bluuebunny/crossref_metadata_2025 huggingface dataset:
Physical Representation Learning and Parameter Identification from Video Using Differentiable Physics
Authors: Kandukuri Rama Krishna , Achterhold Jan , Moeller Michael , Stueckler Joerg
Published: October 2021

Representation learning for video is increasingly gaining attention in the field of computer vision. For instance, video prediction models enable activity and scene forecasting or vision-based planning and control. In this article, we investigate the combination of differentiable physics and spatial transformers in a deep action conditional video representation network. By this combination our model learns a physically interpretable latent representation and can identify physical parameters. We propose supervised and self-supervised learning methods for our architecture. In experiments, we consider simulated scenarios with pushing, sliding and colliding objects, for which we also analyze the observability of the physical properties. We demonstrate that our network can learn to encode images and identify physical properties like mass and friction from videos and action sequences. We evaluate the accuracy of our training methods, and demonstrate the ability of our method to predict future video frames from input images and actions.
In Vitro Evaluation of Biologically Derived Hydroxyapatite Coatings Manufactured by High Velocity Suspension Spraying
Authors: Blum M. , Sayed M. , Mahmoud E. M. , Killinger A. , Gadow R. , Naga S. M.
Published: October 2021

This investigation aims to study a novel biologically derived coating applied on Ti alloy substrates. Obtained from a low-cost fish bone resource, a nanocrystalline hydroxyapatite has been synthesized and converted to an organic suspension. Coating was then manufactured by a high-velocity suspension flame spray process. The microstructure, phase composition, coating thickness, and roughness of hydroxyapatite (HA)-coated samples were studied. The results indicated the presence of both hydroxyapatite and β-tricalcium phosphate phases and the final coating layer was uniform and dense. In vitro bioactivity and biodegradability of the HA/Ti composite samples were estimated by immersion in simulated body fluid. Remarkable reductions in Ca2+ and PO43− ion concentrations were observed as well as low weight loss percentage and a slight variation in the pH value, indicating the generation of an apatite layer on the surface of all studied samples. Scanning electron microscopy, energy-dispersive x-ray analysis, and inductively coupled plasma–optical emission spectrometry confirm these results. Thus biological derived HA coatings are a promising candidate to enhance bioactivity and biodegradability of bone implants. To demonstrate feasibility on commercial medical components, a medical screw was coated and evaluated.
The effects of increased dopamine-levels on attentional control during reading and reading comprehension
Authors: Swart Elise K. , Sikkema-de Jong Maria T.
Published: October 2021

The aim of the present study was to gain insight into the neurobiological processes, particularly the dopaminergic processes, underlying attentional control during reading and reading comprehension. In order to test the effects of increased levels of dopamine (DA) in the brain, female university students (N = 80), half of them being carriers of the DRD4-7R allele and half of them not, participated in a double-blind placebo-controlled within-subjects experiment in which they were orally administered levodopa or a placebo before reading a text. After reading the text, participants reported on their attentional control during reading and completed comprehension questions. Pharmacologically increasing DA levels in the brain negatively influenced reading comprehension. This effect was moderate (ηp2 = .13). No interaction effects of condition and DRD4 genotype were found, for either attentional control or reading comprehension. Exploratory analyses showed that increased DA levels in the brain positively influenced fluctuations in attentional control, but only in a group of slow readers. No effects of increased DA were found for the two other attentional control measures used in the present study and no effects of increased DA on attentional control were found for fast readers. Results are discussed from the perspective of the inverted U-shape theory and the possible dopamine-related mechanisms.
A Review of the Neoproterozoic Global Glaciations and a Biotic Cause of Them
Authors: Casado Juan
Published: October 2021

In the Neoproterozoic Era, the Earth experienced two broad intervals of global glaciation, commonly known as Snowball Earth. There was also a rapid diversification of life, with the evolution of most of the eukaryotic lineages. Here, salient evidence for the Neoproterozoic global glaciations, including the carbon isotope record, is reinterpreted, and an alternative explanation for the causes of glaciation is proposed. The proliferation of life could have led to increases in atmospheric O2levels and concomitant decreases in CO2and CH4. Coupled biochemical and geochemical changes would have led to global cooling and glaciation. This so-called biotic hypothesis of the Snowball Earth is consistent with the most salient features of the reported evidence and explains the consecutive episodes of global glaciation.
Outpatient antimicrobial stewardship programs in pediatric institutions in 2020: Status, needs, barriers
Authors: El Feghaly Rana E. , Monsees Elizabeth A. , Burns Alaina , Wirtz Ann , Lee Brian R. , Hersh Adam L. , Newland Jason G.
Published: October 2021

Objective:

To assess current resources, interventions, and obstacles of pediatric outpatient antimicrobial stewardship programs (ASP).

Design:

Cross-sectional study.

Setting:

Institutions from the Sharing Antimicrobial Reports for Pediatric Stewardship OutPatient collaborative (SHARPS-OP).

Participants:

Antimicrobial stewardship leaders from the above institutions.

Methods:

An investigator-developed survey was deployed online in September 2020 to antimicrobial stewardship leaders in SHARPS-OP institutions. The survey was divided into 4 sections: (1) basic information, (2) status of pediatric outpatient ASP in the institutions including financial support, (3) outpatient ASP interventions undertaken by the institutions, and (4) needs and SHARPS-OP collaborative goals.

Results:

Of 56 invited institutions, 45 participated, achieving an 80% response rate. Only 5 sites (11%) had allocated financial support for an outpatient ASP, compared to 42 (95.6%) for their inpatient ASP. The most widely used outpatient ASP interventions included antimicrobial guidance (57.8%), education (46.7%), and quality improvement projects (37.8%). Time was identified as the biggest barrier to expanding outpatient ASPs (91.1%), followed by financial support (53.3%), development of meaningful reports (51.1%), and administrative support (44.4%). Important goals of the collaborative included seeking learning opportunities and developing clear metrics for pediatric outpatient ASP benchmarking. Program needs included securing operational support (35.8%) and strengthening data analysis (31.6%).

Conclusions:

Very few pediatric institutions with robust inpatient ASPs have devoted time and financial support to advance outpatient efforts. To promote appropriate antibiotic prescribing in the outpatient arena, time and resource funding by administrative leaders are necessary to develop a robust, sustainable stewardship infrastructure.
Characteristics of Ionospheric Storm on October 13, 2016 at the Greenwich Meridian
Authors: Wan Qingtao , Ma Guanyi , Maruyama Takashi , Li Jinghua , Wang Xiaolan , Lu Weijun
Published: October 2021

An ionospheric positive disturbance during a moderate geomagnetic storm on October 13, 2016 was studied with total electron content (TEC) from a chain of GNSS receivers and F2 layer peak parameters from two ionosondes at the Greenwich meridian. During a slow decrease of Dst, a large enhancement of the daytime TEC was observed from high to middle latitudes successively while there was small disturbance observed in low latitudes. The occurrence of TEC peak delayed with decreasing latitude. Similarly, positive disturbance of hmF2 and foF2 was recorded and their onsets were earlier in high latitude than middle latitude. These observations indicated that the ionospheric positive disturbance propagated equatorward which denied the dominant effect of prompt penetration eastward electric field (PPEF). Using the latitudinal and temporal variations of TEC peaks, the propagation velocity of the disturbance was estimated and found to decrease with decreasing latitude. Two available Fabry‐Perot interferometers (FPI) at the meridian W of the Greenwich showed that nighttime equatorward wind in middle latitude increased significantly after the storm sudden commencement (SSC), while no change of that was observed in low latitude. The coincidence of the directional and latitudinal features between the ionospheric disturbance and the wind observation suggested the impact of the positive storm was most likely the equatorward wind surge which raised the ionosphere to higher altitude where lower chemical loss led to increase of electron density in the daytime.
First High‐Resolution Benthic Habitat Map From the Greenland Shelf (Disko Bay Pilot Study)
Authors: Krawczyk D. W. , Zinglersen K. B. , Al‐Hamdani Z. , Yesson C. , Blicher M. E. , Arboe N. H. , Jensen J. B. , Wagnholt J. N. , Hansen F. , Rödel L.‐G.
Published: October 2021

A healthy ocean where marine habitats and ecosystems are mapped and protected is one of the UN's Sustainable Development Goals to sustainably use marine resources. Our study presents the first high‐resolution benthic habitat map from Greenland integrating analyses of multibeam bathymetry and backscatter data, and ground‐truth data including video sled, drop camera and day grab. The pilot area of 30 × 20 km is located on the continental shelf in central Disko Bay, West Greenland and all data were collected in a single, 10‐day survey. Multibeam bathymetry data were gridded to a 10 × 10 m resolution, whereas backscatter mosaic was built from a 1 × 1 m grid cell to obtain higher resolution manifestation of seafloor properties. Ground‐truth data consisted of 14 video transects, 17 drop camera deployments, and 17 sediment samples. Our results were verified with the published shallow seismic and vibrocore data from the Disko Bay region to link the geological background with the sedimentary environment. We distinguished five physical habitats in the area, based on the distribution of sediment types, water depth with general water masses and morphology. In addition, numerous gas seeps alongside pockmarks were observed in the area, as well as recent iceberg ploughmarks. The identified habitats were associated with two basic communities of benthic fauna, linked primarily to the distribution of sediments and representing hard bottom habitats (sessile fauna) and soft bottom habitats (shrimp/polychaetes). Our study is the first step toward mapping the entire seafloor of Disko Bay to provide a scientific context for the management of seafloor and marine resources.
Are Remote Sensing Evapotranspiration Models Reliable Across South American Ecoregions?
Authors: Melo D. C. D. , Anache J. A. A. , Borges V. P. , Miralles D. G. , Martens B. , Fisher J. B. , Nóbrega R. L. B. , Moreno A. , Cabral O. M. R. , Rodrigues T. R. , Bezerra B. , Silva C. M. S. , Neto A. A. Meira , Moura M. S. B. , Marques T. V. , Campos S. , Nogueira J. S. , Rosolem R. , Souza R. M. S. , Antonino A. C. D. , Holl D. , Galleguillos M. , Perez‐Quezada J. F. , Verhoef A. , Kutzbach L. , Lima J. R. S. , Souza E. S. , Gassman M. I. , Perez C. F. , Tonti N. , Posse G. , Rains D. , Oliveira P. T. S. , Wendland E.
Published: October 2021

Many remote sensing‐based evapotranspiration (RSBET) algorithms have been proposed in the past decades and evaluated using flux tower data, mainly over North America and Europe. Model evaluation across South America has been done locally or using only a single algorithm at a time. Here, we provide the first evaluation of multiple RSBET models, at a daily scale, across a wide variety of biomes, climate zones, and land uses in South America. We used meteorological data from 25 flux towers to force four RSBET models: Priestley–Taylor Jet Propulsion Laboratory (PT‐JPL), Global Land Evaporation Amsterdam Model (GLEAM), Penman–Monteith Mu model (PM‐MOD), and Penman–Monteith Nagler model (PM‐VI). was predicted satisfactorily by all four models, with correlations consistently higher () for GLEAM and PT‐JPL, and PM‐MOD and PM‐VI presenting overall better responses in terms of percent bias (%). As for PM‐VI, this outcome is expected, given that the model requires calibration with local data. Model skill seems to be unrelated to land‐use but instead presented some dependency on biome and climate, with the models producing the best results for wet to moderately wet environments. Our findings show the suitability of individual models for a number of combinations of land cover types, biomes, and climates. At the same time, no model outperformed the others for all conditions, which emphasizes the need for adapting individual algorithms to take into account intrinsic characteristics of climates and ecosystems in South America.
Evolution of the Koma Bangou Gold Panning Site (Niger) From 1984 to 2020 Using Landsat Imagery
Authors: Abass Saley A. , Baratoux D. , Baratoux L. , Ahoussi K. E. , Yao K. A. , Kouamé K. J.
Published: October 2021

The severe drought of 1983–1984 in the Sahel region, and its socio‐economic impacts for people relying on farming had for consequence the first major gold rush at Koma Bangou in the southwestern part of Niger. Initiated in 1984, the gold panning activities were interrupted from 1989 to 1999 with exploration permits assigned to the mining industry. The site was reclassified at the year‐end 1999 as a gold panning site and artisanal mining resumed until present‐day. Gold panning activities such as ore extraction and cyanide processing produced mining waste including rocks, mine tailings, and treatment residues. Mining waste is a serious environmental, health and safety problem. Multispectral Landsat images (TM4‐5, ETM7+, OLI/TIRS) acquired between 1984 and 2020 were used to map the spatial evolution of waste generated by gold panning activities at Koma Bangou. Different processing methods were tested, including Minimum Noise Fraction (MNF) transform, Band Ratio (BR), and Feature Oriented Principal Component Selection (FPCS). The FPCS applied to hydroxyl‐bearing minerals appears to be most efficient to map gold extraction and cyanidation waste areas. The waste surface associated with ore extraction has increased from 9.43 ha in 1984 to 234.20 ha in 2020, with continuous expansion during the period of clandestine activity (1989–1999). The waste surface associated with cyanidation has increased from 5.56 ha in 2009 (the year of cyanide treatment introduction) to 99.53 ha in 2020. Landsat multispectral imagery proved a suitable data source for monitoring the evolution of gold mining waste and consequences of public policies at Koma Bangou.
Clustering Supported Classification of ChemCam Data From Gale Crater, Mars
Authors: Rammelkamp Kristin , Gasnault Olivier , Forni Olivier , Bedford Candice C. , Dehouck Erwin , Cousin Agnès , Lasue Jeremie , David Gaël , Gabriel Travis S. J. , Maurice Sylvestre , Wiens Roger C.
Published: October 2021

The Chemistry and Camera (ChemCam) instrument on board the Mars Science Laboratory (MSL) rover Curiosity has collected a very large and unique data set of in‐situ spectra and images of Mars since landing in August 2012. More than 800,000 single shot laser‐induced breakdown spectroscopy (LIBS) spectra measured on more than 2,500 individual targets were returned so far by ChemCam. Such a data set is ideally suited for the application of statistical methods for the recognition of patterns that are difficult to observe by humans. In this work, we develop an approach relying on the feature extraction method Non‐Negative Matrix Factorization (NMF) and the repetition of k‐means clustering to classify ChemCam spectra. A strong consistency of the clustering results among the repetitions were found, which allowed us to identify six clusters representing the dominant compositions measured by ChemCam in Gale crater so far. By tracking clusters across the rover traverse from landing to sol 2756, we are able to provide a chemostratigraphic overview of the Gale crater from the ChemCam perspective. Transitions between major geologic groups (such as the Bradbury and the Mt. Sharp groups) are identifiable demonstrating that they are compositionally distinct, consistent with previous work. Compositional differences between their members also appear in the results. Furthermore, a first approach in which a random forest classifier was trained and validated with the obtained cluster assignments, reveals promising results for predicting cluster memberships of new ChemCam LIBS data acquired after sol 2756.
The Fuchuan Ophiolite in South China: Evidence for Modern‐Style Plate Tectonics During Rodinia Breakup
Authors: Huang Si‐Fang , Wang Wei , Kerr Andrew C. , Zhao Jun‐Hong , Xiong Qing , Wang Jian
Published: October 2021

Subduction initiation processes, such as those evidenced in the Izu‐Bonin‐Mariana (IBM) forearc crust are a key feature of modern‐style plate tectonics. However, the evidence for this process in the Precambrian is limited, due to the scarcity of ophiolite suites and in particular a lack of typical complete ophiolitic sequences similar to those observed in Phanerozoic ophiolites. Mineral analyses of olivine, orthopyroxene, and chrome spinel from the harzburgite and two types of clinopyroxene from the cumulate gabbro of the Fuchuan ophiolite, South China suggest formation in a Neoproterozoic subduction system similar to the IBM. High temperature (1,000–1,200°C), low pressure along with a high degree of melt extraction (>18%) have been recorded in the harzburgite. This evidence, in conjunction with magma evolution from forearc basalt to boninite to hydrous calc‐alkaline magmatism, recorded in the crustal section of the Fuchuan ophiolite indicates a transition from initial to mature subduction in a forearc setting. Statistical analysis of global ophiolites through time suggests that IBM‐like subduction systems may have successfully operated since at least the latest Neoproterozoic (ca. 1,000 Ma) and be pervasive on Earth from ca. 850 Ma. Additional evidence for Neoproterozoic ophiolites from India, Siberia, and Arabian‐Nubian Shield, which are also similar to the IBM forearc ophiolite, suggests that cold and deep subduction became much more common in the Neoproterozoic (ca. 850 Ma) around the periphery of the Rodinia supercontinent. This IBM‐like subduction system may have acted as the geodynamic trigger for the break‐up of Rodinia.
MJO Initiation Triggered by Amplification of Upper‐Tropospheric Dry Mixed Rossby‐Gravity Waves
Authors: Takasuka Daisuke , Kohyama Tsubasa , Miura Hiroaki , Suematsu Tamaki
Published: October 2021

A possibly important dynamical process for the Madden–Julian oscillation (MJO) convective initiation is proposed. An MJO event during the “CINDY2011” field campaign is triggered by eastward‐moving lower‐tropospheric mixed Rossby‐gravity (MRG) wave packets, and its leading precursor is predominance of upper‐tropospheric MRGs in the Indian Ocean (IO). Simple three‐dimensional model experiments reveal that the upper‐tropospheric MRGs in the IO are amplified particularly in the western IO (WIO) by their westward advection and wave accumulation due to the upper‐level convergence in mean easterlies of the Walker circulation. The model also predicts downward dispersion of the amplified upper‐tropospheric MRGs and resultant lower‐tropospheric MRG wave packet formation. This MRG evolution consistently explains the MJO initiation process during CINDY2011, which is further verified by ray tracing for MRGs. Upper‐tropospheric circumnavigating Kelvin waves assist the proposed mechanism by promoting MRG‐wave accumulation (advection) in their westerly (easterly) phases via enhanced zonal convergence and weakened easterlies (enhanced easterlies).
Waves Generated by Discrete and Sustained Gas Eruptions With Implications for Submarine Volcanic Tsunamis
Authors: Shen Yaxiong , Whittaker Colin N. , Lane Emily M. , White James D. L. , Power William , Melville Bruce W.
Published: October 2021

Submarine volcanic eruptions can perturb the water surface and subsequently generate localized tsunamis. Herein waves are produced in analogous laboratory experiments by injections of non‐condensable expanding air into fresh water. By varying source pressures, jet durations and water depths, we obtain two key results. There exists a saturation duration above which the maximum wave height will not increase as the eruption continues. Apart from in extremely shallow or deep water depths, this saturation duration is positively correlated with the source intensity and negatively with the water depth. There also exists a critical water depth where an eruption with a given source intensity can generate the largest waves. When an eruption lasts less than the saturation duration, increasing the eruption duration will increase the critical water depth and the corresponding maximum wave height. The saturation duration and critical water depth are the primary controls on tsunami size and hazard.
Strong Diurnal Pulsing of Cold Clouds in Rapidly Intensifying Tropical Cyclones
Authors: Zhang Xinyan , Xu Weixin
Published: October 2021

The radially outward propagating diurnal signal in the upper‐level clouds (diurnal pulse) is a prominent cyclical feature of tropical cyclones (TCs). This study examines relationships between diurnal pulses and TC intensity changes using satellite Infrared data from 2001 to 2018. The occurrence and duration of diurnal pulses 24 hr prior to or during TC intensity change are strongly correlated with TC intensification rate. Rapidly intensifying (RI) TCs have a markedly higher frequency (60%–80%) of very long‐duration pulse (15 hr) and significantly longer mean pulse duration than steady‐state (40%–50%) and gradually intensifying TCs (50%–60%). Long‐duration pulses are infrequent in weakening TCs (20%–30%). Diurnal pulse frequency and duration are highly correlated with the initial cloud‐top cooling rate and very cold‐cloud fraction in the inner core, but less related to the initial TC intensity. In short, strong diurnal pulsing of cold clouds is an evident signature prior to or during the RI of TCs.
Ice‐Shelf Basal Melt Channels Stabilized by Secondary Flow
Authors: Wearing M. G. , Stevens L. A. , Dutrieux P. , Kingslake J.
Published: October 2021

Ice‐shelf basal channels form due to concentrated submarine melting. They are present in many Antarctic ice shelves and can reduce ice‐shelf structural integrity, potentially destabilizing ice shelves by full‐depth incision. Here, we describe the viscous ice response to a basal channel—secondary flow—which acts perpendicular to the channel axis and is induced by gradients in ice thickness. We use a full‐Stokes ice‐flow model to systematically assess the transient evolution of a basal channel in the presence of melting. Secondary flow increases with channel size and reduces the rate of channel incision, such that linear extrapolation or the Shallow‐Shelf Approximation cannot project future channel evolution. For thick ice shelves ( m) secondary flow potentially stabilizes the channel, but is insufficient to significantly delay breakthrough for thinner ice ( m). Using synthetic data, we assess the impact of secondary flow when inferring basal‐channel melt rates from satellite observations.
Geological Characteristics and Targets of High Scientific Interest in the Zhurong Landing Region on Mars
Authors: Zhao Jiannan , Xiao Zijun , Huang Jun , Head James W. , Wang Jiang , Shi Yutong , Wu Bo , Wang Le
Published: October 2021

We used imaging, laser altimeter and thermal infrared data to map a 0.5 by 0.5° area containing the landing site of the Zhurong rover of the Tianwen‐1 mission. We analyzed the regional topography and thermophysical characteristics, and identified and characterized cones, impact craters, polygonal troughs, ridges and aeolian bedforms. An absolute model age of 757 ± 66 Ma was obtained for the major unit dominating the study area, younger than previous geological mapping results. We propose several targets of high scientific interest for Zhurong and a stratigraphic model composed of five layers (from bottom to top: Noachian basement, Early Hesperian volcanic ridged plains, Vastitas Borealis Formation materials, rocky materials and loose materials). The geomorphic features identified, the proposed stratigraphy and the regional geological evolution scenario set the stage for the Zhurong rover to continue to carry out its exploration of Mars.
Back‐Arc Extension of the Central Bransfield Basin Induced by Ridge–Trench Collision: Implications From Ambient Noise Tomography and Stress Field Inversion
Authors: Li Wei , Yuan Xiaohui , Heit Benjamin , Schmidt‐Aursch Mechita C. , Almendros Javier , Geissler Wolfram H. , Chen Yun
Published: October 2021

The Bransfield Basin is a young (∼4 Ma) back‐arc basin related to the remnant subduction of the Phoenix Plate that once existed along the entire Pacific margin of the Antarctic Peninsula. Based on a recently deployed amphibious seismic network, we use ambient noise tomography to obtain the S‐wave velocity structure in the Central Bransfield Basin (CBB). Combining with the stress field inverted from focal mechanisms, our images reveal that the CBB suffers a significant extension in the northwest‐southeast direction. The extension is strongest in the northeastern CBB with associated mantle exhumation and weakens to the southwest with decoupled deformations between the upper crust and lithospheric mantle. Such an along‐strike variation of extension can be explained by slab window formation and forearc rotation, which are associated with the Phoenix Plate detachment during the ridge–trench collisions at the southwest of the Hero Fracture Zone.
Improving Nowcasting of Convective Development by Incorporating Polarimetric Radar Variables Into a Deep‐Learning Model
Authors: Pan Xiang , Lu Yinghui , Zhao Kun , Huang Hao , Wang Mingjun , Chen Haonan
Published: October 2021

Nowcasting of convective storms is urgently needed yet rather challenging. Current nowcasting methods are mostly based on radar echo extrapolation, which suffer from the insufficiency of input information and ineffectiveness of model architecture. A novel deep‐learning (DL) model, FURENet, is designed for extracting information from multiple input variables to make predictions. Polarimetric radar variables, KDP and ZDR, which provide extra microphysics and dynamic structure information of storms, are fed into the model to improve nowcasting. Two representative cases indicate that KDP and ZDR can help the DL model better forecast convective organization and initiation. Quantitative statistical evaluation shows using FURENet, KDP, and ZDR synergistically improve nowcasting skills (CSI score) by 13.2% and 17.4% for the lead time of 30 and 60 min, respectively. Further evaluation shows the microphysical information provided by the polarimetric variables can enhance the DL model in understanding the evolution of convective storms and making more trustable nowcasts.
Turbulence Dictates Bedload Transport in Vegetated Channels Without Dependence on Stem Diameter and Arrangement
Authors: Zhao Tian , Nepf Heidi M.
Published: October 2021

Vegetation provides habitat and nature‐based solutions to coastal flooding and erosion, drawing significant interest in its restoration, which requires an understanding of sediment transport and retention. Laboratory experiments examined the influence of stem diameter and arrangement on bedload sediment transport by considering arrays of different stem diameter and mixed diameters. Bedload transport rate was observed to depend on turbulent kinetic energy, with no dependence on stem diameter, which was shown to be consistent with the impulse model for sediment entrainment. Existing predictors of bedload transport for bare beds, based on bed shear stress, were recast in terms of turbulence. The new turbulence‐based model predicted sediment transport measured in model canopies across a range of conditions drawn from several previous studies. A prediction of turbulence based on biomass and velocity was also described, providing an important step toward predicting turbulence and bedload transport in canopies of real vegetation morphology.
Mixing Enhancement Mechanisms in Aquifers Affected by Hydropeaking: Insights From Flow‐Through Laboratory Experiments
Authors: Ziliotto F. , Basilio Hazas M. , Rolle M. , Chiogna G.
Published: October 2021

This study presents high‐resolution flow‐through experiments investigating transport processes in a laboratory setup mimicking an aquifer affected by hydropeaking (i.e., abrupt fluctuations in the river stage by the release or storage of water in reservoirs). Highly transient flow conditions were experimentally generated by sudden changes of the water level in two rivers in hydraulic contact with an unconfined aquifer. High‐resolution image analysis and depth‐resolved, high‐frequency sampling at the outlet allowed monitoring of the spatio‐temporal evolution and the breakthrough of a dye tracer plume in the porous medium. The plume spreading and mixing were quantified by moment analysis and entropy‐based metrics of the scalar field. We show that hydropeaking strongly enhances spreading and mixing in the subsurface (up to 249.5% and 41.8% in these experiments) and demonstrate the relevance of considering highly transient flow regimes to properly capture transport and mixing‐controlled biogeochemical reactions at the surface water ‐ groundwater interface.
Impact of the Juan Fernandez Ridge on the Pampean Flat Subduction Inferred From Full Waveform Inversion
Authors: Gao Yajian , Yuan Xiaohui , Heit Benjamin , Tilmann Frederik , van Herwaarden Dirk‐Philip , Thrastarson Solvi , Fichtner Andreas , Schurr Bernd
Published: October 2021

A new seismic model for crust and upper mantle of the south Central Andes is derived from full waveform inversion, covering the Pampean flat subduction and adjacent Payenia steep subduction segments. Focused crustal low‐velocity anomalies indicate partial melts in the Payenia segment along the volcanic arc, whereas weaker low‐velocity anomalies covering a wide zone in the Pampean segment are interpreted as remnant partial melts. Thinning and tearing of the flat Nazca slab is inferred from gaps in the slab along the inland projection of the Juan Fernandez Ridge. A high‐velocity anomaly in the mantle below the flat slab is interpreted as relic Nazca slab segment, which indicates an earlier slab break‐off triggered by the buoyancy of the Juan Fernandez Ridge during the flattening process. In Payenia, large‐scale low‐velocity anomalies atop and below the re‐steepened Nazca slab are associated with the re‐opening of the mantle wedge and sub‐slab asthenospheric flow, respectively.
New Paleomagnetic Constraints on the Cretaceous Tectonic Framework of the Antarctic Peninsula
Authors: Gao Liang , Pei Junling , Zhao Yue , Yang Zhenyu , Riley Teal R. , Liu Xiaochun , Zhang Shuan‐Hong , Liu Jian‐Min
Published: October 2021

Understanding the tectonic framework of the Antarctic Peninsula is hindered by a paucity of paleomagnetic data from key locations. In this study, we present paleomagnetic data from the South Shetland Islands, to the northwest of the Antarctic Peninsula, which provides valuable paleoposition constraints on the Western domain of the Antarctic Peninsula. We report a key reliable paleopole (58.1°S, 354.3°E, A95 = 6.3°) from Livingston Island in the South Shetland Islands at ∼102 Ma. Plate reconstruction models from the Early Cretaceous attach the South Shetland Islands to the Pacific margin of southern Patagonia‐Fuegian Andes at ∼140 Ma. The South Shetland Islands then experienced southward translation to its current position to the northwest of the Antarctic Peninsula following counterclockwise rotation during ∼100–90 Ma. A similar counterclockwise rotation has also been identified from southern Patagonia‐Fuegian Andes but is absent in the Antarctic Peninsula, suggesting a direct affinity between the South Shetland Islands and southern Patagonia‐Fuegian Andes. However, the consistent, almost northward Cretaceous paleomagnetic declination in the Antarctic Peninsula, and the near‐synchronous tectonic‐magmatic history between the Antarctic Peninsula and the southern Patagonia‐Fuegian Andes support an autochthonous continental subduction model for most of the Antarctic Peninsula.
Exploring the Effects of Rooftop Mitigation Strategies on Urban Temperatures and Energy Consumption
Authors: Zonato A. , Martilli A. , Gutierrez E. , Chen F. , He C. , Barlage M. , Zardi D. , Giovannini L.
Published: October 2021

This paper describes and evaluates physical parameterizations accounting for the effect of rooftop mitigation strategies (RMSs) on the urban environment, in the context of the mesoscale model Weather Research and Forecasting (WRF). Through the new implementation, the sensitivity of near‐surface air temperature and building energy consumption to different RMSs is evaluated by means of numerical simulations in idealized urban areas, for typical summer and winter conditions. Rooftop mitigation strategies considered include cool roofs, green roofs, and rooftop photovoltaic panels. The reference case simulations are performed assuming buildings made by bricks, with roof composed of clay tiles. Results indicate that near‐surface air temperature is reduced by cool and green roofs during summer: cool roofs are the most efficient in decreasing air temperature, followed by irrigated green roofs. Photovoltaic panels, instead, induce a temperature increase during daytime and a small decrease during nighttime. Cool roofs reveal to be the most efficient strategy in reducing the energy consumption by air conditioning systems. During wintertime, green roofs maintain a higher near‐surface air temperature than clay tile roofs and largely decrease energy consumption. Even PVPs increase air temperature, as in the summer case. On the other hand, cool roofs reduce near‐surface air temperature during daytime, inducing an increase in energy consumption. The results presented here show that the parameterization schemes implemented in the WRF model can be a valuable tool to evaluate the effects of mitigation strategies in the urban environment.
On the Development of GFDL's Decadal Prediction System: Initialization Approaches and Retrospective Forecast Assessment
Authors: Yang Xiaosong , Delworth Thomas L. , Zeng Fanrong , Zhang Liping , Cooke William F. , Harrison Matthew J. , Rosati Anthony , Underwood Seth , Compo Gilbert P. , McColl Chesley
Published: October 2021

Using GFDL's new coupled model SPEAR, we have developed a decadal coupled reanalysis/initialization system (DCIS) that does not use subsurface ocean observations. In DCIS, the winds and temperature in the atmosphere, along with sea surface temperature (SST), are restored to observations. Under this approach the ocean component of the coupled model experiences a sequence of surface heat and momentum fluxes that are similar to observations. DCIS offers two initialization approaches, called A1 and A2, which differ only in the atmospheric forcing from observations. In A1, the atmospheric winds/temperature are restored toward the JRA reanalysis; in A2, surface pressure observations are assimilated in the model. Two sets of coupled reanalyses have been completed during 1961–2019 using A1 and A2, and they show very similar multi‐decadal variations of the Atlantic Meridional Overturning Circulation (AMOC). Two sets of retrospective decadal forecasts were then conducted using initial conditions from the A1 and A2 reanalyses. In comparison with previous prediction system CM2.1, SPEAR‐A1/A2 shows comparable skill of predicting the North Atlantic subpolar gyre SST, which is highly correlated with initial values of AMOC at all lead years. SPEAR‐A1 significantly outperforms CM2.1 in predicting multi‐decadal SST trends in the Southern Ocean (SO). Both A1 and A2 have skillful prediction of Sahel precipitation and the associated ITCZ shift. The prediction skill of SST is generally lower in A2 than A1 especially over SO presumably due to the sparse surface pressure observations.
Cenozoic Dextral Shearing Along the Arusan Sector of the Great Kavir–Doruneh Fault System (Central Iran)
Authors: Zanchi Andrea , Zanchetta Stefano , Berra Fabrizio , Mattei Massimo , Javadi Hamid Reza , Montemagni Chiara
Published: October 2021

The structural analysis of large intracontinental wrench faults is fundamental for deciphering the long‐term evolution of continental crust in complex areas in terms of their geodynamic evolution and large‐scale crustal block displacements. In this contribution, we demonstrate a pre‐Miocene dextral activity of the present‐day left‐lateral Great Kavir ‐ Doruneh Fault System (GKDFS, Central Iran), one of the major intracontinental active strike‐slip faults extending from the Afghan border to the Nain region between Central Iran and the Sanandaj‐Sirjan Zone. We document important dextral shearing recorded along a segment of the GKDFS, the Arusan Fault System (AFS), located east of Jandaq, close to the present‐day active trace of the GKDFS. The AFS include several ENE‐WSW striking strands exposed for a length of more than 50 km, which couple pre‐Cretaceous ophiolites and metamorphic basement units with the Cretaceous succession of the Khur basin. The fault shows transpressional structures consistent with a dextral shear including thrusts and en échelon folds affecting the Cretaceous carbonate units. Paleostress reconstruction based on mesoscopic fault analysis and related folds geometry allowed to establish vorticity parameters indicating that deformation occurred close to a total simple shear regime with a calculated Wk between 0.9 and 1. The enormous Meso‐Cenozoic dextral displacements occurred along the AFS and along the entire GKDFS are attested by the up to several hundreds of kilometers offset of the Paleotethys suture zone, from NE Iran to the western border of Central Iran.
Double Averaging Analysis Applied to a Large Eddy Simulation of Coupled Turbulent Overlying and Porewater Flow
Authors: Lian Yan Ping , Dallmann Jonathan , Sonin Benjamin , Roche Kevin R. , Packman Aaron I. , Liu Wing Kam , Wagner Gregory J.
Published: October 2021

Freestream turbulence in rivers is a key contributor to the flux of dissolved nutrients, carbon, and other ecologically important solutes into porewater. To advance understanding of turbulent hyporheic exchange and porewater transport, we investigate flow over and through a rough bed of spheres using large eddy simulation (LES). We apply double averaging (combined space and time averaging) to the LES results to determine the mean velocity distribution, momentum balance, and drag forces. Our simulations show large‐scale freestream structures interacting strongly with vortices generated at the surfaces of individual spheres to control turbulent momentum fluxes into the bed. The transition between turbulent flow and Darcy flow occurs over the first row of spheres, where turbulence decays rapidly and turbulent kinetic energy, Reynolds stress, and drag forces peak. Below this region, turbulence is only present in the high‐velocity flow in open pore throats. Experimental observations suggest that minimum mean porewater velocity occurs in the first open pore space below the transition region, but our results show that the minimum occurs between the first and second pore spaces. The simulation mean porewater velocities are approximately half those captured in measurements because the model resolves the entire flow continuum while measurements can access high‐velocity fluid in open pores. The high‐resolution dual time‐space averaging of the LES resolves both turbulent and mean flow features that are important to interfacial solute and particle fluxes, providing a means to include turbulent hyporheic exchange in upscaled river models, which has not been achieved to date.
Mesenchymal stem cell-derived small extracellular vesicles mitigate oxidative stress-induced senescence in endothelial cells via regulation of miR-146a/Src
Authors: Xiao Xian , Xu Meiqian , Yu Hongliang , Wang Liping , Li Xiaoxia , Rak Janusz , Wang Shihua , Zhao Robert Chunhua
Published: October 2021

Senescent endothelial cells (ECs) could impair the integrity of the blood vessel endothelium, leading to vascular aging and a series of diseases, such as atherosclerosis, diabetes. Preventing or mitigating EC senescence might serve as a promising therapeutic paradigm for these diseases. Recent studies showed that small extracellular vesicles (sEV) have the potential to transfer bioactive molecules into recipient cells and induce phenotypic changes. Since mesenchymal stem cells (MSCs) have long been postulated as an important source cell in regenerative medicine, herein we investigated the role and mechanism of MSC-derived sEV (MSC-sEV) on EC senescence. In vitro results showed that MSC-sEV reduced senescent biomarkers, decreased senescence-associated secretory phenotype (SASP), rescued angiogenesis, migration and other dysfunctions in senescent EC induced by oxidative stress. In the In vivo natural aging and type-2 diabetes mouse wound-healing models (both of which have senescent ECs), MSC-sEV promoted wound closure and new blood vessel formation. Mechanically, miRNA microarray showed that miR-146a was highly expressed in MSC-sEV and also upregulated in EC after MSC-sEV treatment. miR-146a inhibitors abolished the stimulatory effects of MSC-sEV on senescence. Moreover, we found miR-146a could suppress Src phosphorylation and downstream targets VE-cadherin and Caveolin-1. Collectively, our data indicate that MSC-sEV mitigated endothelial cell senescence and stimulate angiogenesis through miR-146a/Src.
Brief report on a phase I/IIa study to assess the safety, tolerability, and immune response of AGMG0201 in patients with essential hypertension
Authors: Nakagami Hironori , Ishihama Tetsuya , Daikyoji Yuichi , Sasakura Chieka , Yamada Ei , Morishita Ryuichi
Published: October 2021

We have been developing an angiotensin II vaccine for hypertension. We conducted a placebo-controlled dose escalation study to investigate the safety, tolerability, and immunological responses of this angiotensin II vaccine (AGMG0201). AGMG0201 was administered to participants with mild to moderate hypertension between 18 and 79 years of age. Twelve patients each were enrolled in the low-dose and high-dose groups. Within each group, subjects were randomly assigned to receive either the active study drug or a placebo at a ratio of 3:1. Each participant received a single intramuscular injection, followed by a second injection 30 days later, and was monitored for 360 days after the second dose. The results showed that most treatment-related adverse events were classified as mild or moderate in severity, including pain and erythema at the injection site. Anti-angiotensin II antibodies were observed in the AGMG0201 patients, especially in the high-dose group. Overall, AGMG0201 was well tolerated.
A Japan nationwide web-based survey of patient preference for renal denervation for hypertension treatment
Authors: Kario Kazuomi , Kagitani Hideaki , Hayashi Shoko , Hanamura Satsuki , Ozawa Keisuke , Kanegae Hiroshi
Published: October 2021

Renal denervation is a potential alternative to antihypertensive drug therapy. However, data on patient preference for this treatment option are limited and there are no data specifically from Asian patients. This study evaluated patient preference for renal denervation in patients with hypertension from Japan. Patients were a subset of those who participated in a March 2020 online electronic survey of patients with hypertension who had regularly visited medical institutions for treatment, were receiving antihypertensive drug therapy and had home blood pressure recordings available. The survey included a question about patient preference for treatment with renal denervation. A total of 2,392 patients were included (66% male, mean age 59.8 ± 11.6 years, mean duration of hypertension 11.4 ± 9.5 years). Preference for renal denervation was expressed by 755 patients (31.6%), and was higher in males than in females, in younger compared with older patients, in those with higher versus lower blood pressure, in patients who were less adherent versus more adherent to antihypertensive drug therapy, and in those who did rather than did not have antihypertensive drug-related side effects. Significant predictors of preference for renal denervation on logistic regression analysis were younger patient age, male sex, higher home or office systolic blood pressure, poor antihypertensive drug adherence, the presence of heart failure, and the presence of side effects during treatment with antihypertensive drugs. Overall, a relevant proportion of Japanese patients with hypertension expressed a preference for renal denervation. This should be taken into account when making shared decisions about antihypertensive drug therapy.
A DSC approach to adaptive dynamic region‐based tracking control for strict‐feedback non‐linear systems
Authors: Sun Xiaoming , Ge Shuzhi Sam
Published: October 2021

As an extension of the conventional set‐point control problem, the dynamic region‐based tracking control scheme with obstacle avoidance is proposed for a class of uncertain strict‐feedback non‐linear systems. A novel adaptive tracking controller is designed by a fusion of artificial potential field, recursive backstepping approach, neural networks, dynamic surface control technique, calculus method, and Lyapunov stability theory. In the proposed control scheme, the objective region cannot be required to have a regular shape or a fixed size for the passibility of the system in constrained space. The region tracking error is transformed into a new virtual error variable for recursively designing a dynamic surface controller, and the dimension of neural network inputs can be greatly reduced, especially for high‐order systems. The Lyapunov theorem is used to confirm the stability and uniform boundedness of all closed‐loop signals. Simulation results are provided to demonstrate the effectiveness of the proposed controller.
Complete/incomplete multi‐view subspace clustering via soft block‐diagonal‐induced regulariser
Authors: Hu Yongli , Luo Cuicui , Wang Boyue , Gao Junbin , Sun Yanfeng , Yin Baocai
Published: October 2021

This study proposes a novel multi‐view soft block diagonal representation framework for clustering complete and incomplete multi‐view data. First, given that the multi‐view self‐representation model offers better performance in exploring the intrinsic structure of multi‐view data, it can be nicely adopted to individually construct a graph for each view. Second, since an ideal block diagonal graph is beneficial for clustering, a ‘soft’ block diagonal affinity matrix is constructed by fusing multiple previous graphs. The soft diagonal block regulariser encourages a matrix to approximately have (not exactly) diagonal blocks, where is the number of clusters. This strategy adds robustness to noise and outliers. Third, to handle incomplete multi‐view data, multiple indicator matrices are utilised, which can mark the position of missing elements of each view. Finally, the alternative direction of multipliers algorithm is employed to optimise the proposed model, and the corresponding algorithm complexity and convergence are also analysed. Extensive experimental results on several real‐world datasets achieve the best performance among the state‐of‐the‐art complete and incomplete clustering methods, which proves the effectiveness of the proposed methods.