bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seasonal Changes in Hydrogen Escape From Mars Through Analysis of HST Observations of the Martian Exosphere Near Perihelion
Authors: Bhattacharyya D. , Clarke J. T. , Chaufray J. Y. , Mayyasi M. , Bertaux J. L. , Chaffin M. S. , Schneider N. M. , Villanueva G. L. 
Published: November 2017

AbstractHubble Space Telescope (HST) observations of the Martian hydrogen exosphere in Lyman α are presented in this paper for a period when Mars passed perihelion and southern summer solstice in its orbit. The peak intensity in the exospheric Lyman α brightness was recorded after Mars went past its perihelion, slightly after southern summer solstice. The increase in brightness as Mars approached perihelion was found to not be symmetric around the peak, making it impossible to fit the H escape flux trend with a single sinusoidal curve with the peak at perihelion. While the short‐term (~30 Earth days) changes were not directly correlated with changes in the solar Lyman α flux, the long‐term (~10 Earth years) trend in the data does show some correlation with solar activity. This suggests that the short‐term changes brought about in the exosphere could be due to intrinsic changes occurring within the lower atmosphere. For example, thermospheric heating by dust can alter the cold‐trapping mechanism for water vapor resulting in it being present in large quantities at higher altitudes (60–80 km), possibly enhancing the escape flux of H. Therefore, it is important to understand the drivers of atmospheric dynamics in the Martian atmosphere, which produce the yearly enhanced seasonal changes observed at Mars around periapsis and southern summer solstice in order to accurately determine the total amount of water lost over its history.
On the Origin of Ionospheric Hiss: A Conjugate Observation
Authors: Zhima Zeren , Chen Lunjin , Xiong Ying , Cao Jinbin , Fu Huishan 
Published: November 2017

AbstractWe present a conjugate observation on whistler mode electromagnetic hiss from the low Earth orbit satellite Detection of Electro‐Magnetic Emissions Transmitted from Earthquake Regions (DEMETER) and the high‐altitude elliptical orbit spacecraft Time History of Events and Macroscale Interactions during Substorms (THEMIS). The conjugate observation was performed at 14:51:10 to 15:12:00 UT on 15 June 2010, when DEMETER was flying across the L shell region from ~1.39 to 2.80 at an altitude of ~660 km; meanwhile, THEMIS probes were passing through the L shell region from ~1.64 to 1.91 at altitudes from ~1.6 to 2.0 RE. The conjugated observations demonstrate similar time‐frequency structures between the ionospheric hiss (~350 to 800 Hz) captured by DEMETER and the plasmaspheric hiss (~350 to 900 Hz) recorded by THEMIS probes, including similar peak frequencies (~500 to 600 Hz), similar lower cutoff frequencies (~350 to 400 Hz), and upper cutoff frequencies (~730 to 800 Hz). The wave vector analyses show that the ionospheric hiss propagates obliquely downward to the Earth and slightly equatorward with right‐handed polarization, suggesting that its source comes from higher altitudes. Ray tracing simulations with the constraint of observations verify that the connection between ionospheric and plasmaspheric hiss is physically possible through wave propagation. This study provides direct observational evidence to support the mechanism that high‐altitude plasmaspheric hiss is responsible for the generation of low‐altitude ionospheric hiss.
Resolving the Origin of Pseudo‐Single Domain Magnetic Behavior
Authors: Roberts Andrew P. , Almeida Trevor P. , Church Nathan S. , Harrison Richard J. , Heslop David , Li Yiliang , Li Jinhua , Muxworthy Adrian R. , Williams Wyn , Zhao Xiang 
Published: November 2017

AbstractThe term “pseudo‐single domain” (PSD) has been used to describe the transitional state in rock magnetism that spans the particle size range between the single domain (SD) and multidomain (MD) states. The particle size range for the stable SD state in the most commonly occurring terrestrial magnetic mineral, magnetite, is so narrow (~20–75 nm) that it is widely considered that much of the paleomagnetic record of interest is carried by PSD rather than stable SD particles. The PSD concept has, thus, become the dominant explanation for the magnetization associated with a major fraction of particles that record paleomagnetic signals throughout geological time. In this paper, we argue that in contrast to the SD and MD states, the term PSD does not describe the relevant physical processes, which have been documented extensively using three‐dimensional micromagnetic modeling and by parallel research in material science and solid‐state physics. We also argue that features attributed to PSD behavior can be explained by nucleation of a single magnetic vortex immediately above the maximum stable SD transition size. With increasing particle size, multiple vortices, antivortices, and domain walls can nucleate, which produce variable cancellation of magnetic moments and a gradual transition into the MD state. Thus, while the term PSD describes a well‐known transitional state, it fails to describe adequately the physics of the relevant processes. We recommend that use of this term should be discontinued in favor of “vortex state,” which spans a range of behaviors associated with magnetic vortices.
Analysis of the Diurnal Variation of the Global Electric Circuit Obtained From Different Numerical Models
Authors: Jánský Jaroslav , Lucas Greg M. , Kalb Christina , Bayona Victor , Peterson Michael J. , Deierling Wiebke , Flyer Natasha , Pasko Victor P. 
Published: November 2017

AbstractThis work analyzes different current source and conductivity parameterizations and their influence on the diurnal variation of the global electric circuit (GEC). The diurnal variations of the current source parameterizations obtained using electric field and conductivity measurements from plane overflights combined with global Tropical Rainfall Measuring Mission satellite data give generally good agreement with measured diurnal variation of the electric field at Vostok, Antarctica, where reference experimental measurements are performed. An approach employing 85 GHz passive microwave observations to infer currents within the GEC is compared and shows the best agreement in amplitude and phase with experimental measurements. To study the conductivity influence, GEC models solving the continuity equation in 3‐D are used to calculate atmospheric resistance using yearly averaged conductivity obtained from the global circulation model Community Earth System Model (CESM). Then, using current source parameterization combining mean currents and global counts of electrified clouds, if the exponential conductivity is substituted by the conductivity from CESM, the peak to peak diurnal variation of the ionospheric potential of the GEC decreases from 24% to 20%. The main reason for the change is the presence of clouds while effects of 222Rn ionization, aerosols, and topography are less pronounced. The simulated peak to peak diurnal variation of the electric field at Vostok is increased from 15% to 18% from the diurnal variation of the global current in the GEC if conductivity from CESM is used.
The Impact of Nonequilibrium and Equilibrium Fractionation on Two Different Deuterium Excess Definitions
Authors: Dütsch Marina , Pfahl Stephan , Sodemann Harald 
Published: November 2017

AbstractThe deuterium excess (d) is a useful measure for nonequilibrium effects of isotopic fractionation and can therefore provide information about the meteorological conditions in evaporation regions or during ice cloud formation. In addition to nonequilibrium fractionation, two other effects can change d during phase transitions. The first is the dependence of the equilibrium fractionation factors on temperature, and the second is the nonlinearity of the δ scale on which d is defined. The second effect can be avoided by using an alternative definition that is based on the logarithmic scale. However, in this case d is not conserved when air parcels mix, which can lead to changes without phase transitions. Here we provide a systematic analysis of the benefits and limitations of both deuterium excess definitions by separately quantifying the impact of the nonequilibrium effect, the temperature effect, the δ‐scale effect, and the mixing effect in a simple Rayleigh model simulating the isotopic composition of air parcels during moist adiabatic ascent. The δ‐scale effect is important in depleted air parcels, for which it can change the sign of the traditional deuterium excess in the remaining vapor from negative to positive. The alternative definition mainly reflects the nonequilibrium and temperature effect, while the mixing effect is about 2 orders of magnitude smaller. Thus, the alternative deuterium excess definition appears to be a more accurate measure for nonequilibrium effects in situations where moisture is depleted and the δ‐scale effect is large, for instance, at high latitudes or altitudes.
Estimating Global Ecosystem Isohydry/Anisohydry Using Active and Passive Microwave Satellite Data
Authors: Li Yan , Guan Kaiyu , Gentine Pierre , Konings Alexandra G. , Meinzer Frederick C. , Kimball John S. , Xu Xiangtao , Anderegg William R. L. , McDowell Nate G. , Martinez‐Vilalta Jordi , Long David G. , Good Stephen P. 
Published: November 2017

AbstractThe concept of isohydry/anisohydry describes the degree to which plants regulate their water status, operating from isohydric with strict regulation to anisohydric with less regulation. Though some species level measures of isohydry/anisohydry exist at a few locations, ecosystem‐scale information is still largely unavailable. In this study, we use diurnal observations from active (Ku‐Band backscatter from QuikSCAT) and passive (X‐band vegetation optical depth (VOD) from Advanced Microwave Scanning Radiometer on EOS Aqua) microwave satellite data to estimate global ecosystem isohydry/anisohydry. Here diurnal observations from both satellites approximate predawn and midday plant canopy water contents, which are used to estimate isohydry/anisohydry. The two independent estimates from radar backscatter and VOD show reasonable agreement at low and middle latitudes but diverge at high latitudes. Grasslands, croplands, wetlands, and open shrublands are more anisohydric, whereas evergreen broadleaf and deciduous broadleaf forests are more isohydric. The direct validation with upscaled in situ species isohydry/anisohydry estimates indicates that the VOD‐based estimates have much better agreement than the backscatter‐based estimates. The indirect validation with prior knowledge suggests that both estimates are generally consistent in that vegetation water status of anisohydric ecosystems more closely tracks environmental fluctuations of water availability and demand than their isohydric counterparts. However, uncertainties still exist in the isohydry/anisohydry estimate, primarily arising from the remote sensing data and, to a lesser extent, from the methodology. The comprehensive assessment in this study can help us better understand the robustness, limitation, and uncertainties of the satellite‐derived isohydry/anisohydry estimates. The ecosystem isohydry/anisohydry has the potential to reveal new insights into spatiotemporal ecosystem response to droughts.
Partially Ordered Sets
Authors: Fattore Marco 
Published: November 2017

AbstractA partially ordered set is a set endowed with an ordering criterion, which is in general not complete, that is, such that some pairs of elements of the set cannot be ordered or compared. Partially ordered sets are the natural setting for the description and the analysis of multidimensional systems of indicators, particularly, but not exclusively, when they are of an ordinal kind. They can be used in evaluation studies, for the computation of non‐aggregative synthetic indicators, for the definition of rankings, in cluster analysis, and in many other data analysis tasks. As the availability of complex ordinal data sets and multidimensional indicator systems is increasing, partially ordered sets are becoming a key tool for applied statistics, particularly in socio‐economics, environmental and ecological studies, and multicriteria decision‐making. Their use may involve heavy computations, but effective algorithms and software resources exist that make them a very useful tool in many concrete problems.
The Control of Flowering: Do Genetical and Physiological Approaches Converge?
Authors: Périlleux Claire , Bernier Georges 
Published: November 2017

AbstractThe sections in this article areIntroductionFloral Meristem Identity GenesFloral Repression Genes and PathwayFloral Promotion Genes and PathwaysInteractions between Different Genes and Pathways: Welcome to ComplexityConclusionsAcknowledgements
The Central Role of the Ovule in Apomixis and Parthenocarpy
Authors: Koltunow Anna M. , Vivian‐Smith Adam , Tucker Matthew R. , Paech Nicholas 
Published: November 2017

AbstractThe sections in this article areIntroductionDevelopment of Floral, Seed and Fruit StructuresEvolutionary Origin of Ovules, Seeds and FruitsPlant Hormones Facilitate Long‐Range Communication within and between Floral Organs during Fruit and Seed InitiationApomixis—A Seed by Any Means?Parthenocarpic Fruit Development and the Analysis of Fruit InitiationConclusions
Signaling by Protein Phosphorylation in Cell Division
Authors: Sasabe Michiko , Machida Yasunori 
Published: November 2017

AbstractRegulation of cell division in eukaryotes including higher plants is crucial for growth, differentiation, development, and cell death. Protein phosphorylation plays a major role in signaling to control the cell division, and is driven by protein kinases called mitotic kinases, including a cyclin‐dependent kinase (CDK), an Aurora kinase, and a mitogen‐activated protein kinase (MAPK). In contrast to animals and yeast, our knowledge on the regulatory mechanism of the cell division in plants is very limited. Although plant cells seem to share some basic processes during the cell cycle progression with animal and yeast cells, they have acquired unique molecules orchestrating the cell division, reflecting the plant‐specific fashion in cell division such as cytokinesis. This chapter focuses on recent advances in the understanding of signaling molecules, so‐called mitotic kinases (CDKs, Auroras, MAPKs) during mitosis and cytokinesis in plant cells.
Induced Resistance – Orchestrating Defence Mechanisms through Crosstalk and Priming
Authors: van der Ent Sjoerd , Koornneef Annemart , Ton Jurriaan , Pieterse Corné M.J. 
Published: November 2017

AbstractIn nature, plants interact with a wide range of microbial pathogens and herbivorous insects. During the evolutionary arms race between plants and their attackers, primary and secondary immune responses evolved to recognise common or highly specialised features of the attacker encountered, resulting in sophisticated mechanisms of induced defence. Induced resistance mechanisms are characterised by a broad‐spectrum effectiveness and often act systemically in plant parts distant from the site of primary attack, thereby protecting the plant against subsequent invaders. Plant hormones are key players in the regulation of the defence signalling pathways involved. Because induced defence responses entail ecological fitness costs, plants must possess elaborate regulatory mechanisms that efficiently coordinate the activation of attacker‐specific defences so that fitness costs are minimised while optimal resistance is attained. A major focus in plant defence signalling research is to uncover key mechanisms by which plants tailor their responses to different attackers, and to investigate how plants cope with simultaneous interactions with multiple aggressors. Pathway crosstalk and priming for enhanced defence emerged as important regulatory mechanisms that enhance the efficiency of the plant's inducible defence arsenal. Here, we review the current knowledge on the signalling cascades involved in different types of induced pathogen and insect resistance, and the regulatory mechanisms by which plants are able to orchestrate their inducible defences in a cost‐effective manner.
Clarion call for histopathological clot analysis in “cryptogenic” ischemic stroke: implications for diagnosis and treatment
Authors: Bhaskar Sonu , Cordato Dennis , Cappelen‐Smith Cecilia , Cheung Andrew , Ledingham David , Celermajer David , Levi Christopher 
Published: November 2017

AbstractDiagnosis, treatment, and secondary management of cryptogenic stroke patients pose a formidable challenge. The scenario is further complicated in patients with native and prosthetic valvular heart disease. We present a case study of a 36‐year‐old man who received intravenous thrombolysis (IV‐tPA) and endovascular thrombectomy (EVT) for presumed “cryptogenic” complete middle cerebral artery infarction who made a surprisingly excellent clinical recovery despite poor baseline and postintervention neuroimaging. Retrospective gram stain of his clot confirmed a diagnosis of infective endocarditis. This raises an important issue regarding need for more routine histopathological analysis of clot retrieved after EVT in “cryptogenic” stroke patients particularly those with valvular heart disease.
Electromagnetic Shielding Hybrid Nanogenerator for Health Monitoring and Protection
Authors: Zhang Qian , Liang Qijie , Zhang Zheng , Kang Zhuo , Liao Qingliang , Ding Yi , Ma Mingyuan , Gao Fangfang , Zhao Xuan , Zhang Yue 
Published: November 2017

AbstractNowadays, mankind faces increasingly energy crisis and electromagnetic radiation pollution. An energy harvester with function of protecting human health from electromagnetic radiation is a desirable solution to this problem. Here, a stretchable electromagnetic shielding hybrid nanogenerator (ES‐HNG) is reported which can not only scavenge thermal and mechanical energy from living environment but also protect and monitor human health. The ES‐HNG is capable of transforming mechanical and thermal energy to electricity based on triboelectric, piezoelectric, and pyroelectric effects. To be devised as a computer keyboard cover, ES‐HNG takes about 200 s to charge a capacitor to 3 V by typing. The stored energy can drive the portable devices successfully. Besides, the ES‐HNG eliminates electromagnetic radiation of computer completely due to its unique electromagnetic shielding property. A large range of electromagnetic wave (frequency is between 0 and 1.5 GHz) is shielded more than 99.9978% by the ES‐HNG. Moreover, the ES‐HNG is able to monitor human health by attaching it on human abdomen to be a self‐powered sensor. This work opens up a new prospect of harvesting energy effectively as well as protecting/monitoring human health from electromagnetic radiation surroundings.
Flexible Graphene Solution‐Gated Field‐Effect Transistors: Efficient Transducers for Micro‐Electrocorticography
Authors: Hébert Clement , Masvidal‐Codina Eduard , Suarez‐Perez Alejandro , Calia Andrea Bonaccini , Piret Gaelle , Garcia‐Cortadella Ramon , Illa Xavi , Del Corro Garcia Elena , De la Cruz Sanchez Jose M. , Casals Damia Viana , Prats‐Alfonso Elisabet , Bousquet Jessica , Godignon Philippe , Yvert Blaise , Villa Rosa , Sanchez‐Vives Maria V. , Guimerà‐Brunet Anton , Garrido Jose A. 
Published: November 2017

AbstractBrain–computer interfaces and neural prostheses based on the detection of electrocorticography (ECoG) signals are rapidly growing fields of research. Several technologies are currently competing to be the first to reach the market; however, none of them fulfill yet all the requirements of the ideal interface with neurons. Thanks to its biocompatibility, low dimensionality, mechanical flexibility, and electronic properties, graphene is one of the most promising material candidates for neural interfacing. After discussing the operation of graphene solution‐gated field‐effect transistors (SGFET) and characterizing their performance in saline solution, it is reported here that this technology is suitable for μ‐ECoG recordings through studies of spontaneous slow‐wave activity, sensory‐evoked responses on the visual and auditory cortices, and synchronous activity in a rat model of epilepsy. An in‐depth comparison of the signal‐to‐noise ratio of graphene SGFETs with that of platinum black electrodes confirms that graphene SGFET technology is approaching the performance of state‐of‐the art neural technologies.
The Salt Matters: Enhanced Reversibility of Li–O2 Batteries with a Li[(CF3SO2)(n‐C4F9SO2)N]‐Based Electrolyte
Authors: Tong Bo , Huang Jun , Zhou Zhibin , Peng Zhangquan 
Published: November 2017

AbstractThe safety hazards and cycle instability of lithium metal anodes (LMA) constitute significant barriers to progress in lithium metal batteries. This situation is worse in Li–O2 batteries because the LMA is prone to be chemically attacked by O2 shuttled from the cathode. Notwithstanding, efforts on LMA are much sparse than those on the cathode in the realm of Li–O2 batteries. Here, a novel lithium salt of Li[(CF3SO2)(n‐C4F9SO2)N] (LiTNFSI) is reported, which can effectively suppress the parasitic side reactions and dendrite growth of LMA during cycling and thereby significantly enhance the overall reversibility of Li–O2 batteries. A variety of advanced research tools are employed to scrutinize the working principles of the LiTNFSI salt. It is revealed that a stable, uniform, and O2‐resistive solid electrolyte interphase is formed on LMA, and hence the “cross‐talk” between the LMA and O2 shuttled from the cathode is remarkably inhibited in LiTNFSI‐based Li–O2 batteries.
Superior Toughness and Fast Self‐Healing at Room Temperature Engineered by Transparent Elastomers
Authors: Kim Seon‐Mi , Jeon Hyeonyeol , Shin Sung‐Ho , Park Seul‐A , Jegal Jonggeon , Hwang Sung Yeon , Oh Dongyeop X. , Park Jeyoung 
Published: November 2017

AbstractThe most important properties of self‐healing polymers are efficient recovery at room temperature and prolonged durability. However, these two characteristics are contradictory, making it difficult to optimize them simultaneously. Herein, a transparent and easily processable thermoplastic polyurethane (TPU) with the highest reported tensile strength and toughness (6.8 MPa and 26.9 MJ m−3, respectively) is prepared. This TPU is superior to reported contemporary room‐temperature self‐healable materials and conveniently heals within 2 h through facile aromatic disulfide metathesis engineered by hard segment embedded aromatic disulfides. After the TPU film is cut in half and respliced, the mechanical properties recover to more than 75% of those of the virgin sample within 2 h. Hard segments with an asymmetric alicyclic structure are more effective than those with symmetric alicyclic, linear aliphatic, and aromatic structures. An asymmetric structure provides the optimal metathesis efficiency for the embedded aromatic disulfide while preserving the remarkable mechanical properties of TPU, as indicated by rheological and surface investigations. The demonstration of a scratch‐detecting electrical sensor coated on a tough TPU film capable of auto‐repair at room temperature suggests that this film has potential applications in the wearable electronics industry.