bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mesoscale and Submesoscale Processes in the Southeast Atlantic and Their Impact on the Regional Thermohaline Structure
Authors: Capuano Tonia Astrid , Speich Sabrina , Carton Xavier , Blanke Bruno 
Published: February 2018

AbstractThe turbulent processes in the Cape Basin, the southeasternmost gate of the Atlantic Ocean, play a key role in the transport and mixing of upper to intermediate water masses entering the area from the Indian Ocean, making them especially relevant for the Indo‐Atlantic transfer of heat and salt. In this paper, two numerical simulations at different horizontal resolutions are used to study mesoscale and submesoscale dynamics, their phenomenology, their evolution, and their impact on the local water masses. Submesoscale processes seasonally affect both, the upper and intermediate layers, but there are clear dynamical differences between the two layers. Several types of instabilities underline this spatial and temporal variability. Near the surface, mixed layer instabilities occur during winter, while mesoscale‐driven instabilities, as the symmetric type, prevail in summer. The connection between these two seasonal regimes is ensured, in anticyclonic eddies and within the mixed layers, by Charney baroclinic instabilities, involved in the local formation and subduction of mode water, that we have dubbed as Agulhas Rings mode water. Intermediate depths are instead characterized by mesoscale mechanisms of density compensation and lateral stirring of the tracer variance, triggering a significant filamentogenesis whose vertical scales are comparable to those mentioned in previous studies. This leads to a particularly efficient mixing of Antarctic Intermediate Waters of Indian and Atlantic origins. Lagrangian estimates highlight the new and significant role of fine scale structures in setting the water masses properties of upper and lower thermocline waters materializing the Indo‐Atlantic exchange and therefore potentially affecting the global ocean circulation.
The Climatological Impacts of Continental Surface Evaporation, Rainout, and Subcloud Processes on δD of Water Vapor and Precipitation in Europe
Authors: Christner Emanuel , Aemisegger Franziska , Pfahl Stephan , Werner Martin , Cauquoin Alexandre , Schneider Matthias , Hase Frank , Barthlott Sabine , Schädler Gerd 
Published: February 2018

AbstractAll types of applications of stable water isotopes, for example, for the reconstruction of paleotemperatures or for climate model validation, rely on a proper understanding of the mechanisms determining the isotopic composition of water vapor and precipitation. In this study, we use the isotope‐enabled limited‐area model COSMOiso to characterize the impacts of continental evapotranspiration, rainout, and subcloud processes on δD of European water vapor and precipitation. To this end, we first confirm a reliable implementation of the most important isotope fractionation processes in COSMOiso by comparing 5 years of modeled δD values with multiplatform δD observations from Europe (remote sensing observations of the δD of water vapor around 2.6 km above ground level, in situ δD measurements in near‐surface water vapor, and δD precipitation data from the Global Network of Isotopes in Precipitation). Based on six 15 year sensitivity simulations, we then quantify the climatological impacts of the different fractionation processes on the δD values. We find δD of European water vapor and precipitation to be most strongly controlled by rainout. Superimposed to this are the effect of subcloud processes, which especially affects δD in precipitation under warm conditions, and the effect of continental evapotranspiration, which exerts an important control over the δD of near‐surface water vapor. In future studies, the validated COSMOiso model can be employed in a similar way for a comprehensive interpretation of European isotope records from climatologically different time periods.
Comparisons of the Performance of δ13C and δ18O of Fagus sylvatica, Pinus sylvestris, and Quercus petraea in the Record of Past Climate Variations
Authors: Daux V. , Michelot‐Antalik A. , Lavergne A. , Pierre M. , Stievenard M. , Bréda N. , Damesin C. 
Published: February 2018

AbstractClimate reconstructions in temperate Europe have been widely based on oak species. However, other co‐occurring species, largely distributed in Europe, may be used for recording climate variability. In this paper, we documented the intertrees and interspecies variations over 1960–2007 of oxygen and carbon isotopic compositions in ring cellulose of Fagus sylvatica, Pinus sylvestris, and Quercus petraea co‐occurring in the Fontainebleau forest (France). Our results indicated that large levels of series replication (11 trees on average) were required to generate isotopic mean series representative of the populations. We calculated mean isotopic ratios higher in pine than in the deciduous species and hypothesized that these contrasts resulted from differences in stomatal conductance, phenology, and canopy structure and, for oxygen, also in water uptake depth and isotopic exchange rate. We found that δ18O and δ13C chronologies were significantly correlated to one another in the three species and responded primarily to air moisture and Tmax, which indicated that stomatal conductance was an important driver of changes in both types of records. We determined that the correlations were strong with the May to July climate variables in F. sylvatica and with the July and August ones in Q. petraea and P. sylvestris. We showed that the oxygen records were systematically more coherent than those of carbon. This study demonstrated that δ18O, and to a lesser extent δ13C, from the three different species are reliable proxies for reconstructing past hydroclimatic variations in Europe.
UAV Remote Sensing Can Reveal the Effects of Low‐Impact Seismic Lines on Surface Morphology, Hydrology, and Methane (CH4) Release in a Boreal Treed Bog
Authors: Lovitt J. , Rahman M. M. , Saraswati S. , McDermid G. J. , Strack M. , Xu B. 
Published: February 2018

AbstractPeatlands are globally significant stores of soil carbon, where local methane (CH4) emissions are strongly linked to water table position and microtopography. Historically, these factors have been difficult to measure in the field, constraining our capacity to observe local patterns of variability. In this paper, we show how remote sensing surveys conducted from unmanned aerial vehicle (UAV) platforms can be used to map microtopography and depth to water over large areas with good accuracy, paving the way for spatially explicit estimates of CH4 emissions. This approach enabled us to observe—for the first time—the effects of low‐impact seismic lines (LIS; petroleum exploration corridors) on surface morphology and CH4 emissions in a treed‐bog ecosystem in northern Alberta, Canada. Through compaction, LIS lines were found to flatten the observed range in microtopographic elevation by 46 cm and decrease mean depth to water by 15.4 cm, compared to surrounding undisturbed conditions. These alterations are projected to increase CH4 emissions by 20–120% relative to undisturbed areas in our study area, which translates to a total rise of 0.011–0.027 kg CH4 day−1 per linear kilometer of LIS (~2 m wide). The ~16 km of LIS present at our 61 ha study site were predicted to boost CH4 emissions by 20–70 kg between May and September 2016.
The Embrace Magnetometer Network for South America: Network Description and Its Qualification
Authors: Denardini C. M. , Chen S. S. , Resende L. C. A. , Moro J. , Bilibio A. V. , Fagundes P. R. , Gende M. A. , Cabrera M. A. , Bolzan M. J. A. , Padilha A. L. , Schuch N. J. , Hormaechea J. L. , Alves L. R. , Barbosa Neto P. F. , Nogueira P. A. B. , Picanço G. A. S. , Bertollotto T. O. 
Published: February 2018

AbstractThe present work is the first of a two‐part paper on the Embrace Magnetometer Network. In this part, we present the new Embrace Magnetometer Network (Embrace MagNet) in South America, which is originally planned to cover most of the eastern portion of the Southern America longitudinal sector by installing and operating fluxgate magnetometer stations. We discuss the purpose and scientific goals of the network, associated with aeronomy and space weather. We provide details on the instrumentation, location of the sensors, sensitivity matching process, gain matching process, and magnetometer installation. In addition, we present and discuss details about the data storage, near‐real time display, and availability.
The Critical Role of the Research Community in Space Weather Planning and Execution
Authors: Robinson Robert M. , Behnke Richard A. , Moretto Therese 
Published: February 2018

AbstractThe explosion of interest in space weather in the last 25 years has been due to a confluence of efforts all over the globe, motivated by the recognition that events on the Sun and the consequent conditions in interplanetary space and Earth's magnetosphere, ionosphere, and thermosphere can have serious impacts on vital technological systems. The fundamental research conducted at universities, government laboratories, and in the private sector has led to tremendous improvements in the ability to forecast space weather events and predict their impacts on human technology and health. The mobilization of the research community that made this progress possible was the result of a series of actions taken by the National Science Foundation (NSF) to build a national program aimed at space weather. The path forward for space weather is to build on those successes through continued involvement of the research community and support for programs aimed at strengthening basic research and education in academia, the private sector, and government laboratories. Investments in space weather are most effective when applied at the intersection of research and applications. Thus, to achieve the goals set forth originally by the National Space Weather Program, the research community must be fully engaged in the planning, implementation, and execution of space weather activities, currently being coordinated by the Space Weather Operations, Research, and Mitigation Subcommittee under the National Science and Technology Council.
The Value of Hydrograph Partitioning Curves for Calibrating Hydrological Models in Glacierized Basins
Authors: He Zhihua , Vorogushyn Sergiy , Unger‐Shayesteh Katy , Gafurov Abror , Kalashnikova Olga , Omorova Elvira , Merz Bruno 
Published: February 2018

AbstractThis study refines the method for calibrating a glacio‐hydrological model based on Hydrograph Partitioning Curves (HPCs), and evaluates its value in comparison to multidata set optimization approaches which use glacier mass balance, satellite snow cover images, and discharge. The HPCs are extracted from the observed flow hydrograph using catchment precipitation and temperature gradients. They indicate the periods when the various runoff processes, such as glacier melt or snow melt, dominate the basin hydrograph. The annual cumulative curve of the difference between average daily temperature and melt threshold temperature over the basin, as well as the annual cumulative curve of average daily snowfall on the glacierized areas are used to identify the starting and end dates of snow and glacier ablation periods. Model parameters characterizing different runoff processes are calibrated on different HPCs in a stepwise and iterative way. Results show that the HPC‐based method (1) delivers model‐internal consistency comparably to the tri‐data set calibration method; (2) improves the stability of calibrated parameter values across various calibration periods; and (3) estimates the contributions of runoff components similarly to the tri‐data set calibration method. Our findings indicate the potential of the HPC‐based approach as an alternative for hydrological model calibration in glacierized basins where other calibration data sets than discharge are often not available or very costly to obtain.
Quantifying Changes in Future Intensity‐Duration‐Frequency Curves Using Multimodel Ensemble Simulations
Authors: Ragno Elisa , AghaKouchak Amir , Love Charlotte A. , Cheng Linyin , Vahedifard Farshid , Lima Carlos H. R. 
Published: February 2018

AbstractDuring the last century, we have observed a warming climate with more intense precipitation extremes in some regions, likely due to increases in the atmosphere's water holding capacity. Traditionally, infrastructure design and rainfall‐triggered landslide models rely on the notion of stationarity, which assumes that the statistics of extremes do not change significantly over time. However, in a warming climate, infrastructures and natural slopes will likely face more severe climatic conditions, with potential human and socioeconomical consequences. Here we outline a framework for quantifying climate change impacts based on the magnitude and frequency of extreme rainfall events using bias corrected historical and multimodel projected precipitation extremes. The approach evaluates changes in rainfall Intensity‐Duration‐Frequency (IDF) curves and their uncertainty bounds using a nonstationary model based on Bayesian inference. We show that highly populated areas across the United States may experience extreme precipitation events up to 20% more intense and twice as frequent, relative to historical records, despite the expectation of unchanged annual mean precipitation. Since IDF curves are widely used for infrastructure design and risk assessment, the proposed framework offers an avenue for assessing resilience of infrastructure and landslide hazard in a warming climate.
Direct Growth of Highly Stable Patterned Graphene on Dielectric Insulators using a Surface‐Adhered Solid Carbon Source
Authors: Lee Eunho , Lee Seung Goo , Lee Hyo Chan , Jo Mankyu , Yoo Min Seok , Cho Kilwon 
Published: February 2018

AbstractA novel method is described for the direct growth of patterned graphene on dielectric substrates by chemical vapor deposition (CVD) in the presence of Cu vapor and using a solid aromatic carbon source, 1,2,3,4‐tetraphenylnapthalene (TPN), as the precursor. The UV/O3 treatment of the TPN film both crosslinks TPN and results in a strong interaction between the substrate and the TPN that prevents complete sublimation of the carbon source from the substrate during CVD. Substrate‐adhered crosslinked TPN is successfully converted to graphene on the substrate without any organic contamination. The graphene synthesized by this method shows excellent mechanical and chemical stability. This process also enables the simultaneous patterning of graphene materials, which can thus be used as transparent electrodes for electronic devices. The proposed method for the synthesis directly on substrates of patterned graphene is expected to have wide applications in organic and soft hybrid electronics.
Highly Augmented Drug Loading and Stability of Micellar Nanocomplexes Composed of Doxorubicin and Poly(ethylene glycol)–Green Tea Catechin Conjugate for Cancer Therapy
Authors: Liang Kun , Chung Joo Eun , Gao Shu Jun , Yongvongsoontorn Nunnarpas , Kurisawa Motoichi 
Published: February 2018

AbstractLow drug loading and instability in blood circulation are two key challenges that impede the successful clinical translation of nanomedicine, as they result in only marginal therapeutic efficacy and toxic side effects associated with premature drug leakage, respectively. Herein, highly stable and ultrahigh drug loading micellar nanocomplexes (MNCs) based on the self‐assembly of the anticancer drug doxorubicin (DOX) and a poly(ethylene glycol)–epigallocatechin‐3‐O‐gallate (EGCG) conjugate are developed. The formation of these MNCs is facilitated by strong favorable intermolecular interactions between the structurally similar aromatic EGCG and DOX molecules, which impart exceptionally high drug‐loading capability of up to 88% and excellent thermodynamic and kinetic stability. Unlike two clinical formulations of DOX—free DOX and liposomal DOX, which are not effective below their lethal dosages, these DOX‐loaded MNCs demonstrate significant tumor growth inhibition in vivo on a human liver cancer xenograft mouse model with minimal unwanted toxicity. Overall, these MNCs can represent a safe and effective strategy to deliver DOX for cancer therapy.
Extraordinary THz Transmission with a Small Beam Spot: The Leaky Wave Mechanism
Authors: Navarro‐Cía Miguel , Pacheco‐Peña Víctor , Kuznetsov Sergei A. , Beruete Miguel 
Published: February 2018

AbstractThe discovery of extraordinary optical transmission (EOT) through patterned metallic foils in the late 1990s was decisive for the development of plasmonics and cleared the path to employ small apertures for a variety of interesting applications all along the electromagnetic spectrum. However, a typical drawback often found in practical EOT structures is the large size needed to obtain high transmittance peaks. Consequently, practical EOT arrays are usually illuminated using an expanded (mimicking a plane wave) beam. Here, it is shown with numerical and experimental results in the THz range that high transmittance peaks can be obtained even with a reduced illumination spot exciting a small number of holes, provided that the structure has a sufficient number of lateral holes out of the illumination spot. These results shed more light on the prominent role of leaky waves in the underlying physics of EOT and have a direct impact on potential applications.
Brain Delivery of Multifunctional Dendrimer Protein Bioconjugates
Authors: Moscariello Pierpaolo , Ng David Y. W. , Jansen Malin , Weil Tanja , Luhmann Heiko J. , Hedrich Jana 
Published: February 2018

AbstractNeurological disorders are undoubtedly among the most alarming diseases humans might face. In treatment of neurological disorders, the blood‐brain barrier (BBB) is a challenging obstacle preventing drug penetration into the brain. Advances in dendrimer chemistry for central nervous system (CNS) treatments are presented here. A poly(amido)amine (PAMAM) dendrimer bioconjugate with a streptavidin adapter for the attachment of dendrons or any biotinylated drug is constructed. In vitro studies on porcine or murine models and in vivo mouse studies are performed and reveal the permeation of dendronized streptavidin (DSA) into the CNS. The bioconjugate is taken up mainly by the caveolae pathway and transported across the BBB via transcytosis escaping from lysosomes. After transcytosis DSA are delivered to astrocytes and neurons. Furthermore, DSA offer high biocompatibility in vitro and in vivo. In summary, a new strategy for implementing therapeutic PAMAM function as well as drug delivery in neuropathology is presented here.
Ordered PtPb/Pt Core/Shell Nanodisks as Highly Active, Selective, and Stable Catalysts for Methanol Reformation to H2
Authors: E Bin , Shao Qi , Bu Lingzheng , Bai Shuxing , Li Yujing , Huang Xiaoqing 
Published: February 2018

AbstractHerein, we report on unique bimetallic PtPb/Pt core/shell nanodisks consisting of structurally ordered PtPb hexagonal nanoplates as the core and the well‐organized Pt as the shell, as extremely active and selective catalysts towards CH3OH reformation. We found that the created Pt‐Pb nanodisks/C show the composition‐dependent activity with the optimized PtPb0.56 nanodisks/C being the most active for the CH3OH reformation to H2, 5.1 times higher than those of the commercial Pt/C. Significantly, only very limited carbon monoxide (CO) is produced during the CH3OH reformation, which is crucial for the practical application in fuel cells. The PtPb0.56 nanodisks/C is also more active for CH3OH reformation than PtPb hexagonal nanoplates/C and PtPb0.58 nanoparticles/C. X‐ray photoelectron spectroscopy (XPS) results reveal that the high ratio of Pt (0) to Pt (II) in Pt‐Pb nanodisks/C enhances the CH3OH reformation to H2, while the high content of Pb (0) is beneficial for decrease the CO production. Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) of CO adsorption shows that Pt‐Pb nanodisks can promote the activation of CO molecules by forming the carboxylate (CO2δ−) intermediates, leading to the low CO production.
Palladium Immobilized onto Functionalized Magnetic Nanoparticles as Robust Catalysts for Amination and Room‐Temperature Ullmann Homocoupling of Aryl Halides: A Walk Around the C−F Bond Activation
Authors: Moghaddam Firouz Matloubi , Pourkaveh Raheleh , Karimi Ashkan , Ayati Seyed Ebrahim 
Published: February 2018

AbstractThe first example of a heterogeneous catalytically active system for Buchwald–Hartwig and Ullmann homocoupling of unactivated aryl halides (fluorobenzene) is presented. The novel magnetic heterogeneous palladium catalyst was synthesized by immobilization of palladium ions onto an aminopyridine‐functionalized Fe3O4. The catalyst was fully characterized by FTIR spectroscopy, temperature‐programmed reduction, thermogravimetric analysis, CHN elemental analysis, transmission electron microscopy, field‐emission scanning electron microscopy, X‐ray diffraction, energy‐dispersive X‐ray spectroscopy, and atomic absorption spectroscopy. By using this catalyst system, various types of primary and secondary amines reacted with different types of aryl halides, even fluorobenzene. This catalyst can also efficiently transform all types of haloarenes into biaryl derivatives by Ullmann reaction at room temperature. Therefore, it is a promising catalyst in the area of C−F bond activation. The catalyst was reused several times and no significant loss of activity was observed.
Effect of nanodiamond additives on the structure and gas‐transport properties of a poly(phenylene–isophtalamide) matrix
Authors: Avagimova Natalia , Polotskaya Galina , Toikka Alexander , Pulyalina Alexandra , Morávková Zuzana , Trchová Miroslava , Pientka Zbyněk 
Published: February 2018

ABSTRACTNanodiamonds (NDs) are specific carbon nanoparticles approximately 5 nm in diameter with a large and accessible surface containing functional groups. Poly(phenylene–isophtalamide) (PA)–ND composites were prepared by solid‐phase dispersal and used for dense film formation. The PA–ND composites were analyzed by Fourier transform infrared spectroscopy. The membrane structure was determined on the basis of density measurement and morphological study by atomic force microscopy. The gas‐transport properties were measured over a wide range of temperatures from 30 to 100 °C for the following series of penetrants: H2, N2, O2, and CO2. The experimental data of gas permeability were compared with the permeability values calculated from Maxwell's model. Data on the permeability and diffusion coefficients were used to calculate the activation energies. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46320.