bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Transient Coupled Ice Flow‐Damage Model to Simulate Iceberg Calving From Tidewater Outlet Glaciers
Authors: Mercenier R. , Lüthi M. P. , Vieli A. 
Published: July 2019

AbstractIceberg calving, the detachment of an ice block at the glacier front, is the main process responsible for the dynamic mass loss from the ice sheets to the ocean. Understanding this process is essential to accurately predict ice sheet response to the future climate. We present a transient multiphysics finite‐element model to simulate iceberg break‐off and geometry evolution of a marine‐terminating glacier. The model solves the coupled equations of ice flow, damage mechanics, oceanic melt, and geometry evolution on the same Lagrangian computational grid. A modeling sensitivity analysis shows that the choice of stress measure used for damage evolution strongly influences the resulting calving front geometries. Our analysis suggests that the von Mises stress measures produce the most realistic calving front geometry evolutions for tidewater glaciers. Submarine frontal melt is shown to have a strong impact on the calving front geometry. The presented multiphysics model includes all processes thus far shown to be relevant for the evolution of tidewater glaciers and can be readily adapted for 3‐D and arbitrary bedrock geometries.
River Bathymetry Estimate and Discharge Assessment from Remote Sensing
Authors: Moramarco Tommaso , Barbetta Silvia , Bjerklie David M. , Fulton John W. , Tarpanelli Angelica 
Published: July 2019

AbstractThe NASA Surface Water Ocean Topography (SWOT) mission and ESA Sentinel‐1, inter‐alia, propose to monitor inland waters from satellites. The radar altimeter and the microwave radiometer can be used to monitor water surface level and assess the cross‐sectional mean flow velocity, respectively. However, for most river sites bathymetric data are lacking, preventing the direct computation of discharge. In this context, a new methodology for simulating the bathymetry and estimating the discharge is proposed. The approach is based on entropy theory and can be applied using ground and satellite observations. Four parameters are needed and include channel roughness, water surface slope, channel bottom elevation, and an entropy parameter of flow depth. These parameters are estimated using a genetic algorithm by minimizing the error in the observed maximum surface velocity. Parameter uncertainty is considered through 1,000 random realizations based on different initial values. Eighteen streamflow measurements recorded from three different gauged river sites are used to benchmark the ground observations. The method included ENVISAT altimetry and Moderate Resolution Imaging Spectroradiometer (MODIS) data (2002‐2010) at one river site. Relative to ground measurements, the method provides good results with an error in channel area and discharge that, on average, does not exceed 10% on the 50th percentile. Relative to satellite measurements, channel area is well simulated with an error, on average, lower than 9%; discharge is less well simulated and represented by an error greater than 30% on the 50th percentile.
Shoreline Slope Breaks Revise Understanding of Hawaiian Shield Volcanoes Evolution
Authors: Taylor Brian 
Published: July 2019

AbstractSlope gradient maps of swath bathymetry around the Hawaiian islands locate 12 shield slope breaks associated with former shorelines that are now submerged, ranging in age back to 5 Ma. The age of their drowning correlates with the waning of tholeiitic shield volcanism that ceases to repave the shoreline sometime between the beginning and the end of the late‐shield stage. Slope breaks on Mauna Loa's northeast and southwest rifts are consistent with it being in the waning stages of shield building. Superposition of shorebreaks shows that the Hualālai shield is older than Mauna Kea's. We find evidence for three volcanic shields forming Ka'ena Ridge, for a simultaneous waning of Maui‐Lāna'i‐Kaho'olawe shield building and the initiation of Kohala shield building by 1.3 Ma, and for Mahukona growing to just above sea level about 0.6 Ma. A contiguous shoreline slope break formed ~1.8 Ma at the end of the West Moloka'i late‐shield stage and the beginning of the East Moloka'i late‐shield stage. At its western end the shield dips obliquely away from, rather than toward, this slope break. Similarly, the short Hualālai slope break plunges north, which is opposite to that expected for volcanic loading to the south. Shields locally sloping away from paleoshorelines may be related to landslides causing flexural back tilting away from their unloaded footwall. The Nu'uanu and Wailau slides and Pololū slump were mostly shield flank events that cut marginally into their former shorelines, enough to preferentially nucleate headward erosion by streams.
Varying Sensitivity of East Asia Summer Monsoon Circulation to Temperature Change Since Last Glacial Maximum
Authors: Cheng Jun , Ma Wuyang , Liu Zhengyu , Wu Haibin 
Published: July 2019

AbstractProxy records of the East Asia summer monsoon (EASM) and temperature reveal an in‐phase relationship of the two since the Last Glacial Maximum (LGM), which is consistent with their expected physical relationship; but the response amplitude of EASM to temperature variation seemed larger over the Holocene than over the last deglaciation. Using a state‐of‐the‐art transient climate simulation, we confirm this proxy‐inferred phenomenon, and estimate the “sensitivity of EASM circulation to summer temperature over adjacent region” (defined as SMT here) is about five times over the Holocene of that over the last deglaciation. This varying SMT attributed to the diverse SMT under the solo forcing of orbital insolation and CO2 (eight times of the former vs. the latter), and their varying confounding effect along time. The results presented here should improve our understanding of the past change of EASM, and help project its variation magnitude under ongoing CO2‐forced global warming.
The Effects of Solar Wind Dynamic Pressure on the Structure of the Topside Ionosphere of Mars
Authors: Girazian Z. , Halekas J. , Morgan D. D. , Kopf A. J. , Gurnett D. A. , Chu F. 
Published: July 2019

AbstractWe use Mars Atmosphere and Volatile EvolutioN observations of the upstream solar wind, and Mars Express observations of ionospheric electron densities and magnetic fields, to study how the topside ionosphere (>320 km) of Mars is affected by variations in solar wind dynamic pressure. We find that high solar wind dynamic pressures result in the topside ionosphere being depleted of plasma at all solar zenith angles, coincident with increased induced magnetic field strengths. The depletion of topside plasma in response to high solar wind dynamic pressures is observed in both weak and strong crustal magnetic field regions. Taken together, our results suggest that high solar wind dynamic pressures lead to ionospheric compression, increased ion escape, and reduced day‐to‐night plasma transport in the high‐altitude nightside ionosphere.
Continent‐Wide, Interferometric SAR Phase, Mapping of Antarctic Ice Velocity
Authors: Mouginot J. , Rignot E. , Scheuchl B. 
Published: July 2019

AbstractSurface ice velocity is a fundamental characteristic of glaciers and ice sheets that quantifies the transport of ice. Changes in ice dynamics have a major impact on ice sheet mass balance and its contribution to sea level rise. Prior comprehensive mappings employed speckle and feature tracking techniques, optimized for fast‐flow areas, with precision of 2‐5 m/year, hence limiting our ability to describe ice flow in the slow interior. We present a vector map of ice velocity using the interferometric phase from multiple satellite synthetic aperture radars resulting in 10 times higher precision in speed (20 cm/year) and direction (5°) over 80% of Antarctica. Precision mapping over areas of slow motion (<1 m/year) improves from 20 to 93%, which helps better constrain drainage boundaries, improve mass balance assessment, evaluate regional atmospheric climate models, reconstruct ice thickness, and inform ice sheet numerical models.
Western Mediterranean Climate Response to Dansgaard/Oeschger Events: New Insights From Speleothem Records
Authors: Budsky Alexander , Wassenburg Jasper A. , Mertz‐Kraus Regina , Spötl Christoph , Jochum Klaus Peter , Gibert Luis , Scholz Denis 
Published: July 2019

AbstractThe climate of the western Mediterranean was characterized by a strong precipitation gradient during the Holocene driven by atmospheric circulation patterns. The scarcity of terrestrial paleoclimate archives has precluded exploring this hydroclimate pattern during Marine Isotope Stages 5 to 3. Here we present stable carbon and oxygen isotope records from three flowstones from southeast Iberia, which show that Dansgaard/Oeschger events were associated with more humid conditions. This is in agreement with other records from the Iberian Peninsula, the Mediterranean, and western Europe, which all responded in a similar way to millennial‐scale climate variability in Greenland. This general increase in precipitation during Dansgaard/Oeschger events cannot be explained by any present‐day or Holocene winter atmospheric circulation pattern. Instead, we suggest that changes in sea surface temperature played a dominant role in determining precipitation amounts in the western Mediterranean.
Spatially Extended Tests of a Neural Network Parametrization Trained by Coarse‐Graining
Authors: Brenowitz Noah D. , Bretherton Christopher S. 
Published: July 2019

AbstractGeneral circulation models (GCMs) typically have a grid size of 25–200 km. Parametrizations are used to represent diabatic processes such as radiative transfer and cloud microphysics and account for subgrid‐scale motions and variability. Unlike traditional approaches, neural networks (NNs) can readily exploit recent observational data sets and global cloud‐system resolving model (CRM) simulations to learn subgrid variability. This article describes an NN parametrization trained by coarse‐graining a near‐global CRM simulation with a 4‐km horizontal grid spacing. The NN predicts the residual heating and moistening averaged over (160 km)2 grid boxes as a function of the coarse‐resolution fields within the same atmospheric column. This NN is coupled to the dynamical core of a GCM with the same 160‐km resolution. A recent study described how to train such an NN to be stable when coupled to specified time‐evolving advective forcings in a single‐column model, but feedbacks between NN and GCM components cause spatially extended simulations to crash within a few days. Analyzing the linearized response of such an NN reveals that it learns to exploit a strong synchrony between precipitation and the atmospheric state above 10 km. Removing these variables from the NN's inputs stabilizes the coupled simulations, which predict the future state more accurately than a coarse‐resolution simulation without any parametrizations of subgrid‐scale variability, although the mean state slowly drifts.
Submesoscale Impacts on Mesoscale Agulhas Dynamics
Authors: Schubert R. , Schwarzkopf F. U. , Baschek B. , Biastoch A. 
Published: July 2019

AbstractMesoscale dynamics of the Agulhas Current system determine the exchange between the Indian and Atlantic oceans, thereby influencing the global overturning circulation. Using a series of ocean model experiments compared to observations, we show that the representation of mesoscale eddies in the Agulhas ring path improves with increasing resolution of submesoscale flows. Simulated submesoscale dynamics are validated with time‐mean horizontal‐wavenumber spectra from satellite sea surface temperature measurements and mesoscale dynamics with spectra from sea surface height. While the Agulhas ring path in a nonsubmesoscale‐resolving (1/20)° configuration is associated with too less power spectral densities on all scales and too steep spectral slopes, the representation of the mesoscale dynamics improves when the diffusion and the dissipation of the model are reduced and some small‐scale features are resolved. Realistic power spectral densities over all scales are achieved when additionally the horizontal resolution is increased to (1/60)° and a larger portion of the submesoscale spectrum is resolved. Results of an eddy detection algorithm applied to the model outputs as well as to a gridded sea surface height satellite product show that in particular strong cyclones are much better represented when submesoscale flows are resolved by the model. The validation of the submesoscale dynamics with sea surface temperature spectra provides guidance for the choice of advection schemes and explicit diffusion and dissipation as well as for further subgrid‐scale parameterizations. For the Agulhas ring path, the use of upstream biased advection schemes without explicit diffusion and dissipation is found to be associated with realistically simulated submesoscales.
Surface acoustic wave humidity sensors based on uniform and thickness controllable graphene oxide thin films formed by surface tension
Authors: Le Xianhao , Liu Yihan , Peng Li , Pang Jintao , Xu Zhen , Gao Chao , Xie Jin 
Published: July 2019

AbstractGraphene oxide (GO) is a promising candidate for humidity sensing, and the uniformity and thickness of GO films are important for the reproducibility and test signal strength of humidity sensors. In this paper, uniform and thickness-controllable GO films are first formed by the surface tension of different concentrations of GO solution and then transferred to surface acoustic wave (SAW) humidity sensors. This GO film formation and transfer process has very good repeatability and stability, as evidenced by the humidity response of the sensors. With the help of the uniform and highly oxidized GO film, the humidity sensors show a significantly high sensitivity (absolute sensitivity of 25.3 kHz/%RH and relative sensitivity of 111.7 p.p.m./%RH) in a wide test range from 10%RH to 90%RH with very little hysteresis (<1%RH). The sensors achieve good reversibility, excellent short-term repeatability and stability. Moreover, the humidity sensors also show a fast response and recovery time of <10 s.
Altered white matter microstructure in 22q11.2 deletion syndrome: a multisite diffusion tensor imaging study
Authors: Villalón-Reina Julio E. , Martínez Kenia , Qu Xiaoping , Ching Christopher R. K. , Nir Talia M. , Kothapalli Deydeep , Corbin Conor , Sun Daqiang , Lin Amy , Forsyth Jennifer K. , Kushan Leila , Vajdi Ariana , Jalbrzikowski Maria , Hansen Laura , Jonas Rachel K. , van Amelsvoort Therese , Bakker Geor , Kates Wendy R. , Antshel Kevin M. , Fremont Wanda , Campbell Linda E. , McCabe Kathryn L. , Daly Eileen , Gudbrandsen Maria , Murphy Clodagh M. , Murphy Declan , Craig Michael , Emanuel Beverly , McDonald-McGinn Donna M. , Vorstman Jacob A.S. , Fiksinski Ania M. , Koops Sanne , Ruparel Kosha , Roalf David , Gur Raquel E. , Eric Schmitt J. , Simon Tony J. , Goodrich-Hunsaker Naomi J. , Durdle Courtney A. , Doherty Joanne L. , Cunningham Adam C. , van den Bree Marianne , Linden David E. J. , Owen Michael , Moss Hayley , Kelly Sinead , Donohoe Gary , Murphy Kieran C. , Arango Celso , Jahanshad Neda , Thompson Paul M. , Bearden Carrie E. 
Published: July 2019

Abstract22q11.2 deletion syndrome (22q11DS)—a neurodevelopmental condition caused by a hemizygous deletion on chromosome 22—is associated with an elevated risk of psychosis and other developmental brain disorders. Prior single-site diffusion magnetic resonance imaging (dMRI) studies have reported altered white matter (WM) microstructure in 22q11DS, but small samples and variable methods have led to contradictory results. Here we present the largest study ever conducted of dMRI-derived measures of WM microstructure in 22q11DS (334 22q11.2 deletion carriers and 260 healthy age- and sex-matched controls; age range 6–52 years). Using harmonization protocols developed by the ENIGMA-DTI working group, we identified widespread reductions in mean, axial and radial diffusivities in 22q11DS, most pronounced in regions with major cortico-cortical and cortico-thalamic fibers: the corona radiata, corpus callosum, superior longitudinal fasciculus, posterior thalamic radiations, and sagittal stratum (Cohen’sd’s ranging from −0.9 to −1.3). Only the posterior limb of the internal capsule (IC), comprised primarily of corticofugal fibers, showed higher axial diffusivity in 22q11DS. 22q11DS patients showed higher mean fractional anisotropy (FA) in callosal and projection fibers (IC and corona radiata) relative to controls, but lower FA than controls in regions with predominantly association fibers. Psychotic illness in 22q11DS was associated with more substantial diffusivity reductions in multiple regions. Overall, these findings indicate large effects of the 22q11.2 deletion on WM microstructure, especially in major cortico-cortical connections. Taken together with findings from animal models, this pattern of abnormalities may reflect disrupted neurogenesis of projection neurons in outer cortical layers.
Modifying PTEN recruitment promotes neuron survival, regeneration, and functional recovery after CNS injury
Authors: Shabanzadeh Alireza Pirsaraei , D’Onofrio Philippe Matteo , Magharious Mark , Choi Kyung An Brian , Monnier Philippe Patrick , Koeberle Paulo Dieter 
Published: July 2019

AbstractPhosphatase and tensin homolog (PTEN) regulates apoptosis and axonal growth in the developing and adult central nervous system (CNS). Here, we show that human PTEN C-terminal PDZ interactions play a critical role in neuronal apoptosis and axon regeneration after traumatic CNS injury and stroke, highlighted by the findings that antagonizing the PDZ-motif interactions of PTEN has therapeutic applicability for these indications. Interestingly, the death-inducing function of PTEN following ischemic insult depends on a PDZ-domain interaction with MAGI-2 and MAST205, PDZ proteins that are known to recruit PTEN to the plasma membrane and stabilize its interaction with PIP3. Treatments with a human peptide that prevents PTEN association with MAGI-2 or MAST205 increased neuronal survival in multiple stroke models, in vitro. A pro-survival effect was also observed in models of retinal ischemia, optic nerve transection, and after middle cerebral artery occlusion (MCAO) in adult rats. The human PTEN peptide also improved axonal regeneration in the crushed optic nerve. Furthermore, human PTEN peptide therapy promoted functional improvement after MCAO or retinal ischemia induced via ophthalmic artery ligation. These findings show that the human peptide-based targeting of C-terminal PTEN PDZ interactions has therapeutic potential for insults of the CNS, including trauma and stroke.
Molecular movie of ultrafast coherent rotational dynamics of OCS
Authors: Karamatskos Evangelos T. , Raabe Sebastian , Mullins Terry , Trabattoni Andrea , Stammer Philipp , Goldsztejn Gildas , Johansen Rasmus R. , Długołecki Karol , Stapelfeldt Henrik , Vrakking Marc J. J. , Trippel Sebastian , Rouzée Arnaud , Küpper Jochen 
Published: July 2019

AbstractRecording molecular movies on ultrafast timescales has been a longstanding goal for unravelling detailed information about molecular dynamics. Here we present the direct experimental recording of very-high-resolution and -fidelity molecular movies over more than one-and-a-half periods of the laser-induced rotational dynamics of carbonylsulfide (OCS) molecules. Utilising the combination of single quantum-state selection and an optimised two-pulse sequence to create a tailored rotational wavepacket, an unprecedented degree of field-free alignment, 〈cos2θ2D〉 = 0.96 (〈cos2θ〉 = 0.94) is achieved, exceeding the theoretical limit for single-pulse alignment. The very rich experimentally observed quantum dynamics is fully recovered by the angular probability distribution obtained from solutions of the time-dependent Schrödinger equation with parameters refined against the experiment. The populations and phases of rotational states in the retrieved time-dependent three-dimensional wavepacket rationalises the observed very high degree of alignment.
A plasmid-encoded peptide from Staphylococcus aureus induces anti-myeloperoxidase nephritogenic autoimmunity
Authors: Ooi Joshua D. , Jiang Jhih-Hang , Eggenhuizen Peter J. , Chua Ling L. , van Timmeren Mirjan , Loh Khai L. , O’Sullivan Kim M. , Gan Poh Y. , Zhong Yong , Tsyganov Kirill , Shochet Lani R. , Ryan Jessica , Stegeman Coen A. , Fugger Lars , Reid Hugh H. , Rossjohn Jamie , Heeringa Peter , Holdsworth Stephen R. , Peleg Anton Y. , Kitching A. Richard 
Published: July 2019

AbstractAutoreactivity to myeloperoxidase (MPO) causes anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), with rapidly progressive glomerulonephritis. Here, we show that a Staphylococcus aureus peptide, homologous to an immunodominant MPO T-cell epitope (MPO409–428), can induce anti-MPO autoimmunity. The peptide (6PGD391–410) is part of a plasmid-encoded 6-phosphogluconate dehydrogenase found in some S. aureus strains. It induces anti-MPO T-cell autoimmunity and MPO-ANCA in mice, whereas related sequences do not. Mice immunized with 6PGD391–410, or with S. aureus containing a plasmid expressing 6PGD391–410, develop glomerulonephritis when MPO is deposited in glomeruli. The peptide induces anti-MPO autoreactivity in the context of three MHC class II allomorphs. Furthermore, we show that 6PGD391–410 is immunogenic in humans, as healthy human and AAV patient sera contain anti-6PGD and anti-6PGD391–410 antibodies. Therefore, our results support the idea that bacterial plasmids might have a function in autoimmune disease.
Photothermal conversion triggered thermal asymmetric catalysis within metal nanoparticles loaded homochiral covalent organic framework
Authors: Ma Hui-Chao , Zhao Chen-Chen , Chen Gong-Jun , Dong Yu-Bin 
Published: July 2019

AbstractFor seeking high enantiopurity, the previously reported thermal asymmetric catalysis is usually carried out at low temperature sometimes with limited yield, that is, the high enantiomeric excess (ee) usually at the cost of high yield. Thus, the achieving both high stereoselectivity and yield is an enormous challenge. We report herein two metal nanoparticle (M NP)-loaded and porphyrin-containing homochiral covalent organic framework (CCOF)-based composite catalysts, and their application in the thermally-driven asymmetric one-pot Henry and A3-coupling reactions. All the reactions are conducted at elevated temperatures with both excellent stereoselectivity and yield which resulted from the synergy of CCOF confinement effect and M NP catalytic activation. Notably, the needed thermal energy for the asymmetric reactions herein is derived from the photothermal conversion via porphyrin-based CCOF upon irradiation with visible light. Remarkably, the CCOF confinement effect can be effectively maintained up to 100 °C for the asymmetric one-pot Henry and A3-coupling reactions herein.