bluuebunny/crossref_metadata_2025_split huggingface dataset:
Emigración y remesas: un perfil para Chalatenango
Authors: Cartagena Edgar R. 
Published: February 2018

Emigration and economic remittances are key aspects in order to understand the socio-economic situation of El Salvador. This problem is analysed through the experience of Chalatenango, one of the most damaged zones of the country during the war of the eighties and one of the most poor regions in El Salvador.Realidad: Revista de Ciencias Sociales y Humanidades No. 105, 2005: 399-425
In Situ Observations of a Magnetosheath High‐Speed Jet Triggering Magnetopause Reconnection
Authors: Hietala H. , Phan T. D. , Angelopoulos V. , Oieroset M. , Archer M. O. , Karlsson T. , Plaschke F. 
Published: February 2018

AbstractMagnetosheath high‐speed jets—localized dynamic pressure enhancements typically of ∼1 Earth radius in size—impact the dayside magnetopause several times per hour. Here we present the first in situ measurements suggesting that such an impact triggered magnetopause reconnection. We use observations from the five Time History of Events and Macroscale Interactions during Substorms spacecraft in a string‐of‐pearls configuration on 7 August 2007. The spacecraft recorded magnetopause in‐and‐out motion during an impact of a magnetosheath jet (VN∼−300 km/s along the magnetopause normal direction). There was no evidence for reconnection for the preimpact crossing, yet three probes observed reconnection after the impact. We infer that the jet impact compressed the originally thick (60–70 di), high magnetic shear (140–160° magnetopause until it was thin enough for reconnection to occur. Magnetosheath high‐speed jets could therefore act as a driver for bursty dayside reconnection.
Aeolian Sand Transport in Out‐of‐Equilibrium Regimes
Authors: Selmani H. , Valance A. , Ould El Moctar A. , Dupont P. , Zegadi R. 
Published: February 2018

AbstractWe investigate the relaxation process toward the equilibrium regime of saltation transport in the context of nonuniform conditions. Relaxation phenomena can be described in terms of a characteristic length scale that measures the distance for the particle flux to adapt to a spatial change in flow or boundary conditions. We conducted wind tunnel experiments to document the influence of the upwind mass flux on the relaxation process. For zero upwind mass flux conditions, the relaxation process is monotone and the relaxation length is independent of the wind strength. In contrast, for nonzero upwind flux conditions (obtained by releasing particles in the flow from a finite height), the relaxation process is nonmonotone and is well captured by damped harmonic oscillations. Importantly, the relaxation length increases with increasing air flow velocity but is almost insensitive to the magnitude of the upwind flux. Our experimental outcomes clearly indicate that the relaxation of far from equilibrium transport regimes strongly deviates from a simple exponential behavior.
Weak Vertical Surface Movement Caused by the Ascent of the Emeishan Mantle Anomaly
Authors: Zhu Jiang , Zhang Zhaochong , Reichow Marc K. , Li Hongbo , Cai Wenchang , Pan Ronghao 
Published: February 2018

AbstractPrevailing mantle plume models reveal that the roles of plume‐lithosphere interactions in shaping surface topography are complex and controversial, and also difficult to test. The exposed and complete strata in the Emeishan large igneous province (LIP) recorded abundant paleoenvironmental information associated with preeruptions and syneruptions, attracting numerous workers to this province to test these models. Despite intensified research these models are still strongly debated. This study represents an extensive field investigation combining new and previously published data from the Emeishan LIP to further seek information on plume‐induced topographic variations. Our results indicate that there are inconspicuous vertical motions of the surface topography during the ascent of mantle plume, and a significant surface subsidence occurred at the early stage of the volcanism that has a significantly positive correlation with the thickness of local lavas, and the topographic uplift emerged in the late stage of the volcanism. Our studies provide key geological and geochemical evidence that the ascent of the Emeishan plume is unable to drive a significant surface uplift, owing to the plume containing numerous entrained bodies of dense recycled oceanic crust (10–20%) that can significantly reduce plume buoyancy. The significant surface subsidence maybe linked to a significant loss of thermal buoyancy due to the release of heat, which, accompanied by rapid loading of numerous dense erupted lava and a strong lithospheric flexure, also lead to a later synchronous and significant surface subsidence in the Emeishan LIP.
High‐Resolution Mapping of Yield Curve Shape and Evolution for Porous Rock: The Effect of Inelastic Compaction on Porous Bassanite
Authors: Bedford John D. , Faulkner Daniel R. , Leclère Henri , Wheeler John 
Published: February 2018

AbstractPorous rock deformation has important implications for fluid flow in a range of crustal settings as compaction can increase fluid pressure and alter permeability. The onset of inelastic strain for porous materials is typically defined by a yield curve plotted in differential stress (Q) versus effective mean stress (P) space. Empirical studies have shown that these curves are broadly elliptical in shape. Here conventional triaxial experiments are first performed to document (a) the yield curve of porous bassanite (porosity ≈ 27–28%), a material formed from the dehydration of gypsum, and (b) the postyield behavior, assuming that P and Q track along the yield surface as inelastic deformation accumulates. The data reveal that after initial yield, the yield surface cannot be perfectly elliptical and must evolve significantly as inelastic strain is accumulated. To investigate this further, a novel stress‐probing methodology is developed to map precisely the yield curve shape and subsequent evolution for a single sample. These measurements confirm that the high‐pressure side of the curve is partly composed of a near‐vertical limb. Yield curve evolution is shown to be dependent on the nature of the loading path. Bassanite compacted under differential stress develops a heterogeneous microstructure and has a yield curve with a peak that is almost double that of an equal porosity sample that has been compacted hydrostatically. The dramatic effect of different loading histories on the strength of porous bassanite highlights the importance of understanding the associated microstructural controls on the nature of inelastic deformation in porous rock.
Deciphering the State of the Late Miocene to Early Pliocene Equatorial Pacific
Authors: Drury A. J. , Lee G. P. , Gray W. R. , Lyle M. , Westerhold T. , Shevenell A. E. , John C. M. 
Published: February 2018

AbstractThe late Miocene‐early Pliocene was a time of global cooling and the development of modern meridional thermal gradients. Equatorial Pacific sea surface conditions potentially played an important role in this global climate transition, but their evolution is poorly understood. Here we present the first continuous late Miocene‐early Pliocene (8.0–4.4 Ma) planktic foraminiferal stable isotope records from eastern equatorial Pacific Integrated Ocean Drilling Program Site U1338, with a new astrochronology spanning 8.0–3.5 Ma. Mg/Ca analyses on surface dwelling foraminifera Trilobatus sacculifer from carefully selected samples suggest that mean sea surface temperatures (SSTs) are ~27.8 ± 1.1°C (1σ) between 6.4 and 5.5 Ma. The planktic foraminiferal δ18O record implies a 2°C cooling between 7.2 and 6.1 Ma and an up to 3°C warming between 6.1 and 4.4 Ma, consistent with observed tropical alkenone paleo‐SSTs. Diverging fine‐fraction‐to‐foraminiferal δ13C gradients likely suggest increased upwelling between 7.1–6.0 and 5.8–4.6 Ma, concurrent with the globally recognized late Miocene Biogenic Bloom. This study shows that both warm and asymmetric mean states occurred in the equatorial Pacific during the late Miocene‐early Pliocene. Between 8.0–6.5 and 5.2–4.4 Ma, low east‐west δ18O and SST gradients and generally warm conditions prevailed. However, an asymmetric mean climate state developed between 6.5 and 5.7 Ma, with larger east‐west δ18O and SST gradients and eastern equatorial Pacific cooling. The asymmetric mean state suggests stronger trade winds developed, driven by increased meridional thermal gradients associated with global cooling and declining atmospheric pCO2 concentrations. These oscillations in equatorial Pacific mean state are reinforced by Antarctic cryosphere expansion and related changes in oceanic gateways (e.g., Central American Seaway/Indonesian Throughflow restriction).
Tectonic Analysis of the Pennsylvanian Ely‐Bird Spring Basin: Late Paleozoic Tectonism on the Southwestern Laurentia Margin and the Distal Limit of the Ancestral Rocky Mountains
Authors: Sturmer D. M. , Trexler J. H. , Cashman P. H. 
Published: February 2018

AbstractDuring Pennsylvanian to Early Permian time, much of southwestern Laurentia experienced broad deformation far from the nearest plate boundaries. The bulk of this deformation is known as the Ancestral Rocky Mountains orogeny, which consists of several basement uplifts and proximal basins north and northwest of the Ouachita‐Marathon suture. The Ely‐Bird Spring basin formed during this time, located between the classic Ancestral Rocky Mountains and the complex and poorly constrained western Laurentian margin. In this study, we used tectonic subsidence curve analyses to evaluate the tectonic style of basin subsidence in this basin and several northern Ancestral Rocky Mountains basins. The Ely‐Bird Spring and Wood River basins have convex upward and stair‐stepped tectonic subsidence curves similar to curves from migrating foreland basins. These curves, combined with sedimentological and structural data, are consistent with these basins forming due to loading from the west and northwest as part of the complex western Laurentian plate boundary, not due to classic Ancestral Rocky Mountains tectonics. The other northern Ancestral Rocky Mountains basins have much steeper and more linear subsidence curves, similar to foreland basins with fixed loads. However, the Oquirrh basin, in particular, displays a large amount of subsidence far from hypothesized tectonic drivers of deformation. A combination of transmitted stress from both the western Laurentia margin and traditional Ancestral Rocky Mountains tectonism explains the anomalously large subsidence in the Oquirrh basin. Therefore, transmitted stresses from more than one side of western and southern Laurentia are required to explain the observed pattern of deformation.
Artificial Micro/Nanomachines for Bioapplications: Biochemical Delivery and Diagnostic Sensing
Authors: Kim Kwanoh , Guo Jianhe , Liang Zexi , Fan Donglei 
Published: February 2018

AbstractRecent progress in artificial nanomachines offers promising solutions to grand challenges in biochemical delivery and diagnostics. In this work, advances of micro/nanomachines made of synthesized micro/nanostructures for applications in delivery and detection of biomolecules are reviewed, along with a discussion of pros and cons of each type of machine. The review of micro/nanomachines is categorized according to their working mechanisms, including motion actuation realized by magnetic, electric, and acoustic fields and chemical reactions. The developments of micro/nanomachines are discussed in depth in the fabrication, propulsion, and motion control, loading and releasing of micro/nanosubstances, and biochemical sensing. The rapid development of man‐made miniaturized machines paves the road toward future intelligent nanorobots and nanofactories that can revolutionize society.
Ynesulfonamide‐Based Silica Gel and Alumina‐Mediated Diastereoselective Cascade Cyclizations to Spiro[indoline‐3,3′‐pyrrolidin]‐2‐ones under Neat Conditions
Authors: Wang Yanshi , Wang Xiaoyu , Lin Jingsheng , Yao Bo , Wang Guanghui , Zhao Yuandong , Zhang Xinhang , Lin Bin , Liu Yang , Cheng Maosheng , Liu Yongxiang 
Published: February 2018

AbstractThe spiro[indoline‐3,3′‐pyrrolidin]‐2‐ones were synthesized via a silica gel and alumina‐mediated sequential transformation based on tryptamine‐derived ynesulfonamide substrates under neat conditions. The inherent tendency of C−C bond migration through Wagner‐Meerwein rearrangement in the synthesis of spirooxindole was prevented by water trapping to the spiroindoleninium intermediate. The functional group tolerances of the methodology were investigated using a variety of substrates. The detailed mechanism of the sequential transformation was probed by the isotope‐labeled experiments. This strategy was further applied in the formal syntheses of indole alkaloids coerulescine and horsfiline.magnified image
Facile Intramolecular Cyclization of N‐(2‐Hydroxybenzoyl)hydrazones to N,N′‐Diacetyl Benzo‐1,3,4‐oxadiazepine Derivatives
Authors: Chan Pei Qie , Lee Yean Kee , Rahman Noorsaadah Abd. 
Published: February 2018

AbstractA facile synthesis of seven‐membered benzo‐1,3,4‐oxadiazepines through one‐step intramolecular cyclization of N‐(2‐hydroxybenzoyl)hydrazones has been established. The catalytic and substituent effects on the reactivity of this intramolecular cyclization were investigated. Through this strategy, a series of benzo‐1,3,4‐oxadiazepine derivatives were prepared (with yields up to 83 %).
Influence of the location of nasal polyps on olfactory airflow and olfaction
Authors: Nishijima Hironobu , Kondo Kenji , Yamamoto Takahisa , Nomura Tsutomu , Kikuta Shu , Shimizu Yuya , Mizushima Yu , Yamasoba Tatsuya 
Published: February 2018

BackgroundChronic rhinosinusitis with nasal polyps (CRSwNP) often results in decreased olfaction. In this study, we examined the relationship between nasal polyp location and olfactory airflow and odorant transport changes using virtual nasal polyp models at different locations and computational fluid dynamics (CFD) analysis. We also compared olfactory airflow and olfaction between patients with nasal polyps at different locations using CFD analysis and an olfactory test.MethodsNasal computed tomography images were used to generate a normal model and 4 virtual nasal polyp models based on polyp locations, including the olfactory region (all‐olfactory model), the region anterior to the olfactory region (preolfactory model), the middle meatus (middle‐meatus model), and the superior meatus (superior‐meatus model). Various airflow parameters were compared between these models and a normal model without polyps. We then performed a similar comparison between the 3‐dimensional (3D) reconstruction models of patients with nasal polyps, and retrospectively investigated the correlation between olfaction and nasal polyp location in those patients.ResultsVirtual nasal polyp analysis revealed dispersion of olfactory airflow in the all‐olfactory model. Olfactory airflow and odorant transport showed maximum decrease in the preolfactory model and a slight decrease in the superior‐meatus model. Olfactory airflow by polyps was further decreased by blockade of the olfactory airflow inlet than of the outlet. The findings obtained by patients corresponded well to those of the virtual polyp analysis.ConclusionOlfactory airflow and olfaction are differentially affected by nasal polyp location. This finding is important for planning polyp‐removal surgeries from the perspective of improving patient olfaction.
Covalent Triazine‐based Frameworks—Tailor‐made Catalysts and Catalyst Supports for Molecular and Nanoparticulate Species
Authors: Artz Jens 
Published: February 2018

AbstractThe quest for active, selective and stable catalysts for various applications has led researchers worldwide to investigate several combinations of molecular and solid catalyst systems. Solid molecular catalysts are considered to combine selectivity and reactivity of the molecular species with facile handling and good stability of the heterogeneous counterpart. Among other nanoporous polymers, covalent triazine‐based frameworks (CTFs) exhibit great potential as supports for both molecular as well as nanoparticulate species. Their high chemical and thermal stability in combination with tunable functionality to imbed active sites make them promising candidates to bridge the gap between homogeneous and heterogeneous catalysis. This Minireview seeks to outline the most recent developments in order to amplify research efforts within this fascinating and fast emerging field of material design and application. Emphasis is placed on the most recent advances in the following fields: Synthesis approaches and characteristics of CTFs, solid molecular catalysts and metal nanoparticles supported on CTFs as well as current challenges.
A Soft‐Elastic Reactor Inspired by the Animal Upper Digestion Tract
Authors: Liu Minghui , Xiao Jie , Chen Xiao Dong 
Published: February 2018

AbstractA soft‐elastic reactor is described, which was inspired by the animal upper digestion tract. The mixing is triggered by wall movements. Silicone material was selected based on previous experiences and conditioned into a standard cylindrical shape. Mixing was induced by the wall deformation triggered by the peristaltic movement, i.e., periodic protrusion towards the wall. Viscous glycerin solution served as sample material and a tracer was added to visualize the mechanisms of mixing. The fluid motion initiated by the soft‐elastic wall movement could be an interesting alternative to stirrer agitation. Pros and Cons are briefly highlighted. Due to the abundance of industrial soft‐elastic materials such as silicone, it is expected that, inspired by the soft reactors, a series of inventions in chemical reactor engineering will be offered in the near future.
Correlation between Liquid Product Distribution and H2 Selectivity in Lignin Depolymerization
Authors: Yang Jing , Liu Shaotong , Liu Chunze , Wang Yuanyuan , Dai Liyi 
Published: February 2018

AbstractDespite the vast potential for the depolymerization of kraft lignin in supercritical systems, selective access to desired renewable products remains a very challenging target. Catalytic depolymerization of kraft lignin was carried out in an isopropanol‐water mixture system over a Rh/La2O3/CeO2‐ZrO2 catalyst. The H2 selectivity was adjusted by changing the proportions of isopropanol and water. The introduction of formic acid was more helpful to extend the selectivity range. A correlation was established between liquid product distribution and H2 selectivity. It was used for predicting the composition of the liquid oil by H2 selectivity or, optionally, for converting kraft lignin to the desired liquid products. This correlation was applicable to different solvents, temperatures, and catalysts.
Urbanization disrupts latitude‐size rule in 17‐year cicadas
Authors: Beasley DeAnna E. , Penick Clint A. , Boateng Nana S. , Menninger Holly L. , Dunn Robert R. 
Published: February 2018

AbstractMany ectotherms show a decrease in body size with increasing latitude due to changes in climate, a pattern termed converse Bergmann's rule. Urban conditions—particularly warmer temperatures and fragmented landscapes—may impose stresses on development that could disrupt these body size patterns. To test the impact of urbanization on development and latitudinal trends in body size, we launched a citizen science project to collect periodical cicadas (Magicicada septendecim) from across their latitudinal range during the 2013 emergence of BroodII. Periodical cicadas are long‐lived insects whose distribution spans a broad latitudinal range covering both urban and rural habitats. We used a geometric morphometric approach to assess body size and developmental stress based on fluctuating asymmetry in wing shape. Body size of rural cicadas followed converse Bergmann's rule, but this pattern was disrupted in urban habitats. In the north, urban cicadas were larger than their rural counterparts, while southern populations showed little variation in body size between habitats. We detected no evidence of differences in developmental stress due to urbanization. To our knowledge, this is the first evidence that urbanization disrupts biogeographical trends in body size, and this pattern highlights how the effects of urbanization may differ over a species’ range.
Electrical and Mechanical Properties of Zirconia Based Cubic/Tetragonal Composite Electrolytes Prepared by Solution Coating Method
Authors: Ghatee M. 
Published: February 2018

AbstractIn this study, cubic/tetragonal zirconia based composite electrolytes were prepared by coating of 8YSZ powders with zirconia. At first zirconia solution was prepared and coated over the surface of 8YSZ(8 mol.% yttria stabilized zirconia) powders. The resulting powders then were formed into cylindrical specimens and sintered at various temperatures. Microstructure and phase content of samples were characterized by scanning electron microscopy (SEM) and X‐ray diffraction (XRD) techniques, respectively. The electrical conductivity of composite samples was studied by electrochemical impedance spectroscopy. In addition, hardness, toughness and fracture strength of samples were measured by Vickers microhardness indentation and ring on ring test, respectively. It was found that the homogeneous tetragonal/cubic composite electrolytes with improved electrical and mechanical properties at low temperatures can be obtained by this method.
Copper efflux transporters ATP7A and ATP7B: Novel biomarkers for platinum drug resistance and targets for therapy
Authors: Li Yue‐Qin , Yin Ji‐Ye , Liu Zhao‐Qian , Li Xiang‐Ping 
Published: February 2018

AbstractPlatinum‐based chemotherapy agents are widely used in the treatment of various solid malignancies. However, their efficacy is limited by drug resistance. Recent studies suggest that copper efflux transporters, which are encoded by ATP7A and ATP7B, play an important role in platinum drug resistance. Over‐expressions of ATP7A and ATP7B are observed in multiple cancers. Moreover, their expressions are associated with cancer prognosis and treatment outcomes of platinum‐based chemotherapy. In our review, we highlight the roles of ATP7A/7B in platinum drug resistance and cancer progression. We also discuss the possible mechanisms of platinum drug resistance mediated by ATP7A/7B and provide novel strategies for overcoming resistance. This review may be helpful for understanding the roles of ATP7A and ATP7B in platinum drug resistance. © 2018 IUBMB Life, 70(3):183–191, 2018