bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Sensitivity of North American Terrestrial Carbon Fluxes to Spatial and Temporal Variation in Soil Moisture: An Analysis Using Radar‐Derived Estimates of Root‐Zone Soil Moisture
Authors: Zhang Ke , Ali Ashehad , Antonarakis Alexander , Moghaddam Mahta , Saatchi Sassan , Tabatabaeenejad Alireza , Chen Richard , Jaruwatanadilok Sermsak , Cuenca Richard , Crow Wade T. , Moorcroft Paul 
Published: October 2019

AbstractThis study examines the impact of variation in root‐zone soil moisture (RZSM), a key component of the Earth's hydrologic cycle and climate system, on regional carbon fluxes across seven North American ecosystems. P‐band synthetic aperture radar‐derived RZSM estimates were incorporated into the ecosystem demography (ED2) terrestrial biosphere model through a model‐data blending approach. Analysis shows that the model qualitatively captures inter‐daily and seasonal variability of observed RZSM at seven flux tower sites (r = 0.59 ± 0.26 andr = 0.70 ± 0.22 for 0–10 and 10–40 cm of soil layers, respectively;P < 0.001). Incorporating the remotely sensed RSZM estimates increases the accuracy (root‐mean‐square deviations decrease from 0.10 ± 0.07 and 0.09 ± 0.06 m3·m−3to 0.08 ± 0.05 and 0.07 ± 0.03 m3·m−3for 0–10 and 10–40 cm of soil layers, respectively) of the model's RZSM predictions. The regional carbon fluxes predicted by the native and RZSM‐constrained model were used to quantify sensitivities of gross primary productivity, autotrophic respiration (Ra), heterotrophic respiration (Rh), and net ecosystem exchange to variation in RZSM. Gross primary productivity exhibited the largest sensitivity (6.6 ± 10.7 kg·cm−2·year·θ−1) followed by Ra(2.9 ± 7.3 kg·cm−2·year−1·θ−1), Rh(2.6 ± 3.1 kg·cm−2·year−1·θ−1), and net ecosystem exchange (−1.7 ± 7.8 kg·cm−2·year−1·θ−1). Analysis shows that these carbon flux sensitivities varied considerably across regions, reflecting influences of canopy structure, soil properties, and the ecophysiological properties of different plant functional types. This study highlights (1) the importance of improved terrestrial biosphere model predictions of RZSM to improve predictions of terrestrial carbon fluxes, (2) a need for improved pedotransfer functions, and (3) improved understanding of how soil characteristics, climate, and vegetation composition interact to govern the responses of different ecosystems to changing hydrological conditions.
Surface Stability in Drylands Is Influenced by Dispersal Strategy of Soil Bacteria
Authors: Elliott David R. , Thomas Andrew D. , Strong Craig L. , Bullard Joanna 
Published: October 2019

AbstractMicrobial adaptations for survival and dispersal may directly influence landscape stability and potential for dust emission in drylands where biological soil crusts (biocrusts) protect mineral soil surfaces from wind erosion. In the Lake Eyre basin of central Australia we operated a wind tunnel on sandy soils and collected the liberated material, which was subjected to DNA sequencing to identify the microbial community composition. Microbial composition of entrained dust was compared with that of the source sand dune soil in addition to nearby claypan and nebkha soils and water channels that together form a recycling sediment transport system. Wind was found to preferentially liberate 359 identified taxa from sand dunes, whereas 137 identified taxa were found to resist wind erosion. Water channel communities included many taxa in common with the soil samples. We hypothesize that the ease with which soil microbes become airborne is often linked to whether the organism is adapted for dispersal by wind or vegetative growth and that biocrust organisms found in water channels may sometimes use a fluvial dispersal strategy, which exploits rare flooding events to rapidly colonize vast pans that are common in drylands. We explain likely geomorphic implications of microbial dispersal strategies which are a consequence of organisms engineering the environment to provide their particular needs. By identifying microbes fitting expectations for these dispersal strategies based on differential abundance analyses, we provide a new perspective for understanding the role of microbiota in landscape stability.
On the Mechanisms of the Active 2018 Tropical Cyclone Season in the North Pacific
Authors: Qian Y. , Murakami H. , Nakano M. , Hsu P.‐C. , Delworth T. L. , Kapnick S. B. , Ramaswamy V. , Mochizuki T. , Morioka Y. , Doi T. , Kataoka T. , Nasuno T. , Yoshida K. 
Published: October 2019

AbstractThe 2018 tropical cyclone (TC) season in the North Pacific was very active, with 39 tropical storms including eight typhoons/hurricanes. This activity was successfully predicted up to 5 months in advance by the Geophysical Fluid Dynamics Laboratory Forecast‐Oriented Low Ocean Resolution (FLOR) global coupled model. In this work, a suite of idealized experiments with three dynamical global models (FLOR, Nonhydrostatic Icosahedral Atmospheric Model, and Meteorological Research Institute Atmospheric General Circulation Model) was used to show that the active 2018 TC season was primarily caused by warming in the subtropical Pacific and secondarily by warming in the tropical Pacific. Furthermore, the potential effect of anthropogenic forcing on the active 2018 TC season was investigated using two of the global models (FLOR and Meteorological Research Institute Atmospheric General Circulation Model). The models projected opposite signs for the changes in TC frequency in the North Pacific by an increase in anthropogenic forcing, thereby highlighting the substantial uncertainty and model dependence in the possible impact of anthropogenic forcing on Pacific TC activity.
Analysis of Cosmic Rays' Atmospheric Effects and Their Relationships to Cutoff Rigidity and Zenith Angle Using Global Muon Detector Network Data
Authors: Mendonça R. R. S. , Wang C. , Braga C. R. , Echer E. , Dal Lago A. , Costa J. E. R. , Munakata K. , Li H. , Liu Z. , Raulin J.‐P. , Kuwabara T. , Kozai M. , Kato C. , Rockenbach M. , Schuch N. J. , Al Jassar H. K. , Sharma M. M. , Tokumaru M. , Duldig M. L. , Humble J. E. , Evenson P. , Sabbah I. 
Published: October 2019

AbstractCosmic rays are charged particles whose flux observed at Earth shows temporal variations related to space weather phenomena and may be an important tool to study them. The cosmic ray intensity recorded with ground‐based detectors also shows temporal variations arising from atmospheric variations. In the case of muon detectors, the main atmospheric effects are related to pressure and temperature changes. In this work, we analyze both effects using data recorded by the Global Muon Detector Network, consisting of four multidirectional muon detectors at different locations, in the period between 2007 and 2016. For each Global Muon Detector Network directional channel, we obtain coefficients that describe the pressure and temperature effects. We then analyze how these coefficients can be related to the geomagnetic cutoff rigidity and zenith angle associated with cosmic ray particles observed by each channel. In the pressure effect analysis, we found that the observed barometric coefficients show a very clear logarithmic correlation with the cutoff rigidity divided by the zenith angle cosine. On the other hand, the temperature coefficients show a good logarithmic correlation with the product of the cutoff and zenith angle cosine after adding a term proportional to the sine of geographical latitude of the observation site. This additional term implies that the temperature effect measured in the Northern Hemisphere detectors is stronger than that observed in the Southern Hemisphere. The physical origin of this term and of the good correlations found in this analysis should be studied in detail in future works.
Relations Between the Characteristics of Granular Column Collapses and Resultant High‐Frequency Seismic Signals
Authors: Farin Maxime , Mangeney Anne , de Rosny Julien , Toussaint Renaud , Trinh Phuong‐Thu 
Published: October 2019

Deducing relations between the dynamic characteristics of landslides and rockfalls and the resultant high‐frequency (>1 Hz) seismic signal is challenging. To investigate relations that can be tested in the field, we conducted laboratory experiments of 3‐D granular column collapse on a rough inclined thin plate, for a large set of column masses, aspect ratios, particle diameters, and slope angles. The dynamics of the granular flows were recorded using a high‐speed camera, and the generated seismic signal was measured using piezoelectric accelerometers. Empirical scaling laws are established between the characteristics of the granular flows and deposits and that of the generated seismic signals. The radiated seismic energy scales with particle diameter as d3, column mass as M and aspect ratio as a1.1. The increase of the radiated seismic energy as slope angle increases correlates with a similar increase in particle agitation. Based on our experimental results, we revisit scaling laws reported in the field and discuss their possible physical origin. The discrepancy between field and experimental observations can be explained by the complex influence of the substrate on seismic signal and the difference of flow initiation in both cases. However, our empirical scaling laws allow us to determine which flow parameters could be inferred from a given seismic characteristic in the field. In particular, by assuming the flow average speed is known, we show that we can retrieve parameters d, M, and a within a factor of two from the seismic signal.
A Coupled Biomorpho‐Geomechanical Model of Tidal Marsh Evolution
Authors: Zoccarato C. , Da Lio C. , Tosi L. , Teatini Pietro 
Published: October 2019

AbstractEcogeomorphic characteristics of tidal marshes are strongly related to their elevation with respect to the mean sea level. Predicting the long‐term evolution and resilience of such ecosystems in times of rapid natural and anthropogenic climate changes is of critical importance. The notion that the tidal marsh elevation is the result of feedbacks between vegetation dynamics, sediment fluxes, natural consolidation, and sea‐level changes is widely recognized. However, the interaction of these processes has been poorly investigated until now. This contribution aims at presenting a novel numerical model to simulate the above‐surface and subsurface coupled dynamics of a tidal landscape in a 2‐D‐framework, with the relative sea‐level rise (RSLR) acting as an external stressor. A biomorphological model is used to compute deposition fluxes, which depends on topography and availability of organic/inorganic sediments. The outcome is used as forcing term in a physically based geomechanical model to simulate the consolidation of the marsh body that, in turn, influences sediment fluxes by acting on the platform elevation. The results demonstrate how compaction of the marsh body can crucially affect the resilience of tidal landforms to RSLR accelerations. With normal sediment concentration in coastal waters (10<C0<100 mg/l), if minerogenic (stiff) deposits prevail, a tidal marsh is capable of maintaining its elevation relative to mean sea level independently of RSLR (at least up to 10 mm/yr). When the marsh is composed of a large percentage of more compressible organic matter, the landform resilience is much more dependent on RSLR, implying higher vulnerability with respect to future climate changes.
The crosstalk between STAT3 and p53/RAS signaling controls cancer cell metastasis and cisplatin resistance via the Slug/MAPK/PI3K/AKT-mediated regulation of EMT and autophagy
Authors: Liang Fan , Ren Chunxia , Wang Jingshu , Wang Shuoer , Yang Lina , Han Xianghui , Chen Yaping , Tong Guoqing , Yang Gong 
Published: October 2019

AbstractChemoresistance has been the biggest obstacle in ovarian cancer treatment, and STAT3 may play an important role in chemoresistance of multiple cancers, but the underlying mechanism of STAT3 in ovarian cancer chemoresistance has long been truly illusive, particularly in association with p53 and RAS signaling. In this study, by using wild type, constitutive active, and dominant negative STAT3 constructs, wild-type p53, and RAS-mutant V12, we performed a series of in vitro and in vivo experiments by gene overexpression, drug treatment, and animal assays. We found that phosphorylation of STAT3 Y705 but not S727 promoted cancer cell EMT and metastasis through the Slug-mediated regulation of E-cadherin and Vimentin. The phosphorylation of STAT3 at Y705 also activated the MAPK and PI3K/AKT signaling to inhibit the ERS-mediated autophagy through down-regulation of pPERK, pelf2α, ATF6α, and IRE1α, which led to increased cisplatin resistance. Induction of wild type p53 in STAT3-DN-transfected cells further diminished the chemoresistance and tumor growth through the upregulation of the MAPK- and PI3K/AKT-mediated ERS and autophagy. Introduction of STAT3-DN deprived the RASV12-induced ERS, autophagy, oncogenicity, and cisplatin resistance, whereas introduction of p53 in STAT3-DN/RASV12 expressing cells induced additional tumor retardation and cisplatin sensitivity. Thus, our data provide strong evidence that the crosstalk between STAT3 and p53/RAS signaling controls ovarian cancer cell metastasis and cisplatin resistance via the Slug/MAPK/PI3K/AKT-mediated regulation of EMT and autophagy.
Reconfiguration of interfacial energy band structure for high-performance inverted structure perovskite solar cells
Authors: Zhang Moyao , Chen Qi , Xue Rongming , Zhan Yu , Wang Cheng , Lai Junqi , Yang Jin , Lin Hongzhen , Yao Jianlin , Li Yaowen , Chen Liwei , Li Yongfang 
Published: October 2019

AbstractCharged defects at the surface of the organic–inorganic perovskite active layer are detrimental to solar cells due to exacerbated charge carrier recombination. Here we show that charged surface defects can be benign after passivation and further exploited for reconfiguration of interfacial energy band structure. Based on the electrostatic interaction between oppositely charged ions, Lewis-acid-featured fullerene skeleton after iodide ionization (PCBB-3N-3I) not only efficiently passivates positively charged surface defects but also assembles on top of the perovskite active layer with preferred orientation. Consequently, PCBB-3N-3I with a strong molecular electric dipole forms a dipole interlayer to reconfigure interfacial energy band structure, leading to enhanced built-in potential and charge collection. As a result, inverted structure planar heterojunction perovskite solar cells exhibit the promising power conversion efficiency of 21.1% and robust ambient stability. This work opens up a new window to boost perovskite solar cells via rational exploitation of charged defects beyond passivation.
Extracellular Vesicles Shedding Promotes Melanoma Growth in Response to Chemotherapy
Authors: Andrade Luciana Nogueira de Sousa , Otake Andréia Hanada , Cardim Silvia Guedes Braga , da Silva Felipe Ilelis , Ikoma Sakamoto Mariana Mari , Furuya Tatiane Katsue , Uno Miyuki , Pasini Fátima Solange , Chammas Roger 
Published: October 2019

AbstractExtracellular vesicles (EVs) are emerging as key players in intercellular communication. EVs can transfer biological macromolecules to recipient cells, modulating various physiological and pathological processes. It has been shown that tumor cells secrete large amounts of EVs that can be taken up by malignant and stromal cells, dictating tumor progression. In this study, we investigated whether EVs secreted by melanoma cells in response to chemotherapy modulate tumor response to alkylating drugs. Our findings showed that human and murine melanoma cells secrete more EVs after treatment with temozolomide and cisplatin. We observed that EVs shed by melanoma cells after temozolomide treatment modify macrophage phenotype by skewing macrophage activation towards the M2 phenotype through upregulation of M2-marker genes. Moreover, these EVs were able to favor melanoma re-growth in vivo, which was accompanied by an increase in Arginase 1 and IL10 gene expression levels by stromal cells and an increase in genes related to DNA repair, cell survival and stemness in tumor cells. Taken together, this study suggests that EVs shed by tumor cells in response to chemotherapy promote tumor repopulation and treatment failure through cellular reprogramming in melanoma cells.
Distinctive mutational spectrum and karyotype disruption in long-term cisplatin-treated urothelial carcinoma cell lines
Authors: Skowron Margaretha A. , Petzsch Patrick , Hardt Karin , Wagner Nicholas , Beier Manfred , Stepanow Stefanie , Drechsler Matthias , Rieder Harald , Köhrer Karl , Niegisch Günter , Hoffmann Michèle J. , Schulz Wolfgang A. 
Published: October 2019

AbstractThe DNA-damaging compound cisplatin is broadly employed for cancer chemotherapy. The mutagenic effects of cisplatin on cancer cell genomes are poorly studied and might even contribute to drug resistance. We have therefore analyzed mutations and chromosomal alterations in four cisplatin-resistant bladder cancer cell lines (LTTs) by whole-exome-sequencing and array-CGH. 720–7479 genes in the LTTs contained point mutations, with a characteristic mutational signature. Only 53 genes were mutated in all LTTs, including the presumed cisplatin exporter ATP7B. Chromosomal alterations were characterized by segmented deletions and gains leading to severely altered karyotypes. The few chromosomal changes shared among LTTs included gains involving the anti-apoptotic BCL2L1 gene and losses involving the NRF2 regulator KEAP1. Overall, the extent of genomic changes paralleled cisplatin treatment concentrations. In conclusion, bladder cancer cell lines selected for cisplatin-resistance contain abundant and characteristic drug-induced genomic changes. Cisplatin treatment may therefore generate novel tumor genomes during patient treatment.
Tuning the Electrical and Thermoelectric Properties of N Ion Implanted SrTiO3 Thin Films and Their Conduction Mechanisms
Authors: Bhogra Anuradha , Masarrat Anha , Meena Ramcharan , Hasina Dilruba , Bala Manju , Dong Chung-Li , Chen Chi-Liang , Som Tapobrata , Kumar Ashish , Kandasami Asokan 
Published: October 2019

AbstractThe SrTiO3 thin films were fabricated by pulsed laser deposition. Subsequently ion implantation with 60 keV N ions at two different fluences 1 × 1016 and 5 × 1016 ions/cm2 and followed by annealing was carried out. Thin films were then characterized for electronic structure, morphology and transport properties. X-ray absorption spectroscopy reveals the local distortion of TiO6 octahedra and introduction of oxygen vacancies due to N implantation. The electrical and thermoelectric properties of these films were measured as a function of temperature to understand the conduction and scattering mechanisms. It is observed that the electrical conductivity and Seebeck coefficient (S) of these films are significantly enhanced for higher N ion fluence. The temperature dependent electrical resistivity has been analysed in the temperature range of 80–400 K, using various conduction mechanisms and fitted with band conduction, near neighbour hopping (NNH) and variable range hopping (VRH) models. It is revealed that the band conduction mechanism dominates at high temperature regime and in low temperature regime, there is a crossover between NNH and VRH. The S has been analysed using the relaxation time approximation model and dispersive transport mechanism in the temperature range of 300–400 K. Due to improvement in electrical conductivity and thermopower, the power factor is enhanced to 15 µWm−1 K−2 at 400 K at the higher ion fluence which is in the order of ten times higher as compared to the pristine films. This study suggests that ion beam can be used as an effective technique to selectively alter the electrical transport properties of oxide thermoelectric materials.
Vulnerability to climate change of islands worldwide and its impact on the tree of life
Authors: Veron Simon , Mouchet Maud , Govaerts Rafaël , Haevermans Thomas , Pellens Roseli 
Published: October 2019

AbstractIsland systems are among the most vulnerable to climate change, which is predicted to induce shifts in temperature, rainfall and/or sea levels. Our aim was: (i) to map the relative vulnerability of islands to each of these threats from climate change on a worldwide scale; (ii) to estimate how island vulnerability would impact phylogenetic diversity. We focused on monocotyledons, a major group of flowering plants that includes taxa of important economic value such as palms, grasses, bananas, taro. Islands that were vulnerable to climate change were found at all latitudes, e.g. in Australia, Indonesia, the Caribbean, Pacific countries, the United States, although they were more common near the equator. The loss of highly vulnerable islands would lead to relatively low absolute loss of plant phylogenetic diversity. However, these losses tended to be higher than expected by chance alone even in some highly vulnerable insular systems. This suggests the possible collapse of deep and long branches in vulnerable islands. Measuring the vulnerability of each island is a first step towards a risk analysis to identify where the impacts of climate change are the most likely and what may be their consequences on biodiversity.
Effect of the solar wind density on the evolution of normal and inverse coronal mass ejections
Authors: Hosteaux S. , Chané E. , Poedts S. 
Published: October 2019

Context. The evolution of magnetised coronal mass ejections (CMEs) and their interaction with the background solar wind leading to deflection, deformation, and erosion is still largely unclear as there is very little observational data available. Even so, this evolution is very important for the geo-effectiveness of CMEs.
Aims. We investigate the evolution of both normal and inverse CMEs ejected at different initial velocities, and observe the effect of the background wind density and their magnetic polarity on their evolution up to 1 AU.
Methods. We performed 2.5D (axisymmetric) simulations by solving the magnetohydrodynamic equations on a radially stretched grid, employing a block-based adaptive mesh refinement scheme based on a density threshold to achieve high resolution following the evolution of the magnetic clouds and the leading bow shocks. All the simulations discussed in the present paper were performed using the same initial grid and numerical methods.
Results. The polarity of the internal magnetic field of the CME has a substantial effect on its propagation velocity and on its deformation and erosion during its evolution towards Earth. We quantified the effects of the polarity of the internal magnetic field of the CMEs and of the density of the background solar wind on the arrival times of the shock front and the magnetic cloud. We determined the positions and propagation velocities of the magnetic clouds and thus also the stand-off distance of the leading shock fronts (i.e. the thickness of the magnetic sheath region) and the deformation and erosion of the magnetic clouds during their evolution from the Sun to the Earth. Inverse CMEs were found to be faster than normal CMEs ejected in the same initial conditions, but with smaller stand-off distances. They also have a higher magnetic cloud length, opening angle, and mass. Synthetic satellite time series showed that the shock magnitude is not affected by the polarity of the CME. However, the density peak of the magnetic cloud is dependent on the polarity and, in case of inverse CMEs, also on the background wind density. The magnitude of the z-component of the magnetic field was not influenced by either the polarity or the wind density.