bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Thunderstorm Identification Method Combining the Area of Graupel Distribution Region and Weather Radar Reflectivity
Authors: Yang B. , Gao X. , Han Y. , Zhang Y. , Gao T. 
Published: November 2019

AbstractThunderstorm identification from weather radar data remains a fundamental problem in lightning nowcasting. In this study, a novel thunderstorm identification method combining the area of graupel distribution region and weather radar reflectivity is proposed. To optimize identification parameters of the identification method, the radar echoes with 312 thunderstorms in 17 weather processes in Nanjing area, China, from 2014 to 2015 were identified and tested to obtain the optimal identification parameters. The results indicate that the optimal parameter combination is to set the storm region identification reflectivity threshold at 0°C isothermal level to 30 dBZ and set the area of graupel distribution region to 2 km2. With such a parameter combination, the optimal identification results with the probability of detection of 91%, false alarm rate of 6.9%, and critical success index of 85.3% could be obtained. Moreover, the proposed thunderstorm identification method can also provide effective means for thunderstorm nowcasting.
An Automatic Rainfall‐Type Classification Algorithm Combining Diverse 3‐D Features of Radar Echoes
Authors: Lei Bo , Xu Zi‐Xin , Yang Ling , Li Xuehua , Zhen Xiaoqiong 
Published: November 2019

AbstractThis paper proposes an improved algorithm which combines neural networks with diverse 3‐D structural features to partition radar reflectivity into convective and stratiform precipitation types. Radar data used in this work were obtained from three networked X‐band Doppler radars located in Chengdu, China. The proposed algorithm consists of the two sections: six high‐resolution features, which could be extracted from radar volume scanning and expressed the characteristics of the target in many ways, are selected as input to the neural network; systematic self‐diagnosis is implemented; and the optimized model is determined according to analysis of bias and variance of classifier. Three state‐of‐art classification algorithms were implemented as references for algorithm evaluation. Both subjective comparison and statistical results convince that performance of the proposed algorithm is better than performance of traditional classification algorithms in various weather systems. The statistical results show that the proposed algorithm F‐score values are 3%, 24%, and 30% higher than the fuzzy logic, SHY95, and BL algorithms and the recognition speed of the proposed algorithm is 54 times, two times, and four times that of fuzzy logic, SHY95, and BL, respectively. Considering network training is an offline procedure, classification by proposed neural network algorithm has great potential in real‐time weather analysis for the precipitation classification.
An Improved Method for Determining Near‐Surface Currents From Wave Dispersion Measurements
Authors: Smeltzer B. K. , Æsøy E. , Ådnøy A. , Ellingsen S. Å. 
Published: November 2019

AbstractA new inversion method for determining near‐surface shear currents from a measured wave spectrum is introduced. The method is straightforward to implement and starts from the existing state‐of‐the‐art technique of assigning effective depths to measured wavenumber‐dependent Doppler shift velocities. A polynomial fit is performed, with the coefficients scaled based on a simple derived relation to produce a current profile that is an improved estimate of the true profile. The method involves no user‐input parameters, with the optimal parameters involved in the polynomial fit being chosen based on a simple criterion involving the measured Doppler shift data only. The method is tested on experimental data obtained from a laboratory where current profiles of variable depth dependence could be created and measured by particle image velocimetry, which served as “truth” measurements. Applying the new inversion method to experimentally measured Doppler shifts resulted in a >3 times improvement in accuracy relative to the state of the art for current profiles with significant near‐surface curvature. The experiments are dynamically similar to typical oceanographic flows such as wind‐drift profiles, and our laboratory thus makes a suitable and eminently useful scale model of the real‐life setting. Our results show that the new method can achieve improved accuracy in reconstructing near‐surface shear profiles from wave measurements by a simple extension of methods, which are currently in use, incurring little extra complexity and effort. A novel adaptation of the normalized scalar product method has been implemented, able to extract Doppler shift velocities as a function of wavenumber from the measured wave spectrum.
On the Variability of Arabian Sea Mixing and its Energetics
Authors: Singh Shikha , Valsala Vinu , Prajeesh A. G. , Balasubramanian Sridhar 
Published: November 2019

AbstractThe mechanism of interannual variability of Arabian Sea (AS) mixing is studied by examining its energetics from 60 years of model output (1950–2009) generated using an ocean general circulation model. The model results are compared with ocean reanalysis data for the same period. Both model and reanalysis data show consistent patterns of interannual variability of AS mixing. It is observed that the dominant mode of interannual variability has a basin‐wide structure with monotonic sign throughout the basin, albeit with a higher intensity in the central and southeast regions of the AS. The variability is primarily controlled by El Ni
o‐Southern Oscillation with shallower (deeper) mixed layer during El Ni
o (La Ni
a). During a typical La Ni
a year, the wind stress forcing, heat fluxes, and evaporation minus precipitation together cause deepening of mixed layer depth (MLD) in AS. This MLD variability has the strongest signal in winter months (i.e., December to February [DJF]). Further, the resolved mixing energetics suggest that the dominant forcing of MLD variability changes with seasons and has a regional preference. Buoyancy production of turbulent kinetic energy (TKE) governs the mixing and associated MLD variability in central AS during September to November (SON) and in northeast AS during DJF. Both buoyancy and mechanical production of TKE govern MLD variability in southwest to central AS from June to August and southeast AS in SON. Thus, the study highlights basin‐wide structure of interannual variability of AS mixing along with its controlling mechanisms with strong regional dependency owing to the contrasting nature of forcing prevailing over various parts of the AS.
On the Accuracy of Reconstructing Plasma Sheet Electron Fluxes From Temperature and Density Models
Authors: Dubyagin S. , Ganushkina N. , Liemohn M. 
Published: November 2019

AbstractThe particle simulations of the inner magnetosphere require time‐dependent boundary conditions for the particle flux set in the transition region between dipolar and tail‐like configurations. Usually, the flux is reconstructed from particle density and temperature predicted by empirical models or magnetohydrodynamic simulations. However, this method requires assumptions about the energy spectra to be made. This uncertainty adds to the inaccuracy of the empirical models or magnetohydrodynamic predictions. We use electron flux measurements in the nightside at r=6–11RE in the 1–300 keV energy range to estimate the potential accuracy of the electron flux reconstruction from the macroscopic plasma parameter models. We use kappa and Maxwellian distribution functions as well as two population approximations to describe the electron spectra. It is found that this method works reasonably well in the thermal energy range (1–10 keV). However, the average difference between measured and predicted fluxes becomes as large as 1 order of magnitude at energies ≥40 keV. The optimal value of the kappa parameter is found to be between 3 and 4, but it depends strongly on magnetic local time and radial distance. We conclude that the development of the flux‐based models (model of differential flux at several reference energies) instead of density and temperature models can be considered as a promising direction.
Copula Theory as a Generalized Framework for Flow‐Duration Curve Based Streamflow Estimates in Ungaged and Partially Gaged Catchments
Authors: Worland Scott. C. , Steinschneider Scott , Farmer William , Asquith William , Knight Rodney 
Published: November 2019

AbstractFlow‐duration curve (FDC) based streamflow estimation methods involve estimating an FDC at an ungaged or partially gaged location and using the time series of nonexceedance probabilities estimated from donor streamgage sites to generate estimates of streamflow. We develop a mathematical framework to illustrate the connection between copulas and prior FDC‐based approaches. The performance of copula methods is compared to several other streamflow estimation methods using a decade of daily streamflow data from 74 sites located within two river basins in the southeast United States with different climate characteristics and physiographic properties. We show that copula approaches: (1) outperform other methods in the limiting case of perfect information with regard to the rank‐based correlation structure and FDCs across the gaging network; (2) provide a hedge against poor performance when donor information becomes sparser and less informative; (3) outperform other methods when used for partially gaged sites with several years of available data; and (4) remain a competitive albeit nondominating method for ungaged sites and partially gaged sites with limited data when realistic error is introduced in the estimation of FDCs and correlations across the gaging network.
Regressed Models for Multirate Mass Transfer in Heterogeneous Media
Authors: Elenius Maria T. , Abriola Linda M. 
Published: November 2019

AbstractSeveral applications to flow and transport in sorptive porous media are fundamentally dependent on the heterogeneous medium properties. This poses a challenge for direct numerical simulations, as fine grids are needed. One alternative approach is the application of the multirate mass transfer (MRMT) method. In this approach, rather than explicitly modeling immobile regions, such as clay layers, the solute concentration in these regions is treated by explicit state variables, and the transport between mobile and immobile regions is modeled by first‐order exchange terms. In the implementation of this approach, fine‐scale simulations on subdomains are often necessary to develop appropriate parameters, since regressed models for the estimation of these parameters, based on a priori data, are unavailable. To facilitate applications of MRMT to three‐dimensional heterogeneous media at the field scale, in this work, upscaled parameters needed for a two‐rate MRMT model are fit to several hundred three‐dimensional fine‐scale simulations by employing a two‐step fitting procedure. The fitted parameters are then regressed with respect to geostatistical, sorptive, and flow parameters. Upscaled simulations using the fitted and the regressed parameters produce breakthrough curves that are very similar to fine‐scale curves. The data used to regress the parameters span a range of heterogeneous properties and flow conditions, and the model is demonstrated to be robust to untested parameter values and initial and boundary conditions. These developed regressions can be employed to efficiently account for back‐diffusion and desorption in future modeling of transport in heterogeneous media without the need to perform fine‐scale simulations.
Mimicking Geologic Depositional Fabrics for Multiphase Flow Experiments
Authors: Krishnamurthy Prasanna G. , Meckel Tip A. , DiCarlo David 
Published: November 2019

AbstractA novel laboratory technique is presented for generating two‐dimensional beadpacks with reproducible natural geologic sedimentary bedforms. The heterogeneous beadpacks are deposited in a 0.6 m × 0.6 m × 0.02 m glass slab chamber using a programmable two‐axis linear actuator. The method takes advantage of natural mechanical sorting processes, along with the ability to program the motion of the arm, to efficiently build cross‐beds and ripple laminae similar to those seen in natural water‐lain clastic deposits. By using a mixture of grain sizes (200 to 800 μm diameter), depositional fabrics with multiscale heterogeneity (mm to dm) are generated. Reproducibility tests show very high correlation among multiple fabric realizations produced with similar inputs. After introducing this first‐of‐a‐kind capability to produce depositionally realistic fabrics at scales larger than that of rock cores, a demonstrative study is presented that illustrates gravity unstable multiphase flow which is relevant in the context of CO2 sequestration. Preliminary results highlight the dramatic impact small scale capillary heterogeneities have on multiphase immiscible displacement and can help bridge understanding between core scale experiments and reservoir scale observations.
Proneness of European Catchments to Multiyear Streamflow Droughts
Authors: Brunner Manuela I. , Tallaksen Lena M. 
Published: November 2019

AbstractDroughts can have severe ecological, social, and economic impacts. Some impacts are particularly severe if droughts last longer than 1 year and water stores are not fully replenished. The proneness of European catchments to multiyear droughts has not been studied extensively, even though such events pose a great challenge for water resources management in many regions. In this study, we assess regions and catchments in Europe that might be prone to multiyear droughts by stochastically simulating long discharge records. The simulation approach uses phase randomization and the flexible, four‐parameter kappa distribution to generate potential realizations of (long) drought events. Both observed and stochastically simulated series are used to identify multiyear drought events. Catchments prone to multiyear droughts are located in southern France, central Europe, and southwestern England. To assess potential future changes in the proneness to multiyear events, we follow a purely empirical approach. We link the proneness of a catchment to multiyear events to its low‐flow regime as described by the seasonality ratio. Our results show that catchments with a melt‐dominated flow regime are generally not affected by multiyear droughts, whereas many catchments with a rainfall‐dominated flow regime show such proneness. We further find that catchments experiencing regime changes toward a rainfall‐dominated flow regime might be more affected by multiyear droughts in the future. Overall, four regions stood out that might potentially become more affected in the future if historical trends in regimes continue: southeastern England, southeastern France, central Norway, and the Pre‐Alps.
Effect of topiramate on eating behaviours in Prader-Willi syndrome: TOPRADER double-blind randomised placebo-controlled study
Authors: Consoli Angèle , Çabal Berthoumieu Sophie , Raffin Marie , Thuilleaux Denise , Poitou Christine , Coupaye Muriel , Pinto Graziella , Lebbah Said , Zahr Noel , Tauber Maïthé , Cohen David , Bonnot Olivier 
Published: November 2019

AbstractPrader–Willi Syndrome (PWS) is a rare genetic syndrome leading to severe behavioural disorders and mild cognitive impairment. The objective of this double-blind randomised placebo-controlled trial was to study the efficacy and tolerance of topiramate on behavioural disorders in patients with PWS. Participants (aged 12–45 years) had genetically confirmed PWS and severe irritability/impulsivity, eating disorders and/or obesity, and skin picking. Thirty-two participants received a placebo (PBO), and 30 participants received topiramate (TOP) (50–200 mg/day) for 8 weeks. The primary outcome was the rate of responders using the Clinical Global Impression-Improvement (CGI-I) scale. The secondary outcome measures included the Aberrant Behaviour Checklist, the Dykens Hyperphagia Questionnaire (DHK), the Self-Injurious Behaviour Scale (SIBS) and the body mass index (BMI). We found no significant difference in the primary outcome (the CGI-I): 9 (30%) patients were very much or much improved in the TOP group compared to 7 (22.6%) patients in the PBO group. However, the DHK behaviour and severity scores improved significantly more over time in patients treated with topiramate versus those receiving a placebo, with a significant dose–effect relationship. DHK scores were also significantly associated with genetic subtypes and hospitalisation status. The effects of topiramate on eating behaviours remained significant after adjusting for genetic subtype and hospitalisation. Topiramate had therefore a significant effect on eating disorders, with a dose–effect relationship. Given the burden of eating disorders in PWS, we believe that topiramate may become the first psychotropic option within the global care of obesity in individuals with PWS.
A protective role for N-acylphosphatidylethanolamine phospholipase D in 6-OHDA-induced neurodegeneration
Authors: Palese Francesca , Pontis Silvia , Realini Natalia , Piomelli Daniele 
Published: November 2019

AbstractN-acylphosphatidylethanolamine phospholipase D (NAPE-PLD) catalyzes the cleavage of membrane NAPEs into bioactive fatty-acid ethanolamides (FAEs). Along with this precursor role, NAPEs might also serve autonomous signaling functions. Here, we report that injections of 6-hydroxydopamine (6-OHDA) into the mouse striatum cause a local increase in NAPE and FAE levels, which precedes neuronal cell death. NAPE, but not FAE, accumulation is enhanced in mice lacking NAPE-PLD, which display a substantial reduction in 6-OHDA-induced neurotoxicity, as shown by increased survival of substantia nigra dopamine neurons, integrity of striatal dopaminergic fibers, and striatal dopamine metabolite content. Reduced damage is accompanied by attenuation of the motor response evoked by apomorphine. Furthermore, NAPE-PLD silencing protects cathecolamine-producing SH-SY5Y cells from 6-OHDA-induced reactive oxygen species formation, caspase-3 activation and death. Mechanistic studies in mice suggest the existence of multiple molecular contributors to the neuroprotective effects of NAPE-PLD deletion, including suppression of Rac1 activity and attenuated transcription of several genes (Cadps, Casp9, Egln1, Kcnj6, Spen, and Uchl1) implicated in dopamine neuron survival and/or Parkinson’s disease. The findings point to a previously unrecognized role for NAPE-PLD in the regulation of dopamine neuron function, which may be linked to the control of NAPE homeostasis in membranes.
Neutrophils promote venular thrombosis by shaping the rheological environment for platelet aggregation
Authors: Puhr-Westerheide Daniel , Schink Severin J. , Fabritius Matthias , Mittmann Laura , Hessenauer Maximilian E. T. , Pircher Joachim , Zuchtriegel Gabriele , Uhl Bernd , Holzer Martin , Massberg Steffen , Krombach Fritz , Reichel Christoph A. 
Published: November 2019

AbstractIn advanced inflammatory disease, microvascular thrombosis leads to the interruption of blood supply and provokes ischemic tissue injury. Recently, intravascularly adherent leukocytes have been reported to shape the blood flow in their immediate vascular environment. Whether these rheological effects are relevant for microvascular thrombogenesis remains elusive. Employing multi-channel in vivo microscopy, analyses in microfluidic devices, and computational modeling, we identified a previously unanticipated role of leukocytes for microvascular clot formation in inflamed tissue. For this purpose, neutrophils adhere at distinct sites in the microvasculature where these immune cells effectively promote thrombosis by shaping the rheological environment for platelet aggregation. In contrast to larger (lower-shear) vessels, this process in high-shear microvessels does not require fibrin generation or extracellular trap formation, but involves GPIbα-vWF and CD40-CD40L-dependent platelet interactions. Conversely, interference with these cellular interactions substantially compromises microvascular clotting. Thus, leukocytes shape the rheological environment in the inflamed venular microvasculature for platelet aggregation thereby effectively promoting the formation of blood clots. Targeting this specific crosstalk between the immune system and the hemostatic system might be instrumental for the prevention and treatment of microvascular thromboembolic pathologies, which are inaccessible to invasive revascularization strategies.
The panniculus carnosus muscle: A novel model of striated muscle regeneration that exhibits sex differences in the mdx mouse
Authors: Bahri Ola A. , Naldaiz-Gastesi Neia , Kennedy Donna C. , Wheatley Antony M. , Izeta Ander , McCullagh Karl J. A. 
Published: November 2019

AbstractThe dermal striated muscle panniculus carnosus (PC), prevalent in lower mammals with remnants in humans, is highly regenerative, and whose function is purported to be linked to defence and shivering thermogenesis. Given the heterogeneity of responses of different muscles to disease, we set out to characterize the PC in wild-type and muscular dystrophic mdx mice. The mouse PC contained mainly fast-twitch type IIB myofibers showing body wide distribution. The PC exemplified heterogeneity in myofiber sizes and a prevalence of central nucleated fibres (CNFs), hallmarks of regeneration, in wild-type and mdx muscles, which increased with age. PC myofibers were hypertrophic in mdx compared to wild-type mice. Sexual dimorphism was apparent with a two-fold increase in CNFs in PC from male versus female mdx mice. To evaluate myogenic potential, PC muscle progenitors were isolated from 8-week old wild-type and mdx mice, grown and differentiated for 7-days. Myogenic profiling of PC-derived myocytes suggested that male mdx satellite cells (SCs) were more myogenic than female counterparts, independent of SC density in PC muscles. Muscle regenerative differences in the PC were associated with alterations in expression of calcium handling regulatory proteins. These studies highlight unique aspects of the PC muscle and its potential as a model to study mechanisms of striated muscle regeneration in health and disease.
Terrestrial Vegetation Drives Methane Production in the Sediments of two German Reservoirs
Authors: Tittel Jörg , Hüls Matthias , Koschorreck Matthias 
Published: November 2019

AbstractInland waters and reservoirs in particular are significant sources of methane to the atmosphere. However, little information is available on the extent to which organic carbon from terrestrial vegetation or from internal photosynthesis fuels the methane production. This limits our ability to constrain methane emissions efficiently. We studied the isotopic composition (13C, 14C) of pelagic and sedimentary carbon sources in two small German reservoirs. The methane was enriched by radiocarbon with isotopic ranges (∆14C 5‰ to 31‰) near to fresh terrestrial organic carbon (OC, 17‰ to 26‰). In contrast, potential source OC produced by internal photosynthesis was characterized by negative ∆14C values (−30‰ and −25‰) as derived from signatures of inorganic carbon in the reservoirs. The particulate OC in stream supplies (terrestrial OC) was also 14C depleted in almost all cases, but highly variable in ∆14C (−131‰ to 42‰). Although the import of terrestrial OC was lower than the amount of OC produced by reservoir-internal photosynthesis, we conclude that the methane production was predominantly fuelled by catchment vegetation. The utilized terrestrial OC was of contemporary origin, fixed within years to decades before sampling and supplemented with reservoir-internal or aged terrestrial OC. Our results indicate that terrestrial biomass is an important driver of methane production in reservoirs receiving significant imports of terrestrial OC.