bluuebunny/crossref_metadata_2025 huggingface dataset:
The Swan Brand: Reframing the Legacy of Anna Pavlova
Authors: Fisher Jennifer
Published: March 2012

How does legendary status evolve in the world of ballet? Are the most brilliant dance figures simply bound to be recognized by the public and discerning critics alike? Or does historical importance depend on specific strategies? Or on the serendipity of circumstance? Joan Acocella notes that genius owes much to “ego strength” as well as luck (2007, xii). Perhaps the element of fame is always interlocked with market forces, even in the dance world, where artists are affected by what is written about them, whether it appears in influential places, and how much can be gained by selling an image. But how does history arrive at the consideration of a dance legend's substance and contributions? Being respected in the long run might inevitably depend on a combination of circumstances, including whether the popular imagination or the attention of academics can be captured. In the case of Russian ballerina Anna Pavlova, a legend has grown around a particular set of glorifying associations. My question here is whether or not these associations, while celebrating Pavlova as a dance “star,” have also limited consideration of her as a significant figure in dance history. Often categorized as “old-fashioned” and “conservative,” Pavlova was in fact an innovator, I suggest, in terms of the way she combined ballet and dance influences from around the world, as well as her role in revivals of neglected dance forms, and, lastly, in her rhetorical framing of ballet as a serious endeavor and an empowering pursuit for women.
Dance Discourses: Keywords In Dance Research
Authors: Lepecki André
Published: March 2012

The formation of what Randy Martin has called “critical dance studies” (1998) has gained increased momentum over the past decade. Martin's notion of critical dance studies clarified how dance scholarship was being reshaped by the explicit inclusion of critical theory in its methodologies and epistemologies. One of the major consequences for dance studies in embracing critical theory was the identification of dancing and choreographic practices as being also theory. Understanding dance as theory is not equivalent to seeing dance as the sole provider of the theoretical tools it needs for its own analysis (this would be intolerably solipsistic). Rather, it means that dance becomes a privileged practice ready to provide analytical tools for theorizing other areas of social performances: politics, culture, formations of disciplines and their bodies (docile or resistant). Dance is a mode of theorization that theory itself would need in order to address the social and political problematic brought by issues close to dance such as mobilization, embodiment, subjectivities, participation, representation, desire, discipline, control, etc.
Study of stimulated Brillouin scattering in extended paraxial region
Authors: Sharma Prerana , Bhardwaj A.K. , Sharma R.P.
Published: March 2012

This communication presents a comparison of two cases to study the process of laser beam propagation and Stimulated Brillouin Scattering (SBS) in laser plasma interaction. These two cases are, with imposing the restriction of paraxial approximation on the laser beam and, relaxing this restriction up to a certain extent. In this work, the study done by Sharma et al. (2009) using paraxial approximation is extended by taking contribution of the off-axial rays in the laser beam profile. The spitted profile of the laser beam is obtained due to uneven focusing of the off-axial rays and its effect on localization of the ion acoustic wave (IAW) has been studied. Including the off-axial part of the laser beam semi-analytical solution of the nonlinear coupled IAW equation has been found and this is examined that off-axial part affects background densities. The nonlinear coupling between the laser beam and IAW is severely affected by modified profile of the laser beam. Further, it is investigated that the SBS is also influenced by this coupling process. Therefore, the reflectivity of SBS has been compared with and without contribution of off-axial rays. A notable change is found in the magnitude of SBS reflectivity in modified-paraxial case in comparison to the paraxial case.
SOCIAL JUSTICE, GENOMIC JUSTICE AND THE VEIL OF IGNORANCE: HARSANYI MEETS MENDEL
Authors: Okasha Samir
Published: March 2012

John Harsanyi and John Rawls both used the veil of ignorance thought experiment to study the problem of choosing between alternative social arrangements. With his ‘impartial observer theorem’, Harsanyi tried to show that the veil of ignorance argument leads inevitably to utilitarianism, an argument criticized by Sen, Weymark and others. A quite different use of the veil-of-ignorance concept is found in evolutionary biology. In the cell-division process called meiosis, in which sexually reproducing organisms produce gametes, the chromosome number is halved; when meiosis is fair, each gene has only a fifty percent chance of making it into any gamete. This creates a Mendelian veil of ignorance, which has the effect of aligning the interests of all the genes in an organism. This paper shows how Harsanyi's version of the veil-of-ignorance argument can shed light on Mendelian genetics. There turns out to be an intriguing biological analogue of the impartial observer theorem that is immune from the Sen/Weymark objections to Harsanyi's original.
Children's ability to answer different types of questions
Authors: SALOMO DOROTHÉ , LIEVEN ELENA , TOMASELLO MICHAEL
Published: March 2012

Young children answer many questions every day. The extent to which they do this in an adult-like way – following Grice's Maxim of Quantity by providing the requested information, no more no less – has been studied very little. In an experiment, we found that two-, three- and four-year-old children are quite skilled at answering argument-focus questions and predicate-focus questions with intransitives in which their response requires only a single element. But predicate-focus questions for transitives – requiring both the predicate and the direct object – are difficult for children below four years of age. Even more difficult for children this young are sentence-focus questions such as “What's happening?”, which give the child no anchor in given information around which to structure their answer. In addition, in a corpus study, we found that parents ask their children predicate-focus and sentence-focus questions very infrequently, thus giving children little experience with them.
Estimating AIS Coverage from Received Transmissions
Authors: Hammond T. R. , Peters D. J.
Published: March 2012

This paper proposes a new method for estimating Automatic Identification System (AIS) coverage empirically from received transmissions. The method is appropriate for stationary coverage assets, as distinct from aircraft and satellites. The key idea behind the method is to interpolate probabilistically between AIS reports in order to reconstruct where the missed transmissions might have occurred. These hypothetical missed transmissions then supplement the received ones in a coverage estimate based on a Bayesian treatment of a binomial model of reception. The final estimate of the coverage is implemented over a spatial grid. The method is demonstrated on simulated AIS data and was found to have lower mean squared error than a previously published method. Assumptions and potential weaknesses of the new method are discussed.
Network-based Collaborative Navigation in GPS-Denied Environment
Authors: Lee Jong Ki , Grejner-Brzezinska Dorota A. , Toth Charles
Published: March 2012

Global Positioning System (GPS) has been used as a primary source of navigation in land and airborne applications. However, challenging environments cause GPS signal blockage or degradation, and prevent reliable and seamless positioning and navigation using GPS only. Therefore, multi-sensor based navigation systems have been developed to overcome the limitations of GPS by adding some forms of augmentation. The next step towards assured robust navigation is to combine information from multiple ground-users, to further improve the chance of obtaining reliable navigation and positioning information. Collaborative (or cooperative) navigation can improve the individual navigation solution in terms of both accuracy and coverage, and may reduce the system's design cost, as equipping all users with high performance multi-sensor positioning systems is not cost effective. Generally, ‘Collaborative Navigation’ uses inter-nodal range measurements between platforms (users) to strengthen the navigation solution. In the collaborative navigation approach, the inter-nodal distance vectors from the known or more accurate positions to the unknown locations can be established. Therefore, the collaborative navigation technique has the advantage in that errors at the user's position can be compensated by other known (or more accurate) positions of other platforms, and may result in the improvement of the navigation solutions for the entire group of users. In this paper, three statistical network-based collaborative navigation algorithms, the Restricted Least-Squares Solution (RLESS), the Stochastic Constrained Least-Squares Solution (SCLESS) and the Best Linear Minimum Partial Bias Estimation (BLIMPBE) are proposed and compared to the Kalman filter. The proposed statistical collaborative navigation algorithms for network solution show better performance than the Kalman filter.
Improving the Estimation of Uncalibrated Fractional Phase Offsets for PPP Ambiguity Resolution
Authors: Li Xingxing , Zhang Xiaohong
Published: March 2012

Integer ambiguity resolution in Precise Point Positioning (PPP) can shorten convergence time and improve accuracy significantly. Uncalibrated Fractional Offsets (UFOs) originating in the satellites destroy the integer nature of carrier phase ambiguities observed at a single station. Several methods have been developed to estimate UFO information from a reference network for PPP ambiguity resolution. In this paper, we present a new approach for estimating Zero-Differenced (ZD) UFOs via float ZD ambiguities from a reference network. In this new approach, UFOs for receivers and satellites are estimated in an integrated adjustment with integer ambiguities being resolved sequentially, so that UFOs of higher quality can be achieved. The float ZD ambiguities used in the estimation can be from network or PPP solutions. Using those from PPP solutions enables the time-consuming clock estimations and the UFO estimations to be carried out separately, so that UFOs can be estimated more reliably from a much denser network. In this paper, a data processing procedure, from the estimation of UFOs through to PPP ambiguity fixing, is designed and proposed. The approach is validated with several data sets in various scenarios. The results show that satellite UFOs can be estimated precisely and reliably by using the observations from a reference network, in which the station spacing could be up to thousands of kilometres. With 30 minutes of observations, a PPP solution with fixed integer ambiguities is achievable and the positioning accuracy can be improved significantly when compared with its float solution.
Assessment of GNSS Orthogonal Transformation Model
Authors: Chen Wantong , Zhang Yanzhong
Published: March 2012

GNSS relative positioning technique is an important field of study, in which the standard ‘GNSS Baseline Model’ is often used. Differencing between observation equations is used to construct the mathematical model, since this method can eliminate some common errors in the GNSS signal measurements. The ‘Orthogonal Transformation’ method can also construct the GNSS Baseline Model. However, as is described by some scholars, this model may avoid some drawbacks of Double Differencing (DD) while maintaining all the advantages. For comparison purposes, this model is evaluated and the theoretical equivalence of both approaches is proved for the short baseline from two aspects: the Integer Ambiguity Resolution and the conditional least-squares baseline vector.
The science on front-of-package food labels
Authors: Hawley Kristy L , Roberto Christina A , Bragg Marie A , Liu Peggy J , Schwartz Marlene B , Brownell Kelly D
Published: March 2012

Objective

The US Food and Drug Administration and Institute of Medicine are currently investigating front-of-package (FOP) food labelling systems to provide science-based guidance to the food industry. The present paper reviews the literature on FOP labelling and supermarket shelf-labelling systems published or under review by February 2011 to inform current investigations and identify areas of future research.

Design

A structured search was undertaken of research studies on consumer use, understanding of, preference for, perception of and behaviours relating to FOP/shelf labelling published between January 2004 and February 2011.

Results

Twenty-eight studies from a structured search met inclusion criteria. Reviewed studies examined consumer preferences, understanding and use of different labelling systems as well as label impact on purchasing patterns and industry product reformulation.

Conclusions

The findings indicate that the Multiple Traffic Light system has most consistently helped consumers identify healthier products; however, additional research on different labelling systems’ abilities to influence consumer behaviour is needed.
The 15N natural abundance of the N lost from an N‐saturated subtropical forest in southern China
Authors: Koba Keisuke , Fang Yunting , Mo Jiangming , Zhang Wei , Lu Xiankai , Liu Lei , Zhang Tao , Takebayashi Yu , Toyoda Sakae , Yoshida Naohiro , Suzuki Keisuke , Yoh Muneoki , Senoo Keishi
Published: March 2012

The 15N‐enrichment of plants and soils is believed to indicate characteristics of the open nitrogen (N) cycle in terrestrial ecosystems because N lost from an ecosystem is presumably 15N‐depleted through isotopic fractionation. However, because of a lack of an appropriate analytical methodology to confirm that supposition, the δ15N value for total dissolved nitrogen (TDN, the sum of ammonium, nitrate, and dissolved organic N) in stream water from forests has been measured only rarely. This report describes the δ15N values for TDN, ammonium, and nitrate in precipitation and stream water, together with those for soil‐emitted nitrous oxide (N2O; measured once) in an N‐saturated subtropical forest in southern China. Concentration‐weighted δ15N values of TDN were −0.7‰ in precipitation and +1.2‰ in stream water. The difference in δ15N between soil (+3.9‰) and TDN in the stream water was 2.7‰. In contrast, soil‐emitted N2O was strongly 15N‐depleted (−14.3‰): 18‰ lower than that of the soil. Our results demonstrate that the discharged N loss is 15N‐depleted only slightly compared with soil N, and gaseous N losses can be a strong driver for raising the terrestrial ecosystem δ15N. Our findings suggest that the relation between ecosystem δ15N and the open N cycle can be interpreted better by considering the net discrimination against 15N determined by the balance between gaseous and discharge N losses. Steady state 15N budget calculations proposed by Houlton and Bai (2009) can provide important information about the gaseous N fluxes, which are difficult to measure directly. The steady state calculation for the relationships among gaseous N loss, apparent isotopic fractionation during gaseous N loss, and isotopic signature of N inputs suggests that precise measurements of unmeasured components (e.g., dry deposition, NO and N2 emission) are quite important for better estimation of gaseous N losses from the ecosystem.
On TIE‐GCM simulation of the evening equatorial plasma vortex
Authors: Rodrigues F. S. , Crowley G. , Heelis R. A. , Maute A. , Reynolds A.
Published: March 2012

It has already been shown that the Thermosphere‐Ionosphere‐Electrodynamics General Circulation Model (TIE‐GCM) is capable of reproducing the pre‐reversal enhancement (PRE) of the equatorial zonal electric field. However, the ability of TIE‐GCM to reproduce the post‐sunset plasma vortex, an important feature of the evening equatorial ionosphere closely related to the PRE, has been overlooked and had yet to be addressed. In order to address the ability of TIE‐GCM to reproduce the vortex, we examined model simulations of the plasma flow pattern in the geomagnetic equatorial plane and compared the simulations with ground‐based radar observations. We found that TIE‐GCM is indeed capable of reproducing the overall features of the post‐sunset equatorial plasma vortex pattern. We also found that both E and F region dynamos in TIE‐GCM dictate the main features of the vertical shear in the zonal plasma drifts that is part of the evening vortex. The contribution of vertical currents to the shear, however, is not negligible. Comparison of simulation results with radar measurements of the vortex indicates that the model can still be improved to better match the observations.
Frictional behavior of oceanic transform faults and its influence on earthquake characteristics
Authors: Liu Yajing , McGuire Jeffrey J. , Behn Mark D.
Published: March 2012

We use a three‐dimensional strike‐slip fault model in the framework of rate and state‐dependent friction to investigate earthquake behavior and scaling relations on oceanic transform faults (OTFs). Gabbro friction data under hydrothermal conditions are mapped onto OTFs using temperatures from (1) a half‐space cooling model, and (2) a thermal model that incorporates a visco‐plastic rheology, non‐Newtonian viscous flow and the effects of shear heating and hydrothermal circulation. Without introducing small‐scale frictional heterogeneities on the fault, our model predicts that an OTF segment can transition between seismic and aseismic slip over many earthquake cycles, consistent with the multimode hypothesis for OTF ruptures. The average seismic coupling coefficientχ is strongly dependent on the ratio of seismogenic zone width W to earthquake nucleation size h*; χ increases by four orders of magnitude as W/h* increases from ∼1 to 2. Specifically, the average χ = 0.15 ± 0.05 derived from global OTF earthquake catalogs can be reached at W/h* ≈ 1.2–1.7. Further, in all simulations the area of the largest earthquake rupture is less than the total seismogenic area and we predict a deficiency of large earthquakes on long transforms, which is also consistent with observations. To match these observations over this narrow range of W/h* requires an increase in the characteristic slip distance dcas the seismogenic zone becomes wider and normal stress is higher on long transforms. Earthquake magnitude and distribution on the Gofar and Romanche transforms are better predicted by simulations using the visco‐plastic model than the half‐space cooling model.
Assessment and development of a sediment model within an operational system
Authors: Sykes Peter A. , Barciela Rosa M.
Published: March 2012

The Medium Resolution Continental Shelf (MRCS) modeling system is a coupled hydrodynamic plus sediment (POLCOMS) and ecosystem (ERSEM) model covering the UK shelf region. It is run operationally at the Met Office providing daily analyses and 5‐day forecasts for a variety of fields. The output of the sediment model within the MRCS system has been assessed against CEFAS SmartBuoy turbidity data and satellite‐retrieved surface sediment concentration for the period 2008 to 2009. The results of the assessment showed poor variability throughout the year highlighted by low correlations and large differences in standard deviations between the model and observations. In light of these results, the sediment model parameterizations for the mechanisms of erosion, deposition and settling were modified and the model was further developed by incorporating an aggregation/disaggregation scheme. The initialization method was also reviewed and updated. Assessment of this collection of developments showed significant improvements in variability as well as improvements in the quantitative match to the observations. Improvements were seen in correlations, mean values, standard deviations and percent differences throughout the assessment period. As a result of sensitivity studies it was found that each of the model developments had different impacts on improving the model predictions. All the model developments had a quantitative impact on the predicted surface sediment concentration with the aggregation acting to constrain the increase in sediment brought about by the erosion and settling. The changes in erosion and settling predominantly accounted for the improvement in correlation between the model and satellite observations.
From seismic noise to ocean wave parameters: General methods and validation
Authors: Ardhuin Fabrice , Balanche Abel , Stutzmann E. , Obrebski Mathias
Published: March 2012

Seismic noise is an indirect source of information on ocean waves. Using a model of noise generation and propagation, seismic stations can be separated into those that are mostly sensitive to local sea states, and those that integrate sources from a large oceanic area. The model also provides a classification of noise‐generating sea states into three classes. The analysis of Central California seismic noise data, well correlated with local waves, reveals that class I events dominate in summer, caused by a single wind‐sea system, and for which ocean wave spectral levels are proportional to seismic spectral levels to an exponentb ≃ 0.9. In winter, noise is dominated by class II generation, for which coastal reflection is important, with a wave spectral density roughly proportional to the seismic spectral density to an exponent b ≃ 0.7. Sporadic events of class III probably produce some of the strongest noise events in Central California and need to be properly screened. These events are caused by opposed wave systems that are usually the wind‐sea and a swell. This noise classification can be used to improve on the correlation between measured and estimated wave heights (up tor = 0.93 for daily averages). For other locations, where remote oceanic sources are recorded, a significant wave height estimated from the seismic noise compares well with area‐averaged satellite data or wave model results (r > 0.85 for daily averages). These analyses pave the way for quantitative uses of seismic records, including the reconstruction of past wave climates, and the calibration of wave hindcasts.
The combined influence of hydrodynamic forcing and calcification on the spatial distribution of alkalinity in a coral reef system
Authors: Zhang Zhenlin , Falter James , Lowe Ryan , Ivey Greg
Published: March 2012

We investigated the influence of hydrodynamic forcing (waves, tides, alongshore currents and winds) and net calcification by coral reef organisms on the spatial distribution of total alkalinity (TA) in a fringing reef system through a combination of field measurements and numerical modeling. A field experiment was conducted over 10 days in Coral Bay (Ningaloo Reef, Western Australia) during which we measured wave heights, currents, and tides as well as the spatial distribution of TA across the fore reef, reef crest, and lagoon. We used observed changes in TA on the adjacent reef flat, along with synoptic measurements of cross‐reef transport, to estimate in situ rates of net calcification (gcv) using a control volume approach. Based on the gcv estimated, we simulated light‐driven, diurnal variations in benthic net calcification within a three‐dimensional ocean circulation model, ROMS (Regional Ocean Modeling System). By coupling ROMS with a spectral wave model (Simulating Waves Nearshore), we were able to simulate currents within Coral Bay reef‐lagoon system that were in good agreement with the field observations and demonstrate that circulation with the system was wave‐dominated. Both the field measurements and numerical model output confirmed that both residence time (τR) and TA varied primarily with offshore wave heights and location within the bay. However, variations in TA were also affected by the nonlinear interaction between rates of net calcification that varied as a function of diurnally changing light and water residence time that varied as a function of offshore wave heights.
Exceptional melt pond occurrence in the years 2007 and 2011 on the Arctic sea ice revealed from MODIS satellite data
Authors: Rösel Anja , Kaleschke Lars
Published: March 2012

Melt ponds contribute to the ice‐albedo feedback as they reduce the surface albedo of sea ice, and hence accelerate the decay of Arctic sea ice. Here, we analyze the melt pond fraction, retrieved from the MODIS sensor for the years 2000–2011 to characterize the spatial and temporal evolution. A significant anomaly of the relative melt pond fraction at the beginning of the melt season in June 2007 is documented. This is followed by above‐average values throughout the entire summer. In contrast, the increase of the relative melt pond fraction at the beginning of June 2011 is within average values, but from mid‐June, relative melt pond fraction exhibits values up to two standard deviations above the mean values of 30 ± 1.2% which are even higher than in Summer 2007.
Temperature trends at 90 km over Svalbard, Norway (78°N 16°E), seen in one decade of meteor radar observations
Authors: Hall C. M. , Dyrland M. E. , Tsutsumi M. , Mulligan F. J.
Published: March 2012

Temperatures at 90 km altitude above Svalbard (78°N, 16°E) have been determined using a meteor wind radar and subsequently calibrated by satellite measurements for the period autumn 2001 to present. The dependence of the temperatures on solar driving has been investigated using the Ottawa 10.7 cm flux as a proxy. Removing the response of the temperatures to the seasonal and solar cycle variations yields a residual time series which exhibits the negative trend of −4 ± 2 K decade−1. We indicate that, given the month‐to‐month variability and memory in the time series, for a 90% confidence in this trend, we require only 55 months of data – considerably less than the amount available. Cooling of the middle atmosphere, which would be strongly supported by these results, would result in contraction and subsequent lowering of pressure surfaces; we explain that including a negative trend in the pressure model used to obtain temperatures from meteor train echo fading times would also merely serve to augment the observed 90 km cooling.
Evaluation of SMOS retrievals of soil moisture over the central United States with currently available in situ observations
Authors: Collow Thomas W. , Robock Alan , Basara Jeffrey B. , Illston Bradley G.
Published: March 2012

The European Space Agency launched the Soil Moisture Ocean Salinity (SMOS) satellite in November 2009. Using SMOS soil moisture retrievals for 2010 processed using algorithm V4.00, we evaluated SMOS retrievals by comparing them to in situ soil moisture observations for the top 5 cm at several stations in the Great Plains of the U.S. A major issue with comparing the satellite data with in situ data is that a SMOS footprint is about 40 km across and we compare to point observations. To address this issue, we chose locations in Oklahoma that have 10 to 25 different in situ observations within each SMOS footprint. The SMOS retrievals have a dry bias when compared to the average of all in situ stations in a footprint. Large differences exist between the in situ observations, even for probes only a few meters apart. Observations from different sensors within a SMOS footprint differ from each other by a larger amount than they differ from the SMOS retrieval. Removing the mean and normalizing the data bring the in situ observations into better agreement with each other and with SMOS but there are still substantial differences. Agricultural Research Service Micronet regions in Oklahoma had highly varying values of soil moisture despite being in close proximity to one another, but when averaged and compared to SMOS they had less of a bias than the other regions. Further north in the Great Plains, SMOS retrievals of top 5 cm soil moisture from descending orbits were consistently about 5% by volume wetter than ascending retrievals.
Origin of magnetic mineral concentration variation in the Southern Ocean
Authors: Yamazaki Toshitsugu , Ikehara Minoru
Published: March 2012

In the Southern Ocean, magnetic mineral concentration increases in glacial periods. The variation pattern closely resembles eolian dust flux records from Antarctic ice cores, but the cause of the linkage remains unclear, as the dust flux is too small for the source of terrigenous materials in the Southern Ocean. We have conducted an environmental magnetic study of late Pleistocene sediments from the south Indian Ocean to investigate the origin of the magnetic concentration changes. Biogenic magnetites can be detected using the characteristics of almost no magnetostatic interactions and narrow coercivity distribution, reflecting occurrence of single‐domain magnetites in a chain. We interpret that a non‐interacting component on first‐order reversal curve diagrams and low‐coercivity components with small dispersion from isothermal remanent magnetization (IRM) component analyses represent biogenic magnetites, and that the interacting and middle‐coercivity components represent terrigenous maghemites. The ratio of anhysteretic remanent magnetization susceptibility to saturation IRM reflects relative abundance of the biogenic and terrigenous components. It was revealed that biogenic magnetites are a dominant constituent of the magnetic minerals. In glacials, the abundance of both biogenic and terrigenous components increased with increased proportions of the latter. Increased ocean productivity in glacials is suggested from increased proportions of biogenic magnetites with elongated morphologies, indicative of less‐oxic conditions, and increased sedimentation rates. These observations suggest that the increased magnetic concentration in glacials in the Southern Ocean may be explained by iron fertilization; the production of biogenic magnetites was enhanced associated with increased ocean productivity, which was fueled by increased eolian dust flux.
Mechanical versus kinematical shortening reconstructions of the Zagros High Folded Zone (Kurdistan region of Iraq)
Authors: Frehner Marcel , Reif Daniel , Grasemann Bernhard
Published: March 2012

This paper compares kinematical and mechanical techniques for the palinspastic reconstruction of folded cross sections in collision orogens. The studied area and the reconstructed NE–SW trending, 55.5 km long cross section is located in the High Folded Zone of the Zagros fold‐and‐thrust belt in the Kurdistan region of Iraq. The present‐day geometry of the cross section has been constructed from field as well as remote sensing data. In a first step, the structures and the stratigraphy are simplified and summarized in eight units trying to identify the main geometric and mechanical parameters. In a second step, the shortening is kinematically estimated using the dip domain method to 11%–15%. Then the same cross section is used in a numerical finite element model to perform dynamical unfolding simulations taking various rheological parameters into account. The main factor allowing for an efficient dynamic unfolding is the presence of interfacial slip conditions between the mechanically strong units. Other factors, such as Newtonian versus power law viscous rheology or the presence of a basement, affect the numerical simulations much less strongly. If interfacial slip is accounted for, fold amplitudes are reduced efficiently during the dynamical unfolding simulations, while welded layer interfaces lead to unrealistic shortening estimates. It is suggested that interfacial slip and decoupling of the deformation along detachment horizons is an important mechanical parameter that controlled the folding processes in the Zagros High Folded Zone.
Accuracy of scaled GRACE terrestrial water storage estimates
Authors: Landerer F. W. , Swenson S. C.
Published: March 2012

We assess the accuracy of global‐gridded terrestrial water storage (TWS) estimates derived from temporal gravity field variations observed by the Gravity Recovery and Climate Experiment (GRACE) satellites. The TWS data set has been corrected for signal modification due to filtering and truncation. Simulations of terrestrial water storage variations from land‐hydrology models are used to infer relationships between regional time series representing different spatial scales. These relationships, which are independent of the actual GRACE data, are used to extrapolate the GRACE TWS estimates from their effective spatial resolution (length scales of a few hundred kilometers) to finer spatial scales (∼100 km). Gridded, scaled data like these enable users who lack expertise in processing and filtering the standard GRACE spherical harmonic geopotential coefficients to estimate the time series of TWS over arbitrarily shaped regions. In addition, we provide gridded fields of leakage and GRACE measurement errors that allow users to rigorously estimate the associated regional TWS uncertainties. These fields are available for download from the GRACE project website (available at http://grace.jpl.nasa.gov). Three scaling relationships are examined: a single gain factor based on regionally averaged time series, spatially distributed (i.e., gridded) gain factors based on time series at each grid point, and gridded‐gain factors estimated as a function of temporal frequency. While regional gain factors have typically been used in previously published studies, we find that comparable accuracies can be obtained from scaled time series based on gridded gain factors. In regions where different temporal modes of TWS variability have significantly different spatial scales, gain factors based on the first two methods may reduce the accuracy of the scaled time series. In these cases, gain factors estimated separately as a function of frequency may be necessary to achieve accurate results.
Rate‐limited U(VI) desorption during a small‐scale tracer test in a heterogeneous uranium‐contaminated aquifer
Authors: Fox Patricia M. , Davis James A. , Hay Michael B. , Conrad Mark E. , Campbell Kate M. , Williams Kenneth H. , Long Philip E.
Published: March 2012

A tracer test was performed at the Rifle Integrated Field Research Challenge site to assess the effect of addition of bicarbonate on U(VI) desorption from contaminated sediments in the aquifer and to compare equilibrium and rate‐limited reactive transport model descriptions of mass transfer limitations on desorption. The tracer test consisted of injection of a 37 mM NaHCO3solution containing conservative tracers followed by down‐gradient sampling of groundwater at various elevations and distances from the point of injection. Breakthrough curves show that dissolved U(VI) concentrations increased 1.2–2.6‐fold above background levels, resulting from increases in bicarbonate alkalinity (from injectate solution) and Ca concentrations (from cation exchange). In general, more U(VI) was mobilized in shallower zones of the aquifer, where finer‐grained sediments and higher solid phase U content were found compared to deeper zones. An equilibrium‐based reactive transport model incorporating a laboratory‐based surface complexation model derived from the same location predicted the general trends in dissolved U(VI) during the tracer test but greatly overpredicted the concentrations of U(VI), indicating that the system was not at equilibrium. Inclusion of a multirate mass transfer model successfully simulated the nonequilibrium desorption behavior of U(VI). Local sediment properties such as sediment texture (weight percent <2 mm), surface area, cation exchange capacity, and adsorbed U(VI) were heterogeneous at the meter scale, and it was important to incorporate these values into model parameters in order to produce accurate simulations.
Remote triggered seismicity caused by the 2011, M9.0 Tohoku‐Oki, Japan earthquake
Authors: Gonzalez‐Huizar Hector , Velasco Aaron A. , Peng Zhigang , Castro Raul R.
Published: March 2012

Seismic waves from large earthquakes have been shown to trigger seismicity large distances from a mainshock, and this is termed remotely or dynamically triggered seismicity. We performed a global search for seismicity potentially triggered by the seismic waves from the 2011, M9.0, Tohoku‐Oki, Japan Earthquake. Using seismograms from global seismic networks and an event catalog, we search for earthquakes and tremors instantaneously triggered during the passing of the seismic waves, as well as for statistically significant changes in local and global seismic rates after the passing of the waves. For earthquakes, we find potential cases of instantaneous triggering in the United States, Russia, China, Ecuador and Mexico, while for tremors we find evidence for triggering in Taiwan, Armenia, Cuba and the United States. In addition, we observed a potential case of delayed triggering of larger magnitude earthquakes (including a M5.2) in Baja California, Mexico.
Strong radiative heating due to wintertime black carbon aerosols in the Brahmaputra River Valley
Authors: Chakrabarty Rajan K. , Garro Mark A. , Wilcox Eric M. , Moosmüller Hans
Published: March 2012

The Brahmaputra River Valley (BRV) of Southeast Asia recently has been experiencing extreme regional climate change. A week‐long study using a micro‐Aethalometer was conducted during January–February 2011 to measure black carbon (BC) aerosol mass concentrations in Guwahati (India), the largest city in the BRV region. Daily median values of BC mass concentration were 9–41μgm−3, with maxima over 50 μgm−3during evenings and early mornings. Median BC concentrations were higher than in mega cities of India and China, and significantly higher than in urban locations of Europe and USA. The corresponding mean cloud‐free aerosol radiative forcing is −63.4 Wm−2 at the surface and +11.1 Wm−2at the top of the atmosphere with the difference giving the net atmospheric BC solar absorption, which translates to a lower atmospheric heating rate of ∼2 K/d. Potential regional climatic impacts associated with large surface cooling and high lower‐atmospheric heating are discussed.
Probabilistic projections of agro‐climate indices in North America
Authors: Terando Adam , Keller Klaus , Easterling William E.
Published: March 2012

We develop probabilistic projections for three agro‐climate indices (frost days, thermal time, and a heat stress index) for North America. The selected indices are important for understanding the potential impacts of future anthropogenic climate change on agricultural production. We use Bayesian Model Averaging (BMA) and bootstrapping to quantify the structural uncertainty in an ensemble of downscaled General Circulation Models (GCMs). The prior information contained in the observations and model hindcasts is used to construct physically meaningful temporal comparisons for the period 1961–2010. The comparisons are used to derive model‐specific posterior weights to construct probabilistic projections of agro‐climate change in the 21st century. A cross validation test covering the most recent 25 years of the observation period indicates considerable overconfidence in the projections when using the calibrated BMA approach. In contrast the probabilistic projections using equally weighted climate models are not overconfident. The strong consensus among the probabilistic projections that shows warming effects for all three agro‐climate indices is tempered by the short 50‐year calibration period and the small ensemble size. The short calibration period provides a relatively poor observational constraint on estimates of model weights and predictive variance, while the small ensemble size limits the climate sample space. However, the consensus that emerges in spite of the large uncertainties suggests large potential changes in the conditions that farmers will experience over the remainder of the 21st century. Of particular concern is the projected increase in the heat stress index which could lead to large crop damages and associated yield declines.
Biodegradable Luminescent Silicon Quantum Dots for Two Photon Imaging Applications
Authors: Tien Chen-An , Erogbogbo Folarin , Chang Ching-Wen , Adjei-Baffour Priscilla , Law Wing-Chueng , Swihart Mark
Published: March 2012

Cadmium- and lead-based quantum dots are normally coated for biological applications, because their degradation may result in the release of toxic heavy metal ions. Here, we synthesize silicon quantum dots that are expected to biodegrade to non-toxic products. A chitosan coating is used to render the silicon quantum dots stable in storage conditions and biodegradable at physiological conditions. The applications of these particles are demonstrated in cellular imaging with single and two-photon excitation. These results open the door for a new generation of silicon quantum dots that may have a wide variety of applications derived from the flexibility of chitosan.
Endurance Training Per Se Increases Metabolic Health in Young, Moderately Overweight Men
Authors: Nordby Pernille , Auerbach Pernille L. , Rosenkilde Mads , Kristiansen Lasse , Thomasen Jan R. , Rygaard Lisbeth , Groth Rasmus , Brandt Nina , Helge Jørn W. , Richter Erik A. , Ploug Thorkil , Stallknecht Bente
Published: March 2012

Health benefits of physical activity may depend on a concomitant weight loss. In a randomized, controlled trial, we compared the effects of endurance training with or without weight loss to the effect of weight loss induced by an energy‐reduced diet in 48 sedentary, moderately overweight men who completed a 12‐week intervention program of training (T), energy‐reduced diet (D), training and increased diet (T‐iD), or control (C). An energy deficit of 600 kcal/day was induced by endurance training or diet in T and D and a similar training regimen plus an increased dietary intake of 600 kcal/day defined the T‐iD group. Primary end point was insulin sensitivity as evaluated by HOMA‐IR (mainly reflecting hepatic insulin sensitivity) and hyperinsulinemic, isoglycemic clamps (primarily reflecting peripheral insulin sensitivity). Body mass decreased in T and D by 5.9 ± 0.7 and 5.3 ± 0.7 kg, respectively, whereas T‐iD and C remained weight stable. Total and abdominal fat mass were reduced in an additive manner in the T‐iD, D, and T groups by 1.9 ± 0.3/0.2 ± 0.1, 4.4 ± 0.7/0.5 ± 0.1, and 7.7 ± 0.8/0.9 ± 0.1 kg, respectively. HOMA‐IR was improved in T, D, and T‐iD, whereas insulin‐stimulated glucose clearance and suppression of plasma nonesterified fatty acids (NEFAs) were increased only in the two training groups. Thus, loss of fat mass (diet or training induced) improves hepatic insulin sensitivity, whereas peripheral insulin sensitivity in skeletal muscle and adipose tissue is increased by endurance training only. This demonstrates that endurance training per se increases various metabolic health parameters and that endurance training should preferably always be included in any intervention regimen for improving metabolic health in moderately overweight men.
Ovine PrP transgenic Drosophila show reduced locomotor activity and decreased survival
Authors: Thackray Alana M. , Muhammad Farooq , Zhang Chang , Di Ying , Jahn Thomas R. , Landgraf Matthias , Crowther Damian C. , Evers Jan Felix , Bujdoso Raymond
Published: March 2012

Drosophila have emerged as a model system to study mammalian neurodegenerative diseases. In the present study we have generated Drosophila transgenic for ovine PrP (prion protein) to begin to establish an invertebrate model of ovine prion disease. We generated Drosophila transgenic for polymorphic variants of ovine PrP by PhiC31 site-specific germ-line transformation under expression control by the bi-partite GAL4/UAS (upstream activating sequence) system. Site-specific transgene insertion in the fly genome allowed us to test the hypothesis that single amino acid codon changes in ovine PrP modulate prion protein levels and the phenotype of the fly when expressed in the Drosophila nervous system. The Arg154 ovine PrP variants showed higher levels of PrP expression in neuronal cell bodies and insoluble PrP conformer than did His154 variants. High levels of ovine PrP expression in Drosophila were associated with phenotypic effects, including reduced locomotor activity and decreased survival. Significantly, the present study highlights a critical role for helix-1 in the formation of distinct conformers of ovine PrP, since expression of His154 variants were associated with decreased survival in the absence of high levels of PrP accumulation. Collectively, the present study shows that variants of the ovine PrP are associated with different spontaneous detrimental effects in ovine PrP transgenic Drosophila.
A hybrid magnetic/complementary metal oxide semiconductor process design kit for the design of low-power non-volatile logic circuits
Authors: Di Pendina G. , Prenat G. , Dieny B. , Torki K.
Published: March 2012

Since the advent of the MOS transistor, the performance of microelectronic circuits has followed Moore’s law, stating that their speed and density would double every 18 months. Today, this trend tends to get out of breath: the continuously decreasing size of devices and increasing operation frequency result in power consumption and heating issues. Among the solutions investigated to circumvent these limitations, the use of non-volatile devices appears particularly promising. It allows easing, for example, the power gating technique, which consists in cutting-off the power supply of inactive blocks without losing information, drastically reducing the standby power consumption. In this approach, the advantages of magnetic tunnel junctions (MTJs) compared with other non-volatile devices allow one to design hybrid CMOS/magnetic circuits with high performance and new functionalities. Designing such circuits requires integrating MTJs in standard microelectronics design suites. This is performed by means of a process design kit (PDK) for the hybrid CMOS/magnetic technology. We present here a full magnetic PDK, which contains a compact model of the MTJ for electrical simulation, technology files for layout and physical verifications, and standard cells for the design of complex logic circuits and which is compatible with standard design suites. This PDK allows designers to accurately and comfortably design high-performance hybrid CMOS/magnetic logic circuits in the same way as standard CMOS circuits.
Determination of exciton diffusion lengths in isotopically engineered diamond junctions
Authors: Barjon J. , Jomard F. , Tallaire A. , Achard J. , Silva F.
Published: March 2012

A direct observation of exciton diffusion in isotopically engineered 12C/13C diamond junctions is presented. Excitons generated under a focused electron beam in the higher-energy bandgap 13C diamond diffuse and part of them are collected in the lower-energy bandgap 12C diamond, where they recombine. By using cathodoluminescence spectroscopy on samples in cross-section, the recombination intensity is followed as a function of the electron-beam distance to the 12C/13C interface. Exciton diffusion lengths in 13C diamond up to 7.9 µm at 10 K are deduced.