bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trapped planetary (Rossby) waves observed in the Indian Ocean by satellite borne altimeters
Authors: De-Leon Yair , Paldor Nathan 
Published: June 2017

Abstract. Using 20 years of accurately calibrated, high-resolution observations of sea surface height anomalies (SSHAs) by satellite borne altimeters, we show that in the Indian Ocean south of the Australian coast the low-frequency variations of SSHAs are dominated by westward propagating, trapped, i.e., non-harmonic, Rossby (Planetary) waves. Our results demonstrate that the meridional-dependent amplitudes of the SSHAs are large only within a few degrees of latitude next to the southern Australian coast while farther in the ocean they are uniformly small. This meridional variation of the SSHA signal is typical of the amplitude structure in the trapped wave theory. The westward propagation speed of the SSHA signal is analyzed by employing three different methods of estimation. Each one of these methods yields speed estimates that can vary widely between adjacent latitudes but the combination of at least two of the three methods yields much smoother variation. The estimates obtained in this manner show that the observed phase speeds at different latitudes exceed the phase speeds of harmonic Rossby (planetary) waves by 140 to 200 % (which was also reported in previous studies). In contrast, the theory of trapped Rossby (planetary) waves in a domain bounded by a wall on its equatorward side yields phase speeds that approximate more closely the observed phase speeds in the study area.
Universal antiretroviral therapy for HIV‐infected children: a review of the benefits and risks to consider during implementation
Authors: Barlow‐Mosha Linda , Musiime Victor , Davies Mary‐Ann , Prendergast Andrew J. , Musoke Philippa , Siberry George , Penazzato Martina 
Published: June 2017

AbstractBackground: The 2016 World Health Organization (WHO) consolidated guidelines on the use of antiretroviral drugs for treating and preventing HIV infection, recommended to start all HIV‐infected children on antiretroviral therapy (ART). Here, we explore the possible benefits and risks of implementing universal ART for all HIV‐infected children and adolescents and outline some of the key considerations that led to the 2016 revision of WHO guidelines.Methods: We conducted a review of the published data from 2000 to 2016, to ascertain the clinical and programmatic benefits, as well as the risks of implementing universal ART for all children.Results and discussion: Universal ART for all children has the potential to increase treatment coverage, which in 2015 was only 51% globally, as well as providing several biological benefits, by preventing: premature death/loss to follow‐up, progressive destruction of the immune system, poor growth and pubertal delay, poor neuro‐cognitive outcomes and future burden to the health care system with complications of untreated HIV‐infection. However, the strategy could be associated with risks, notably development of HIV drug resistance, antiretroviral drug toxicities and increased costs to an already stretched health system.Conclusion: Overall, our findings suggest that the benefits could outweigh the risks and support universal ART for all HIV‐infected children, but recognize that national programmes will need to put measures in place to minimize the risks if they choose to implement the strategy.
Climate, soil or both? Which variables are better predictors of the distributions of Australian shrub species?
Authors: Hageer Yasmin , Esperón-Rodríguez Manuel , Baumgartner John B. , Beaumont Linda J. 
Published: June 2017

BackgroundShrubs play a key role in biogeochemical cycles, prevent soil and water erosion, provide forage for livestock, and are a source of food, wood and non-wood products. However, despite their ecological and societal importance, the influence of different environmental variables on shrub distributions remains unclear. We evaluated the influence of climate and soil characteristics, and whether including soil variables improved the performance of a species distribution model (SDM), Maxent.MethodsThis study assessed variation in predictions of environmental suitability for 29 Australian shrub species (representing dominant members of six shrubland classes) due to the use of alternative sets of predictor variables. Models were calibrated with (1) climate variables only, (2) climate and soil variables, and (3) soil variables only.ResultsThe predictive power of SDMs differed substantially across species, but generally models calibrated with both climate and soil data performed better than those calibrated only with climate variables. Models calibrated solely with soil variables were the least accurate. We found regional differences in potential shrub species richness across Australia due to the use of different sets of variables.ConclusionsOur study provides evidence that predicted patterns of species richness may be sensitive to the choice of predictor set when multiple, plausible alternatives exist, and demonstrates the importance of considering soil properties when modeling availability of habitat for plants.
Experimental constraints on the rheology, eruption, and emplacement dynamics of analog lavas comparable to Mercury's northern volcanic plains
Authors: Vetere F. , Rossi S. , Namur O. , Morgavi D. , Misiti V. , Mancinelli P. , Petrelli M. , Pauselli C. , Perugini D. 
Published: June 2017

AbstractWe present new viscosity measurements of a synthetic silicate system considered an analogue for the lava erupted on the surface of Mercury. In particular, we focus on the northern volcanic plains (NVP), which correspond to the largest lava flows on Mercury and possibly in the Solar System. High‐temperature viscosity measurements were performed at both superliquidus (up to 1736 K) and subliquidus conditions (1569–1502 K) to constrain the viscosity variations as a function of crystallinity (from 0 to 28%) and shear rate (from 0.1 to 5 s−1). Melt viscosity shows moderate variations (4–16 Pa s) in the temperature range of 1736–1600 K. Experiments performed below the liquidus temperature show an increase in viscosity as shear rate decreases from 5 to 0.1 s−1, resulting in a shear thinning behavior, with a decrease in viscosity of ~1 log unit. The low viscosity of the studied composition may explain the ability of NVP lavas to cover long distances, on the order of hundreds of kilometers in a turbulent flow regime. Using our experimental data we estimate that lava flows with thickness of 1, 5, and 10 m are likely to have velocities of 4.8, 6.5, and 7.2 m/s, respectively, on a 5° ground slope. Numerical modeling incorporating both the heat loss of the lavas and its possible crystallization during emplacement allows us to infer that high effusion rates (>10,000 m3/s) are necessary to cover the large distances indicated by satellite data from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft.
Partitioning sediment flux by provenance and tracing erosion patterns in Taiwan
Authors: Resentini Alberto , Goren Liran , Castelltort Sébastien , Garzanti Eduardo 
Published: June 2017

AbstractWe critically evaluate the potential and limitations of an alternative way to calculate erosion rates based on petrographic and mineralogical fingerprints of fluvial sediments coupled with gauged sediment fluxes. Our approach allows us to apportion sediment loads to different lithological units, and consequently to discriminate erosion rates in different tectonic domains within each catchment. Our provenance data on modern Taiwanese sands indicate focused erosion in the Backbone Range and Tananao Complex of the retrowedge. Lower rates are inferred for the northern part of the island characterized by tectonic extension and for the western foothills in the prowedge. The principal factor of uncertainty affecting our estimates is the inevitably inaccurate evaluation of total sediment load, because only the suspended flux was measured. Another is the assumption that suspended load and bed load are derived from the same sources in fixed proportions. Additional errors are caused by the insufficiently precise definition of lithologically similar compositional end‐members and by the temporal variability of sediment composition at the outlet of each catchment related to the spatial variability of erosional processes and triggering agents such as earthquakes, typhoons, and landslides. To evaluate the robustness of our findings, we applied a morphometric technique based on the stream‐power model. The results obtained are broadly consistent, with local discrepancies ascribed to poorly constrained assumptions and choices of scaling parameters. Our local erosion estimates are consistent with GPS uplift rates measured on a decadal timescale and generally higher than basin‐wide results inferred from cosmogenic‐nuclide and thermochronology data.
Should we mine the deep seafloor?
Authors: Beaulieu Stace E. , Graedel T. E. , Hannington Mark D. 
Published: June 2017

AbstractAs land‐based mineral resources become increasingly difficult and expensive to acquire, the potential for mining resources from the deep seafloor has become widely discussed and debated. Exploration leases are being granted, and technologies are under development. However, the quantity and quality of the resources are uncertain, and many worry about risks to vulnerable deep‐sea ecosystems. Deep‐sea mining has become part of the discussion of the United Nations Sustainable Development Goals. In this article we provide a summary of benefits, costs, and uncertainties that surround this potentially attractive but contentious topic.
A new solar wind‐driven global dynamic plasmapause model: 2. Model and validation
Authors: He Fei , Zhang Xiao‐Xin , Lin Rui‐Lin , Fok Mei‐Ching , Katus Roxanne M. , Liemohn Mike W. , Gallagher Dennis L. , Nakano Shinya 
Published: June 2017

AbstractA new solar wind‐driven global dynamic plasmapause (NSW‐GDP) model has been constructed based on the largest currently available database containing 49,119 plasmapause crossing locations and 3957 plasmapause profiles (corresponding to 48,899 plasmapause locations), from 18 satellites during 1977–2015 covering four solar cycles. This model is compiled by the Levenberg‐Marquardt method for nonlinear multiparameter fitting and parameterized by VSW, BZ, SYM‐H, and AE. Continuous and smooth magnetic local time dependence controlled mainly by the solar wind‐driven convection electric field ESW is also embedded in this model. Compared with previous empirical models based on our database, this new model improves the forecasting accuracy and capability for the global plasmapause. The diurnal, seasonal, and solar cycle variations of the plasmapause can be captured by the new model. The NSW‐GDP model can potentially be used to forecast the global plasmapause shape with upstream solar wind and interplanetary magnetic field parameters and corresponding predicted values of SYM‐H and AE and can also be used as input parameters for other inner magnetospheric coupling models, such as dynamic radiation belt and ring current models and even MHD models.
Titan's ionosphere: A survey of solar EUV influences
Authors: Shebanits O. , Vigren E. , Wahlund J.‐E. , Holmberg M. K. G. , Morooka M. , Edberg N. J. T. , Mandt K. E. , Waite J. H. 
Published: June 2017

AbstractEffects of solar EUV on positive ions and heavy negative charge carriers (molecular ions, aerosol, and/or dust) in Titan's ionosphere are studied over the course of almost 12 years, including 78 flybys below 1400 km altitude between TA (October 2004) and T120 (June 2016). The Radio and Plasma Wave Science/Langmuir Probe‐measured ion charge densities (normalized by the solar zenith angle) show statistically significant variations with respect to the solar EUV flux. Dayside charge densities increase by a factor of ≈2 from solar minimum to maximum, while nightside charge densities are found to anticorrelate with the EUV flux and decrease by a factor of ≈3–4. The overall EUV dependence of the ion charge densities suggest inapplicability of the idealized Chapman theory below 1200 km in Titan's ionosphere. Nightside charge densities are also found to vary along Titan's orbit, with higher values in the sunward magnetosphere of Saturn compared to the magnetotail.
Ion velocity distributions in dipolarization events: Distributions in the central plasma sheet
Authors: Birn J. , Runov A. , Zhou X.‐Z. 
Published: June 2017

AbstractUsing combined MHD/test particle simulations, we further explore characteristic ion velocity distributions in the central plasma sheet (CPS) in relation to dipolarization events. Distributions in the CPS within the dipolarized flux bundle (DFB) that follows the passage of a dipolarization front typically show two opposing low subthermal‐energy beams with a ring‐like component perpendicular to the magnetic field at about twice the thermal energy. The dominance of the perpendicular anisotropy and a field‐aligned peak at lower energy agree qualitatively with ion distribution functions derived from “Time History of Events and Macroscale Interactions during Substorms” observations. At locations somewhat off the equatorial plane the field‐aligned peaks are shifted by a field‐aligned component of the bulk flow, such that one peak becomes centered near zero net velocity, which makes it less likely to be observed. The origins of the field‐aligned peaks are low‐energy lobe (or near plasma sheet boundary layer) regions, while the ring distribution originates mostly from thermal plasma sheet particles on extended field lines. The acceleration mechanisms are also quite different: the beam ions are accelerated first by the E × B drift motion of the DFB and then by a slingshot effect of the earthward convecting DFB (akin to first‐order Fermi, type B, acceleration), which causes an increase in field‐aligned speed. In contrast, the ring particles are accelerated by successive, betatron‐like acceleration after entering the high electric field region of an earthward propagating DFB.
Competition between uplift and transverse sedimentation in an experimental delta
Authors: Grimaud Jean‐Louis , Paola Chris , Ellis Chris 
Published: June 2017

AbstractMass is commonly injected into alluvial systems either laterally by transport from source regions or vertically from below via local uplift. We report results on the competition between these two fundamental processes, using an experimental basin with a deformable substrate. The lateral supply is via two alluvial fans on orthogonal walls of the basin; the uplifting region is downstream of one of the fans (axial) and opposite to the other (transverse). We show that the presence of a transverse sediment input increases the erosion rate of the uplifting region by pushing the mixing zone between the two alluvial sources against the uplifting mass. However, increase in sediment delivery to the transverse fan does not cause a proportional increase in erosion rate of the uplifting region. Instead, the system reaches a steady state balance between uplift and erosion induced by the transverse fan, such that there is no change in the total mass above the active alluvial surface—a lateral analog of the classical steady state between vertical erosion and uplift. We also show that the mixing zone is instrumental in limiting upstream aggradation and funneling sediments to the shore, resulting in limited river lateral mobility and increased shoreline progradation. Hence, the interaction between alluvial sources buffers river erosion and leads to consistent deviations from predictions of the area of influence of each fan based on simple mass‐balance arguments. In the Ganges‐Brahmaputra‐Meghna delta, we suggest that similar dynamics help stabilize the Brahmaputra River course in the Jamuna Valley during Holocene time.
Methodology for time‐domain estimation of storm time geoelectric fields using the 3‐D magnetotelluric response tensors
Authors: Kelbert Anna , Balch Christopher C. , Pulkkinen Antti , Egbert Gary D. , Love Jeffrey J. , Rigler E. Joshua , Fujii Ikuko 
Published: June 2017

AbstractGeoelectric fields at the Earth's surface caused by magnetic storms constitute a hazard to the operation of electric power grids and related infrastructure. The ability to estimate these geoelectric fields in close to real time and provide local predictions would better equip the industry to mitigate negative impacts on their operations. Here we report progress toward this goal: development of robust algorithms that convolve a magnetic storm time series with a frequency domain impedance for a realistic three‐dimensional (3‐D) Earth, to estimate the local, storm time geoelectric field. Both frequency domain and time domain approaches are presented and validated against storm time geoelectric field data measured in Japan. The methods are then compared in the context of a real‐time application.
Comment on “Rescaling the complementary relationship for land surface evaporation” by R. Crago et al.
Authors: Ma Ning , Zhang Yinsheng 
Published: June 2017

AbstractThe generalized complementary relationship (GCR) model of Brutsaert (2015) has been widely applied to estimate land surface evapotranspiration (E) over Chinese eastern monsoon region, Loess Plateau and Australia. However, Crago et al. (2016, hereinafter C16) recently noted a deficiency in one of his boundary conditions and proposed a novel approach to improve it. The key of this approach is to determine the ratio (xmin) of the potential evapotranspiration (Epo) to the apparent potential evapotranspiration for an entirely dry surface (Epads) at which E tends to be vanishing. As seen, the physically reasonable range of xmin should be between 0 and 1. The present comment reports that the xmin in C16 may become invalid under conditions of relatively strong available energy but weak winds if Epads is calculated by the mass‐transfer‐based method, thereby causing unrealistic estimation of E. A more preferable way to determine Epads is still based on the traditional Penman‐based equation with consideration of the characteristics of dry air in which Epads occurs.
A Carborane‐Containing Fluorophore as a Stain of Cellular Lipid Droplets
Authors: Wu Andrew , Kolanowski Jacek L. , Boumelhem Badwi B. , Yang Kylie , Lee Rebecca , Kaur Amandeep , Fraser Stuart T. , New Elizabeth J. , Rendina Louis M. 
Published: June 2017

AbstractThe use of fluorescent markers and probes greatly enhances biological investigations but relies on the provision of an array of fluorophores with diverse properties. Herein we report a novel carborane‐containing coumarin, 5, which is sufficiently lipophilic to localise in cellular lipid droplets. In non‐polar solvents which show comparable polarities to those of a lipid environment, compound 5 exhibits a fluorescence quantum yield two orders of magnitude greater than found in aqueous solvents, adding a further degree of selectivity to lipid droplet imaging. Compound 5 can stain lipid droplets in ex vivo adipocytes as well as in cultured cells, and can be utilised in flow cytometry as well as confocal microscopy.
Auditory processing in autism spectrum disorder: Mismatch negativity deficits
Authors: Vlaskamp Chantal , Oranje Bob , Madsen Gitte Falcher , Møllegaard Jepsen Jens Richardt , Durston Sarah , Cantio Cathriona , Glenthøj Birte , Bilenberg Niels 
Published: June 2017

Children with autism spectrum disorders (ASD) often show changes in (automatic) auditory processing. Electrophysiology provides a method to study auditory processing, by investigating event‐related potentials such as mismatch negativity (MMN) and P3a‐amplitude. However, findings on MMN in autism are highly inconsistent, partly due to small sample sizes in the studies and differences in MMN paradigms. Therefore, in the current study, MMN and P3a amplitude were assessed in a relatively large sample of children with ASD, using a more extensive MMN paradigm and compared with that of typically developing children (TDC). Thirty‐five children (aged 8–12 years) with ASD and 38 age and gender matched TDC were assessed with a MMN paradigm with three types of deviants, i.e., frequency, duration and a combination of these two. MMN elicited by duration and frequency‐duration deviants was significantly reduced in the ASD group. P3a‐amplitude elicited by duration deviants was significantly increased in the ASD group. Reduced MMN in children with ASD suggests that children with ASD may be less responsive to environmentally deviant stimuli at an early (sensory) level. P3a‐amplitude was increased in ASD, implying a hyper‐responsivity at the attentional level. In addition, as similar MMN deficits are found in schizophrenia, these MMN results may explain some of the frequently reported increased risk of children with ASD to develop schizophrenia later in life. Autism Res 2017, 10: 1857–1865. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.Lay SummaryAutomatic detection of deviant sounds in the environment, such as upcoming traffic, is often affected in children with autism spectrum disorders (ASD). Mismatch negativity (MMN) is a way to quantify automatic deviancy detection, using electroencephalography. In this study, auditory MMN was assessed in 35 children with ASD and 38 matched control children, revealing significantly reduced MMN in the ASD group. This may indicate that children with ASD are less able to automatically detect environmentally deviant stimuli.
Improving thermostability of (R)‐selective amine transaminase from Aspergillus terreus through introduction of disulfide bonds
Authors: Xie Dong‐Fang , Fang Hui , Mei Jia‐Qi , Gong Jin‐Yan , Wang Hong‐Peng , Shen Xiu‐Ying , Huang Jun , Mei Le‐He 
Published: June 2017

AbstractTo improve the thermostability of (R)‐selective amine transaminase from Aspergillus terreus (AT‐ATA), we used computer software Disulfide by Design and Modelling of Disulfide Bonds in Proteins to identify mutation sites where the disulfide bonds were most likely to form. We obtained three stabilized mutants (N25C‐A28C, R131C‐D134C, M150C‐M280C) from seven candidates by site‐directed mutagenesis. Compared to the wild type, the best two mutants N25C‐A28C and M150C‐M280C showed improved thermal stability with a 3.1‐ and 3.6‐fold increase in half‐life (t1/2) at 40 °C and a 4.6 and 5.1 °C increase in T5010. In addition, the combination of mutant R131C‐D134C and M150C‐M280C displayed the largest shift in thermostability with a 4.6‐fold increase in t1/2 at 40 °C and a 5.5 °C increase in T5010. Molecular dynamics simulation indicated that mutations of N25C‐A28C and M150C‐M280C lowered the overall root mean square deviation for the overall residues at elevated temperature and consequently increased the protein rigidity. The stabilized mutation of R131C‐D134C was in the region of high mobility and on the protein surface, and the disulfide bond constraints the flexibility of loop 121–136.