bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of modified techniques of transcatheter closure in large atrial septal defects (⩾30 mm) with anatomic complexities
Authors: Ananthakrishna Pillai Ajith , Upadhyay Amarnath , Gousy Saranya , Handa Amit 
Published: July 2018

AbstractObjectiveThe outcome of transcatheter closure in ostium secundum atrial septal defects is determined by the morphology of the defects. Modified techniques such as balloon assistance, pulmonary vein deployment, left atrial roof technique, and so on are used for circumventing the anatomic complexities and increasing the success rates.MethodsWe planned a prospective study looking at the outcomes of transcatheter closure in secundum atrial septal defects with modified techniques in different anatomic complexities identified in transoesophageal echocardiography and their association with outcome of transcatheter closure.ResultsTranscatheter closure was successful in 295 out of 346 (82%) patients with modified techniques. Balloon-assisted technique offered a success rate of 87%. The mean defect size was 34.7±2.78 mm (95% confidence interval (CI) 30.67–43.1 mm) with success and 40.16±4.5 mm (95% CI 32.16–44.7) with failure (p = 0.02). The mean total septal length was 38.11±0.63 (95% CI 35.21–40.56 mm) with success and 42.54±0.34 (95% CI 38.79–43.21 mm) with failure. The defect to septal ratios were 0.82 and 0.94 in success and failure groups, respectively (p=0.02). However, the absence of a retro-aortic margin, septal aneurysm, and multiple defects did not affect the success rate. Deficient inferior vena caval margin, deficient posterior margin, and size⩾40 mm had a high risk of failure with transcatheter closure. The odds ratio for procedural failure was 25.3 (4.3–143.8) in patients with malaligned septum, 8.3(1.4–48.5) with deficient inferior vena caval margin, and 4.1(2.5–19) for size⩾40 mm.ConclusionsThe modified techniques for device deployment offer substantial chances of success in transcatheter closure of secundum atrial septal defects with anatomical complexity (82%). Variants such as defect size of⩾40 mm and deficient inferior and posterior margins have high failure rates with a modified technique.
Quality assurance of intensity-modulated radiotherapy treatment planning: a dosimetric comparison
Authors: Altaf Saima , Iqbal Khalid , Akram Muhammad , Buzdar Saeed A. 
Published: July 2018

AbstractAimThe purpose of this study was to analyse the comparison of intensity-modulated radiation therapy quality assurance (IMRT QA) using Gafchromic® EBT3 film, Electronic portal imaging device (EPID) and MapCHECK®2.BackgroundPretreatment authentication is the main apprehension in advanced radiation therapy treatment plans such as IMRT.Materials and methodsA total of 20 patients were planned on Eclipse treatment planning system using 6 and 15 MV separately.ResultsGamma index of EBT3 film results shows the following average passing rates: 97% for 6 MV and 96·6% for 15 MV using criteria of ±5% of 3 mm, ±3% of 3 mm and ±3% of 2 mm for brain. However, by using ±5% of 3 mm and ±3% of 3 mm criteria, the average passing rates were 95·4% on 6 MV and 95·2% on 15 MV for prostate. For EPID, the results show the average passing rates as 97·8% for 6 MV and 97·2% for 15 MV in for brain. In cases in which ±5% of 3 mm and ±3% of 3 mm were used, the average passing rates were 96·6% for 6 MVand 96·1% for 15 MV for prostate. MapCHECK®2 results show average passing rates of 96·4% for 6 and 96·2% for 15 MV, respectively, for brain using criteria of ±5% of 3 mm, ±3% of 3 mm and ±3% of 2 mm, whereas for ±5% of 3 mm and ±3% of 3 mm the average rates are 95·2% for 6 and 94·7% for 15 MV in prostate.ConclusionsThe EPID results are better than the other methods, and hence EPID can be used effectively for IMRT pretreatment verifications.
Storm Impact on Morphological Evolution of a Sandy Inlet
Authors: Hopkins Julia , Elgar Steve , Raubenheimer Britt 
Published: July 2018

AbstractObservations of waves, currents, and bathymetric change in shallow water (<10‐m depth) both inside and offshore of a migrating inlet with strong (2–3 m/s) tidal currents and complex nearshore bathymetry show over 2.5 m of erosion and accretion resulting from each of two hurricanes (offshore wave heights >8 m). A numerical model (Delft3D, 2DH mode) simulating waves, currents, and morphological change reproduces the observations with the inclusion of hurricane force winds and sediment transport parameters adjusted based on model‐data comparisons. For simulations of short hurricanes and longer nor'easters with identical offshore total time‐integrated wave energy, but different peak wave energies and storm durations, morphological change is correlated (R2 = 0.60) with storm intensity (total energy of the storm divided by the duration of the storm). Similarly, the erosion observed at the Sand Engine in the Netherlands is correlated with storm intensity. The observations and simulations suggest that the temporal distribution of energy in a storm event, as well as the total energy, impacts subsequent nearshore morphological change. Increased storm intensity enhances sediment transport in bathymetrically complex, mixed wave‐and‐tidal‐current energy environments, as well as at other wave‐dominated sandy beaches.
Thermal Regime and Properties of Soils and Ice‐Rich Permafrost in Beacon Valley, Antarctica
Authors: Liu Lu , Sletten Ronald S. , Hallet Bernard , Waddington Edwin D. 
Published: July 2018

AbstractSubsurface temperatures in polar environments control geomorphic, hydrologic, and biologic processes and ground ice stability. Most studies of the thermal regime in permafrost areas have been developed for the Arctic where interest and concern focus on permafrost thawing. In contrast, this study focuses on soils in the McMurdo Dry Valleys of Antarctica where conditions are much colder and drier, and long‐term persistence of ground ice is of interest including as an analog site for Mars. The soil temperature in Beacon Valley, one of the McMurdo Dry Valleys, has been modeled using the surface temperature, measured heat capacity, and temperature‐dependent thermal conductivity and compared to continuous, high‐resolution measurements of temperatures for a decade down to 19.6‐m depth. For the temperature range of −47.9 to 7.5 °C at our study site, the heat capacity of the dry soil ranges from 580 to 690 J · kg−1 · K−1, thermal conductivity from 0.22 to 0.27 W · m−1 · K−1, and the calculated thermal diffusivity from 0.23 to 0.25 mm2/s. Both the finite difference method and the finite volume method are used to solve the 1‐D heat diffusion equation; the finite volume method‐modeled temperature most closely approximates the measured temperature at all depths with average differences ranging from 0.01 to 0.03 °C. The latent heat contribution of documented episodic snowmelt events and of modeled changes in ice content due to condensation or sublimation is negligible. This study can be applied readily to thermal regimes of similar systems where subsurface temperature measurements are not available such as on Mars.
Estimating Snow Mass in North America Through Assimilation of Advanced Microwave Scanning Radiometer Brightness Temperature Observations Using the Catchment Land Surface Model and Support Vector Machines
Authors: Xue Yuan , Forman Barton A. , Reichle Rolf H. 
Published: July 2018

AbstractTo estimate snow mass across North America, brightness temperature observations collected by the Advanced Microwave Scanning Radiometer (AMSR‐E) from 2002 to 2011 were assimilated into the Catchment model using a support vector machine as the observation operator and a one‐dimensional ensemble Kalman filter. The performance of the assimilation system is evaluated through comparisons against ground‐based measurements and reference snow products. In general, there are no statistically significant skill differences between the domain‐averaged, model‐only (open loop, or OL) snow estimates and assimilation estimates. The assessment of improvements (or degradations) in snow estimates is difficult because of limitations in the measurements (or products) used for evaluation. It is found that assimilation estimates agree slightly better in terms of root‐mean‐square error and Nash‐Sutcliffe model efficiency with ground‐based snow depth measurements than OL estimates in 82% (56 out of 62) of pixels that are colocated with at least two ground‐based stations. Assimilation estimates tend to agree slightly better in terms of mean difference with reference snow products over tundra snow, alpine snow, maritime snow, and sparsely vegetated, snow‐covered pixels. Changes in snow mass via assimilation translate into improvements (e.g., by 22% on average in terms of root‐mean‐square error, relative to OL) in cumulative runoff estimates when compared against discharge measurements in 11 out of 13 snow‐dominated basins in Alaska. These results suggest that a support vector machine can potentially serve as an effective observation operator for snow mass estimation within a radiance assimilation system, but a better observational baseline is required to document a statistically significant improvement.
Estimating the Decoupling Degree of Subtropical Marine Stratocumulus Decks From Satellite
Authors: Zheng Youtong , Rosenfeld Daniel , Li Zhanqing 
Published: July 2018

AbstractsThe decoupling degree of stratocumulus (Sc) decks is an important quantity dictating evolutions of Sc. In subtropical oceans, the Sc decoupling is a key intermediate process of the Sc‐to‐cumulus transitions, a persistent phenomenon that is not fully understood. This study introduces a new approach for estimating the degree of decoupling of subtropical Sc decks using passive satellite sensors. This method is limited to regions where Sc decks are advected over progressively warmer water. This is most common in the subtropics. The estimation concept is that decoupled Sc clouds under cold‐advection conditions are fed by spreading of the tops of cumulus clouds that are coupled. The cumulus clouds constitute a much larger liquid water path over small areas, which is identified by a positive skewness of the liquid water path, a quantity measurable from high‐resolution satellite data. The decoupling degree here is defined as the difference between the Sc cloud‐base height and lifting condensation level that is the cumulus cloud‐base height under cold‐advection conditions. This concept and the satellite‐based estimations are supported by ship measurements over the Northeast Pacific. One‐year climatology of the satellite‐inferred decoupling degree was generated over the same region, revealing a coherent pattern of offshore decoupling, consistent with previous theory and field‐campaign observations.
High‐Latitude Westward Jets in the Earth's Outer Core Due to Small‐Scale Convection
Authors: Afanasyev Y. D. 
Published: July 2018

AbstractThe general circulation of the Earth's outer core is driven by small‐scale convection. A model based on the dynamics of individual buoyant parcels is put forward to explain how the main features of the circulation are generated by the convection. The model predicts a distribution of buoyancy in the core such that the fluid is lighter/warmer at the poles and heavier/colder at the equator. Zonal velocity as a function of latitude is predicted by the model and compared with the previous observational data inferred from the variations of the Earth's magnetic field. The model demonstrates that the westward jets observed at the co‐latitude of approximately 210 are in a geostrophic balance with the dynamic pressure created by convecting parcels and with the excess hydrostatic pressure due to the redistribution of buoyancy in the meridional direction.
On the Role of Heterogeneous Chemistry in Ozone Depletion and Recovery
Authors: Wilka Catherine , Shah Kasturi , Stone Kane , Solomon Susan , Kinnison Douglas , Mills Michael , Schmidt Anja , Neely Ryan R. 
Published: July 2018

AbstractWe demonstrate that identification of stratospheric ozone changes attributable to ozone depleting substances and actions taken under the Montreal Protocol requires evaluation of confounding influences from volcanic eruptions. Using a state‐of‐the‐art chemistry‐climate model, we show that increased stratospheric aerosol loading from volcanic eruptions after 2004 impeded the rate of ozone recovery post‐2000. In contrast, eruptions increased ozone loss rates over the depletion era from 1980 to 1998. We also present calculations without any aerosol chemistry to isolate contributions from gas‐phase chemistry alone. This study reinforces the need for accurate information regarding stratospheric aerosol loading when modeling ozone changes, particularly for the challenging task of accurately identifying the early signs of ozone healing distinct from other sources of variability.
Relative Impacts of Local and Remote Forcing on Tropical Cyclone Frequency in Numerical Model Simulations
Authors: Chang Chuan‐Chieh , Wang Zhuo 
Published: July 2018

AbstractNumerical experiments are carried out to explore the impacts of local and remote forcing on the interannual variability of tropical cyclone (TC) frequency. The first two groups of experiments focus on the regional simulations of Atlantic TCs, and the lateral boundary conditions and sea surface temperature (SST) are specified to investigate the relative importance of remote and local forcing. The results suggest that remote processes outside the North Atlantic, particularly extratropical processes, play an important role in modulating Atlantic TC frequency and that the remote impacts may exceed the impacts of local SST in some years. The total TC frequency in the northern tropics is explored in the third group of experiments. In contrast to the North Atlantic, tropical SST plays a dominant role in modulating the total TC frequency in the northern tropics. The difference may help to explain the uncertainties in the projections of future Atlantic TC frequency.
The Largest Electron Differential Energy Flux Observed at Mars by the Mars Express Spacecraft, 2004–2016
Authors: Frahm R. A. , Winningham J. D. , Coates A. J. , Gérard J.‐C. , Holmström M. , Barabash S. 
Published: July 2018

AbstractThe goal of this paper is to understand the processes by which solar wind electrons are energized in the Martian magnetosphere and how this compares to processes at Venus and Earth. Each is unique in the source of its magnetic field topology and how this influences electron energization. To achieve this goal, 24 million spectra spanning 13 years have been examined using the electron spectrometer from the Mars Express spacecraft between about 12,000 km and about 250 km altitude, and from all latitudes and local times. The top 10 largest differential energy flux at energies above the differential energy flux peak have been found: seven spectra from the magnetosheath near noon, three from the dark tail (the largest two from the middle and ionospheric edge of the magnetosheath). Spectral comparisons show a decade range in the peak of the electron distributions; however, all distributions show a similar energy maximum dictated by solar wind/planet interaction. Similarly derived, the largest Venus spectrum occurred near the magnetosheath bow shock and had the same shape as the most intense Mars inner magnetosheath spectrum. The Mars and Venus dayside spectra compared to the Mars nightside spectrum that included an enhanced optical signal attributed to discrete “auroral” precipitation show a similar shape. These spectra are also compared to a selected auroral zone electron spectra from the Earth. The Mars and Venus results suggest that there is no more energy needed to generate electrons forming the nightside precipitation than is gained during the solar wind/planet interaction.
Structure and Transport of the North Atlantic Current in the Eastern Subpolar Gyre From Sustained Glider Observations
Authors: Houpert L. , Inall M. E. , Dumont E. , Gary S. , Johnson C. , Porter M. , Johns W. E. , Cunningham S. A. 
Published: July 2018

AbstractRepeat glider sections obtained during 2014–2016, as part of the Overturning in the Subpolar North Atlantic Program, are used to quantify the circulation and transport of North Atlantic Current (NAC) branches over the Rockall Plateau. Using 16 glider sections collected along 58°N and between 21°W and 15°W, absolute geostrophic velocities are calculated, and subsequently the horizontal and vertical structure of the transport are characterized. The annual mean northward transport (± standard deviation) is 5.1 ± 3.2 Sv over the Rockall Plateau. During summer (May to October), the mean northward transport is stronger and reaches 6.7 ± 2.6 Sv. This accounts for 43% of the total NAC transport of upper‐ocean waters (σO<27.55 kg/m3) estimated by Sarafanov et al. (2012, https://doi.org/10.1029/2011JC007572) along 59.5°N, between the Reykjanes Ridge and Scotland. Two quasi‐permanent northward flowing branches of the NAC are identified: (i) the Hatton Bank Jet (6.3 ± 2.1 Sv) over the eastern flank of the Iceland Basin (20.5°W to 18.5°W) and (ii) the Rockall Bank Jet (1.5 ± 0.7 Sv) over the eastern flank of the Hatton‐Rockall Basin (16°W to 15°W). Transport associated with the Rockall Bank Jet is mostly depth independent during summer, while 30% of the Hatton Bank Jet transport is due to vertical geostrophic shear. Uncertainties are estimated for each individual glider section using a Monte Carlo approach, and mean uncertainties of the absolute transport are less than 0.5 Sv. Although comparisons with altimetry‐based estimates indicate similar large‐scale circulation patterns, altimetry data do not resolve small mesoscale current bands in the Hatton‐Rockall Basin which are strongly needed for the right transport estimates.
Fingerprinting Sediment Transport in River‐Dominated Margins Using Combined Mineral Magnetic and Radionuclide Methods
Authors: Wang Jinlong , Zhang Weiguo , Baskaran Mark , Du Jinzhou , Zhou Feng , Wu Hui 
Published: July 2018

AbstractBoth magnetic properties and radionuclides are widely used to trace sediment transport in aquatic environments; however, these methods have not been used in combination. In this study, the East China Sea (ECS), a typical river‐dominated margin, was chosen to demonstrate the advantages of combining these two methods to track sediment movements on a seasonal to annual timescale. The ratios between saturation isothermal remnant magnetization and anhysteretic remnant magnetization (χARM/SIRM) and 7Be/210Pbex activity ratios as well as mass balance of 7Be provide information on the seasonal transport of sediment from the Changjiang Estuary to the neighboring shelf. Both 210Pb budget and SIRM distribution in the inner shelf of the ECS show that a small fraction (at most 14% of annual Changjiang sediment discharge) of particles could be transported offshore. Most of 7Be activities in inner shelf sediments of the ECS were below detection limit due to relatively lower residence times and dilution by the older sediment. The observation that radionuclide activities exhibit a better correlation with χARM/SIRM ratios than with grain size suggests that iron oxides are the primary carriers of 7Be, 210Pb, and 234Th. The absorption of radionuclides onto magnetic minerals further reinforces the reliability of this combined approach in tracing sediment transport. Our study indicates that radionuclides, with different half‐lives, can be utilized for quantifying sediment dynamics, whereas magnetic properties can yield more detailed information on sediment transport directions. The combined analysis of magnetic parameters and radionuclides offers a better understanding of sediment transport in river‐dominated areas.
High‐Frequency Geomagnetic Fluctuations at Auroral Oval and Polar Cap
Authors: Peitso P. , Tanskanen E. I. , Pulkkinen T. I. , Mursula K. 
Published: July 2018

AbstractRapid magnetic fluctuations are known to be closely linked to the high‐latitude geomagnetic activity, in particular, to geomagnetic pulsations and subtorms. Increasing amount of commercial activity in the arctic regions requires better monitoring capability and improved understanding on the effects of geomagnetic hazards to infrastructure. In this study, we analyze rapid, 1‐s fluctuations in Greenland. To measure high‐frequency geomagnetic fluctuations in the auroral oval and polar cap, we use high time resolution data of 1 s from 12 stations covering a large latitudinal range of 64 to 84 quasi‐dipole geomagnetic latitude (QDGMlat). We found out that the large magnetic field fluctuations exceeding 0.2 nT/s are observed 10–30% of the time in auroral oval latitudes, depending on the solar cycle phase and station location. The latitudinal differences are much larger in fluctuation coverage (fractional derivative rate, FDR) than in fluctuations amplitude (dH/dt). The highest |dH/dt| and FDRs at noon are observed at the northern stations from 72 to 84 QDGMlat, while in south Greenland from 72 to 65 QDGMlat, the highest |dH/dt| and FDRs are recorded at midnight. The largest differences in seasonal variation between noon and midnight are observed in the polar cap, where a summer increase is seen at noon and almost flat seasonal profile at midnight.
Fn14 deficiency ameliorates psoriasis-like skin disease in a murine model
Authors: Peng L. , Li Q. , Wang H. , Wu J. , Li C. , Liu Y. , Liu J. , Xia L. , Xia Y. 
Published: July 2018

AbstractTumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) is a multifunctional cytokine that acts through its receptor fibroblast growth factor-inducible 14 (Fn14). Recent studies demonstrated that the TWEAK/Fn14 signals participate in the development of psoriasis. The purpose of this study was to further explore the effect of Fn14 inhibition on experimental psoriasis. Psoriasis-like skin disease was induced in the wild-type and Fn14-knockout BALB/c mice. We found that Fn14 deficiency ameliorates psoriasis-like lesion in this model, accompanied by less inflammatory cell infiltration and proinflammatory cytokine production in lesional skin. The cutaneous expression of TNF receptor type 2 also decreased in the Fn14-deficient mice. Moreover, the topical application of TWEAK exacerbated psoriatic lesion in the wild-type but not in the Fn14-deficient mice. Furthermore, TWEAK promoted the expression of interleukin 8, keratin 17, and epidermal growth factor receptor (EGFR) but inhibited the expression of involucrin in psoriatic keratinocytes in vitro. Interestingly, such effect of TWEAK was abrogated by an EGFR inhibitor (erlotinib). TWEAK also enhances the proliferation and interleukin-6 production of dermal microvascular endothelial cells under psoriatic condition. In conclusion, TWEAK/Fn14 signals contribute to the development of psoriasis, and involves the modulation of resident cells and the transduction of the EGFR pathway. Fn14 inhibition might be a novel therapeutic strategy for patients with psoriasis.
Strongly-coupled quantum critical point in an all-in-all-out antiferromagnet
Authors: Wang Yishu , Rosenbaum T. F. , Palmer A. , Ren Y. , Kim J.-W. , Mandrus D. , Feng Yejun 
Published: July 2018

AbstractDimensionality and symmetry play deterministic roles in the laws of Nature. They are important tools to characterize and understand quantum phase transitions, especially in the limit of strong correlations between spin, orbit, charge, and structural degrees of freedom. Here, using newly-developed, high-pressure resonant X-ray magnetic and charge diffraction techniques, we have discovered a quantum critical point in Cd2Os2O7 as the all-in-all-out antiferromagnetic order is continuously suppressed to zero temperature and, concomitantly, the cubic lattice structure continuously changes from space group Fd-3m to F-43m. Surrounded by three phases of different time reversal and spatial inversion symmetries, the quantum critical region anchors two phase lines of opposite curvature, with striking departures from a mean-field form at high pressure. As spin fluctuations, lattice breathing modes, and quasiparticle excitations interact in the quantum critical region, we argue that they present the necessary components for strongly-coupled quantum criticality in this three-dimensional compound.