bluuebunny/crossref_metadata_2025_split huggingface dataset:
Drivers of Firn Density on the Greenland Ice Sheet Revealed by Weather Station Observations and Modeling
Authors: Vandecrux B. , Fausto R. S. , Langen P. L. , van As D. , MacFerrin M. , Colgan W. T. , Ingeman‐Nielsen T. , Steffen K. , Jensen N. S. , Møller M. T. , Box J. E. 
Published: September 2018

AbstractRecent Arctic atmospheric warming induces more frequent surface melt in the accumulation area of the Greenland ice sheet. This increased melting modifies the near‐surface firn structure and density and may reduce the firn's capacity to retain meltwater. Yet few long‐term observational records are available to determine the evolution and drivers of firn density. In this study, we compile and gap‐fill Greenland Climate Network (GC‐Net) automatic weather station data from Crawford Point, Dye‐2, NASA‐SE, and Summit between 1998 and 2015. These records then force a coupled surface energy balance and firn evolution model. We find at all sites except Summit that increasing summer turbulent heat fluxes to the surface are compensated by decreasing net radiative fluxes. After evaluating the model against firn cores, we find that, starting from 2006, the density of the top 20 m of firn at Dye‐2 increased by 11%, decreasing the pore volume by 18%. Crawford Point and Summit show stable near‐surface firn density over 1998–2010 and 2000–2015 respectively, while we calculate a 4% decrease of firn density at NASA‐SE over 1998–2015. For each year, the model identifies the drivers of density change in the top 20‐m firn and quantifies their contributions. The key driver, snowfall, explains alone 72 to 92% of the variance in day‐to‐day change in firn density while melt explains from 7 to 33%. Our result indicates that correct estimates of the magnitude and variability of precipitation are necessary to interpret or simulate the evolution of the firn.
The Morphology of the Tasmantid Seamounts: Interactions Between Tectonic Inheritance and Magmatic Evolution
Authors: Richards F. D. , Kalnins L. M. , Watts A. B. , Cohen B. E. , Beaman R. J. 
Published: September 2018

AbstractBasement structure is known to exert strong magmatic and morphological control on continental volcanoes, but relatively little is known about the structural control of submarine volcanoes. Here we investigate the morphology of the Tasmantid Seamounts, a >2,400 km long chain of age‐progressive intraplate volcanoes, ranging from 56 to 7 Ma. The seamounts are emplaced over the extinct Tasman Sea spreading center, which was active between 84 and 52 Ma. While thick sediment (∼1 km) obscures much of the basement, detailed morphological and geophysical analyses of the seamounts reveal a strong correlation between tectonic setting, seamount orientation, and volcanic structure, despite the ≥20 Ma interval between spreading cessation and seamount emplacement. Seamounts emplaced on fracture zones or spreading segment‐transform fault inside corners are typically large and elongate. Where original morphology is preserved, they often appear rugged and predominantly fissure‐fed. By contrast, comparatively smooth, conical seamounts with isolated dike‐fed flank cones are often found midsegment and at outside corners. Volcanic fabrics also align closely with the expected principal stress directions for strong mechanical coupling across transform faults. This behavior suggests the lithosphere is dissected by numerous deep faults, channeling magma along preexisting structural trends. Generally, low effective elastic thicknesses (<10 km) and lack of correlation with plate age at emplacement suggest that structural inheritance is also a major control on lithospheric strength near the extinct spreading center. Our study clearly demonstrates that, like in the continents, structural inheritance in oceanic lithosphere can exert significant control on the morphology of submarine volcanoes.
A Model for Crack Initiation in Solidifying Lava
Authors: Piombo Antonello , Dragoni Michele 
Published: September 2018

AbstractWe study the thermomechanical evolution of a stationary lava body cooling from the upper surface. The body progressively solidifies and develops a boundary layer made of an upper solid thermoelastic crust and a lower viscoelastic layer. The presented approach to the problem is one‐dimensional and quasi‐static. Under the assumption that the crust is a brittle solid with a given strength, we study the generation of tensile fractures. We consider a single fracture event and we assume that a fracture is produced when the thermal stress exceeds the strength over a certain depth interval, inferred from the observation of striae. The fracture propagates abruptly across the brittle layer, driven by the difference between the thermal stress and the tensile strength. The model can contribute to explain the formation of striae, surfaces caused by crack advance, in particular, of the first fracture. We find that the Young modulus controls the crack growth. The model provides an explanation for the presence of the rough bands on striae. For its higher values the fracture extends partially into the viscoelastic region; while for lower values the crack is confined to the brittle layer. The maximum opening width is typically in the order of a few thousandths of the vertical length of the crack. The resumption of crack process must await further cooling of the lava body.
Flexible Coupling in Joint Inversions: A Bayesian Structure Decoupling Algorithm
Authors: Piana Agostinetti Nicola , Bodin Thomas 
Published: September 2018

AbstractWhen different geophysical observables are sensitive to the same volume, it is possible to invert them simultaneously to jointly constrain different physical properties. The question addressed in this study is to determine which structures (e.g., interfaces) are common to different properties and which ones are separated. We present an algorithm for resolving the level of spatial coupling between physical properties and to enable both common and separate structures in the same model. The new approach, called structure decoupling (SD) algorithm, is based on a Bayesian trans‐dimensional adaptive parameterization, where models can display the full spectra of spatial coupling between physical properties, from fully coupled models, that is, where identical model geometries are imposed across all inverted properties, to completely decoupled models, where an independent parameterization is used for each property. We apply the algorithm to three 1‐D geophysical inverse problems, using both synthetic and field data. For the synthetic cases, we compare the SD algorithm to standard Markov chain Monte Carlo and reversible‐jump Markov chain Monte Carlo approaches that use either fully coupled or fully decoupled parameterizations. In case of coupled structures, the SD algorithm does not behave differently from methods that assume common interfaces. In case of decoupled structures, the SD approach is demonstrated to correctly retrieve the portion of profiles where the physical properties do not share the same structure. The application of the new algorithm to field data demonstrates its ability to decouple structures where a common stratification is not supported by the data.
Drivers of Antarctic Sea Ice Volume Change in CMIP5 Models
Authors: Schroeter S. , Hobbs W. , Bindoff N. L. , Massom R. , Matear R. 
Published: September 2018

AbstractAntarctic sea ice trends have to date been linked to surface winds, through sea ice motion and atmospheric thermal advection. This paper analyzes sea ice volume in 10 Coupled Model Intercomparison Project Phase 5 (CMIP5) model configurations under pre‐industrial and historical climate forcings, to compare the relative importance of ice motion and thermodynamic processes. We find that the models' responses to historical forcings is dependent on their sea ice motion formulation; models with low‐magnitude sea ice motion tend to have historical trends that are dominated by thermodynamic processes, while sea ice models with higher‐magnitude motion have more spatially variable relative contributions from dynamic and thermodynamic processes. Trends at the sea ice edge during the season of sea ice advance are generally dominated by dynamic processes, whereas during retreat thermodynamic trends dominate. The models show more disagreement in the sea ice interior. This analysis highlights the different estimates and patterns of sea ice volume among global climate models and offers insight into the drivers of sea ice volume change as well as the subsequent implications for simulated atmosphere‐sea ice‐ocean interactions.
LRH-1 mitigates intestinal inflammatory disease by maintaining epithelial homeostasis and cell survival
Authors: Bayrer James R. , Wang Hongtao , Nattiv Roy , Suzawa Miyuki , Escusa Hazel S. , Fletterick Robert J. , Klein Ophir D. , Moore David D. , Ingraham Holly A. 
Published: September 2018

AbstractEpithelial dysfunction and crypt destruction are defining features of inflammatory bowel disease (IBD). However, current IBD therapies targeting epithelial dysfunction are lacking. The nuclear receptor LRH-1 (NR5A2) is expressed in intestinal epithelium and thought to contribute to epithelial renewal. Here we show that LRH-1 maintains intestinal epithelial health and protects against inflammatory damage. Knocking out LRH-1 in murine intestinal organoids reduces Notch signaling, increases crypt cell death, distorts the cellular composition of the epithelium, and weakens the epithelial barrier. Human LRH-1 (hLRH-1) rescues epithelial integrity and when overexpressed, mitigates inflammatory damage in murine and human intestinal organoids, including those derived from IBD patients. Finally, hLRH-1 greatly reduces disease severity in T-cell-mediated murine colitis. Together with the failure of a ligand-incompetent hLRH-1 mutant to protect against TNFα-damage, these findings provide compelling evidence that hLRH-1 mediates epithelial homeostasis and is an attractive target for intestinal disease.
Two-site H2O2 photo-oxidation on haematite photoanodes
Authors: Avital Yotam Y. , Dotan Hen , Klotz Dino , Grave Daniel A. , Tsyganok Anton , Gupta Bhavana , Kolusheva Sofia , Visoly-Fisher Iris , Rothschild Avner , Yochelis Arik 
Published: September 2018

AbstractH2O2 is a sacrificial reductant that is often used as a hole scavenger to gain insight into photoanode properties. Here we show a distinct mechanism of H2O2 photo-oxidation on haematite (α-Fe2O3) photoanodes. We found that the photocurrent voltammograms display non-monotonous behaviour upon varying the H2O2 concentration, which is not in accord with a linear surface reaction mechanism that involves a single reaction site as in Eley–Rideal reactions. We postulate a nonlinear kinetic mechanism that involves concerted interaction between adions induced by H2O2 deprotonation in the alkaline solution with adjacent intermediate species of the water photo-oxidation reaction, thereby involving two reaction sites as in Langmuir–Hinshelwood reactions. The devised kinetic model reproduces our main observations and predicts coexistence of two surface reaction paths (bi-stability) in a certain range of potentials and H2O2 concentrations. This prediction is confirmed experimentally by observing a hysteresis loop in the photocurrent voltammogram measured in the predicted coexistence range.
Pathogenic variants in glutamyl-tRNAGln amidotransferase subunits cause a lethal mitochondrial cardiomyopathy disorder
Authors: Friederich Marisa W. , Timal Sharita , Powell Christopher A. , Dallabona Cristina , Kurolap Alina , Palacios-Zambrano Sara , Bratkovic Drago , Derks Terry G. J. , Bick David , Bouman Katelijne , Chatfield Kathryn C. , Damouny-Naoum Nadine , Dishop Megan K. , Falik-Zaccai Tzipora C. , Fares Fuad , Fedida Ayalla , Ferrero Ileana , Gallagher Renata C. , Garesse Rafael , Gilberti Micol , González Cristina , Gowan Katherine , Habib Clair , Halligan Rebecca K. , Kalfon Limor , Knight Kaz , Lefeber Dirk , Mamblona Laura , Mandel Hanna , Mory Adi , Ottoson John , Paperna Tamar , Pruijn Ger J. M. , Rebelo-Guiomar Pedro F. , Saada Ann , Sainz Bruno , Salvemini Hayley , Schoots Mirthe H. , Smeitink Jan A. , Szukszto Maciej J. , ter Horst Hendrik J. , van den Brandt Frans , van Spronsen Francjan J. , Veltman Joris A. , Wartchow Eric , Wintjes Liesbeth T. , Zohar Yaniv , Fernández-Moreno Miguel A. , Baris Hagit N. , Donnini Claudia , Minczuk Michal , Rodenburg Richard J. , Van Hove Johan L. K. 
Published: September 2018

AbstractMitochondrial protein synthesis requires charging mt-tRNAs with their cognate amino acids by mitochondrial aminoacyl-tRNA synthetases, with the exception of glutaminyl mt-tRNA (mt-tRNAGln). mt-tRNAGln is indirectly charged by a transamidation reaction involving the GatCAB aminoacyl-tRNA amidotransferase complex. Defects involving the mitochondrial protein synthesis machinery cause a broad spectrum of disorders, with often fatal outcome. Here, we describe nine patients from five families with genetic defects in a GatCAB complex subunit, including QRSL1, GATB, and GATC, each showing a lethal metabolic cardiomyopathy syndrome. Functional studies reveal combined respiratory chain enzyme deficiencies and mitochondrial dysfunction. Aminoacylation of mt-tRNAGln and mitochondrial protein translation are deficient in patients’ fibroblasts cultured in the absence of glutamine but restore in high glutamine. Lentiviral rescue experiments and modeling in S. cerevisiae homologs confirm pathogenicity. Our study completes a decade of investigations on mitochondrial aminoacylation disorders, starting with DARS2 and ending with the GatCAB complex.
An ultra-low thiourea catalyzed strain-release glycosylation and a multicatalytic diversification strategy
Authors: Xu Chunfa , Loh Charles C. J. 
Published: September 2018

AbstractThe utility of thiourea catalysis in selective glycosylation strategies has gained significant momentum lately due to its versatility in hydrogen bonding or anionic recognition activation modes. The use of these non-covalent interactions constitute a powerful means to construct glycosidic linkages as it mimics physiologically occurring glycosyltransferases. However, glycosyl donor activation through the currently employed catalysts is moderate such that, in general, catalyst loadings are rather high in these transformations. In addition, thiourea catalysis has not been well explored for the synthesis of furanosides. Herein, we demonstrate an ultra-low loadings stereoselective and stereospecific thiourea catalyzed strain-release furanosylation and pyranosylation strategy. Our ultra-low organocatalyzed furanosylation enables a multicatalytic strategy, which opens up a unique avenue towards rapid diversification of synthetic glycosides. In-situ NMR monitoring unravel insights into unknown reaction intermediates and initial rate kinetic studies reveal a plausible synergistic hydrogen bonding/Brønsted acid activation mode.
Reconfigurable MEMS Fano metasurfaces with multiple-input–output states for logic operations at terahertz frequencies
Authors: Manjappa Manukumara , Pitchappa Prakash , Singh Navab , Wang Nan , Zheludev Nikolay I. , Lee Chengkuo , Singh Ranjan 
Published: September 2018

AbstractA broad range of dynamic metasurfaces has been developed for manipulating the intensity, phase and wavefront of electromagnetic radiation from microwaves to optical frequencies. However, most of these metasurfaces operate in single-input–output state. Here, we experimentally demonstrate a reconfigurable MEMS Fano resonant metasurface possessing multiple-input–output (MIO) states that performs logic operations with two independently controlled electrical inputs and an optical readout at terahertz frequencies. The far-field behaviour of Fano resonance exhibits XOR and XNOR operations, while the near-field resonant confinement enables the NAND operation. The MIO configuration resembling hysteresis-type closed-loop behaviour is realized through inducing electromechanically tuneable out-of-plane anisotropy in the near-field coupling of constituent resonator structures. The XOR metamaterial gate possesses potential applications in cryptographically secured terahertz wireless communication networks. Furthermore, the MIO features could lay the foundation for the realization of programmable and randomly accessible metamaterials with enhanced electro-optical performance across terahertz, infrared and optical frequencies.
Polymerization driven monomer passage through monolayer chemical vapour deposition graphene
Authors: Zhang Tao , Liao Zhongquan , Sandonas Leonardo Medrano , Dianat Arezoo , Liu Xiaoling , Xiao Peng , Amin Ihsan , Gutierrez Rafael , Chen Tao , Zschech Ehrenfried , Cuniberti Gianaurelio , Jordan Rainer 
Published: September 2018

AbstractMass transport through graphene is receiving increasing attention due to the potential for molecular sieving. Experimental studies are mostly limited to the translocation of protons, ions, and water molecules, and results for larger molecules through graphene are rare. Here, we perform controlled radical polymerization with surface-anchored self-assembled initiator monolayer in a monomer solution with single-layer graphene separating the initiator from the monomer. We demonstrate that neutral monomers are able to pass through the graphene (via native defects) and increase the graphene defects ratio (Raman ID/IG) from ca. 0.09 to 0.22. The translocations of anionic and cationic monomers through graphene are significantly slower due to chemical interactions of monomers with the graphene defects. Interestingly, if micropatterned initiator-monolayers are used, the translocations of anionic monomers apparently cut the graphene sheet into congruent microscopic structures. The varied interactions between monomers and graphene defects are further investigated by quantum molecular dynamics simulations.
A rust fungal effector binds plant DNA and modulates transcription
Authors: Ahmed Md Bulbul , Santos Karen Cristine Gonçalves dos , Sanchez Ingrid Benerice , Petre Benjamin , Lorrain Cécile , Plourde Mélodie B. , Duplessis Sébastien , Desgagné-Penix Isabel , Germain Hugo 
Published: September 2018

AbstractThe basidiomycete Melampsora larici-populina causes poplar rust disease by invading leaf tissues and secreting effector proteins through specialized infection structures known as haustoria. The mechanisms by which rust effectors promote pathogen virulence are poorly understood. The present study characterized Mlp124478, a candidate effector of M. larici-populina. We used the models Arabidopsis thaliana and Nicotiana benthamiana to investigate the function of Mlp124478 in plant cells. We established that Mlp124478 accumulates in the nucleus and nucleolus, however its nucleolar accumulation is not required to promote growth of the oomycete pathogen Hyaloperonospora arabidopsidis. Stable constitutive expression of Mlp124478 in A. thaliana repressed the expression of genes involved in immune responses, and also altered leaf morphology by increasing the waviness of rosette leaves. Chip-PCR experiments showed that Mlp124478 associats'e with the TGA1a-binding DNA sequence. Our results suggest that Mlp124478 exerts a virulence activity and binds the TGA1a promoter to suppress genes induced in response to pathogen infection.
Bufonid herpesvirus 1 (BfHV1) associated dermatitis and mortality in free ranging common toads (Bufo bufo) in Switzerland
Authors: Origgi Francesco C. , Schmidt Benedikt R. , Lohmann Petra , Otten Patricia , Meier Roman K. , Pisano Simone R. R. , Moore-Jones Gaia , Tecilla Marco , Sattler Ursula , Wahli Thomas , Gaschen Veronique , Stoffel Michael H. 
Published: September 2018

AbstractHere we report the discovery and partial characterization of a novel herpesvirus tentatively named Bufonid herpesvirus 1 (BfHV1) from severe dermatitis in free ranging common toads (Bufo bufo) in Switzerland. The disease has been observed in toads every year since 2014, in spring, during the mating season, at different and distant locations. The virus is found in the skin and occasionally in the brain of infected toads. The genome of the virus is at least 158 Kb long and contains at least 152 open reading frames with a minimal length of 270 nt. The genome of BfHV1 contains all the signature genes that are present in alloherpesviruses. Phylogenetic analysis based on the amino acid sequence of the DNA polymerase and terminase proteins positions the novel virus among the members of the genus Batrachovirus, family Alloherpesviridae. This is the first herpesvirus ever characterized in common toads.
The use of natural media amendments to produce kale enhanced with functional lipids in controlled environment production system
Authors: Vidal Natalia P. , Pham Huong T. , Manful Charles , Pumphrey Ryley , Nadeem Muhammad , Cheema Mumtaz , Galagedara Lakshman , Leke-Aladekoba Adedayo , Abbey Lord , Thomas Raymond 
Published: September 2018

AbstractDiets high in vegetable consumption is highly correlated with reduced risk of developing common lifestyle related diseases. We investigated the effects of three natural growth media amendments [potassium humate, dry vermicast, volcanic minerals or Promix alone (Control)] in enhancing the accumulation of functional lipids in greenhouse grown kale. Functional lipids (n9, n6, n3 fatty acids, diglycerides, galactolipids and phytosterols) were assessed using either gas chromatography/mass spectrometry (GC/MS) or ultra-high performance liquid chromatography-high resolution tandem mass spectrometry (UHPLC-HRMS/MS). The results showed volcanic minerals and dry vermicast were the most successful in enhancing the accumulation of functional lipids in kale. For example, dry vermicast enhanced the accumulation of total C18:1n9 and C16:3n3 fatty acids, while total C18:2n6 fatty acid accumulation was enhanced by volcanic minerals. In conclusion, natural growing medium amendments are remarkably effective in modulating the accumulation of functional lipids in kale grown under controlled-environment conditions. This could be a useful strategy for functional foods production in control environment production systems. Increase access to kale with enhanced functional lipids could aid in increase consumption of these health promotive compounds in the diet with potential implications in population health.
Maternal high-fat diet consumption induces sex-dependent alterations of the endocannabinoid system and redox homeostasis in liver of adult rat offspring
Authors: Miranda Rosiane Aparecida , De Almeida Mariana Macedo , Rocha Camilla Pereira Dias Da , de Brito Fassarella Larissa , De Souza Luana Lopes , Souza Aline Fonseca Pereira De , Andrade Cherley Borba Vieira De , Fortunato Rodrigo Soares , Pazos-Moura Carmen Cabanelas , Trevenzoli Isis Hara 
Published: September 2018

AbstractMaternal diet plays a critical role in health development. Perinatal overnutrition induces metabolic dysfunctions and obesity in the offspring. Obesity is associated with endocannabinoid system (ECS) over activation and oxidative stress. Liver ECS activation induces hepatic steatosis, inflammation and fibrosis while the antagonism of cannabinoid receptors ameliorates these alterations. Here, we investigated the effect of perinatal maternal high-fat diet (HF, 29% of calories as fat) on the ECS and antioxidant system in liver of male and female adult rat offspring (180 days old). Maternal HF diet increased hepatic cannabinoid receptors, ECS metabolizing enzymes and triglyceride content, with male offspring more affected. ECS changes are likely independent of estradiol serum levels but associated with increased hepatic content of estrogen receptor, which can stimulate the expression of ECS components. Differently, maternal HF diet decreased the activity of the antioxidant enzymes glutathione peroxidase, superoxide dismutase and catalase, and increased oxidative stress markers in both sexes. Alterations in the redox homeostasis were associated with mitochondria damage but not with liver fibrosis. Our data suggest that maternal HF diet induces ECS over activation in adulthood, and that male offspring are at higher risk to develop liver disease compared with female rats.