ the advanced use of Magnetic Flux Leakage (MFL) technology, provide a valuable means of achieving required up-to-date knowledge of a pipeline. More prevalent use of High Resolution MFL In-Line-Inspection tools is growing the knowledge base that leads to more reliable and accurate identification of anomalies in a pipeline, thus, minimizing the need for expensive verification excavations. Accurate assessment of pipeline anomalies can improve the decision making process within an Integrity Management Program and excavation programs can then focus on required repairs instead of calibration or exploratory digs. Utilizing the information from an MFL ILI inspection is not only cost effective but, as well, can also prove to be an extremely valuable building block of a Pipeline Integrity Management Program. (author)

  3. MR imaging evaluation of congenital spine anomalies

    International Nuclear Information System (INIS)

    Bury, E.A.; Zimmerman, R.A.; Grossman, R.I.; Goldberg, H.I.; Bilaniuk, L.T.; Hackney, D.B.

    1987-01-01

    Over a 2-year period, 135 patients between the ages of 1 week and 18 years were examined with MR imaging for possible congenital anomalies of the spine and spinal cord. Tethered cords with various other associated pathologies such as lipomas and myelomeningoceles were found in 36 patients. The remaining abnormal examinations consisted of syrinxes, Chiari malformations, diastematomyelia, and conus masses. In 55 patients the studies were interpreted as normal. Of these, three were subsequently shown by surgery of myelography to be abnormal. The first had a thickened filum with a small epidermoid, the second a thickened filum, and the third, with only sagittal images, a diastematomyelia. Children presenting with symptoms highly suspicious for congenital abnormalities but with a normal MR study in multiple planes may still require further evaluation with myelography. Multiplanar MR examination in most instances will be a sufficient evaluation for congenital anomalies

  4. Calendar anomalies in the Russian stock market

    Directory of Open Access Journals (Sweden)

    Guglielmo Maria Caporale

    2017-03-01

    Full Text Available This research note investigates whether or not calendar anomalies (such as the January, day-of-the-week and turn-of-the-month effects characterize the Russian stock market, which could be interpreted as evidence against market efficiency. Specifically, OLS, GARCH, EGARCH and TGARCH models are estimated using daily data for the MICEX market index over the period Sept. 1997–Apr. 2016. The empirical results show the importance of taking into account transactions costs (proxied by the bid-ask spreads: once these are incorporated into the analysis, calendar anomalies disappear, and therefore, there is no evidence of exploitable profit opportunities based on them that would be inconsistent with market efficiency.

  5. System and method for anomaly detection

    Science.gov (United States)

    Scherrer, Chad

    2010-06-15

    A system and method for detecting one or more anomalies in a plurality of observations is provided. In one illustrative embodiment, the observations are real-time network observations collected from a stream of network traffic. The method includes performing a discrete decomposition of the observations, and introducing derived variables to increase storage and query efficiencies. A mathematical model, such as a conditional independence model, is then generated from the formatted data. The formatted data is also used to construct frequency tables which maintain an accurate count of specific variable occurrence as indicated by the model generation process. The formatted data is then applied to the mathematical model to generate scored data. The scored data is then analyzed to detect anomalies.

  6. Diffeomorphism cohomology and gravitational anomalies: Pt. 2

    International Nuclear Information System (INIS)

    Bandelloni, G.

    1985-01-01

    Using the spectral sequencies technique, it is studied the local polynomial cohomology space of the operator S deltasub(GAMMAsub(c1))sup(L) - Csup(lambda)(x)deltasub(lambda) -deltasub(lambda)Csup(lambda)(x), which is isomorphic to the local functional cohomology of the operator deltasub(GAMMAsub(c1))sup(L) which induces general co-ordinate transformations in four-dimensional space-time. In the Faddeev-Popov (PHI II) charge-one sector, it is found that all the anomalies have the form Δ(x) deltasub(lambda)Csup(lambda)(x)Δ-circumflex(x), where Csup(lambda)(x) is the ghost field, and Δ-circumflex(x) is a PHI II charge-zero anomaly

  7. Fetal Kidney Anomalies: Next Generation Sequencing

    DEFF Research Database (Denmark)

    Rasmussen, Maria; Sunde, Lone; Nielsen, Marlene Louise

    Aim and Introduction Identification of abnormal kidneys in the fetus may lead to termination of the pregnancy and raises questions about the underlying cause and recurrence risk in future pregnancies. In this study, we investigate the effectiveness of targeted next generation sequencing in fetuses...... with prenatally detected kidney anomalies in order to uncover genetic explanations and assess recurrence risk. Also, we aim to study the relation between genetic findings and post mortem kidney histology. Methods The study comprises fetuses diagnosed prenatally with bilateral kidney anomalies that have undergone...... postmortem examination. The approximately 110 genes included in the targeted panel were chosen on the basis of their potential involvement in embryonic kidney development, cystic kidney disease, or the renin-angiotensin system. DNA was extracted from fetal tissue samples or cultured chorion villus cells...

  8. Network Anomaly Detection Based on Wavelet Analysis

    Science.gov (United States)

    Lu, Wei; Ghorbani, Ali A.

    2008-12-01

    Signal processing techniques have been applied recently for analyzing and detecting network anomalies due to their potential to find novel or unknown intrusions. In this paper, we propose a new network signal modelling technique for detecting network anomalies, combining the wavelet approximation and system identification theory. In order to characterize network traffic behaviors, we present fifteen features and use them as the input signals in our system. We then evaluate our approach with the 1999 DARPA intrusion detection dataset and conduct a comprehensive analysis of the intrusions in the dataset. Evaluation results show that the approach achieves high-detection rates in terms of both attack instances and attack types. Furthermore, we conduct a full day's evaluation in a real large-scale WiFi ISP network where five attack types are successfully detected from over 30 millions flows.

  9. Soft phonon anomalies in relaxor ferroelectrics

    International Nuclear Information System (INIS)

    Shirane, Gen; Gehring, Peter M.

    2001-01-01

    A review is given of the phonon anomalies, which have been termed waterfalls', that were recently discovered through a series of neutron inelastic scattering measurements on the lead-oxide relaxor systems PZN-xPT, PMN, and PZN. We discuss a simple coupled-mode model that has been used successfully to describe the basic features of the waterfall, and which relates this unusual feature to the presence of polar micro-regions. (author)

  10. Soft phonon anomalies in relaxor ferroelectrics

    Energy Technology Data Exchange (ETDEWEB)

    Shirane, Gen [Department of Physics, Brookhaven National Laboratory, Upton, New York (United States); Gehring, Peter M. [NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland (United States)

    2001-03-01

    A review is given of the phonon anomalies, which have been termed waterfalls', that were recently discovered through a series of neutron inelastic scattering measurements on the lead-oxide relaxor systems PZN-xPT, PMN, and PZN. We discuss a simple coupled-mode model that has been used successfully to describe the basic features of the waterfall, and which relates this unusual feature to the presence of polar micro-regions. (author)

  11. TERATOGENIC EFFECTS OF SILVER NANOPARTICLES: GROSS ANOMALIES

    OpenAIRE

    Jyoti Prakash; Rajniti; Deepika; Royana

    2015-01-01

    BACK GROUND: Prenatal exposure of AgNPs can induces devastative and detrimental effect in the organogenesis period of the developing embryos and foetuses. Organogenesis period is highly condemnatory and persuadable. Any injury to embryo during this period leads to dysmorphogenesis or even death AIM: The present study means to evaluate the gross anomalies on developing f o etus subsequent to silver nanoparticle ingestion during the gestational period. ...

  12. Anomaly extraction from the path integral

    International Nuclear Information System (INIS)

    Christos, G.A.

    1983-01-01

    Fujikawa's recently proposed derivation of the anomaly from the path integral is examined. It is attempted to give a better understanding of his work. In particular, evasions of his result are discussed; for example it is shown how chiral U(1) axial invariance can be maintained by employing a gauge variant regularization prescription. A brief connection with the point-splitting method is also made. (orig.)

  13. Mullerian Ducts Anomalies: A Simple View

    International Nuclear Information System (INIS)

    Diaz Diaz, Nelson Enrique; Riano Montanez, Yeyson Fabian; Baron Criollo, Jose alexander

    2008-01-01

    Mullerian ducts anomalies are a major cause of infertility in women of reproductive age. They have multifactorial etiology. The following article reviews the classification of the American Fertility Society, the most widely accepted at present to describe this set of pathologies. Also a schematic review of the embryology is done and are shown cases of MRI, modality of choice by image to characterize the findings in the majority of presentation forms of these entities

  14. Scaling anomalies in Kaluza-Klein theory

    International Nuclear Information System (INIS)

    Delbourgo, R.; Thompson, G.; Weber, R.O.

    1987-01-01

    The effect of Pauli interactions on the scaling anomaly is to add F/sup 4/, (∂F)/sup 2/ and m/sup 2/F/sup 2/ terms to the trace of the stress-tensor at one loop level, such terms being connected with renormalization. However, when the sum over all modes is taken, these extra contributions vanish upon zeta-function regularisation

  15. A Critique of Size-Related Anomalies.

    OpenAIRE

    Berk, Jonathan B

    1995-01-01

    This article argues that the size-related regularities in asset prices should not be regarded as anomalies. Indeed, the opposite result is demonstrated. Namely, a truly anomalous regularity would be if an inverse relation between size and return was not observed. We show theoretically (1) that the size-related regularities should be observed in the economy and (2) why size will in general explain the part of the cross-section of expected returns left unexplained by an incorrectly specified as...

  16. Chiral anomaly, bosonization and fractional charge

    International Nuclear Information System (INIS)

    Mignaco, J.A.; Rego Monteiro, M.A. do.

    1984-01-01

    A method to evaluate the Jacobian of chiral rotations, regulating determinants through the proper time method and using Seeley's asymptotic expansion is presented. With this method the chiral anomaly ofr ν=4,6 dimensions is computed easily, bosonization of some massless two-dimensional models is discussed and the problem of charge fractionization is handled. Besides, the general validity of Fujikawa's approach to regulate the Jacobian of chiral rotations with non-hermitean operators is commented. (Author) [pt

  17. Instantons and the trace anomaly condition

    International Nuclear Information System (INIS)

    Dowrick, N.; McDougall, N.A.

    1988-01-01

    In the past, it has been claimed that instanton dynamics evaluated using the dilute-gas-approximation with a cut-off do not satisfy the trace anomaly condition, and that inter-instanton interactions were required to correct this. However, they show that any model for instanton dynamics automatically satisfies the trace anomlay condition provided no dimensionful parameter other than the QCD scale Λ is introduced during the calculation, and they explain the origin of the previous (incorrect) conclusion

  18. Chiral anomaly, bosonization, and fractional charge

    International Nuclear Information System (INIS)

    Mignaco, J.A.; Monteiro, M.A.R.

    1985-01-01

    We present a method to evaluate the Jacobian of chiral rotations, regulating determinants through the proper-time method and using Seeley's asymptotic expansion. With this method we compute easily the chiral anomaly for ν = 4,6 dimensions, discuss bosonization of some massless two-dimensional models, and handle the problem of charge fractionization. In addition, we comment on the general validity of Fujikawa's approach to regulate the Jacobian of chiral rotations with non-Hermitian operators

  19. Fusion and normalization to enhance anomaly detection

    Science.gov (United States)

    Mayer, R.; Atkinson, G.; Antoniades, J.; Baumback, M.; Chester, D.; Edwards, J.; Goldstein, A.; Haas, D.; Henderson, S.; Liu, L.

    2009-05-01

    This study examines normalizing the imagery and the optimization metrics to enhance anomaly and change detection, respectively. The RX algorithm, the standard anomaly detector for hyperspectral imagery, more successfully extracts bright rather than dark man-made objects when applied to visible hyperspectral imagery. However, normalizing the imagery prior to applying the anomaly detector can help detect some of the problematic dark objects, but can also miss some bright objects. This study jointly fuses images of RX applied to normalized and unnormalized imagery and has a single decision surface. The technique was tested using imagery of commercial vehicles in urban environment gathered by a hyperspectral visible/near IR sensor mounted in an airborne platform. Combining detections first requires converting the detector output to a target probability. The observed anomaly detections were fitted with a linear combination of chi square distributions and these weights were used to help compute the target probability. Receiver Operator Characteristic (ROC) quantitatively assessed the target detection performance. The target detection performance is highly variable depending on the relative number of candidate bright and dark targets and false alarms and controlled in this study by using vegetation and street line masks. The joint Boolean OR and AND operations also generate variable performance depending on the scene. The joint SUM operation provides a reasonable compromise between OR and AND operations and has good target detection performance. In addition, new transforms based on normalizing correlation coefficient and least squares generate new transforms related to canonical correlation analysis (CCA) and a normalized image regression (NIR). Transforms based on CCA and NIR performed better than the standard approaches. Only RX detection of the unnormalized of the difference imagery in change detection provides adequate change detection performance.

  20. Standard Model Effective Potential from Trace Anomalies

    Directory of Open Access Journals (Sweden)

    Renata Jora

    2018-01-01

    Full Text Available By analogy with the low energy QCD effective linear sigma model, we construct a standard model effective potential based entirely on the requirement that the tree level and quantum level trace anomalies must be satisfied. We discuss a particular realization of this potential in connection with the Higgs boson mass and Higgs boson effective couplings to two photons and two gluons. We find that this kind of potential may describe well the known phenomenology of the Higgs boson.

  1. Anomaly equations and the persistent mass condition

    International Nuclear Information System (INIS)

    Cohen, E.; Frishman, Y.

    1982-01-01

    Vector SU(Nsub(c)) gauge theories with nsub(f) flavors in the fundamental representation are considered. We prove that if the persistent mass condition is assumed, the two anomaly equations are identical and flavor independent for nsub(f) >= 3. Integer solutions exist only for nsub(f) = 2. The necessity of a separate discussion for 2 <= nsub(f) <= Nsub(c) is explained. (orig.)

  2. Dental twinning anomalies: the nomenclature enigma.

    Science.gov (United States)

    Killian, C M; Croll, T P

    1990-07-01

    Dental twinning results from abnormal events in the embryologic development of teeth. This paper describes the impossibility of assigning precise diagnostic terms, such as germination, fusion, macrodontia, and concrescence, to dental twinning anomalies because the entire course of odontogenesis cannot be witnessed. Traditional nomenclature is reviewed and seven cases that exemplify the principle are presented. Modification of nomenclature to describe dental twinning defects is suggested.

  3. Routine screening for fetal anomalies: expectations.

    Science.gov (United States)

    Goldberg, James D

    2004-03-01

    Ultrasound has become a routine part of prenatal care. Despite this, the sensitivity and specificity of the procedure is unclear to many patients and healthcare providers. In a small study from Canada, 54.9% of women reported that they had received no information about ultrasound before their examination. In addition, 37.2% of women indicated that they were unaware of any fetal problems that ultrasound could not detect. Most centers that perform ultrasound do not have their own statistics regarding sensitivity and specificity; it is necessary to rely on large collaborative studies. Unfortunately, wide variations exist in these studies with detection rates for fetal anomalies between 13.3% and 82.4%. The Eurofetus study is the largest prospective study performed to date and because of the time and expense involved in this type of study, a similar study is not likely to be repeated. The overall fetal detection rate for anomalous fetuses was 64.1%. It is important to note that in this study, ultrasounds were performed in tertiary centers with significant experience in detecting fetal malformations. The RADIUS study also demonstrated a significantly improved detection rate of anomalies before 24 weeks in tertiary versus community centers (35% versus 13%). Two concepts seem to emerge from reviewing these data. First, patients must be made aware of the limitations of ultrasound in detecting fetal anomalies. This information is critical to allow them to make informed decisions whether to undergo ultrasound examination and to prepare them for potential outcomes.Second, to achieve the detection rates reported in the Eurofetus study, ultrasound examination must be performed in centers that have extensive experience in the detection of fetal anomalies.

  4. Power coefficient anomaly in Joyo, (2)

    International Nuclear Information System (INIS)

    Ishikawa, Makoto; Yamashita, Yoshioki; Sasaki, Makoto; Nara, Yoshihiko.

    1981-12-01

    In this report, the presumption about the mechanism having caused the power coefficient anomaly in Joyo during the 75 MW power-raising test in 1979 is described. After the previous report, the new information about the results of the post-irradiation examination and the analysis of the power coefficient of Joyo were able to be obtained. From these information, the mechanism of causing the anomaly was presumed as follows. In 50 MW operation, the fuel burnup reached about 10,000 MWD/ton at the end of second cycle, and produced fission gas was almost retained in fuel pellets. When the power was raised from 50 MW to 75 MW for the first time, the fission gas began to be released when 50 MW was somewhat exceeded. The fission gas release caused the temperature rise and cracking of fuel pellets, and elongated fuel stack length abruptly. These phenomena induced to enlarge the fuel expansion reactivity effect and Doppler reactivity effect, and caused the anomalous behavior of power coefficient. After reaching 75 MW, the fuel stack length did not respond normally to reactor power change, and the magnitude of power coefficient became smaller. The reactivity was lost considerably from the core after the anomaly. (Kako, I.)

  5. Unsuspected urological anomalies in asymptomatic cryptorchid boys

    International Nuclear Information System (INIS)

    Pappis, C.H.; Argianas, S.A.; Bousgas, D.; Athanasiades, E.; Pendeli Children's Hospital, Athens

    1988-01-01

    In a period of 6 years 144 asymptomatic boys with cryptorchidism, of mean age 7 ± SD 3.5 years, underwent orchiopexy. None of these boys referred to a history of a known urological anomaly, urinary tract infection haematuria, palpable mass in the renal region, bladder extrophy, epispadias, hypospadias or anorectal malformation. On the third day after orchiopexy an intravenous pyelography was done in every boy following testicular protection against irradiation. Ultrasonic investigation was not available at that time. There were minor urological abnormalities in 36 (25%) boys and major ones in 8 (5.5%) boys. A major anomaly is defined as one resulting in significant loss of renal substance (one case of single kidney and three cases of unilateral renal hypoplasia), or requiring surgical correction for conservation of the renal substance (one case of ureterocele, two cases of pelviureteric stenosis and one case of vesicoureteric stenosis with ipsilateral hydronephrosis). The unsuspected major urological abnormalities are usually ipsilateral to the more undescended testis. They may be associated with a hernia and are more frequent in bilateral cryptorchidism. In conclusion we encourage the routine use of IVP, or ultrasonic investigation or dynamic renal scanning (99 mTc -DTPA), if it is possible, in all patients undergoing orchiopexy for the detection of an unsuspected major renal anomaly. (orig.)

  6. Thermal Expansion Anomaly Regulated by Entropy

    Science.gov (United States)

    Liu, Zi-Kui; Wang, Yi; Shang, Shunli

    2014-11-01

    Thermal expansion, defined as the temperature dependence of volume under constant pressure, is a common phenomenon in nature and originates from anharmonic lattice dynamics. However, it has been poorly understood how thermal expansion can show anomalies such as colossal positive, zero, or negative thermal expansion (CPTE, ZTE, or NTE), especially in quantitative terms. Here we show that changes in configurational entropy due to metastable micro(scopic)states can lead to quantitative prediction of these anomalies. We integrate the Maxwell relation, statistic mechanics, and first-principles calculations to demonstrate that when the entropy is increased by pressure, NTE occurs such as in Invar alloy (Fe3Pt, for example), silicon, ice, and water, and when the entropy is decreased dramatically by pressure, CPTE is expected such as in anti-Invar cerium, ice and water. Our findings provide a theoretic framework to understand and predict a broad range of anomalies in nature in addition to thermal expansion, which may include gigantic electrocaloric and electromechanical responses, anomalously reduced thermal conductivity, and spin distributions.

  7. Conformal anomaly of super Wilson loop

    Energy Technology Data Exchange (ETDEWEB)

    Belitsky, A.V., E-mail: andrei.belitsky@asu.edu [Department of Physics, Arizona State University, Tempe, AZ 85287-1504 (United States)

    2012-09-11

    Classically supersymmetric Wilson loop on a null polygonal contour possesses all symmetries required to match it onto non-MHV amplitudes in maximally supersymmetric Yang-Mills theory. However, to define it quantum mechanically, one is forced to regularize it since perturbative loop diagrams are not well defined due to presence of ultraviolet divergences stemming from integration in the vicinity of the cusps. A regularization that is adopted by practitioners by allowing one to use spinor helicity formalism, on the one hand, and systematically go to higher orders of perturbation theory is based on a version of dimensional regularization, known as Four-Dimensional Helicity scheme. Recently it was demonstrated that its use for the super Wilson loop at one loop breaks both conformal symmetry and Poincare supersymmetry. Presently, we exhibit the origin for these effects and demonstrate how one can undo this breaking. The phenomenon is alike the one emerging in renormalization group mixing of conformal operators in conformal theories when one uses dimensional regularization. The rotation matrix to the diagonal basis is found by means of computing the anomaly in the Ward identity for the conformal boost. Presently, we apply this ideology to the super Wilson loop. We compute the one-loop conformal anomaly for the super Wilson loop and find that the anomaly depends on its Grassmann coordinates. By subtracting this anomalous contribution from the super Wilson loop we restore its interpretation as a dual description for reduced non-MHV amplitudes which are expressed in terms of superconformal invariants.

  8. Congenital anomalies and proximity to landfill sites.

    LENUS (Irish Health Repository)

    Boyle, E

    2004-01-01

    The occurrence of congenital anomalies in proximity to municipal landfill sites in the Eastern Region (counties Dublin, Kildare, Wicklow) was examined by small area (district electoral division), distance and clustering tendancies in relation to 83 landfills, five of which were major sites. The study included 2136 cases of congenital anomaly, 37,487 births and 1423 controls between 1986 and 1990. For the more populous areas of the region 50% of the population lived within 2-3 km of a landfill and within 4-5 km for more rural areas. In the area-level analysis, the standardised prevalence ratios, empirical and full Bayesian modelling, and Kulldorff\\'s spatial scan statistic found no association between the residential area of cases and location of landfills. In the case control analysis, the mean distance of cases and controls from the nearest landfill was similar. The odds ratios of cases compared to controls for increasing distances from all landfills and major landfills showed no significant difference from the baseline value of 1. The kernel and K methods showed no tendency of cases to cluster in relationship to landfills. In conclusion, congenital anomalies were not found to occur more commonly in proximity to municipal landfills.

  9. Variant Carvajal syndrome with additional dental anomalies.

    Science.gov (United States)

    Barber, Sophy; Day, Peter; Judge, Mary; Toole, Edell O'; Fayle, Stephen

    2012-09-01

    This paper aims to review the case of a girl who presented with a number of dental anomalies, in addition to unusual skin, nail and hair conditions. Tragically an undiagnosed cardiomyopathy caused unexpected sudden death. The case is discussed with reference to a number of dermatological and oral conditions which were considered as possible diagnoses. AW had been under long term dental care for prepubertal periodontitis, premature root resorption of primary teeth, soft tissue and dental anomalies, and angular cheilitis. Separately she had also been seen by several dermatologists with respect to palmar plantar keratosis, striae keratoderma, wiry hair and abnormal finger nails. Tragically the patient suffered a sudden unexpected death and the subsequent post mortem identified an undiagnosed dilated cardiomyopathy. The most likely diagnosis is that this case is a variant of Carvajal Syndrome with additional dental anomalies. To date we have been unable to identify mutations in the desoplakin gene. We aim to emphasise the importance of recognising these dental and dermatological signs when they present together as a potential risk factor for cardiac abnormalities. © 2012 The Authors. International Journal of Paediatric Dentistry © 2012 BSPD, IAPD and Blackwell Publishing Ltd.

  10. TFAP2B mutation and dental anomalies.

    Science.gov (United States)

    Tanasubsinn, Natchaya; Sittiwangkul, Rekwan; Pongprot, Yupada; Kawasaki, Katsushige; Ohazama, Atsushi; Sastraruji, Thanapat; Kaewgahya, Massupa; Kantaputra, Piranit Nik

    2017-08-01

    Mutations inTFAP2B has been reported in patients with isolated patent ductus arteriosus (PDA) and Char syndrome. We performed mutation analysis of TFAP2B in 43 patients with isolated PDA, 7 patients with PDA with other congenital heart defects and 286 patients with isolated tooth agenesis with or without other dental anomalies. The heterozygous c.1006G>A mutation was identified in 20 individuals. Those mutation carriers consisted of 1 patient with term PDA (1/43), 16 patients with isolated tooth agenesis with or without other dental anomalies (16/286; 5.6%), 1 patient with PDA and severe valvular aortic stenosis and tooth agenesis (1/4) and 2 normal controls (2/100; 1%). The mutation is predicted to cause an amino-acid substitution p.Val336Ile in the TFAP2B protein. Tfap2b expression during early mouse tooth development supports the association of TFAP2B mutation and dental anomalies. It is hypothesized that this incidence might have been the result of founder effect. Here we report for the first time that TFAP2B mutation is associated with tooth agenesis, microdontia, supernumerary tooth and root maldevelopment. In addition, we also found that TFAP2B mutations, the common causes of PDA in Caucasian, are not the common cause of PDA in Thai population.

  11. Flavorful hybrid anomaly-gravity mediation

    International Nuclear Information System (INIS)

    Gross, Christian; Hiller, Gudrun

    2011-01-01

    We consider supersymmetric models where anomaly and gravity mediation give comparable contributions to the soft terms and discuss how this can be realized in a five-dimensional brane world. The gaugino mass pattern of anomaly mediation is preserved in such a hybrid setup. The flavorful gravity-mediated contribution cures the tachyonic slepton problem of anomaly mediation. The supersymmetric flavor puzzle is solved by alignment. We explicitly show how a working flavor-tachyon link can be realized with Abelian flavor symmetries and give the characteristic signatures of the framework, including O(1) slepton mass splittings between different generations and between doublets and singlets. This provides opportunities for same flavor dilepton edge measurements with missing energy at the Large Hadron Collider (LHC). Rare lepton decay rates could be close to their current experimental limit. Compared to pure gravity mediation, the hybrid model is advantageous because it features a heavy gravitino which can avoid the cosmological gravitino problem of gravity-mediated models combined with leptogenesis.

  12. Combined analysis of magnetic and gravity anomalies using normalized source strength (NSS)

    Science.gov (United States)

    Li, L.; Wu, Y.

    2017-12-01

    Gravity field and magnetic field belong to potential fields which lead inherent multi-solution. Combined analysis of magnetic and gravity anomalies based on Poisson's relation is used to determinate homology gravity and magnetic anomalies and decrease the ambiguity. The traditional combined analysis uses the linear regression of the reduction to pole (RTP) magnetic anomaly to the first order vertical derivative of the gravity anomaly, and provides the quantitative or semi-quantitative interpretation by calculating the correlation coefficient, slope and intercept. In the calculation process, due to the effect of remanent magnetization, the RTP anomaly still contains the effect of oblique magnetization. In this case the homology gravity and magnetic anomalies display irrelevant results in the linear regression calculation. The normalized source strength (NSS) can be transformed from the magnetic tensor matrix, which is insensitive to the remanence. Here we present a new combined analysis using NSS. Based on the Poisson's relation, the gravity tensor matrix can be transformed into the pseudomagnetic tensor matrix of the direction of geomagnetic field magnetization under the homologous condition. The NSS of pseudomagnetic tensor matrix and original magnetic tensor matrix are calculated and linear regression analysis is carried out. The calculated correlation coefficient, slope and intercept indicate the homology level, Poisson's ratio and the distribution of remanent respectively. We test the approach using synthetic model under complex magnetization, the results show that it can still distinguish the same source under the condition of strong remanence, and establish the Poisson's ratio. Finally, this approach is applied in China. The results demonstrated that our approach is feasible.

  13. CT diagnosis of congenital anomalies of the central nervous system

    International Nuclear Information System (INIS)

    Mori, Koreaki

    1980-01-01

    In the diagnosis of central nervous system congenital anomalies, understanding of embryology of the central nervous system and pathophysiology of each anomaly are essential. It is important for clinical approach to central nervous system congenital anomalies to evaluate the size of the head and tention of the anterior fontanelle. Accurate diagnosis of congenital anomalies depends on a correlation of CT findings to clinical pictures. Clinical diagnosis of congenital anomalies should include prediction of treatability and prognosis, in addition to recognition of a disease. (author)

  14. Phenomenology of strongly coupled chiral gauge theories

    International Nuclear Information System (INIS)

    Bai, Yang; Berger, Joshua; Osborne, James; Stefanek, Ben A.

    2016-01-01

    A sector with QCD-like strong dynamics is common in models of non-standard physics. Such a model could be accessible in LHC searches if both confinement and big-quarks charged under the confining group are at the TeV scale. Big-quark masses at this scale can be explained if the new fermions are chiral under a new U(1) ′ gauge symmetry such that their bare masses are related to the U(1) ′ -breaking and new confinement scales. Here we present a study of a minimal GUT-motivated and gauge anomaly-free model with implications for the LHC Run 2 searches. We find that the first signatures of such models could appear as two gauge boson resonances. The chiral nature of the model could be confirmed by observation of a Z ′ γ resonance, where the Z ′ naturally has a large leptonic branching ratio because of its kinetic mixing with the hypercharge gauge boson.

  15. Splenic Anomalies of Shape, Size, and Location: Pictorial Essay

    Directory of Open Access Journals (Sweden)

    Adalet Elcin Yildiz

    2013-01-01

    Full Text Available Spleen can have a wide range of anomalies including its shape, location, number, and size. Although most of these anomalies are congenital, there are also acquired types. Congenital anomalies affecting the shape of spleen are lobulations, notches, and clefts; the fusion and location anomalies of spleen are accessory spleen, splenopancreatic fusion, and wandering spleen; polysplenia can be associated with a syndrome. Splenosis and small spleen are acquired anomalies which are caused by trauma and sickle cell disease, respectively. These anomalies can be detected easily by using different imaging modalities including ultrasonography, computed tomography, magnetic resonance imaging, and also Tc-99m scintigraphy. In this pictorial essay, we review the imaging findings of these anomalies which can cause diagnostic pitfalls and be interpreted as pathologic processes.

  16. Complete second branchial cleft anomaly presenting as a fistula and a tonsillar cyst: an interesting congenital anomaly.

    Science.gov (United States)

    Thottam, Prasad John; Bathula, Samba S; Poulik, Janet M; Madgy, David N

    2014-01-01

    Branchial cleft anomalies make up 30% of all pediatric neck masses, but complete second branchial cleft anomalies are extremely rare. We report an unusual case of a complete second branchial cleft anomaly that presented as a draining neck fistula and a tonsillar cyst in an otherwise healthy 3-month-old girl. At the age of 7 months, the patient had been experiencing feeding difficulties, and there was increasing concern about the risk of persistent infections. At that point, the anomaly was excised in its entirety. Our suspicion that the patient had a complete second branchial cleft anomaly was confirmed by imaging, surgical excision, and histopathologic analysis.

  17. Composite leptoquarks and anomalies in B-meson decays

    Energy Technology Data Exchange (ETDEWEB)

    Gripaios, Ben [Cavendish Laboratory, University of Cambridge,J.J. Thomson Avenue, Cambridge, CB3 0HE (United Kingdom); Nardecchia, M. [Cavendish Laboratory, University of Cambridge,J.J. Thomson Avenue, Cambridge, CB3 0HE (United Kingdom); DAMTP, University of Cambridge,Wilberforce Road, Cambridge, CB3 0WA (United Kingdom); Renner, S.A. [DAMTP, University of Cambridge,Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)

    2015-05-04

    We attempt to explain recent anomalies in semileptonic B decays at LHCb via a composite Higgs model, in which both the Higgs and an SU(2){sub L}-triplet leptoquark arise as pseudo-Goldstone bosons of the strong dynamics. Fermion masses are assumed to be generated via the mechanism of partial compositeness, which largely determines the leptoquark couplings and implies non-universal lepton interactions. The latter are needed to accommodate tensions in the b→sμμ dataset and to be consistent with a discrepancy measured at LHCb in the ratio of B{sup +}→K{sup +}μ{sup +}μ{sup −} to B{sup +}→K{sup +}e{sup +}e{sup −} branching ratios. The data imply that the leptoquark should have a mass of around a TeV. We find that the model is not in conflict with current flavour or direct production bounds, but we identify a few observables for which the new physics contributions are close to current limits and where the leptoquark is likely to show up in future measurements. The leptoquark will be pair-produced at the LHC and decay predominantly to third-generation quarks and leptons, and LHC13 searches will provide further strong bounds.

  18. Quantum electrodynamics of strong fields

    International Nuclear Information System (INIS)

    Greiner, W.

    1983-01-01

    Quantum Electrodynamics of Strong Fields provides a broad survey of the theoretical and experimental work accomplished, presenting papers by a group of international researchers who have made significant contributions to this developing area. Exploring the quantum theory of strong fields, the volume focuses on the phase transition to a charged vacuum in strong electric fields. The contributors also discuss such related topics as QED at short distances, precision tests of QED, nonperturbative QCD and confinement, pion condensation, and strong gravitational fields In addition, the volume features a historical paper on the roots of quantum field theory in the history of quantum physics by noted researcher Friedrich Hund

  19. Instabilities in strongly coupled plasmas

    CERN Document Server

    Kalman, G J

    2003-01-01

    The conventional Vlasov treatment of beam-plasma instabilities is inappropriate when the plasma is strongly coupled. In the strongly coupled liquid state, the strong correlations between the dust grains fundamentally affect the conditions for instability. In the crystalline state, the inherent anisotropy couples the longitudinal and transverse polarizations, and results in unstable excitations in both polarizations. We summarize analyses of resonant and non-resonant, as well as resistive instabilities. We consider both ion-dust streaming and dust beam-plasma instabilities. Strong coupling, in general, leads to an enhancement of the growth rates. In the crystalline phase, a resonant transverse instability can be excited.

  20. Impending ionospheric anomaly preceding the Iquique Mw8.2 earthquake in Chile on 2014 April 1

    Science.gov (United States)

    Guo, Jinyun; Li, Wang; Yu, Hongjuan; Liu, Zhimin; Zhao, Chunmei; Kong, Qiaoli

    2015-12-01

    To investigate the coupling relationship between great earthquake and ionosphere, the GPS-derived total electron contents (TECs) by the Center for Orbit Determination in Europe and the foF2 data from the Space Weather Prediction Center were used to analyse the impending ionospheric anomalies before the Iquique Mw8.2 earthquake in Chile on 2014 April 1. Eliminating effects of the solar and geomagnetic activities on ionosphere by the sliding interquartile range with the 27-day window, the TEC analysis results represent that there were negative anomalies occurred on 15th day prior to the earthquake, and positive anomalies appeared in 5th day before the earthquake. The foF2 analysis results of ionosonde stations Jicamarca, Concepcion and Ramey show that the foF2 increased by 40, 50 and 45 per cent, respectively, on 5th day before the earthquake. The TEC anomalous distribution indicates that there was a widely TEC decrement over the epicentre with the duration of 6 hr on 15th day before the earthquake. On 5th day before the earthquake, the TEC over the epicentre increased with the amplitude of 15 TECu, and the duration exceeded 6 hr. The anomalies occurred on the side away from the equator. All TEC anomalies in these days were within the bounds of equatorial anomaly zone where should be the focal area to monitor ionospheric anomaly before strong earthquakes. The relationship between ionospheric anomalies and geomagnetic activity was detected by the cross wavelet analysis, which implied that the foF2 was not affected by the magnetic activities on 15th day and 5th day prior to the earthquake, but the TECs were partially affected by anomalous magnetic activity during some periods of 5th day prior to the earthquake.