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1

Anomalies.  

ERIC Educational Resources Information Center

This theme issue on anomalies includes Web sites, CD-ROMs and software, videos, books, and additional resources for elementary and junior high school students. Pertinent activities are suggested, and sidebars discuss UFOs, animal anomalies, and anomalies from nature; and resources covering unexplained phenonmenas like crop circles, Easter Island,…

Online-Offline, 1999

1999-01-01

2

Singularity analysis of potential fields to enhance weak anomalies  

NASA Astrophysics Data System (ADS)

Geoanomalies generally are nonlinear, non-stationary and weak, especially in the land cover areas, however, the traditional methods of geoanomaly identification are usually based on linear theory. In past two decades, many power-law function models have been developed based on fractal concept in mineral exploration and mineral resource assessment, such that the density-area (C-A) model and spectrum-area model (S-A) suggested by Qiuming Cheng have played important roles in extracting geophysical and geochemical anomalies. Several power-law relationships are evident in geophysical potential fields, such as field value-distance, power spectrum-wave number as well as density-area models. The singularity index based on density-area model involves the first derivative transformation of the measure. Hence, we introduce the singularity analysis to develop a novel high-pass filter for extracting gravity and magnetic anomalies with the advantage of scale invariance. Furthermore, we suggest that the statistics of singularity indices can provide a new edge detection scheme for the gravity or magnetic source bodies. Meanwhile, theoretical magnetic anomalies are established to verify these assertions. In the case study from Nanling mineral district in south China and Qikou Depression in east China, compared with traditional geophysical filtering methods including multiscale wavelet analysis and total horizontal gradient methods, the singularity method enhances and extracts the weak anomalies caused by buried magmatic rocks more effectively, and provides more distinct boundary information of rocks. Moreover, the singularity mapping results have good correspondence relationship with both the outcropping rocks and known mineral deposits to support future mineral resource exploration. The singularity method based on fractal analysis has potential to be a new useful theory and technique for processing gravity and magnetic anomaly data.

Chen, G.; Cheng, Q.; Liu, T.

2013-12-01

3

Thermodynamic, Dynamic and Structural Anomalies for Shoulder-like potentials  

E-print Network

becomes a deep well the regions in the pressure-temperature phase diagram where the three anomalies- temperature phase diagram with density, diffusion and structural anomalies. However, if the closest scale a simple two- body isotropic potential capable of describing the complicated behavior present in water

Barbosa, Marcia C. B.

4

Streaming electrical potential anomaly along faults in geothermal areas  

NASA Astrophysics Data System (ADS)

Electrical potential anomalies are often measured associated with geothermal areas and volcanoes. In these systems, fluid flow is usually mostly restricted to faults and fracture networks. An equation describing electrical potential anomalies of electrokinetic nature associated with fluid upflow induced by a thermal source along faults is derived. The electrical potential anomaly is related to the depth of the thermal reservoir, the temperature difference between the surface and the reservoir of the geothermal area, the thermal expansion of water, and the streaming electrical potential coupling coefficient in the fault zone. A quantitative calculation of the electrokinetic anomaly is provided by comparing this model to a self-potential survey of the Cerro-Prieto geothermal field [Fitterman and Corwin, 1982]. The predictions of the model agree well with the field measurements.

Revil, A.; Pezard, P. A.

5

Modeling of self-potential anomalies near vertical dikes.  

USGS Publications Warehouse

The self-potential (SP) Green's function for an outcropping vertical dike is derived from solutions for the dc resistivity problem for the same geometry. The Green's functions are numerically integrated over rectangular source regions on the contacts between the dike and the surrounding material to obtain the SP anomaly. The analysis is valid for thermoelectrical source mechanisms. Two types of anomalies can be produced by this geometry. When the two source planes are polarized in opposite directions, a monopolar anomaly is produced. This corresponds to the thermoelectrical properties of the dike being in contrast with the surrounding material. When the thermoelectric coefficients change monotonically across the dike, a dipolar anomaly is produced. In either case positive and negative anomalies are possible, and the greatest variation in potential will occur in the most resistive regions. -Author

Fitterman, D.V.

1983-01-01

6

Inversion of self-potential anomalies in mineral exploration  

NASA Astrophysics Data System (ADS)

A method for the inversion of self-potential anomalies over spherical, cylindrical, and sheet-like sources is proposed. In this method, the computer calculates the initial solution which is modified in an iterative process using nonlinear least-squares regression by employing the Marquardt algorithm. A computer program in FORTRAN 77, directly executable on a VAX-11/750 computer is presented.

Ram Babu, H. V.; Atchuta Rao, D.

7

Clinical and Radiological Characteristics of 22 Children with SHOX Anomalies and Familial Short Stature Suggestive of Léri-Weill Dyschondrosteosis  

Microsoft Academic Search

Aims: To describe genetic, clinical, anthropometric and radiological characteristics of 22 children with SHOX gene anomalies and familial short stature suggestive of Léri-Weill dyschondrosteosis. Methods: Monocentric retrospective observational study. Results: Six children (27%) presented with deletions located downstream of SHOX (mean height –1.4 ± 0.9 SDS) and 16 (68%) with either deletions encompassing SHOX, intragenic deletions or point mutations of

Anne-Sophie Salmon-Musial; Myriam Rosilio; Michel David; Céline Huber; Emmanuel Pichot; Valérie Cormier-Daire; Marc Nicolino

2011-01-01

8

Spectral action, Weyl anomaly and the Higgs-dilaton potential  

NASA Astrophysics Data System (ADS)

We show how the bosonic spectral action emerges from the fermionic action by the renormalization flow in the presence of a dilaton and the Weyl anomaly. The induced action comes out to be basically the Chamseddine-Connes spectral action introduced in the context of noncommutative geometry. The entire spectral action describes gauge and Higgs fields coupled with gravity. We then consider the effective potential and show, that it has the desired features of a broken and an unbroken phase, with the roll down.

Andrianov, A. A.; Kurkov, M. A.; Lizzi, Fedele

2011-10-01

9

Rapid fluid disruption: A source for self-potential anomalies on volcanoes  

NASA Astrophysics Data System (ADS)

Self-potential (SP) anomalies observed above suspected magma reservoirs, dikes, etc., on various volcanoes (Kilauea, Hawaii; Mount Unzen, Japan; Piton de la Fournaise, Reunion Island; Miyake Jima, Japan) result from transient surface electric fields of tens of millivolts per kilometer and generally have a positive polarity. These SP anomalies are usually attributed to electrokinetic effects where properties controlling this process are poorly constrained. We propose an alternate explanation that contributions to electric fields of correct polarity should be expected from charge generation by fluid vaporization/disruption. As liquids are vaporized or removed as droplets by gas transport away from hot dike intrusions, both charge generation and local increase in electrical resistivity by removal of fluids should occur. We report laboratory observations of electric fields in hot rock samples generated by pulses of fluid (water) through the rock at atmospheric pressure. These indicate the relative amplitudes of rapid fluid disruption (RFD) potentials and electrokinetic potentials to be dramatically different and the signals are opposite in sign. Above vaporization temperatures, RFD effects of positive sign in the direction of gas flow dominate, whereas below these temperatures, effects of negative sign dominate. This suggests that the primary contribution to observed self-potential anomalies arises from gas-related charge transport processes at temperatures high enough to produce vigorous boiling and vapor transport. At lower temperatures, the primary contribution is from electrokinetic effects modulated perhaps by changing electrical resistivity and RFD effects from high-pressure but low-temperature CO2 and SO2 gas flow ripping water molecules from saturated crustal rocks. If charge generation is continuous, as could well occur above a newly emplaced dike, positive static potentials will be set up that could be sustained for many years, and the simplest method for identifying these hot, active regions would be to identify the SP anomalies they generate.

Johnston, M. J. S.; Byerlee, J. D.; Lockner, D.

2001-01-01

10

Rapid fluid disruption: A source for self-potential anomalies on volcanoes  

USGS Publications Warehouse

Self-potential (SP) anomalies observed above suspected magma reservoirs, dikes, etc., on various volcanoes (Kilauea, Hawaii; Mount Unzen, Japan; Piton de la Fournaise, Reunion Island, Miyake Jima, Japan) result from transient surface electric fields of tens of millivolts per kilometer and generally have a positive polarity. These SP anomalies are usually attributed to electrokinetic effects where properties controlling this process are poorly constrained. We propose an alternate explanation that contributions to electric fields of correct polarity should be expected from charge generation by fluid vaporization/disruption. As liquids are vaporized or removed as droplets by gas transport away from hot dike intrusions, both charge generation and local increase in electrical resistivity by removal of fluids should occur. We report laboratory observations of electric fields in hot rock samples generated by pulses of fluid (water) through the rock at atmospheric pressure. These indicate the relative amplitudes of rapid fluid disruption (RFD) potentials and electrokinetic potentials to be dramatically different and the signals are opposite in sign. Above vaporization temperatures, RFD effects of positive sign in the direction of gas flow dominate, whereas below these temperatures, effects of negative sign dominate. This suggests that the primary contribution to observed self-potential anomalies arises from gas-related charge transport processes at temperatures high enough to produce vigorous boiling and vapor transport. At lower temperatures, the primary contribution is from electrokinetic effects modulated perhaps by changing electrical resistivity and RFD effects from high-pressure but low-temperature CO2 and SO2 gas flow ripping water molecules from saturated crustal rocks. If charge generation is continuous, as could well occur above a newly emplaced dike, positive static potentials will be set up that could be sustained for many years, and the simplest method for identifying these hot, active regions would be to identify the SP anomalies they generate.

Johnston, M.J.S.; Byerlee, J.D.; Lockner, D.

2001-01-01

11

Softness dependence of the anomalies for the continuous shouldered well potential.  

PubMed

By molecular dynamic simulations we study a system of particles interacting through a continuous isotropic pairwise core-softened potential consisting of a repulsive shoulder and an attractive well. The model displays a phase diagram with three fluid phases: a gas-liquid critical point, a liquid-liquid critical point, and anomalies in density, diffusion, and structure. The hierarchy of the anomalies is the same as for water. Here we study in a systematic way the effect on the anomalies of varying the softness of the potential. We find that, making the soft-core steeper and more penetrable, the regions of density and diffusion anomalies contract in the T-rho plane, while the region of structural anomaly is weakly affected. Therefore, a liquid can have anomalous structural behavior without having density or diffusion anomalies. We show that, by considering as effective distances those corresponding to the maxima of the first two peaks of the radial distribution function g(r) in the high-density liquid, we can generalize to continuous two-scale potentials a criterion for the occurrence of the anomalies of density and diffusion, originally proposed for discontinuous potentials. However, we observe that the knowledge of the structural behavior within the first two coordination shells of the liquid is not enough to establish, in general, the occurrence of the anomalies. By introducing the density derivative of the cumulative order integral of the excess entropy, measuring shell by shell the amount of order in the liquid, we show that the anomalous behavior is regulated by the structural order at distances as large as the fourth coordination shell. By comparing the results for different softness of the potential, we conclude that the disappearance of the density and diffusion anomalies for the steeper potentials is due to a more structured short-range order. All these results increase our understanding on how, knowing the interaction potential, we can evaluate the possible presence of anomalies for a liquid. PMID:20815580

Vilaseca, Pol; Franzese, Giancarlo

2010-08-28

12

Structure order, local potentials, and physical anomalies of water ice  

E-print Network

Hydrogen-bond forms a pair of asymmetric, coupled, H-bridged oscillators with ultra-short-range interactions and memory. hydrogen bond cooperative relaxation and the associated binding electron entrapment and nonbonding electron polarization discriminate water and ice from other usual materials in the physical anomalies. As a strongly correlated fluctuating system, water prefers the statistically mean of tetrahedrally-coordinated structure with a supersolid skin that is elastic, polarized, ice like, hydrophobic, with 3/4 density.

Chang Q Sun

2014-07-11

13

Evaluating Cenozoic equatorial sediment deposition anomalies for potential paleoceanographic and Pacific plate motion applications  

NASA Astrophysics Data System (ADS)

If equatorial sediments form characteristic deposits around the equator, they may help to resolve the amount of northwards drift of the Pacific tectonic plate. Relevant to this issue, it has been shown that 230Th has been accumulating on the equatorial seabed faster than its production from radioactive decay in the overlying water column during the Holocene (Marcantonio et al. in Paleoceanography 16:260-267, 2001). Some researchers have argued that this reflects the deposition of particles with adsorbed 230Th carried by bottom currents towards the equator ("focusing"). If correct, this effect may combine with high pelagic productivity, which is also centered on the equator, to yield a characteristic signature of high accumulation rates marking the paleoequator in older deposits. Here we evaluate potential evidence that such an equatorial feature existed in the geological past. Seismic reflection data from seven meridional transects suggest that a band of equatorially enhanced accumulation of restricted latitude was variably developed, both spatially and temporally. It is absent in the interval 14.25-20.1 Ma but is well developed for the interval 8.55-14.25 Ma. We also examined eolian dust accumulation rate histories generated from scientific drilling data. A dust accumulation rate anomaly near the modern equator, which is not obviously related to the inter-tropical convergence zone, is interpreted as caused by focusing. Accumulation rates of Ba and P2O5 (proxies of export production) reveal a static equatorial signature, which suggests that the movement of the Pacific plate over the period 10-25 Ma was modest. The general transition from missing to well-developed focusing signatures around 14.25 Ma in the seismic data coincides with the mid-Miocene development of the western boundary current off New Zealand. This current supplies the Pacific with deep water from Antarctica, and could therefore imply a potential paleoceanographic or paleoclimatic origin. At 10.05-14.25 Ma, the latitudes of the seismic anomalies are up to ~2° different from the paleoequator predicted by Pacific plate-hotspot models, suggesting potentially a small change in the hotspot latitudes relative to the present day (although this inference depends on the precise form of the deposition around the equator). The Ba and P2O5 anomalies, on the other hand, are broadly compatible with plate models predicting slow northward plate movement over 10-25 Ma.

Mitchell, Neil C.; Dubois, Nathalie

2014-03-01

14

Developing Global Climate Anomalies Suggest Potential Disease Risks For 2006 – 2007  

Technology Transfer Automated Retrieval System (TEKTRAN)

Climate has a demonstrated impact on infectious diseases and increased disease transmission has been linked to the El Niño/southern Oscillation (ENSO) phenomenon. The Climate Prediction Center of the National Oceanic and Atmospheric Administration has recently issued an unscheduled El Niño advisory,...

15

EVAREST - Evaluation of geological models by joint interpretation of potential field anomalies  

NASA Astrophysics Data System (ADS)

Structural geological models are often based on the integration of different geophysical datasets. During the last years an increasing interest in the potential field methods, i.e. gravimetry and magnetic, can be observed, even though data acquisition can cause considerable costs and logistic effort. Therefore, the specific advantages and disadvantages of the different methods were analyzed. In a case study, which was conducted in cooperation with RWE Dea and which is located in northern Germany, it was studied to which level of detail gravity and magnetic anomalies can be interpreted jointly by 3D forward modelling. Special attention was paid to the individual residuals, i.e. those parts of the gravity and magnetic anomalies which could not be interpreted satisfactorily by the joint structural / physical model. In a subsequent stage of the workflow this information was analyzed individually for each dataset to improve the geological interpretation and to identify and localize the sources of the anomalies in more detail. For the discussed study several potential field datasets of different resolution were available, which were first analyzed by means of field transformation. While the gravity anomalies are mainly related to the occurrence of salt structures, the magnetic anomalies seem to be controlled by deep structures, most probably by the magnetic basement. Some local magnetic anomalies with amplitudes of less than 10 nT can be related to the rim synclines of the salt structures as well as to buried Pleistocene subglacial valleys. 3D forward models, constrained by existing structural information and rock physical data, have shown that, e.g., a common fitting of both anomaly fields is not possible if homogenous densities and magnetizations are assigned to the different lithological units and while considering the geometry of the source bodies to be the same for both potential field anomalies. To explain the magnetic anomalies a more detailed differentiation of the source bodies in terms of thin layers is required, while for the interpretation of the gravity anomalies vertical density gradients must be considered for specific lithologies. Furthermore, from the magnetic anomalies ideas about the maximum depth of source bodies can be derived.

Skiba, Peter; Gabriel, Gerald; Krawczyk, CharLotte M.

2014-05-01

16

Inversion of Self Potential Anomalies with Multilayer Perceptron Neural Networks  

NASA Astrophysics Data System (ADS)

This study investigates the inverse solution on a buried and polarized sphere-shaped body using the self-potential method via multilayer perceptron neural networks (MLPNN). The polarization angle ( ?), depth to the centre of sphere ( h), electrical dipole moment ( K) and the zero distance from the origin ( x 0) were estimated. For testing the success of the MLPNN for sphere model, parameters were also estimated by the traditional Damped Least Squares (Levenberg-Marquardt) inversion technique (DLS). The MLPNN was first tested on a synthetic example. The performance of method was also tested for two S/N ratios (5 % and 10 %) by adding noise to the same synthetic data, the estimated model parameters with MLPNN and DLS method are satisfactory. The MLPNN also applied for the field data example in ?zmir, Urla district, Turkey, with two cross-section data evaluated by MLPNN and DLS, and the two methods showed good agreement.

Kaftan, Ilknur; S?nd?rg?, Petek; Akdemir, Özer

2014-08-01

17

Anomaly in dispersion intermolecular potential produced by intense radation field  

NASA Astrophysics Data System (ADS)

It is predicted that a gap of 2? E/3 1/2 appears in the dispersion potential for a pair of ground-state (identical) atoms, or molecules, at distance R such that ?? + (4?? 0) -1( ? 2/3 R3)(1 - 3 cos 2?) = 0, where ? is the electric dipole moment, E is the field strength of an intense radiation field and ? is the angle between the polarization direction of the field and R. The detuning term ? is ? 0-? where ? 0 is the transition frequency of the atom or molecule, and ? is that of the field. The gap is of the order of 10 11 Hz when the intensity of the radiation field is a few MW/cm 2.

Mizushima, Masataka; Power, Edwin A.

1980-03-01

18

Revealing unexposed sources of potential field anomalies at Outokumpu ore province  

NASA Astrophysics Data System (ADS)

Prospecting at Outokumpu Cu-ore province, Central Fennoscandian Shield has led to discoveries of several deposits within Outokumpu type association rocks, close to bedrock surface. Reflection seismic studies have indicated that this association may be present in different deep locations down to a depth of several kilometers. A new combined analysis of all available geodata is under way to produce a CEM-model of uppermost crust in the vicinity of the province. In addition to direct and inversion modeling the potential field studies include Fourier analyses of source depths and a comparison of anomaly change between 1980 and 2013 aeromagnetic surveys plus gravity anomalies to assist characterizing geological formations at depth by their remanent magnetization. Regional anomalies of potential fields are aimed to be defined by hierarchical CEM-models by magnetic and gravity anomaly grids of the Fennoscandian Shield and corresponding regional petrophysical data sets. The ultimate goal of the potential field interpretation is to contribute to recommendations for deep ore prospecting in a shield environment.

Korhonen, Juha; Leväniemi, Hanna; Kukkonen, Ilmo

2013-04-01

19

SUGGESTIONS FOR COLLECTION AND REPORTING OF CHEMOSENSORY (OLFACTORY) EVENT-RELATED POTENTIALS  

EPA Science Inventory

Chemosensory event-related potentials hold great promise for furthering understanding of the olfactory system and the processing of olfactory information. ollection of this type of data has been difficult and suggestions are presented to aid investigators new to this field. ugges...

20

Extreme sensitivity of the spin-splitting and 0.7 anomaly to confining potential in one-dimensional nanoelectronic devices.  

PubMed

Quantum point contacts (QPCs) have shown promise as nanoscale spin-selective components for spintronic applications and are of fundamental interest in the study of electron many-body effects such as the 0.7 × 2e(2)/h anomaly. We report on the dependence of the 1D Landé g-factor g and 0.7 anomaly on electron density and confinement in QPCs with two different top-gate architectures. We obtain g values up to 2.8 for the lowest 1D subband, significantly exceeding previous in-plane g-factor values in AlGaAs/GaAs QPCs and approaching that in InGaAs/InP QPCs. We show that g is highly sensitive to confinement potential, particularly for the lowest 1D subband. This suggests careful management of the QPC's confinement potential may enable the high g desirable for spintronic applications without resorting to narrow-gap materials such as InAs or InSb. The 0.7 anomaly and zero-bias peak are also highly sensitive to confining potential, explaining the conflicting density dependencies of the 0.7 anomaly in the literature. PMID:22830617

Burke, A M; Klochan, O; Farrer, I; Ritchie, D A; Hamilton, A R; Micolich, A P

2012-09-12

21

Interpretation of Self-Potential Anomalies Using Constitutive Relationships for Electrochemical and Thermoelectric Coupling Coefficients  

SciTech Connect

Constitutive relationships for electrochemical and thermoelectric cross-coupling coefficients are derived using ionic mobilities, applying a general derivative of chemical potential and employing the zero net current condition. The general derivative of chemical potential permits thermal variations which give rise to the thermoelectric effect. It also accounts for nonideal solution behavior. An equation describing electric field strength is similarly derived with the additional assumption of electrical neutrality in the fluid Planck approximation. The Planck approximation implies that self-potential (SP) is caused only by local sources and also that the electric field strength has only first order spatial variations. The derived relationships are applied to the NaCl-KCl concentration cell with predicted and measured voltages agreeing within 0.4 mV. The relationships are also applied to the Long Valley and Yellowstone geothermal systems. There is a high degree of correlation between predicted and measured SP response for both systems, giving supporting evidence for the validity of the approach. Predicted SP amplitude exceeds measured in both cases; this is a possible consequence of the Planck approximation. Electrochemical sources account for more than 90% of the predicted response in both cases while thermoelectric mechanisms account for the remaining 10%; electrokinetic effects are not considered. Predicted electrochemical and thermoelectric voltage coupling coefficients are comparable to values measured in the laboratory. The derived relationships are also applied to arbitrary distributions of temperature and fluid composition to investigate the geometric diversity of observed SP anomalies. Amplitudes predicted for hypothetical saline spring and hot spring environments are less than 40 mV. In contrast, hypothetical near surface steam zones generate very large amplitudes, over 2 V in one case. These results should be viewed with some caution due to the uncertain validity of the Planck approximation for these conditions. All amplitudes are controlled by electrochemical mechanisms. Polarities are controlled by the curvature of the concentration or thermal profile. Concave upward thermal profiles produce positive anomalies, for constant fluid concentrations, whereas concave upward concentration profiles produce negative anomalies. Concave downward concentration profiles are characterized by small negative closures bounding a larger, positive SP anomaly.

Knapp, R. B.; Kasameyer, P. W.

1988-01-01

22

Sharing of Potential Nest Sites by Etheostoma olmstedi Males Suggests Mutual Tolerance in an Alloparental Species  

PubMed Central

When reproductive competitors tolerate or cooperate with one another, they may gain particular benefits, such as collectively guarding resources or attracting mates. Shared resources may be those essential to reproduction, such as a breeding site or nest. Using the tessellated darter, a species where males but not females compete over potential nest sites, we examined site use and sharing under controlled conditions of differing competitor density. Sharing was observed even when competitor density was low and individuals could have each occupied a potential nest site without same-sex sharing. Males were more likely to share a nest site with one other when the difference in size between them was larger rather than smaller. There was no evidence that female sharing was dependent on their relative size. Fish were generally more likely to use and share larger sites, in accordance with the greater relative surface area they offered. We discuss how one or both sharing males may potentially benefit, and how male sharing of potential nest sites could relate to female mating preferences. Tessellated darter males are known to provide alloparental care for eggs but this occurs without any social contact between the alloparent and the genetic father of the young. Thus, the suggestion that they may also share sites and maintain social contact with reproductive competitors highlights the importance of increased focus on the potential complexity of reproductive systems. PMID:23468853

Stiver, Kelly A.; Wolff, Stephen H.; Alonzo, Suzanne H.

2013-01-01

23

Event-related potential evidence suggesting voters remember political events that never happened.  

PubMed

Voters tend to misattribute issue positions to political candidates that are consistent with their partisan affiliation, even though these candidates have never explicitly stated or endorsed such stances. The prevailing explanation in political science is that voters misattribute candidates' issue positions because they use their political knowledge to make educated but incorrect guesses. We suggest that voter errors can also stem from a different source: false memories. The current study examined event-related potential (ERP) responses to misattributed and accurately remembered candidate issue information. We report here that ERP responses to misattributed information can elicit memory signals similar to that of correctly remembered old information--a pattern consistent with a false memory rather than educated guessing interpretation of these misattributions. These results suggest that some types of voter misinformation about candidates may be harder to correct than previously thought. PMID:23202775

Coronel, Jason C; Federmeier, Kara D; Gonsalves, Brian D

2014-03-01

24

Global Climate Anomalies and Potential Infectious Disease Risks: 2014-2015  

PubMed Central

Background: The El Niño/Southern Oscillation (ENSO) is a global climate phenomenon that impacts human infectious disease risk worldwide through droughts, floods, and other climate extremes. Throughout summer and fall 2014 and winter 2015, El Niño Watch, issued by the US National Oceanic and Atmospheric Administration, assessed likely El Niño development during the Northern Hemisphere fall and winter, persisting into spring 2015. Methods: We identified geographic regions where environmental conditions may increase infectious disease transmission if the predicted El Niño occurs using El Niño indicators (Sea Surface Temperature [SST], Outgoing Longwave Radiation [OLR], and rainfall anomalies) and literature review of El Niño-infectious disease associations. Results: SSTs in the equatorial Pacific and western Indian Oceans were anomalously elevated during August-October 2014, consistent with a developing weak El Niño event. Teleconnections with local climate is evident in global precipitation patterns, with positive OLR anomalies (drier than average conditions) across Indonesia and coastal southeast Asia, and negative anomalies across northern China, the western Indian Ocean, central Asia, north-central and northeast Africa, Mexico/Central America, the southwestern United States, and the northeastern and southwestern tropical Pacific. Persistence of these conditions could produce environmental settings conducive to increased transmission of cholera, dengue, malaria, Rift Valley fever, and other infectious diseases in regional hotspots as during previous El Niño events. Discussion and Conclusions: The current development of weak El Niño conditions may have significant potential implications for global public health in winter 2014-spring 2015. Enhanced surveillance and other preparedness measures in predicted infectious disease hotspots could mitigate health impacts.

Chretien, Jean-Paul; Anyamba, Assaf; Small, Jennifer; Britch, Seth; Sanchez, Jose L.; Halbach, Alaina C.; Tucker, Compton; Linthicum, Kenneth J.

2015-01-01

25

Sexual and postmating reproductive isolation between allopatric Drosophila montana populations suggest speciation potential  

PubMed Central

Background Widely distributed species with populations adapted to different environmental conditions can provide valuable opportunities for tracing the onset of reproductive incompatibilities and their role in the speciation process. Drosophila montana, a D. virilis group species found in high latitude boreal forests in Nearctic and Palearctic regions around the globe, could be an excellent model system for studying the early stages of speciation, as a wealth of information concerning this species' ecology, mating system, life history, genetics and phylogeography is available. However, reproductive barriers between populations have hereto not been investigated. Results We report both pre- and postmating barriers to reproduction between flies from European (Finnish) and North American (Canadian) populations of Drosophila montana. Using a series of mate-choice designs, we show that flies from these two populations mate assortatively (i.e., exhibit significant sexual isolation) while emphasizing the importance of experimental design in these kinds of studies. We also assessed potential postmating isolation by quantifying egg and progeny production in intra- and interpopulation crosses and show a significant one-way reduction in progeny production, affecting both male and female offspring equally. Conclusion We provide evidence that allopatric D. montana populations exhibit reproductive isolation and we discuss the potential mechanisms involved. Our data emphasize the importance of experimental design in studies on premating isolation between recently diverged taxa and suggest that postmating barriers may be due to postcopulatory-prezygotic mechanisms. D. montana populations seem to be evolving multiple barriers to gene flow in allopatry and our study lays the groundwork for future investigations of the genetic and phenotypic mechanisms underlying these barriers. PMID:21396136

2011-01-01

26

Widespread Sequence Variations in VAMP1 across Vertebrates Suggest a Potential Selective Pressure from Botulinum Neurotoxins  

PubMed Central

Botulinum neurotoxins (BoNT/A-G), the most potent toxins known, act by cleaving three SNARE proteins required for synaptic vesicle exocytosis. Previous studies on BoNTs have generally utilized the major SNARE homologues expressed in brain (VAMP2, syntaxin 1, and SNAP-25). However, BoNTs target peripheral motor neurons and cause death by paralyzing respiratory muscles such as the diaphragm. Here we report that VAMP1, but not VAMP2, is the SNARE homologue predominantly expressed in adult rodent diaphragm motor nerve terminals and in differentiated human motor neurons. In contrast to the highly conserved VAMP2, BoNT-resistant variations in VAMP1 are widespread across vertebrates. In particular, we identified a polymorphism at position 48 of VAMP1 in rats, which renders VAMP1 either resistant (I48) or sensitive (M48) to BoNT/D. Taking advantage of this finding, we showed that rat diaphragms with I48 in VAMP1 are insensitive to BoNT/D compared to rat diaphragms with M48 in VAMP1. This unique intra-species comparison establishes VAMP1 as a physiological toxin target in diaphragm motor nerve terminals, and demonstrates that the resistance of VAMP1 to BoNTs can underlie the insensitivity of a species to members of BoNTs. Consistently, human VAMP1 contains I48, which may explain why humans are insensitive to BoNT/D. Finally, we report that residue 48 of VAMP1 varies frequently between M and I across seventeen closely related primate species, suggesting a potential selective pressure from members of BoNTs for resistance in vertebrates. PMID:25010769

Peng, Lisheng; Adler, Michael; Demogines, Ann; Borrell, Andrew; Liu, Huisheng; Tao, Liang; Tepp, William H.; Zhang, Su-Chun; Johnson, Eric A.; Sawyer, Sara L.; Dong, Min

2014-01-01

27

Resilient RTN Fast Spiking in Kv3.1 Null Mice Suggests Redundancy in the Action Potential Repolarization Mechanism  

E-print Network

Resilient RTN Fast Spiking in Kv3.1 Null Mice Suggests Redundancy in the Action Potential. Joho, and John R. Huguenard. Resilient RTN fast spiking in Kv3.1 null mice suggests redundancy.2001. Fast spiking (FS), GABAergic neurons of the reticular thalamic nucleus (RTN) are capable of firing high

Huguenard, John R.

28

Chromosome 3 Anomalies Investigated by Genome Wide SNP Analysis of Benign, Low Malignant Potential and Low Grade Ovarian Serous Tumours  

PubMed Central

Ovarian carcinomas exhibit extensive heterogeneity, and their etiology remains unknown. Histological and genetic evidence has led to the proposal that low grade ovarian serous carcinomas (LGOSC) have a different etiology than high grade carcinomas (HGOSC), arising from serous tumours of low malignant potential (LMP). Common regions of chromosome (chr) 3 loss have been observed in all types of serous ovarian tumours, including benign, suggesting that these regions contain genes important in the development of all ovarian serous carcinomas. A high-density genome-wide genotyping bead array technology, which assayed >600,000 markers, was applied to a panel of serous benign and LMP tumours and a small set of LGOSC, to characterize somatic events associated with the most indolent forms of ovarian disease. The genomic patterns inferred were related to TP53, KRAS and BRAF mutations. An increasing frequency of genomic anomalies was observed with pathology of disease: 3/22 (13.6%) benign cases, 40/53 (75.5%) LMP cases and 10/11 (90.9%) LGOSC cases. Low frequencies of chr3 anomalies occurred in all tumour types. Runs of homozygosity were most commonly observed on chr3, with the 3p12-p11 candidate tumour suppressor region the most frequently homozygous region in the genome. An LMP harboured a homozygous deletion on chr6 which created a GOPC-ROS1 fusion gene, previously reported as oncogenic in other cancer types. Somatic TP53, KRAS and BRAF mutations were not observed in benign tumours. KRAS-mutation positive LMP cases displayed significantly more chromosomal aberrations than BRAF-mutation positive or KRAS and BRAF mutation negative cases. Gain of 12p, which harbours the KRAS gene, was particularly evident. A pathology review reclassified all TP53-mutation positive LGOSC cases, some of which acquired a HGOSC status. Taken together, our results support the view that LGOSC could arise from serous benign and LMP tumours, but does not exclude the possibility that HGOSC may derive from LMP tumours. PMID:22163003

Birch, Ashley H.; Arcand, Suzanna L.; Oros, Kathleen K.; Rahimi, Kurosh; Watters, A. Kevin; Provencher, Diane; Greenwood, Celia M.; Mes-Masson, Anne-Marie; Tonin, Patricia N.

2011-01-01

29

Frequency of births with potentially avoidable serious chromosomal anomalies in EEC countries, 1979-1982.  

PubMed Central

Child bearing at an early age and prenatal cytogenetic diagnosis in pregnant women of advanced age, combined with selective abortion, make it possible to avoid the birth of many children with serious chromosomal anomalies. To see how many of such births were still avoidable in Europe, data from 16 regional EUROCAT registers of congenital anomalies in nine EEC countries were analysed. In the period 1979-1982 about 30% of children with unbalanced anomalies of autosomes were born (live- and still-births) to mothers over 35 years of age. This amounts to an estimated 1300 cases yearly in the entire population of the nine countries. The approach shows the possible use of registry data for monitoring effects of avoidance strategies. PMID:3251007

Ten Kate, L P; Dolk, H; Cornel, M C; De Wals, P; Te Meerman, G J; Lechat, M F; Weatherall, J A

1988-01-01

30

PERINATAL EXPOSURE TO ENDOCRINE DISRUPTING CHEMICALS: POTENTIAL ROLE OF HORMONAL ALTERATIONS IN INITIATING ADULT REPRODUCTIVE ANOMALIES  

EPA Science Inventory

The primary hypothesis to be tested in this series of studies is whether or not exposure to environmental agents, during certain key periods of development, will increase the risk of specific anomalies of the reproductive system. Embedded in this hypothesis is the assumption that...

31

Self-Propagative Replication of A? Oligomers Suggests Potential Transmissibility in Alzheimer Disease  

PubMed Central

The aggregation of amyloid-? (A?) peptide and its deposition in parts of the brain form the central processes in the etiology of Alzheimer disease (AD). The low-molecular weight oligomers of A? aggregates (2 to 30 mers) are known to be the primary neurotoxic agents whose mechanisms of cellular toxicity and synaptic dysfunction have received substantial attention in the recent years. However, how these toxic agents proliferate and induce widespread amyloid deposition throughout the brain, and what mechanism is involved in the amplification and propagation of toxic oligomer species, are far from clear. Emerging evidence based on transgenic mice models indicates a transmissible nature of A? aggregates and implicates a prion-like mechanism of oligomer propagation, which manifests as the dissemination and proliferation of A? toxicity. Despite accumulating evidence in support of a transmissible nature of A? aggregates, a clear, molecular-level understanding of this intriguing mechanism is lacking. Recently, we reported the characterization of unique replicating oligomers of A?42 (12–24 mers) in vitro called Large Fatty Acid-derived Oligomers (LFAOs) (Kumar et al., 2012, J. Biol. Chem). In the current report, we establish that LFAOs possess physiological activity by activating NF-?B in human neuroblastoma cells, and determine the experimental parameters that control the efficiency of LFAO replication by self-propagation. These findings constitute the first detailed report on monomer – oligomer lateral propagation reactions that may constitute potential mechanism governing transmissibility among A? oligomers. These data support the previous reports on transmissible mechanisms observed in transgenic animal models. PMID:25365422

Kumar, Amit; Pate, Kayla M.; Moss, Melissa A.; Dean, Dexter N.; Rangachari, Vijayaraghavan

2014-01-01

32

Potential cancer-related role of circadian gene TIMELESS suggested by expression profiling and in vitro analyses  

PubMed Central

Background The circadian clock and cell cycle are two global regulatory systems that have pervasive behavioral and physiological effects on eukaryotic cells, and both play a role in cancer development. Recent studies have indicated that the circadian and cell cycle regulator, TIMELESS, may serve as a molecular bridge between these two regulatory systems. Methods To assess the role of TIMELESS in tumorigenesis, we analyzed TIMELESS expression data from publically accessible online databases. A loss-of-function analysis was then performed using TIMELESS-targeting siRNA oligos followed by a whole-genome expression microarray and network analysis. We further tested the effect of TIMELESS down-regulation on cell proliferation rates of a breast and cervical cancer cell line, as suggested by the results of our network analysis. Results TIMELESS was found to be frequently overexpressed in different tumor types compared to normal controls. Elevated expression of TIMELESS was significantly associated with more advanced tumor stage and poorer breast cancer prognosis. We identified a cancer-relevant network of transcripts with altered expression following TIMELESS knockdown which contained many genes with known functions in cancer development and progression. Furthermore, we observed that TIMELESS knockdown significantly decreased cell proliferation rate. Conclusions Our results suggest a potential role for TIMELESS in tumorigenesis, which warrants further investigation of TIMELESS expression as a potential biomarker of cancer susceptibility and prognostic outcome. PMID:24161199

2013-01-01

33

Manipulation of Fgf and Bmp signaling in teleost fishes suggests potential pathways for the evolutionary origin of multicuspid teeth  

PubMed Central

Teeth with two or more cusps have arisen independently from an ancestral unicuspid condition in a variety of vertebrate lineages, including sharks, teleost fishes, amphibians, lizards, and mammals. One potential explanation for the repeated origins of multicuspid teeth is the existence of multiple adaptive pathways leading to them, as suggested by their different uses in these lineages. Another is that the addition of cusps required only minor changes in genetic pathways regulating tooth development. Here we provide support for the latter hypothesis by demonstrating that manipulation of the levels of Fibroblast growth factor (Fgf) or Bone morphogenetic protein (Bmp) signaling produces bicuspid teeth in the zebrafish (Danio rerio), a species lacking multicuspid teeth in its ancestry. The generality of these results for teleosts is suggested by the conversion of unicuspid pharyngeal teeth into bicuspid teeth by similar manipulations of the Mexican Tetra (Astyanax mexicanus). That these manipulations also produced supernumerary teeth in both species supports previous suggestions of similarities in the molecular control of tooth and cusp number. We conclude that despite their apparent complexity, the evolutionary origin of multicuspid teeth is positively constrained, likely requiring only slight modifications of a pre-existing mechanism for patterning the number and spacing of individual teeth. PMID:25098636

Jackman, William R; Davies, Shelby H; Lyons, David B; Stauder, Caitlin K; Denton-Schneider, Benjamin R; Jowdry, Andrea; Aigler, Sharon R; Vogel, Scott A; Stock, David W

2014-01-01

34

Constraints on lithospheric structure from satellite potential field data: Africa and Asia. Analysis and interpretation of MAGSAT anomalies over North Africa  

NASA Technical Reports Server (NTRS)

Crustal anomaly detection with MAGSAT data is frustrated by the inherent resolving power of the data and by contamination from the external and core fields. The quality of the data might be tested by modeling specific tectonic features which produce anomalies that fall within the proposed resolution and crustal amplitude capabilities of the MAGSAT fields. To test this hypothesis, the north African hotspots associated with Ahaggar, Tibestia and Darfur have been modeled as magnetic induction anomalies due solely to shallower depth to the Curie isotherm surface beneath these features. The MAGSAT data were reduced by subtracting the external and core fields to isolate the scalar and vertical component crustal signals. The predicted model magnetic signal arising from the surface topography of the uplift and the Curie isotherm surface was calculated at MAGSAT altitudes by the Fourier transform technique modified to allow for variable magnetization. In summary it is suggested that the region beneath Ahaggar is associated with a strong thermal anomaly and the predicted anomaly best fits the associated MAGSAT anomaly if the African plate is moving in a northeasterly direction.

Phillips, R. J.

1986-01-01

35

CT colonography for investigation of patients with symptoms potentially suggestive of colorectal cancer: a review of the UK SIGGAR trials  

PubMed Central

This paper argues for the use of CT colonography (CTC) to investigate patients with symptoms potentially suggestive of colorectal cancer. It describes the rationale for the UK Special Interest Group in Gastrointestinal and Abdominal Radiology (SIGGAR) randomised controlled trials that compared CTC with barium enema (BE) or colonoscopy for diagnosis of colorectal cancer or large polyps in symptomatic patients. Diagnostic outcomes from the trials are detailed for both intra- and extracolonic disease, along with psychological reactions of patients to the tests, and cost-effectiveness of the different diagnostic strategies. The author concludes that BE should be replaced by CTC immediately and that CTC is a sensitive, acceptable and equally cost-effective alternative to colonoscopy in patients in whom colonoscopy is contraindicated or undesirable. PMID:23568360

2013-01-01

36

1 Estimating aquifer hydraulic properties from the inversion of surface 2 Streaming Potential (SP) anomalies  

E-print Network

1 Estimating aquifer hydraulic properties from the inversion of surface 2 Streaming Potential (SP with the geometry of the water table. It follows that 11 SP measurements can be used to estimate aquifer hydraulic and found that we 14 are able to estimate the hydraulic conductivity and the depth 15 and the thickness

Sailhac, Pascal

37

Gravity Waves Generated by Sheared Three-Dimensional Potential Vorticity Anomalies  

E-print Network

, the disturbance is described ana- lytically using both an exact solution and a WKB approximation; the latter the temporal evolution of the GW field. Ana- lytical and numerical results are also used to establish, spontaneous adjustment is mixed with other mechanisms. For instance, large mountain GWs pro- duce potential

Plougonven, Riwal

38

Do U Txt? Event-Related Potentials to Semantic Anomalies in Standard and Texted English  

ERIC Educational Resources Information Center

Texted English is a hybrid, technology-based language derived from standard English modified to facilitate ease of communication via instant and text messaging. We compared semantic processing of texted and standard English sentences by recording event-related potentials in a classic semantic incongruity paradigm designed to elicit an N400 effect.…

Berger, Natalie I.; Coch, Donna

2010-01-01

39

Differences between discontinuous and continuous soft-core attractive potentials: The appearance of density anomaly  

Microsoft Academic Search

Soft-core attractive potentials can give rise to a phase diagram with three fluid phases at different densities (gas, low-density liquid and high-density liquid), separated by first order phase transition lines ending in critical points. Experiments show a phase diagram with these features for phosphorous and triphenyl phosphite. Liquid–liquid phase transition could be relevant for water, silica, liquid metals, colloids and

Giancarlo Franzese; Departament de Fisica Fonamental; Facultat de Fisica

2007-01-01

40

Pathogenic rare copy number variants in community-based schizophrenia suggest a potential role for clinical microarrays  

PubMed Central

Individually rare, large copy number variants (CNVs) contribute to genetic vulnerability for schizophrenia. Unresolved questions remain, however, regarding the anticipated yield of clinical microarray testing in schizophrenia. Using high-resolution genome-wide microarrays and rigorous methods, we investigated rare CNVs in a prospectively recruited community-based cohort of 459 unrelated adults with schizophrenia and estimated the minimum prevalence of clinically significant CNVs that would be detectable on a clinical microarray. A blinded review by two independent clinical cytogenetic laboratory directors of all large (>500 kb) rare CNVs in cases and well-matched controls showed that those deemed to be clinically significant were highly enriched in schizophrenia (16.4-fold increase, P < 0.0001). In a single community catchment area, the prevalence of individuals with these CNVs was 8.1%. Rare 1.7 Mb CNVs at 2q13 were found to be significantly associated with schizophrenia for the first time, compared with the prevalence in 23 838 population-based controls (42.9-fold increase, P = 0.0002). Additional novel findings that will facilitate the future clinical interpretation of smaller CNVs in schizophrenia include: (i) a greater proportion of individuals with two or more rare exonic CNVs >10 kb in size (1.5-fold increase, P = 0.0109) in schizophrenia; (ii) the systematic discovery of new candidate genes for schizophrenia; and, (iii) functional gene enrichment mapping highlighting a differential impact in schizophrenia of rare exonic deletions involving diverse functions, including neurodevelopmental and synaptic processes (4.7-fold increase, P = 0.0060). These findings suggest consideration of a potential role for clinical microarray testing in schizophrenia, as is now the suggested standard of care for related developmental disorders like autism. PMID:23813976

Costain, Gregory; Lionel, Anath C.; Merico, Daniele; Forsythe, Pamela; Russell, Kathryn; Lowther, Chelsea; Yuen, Tracy; Husted, Janice; Stavropoulos, Dimitri J.; Speevak, Marsha; Chow, Eva W.C.; Marshall, Christian R.; Scherer, Stephen W.; Bassett, Anne S.

2013-01-01

41

Unbalanced Activation of Glutathione Metabolic Pathways Suggests Potential Involvement in Plant Defense against the Gall Midge Mayetiola destructor in Wheat  

PubMed Central

Glutathione, ?-glutamylcysteinylglycine, exists abundantly in nearly all organisms. Glutathione participates in various physiological processes involved in redox reactions by serving as an electron donor/acceptor. We found that the abundance of total glutathione increased up to 60% in resistant wheat plants within 72?hours following attack by the gall midge Mayetiola destructor, the Hessian fly. The increase in total glutathione abundance, however, is coupled with an unbalanced activation of glutathione metabolic pathways. The activity and transcript abundance of glutathione peroxidases, which convert reduced glutathione (GSH) to oxidized glutathione (GSSG), increased in infested resistant plants. However, the enzymatic activity and transcript abundance of glutathione reductases, which convert GSSG back to GSH, did not change. This unbalanced regulation of the glutathione oxidation/reduction cycle indicates the existence of an alternative pathway to regenerate GSH from GSSG to maintain a stable GSSG/GSH ratio. Our data suggest the possibility that GSSG is transported from cytosol to apoplast to serve as an oxidant for class III peroxidases to generate reactive oxygen species for plant defense against Hessian fly larvae. Our results provide a foundation for elucidating the molecular processes involved in glutathione-mediated plant resistance to Hessian fly and potentially other pests as well. PMID:25627558

Liu, Xuming; Zhang, Shize; Whitworth, R. Jeff; Stuart, Jeffrey J.; Chen, Ming-Shun

2015-01-01

42

Identification of Plasmopara viticola genes potentially involved in pathogenesis on grapevine suggests new similarities between oomycetes and true fungi.  

PubMed

Plant diseases caused by fungi and oomycetes result in significant economic losses every year. Although phylogenetically distant, these organisms share many common features during infection. We identified genes in the oomycete Plasmopara viticola that are potentially involved in pathogenesis in grapevine by using fungal databases and degenerate primers. Fragments of P. viticola genes encoding NADH-ubiquinone oxidoreductase (PvNuo), laccase (PvLac), and invertase (PvInv) were obtained. PvNuo was overexpressed at 2 days postinoculation (dpi), during the development of the first hyphal structures and haustoria. PvLac was overexpressed at 5 dpi when genes related to pterostilbene biosynthesis were induced in grapevine. Transcript level for PvInv increased between 1 and 4 dpi before reaching a plateau. These results might suggest a finely tuned strategy of infection depending on nutrition and plant response. Phylogenetic analyses of PvNuo showed that P. viticola clustered with other oomycetes and was associated with brown algae and diatoms, forming a typical Straminipila clade. Based on the comparison of available sequences for laccases and invertases, the group formed by P. viticola and other oomycetes tended to be more closely related to Opisthokonta than to Straminipila. Convergent evolution or horizontal gene transfer could explain the presence of fungus-like genes in P. viticola. PMID:23634808

Luis, P; Gauthier, A; Trouvelot, S; Poinssot, B; Frettinger, P

2013-10-01

43

Mapping Stratigraphy and Anomalies in Iron-Rich Volcanoclastics Using Ground-Penetrating Radar: Potential for Subsurface Exploration on Mars  

Microsoft Academic Search

Ground-penetrating radar (GPR) studies conducted in iron-rich volcanoclastics can yield valuable information for interpreting the subsurface stratigraphy resulting from lava flows and intervening unconsolidated volcanic and sedimentary deposits with different compositions and ages. GPR is also valuable for mapping subsurface anomalies and structures, such as rifts and lava tubes. We performed a geophysical field survey in Craters of the Moon

E. Heggy; S. Clifford; S. Khan; J. Fernandez; E. Wiggs; S. L. Gonzalez; D. Wyrick; R. Grimm; C. Dinwiddie; A. Pommerol

2004-01-01

44

Developmental Expression of Smoc1 and Smoc2 Suggests Potential Roles in Fetal Gonad and Reproductive Tract Differentiation  

PubMed Central

SMOC1 and SMOC2 are matricellular proteins thought to influence growth factor signaling, migration, proliferation and angiogenesis. We examined the expression and regulation of Smoc1 and Smoc2 in fetal gonad/mesonephros complexes to discover possible roles for these genes in gonad and mesonephros development. Smoc1 was upregulated at ~E10.75 in a center-to-poles wave in pre-Sertoli and pre-granulosa cells and its expression was greatly reduced in Wt1, Sf1 and Fog2 mutants. After E13.5, Smoc1 was downregulated in an anterior-to-posterior wave in granulosa cells but persisted in Sertoli cells, suggesting a sexually dimorphic requirement in supporting cell lineage differentiation. Smoc2 was expressed in Leydig cells, mesonephroi, and Wnt4 mutant ovaries, but not wildtype ovaries. Using organ culture, we determined that Smoc2 expression was dependent on Hedgehog signaling in testes, mesonephroi, and kidneys. Overall, these results demonstrate that SMOC1 and SMOC2 may mediate intercellular signaling and cell type-specific differentiation during gonad and reproductive tract development. PMID:19842175

Pazin, Dorothy E.; Albrecht, Kenneth H.

2010-01-01

45

Genomic alterations in biliary atresia suggest region of potential disease susceptibility in 2q37.3.  

PubMed

Biliary atresia (BA) is a progressive, idiopathic obliteration of the extrahepatic biliary system occurring exclusively in the neonatal period. It is the most common disease leading to liver transplantation in children. The etiology of BA is unknown, although infectious, immune and genetic causes have been suggested. Although the recurrence of BA in families is not common, there are more than 30 multiplex families reported and an underlying genetic susceptibility has been hypothesized. We screened a cohort of 35 BA patients for genomic alterations that might confer susceptibility to BA. DNA was genotyped on the Illumina Human Hap 550 Beadchip platform, which analyzes over 550,000 single nucleotide polymorphisms (SNPs) for genomic deletions and duplications. Areas of increased and decreased copy number were compared to those found in control populations. To identify regions that could serve as susceptibility factors for BA, we searched for regions that were found in BA patients, but not in controls. We identified two unrelated BA patients with overlapping heterozygous deletions of 2q37.3. Patient 1 had a 1.76 Mb (280 SNP), heterozygous deletion containing 30 genes. Patient 2 had a 5.87 Mb (1,346 SNP) heterozygous deletion containing 55 genes. The overlapping 1.76 Mb deletion on chromosome 2q37.3 from 240,936,900 to 242,692,820 constitutes the critical region and the genes within this region could be candidates for susceptibility to BA. PMID:20358598

Leyva-Vega, Melissa; Gerfen, Jennifer; Thiel, Brian D; Jurkiewicz, Dorota; Rand, Elizabeth B; Pawlowska, Joanna; Kaminska, Diana; Russo, Pierre; Gai, Xiaowu; Krantz, Ian D; Kamath, Binita M; Hakonarson, Hakon; Haber, Barbara A; Spinner, Nancy B

2010-04-01

46

Network analysis suggests a potentially 'evil' alliance of opportunistic pathogens inhibited by a cooperative network in human milk bacterial communities.  

PubMed

The critical importance of human milk to infants and even human civilization has been well established. Yet our understanding of the milk microbiome has been limited to cataloguing OTUs and computation of community diversity. To the best of our knowledge, there has been no report on the bacterial interactions within the milk microbiome. To bridge this gap, we reconstructed a milk bacterial community network based on Hunt et al. Our analysis revealed that the milk microbiome network consists of two disconnected sub-networks. One sub-network is a fully connected complete graph consisting of seven genera as nodes and all of its pair-wise interactions among the bacteria are facilitative or cooperative. In contrast, the interactions in the other sub-network of eight nodes are mixed but dominantly cooperative. Somewhat surprisingly, the only 'non-cooperative' nodes in the second sub-network are mutually cooperative Staphylococcus and Corynebacterium that include some opportunistic pathogens. This potentially 'evil' alliance between Staphylococcus and Corynebacterium could be inhibited by the remaining nodes that cooperate with one another in the second sub-network. We postulate that the 'confrontation' between the 'evil' alliance and 'benign' alliance and the shifting balance between them may be responsible for dysbiosis of the milk microbiome that permits mastitis. PMID:25651890

Sam Ma, Zhanshan; Guan, Qiong; Ye, Chengxi; Zhang, Chengchen; Foster, James A; Forney, Larry J

2015-01-01

47

Network analysis suggests a potentially ‘evil' alliance of opportunistic pathogens inhibited by a cooperative network in human milk bacterial communities  

PubMed Central

The critical importance of human milk to infants and even human civilization has been well established. Yet our understanding of the milk microbiome has been limited to cataloguing OTUs and computation of community diversity. To the best of our knowledge, there has been no report on the bacterial interactions within the milk microbiome. To bridge this gap, we reconstructed a milk bacterial community network based on Hunt et al. Our analysis revealed that the milk microbiome network consists of two disconnected sub-networks. One sub-network is a fully connected complete graph consisting of seven genera as nodes and all of its pair-wise interactions among the bacteria are facilitative or cooperative. In contrast, the interactions in the other sub-network of eight nodes are mixed but dominantly cooperative. Somewhat surprisingly, the only ‘non-cooperative' nodes in the second sub-network are mutually cooperative Staphylococcus and Corynebacterium that include some opportunistic pathogens. This potentially ‘evil' alliance between Staphylococcus and Corynebacterium could be inhibited by the remaining nodes that cooperate with one another in the second sub-network. We postulate that the ‘confrontation' between the ‘evil' alliance and ‘benign' alliance and the shifting balance between them may be responsible for dysbiosis of the milk microbiome that permits mastitis. PMID:25651890

(Sam) Ma, Zhanshan; Guan, Qiong; Ye, Chengxi; Zhang, Chengchen; Foster, James A.; Forney, Larry J.

2015-01-01

48

Microtopography of the eye surface of the crab Carcinus maenas: an atomic force microscope study suggesting a possible antifouling potential  

PubMed Central

Marine biofouling causes problems for technologies based on the sea, including ships, power plants and marine sensors. Several antifouling techniques have been applied to marine sensors, but most of these methodologies are environmentally unfriendly or ineffective. Bioinspiration, seeking guidance from natural solutions, is a promising approach to antifouling. Here, the eye of the green crab Carcinus maenas was regarded as a marine sensor model and its surface characterized by means of atomic force microscopy. Engineered surface micro- and nanotopography is a new mechanism found to limit biofouling, promising an effective solution with much reduced environmental impact. Besides giving a new insight into the morphology of C. maenas eye and its characterization, our study indicates that the eye surface probably has antifouling/fouling-release potential. Furthermore, the topographical features of the surface may influence the wettability properties of the structure and its interaction with organic molecules. Results indicate that the eye surface micro- and nanotopography may lead to bioinspired solutions to antifouling protection. PMID:23635491

Greco, G.; Lanero, T. Svaldo; Torrassa, S.; Young, R.; Vassalli, M.; Cavaliere, A.; Rolandi, R.; Pelucchi, E.; Faimali, M.; Davenport, J.

2013-01-01

49

Combined analyses of kinship and FST suggest potential drivers of chaotic genetic patchiness in high gene-flow populations.  

PubMed

We combine kinship estimates with traditional F-statistics to explain contemporary drivers of population genetic differentiation despite high gene flow. We investigate range-wide population genetic structure of the California spiny (or red rock) lobster (Panulirus interruptus) and find slight, but significant global population differentiation in mtDNA (?ST = 0.006, P = 0.001; D(est_Chao) = 0.025) and seven nuclear microsatellites (F(ST) = 0.004, P < 0.001; D(est_Chao) = 0.03), despite the species' 240- to 330-day pelagic larval duration. Significant population structure does not correlate with distance between sampling locations, and pairwise FST between adjacent sites often exceeds that among geographically distant locations. This result would typically be interpreted as unexplainable, chaotic genetic patchiness. However, kinship levels differ significantly among sites (pseudo-F(16,988) = 1.39, P = 0.001), and ten of 17 sample sites have significantly greater numbers of kin than expected by chance (P < 0.05). Moreover, a higher proportion of kin within sites strongly correlates with greater genetic differentiation among sites (D(est_Chao), R(2) = 0.66, P < 0.005). Sites with elevated mean kinship were geographically proximate to regions of high upwelling intensity (R(2) = 0.41, P = 0.0009). These results indicate that P. interruptus does not maintain a single homogenous population, despite extreme dispersal potential. Instead, these lobsters appear to either have substantial localized recruitment or maintain planktonic larval cohesiveness whereby siblings more likely settle together than disperse across sites. More broadly, our results contribute to a growing number of studies showing that low F(ST) and high family structure across populations can coexist, illuminating the foundations of cryptic genetic patterns and the nature of marine dispersal. PMID:23802550

Iacchei, Matthew; Ben-Horin, Tal; Selkoe, Kimberly A; Bird, Christopher E; García-Rodríguez, Francisco J; Toonen, Robert J

2013-07-01

50

Combined analyses of kinship and FST suggest potential drivers of chaotic genetic patchiness in high gene-flow populations  

PubMed Central

We combine kinship estimates with traditional F-statistics to explain contemporary drivers of population genetic differentiation despite high gene flow. We investigate range-wide population genetic structure of the California spiny (or red rock) lobster (Panulirus interruptus) and find slight, but significant global population differentiation in mtDNA (?ST = 0.006, P = 0.001; Dest_Chao = 0.025) and seven nuclear microsatellites (FST = 0.004, P < 0.001; Dest_Chao = 0.03), despite the species’ 240- to 330-day pelagic larval duration. Significant population structure does not correlate with distance between sampling locations, and pairwise FST between adjacent sites often exceeds that among geographically distant locations. This result would typically be interpreted as unexplainable, chaotic genetic patchiness. However, kinship levels differ significantly among sites (pseudo-F16,988 = 1.39, P = 0.001), and ten of 17 sample sites have significantly greater numbers of kin than expected by chance (P < 0.05). Moreover, a higher proportion of kin within sites strongly correlates with greater genetic differentiation among sites (Dest_Chao, R2 = 0.66, P < 0.005). Sites with elevated mean kinship were geographically proximate to regions of high upwelling intensity (R2 = 0.41, P = 0.0009). These results indicate that P. interruptus does not maintain a single homogenous population, despite extreme dispersal potential. Instead, these lobsters appear to either have substantial localized recruitment or maintain planktonic larval cohesiveness whereby siblings more likely settle together than disperse across sites. More broadly, our results contribute to a growing number of studies showing that low FST and high family structure across populations can coexist, illuminating the foundations of cryptic genetic patterns and the nature of marine dispersal. PMID:23802550

Iacchei, Matthew; Ben-Horin, Tal; Selkoe, Kimberly A; Bird, Christopher E; García-Rodríguez, Francisco J; Toonen, Robert J

2013-01-01

51

Bangui Anomaly  

NASA Technical Reports Server (NTRS)

Bangui anomaly is the name given to one of the Earth s largest crustal magnetic anomalies and the largest over the African continent. It covers two-thirds of the Central African Republic and therefore the name derives from the capitol city-Bangui that is also near the center of this feature. From surface magnetic survey data Godivier and Le Donche (1962) were the first to describe this anomaly. Subsequently high-altitude world magnetic surveying by the U.S. Naval Oceanographic Office (Project Magnet) recorded a greater than 1000 nT dipolar, peak-to-trough anomaly with the major portion being negative (figure 1). Satellite observations (Cosmos 49) were first reported in 1964, these revealed a 40nT anomaly at 350 km altitude. Subsequently the higher altitude (417-499km) POGO (Polar Orbiting Geomagnetic Observatory) satellite data recorded peak-to-trough anomalies of 20 nT these data were added to Cosmos 49 measurements by Regan et al. (1975) for a regional satellite altitude map. In October 1979, with the launch of Magsat, a satellite designed to measure crustal magnetic anomalies, a more uniform satellite altitude magnetic map was obtained. These data, computed at 375 km altitude recorded a -22 nT anomaly (figure 2). This elliptically shaped anomaly is approximately 760 by 1000 km and is centered at 6%, 18%. The Bangui anomaly is composed of three segments; there are two positive anomalies lobes north and south of a large central negative field. This displays the classic pattern of a magnetic anomalous body being magnetized by induction in a zero inclination field. This is not surprising since the magnetic equator passes near the center of this body.

Taylor, Patrick T.

2004-01-01

52

Anomaly Holography  

E-print Network

We consider, in the effective field theory context, anomalies of gauge field theories on a slice of a five-dimensional, Anti-de Sitter geometry and their four-dimensional, holographic duals. A consistent effective field theory description can always be found, notwithstanding the presence of the anomalies and without modifying the degrees of freedom of the theory. If anomalies do not vanish, the d=4 theory contains additional pseudoscalar states, which are either present in the low-energy theory as physical, light states, or are eaten by (would-be massless) gauge bosons. We show that the pseudoscalars ensure that global anomalies of the four-dimensional dual satisfy the 't Hooft matching condition and comment on the relevance for warped models of electroweak symmetry breaking.

Ben Gripaios; Stephen M. West

2007-04-30

53

Geologic Insights and Suggestions on Mineral Potential Based on Analyses of Geophysical Data of the Southern Toquima Range, Nye County, Nevada  

USGS Publications Warehouse

Aeromagnetic and gravity data provide confirmation of major structural and lithologic units in the southern Toquima Range, Nevada. These units include Cretaceous granite plutons and Tertiary calderas. In addition, the geophysical maps pinpoint numerous faults and lesser intrusions, and they suggest locations of several inferred subsurface intrusions. They also corroborate a system of northwesterly and northeasterly conjugate structures that probably are fundamental to the structural framework of the Toquima Range. A combination of geophysical, geochemical, and geologic data available for the widely mineralized and productive area suggests additional mineral resource potential, especially in and (or) adjacent to the Round Mountain, Jefferson, Manhattan, and Belmont mining districts. Also, evidence for mineral potential exists for areas near the Flower mercury mine south of Mount Jefferson caldera, and in the Bald Mountain Canyon belt of gold-quartz veins in the Manhattan caldera. A few other areas also show potential for mineral resources. The various geologic environments indicated within the map area suggest base- and precious-metal potential in porphyry deposits as well as in quartz-vein and skarn deposits associated with intrusive stocks.

Shawe, D.R.; Kucks, R.P.; Hildenbrand, T.G.

2004-01-01

54

Complex lymphatic anomalies.  

PubMed

Complex lymphatic anomalies include several diagnoses with overlapping patterns of clinical symptoms, anatomic location, imaging features, hematologic alterations, and complications. Lymphatic malformations likely arise through anomalous embryogenesis of the lymphatic system. Analysis of clinical, imaging, histologic, and hematologic features is often needed to reach a diagnosis. Aspiration of fluid collections can readily define fluid as chylous or not. The presence of chyle indicates dysfunction at the mesenteric or retroperitoneal level or above the cisterna chyli due to reflux. The imaging patterns of generalized lymphatic anomaly (GLA) and Gorham-Stout disease have been segregated with distinctive bone lesions and peri-osseous features. More aggressive histology (spindled lymphatic endothelial cells), clinical progression, hemorrhage, or moderate hematologic changes should raise suspicion for kaposiform lymphangiomatosis. Biopsy may be needed for diagnosis, though avoidance of rib biopsy is advised to prevent iatrogenic chronic pleural effusion. Lymphangiography can visualize the anatomy and function of the lymphatic system and may identify dysfunction of the thoracic duct in central conducting lymphatic anomalies. Local control and symptom relief are targeted by resection, laser therapy, and sclerotherapy. Emerging data suggest a role for medical therapies for complications of complex lymphatic anomalies. Outcomes include recurrent effusion, infection, pain, fracture, mortality, and rarely, malignancy. Complex lymphatic anomalies present significant diagnostic and therapeutic challenges. Results from a phase 2 study of sirolimus in these and other conditions are expected in 2014. Improved characterization of natural history, predictors of poor outcomes, responses to therapy, and further clinical trials are needed for complex lymphatic anomalies. PMID:25241096

Trenor, Cameron C; Chaudry, Gulraiz

2014-08-01

55

Identifying Anomalies in Gravitational Lens Time Delays  

NASA Astrophysics Data System (ADS)

Gravitational lensing has become a powerful probe of cold dark matter substructure. Earlier work using anomalous flux ratios in four-image quasar lenses has shown that lensing is sensitive to substructure which raises the exciting prospect of constraining the mass function and spatial distribution of dark matter satellites in galaxies. We examine the ability of gravitational lens time delays to reveal complex structure in lens potentials. We use Monte Carlo simulations to determine the range of time delays that can be produced by realistic smooth lens models consisting of isothermal ellipsoid galaxies with tidal shear. We can then identify outliers as "time-delay anomalies." We find evidence for anomalies in close image pairs in the cusp lenses RX J1131-1231 and B1422+231. The anomalies in RX J1131-1231 provide strong evidence for substructure in the lens potential, while at this point the apparent anomalies in B1422+231 mainly indicate that the time delay measurements need to be improved. We also find evidence for time-delay anomalies in larger-separation image pairs in four additional lenses. We suggest that these anomalies are caused by some combination of substructure and a complex lens environment. Our work argues for a large sample of strong lenses with precisely-measured time delays. The first of these objectives will be readily achievable as the next generation of optical and radio telescopes come online, while the second will require a dedicated one-meter class space-based observatory. Meeting these goals will make it possible to examine the properties of dark matter on sub-galactic scales, which is essential for distinguishing among the various dark matter candidates from particle physics. Part of this work was funded by NSF grant AST-0747311. ABC is currently supported by an appointment to the NASA Postdoctoral Program at the Jet Propulsion Laboratory, administered by Oak Ridge Associated Universities through a contract with NASA.

Congdon, Arthur B.; Keeton, C. R.; Nordgren, C. E.

2009-05-01

56

Potential gradients produced by pore-space heterogeneities: Application to isothermal frost damage and submarine hydrate anomalies  

E-print Network

Potential gradients produced by pore-space heterogeneities: Application to isothermal frost damage the supply of constituents through a fluid phase. With frost damage, the gradi- ents in chemical potential for constituent supply. We illustrate the consequences and character of isothermal frost damage using the results

Rempel, Alan W.

57

DOWN'S ANOMALY.  

ERIC Educational Resources Information Center

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)…

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

58

Streaming potential and permeability of saturated sandstones under triaxial stress: Consequences for electrotelluric anomalies prior to earthquakes  

Microsoft Academic Search

The streaming potential, due to fluid circulation in rock, was measured on saturated sediments (Fontainebleau sandstones). The electrokinetic coupling coefficient, which is the ratio of the streaming potential and the excess pore pressure, is proportional to the fluid resistivity. Additionally, for a fluid conductivity of 10-3 S\\/m, the electrokinetic coupling coefficient varies from 10 to 6642 mV\\/0.1 MPa for sample

Laurence Jouniaux; Jean-Pierre Pozzi

1995-01-01

59

amoA Gene Abundances and Nitrification Potential Rates Suggest that Benthic Ammonia-Oxidizing Bacteria and Not Archaea Dominate N Cycling in the Colne Estuary, United Kingdom  

PubMed Central

Nitrification, mediated by ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA), is important in global nitrogen cycling. In estuaries where gradients of salinity and ammonia concentrations occur, there may be differential selections for ammonia-oxidizer populations. The aim of this study was to examine the activity, abundance, and diversity of AOA and AOB in surface oxic sediments of a highly nutrified estuary that exhibits gradients of salinity and ammonium. AOB and AOA communities were investigated by measuring ammonia monooxygenase (amoA) gene abundance and nitrification potentials both spatially and temporally. Nitrification potentials differed along the estuary and over time, with the greatest nitrification potentials occurring mid-estuary (8.2 ?mol N grams dry weight [gdw]?1 day?1 in June, increasing to 37.4 ?mol N gdw?1 day?1 in January). At the estuary head, the nitrification potential was 4.3 ?mol N gdw?1 day?1 in June, increasing to 11.7 ?mol N gdw?1 day?1 in January. At the estuary head and mouth, nitrification potentials fluctuated throughout the year. AOB amoA gene abundances were significantly greater (by 100-fold) than those of AOA both spatially and temporally. Nitrosomonas spp. were detected along the estuary by denaturing gradient gel electrophoresis (DGGE) band sequence analysis. In conclusion, AOB dominated over AOA in the estuarine sediments, with the ratio of AOB/AOA amoA gene abundance increasing from the upper (freshwater) to lower (marine) regions of the Colne estuary. These findings suggest that in this nutrified estuary, AOB (possibly Nitrosomonas spp.) were of major significance in nitrification. PMID:25326303

Li, Jialin; Nedwell, David B.; Beddow, Jessica; Dumbrell, Alex J.; McKew, Boyd A.; Thorpe, Emma L.

2014-01-01

60

amoA Gene Abundances and Nitrification Potential Rates Suggest that Benthic Ammonia-Oxidizing Bacteria and Not Archaea Dominate N Cycling in the Colne Estuary, United Kingdom.  

PubMed

Nitrification, mediated by ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA), is important in global nitrogen cycling. In estuaries where gradients of salinity and ammonia concentrations occur, there may be differential selections for ammonia-oxidizer populations. The aim of this study was to examine the activity, abundance, and diversity of AOA and AOB in surface oxic sediments of a highly nutrified estuary that exhibits gradients of salinity and ammonium. AOB and AOA communities were investigated by measuring ammonia monooxygenase (amoA) gene abundance and nitrification potentials both spatially and temporally. Nitrification potentials differed along the estuary and over time, with the greatest nitrification potentials occurring mid-estuary (8.2 ?mol N grams dry weight [gdw](-1) day(-1) in June, increasing to 37.4 ?mol N gdw(-1) day(-1) in January). At the estuary head, the nitrification potential was 4.3 ?mol N gdw(-1) day(-1) in June, increasing to 11.7 ?mol N gdw(-1) day(-1) in January. At the estuary head and mouth, nitrification potentials fluctuated throughout the year. AOB amoA gene abundances were significantly greater (by 100-fold) than those of AOA both spatially and temporally. Nitrosomonas spp. were detected along the estuary by denaturing gradient gel electrophoresis (DGGE) band sequence analysis. In conclusion, AOB dominated over AOA in the estuarine sediments, with the ratio of AOB/AOA amoA gene abundance increasing from the upper (freshwater) to lower (marine) regions of the Colne estuary. These findings suggest that in this nutrified estuary, AOB (possibly Nitrosomonas spp.) were of major significance in nitrification. PMID:25326303

Li, Jialin; Nedwell, David B; Beddow, Jessica; Dumbrell, Alex J; McKew, Boyd A; Thorpe, Emma L; Whitby, Corinne

2015-01-01

61

Functional characterization of a competitive peptide antagonist of p65 in human macrophage-like cells suggests therapeutic potential for chronic inflammation  

PubMed Central

Glucocorticoid-induced leucine zipper (GILZ) is a glucocorticoid responsive protein that links the nuclear factor-kappa B (NF?B) and the glucocorticoid signaling pathways. Functional and binding studies suggest that the proline-rich region at the carboxy terminus of GILZ binds the p65 subunit of NF?B and suppresses the immunoinflammatory response. A widely-used strategy in the discovery of peptide drugs involves exploitation of the complementary surfaces of naturally occurring binding partners. Previously, we observed that a synthetic peptide (GILZ-P) derived from the proline-rich region of GILZ bound activated p65 and ameliorated experimental encephalomyelitis. Here we characterize the secondary structure of GILZ-P by circular dichroic analysis. GILZ-P adopts an extended polyproline type II helical conformation consistent with the structural conformation commonly observed in interfaces of transient intermolecular interactions. To determine the potential application of GILZ-P in humans, we evaluated the toxicity and efficacy of the peptide drug in mature human macrophage-like THP-1 cells. Treatment with GILZ-P at a wide range of concentrations commonly used for peptide drugs was nontoxic as determined by cell viability and apoptosis assays. Functionally, GILZ-P suppressed proliferation and glutamate secretion by activated macrophages by inhibiting nuclear translocation of p65. Collectively, our data suggest that the GILZ-P has therapeutic potential in chronic CNS diseases where persistent inflammation leads to neurodegeneration such as multiple sclerosis and Alzheimer’s disease. PMID:25584020

Srinivasan, Mythily; Blackburn, Corinne; Lahiri, Debomoy K

2014-01-01

62

Anomaly Transform method for initializing climate forecas.  

NASA Astrophysics Data System (ADS)

A new approach, an Anomaly Transform method (AT) using a physics based metric, is developed to initialize decadal climate hindcast within the German climate prediction MiKlip project. The method starts from balanced anomaly structures in space and time and between variables derived from control runs and applies an orthogalization to these. Two physics based metric are used to set up the eigen problem (1) the weighted total energy with its zonal, meridional kinetic and available potential energy terms having equal contributions, and (2) the weighted ocean heat content in which a disturbance is applied only to the initial temperature fields. The choice of a reference state defining the anomalies and the selected sequence of anomalies, once on a seasonal timescales and second on an interannual timescales, project a-priori only the slow modes of the ocean physical processes, such that the disturbances grow mainly in the Western Boundary Currents, in the ACC and ENSO regions. An additional set of initial conditions was designed to fit in a least square sense anomalies from the GECCO-2 ocean reanalysis. These sets of AT initial conditions and the MPIOM-ESM coupled model in T63L47/GR15 resolution were used for ensemble experiments and a retrospective forecast. The weighted total energy norm is used to monitor the amplitudes and rates of the fastest growing error modes. The results showed minor dependence of the instability growth on the selected metric but considerable change due to the rescaling coefficients magnitude on the perturbation amplitude. In contrary to similar atmospheric applications, we find an energy conversion from kinetic to available potential energy, which suggests different source of uncertainties mainly associated with changes in density fields.

Romanova, Vanya; Hense, Andreas

2014-05-01

63

Mass Anomalies on Ganymede  

NASA Technical Reports Server (NTRS)

Radio Doppler data from two Ganymede encounters (G1 and G2) on the first two orbits in the Galileo mission have been analyzed previously for gravity information . For a satellite in hydrostatic equilibrium, its gravitational field can be modeled adequately by a truncated spherical harmonic series of degree two. However, a fourth degree field is required in order to fit the second Galileo flyby (G2). This need for a higher degree field strongly suggests that Ganymede s gravitational field is perturbed by a gravity anomaly near the G2 closest approach point (79.29 latitude, 123.68 west longitude). In fact, a plot of the Doppler residuals , after removal of the best-fit model for the zero degree term (GM) and the second degree moments (J2 and C22), suggests that if an anomaly exists, it is located downtrack of the closest approach point, closer to the equator.

Schubert, G.; Anderson, J. D.; Jacobson, R. A.; Lau, E. L.; Moore, W. B.; Palguta, J.

2004-01-01

64

Flux Ratio Anomalies: Micro- and Milli-lensing  

E-print Network

Simple models for lensing potentials that successfully reproduce the positions of quadruple images to high accuracy fail abysmally in reproducing the flux ratios of the multiple images, suggesting the presence of small scale structure within the lensing galaxies. It has been argued that the flux ratio anomalies observed at radio wavelengths signal the presence of CDM mini-halos. We argue that at least some of the anomalies observed at optical wavelengths result from micro-lensing by stars. This model succeeds in explaining observed asymmetry between minima and saddle-points of the light travel time only if a substantial fraction of the projected mass is in a smooth, dark component.

Paul L. Schechter

2003-04-26

65

Geochemical anomalies from bottom ash in a road construction--comparison of the leaching potential between an ash road and the surroundings.  

PubMed

A study was performed between June 2001 and December 2004 with the primary objective of assessing long-term leaching from municipal solid waste incineration bottom ash in a test road construction in relation to a reference road made up of conventional materials and the natural geochemical conditions in the surroundings. The metal leaching from the test road and the reference road was compared with the natural weathering in the regional surroundings for three time scales: 16, 80 and 1000 years. The results show that Cu and Zn cause a geochemical anomaly from the test road compared with the surroundings. The leaching of Cu from the test road is initially high but will decline with time and will in the long term be exceeded by natural weathering. Zn on the other hand has low initial leaching, which will increase with time and will in the long term exceed that of the test road and the surroundings by a factor of 100-300. For the other metals studied, Al, Na, K and Mg, there is only very limited leaching over time and the potential accumulation will not exceed the background values in a 1000 years. PMID:17306524

Lind, Bo B; Norrman, Jenny; Larsson, Lennart B; Ohlsson, Sten-Ake; Bristav, Henrik

2008-01-01

66

Integral formulas for computing a third-order gravitational tensor from volumetric mass density, disturbing gravitational potential, gravity anomaly and gravity disturbance  

NASA Astrophysics Data System (ADS)

A new mathematical model for evaluation of the third-order (disturbing) gravitational tensor is formulated in this article. Firstly, we construct corresponding differential operators for the components of the third-order (disturbing) gravitational tensor in a spherical local north-oriented frame. We show that the differential operators may efficiently be decomposed into an azimuthal and an isotropic part. The differential operators are even more simplified for a certain class of isotropic kernels. Secondly, the differential operators are applied to the well-known integrals of Newton, Abel-Poisson, Pizzetti and Hotine. In this way, 40 new integral formulas are derived. The new integral formulas allow for evaluation of the components of the third-order (disturbing) gravitational tensor from density distribution, disturbing gravitational potential, gravity anomalies and gravity disturbances. Thirdly, we investigate the behaviour of the corresponding integral kernels in the spatial domain. The new mathematical formulas extend the theoretical apparatus of geodesy, i.e. the well-known Meissl scheme, and reveal important properties of the third-order gravitational tensor. They may be exploited in geophysical studies, continuation of gravitational field quantities and analysing the gradiometric-geodynamic boundary value problem.

Šprlák, Michal; Novák, Pavel

2015-02-01

67

Life cycles of persistent anomalies. II - The development of persistent negative height anomalies over the North Pacific Ocean  

NASA Technical Reports Server (NTRS)

Consideration is given to the potential sources for the development of cases defined by strong and persistent negative height anomalies over the central North Pacific. The analyses of Dole (1986) are extended by providing a more complete synoptic description of the developments and additional diagnostic analysis to identify dynamical mechanisms responsible for the developments. The synoptic characteristics of the developments are reviewed and the barotropic and baroclinic processes of the developments are analyzed. The reproducibility and representativeness of the results are examined. The observed characteristics suggest that the large-scale flow anomalies develop as a result of an instability of three-dimensional wintertime mean flow.

Dole, Randall M.; Black, Robert X.

1990-01-01

68

HDFx: a novel biologic immunomodulator accelerates wound healing and is suggestive of unique regenerative powers: potential implications for the warfighter and disaster victims.  

PubMed

Recently, we reported on the discovery of a new, conserved biologic protein (35-40 KDa), termed HDFx, that protects rats, guinea-pigs, mice, and rabbits against lethal hemorrhage, endotoxins, intestinal ischemic-shock, and traumatic injuries. It was found to stimulate several arms of the immune system. The present report demonstrates, for the first time, that HDFx accelerates wound healing in two different models (excision wound model; and incision wound model) in rats. The results shown, herein, indicate that HDFx produces greater rates of wound contraction, greater tensile strength, and more rapid healing than controls. Our new data also show that this biologic increases hydroxyproline content of granulation tissue coupled with a reduction in superoxide dismutase (SOD). In addition, we show that HDFx increases the levels of serum ascorbic acid and stimulates the mononuclear cells of the reticuloendothelial system (RES). Overall, these data suggest that HDFx may possess unique regenerative powers. We, thus, believe that HDFx can be of great potential use in diverse types of wounds which, otherwise, could result in difficult to treat infections and thus prevent sepsis and loss of body parts from amputations. PMID:22993647

Altura, Burton M; Carella, Anthony; Gebrewold, Asefa

2012-01-01

69

HDFx: a novel biologic immunomodulator accelerates wound healing and is suggestive of unique regenerative powers: potential implications for the warfighter and disaster victims  

PubMed Central

Recently, we reported on the discovery of a new, conserved biologic protein (35-40 KDa), termed HDFx, that protects rats, guinea-pigs, mice, and rabbits against lethal hemorrhage, endotoxins, intestinal ischemic-shock, and traumatic injuries. It was found to stimulate several arms of the immune system. The present report demonstrates, for the first time, that HDFx accelerates wound healing in two different models (excision wound model; and incision wound model) in rats. The results shown, herein, indicate that HDFx produces greater rates of wound contraction, greater tensile strength, and more rapid healing than controls. Our new data also show that this biologic increases hydroxyproline content of granulation tissue coupled with a reduction in superoxide dismutase (SOD). In addition, we show that HDFx increases the levels of serum ascorbic acid and stimulates the mononuclear cells of the reticuloendothelial system (RES). Overall, these data suggest that HDFx may possess unique regenerative powers. We, thus, believe that HDFx can be of great potential use in diverse types of wounds which, otherwise, could result in difficult to treat infections and thus prevent sepsis and loss of body parts from amputations. PMID:22993647

Altura, Burton M; Carella, Anthony; Gebrewold, Asefa

2012-01-01

70

Dosing of adult pigeons with as little as one #9 lead pellet caused severe ?-ALAD depression, suggesting potential adverse effects in wild populations.  

PubMed

Avian wildlife species commonly ingest lead (Pb) spent shot or bullet fragments as grit or mistakenly as food. In previous studies in our laboratory and others, the toxicity varied based on the diet as well as type and quantity of Pb ingested. In the current study, domestic pigeons were gavaged with 1, 2, or 3 Pb pellets and then followed with weekly radiographs and blood physiologic endpoints for 28 days. Pellet retention decreased by roughly 50 % per week as pellets were either absorbed or excreted, except for week 4 where pellet number no longer was diminished. Size of retained pellets visually decreased over retention time. Birds dosed with a single #9 pellet showed mean blood Pb levels over 80 times higher than those of the controls, verifying Pb pellet absorption from the gut. A single Pb pellet also reduced plasma ?-aminolevulinic acid dehydratase (?-ALAD) activity by over 80 % compared to controls, suggesting the potential for population injury in Pb pellet-exposed pigeons. PMID:22903291

Holladay, Jeremy P; Nisanian, Mandy; Williams, Susan; Tuckfield, R Cary; Kerr, Richard; Jarrett, Timothy; Tannenbaum, Lawrence; Holladay, Steven D; Sharma, Ajay; Gogal, Robert M

2012-11-01

71

Congenital anomalies in low- and middle-income countries: the unborn child of global surgery.  

PubMed

Surgically correctable congenital anomalies cause a substantial burden of global morbidity and mortality. These anomalies disproportionately affect children in low- and middle-income countries (LMICs) due to sociocultural, economic, and structural factors that limit the accessibility and quality of pediatric surgery. While data from LMICs are sparse, available evidence suggests that the true human and financial cost of congenital anomalies is grossly underestimated and that pediatric surgery is a cost-effective intervention with the potential to avert significant premature mortality and lifelong disability. PMID:25135175

Sitkin, Nicole A; Ozgediz, Doruk; Donkor, Peter; Farmer, Diana L

2015-01-01

72

Reliability of CHAMP Anomaly Continuations  

NASA Technical Reports Server (NTRS)

CHAMP is recording state-of-the-art magnetic and gravity field observations at altitudes ranging over roughly 300 - 550 km. However, anomaly continuation is severely limited by the non-uniqueness of the process and satellite anomaly errors. Indeed, our numerical anomaly simulations from satellite to airborne altitudes show that effective downward continuations of the CHAMP data are restricted to within approximately 50 km of the observation altitudes while upward continuations can be effective over a somewhat larger altitude range. The great unreliability of downward continuation requires that the satellite geopotential observations must be analyzed at satellite altitudes if the anomaly details are to be exploited most fully. Given current anomaly error levels, joint inversion of satellite and near- surface anomalies is the best approach for implementing satellite geopotential observations for subsurface studies. We demonstrate the power of this approach using a crustal model constrained by joint inversions of near-surface and satellite magnetic and gravity observations for Maude Rise, Antarctica, in the southwestern Indian Ocean. Our modeling suggests that the dominant satellite altitude magnetic anomalies are produced by crustal thickness variations and remanent magnetization of the normal polarity Cretaceous Quiet Zone.

vonFrese, Ralph R. B.; Kim, Hyung Rae; Taylor, Patrick T.; Asgharzadeh, Mohammad F.

2003-01-01

73

An Extreme-Value Approach to Anomaly Vulnerability Identification  

NASA Technical Reports Server (NTRS)

The objective of this paper is to present a method for importance analysis in parametric probabilistic modeling where the result of interest is the identification of potential engineering vulnerabilities associated with postulated anomalies in system behavior. In the context of Accident Precursor Analysis (APA), under which this method has been developed, these vulnerabilities, designated as anomaly vulnerabilities, are conditions that produce high risk in the presence of anomalous system behavior. The method defines a parameter-specific Parameter Vulnerability Importance measure (PVI), which identifies anomaly risk-model parameter values that indicate the potential presence of anomaly vulnerabilities, and allows them to be prioritized for further investigation. This entails analyzing each uncertain risk-model parameter over its credible range of values to determine where it produces the maximum risk. A parameter that produces high system risk for a particular range of values suggests that the system is vulnerable to the modeled anomalous conditions, if indeed the true parameter value lies in that range. Thus, PVI analysis provides a means of identifying and prioritizing anomaly-related engineering issues that at the very least warrant improved understanding to reduce uncertainty, such that true vulnerabilities may be identified and proper corrective actions taken.

Everett, Chris; Maggio, Gaspare; Groen, Frank

2010-01-01

74

Analysis of the Candida albicans Als2p and Als4p adhesins suggests the potential for compensatory function within the Als family.  

PubMed

The ALS (agglutinin-like sequence) gene family encodes eight large cell-surface glycoproteins. The work presented here focuses on Als2p and Als4p, and is part of a larger effort to deduce the function of each Als protein. Both ALS4 alleles were deleted from the Candida albicans genome and the phenotype of the mutant strain (als4Delta/als4Delta; named 2034) studied. Loss of Als4p slowed germ tube formation of cells grown in RPMI 1640 medium and resulted in decreased adhesion of C. albicans to vascular endothelial cells. Loss of Als4p did not affect adhesion to buccal epithelial cells, biofilm formation in a catheter model, or adhesion to or destruction of oral reconstituted human epithelium (RHE). Although deletion of one ALS2 allele was achieved readily, a strain lacking the second allele was not identified despite screening thousands of transformants. The remaining ALS2 allele was placed under control of the C. albicans MAL2 promoter to create an als2Delta/PMAL2-ALS2 strain (named 2342). Real-time RT-PCR analysis of strain 2342 grown in glucose-containing medium (non-inducing conditions) showed that although ALS2 transcript levels were greatly reduced compared to wild-type cells, some ALS2 transcript remained. The decreased ALS2 expression levels were sufficient to slow germ tube formation in RPMI 1640 and Lee medium, reduce adhesion to vascular endothelial cells and to RHE, decrease RHE destruction, and impair biofilm formation. Growth of strain 2342 in maltose-containing medium (inducing conditions) restored the wild-type phenotype in all assays. Real-time RT-PCR analysis demonstrated that in maltose-containing medium, strain 2342 overexpressed ALS2 compared to wild-type cells; however no overexpression phenotype was apparent. Microarray analysis revealed little transcriptional response to ALS4 deletion, but showed twofold up-regulation of orf19.4765 in the glucose-medium-grown als2Delta/PMAL2-ALS2 strain. orf19.4765 encodes a protein with features of a glycosylated cell wall protein with similarity to Saccharomyces cerevisiae Ccw12p, although initial analysis suggested functional differences between the two proteins. Real-time RT-PCR measurement of ALS2 and ALS4 transcript copy number showed a 2.8-fold increase in ALS2 expression in the als4Delta/als4Delta strain and a 3.2-fold increase in ALS4 expression in the als2Delta/PMAL2-ALS2 strain, suggesting the potential for compensatory function between these related proteins. PMID:15870470

Zhao, X; Oh, S-H; Yeater, K M; Hoyer, L L

2005-05-01

75

Aberrant upregulation of MUC4 mucin expression in cutaneous condyloma acuminatum and squamous cell carcinoma suggests a potential role in the diagnosis and therapy of skin diseases  

PubMed Central

Aim Mucins comprise a family of high-molecular-weight glycoproteins. MUC4, a large transmembrane mucin, has recently emerged as a novel marker for diagnosis, prognosis and therapy in several malignancies. However, its role in skin pathologies remains unknown. The aim of this study was to analyse the expression of MUC4 in cutaneous pathologies by immunohistochemistry for potential diagnostic, prognostic and therapeutic applications. Methods A total of 330 tissue spots representing the normal skin, and benign and malignant cutaneous diseases, were analysed after staining with the monoclonal antibody to human MUC4 (clone 8G7). Results While the normal epidermis showed a negative to weak-positive expression of MUC4, its expression was significantly upregulated in squamous cell carcinomas (SCCs) where the intensity of staining correlated negatively with tumour grade and positively with age. A moderately strong MUC4 expression was also noted in 2/20 cancer adjacent normal skin and 2/21 chronically inflamed skin tissues, while 10/19 cases of vulval condyloma acuminate, 3/12 of vulval hyperplasia and 2 cases of verruca vulgaris also showed strong MUC4 positivity. Malignant melanoma, basal cell carcinoma and cutaneous cysts were negative. Conclusion The results indicate that MUC4 expression is aberrantly upregulated in cutaneous SCCs, vulval condylomas and verruca vulgaris. Further, it appears that MUC4 expression in the skin may be modulated by chronic inflammation and the presence of an adjacent cutaneous malignancy in certain cases. These observations suggest a novel role for MUC4 mucin in the pathogenesis of cutaneous SCC and a possible application as a diagnostic and/or prognostic marker in cutaneous pathologies. PMID:20591909

Chakraborty, Subhankar; Swanson, Benjamin J; Bonthu, Neelima; Batra, Surinder K

2010-01-01

76

The effect of scale on the interpretation of geochemical anomalies  

USGS Publications Warehouse

The purpose of geochemical surveys changes with scale. Regional surveys identify areas where mineral deposits are most likely to occur, whereas intermediate surveys identify and prioritize specific targets. At detailed scales specific deposit models may be applied and deposits delineated. The interpretation of regional geochemical surveys must take into account scale-dependent difference in the nature and objectives of this type of survey. Overinterpretation of regional data should be resisted, as should recommendations to restrict intermediate or detailed follow-up surveys to the search for specific deposit types or to a too limited suite of elements. Regional surveys identify metallogenic provinces within which a variety of deposit types and metals are most likely to be found. At intermediate scale, these regional provinces often dissipate into discrete clusters of anomalous areas. At detailed scale, individual anomalous areas reflect local conditions of mineralization and may seem unrelated to each other. Four examples from arid environments illustrate the dramatic change in patterns of anomalies between regional and more detailed surveys. On the Arabian Shield, a broad regional anomaly reflects the distribution of highly differentiated anorogenic granites. A particularly prominent part of the regional anomaly includes, in addition to the usual elements related to the granites, the assemblage of Mo, W and Sn. Initial interpretation suggested potential for granite-related, stockwork Mo deposits. Detailed work identified three separate sources for the anomaly: a metal-rich granite, a silicified and stockwork-veined area with scheelite and molybdenite, and scheelite/powellite concentrations in skarn deposits adjacent to a ring-dike complex. Regional geochemical, geophysical and remote-sensing data in the Sonoran Desert, Mexico, define a series of linear features interpreted to reflect fundamental, northeast-trending fractures in the crust that served as the prime conduits for mineralizing fluids. At a larger scale, the linear, northeast-trending anomalies can be shown to result from a series of discrete mineralized systems with different ages and mineral assemblages. The linear pattern of anomalies disintegrates. A regional geochemical survey in the Sonoran Desert in southwestern Arizona displays a cluster of samples anomalous in Pb, Mo, Bi and W. In detail, the original regional anomaly separates into four discrete anomalous areas, each with its own distinctive suite of elements, geographic distribution and age of mineralization. A prominent regional gold anomaly in the Gobi Desert, Xinjiang, Peoples Republic of China, extends southeastward for 30 km from known lode gold deposits. Because the anomaly cuts both lithologic units and the structural grain, and because it parallels the prevailing direction of high-velocity winds, it was originally attributed to eolian dispersion. In detail, the regional anomaly consists of several east-west-trending anomalies, parallel to local lithology and structure that most likely reflect independent sources of lode gold. The regional anomaly results from smoothing of an en-echelon set of local anomalies. These examples emphasize that interpretation of regional anomalies must be tempered to consider regional-sized geologic features. Attempts to overinterpret anomalies by assigning deposit-scale attributes to regional anomalies can lead to confusion and incorrect interpretations. Potential targets that can be readily resolved only at intermediate or detailed scales of study may be overlooked. ?? 1991.

Theobald, P.K.; Eppinger, R.G.; Turner, R.L.; Shiquan, S.

1991-01-01

77

Classifying sex biased congenital anomalies  

SciTech Connect

The reasons for sex biases in congenital anomalies that arise before structural or hormonal dimorphisms are established has long been unclear. A review of such disorders shows that patterning and tissue anomalies are female biased, and structural findings are more common in males. This suggests different gender dependent susceptibilities to developmental disturbances, with female vulnerabilities focused on early blastogenesis/determination, while males are more likely to involve later organogenesis/morphogenesis. A dual origin for some anomalies explains paradoxical reductions of sex biases with greater severity (i.e., multiple rather than single malformations), presumably as more severe events increase the involvement of an otherwise minor process with opposite biases to those of the primary mechanism. The cause for these sex differences is unknown, but early dimorphisms, such as differences in growth or presence of H-Y antigen, may be responsible. This model provides a useful rationale for understanding and classifying sex-biased congenital anomalies. 42 refs., 7 tabs.

Lubinsky, M.S. [Medical College of Wisconsin and Children`s Hospital, Milwaukee, WI (United States)] [Medical College of Wisconsin and Children`s Hospital, Milwaukee, WI (United States)

1997-03-31

78

Experimental Investigation into the Radar Anomalies on the Surface of Venus  

NASA Technical Reports Server (NTRS)

Radar mapping of thc surface of Venus shows areas of high reflectivity (low emissivity) in the Venusian highlands at altitudes between 2.5-4.75 kilometers. The origin of the radar anomalies found in the Venusian highlands remains unclear. Most explanations of the potential causes for these radar anomalies come from theoretical work. Previous studies suggest increased surface roughness or materials with higher dielectric constants as well as surface atmospheric interactions. Several possible candidates of high-dielectric materials are tellurium) ferroelectric materials, and lead or bismuth sulfides. While previous studies have been influential in determining possible sources for the Venus anomalies, only a very few hypotheses have been verified via experimentation. This work intends to experimentally constrain the source of the radar anomalies on Venus. This study proposes to investigate four possible materials that could potentially cause the high reflectivities on the surface of Venus and tests their behavior under simulated Venusian conditions.

Kohler, E.; Gavin, P.; Chevrier, V.; Johnson, Natasha M.

2012-01-01

79

Congenital coronary anomalies detected by coronary computed tomography compared to invasive coronary angiography  

PubMed Central

Background As coronary computed tomography angiography (CCTA) has emerged as a non-invasive alternative for evaluation of coronary anatomy with a lower referral threshold than invasive coronary angiography (ICA), the prevalence of coronary anomalies in CCTA may more closely reflect the true prevalence in the general population. Morphological features of coronary anomalies can be evaluated more precisely by CCTA than by ICA, which might lead to a higher identification of congenital coronary anomalies in CCTA compared to ICA. To evaluate the incidence, clinical and morphological features of the anatomy of patients with coronary anomalies detected either by coronary computed tomography angiography (CCTA) with prospective ECG-triggering or invasive coronary angiography (ICA). Methods Consecutive patients underwent 64-slice CCTA (n?=?1?759) with prospective ECG-triggering or ICA (n?=?9?782) and coronary anatomy was evaluated for identification of coronary anomalies to predefined criteria (origin, course and termination) according to international recommendations. Results The prevalence of coronary anomalies was 7.9% (n?=?138) in CCTA and 2.1% in ICA (n?=?203; p?anomaly detected by CCTA was myocardial bridging 42.8% (n?=?59) vs. 21.2% (n?=?43); p?anomaly 36.0% (n?=?73; p?anomalies in CCTA 9.4% were potentially serious coronary anaomalies, defined as a course of the coronary artery between aorta and pulmonary artery were identified. Conclusion The prevalence of coronary anomalies is substantially higher with CCTA than ICA even after exclusion of patients with myocardial bridging which is more frequently found with CCTA. This suggests that the true prevalence of coronary anomalies in the general population may have been underestimated based on ICA. PMID:25004927

2014-01-01

80

Large interannual Arctic sea-ice anomalies in the coming decades: is there hope to predict them?  

NASA Astrophysics Data System (ADS)

In projections of 21st-century climate, Arctic sea ice declines and at the same time exhibits strong interannual anomalies. Here, we investigate the potential to predict these strong sea-ice anomalies under a perfect-model assumption, using the Max-Planck-Institute Earth System Model in the same setup as in the Coupled Model Intercomparison Project Phase 5 (CMIP5). We study two cases of strong negative sea-ice anomalies: a five-year-long anomaly for present-day conditions, and a ten-year-long anomaly for conditions projected for the middle of the 21st century. We treat these anomalies in the CMIP5 projections as the truth, and use exactly the same model configuration for predictions of this synthetic truth. We start ensemble predictions at different times during the anomalies, considering lagged-perfect and sea-ice-assimilated initial conditions. We find that the onset and amplitude of the interannual anomalies are not predictable. However, the further deepening of the anomaly can be predicted for typically one year lead time if predictions start after the onset but before the maximal amplitude of the anomaly. The magnitude of an extremely low summer sea-ice minimum is hard to predict: the skill of the prediction ensemble is not better than a damped-persistence forecast for lead times of more than a few months, and is not better than a climatology forecast for lead times of two or more years. Predictions of the present-day anomaly are more skillful than predictions of the mid-century anomaly. Predictions using sea-ice-assimilated initial conditions are competitive with those using lagged-perfect initial conditions for lead times of a year or less, but yield degraded skill for longer lead times. The results presented here suggest that there is limited prospect of predicting the large interannual sea-ice anomalies expected to occur throughout the 21st century.

Tietsche, Steffen; Notz, Dirk; Jungclaus, Johann H.; Marotzke, Jochem

2013-04-01

81

Chiral anomalies and differential geometry  

SciTech Connect

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. (WHK)

Zumino, B.

1983-10-01

82

Small cosmological constant from the QCD trace anomaly?  

PubMed

According to recent astrophysical observations the large scale mean pressure of our present Universe is negative suggesting a positive cosmological constant-like term. The issue of whether nonperturbative effects of self-interacting quantum fields in curved space-times may yield a significant contribution is addressed. Focusing on the trace anomaly of quantum chromodynamics, a preliminary estimate of the expected order of magnitude yields a remarkable coincidence with the empirical data, indicating the potential relevance of this effect. PMID:12190454

Schützhold, Ralf

2002-08-19

83

Uhl's anomaly: a difficult prenatal diagnosis.  

PubMed

Uhl's anomaly is an evolutive disease leading to terminal right ventricular failure. The most difficult differential diagnosis at presentation is the Ebstein disease. We describe the evolution of a foetus with Uhl's anomaly from 21 to 30 weeks of gestation, with progressive reduction in the right ventricular anterior myocardium suggestive of apoptosis, leading to foetal demise. PMID:24784726

Vaujois, Laurence; van Doesburg, Nicolaas; Raboisson, Marie-Josée

2015-03-01

84

Anomaly Detection for Cybersecurity of the Substations  

Microsoft Academic Search

Cybersecurity of the substations in a power system is a major issue as the substations become increasingly dependent on computer and communication networks. This paper is concerned with anomaly detection in the computer network environment of a substation. An anomaly inference algorithm is proposed for early detection of cyber-intrusions at the substations. The potential sce- nario of simultaneous intrusions launched

Chee-Wooi Ten; Junho Hong; Chen-Ching Liu

2011-01-01

85

An Analysis of the 1999 DARPA\\/Lincoln Laboratory Evaluation Data for Network Anomaly Detection  

Microsoft Academic Search

We investigate potential simulation artifacts and their effects on the evaluation of network anomaly detection systems in the 1999 DARPA\\/MIT Lincoln Laboratory off-line intrusion detection evaluation data set. A statistical comparison of the simulated b ackground and training traffic with real t raffic c ollected from a university departmental server suggests the presence of artifacts that could allow a network

Matthew V. Mahoney; Philip K. Chan

2003-01-01

86

Multiple myeloma-associated hDIS3 mutations cause perturbations in cellular RNA metabolism and suggest hDIS3 PIN domain as a potential drug target.  

PubMed

hDIS3 is a mainly nuclear, catalytic subunit of the human exosome complex, containing exonucleolytic (RNB) and endonucleolytic (PIN) active domains. Mutations in hDIS3 have been found in ?10% of patients with multiple myeloma (MM). Here, we show that these mutations interfere with hDIS3 exonucleolytic activity. Yeast harboring corresponding mutations in DIS3 show growth inhibition and changes in nuclear RNA metabolism typical for exosome dysfunction. Construction of a conditional DIS3 knockout in the chicken DT40 cell line revealed that DIS3 is essential for cell survival, indicating that its function cannot be replaced by other exosome-associated nucleases: hDIS3L and hRRP6. Moreover, HEK293-derived cells, in which depletion of endogenous wild-type hDIS3 was complemented with exogenously expressed MM hDIS3 mutants, proliferate at a slower rate and exhibit aberrant RNA metabolism. Importantly, MM mutations are synthetically lethal with the hDIS3 PIN domain catalytic mutation both in yeast and human cells. Since mutations in PIN domain alone have little effect on cell physiology, our results predict the hDIS3 PIN domain as a potential drug target for MM patients with hDIS3 mutations. It is an interesting example of intramolecular synthetic lethality with putative therapeutic potential in humans. PMID:24150935

Tomecki, Rafal; Drazkowska, Karolina; Kucinski, Iwo; Stodus, Krystian; Szczesny, Roman J; Gruchota, Jakub; Owczarek, Ewelina P; Kalisiak, Katarzyna; Dziembowski, Andrzej

2014-01-01

87

Multiple myeloma-associated hDIS3 mutations cause perturbations in cellular RNA metabolism and suggest hDIS3 PIN domain as a potential drug target  

PubMed Central

hDIS3 is a mainly nuclear, catalytic subunit of the human exosome complex, containing exonucleolytic (RNB) and endonucleolytic (PIN) active domains. Mutations in hDIS3 have been found in ?10% of patients with multiple myeloma (MM). Here, we show that these mutations interfere with hDIS3 exonucleolytic activity. Yeast harboring corresponding mutations in DIS3 show growth inhibition and changes in nuclear RNA metabolism typical for exosome dysfunction. Construction of a conditional DIS3 knockout in the chicken DT40 cell line revealed that DIS3 is essential for cell survival, indicating that its function cannot be replaced by other exosome-associated nucleases: hDIS3L and hRRP6. Moreover, HEK293-derived cells, in which depletion of endogenous wild-type hDIS3 was complemented with exogenously expressed MM hDIS3 mutants, proliferate at a slower rate and exhibit aberrant RNA metabolism. Importantly, MM mutations are synthetically lethal with the hDIS3 PIN domain catalytic mutation both in yeast and human cells. Since mutations in PIN domain alone have little effect on cell physiology, our results predict the hDIS3 PIN domain as a potential drug target for MM patients with hDIS3 mutations. It is an interesting example of intramolecular synthetic lethality with putative therapeutic potential in humans. PMID:24150935

Tomecki, Rafal; Drazkowska, Karolina; Kucinski, Iwo; Stodus, Krystian; Szczesny, Roman J.; Gruchota, Jakub; Owczarek, Ewelina P.; Kalisiak, Katarzyna; Dziembowski, Andrzej

2014-01-01

88

Exploratory and spatial data analysis (EDA-SDA) for determining regional background levels and anomalies of potentially toxic elements in soils from Catorce-Matehuala, Mexico  

USGS Publications Warehouse

The threshold between geochemical background and anomalies can be influenced by the methodology selected for its estimation. Environmental evaluations, particularly those conducted in mineralized areas, must consider this when trying to determinate the natural geochemical status of a study area, quantifying human impacts, or establishing soil restoration values for contaminated sites. Some methods in environmental geochemistry incorporate the premise that anomalies (natural or anthropogenic) and background data are characterized by their own probabilistic distributions. One of these methods uses exploratory data analysis (EDA) on regional geochemical data sets coupled with a geographic information system (GIS) to spatially understand the processes that influence the geochemical landscape in a technique that can be called a spatial data analysis (SDA). This EDA-SDA methodology was used to establish the regional background range from the area of Catorce-Matehuala in north-central Mexico. Probability plots of the data, particularly for those areas affected by human activities, show that the regional geochemical background population is composed of smaller subpopulations associated with factors such as soil type and parent material. This paper demonstrates that the EDA-SDA method offers more certainty in defining thresholds between geochemical background and anomaly than a numeric technique, making it a useful tool for regional geochemical landscape analysis and environmental geochemistry studies.

Chiprés, J.A.; Castro-Larragoitia, J.; Monroy, M.G.

2009-01-01

89

New insights into global patterns of ocean temperature anomalies  

E-print Network

the spatial and temporal characteristics of temperature anomalies related to both coral bleaching and disease spatial patterns in coral bleaching- and disease-related anomalies as well as for designing protected results suggest that temperature anomalies related to coral bleaching and disease are likely to be highly

Bruno, John F.

90

Suppressed neuroendocrine stress response in depressed women on job-stress related long-term sick-leave: A stable marker potentially suggestive of pre-existing vulnerability  

PubMed Central

Background We recently reported marked hyporeactivity of the hypothalamo-pituitary-adrenal (HPA) axis in depressed females on job-stress related long-term sick-leave (LTSL). This unexpected finding prompted the question whether HPA-axis hypofunction in this group results from stress exposure, or reflects pre-existing vulnerability. Here, as a first step toward addressing this question, we assessed temporal stability of HPA-axis reactivity in these subjects. Methods We used the combined dexamethasone/corticotropin-releasing hormone (DEX-CRH) test to retest HPA-axis reactivity in 29 patients and 27 controls after 12 months follow-up. Clinical status and cognitive performance was also retested. Results Despite marked clinical improvement, and normalization of initially observed impairments in attention and working memory, marked HPA-axis hyporeactivity persisted in patients. A high test – retest correlation was found both at the level of ACTH (R=0.85, p<0.001) and cortisol (R=0.76, p<0.001) responses. Conclusions Hyporeactivity of the HPA was stable over 12 months in LTSL subjects, independently of clinical improvement and normalized cognitive function. The stability of this response over time suggests that decreased DEX-CRH responses in this group may be a trait rather than a state marker. This finding is compatible with a hypothesis that HPA-axis hyporeactivity may reflect a pre-existing vulnerability in these subjects. PMID:19058782

Wahlberg, Kristina; Ghatan, Per Hamid; Modell, Sieglinde; Nygren, Åke; Ingvar, Martin; Åsberg, Marie; Heilig, Markus

2009-01-01

91

Effects of hand orientation on motor imagery--event related potentials suggest kinesthetic motor imagery to solve the hand laterality judgment task.  

PubMed

Motor imagery (MI) refers to the process of imagining the execution of a specific motor action without actually producing an overt movement. Two forms of MI have been distinguished: visual MI and kinesthetic MI. To distinguish between these forms of MI we employed an event related potential (ERP) study to measure interference effects induced by hand orientation manipulations in a hand laterality judgement task. We hypothesized that this manipulation should only affect kinesthetic MI but not visual MI. The ERPs elicited by rotated hand stimuli contained the classic rotation related negativity (RRN) with respect to palm view stimuli. We observed that laterally rotated stimuli led to a more marked RRN than medially rotated stimuli. This RRN effect was observed when participants had their hands positioned in either a straight (control) or an inward rotated posture, but not when their hands were positioned in an outward rotated posture. Posture effects on the ERP-RRN have not previously been studied. Apparently, a congruent hand posture (hands positioned in an outward rotated fashion) facilitates the judgement of the otherwise more demanding laterally rotated hand stimuli. These ERP findings support a kinesthetic interpretation of MI involved in solving the hand laterality judgement task. The RRN may be used as a non-invasive marker for kinesthetic MI and seems useful in revealing the covert behavior of MI in e.g. rehabilitation programs. PMID:24086747

Jongsma, Marijtje L A; Meulenbroek, Ruud G J; Okely, Judith; Baas, C Marjolein; van der Lubbe, Rob H J; Steenbergen, Bert

2013-01-01

92

SRY interference of normal regulation of the RET gene suggests a potential role of the Y-chromosome gene in sexual dimorphism in Hirschsprung disease.  

PubMed

The Hirschsprung disease (HSCR) is a complex congenital disorder, arising from abnormalities in enteric nervous system (ENS) development. There is a gender disparity among the patients, with the male to female ratio as high as 5 : 1. Loss-of-function mutations of HSCR genes and haploinsufficiency of their gene products are the primary pathogenic mechanisms for disease development. Recent studies identified over half of the HSCR disease susceptibility genes as targets for the sex-determining factor SRY, suggesting that this Y-encoded transcription factor could be involved in sexual dimorphism in HSCR. Among the SRY targets, the tyrosine kinase receptor RET represents the most important disease gene, whose mutations account for half of the familial and up to one-third of the sporadic forms of HSCR. RET is regulated by a distal and a proximal enhancer at its promoter, in which PAX3 and NKX2-1 are the resident transcription factors respectively. We show that the SRY-box 10 (SOX10) co-activator interacts and forms transcriptional complexes with PAX3 and NKX2-1 in a sequence-independent manner and exacerbates their respective transactivation activities on the RET promoter. SRY competitively displaces SOX10 in such transcription complexes and represses their regulatory functions on RET. Hence SRY could be a Y-located negative modifier of RET expression; and if it is ectopically expressed during ENS development, such SRY repression could result in RET protein haploinsufficiency and promotion of HSCR development, thereby contributing to sexual dimorphism in HSCR. PMID:25267720

Li, Yunmin; Kido, Tatsuo; Garcia-Barcelo, Maria M; Tam, Paul K H; Tabatabai, Z Laura; Lau, Yun-Fai Chris

2015-02-01

93

Analysis of spacecraft anomalies  

NASA Technical Reports Server (NTRS)

The anomalies from 316 spacecraft covering the entire U.S. space program were analyzed to determine if there were any experimental or technological programs which could be implemented to remove the anomalies from future space activity. Thirty specific categories of anomalies were found to cover nearly 85 percent of all observed anomalies. Thirteen experiments were defined to deal with 17 of these categories; nine additional experiments were identified to deal with other classes of observed and anticipated anomalies. Preliminary analyses indicate that all 22 experimental programs are both technically feasible and economically viable.

Bloomquist, C. E.; Graham, W. C.

1976-01-01

94

WF4 Anomaly Characterization  

NASA Astrophysics Data System (ADS)

A serious anomaly has been found in images from the WF4 CCD in WFPC2. The WF4 CCD bias level appears to have become unstable, resulting in sporadic images with either low or zero bias level. The severity and frequency of the problem is rapidly increasing, and it is possible that WF4 will soon become unusable if no work-around is found. The other three CCDs {PC1, WF2, and WF3} appear to be unaffected and continue to operate properly. The impacts from "low" and "zero" bias are somewhat different, but in both cases the effects are immediately obvious. Images with low bias will tend to have horizontal {x-direction} streaks and stripes with an amplitude of ? about 0.5 DN in WF4. We believe these data should be mostly recoverable with some effort, though at a loss in the detectability of faint targets. "Zero bias" is a much more serious problem and is evidenced by images which are blank in WF4, except for showing occasional cosmic rays, bright targets, and negative pixels from dark subtraction. These images with zero bias are probably unusable for most purposes. Both the CCD gain settings of 7 and 14 are affected. The frequency of the anomaly is rapidly increasing. The first significant instances of low bias appear to have been in late 2004 when a few images were impacted. However, within the last few weeks over half the images are beginning to show the low bias problem. The more serious "zero bias" problem appears to have first occurred in Feb. 2005, but it is also increasing and now impacts 10% to 20% of WFPC2 images. At present there are still many images which appear fine and unaffected, but the situation is quickly evolving. We believe the science impact for most observers will be minimal. Targets are by default placed on either PC1 or WF3 which continue to operate properly. However, observers requiring the full field of view {survey projects, large targets, etc.} will potentially lose one-third of their imaging area. Our understanding of this anomaly is still evolving, and most of the information is tentative. Additional details will be posted on the WFPC2 website as they become available.

Biretta, John

2005-07-01

95

Chromium isotopic anomalies in the Allende meteorite  

NASA Technical Reports Server (NTRS)

Abundances of the chromium isotopes in terrestrial and bulk meteorite samples are identical to 0.01 percent. However, Ca-Al-rich inclusions from the Allende meteorite show endemic isotopic anomalies in chromium which require at least three nucleosynthetic components. Large anomalies at Cr-54 in a special class of inclusions are correlated with large anomalies at Ca-48 and Ti-50 and provide strong support for a component reflecting neutron-rich nucleosynthesis at nuclear statistical equilibrium. This correlation suggests that materials from very near the core of an exploding massive star may be injected into the interstellar medium.

Papanastassiou, D. A.

1986-01-01

96

Magnetosheath Flow Anomalies in 3-D  

NASA Technical Reports Server (NTRS)

Measurements of the plasma and magnetic field with high temporal resolution on the Interball Tail probe reveal many flow anomalies in the magnetosheath. They are usually seen as flow direction and number density variations, accompanied by magnetic field discontinuities. Large flow anomalies with number density variations of factor of 2 or more and velocity variations of 100 km/s or more are seen with periodicity of about I per hour. The cases of flow anomalies following in succession are also observed, and suggest their decay while propagating through the magnetosheath. Some magnetospheric disturbances observed in the outer magnetosphere after the satellite has crossed the magnetopause on the inbound orbit suggest their association with magnetosheath flow anomalies observed in the magnetosheath prior to magnetopause crossing.

Vaisberg, O. L.; Burch, J. L.; Smirnov, V. N.; Avanov, L. A.; Moore, T. E.; Waite, J. H., Jr.; Skalsky, A. A.; Borodkova, N. L.; Coffey, V. N.; Gallagher, D. L.; Rose, M. Franklin (Technical Monitor)

2000-01-01

97

Response of African humid tropical forests to recent rainfall anomalies  

PubMed Central

During the last decade, strong negative rainfall anomalies resulting from increased sea surface temperature in the tropical Atlantic have caused extensive droughts in rainforests of western Amazonia, exerting persistent effects on the forest canopy. In contrast, there have been no significant impacts on rainforests of West and Central Africa during the same period, despite large-scale droughts and rainfall anomalies during the same period. Using a combination of rainfall observations from meteorological stations from the Climate Research Unit (CRU; 1950–2009) and satellite observations of the Tropical Rainfall Measuring Mission (TRMM; 1998–2010), we show that West and Central Africa experienced strong negative water deficit (WD) anomalies over the last decade, particularly in 2005, 2006 and 2007. These anomalies were a continuation of an increasing drying trend in the region that started in the 1970s. We monitored the response of forests to extreme rainfall anomalies of the past decade by analysing the microwave scatterometer data from QuickSCAT (1999–2009) sensitive to variations in canopy water content and structure. Unlike in Amazonia, we found no significant impacts of extreme WD events on forests of Central Africa, suggesting potential adaptability of these forests to short-term severe droughts. Only forests near the savanna boundary in West Africa and in fragmented landscapes of the northern Congo Basin responded to extreme droughts with widespread canopy disturbance that lasted only during the period of WD. Time-series analyses of CRU and TRMM data show most regions in Central and West Africa experience seasonal or decadal extreme WDs (less than ?600 mm). We hypothesize that the long-term historical extreme WDs with gradual drying trends in the 1970s have increased the adaptability of humid tropical forests in Africa to droughts. PMID:23878335

Asefi-Najafabady, Salvi; Saatchi, Sassan

2013-01-01

98

The Life of Suggestions  

ERIC Educational Resources Information Center

Using the notion of a suggestion, or rather charting the life of suggestions, this article considers the happenings of chance and embodiment as the "problems that got away." The life of suggestions helps us to ask how connectivities are made, how desire functions, and how "immanence" rather than "transcendence" can open up the politics and ethics…

Pearce, Cathie

2010-01-01

99

A Search for Anomalies  

Microsoft Academic Search

Since 1965 I have been culling systematically from the literature of science those observations that challenge reigning paradigms. The tangible result of the thousands of hours spent in libraries has been a series of Sourcebooks, Handbooks, and Catalogs that, at present, describe and evaluate roughly 2,000 anomalies— about one-half of my total collection. Some of these anomalies are truly profound

WILLIAM R. CORLISS

100

Generalized curvature and Ricci tensors for a higher spin potential and the trace anomaly in external higher spin fields in AdS 4 space  

Microsoft Academic Search

The curvature of a higher spin potential as constructed in a previous article of the same authors [R. Manvelyan, W. Rühl, The generalized curvature and Christoffel symbols for a higher spin potential in AdSd+1 space, arXiv: 0705.3528 [hep-th

Ruben Manvelyan; Werner Rühl

2008-01-01

101

Isotopic anomalies in extraterrestrial grains.  

PubMed

Isotopic compositions are referred to as anomalous if the isotopic ratios measured cannot be related to the terrestrial (solar) composition of a given element. While small effects close to the resolution of mass spectrometric techniques can have ambiguous origins, the discovery of large isotopic anomalies in inclusions and grains from primitive meteorites suggests that material from distinct sites of stellar nucleosynthesis has been preserved. Refractory inclusions, which are predominantly composed of the refractory oxides of Al, Ca, Ti, and Mg, in chondritic meteorites commonly have excesses in the heaviest isotopes of Ca, Ti, and Cr which are inferred to have been produced in a supernova. Refractory inclusions also contain excess 26Mg from short lived 26Al decay. However, despite the isotopic anomalies indicating the preservation of distinct nucleosynthetic sites, refractory inclusions have been processed in the solar system and are not interstellar grains. Carbon (graphite and diamond) and silicon carbide grains from the same meteorites also have large isotopic anomalies but these phases are not stable in the oxidized solar nebula which suggests that they are presolar and formed in the circumstellar atmospheres of carbon-rich stars. Diamond has a characteristic signature enriched in the lightest and heaviest isotopes of Xe, and graphite shows a wide range in C isotopic compositions. SiC commonly has C and N isotopic signatures which are characteristic of H-burning in the C-N-O cycle in low-mass stars. Heavier elements such as Si, Ti, Xe, Ba, and Nd, carry an isotopic signature of the s-process. A minor population of SiC (known as Grains X, ca. 1%) are distinct in having decay products of short lived isotopes 26Al (now 26Mg), 44Ti (now 44Ca), and 49V (now 49Ti), as well as 28Si excesses which are characteristic of supernova nucleosynthesis. The preservation of these isotopic anomalies allows the examination of detailed nucleosynthetic pathways in stars. PMID:11541324

Ireland, T R

1996-03-01

102

Gravitational Anomaly and Transport  

E-print Network

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.

Karl Landsteiner; Eugenio Megias; Francisco Pena-Benitez

2011-03-25

103

Gravitational Anomaly and Transport  

E-print Network

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.

Landsteiner, Karl; Pena-Benitez, Francisco

2011-01-01

104

Vascular anomalies in children.  

PubMed

The process of understanding and treating children with vascular anomalies has been hampered by confusing and occasionally incorrect terminology. The most important step when evaluating a maxillofacial vascular anomaly is to determine whether it is a tumor or a malformation. In most cases, this diagnosis can be made by history and physical examination. Selective radiographic imaging is helpful in differentiating vascular malformations or the extent of bony involvement and/or destruction. Children with vascular anomalies should be managed by an interdisciplinary team of trained providers who are committed to following, treating, and studying patients with these complex problems. PMID:22771277

Abramowicz, Shelly; Padwa, Bonnie L

2012-08-01

105

Open To Suggestion.  

ERIC Educational Resources Information Center

Suggests class activities in three short articles including: (1) "Students Evaluate Reading," by Lenore Sandel; (2) "Solving Verbal Analogies," by Edward J. Dwyer; and (3) "Becoming Testwise," by Dean Schoen. (RS)

Journal of Reading, 1988

1988-01-01

106

Astrometric Solar-System Anomalies  

NASA Astrophysics Data System (ADS)

There are four unexplained anomalies connected with astrometric data. Perhaps the most disturbing is the fact that when a spacecraft on a flyby trajectory approaches the Earth within 2000 km or less, it experiences a gain in total orbital energy per unit mass (Anderson et al., Phys. Rev. Lett. 100, 091102). This amounts to a net velocity increase of 13.5 mm/s for the NEAR spacecraft at a closest approach of 539 km, 3.9 mm/s for the Galileo spacecraft at 960 km, and 1.8 mm/s for the Rosetta spacecraft at 1956 km. Next, I suggest the change in the astronomical unit AU is definitely a concern. It is increasing by about 15 cm/yr (Krasinsky and Brumberg, Celes. Mech. & Dynam. Astron. 90, 267). The other two anomalies are perhaps less disturbing because of known sources of nongravitational acceleration. The first is an apparent slowing of the two Pioneer spacecraft as they exit the solar system in opposite directions (Anderson et al., Phys. Rev. D 65, 082004). Some, including me, are convinced this effect is of concern, but many are convinced it is produced by a nearly identical thermal emission from both spacecraft, in a direction away from the Sun, thereby producing acceleration toward the Sun. The fourth anomaly is a measured increase in the eccentricity of the Moon's orbit. Here again, an increase is expected from tidal friction in both the Earth and Moon. However, there is a reported increase that is about three times larger than expected (J. G. Williams, DDA/AAS Brouwer Award Lecture, Halifax, Nova Scotia 2006). We suspect that all four anomalies have mundane explanations. However, the possibility that they will be explained by a new theory of gravitation is not ruled out, perhaps analogous to Einstein's 1916 explanation of the excess precession of Mercury's perihelion.

Anderson, John D.

2009-05-01

107

Advancements of Data Anomaly Detection Research in Wireless Sensor Networks: A Survey and Open Issues  

PubMed Central

Wireless Sensor Networks (WSNs) are important and necessary platforms for the future as the concept “Internet of Things” has emerged lately. They are used for monitoring, tracking, or controlling of many applications in industry, health care, habitat, and military. However, the quality of data collected by sensor nodes is affected by anomalies that occur due to various reasons, such as node failures, reading errors, unusual events, and malicious attacks. Therefore, anomaly detection is a necessary process to ensure the quality of sensor data before it is utilized for making decisions. In this review, we present the challenges of anomaly detection in WSNs and state the requirements to design efficient and effective anomaly detection models. We then review the latest advancements of data anomaly detection research in WSNs and classify current detection approaches in five main classes based on the detection methods used to design these approaches. Varieties of the state-of-the-art models for each class are covered and their limitations are highlighted to provide ideas for potential future works. Furthermore, the reviewed approaches are compared and evaluated based on how well they meet the stated requirements. Finally, the general limitations of current approaches are mentioned and further research opportunities are suggested and discussed. PMID:23966182

Rassam, Murad A.; Zainal, Anazida; Maarof, Mohd Aizaini

2013-01-01

108

Advancements of data anomaly detection research in wireless sensor networks: a survey and open issues.  

PubMed

Wireless Sensor Networks (WSNs) are important and necessary platforms for the future as the concept "Internet of Things" has emerged lately. They are used for monitoring, tracking, or controlling of many applications in industry, health care, habitat, and military. However, the quality of data collected by sensor nodes is affected by anomalies that occur due to various reasons, such as node failures, reading errors, unusual events, and malicious attacks. Therefore, anomaly detection is a necessary process to ensure the quality of sensor data before it is utilized for making decisions. In this review, we present the challenges of anomaly detection in WSNs and state the requirements to design efficient and effective anomaly detection models. We then review the latest advancements of data anomaly detection research in WSNs and classify current detection approaches in five main classes based on the detection methods used to design these approaches. Varieties of the state-of-the-art models for each class are covered and their limitations are highlighted to provide ideas for potential future works. Furthermore, the reviewed approaches are compared and evaluated based on how well they meet the stated requirements. Finally, the general limitations of current approaches are mentioned and further research opportunities are suggested and discussed. PMID:23966182

Rassam, Murad A; Zainal, Anazida; Maarof, Mohd Aizaini

2013-01-01

109

Soybean Insect Control Suggestions.  

E-print Network

Protecting Bees and Other Pollinators from Insecticides .............................. 10 Policy Statement for Making Chemical Control Recommendations ....................... 11 Soybean Insect Control Suggestions (chart) ... 12 Conversion Table... and maximum coverage. When making any insecticide applications, follow label directions. Refer to the ((Protecting Bees and other Pollinators from Insecticides" section of this bulletin to avoid bee losses. Biological Insecticides ':,.,.dcillus...

Drees, B.M.

1985-01-01

110

Paleo-Pole Positions from Martian Magnetic Anomaly Data  

NASA Technical Reports Server (NTRS)

Magnetic component anomaly maps were made from five mapping cycles of the Mars Global Surveyor s magnetometer data. Our goal was to find and isolate positive and negative anomaly pairs which would indicate magnetization of a single source body. From these anomalies we could compute the direction of the magnetizing vector and subsequently the location of the magnetic pole existing at the time of magnetization. We found nine suitable anomaly pairs and from these we computed four North and 3 South poles with two at approximately 60 degrees north latitude. These results suggest that during the existence of the Martian main magnetic field it experienced several reversals.

Taylor, Patrick T.; Frawley, James J.

2003-01-01

111

Astrometric solar system anomalies  

SciTech Connect

There are at least four unexplained anomalies connected with astrometric data. perhaps the most disturbing is the fact that when a spacecraft on a flyby trajectory approaches the Earth within 2000 km or less, it often experiences a change in total orbital energy per unit mass. next, a secular change in the astronomical unit AU is definitely a concern. It is increasing by about 15 cm yr{sup -1}. The other two anomalies are perhaps less disturbing because of known sources of nongravitational acceleration. The first is an apparent slowing of the two Pioneer spacecraft as they exit the solar system in opposite directions. Some astronomers and physicists are convinced this effect is of concern, but many others are convinced it is produced by a nearly identical thermal emission from both spacecraft, in a direction away from the Sun, thereby producing acceleration toward the Sun. The fourth anomaly is a measured increase in the eccentricity of the Moon's orbit. Here again, an increase is expected from tidal friction in both the Earth and Moon. However, there is a reported unexplained increase that is significant at the three-sigma level. It is produent to suspect that all four anomalies have mundane explanations, or that one or more anomalies are a result of systematic error. Yet they might eventually be explained by new physics. For example, a slightly modified theory of gravitation is not ruled out, perhaps analogous to Einstein's 1916 explanation for the excess precession of Mercury's perihelion.

Nieto, Michael Martin [Los Alamos National Laboratory; Anderson, John D [PROPULSION LABORATORY

2009-01-01

112

Dealing with Ebstein's anomaly.  

PubMed

Ebstein's anomaly is a complex congenital disorder of the tricuspid valve. Presentation in neonatal life and (early) childhood is common. Disease severity and clinical features vary widely and require a patient-tailored treatment. In this review, we describe the natural history of children and adolescents with Ebstein's anomaly, including symptoms and signs presenting at diagnosis. Current classification strategies of Ebstein's anomaly are discussed. We report on diagnostic methods for establishing the severity of disease that might enhance decision on the timing of surgical intervention. Furthermore, we describe different surgical options for severely ill neonates and multiple surgical interventions after infancy. Only with ample knowledge and understanding of the above, this complex and diverse group of patients can be correctly treated in order to improve not only duration, but also quality of life. PMID:24169373

Geerdink, Lianne M; Kapusta, Livia

2014-04-01

113

Modeling And Detecting Anomalies In Scada Systems  

NASA Astrophysics Data System (ADS)

The detection of attacks and intrusions based on anomalies is hampered by the limits of specificity underlying the detection techniques. However, in the case of many critical infrastructure systems, domain-specific knowledge and models can impose constraints that potentially reduce error rates. At the same time, attackers can use their knowledge of system behavior to mask their manipulations, causing adverse effects to observed only after a significant period of time. This paper describes elementary statistical techniques that can be applied to detect anomalies in critical infrastructure networks. A SCADA system employed in liquefied natural gas (LNG) production is used as a case study.

Svendsen, Nils; Wolthusen, Stephen

114

Whole exome sequence analysis of Peters anomaly.  

PubMed

Peters anomaly is a rare form of anterior segment ocular dysgenesis, which can also be associated with additional systemic defects. At this time, the majority of cases of Peters anomaly lack a genetic diagnosis. We performed whole exome sequencing of 27 patients with syndromic or isolated Peters anomaly to search for pathogenic mutations in currently known ocular genes. Among the eight previously recognized Peters anomaly genes, we identified a de novo missense mutation in PAX6, c.155G>A, p.(Cys52Tyr), in one patient. Analysis of 691 additional genes currently associated with a different ocular phenotype identified a heterozygous splicing mutation c.1025+2T>A in TFAP2A, a de novo heterozygous nonsense mutation c.715C>T, p.(Gln239*) in HCCS, a hemizygous mutation c.385G>A, p.(Glu129Lys) in NDP, a hemizygous mutation c.3446C>T, p.(Pro1149Leu) in FLNA, and compound heterozygous mutations c.1422T>A, p.(Tyr474*) and c.2544G>A, p.(Met848Ile) in SLC4A11; all mutations, except for the FLNA and SLC4A11 c.2544G>A alleles, are novel. This is the first study to use whole exome sequencing to discern the genetic etiology of a large cohort of patients with syndromic or isolated Peters anomaly. We report five new genes associated with this condition and suggest screening of TFAP2A and FLNA in patients with Peters anomaly and relevant syndromic features and HCCS, NDP and SLC4A11 in patients with isolated Peters anomaly. PMID:25182519

Weh, Eric; Reis, Linda M; Happ, Hannah C; Levin, Alex V; Wheeler, Patricia G; David, Karen L; Carney, Erin; Angle, Brad; Hauser, Natalie; Semina, Elena V

2014-12-01

115

Learning Semantic Query Suggestions  

NASA Astrophysics Data System (ADS)

An important application of semantic web technology is recognizing human-defined concepts in text. Query transformation is a strategy often used in search engines to derive queries that are able to return more useful search results than the original query and most popular search engines provide facilities that let users complete, specify, or reformulate their queries. We study the problem of semantic query suggestion, a special type of query transformation based on identifying semantic concepts contained in user queries. We use a feature-based approach in conjunction with supervised machine learning, augmenting term-based features with search history-based and concept-specific features. We apply our method to the task of linking queries from real-world query logs (the transaction logs of the Netherlands Institute for Sound and Vision) to the DBpedia knowledge base. We evaluate the utility of different machine learning algorithms, features, and feature types in identifying semantic concepts using a manually developed test bed and show significant improvements over an already high baseline. The resources developed for this paper, i.e., queries, human assessments, and extracted features, are available for download.

Meij, Edgar; Bron, Marc; Hollink, Laura; Huurnink, Bouke; de Rijke, Maarten

116

Continental magnetic anomaly constraints on continental reconstruction  

NASA Technical Reports Server (NTRS)

Crustal magnetic anomalies mapped by the MAGSAT satellite for North and South America, Europe, Africa, India, Australia and Antarctica and adjacent marine areas were adjusted to a common elevation of 400 km and differentially reduced to the radial pole of intensity 60,000 nT. These radially polarized anomalies are normalized for differential inclination, declination and intensity effects of the geomagnetic field, so that in principle they directly reflected the geometric and magnetic polarization attributes of sources which include regional petrologic variations of the crust and upper mantle, and crustal thickness and thermal perturbations. Continental anomalies demonstrate remarkably detailed correlation of regional magnetic sources across rifted margins when plotted on a reconstruction of Pangea. Accordingly, they suggest further fundamental constraints on the geologic evolution of the continents and their reconstructions.

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

1985-01-01

117

Venus - Ishtar gravity anomaly  

NASA Technical Reports Server (NTRS)

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.

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

1984-01-01

118

Fetal cardiac anomalies  

Microsoft Academic Search

Fetal cardiac anomalies are increasingly identified during regular obstetric scanning. About 21000 pregnancies will have an abnormality of the four chamber view and a further 11000 will have an abnormality of the great arteries. These cases can then be referred to the specialist in fetal cardiology for further evaluation and counselling. There is a higher rate of chromosomal and other

Lindsey D. Allan

1996-01-01

119

Integrated geophysical investigations for the delineation of source and subsurface structure associated with hydro-uranium anomaly: A case study from South Purulia Shear Zone (SPSZ), India  

NASA Astrophysics Data System (ADS)

South Purulia Shear Zone (SPSZ) is an important region for prospecting of uranium mineralization. Geological studies and hydro-uranium anomaly suggest the presence of Uranium deposit around Raghunathpur village which lies about 8 km north of SPSZ. However, detailed geophysical investigations have not been carried out in this region for investigation of uranium mineralization. Since surface signature of uranium mineralization is not depicted near the location, a deeper subsurface source is expected for hydro uranium anomaly. To delineate the subsurface structure and to investigate the origin of hydro-uranium anomaly present in the area, Vertical Electrical Sounding (VES) using Schlumberger array and Gradient Resistivity Profiling (GRP) were performed at different locations along a profile perpendicular to the South Purulia Shear Zone. Apparent resistivity computed from the measured sounding data at various locations shows a continuously increasing trend. As a result, conventional apparent resistivity data is not able to detect the possible source of hydro uranium anomaly. An innovative approach is applied which depicts the apparent conductivity in the subsurface revealed a possible connection from SPSZ to Raghunathpur. On the other hand resistivity profiling data suggests a low resistive zone which is also characterized by low Self-Potential (SP) anomaly zone. Since SPSZ is characterized by the source of uranium mineralization; hydro-uranium anomaly at Raghunathpur is connected with the SPSZ. The conducting zone has been delineated from SPSZ to Raghunathpur at deeper depths which could be uranium bearing. Since the location is also characterized by a low gravity and high magnetic anomaly zone, this conducting zone is likely to be mineralized zone. Keywords: Apparent resistivity; apparent conductivity; Self Potential; Uranium mineralization; shear zone; hydro-uranium anomaly.

Sharma, S. P.; Biswas, A.

2012-12-01

120

Thermophysical property anomalies of Baltic seawater  

NASA Astrophysics Data System (ADS)

While the thermodynamic properties of Standard Seawater are very well known, the quantitative effect of sea salt composition anomalies on various properties is difficult to estimate since comprehensive lab experiments with the various natural waters are scarce. Coastal and estuarine waters exhibit significant anomalies which also influence to an unknown amount the routine salinity calculation from conductivity measurements. Recent numerical models of multi-component aqueous electrolytes permit the simulation of physical chemical properties of seawater with variable solute composition. In this paper, the FREZCHEM model is used to derive a Gibbs function for Baltic seawater, and the LSEA_DELS model to provide estimates for the conductivity anomaly relative to Standard Seawater. From additional information such as direct density measurements or empirical salinity anomaly parameterisation, the quantitative deviations of properties between Baltic and Standard Seawater are calculated as functions of salinity and temperature. While several quantities show anomalies that are comparable with their measurement uncertainties and do not demand special improvement, others exhibit more significant deviations from Standard Seawater properties. In particular density and sound speed turn out to be significantly sensitive to the presence of anomalous solute. Suitable general correction methods are suggested to be applied to Baltic Sea samples with known Practical Salinity and, optionally, directly determined density.

Feistel, R.; Marion, G. M.; Pawlowicz, R.; Wright, D. G.

2010-06-01

121

Thermophysical property anomalies of Baltic seawater  

NASA Astrophysics Data System (ADS)

While the thermodynamic properties of Standard Seawater are very well known, the quantitative effect of sea salt composition anomalies on various properties is difficult to estimate since comprehensive lab experiments with the various natural waters are scarce. Coastal and estuarine waters exhibit significant anomalies which also influence to an unknown amount the routine salinity calculation from conductivity measurements. Recent numerical models of multi-component aqueous electrolytes permit the simulation of physical chemical properties of seawater with variable solute composition. In this paper, the FREZCHEM model is used to derive a Gibbs function for Baltic seawater, and the LSEA_DELS model to provide estimates for the conductivity anomaly relative to Standard Seawater. From additional information such as direct density measurements or empirical salinity anomaly parameterisation, the quantitative deviations of properties between Baltic and Standard Seawater are calculated as functions of salinity and temperature. While several quantities show anomalies that are comparable with their measurement uncertainties and do not demand special improvement, others exhibit more significant deviations from Standard Seawater properties. In particular density and sound speed turn out to be significantly sensitive to the presence of anomalous solute. Suitable general correction methods are suggested to be applied to Baltic Sea samples with known Practical Salinity and, optionally, directly determined density.

Feistel, R.; Marion, G. M.; Pawlowicz, R.; Wright, D. G.

2010-11-01

122

Genetics Home Reference: Peters anomaly  

MedlinePLUS

... the individuals affected with Peters anomaly have low vision early in life and about a quarter are legally blind. Due to a lack of visual stimulation, some individuals develop "lazy eye" (amblyopia). Peters anomaly ...

123

Yearly Arctic Temperature Anomaly  

NSDL National Science Digital Library

This animation shows the yearly temperature anomaly over the Arctic region from 1981-82 through 2002-03. Years run from August 1 through July 31. Blue hues indicate cooling regions; red hues depict warming. Light regions indicate less change while darker regions indicate more. The temperature scale used ranges from -7.0 to +7.0 degrees Celsius in increments of .25 degrees. (See color bar below)

Starr, Cindy; Comiso, Josefino

2003-10-23

124

Anomaly, impulsivity, and addiction  

Microsoft Academic Search

There are two behavioral approaches to addiction: rational and irrational. The rational approach assumes that addicts have higher time preference rates and lower risk-aversion coefficients—parameters that are interpreted as impulsive preferences. On the other hand, the irrational approach argues that addiction is a consequence of anomalies such as non-expected utility and hyperbolically discounted utility. This paper integrates these two approaches

Takanori Ida

2010-01-01

125

Pathogenesis of Vascular Anomalies  

PubMed Central

Vascular anomalies are localized defects of vascular development. Most of them occur sporadically, i.e. there is no familial history of lesions, yet in a few cases clear inheritance is observed. These inherited forms are often characterized by multifocal lesions that are mainly small in size and increase in number with patient’s age. On the basis of these inherited forms, molecular genetic studies have unraveled a number of inherited mutations giving direct insight into the pathophysiological cause and the molecular pathways that are implicated. Genetic defects have been identified for hereditary haemorrhagic telangiectasia (HHT), inherited cutaneomucosal venous malformation (VMCM), glomuvenous malformation (GVM), capillary malformation - arteriovenous malformation (CM-AVM), cerebral cavernous malformation (CCM) and some isolated and syndromic forms of primary lymphedema. We focus on these disorders, the implicated mutated genes and the underlying pathogenic mechanisms. We also call attention to the concept of Knudson’s double-hit mechanism to explain incomplete penetrance and the large clinical variation in expressivity of inherited vascular anomalies. This variability renders the making of correct diagnosis of the rare inherited forms difficult. Yet, the identification of the pathophysiological causes and pathways involved in them has had an unprecedented impact on our thinking of their etiopathogenesis, and has opened the doors towards a more refined classification of vascular anomalies. It has also made it possible to develop animal models that can be tested for specific molecular therapies, aimed at alleviating the dysfunctions caused by the aberrant genes and proteins. PMID:21095468

Boon, Laurence M.; Ballieux, Fanny; Vikkula, Miikka

2010-01-01

126

Maternal water consumption during pregnancy and congenital cardiac anomalies  

SciTech Connect

This case-control study, conducted in a California county that had a local incident of water contamination in 1981, investigated the relation between a mother's reported consumption of tap water during pregnancy and congenital cardiac anomalies in their offspring born during 1981-1983. Data were obtained from telephone interviews with 145 mothers of children born with a severe cardiac anomaly and 176 mothers of children born without such an anomaly. A positive association between a mother's consumption of home tap water during the first trimester of pregnancy and cardiac anomalies in her infant was unrelated to the incident of water contamination, the mother's race, or her educational level. A negative relation was found between a mother's use of bottled water and cardiac anomalies among the infants. These findings corresponded primarily to births in 1981. These data could not fully distinguish between a potential causal agent in the water and differential reporting of exposure by study subjects.

Shaw, G.M.; Swan, S.H.; Harris, J.A.; Malcoe, L.H. (California Birth Defects Monitoring Program, Emeryville (USA))

1990-05-01

127

Turtle Carapace Anomalies: The Roles of Genetic Diversity and Environment  

PubMed Central

Background Phenotypic anomalies are common in wild populations and multiple genetic, biotic and abiotic factors might contribute to their formation. Turtles are excellent models for the study of developmental instability because anomalies are easily detected in the form of malformations, additions, or reductions in the number of scutes or scales. Methodology/Principal Findings In this study, we integrated field observations, manipulative experiments, and climatic and genetic approaches to investigate the origin of carapace scute anomalies across Iberian populations of the European pond turtle, Emys orbicularis. The proportion of anomalous individuals varied from 3% to 69% in local populations, with increasing frequency of anomalies in northern regions. We found no significant effect of climatic and soil moisture, or climatic temperature on the occurrence of anomalies. However, lower genetic diversity and inbreeding were good predictors of the prevalence of scute anomalies among populations. Both decreasing genetic diversity and increasing proportion of anomalous individuals in northern parts of the Iberian distribution may be linked to recolonization events from the Southern Pleistocene refugium. Conclusions/Significance Overall, our results suggest that developmental instability in turtle carapace formation might be caused, at least in part, by genetic factors, although the influence of environmental factors affecting the developmental stability of turtle carapace cannot be ruled out. Further studies of the effects of environmental factors, pollutants and heritability of anomalies would be useful to better understand the complex origin of anomalies in natural populations. PMID:21533278

Velo-Antón, Guillermo; Becker, C. Guilherme; Cordero-Rivera, Adolfo

2011-01-01

128

Physicochemical isotope anomalies  

SciTech Connect

Isotopic composition of refractory elements can be modified, by physical processes such as distillation and sputtering, in unexpected patterns. Distillation enriches the heavy isotopes in the residue and the light isotopes in the vapor. However, current models appear to be inadequate to describe the detailed mass dependence, in particular for large fractionations. Coarse- and fine-grained inclusions from the Allende meteorite exhibit correlated isotope effects in Mg both as mass-dependent fractionation and residual anomalies. This isotope pattern can be duplicated by high temperature distillation in the laboratory. A ubiquitous property of meteoritic inclusions for Mg as well as for most of the other elements, where measurements exist, is mass-dependent fractionation. In contrast, terrestrial materials such as microtektites, tektite buttons as well as lunar orange and green glass spheres have normal Mg isotopic composition. A subset of interplanetary dust particles labelled as chondritic aggregates exhibit excesses in {sup 26}Mg and deuterium anomalies. Sputtering is expected to be a dominant mechanism in the destruction of grains within interstellar dust clouds. An active proto-sun as well as the present solar-wind and solar-flare flux are of sufficient intensity to sputter significant amounts of material. Laboratory experiments in Mg show widespread isotope effects including residual {sup 26}Mg excesses and mass dependent fractionation. It is possible that the {sup 26}Mg excesses in interplanetary dust is related to sputtering by energetic solar-wind particles. The implication if the laboratory distillation and sputtering effects are discussed and contrasted with the anomalies in meteoritic inclusions the other extraterrestrial materials the authors have access to.

Esat, T.M. (Australian National Univ., Canberra)

1988-06-01

129

Gravitational Anomalies in the Solar System?  

E-print Network

Mindful of the anomalous perihelion precession of Mercury discovered by U. Le Verrier in the second half of the nineteenth century and its successful explanation by A. 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 bodies 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 cumulative science, as shown to us by the discovery of Neptune in the first half of the nineteenth century. 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; and h) The anomalous secular increase of the astronomical unit

Lorenzo Iorio

2015-01-21

130

Gravitational Anomalies in the Solar System?  

E-print Network

Mindful of the anomalous perihelion precession of Mercury discovered by U. Le Verrier in the second half of the nineteenth century and its successful explanation by A. 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 bodies 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 cumulative science, as shown to us by the discovery of Neptune in the first half of the nineteenth century. 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; and h) The anomalous secular increase of the astronomical unit

Lorenzo Iorio

2014-12-21

131

Numerical Shockwave Anomalies  

NASA Astrophysics Data System (ADS)

The reliable simulation of shockwaves is critical in the prediction and study of many phenomena, where abrupt changes in material properties due to shockwaves can greatly affect regions of interest and activate physical mechanisms. When a physical shockwave is formed, it moves through the flow with a certain speed, having some finite width determined by physical dissipation until it encounters some event in its path. For numerical shockwaves, however, a numerical width is enforced, often much greater than the physical width. With this numerical width comes the formation of intermediate states having no direct physical interpretation. Even as the mesh is refined, these intermediate states do not go away; they simply occupy less space. The existence of intermediate states does raise some doubt, however, about how closely a captured shockwave may emulate an ideal discontinuous shockwave, or a real physical one. There are in fact several types of error associated with intermediate shock states such as errors in shock position, spurious waves, or unstable shock behavior. These errors can be classified as numerical shockwave anomalies; they are numerical artifacts formed due to the presence of captured shockwaves within the flow solution. Each numerical shockwave anomaly is directly related to the nonlinearity of the jump conditions and to a resulting ambiguity in sub-cell shock position in a stationary shock. Two new flux functions are developed that do not have this ambiguity. On all of the shock anomalies in one-dimension, both flux functions show improvement on existing methods without smearing or diffusing the shock. They are also shown to perform adequately within a second-order framework and on two-dimensional problems, important for the practicality of the method. While they are still susceptible to many of the problems that occur in Roe's Riemann solver and several other known issues, these methods serve to validate the philosophy and approach taken in this thesis: by enforcing a linear shock structure and unambiguous sub-cell shock position, numerical shockwave anomalies are dramatically reduced.

Zaide, Daniel Wei-Ming

132

ANALYZING THE FLUX ANOMALIES OF THE LARGE-SEPARATION LENSED QUASAR SDSS J1029+2623  

SciTech Connect

Using a high-resolution radio image, we successfully resolve the two-fold image components B and C of the quasar lens system SDSS J1029+2623. The flux anomalies associated with these two components in the optical regime persist, albeit less strongly, in our radio observations suggesting that the cluster must be modeled by something more than a single central potential. We argue that placing substructure close to one of the components can account for a flux anomaly with negligible changes in the component positions. Our best-fit model has a substructure mass of {approx}10{sup 9} M{sub sun} up to the mass-sheet degeneracy, located roughly 0.''1 west and 0.''1 north of component B. We demonstrate that a positional offset between the centers of the source components can explain the differences between the optical and radio flux ratios.

Kratzer, Rachael M.; Richards, Gordon T.; Goldberg, David M. [Department of Physics, Drexel University, Philadelphia, PA 19104 (United States); Oguri, Masamune [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Kochanek, Christopher S. [Department of Astronomy, Ohio State University, Columbus, OH 43210 (United States); Hodge, Jacqueline A.; Becker, Robert H. [Department of Physics, University of California, Davis, CA 95616 (United States); Inada, Naohisa [Research Center for the Early Universe, School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

2011-02-10

133

Determination of mean gravity anomalies in the Taiwan Island  

NASA Technical Reports Server (NTRS)

The fitting and proper regression coefficients were made of one hundred seventeen 10 x 10' blocks with observed gravity data and corresponding elevation in the Taiwan Island. To compare five different predicted models, and the proper one for the mean gravity anomalies were determined. The predicted gravity anomalies of the non-observed gravity blocks were decided when the coefficients obtained through the model with the weighted mean method. It was suggested that the mean gravity anomalies of 10 x 10' blocks should be made when comprehensive the observed and predicted data.

Chang, Ruey-Gang

1989-01-01

134

A major geothermal anomaly in the Gulf of California  

USGS Publications Warehouse

We have mapped a 3-km wide, high heat flow anomaly with a maximum value of 30 ??calorie cm -2 s-1 within a zone of seafloor extension in the central Gulf of California. From seismic reflection data and thermal modelling we suggest that the anomaly is caused by a 1-km wide basaltic intrusion which is roughly 100 m deep and less than 18,000 yr old. ?? 1975 Nature Publishing Group.

Lawver, L.A.; Williams, D.L.; Von Herzen, R. P.

1975-01-01

135

SHEAR WAVE VELOCITY FIELD TO DETECT ANOMALIES UNDER ASPHALT  

Microsoft Academic Search

Non-invasive mapping of anomalies beneath asphalt at depths from 2 m to as deep as 50 m has been successful using MASW in a variety of near-surface settings. Anomalies that include fracture zones within bedrock, dissolution\\/potential subsidence features, voids associated with old mine works, and erosional channels eched into the bedrock surface have been effectively identified in the shear wave

Richard D. Miller; Jianghai Xia; Choon Byong Park; Julian Ivanov

2001-01-01

136

System for closure of a physical anomaly  

DOEpatents

Systems for closure of a physical anomaly. Closure is accomplished by a closure body with an exterior surface. The exterior surface contacts the opening of the anomaly and closes the anomaly. The closure body has a primary shape for closing the anomaly and a secondary shape for being positioned in the physical anomaly. The closure body preferably comprises a shape memory polymer.

Bearinger, Jane P; Maitland, Duncan J; Schumann, Daniel L; Wilson, Thomas S

2014-11-11

137

Anomaly Structure of Regularized Supergravity  

NASA Astrophysics Data System (ADS)

On-shell Pauli-Villars regularization of the one-loop divergences of supergravity theories is used to study the anomaly structure of supergravity and the cancellation of field theory anomalies under a U (1 ) gauge transformation and under the T -duality group of modular transformations in effective supergravity theories with three Kähler moduli Ti obtained from orbifold compactification of the weakly coupled heterotic string. This procedure requires constraints on the chiral matter representations of the gauge group that are consistent with known results from orbifold compactifications. Pauli-Villars (PV) regulator fields allow for the cancellation of all quadratic and logarithmic divergences, as well as most linear divergences. If all linear divergences were canceled, the theory would be anomaly free, with noninvariance of the action arising only from Pauli-Villars masses. However there are linear divergences associated with nonrenormalizable gravitino/gaugino interactions that cannot be canceled by PV fields. The resulting chiral anomaly forms a supermultiplet with the corresponding conformal anomaly, provided the ultraviolet cutoff has the appropriate field dependence, in which case total derivative terms, such as Gauss-Bonnet, do not drop out from the effective action. The anomalies can be partially canceled by the four-dimensional version of the Green-Schwarz mechanism, but additional counterterms, and/or a more elaborate set of Pauli-Villars fields and couplings, are needed to cancel the full anomaly, including D -term contributions to the conformal anomaly that are nonlinear in the parameters of the anomalous transformations.

Butter, Daniel; Gaillard, Mary K.

2015-01-01

138

Barium and neodymium isotopic anomalies in the Allende meteorite  

NASA Technical Reports Server (NTRS)

The discovery of Ba and Nd isotopic anomalies in two inclusions from the Allende meteorite is reported. The inclusions are Ca-Al-rich objects typical of the type considered as high-temperature condensation products in the solar nebula and contain distinctive Mg and O isotopic anomalies of the FUN (mass Fractionation, Unknown Nuclear processes) type. Mass-spectrometry results are discussed which show that inclusion C1 has anomalies in Ba at masses 134 and 136, while inclusion EK1-4-1 exhibits large marked negative anomalies at 130, 132, 134, and 136, as well as a positive anomaly at 137. It is also found that inclusion EK1-4-1 shows marked negative anomalies in Nd at masses 142, 146, 148, and 150, in addition to a positive anomaly at 145. These isotopic shifts are attributed to addition of r-process nuclei rather than mass fractionation. It is suggested that an onion-shell supernova explosion followed by injection into the solar nebula is the most likely generic model that may explain the observations.

Mcculloch, M. T.; Wasserburg, G. J.

1978-01-01

139

Nesting of thermodynamic, structural, and dynamic anomalies in liquid silicon  

NASA Astrophysics Data System (ADS)

Anomalous behaviour in density, diffusivity, and structural order is investigated for silicon modeled by the Stillinger-Weber potential by performing molecular dynamics simulations. As previously reported in the case of water [J. R. Errington and P. G. Debenedetti, Nature (London) 409, 318 (2001)] and silica [M. S. Shell, P. G. Debenedetti, and A. Z. Panagiotopoulos, Phys. Rev. E 66, 011202 (2002)], a cascading of thermodynamic, dynamic, and structural anomalous regions is also observed in liquid silicon. The region of structural anomaly includes the region of diffusivity anomaly, which in turn encompasses the region of density anomaly (which is unlike water but similar to silica). In the region of structural anomaly, a tight correlation between the translational and tetrahedrality order parameter is found, but the correlation is weaker when a local orientational order parameter (q3) is used as a measure of tetrahedrality. The total excess entropy and the pair correlation entropy are computed across the phase diagram and the correlation between the excess entropy and the regions of anomalies in the phase diagram of liquid silicon is examined. Scaling relations associating the excess entropy with the diffusion coefficient show considerable deviation from the quasi-universal behaviour observed in hard-sphere and Lennard-Jones liquids and some liquid metals. Excess entropy based criteria for diffusivity and structural anomalies fail to capture the observed regions of anomaly.

Vasisht, Vishwas V.; Mathew, John; Sengupta, Shiladitya; Sastry, Srikanth

2014-09-01

140

Nesting of thermodynamic, structural, and dynamic anomalies in liquid silicon.  

PubMed

Anomalous behaviour in density, diffusivity, and structural order is investigated for silicon modeled by the Stillinger-Weber potential by performing molecular dynamics simulations. As previously reported in the case of water [J. R. Errington and P. G. Debenedetti, Nature (London) 409, 318 (2001)] and silica [M. S. Shell, P. G. Debenedetti, and A. Z. Panagiotopoulos, Phys. Rev. E 66, 011202 (2002)], a cascading of thermodynamic, dynamic, and structural anomalous regions is also observed in liquid silicon. The region of structural anomaly includes the region of diffusivity anomaly, which in turn encompasses the region of density anomaly (which is unlike water but similar to silica). In the region of structural anomaly, a tight correlation between the translational and tetrahedrality order parameter is found, but the correlation is weaker when a local orientational order parameter (q3) is used as a measure of tetrahedrality. The total excess entropy and the pair correlation entropy are computed across the phase diagram and the correlation between the excess entropy and the regions of anomalies in the phase diagram of liquid silicon is examined. Scaling relations associating the excess entropy with the diffusion coefficient show considerable deviation from the quasi-universal behaviour observed in hard-sphere and Lennard-Jones liquids and some liquid metals. Excess entropy based criteria for diffusivity and structural anomalies fail to capture the observed regions of anomaly. PMID:25273445

Vasisht, Vishwas V; Mathew, John; Sengupta, Shiladitya; Sastry, Srikanth

2014-09-28

141

Expanding the clinical spectrum of ocular anomalies in Noonan syndrome: Axenfeld-anomaly in a child with PTPN11 mutation.  

PubMed

Ocular anomalies have been frequently reported in Noonan syndrome. Anterior segment anomalies have been described in 57% of PTPN11 positive patients, with the most common findings being corneal changes and in particular, prominent corneal nerves and cataracts. We report on a neonate with a confirmed PTPN11 mutation and ocular findings consistent with Axenfeld anomaly. The patient initially presented with non-immune hydrops and subsequently developed hypertrophic cardiomyopathy and dysmorphic features typical of Noonan syndrome. While a pathogenic mutation in PTPN11 was confirmed, prior testing for the two common genes associated with Axenfeld-Rieger syndrome, PITX2, and FOXC1 was negative. This finding expands the spectrum of anterior chamber anomalies seen in Noonan syndrome and perhaps suggests a common neural crest related mechanism that plays a critical role in the development of the eye and other organs. © 2014 Wiley Periodicals, Inc. PMID:25425531

Guerin, Andrea; So, Joyce; Mireskandari, Kamiar; Jougeh-Doust, Soghra; Chisholm, Caitlin; Klatt, Regan; Richer, Julie

2015-02-01

142

Gravitational anomaly and transport phenomena.  

PubMed

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. PMID:21797593

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

2011-07-01

143

Evaluation of anomalies in GLDAS-1996 dataset.  

PubMed

Global Land Data Assimilation System (GLDAS) data are widely used for land-surface flux simulations. Therefore, the simulation accuracy using GLDAS dataset is largely contingent upon the accuracy of the GLDAS dataset. It is found that GLDAS land-surface model simulated runoff exhibits strong anomalies for 1996. These anomalies are investigated by evaluating four GLDAS meteorological forcing data (precipitation, air temperature, downward shortwave radiation and downward longwave radiation) in six large basins across the world (Danube, Mississippi, Yangtze, Congo, Amazon and Murray-Darling basins). Precipitation data from the Global Precipitation Climatology Centre (GPCC) are also compared with GLDAS forcing precipitation data. Large errors and lack of monthly variability in GLDAS-1996 precipitation data are the main sources for the anomalies in the simulated runoff. The impact of the precipitation data on simulated runoff for 1996 is investigated with the Community Atmosphere Biosphere Land Exchange (CABLE) land-surface model in the Yangtze basin, for which area high-quality local precipitation data are obtained from the China Meteorological Administration (CMA). The CABLE model is driven by GLDAS daily precipitation data and CMA daily precipitation, respectively. The simulated daily and monthly runoffs obtained from CMA data are noticeably better than those obtained from GLDAS data, suggesting that GLDAS-1996 precipitation data are not so reliable for land-surface flux simulations. PMID:23579825

Zhou, Xinyao; Zhang, Yongqiang; Yang, Yonghui; Yang, Yanmin; Han, Shumin

2013-01-01

144

Origin of conductivity anomalies in the asthenosphere  

NASA Astrophysics Data System (ADS)

Electrical conductivity anomalies with anisotropy parallel to the plate motion have been observed beneath the oceanic lithosphere by electromagnetic studies (e.g., Evans et al., 2005; Baba et al., 2010; Naif et al., 2013). Electrical conductivity of the oceanic asthenosphere at ~100 km depth is very high, about 10-2 to 10-1 S/m. This zone is also known in seismology as the low velocity zone. Since Karato (1990) first suggested that electrical conductivity is sensitive to water content in NAMs, softening of asthenosphere has been regarded as a good indicator for constraining the distribution of water. There are two difficulties to explain the observed conductivity features in the asthenosphere. Recent publications on electrical conductivity of hydrous olivine suggested that olivine with the maximum soluble H2O content at the top of the asthenosphere has much lower conductivity less than 0.1 S/m (e.g., Yoshino et al., 2006; 2009a; Poe et al., 2010; Du Frane and Tyburczy, 2012; Yang, 2012), which is a typical value of conductivity anomaly observed in the oceanic mantle. Partial melting has been considered as an attractive agent for substantially raising the conductivity in this region (Shankland and Waff, 1977), because basaltic melt has greater electrical conductivity (> 100.5 S/m) and high wetting properties. However, dry mantle peridotite cannot reach the solidus temperature at depth 100 km. Volatile components can dramatically reduce melting temperature, even if its amount is very small. Recent studies on conductivity measurement of volatile-bearing melt suggest that conductivity of melt dramatically increases with increasing volatile components (H2O: Ni et al., 2010a, b; CO2: Gaillard et al., 2008; Yoshino et al., 2010; 2012a). Because incipient melt includes higher amount of volatile components, conductivity enhancement by the partial melt is very effective at temperatures just above that of the volatile-bearing peridotite solidus. In this study, the electrical conductivity of peridotite with trace amount of volatile phases was measured in single crystal olivine capsule to protect escape of water from the sample at 3 GPa. The conductivity values were significantly higher than those of dry peridotite, suggesting that the observed conductivity anomalies at the asthenosphere are caused by a presence of trace amount of volatile component in fluid or melt. On the other hand, conductivity of partial molten peridotite measured under shear showed that the conductivity parallel to the shear direction becomes one order of magnitude higher than that normal direction. These observations suggest that partial melting can explain softening and the observed geophysical anomalies of asthenosphere.

Yoshino, T.; Zhang, B.

2013-12-01

145

Strong phonon anomalies and Fermi surface nesting of simple cubic Polonium  

NASA Astrophysics Data System (ADS)

The unknown lattice dynamics of simple cubic Polonium is calculated using first-principles density-functional perturbation theory with pseudopotentials and a plane-wave basis set. We notice several phonon anomalies, in particular along major symmetry directions namely M-R, R-?, ?-M, M-X, and X-?. The analysis of the Fermi surface strongly suggests that the observed phonon anomalies are Kohn anomalies arising from strong Fermi surface nesting.

Belabbes, A.; Zaoui, A.; Ferhat, M.

2010-12-01

146

A {open_quotes}balanced{close_quotes} Y:16 translocation with the Y breakpoint just proximal to the Yq heterochromatin boundary associated with Turner-like neonatal lymphedema suggests the location of a potential anti-Turner gene  

SciTech Connect

A male patient with Turner-like hydrops in the newborn period (Bonnevie-Ullrich syndrome) was studied. The extensive nucchal cystic hygroma and hydrops resolved over several weeks. The karyotype was 46,X,t(Y;16)(q11.2;q24). The paternal karyotype was normal. Chromosome painting with the heterochromatic long arm repeat DYZ2 disclosed that all the hybridization was on the derivative 16. This was confirmed by chromosome painting with DYZ1, the other major Y long arm heterochromatic repeat, and DYZ3, the Y alphoid, centromeric repeat, which showed chromosomal separation of the 2 stained regions. A {open_quotes}FISHing trip{close_quotes} was performed using the Y YAC contig created in Dr. David Page`s laboratory. This disclosed 2 YACs located just proximal to the Y heterochromatin which {open_quotes}jumped{close_quotes} the translocation. The recent discovery of a candidate gene for the azoospermia factor (AZF) in this region suggests the possibility that there are several Y-expressed genes adjacent to the heterochromatin boundary as there are near the pseudoautosomal boundary.

Erickson, R.P.; Hudgins, L. [Univ. of Arizona, Tucson, AZ (United States); Stone, J.F. [Southwest Biomedical Research Institute, Scottsdale, AZ (United States)] [and others

1994-09-01

147

Detection of anomalies in radio tomography of asteroids: Source count and forward errors  

NASA Astrophysics Data System (ADS)

The purpose of this study was to advance numerical methods for radio tomography in which asteroid's internal electric permittivity distribution is to be recovered from radio frequency data gathered by an orbiter. The focus was on signal generation via multiple sources (transponders) providing one potential, or even essential, scenario to be implemented in a challenging in situ measurement environment and within tight payload limits. As a novel feature, the effects of forward errors including noise and a priori uncertainty of the forward (data) simulation were examined through a combination of the iterative alternating sequential (IAS) inverse algorithm and finite-difference time-domain (FDTD) simulation of time evolution data. Single and multiple source scenarios were compared in two-dimensional localization of permittivity anomalies. Three different anomaly strengths and four levels of total noise were tested. Results suggest, among other things, that multiple sources can be necessary to obtain appropriate results, for example, to distinguish three separate anomalies with permittivity less or equal than half of the background value, relevant in recovery of internal cavities.

Pursiainen, S.; Kaasalainen, M.

2014-09-01

148

An unusual ultrasonographic manifestation of a fetal Ebstein anomaly  

PubMed Central

An Ebstein anomaly is a rare congenital heart defect defined by an inferior displacement of the septal and posterior leaflets of the tricuspid valve from the tricuspid annulus. This anomaly shows various ultrasonographic manifestations, thus making the prenatal diagnosis sometimes difficult. We here report a rare case of an Ebstein anomaly which was prenatally suspected as the absence of the tricuspid valve with functional pulmonary atresia because of non-visible tricuspid leaflets on an echocardiograph at 24 weeks of gestation. An emergency cesarean section was performed at 35 weeks of gestation as fetal hydrops were seen on a follow-up scan. Postnatal surgery confirmed Ebstein anomaly type-D which demonstrates an almost complete atrialization of the right ventricle with the exception of a small and infundibular component. Because of its rarity, prenatal findings of a type-D Ebstein anomaly have not been reported previously. We suggest from this first such case report that this anomaly should be considered as a possible diagnosis when the tricuspid leaflets are not well visualized. PMID:25469344

Cha, Min-Young; Lee, Mi-Young; Woo, Kyung-Hee; Shim, Jae-Yoon

2014-01-01

149

Interpretation of magnetic anomalies over the Grenada Basin  

NASA Astrophysics Data System (ADS)

The Grenada Basin is a back arc basin located near the eastern border of the Caribbean Plate. The basin is bounded on the west by the north-south trending Aves Ridge (a remnant island arc) and on the east by the active Lesser Antilles island arc. Although this physiography suggests that east-west extension formed the basin, magnetic anomalies over the basin exhibit predominantly east-west trends. If the observed magnetic anomalies over the basin are produced by seafloor spreading, then the orientation of extension is complex. Extension in back arc basins is roughly normal to the trench, although some basins exhibit oblique extension. Present models for the formation of the Grenada Basin vary from north-south extension through northeast-southwest extension to east-west extension. An interpretation of magnetic anomalies over the Grenada Basin supports basin development by nearly east-west extension. Low amplitude magnetic anomaly trends subparallel to the island arc magnetic anomaly trends over the southern part of the basin and the results of forward three-dimensional (3-D) magnetic modeling are consistent with this conclusion. Late Cenozoic tectonic movements may have been responsible for disrupting the magnetic signature over the northern part of the basin. On the basis of our 3-D analysis, we attribute the prominent east-west trending anomalies of the Grenada Basin to fracture zones formed during seafloor spreading at low latitude. This east-west trend is not interpreted as indicating north-south extension of the basin.

Bird, Dale E.; Hall, Stuart A.; Casey, John F.; Millegan, Patrick S.

1993-10-01

150

Remote detection of geochemical soil anomalies  

USGS Publications Warehouse

This paper describes a preliminary experiment that was made to compare the spectral reflectance from trees growing in soil over a mineral deposit with reflectance from trees of the same species growing in a nearby unmineralized area. Although the measurements were made on a relatively small number of trees, some significant differences were obtained and the over-all results are encouraging enough to warrant additional studies. Preliminary results suggest that measurement of spectral reflectance may become a dramatic new way of detecting geochemical soil anomalies by remote means in tree-covered areas.

Canney, F.C.

1970-01-01

151

A New Methodology for Early Anomaly Detection of BWR Instabilities  

SciTech Connect

The objective of the performed research is to develop an early anomaly detection methodology so as to enhance safety, availability, and operational flexibility of Boiling Water Reactor (BWR) nuclear power plants. The technical approach relies on suppression of potential power oscillations in BWRs by detecting small anomalies at an early stage and taking appropriate prognostic actions based on an anticipated operation schedule. The research utilizes a model of coupled (two-phase) thermal-hydraulic and neutron flux dynamics, which is used as a generator of time series data for anomaly detection at an early stage. The model captures critical nonlinear features of coupled thermal-hydraulic and nuclear reactor dynamics and (slow time-scale) evolution of the anomalies as non-stationary parameters. The time series data derived from this nonlinear non-stationary model serves as the source of information for generating the symbolic dynamics for characterization of model parameter changes that quantitatively represent small anomalies. The major focus of the presented research activity was on developing and qualifying algorithms of pattern recognition for power instability based on anomaly detection from time series data, which later can be used to formulate real-time decision and control algorithms for suppression of power oscillations for a variety of anticipated operating conditions. The research being performed in the framework of this project is essential to make significant improvement in the capability of thermal instability analyses for enhancing safety, availability, and operational flexibility of currently operating and next generation BWRs.

Ivanov, K. N.

2005-11-27

152

Satellite Geopotential Anomaly Constraints for the Crust of the Greenland-Iceland Region  

NASA Technical Reports Server (NTRS)

Satellite magnetometer observations of the Greenland-Iceland region compare quite well with lower altitude data. The satellite magnetic data suggest magnetically enhanced crust was emplaced by the Iceland Plume. Crustal thicknesses, which may be more than 30 km for the Greenland-Scotland Ridge, were obtained from inversion of the compensating terrain gravity effects that were estimated by spectral correlation analysis of the free-air gravity anomalies and terrain gravity effects. Regional magnetic anomaly maxima overlie possible thickened crust from eastern Iceland to the Greenland Coast. The Iceland-Faroe Ridge may involve thinner crust than the Greenland-Iceland portion of the Greenland-Scotland Ridge. The gravity derived crustal model exceeds a 0.7 correlation with available seismic estimates. In thermally active areas our gravity Moho estimates are systematically deeper than the seismic estimates suggesting local density reductions of the underlying lower crust/upper mantle. In south central Greenland, on the other hand, the gravity Moho estimates are shallower than seismic estimates to suggest a local enhancement of the lower crust/upper mantle density. The dichotomous crust of the Greenland-Iceland and Iceland-Faroe Ridges suggests unequal crustal development by the Iceland Plume and the Mid-Atlantic Ridge, where more crustal material may have been contributed to the North Atlantic Plate than the Eurasian Plate. A new thermal modeling scheme based on Poisson's relation between point pole gravity and thermal potentials allows estimation of magnetic crustal thicknesses. Subsequent magnetic anomaly inversion for susceptibility contrasts infers crustal development of the Greenland-Scotland Ridge by temporally variable pulses in plume strength.

vonFrese, R. R.; Leftwich, T. E.; Kim, H.; Taylor, Patrick T.; Kim, J.

2004-01-01

153

Maternal abetalipoproteinemia resulting in multiple fetal anomalies.  

PubMed

Abetalipoproteinemia is a rare genetic condition that results in an inability of the body to absorb dietary fats, including fat-soluble vitamins. Deficiencies of these vitamins are known to cause a wide range of clinical effects ranging from blindness to coagulopathy and neuropathy. We present the case of a child with multisystem anomalies born to a mother with abetalipoproteinemia and provide a brief review of the literature about vitamin A and fetal development. Mothers at high risk for vitamin deficiencies should be screened and counseled on the potential benefits, and risks, of vitamin supplementation. PMID:18784430

Seckeler, Michael D; Linden, Jennifer

2008-01-01

154

MAGSAT anomaly map and continental drift  

NASA Technical Reports Server (NTRS)

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.

Lemouel, J. L. (principal investigator); Galdeano, A.; Ducruix, J.

1981-01-01

155

Little SUSY hierarchy in mixed modulus-anomaly mediation  

Microsoft Academic Search

Motivated by the KKLT string compactification involving a supersymmetry-breaking uplifting potential, we examine 4D effective supergravity with a generic form of uplifting potential, focusing on the possibility that the resulting mixed modulus-anomaly mediated soft terms realize the little hierarchy between the Higgs boson masses mH and the sparticle masses mSUSY. It is noted that for some type of uplifting potential,

Kiwoon Choi; Kwang Sik Jeong; Tatsuo Kobayashi; Ken-Ichi Okumura

2006-01-01

156

Leadership Theories--Managing Practices, Challenges, Suggestions  

ERIC Educational Resources Information Center

A shortage of community college executives due to the number of retirements occurring among current leaders is predicted. An examination of three leadership theories--servant-leadership, business leadership and transformational leadership--suggests techniques for potential community college leaders. Servant-leaders focus on the needs of their…

Hawkins, Cheryl

2009-01-01

157

Current Research: Summer Reading Suggestions  

NSDL National Science Digital Library

To supplement your summer reading, NSTA's affiliates would like to suggest some recent articles on education research. These articles cover a variety of topics that include diversity, technology, and science teacher retention. The abstracts of these impor

2009-07-01

158

Anomalies of neutron field of the Earth.  

NASA Astrophysics Data System (ADS)

This work is devoted to the researches of time and spatial heterogeneity of thermal neurtron flux (Fn) density in the troposphere of the Earth. We had already received the values of thermal neutron flux density on the surface of the Earth in the European part of Russia. The large-scale monitoring of thermal neutron flux density was carried out on structural cross-section from Drake Strait in the Atlantic Ocean to the high latitudes of Arctic. We observe the increase of Fn from 44? N to 59? N, from 0,4 to 2,9 •10-3 ?/(c•c?2). The values of Fn were received in latitude Novorossiysk (0,4•10-3 n/(c•sm2)) , Moskow (0,7-1,5•10-3 n/(c•sm2)), Arhangelsk (1,3•10-3 n/(c•sm2)). High-rise dependance of the thermal neutron flux density on the surface of the Earth and in troposphere during transcontinental flights was researched. With the increasing of height from 0 to 8000 m the thermal neutron flux density rises to 180•10-3 ?/(c•c?2) The measurements were carried out in latitude of Spitsbergen. The value of thermal neutron flux density on the North pole was measured. Fn is equal to 0,7•10-3 n/(c•sm2)) 890 20/ in North latitude. Recently it has been shown, that thermal neutrons render appreciable influence on alive organisms [Matveeva and etc., 2004, Masunaga S., 2001]. Abmormal increases of thermal neutron flux density are revealed in flora biogeocenosis. Daily background Fn demonstrate the specific abnormal flares for every biocenosis or biotope long-lasting (for tens of minutes) Fn - meaning during the «flares» in biogeocenosis depends on the contains of flora community and can reach 104 n/(? m2). [Plotnikova N.V., Siroeshkin A.V., 2005]. The researches of the neutron field in the World Ocean were received at the time of transatlantic expedition by the programme of RAS «Meridian» (2006, 2008). Abnormal increasing Fn had being observed in the area of equator and between 310N to 540N and 330S to 530S Moreover, the coordinates of these anomalies coincide with the coordinates of the subequatorial and subtropical climatic zones. This anomalous increase Fn happens above, with an increase in phytoplankton biomass, the value of Fn is growing. Abnormal outbreak of Fn in biocenoses and over fields of phytoplankton can be associated with a well-known effect of «neutron trap» in heterogeneous environments, and the thermalization of the epithermal neutrons. Presence of the biological answer to weak streams thermal neutrons allow to assume, that these corpuscular streams are one of the "intermediaries" allowing alive organisms to feel a lot of astrogeophysical events, in addition to known climatic factors. In addition, the thermal neutron flux density is the integral characteristic,which allows to make a"neutron portrait " of the resort or the countryside. Thus, speaking about the anomalies of the natural radioactive background , special attention should be paid to the level Fn and its variations, and the potential impact on biological objects and human. The data obtained interaction of neutron flux and biological objects may be important for their adaptation to extreme environmental conditions. Our data suggest that even in the lower layers of troposphere value thermal neutron flux (Fn) can be quite high, confirm the need for further studies to human security at the high altitude and transcontinental air flights.

Plotnikova, Natalia

159

Geochemical and geophysical anomalies in the western part of the Sheep Creek Range, Lander County, Nevada  

USGS Publications Warehouse

Extensive geochemical anomalies are present along the west side of the Sheep Creek Range in Lander County, Nev. Anomalous concentrations of zinc, arsenic, mercury, silver, copper, lead, and to some extent gold, molybdenum, and antimony occur in iron-rich material along fracture planes and in quartz veins in Paleozoic formations. A magnetic anomaly occurs over a pediment at the southern part of the range, close to one of the geochemical anomalies. Gravity and electrical resistivity measurements suggest that the magnetic anomaly is caused by an intrusive igneous mass rather than by a block of downfaulted basalt. A limited amount of shallow drilling would clarify the geochemical and geophysical data.

Gott, Garland Bayard; Zablocki, Charles J.

1968-01-01

160

Major congenital anomalies in babies born with Down syndrome: A EUROCAT population-based registry study.  

PubMed

Previous studies have shown that over 40% of babies with Down syndrome have a major cardiac anomaly and are more likely to have other major congenital anomalies. Since 2000, many countries in Europe have introduced national antenatal screening programs for Down syndrome. This study aimed to determine if the introduction of these screening programs and the subsequent termination of prenatally detected pregnancies were associated with any decline in the prevalence of additional anomalies in babies born with Down syndrome. The study sample consisted of 7,044 live births and fetal deaths with Down syndrome registered in 28 European population-based congenital anomaly registries covering seven million births during 2000-2010. Overall, 43.6% (95% CI: 42.4-44.7%) of births with Down syndrome had a cardiac anomaly and 15.0% (14.2-15.8%) had a non-cardiac anomaly. Female babies with Down syndrome were significantly more likely to have a cardiac anomaly compared to male babies (47.6% compared with 40.4%, P?anomaly (12.9% compared with 16.7%, P?anomalies in babies with Down syndrome has remained constant, suggesting that population screening for Down syndrome and subsequent terminations has not influenced the prevalence of specific congenital anomalies in these babies. © 2014 Wiley Periodicals, Inc. PMID:25257471

Morris, Joan K; Garne, Ester; Wellesley, Diana; Addor, Marie-Claude; Arriola, Larraitz; Barisic, Ingeborg; Beres, Judit; Bianchi, Fabrizio; Budd, Judith; Dias, Carlos Matias; Gatt, Miriam; Klungsoyr, Kari; Khoshnood, Babak; Latos-Bielenska, Anna; Mullaney, Carmel; Nelen, Vera; Neville, Amanda J; O'Mahony, Mary; Queisser-Luft, Annette; Randrianaivo, Hanitra; Rankin, Judith; Rissmann, Anke; Rounding, Cath; Sipek, Antonin; Stoianova, Sylvia; Tucker, David; de Walle, Hermien; Yevtushok, Lyubov; Loane, Maria; Dolk, Helen

2014-12-01

161

An Analysis of the 1999 DARPA/Lincoln Laboratory Evaluation Data for Network Anomaly Detection  

E-print Network

in the evaluation of signature detectors. Scientific advances rely on reproducibility of results so that they canAn Analysis of the 1999 DARPA/Lincoln Laboratory Evaluation Data for Network Anomaly Detection TR investigate potential simulation artifacts and their effects on the evaluation of network anomaly detection

Somayaji, Anil

162

Winter-to-winter recurrence of sea surface temperature, salinity and mixed layer depth anomalies  

Microsoft Academic Search

The mean seasonal cycle of mixed layer depth (MLD) in the extratropical oceans has the potential to influence temperature, salinity and mixed layer depth anomalies from one winter to the next. Temperature and salinity anomalies that form at the surface and spread throughout the deep winter mixed layer are sequestered beneath the mixed layer when it shoals in spring, and

Michael A Alexander; Michael S Timlin; James D Scott

2001-01-01

163

Correlation of groundwater radon anomalies with earthquakes in the greater Palmdale bulge area  

SciTech Connect

Recent measurements in the Central Transverse Ranges of southern California suggest possible correlations of changes in groundwater radon content with occurences of nearby earthquakes. Since measurements began in 1974, three radon anomalies have been accompanied by subsequent nearby seismic events. Two of these anomalies were associated with moderate-sized earthquakes and one with a swarm. Within a 60-day window prior to the seismicity, groundwater radon increased in each case at sites close to the earthquake epicenters. Before the Big Bear earthquake of June 30, 1979 (M = 4.8), radon anomalies were found at three nearby monitoring sites. Groundwater radon content at one site near the January 1, 1979 Malibu earthquake (M = 5.0) showed negative as well as positive anomalies both prior to and following the earthquake. A radon anomaly occurred at a nearby spring prior to the fall 1976 Palmdale swarm. The observed pattern is similar to pre-earthquake anomalies reported from Russia, China, and Japan.

Teng, T.; Sun, L.; McRaney, J.K.

1981-05-01

164

Gravitational Anomaly and Hydrodynamics  

Microsoft Academic Search

We study the anomalous induced current of a vortex in a relativistic fluid via the chiral vortical effect, which is analogous to the anomalous current induced by a magnetic field via the chiral magnetic effect. We perform this analysis at weak and strong coupling. We discuss inequivalent implementations to the chemical potential for an anomalous symmetry. At strong coupling we

Karl Landsteiner; Eugenio Megías; Luis Melgar; Francisco Pena-Benitez

2012-01-01

165

Polar Wander of Mars: Evidence from Magnetic Anomalies  

Microsoft Academic Search

The pole positions determined from 16 magnetic anomalies indicate that the dipole core field axis was at 25 N. If the dipole core field coincided with the rotation axis of Mars at the time of magnetization the pole positions suggest that the axis of rotation of Mars has wandered by 65°.

J. Arkani-Hamed; D. Boutin

2003-01-01

166

Anomalies in an infant with Nager acrofacial dysostosis.  

PubMed

We report on an infant with Nager acrofacial dysostosis, laryngeal and epiglottic hypoplasia, abnormal septation of the right middle lobe of the lung, hypoplastic right first rib, and dislocation of the right hip. These findings suggest the possibility that patients with the Nager syndrome may have other developmental defects in addition to the facial and acral anomalies associated with this syndrome. PMID:4025401

Krauss, C M; Hassell, L A; Gang, D L

1985-08-01

167

Iridium Anomaly Approximately Synchronous with Terminal Eocene Extinctions  

Microsoft Academic Search

An iridium anomaly has been found in coincidence with the known microtektite level in cores from Deep Sea Drilling Project site 149 in the Caribbean Sea. The iridium was probably not in the microtektites but deposited simultaneously with them; this could occur if the iridium was deposited from a dust cloud resulting from a bolide impact, as suggested for the

Walter Alvarez; Frank Asaro; Helen V. Michel; Luis W. Alvarez

1982-01-01

168

Graph anomalies in cyber communications  

SciTech Connect

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.

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

169

Measuring anomaly with algorithmic entropy  

NASA Astrophysics Data System (ADS)

Anomaly detection refers to the identification of observations that are considered outside of normal. Since they are unknown to the system prior to training and rare, the anomaly detection problem is particularly challenging. Model based techniques require large quantities of existing data are to build the model. Statistically based techniques result in the use of statistical metrics or thresholds for determining whether a particular observation is anomalous. I propose a novel approach to anomaly detection using wavelet based algorithmic entropy that does not require modeling or large amounts of data. My method embodies the concept of information distance that rests on the fact that data encodes information. This distance is large when little information is shared, and small when there is greater information sharing. I compare my approach with several techniques in the literature using data obtained from testing of NASA's Space Shuttle Main Engines (SSME)

Solano, Wanda M.

170

Spacecraft environmental anomalies expert system  

NASA Technical Reports Server (NTRS)

A microcomputer-based expert system is being developed at the Aerospace Corporation Space Sciences Laboratory to assist in the diagnosis of satellite anomalies caused by the space environment. The expert system is designed to address anomalies caused by surface charging, bulk charging, single event effects and total radiation dose. These effects depend on the orbit of the satellite, the local environment (which is highly variable), the satellite exposure time and the hardness of the circuits and components of the satellite. The expert system is a rule-based system that uses the Texas Instruments Personal Consultant Plus expert system shell. The completed expert system knowledge base will include 150 to 200 rules, as well as a spacecraft attributes database, an historical spacecraft anomalies database, and a space environment database which is updated in near real-time. Currently, the expert system is undergoing development and testing within the Aerospace Corporation Space Sciences Laboratory.

Koons, H. C.; Gorney, D. J.

1988-01-01

171

Scalar Field Models: From the Pioneer Anomaly to Astrophysical Constraints  

E-print Network

In this work we study how scalar fields may affect solar observables, and use the constraint on the Sun's central temperature to extract bounds on the parameters of relevant models. Also, a scalar field driven by a suitable potential is shown to produce an anomalous acceleration similar to the one found in the Pioneer anomaly.

J. Paramos

2005-05-17

172

Boolean Search Suggestions in Primo  

E-print Network

Poster presented at Ex Libris Users of North America (ELUNA) 2014 Meeting in Montreal, Canada April 29 - May 2, 2014. Discusses the development and assessment of a JavaScript add-on to Primo that provides Boolean search suggestions based on search...

Hanrath, Scott

2014-05-01

173

Towards Social Semantic Suggestive Tagging  

Microsoft Academic Search

The organization of the knowledge on the web is increasingly becoming a social task performed by online communities whose members share a common interest in classifying different types of information for a later retrieval. Collaborative tagging systems allow people to organize a set of resources of interest through unconstrained annotations based on free keywords commonly named tags. Suggestive tagging techniques

Fabio Calefato; Domenico Gendarmi; Filippo Lanubile

2007-01-01

174

ARCHAEOLOGY Suggested Readings in Archaeology  

E-print Network

ARCHAEOLOGY Suggested Readings in Archaeology The following is a list of some of the major by those wishing more detailed information. Educators' Resources Archaeology in the Classroom. A Resource. Archaeological Institute of America. Archaeologists at Work: A Teacher's Guide to Classroom Archaeology. 2nd ed

Mathis, Wayne N.

175

Online Training Sessions: Suggested Guidelines.  

ERIC Educational Resources Information Center

These planning and evaluative guidelines for online trainers utilize a sliding scale--from minimal to suggested to optimal--for five types of training sessions: (1) Search Service--Beginning; (2) Search Service--Advanced; (3) Search Service--Subject; (4) Database Producer; and (5) Independent Introductory Workshop. (RAA)

Cabonell, Martha; And Others

1981-01-01

176

SUGGESTIONS FOR WEED CONTROL IN  

E-print Network

and mechanical weed control include: 1. Remove light or spotty infestations of weeds by hand hoeing or spot for continued infestation. 5. Consider the economics of using mechanical cultivation alone for weed controlB-5038 10-98 SUGGESTIONS FOR WEED CONTROL IN PASTURES AND FORAGES Texas Agricultural Extension

Mukhtar, Saqib

177

Prevent Cyberbullying: Suggestions for Parents  

ERIC Educational Resources Information Center

The school, playground, and neighborhood often come to mind when one thinks about bullying that occurs among children and teens. However, given the significant role technology plays in the lives of today's youth, the potential of these media to function as a venue for social interaction that includes victimization, or cyberbullying, also needs to…

Demaray, Michelle K.; Brown, Christina F.

2009-01-01

178

Modelling Mars' Magnetic Anomalies  

Microsoft Academic Search

An internal potential function was derived up to n=90 to improve upon an ongoing study of the crustal structure of the Martian magnetic field. The data included MGS magnetic observations below 200 km altitude taken during the two aerobraking phases (AB1 and AB2), the Science Phase Orbits (SPO), as well as higher altitude (370--440 km) data taken on the nightside

B. B. Ferguson; J. C. Cain; D. T. Mozzoni

2001-01-01

179

Ebstein's anomaly: the Broussais approach.  

PubMed

Ebstein's anomaly is rare, but it is the most frequent cause of congenital tricuspid valve anomaly. For many years valve replacement was performed. Conservative techniques are now preferred due to improvement of the results. The goals of surgery are to restore a normal tricuspid valve function, to preserve the right ventricular contractility and to decrease the risk of rhythm disturbances. Basically, the technique is based on mobilization of the anterior leaflet and longitudinal plication of the right ventricle. A bidirectional cavo pulmonary shunt is used in severe cases. Results are correlated with the severity of the disease, the expertise of the surgical team and also with the perioperative management. PMID:24415583

Chauvaud, Sylvain; Carpentier, Alain

2008-01-01

180

Analysis of DSN software anomalies  

NASA Technical Reports Server (NTRS)

A categorized data base of software errors which were discovered during the various stages of development and operational use of the Deep Space Network DSN/Mark 3 System was developed. A study team identified several existing error classification schemes (taxonomies), prepared a detailed annotated bibliography of the error taxonomy literature, and produced a new classification scheme which was tuned to the DSN anomaly reporting system and encapsulated the work of others. Based upon the DSN/RCI error taxonomy, error data on approximately 1000 reported DSN/Mark 3 anomalies were analyzed, interpreted and classified. Next, error data are summarized and histograms were produced highlighting key tendencies.

Galorath, D. D.; Hecht, H.; Hecht, M.; Reifer, D. J.

1981-01-01

181

Uncertainty in magnetization directions derived from planetary magnetic anomalies in view of numerical experiments with coalesced anomalies from Earth  

Microsoft Academic Search

Martian magnetization vectors and paleopole locations determined by different investigators using different methodologies are contradictory. I suggest that one of the reasons for this is that the anomalies that are assumed to be caused by a homogeneously magnetized source may actually be due to coalescence of multiple crustal sources that may be magnetically coherently or incoherently magnetized and whose coalescence

D. Ravat

2006-01-01

182

Neural Mechanisms of Rapid Sensitivity to Syntactic Anomaly  

PubMed Central

Recent psycholinguistic models hypothesize that anticipatory processing can speed the response to linguistic input during language comprehension by pre-activating representations necessary for word recognition. We investigated the neurocognitive mechanisms of anticipatory processing by recording event-related potentials (ERPs) to syntactically anomalous (The thief was caught by for police) and well-formed (e.g., The thief was caught by the police) sentences. One group of participants saw anomalies elicited by the same word in every instance (e.g., for; low-variability stimuli), providing high affordances for predictions about the word-form appearing in the critical position. A second group saw anomalies elicited by seven different prepositions (at, of, on, for, from, over, with; high-variability stimuli) across the study, creating a more difficult prediction task. Syntactic category anomalies enhanced the occipital-temporal N170 component of the ERP, indicating rapid sensitivity – within 200?ms of word-onset – to syntactic anomaly. For low-variability but not the high-variability stimuli, syntactic anomaly also enhanced the earlier occipital-temporal P1 component, around 130?ms after word-onset, indicating that affordances for prediction engendered earlier sensitivity to syntactic anomaly. Independent components analysis revealed three sources within the ERP signal whose functional dynamics were consistent with predictive processing and early responses to syntactic anomaly. Distributed neural source modeling (sLORETA) of these early active sources produced a candidate network for early responses to words during reading in the right posterior occipital, left occipital-temporal, and medial parietal cortex. PMID:23515395

Kim, Albert E.; Gilley, Phillip M.

2013-01-01

183

The North German Conductivity Anomaly revisited  

NASA Astrophysics Data System (ADS)

The North German Conductivity Anomaly was detected already in the early years of electromagnetic deep sounding. It refers to the reversal of induction arrows (as a graphical representation of the tipper transfer function, the ratio of vertical to horizontal magnetic field variations) at the northern and southern margins of the North German Basin. In spite of the many experiments carried out so far, its origin has remained ambiguous; explanations encompass a deep-crustal or even mantle source as well as the simple response to deepening of sedimentary sequences in the centre of the basin. Here, we report on modelling of new long-period magnetotelluric data collected along two profiles in NE Germany and S Sweden, with one transect crossing the Sorgenfrei-Tornquist Zone as the main boundary between Precambrian Baltica and the Palaeozoic belts of central Europe. With the exception of a few sites probably influenced by 3-D salt domes, the data allow a 2-D analysis. Resolution is reduced for large depths due to a well-conducting, saline aquifer, extending across the entire basin. The main result is that the reversal of induction arrows can largely be explained by the resistivity contrast between crystalline basement and sedimentary basin fill. Beneath Rügen island, a southward dipping conductor is interpreted to reflect an alum shale layer in Middle Cambrian-Lower Ordovician sediments. Beneath the southern basin, a moderately conductive upper mantle is modelled (although not very well resolved) which may reflect the thinning of the lithosphere as implied by seismic tomography. As the main anomalously inductive effect is primarily explained by the basin edges and numerous other anomalies exist inside the basin, we suggest not using the term 'North German Conductivity Anomaly' any longer.

Schäfer, A.; Houpt, L.; Brasse, H.; Hoffmann, N.

2011-10-01

184

On isotopic anomalies in samarium. [in Allende meteorite  

NASA Technical Reports Server (NTRS)

The solar isotopic composition of Sm is decomposed into s, r, and p components. The anomaly pattern discovered by Lugmair et al. (1978) in EK1-04 Allende inclusion can be presented as a fractionation of the average s-pattern from the average r-pattern. This representation requires a fractionation of 0.029%/(amu) and either (1) a 0.42% deficiency of s relative to r and a 0.15% deficiency of p relative to r, or (2) a 0.42% excess of r relative to s and a 0.27% excess of p relative to s. The nature of this anomaly suggest a systematic physical fractionation of r, s, and p nuclei from each other in the initial condition leading to EK1-04. A neighboring supernova injection would not be expected to produce this anomaly.

Clayton, D. D.

1979-01-01

185

Body Stalk Anomaly in a 9-Week Pregnancy  

PubMed Central

Body stalk anomaly is a rare and severe malformation syndrome in which the exact pathophysiology and trigger factors are still unknown. This is a case of a 30-year-old patient who underwent ultrasound at 9 weeks of gestation. It revealed an abnormal location of the inferior body of the embryo in the coelomic space. The findings suggested a short umbilical cord syndrome. In order to confirm the diagnosis, the patient was scheduled for a second ultrasonography at 11 weeks of gestation. The obtained images, confirmed the location of the inferior body in the coelomic space with no visible bladder, absence of the right leg, severe abdominal wall defect, consistent with an omphalocele, and a short 5?mm umbilical cord. These last ultrasonographic findings were consistent with body stalk anomaly. Because of severe malformation incompatible with life, the patient was offered termination of pregnancy. Pathologic examination confirmed the suspected pathology of body stalk anomaly. PMID:25105039

Quijano, Fabio E.; Rey, María Mónica; Echeverry, Mariana; Axt-Fliedner, Roland

2014-01-01

186

Isotopic anomalies and proton irradiation in the early solar system  

NASA Technical Reports Server (NTRS)

Nuclear cross sections relevant to the various isotopic-abundance anomalies found in solar-system objects are evaluated in an attempt to set constraints on the hypothesized mechanism of irradiation of forming planetesimals by energetic protons from the young sun. A power-law proton spectrum is adopted, attention is restricted to proton energies less than about 20 MeV, and average cross sections are calculated for several reactions that might be expected to lead to the observed anomalies. The following specific anomalies are examined in detail: Al-26, Na-22, Xe-126, I-129, Kr-80, V-50, Nb-92, La-138, Ta-180, Hg-196, K-40, Ar-36, O-17, O-18, N-15, C-13, Li, Be, and B. It is suggested that the picture of presolar-grain carriers accounts for the facts more naturally than do irradiation models.

Clayton, D. D.; Dwek, E.; Woosley, S. E.

1977-01-01

187

Iridium anomaly approximately synchronous with terminal eocene extinctions.  

PubMed

An iridium anomaly has been found in coincidence with the known microtektite level in cores from Deep Sea Drilling Project site 149 in the Caribbean Sea. The iridium was probably not in the microtektites but deposited simultaneously with them; this could occur if the iridium was deposited from a dust cloud resulting from a bolide impact, as suggested for the anomaly associated with the Cretaceous-Tertiary boundary. Other workers have deduced that the microtektites are part of the North American strewn tektite field, which is dated at about 34 million years before present, and that the microtektite horizon in deep-sea cores is synchronous with the extinction of five radiolarian species. Mass extinctions also occur in terrestrial mammals within 4 million years of this time. The iridium anomaly and the tektites and microtektites are supportive of a major bolide impact about 34 million years ago. PMID:17819180

Alvarez, W; Asaro, F; Michel, H V; Alvarez, L W

1982-05-21

188

Iridium anomaly approximately synchronous with terminal eocene extinctions  

SciTech Connect

An iridium anomaly has been found in coincidence with the known microtektite level in cores from Deep Sea Drilling Project site 149 in the Caribbean Sea. The iridium was probably not in the microtektites but deposited simultaneously with them; this could occur if the iridium was deposited from a dust cloud resulting from a bolide impact, as suggested for the anomaly associated with the Cretaceous-Tertiary boundary. Other workers have deduced that the microtektites are part of the North American strewn tektite field, which is dated at about 34 million years before present, and that the microtektite horizon in deep-sea cores is synchronous with the extinction of five radiolarian species. Mass extinctions also occur in terrestrial mammals within 4 million years of this time. The iridium anomaly and the tektites and microtektites are supportive of a major bolide impact about 34 million years ago.

Alvarez, W. (Univ. of California, Berkeley); Asaro, F.; Michel, H.V.; Alvarez, L.W.

1982-05-21

189

Attention focusing and anomaly detection in systems monitoring  

NASA Technical Reports Server (NTRS)

Any attempt to introduce automation into the monitoring of complex physical systems must start from a robust anomaly detection capability. This task is far from straightforward, for a single definition of what constitutes an anomaly is difficult to come by. In addition, to make the monitoring process efficient, and to avoid the potential for information overload on human operators, attention focusing must also be addressed. When an anomaly occurs, more often than not several sensors are affected, and the partially redundant information they provide can be confusing, particularly in a crisis situation where a response is needed quickly. The focus of this paper is a new technique for attention focusing. The technique involves reasoning about the distance between two frequency distributions, and is used to detect both anomalous system parameters and 'broken' causal dependencies. These two forms of information together isolate the locus of anomalous behavior in the system being monitored.

Doyle, Richard J.

1994-01-01

190

Numerical anomalies mimicking physical effects  

SciTech Connect

Numerical simulations of flows with shock waves typically use finite-difference shock-capturing algorithms. These algorithms give a shock a numerical width in order to generate the entropy increase that must occur across a shock wave. For algorithms in conservation form, steady-state shock waves are insensitive to the numerical dissipation because of the Hugoniot jump conditions. However, localized numerical errors occur when shock waves interact. Examples are the ``excess wall heating`` in the Noh problem (shock reflected from rigid wall), errors when a shock impacts a material interface or an abrupt change in mesh spacing, and the start-up error from initializing a shock as a discontinuity. This class of anomalies can be explained by the entropy generation that occurs in the transient flow when a shock profile is formed or changed. The entropy error is localized spatially but under mesh refinement does not decrease in magnitude. Similar effects have been observed in shock tube experiments with partly dispersed shock waves. In this case, the shock has a physical width due to a relaxation process. An entropy anomaly from a transient shock interaction is inherent in the structure of the conservation equations for fluid flow. The anomaly can be expected to occur whenever heat conduction can be neglected and a shock wave has a non-zero width, whether the width is physical or numerical. Thus, the numerical anomaly from an artificial shock width mimics a real physical effect.

Menikoff, R.

1995-09-01

191

Gravitational Anomaly and Transport Phenomena  

Microsoft Academic Search

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

Karl Landsteiner; Eugenio Megías; Francisco Pena-Benitez

2011-01-01

192

Archaeological Anomalies in the Bahamas  

Microsoft Academic Search

Controversial claims have been made for the presence of anom- alous underwater archaeological sites in the Bahamas by a number of in- vestigators. The proponents emphasize extraordinary explanations for the anomalies and tend to bypass the scientific journals in favor of popular presentations with little scientific rigor. The skeptics debunk selected claims for some of the sites, do not adequately

DOUGLAS G. RICHARDS

1988-01-01

193

Development anomalies of the occiput  

Microsoft Academic Search

Four patients with classical features of bathrocephalism are described. Three further patients with developmental anomalies of the occiput are described and these are contrasted with those having classical bathrocephalism. The distinction between the two groups is emphasised. Reference is made to cases described in the pediatric literature which appears at times to depart from the traditional norms and classical notation.

J. Wickenhauser; O. Hochberg

1974-01-01

194

Suggestions for Popularizing Civil Aviation  

NASA Technical Reports Server (NTRS)

The public generally is taking very little interest in the progress of Civil Aviation, and the time has come to educate the public in aeronautics and to make them realize the far-reaching importance of air transport. Briefly, the whole problem resolves itself into discovering and applying means for bringing some of the many aspects and effects of civil aviation into the everyday lives of the public. The report suggests three principal groups of methods: (1) Bring aviation into daily contact with the public. (2) Bring the public into daily contact with aviation. (3) General publicity.

1926-01-01

195

Automatic Construction of Anomaly Detectors from Graphical Models  

SciTech Connect

Detection of rare or previously unseen attacks in cyber security presents a central challenge: how does one search for a sufficiently wide variety of types of anomalies and yet allow the process to scale to increasingly complex data? In particular, creating each anomaly detector manually and training each one separately presents untenable strains on both human and computer resources. In this paper we propose a systematic method for constructing a potentially very large number of complementary anomaly detectors from a single probabilistic model of the data. Only one model needs to be trained, but numerous detectors can then be implemented. This approach promises to scale better than manual methods to the complex heterogeneity of real-life data. As an example, we develop a Latent Dirichlet Allocation probability model of TCP connections entering Oak Ridge National Laboratory. We show that several detectors can be automatically constructed from the model and will provide anomaly detection at flow, sub-flow, and host (both server and client) levels. This demonstrates how the fundamental connection between anomaly detection and probabilistic modeling can be exploited to develop more robust operational solutions.

Ferragut, Erik M [ORNL; Darmon, David M [ORNL; Shue, Craig A [ORNL; Kelley, Stephen [ORNL

2011-01-01

196

Gravitational Anomaly and Hydrodynamics  

E-print Network

We study the anomalous induced current of a vortex in a relativistic fluid via the chiral vortical effect, which is analogous to the anomalous current induced by a magnetic field via the chiral magnetic effect. We perform this analysis at weak and strong coupling. We discuss inequivalent implementations to the chemical potential for an anomalous symmetry. At strong coupling we use a holographic model with a pure gauge and mixed gauge-gravitational Chern-Simons term in the action. We discuss the holographic renormalization and show that the Chern-Simons terms do not induce new divergences. Strong and weak coupling results agree precisely. We also point out that the holographic calculation can be done without a singular gauge field configuration on the horizon of the black hole.

Landsteiner, Karl; Melgar, Luis; Pena-Benitez, Francisco

2011-01-01

197

Gravitational Anomaly and Hydrodynamics  

E-print Network

We study the anomalous induced current of a vortex in a relativistic fluid via the chiral vortical effect, which is analogous to the anomalous current induced by a magnetic field via the chiral magnetic effect. We perform this analysis at weak and strong coupling. We discuss inequivalent implementations to the chemical potential for an anomalous symmetry. At strong coupling we use a holographic model with a pure gauge and mixed gauge-gravitational Chern-Simons term in the action. We discuss the holographic renormalization and show that the Chern-Simons terms do not induce new divergences. Strong and weak coupling results agree precisely. We also point out that the holographic calculation can be done without a singular gauge field configuration on the horizon of the black hole.

Karl Landsteiner; Eugenio Megias; Luis Melgar; Francisco Pena-Benitez

2011-11-11

198

Gravity tests in the solar system and the Pioneer anomaly  

E-print Network

We build up a new phenomenological framework associated with a minimal generalization of Einsteinian gravitation theory. When linearity, stationarity and isotropy are assumed, tests in the solar system are characterized by two potentials which generalize respectively the Newton potential and the parameter $\\gamma $ of parametrized post-Newtonian formalism. The new framework seems to have the capability to account for the Pioneer anomaly besides other gravity tests.

Marc-Thierry Jaekel; Serge Reynaud

2005-04-05

199

Characterization of NPP Visible/Infrared Imager Radiometer Suite (VIIRS) Reflective Solar Bands Dual Gain Anomaly  

NASA Technical Reports Server (NTRS)

The Visible/Infrared Imager Radiometer Suite (VIIRS) contains six dual gain bands in the reflective solar spectrum. The dual gain bands are designed to switch gain mode at pre-defined thresholds to achieve high resolution at low radiances while maintaining the required dynamic range for science. During pre-launch testing, an anomaly in the electronic response before transitioning from high to low gain was discovered and characterized. On-orbit, the anomaly was confirmed using MODIS data collected during Simultaneous Nadir Overpasses (SNOs). The analysis of the Earth scene data shows that dual gain anomaly can be determined at the orbital basis. To characterize the dual gain anomaly, the anomaly region and electronic offsets were tracked per week during the first 8 month of VIIRS operation. The temporal analysis shows the anomaly region can drift 20 DN and is impacted by detectors DC Restore. The estimated anomaly flagging regions cover 2.5 % of the high gain dynamic range and are consistent with prelaunch and on-orbit LUT. The prelaunch results had a smaller anomaly range (30-50 DN) and are likely the results of more stable electronics from the shorter data collection time. Finally, this study suggests future calibration efforts to focus on the anomaly's impact on science products and possible correction method to reduce uncertainties.

Lee, Shihyan; McIntire, Jeff; Oudari, Hassan

2012-01-01

200

Neurofibromas with imaging characteristics resembling vascular anomalies.  

PubMed

OBJECTIVE. Although neurofibromas are rare, their initial clinical and imaging presentation can mimic those of vascular anomalies, particularly if the characteristic clinical features of neurofibromatosis are not present. The diagnostic challenges encountered in five cases of histologically proven neurofibromas, initially diagnosed as vascular anomalies, are reviewed and discussed. CONCLUSION. The clinical and imaging differences between neurofibromas and vascular anomalies are detailed with the histopathologic features to better understand why some neurofibromas are diagnosed as vascular anomalies. PMID:25415736

Yilmaz, Sabri; Ozolek, John A; Zammerilla, Lauren L; Fitz, Charles R; Grunwaldt, Lorelei J; Crowley, John J

2014-12-01

201

Revisiting Calendar Anomalies in Asian Stock Markets Using a Stochastic Dominance Approach  

E-print Network

Revisiting Calendar Anomalies in Asian Stock Markets Using a Stochastic Dominance Approach Hooi Abstract Extensive evidence on the prevalence of calendar effects suggests that there exist abnormal returns. Some recent studies, however, have concluded that calendar effects have largely disappeared

Chaudhuri, Sanjay

202

Polar Spin Axis Anomaly  

NASA Technical Reports Server (NTRS)

The Global Geospace Science (GGS) Polar Plasma Laboratory (POLAR) spacecraft was launched on February 24, 1996, by a Delta 2. The spacecraft, a major axis spinner, appeared to function nominally throughout the early mission phase, which included several deployments, and orbit and attitude maneuvers. Of particular interest is the fact that the spacecraft was launched with a deliberate dynamic imbalance. During a segment of early orbit operations, a pair of Lanyard Deployed Booms (LDB) were extended. These booms were not identical; the intent was that the spacecraft would be nearly dynamically balanced after they were deployed. The spacecraft contained two dynamic balance mechanisms intended to fine tune the balance on orbit. However, subsequent images taken by the science instruments on the Despun Platform during the dynamic balancing segment indicated an offset of the principal spin axis from the geometric axis. This offset produced a sinusoidal blurring of the science images sufficiently large to degrade science data below mission requirement specifications. In the end, the imbalance encountered in flight was significantly outside the correction capability of the balances. The purpose of this paper is to examine the flight data during the various deployment and maneuver stages of the early orbit operations coupled with analytical simulations to discuss some of the potential causes of the resultant imbalance.

Crouse, Patrick L.; Flatley, Thomas W.; Morgenstern, Wendy M.

1997-01-01

203

Limb Body Wall Complex: A Rare Anomaly  

PubMed Central

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. PMID:24014975

Chikkannaiah, Panduranga; Dhumale, Hema; Kangle, Ranjit; Shekar, Rosini

2013-01-01

204

Features Suggestive of Gallbladder Malignancy  

PubMed Central

Objectives Gallbladder cancer carries an extremely high mortality rate, with a 5-year survival rate as low as 12%. Survival is dependent on the diagnosis of these tumors in their earliest stages. This study sought to describe the clinical and imaging features of stages T1, T2, and T3 gallbladder tumors and to illustrate features that may allow radiologists to make an early diagnosis. Materials and Methods After approval from the institutional review board, a search of the pathology department database yielded 18 patients with surgically proven T1, T2, and T3 gallbladder cancers with available preoperative computed tomography (CT) or magnetic resonance imaging. The imaging was reviewed for lesional morphology (focal polyploid mass, focal wall thickening, circumferential wall thickening), enhancement characteristics, liver invasion, locoregional lymph-adenopathy, and distant metastatic disease. The electronic medical record was also searched for demographic information and clinical presentation. Results There were 10 women and 8 men with a mean age of 69 years. Virtually all patients were symptomatic, with most patients demonstrating symptoms suggestive of underlying malignancy (including jaundice, weight loss, and chronic abdominal pain). Tumors on CT and MRI included 6 polyploid masses, 9 tumors with focal wall thickening, and 3 with circumferential wall thickening. The mean attenuation of those tumors imaged with CT was 59.4 Hounsfield units (HUs) on the arterial phase and 86.5 HUs on the venous phase, with a mean increase in Hounsfield attenuation between the arterial and venous phases of 28.2 HUs. Twelve of the 18 patients were correctly diagnosed prospectively on CT. Conclusions The imaging findings of gallbladder cancer can be subtle, regardless of whether the tumor presents as a discrete mass, focal wall thickening, or circumferential diffuse wall thickening, and radio-logists should be aware of the wide range of different possible appearances. Moreover, the vast majority of these patients had clinical symptoms suggestive of an underlying malignancy, and this should precipitate a careful evaluation of the gallbladder in all such cases. PMID:24625606

Mitchell, Charles H.; Johnson, Pamela T.; Fishman, Elliot K.; Hruban, Ralph H.; Raman, Siva P.

2015-01-01

205

Pioneer anomaly: What can we learn from LISA?  

E-print Network

The Doppler tracking data from two deep-space spacecraft, Pioneer 10 and 11, show an anomalous blueshift, which has been dubbed the "Pioneer anomaly". The effect is most commonly interpreted as a real deceleration of the spacecraft - an interpretation that faces serious challenges from planetary ephemerides. The Pioneer anomaly could as well indicate an unknown effect on the radio signal itself. Several authors have made suggestions how such a blueshift could be related to cosmology. We consider this interpretation of the Pioneer anomaly and study the impact of an anomalous blueshift on the Laser Interferometer Space Antenna (LISA), a planned joint ESA-NASA mission aiming at the detection of gravitational waves. The relative frequency shift (proportional to the light travel time) for the LISA arm length is estimated to 10E-16, which is much bigger than the expected amplitude of gravitational waves. The anomalous blueshift enters the LISA signal in two ways, as a small term folded with the gravitational wave signal, and as larger term at low frequencies. A detail analysis shows that both contributions remain undetectable and do not impair the gravitational-wave detection. This suggests that the Pioneer anomaly will have to be tested in the outer Solar system regardless if the effect is caused by an anomalous blueshift or by a real force.

Denis Defrere; Andreas Rathke

2005-09-07

206

Magsat scalar anomaly distribution - The global perspective  

NASA Technical Reports Server (NTRS)

It is established that geographic coincidences exist between high-altitude Magsat scalar anomalies and major geologic and tectonic structures, with oceanic abyssal plains overlain by negative anomalies agreeing well in spatial extent and position and submarine platforms lying beneath positive scalar anomalies. In addition, geographic coincidence is found in the continents between many high-latitude positive anomalies and shields and cratons in North America, Eurasia and Australia. While these correlations are qualitative, they serve to identify regions for detailed study. The global distribution of anomalies provides a basis for comparative study which will be enhanced when reduced-to-pole versions of the Magsat data become available.

Frey, H.

1982-01-01

207

Monoamniotic twins discordant for body stalk anomaly.  

PubMed

Abstract Body stalk anomaly is a rare malformation. This anomaly in monozygotic twins is extremely unusual. We describe a case of monoamniotic pregnancy discordant for body stalk anomaly diagnosed at 11 weeks. Ultrasound showed a fetus with a large anterior abdominal wall defect, anomaly of the spine and no evidence of lower extremities and other with a normal morphology. As far as our concern, only three monoamniotic pregnancies discordant for this malformation were reported. Our case represents the fourth reported monoamniotic pregnancy discordant for body stalk anomaly with diagnosis made by ultrasound and the second diagnosed in the first trimester. PMID:24588260

Tavares, Mariana Vide; Domingues, Ana Patrícia; Tavares, Margarida; Fonseca, Etelvina; Moura, Paulo

2015-01-01

208

Echocardiographic Assessment of Ebstein's Anomaly.  

PubMed

Ebstein's anomaly is a complex congenital lesion which primarily involves the tricuspid valve. The tricuspid leaflets are tethered to varying degrees to the right ventricular free wall and the ventricular septum often resulting in significant tricuspid regurgitation and a small functioning right ventricular chamber. Although the septal leaflet originates normally at the right atrioventricular junction, the proximal portion is often completely tethered to the ventricular septum resulting in a misconception and erroneous statements in many publications that its attachment is apically displaced. Although two-dimensional echocardiography represents the primary modality for the diagnosis of this anomaly, three-dimensional echocardiography provides incremental value in characterizing the extent and severity of tethering of individual tricuspid valve leaflets. This information is useful in surgical decision making whether to repair or replace the tricuspid valve. PMID:24888693

Booker, Oscar J; Nanda, Navin C

2015-01-01

209

Anomaly Mediation and Dimensional Transmutation  

E-print Network

We show how a sparticle spectrum characteristic of anomaly mediation can arise from a theory whose Lagrangian contains no explicit mass scale. The scale of supersymmetry breaking is governed by the gravitino mass, which is the vacuum expectation value of the F-term of the conformal compensator field, and the tachyonic slepton problem is resolved by the breaking of a U(1) gauge symmetry at a scale determined by dimensional transmutation.

D. R. T. Jones; G. G. Ross

2006-09-20

210

Anomalies and Discrete Chiral Symmetries  

SciTech Connect

The quantum anomaly that breaks the U(1) axial symmetry of massless multi-flavored QCD leaves behind a discrete flavor-singlet chiral invariance. With massive quarks, this residual symmetry has a close connection with the strong CP-violating parameter theta. One result is that if the lightest quarks are degenerate, then a first order transition will occur when theta passes through pi. The resulting framework helps clarify when the rooting prescription for extrapolating in the number of flavors is valid.

Creutz, M.

2009-09-07

211

Hemispheric asymmetry of surface temperature anomalies  

NASA Astrophysics Data System (ADS)

In recent months there has been some controversy concerning the possible effect of suspended sulfate aerosols on warming trends predicted to occur in response to steadily increasing greenhouse gas concentrations in the troposphere. Evidence in the recent literature both supporting and doubting the theory that aerosols have suppressed warming in the Northern Hemisphere more than in the Southern Hemisphere has relied on analyses of radiosonde observations covering various periods between 1958 and 1995. In this letter the UK Met Office/University of East Anglia Climatic Research Unit (Parker/Jones) data sets of mean surface temperature anomalies over land and sea for the past 140 years serve as an independent data base to test earlier reported results obtained from radiosonde observations. The results suggest that there is no evidence of any systematic differences in temperature trends between the two hemispheres.

Gordon, Adrian H.; Bye, John A. T.

1997-11-01

212

The mineralogy of global magnetic anomalies  

NASA Technical Reports Server (NTRS)

Progress is reported in developing predictive abilities to evaluate the potential stabilities of magnetic minerals in the Earth crust and mantle by: (1) computing oxidation state profiling as a function of temperature and pressure; (2) compiling data on basalts to establish validity of the oxidation state profiles; (3) determining Fe-Ni alloys in association with magnetitie as a function of temperature and oxidation state; and (4) acquiring large chemical data banks on the mineral ilmenite which decomposes to mineral spinel in the presence of high sulfur or carbonate environments in the lower crust upper mantle. In addition to acquiring these data which are related to constraining Curie isotherm depths, an excellent correlation was found between MAGSAT anomaly data and the geology of West Africa.

Haggerty, S. E. (principal investigator)

1981-01-01

213

6d, Coulomb branch anomaly matching  

NASA Astrophysics Data System (ADS)

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 ? 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.

Intriligator, Kenneth

2014-10-01

214

Satellite GN and C Anomaly Trends  

NASA Technical Reports Server (NTRS)

On-orbit anomaly records for satellites launched from 1990 through 2001 are reviewed to determine recent trends of un-manned space mission critical failures. Anomalies categorized by subsystems show that Guidance, Navigation and Control (GN&C) subsystems have a high number of anomalies that result in a mission critical failure when compared to other subsystems. A mission critical failure is defined as a premature loss of a satellite or loss of its ability to perform its primary mission during its design life. The majority of anomalies are shown to occur early in the mission, usually within one year from launch. GN&C anomalies are categorized by cause and equipment type involved. A statistical analysis of the data is presented for all anomalies compared with the GN&C anomalies for various mission types, orbits and time periods. Conclusions and recommendations are presented for improving mission success and reliability.

Robertson, Brent; Stoneking, Eric

2003-01-01

215

Columbus Payloads Flow Rate Anomalies  

NASA Technical Reports Server (NTRS)

The Columbus Active Thermal Control System (ATCS) is the main thermal bus for the pressurized racks working inside the European laboratory. One of the ATCS goals is to provide proper water flow rate to each payload (P/L) by controlling actively the pressure drop across the common plenum distribution piping. Overall flow measurement performed by the Water Pump Assembly (WPA) is the only flow rate monitor available at system level and is not part of the feedback control system. At rack activation the flow rate provided by the system is derived on ground by computing the WPA flow increase. With this approach, several anomalies were raised during these 3 years on-orbit, with the indication of low flow rate conditions on the European racks FSL, BioLab, EDR and EPM. This paper reviews the system and P/Ls calibration approach, the anomalies occurred, the engineering evaluation on the measurement approach and the accuracy improvements proposed, the on-orbit test under evaluation with NASA and finally discusses possible short and long term solutions in case of anomaly confirmation.

Quaranta, Albino; Bufano, Gaetana; DePalo, Savino; Holt, James M.; Szigetvari, Zoltan; Palumberi, Sergio; Hinderer, S.

2011-01-01

216

Limb anomalies in chromosomal aberrations.  

PubMed

This survey shows that there are at least 6 autosomal and 2 gonosomal aberrations which may produce specific types of limb anomaly in 30%-80% of cases. The "expressivity" of these anomalies covers a wide range within the morphogenetic pattern. No entirely specific malformation type is seen. The most unusual malformation, aplasia of the thumbs with proximal synostosis of the 4th aand 5th metacarpals, is seen in 13q- (13r) but the precise cytogenetic basis is not clear. Aplasia of the thumb associated with synostosis of the 4th and 5th metacarpals was occasionally described before (unilateral [105], bilateral [106] while synostosis only (V or Y shaped) may be due to a dominant [107] or an X-linked recessive gene [108]. Reduction malformations limited to radial heminelia have been noted in 4q- (4r) and in trisomy 18. Although the number of cases is still small the pattern is similar to that of thalidomide embryopathy, radial hemimelia (AD, 17910), cardiodigital syndromes (AD, 14290), and even Fanconi panmyelopathy (AR, 22790). It ranges from hypoplasia of the thenar muscles and thumb to pseudophocomelia which should be clearly distinguished from phocomelia because of the absence of the thumb and frequently of the 2nd and 3rd fingers. Nothing has to be added to the teratologic series published by Müller [58] and, more recently, Willert and Henkel [109], but the distribution of the various manifestations may diverge. Asymmetry in 4q- (4r) is noteworthy. Postaxial polydactyly which is noted in trisomy 13 and trisomy of the terminal portions of the long arm of No. 13 is as variable in distribution and morphology as is observed in families in which the gene (AD, 17420) is transmitted. The question cannot yet be answered whether infrequent anomalies of the limbs which do not fit into the morphologic pattern of these types, eg postaxial polydactyly in + 18 or absence of the radius in + 13 are random. Syndactyly of the 3rd and 4th but also of other digits is a frequent but variable anomaly in triploidy. It is very similar to hereditary zygodactyly (AD, 18590). Peripheral hypoplasia of several digits accompanied by onychodysplasia seems to be a frequent anomaly in 9p+ syndrome. It is similar to that seen in a syndrome with mental deficiency, peculiar facies, and stunted growth [110] in which no chromosomal aberration has been found up to the present. Dysostoses have been frequently noted in gonosomal aberations. Brachymetopodia in XO females maybe confused with pseudo-pseudohypoparathyroidism (XR, 30080) or brachydactyly type E (AD, 11330) when only the lateral metacarpals and/or metatarsals are shortened. However, further studies are needed in order to delineate these syndromes on the basis of different frequencies and radiologic patterns. The radioulnar synostosis noted in cases with supernumerary X chromosomes cannot be distinguished from the inherited anomaly (AD, 17930), but associated anomalies of the hand are uncommon. PMID:322750

Pfeiffer, R A; Santelmann, R

1977-01-01

217

Contributions of cretaceus quiet zone natural remanent magnetization to Magsat anomalies in the Southwest Indian Ocean  

NASA Technical Reports Server (NTRS)

The Magsat magnetic anomalies over the Southwest Indian Ocean are modeled using a combination of induced plus viscous remanent magnetization (IM/VRM) and natural remanent magnetization (NRM). Two broad, roughly parallel, SW to NE trending triple-peaked positive anomalies dominate the region, one lying south of Africa and the other north of Antarctica. Although these anomaly peaks generally correspond with the Agulhas Plateau/Maud Rise, Mozambique Plateau/Astrid Ridge, and Madagascar Ridge/Conrad Rise conjugate pairs, the IM/VRM contribution from structural characteristics (i.e., crustal thickness) accounts for only about 20% of the anomaly amplitudes. A spatially variable but observationally constrained NRM contribution in Cretaceous Quiet Zone (KQZ) crust is required to account for the location, shape, and amplitude contrast of these anomalies. Many crustal features in the Southwest Indian Ocean near Antarctica have little geophysical data to constrain their structure but do hagve tectonic conjugates near Africa for which much more geophysical data are generally available. Using geophysical and geological constraints from one member to model the magnetization structure of its conjugate reproduces the observed Magsat reduced-to-pole anomalies over both structures very well. This suggests that no significant alteration in their magnetization structure has occurred since the features split. Models of these conjugate structures show that IM/VRM reproduces the Magsat anomalies associated with non-KQZ crust but that both IM/VRM and a dominant NRM component are required to explain the anomalies associated with KQZ crust.

Fullerton, Lawrence G.; Frey, Herbert V.; Roark, James H.; Thomas, Herman H.

1994-01-01

218

Space Weather, Cosmic Rays, and Satellite Anomalies  

NASA Astrophysics Data System (ADS)

Results are presented of the Satellite Anomaly Project, which aims to improve the methods of safeguarding satellites in the Earth’s magnetosphere from the negative effects of the space environment. Anomaly data from the USSR and Russian “Kosmos” series satellites in the period 1971-1999 are combined into one database, together with similar information on other spacecraft. This database contains, beyond the anomaly information, various characteristics of space weather: geomagnetic activity indices (Ap, AE and Dst), fluxes and fluencies of electrons and protons at different energies, high energy cosmic ray variations and other solar, interplanetary and solar wind data. A comparative analysis of the distribution of each of these parameters relative to satellite anomalies was carried out for the total number of anomalies (about 6000 events), and separately for high altitude orbit satellites ( 5000 events) and low altitude (about 800 events). No relation was found between low and high altitude satellite anomalies. Daily numbers of satellite anomalies, averaged by a superposed epoch method around sudden storm commencements and proton event onsets for high (>1500 km) and low (<1500 km) altitude orbits revealed a big difference in behavior. Satellites were divided into several groups according to their orbital characteristics (altitude and inclination). The relation of satellite anomalies to the environmental parameters was found to be different for various orbits, and this should be taken into account when developing anomaly frequency models. The preliminary anomaly frequency models are presented.

Lev, Dorman

219

Scalar Potential Model of light  

NASA Astrophysics Data System (ADS)

Some observations of light are inconsistent with a wave--like model. Other observations of light are inconsistent with a particle--like model. A model of light is proposed wherein Newton's and Democritus's speculations are combined with the cosmological scalar potential model (SPM). The SPM was tested by confrontation with observations of galaxy HI rotation curves (RCs), asymmetric RCs, redshift, discrete redshift, galaxy central mass, and central velocity dispersion; and with observations of the Pioneer Anomaly. The resulting model of light will be tested by numerical simulation of a photon behaving in a wave-like manner such as diffusion, interference, reflection, spectrography, and the Afshar experiment. Although the SPM light model requires more work, early results are beginning to emerge that suggest possible tests because a few predictions are inconsistent with both the current particle and wave models of light and that suggest a re-interpretation of the equations of quantum mechanics.

Hodge, John

2008-04-01

220

ENSO Variability at Vanuatu during the Medieval Climate Anomaly  

NASA Astrophysics Data System (ADS)

The Medieval Climate Anomaly (MCA; ~1050 - 1250 CE) is a period of warm temperatures in the Northern Hemisphere high latitudes caused by enhanced solar forcing. The tropical response to this forcing is variable; sediment records from the tropical Pacific indicate warm conditions in the western tropics and cooler temperatures in the east during this interval, paired with precipitation changes that suggest a northward migration of the Intertropical Convergence Zone. Speleothem records and western Pacific sediment cores match this migration with a strengthened Asian monsoon, indicating a substantial reorganization in hydrology. However, the effect of these changes in zonal and meridional circulation patterns on the El Niño-Southern Oscillation (ENSO), the dominant mode of global interannual climate variability, is unclear. Conflicting hypotheses arise due to datasets that are too short to be representative of multidecadal ENSO variability trends, cannot identify individual ENSO events due to lower than annual resolution, or are located in remote, teleconnected regions. We present a suite of monthly resolved geochemical records from fossil Porites corals at Vanuatu (Tasmaloum, Espiritu Santo), a location whose climate is strongly influenced by variations in ENSO and the South Pacific Convergence Zone (SPCZ). Our proxy coral records of sea surface temperature (SST) and sea surface salinity (SSS) variations provide multidecadal- to centennial-scale windows into ENSO variability and mean climate state from ~600 - 1250 CE in the deep tropics. Preliminary results, based on coral Sr/Ca variations during a portion of the MCA, suggest that SST was cooler than modern at Vanuatu, with similar levels of total variability. Additional data acquisition and future work will focus on assessing potential ENSO event frequency and magnitude changes during the MCA in the deep tropics.

Hereid, K. A.; Quinn, T. M.; Taylor, F. W.; Edwards, R.; Cheng, H.; Shen, C.

2011-12-01

221

Modeled Northern Hemisphere Winter Climate Response to Realistic Siberian Snow Anomalies.  

NASA Astrophysics Data System (ADS)

Wintertime Northern Hemisphere climate variability is investigated using large-ensemble (20) numerical GCM simulations. Control simulations with climatological surface (land and ocean) conditions indicate that the Arctic Oscillation (AO) is an internal mode of the Northern Hemisphere atmosphere, and that it can be triggered through a myriad of perturbations. In this study the role of autumn land surface snow conditions is investigated. Satellite observations of historical autumn winter snow cover are applied over Siberia as model boundary conditions for two snow-forced experiments, one using the highest observed autumn snow cover extent over Siberia (1976) and another using the lowest extent (1988). The ensemble-mean difference between the two snow-forced experiments is computed to evaluate the climatic response to Siberian snow conditions. Experiment results suggest that Siberian snow conditions exert a modulating influence on the predominant wintertime Northern Hemisphere (AO) mode. Furthermore, an atmospheric teleconnection pathway is identified, involving well-known wave mean flow interaction processes throughout the troposphere and stratosphere. Anomalously high Siberian snow increases local upward stationary wave flux activity, weakens the stratospheric polar vortex, and causes upper-troposphere stationary waves to refract poleward. These related stationary wave and mean flow anomalies propagate down through the troposphere via a positive feedback, which results in a downward-propagating negative AO anomaly during the winter season from the stratosphere to the surface. This pathway provides a physical explanation for how regional land surface snow anomalies can influence winter climate on a hemispheric scale. The results of this study may potentially lead to improved predictions of the winter AO mode, based on Siberian snow conditions during the preceding autumn.

Gong, Gavin; Entekhabi, Dara; Cohen, Judah

2003-12-01

222

Enzyme leaching of surficial geochemical samples for detecting hydromorphic trace-element anomalies associated with precious-metal mineralized bedrock buried beneath glacial overburden in northern Minnesota  

USGS Publications Warehouse

One objective of the International Falls and Roseau, Minnesota, CUSMAP projects was to develop a means of conducting regional-scale geochemical surveys in areas where bedrock is buried beneath complex glacially derived overburden. Partial analysis of B-horizon soils offered hope for detecting subtle hydromorphic trace-element dispersion patterns. An enzyme-based partial leach selectively removes metals from oxide coatings on the surfaces of soil materials without attacking their matrix. Most trace-element concentrations in the resulting solutions are in the part-per-trillion to low part-per-billion range, necessitating determinations by inductively coupled plasma/mass spectrometry. The resulting data show greater contrasts for many trace elements than with other techniques tested. Spatially, many trace metal anomalies are locally discontinuous, but anomalous trends within larger areas are apparent. In many instances, the source for an anomaly seems to be either basal till or bedrock. Ground water flow is probably the most important mechanism for transporting metals toward the surface, although ionic diffusion, electrochemical gradients, and capillary action may play a role in anomaly dispersal. Sample sites near the Rainy Lake-Seine River fault zone, a regional shear zone, often have anomalous concentrations of a variety of metals, commonly including Zn and/or one or more metals which substitute for Zn in sphalerite (Cd, Ge, Ga, and Sn). Shifts in background concentrations of Bi, Sb, and As show a trend across the area indicating a possible regional zoning of lode-Au mineralization. Soil anomalies of Ag, Co, and Tl parallel basement structures, suggesting areas that may have potential for Cobalt/Thunder Baytype silver viens. An area around Baudette, Minnesota, which is underlain by quartz-chlorite-carbonate-altered shear zones, is anomalous in Ag, As, Bi, Co, Mo, Te, Tl, and W. Anomalies of Ag, As, Bi, Te, and W tend to follow the fault zones, suggesting potential for lode-Au deposits. Soil anomalies of Co, Mo, and Tl appear to follow northwest-striking structures that cross the shear zones, suggesting that Thunder Bay-type mineralization may have overprinted earlier mineralization along the shear zones.

Clark, Robert J.; Meier, A.L.; Riddle, G.

1990-01-01

223

Global Horizontal Irradiance Anomalies in Long Term Series Over India  

NASA Astrophysics Data System (ADS)

India has a high potential for solar energy applications due to its geographic position within the Sun Belt and the large number of cloudless days in many regions of the country. However, certain regions of India, particularly those largely populated, can exhibit large aerosol loading in the atmosphere as a consequence of anthropogenic emissions that could have a negative feedback in the solar resource potential. This effect, named as solar dimming, has already been observed in India, and in some other regions in the world, by some authors using ground data from the last two decades. The recent interest in the promotion of solar energy applications in India highlights the need of extending and improving the knowledge of the solar radiation resources in this country, since most of the long term measurements available correspond to global horizontal radiation (GHI) and most of them are also located big cities or highly populated areas. In addition, accurate knowledge on the aerosol column quantification and on its dynamical behavior with high spatial resolution is particularly important in the case of India, due to their impact on direct normal irradiation. Long term studies of solar irradiation over India can be performed using monthly means of GHI measurements from the Indian Meteorological Department. Ground data are available from 1964 till today through the World Radiation Data Centre that publish these values in the web. This work shows a long term analysis of GHI using anomalies techniques over ten different sites over India. Besides, techniques of linear trends have been applied for to show the evolution over this period. The analysis of anomalies has also found two periods of different behavior. From 1964 till 1988 the anomalies observed were positive and the last 20 years seems to be a period of negative anomalies. The results exhibit a decreasing trend and negative anomalies confirming thus the darkening effect already reported by solar dimming studies. This observation is also consequent with solar dimming effect, apparently increased during the last two decades due to the increase of aerosol loading in the atmosphere. These results remark the important of having accurate knowledge of atmospheric aerosol loading and its dynamics over India with high spatial resolution in the framework of solar energy deployment in the country. It is worth to mention that greater anomalies and a noticeable decreasing trend found in Calcutta could be correlated with the highly population rate, and thus the greater the population density of the area the greater the negative anomalies and the decreasing trend of solar irradiation monthly means.

Cony, Marco; Liria, Juan; Weisenberg, Ralf; Serrano, Enrique

2014-05-01

224

Crustal Magnetic Field Anomalies and Global Tectonics  

NASA Astrophysics Data System (ADS)

A wide variety of evidence suggests that the ruling isochron (geomagnetic polarity versus age) hypothesis of marine magnetic lineations has no merit - undermining therefore one of the central tenets of plate tectonics. Instead, variable induction by the ambient geomagnetic field is likely to be the principal agent for mega-scale crustal magnetic features - in both oceanic and continental settings. This revitalizes the fault-controlled susceptibility-contrast model of marine magnetic lineations, originally proposed in the late 1960s. Thus, the marine magnetic 'striping' may be ascribed to tectonic shearing and related, but variable, disintegration of the original iron-oxide mineralogy, having developed primarily along one of the two pan-global sets of orthogonal fractures and faults. In this way, fault zones (having the more advanced mineral alteration) would be characterized by relatively low susceptibility, while more moderately affected crustal sections (located between principal fault zones) would be likely to have less altered oxide mineralogy and therefore higher magnetic susceptibility. On this basis, induction by the present geomagnetic field is likely to produce oscillating magnetic field anomalies with axis along the principal shear grain. The modus operandi of the alternative magneto-tectonic interpretation is inertia-driven wrenching of the global Alpine age palaeo-lithosphere - triggered by changes in Earth's rotation. Increasing sub-crustal loss to the upper mantle during the Upper Mesozoic had left the ensuing Alpine Earth in a tectonically unstable state. Thus, sub-crustal eclogitization and associated gravity-driven delamination to the upper mantle led to a certain degree of planetary acceleration which in turn gave rise to latitude-dependent, westward inertial wrenching of the global palaeo-lithosphere. During this process, 1) the thin and mechanically fragile oceanic crust were deformed into a new type of broad fold belts, and 2) the continents were subjected to relative 'in situ' rotations (mostly moderate). Examples of marine magnetic lineations with landward continuation along prominent transcurrent fault zones, and the fact that striped marine magnetic anomalies may display orthogonal networks - concordant with the ubiquitous system of rectilinear fractures, faults and joints - corroborate the wrench tectonic interpretation of crustal field anomalies.

Storetvedt, Karsten

2014-05-01

225

Strictly anomaly mediated supersymmetry breaking  

NASA Astrophysics Data System (ADS)

We consider an extension of the minimal supersymmetric Standard Model with anomaly mediation as the only source of supersymmetry breaking, and the tachyonic slepton problem solved by a gauged U(1) symmetry. The extra gauge symmetry is broken at high energies in a manner preserving supersymmetry, while also introducing both the seesaw mechanism for neutrino masses, and the Higgs ?-term. We call the model strictly anomaly mediated supersymmetry breaking. We present typical spectra for the model and compare them with those from so-called minimal anomaly mediated supersymmetry breaking. We find a Standard Model-like Higgs of mass 125 GeV with a gravitino mass of 140 TeV and tan??=16. However, the muon anomalous magnetic moment is 3? away from the experimental value. The model naturally produces a period of hybrid inflation, which can exit to a false vacuum characterized by large Higgs vacuum expectation values, reaching the true ground state after a period of thermal inflation. The scalar spectral index is reduced to approximately 0.975, and the correct abundance of neutralino dark matter can be produced by decays of thermally produced gravitinos, provided the gravitino mass (and hence the Higgs mass) is high. Naturally light cosmic strings are produced, satisfying bounds from the cosmic microwave background. The complementary pulsar timing and cosmic ray bounds require that strings decay primarily via loops into gravitational waves. Unless the loops are extremely small, the next generation pulsar timing array will rule out or detect the string-derived gravitational radiation background in this model.

Hindmarsh, Mark; Jones, D. R. Timothy

2013-04-01

226

The Effect of Ocean Currents on Sea Surface Temperature Anomalies  

NASA Technical Reports Server (NTRS)

We investigate regional and global-scale correlations between observed anomalies in sea surface temperature and height. A strong agreement between the two fields is found over a broad range of latitudes for different ocean basins. Both time-longitude plots and wavenumber-frequency spectra suggest an advective forcing of SST anomalies by a first-mode baroclinic wave field on spatial scales down to 400 km and time scales as short as 1 month. Even though the magnitude of the mean background temperature gradient is determining for the effectiveness of the forcing, there is no obvious seasonality that can be detected in the amplitudes of SST anomalies. Instead, individual wave signatures in the SST can in some cases be followed over periods of two years. The phase relationship between SST and SSH anomalies is dependent upon frequency and wavenumber and displays a clear decrease of the phase lag toward higher latitudes where the two fields come into phase at low frequencies. Estimates of the damping coefficient are larger than generally obtained for a purely atmospheric feedback. From a global frequency spectrum a damping time scale of 2-3 month was found. Regionally results are very variable and range from 1 month near strong currents to 10 month at low latitudes and in the sub-polar North Atlantic. Strong agreement is found between the first global EOF modes of 10 day averaged and spatially smoothed SST and SSH grids. The accompanying time series display low frequency oscillations in both fields.

Stammer, Detlef; Leeuwenburgh, Olwijn

2000-01-01

227

Gravitational Anomalies and Thermal Hall effect in Topological Insulators  

E-print Network

It has been suggested that a temperature gradient will induce a Leduc-Righi, or thermal Hall, current in the Majorana quasiparticles localized on the surface of class DIII topological insulators, and that the magnitude of this current can be related {\\it via} an Einstein argument to a Hall-like energy flux induced by gravity. We critically examine this idea, and argue that the gravitational Hall effect is more complicated than its familiar analogue. A conventional Hall current is generated by a {\\it uniform} electric field, but computing the flux from the gravitational Chern-Simons functional shows that gravitational field {\\it gradients} - i.e. tidal forces - are needed to induce a energy-momentum flow. We relate the surface energy-momentum flux to a domain-wall gravitational anomaly {\\it via} the Callan-Harvey inflow mechanism. We stress that the gauge invariance of the combined bulk-plus-boundary theory ensures that the current in the domain wall always experiences a "covariant" rather than "consistent" anomaly. We use this observation to confirm that the tidally induced energy-momentum current exactly accounts for the covariant gravitational anomaly in $(1+1)$ dimensional domain-wall fermions. The same anomaly arises whether we write the Chern-Simons functional in terms of the Christofflel symbol or in terms of the the spin connection.

Michael Stone

2012-01-19

228

MAGSAT anomaly field inversion and interpretation for the US  

NASA Technical Reports Server (NTRS)

Long wavelength anomalies in the total magnetic field measured by MAGSAT over the United States and adjacent areas are inverted to an equivalent layer crustal magnetization distribution. The model is based on an equal area dipole grid at the Earth's surface. Model resolution, defined as the closest dipole spacing giving a solution having physical significance, is about 220 km for MAGSAT data in the elevation range 300-500 km. The magnetization contours correlate well with large scale tectonic provinces. A higher resolution (200 km) model based on relatively noise free synthetic "pseudodata" is also presented. Magnetic anomaly component data measured by MAGSAT is compared with synthetic anomaly component fields arising from an equivalent source dipole array at the Earth's surface generated from total field anomaly data alone. An excellent inverse correlation between apparent magnetization and heat flow in the western U.S. is demonstrated. A regional heat flow map which is presented and compared with published maps, predicts high heat flow in Nebraska and the Dakotas, suggesting the presence of a "blind" geothermal area of regional extent.

Mayhew, M. A. (principal investigator)

1982-01-01

229

TIR Anomalies Scaling Using the Earthquake Preparation Area Concept  

NASA Astrophysics Data System (ADS)

Surface Thermal Infrared (TIR) satellite observations in seismogenic areas demonstrated their potential in the short-term earthquake prediction applications. Different types of Robust Satellite data analysis Technique (RST) were proposed which provides a statistically based definition of "TIR anomalies" and a suitable method for their identification even in very different local (e.g. related to atmosphere and/or surface) and observational (e.g. related to time/season, but also to solar and satellite zenithal angles) conditions. It was discovered that the spatial scale of anomalies has relation with the magnitude of upcoming seismic event. At the same time the concept of earthquake preparation area (or earthquake activation zone) exist for more than 40 years in different formulations (for example, Dobrovolsky et al., 1979, and Bowman et al., 1998). In this study we compared the size of surface TIR anomalies in the form of RETIRA index with the size of earthquake preparation area for several earthquakes in different areas of the globe with different magnitude and found that their size and spatial distribution perfectly fit to the earthquake preparation area except smaller earthquakes M<5 where the observed TIR anomaly is larger in size than the formal determination.

Pulinets, S. A.; Tramutoli, V.; Genzano, N.; Yudin, I.

2013-05-01

230

Diffusivity anomaly in modified Stillinger-Weber liquids  

SciTech Connect

By modifying the tetrahedrality (the strength of the three body interactions) in the well-known Stillinger-Weber model for silicon, we study the diffusivity of a series of model liquids as a function of tetrahedrality and temperature at fixed pressure. Previous work has shown that at constant temperature, the diffusivity exhibits a maximum as a function of tetrahedrality, which we refer to as the diffusivity anomaly, in analogy with the well-known anomaly in water upon variation of pressure at constant temperature. We explore to what extent the structural and thermodynamic changes accompanying changes in the interaction potential can help rationalize the diffusivity anomaly, by employing the Rosenfeld relation between diffusivity and the excess entropy (over the ideal gas reference value), and the pair correlation entropy, which provides an approximation to the excess entropy in terms of the pair correlation function. We find that in the modified Stillinger-Weber liquids, the Rosenfeld relation works well above the melting temperatures but exhibits deviations below, with the deviations becoming smaller for smaller tetrahedrality. Further we find that both the excess entropy and the pair correlation entropy at constant temperature go through maxima as a function of the tetrahedrality, thus demonstrating the close relationship between structural, thermodynamic, and dynamical anomalies in the modified Stillinger-Weber liquids.

Sengupta, Shiladitya [TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500089 (India)] [TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500089 (India); Vasisht, Vishwas V. [Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur Campus, Bangalore 560064 (India)] [Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur Campus, Bangalore 560064 (India); Sastry, Srikanth [TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500089 (India) [TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500089 (India); Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur Campus, Bangalore 560064 (India)

2014-01-28

231

A RE-INTRODUCTION TO ANOMALIES OF CRITICALITY  

SciTech Connect

In 1974, a small innocuous document was submitted to the American Nuclear Society's Criticality Safety Division for publication that would have lasting impacts on this nuclear field The author was Duane Clayton, manager of the Battelle Pacific Northwest National Laboratory's Critical Mass Lab, the world's preeminent reactor critical experimenter with plutonium solutions. The document was entitled, 'Anomalies of Criticality'. 'Anomalies...' was a compilation of more than thirty separate and distinct examples of departures from what might be commonly expected in the field of nuclear criticality. Mr. Clayton's publication was the derivative of more than ten thousand experiments and countless analytical studies conducted world-wide on every conceivable reactor system imaginable: from fissile bearing solutions to solids, blocks to arrays of fuel rods, low-enriched uranium oxide systems to pure plutonium and highly enriched uranium systems. After publication, the document was commonly used within the nuclear fuel cycle and reactor community to train potential criticality/reactor analysts, experimenters and fuel handlers on important things for consideration when designing systems with critically 'safe' parameters in mind The purpose of this paper is to re-introduce 'Anomalies of Criticality' to the current Criticality Safety community and to add new 'anomalies' to the existing compendium. By so doing, it is the authors' hope that a new generation of nuclear workers and criticality engineers will benefit from its content and might continue to build upon this work in support of the nuclear renaissance that is about to occur.

PUIGH RJ

2009-09-09

232

Dendritic Anomalies in Disorders Associated with Mental Retardation  

Microsoft Academic Search

Dendritic abnormalities are the most consistent anatomical correlates of mental retardation (MR). Earliest descriptions included dendritic spine dysgenesis, which was first associated with unclassified MR, but can also be found in genetic syndromes associated with MR. Genetic disorders with well-defined dendritic anomalies involving branches and\\/or spines include Down, Rett and fragile-X syndromes. Cytoarchitectonic analyses also suggest dendritic pathology in Williams

Walter E. Kaufmann; Hugo W. Moser

2000-01-01

233

The longevity of the South Pacific isotopic and thermal anomaly  

USGS Publications Warehouse

The South Pacific is anomalous in terms of the Sr, Nd, and Pb isotope ratios of its hot spot basalts, a thermally enhanced lithosphere, and possibly a hotter mantle. We have studied the Sr, Nd, and Pb isotope characteristics of 12 Cretaceous seamounts in the Magellans, Marshall and Wake seamount groups (western Pacific Ocean) that originated in this South Pacific Isotopic and Thermal Anomaly (SOPITA). The range and values of isotope ratios of the Cretaceous seamount data are similar to those of the island chains of Samoa, Tahiti, Marquesas and Cook/Austral in the SOPITA. These define two major mantle components suggesting that isotopically extreme lavas have been produced at SOPITA for at least 120 Ma. Shallow bathymetry, and weakened lithosphere beneath some of the seamounts studied suggests that at least some of the thermal effects prevailed during the Cretaceous as well. These data, in the context of published data, suggest: 1. (1)|SOPITA is a long-lived feature, and enhanced heat transfer into the lithosphere and isotopically anomalous mantle appear to be an intrinsic characteristic of the anomaly. 2. (2)|The less pronounced depth anomaly during northwesterly plate motion suggests that some of the expressions of SOPITA may be controlled by the direction of plate motion. Motion parallel to the alignment of SOPITA hot spots focusses the heat (and chemical input into the lithosphere) on a smaller cross section than oblique motion. 3. (3)|The lithosphere in the eastern and central SOPITA appears to have lost its original depleted mantle characteristics, probably due to enhanced plume/lithosphere interaction, and it is dominated by isotopic compositions derived from plume materials. 4. (4)|We speculate (following D.L. Anderson) that the origin of the SOPITA, and possibly the DUPAL anomaly is largely due to focussed subduction through long periods of the geological history of the earth, creating a heterogeneous distribution of recycled components in the lower mantle. ?? 1991.

Staudigel, H.; Park, K.-H.; Pringle, M.; Rubenstone, J.L.; Smith, W.H.F.; Zindler, A.

1991-01-01

234

Hot Flow Anomalies at Venus  

NASA Technical Reports Server (NTRS)

We present a multi-instrument study of a hot flow anomaly (HFA) observed by the Venus Express spacecraft in the Venusian foreshock, on 22 March 2008, incorporating both Venus Express Magnetometer and Analyzer of Space Plasmas and Energetic Atoms (ASPERA) plasma observations. Centered on an interplanetary magnetic field discontinuity with inward convective motional electric fields on both sides, with a decreased core field strength, ion observations consistent with a flow deflection, and bounded by compressive heated edges, the properties of this event are consistent with those of HFAs observed at other planets within the solar system.

Collinson, G. A.; Sibeck, David Gary; Boardsen, Scott A.; Moore, Tom; Barabash, S.; Masters, A.; Shane, N.; Slavin, J.A.; Coates, A.J.; Zhang, T. L.; Sarantos, M.

2012-01-01

235

BRF1 mutations alter RNA polymerase III-dependent transcription and cause neurodevelopmental anomalies.  

PubMed

RNA polymerase III (Pol III) synthesizes tRNAs and other small noncoding RNAs to regulate protein synthesis. Dysregulation of Pol III transcription has been linked to cancer, and germline mutations in genes encoding Pol III subunits or tRNA processing factors cause neurogenetic disorders in humans, such as hypomyelinating leukodystrophies and pontocerebellar hypoplasia. Here we describe an autosomal recessive disorder characterized by cerebellar hypoplasia and intellectual disability, as well as facial dysmorphic features, short stature, microcephaly, and dental anomalies. Whole-exome sequencing revealed biallelic missense alterations of BRF1 in three families. In support of the pathogenic potential of the discovered alleles, suppression or CRISPR-mediated deletion of brf1 in zebrafish embryos recapitulated key neurodevelopmental phenotypes; in vivo complementation showed all four candidate mutations to be pathogenic in an apparent isoform-specific context. BRF1 associates with BDP1 and TBP to form the transcription factor IIIB (TFIIIB), which recruits Pol III to target genes. We show that disease-causing mutations reduce Brf1 occupancy at tRNA target genes in Saccharomyces cerevisiae and impair cell growth. Moreover, BRF1 mutations reduce Pol III-related transcription activity in vitro. Taken together, our data show that BRF1 mutations that reduce protein activity cause neurodevelopmental anomalies, suggesting that BRF1-mediated Pol III transcription is required for normal cerebellar and cognitive development. PMID:25561519

Borck, Guntram; Hög, Friederike; Dentici, Maria Lisa; Tan, Perciliz L; Sowada, Nadine; Medeira, Ana; Gueneau, Lucie; Thiele, Holger; Kousi, Maria; Lepri, Francesca; Wenzeck, Larissa; Blumenthal, Ian; Radicioni, Antonio; Schwarzenberg, Tito Livio; Mandriani, Barbara; Fischetto, Rita; Morris-Rosendahl, Deborah J; Altmüller, Janine; Reymond, Alexandre; Nürnberg, Peter; Merla, Giuseppe; Dallapiccola, Bruno; Katsanis, Nicholas; Cramer, Patrick; Kubisch, Christian

2015-02-01

236

Sea level anomalies exacerbate beach erosion  

NASA Astrophysics Data System (ADS)

level anomalies are intra-seasonal increases in water level forced by meteorological and oceanographic processes unrelated to storms. The effects of sea level anomalies on beach morphology are unknown but important to constrain because these events have been recognized over large stretches of continental margins. Here, we present beach erosion measurements along Onslow Beach, a barrier island on the U.S. East Coast, in response to a year with frequent sea level anomalies and no major storms. The anomalies enabled extensive erosion, which was similar and in most places greater than the erosion that occurred during a year with a hurricane. These results highlight the importance of sea level anomalies in facilitating coastal erosion and advocate for their inclusion in beach-erosion models and management plans. Sea level anomalies amplify the erosive effects of accelerated sea level rise and changes in storminess associated with global climate change.

Theuerkauf, Ethan J.; Rodriguez, Antonio B.; Fegley, Stephen R.; Luettich, Richard A.

2014-07-01

237

The impact of devegetated dune fields on North American climate during the late Medieval Climate Anomaly  

NASA Astrophysics Data System (ADS)

During the Medieval Climate Anomaly, North America experienced severe droughts and widespread mobilization of dune fields that persisted for decades. We use an atmosphere general circulation model, forced by a tropical Pacific sea surface temperature reconstruction and changes in the land surface consistent with estimates of dune mobilization (conceptualized as partial devegetation), to investigate whether the devegetation could have exacerbated the medieval droughts. Presence of devegetated dunes in the model significantly increases surface temperatures, but has little impact on precipitation or drought severity, as defined by either the Palmer Drought Severity Index or the ratio of precipitation to potential evapotranspiration. Results are similar to recent studies of the 1930s Dust Bowl drought, suggesting bare soil associated with the dunes, in and of itself, is not sufficient to amplify droughts over North America.

Cook, B. I.; Seager, R.; Miller, R. L.

2011-07-01

238

The Impact of Devegetated Dune Fields on North American Climate During the Late Medieval Climate Anomaly  

NASA Technical Reports Server (NTRS)

During the Medieval Climate Anomaly, North America experienced severe droughts and widespread mobilization of dune fields that persisted for decades. We use an atmosphere general circulation model, forced by a tropical Pacific sea surface temperature reconstruction and changes in the land surface consistent with estimates of dune mobilization (conceptualized as partial devegetation), to investigate whether the devegetation could have exacerbated the medieval droughts. Presence of devegetated dunes in the model significantly increases surface temperatures, but has little impact on precipitation or drought severity, as defined by either the Palmer Drought Severity Index or the ratio of precipitation to potential evapotranspiration. Results are similar to recent studies of the 1930s Dust Bowl drought, suggesting bare soil associated with the dunes, in and of itself, is not sufficient to amplify droughts over North America.

Cook, B. I.; Seager, R.; Miller, R. L.

2011-01-01

239

Procedures and results related to the direct determination of gravity anomalies from satellite and terrestrial gravity data  

NASA Technical Reports Server (NTRS)

The equations needed for the incorporation of gravity anomalies as unknown parameters in an orbit determination program are described. These equations were implemented in the Geodyn computer program which was used to process optical satellite observations. The arc dependent parameter unknowns, 184 unknown 15 deg and coordinates of 7 tracking stations were considered. Up to 39 arcs (5 to 7 days) involving 10 different satellites, were processed. An anomaly solution from the satellite data and a combination solution with 15 deg terrestrial anomalies were made. The limited data samples indicate that the method works. The 15 deg anomalies from various solutions and the potential coefficients implied by the different solutions are reported.

Rapp, R. H.

1974-01-01

240

Abnormal electroretinogram associated with developmental brain anomalies.  

PubMed Central

PURPOSE: We have encountered abnormal ERGs associated with optic nerve hypoplasia, macular, optic nerve and chorioretinal colobomata and developmental brain anomalies. Brain anomalies include cortical dysgenesis, lissencephaly, porencephaly, cerebellar and corpus callosum hypoplasia. We describe six exemplar cases. METHODS: Scotopic and photopic ERGs adherent to international standards were performed as well as photopic ERGs to long-duration stimuli. CT or MRI studies were also done. The ERGs were compared to age-matched normal control subjects. RESULTS: ERG changes include reduced amplitude b-waves to blue and red stimuli under scotopic testing conditions. Implicit times were often delayed. The photopic responses also showed reduced amplitude a- and b-waves with implicit time delays. The long-duration photopic ERG done in one case shows attenuation of both ON- and OFF-responses. CONCLUSIONS: Common underlying developmental genetic or environmental unifying casualties are speculated to be at fault in causing these cases of associated retinal and brain abnormalities. No single etiology is expected. Multiple potential causes acting early in embryogenesis effecting neuronal induction, migration and differentiation are theorized. These occur at a time when brain and retinal cells are sufficiently undifferentiated to be similarly effected. We call these cases examples of Brain Retina Neuroembryodysgenesis (BRNED). Homeobox and PAX genes with global neuronal developmental influences are gene candidates to unify the observed disruption of brain and retinal cell development. The ERG can provide a valuable clinical addition in understanding and ultimately classifying these disorders. Images FIGURE 1 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 PMID:8719676

Cibis, G W; Fitzgerald, K M

1995-01-01

241

Io's Thermal Anomalies: Clues to their origins from comparison of ground based observations between 1 and 20 micrometers  

NASA Technical Reports Server (NTRS)

The observed frequency of occurrence of high temperature events, the linking of high and lower temperature thermal anomalies, and observed stability of volcanic regions since Voyager suggests that high temperature silicate eruptions could support the entire observed population of cooler temperature anomalies.

Blaney, Diana L.; Veeder, Glenn J.; Matson, Dennis L.; Johnson, Torrence V.; Goguen, Jay D.

1997-01-01

242

Chiral Anomaly in Euclidean (2+1)DIMENSIONAL Space and AN Application to the Quantum Hall Effect  

Microsoft Academic Search

The chiral anomaly in (2+1)-dimensions and its relationship to the zero mode of the Dirac equation in the massless case is studied. Solutions are obtained for the Dirac equation under a vector potential which generates a constant magnetic field. It is shown that there is an anomaly term associated with the corresponding chiral transformation. It can be calculated by using

Paul Bracken

2008-01-01

243

Pancake kidney: A rare developmental anomaly  

PubMed Central

There are many developmental anomalies of the kidney. Pancake kidney is one of the rarest types of renal ectopia. We report a case of pancake kidney which was detected incidentally while treating a female patient for a urinary tract infection. Although urinary system anomalies often coexist with malformations of other organs and systems, no associated anomalies could be detected in this case. Pancake kidney is usually managed by surgery, but this case was managed conservatively without any complication. PMID:25024805

Tiwari, Alok Kumar; Choudhary, Anil Kumar; Khowal, Hemant; Chaudhary, Poras; Arora, Mohinder. P.

2014-01-01

244

Anomaly polynomial of general 6D SCFTs  

NASA Astrophysics Data System (ADS)

We describe a method to determine the anomaly polynomials of general 6D mathcal {N}={(2,0)} and mathcal {N}={(1,0)} superconformal field theories (SCFTs), in terms of the anomaly matching on their tensor branches. This method is almost purely field theoretical, and can be applied to all known 6D SCFTs. We demonstrate our method in many concrete examples, including mathcal {N}={(2,0)} theories of arbitrary type and the theories on M5 branes on asymptotically locally Euclidean (ALE) singularities, reproducing the N^3 behavior. We check the results against the anomaly polynomials computed M-theoretically via the anomaly inflow.

Ohmori, Kantaro; Shimizu, Hiroyuki; Tachikawa, Yuji; Yonekura, Kazuya

2014-10-01

245

The magnetic anomaly of the Ivreazone  

NASA Technical Reports Server (NTRS)

A magnetic field survey was made in the Ivreazone in 1969/70. The results were: significant anomaly of the vertical intensity is found. It follows the basic main part of the Ivrea-Verbano zone and continues to the south. The width of the anomaly is about 10 km, the maximum measures about +800 gamma. The model interpretation shows that possibly the anomaly belongs to an amphibolitic body, which in connection with the Ivrea-body was found by deep seismic sounding. Therefore, the magnetic anomaly provides further evidence for the conception that the Ivrea-body has to be regarded as a chip of earthmantle material pushed upward by tectonic processes.

Albert, G.

1979-01-01

246

A note on some methods suitable for verifying and correcting the prediction of climatic anomaly  

Microsoft Academic Search

The weighted correlation coefficient of the predicted and observed anomalies and the ratio of the weighted norm of predicted\\u000a anomaly to the observed one, both together, are suggested to be suitable for the estimating of the correctness of climate\\u000a prediction. The former shows the similarity of the two patterns, and the later indicates the correctness of the predicted\\u000a intensity of

Qingcun Zeng; Banglin Zhang; Chongguang Yuan; Peisheng Lu; Fanglin Yang; Xu Li; Huijun Wang

1994-01-01

247

Modeling of North Pacific Climate Variability Forced by Oceanic Heat Flux Anomalies  

Microsoft Academic Search

Potential predictability of low-frequency climate changes in the North Pacific depends on two main factors. The first is the sensitivity of the atmosphere to ocean-induced anomalies at the sea surface in midlatitudes. The second is the degree of teleconnectivity of the tropical low-frequency variability to midlatitudes. In contrast to the traditional approach of prescribing sea surface temperature (SST) anomalies, the

Elena Yulaeva; Niklas Schneider; David W. Pierce; Tim P. Barnett

2001-01-01

248

Phase diagram and thermodynamic and dynamic anomalies in a pure repulsive model  

NASA Astrophysics Data System (ADS)

Using Monte Carlo simulations a lattice gas model with only repulsive interactions was checked for the presence of anomalies. We show that this system exhibits the density (temperature of maximum density—TMD) and diffusion anomalies as present in liquid water. These anomalous behaviors exist in the region of the chemical potential vs temperature phase diagram where two structured phases are present. A fragile-to-strong dynamic transition is also observed in the vicinity of the TMD line.

Bertolazzo, Andressa A.; Barbosa, Marcia C.

2014-06-01

249

SST anomalies variability ad El Nino south oscillation in southwestern Atlantic  

NASA Astrophysics Data System (ADS)

Kaplan OSxbNCEP data set 1856-2000 is used to study variability of the Sea Surface Temperature (SST) anomalies in the Southern Atlantic Ocean (17.5-57.5°S x 32.5-62.5°W). The 48 events of El-Niño and 47 La Niña events were selected for 145 years period from classification by different authors. In the examination of the monthly SST anomalies at 9 points of Southwestern Atlantic were found differences between El Niño and La Niña years in pre El Niño and La Niña winter period (from April through October). On an average, the El Niño events are characterised by negative SST anomalies at the Malvinas current and positive SST anomalies at the Brazil current. On the contrary, La Niña events are characterised by anomaly cold Brazil current and warm Malvinas current. Pre El Niño Southern Oscillation (PreENSO) are suggested for the moment of a decrease of SST anomalies in Malvinas current. Three types: early-April, middle -June and later-October (PreENSO I, II, and III respectively) were established. The yearly type precedes the El Niño in following year, the later one precedes strong El Niño events at fin of the current year (e.g. 1982/83 and 1997/98), and type of the PreENSO in June with the negative SST anomalies until September precedes the El Niño in December. Using monthly SST anomalies in Southwestern Atlantic were computed mathematical indicators of ENSO events. These indicators are suggested for reconstruction of the weak, moderate strength and strong La Niña episodies for the 1868-2000 period. We use least square method to study correlation between events in each period, and SSTA. El Niño (except the strongest events) could be predicted three to six months in advance from knowledge of time-space SST anomalies variability in Southwestern Atlantic.

Severov, D.; Mordecki, E.; Pshennikov, V.

250

Spreading rate dependence of gravity anomalies along oceanic transform faults.  

PubMed

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. PMID:17625563

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

2007-07-12

251

Atmospheric and Surface Forcings on Recent Arctic Temperature Anomalies  

NASA Astrophysics Data System (ADS)

The Arctic has seen outsized warming over the past decade (2000-2009) relative to lower latitudes. This reflects the combined effects of: 1) a general background warming interpreted as part of the planet’s response to positive radiative forcing; 2) anomalies in atmospheric circulation; 3) changes in characteristics of the surface, in particular, reduced sea ice concentration and higher SSTs compared to climatology. Background radiative forcing is suggested from the widespread warming that is present for all seasons and for temperature anomalies stratified by each of the four cardinal wind directions. Anomalies in atmospheric circulation introduce spatial structure to seasonal temperature anomaly patterns. For example, strong positive anomalies centered between Svalbard and Novaya Zemlya in winter owe their existence in part to an anomalous southerly wind component. Circulation also explains local cooling, such as seen during spring over the quadrant from to date line eastward to 90 deg.W. The effects of reduced ice concentration are most apparent as regional “hot spots” in the temperature anomaly field. Surface forcing is evident from the stronger warming at the surface compared to the 925 hPa level. Processes can be mutually supporting. The best example is the region of positive temperature anomalies between Svalbard and Novaya Zemlya in winter - while both wind stress and warmth associated with anomalous southerly winds help to maintain open water, vertical heat fluxes from the open water help to keep the atmosphere warm. With regard to the trajectory of the Arctic system through the 21st century, an important issue is how the effects of atmospheric warming due to reduced sea ice concentration and higher SSTs will be spread out by winds to affect surrounding regions, acting as a feedback to foster more ice melt and reduce ice growth, or leading to enhanced warming over land affecting vegetation and soil temperature regimes. For the period 2000-2009, effects of winds in “spreading out the heat” are most apparent over the Atlantic side of the Arctic in winter and over the central Arctic Ocean in autumn.

Serreze, M. C.; Barrett, A. P.; Cassano, J. J.

2010-12-01

252

Implementation of a General Real-Time Visual Anomaly Detection System Via Soft Computing  

NASA Technical Reports Server (NTRS)

The intelligent visual system detects anomalies or defects in real time under normal lighting operating conditions. The application is basically a learning machine that integrates fuzzy logic (FL), artificial neural network (ANN), and generic algorithm (GA) schemes to process the image, run the learning process, and finally detect the anomalies or defects. The system acquires the image, performs segmentation to separate the object being tested from the background, preprocesses the image using fuzzy reasoning, performs the final segmentation using fuzzy reasoning techniques to retrieve regions with potential anomalies or defects, and finally retrieves them using a learning model built via ANN and GA techniques. FL provides a powerful framework for knowledge representation and overcomes uncertainty and vagueness typically found in image analysis. ANN provides learning capabilities, and GA leads to robust learning results. An application prototype currently runs on a regular PC under Windows NT, and preliminary work has been performed to build an embedded version with multiple image processors. The application prototype is being tested at the Kennedy Space Center (KSC), Florida, to visually detect anomalies along slide basket cables utilized by the astronauts to evacuate the NASA Shuttle launch pad in an emergency. The potential applications of this anomaly detection system in an open environment are quite wide. Another current, potentially viable application at NASA is in detecting anomalies of the NASA Space Shuttle Orbiter's radiator panels.

Dominguez, Jesus A.; Klinko, Steve; Ferrell, Bob; Steinrock, Todd (Technical Monitor)

2001-01-01

253

Modeling Multiple Time Series for Anomaly Detection  

Microsoft Academic Search

Our goal is to generate comprehensible and accurate models from multiple time series for anomaly detection. The models need to produce anomaly scores in an online man- ner for real-life monitoring tasks. We introduce three algo- rithms that work in a constructed feature space and evaluate them with a real data set from the NASA shuttle program. Our offline and

Philip K. Chan; Matthew V. Mahoney

2005-01-01

254

Disparity : scalable anomaly detection for clusters.  

SciTech Connect

In this paper, we describe disparity, a tool that does parallel, scalable anomaly detection for clusters. Disparity uses basic statistical methods and scalable reduction operations to perform data reduction on client nodes and uses these results to locate node anomalies. We discuss the implementation of disparity and present results of its use on a SiCortex SC5832 system.

Desai, N.; Bradshaw, R.; Lusk, E.

2008-01-01

255

American depository receipts and calendar anomalies  

Microsoft Academic Search

This is the first study to examine the presence of calendar anomalies in American Depository Receipts (ADR) returns. Existing literature has documented several calendar anomalies in US and foreign markets. ADRs, however, represent a unique class of securities because they represent the ownership of stock of a foreign firm, but they are traded on US markets. We use the Standard

Janie Casello Bouges; Ravi Jain; Yash R. Puri

2009-01-01

256

Magnetic resonance images of neuronal migration anomalies.  

PubMed

Neuronal migration anomalies are a spectrum of brain malformations caused by insults to migrating neuroblasts during the sixth week to fifth month of gestation. To study the characteristics of MRI findings in migration anomalies, MR images of 36 patients (28 children and 8 adults) with migration anomalies were evaluated. Five patients had lissencephaly, eight had pachygyria, twelve had schizencephaly, six had heterotopias of gray matter, three had hemimegalencephaly, and two had polymicrogyria. The frequency of migration anomalies was 0.51% of all cranial MRI studies and 1.21% of pediatric cranial MRI studies at our hospital. The major clinical presentations of these patients were seizure (64%), development delay (42%), motor deficits (42%) and mental retardation (25%). Twenty-five patients (69%) associated with other brain anomalies, including: other migration anomalies in 12 cases (33%), absence of the septum pellucidum in 10 cases (28%), Dandy-Walker malformation/variant in 5 cases, arachnoid cyst in 4 cases, agenesis of the corpus callosum in 3 cases, holoprosencephaly in 2 cases, mega cisterna magna in 1 case and cephalocele in 1 case. Some of them presented with multiple complicated anomalies. As MR imaging provides superb gray-white matter distinction, details of cortical anatomy and multiplanar capability, it can clearly delineate the detail morphologic changes of the brain caused by neuronal migration disorders as well as the associated anomalies. PMID:9780601

Jaw, T S; Sheu, R S; Liu, G C; Chou, M S

1998-08-01

257

Sources of Near Side Lunar Magnetic Anomalies  

NASA Technical Reports Server (NTRS)

Lunar Prospector magnetometer data has been used to identify a number of nearside magnetic anomalies. Some of the features identified appear to correlate with impact ejecta, supporting a basin ejecta origin to the nearside anomalies. Additional information is contained in the original extended abstract.

Richmond, Nicola C.; Hood, Lon L.; Halekas, J. S.; Mitchell, D. L.; Lin, R. P.; Acuna, M. H.; Binder, A.B.

2002-01-01

258

Classical anomalies for spinning particles  

NASA Astrophysics Data System (ADS)

We discuss the phenomenon of classical anomaly. It is observed for 3D Berezin-Marinov (BM), Barducci-Casalbuoni-Lusanna (BCL) and Cortés-Plyushchay-Velázquez (CPV) pseudoclassical spin particle models. We show that quantum mechanically these different models correspond to the same P, T-invariant system of planar fermions, but the quantum system has global symmetries being not reproducible classically in full in any of the models. We demonstrate that the specific U(1) gauge symmetry characterized by the opposite coupling constants of spin s = + {1}/{2} and s = - {1}/{2} states has a natural classical analog in the CPV model but can be reproduced in the BM and BCL models in an obscure and rather artificial form. We also show that the BM and BCL models quantum mechanically are equivalent in any odd-dimensional space-time, but describe different quantum systems in even space-time dimensions.

Gamboa, Jorge; Plyushchay, Mikhail

1998-02-01

259

Suggested future directions in high-speed transition experimental research  

NASA Technical Reports Server (NTRS)

Historical developments in the area of high-speed experimental transition research are outlined, and future directions in this area as determined by the panel membership are listed. The directions include measurement and modeling of initial disturbance fields, both in ground facilities and flight, for all modes; development of advanced high-speed instrumentation for disturbance field measurements, measurements of the details of receptivity in multitudinous flows; further development and use of high-speed quiet tunnels; stability and transition studies for multitudinous flows; detailed studies of the transitional region for boundary layers, free flows, vortices separated flows, corner flows, etc.; and studies of flow-chemistry effects on transition phenomena. Applied research such areas as the physics of perforated-surface suction stabilization and the resolution of anomalies in the existing high-speed database is also suggested.

Bushnell, Dennis

1990-01-01

260

Altered Orientation and Flight Paths of Pigeons Reared on Gravity Anomalies: A GPS Tracking Study  

PubMed Central

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. PMID:24194860

Blaser, Nicole; Guskov, Sergei I.; Meskenaite, Virginia; Kanevskyi, Valerii A.; Lipp, Hans-Peter

2013-01-01

261

A New, Principled Approach to Anomaly Detection  

SciTech Connect

Intrusion detection is often described as having two main approaches: signature-based and anomaly-based. We argue that only unsupervised methods are suitable for detecting anomalies. However, there has been a tendency in the literature to conflate the notion of an anomaly with the notion of a malicious event. As a result, the methods used to discover anomalies have typically been ad hoc, making it nearly impossible to systematically compare between models or regulate the number of alerts. We propose a new, principled approach to anomaly detection that addresses the main shortcomings of ad hoc approaches. We provide both theoretical and cyber-specific examples to demonstrate the benefits of our more principled approach.

Ferragut, Erik M [ORNL; Laska, Jason A [ORNL; Bridges, Robert A [ORNL

2012-01-01

262

Regional magnetic anomaly constraints on continental rifting  

NASA Technical Reports Server (NTRS)

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.

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

1985-01-01

263

Trends in hemispheric warm and cold anomalies  

NASA Astrophysics Data System (ADS)

a spatial percentile approach, we explore the magnitude of temperature anomalies across the Northern and Southern Hemispheres. Linear trends in spatial percentile series are estimated for 1881-2013, the most recent 30 year period (1984-2013), and 1998-2013. All spatial percentiles in both hemispheres show increases from 1881 to 2013, but warming occurred unevenly via modification of cold anomalies, producing a reduction in spatial dispersion. In the most recent 30 year period, trends also were consistently positive, with warm anomalies having much larger warming rates than those of cold anomalies in both hemispheres. This recent trend has largely reversed the decrease in spatial dispersion that occurred during the twentieth century. While the period associated with the recent slowdown of global warming, 1998-2013, is too brief to estimate trends reliably, cooling was evident in NH warm and cold anomalies during January and February while other months in the NH continued to warm.

Robeson, Scott M.; Willmott, Cort J.; Jones, Phil D.

2014-12-01

264

An impactor origin for lunar magnetic anomalies.  

PubMed

The Moon possesses strong magnetic anomalies that are enigmatic given the weak magnetism of lunar rocks. We show that the most prominent grouping of anomalies can be explained by highly magnetic extralunar materials from the projectile that formed the largest and oldest impact crater on the Moon: the South Pole-Aitken basin. The distribution of projectile materials from a model oblique impact coincides with the distribution of magnetic anomalies surrounding this basin, and the magnetic properties of these materials can account for the intensity of the observed anomalies if they were magnetized in a core dynamo field. Distal ejecta from this event can explain the origin of isolated magnetic anomalies far from this basin. PMID:22403388

Wieczorek, Mark A; Weiss, Benjamin P; Stewart, Sarah T

2012-03-01

265

An Impactor Origin for Lunar Magnetic Anomalies  

NASA Astrophysics Data System (ADS)

The Moon possesses strong magnetic anomalies that are enigmatic given the weak magnetism of lunar rocks. We show that the most prominent grouping of anomalies can be explained by highly magnetic extralunar materials from the projectile that formed the largest and oldest impact crater on the Moon: the South Pole-Aitken basin. The distribution of projectile materials from a model oblique impact coincides with the distribution of magnetic anomalies surrounding this basin, and the magnetic properties of these materials can account for the intensity of the observed anomalies if they were magnetized in a core dynamo field. Distal ejecta from this event can explain the origin of isolated magnetic anomalies far from this basin.

Wieczorek, Mark A.; Weiss, Benjamin P.; Stewart, Sarah T.

2012-03-01

266

Correlations of Lunar Magnetic Anomalies with Geologic Age and Material  

NASA Astrophysics Data System (ADS)

While the moon has is no present-day internally generated magnetic field, widespread coherently magnetized geologic units were observed with Apollo era surface and sub-satellite measurements and more recently with Lunar Prospector. However, unlike at Mars, magnetized lunar units show no clear-cut correlation with age: a few, but not all, basins of Nectarian age (3.92-3.85 Ga) exhibit magnetic anomalies within the basin; some, but not all, basins exhibit magnetic anomalies associated with their ejecta; and most of the crustal magnetization is in a spatially extensive region to the NW of South Pole Aitken. Recent paleomagnetic analyses have been performed on a range of sample types and ages including absolute and relative paleointensity and directional measurements. Collectively, these paleomagnetic results have been used to suggest the existence of a lunar dynamo during the period ~ 3.6 - 4.2 Ga. Various mechanisms that could have produced a dynamo spanning all or part of this time interval are being investigated, such as precession, nutation, and thermally or compositionally-driven core convection. It is also apparent that shock plays an important, although still poorly-understood, role in the magnetic history of the Moon: concentrations of magnetic anomalies correlate with the antipodes of four major impact basins; strong fields at Apollo 16 site those associated with the Reiner Gamma formation are attributed to basin ejecta; experiments have shown shock can demagnetize or remagnetize a material in the absence of a permanent magnetic field. Thus, despite significant recent work, no single data set, experiment, or model provides an unambiguous record of lunar magnetic evolution. A clear understanding regarding the timing of either a permanent global field or the existence of intermittent transient fields is not apparent. Here we focus on the issue of the correlation of crustal magnetic anomalies with geologic age (Copernican, Eratosthenian, Imbrian, Nectarian or Pre-Nectarian) and geologic unit (basin, crater, mare or dark, and terra materials) in an effort to place constraints on the source of magnetizations and the timing of acquisition of remanence. Previous studies have investigated the correlation of magnetization with individual basin age or particular formation units (e.g. Caley Formation) but this has not been extended to the global scale, covered all lunar ages, or expanded beyond correlation with basin materials. Statistical analyses using Lunar Prospector Magnetometer and Electron Reflectometer data quantify the correlation of geologic ages and units with magnetic anomalies. The majority of observable magnetic anomalies are associated with visible surface units having ages that are Imbrian or Nectarian. Magnetic anomalies are statistically more likely to occur in association with crater ejecta and highland material than with basin materials. We discuss whether this global interpretation is representative of magnetic anomalies found NW of South Pole Aitken (SPA) basin, to help determine whether the sources of circum-SPA magnetic anomalies are fundamentally different from those of magnetic anomalies elsewhere on the moon.

Lawrence, K. P.; Johnson, C. L.

2011-12-01

267

On global gravity anomalies and two-scale mantle convection  

NASA Technical Reports Server (NTRS)

The two-scale model of mantle convection developed by Richter and Parsons (1975) predicts that if the depth of the convective layer is about 600 km, then for a plate moving at 10 cm/yr, longitudinal convective rolls will be produced in about 50 million years, and the strike of these rolls indicates the direction of motion of the plate relative to the upper mantle. The paper tests these predictions by examining a new global free air gravity model complete to the 30th degree and order. The free air gravity map developed shows a series of linear positive and negative anomalies (with transverse wavelengths of about 2000 km) spanning the Pacific Ocean, crossing the Pacific rise and striking parallel to the Hawaiian seamounts. It is suggested that the pattern of these anomalies may indicate the presence of longitudinal convective rolls beneath the Pacific plates, a result which tends to support the predictions of Richter and Parsons.

Marsh, B. D.; Marsh, J. G.

1976-01-01

268

Familial craniosynostosis, anal anomalies, and porokeratosis: CAP syndrome.  

PubMed Central

We report on the occurrence of coronal craniosynostosis, anal anomalies, and porokeratosis in two male sibs. A third male sib was phenotypically normal as were the parents. The occurrence of these three clinical features has, to our knowledge, not been reported before. Cutaneous or anal anomalies or both have been reported in a number of syndromes associated with craniosynostosis, including Crouzon, Pfeiffer, Apert, and Beare-Stevenson syndromes. These syndromes are associated with mutations in the fibroblast growth factor receptor genes FGFR1, FGFR2, and FGFR3. They are inherited in an autosomal dominant fashion. In contrast, the cases we report do not carry any of the common FGFR mutations and the pedigree suggests autosomal or X linked recessive inheritance. Images PMID:9733036

Flanagan, N; Boyadjiev, S A; Harper, J; Kyne, L; Earley, M; Watson, R; Jabs, E W; Geraghty, M T

1998-01-01

269

Esthetic dental anomalies as motive for bullying in schoolchildren  

PubMed Central

Facial esthetics, including oral esthetics, can severely affect children's quality-of-life, causing physical, social and psychological impairment. Children and adolescents with esthetic-related dental malformations are potential targets for bullies. This study was aimed to present and discuss patients who suffered from bullying at school and family environment due to esthetic-related teeth anomalies. Providing an adequate esthetic dental treatment is an important step in their rehabilitation when the lack of esthetic is the main source of bullying. After dental treatment, we noted significant improvement in self-esteem, self-confidence, socialization and academic performance of all patients and improvement in parental satisfaction regarding the appearance of their children. It is imperative that both family and school care providers be constantly alert about bullying in order to prevent or interrupt aggressive and discriminatory practices against children and adolescents. Clearly, dental anomalies may be a motive for bullying. PMID:24966759

Scheffel, Débora Lopes Salles; Jeremias, Fabiano; Fragelli, Camila Maria Bullio; dos Santos-Pinto, Lourdes Aparecida Martins; Hebling, Josimeri; de Oliveira, Osmir Batista

2014-01-01

270

New experimental constraints for Hadean zircon source melts from Ce and Eu anomalies in zircon  

NASA Astrophysics Data System (ADS)

A common feature of zircon rare earth element profiles is that they often have enriched chondrite normalized Ce abundances relative to bracketing rare earth elements (REEs) La and Pr. The magnitude of a zircon Ce anomaly is generally attributed to an increase in Ce4+/Ce3+ of the crystallizing medium (Ce4+ is more compatible than Ce3+ in zircon), which is associated with more oxidizing environments. Zircons may also have depleted chondrite normalized Eu abundances relative to Sm and Gd. A negative Eu anomaly may be indicative of more reducing conditions (Eu2+ is incompatible in zircon) or depletion of Eu in the melt from plagioclase prior to or during zircon crystallization. We report experimental data from zircons crystallized in hydrous peralkaline, metaluminous, and peraluminous melts (800-1300oC; 10 kbar) with the oxygen fugacity buffered from ~IW to HM+1 in order to constrain magnitude of zircon Ce and Eu anomalies. Zircon Ce anomalies increase in magnitude with higher oxygen fugacities and lower crystallization temperatures; Eu anomalies are more negative at ~IW vs. NNO for the same temperature and melt composition. Our experiments also show that with the oxygen fugacity buffered at NNO, zircons may have both positive Ce anomalies and negative Eu anomalies. Thus, Eu2+ and Ce4+ may co-exist in terrestrial melts; furthermore, melt depletion of Eu by plagioclase fractionation prior to (or during) zircon crystallization may not be a requisite for the presence of zircon Eu anomalies in (Hadean) zircons. The magnitude of the anomalies is also a function of the melt composition; peraluminous melts yield the largest positive Ce (or negative Eu) anomalies at a given oxygen fugacity and temperature. Extrapolation of our preliminary empirical calibration to the crystallization temperatures of the Jack Hills Hadean zircons (~700oC) suggests the magnitude of Ce anomalies in approximately half of the Hadean zircons cannot be produced in metaluminous or peralkaline melts, even at oxygen fugacities as high as HM+1. However, the magnitude of Ce anomalies in Hadean zircons is within the range of predicted anomalies of our experiments for peraluminous melts, implying that a significant portion of the Hadean zircon population may be derived from peraluminous melts. This result is consistent with muscovite inclusion mineralogy in Hadean zircons (e.g., Hopkins et al., 2008), but does not preclude the possibility of other, less evolved peraluminous source rocks, or some process which leads to significant Ce enrichment (relative to La and/or Pr) in the melt at the time of zircon crystallization.

Trail, D.; Watson, E. B.; Tailby, N.

2010-12-01

271

Associated nonurinary congenital anomalies among infants with congenital anomalies of kidney and urinary tract (CAKUT).  

PubMed

Infants with congenital anomalies of kidney and urinary tract (CAKUT) often have other associated anomalies. The purpose of this investigation was to assess the prevalence and the types of associated anomalies in CAKUT in a defined population from northeastern France. The associated anomalies in CAKUT were collected in all livebirths, stillbirths and terminations of pregnancy during 26 years in 346,831 consecutive births of known outcome in the area covered by our population based registry of congenital anomalies. Of the 1678 infants with CAKUT born during this period (prevalence at birth of 48.4 per 10,000), 563 (34%) had associated anomalies. There were 119 (7%) patients with chromosomal abnormalities including 33 trisomies 18 (2%), and 168 (10%) nonchromosomal recognized dysmorphic conditions. There were no predominant recognized dysmorphic conditions, but VA(C)TER(L) association (3%). However, other recognised dysmorphic conditions were registered including Meckel-Gruber syndrome (2%), and prune belly syndrome (1%). Two hundred seventy six (16%) of the patients had multiple congenital anomalies, non syndromic, non chromosomal (MCA). Anomalies in the musculoskeletal, the digestive, the cardiovascular and the central nervous systems were the most common other anomalies. Prenatal diagnosis was obtained in 71% of dysmorphic syndromes with CAKUT. In conclusion the overall prevalence of associated anomalies, which was one in three infants, emphasizes the need for a thorough investigation of infants with CAKUT. The most commonly associated major nonurinary anomalies involved the musculoskeletal system, followed by the digestive, the cardiovascular and the central nervous systems. A routine screening for other anomalies may be considered in infants and in fetuses with CAKUT. One should be aware that the anomalies associated with CAKUT can be classified into a recognizable anomaly syndrome or pattern in one out of six infants with CAKUT. PMID:24821302

Stoll, Claude; Dott, Beatrice; Alembik, Yves; Roth, Marie-Paule

2014-07-01

272

Spherical Earth analysis and modeling of lithospheric gravity and magnetic anomalies. Ph.D. Thesis - Purdue Univ.  

NASA Technical Reports Server (NTRS)

A comprehensive approach to the lithospheric analysis of potential field anomalies in the spherical domain is provided. It has widespread application in the analysis and design of satellite gravity and magnetic surveys for geological investigation.

Vonfrese, R. R. B.; Hinze, W. J.; Braile, L. W.

1980-01-01

273

A Distance Measure for Attention Focusing and Anomaly Detection in Systems Monitoring  

NASA Technical Reports Server (NTRS)

Any attempt to introduce automation into the monitoring of complex physical systems must start from a robust anomaly detection capability. This task is far from straightforward, for a single definition of what constitutes an anomaly is difficult to come by. In addition, to make the monitoring process efficient, and to avoid the potential for information overload on human operators, attention focusing must also be addressed. When an anomaly occurs, more often than not several sensors are affected, and the partially redundant information they provide can be confusing, particularly in a crisis situation where a response is needed quickly. Previous results on extending traditional anomaly detection techniques are summarized. The focus of this paper is a new technique for attention focusing.

Doyle, R.

1994-01-01

274

Disentangling Hippocampal Shape Anomalies in Epilepsy  

PubMed Central

Drug-resistant temporal lobe epilepsy (TLE) and epileptic syndromes related to malformations of cortical development (MCD) are associated with complex hippocampal morphology. The contribution of volume and position to the overall hippocampal shape in these conditions has not been studied. We propose a surface-based framework to localize volume changes through measurement of Jacobian determinants, and quantify fine-scale position and curvature through a medial axis model. We applied our methodology to T1-weighted 3D volumetric MRI of 88 patients with TLE and 78 patients with MCD, including focal cortical dysplasia (FCD, n?=?29), heterotopia (HET, n?=?40), and polymicrogyria (PMG, n?=?19). Patients were compared to 46 age- and sex-matched healthy controls. Surface-based analysis of volume in TLE revealed severe ipsilateral atrophy mainly along the rostro-caudal extent of the hippocampal CA1 subfield. In MCD, patterns of volume changes included bilateral CA1 atrophy in HET and FCD, and left dentate hypertrophy in all three groups. The analysis of curvature revealed medial bending of the posterior hippocampus in TLE, whereas in MCD there was a supero-medial shift of the hippocampal body. Albeit hippocampal shape anomalies in TLE and MCD result from a combination of volume and positional changes, their nature and distribution suggest different pathogenic mechanisms. PMID:24062718

Kim, Hosung; Mansi, Tommaso; Bernasconi, Neda

2013-01-01

275

Clinical significance of intracranial developmental venous anomalies  

PubMed Central

OBJECTIVES—Venous angiomas, or developmental venous anomalies (DVAs), represent the most often occurring cerebral vascular malformation. The clinical significance of a DVA is, however, at present unclear.?METHODS—A retrospective analysis was carried out on two series of consecutive cranial MRIs performed between January 1990 and August 1996 in a university department of neuroradiology and in a large radiological private practice. The medical records of all patients in whom a DVA was diagnosed were screened to identify the specific complaint which necessitated the imaging procedure.?RESULTS—A total of 67 patients with DVA could be identified. In 12 patients an associated cavernoma was found. The main reason for performing the MRI was the evaluation of seizures or of headaches. In all patients with DVA in whom an intracerebral haemorrhage was diagnosed an associated cavernoma was present at the site of the haemorrhage. None of the 67 patients showed an association between the complaints that led to the MRI and the location of the DVA.?CONCLUSIONS—DVAs do not seem to be associated with a specific clinical presentation. In a significant percentage of cases, however, coexisting cavernomas are found which have a defined bleeding potential and should be treated independently of the DVA. This study supports the hypothesis that DVAs are a congenital abnormality of venous drainage without clinical significance.?? PMID:10407000

Topper, R.; Jurgens, E.; Reul, J.; Thron, A.

1999-01-01

276

The Coronal Abundance Anomalies of M Dwarfs  

NASA Astrophysics Data System (ADS)

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.

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

2012-07-01

277

Gravitational Anomalies in the Solar System?  

E-print Network

Mindful of the anomalous perihelion precession of Mercury discovered by U. Le Verrier in the second half of the nineteenth century and its successful explanation by A. 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 bodies 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 cumulative science, as shown to us by the discovery of Neptune in the first half of the nineteenth century. Moreover, investigations in one of such directions can serendipitously enrich the other one as well. The current status of some alleged gra...

Iorio, Lorenzo

2014-01-01

278

Thermal Infrared Anomalies of Several Strong Earthquakes  

PubMed Central

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. PMID:24222728

Wei, Congxin; Guo, Xiao; Qin, Manzhong

2013-01-01

279

Prevalence of dental anomalies in Indian population  

PubMed Central

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 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. Results: 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%). Conclusion: 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. PMID:24455078

Doni, Bharati; Kaswan, Sumita; Rahman, Farzan

2013-01-01

280

Search for causes of the low epithermal neutron flux anomaly in the Arabia Terra region (Mars)  

NASA Astrophysics Data System (ADS)

A geologic analysis of 274 images acquired by the high-resolution MOC camera onboard the Mars Global Surveyor spacecraft within the Arabia Terra low neutron flux anomaly (which is indicative of an anomalously high abundance of hydrogen: up to 16 wt % of the equivalent amount of water) was performed. Correlation between the enhanced abundance of equivalent water with the presence of dust on the surface was found. Since dust plays a key role in condensation of water from the atmosphere, we suppose that the anomalies could result from the retention of atmospheric moisture. To analyze this suggestion, we performed a theoretical modeling that allowed us to map the planetary-scale distributions of several meteorological parameters responsible for the atmospheric moisture condensation. Two antipodal regions coinciding rather well with the Arabia Terra anomaly and the geographically antipodal anomaly southwest of Olympus Mons were found in the maps. This suggests that the anomalies are rather recent than ancient formations. They were probably formed by a sink of moisture from the atmosphere in the areas where present meteorological conditions support this sink. Geological parameters, primarily the presence of dust, only promote this process. We cannot exclude the possibility that the Martian cryosphere, rather than the atmosphere, supplied the studied anomalies with moisture during their formation: the thermodynamic conditions in the anomaly areas could block the moisture flux from the Martian interior in the upper regolith layer. The moisture coming from the atmosphere or from the interior is likely held as chemically bound water entering into the structure of water-bearing minerals (probably, hydrated magnesium sulfates) directly from the vapor; or the moisture precipitates as frost, penetrates into microfissures, and then is bound in minerals. Probably, another geologic factor—the magnesium sulfate abundance—works in the Arabia Terra anomaly.

Basilevsky, A. T.; Rodin, A. V.; Raitala, J.; Neukum, G.; Werner, S.; Kozyrev, A. S.; Sanin, A. B.; Mitrofanov, I. G.; Head, J. W.; Boynton, W.; Saunders, R. S.

2006-10-01

281

Traffic-Related Air Pollution and Congenital Anomalies in Barcelona  

PubMed Central

Background: A recent meta-analysis suggested evidence for an effect of exposure to ambient air pollutants on risk of certain congenital heart defects. However, few studies have investigated the effects of traffic-related air pollutants with sufficient spatial accuracy. Objectives: We estimated associations between congenital anomalies and exposure to traffic-related air pollution in Barcelona, Spain. Method: Cases with nonchromosomal anomalies (n = 2,247) and controls (n = 2,991) were selected from the Barcelona congenital anomaly register during 1994–2006. Land use regression models from the European Study of Cohorts for Air Pollution Effects (ESCAPE), were applied to residential addresses at birth to estimate spatial exposure to nitrogen oxides and dioxide (NOx, NO2), particulate matter with diameter ? 10 ?m (PM10), 10–2.5 ?m (PMcoarse), ? 2.5 ?m (PM2.5), and PM2.5 absorbance. Spatial estimates were adjusted for temporal trends using data from routine monitoring stations for weeks 3–8 of each pregnancy. Logistic regression models were used to calculate odds ratios (ORs) for 18 congenital anomaly groups associated with an interquartile-range (IQR) increase in exposure estimates. Results: In spatial and spatiotemporal exposure models, we estimated statistically significant associations between an IQR increase in NO2 (12.2 ?g/m3) and coarctation of the aorta (ORspatiotemporal = 1.15; 95% CI: 1.01, 1.31) and digestive system defects (ORspatiotemporal = 1.11; 95% CI: 1.00, 1.23), and between an IQR increase in PMcoarse (3.6 ?g/m3) and abdominal wall defects (ORspatiotemporal = 1.93; 95% CI: 1.37, 2.73). Other statistically significant increased and decreased ORs were estimated based on the spatial model only or the spatiotemporal model only, but not both. Conclusions: Our results overall do not indicate an association between traffic-related air pollution and most groups of congenital anomalies. Findings for coarctation of the aorta are consistent with those of the previous meta-analysis. Citation: Schembari A, Nieuwenhuijsen MJ, Salvador J, de Nazelle A, Cirach M, Dadvand P, Beelen R, Hoek G, Basagaña X, Vrijheid M. 2014. Traffic-related air pollution and congenital anomalies in Barcelona. Environ Health Perspect 122:317–323;?http://dx.doi.org/10.1289/ehp.1306802 PMID:24380957

Nieuwenhuijsen, Mark J.; Salvador, Joaquin; de Nazelle, Audrey; Cirach, Marta; Dadvand, Payam; Beelen, Rob; Hoek, Gerard; Basagaña, Xavier; Vrijheid, Martine

2014-01-01

282

Data Mining for Anomaly Detection  

NASA Technical Reports Server (NTRS)

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.

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

2013-01-01

283

The free-convective anomaly.  

PubMed

Persons exposed to high temperature, or to equivalent environmental factors, have quantifiable reactions, such as reducing the resistance to both heat and moisture flow in skin tissues and clothing needed to maintain thermal equilibrium. The one-to-one relationship between this resistance in the walking person and temperature, with the other factors neutral, is the basis for the apparent temperature scale and the derived heat index. When this approach is taken to assess the thermal environment for a still person exposed to heat in still air, there is a zone of ambient conditions in which there are three solutions to the heat-balance equation. Extraordinary thermal stress occurs, depending slightly on other conditions, at ambient temperatures near 41 degrees C, especially at high humidity, because of the difficulty in carrying sweat vapor from the person when free convection is minimal. This anomaly is examined for a range of ambient vapor pressures and extra radiation. The rapid rise in heat stress when ambient temperature just exceeds body temperature in still conditions may explain the severity of some observed distress. PMID:10409558

Steadman, R G

1999-07-01

284

Numerical investigations of the spreading-rate dependence of anomalous skewness of marine magnetic anomalies due to seafloor spreading  

NASA Astrophysics Data System (ADS)

An improved understanding of the spreading-rate dependence of anomalous skewness from magnetic anomalies due to seafloor spreading will allow for better constraints on apparent polar wander paths, plate reconstructions, and the magnetic and thermal structure of oceanic lithosphere. Anomalous skewness, which is the difference between experimentally determined skewness and skewness expected from simple magnetization models with vertical reversal boundaries, has been observed to vary as a function of spreading rate, decreasing with increasing spreading rate and becoming negligible at spreading half-rates exceeding about 55 mm/a [Roest et al. 1992; Dyment et al. 1994]. In our analysis, we determine model-based estimates of anomalous skewness as a function of spreading rate for each anomaly. We do so by creating many synthetic profiles using the model of Dyment and Arkani-Hamed (1995), which was specifically constructed to produce anomalies with anomalous skewness consistent with observed anomalies. We experimentally determine the phase shift that causes the resulting synthetic magnetic anomaly to best match a profile produced from a "standard" model for anomalies due to seafloor spreading that assumes simple vertical reversal boundaries. We present results for those anomalies between 12r and 33r from which reliable paleomagnetic poles may potentially be determined. Differences in anomalous skewness for different anomalies determined at the same spreading rate can be attributed to the sequence effect, that is, the effect on the shape of a magnetic anomaly above seafloor of a single polarity chron of the magnetization of neighboring blocks of lithosphere magnetized during other chrons. We find that the sequence effect is smaller than we expected with the largest difference being between the results for anomaly 25r and those for anomaly 33r, for which the difference is 14 degrees at a 10 mm/a half-rate. Results for other anomalies lie between these two. We also infer a small outward displacement of the magnetic anomalies, which-like anomalous skewness-decreases with increasing spreading rate and vanishes at half rates exceeding 55 mm/a. We find that results obtained trying to find the best match to the synthetic magnetic anomaly profile are generally similar to results obtained when using the balanced-shoulder criterion for when an anomaly has been successfully deskewed. The values of chron-specific (or anomaly-specific) anomalous skewness that we have determined can be used to reduce the number of adjustable parameters in the determination of paleomagnetic poles from skewness data from three to two, to simply the latitude and longitude of the paleomagnetic pole. Implications for the northward motion of the Pacific Plate will be discussed.

Boswell, S. M.; Zheng, L.; Gordon, R. G.; Dyment, J.

2011-12-01

285

Sensitivity of tropical lowland net primary production to climate anomalies  

NASA Astrophysics Data System (ADS)

While drivers of tropical forest productivity such as edaphic properties (geology, topography) and climate (precipitation, temperature, light) are well established, knowledge on the sensitivity of tropical lowland net primary production to climate anomalies remains scarce. We here investigate tropical lowland forest sites differing in topography and disturbance history to study the response of aboveground net primary production (ANPP) in relation to (1) climate extremes as triggered by El-Niño Southern Oscillation (ENSO), as well as (2) topographic position and (3) land-use history. In general, climate anomalies resulted in decreased precipitation and increased temperature. The production of wood decreased while the production of canopy material increased in years with prolonged periods of drought and elevated temperature. However, the impact strongly depended on local characteristics of the forest sites, such that ANPP was only negatively affected at ridges but not at ravine forest sites. We moreover show that the productivity of primary forests was significantly affected by precipitation and drought, while in secondary forests temperature was the major predictor of ANPP. Our results suggest that site-specific parameters such as topographic position and disturbance history determine the response of tropical lowland forests to climate extremes. Hence we conclude that the impact of climate anomalies on tropical forest productivity is strongly related to local conditions and thus will likely prevent uniform responses of tropical lowland forests to projected global changes.

Hofhansl, Florian; Kobler, Johannes; Drage, Sigrid; Pölz, Eva-Maria; Wanek, Wolfgang

2014-05-01

286

Claycap anomaly detection using hyperspectral remote sensing and lidargrammetric techniques  

NASA Astrophysics Data System (ADS)

Clay capped waste sites are a common method to dispose of the more than 40 million tons of hazardous waste produced in the United States every year (EPA, 2003). Due to the potential threat that hazardous waste poses, it is essential to monitor closely the performance of these facilities. Development of a monitoring system that exploits spectral and topographic changes over hazardous waste sites is presented. Spectral anomaly detection is based upon the observed changes in absolute reflectance and spectral derivatives in centipede grass (Eremochloa ophiuroides) under different irrigation levels. The spectral features that provide the best separability among irrigation levels were identified using Stepwise Discriminant Analyses. The Red Edge Position was selected as a suitable discriminant variable to compare the performance of a global and a local anomaly detection algorithm using a DAIS 3715 hyperspectral image. Topographical anomaly detection is assessed by evaluating the vertical accuracy of two LIDAR datasets acquired from two different altitudes (700 m and 1,200 m AGL) over a clay-capped hazardous site at the Savannah River National Laboratory, SC using the same Optech ALTM 2050 and Cessna 337 platform. Additionally, a quantitative comparison is performed to determine the effect that decreasing platform altitude and increasing posting density have on the vertical accuracy of the LIDAR data collected.

Garcia Quijano, Maria Jose

287

Improving the geological interpretation of magnetic and gravity satellite anomalies  

NASA Technical Reports Server (NTRS)

Quantitative analysis of the geologic component of observed satellite magnetic and gravity fields requires accurate isolation of the geologic component of the observations, theoretically sound and viable inversion techniques, and integration of collateral, constraining geologic and geophysical data. A number of significant contributions were made which make quantitative analysis more accurate. These include procedures for: screening and processing orbital data for lithospheric signals based on signal repeatability and wavelength analysis; producing accurate gridded anomaly values at constant elevations from the orbital data by three-dimensional least squares collocation; increasing the stability of equivalent point source inversion and criteria for the selection of the optimum damping parameter; enhancing inversion techniques through an iterative procedure based on the superposition theorem of potential fields; and modeling efficiently regional-scale lithospheric sources of satellite magnetic anomalies. In addition, these techniques were utilized to investigate regional anomaly sources of North and South America and India and to provide constraints to continental reconstruction. Since the inception of this research study, eleven papers were presented with associated published abstracts, three theses were completed, four papers were published or accepted for publication, and an additional manuscript was submitted for publication.

Hinze, William J.; Braile, Lawrence W.; Vonfrese, Ralph R. B.

1987-01-01

288

Tunguska Genetic Anomaly and Electrophonic Meteors  

NASA Astrophysics Data System (ADS)

One of great mysteries of the Tunguska event is its genetic impact. Some genetic anomalies were reported in the plants, insects and people of the Tunguska region. Remarkably, the increased rate of biological mutations was found not only within the epicenter area, but also along the trajectory of the Tunguska Space Body (TSB). At that no traces of radioactivity were found, which could be reliably associated with the Tunguska event. The main hypotheses about the nature of the TSB, a stony asteroid, a comet nucleus or a carbonaceous chondrite, readily explain the absence of radioactivity but give no clues how to deal with the genetic anomaly. A choice between these hypotheses, as far as the genetic anomaly is concerned, is like to the choice between ``blue devil, green devil and speckled devil'', to quote late Academician N.V. Vasilyev. However, if another mysterious phenomenon, electrophonic meteors, is evoked, the origin of the Tunguska genetic anomaly becomes less obscure.

Silagadze, Z. K.

2005-03-01

289

Reduction of satellite magnetic anomaly data  

NASA Technical Reports Server (NTRS)

Analysis of global magnetic anomaly maps derived from satellite data is facilitated by inversion to the equivalent magnetization in a constant thickness magnetic crust or, equivalently, by reduction to the pole. Previous inversions have proven unstable near the geomagnetic equator. The instability results from magnetic moment distributions which are admissible in the inversion solution but which make only small contribution to the computed values of anomaly field. Their admissibility in the solution could result from noisy or incomplete data or from small poorly resolved anomalies. The resulting magnetic moments are unrealistically large and oscillatory. Application of the method of principal components (e.g. eigenvalue decomposition and selective elimination of less significant eigenvectors) is proposed as a way of overcoming the instability and the method is demonstrated by applying it to the region around the Bangui anomaly in Central Africa.

Slud, E. V.; Smith, P. J.; Langel, R. A.

1984-01-01

290

Understanding Magnetic Anomalies and Their Significance.  

ERIC Educational Resources Information Center

Describes a laboratory exercise testing the Vine-Matthews-Morley hypothesis of plate tectonics. Includes 14 questions with explanations using graphs and charts. Provides a historical account of the current plate tectonic and magnetic anomaly theory. (MVL)

Shea, James H.

1988-01-01

291

Chemical Compositions and Anomalies in Stellar Coronae  

NASA Technical Reports Server (NTRS)

In summary, as the papers cited here and in earlier reports demonstrate, this award has enabled us to obtain a fairly good picture of the abundance anomalies in stellar coronae. The "inverse FIP" effect in very active stars has now been fleshed out as a more complex anomaly depending on FIP, whereas before it appeared only in terms of a general metal paucity, the recent solar abundance assessment of Asplund et a1 will, if correct, challenge some of the older interpretations of coronal abundance anomalies since they imply quite different relative abundances of CNO compared with Fe, Mg and Si. Further investigations have been in into the possibility of modeling some of the recent coronal abundance anomaly results in terms of Alfven wave-driven separation of neutrals and ions in the upper chromosphere. This work still remains in the seed stage, and future funding from a different program will be requested to pursue it further.

Drake, Jeremy; Oliversen, Ronald J. (Technical Monitor)

2005-01-01

292

Classifying gauge anomalies through symmetry-protected trivial orders and classifying gravitational anomalies through topological orders  

NASA Astrophysics Data System (ADS)

In this paper, we systematically study gauge anomalies in bosonic and fermionic weak-coupling gauge theories with gauge group G (which can be continuous or discrete) in d space-time dimensions. We show a very close relation between gauge anomalies for gauge group G and symmetry-protected trivial (SPT) orders (also known as symmetry-protected topological (SPT) orders) with symmetry group G in one-higher dimension. The SPT phases are classified by group cohomology class Hd+1(G,R/Z). Through a more careful consideration, we argue that the gauge anomalies are described by the elements in Free[Hd+1(G,R/Z)]?H??d+1(BG,R/Z). The well known Adler-Bell-Jackiw anomalies are classified by the free part of Hd+1(G,R/Z) (denoted as Free[Hd+1(G,R/Z)]). We refer to other kinds of gauge anomalies beyond Adler-Bell-Jackiw anomalies as non-ABJ gauge anomalies, which include Witten SU(2) global gauge anomalies. We introduce a notion of ?-cohomology group, H??d+1(BG,R/Z), for the classifying space BG, which is an Abelian group and include Tor[Hd+1(G,R/Z)] and topological cohomology group Hd+1(BG,R/Z) as subgroups. We argue that H??d+1(BG,R/Z) classifies the bosonic non-ABJ gauge anomalies and partially classifies fermionic non-ABJ anomalies. Using the same approach that shows gauge anomalies to be connected to SPT phases, we can also show that gravitational anomalies are connected to topological orders (i.e., patterns of long-range entanglement) in one-higher dimension.

Wen, Xiao-Gang

2013-08-01

293

TIME SERIES ANALYSIS OF REMOTELY-SENSED TIR EMISSION: linking anomalies to physical processes  

NASA Astrophysics Data System (ADS)

In the last 15 years, remote sensing has been evaluated for detecting thermal anomalies as precursor to earthquakes. Important issues that need yet to be tackled include definition of: (a) thermal anomaly, taking into account weather conditions, observation settings and ';natural' variability caused by background sources (b) the length of observations required for this purpose; and (c) the location of detected anomalies, which should be physically related to the tectonic activity. To determine whether thermal anomalies are statistical noise, mere meteorological conditions, or actual earthquake-related phenomena, we apply a novel approach. We use brightness temperature (top-of-atmosphere) data from thermal infrared imagery acquired at a hypertemporal (sub-hourly) interval, from geostationary weather satellites over multiple years. The length of the time series allows for analysis of meteorological effects (diurnal, seasonal or annual trends) and background variability, through the application of a combined spatial and temporal filter to distinguish extreme occurrences from trends. The definition of potential anomalies is based on statistical techniques, taking into account published (geo)physical characteristics of earthquake related thermal anomalies. We use synthetic data to test the performance of the proposed detection method and track potential factors affecting the results. Subsequently, we apply the method on original data from Iran and Turkey, in quiescent and earthquake-struck periods alike. We present our findings with main focus to assess resulting anomalies in relation to physical processes thereby considering: (a) meteorological effects, (b) the geographical, geological and environmental settings, and (c) physically realistic distances and potential physical relations with the activity of causative faults.

Pavlidou, E.; van der Meijde, M.; Hecker, C.; van der Werff, H.; Ettema, J.

2013-12-01

294

“Great Salinity Anomalies” in the North Atlantic  

Microsoft Academic Search

We revisited the “Great Salinity Anomaly” of the 1970s (GSA'70s; Dickson et al., 1988) and documented the newly identified “Great Salinity Anomaly” of the 1980s (hence termed GSA'80s), both propagated around the North Atlantic in a similar fashion. The advective mechanism, initially proposed to explain the observed sequence of low-salinity, low-temperature events during the GSA'70s, apparently holds also for the

Igor M. Belkin; Sydney Levitus; John Antonov; Svend-Aage Malmberg

1998-01-01

295

Probabilistic anomaly detection in distributed computer networks  

Microsoft Academic Search

Distributed host-based anomaly detection has not yet proven practical due to the ex- cessive computational overhead during training and detection. This paper considers an efficient algorithm for detecting resource anomalies in event streams with either Poisson or long-tailed arrival processes. A form of distributed, lazy evaluation is pre- sented, which uses a model for human-computer interaction based two-dimensional time and

Mark Burgess

2006-01-01

296

CP-violating CFT and trace anomaly  

E-print Network

It is logically possible that the trace anomaly in four dimension includes the Hirzebruch-Pontryagin density in CP violating theories. Although the term vanishes at free conformal fixed points, we realize such a possibility in the holographic renormalization group and show that it is indeed possible. The Hirzebruch-Pontryagin term in the trace anomaly may serve as a barometer to understand how much CP is violated in conformal field theories.

Yu Nakayama

2012-01-26

297

ANOMALY-BASED HYPERSPECTRAL IMAGE COMPRESSION  

Microsoft Academic Search

We propose a new lossy compression algorithm for hyperspectral images, which is based on spectral principal component analysis (PCA), followed by JPEG2000 (JP2K). The approach employs an anomaly-removal model in the compression process to preserve anomalous pixels. Results on two different hyperspectral image scenes show that the new algorithm not only provides good post-compression anomaly-detection performance but also improves rate-

Qian Du; Wei Zhu; James E. Fowler

2009-01-01

298

Anomaly-Based Hyperspectral Image Compression  

Microsoft Academic Search

We propose a new lossy compression algorithm for hyperspectral images, which is based on spectral principal component analysis (PCA), followed by JPEG2000 (JP2K). The approach employs an anomaly-removal model in the compression process to preserve anomalous pixels. Results on two different hyperspectral image scenes show that the new algorithm not only provides good post-compression anomaly-detection performance but also improves rate-distortion

Qian Du; Wei Zhu; James E. Fowler

2008-01-01

299

Congenital anomaly surveillance in England and Wales.  

PubMed

The National Congenital Anomaly System (NCAS) was set up in 1964, following the thalidomide epidemic, as a monitoring system designed to detect changes in the frequency of reporting of malformations. Its original aim was to detect anomalies reported within 7 days of birth. The NCAS is voluntary at all stages and covers all live- and stillbirths. It has two tiers; a 'passive system' receiving congenital anomaly notifications through a standard paper notification form, known as the SD56, and the congenital anomaly registers that send notifications electronically. Congenital anomalies are classified using the International Classification of Diseases codes and 10 monitoring groups. The Office for National Statistics performs a statistical analysis on a monthly, quarterly and annual basis, using the cumulative sum technique, which is the basis upon which surveillance alerts are raised within the system. The NCAS is now an open database where congenital anomalies can be notified whenever they are detected. The aim of this paper is to describe the current operation and uses of the NCAS based on guidelines for the evaluation of public health surveillance systems published by the Centers for Disease Control and Prevention. PMID:16337977

Misra, T; Dattani, N; Majeed, A

2006-03-01

300

Using Artificial Anomalies to Detect Unknown and Known Network Intrusions  

Microsoft Academic Search

Intrusion detection systems (IDSs) must be capable of detecting new and unknown attacks, or anomalies. We study the problem of building detection models for both pure anomaly detection and combined misuse and anomaly detection (i.e., detection of both known and unknown in- trusions). We propose an algorithm to generate artificial anomalies to coerce the inductive learner into discovering an accurate

Wei Fan; Matthew Miller; Salvatore J. Stolfo; Wenke Lee; Philip K. Chan

2001-01-01

301

Using artificial anomalies to detect unknown and known network intrusions  

Microsoft Academic Search

Intrusion detection systems (IDSs) must be capable of detecting new and unknown attacks, or anomalies. We study the problem of building detection models for both pure anomaly detection and combined misuse and anomaly detection (i.e., detection of both known and unknown intrusions). We show the necessity of artificial anomalies by discussing the failure to use conventional inductive learning methods to

Wei Fan; Matthew Miller; Salvatore J. Stolfo; Wenke Lee; Philip K. Chan

2004-01-01

302

Evidentiality and Suggestibility: A New Research Venue  

ERIC Educational Resources Information Center

Recent research suggests that acquisition of mental-state language may influence conceptual development. We examine this possibility by investigating the conceptual links between evidentiality in language and suggestibility. Young children are disproportionately suggestible and tend to change their reports or memories when questioned. The authors…

Aydin, Cagla; Ceci, Stephen J.

2009-01-01

303

Holomorphic Anomaly in Gauge Theory on ALE space  

E-print Network

We consider four-dimensional Omega-deformed N=2 supersymmetric SU(2) gauge theory on A1 space and its lift to five dimensions. We find that the partition functions can be reproduced via special geometry and the holomorphic anomaly equation. Schwinger type integral expressions for the boundary conditions at the monopole/dyon point in moduli space are inferred. The interpretation of the five-dimensional partition function as the partition function of a refined topological string on A1x(local P1xP1) is suggested.

Daniel Krefl; Sheng-Yu Darren Shih

2011-12-12

304

Spatial distributions of tropical cyclones and gravity anomalies  

NASA Astrophysics Data System (ADS)

Spatial distributions of the beginnings and most intense stages of tropical cyclones (TCs) in the northwestern part of the Pacific Ocean are compared with gravity anomalies (GAs) in the zone of action of cyclones. The possible influence of GAs on hurricanes that reached land in the Gulf of Mexico region and in the southeastern part of China is considered. The relation of the formal feedback between some characteristics of the intensity of TCs and spatially averaged GAs is shown. It is suggested that GAs can be regarded as a factor affecting the life cycle of a TC to a certain extent.

Yaroshevich, M. I.

2013-05-01

305

Muon g-2 Anomaly and Dark Leptonic Gauge Boson  

SciTech Connect

One of the major motivations to search for a dark gauge boson of MeV-GeV scale is the long-standing muon g-2 anomaly. Because of active searches such as fixed target experiments and rare meson decays, the muon g-2 favored parameter region has been rapidly reduced. With the most recent data, it is practically excluded now in the popular dark photon model. We overview the issue and investigate a potentially alternative model based on the gauged lepton number or U(1)_L, which is under different experimental constraints.

Lee, Hye-Sung [W& M

2014-11-01

306

Using Physical Models for Anomaly Detection in Control Systems  

NASA Astrophysics Data System (ADS)

Supervisory control and data acquisition (SCADA) systems are increasingly used to operate critical infrastructure assets. However, the inclusion of advanced information technology and communications components and elaborate control strategies in SCADA systems increase the threat surface for external and subversion-type attacks. The problems are exacerbated by site-specific properties of SCADA environments that make subversion detection impractical; and by sensor noise and feedback characteristics that degrade conventional anomaly detection systems. Moreover, potential attack mechanisms are ill-defined and may include both physical and logical aspects.

Svendsen, Nils; Wolthusen, Stephen

307

Feasibility of anomaly detection and characterization using trans-admittance mammography with 60 × 60 electrode array  

NASA Astrophysics Data System (ADS)

Electrical impedance imaging has the potential to detect an early stage of breast cancer due to higher admittivity values compared with those of normal breast tissues. The tumor size and extent of axillary lymph node involvement are important parameters to evaluate the breast cancer survival rate. Additionally, the anomaly characterization is required to distinguish a malignant tumor from a benign tumor. In order to overcome the limitation of breast cancer detection using impedance measurement probes, we developed the high density trans-admittance mammography (TAM) system with 60 × 60 electrode array and produced trans-admittance maps obtained at several frequency pairs. We applied the anomaly detection algorithm to the high density TAM system for estimating the volume and position of breast tumor. We tested four different sizes of anomaly with three different conductivity contrasts at four different depths. From multifrequency trans-admittance maps, we can readily observe the transversal position and estimate its volume and depth. Specially, the depth estimated values were obtained accurately, which were independent to the size and conductivity contrast when applying the new formula using Laplacian of trans-admittance map. The volume estimation was dependent on the conductivity contrast between anomaly and background in the breast phantom. We characterized two testing anomalies using frequency difference trans-admittance data to eliminate the dependency of anomaly position and size. We confirmed the anomaly detection and characterization algorithm with the high density TAM system on bovine breast tissue. Both results showed the feasibility of detecting the size and position of anomaly and tissue characterization for screening the breast cancer.

Zhao, Mingkang; Wi, Hun; Lee, Eun Jung; Woo, Eung Je; In Oh, Tong

2014-10-01

308

Gravity anomalies, forearc morphology and seismicity in subduction zones  

NASA Astrophysics Data System (ADS)

We apply spectral averaging techniques to isolate and remove the long-wavelength large-amplitude trench-normal topographic and free-air gravity anomaly "high" and "low" associated with subduction zones. The residual grids generated illuminate the short-wavelength structure of the forearc. Systematic analysis of all subduction boundaries on Earth has enabled a classification of these grids with particular emphasis placed on topography and gravity anomalies observed in the region above the shallow seismogenic portion of the plate interface. The isostatic compensation of these anomalies is investigated using 3D calculations of the gravitational admittance and coherence. In the shallow region of the megathrust, typically within 100 km from the trench, isolated residual anomalies with amplitudes of up to 2.5 km and 125 mGal are generally interpreted as accreted/subducting relief in the form of seamounts and other bathymetric features. While most of these anomalies, which have radii < 50km, are correlated with areas of reduced seismicity, several in regions such as Japan and Java appear to have influenced the nucleation and/or propagation of large magnitude earthquakes. Long-wavelength (500 - >1000 km) trench-parallel forearc ridges with residual anomalies of up to 1.5 km and 150 mGal are identified in approximately one-third of the subduction zones analyzed. Despite great length along strike, these ridges are less than 100 km wide and several appear uncompensated. A high proportion of arc-normal structure and the truncation/morphological transition of trench-parallel forearc ridges is explained through the identification and tracking of pre-existing structure on the over-riding and subducting plates into the seismogenic portion of the plate boundary. Spatial correlations between regions with well-defined trench-parallel forearc ridges and the occurrence of large magnitude interplate earthquakes, in addition to the uncompensated state of these ridges, suggest links between the morphology of the forearc and the peak earthquake stress drop on the subduction megathrust. We present our classification of residual bathymetric and gravitational anomalies using examples from Sumatra, Kuril-Kamchatka, Mariana, Peru-Chile and the Tonga-Kermadec margin. We reassess proposed links between trench-parallel residual topography and gravity anomalies and subduction zone seismicity using global earthquake catalogs and a new compilation of published aftershock locations and distributed slip models from over 200 of the largest subduction zone earthquakes. Our results highlight the role of pre-existing structure in both the over-riding and subducting plates in modulating the along- and across-strike segmentation of subduction zones. Understanding the genesis of long-wavelength trench-parallel forearc ridges may provide further insights into links between forearc morphology, the rheology of the overriding and subducting plates and seismicity in subduction zones.

Bassett, D.; Watts, A. B.; Das, S.

2012-12-01

309

The influence of suggestibility on memory.  

PubMed

We provide a translation of Binet and Henri's pioneering 1894 paper on the influence of suggestibility on memory. Alfred Binet (1857-1911) is famous as the author who created the IQ test that bears his name, but he is almost unknown as the psychological investigator who generated numerous original experiments and fascinating results in the study of memory. His experiments published in 1894 manipulated suggestibility in several ways to determine effects on remembering. Three particular modes of suggestion were employed to induce false recognitions: (1) indirect suggestion by a preconceived idea; (2) direct suggestion; and (3) collective suggestion. In the commentary we suggest that Binet and Henri's (1894) paper written over 115 years ago is still highly relevant even today. In particular, Binet's legacy lives on in modern research on misinformation effects in memory, in studies of conformity, and in experiments on the social contagion of memory. PMID:21144772

Nicolas, Serge; Collins, Thérèse; Gounden, Yannick; Roediger, Henry L

2011-06-01

310

A magnetic anomaly of possible economic significance in southeastern Minnesota  

USGS Publications Warehouse

An aeromagnetic survey in southeastern Minnesota by the U. S. Geological Survey in cooperation with the State of Minnesota has revealed a high-amplitude, linear, and narrow magnetic feature that suggests a possible source of Precambrian iron-formation of economic value. For the past few years the U. S. Geological Survey has been conducting detailed geophysical studies of the midcontinent gravity anomaly--a broad, high-amplitude feature that extends from Lake Superior through the States of Minnesota, Iowa, Nebraska, and part of Kansas. As part of this study an aeromagnetic survey of the southern part of the State was made in cooperation with the State of Minnesota during the summer of 1963, in which a linear high-amplitude anomaly of the order of 4,000 gammas was discovered. Because of the high amplitude, the linearity, and the narrowness of the magnetic feature, it is believed the source may be Precambrian iron-formation of possible economic value. The anomalous area is in Fillmore County, approximately between the towns of Lanesboro and Peterson in the extreme southeastern part of the State. (See figures 1 and 2.) At the site of the anomaly, Cambrian sedimentary rocks occur in the valley of the Root River, and Ordovician rocks (nearly flat lying) mantle the upland areas. The uplands are largely covered by glacial deposits, which are relatively thin (Paul K. Sims, written communication, 1964). Depths to the Precambrian are estimated to range from 500 feet to 1,000 feet below the surface. The aeromagnetic map shown in figure 2 was compiled from continuous magnetic profiles made along east-west flight lines 1,000 feet above ground, and spaced approximately 1 mile apart. Contour intervals of 20, 100, and 500 gammas were used depending on the intensity. The instrument for the survey was a flux-gate type magnetometer (AN/ASQ-3A) which measures total-field variations. The contour map displays variations in magnetic pattern which are typical of shallow Precambrian rocks. Anomalies of the order of 1,000 gammas are shown along the east and west edges of the map. The outstanding feature is the previously mentioned linear positive anomaly that trends northeast and reaches a peak of 3,960 gammas. The positive anomaly is contoured from data on four consecutive profiles, but only two show high amplitudes. The high-amplitude anomalies along traverses 1 and 2 are shown in figure 3. Depth calculations suggest that the source of the anomaly lies about 1,000 feet below the surface. Assuming a dikelike source and magnetization resulting entirely from induction in the earth's field, several calculations were made in an attempt to fit the magnetic profile taken along the line AA' (see figs. 2 and 4), considered to be a typical cross-section of the magnetic anomaly. Comparisons are shown between observed and computed profiles. The fixed parameters used were (a) distance from detector to source of 2,000 ft; width of dike of 5,000 ft; dip of dike of 75?, 90?, 105? , and 120? , as shown. The best fit occurs when the dike is vertical or dips 75? to the southwest. For these cases, the susceptibility, k, is computed to be 0.016 c.g.s, units, and is comparable to k = 0.02+ calculated by Bath (1962) for the relatively unmetamorphosed iron-formation of the Main Megabi district in Minnesota where the induced magnetization was most likely the dominant magnetization. If the dominant magnetization for the anomaly in Fillmore County were remanent rather than induced, the economic importance of the anomaly would be greatly reduced. This anomaly seems sufficiently promising to warrant further geologic and geophysical investigation. Detailed ground magnetic and electrical studies would be useful to delineate the feature. In the final analysis, however, the presence of iron-formation can be determined only by the drill.

Zietz, Isidore

1964-01-01

311

Is plagioclase removal responsible for the negative Eu anomaly in the source regions of mare basalts?  

NASA Technical Reports Server (NTRS)

The nearly ubiquitous presence of a negative Eu anomaly in the mare basalts has been suggested to indicate prior separation and flotation of plagioclase from the basalt source region during its crystallization from a lunar magma ocean (LMO). Are there any mare basalts derived from a mantle source which did not experience prior plagioclase separation? Crystal chemical rationale for REE substitution in pyroxene suggests that the combination of REE size and charge, M2 site characteristics of pyroxene, fO2, magma chemistry, and temperature may account for the negative Eu anomaly in the source region of some types of primitive, low TiO2 mare basalts. This origin for the negative Eu anomaly does not preclude the possibility of the LMO as many mare basalts still require prior plagioclase crystallization and separation and/or hybridization involving a KREEP component.

Shearer, C. K.; Papike, J. J.

1989-01-01

312

Breakup Threshold Anomaly: New Manifestation of the Dispersion Relation  

E-print Network

It is pointed out that the usual threshold anomaly, found operative in the energy behavior of the imaginary and real parts of the optical potential representing the elastic scattering of tightly bound nuclei at near- and below-barrier energies, suffers a drastic qualitative change in the case of the elastic scattering of weakly bound projectile nuclei. Owing to the strong coupling to the breakup channel even at sub-barrier energies, the imaginary potential strength seems to increase as the energy is lowered down to below the natural, barrier, threshold, accompanied by a decrease in the real potential strength. This feature is consistent with the dispersion relation. It also clearly indicates the effective increase of the barrier height. The systems $^{9}$Be,$^{16}$O + $^{64}$Zn and $^{6,7}$Li + $^{138}$Ba are analyzed to illustrate this new phenomenon.

Chamon, L C; Hussein, M S

2006-01-01

313

Geographic variation and localised clustering of congenital anomalies in Great Britain  

PubMed Central

Background Environmental pollution as a cause of congenital anomalies is sometimes suspected because of clustering of anomalies in areas of higher exposure. This highlights questions around spatial heterogeneity (clustering) in congenital anomaly rates. If spatial variation is endemic, then any one specific cluster is less remarkable, though the presence of uncontrolled geographically clustered risk factors is suggested. If rates are relatively homogeneous across space other than around specific hazards, then evidence for these hazards causing the clusters is strengthened. We sought to estimate the extent of spatial heterogeneity in congenital anomaly rates in the United Kingdom. Methods The study population covered about one million births from five registers in Britain from 1991–1999. We estimated heterogeneity across four geographical levels: register area, hospital catchment, electoral ward, and enumeration district, using a negative binomial regression model. We also sought clusters using a circular scan statistic. Results Congenital anomaly rates clearly varied across register areas and hospital catchments (p < 0.001), but not below this level (p > 0.2). Adjusting for socioeconomic deprivation and maternal age made little difference to the extent of geographical variation for most congenital anomaly subtypes. The two most significant circular clusters (of four ano-rectal atresias and six congenital heart diseases) contained two or more siblings. Conclusion The variation in rates between registers and hospital catchment area may have resulted in part from differences in case ascertainment, and this should be taken into account in geographical epidemiological studies of environmental exposures. The absence of evidence for variation below this level should be interpreted cautiously in view of the low power of general heterogeneity tests. Nevertheless, the data suggest that strong localised clusters in congenital anomalies are uncommon, so clusters around specific putative environmental hazards are remarkable when observed. Negative binomial models applied at successive hierarchical levels provide an approach of intermediate complexity to characterising geographical heterogeneity. PMID:17617898

Armstrong, Ben G; Dolk, Helen; Pattenden, Sam; Vrijheid, Martine; Loane, Maria; Rankin, Judith; Dunn, Chris E; Grundy, Chris; Abramsky, Lenore; Boyd, Patricia A; Stone, David; Wellesley, Diana

2007-01-01

314

Geological reasons for change in intensity of linear magnetic anomalies of the Kursk magnetic anomaly  

NASA Technical Reports Server (NTRS)

The geological reasons for fluctuations in the anomalous field intensity along the polar axes were examined. The Kursk magnetic anomaly is used as the basis for the study. A geological-geophysical section was constructed which used the results of the interpretation of gravimagnetic anomalies.

Zhavoronkin, I. A.; Kopayev, V. V.

1985-01-01

315

Hypnotizability, not suggestion, influences false memory development.  

PubMed

Hypnotizability influences the development of false memories. In Experiment 1, participants heard a positive or negative suggestion regarding hypnosis and then listened to 8 Deese-Roediger-McDermott (DRM) false memory paradigm lists in a hypnotic state. Neither hypnosis nor prehypnotic suggestion affected memory. Highly hypnotizable participants were more accurate in recall and recognition. In Experiment 2, suggestions were delivered in the form of feedback. Participants heard a positive or negative suggestion about their performance prior to either the encoding or retrieval of 8 DRM lists. Neither accurate nor false memories were affected by the suggestion. Highly hypnotizable individuals recognized fewer critical lures if they received a negative suggestion about their performance. These results highlight the unusual role of hypnotizability in the creation of false memories. PMID:25365130

Dasse, Michelle N; Elkins, Gary R; Weaver, Charles A

2015-01-01

316

MedMon: securing medical devices through wireless monitoring and anomaly detection.  

PubMed

Rapid advances in personal healthcare systems based on implantable and wearable medical devices promise to greatly improve the quality of diagnosis and treatment for a range of medical conditions. However, the increasing programmability and wireless connectivity of medical devices also open up opportunities for malicious attackers. Unfortunately, implantable/wearable medical devices come with extreme size and power constraints, and unique usage models, making it infeasible to simply borrow conventional security solutions such as cryptography. We propose a general framework for securing medical devices based on wireless channel monitoring and anomaly detection. Our proposal is based on a medical security monitor (MedMon) that snoops on all the radio-frequency wireless communications to/from medical devices and uses multi-layered anomaly detection to identify potentially malicious transactions. Upon detection of a malicious transaction, MedMon takes appropriate response actions, which could range from passive (notifying the user) to active (jamming the packets so that they do not reach the medical device). A key benefit of MedMon is that it is applicable to existing medical devices that are in use by patients, with no hardware or software modifications to them. Consequently, it also leads to zero power overheads on these devices. We demonstrate the feasibility of our proposal by developing a prototype implementation for an insulin delivery system using off-the-shelf components (USRP software-defined radio). We evaluate its effectiveness under several attack scenarios. Our results show that MedMon can detect virtually all naive attacks and a large fraction of more sophisticated attacks, suggesting that it is an effective approach to enhancing the security of medical devices. PMID:24473551

Zhang, Meng; Raghunathan, Anand; Jha, Niraj K

2013-12-01

317

Response of Tropical Forests to Intense Climate Variability and Rainfall Anomaly over the Last Decade  

NASA Astrophysics Data System (ADS)

During the last decade, strong precipitation anomalies resulted from increased sea surface temperature in the tropical Atlantic, have caused extensive drying trends in rainforests of western Amazonia, exerting water stress, tree mortality, biomass loss, and large-scale fire disturbance. In contrast, there have been no reports on large-scale disturbance in rainforests of west and central Africa, though being exposed to similar intensity of climate variability. Using data from Tropical Rainfall Mapping Mission (TRMM) (1999-2010), and time series of rainfall observations from meteorological stations (1971-2000), we show that both Amazonian and African rainforest experienced strong precipitation anomalies from 2005-2010. We monitored the response of forest to the climate variability by analyzing the canopy water content observed by SeaWinds Ku-band Scatterometer (QSCAT) (1999-2009) and found that more than 70 million ha of forests in western Amazonia experienced a strong water deficit during the dry season of 2005 and a closely corresponding decline in canopy backscatter that persisted until the next major drought in 2010. This decline in backscatter has been attributed to loss of canopy water content and large-scale tree mortality corroborated by ground and airborne observations. However, no strong impacts was observed on tropical forests of Africa, suggesting that the African rainforest may have more resilience to droughts. We tested this hypothesis by examining the seasonal rainfall patterns, maximum water deficit, and the surface temperature variations. Results show that there is a complex pattern of low annual rainfall, moderate seasonality, and lower surface temperature in Central Africa compared to Amazonia, indicating potentially a lower evapotranspiration circumventing strong water deficits

Saatchi, S.; Asefi, S.

2012-04-01

318

Scientific Numerology, Preference Anomalies, and Environmental Policymaking  

Microsoft Academic Search

Recently an abundance of experimental evidence has been gathered that is consonant with the notion that individual preferences\\u000a are inconsistent and unstable. These empirical results potentially undermine the theoretical foundation of welfare economics,\\u000a as the degree of preference lability claimed suggests that perhaps no optimization principles underlie even the most straightforward\\u000a of choices. Yet policymakers in the environmental arena continue

John A. List

2005-01-01

319

Gravity anomalies and crustal structure at the southeast Greenland margin  

NASA Astrophysics Data System (ADS)

Free-air gravity anomalies across the southeast Greenland margin are investigated in conjunction with a well-constrained seismic velocity model to provide a constraint on subsurface density structure. This volcanic rifted margin is characterized by the presence of ˜30-km-thick igneous crust, which correlates with a positive gravity high of ˜60 mGal. A new systematic approach is adopted for gravity modeling, which consists of (1) full error propagation from the velocity model to predicted gravity anomalies through a posteriori model covariance represented by Monte Carlo ensembles, (2) the inversion of residual gravity anomalies for density variations within geological subdomains, and (3) the joint inversion of seismic travel times and gravity anomalies. A density model derived from the velocity model, using conventional conversion laws for the continental and oceanic crust, substantially underpredicts the observed gravity by ˜70 mGal over the continental shelf. Neither errors in the velocity model nor the uncertainty of the chosen conversion laws are shown to be sufficient for such a large gravity misfit. A possible range of mantle contribution is first investigated by modeling various thermal evolution and depletion scenarios, which suggests that the maximum contribution is only ˜20 mGal, assuming constant source mantle composition throughout continental rifting and subsequent seafloor spreading. If most of the residual gravity anomaly has a crustal origin, applying a conversion law with a denser upper crust in the continent-ocean transition zone seems to be the only plausible option to resolve this difficulty. Contrasting eruption environments for the transition zone crust (subaerial) and the oceanic crust (submarine) probably result in different porosity structures, to which a velocity-density relationship is highly sensitive. The wire log and laboratory measurements of plateau basalts recovered from recent drilling legs on North Atlantic margins seem to support this explanation. An alternative explanation, which invokes a strong degree of source mantle heterogeneity, is also plausible on the basis of a recent geochemical study of the North Atlantic igneous province.

Korenaga, Jun; Holbrook, W. Steven; Detrick, Robert S.; Kelemen, Peter B.

2001-05-01

320

SEM Microanalysis of Particles: Concerns and Suggestions  

NASA Astrophysics Data System (ADS)

The scanning electron microscope (SEM) is well suited to examine and characterize small (i.e. <10 micron) particles. Particles can be imaged and sizes and shapes determined. With energy dispersive x-ray spectrometers (EDS), chemical compositions can be determined quickly. Despite the ease in acquiring x-ray spectra and chemical compositions, there are potentially major sources of error to be recognized. Problems with EDS analyses of small particles: Qualitive estimates of composition (e.g. stating that Si>Al>Ca>Fe plus O) are easy. However, to be able to have confidence that a chemical composition is accurate, several issues should be examined. (1) Particle Mass Effect: Is the accelerating voltage appropriate for the specimen size? Are all the incident electrons remaining inside the particle, and not traveling out of the sample side or bottom? (2) Particle Absorption Effect: What is the geometric relationship of the beam impact point to the x-ray detector? The x-ray intensity will vary by significant amounts for the same material if the grains are irregular and the path out of the sample in the direction of the detector is longer or shorter. (3) Particle Fluorescence Effect: This is generally a smaller error, but should be considered: for small particles, using large standards, there will be a few % less x-rays generated in a small particle relative to one of the same composition and 50-100 times larger. Also, if the sample sits on a grid of a particular composition (e.g. Si wafer) potentially several % of Si could appear in the analysis. (4) In a increasing number of laboratories, with environmental or variable pressure SEMs, the Gas Skirt Effect is operating against you: here the incident electron beam scatters in the gas in the chamber, with less electrons impacting the target spot and some others hitting grains 100s of microns away, producing spectra that could be faulty. (5) Inclusion of measured oxygen: if the measured oxygen x-ray counts are utilized, significant errors can be introduced by differential absorption of this low energy x-ray. (6) Standardless Analysis: This typical method of doing EDS analysis has a major pitfall: the printed analysis is normalized to 100 wt%, thereby eliminating an important clue to analytical error. Suggestions: (1) Use lower voltage, e.g. 10 kV, reducing effects 1,2,3 above. (2) Use standards--traditional flat polished ones--and don't initially normalize totals. Discrepancies can be observed and addressed, not ignored. (3) Alway include oxygen by stoichometry, not measured. (4) Experimental simulation. Using material of constant composition (e.g. NIST glass K-411, or other homogeneous multi-element material with the elements of interest), grind into fragments of similar size to your unknowns, and see what is the analytical error for measurements of these known particles. Analyses of your unknown material will be no better, and probably worse than that, particularly if the grains are smaller. The results of this experiment should be reported whenever discussing measurements on the unknown materials. (5) Monte Carlo simulation. Programs such PENEPMA allows creation of complex geometry samples (and samples on substrates) and resulting EDS spectra can be generated. This allows estimation of errors for representative cases. It is slow, however; other simulations such as DTSA-II promise faster simulations with some limitations. (6) EBSD: this is a perfectly suited for some problems with SEM identification of small particles, e.g. distinguishing magnetite (Fe3O4) from hematite (Fe2O3), which is virtually impossible to do by EDS. With the appropriate hardware and software, electron diffraction patterns on particles can be gathered and the crystal type determined.

Fournelle, J.

2008-12-01

321

Minor physical anomalies are more common in schizophrenia patients with the history of homicide.  

PubMed

Minor physical anomalies may be external markers of abnormal brain development, so the more common appearance of these signs in homicidal schizophrenia might suggest the possibility of a more seriously aberrant neurodevelopment in this subgroup. The aim of the present study was to investigate the rate and topological profile of minor physical anomalies in patients with schizophrenia with the history of committed or attempted homicide comparing them to patients with schizophrenia without homicide in their history and to normal control subjects. Using a list of 57 minor physical anomalies, 44 patients with the diagnosis of schizophrenia were examined with the history of committed or attempted homicide, as a comparison 22 patients with the diagnosis of schizophrenia without the history of any kind of homicide and violence and 21 normal control subjects were examined. Minor physical anomalies are more common in homicidal schizophrenia patients compared to non-homicidal schizophrenia patients and normal controls, which could support a stronger neurodevelopmental component of etiology in this subgroup of schizophrenia. The higher rate of minor physical anomalies found predominantly in the head and mouth regions in homicidal schizophrenia patients might suggest the possibility of a more seriously aberrant brain development in the case of homicidal schizophrenia. PMID:25500346

Tényi, Tamás; Halmai, Tamás; Antal, Albert; Benke, Bálint; Jeges, Sára; Tényi, Dalma; Tóth, Ákos Levente; Csábi, Györgyi

2015-02-28

322

Direct recovery of mean gravity anomalies from satellite to satellite tracking  

NASA Technical Reports Server (NTRS)

The direct recovery was investigated of mean gravity anomalies from summed range rate observations, the signal path being ground station to a geosynchronous relay satellite to a close satellite significantly perturbed by the short wave features of the earth's gravitational field. To ensure realistic observations, these were simulated with the nominal orbital elements for the relay satellite corresponding to ATS-6, and for two different close satellites (one at about 250 km height, and the other at about 900 km height) corresponding to the nominal values for GEOS-C. The earth's gravitational field was represented by a reference set of potential coefficients up to degree and order 12, considered as known values, and by residual gravity anomalies obtained by subtracting the anomalies, implied by the potential coefficients, from their terrestrial estimates. It was found that gravity anomalies could be recovered from strong signal without using any a-priori terrestrial information, i.e. considering their initial values as zero and also assigning them a zero weight matrix. While recovering them from weak signal, it was necessary to use the a-priori estimate of the standard deviation of the anomalies to form their a-priori diagonal weight matrix.

Hajela, D. P.

1974-01-01

323

New type of anomaly in turbulence.  

PubMed

The turbulent energy flux through scales, ??, remains constant and nonvanishing in the limit of zero viscosity, which results in the fundamental anomaly of time irreversibility. It was considered straightforward to deduce from this the Lagrangian velocity anomaly, ?du(2)/dt?=-4?? at t=0, where u[over ?] is the velocity difference of a pair of particles, initially separated by a fixed distance. Here we demonstrate that this assumed first taking the limit t?0 and then ??0, while a zero-friction anomaly requires taking viscosity to zero first. We find that the limits t?0 and ??0 do not commute if particles deplete (accumulate) in shocks backward (forward) in time on the viscous time scale. We compute analytically the resultant Lagrangian anomaly for one-dimensional Burgers turbulence and find it completely altered: ?du(2)/dt? has different values forward and backward in time. For incompressible flows, on the other hand, we show that the limits commute and the Lagrangian anomaly is still induced by the flux law, apparently due to a homogeneous distribution of fluid particles at all times. PMID:25062187

Frishman, Anna; Falkovich, Gregory

2014-07-11

324

New Type of Anomaly in Turbulence  

NASA Astrophysics Data System (ADS)

The turbulent energy flux through scales, ? ¯, remains constant and nonvanishing in the limit of zero viscosity, which results in the fundamental anomaly of time irreversibility. It was considered straightforward to deduce from this the Lagrangian velocity anomaly, ?du2/dt?=-4? ¯ at t =0, where u ? is the velocity difference of a pair of particles, initially separated by a fixed distance. Here we demonstrate that this assumed first taking the limit t?0 and then ??0, while a zero-friction anomaly requires taking viscosity to zero first. We find that the limits t?0 and ??0 do not commute if particles deplete (accumulate) in shocks backward (forward) in time on the viscous time scale. We compute analytically the resultant Lagrangian anomaly for one-dimensional Burgers turbulence and find it completely altered: ?du2/dt? has different values forward and backward in time. For incompressible flows, on the other hand, we show that the limits commute and the Lagrangian anomaly is still induced by the flux law, apparently due to a homogeneous distribution of fluid particles at all times.

Frishman, Anna; Falkovich, Gregory

2014-07-01

325

On Anomaly Matching and Holography  

E-print Network

We discuss the possible validity in QCD of a relation between Green's functions which has been recently suggested by Son and Yamamoto, based on a class of AdS/CFT-inspired models of QCD. Our conclusion is that the relation in question is unlikely to be implemented in QCD.

Marc Knecht; Santiago Peris; Eduardo de Rafael

2011-01-04

326

Cerebral Mechanisms of Hypnotic Induction and Suggestion  

Microsoft Academic Search

The neural mechanisms underlying hypnotic states and responses to hypnotic suggestions remain largely unknown and, to date, have been studied only with indirect methods. Here, the effects of hypnosis and suggestions to alter pain perception were investigated in hypnotizable subjects by using positron emission tomography (PET) measures of regional cerebral blood flow (rCBF) and electroencephalographic (EEG) measures of brain electrical

Pierre Rainville; Robert K. Hofbauer; Tomáš Paus; Gary H. Duncan; M. Catherine Bushnell; Donald D. Price

1999-01-01

327

Suggested Learnings: Consumer and Homemaking Education.  

ERIC Educational Resources Information Center

The guide presents suggested learning concepts, experiences, and references for home economics educators in the planning and organization of secondary level consumer and homemaking programs. The suggestions are based on questionnaires and interviews with teachers and administrators involved in this program. The guide's main focus is on the process…

Edmondson, Dorothy Jean; Swanson, Bettye B.

328

Covariation between growth and morphology suggests alternative  

E-print Network

Covariation between growth and morphology suggests alternative size limits for the blacklip abalone in width are less variable than growth in length suggests that a mini- mum legal width limit may be more minimum size limits have traditionally been estimated by considering average rates of growth, mortality

329

Resolving P-wave travel-time anomalies using seismic array observations of oceanic storms  

E-print Network

Resolving P-wave travel-time anomalies using seismic array observations of oceanic storms Jian California reveals P-wave arrivals from distant storms in open oceans. In this case, the noise can results suggest using oceanic storms as additional seismic sources for resolving P-wave travel

Gerstoft, Peter

330

A source-depth separation filter: Using the Euler method on the derivatives of total intensity magnetic anomaly data  

USGS Publications Warehouse

An overview is given on the benefits of applying the Euler method on derivatives of anomalies to enhance the location of shallow and deep sources. Used properly, the method is suitable for characterizing sources from all potential-field data and/or their derivative, as long as the data can be regarded mathematically as "continuous". Furthermore, the reasons why the use of the Euler method on derivatives of anomalies is particularly helpful in the analysis and interpretation of shallow features are explained.

Ravat, D.; Kirkham, K.; Hildenbrand, T.G.

2002-01-01

331

Holographic entanglement entropy and gravitational anomalies  

NASA Astrophysics Data System (ADS)

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 worldline into a ribbon, and that the anomalous contribution to the CFT entanglement entropy is given by the twist in this ribbon. The entanglement functional may also be interpreted as the worldline action for a spinning particle — that is, an anyon — in three-dimensional curved spacetime. We demonstrate that the minimization of this action results in the Mathisson-Papapetrou-Dixon equations of motion for a spinning particle in three dimensions. We work out several simple examples and demonstrate agreement with CFT calculations.

Castro, Alejandra; Detournay, Stephane; Iqbal, Nabil; Perlmutter, Eric

2014-07-01

332

Trace anomalies in chiral theories revisited  

NASA Astrophysics Data System (ADS)

Motivated by the search for possible CP violating terms in the trace of the energy-momentum tensor in theories coupled to gravity we revisit the problem of trace anomalies in chiral theories. We recalculate the latter and ascertain that in the trace of the energy-momentum tensor of theories with chiral fermions at one-loop the Pontryagin density appears with an imaginary coefficient. We argue that this may break unitarity, in which case the trace anomaly has to be used as a selective criterion for theories, analogous to the chiral anomalies in gauge theories. We analyze some remarkable consequences of this fact, that seem to have been overlooked in the literature.

Bonora, Loriano; Giaccari, Stefano; de Souza, Bruno Lima

2014-07-01

333

Interpretation of satellite elevation magnetic anomalies  

NASA Technical Reports Server (NTRS)

The present discussion is based on a study of the magnetic field data obtained with the aid of the magnetic field satellite Magsat, deployed in October 1979, over most of the earth during a 7.5-month mission. Inversions using spherical harmonic coefficients are considered along with the inversion of residual fields. In order to perform the correct operation, it is necessary to add on to the source function produced by the inversion process a magnetization function which has no external field. Such a function is known as an annihilator. The use of the annihilator for Pacific Ocean anomalies is discussed. Attention is given to models of oceanic crustal magnetization, and continental long-wavelength anomalies. It is found that in continental regions the annihilator is also useful if induced magnetizations are thought to be responsible for the long-wavelength anomaly.

Harrison, C. G. A.; Carle, H. M.; Hayling, K. L.

1986-01-01

334

Detecting data anomalies methods in distributed systems  

NASA Astrophysics Data System (ADS)

Distributed systems became most popular systems in big companies. Nowadays many telecommunications companies want to hold large volumes of data about all customers. Obviously, those data cannot be stored in single database because of many technical difficulties, such as data access efficiency, security reasons, etc. On the other hand there is no need to hold all data in one place, because companies already have dedicated systems to perform specific tasks. In the distributed systems there is a redundancy of data and each system holds only interesting data in appropriate form. Data updated in one system should be also updated in the rest of systems, which hold that data. There are technical problems to update those data in all systems in transactional way. This article is about data anomalies in distributed systems. Avail data anomalies detection methods are shown. Furthermore, a new initial concept of new data anomalies detection methods is described on the last section.

Mosiej, Lukasz

2009-06-01

335

The mineralogy of global magnetic anomalies  

NASA Technical Reports Server (NTRS)

Experimental and analytical data on magnetic mineralogy was provided as an aid to the interpretation of magnetic anomaly maps. An integrated program, ranging from the chemistry of materials from 100 or more km depth within the Earth, to an examination of the MAGSAT anomaly maps at about 400 km above the Earth's surface, was undertaken. Within this framework, a detailed picture of the pertinent mineralogical and magnetic relationships for the region of West Africa was provided. Efforts were directed toward: (1) examining the geochemistry, mineralogy, magnetic properties, and phases relations of magnetic oxides and metal alloys in rocks demonstrated to have originated in the lower crust of upper mantle, (2) examining the assumption that these rocks portray the nature of their source regions; and (3) examining the regional geology, tectonics, gravity field and the MAGSAT anomaly maps for West Africa.

Haggerty, S. E. (principal investigator)

1984-01-01

336

Winter-to-Winter Recurrence of Sea Surface Temperature, Salinity and Mixed Layer Depth Anomalies  

Microsoft Academic Search

The mean seasonal cycle of mixed layer depth (MLD) in the extratropical oceans has the potential to influence temperature, salinity and mixed layer depth anomalies from one winter to the next. Temperature and salinity anoma- lies that form at the surface and spread throughout the deep winter mixed layer are sequestered beneath the mixed layer when it shoals in spring

Michael A. Alexander; Mike S. Timlin; James D. Scott

2000-01-01

337

Imaging geometry, velocity, and anisotropy of the "African Anomaly"  

NASA Astrophysics Data System (ADS)

The "African Anomaly" is a prominent low velocity province in the lower mantle beneath Africa. I have determined the geometry and geographic distribution of a very low velocity province (VLVP) at the base of the "African Anomaly" near the core mantle boundary (CMB). The VLVP exhibits an "L-shaped" form stretching from the South Atlantic Ocean to the Indian Ocean, occupying an area of about 1.8 x 107 km2 at the CMB. Waveform modeling analyses with the SH hybrid method suggest that the VLVP has rapidly varying geometries and sharp borders as well as a linear gradient of shear velocity reduction from -2% (top) to -9% - -12% (bottom) relative to the Preliminary Reference Earth Model. These seismic characteristics unambiguously indicate that the VLVP is compositionally distinct, and can best be explained by partial melt driven by a compositional change, possibly produced early in the Earth's history. I have imaged the geometry and P- and S-velocity structures for the "African Anomaly" along the great arc from the East Pacific Rise to the Japan Sea. The "African Anomaly" exhibits a "cusplike" shape with both flanks tilting toward the apex beneath southern Africa, and it continuously extends about 1300 km upward into the mid-lower mantle. The average Vs reductions are about -5% in the base above the CMB and about -2% - -3% in the mid-lower portion above the base. A uniform Vs to Vp perturbation ratio of 3:1 can best explain the P wave data. The geometry and seismic features indicate that the mid-lower mantle portion of the "African Anomaly" is an integrated component of the VLVP at the base, and might also be compositionally distinct and geologically stable. After the geometry and seismic structure were imaged for the "African Anomaly", I have studied the anisotropy associated with the VLVP at the base of the "African Anomaly". I measure the apparent splitting parameters (the fast polarization direction and the delay time) for high-quality SKS and SKKS waveforms of deep earthquakes. The medium in the interior of the VLVP may be isotropic or vertically transverse isotropic due to the good station correlation of apparent splitting parameters and the consistency of apparent splitting parameters for SKS and SKKS waves of the same earthquake when seismic data sample in the interior of the VLVP. However, the medium near the borders of the VLVP has to be anisotropic in order to account for the lack of station correlation of apparent splitting parameters and the inconsistency of apparent splitting parameters for SKS and SKKS waves of the same earthquake when seismic data sample near the borders of the VLVP. The anisotropy near the borders of the VLVP can be generated by the lattice-preferred orientation of anisotropic aggregates, revealing a complex mantle flow in the surrounding areas.

Wang, Yi

338

New type of anomaly in turbulence  

E-print Network

The turbulent energy flux through scales, $\\bar{\\epsilon}$, remains constant and non vanishing in the limit of zero viscosity, which results in the fundamental anomaly of time irreversibility. It was considered straightforward to deduce from this the Lagrangian velocity anomaly, $\\left=-4 \\bar{\\epsilon}$ at $t=0$, where $\\vec{u}$ is the velocity difference of a pair of particles, initially separated by a fixed distance. In this letter we demonstrate that this derivation assumed first taking the limit $t \\to 0$ and then $\

Anna Frishman; Gregory Falkovich

2014-01-23

339

Anomaly matching for the QCD string  

E-print Network

A criterion to be satisfied by a string theory of QCD is formulated in the ultraviolet regime. It arises from the trace anomaly of the QCD stress tensor computed using instantons. It is sensitive to asymptotic freedom. It appears to be related to the trace anomaly of the QCD string. Our current understanding of noncritical strings in physical dimensions is limited, but remarkably, a formal treatment of the bosonic string yields numerical agreement both in magnitude and sign for the gauge group SU(2).

Balakrishna, B S

1993-01-01

340

Holography and Anomaly Matching for Resonances  

E-print Network

We derive a universal relation for the transverse part of triangle anomalies within a class of theories whose gravity dual is described by the Yang-Mills-Chern-Simons theory. This relation provides a set of sum rules involving the masses, decay constants and couplings between resonances, and leads to the formulas for the matrix elements of the vector and axial currents in the presence of the soft electromagnetic field. We also discuss that this relation is valid in real QCD at least approximately. This may be regarded as the anomaly matching for resonances as an analogue of that for the massless excitations in QCD.

Dam T. Son; Naoki Yamamoto

2010-10-04

341

The holomorphic anomaly for open string moduli  

NASA Astrophysics Data System (ADS)

We complete the holomorphic anomaly equations for topological strings with their dependence on open moduli. We obtain the complete system by standard path integral arguments generalizing the analysis of BCOV (Commun. Math. Phys. 165 (1994) 311) to strings with boundaries. We study both the anti-holomorphic dependence on open moduli and on closed moduli in presence of Wilson lines. By providing the compactification à la Deligne-Mumford of the moduli space of Riemann surfaces with boundaries, we show that the open holomorphic anomaly equations are structured on the (real codimension one) boundary components of this space.

Bonelli, Giulio; Tanzini, Alessandro

2007-10-01

342

Radioactive anomaly discrimination from spectral ratios  

DOEpatents

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.

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

2013-08-20

343

Barriers to Policy Change and a Suggested Path for Change  

ERIC Educational Resources Information Center

China's one-child policy has been an unprecedented policy experiment in human history. Despite its significant achievements, the policy has induced equally significant potential problems. As problems of the one-child policy have been widely noticed and suggestions for adjustments are available, the leadership transition of China in 2012 and 2013…

Jing, Yijia

2013-01-01

344

The relationship between clear sky water vapor and SST anomalies  

NASA Technical Reports Server (NTRS)

The relationship between clear sky water vapor anomalies and the SST anomalies (SSTAs) was investigated with the purpose of providing data for evaluating the clear sky greenhouse effect predicted in many global warming scenarios, by statistically analyzing anomaly data sets of SST and the water vapor anomaly data (obtained by subtracting the mean value of the six years of data for a given month from the observed values). Results show that clear sky water vapor anomalies increase in association with increases in SSTAs. The clear sky water vapor anomalies high in the troposphere were also found to increase with increasing SSTA.

Peterson, Thomas C.; Vonder Haar, Thomas H.

1992-01-01

345

SUGGESTED ANALYTIC APPROACH TO TRANSMISSION RELIABILITY MARGIN  

E-print Network

SUGGESTED ANALYTIC APPROACH TO TRANSMISSION RELIABILITY MARGIN DRAFT REPORT JUNE 22 1999 Jianfeng Zhang Ian Dobson Fernando L. Alvarado POWER SYSTEMS ENGINEERING RESEARCH CENTER Electrical & Computer Engineering Dept. University of Wisconsin, Madison WI 53706 USA Abstract Transmission Reliability Margin (TRM

346

Development program enhancement suggestions (propulsion related)  

NASA Technical Reports Server (NTRS)

The following topics are briefly addressed in this one page document: (1) potential instrumentation difficulties; (2) hazardous fluid leakage; (3) propellant loading procedures and operations; (4) pressurization systems; and (5) propellant mass uncertainty.

1991-01-01

347

Suggestions for Organizing an Extension Homemakers Club.  

E-print Network

)C l245.7 13 14ID __ 'SUGGESTIONS rr FOR ORGANIZING AN EXTENSION HOMEMAKERS CLUB LIB P.AR Y APR 20 1987 B?" h Texas Agricultural Extension Service ? The Texas A&M University System :~ Zerle L. Carpenter, Director ? College Station, Texas... Suggestions for Organizing ~ an Extension Homemakers Club June Cline* Extension Homemakers Clubs provide homemakers an opportunity for continuous informal education in a variety of areas relating to the home, family, community and country. An Extension...

Cline, June

1984-01-01

348

The Origin of the Jurassic Quiet Zone -new insights from Hawaiian Jurassic magnetic anomalies (Invited)  

NASA Astrophysics Data System (ADS)

Marine magnetic anomalies recorded in oceanic crust, have played a central role in documenting Earth's magnetic field history as compiled in the geomagnetic polarity timescale (GPTS). The oldest part of the marine record is the Jurassic Quiet Zone (JQZ) (pre-M29 chrons) which is known to be a period when field intensity was low, while reversal rate was high. The origin and character of the JQZ has been the subject of marine magnetic studies over past 20 years in the western Pacific where the oldest and arguably best preserved Jurassic magnetic anomalies create three Jurassic lineation sets (Japanese, Hawaiian, and Phoenix). The Japanese JQZ sequence was extensively investigated by an aeromagnetic and 2 deeptow magnetometer surveys, revealing (i) the presence of lineated anomalies older than M29; (ii) a GPTS record extending from M29 to M44 with a tie to ODP Hole 801C and (iii) remarkably fast reversals that decrease in intensity back in time until M38. Prior to M38 there is a low amplitude zone (LAZ) in anomalies lasting until M42, when both anomaly amplitude and a lineated character reappears around Hole 801C. Recently collected (2011) high quality seasurface marine magnetic anomaly data from the Hawaiian lineations show changes in magnetic anomaly shape and amplitude that are similar in to the Japanese lineations, suggesting that the anomalies record globally coherent geomagnetic field behavior for the Jurassic. Specifically, the strong similarity of anomaly patterns between the Japanese and Hawaiian sequences from M19 to M38 supports the remarkably dynamic geomagnetic field behavior of fast reversals and changing intensity, confirming a proposed record of the GPTS sequence for M29 to M38. While the LAZ in the Hawaiian sequence is not as clear as in the Japanese lineations, we believe we can correlate the earlier M42-M44 sequence between the two sets of lineations. The slower spreading rate in the Hawaiian lineations may contribute to this lack of resolution of the LAZ and result in a less clear recording of anomalies. We present models to investigate if this is simply a lack of spatial resolution or if there are indeed different processes active within the Hawaiian sequence such as seamount/plateau formation and crustal construction.

Tominaga, M.; Tivey, M.; Sager, W. W.

2013-12-01

349

Sulfur and Hydrogen Isotope Anomalies in Organic Compounds from the Murchison Meteorite  

NASA Technical Reports Server (NTRS)

Isotopic measurements have been made on organic sulfur and phosphorus compounds recently discovered in the Murchison meteorite. Carbon, hydrogen and sulfur measurements were performed on individual members of the organic sulfur compounds, alkyl sulfonates; and carbon and hydrogen measurements were made on bulk alkyl phosphonates. Cooper and Chang reported the first carbon isotopic measurements of Murchison organic sulfonates, providing insight into the potential synthetic mechanisms of these and, possibly, other organic species. Hydrogen isotopic measurements of the sulforiates now reveal deuterium excesses ranging from +660 to +2730 %. The deuterium enrichments indicate formation of the hydrocarbon portion of these compounds in a low temperature astrophysical environment consistent with that of dense molecular clouds. Measurements of the sulfur isotopes provide further constraints on the origin and mechanism of formation of these organic molecules. Recently, there has been growing documentation of sulfur isotopic anomalies in meteoritic material. Thiemens and Jackson have shown that some bulk ureilites possess excess S-33 and Thiemens et al. have reported excess S-33 in an oldhamite separate from the Norton County meteorite. Rees and Thode reported a large S-33 excess in an Allende acid residue, however, attempts to verify this measurements have been unsuccessful, possibly due to the heterogeneous nature of the carrier phase. With the recognition that sulfur isotopes may reflect chemistry in the protosolar nebula or the precursor molecular cloud, identification of potential carriers is of considerable interest. In the present study, the stable isotopes of sulfur were measured in methane sulfonic acid extracted from the Murchison meteorite. The isotopic composition was found to be: (delta)S-33 = 2.48 %, (delta)S-34 = 2.49 % and (delta)S-36 = 6.76 %. Based upon analysis of more than 60 meteoritic and numerous terrestrial samples, the mass fractionation lines are defined by Delta-33 = (delta)S-33 -0.50(delta)S-34 and Delta-36 = (delta)s-36 - 1.97 (delta)S-34. From these relationships Delta-33 = 1.24 % and Delta-36 = 0.89 % are observed. These anomalies, particularly the Delta-33, lie well outside the range of analytical uncertainty. They are the largest observed in any meteoritic component and the first found in an organosulfur compound. As discussed by Thiemens and Jackson, due to it's position on the periodic chart, sulfur undergoes chemically induced mass independent isotopic fractionations as does oxygen. Experiments by Mauersberger et. al. show that in such processes, the magnitude of fractionation for the different isotopically substituted species varies with mass and angular momentum; thus, anomalies are expected for both S-33 and S-36, but not necessarily of the same magnitude. Laboratory experiments have also confirmed that chemically produced, mass independent fractionations are mediated by molecular symmetry factors. A chemical source of fractionation requires that the sulfur isotopic anomaly was established in the gas phase, probably in reactions involving symmetric CS2. The discovery of an anomalous sulfur isotopic composition in a specific molecule containing excess deuterium is an important advance in the understanding of the cosmochemistry of sulfur. This evidence suggests that methanesulfonic acid was synthesized by interstellar processes. Further measurements and details of possible synthesis and fractionation mechanisms will be presented.

Cooper, G. W.; Thiemens, M. H.; Jackson, T.; Chang, Sherwood

1996-01-01

350

Contribution of oceanic gabbros to sea-floor spreading magnetic anomalies.  

PubMed

The contribution of oceanic gabbros, representative rocks for layer 3 of the oceanic crust, to sea-floor spreading magnetic anomalies has been controversial because of the large variation in magnetic properties. Ocean Drilling Program (ODP) Leg 118 contains a continuous 500.7-meter section of oceanic gabbro that allows the relations between magnetization and petrologic characteristics, such as the degree of metamorphism and the magmatic evolution, to be clarified. The data suggest that oceanic gabbros, together with the effects of metamorphism and of magmatic evolution, account for a significant part of the marine magnetic anomalies. PMID:17777035

Kikawa, E; Ozawa, K

1992-10-30

351

Anomalies in the Surface-Phonon Dispersion of TiN(001)  

NASA Astrophysics Data System (ADS)

The TiN(001) surface phonons are studied by the Green's-function method. The electron-phonon interaction is described by the coupling of the electronic charge-density deformations to the nuclear displacements. Anomalies in the surface dispersion curves are found at half the distance to the boundary of the Brillouin zone in the [100] direction. The calculated surface density of states is in good agreement with that measured by Rieder and Drexel. It is suggested that the investigation of surface-phonon anomalies permits us to check the validity of bulk dynamical models.

Benedek, G.; Miura, M.; Kress, W.; Bilz, H.

1984-05-01

352

Two girls with short stature, short neck, vertebral anomalies, Sprengel deformity and intellectual disability.  

PubMed

Here, we report two unrelated girls with prenatal onset short stature, short neck, cervical vertebral anomalies, Sprengel deformity, and mild intellectual disability. The association of these features first suggested a syndromic form of Klippel-Feil anomaly. We therefore analyzed the three known disease causing genes and the candidate gene PAX1. However, direct sequencing of GDF6, GDF3, PAX1, and MEOX1 failed to identify any mutation. To our knowledge, the phenotype we report has not been described previously, leading us to speculate that this condition may represent a new syndrome. PMID:25463316

Isidor, Bertrand; David, Albert

2015-01-01

353

Seismic imaging of transition zone discontinuities suggests hot mantle west of Hawaii.  

PubMed

The Hawaiian hotspot is often attributed to hot material rising from depth in the mantle, but efforts to detect a thermal plume seismically have been inconclusive. To investigate pertinent thermal anomalies, we imaged with inverse scattering of SS waves the depths to seismic discontinuities below the Central Pacific, which we explain with olivine and garnet transitions in a pyrolitic mantle. The presence of an 800- to 2000-kilometer-wide thermal anomaly (?T(max) ~300 to 400 kelvin) deep in the transition zone west of Hawaii suggests that hot material does not rise from the lower mantle through a narrow vertical plume but accumulates near the base of the transition zone before being entrained in flow toward Hawaii and, perhaps, other islands. This implies that geochemical trends in Hawaiian lavas cannot constrain lower mantle domains directly. PMID:21617072

Cao, Q; van der Hilst, R D; de Hoop, M V; Shim, S-H

2011-05-27

354

Weak extremely-low-frequency magnetic field-induced regeneration anomalies in the planarian, Dugesia tigrina  

SciTech Connect

The authors recently reported that cephalic regeneration in the planarian Dugesia tigrina was significantly delayed in populations exposed continuously to combined parallel DC and AC magnetic fields. This effect was consistent with hypotheses suggesting an underlying resonance phenomenon. The authors report here, in a parallel series of investigations on the same model system, that the incidence of regeneration anomalies presenting as tumor-like protuberances also increases significantly (P < .001) in association with exposure to weak 60 Hz magnetic fields, with peak intensities ranging between 1.0 and 80.0 {micro}T. These anomalies often culminate in the complete disaggregation of the organism. Similar to regeneration rate effects, the incidence of regeneration anomalies is specifically dependent upon the planaria possessing a fixed orientation with respect to the applied magnetic field vectors. However, unlike the regeneration rate effects, the AC magnetic field alone, in the absence of any measurable DC field, is capable of producing these anomalies. Moreover, the incidence of regeneration anomalies follows a clear dose-response relationship as a function of AC magnetic field intensity, with the threshold for induced electric field intensity estimated at 5 {micro} V/m. The addition of either 51.1 or 78.4 {micro}T DC magnetic fields, applied in parallel combination with the AC field, enhances the appearance of anomalies relative to the 60 Hz AC field alone, but only at certain AC field intensities. Thus, whereas the previous study of regeneration rate effects appeared to involve exclusively resonance interactions, the regeneration anomalies reported here appear to result primarily from Faraday induction coupling.

Jenrow, K.A.; Smith, C.H.; Liboff, A.R. [Oakland Univ., Rochester, MI (United States). Dept. of Physics] [Oakland Univ., Rochester, MI (United States). Dept. of Physics

1996-12-31

355

NEUTRON-RICH CHROMIUM ISOTOPE ANOMALIES IN SUPERNOVA NANOPARTICLES  

SciTech Connect

Neutron-rich isotopes with masses near that of iron are produced in Type Ia and II supernovae (SNeIa and SNeII). Traces of such nucleosynthesis are found in primitive meteorites in the form of variations in the isotopic abundance of {sup 54}Cr, the most neutron-rich stable isotope of chromium. The hosts of these isotopic anomalies must be presolar grains that condensed in the outflows of SNe, offering the opportunity to study the nucleosynthesis of iron-peak nuclei in ways that complement spectroscopic observations and can inform models of stellar evolution. However, despite almost two decades of extensive search, the carrier of {sup 54}Cr anomalies is still unknown, presumably because it is fine grained and is chemically labile. Here, we identify in the primitive meteorite Orgueil the carrier of {sup 54}Cr anomalies as nanoparticles (<100 nm), most likely spinels that show large enrichments in {sup 54}Cr relative to solar composition ({sup 54}Cr/{sup 52}Cr ratio >3.6 x solar). Such large enrichments in {sup 54}Cr can only be produced in SNe. The mineralogy of the grains supports condensation in the O/Ne-O/C zones of an SNII, although a Type Ia origin cannot be excluded. We suggest that planetary materials incorporated different amounts of these nanoparticles, possibly due to late injection by a nearby SN that also delivered {sup 26}Al and {sup 60}Fe to the solar system. This idea explains why the relative abundance of {sup 54}Cr and other neutron-rich isotopes vary between planets and meteorites. We anticipate that future isotopic studies of the grains identified here will shed new light on the birth of the solar system and the conditions in SNe.

Dauphas, N. [Origins Laboratory, Department of the Geophysical Sciences and Enrico Fermi Institute, University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637 (United States); Remusat, L.; Papanastassiou, D. A.; Guan, Y.; Ma, C.; Eiler, J. M. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Chen, J. H. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Roskosz, M.; Stodolna, J., E-mail: dauphas@uchicago.ed [Unite Materiaux et Transformations, Universite de Lille 1, CNRS UMR 8207, 59655 Villeneuve d'Ascq (France)

2010-09-10

356

Reliable prediction of micro-anomalies from macro-observables  

NASA Astrophysics Data System (ADS)

A stochastic multi-scale based approach is presented in this work to detect signatures of micro-anomalies from macrolevel response variables. By micro-anomalies, we primarily refer to micro-cracks of size 10-100 ?m (depending on the material), while macro-level response variables imply, e.g., strains, strain energy density of macro-level structures (typical size often varying in the order of 10-100 m). The micro-anomalies referred above are not discernible to the naked eyes. Nevertheless, they can cause catastrophic failures of structural systems due to fatigue cyclic loading that results in initiation of fatigue cracks. Analysis of such precursory state of internal damage evolution, before amacro-crack visibly appears (say, size of a few cms), is beyond the scope of the conventional crack propagation analysis, e.g., classical fracture mechanics. The present work addresses this issue in a certain sense by incorporating the effects of micro-cracks into the macro-scale constitutive material properties (e.g., constitutive elasticity tensors) within a probabilistic formalism based on random matrix theory, maximum entropy principle, and principles of minimum complementary energy and minimum potential energy. Distinct differences are observed in the macro-level response characteristics depending on the presence or absence of micro-cracks. This particular feature can now be used to reliably detect micro-cracks from experimental measurements of macro-observables. The present work, therefore, further proposes an efficient and robust optimization scheme: (1) to identify locations of micro-cracks in macroscopic structural systems, say, in an aircraft wing which is of the size of 10- 100 m, and (2) to determine the weakened (due to the presence of micro-cracks) macroscopic material properties which will be useful in predicting the remaining useful life of structural systems. The proposed optimization scheme achieves better convergence rate and accuracy by exploiting positive-definite structure of the macroscopic constitutive matrices.

Das, Sonjoy; Chakravarty, Sourish

2014-03-01

357

Threshold anomaly for the 7Be +58Ni system at near-Coulomb-barrier energies  

NASA Astrophysics Data System (ADS)

By using recent fusion cross section measurements for the weakly bound system 7Be+58Ni around the Coulomb barrier, a simultaneous ?2 analysis of elastic scattering and fusion cross section data is performed. The analysis is carried out with optical polarization potentials for the fusion and direct reaction processes. That is, the nuclear polarization potential UN is split into a volume part UF which accounts for fusion reactions and a surface part UD R that is responsible for direct reactions. The parameters of fusion and direct reaction Woods-Saxon polarization potentials are determined by the analysis of the data. The presence of the threshold anomaly is investigated from the energy dependence of these polarization potentials. It is found that, contrary to other weakly bound systems, the 7Be+58Ni reaction presents the usual threshold anomaly.

Gómez Camacho, A.; Aguilera, E. F.

2014-12-01

358

Imaging the Formation of High-Energy Dispersion Anomalies in the Actinide UCoGa5  

NASA Astrophysics Data System (ADS)

We use angle-resolved photoemission spectroscopy to image the emergence of substantial dispersion and spectral-weight anomalies in the electronic renormalization of the actinide compound UCoGa5 that was presumed to belong to a conventional Fermi-liquid family. Kinks or abrupt breaks in the slope of the quasiparticle dispersion are detected both at low (approximately 130 meV) and high (approximately 1 eV) binding energies below the Fermi energy, ruling out any significant contribution of phonons. We perform numerical calculations to demonstrate that the anomalies are adequately described by coupling between itinerant fermions and spin fluctuations arising from the particle-hole continuum of the spin-orbit-split 5f states of uranium. These anomalies resemble the “waterfall” phenomenon of the high-temperature copper-oxide superconductors, suggesting that spin fluctuations are a generic route toward multiform electronic phases in correlated materials as different as high-temperature superconductors and actinides.

Das, Tanmoy; Durakiewicz, Tomasz; Zhu, Jian-Xin; Joyce, John J.; Sarrao, John L.; Graf, Matthias J.

2012-10-01

359

Observations of magnetic anomaly signatures in Mars Express ASPERA-3 ELS data  

NASA Astrophysics Data System (ADS)

Mars Express (MEX) Analyser of Space Plasmas and Energetic Atoms (ASPERA-3) data is providing insights into atmospheric loss on Mars via the solar wind interaction. This process is influenced by both the interplanetary magnetic field (IMF) in the solar wind and by the magnetic 'anomaly' regions of the martian crust. We analyse observations from the ASPERA-3 Electron Spectrometer near to such crustal anomalies. We find that the electrons near remanent magnetic fields either increase in flux to form intensified signatures or significantly reduce in flux to form plasma voids. We suggest that cusps intervening neighbouring magnetic anomalies may provide a location for enhanced escape of planetary plasma. Initial statistical analysis shows that intensified signatures are mainly a dayside phenomenon whereas voids are a feature of the night hemisphere.

Soobiah, Y.; Coates, A. J.; Linder, D. R.; Kataria, D. O.; Winningham, J. D.; Frahm, R. A.; Sharber, J. R.; Scherrer, J. R.; Barabash, S.; Lundin, R.; Holmström, M.; Andersson, H.; Yamauchi, M.; Grigoriev, A.; Kallio, E.; Koskinen, H.; Säles, T.; Riihelä, P.; Schmidt, W.; Kozyra, J.; Luhmann, J.; Roelof, E.; Williams, D.; Livi, S.; Curtis, C. C.; Hsieh, K. C.; Sandel, B. R.; Grande, M.; Carter, M.; Sauvaud, J.-A.; Fedorov, A.; Thocaven, J.-J.; McKenna-Lawler, S.; Orsini, S.; Cerulli-Irelli, R.; Maggi, M.; Wurz, P.; Bochsler, P.; Krupp, N.; Woch, J.; Fränz, M.; Asamura, K.; Dierker, C.

2006-06-01

360

Gravity anomalies, caldera structure, and subsurface geology in the Rotorua area, New Zealand  

SciTech Connect

This paper discusses a re-examination of gravity which indicates that Rotorua Caldera does not have the circular, negative gravity anomaly typical of other rhyolitic calderas. New gravity measurements and residual gravity anomalies in Rotorua City are consistent with numerous rhyolite domes and ignimbrite sheets, interbedded with a thick sequence of poorly-compacted sediments. Within the city a gravity high extends from the shore of Lake Rotorua south to Whakarewarewa and is associated with a buried ridge, formed by the coalescing of two rhyolite domes. A gravity low centered near Linton Park suggests that rhyolites are thin or absent in this area and sediments extend to a depth of about 1 km. A quantitative analysis of the residual gravity anomalies was limited by insufficient information about the density, extent, and thickness of the material underlying the rhyolites, and the uncertainty in the distribution and density of silicification within the sediments.

Hunt, T.M. (DSIR Geology and Geophysics, Geothermal Research Center, Private Bag 2000, Taupo (NZ))

1992-04-01

361

The satellite magnetic anomaly of Ahaggar - Evidence for African Plate motion  

NASA Technical Reports Server (NTRS)

The Ahaggar volcanic province of North Central Africa is considered a region of excess heat flow (hot spot) and hence elevated Curie isotherm. Using a modified version of the Parker FFT potential field representation, magnetic signals were calculated at Magsat altitudes for models in which the African Plate is both fixed and moving. The moving-plate model extends the Curie isotherm anomaly in the direction of plate motion and provides a satisfactory match to vertical component anomaly data when the magnitude of plate velocity is 0.75 cm/yr. Although the signal levels are marginal for the scalar component anomalies of this region, the same model provides an adequate match to this data set and is clearly preferable to a fixed-plate model.

Phillips, R. J.; Brown, C. R.

1985-01-01

362

Bilateral optic nerve aplasia: a rare isolated central nervous system anomaly.  

PubMed

Optic nerve (ON) aplasia is a rare developmental anomaly comprising of absence of the ON, ganglion cells and the central retinal vessels. It is usually accompanied by a variety of central nervous system (CNS) malformations. We report an extremely rare case of bilateral true ON aplasia occurring as an isolated CNS anomaly. A 10-month-old female child was detected with bilateral absence of fixation, associated with multiple ocular findings of microcornea, anterior embryotoxon, pupillary corectopia, partial aniridia and lens coloboma. The optic disc locations were visible as avascular whitish areas. There were no retinal vessels seen in the disc area or elsewhere. There were bilateral multiple chorioretinal atrophic patches present. B-scan ultrasonography showed bilateral absence of ONs. Magnetic resonance imaging showed thinned out bilateral ONs with a hypoplastic optic chiasma and optic tract. There were no other CNS anomalies. Flash visually evoked potential was unrecordable. PMID:25100913

Khandgave, Tejaswini P; Kulkarni, Varsha N; Muzumdar, Deepa V; Puthran, Neelam

2014-01-01

363

Enhancing business intelligence by means of suggestive reviews.  

PubMed

Appropriate identification and classification of online reviews to satisfy the needs of current and potential users pose a critical challenge for the business environment. This paper focuses on a specific kind of reviews: the suggestive type. Suggestions have a significant influence on both consumers' choices and designers' understanding and, hence, they are key for tasks such as brand positioning and social media marketing. The proposed approach consists of three main steps: (1) classify comparative and suggestive sentences; (2) categorize suggestive sentences into different types, either explicit or implicit locutions; (3) perform sentiment analysis on the classified reviews. A range of supervised machine learning approaches and feature sets are evaluated to tackle the problem of suggestive opinion mining. Experimental results for all three tasks are obtained on a dataset of mobile phone reviews and demonstrate that extending a bag-of-words representation with suggestive and comparative patterns is ideal for distinguishing suggestive sentences. In particular, it is observed that classifying suggestive sentences into implicit and explicit locutions works best when using a mixed sequential rule feature representation. Sentiment analysis achieves maximum performance when employing additional preprocessing in the form of negation handling and target masking, combined with sentiment lexicons. PMID:25054188

Qazi, Atika; Raj, Ram Gopal; Tahir, Muhammad; Cambria, Erik; Syed, Karim Bux Shah

2014-01-01

364

Enhancing Business Intelligence by Means of Suggestive Reviews  

PubMed Central

Appropriate identification and classification of online reviews to satisfy the needs of current and potential users pose a critical challenge for the business environment. This paper focuses on a specific kind of reviews: the suggestive type. Suggestions have a significant influence on both consumers' choices and designers' understanding and, hence, they are key for tasks such as brand positioning and social media marketing. The proposed approach consists of three main steps: (1) classify comparative and suggestive sentences; (2) categorize suggestive sentences into different types, either explicit or implicit locutions; (3) perform sentiment analysis on the classified reviews. A range of supervised machine learning approaches and feature sets are evaluated to tackle the problem of suggestive opinion mining. Experimental results for all three tasks are obtained on a dataset of mobile phone reviews and demonstrate that extending a bag-of-words representation with suggestive and comparative patterns is ideal for distinguishing suggestive sentences. In particular, it is observed that classifying suggestive sentences into implicit and explicit locutions works best when using a mixed sequential rule feature representation. Sentiment analysis achieves maximum performance when employing additional preprocessing in the form of negation handling and target masking, combined with sentiment lexicons. PMID:25054188

Qazi, Atika

2014-01-01

365

Kohn anomaly in phonon driven superconductors  

NASA Astrophysics Data System (ADS)

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.

Das, M. P.; Chaudhury, R.

2014-08-01

366

Ebstein's anomaly: repair based on functional analysis  

Microsoft Academic Search

Objective: ‘Classical’ repair of Ebstein's anomaly is usually performed with transverse plication of the atrialized chamber. However, the anterior leaflet has restricted motion which is an important factor of the tricuspid valve insufficiency. We studied the long term results of mobilization of the anterior leaflet associated with longitudinal plication of the right ventricule. Methods: From 1980 to July 2002, 191

S Chauvaud; A Berrebi; N d'Attellis; E Mousseaux; A Hernigou; A Carpentier

2003-01-01

367

Anomalies, U(1)' and the MSSM  

Microsoft Academic Search

This Thesis reviews an extension of the MSSM by the addition of an anomalous abelian vector multiplet and contains some original results concerning the phenomenology of an anomalous $Z'$. The review part covers an introduction of the MSSM focusing on its main features, a discussion on the chiral anomalies and how to cancel them in the Standard Model and by

Antonio Racioppi

2009-01-01

368

Dorsal Forebrain Anomaly in Williams Syndrome  

E-print Network

in range to that seen in Down syndrome, show an unusual and uneven neuropsychological profileDorsal Forebrain Anomaly in Williams Syndrome Albert M. Galaburda, MD; J. Eric Schmitt, BS; Scott W. Atlas, MD; Stephan Eliez, MD; Ursula Bellugi, EdD; Allan L. Reiss, MD Background: Williams syndrome (WMS

369

Timing Anomalies in Dynamically Scheduled Microprocessors  

Microsoft Academic Search

Previous timing analysis methods have assumed that the worst-case instruction execution time necessarily cor- responds to the worst-case behavior. We show that this assumption is wrong in dynamically scheduled processors. A cache miss, for example, can in some cases result in a shorter execution time than a cache hit. Many examples of such timing anomalies are provided. We first provide

Thomas Lundqvist; Per Stenström

1999-01-01

370

Locally covariant chiral fermions and anomalies  

NASA Astrophysics Data System (ADS)

We define chiral fermions in the presence of non-trivial gravitational and gauge background fields in the framework of locally covariant field theory. This allows to straightforwardly compute the chiral anomalies on non-compact Lorentzian spacetimes, without recourse to a weak field approximation.

Zahn, Jochen

2015-01-01

371

IPrognosis of Aircraft Anomalies 2010 Phase II  

E-print Network

Technical Abstract A Probabilistic Fatigue Damage Assessment Network (PFDAN) toolkit for Abaqus. It is based on a high fidelity Fatigue Damage Assessment Network (FDAN) which includes 1) a coupled continuumSBIR 30 31 IPrognosis of Aircraft Anomalies 2010 Phase II Proposal A1.12-8884 Probabilistic

372

Gravity anomaly detection: Apollo/Soyuz  

NASA Technical Reports Server (NTRS)

The Goddard Apollo-Soyuz Geodynamics Experiment is described. It was performed to demonstrate the feasibility of tracking and recovering high frequency components of the earth's gravity field by utilizing a synchronous orbiting tracking station such as ATS-6. Gravity anomalies of 5 MGLS or larger having wavelengths of 300 to 1000 kilometers on the earth's surface are important for geologic studies of the upper layers of the earth's crust. Short wavelength Earth's gravity anomalies were detected from space. Two prime areas of data collection were selected for the experiment: (1) the center of the African continent and (2) the Indian Ocean Depression centered at 5% north latitude and 75% east longitude. Preliminary results show that the detectability objective of the experiment was met in both areas as well as at several additional anomalous areas around the globe. Gravity anomalies of the Karakoram and Himalayan mountain ranges, ocean trenches, as well as the Diamantina Depth, can be seen. Maps outlining the anomalies discovered are shown.

Vonbun, F. O.; Kahn, W. D.; Bryan, J. W.; Schmid, P. E.; Wells, W. T.; Conrad, D. T.

1976-01-01

373

Konishi anomalies and curves without adjoints  

Microsoft Academic Search

Generalized Konishi anomaly relations in the chiral ring of N=1 supersymmetric gauge theories with unitary gauge group and chiral matter field in two-index tensor representations are derived. Contrary to previous investigations of related models we do not include matter multiplets in the adjoint representation. The corresponding curves turn out to be hyperelliptic. We also point out equivalences to models with

Karl Landsteiner

2004-01-01

374

The mineralogy of global magnetic anomalies  

NASA Technical Reports Server (NTRS)

The Curie Balance was brought to operational stage and is producing data of a preliminary nature. Substantial problems experienced in the assembly and initial operation of the instrument were, for the most part, rectified, but certain problems still exist. Relationships between the geology and the gravity and MAGSAT anomalies of West Africa are reexamined in the context of a partial reconstruction of Gondwanaland.

Haggerty, S. E. (principal investigator)

1982-01-01

375

Racialised relations in Liverpool: A contemporary anomaly  

Microsoft Academic Search

The city of Liverpool stands out as an anomaly in the mapping of ‘racialised relations’ and the black experience in England. While it shares a number of continuities with other cities, it reveals several structural and cultural features which are absent or significantly at variance with patterns elsewhere. These include extreme residential segregation, a powerful white local sentiment and insular

Stephen Small

1991-01-01

376

Satellite Anomalies from Galactic Cosmic Rays  

Microsoft Academic Search

Anomalies in communication satellite operation have been caused by the unexpected triggering of digital circuits. Interactions with galactic cosmic rays were investigated as a mechanism for a number of these events. The mechanism assumed was the charging of the base-emitter capacitance of sensitive transistors to the turn-on voltage. The calculation of the cosmic ray event rate required the determination of

D. Binder; E. C. Smith; A. B. Holman

1975-01-01

377

Hyperspectral imagery: Clutter adaptation in anomaly detection  

Microsoft Academic Search

Hyperspectral sensors are passive sensors that simultaneously record images for hundreds of contiguous and narrowly spaced regions of the electromagnetic spectrum. Each image corresponds to the same ground scene, thus creating a cube of images that contain both spatial and spectral information about the objects and backgrounds in the scene. In this paper, we present an adaptive anomaly detector designed

Susan M. Schweizer; José M. F. Moura

2000-01-01

378

Ocean response to surface heat anomalies  

SciTech Connect

An ocean general circulation model (OGCM) is used to study the response of ocean heat and mass transport to positive and negative heat flux anomalies at the ocean surface. As expected, tropical and low-latitude mixed layers respond rapidly (e-folding time about 50-70 years) to external forcing, while the response of the high-latitude mixed layer, especially the Southern Ocean and northern North Atlantic, is very slow (e-folding time greater than 300 yr). The overall response is faster for negative than positive heat flux anomaly at the surface. The meridional heat transport changes by 15% in the first 50 yr in the southern high latitudes. Surprisingly, for the next 400-500 yr the change is very small. The analysis shows that the meridional mass transport intensifies in response to a negative surface heat flux anomaly but weakens in response to a positive heat flux anomaly. For example, at model year 100 the North Atlantic Deep Water (NADW) is reduced from about 18 Sv to about 10 Sv for the positive heat flux experiment but increased to about 26 Sv for the negative heat flux experiment.

Jiang, Xingjian; Fung, Inez (NASA. Goddard Inst. for Space Studies, New York, NY (United States))

1994-05-01

379

Ocean response to surface heat anomalies  

NASA Technical Reports Server (NTRS)

An ocean general circulation model (OGCM) is used to study the response of ocean heat and mass transport to positive and negative heat flux anomalies at the ocean surface. As expected, tropical and low-latitude mixed layers respond rapidly (e-folding time about 50-70 years) to external forcing, while the response of the high-latitude mixed layer, especially the Southern Ocean and northern North Atlantic, is very slow (e-folding time greater than 300 yr). The overall response is faster for negative than positive heat flux anomaly at the surface. The meridional heat transport changes by 15% in the first 50 yr in the southern high latitudes. Surprisingly, for the next 400-500 yr the change is very small. The analysis shows that the meridional mass transport intensifies in response to a negative surface heat flux anomaly but weakens in response to a positive heat flux anomaly. For example, at model year 100 the North Atlantic Deep Water (NADW) is reduced from about 18 Sv to about 10 Sv for the positive heat flux experiment but increased to about 26 Sv for the negative heat flux experiment.

Jiang, Xingjian; Fung, Inez

1994-01-01

380

The anomaly data base of screwworm information  

NASA Technical Reports Server (NTRS)

Standard statistical processing of anomaly data in the screwworm eradication data system is possible from data compiled on magnetic tapes with the Univac 1108 computer. The format and organization of the data in the data base, which is also available on dedicated disc storage, are described.

Giddings, L. E.

1976-01-01

381

Psychoeducational Implications of Sex Chromosome Anomalies  

ERIC Educational Resources Information Center

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…

Wodrich, David L.; Tarbox, Jennifer

2008-01-01

382

Interacting topological phases and quantum anomalies  

NASA Astrophysics Data System (ADS)

Since the quantum Hall effect, the notion of topological phases of matter has been extended to those that are well-defined (or: ``protected'') in the presence of a certain set of symmetries, and that exist in dimensions higher than two. In the (fractional) quantum Hall effects (and in ``chiral'' topological phases in general), Laughlin's thought experiment provides a key insight into their topological characterization; it shows a close connection between topological phases and quantum anomalies. Compared to genuine topological phases, symmetry protected topological phases are more fragile and less entangled states of matter, and hence for their characterization we need to sharpen our understanding on how topological properties of the systems manifest themselves in the form of a quantum anomaly. By taking various kinds of symmetry protected topological phases as an example, I will demonstrate that quantum anomalies serve as a useful tool to diagnose (and even define) topological properties of the systems. I will also discuss quantum anomalies play an essential role when developing descriptions of these topological phases in terms bulk and boundary (effective) theories.

Ryu, Shinsei

2013-03-01

383

High-altitude structure of the magnetic anomalies using the gradient measurements in stratosphere  

NASA Astrophysics Data System (ADS)

HIGH-ALTITUDE STRUCTURE OF THE MAGNETIC ANOMALIES USING THE GRADIENT MEASUREMENTS IN STRATOSPHERE Yu. Tsvetkov, N. ROTANOVA, M. Belikova Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation RAS, Troitsk, Moscow Region, 142190, Russia rotanova@izmiran.rssi.ru/FAX: +7-095-3340124 Method of the recalculation of the anomaly magnetic field over the range of the altitudes of 20-40 km is suggested. Technique is based on the experimental data of the anomaly magnetic field, its vertical gradient and the gradient increment along vertical line, obtained from the aerostat gradient magnetic surveys in stratosphere. The high-altitude structure of the magnetic anomalies, obtained for the Baikal region has been constructed. These results were used to obtain the estimations of the deep magnetic sources. The numerous values of the low boundary of the sources are 30-35 km. These estimations of the depth coincide with the ones, obtained from the results of the spectral analysis of the same magnetic anomalies.

Tsvetkov, Yu.; Rotanova, N.; Belikova, M.

2003-04-01

384

Influence of Martian crustal magnetic anomalies on the emission of energetic neutral hydrogen atoms  

NASA Astrophysics Data System (ADS)

We analyze the data on hydrogen energetic neutral atoms (ENAs) emissions from the dayside of Mars, recorded by a Neutral Particle Detector of the Analyzer of Space Plasmas and Energetic Atoms aboard Mars Express from 14 March to 9 July 2004. We first identify and analyze events of the ENA flux enhancement coinciding with the presence of the crustal magnetic anomalies on the dayside of Mars. We then backtrace the ENA emissions to the lower altitudes (source region) and build up an average map of the flux intensities in the geographic coordinates with all the available data. The map shows a peak-to-valley ENA flux enhancement of 40%-90% close to the crustal magnetic anomaly regions. These results suggest the influence of the magnetic anomalies on the ENA emission from the dayside of Mars. The enhancement may result from the deviation of the highly directional plasma flow above anomalies toward the detectors such that more charge exchange ENAs would be recorded. Alternatively, higher exospheric densities above the anomalies would also result in an increase of the charge exchange ENA flux.

Wang, X.-D.; Barabash, S.; Futaana, Y.; Grigoriev, A.; Wurz, P.

2014-10-01

385

Rehabilitation of a child with partial unilateral cryptophthalmos and multiple congenital anomalies.  

PubMed Central

PURPOSE: This paper describes the surgical rehabilitation of a child with craniofacial anomalies, unilateral syndactyly, and partial unilateral cryptophthalmos associated with inferior colobomata of the iris and optic nerve and agenesis of the inferior rectus and inferior oblique muscles. The clinical presentation of cryptophthalmos is described. METHODS: The medical literature since the original description of cryptophthalmos in 1872 was reviewed to define patterns of inheritance and the incidence of associated anomalies. RESULTS: Including this patient, 149 case reports of cryptophthalmos were identified. In two families transmission from parent to child suggests dominant inheritance. None of the five dominant cases had any other anomalies, and all had bilateral complete cryptophthalmos. The incidence of cryptophthalmos in the remaining families is consistent with autosomal recessive inheritance. This group includes patients with bilateral, unilateral, and partial cryptophthalmos. Other anomalies are common, including those of the ear and nose, limbs, genitourinary system, and mouth and palate. Mortality in the perinatal period is associated with renal agenesis, laryngeal atresia, and pulmonary hypoplasia. CONCLUSIONS: Cryptophthalmos is a rare congenital anomaly with two patterns of inheritance. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 FIGURE 12 FIGURE 13 PMID:8719680

Konrad, H; Merriam, J C; Jones, I S

1995-01-01

386

Non-stationarity of the signal and noise characteristics of seasonal precipitation anomalies  

Microsoft Academic Search

In order to improve seasonal-to-interannual precipitation forecasts and their application by decision makers, there is a clear\\u000a need to understand when, where, and to what extent seasonal precipitation anomalies are driven by potentially predictable\\u000a surface–atmosphere interactions versus to chaotic interannual atmospheric dynamics. Using a simple Monte Carlo approach, interannual\\u000a variability and linear trends in the SST-forced signal and potential predictability

Ian M. FergusonPhilip; Philip B. Duffy; Thomas J. Phillips; Xu Liang; John A. Dracup; Siegfried Schubert; Philip Pegion

2011-01-01

387

Pre-seismic geomagnetic anomaly and earthquake location  

NASA Astrophysics Data System (ADS)

Many researchers studied the relationships between appearances of geomagnetic anomalies and their distances to earthquake epicenters or faults. Yet, occasionally some magnetometer stations located nearby earthquake epicenters and/or faults do not observe geomagnetic anomalies. In this paper, a new hybrid system which simultaneously takes the hypocenter and fault plane solution into account is constructed to examine 38 earthquakes interpreted to be associated with geomagnetic anomalies during the period 1988-2001 in Taiwan. The Surface Magnetic Anomaly Reference Tip (SMART) of the new system is used instead of the epicenter or the fault to investigate statistically the distance relationship between the anomalies and the earthquake parameters. Results show that the anomalies gather along the fault and in the belt zone to the SMART. Possible mechanisms causing the anomalies in the two zones are proposed and discussed. Characteristics of the anomaly might shed some light on locations of faults before earthquake occurrences.

Chen, Chieh-Hung; Liu, Jann-Yenq; Lin, Pei-Ying; Yen, Horng-Yuan; Hattori, Katsumi; Liang, Wen-Tzong; Chen, Yuh-Ing; Yeh, Yih-Hsiung; Zeng, Xiaoping

2010-06-01

388

Neutral pion lifetime measurements and the QCD chiral anomaly  

E-print Network

A fundamental property of QCD is the presence of the chiral anomaly, which is the dominant component of the ?[superscript 0]??? decay rate. Based on this anomaly and its small (?4.5%) chiral correction, a prediction of the ...

Bernstein, Aron M.

389

Does Market Learning Explain the Disappearance of the Accrual Anomaly?  

E-print Network

This study investigates whether market learning explains the absence of the accrual anomaly in recent years by examining three conditions associated with the presence of the anomaly in prior research: (i) a differential relation between future...

Keskek, Sami

2012-10-19

390

Chlorination Disinfection By-Products in Drinking Water and Congenital Anomalies: Review and Meta-Analyses  

PubMed Central

Objectives The aim of this study was to review epidemiologic evidence, provide summary risk estimates of the association between exposure to chlorination disinfection by-products (DBPs) and congenital anomalies, and provide recommendations for future studies. Data sources and extraction We included all published epidemiologic studies that evaluated a relationship between an index of DBP exposure (treatment, water source, DBP measurements, and both DBP measurements and personal characteristics) and risk of congenital anomalies. When three or more studies examined the same exposure index and congenital anomaly, we conducted a meta-analysis to obtain a summary risk estimate comparing the highest exposure group with the lowest exposure group. When five or more studies examined total trihalomethane (TTHM) exposure and a specific congenital anomaly, we conducted a meta-analysis to obtain exposure–response risk estimates per 10 ?g/L TTHM. Data synthesis For all congenital anomalies combined, the meta-analysis gave a statistically significant excess risk for high versus low exposure to water chlorination or TTHM [17%; 95% confidence interval (CI), 3–34] based on a small number of studies. The meta-analysis also suggested a statistically significant excess risk for ventricular septal defects (58%; 95% CI, 21–107), but this was based on only three studies, and there was little evidence of an exposure–response relationship. We observed no statistically significant relationships in the other meta-analyses. We found little evidence for publication bias, except for urinary tract defects and cleft lip and palate. Conclusion Although some individual studies have suggested an association between chlorination disinfection by-products and congenital anomalies, meta-analyses of all currently available studies demonstrate little evidence of such an association. PMID:20019896

Nieuwenhuijsen, Mark J.; Martinez, David; Grellier, James; Bennett, James; Best, Nicky; Iszatt, Nina; Vrijheid, Martine; Toledano, Mireille B.

2009-01-01

391

The Leelanau Benzie And Grand Traverse, Michigan Anomalies - Structural And Geobotanical Indicators Of Hydrocarbon Microseepage  

NASA Astrophysics Data System (ADS)

Analysis of Landsat and Seasat imagery reveals several structural and geobotanical anomalies in the northwestern lower peninsula of Michigan. Integrating these surface anomalies with regional cross-sections and geophysical studies shows that they lie along predictable subsurface trends. These trends control hydrocarbon migration and accumulation; anomalies occur in both producing and untested portions of the trends. Subsequent to the acquisition and analysis of the satellite data, several "untested" areas have been drilled and successfully completed, suggesting that the anomalies are associated with hydrocarbon microseepage. The geobotanical and structural characteristics of Michigan are strongly affected by the last stage of Pleistocene glaciation. In moving through this portion of Michigan, the ice was deflected by a series of topographic features related to subsurface highs. This is indicated by the concave bends in the Port Huron and Manistee moraines, as well as the glacial lake terraces that formed along the edges of the northern topographic high as the ice retreated. The structural interpretation suggests that a large patch reef system may have existed in the northern portion of the study area during deposition of the Devonian Traverse Formation and the Silurian Niagara Group. The Traverse Formation underlies the Antrim Shale that outcrops below the glacial drift of the area. A large patch reef system would account for the differential movement of the ice since the associated limestones would be more resistant to erosion than the surrounding shales. In comparing the location of the geobotanical anomalies with the glacial deposits, an interesting interaction is revealed: over 75% of the anomalies are located in the more porous and permeable outwash deposits. Furthermore, every vegetation anomaly is associated with a lineament or lineament intersection on the structural interpretation. The geobotanical anomalies are also very transient. They appear only during the initial "leaf-out" in the spring and as areas of pre-senesence in the fall. During the summer months they are not visible. Apparently the microseepage visibly affects the vegetation only at those times of the year when the vegetation is in a natural state of flux or stress. This vegetation "stressing" also seems to be limited to the larger species of trees that have extensive root systems. This suggests that only the larger trees sample the deeper, more highly affected soil horizons.

Staskowski, Ronald J.

1984-08-01

392

On the mechanism of suggestion and hypnosis  

Microsoft Academic Search

The nature of hypnosis is not adequately explained by conditioned responses or conditioned attitudes. The writer agrees with R. W. White that the hypnotized subject must be motivated, but not necessarily to behave like a hypnotized person. She postulates, rather, that suggestions are effective only if the subject actively strives to imagine himself in the situation described by the operator.

M. B. Arnold

1946-01-01

393

Hinode 7: Conference summary and future suggestions  

NASA Astrophysics Data System (ADS)

This conclusion to the seventh Hinode science meeting (2013 November in Takayama, Japan) attempts to summarise what we have learnt during the conference (mainly from the review talks) about new observations from Hinode and about theories stimulated by them. Suggestions for future study are also offered.

Priest, Eric

2014-12-01

394

CALIFORNIA WATER VIRTUAL TOUR Suggested Further Reading  

E-print Network

. Regional Reports Volume 3. California Water Plan Update. Bulletin 16009 State of California, DepartmentCALIFORNIA WATER VIRTUAL TOUR Suggested Further Reading Water Law ­ Virginia Cahill Norris Hundley, Jr., The Great Thirst, Californians and Water: A History, University of California Press

Pasternack, Gregory B.

395

Seven Salutary Suggestions for Counselor Stamina  

ERIC Educational Resources Information Center

Counselor stamina is deemed essential in the midst of a consistently challenging, complex, and changing mental health care environment. Rather than perpetuating conversations about "burnout" and "burnout prevention," this article provides a salutary or health-promoting perspective. Seven suggestions for counselor stamina are presented and…

Osborn, Cynthia J.

2004-01-01

396

Current Research: 2013 Summer Reading Suggestions  

ERIC Educational Resources Information Center

To supplement the summer reading of National Science Teachers Association (NSTA) members, the NSTA Committee on Research in Science Education suggested a list of science education research articles that were published in the journals of NSTA's affiliates in 2012. These articles covered a variety of topics that include learning about…

Journal of College Science Teaching, 2013

2013-01-01

397

Qualitative Research Articles: Guidelines, Suggestions and Needs  

ERIC Educational Resources Information Center

Purpose: The purpose of this paper is to give ideas and suggestions to avoid some typical problems of qualitative articles. The aim is not to debate quality in qualitative research but to indicate some practical solutions. Design/methodology/approach: The paper discusses the design of qualitative research and the structure of a qualitative article…

Crescentini, Alberto; Mainardi, Giuditta

2009-01-01

398

Assessment of Achievement Motives: Comments and Suggestions  

Microsoft Academic Search

Nygård, R. & Gjesme, T. 1973. Assessment of Achievement Motives: Comments and Suggestions. Scand. J. educ. Res. 17, 39?46. Measuring instruments usually employed in achievement motivation research are reviewed and appraised. The following conclusions are drawn; (a) the validity of the need for achievement tests, especially when used among females, is questionable; (b) the objective tests assumed to indicate the

Roald Nygård; Torgrim Gjesme

1973-01-01

399

Technology Is Power: Suggestions for Beginning Teachers  

ERIC Educational Resources Information Center

Shanklin knows it can be hard for new teachers to incorporate all they know about technology with the realities of a classroom. She suggests setting incremental, monthly technology goals; investing in equipment; assessing students' grasp of the technology at their disposal and their use of it in classroom projects; searching purposefully for…

Shanklin, Nancy

2010-01-01

400

Physics Courses--Some Suggested Case Studies  

ERIC Educational Resources Information Center

To communicate the relevance and excitement of science activity to students, the use of more imaginative, and even openly speculative, case studies in physics courses is suggested. Some useful examples are Magnetic Monopoles, Constants, Black Holes, Antimatter, Zero Mass Particles, Tachyons, and the Bootstrap Hypothesis. (DF)

Swetman, T. P.

1972-01-01

401

SUGGESTIONS FOR MEASURING EXTERNAL CHARACTERS OF BIRDS  

Microsoft Academic Search

It is noted that there are no modern references thoroughly describing methods for mea- suring the external characteristics of birds. Perhaps this explains an all too frequent use of meth- ods that vary from suboptimal to inappropriate. Several common problems are addressed and functional solutions and methods are suggested for measuring external body components and body mass in birds. Some

Kevin Winker

1998-01-01

402

Suggested Universals in the Ontogenesis of Grammar.  

ERIC Educational Resources Information Center

This paper represents a preliminary attempt to determine universals of grammatical development in children. On the basis of language acquisition data, a limited number of findings are presented in the form of suggested developmental universals. These universals are grouped according to the psychological variables which may determine them, in the…

Slobin, Dan I.

403

Home Furnishings Merchandising. A Suggested Interdisciplinary Guide.  

ERIC Educational Resources Information Center

This curriculum guide contains three sections: introduction, curriculum material, and an annotated bibliography. Introductory information provides an overview of the home furnishings merchandising area, aptitudes needed, and career opportunities; discusses potential career ladders, which are divided into entry level, middle management, and…

Wray, Ralph D.; Hayden, Margaret B.

404

Woven Coronary Artery Anomaly Associated with Acute Coronary Syndrome  

PubMed Central

The woven coronary artery anomaly is a rare congenital anomaly in which a coronary artery is divided into thin channels that merge again into the distal lumen. Only a few cases of woven coronary artery have been reported in the literature. This anomaly is accepted as a benign condition. We describe a case of acute coronary syndrome in a patient with woven coronary artery anomaly. PMID:24436585

Ayhan, Selim; Ozturk, Serkan; Tekelioglu, Umit Yasar; Ocak, Tarik

2013-01-01

405

Testable polarization predictions for models of CMB isotropy anomalies  

SciTech Connect

Anomalies in the large-scale cosmic microwave background (CMB) temperature sky measured by the Wilkinson Microwave Anisotropy Probe have been suggested as possible evidence for a violation of statistical isotropy on large scales. In any physical model for broken isotropy, there are testable consequences for the CMB polarization field. We develop simulation tools for predicting the polarization field in models that break statistical isotropy locally through a modulation field. We study two different models: dipolar modulation, invoked to explain the asymmetry in power between northern and southern ecliptic hemispheres, and quadrupolar modulation, posited to explain the alignments between the quadrupole and octopole. For the dipolar case, we show that predictions for the correlation between the first 10 multipoles of the temperature and polarization fields can typically be tested at better than the 98% CL. For the quadrupolar case, we show that the polarization quadrupole and octopole should be moderately aligned. Such an alignment is a generic prediction of explanations which involve the temperature field at recombination and thus discriminate against explanations involving foregrounds or local secondary anisotropy. Predicted correlations between temperature and polarization multipoles out to l=5 provide tests at the {approx}99% CL or stronger for quadrupolar models that make the temperature alignment more than a few percent likely. As predictions of anomaly models, polarization statistics move beyond the a posteriori inferences that currently dominate the field.

Dvorkin, Cora [Kavli Institute for Cosmological Physics, Department of Astronomy and Astrophysics, and Enrico Fermi Institute, University of Chicago, Chicago Illinois 60637 (United States); Department of Physics, University of Chicago, Chicago Illinois 60637 (United States); Peiris, Hiranya V. [Kavli Institute for Cosmological Physics, Department of Astronomy and Astrophysics, and Enrico Fermi Institute, University of Chicago, Chicago Illinois 60637 (United States); Institute of Astronomy, University of Cambridge, Cambridge CB3 0HA (United Kingdom); Hu, Wayne [Kavli Institute for Cosmological Physics, Department of Astronomy and Astrophysics, and Enrico Fermi Institute, University of Chicago, Chicago Illinois 60637 (United States)

2008-03-15

406

Salinity anomaly as a trigger for ENSO events  

PubMed Central

According to the classical theories of ENSO, subsurface anomalies in ocean thermal structure are precursors for ENSO events and their initial specification is essential for skillful ENSO forecast. Although ocean salinity in the tropical Pacific (particularly in the western Pacific warm pool) can vary in response to El Niño events, its effect on ENSO evolution and forecasts of ENSO has been less explored. Here we present evidence that, in addition to the passive response, salinity variability may also play an active role in ENSO evolution, and thus important in forecasting El Niño events. By comparing two forecast experiments in which the interannually variability of salinity in the ocean initial states is either included or excluded, the salinity variability is shown to be essential to correctly forecast the 2007/08 La Niña starting from April 2007. With realistic salinity initial states, the tendency to decay of the subsurface cold condition during the spring and early summer 2007 was interrupted by positive salinity anomalies in the upper central Pacific, which working together with the Bjerknes positive feedback, contributed to the development of the La Niña event. Our study suggests that ENSO forecasts will benefit from more accurate salinity observations with large-scale spatial coverage. PMID:25352285

Zhu, Jieshun; Huang, Bohua; Zhang, Rong-Hua; Hu, Zeng-Zhen; Kumar, Arun; Balmaseda, Magdalena A.; Marx, Lawrence; Kinter III, James L.

2014-01-01

407

Salinity anomaly as a trigger for ENSO events.  

PubMed

According to the classical theories of ENSO, subsurface anomalies in ocean thermal structure are precursors for ENSO events and their initial specification is essential for skillful ENSO forecast. Although ocean salinity in the tropical Pacific (particularly in the western Pacific warm pool) can vary in response to El Niño events, its effect on ENSO evolution and forecasts of ENSO has been less explored. Here we present evidence that, in addition to the passive response, salinity variability may also play an active role in ENSO evolution, and thus important in forecasting El Niño events. By comparing two forecast experiments in which the interannually variability of salinity in the ocean initial states is either included or excluded, the salinity variability is shown to be essential to correctly forecast the 2007/08 La Niña starting from April 2007. With realistic salinity initial states, the tendency to decay of the subsurface cold condition during the spring and early summer 2007 was interrupted by positive salinity anomalies in the upper central Pacific, which working together with the Bjerknes positive feedback, contributed to the development of the La Niña event. Our study suggests that ENSO forecasts will benefit from more accurate salinity observations with large-scale spatial coverage. PMID:25352285

Zhu, Jieshun; Huang, Bohua; Zhang, Rong-Hua; Hu, Zeng-Zhen; Kumar, Arun; Balmaseda, Magdalena A; Marx, Lawrence; Kinter, James L

2014-01-01

408

Salinity anomaly as a trigger for ENSO events  

NASA Astrophysics Data System (ADS)

According to the classical theories of ENSO, subsurface anomalies in ocean thermal structure are precursors for ENSO events and their initial specification is essential for skillful ENSO forecast. Although ocean salinity in the tropical Pacific (particularly in the western Pacific warm pool) can vary in response to El Niño events, its effect on ENSO evolution and forecasts of ENSO has been less explored. Here we present evidence that, in addition to the passive response, salinity variability may also play an active role in ENSO evolution, and thus important in forecasting El Niño events. By comparing two forecast experiments in which the interannually variability of salinity in the ocean initial states is either included or excluded, the salinity variability is shown to be essential to correctly forecast the 2007/08 La Niña starting from April 2007. With realistic salinity initial states, the tendency to decay of the subsurface cold condition during the spring and early summer 2007 was interrupted by positive salinity anomalies in the upper central Pacific, which working together with the Bjerknes positive feedback, contributed to the development of the La Niña event. Our study suggests that ENSO forecasts will benefit from more accurate salinity observations with large-scale spatial coverage.

Zhu, Jieshun; Huang, Bohua; Zhang, Rong-Hua; Hu, Zeng-Zhen; Kumar, Arun; Balmaseda, Magdalena A.; Marx, Lawrence; Kinter, James L., III

2014-10-01

409

Rule-based expert system for maritime anomaly detection  

NASA Astrophysics Data System (ADS)

Maritime domain operators/analysts have a mandate to be aware of all that is happening within their areas of responsibility. This mandate derives from the needs to defend sovereignty, protect infrastructures, counter terrorism, detect illegal activities, etc., and it has become more challenging in the past decade, as commercial shipping turned into a potential threat. In particular, a huge portion of the data and information made available to the operators/analysts is mundane, from maritime platforms going about normal, legitimate activities, and it is very challenging for them to detect and identify the non-mundane. To achieve such anomaly detection, they must establish numerous relevant situational facts from a variety of sensor data streams. Unfortunately, many of the facts of interest just cannot be observed; the operators/analysts thus use their knowledge of the maritime domain and their reasoning faculties to infer these facts. As they are often overwhelmed by the large amount of data and information, automated reasoning tools could be used to support them by inferring the necessary facts, ultimately providing indications and warning on a small number of anomalous events worthy of their attention. Along this line of thought, this paper describes a proof-of-concept prototype of a rule-based expert system implementing automated rule-based reasoning in support of maritime anomaly detection.

Roy, Jean

2010-04-01

410

Boreal forest anomalies in the Yukon River Basin  

NASA Astrophysics Data System (ADS)

Boreal forests are being impacted by climate change though productivity declines (browning), increased fire extents, frequencies, and intensities, more abundant insects, a thickening active layer, and projected increases in deciduous forest components. Quantification of the regional boreal forest impacts in the Yukon River Basin was achieved though remote sensing and productivity modeling which separated weather and non-weather interannual variations in boreal forest productivity. This “ecosystem performance anomaly” approach uses weather data and coarse resolution (250m) Normalized Difference Vegetation Index (NDVI) time series information from the Moderate Resolution Imaging Spectroradiometer (MODIS). Regression tree models developed from 2000-2005 data were robust when applied to 2006-08 data and predicted interannual growing season NDVI with good accuracy (R2=0.84) Confidence intervals of 90 percent were used to determine anomalous vegetation responses to weather conditions. Boreal forest areas which underperformed relative to weather conditions were often associated with fire events, likely reflecting early stages of succession. Areas which overperformed, relative to weather conditions, were associated with Aspen and Birch establishment after older fires and in mesic areas. Time series analysis of performance anomalies tracked non-linear temporal responses which corresponded well with fire burn dates and fire perimeters. Stressed and changing boreal systems can be identified with this approach and boreal forest productivity projections can be made from future climate projections. These data sets can focus field studies and remediation. Potential climate change refugia can be assessed relative to current stressed systems and future expected boreal forest productivity.

Wylie, B. K.; Rover, J. A.; Murnahan, K.; Long, J.; Tieszen, L. L.; Brisco, B.

2010-12-01

411

Iridium anomaly in the Cretaceous section of the Eastern Kamchatka  

NASA Astrophysics Data System (ADS)

The origin of iridium anomalies is widely discussed with regard to massive fauna and flora extinction at several geologic boundaries. Two hypotheses are most popular, cosmogenic and volcanogenic. Anomalies of iridium are known at many stratigraphic levels, both at the geologic series borders and within geologic series. Our studies revealed increased content of iridium in a section of Cretaceous oceanic deposits on the Kamchatsky Mys Peninsula (Eastern Kamchatka, Russia). The investigated section (56°03.353´N, 163°00.376´E) includes interbedded jaspers and siliceous limestones overlaying pillow-basalts. These deposits belong to the Smagin Formation of the Albian-Cenomanian age. In the middle and upper parts of the section two beds of black carbonaceous rocks with sapropelic organic matter were observed. Their formation marked likely episodes of oxygen depletion of oceanic intermediate water (oceanic anoxic events). Our geochemical studies revealed an enrichment of the carbonaceous beds in a number of major and trace elements (Al2O3, TiO2, FeO, MgO, K2O, P2O5, Cu, Zn, Ni, Cr, V, Mo, Ba, Y, Zr, Nb, REE, U, Au, Pt etc.) in comparison with associating jaspers and limestones. There are likely different sources which contributed to the enrichment. It is possible however to correlate the excess of Al, Ti, Zr, Nb with volcanogenic admixture, which is absent in limestones and jaspers. A possible source of the volcanogenic material was local volcanism as suggested by the close association of the investigated section with volcanic rocks (basaltic lavas and hyaloclastites). The basalts of the Smagin Formation were previously proposed to originate during Cretaceous activity of the Hawaiian mantle plume (Portnyagin et al., Geology, 2008). Neutron activation analysis indicated increased up to 9 ppb concentration of Ir at the bottom of the lower carbonaceous bed (inorganic part of the sample was analyzed comprising 46% of the bulk rock). In other samples Ir content was below the detection limit of the technique (< 2 ppb). The iridium anomaly was found for the fist time in sedimentary section in Kamchatka. This anomaly correlates in the studied section with a positive shift of d13C. Taking into account radiolarian age data (Palechek et al., 2010) this allows to correlate the anomaly with the Middle Cenomanian oceanic anoxic event (MCE). In our interpretation, the formation of the carbonaceous beds could be related to local outbreaks of volcanism which resulted in upwelling of deep waters enriched by mineral substances, sharp increase of plankton biological productivity and oxygen depletion of intermediate waters. Anoxic conditions favored enrichment of the sedimentary deposits in PGE sourced from lavas and hyaloclastites. Thus, iridium anomaly which has been found in Cretaceous sediments in Kamchatka, likely originates from a local volcanic source. This work was supported by the Russian-German project KALMAR and RFBR grant No. 10-05-00065.

Savelyev, Dmitry; Savelyeva, Olga

2010-05-01

412

New magnetic anomaly map of the East Antarctic continental margin  

NASA Astrophysics Data System (ADS)

Marine magnetic survey coverage of the southern part of Indian Ocean is to a certain extent limited for defining the magnetic pattern of the continental margin of East Antarctica. The USA research vessels collected the bulk of the marine magnetic data in the beginning of 1960's. During the succeeding years Australian, German, Japanese, Russian and other international scientific programs made major contributions to the network of marine magnetic data. Since the beginning of new century only two nations (Russian and Australian) have acquired the marine magnetic data in the southern part of Indian Ocean. The marine surveys in the Cosmonaut Sea, the western part of the Cooperation Sea in the Davis and Mawson Seas were accomplished by the PMGRE in 2000-2009 field seasons. The marine magnetic data collected during two seasons (2001-2002) within the AASOPP Project which was established in early 2000 to define the outer limits of the continental shelf offshore of the Australian Antarctic Territory (AAT) covered the full length of the AAT from 40OE to 160OE. The new magnetic anomaly map of the East Antarctic continental margin incorporates all available data acquired by the international community since the IGY 1957-58 through to 2009. Results of the compilation do not radically alter recent models describing first-order motions between the Antarctic, Australian and Indian plates, but they help to resolve uncertainties in early break-up history of opening between these plates. The timing and direction of early seafloor spreading in the area off the Antarctic margin, once conjugate to part of the Southern Greater Indian margin and to Australian margin, along the largely unknown region of the Enderby Basin, Davis Sea and Mawson Sea has been analyzed by many authors using different data sets. It is highly likely that spreading in the Enderby Basin occurred around the same time as the well documented M-sequence (anomalies M10 to M0) off the Perth Basin, Western Australia (Powell et al. 1988). The history of the early spreading is complicated further by the likelihood of one or several ridge jumps in which most early seafloor crust was transferred to the Antarctic plate and the Elan Bank micro-continent was isolated from the Indian continent (Muller et al. 2001). Additionally, a large amount of the seafloor crust is now probably overprinted by igneous activity associated with the Kerguelen Plume, which began forming the Kerguelen LIP from about 120-110 Ma. However all available results of interpretations do not match to the magnetic anomaly pattern which can be distinguished by the newly compiled map. Our observations suggest that this is especially correct to the Enderby Basin and to lesser degree for the region that was conjugate to Australia. The prominent magnetic anomaly boundary signal and sharp basement step correlated with the MacRobertson Coast Anomaly or the Enderby Basin Anomaly (Golynsky et al., 2007) is not observed elsewhere in the Enderby Basin, Princess Elizabeth Trough or Davis Sea. In the central Enderby Basin there some evidences for an abandoned ‘fossil' spreading centre that might continue to the west of the Kerguelen Plateau, east of Gunnerus Ridge. The estimated timing of its extinction corresponding to the early surface expression of the Kerguelen Plume at the Southern Kerguelen Plateau around 120 Ma and the subsequent formation of the Elan Bank microcontinent. Alternatively, the ridge jump occurred only in the central Enderby basin, due to the proximity of the Kerguelen plateau, whereas seafloor spreading continued in the western Enderby basin and conjugate south of Sri Lanka basin.

Golynsky, Alexander; Ivanov, Sergey; Kazankov, Andrey

2010-05-01

413

Metastable liquid-liquid phase transition in a single-component system with only one crystal phase and no density anomaly.  

PubMed

We investigate the phase behavior of a single-component system in three dimensions with spherically-symmetric, pairwise-additive, soft-core interactions with an attractive well at a long distance, a repulsive soft-core shoulder at an intermediate distance, and a hard-core repulsion at a short distance, similar to potentials used to describe liquid systems such as colloids, protein solutions, or liquid metals. We showed [Nature (London) 409, 692 (2001)] that, even with no evidence of the density anomaly, the phase diagram has two first-order fluid-fluid phase transitions, one ending in a gas-low-density-liquid (LDL) critical point, and the other in a gas-high-density-liquid (HDL) critical point, with a LDL-HDL phase transition at low temperatures. Here we use integral equation calculations to explore the three-parameter space of the soft-core potential and perform molecular dynamics simulations in the interesting region of parameters. For the equilibrium phase diagram, we analyze the structure of the crystal phase and find that, within the considered range of densities, the structure is independent of the density. Then, we analyze in detail the fluid metastable phases and, by explicit thermodynamic calculation in the supercooled phase, we show the absence of the density anomaly. We suggest that this absence is related to the presence of only one stable crystal structure. PMID:12513478

Franzese, G; Malescio, G; Skibinsky, A; Buldyrev, S V; Stanley, H E

2002-11-01

414

Parametric Methods for Anomaly Detection in Aggregate Traffic  

E-print Network

estimate model parameters in real- time, thus obviating the need for a long training phase or manual detection time and the strength of an anomaly. Additionally, it uses both traffic-rate and packet of packet sizes from the nominal condition is flagged as an anomaly. Our anomaly detection problem is posed

Heidemann, John

415

Five-Year Average Global Temperature Anomalies 1880 - 2010  

NSDL National Science Digital Library

This color-coded map displays a progression of changing five-year average global surface temperatures anomalies from 1880 through 2010. The final frame represents global temperature anomalies averaged from 2006 to 2010. The temperature anomalies are computed relative to the base period 1951-1980.

Schmunk, Robert B.; Hansen, J.; Ruedy, R.; Sato, Mki; Lo, K.; Studio, Nasa/goddard S.

416

Harmonic superspace formalism and the consistent chiral anomaly  

SciTech Connect

The harmonic superspace formalism has been used to construct the consistent chiral anomaly in N = 1, d = 6 supersymmetric Yang-Mills thoery. The expressions of the gauge anomaly ..delta../sub s//sup phi/ and of the supersymmetric anomaly ..delta../sub SUSY//sup phi/ are given together with the consistent condition. 7 refs.

Li, W.

1986-08-01

417

Geology of areas marked by geophysical anomalies (B-35 and B-34), Wadi Bidah District, Kingdom of Saudi Arabia  

USGS Publications Warehouse

Geophysical surveys in the Wadi Bidah district, in the southwestern part of the Kingdom of Saudi Arabia, have revealed anomalies of the type that may be caused by deposits of massive sulfides. Accordingly, a study was undertaken to investigate the geologic environment associated with the geophysical anomalies and to determine whether mineral exploration of the anomalous areas might be warranted. An extensive geochemical sampling program did not disclose any evidence of ore mineral concentrations in the rocks. Detailed geologic mapping shows the anomalous areas to be underlain by Precambrian carbonaceous graywacke, the outcrop patterns of which closely fit the anomaly patterns. Field evidence and petrologic studies indicate that carbonaceous material in the rocks is the cause of the geophysical anomalies. Nothing was found in the anomalous areas that suggests the presence of mineral deposits of commercial grade, and further mineral investigations or exploration in the areas is not recommended.

Kiilsgaard, T.H.

1982-01-01

418

El Nino: Sea Surface Temperature Anomaly and Sea Surface Height Anomaly from Sept. 1996 to Sept. 1997  

NSDL National Science Digital Library

Sea surface height anomaly is presented as topography and sea surface temperature anomaly as color. A similar visualization (animation 1415) presents this same data and includes a pan from the front view to a side view.

Shirah, Greg; Busalacchi, Antonio

1997-09-08

419

Coronal Abundance Anomalies in Solar-Like Stars  

NASA Astrophysics Data System (ADS)

We propose to model the trend of coronal abundance anomalies observed in a sample of solar-like stars by Wood & Linsky (2010). Dwarf stars of similar spectral type to the Sun show what has become known as a FIP (First Ionization Potential) Effect, where elements with first ionization potential below about 10 eV are enhanced in abundance in the corona by a factor of about 3 - 4. Stars of later spectral type show a diminished FIP effect, with the anomaly disappearing at about K5 spectral type. Beyond this, M dwarf stars show an inverse FIP effect, with the low FIP ions becoming depleted in the stellar corona, by factors of order 2.5 - 3. The solar case of positive FIP effect has been successfully interpreted as being due to the action of the ponderomotive force associated with chromospheric Alfven waves. In conditions in which upgoing Alfven waves are transmitted into coronal loops, or in which coronally generated waves reflect at loop footpoints, the ponderomotive force is directed upwards, and accelerates chromospheric ions (the low FIP elements) into the corona. Neutral atoms are not affected. The inverse FIP effect can arise when upward propagating chromospheric Alfven waves are reflected back down again at coronal loop footpoints, due to a mismatch between the wave frequency and the loop resonance. We propose to study stars for which parameters like asteroseismic oscillation frequencies, coronal abundance anomalies, and chromospheric structure are known. As well as constraining coronal magnetic fields and loop resonances in these stars, we expect important insights into the nature of stellar dynamos since the M dwarfs in the sample (with inverse FIP effect) are at or near the fully convective limit. Finally, we will be able to assess potential fractionation in the O/Ne abundance ratio. Drake & Testa (2005) argued that Ne is depleted in the solar corona relative to O, but not in the coronae of more active stars. Our FIP models provide some support for this in the solar case, and it will be interesting to study O/Ne fractionation predicted in various stellar cases. The work supports the NASA Strategic Goal: Discover the origin, structure, evolution and destiny of the universe, and search for Earth-like planets, through understanding how stars evolve and affect their surroundings.

Laming, John

420

Mentoring in biostatistics: some suggestions for reform  

PubMed Central

Mentoring is routinely used as a tool to facilitate acquisition of skills by new professionals in fields like medicine, nursing, surgery, and business. While mentoring has been proposed as an effective strategy for knowledge and skills transfer in biostatistics and related fields, there is still much to be done to facilitate adoption by stakeholders, including academia and employers of biostatisticians. This is especially troubling given that biostatisticians play a key role in the success or otherwise of clinical research conducted for evidence-based decisions. In this paper, we offer suggestions on how mentoring can be applied in practice to advance the statistical training of future biostatisticians. In particular, we propose steps that academic statistics departments, professional statistical societies, and statistics organizations can take to advance the mentoring of young biostatisticians. Our suggestions also cover what mentors and mentees can do to facilitate a successful mentoring relationship. PMID:23093907

Odueyungbo, Adefowope; Thabane, Lehana

2012-01-01

421

A Suggestion for a Fast Multiplier  

Microsoft Academic Search

It is suggested that the economics of present large-scale scientific computers could benefit from a greater investment in hardware to mechanize multiplication and division than is now common. As a move in this direction, a design is developed for a multiplier which generates the product of two numbers using purely combinational logic, i.e., in one gating step. Using straightforward diode-transistor

C. S. Wallace

1964-01-01

422

Suggested Plan of Study BS Mathematics  

E-print Network

: Math 118A Math 118B 118C or elective UD elective 147A or elective *Computer Science 8 or 16Suggested Plan of Study BS Mathematics 10/21/14 Fall Winter Spring Summer? Frosh year: Math 3A Math 3B Math 4A CMPSC* Physics 1, 6A or 21 Soph. year: Math 4B Math 6A Math 6B Math 8** Math 108A*** Math

Akhmedov, Azer

423

Suggested Plan of Study BS Mathematical Sciences  

E-print Network

elective Sr. year: Math 118A Math 118B 118C or UD elective UD elective 122A *Computer Science 8 or 16Suggested Plan of Study BS Mathematical Sciences 10/21/14 Fall Winter Spring Summer? Frosh year: Math 3A Math 3B Math 4A CMPSC* Physics 1, 6A or 21 Soph. year: Math 4B Math 6B Math 108A*** Math 6A

Akhmedov, Azer

424

An analysis of the relationship between cloud anomalies and sea surface temperature anomalies in a global circulation model  

NASA Technical Reports Server (NTRS)

The relationship between the sea surface temperature anomalies (SSTAs) and the anomalies of the monthly mean cloud cover (including the high-level, low-level, and total cloud cover), the outgoing longwave radiation, and the reflected solar radiation was analyzed using a least absolute deviations regression at each grid point over the open ocean for a 6-yr period. The results indicate that cloud change in association with a local 1-C increase in SSTAs cannot be used to predict clouds in a potential future world where all the oceans are 1-C warmer than at present, because much of the observed cloud changes are due to circulation changes, which in turn are related not only to changes in SSTAs but to changes in SSTA gradients. However, because SSTAs are associated with changes in the local ocean-atmosphere moisture and heat fluxes as well as significant changes in circulation (such as ENSO), SSTAs can serve as a surrogate for many aspects of global climate change.

Peterson, Thomas C.; Barnett, Tim P.; Roeckner, Erich; Vonder Haar, Thomas H.

1992-01-01

425

Impact of Sea Surface Temperature Anomalies on Medieval Drought in North America  

NASA Astrophysics Data System (ADS)

Multiple lines of evidence suggest that so-called ';megadroughts' affected North America during the medieval times (MT) that lasted from approximately 900-1300 AD. This study used the NCAR Community Atmospheric Model (CAM5) to evaluate the remote effects of SST anomalies on medieval drought in North America. A series of model experiments were conducted to ferret out the relative roles of individual oceans (e.g., the tropical Pacific, North Atlantic and the tropical Indian Ocean), as well as the entire global ocean in accounting for the medieval megadroughts. When driven by reconstructed SST anomalies over the oceans globally, the model can well simulate drought intensity and areal extent in North America during the MT. The roles of individual oceans on the medieval drought vary, but none of them significantly affect the drought in North America. The tropical Pacific Ocean, however, played a relatively more important role on the medieval drought compared to other oceans. Our study suggests that the medieval drought in North America was caused by the global SST anomalies rather than tropical Pacific or North Atlantic SST anomalies alone. The atmospheric circulations and other physical mechanisms behind the medieval drought were also examined.

Zhang, Y.; Feng, S.; Oglesby, R. J.

2013-12-01

426

Structural Setting of the Emerson Pass Geothermal Anomaly, Pyramid Lake Paiute Reservation, Western Nevada  

NASA Astrophysics Data System (ADS)

The Pyramid Lake area is favorable for geothermal development due to the tectonic setting of the region. The Walker Lane belt, a dextral shear zone that accommodates ~20% relative motion between the Pacific and North American plates, terminates northwestward in northeast California. NW-directed dextral shear is transferred to WNW extension accommodated by N-to -NNE striking normal faults of the Basin and Range. As a consequence, enhanced dilation occurs on favorably or