bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pyroconvection Risk in Australia: Climatological Changes in Atmospheric Stability and Surface Fire Weather Conditions
Authors: Dowdy Andrew J. , Pepler Acacia 
Published: January 2018

AbstractExtreme wildfires with strong convective processes in their plumes have recently led to disastrous impacts on various regions of the world. The Continuous Haines index (CH) is used in Australia to represent vertical atmospheric stability and humidity measures relating to pyroconvective processes. CH climatology is examined here using reanalysis data from 1979 to 2016, revealing large spatial and seasonal variations throughout Australia. Various measures of severity are investigated, including regionally specific thresholds. CH is combined with near‐surface fire weather conditions, as a type of compound event, and is examined in relation to environmental conditions associated with pyroconvection. Significant long‐term changes in CH are found for some regions and seasons, with these changes corresponding to changes in near‐surface conditions in some cases. In particular, an increased risk of pyroconvection is identified for southeast Australia during spring and summer, due to decreased vertical atmospheric stability and humidity combined with more severe near‐surface conditions.
Questioning the Influence of Sunspots on Amazon Hydrology: Even a Broken Clock Tells the Right Time Twice a Day
Authors: Baker J. C. A. , Gloor M. , Boom A. , Neill D. A. , Cintra B. B. L. , Clerici S. J. , Brienen R. J. W. 
Published: January 2018

AbstractIt was suggested in a recent article that sunspots drive decadal variation in Amazon River flow. This conclusion was based on a novel time series decomposition method used to extract a decadal signal from the Amazon River record. We have extended this analysis back in time, using a new hydrological proxy record of tree ring oxygen isotopes (δ18OTR). Consistent with the findings of Antico and Torres, we find a positive correlation between sunspots and the decadal δ18OTR cycle from 1903 to 2012 (r = 0.60, p < 0.001). However, the relationship does not persist into the preceding century and even becomes weakly negative (r = −0.30, p = 0.11, 1799–1902). This result casts considerable doubt over the mechanism by which sunspots are purported to influence Amazon hydrology.
The Sidebands of the Equatorial Electrojet: General Characteristic of the Westward Currents, as Deduced From CHAMP
Authors: Zhou Yun‐Liang , Lühr Hermann , Alken Patrick 
Published: January 2018

AbstractBased on 5 years (2001–2005) of magnetic field measurements made by the CHAMP satellite, latitudinal profiles of the equatorial electrojet (EEJ) have been derived. This study provides a comprehensive characterization of the reverse current EEJ sidebands. These westward currents peak at ±5° quasi‐dipole latitude with typical amplitudes of 35% of the main EEJ. The diurnal amplitude variation is quite comparable with that of the EEJ. Similarly to the EEJ, the intensity is increasing with solar EUV flux, but with a steeper slope, indicating that not only the conductivity plays a role. For the longitude distribution we find, in general, larger amplitudes in the Western than in the Eastern Hemisphere. It is presently a common understanding that the reverse current EEJ sidebands are generated by eastward zonal winds at altitudes above about 120 km. In particular, a positive vertical gradient of wind speed generates westward currents at magnetic latitudes outside of 2° dip latitude. Interesting information about these features can be deduced from the sidebands' tidal characteristics. The longitudinal variation of the amplitude is dominated by a wave‐1 pattern, which can primarily be attributed to the tidal components SPW1 and SW3. In case of the hemispheric amplitude differences these same two wave‐1 components dominate. The ratio between sideband amplitude and main EEJ is largely controlled by the tidal features of the EEJ. The longitudinal patterns of the latitude, where the sidebands peak, resemble to some extent those of the amplitude. Current densities become larger when the peaks move closer to the magnetic equator.
Lunar Tidal Modulation of Periodic Meridional Movement of Equatorial Ionization Anomaly Crest During Sudden Stratospheric Warming
Authors: Mo X. H. , Zhang D. H. 
Published: January 2018

AbstractUsing the location of equatorial ionization anomaly (EIA) crest derived from GPS observations in China and Brazilian sector, we investigated the longitudinal dependence of periodic meridional movement of EIA crest during sudden stratospheric warming events in 2003, 2006, and 2009. The solar activity was from high to low for the three events. Results show that the locations of EIA crests in both China and Brazilian sectors exhibit obvious and constant 14‐ to 15‐day periodic oscillation being in‐phase in two sectors, which coincide with the half of the lunar revolution period (29.53 days) and the lunar phase. The temporal extent of wave power at 14–15 days is consistent with the temporal extent of stratospheric zonal wind, indicating that 14‐ to 15‐day periodic meridional movement of EIA crest is due to enhanced lunar tide modulated by zonal wind. In addition, it is also found that the amplitude of 14‐ to 15‐day periodic oscillation of EIA crest in China sector is larger than that in Brazilian sector, which may be caused by the longitudinal variation of tides and neutral wind pattern.
A Full‐Stokes 3‐D Calving Model Applied to a Large Greenlandic Glacier
Authors: Todd Joe , Christoffersen Poul , Zwinger Thomas , Råback Peter , Chauché Nolwenn , Benn Doug , Luckman Adrian , Ryan Johnny , Toberg Nick , Slater Donald , Hubbard Alun 
Published: January 2018

AbstractIceberg calving accounts for around half of all mass loss from both the Greenland and Antarctic ice sheets. The diverse nature of calving and its complex links to both internal dynamics and climate make it challenging to incorporate into models of glaciers and ice sheets. Here we present results from a new open‐source 3‐D full‐Stokes calving model developed in Elmer/Ice. The calving model implements the crevasse depth criterion, which states that calving occurs when surface and basal crevasses penetrate the full thickness of the glacier. The model also implements a new 3‐D rediscretization approach and a time‐evolution scheme which allow the calving front to evolve realistically through time. We test the model in an application to Store Glacier, one of the largest outlet glaciers in West Greenland, and find that it realistically simulates the seasonal advance and retreat when two principal environmental forcings are applied. These forcings are (1) submarine melting in distributed and concentrated forms and (2) ice mélange buttressing. We find that ice mélange buttressing is primarily responsible for Store Glacier's seasonal advance and retreat. Distributed submarine melting prevents the glacier from forming a permanent floating tongue, while concentrated plume melting has a disproportionately large and potentially destabilizing effect on the calving front position. Our results also highlight the importance of basal topography, which exerts a strong control on calving, explaining why Store Glacier has remained stable during a period when neighboring glaciers have undergone prolonged interannual retreat.
Transpiration Dominates Ecosystem Water‐Use Efficiency in Response to Warming in an Alpine Meadow
Authors: Quan Quan , Zhang Fangyue , Tian Dashuan , Zhou Qingping , Wang Lixin , Niu Shuli 
Published: January 2018

AbstractAs a key linkage of C and water cycles, water‐use efficiency (WUE) quantifies how much water an ecosystem uses for carbon gain. Although ecosystem C and water fluxes have been intensively studied, yet it remains unclear how ecosystem WUE responds to climate warming and which processes dominate the response of WUE. To answer these questions, we examined canopy WUE (WUEc), ecosystem WUE (WUEe) and their components including gross ecosystem productivity, ecosystem evapotranspiration (ET), soil evaporation (E), and plant canopy transpiration (T), in response to warming in an alpine meadow by using a manipulative warming experiment in 2015 and 2016. As expected, low‐ and high‐level warming treatments increased soil temperature (Tsoil) at 10 cm on average by 1.65 and 2.77°C, but decreased soil moisture (Msoil) by 2.52 and 7.6 vol %, respectively, across the two years. Low‐ and high‐level warming increased WUEe by 7.7 and 9.3% over the two years, but rarely changed WUEc in either year. T/ET ratio determined the differential responses of WUEc and WUEe. Larger T/ET led to less difference between WUEc and WUEe. By partitioning WUEc and WUEe into different carbon and water fluxes, we found that T rather than gross ecosystem productivity or E dominated the responses of WUEc and WUEe to warming. This study provides empirical insights into how ecosystem WUE responds to warming and illustrates the importance of plant transpiration in regulating ecosystem WUE under future climate change.
Modeling Subsurface Hydrology in Floodplains
Authors: Evans Cristina M. , Dritschel David G. , Singer Michael B. 
Published: January 2018

AbstractSoil‐moisture patterns in floodplains are highly dynamic, owing to the complex relationships between soil properties, climatic conditions at the surface, and the position of the water table. Given this complexity, along with climate change scenarios in many regions, there is a need for a model to investigate the implications of different conditions on water availability to riparian vegetation. We present a model, HaughFlow, which is able to predict coupled water movement in the vadose and phreatic zones of hydraulically connected floodplains. Model output was calibrated and evaluated at six sites in Australia to identify key patterns in subsurface hydrology. This study identifies the importance of the capillary fringe in vadose zone hydrology due to its water storage capacity and creation of conductive pathways. Following peaks in water table elevation, water can be stored in the capillary fringe for up to months (depending on the soil properties). This water can provide a critical resource for vegetation that is unable to access the water table. When water table peaks coincide with heavy rainfall events, the capillary fringe can support saturation of the entire soil profile. HaughFlow is used to investigate the water availability to riparian vegetation, producing daily output of water content in the soil over decadal time periods within different depth ranges. These outputs can be summarized to support scientific investigations of plant‐water relations, as well as in management applications.
Prerequisites for Accurate Monitoring of River Discharge Based on Fixed‐Location Velocity Measurements
Authors: Kästner K. , Hoitink A. J. F. , Torfs P. J. J. F. , Vermeulen B. , Ningsih N. S. , Pramulya M. 
Published: January 2018

AbstractRiver discharge has to be monitored reliably for effective water management. As river discharge cannot be measured directly, it is usually inferred from the water level. This practice is unreliable at places where the relation between water level and flow velocity is ambiguous. In such a case, the continuous measurement of the flow velocity can improve the discharge prediction. The emergence of horizontal acoustic Doppler current profilers (HADCPs) has made it possible to continuously measure the flow velocity. However, the profiling range of HADCPs is limited, so that a single instrument can only partially cover a wide cross section. The total discharge still has to be determined with a model. While the limitations of rating curves are well understood, there is not yet a comprehensive theory to assess the accuracy of discharge predicted from velocity measurements. Such a theory is necessary to discriminate which factors influence the measurements, and to improve instrument deployment as well as discharge prediction. This paper presents a generic method to assess the uncertainty of discharge predicted from range‐limited velocity profiles. The theory shows that a major source of error is the variation of the ratio between the local and cross‐section‐averaged velocity. This variation is large near the banks, where HADCPs are usually deployed and can limit the advantage gained from the velocity measurement. We apply our theory at two gauging stations situated in the Kapuas River, Indonesia. We find that at one of the two stations the index velocity does not outperform a simple rating curve.
Limitless Analytic Elements
Authors: Strack O. D. L. 
Published: January 2018

AbstractWe present equations for new limitless analytic line elements. These elements possess a virtually unlimited number of degrees of freedom. We apply these new limitless analytic elements to head‐specified boundaries and to problems with inhomogeneities in hydraulic conductivity. Applications of these new analytic elements to practical problems involving head‐specified boundaries require the solution of a very large number of equations. To make the new elements useful in practice, an efficient iterative scheme is required. We present an improved version of the scheme presented by Bandilla et al. (2007), based on the application of Cauchy integrals. The limitless analytic elements are useful when modeling strings of elements, rivers for example, where local conditions are difficult to model, e.g., when a well is close to a river. The solution of such problems is facilitated by increasing the order of the elements to obtain a good solution. This makes it unnecessary to resort to dividing the element in question into many smaller elements to obtain a satisfactory solution.
Reflection impulsivity perceptual decision‐making in patients with restless legs syndrome
Authors: Heim Beatrice , Pertl Marie‐Theres , Stefani Ambra , Heidbreder Anna , Zamarian Laura , Brandauer Elisabeth , Averbeck Bruno , Delazer Margarete , Seppi Klaus , Högl Birgit , Poewe Werner , Djamshidian Atbin 
Published: January 2018

AbstractObjectivesThe objective of this study was to investigate perceptual decision‐making and reflection impulsivity in drug naïve patients with restless legs syndrome (RLS) and patients with dopaminergic therapy.MethodsA total of 35 RLS patients (20 who were drug naïve regarding dopaminergic medication and 15 patients treated with dopaminergic therapy without augmentation or impulse control disorders) were included in this study. We used the Beads task and the Pixel task which assess reflection impulsivity and perceptual decision‐making, respectively. Results were compared to 20 healthy controls.ResultsBoth RLS patient groups gathered less evidence than healthy controls in the Beads task before making a decision (P < 0.001), but patients with dopaminergic treatment gathered less information than drug naïve patients (P = 0.026). Moreover, both patient groups made more choices against the evidence than healthy controls (both P < 0.01), but there was no difference between the two patient groups. In the Pixel task, we found an effect of task difficulty on reaction times with patients and controls responding faster with reduced task difficulty. There was neither an effect of group on reaction times nor an effect of group on error rates.ConclusionsReflection impulsivity is common in RLS patients, regardless whether they are drug naïve or treated with dopaminergic therapy. Thus, RLS patients tend to gather less information compared to healthy controls which could have a negative effect on decision‐making in daily life and should be investigated further.
Ethnographic Observational Study of the Biologic Initiation Conversation Between Rheumatologists and Biologic‐Naive Rheumatoid Arthritis Patients
Authors: Kottak Nicholas , Tesser John , Leibowitz Evan , Rosenberg Melissa , Parenti Dennis , DeHoratius Raphael 
Published: January 2018

ObjectiveThis ethnographic market research study investigated the biologic initiation conversation between rheumatologists and biologic‐naive patients with rheumatoid arthritis to assess how therapy options, particularly mode of administration, were discussed.MethodsConsenting rheumatologists (n = 16) and patients (n = 48) were videotaped during medical visits and interviewed by a trained ethnographer. The content, structure, and timing of conversations regarding biologic initiation were analyzed.ResultsThe mean duration of physician‐patient visits was approximately 15 minutes; biologic therapies were discussed for a mean of 5.6 minutes. Subcutaneous (SC) and intravenous (IV) therapy options were mentioned in 45 and 35 visits, respectively, out of a total of 48 visits. All patients had some familiarity with SC administration, but nearly half of patients (22 of 48) were unfamiliar with IV therapy going into the visit. IV administration was not defined or described by rheumatologists in 77% of visits (27 of 35) mentioning IV therapy. Thus, 19 of 22 patients who were initially unfamiliar with IV therapy remained unfamiliar after the visit. Disparities in physician‐patient perceptions were revealed, as all rheumatologists (16 of 16) believed IV therapy would be less convenient than SC therapy for patients, while 46% of patients (22 of 48) felt this way. In post‐visit interviews, some patients seemed confused and overwhelmed, particularly when presented with many treatment choices in a visit. Some patients stated they would benefit from visual aids or summary sheets of key points.ConclusionThis study revealed significant educational opportunities to improve the biologic initiation conversation and indicated a disparity between patients’ and rheumatologists’ perception of IV therapy.
Extrusion‐Based 3D Printing of Hierarchically Porous Advanced Battery Electrodes
Authors: Lacey Steven D. , Kirsch Dylan J. , Li Yiju , Morgenstern Joseph T. , Zarket Brady C. , Yao Yonggang , Dai Jiaqi , Garcia Laurence Q. , Liu Boyang , Gao Tingting , Xu Shaomao , Raghavan Srinivasa R. , Connell John W. , Lin Yi , Hu Liangbing 
Published: January 2018

AbstractA highly porous 2D nanomaterial, holey graphene oxide (hGO), is synthesized directly from holey graphene powder and employed to create an aqueous 3D printable ink without the use of additives or binders. Stable dispersions of hydrophilic hGO sheets in water (≈100 mg mL−1) can be readily achieved. The shear‐thinning behavior of the aqueous hGO ink enables extrusion‐based printing of fine filaments into complex 3D architectures, such as stacked mesh structures, on arbitrary substrates. The freestanding 3D printed hGO meshes exhibit trimodal porosity: nanoscale (4–25 nm through‐holes on hGO sheets), microscale (tens of micrometer‐sized pores introduced by lyophilization), and macroscale (<500 µm square pores of the mesh design), which are advantageous for high‐performance energy storage devices that rely on interfacial reactions to promote full active‐site utilization. To elucidate the benefit of (nano)porosity and structurally conscious designs, the additive‐free architectures are demonstrated as the first 3D printed lithium–oxygen (Li–O2) cathodes and characterized alongside 3D printed GO‐based materials without nanoporosity as well as nanoporous 2D vacuum filtrated films. The results indicate the synergistic effect between 2D nanomaterials, hierarchical porosity, and overall structural design, as well as the promise of a freeform generation of high‐energy‐density battery systems.
Precise Molecular Sieving Architectures with Janus Pathways for Both Polar and Nonpolar Molecules
Authors: Liu Jiangtao , Hua Dan , Zhang Yu , Japip Susilo , Chung Tai‐Shung 
Published: January 2018

AbstractPrecise molecular sieving architectures with Janus superhighways are constructed via a molecularly engineered interfacial reaction between cyclodextrin (CD) and trimesoyl chloride (TMC). Interestingly, the CD/TMC nanofilms constructed with both hydrophobic inner cavities and hydrophilic channels exhibit exceptionally high permeances for both polar and nonpolar solvents. The precise molecular sieving functions are determined by the type of CD building blocks and the inner cavities of intrinsic 3D hollow bowls. Positron annihilation spectroscopy (PAS) confirms that a larger inner CD cavity tends to generate a larger free volume and higher microporosity. Based on the rejection ratio of various dyes, the estimated molecular weight cutoff of CD/TMC nanofilms follows the trend of α‐CD/TMC (320 Da) <β‐CD/TMC (400 Da) <γ‐CD/TMC (550 Da), which is in strict accordance with the orders of their free volumes measured by PAS and inner cavity sizes of α‐CD <β‐CD <γ‐CD. This kind of novel CD/TMC molecular sieving membrane with intrinsic microporosity containing tunable pore size and sharp pore‐size distribution can effectively discriminate molecules with different 3D sizes.
High Detectivity and Transparent Few‐Layer MoS2/Glassy‐Graphene Heterostructure Photodetectors
Authors: Xu Hao , Han Xiaoyu , Dai Xiao , Liu Wei , Wu Jiang , Zhu Juntong , Kim Dongyoung , Zou Guifu , Sablon Kimberley A. , Sergeev Andrei , Guo Zhengxiao , Liu Huiyun 
Published: January 2018

AbstractLayered van der Waals heterostructures have attracted considerable attention recently, due to their unique properties both inherited from individual two‐dimensional (2D) components and imparted from their interactions. Here, a novel few‐layer MoS2/glassy‐graphene heterostructure, synthesized by a layer‐by‐layer transfer technique, and its application as transparent photodetectors are reported for the first time. Instead of a traditional Schottky junction, coherent ohmic contact is formed at the interface between the MoS2 and the glassy‐graphene nanosheets. The device exhibits pronounced wavelength selectivity as illuminated by monochromatic lights. A responsivity of 12.3 mA W−1 and detectivity of 1.8 × 1010 Jones are obtained from the photodetector under 532 nm light illumination. Density functional theory calculations reveal the impact of specific carbon atomic arrangement in the glassy‐graphene on the electronic band structure. It is demonstrated that the band alignment of the layered heterostructures can be manipulated by lattice engineering of 2D nanosheets to enhance optoelectronic performance.
Material Design of p‐Type Transparent Amorphous Semiconductor, Cu–Sn–I
Authors: Jun Taehwan , Kim Junghwan , Sasase Masato , Hosono Hideo 
Published: January 2018

AbstractTransparent amorphous semiconductors (TAS) that can be fabricated at low temperature are key materials in the practical application of transparent flexible electronics. Although various n‐type TAS materials with excellent performance, such as amorphous In‐Ga‐Zn‐O (a‐IGZO), are already known, no complementary p‐type TAS has been realized to date. Here, a material design concept for p‐type TAS materials is proposed utilizing the pseudo s‐orbital nature of spatially spreading iodine 5p orbitals and amorphous Sn‐containing CuI (a‐CuSnI) thin film is reported as an example. The resulting a‐CuSnI thin films fabricated by spin coating at low temperature (140 °C) have a smooth surface. The Hall mobility increases with the hole concentration and the largest mobility of ≈9 cm2 V−1 s−1 is obtained, which is comparable with that of conventional n‐type TAS.