bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ice fabric in an Antarctic ice stream interpreted from seismic anisotropy
Authors: Smith Emma C. , Baird Alan F. , Kendall J. Michael , Martín Carlos , White Robert S. , Brisbourne Alex M. , Smith Andrew M. 
Published: April 2017

AbstractHere we present new measurements of an anisotropic ice fabric in a fast moving (377 ma−1) ice stream in West Antarctica. We use ∼6000 measurements of shear wave splitting observed in microseismic signals from the bed of Rutford Ice Stream, to show that in contrast to large‐scale ice flow models, which assume that ice is isotropic, the ice in Rutford Ice Stream is dominated by a previously unobserved type of partial girdle fabric. This fabric has a strong directional contrast in mechanical properties, shearing 9.1 times more easily along the ice flow direction than across flow. This observed fabric is likely to be widespread and representative of fabrics in other ice streams and large glaciers, suggesting it is essential to consider anisotropy in data‐driven models to correctly predict ice loss and future flow in these regions. We show how passive microseismic monitoring can be effectively used to provide these data.
Why does the locally induced temperature response to land cover change differ across scenarios?
Authors: Winckler J. , Reick C. H. , Pongratz J. 
Published: April 2017

AbstractLand cover change (LCC) affects temperature locally. The underlying biogeophysical effects are influenced not only by land use (location and extent) but also by natural biogeographic shifts and background climate. We examine the contributions of these three factors to surface temperature changes upon LCC and compare them across Coupled Model Intercomparison Project phase 5 (CMIP5) scenarios. To this end, we perform global deforestation simulations with an Earth system model to deduce locally induced changes in surface temperature for historical and projected forest cover changes. We find that the dominant factors differ between historical and future scenarios: the local temperature response is historically dominated by the factor land use change, but the two other factors become just as important in scenarios of future land use and climate. An additional factor contributing to differences across scenarios is the dependence on the extent of forests before LCC happens: For most locations, the temperature response is strongest when starting deforestation from low forest cover fractions.
Submicroscopic metallic iron in lunar soils estimated from the in situ spectra of the Chang'E‐3 mission
Authors: Wang Zhenchao , Wu Yunzhao , Blewett David T. , Cloutis Edward A. , Zheng Yongchun , Chen Jun 
Published: April 2017

AbstractSubmicroscopic metallic iron (SMFe) created by space weathering has strong effects on the optical properties of the lunar surface. Spectra measured in situ by the visible‐near‐infrared spectrometer (VNIS) on board the Chang'E‐3 Yutu rover were used to investigate optical maturity differences at the CE‐3 landing site caused by lander exhaust. SMFe abundances were estimated using Hapke's radiative transfer model. Analysis of the spectrum for a minimally disturbed soil indicates that it contains 0.368 wt % SMFe, corresponding to an Is/FeO maturity index of ~53 and indicating that the landing site is submature. The soil at a location that was more disturbed contains 0.217 wt % SMFe, suggesting that the material removed by the rocket blast is more weathered than the regolith that remained behind. We conclude that maturity differences related to removal of the finest, highly mature particles play a major role in the observed reflectance changes associated with rocket blast.
Plate coupling and strain in the far western Aleutian arc modeled from GPS data
Authors: Kogan Mikhail G. , Frolov Dmitry I. , Vasilenko Nikolay F. , Freymueller Jeffrey T. , Steblov Grigory M. , Ekström Göran , Titkov Nikolay N. , Prytkov Alexandr S. 
Published: April 2017

AbstractThe Aleutian and Kuril‐Kamchatka arcs meet at a triple junction of the Pacific (PAC), Bering (BER), and North American (NAM) plates. We invert GPS observations from the westernmost Aleutian (Komandorsky) Islands and Kamchatka for the fault locking depth and block motion in the far western Aleutian transform boundary. Three boundary models were considered: (1) only the Aleutian thrust fault without a trench‐normal component, (2) only a strike‐slip fault in the back arc north of the Komandorsky Islands, and (3) a rigid Komandorsky sliver bounded by the Aleutian and back‐arc faults. Observed velocities prefer Model 3, with a secular westward sliver velocity of 51 mm/a relative to NAM (two thirds of the total PAC‐NAM motion). The observed velocities are ~10% slower because of elastic strain from boundary faults. The best fitting locking depth of faults bounding the sliver is 12 km, which is similar to depths observed in diverse tectonic environments.
Time‐evolving seismic tomography: The method and its application to the 1989 Loma Prieta and 2014 South Napa earthquake area, California
Authors: Tong Ping , Yang Dinghui , Li Dongzhuo , Liu Qinya 
Published: April 2017

AbstractWe propose a time‐evolving approach to conduct traveltime seismic tomography in the 1989 Mw 6.9 Loma Prieta earthquake and 2014 Mw 6.0 South Napa earthquake area, California. The recording period of the chosen seismic data between 1 January 1967 and the day before the 2014 South Napa earthquake is divided into two time windows, separated by the 1989 Loma Prieta earthquake. In each time window the subsurface velocity structure is iteratively updated. Starting from the final model of the first time window, the velocity model has been successively improved throughout iterations in the second time window, indicating that the traveltime data of later time windows have provided extra information to refine the subsurface images. Strong heterogeneities are observed in the final P wave velocity model. Both of the two large earthquakes occurred at transition zones in between high VP and low VP anomalies. In all, this study shows the effectiveness of the time‐evolving seismic tomography method.
The charge state of electrostatically transported dust on regolith surfaces
Authors: Schwan J. , Wang X. , Hsu H.‐W. , Grün E. , Horányi M. 
Published: April 2017

AbstractThe charge state of dust particles on regolith surfaces exposed to ultraviolet radiation or plasma is investigated for understanding the role of electrostatic dust transport in the surface evolution of airless planetary bodies. Our charge measurement shows that the regolith dust that can be electrostatically transported or lofted carries large negative charges. This result is consistent with our “patched charge model,” which predicts that dust particles forming microcavities in the regolith surfaces can attain large negative charges by collecting photoelectrons and/or secondary electrons emitted from neighboring particles and the resulting repulsive forces between these negatively charged particles lead to their mobilization. The observed negative charge polarity is contrary to the generally expected positive charges on the regolith dust emitting photoelectrons. The measured negative charges are orders of magnitude larger than the prediction by classical charging models. Our laboratory measurements provide critical initial charging conditions for regolith dust dynamics studies.
Land loss by pond expansion on the Mississippi River Delta Plain
Authors: Ortiz Alejandra C. , Roy Samapriya , Edmonds Douglas A. 
Published: April 2017

AbstractThe world's river deltas may collapse under the combined effects of rising sea levels, subsidence, and reduced sediment supply. Saving these deltaic environments requires quantifying processes driving collapse. In the Mississippi River Delta, rapid land loss offers an important opportunity to test existing theories for marsh collapse. We use Landsat images to examine how pond expansion by edge retreat contributes to land loss over 34 years in the Atchafalaya‐Vermillion, Terrebonne, and Barataria basins of the Mississippi Delta. Tracking the area changes in ponds on the marsh surface, we find a striking consistency between pond expansion direction and the dominant wind direction and show that wind‐generated waves are capable of causing edge erosion. Expansion rate increases rapidly for ponds wider than 300 m in Terrebonne and Barataria basins. From this, we suggest that ponds in Atchafalaya‐Vermillion basin are stable, whereas ponds in Terrebonne and Barataria are unstable.
One‐pot Synthesis of Oxindoles through C−H Alkylation and Intramolecular Cyclization of Azobenzenes with Internal Olefins
Authors: Han Sang Hoon , Mishra Neeraj Kumar , Jo Hyeim , Oh Yongguk , Jeon Mijin , Kim Saegun , Kim Woo Jung , Lee Jong Suk , Kim Hyung Sik , Kim In Su 
Published: April 2017

AbstractThe rhodium(III)‐catalyzed site‐selective C−H alkylation of azobenzenes and internal olefins, such as maleimides, maleates and fumarates, followed by reductive intramolecular cyclization is described. A cationic rhodium catalyst in the presence of acetic acid additive in dichloroethane solvent was found to be the optimal catalytic system for the construction of ortho‐alkylated azobenzenes, which smoothly underwent the intramolecular cyclization leading to the formation of C3‐functionalized oxindoles in the presence of zinc powder and acetic acid. The formed oxindole scaffold could be an important asset towards the development of novel bioactive compounds.magnified image
Palladium‐Catalyzed Synthesis of Tetrasubstituted Olefins by Triple Domino Process
Authors: Naveen Kanagaraj , Nikson Savariyappan Albert , Perumal Paramasivan Thirumalai 
Published: April 2017

AbstractAn efficient, highly regio‐ and stereoselective protocol for the synthesis of tetrasubstituted olefins was developed to take place by a palladium(0)‐catalyzed triple domino process. It involves the formation of three new C−C bonds through double carbopalladation and C−H activation across 2‐bromoaryl alkynyl biaryls/heteroaryls with norbornene. This method is practically simple with broad substrate scope and tolerates a wide range of substituents. The products bearing 9H‐pyrrolo[1,2‐a]indole motifs reveal intriguing solid state fluorescence properties and thus form a new class of aggregation induced emission (AIE) fluorophores.magnified image
Elastic bending and stress analysis of carbon nanotube‐reinforced composite plate: Experimental, numerical, and simulation
Authors: Mehar Kulmani , Panda Subrata Kumar 
Published: April 2017

AbstractThe deflection behavior of carbon nanotube‐reinforced composite plate is investigated numerically using the finite‐element method and the result accuracy is established via three‐point experimental bending test data. The physical composite panel model is realized with the help of new mathematical model based on the higher order kinematic theory and the responses are computed using the in‐house computer code in the MATLAB environment. Further, the efficacy of the current higher order finite‐element model has been established by comparing the deflection responses with those of the references, simulation values (ANSYS), and the in‐house experimentation including the experimental elastic properties. Finally, the effect of different design parameters, such as aspect ratio, thickness ratio, edge constraints including the types of load on the deflection and stress responses of the composite plate has been studied in detail.
Palladium(II) Bis(oxazoline) Complexes that Catalyze the Hydration of Alkynes
Authors: Kusakabe Taichi , Ito Yoichi , Kamimura Misato , Shirai Tsukasa , Takahashi Keisuke , Mochida Tomoyuki , Kato Keisuke 
Published: April 2017

AbstractThe hydration of alkynes catalyzed by palladium(II) bis(oxazoline) complexes is described. The corresponding ketones were obtained in good yields and no special additives were required.
Dental wear and age grading at Roonka, South Australia
Authors: Littleton Judith 
Published: April 2017

AbstractObjectivesIn many hunter‐gatherer populations, the teeth are used as a third hand or a tool. Much attention has been paid to wear and its relationship to gendered division of labor, but age is also a significant organizing factor in many societies. In this article, I analyze whether the pattern of wear at Roonka, Australia, reflects the age‐graded acquisition of tasks.Materials and MethodsThe remains analyzed come from Roonka and date from c6000 BP to 150 BP. In total 126 adults and juveniles were analyzed. Wear gradients were calculated for each tooth relative to wear on the first molar. Data were compared using nonparametric statistics and cluster analysis to assess the degree of patterning within the sample.ResultsDental wear proceeded rapidly. There is no evidence of sex differences in the pattern of wear. Age differences do occur. While disproportionate anterior wear occurs among juveniles and young adults, by middle adulthood the pattern is less variable and involves the premolars. Old adults have a much flatter pattern of wear.DiscussionThe pattern of wear is consistent with ethnographic observations, which suggest a degree of latitude in the activities of juveniles and young adults. By middle age variability between individuals declines reflecting shared tasks and more intensive use of the teeth. The pattern of wear amongst old adults, however, is much flatter presumably due to changes in occlusion. While dental wear is informative about the organization of labor there is a need to take into account both patterns of activity and occlusion.
Stabile Polyoxometallat‐Nickelschaum‐Elektroden für elektrochemische Sauerstoffentwicklung im alkalischen Milieu
Authors: Luo Wenjing , Hu Jun , Diao Hongling , Schwarz Benjamin , Streb Carsten , Song Yu‐Fei 
Published: April 2017

AbstractDie Entwicklung von technisch relevanten Elektroden für die elektrochemische Sauerstoffentwicklung (OER) ist eine der größten Herausforderungen der chemischen Energiewandlung. Nun gelang die hydrothermale Immobilisierung des Dexter‐Silverton‐Polyoxometallats, [Co6.8Ni1.2W12O42(OH)4(H2O)8], auf einer kommerziellen Nickelschaumelektrode. Im alkalischen Milieu (pH 13) zeigt das Elektrodenmaterial katalytische Sauerstoffentwicklung bei niedriger Überspannung (360 mV bei 10 mA cm−2 gegen RHE, Tafel‐Steigung 126 mV dec−1, Faraday‐Effizienz (96±5) %). Zudem ist keine Zersetzung oder Abtrennung der Polyoxometallat‐Mikrokristalle von der Elektrode nach der Katalyse zu beobachten. Die vorgestellte Immobilisierungsroute kann also einen Zugang zu technisch relevanten Elektrodenmaterialien für die Sauerstoffentwicklung eröffnen.
Characterization of Plasma Membrane Ceramides by Super‐Resolution Microscopy
Authors: Burgert Anne , Schlegel Jan , Bécam Jérôme , Doose Sören , Bieberich Erhard , Schubert‐Unkmeir Alexandra , Sauer Markus 
Published: April 2017

AbstractThe sphingolipid ceramide regulates cellular processes such as differentiation, proliferation, growth arrest, and apoptosis. Ceramide‐rich membrane areas promote structural changes within the plasma membrane that segregate membrane receptors and affect membrane curvature and vesicle formation, fusion, and trafficking. Ceramides were labeled by immunocytochemistry to visualize their distribution on the plasma membrane of different cells with virtually molecular resolution by direct stochastic optical reconstruction microscopy (dSTORM). Super‐resolution images show that independent of labeling conditions and cell type 50–60 % of all membrane ceramides are located in ceramide‐rich platforms (CRPs) with a size of about 75 nm that are composed of at least about 20 ceramides. Treatment of cells withBacillus cereussphingomyelinase (bSMase) increases the overall ceramide concentration in the plasma membrane, the quantity of CRPs, and their size. Simultaneously, the ceramide concentration in CRPs increases approximately twofold.
Four‐Component Synthesis of Phosphonium Salts: Application Toward an Alternative Approach to Cross‐Coupling for the Synthesis of Bis‐Heteroarenes
Authors: Chen Yi‐Ru , Reddy Ganapuram Madhusudhan , Hong Shao‐Hao , Wang Ying‐Zheng , Yu Jhen‐Kuei , Lin Wenwei 
Published: April 2017

AbstractA series of stable phosphonium salts have been synthesized via a novel four‐component reaction of an arene nucleophile, 2‐heteroatom substituted aryl aldehyde, and phosphine in presence of an acid. The phosphonium salts thus obtained were utilized for the synthesis of a variety of bis‐heteroarenes, providing an efficient alternative method to the classical cross‐coupling strategies.
Synthetic Glycoforms Reveal Carbohydrate‐Dependent Bioactivity of Human Saposin D
Authors: Graf Christopher G. F. , Schulz Christian , Schmälzlein Marina , Heinlein Christian , Mönnich Manuel , Perkams Lukas , Püttner Markus , Boos Irene , Hessefort Markus , Lombana Sanchez Jose Nelson , Weyand Michael , Steegborn Clemens , Breiden Bernadette , Ross Kerstin , Schwarzmann Günter , Sandhoff Konrad , Unverzagt Carlo 
Published: April 2017

AbstractThe main glycoforms of the hydrophobic lysosomal glycoprotein saposin D (SapD) were synthesized by native chemical ligation. An approach for the challenging solid‐phase synthesis of the fragments was developed. Three SapD glycoforms were obtained following a general and robust refolding and purification protocol. A crystal structure of one glycoform confirmed its native structure and disulfide pattern. Functional assays revealed that the lipid‐binding properties of three SapD glycoforms are highly affected by the single sugar moiety of SapD showing a dependency of the size and the type of N‐glycan.
Palladium‐Catalyzed Asymmetric Construction of Vicinal Tertiary and All‐Carbon Quaternary Stereocenters by Allylation of β‐Ketocarbonyls with Morita–Baylis–Hillman Adducts
Authors: Liu Jiawang , Han Zhaobin , Wang Xiaoming , Meng Fanye , Wang Zheng , Ding Kuiling 
Published: April 2017

AbstractPalladium‐catalyzed regio‐, diastereo‐, and enantioselective allylic alkylation of β‐ketocarbonyls with Morita–Baylis–Hillman adducts has been developed using a spiroketal‐based diphosphine (SKP) as the ligand, thus affording a range of densely functionalized products bearing vicinal tertiary and all‐carbon quaternary stereodyad in high selectivities. The utility of the protocol was demonstrated by the facile synthesis of some complex molecules by simple product transformations.
Spontaneous and Widespread Electricity Generation in Natural Deep‐Sea Hydrothermal Fields
Authors: Yamamoto Masahiro , Nakamura Ryuhei , Kasaya Takafumi , Kumagai Hidenori , Suzuki Katsuhiko , Takai Ken 
Published: April 2017

AbstractDeep‐sea hydrothermal vents discharge abundant reductive energy into oxidative seawater. Herein, we demonstrated that in situ measurements of redox potentials on the surfaces of active hydrothermal mineral deposits were more negative than the surrounding seawater potential, driving electrical current generation. We also demonstrated that negative potentials in the surface of minerals were widespread in the hydrothermal fields, regardless of the proximity to hydrothermal fluid discharges. Lab experiments verified that the negative potential of the mineral surface was induced by a distant electron transfer from the hydrothermal fluid through the metallic and catalytic properties of minerals. These results indicate that electric current is spontaneously and widely generated in natural mineral deposits in deep‐sea hydrothermal fields. Our discovery provides important insights into the microbial communities that are supported by extracellular electron transfer and the prebiotic chemical and metabolic evolution of the ocean hydrothermal systems.
Effects of biocide treatments on durability of wood and bamboo/high density polyethylene composites against algal and fungal decay
Authors: Feng Jing , Chen Juan , Chen Mingjie , Su Xiulin , Shi Qingshan 
Published: April 2017

ABSTRACTThe main objective of this study was to investigate the algal and fungal resistance of biocide‐treated wood flour (WF)/high density polyethylene (HDPE) and bamboo flour (BF)/HDPE composites. The biocides included 4,5‐dichloro‐2‐octyl‐isothiazolone (DCOIT), zinc pyrithione (ZPT), and carbendazim (MBC). Resistance to algae and fungi was evaluated by artificially accelerated tests. Treated and untreated samples were exposed to algae (Chlorella vulgaris, Ulothrix sp., Scenedesmus quadricauda, and Oscillatoria sp.) and fungi (Coriolus versicolor and Poria placenta) for 21 days and 12 weeks, respectively. The volatile components of WF and BF extractives were analyzed by gas chromatography‐mass spectrometry (GC‐MS). The results indicated that incorporation of DCOIT, ZPT, and MBC effectively enhanced the durability of WF/HDPE and BF/HDPE composites against algal and fungal decay. Accordingly, DCOIT, ZPT, and MBC can be used as potential biocides for both WF/HDPE and BF/HDPE composites. GC‐MS analysis suggested that palmitic acid, oleic acid, stigmasta‐3,5‐dien‐7‐one, and vanillin in WF possibly provided some resistance to fungal attack, whereas di (2‐ethylhexyl) phthalate and linoleic acid in BF were responsible for algal resistance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45148.
Demography of sea lamprey (Petromyzon marinus) ammocoete populations in relation to potential spawning‐migration obstructions
Authors: Nunn A. D. , Taylor R. J. , Cowx I. G. , Noble R. A. A. , Bolland J. D. , Harvey J. P. 
Published: April 2017

Abstract

Recent advances in the understanding of lamprey migrations have led to concerns over the impacts of obstructions on the demography of many species. This study investigated sea lamprey (Petromyzon marinus) larvae (ammocoetes) in two adjacent but contrasting rivers, both designated Special Areas of Conservation under the EC Habitats Directive (92/43/EEC), one (the River Wye) with a small number of potential migration obstructions in its upper reaches and one (the River Usk) with obstacles along its course. The geographical distributions, densities and age structures of the ammocoete populations were examined in relation to the locations of potential obstructions to the spawning migrations of anadromous adults.
A minimum of three age classes was recorded as far as 200 km upstream of the mouth of the River Wye (93% of the length of the mainstem), demonstrating that adults regularly migrate to the upper reaches of the catchment (downstream of a natural waterfall). By contrast, sea lamprey ammocoetes appeared to be absent (in suitable habitat) from 20 km (17%) of the River Usk, and there was a reduction in density, prevalence and the number of age classes upstream of two putative spawning‐migration obstructions.
This study highlights some of the potential impacts of habitat fragmentation by obstructions on the spawning migrations of anadromous species, as inferred from ammocoete demography. When used in combination to compare contiguous reaches, ammocoete densities, prevalence and age structure may be a useful indicator of which structures are likely to be important migration obstructions, and where further studies or mitigation efforts should be focused. It is likely that passage past some obstructions is enhanced if high river levels occur during the spawning migration, but there is a need to facilitate passage during all conditions, to improve access to under‐exploited spawning and nursery areas.