bluuebunny/crossref_metadata_2025_split huggingface dataset:
Asymmetric hybridization in Cordulegaster (Odonata: Cordulegastridae): Secondary postglacial contact and the possible role of mechanical constraints
Authors: Solano Emanuela , Hardersen Sönke , Audisio Paolo , Amorosi Valentina , Senczuk Gabriele , Antonini Gloria 
Published: September 2018

AbstractTwo Cordulegaster dragonflies present in Italy, the Palaearctic and northern distributed Cordulegaster boltonii and the endemic to the south of the peninsula Cordulegaster trinacriae, meet in central Italy and give rise to individuals of intermediate morphology. By means of mitochondrial and nuclear markers and of Geometric Morphometrics applied to sexual appendages, we defined i) the geographical boundaries between the two species in Italy and ii) we determined the presence, the extent, and the genetic characteristics of the hybridization. Genetic data evidenced asymmetric hybridization with the males of C. trinacriae able to mate both interspecifically and intraspecifically. The results contrast with expectations under neutral gene introgression and sexual selection. This data, along with the morphological evidence of significant differences in size and shape of sexual appendages between the males of the two species, seem indicative of the role of mechanical constraints in intraspecific matings. The origin of the two species is dated about to 1.32 Mya and the hybridization resulted related to range expansion of the two species after Last Glacial Maximum and this led to the secondary contact between the two taxa in central Italy. At last, our results indicate that the range of C. trinacriae, a threatened and protected species, has been moving northward probably driven by climate changes. As a result, the latter species is currently intruding into the range of C. boltonii. The hybrid area is quite extended and the hybrids seem well adapted to the environment. From a conservation point of view, even if C. trinacriae has a strong genetic identity, the discovery of hybridization between the two species should be considered in a future species management.
In situ measurements of fine sediment infiltration (FSI) in gravel‐bed rivers with a hydropeaking flow regime
Authors: Hauer Christoph , Holzapfel Patrick , Tonolla Diego , Habersack Helmut , Zolezzi Guido 
Published: September 2018

AbstractThe overpresence of fine sediment and fine sediment infiltration (FSI) in the aquatic environment of rivers are of increasing importance due to their limiting effects on habitat quality and use. The habitats of both macroinvertebrates and fish, especially spawning sites, can be negatively affected. More recently, hydropeaking has been mentioned as a driving factor in fine sediment dynamics and FSI in gravel‐bed rivers. The primary aim of the present study was to quantify FSI in the vertical stratigraphy of alpine rivers with hydropeaking flow regimes in order to identify possible differences in FSI between the permanently wetted area (during base and peak flows) and the so‐called dewatering areas, which are only inundated during peak flows. Moreover, we assessed whether the discharge ratio between base and peak flow is able to explain the magnitude of FSI. To address these aims, freeze‐core samples were taken in eight different alpine river catchments. The results showed significant differences in the vertical stratification of FSI between the permanently wetted area during base flow and the dewatering sites. Surface clogging occurred only in the dewatering areas, with decreasing percentages of fine sediments associated with increasing core depths. In contrast, permanently wetted areas contained little or no fine sediment concentrations on the surface of the river bed. Furthermore, no statistical relationship was observed between the magnitude of hydropeaking and the sampled FSI rate. A repeated survey of FSI in the gravel matrix revealed the importance of de‐clogging caused by flooding and the importance of FSI in the aquatic environment, especially in the initial stages of riparian vegetation establishment. © 2018 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd.
Irrigation Strategies for Rotational Grazing Pasture in Canterbury, New Zealand, and Impacts on Irrigation Efficiency
Authors: KC Birendra , Mohssen Magdy , Chau Henry , Curtis Andrew , Cuenca Richard , Bright John , Srinivasan Ms , Safa Majeed 
Published: September 2018

AbstractTo support irrigation efficiency improvement, it is essential to identify the major limitations to irrigation management. Thirty‐two dairy farmers in Canterbury, New Zealand, were interviewed in order to understand current irrigation strategies on pastoral farms, particularly in relation to grazing rotations and plant available water (PAW). A water balance model, IrriCalc, was used to estimate irrigation and drainage from irrigation strategies obtained from the survey.Current irrigation strategies differ greatly from farm to farm, which depend solely on PAW with no consideration for grazing rotations. During shoulder seasons (Sept–Oct and Mar–Apr) the majority of farmers start irrigation at 50% PAW and stop at 80% PAW. During the peak irrigation season (Nov–Feb) irrigation mostly starts at 70% PAW and stops at 100% PAW, leaving no room for precipitation. Results showed that over 14 irrigation seasons (2001/2002–2014/2015) this irrigation strategy would have produced a range of drainage per irrigation season between 40 and 400 mm, which demonstrates a high potential of optimising current irrigation strategies. Better utilization of rainfall during the irrigation season would minimize irrigation requirements and drainage losses. This would help to address the issues of nutrient losses and relieve the pressure on water resources. © 2018 John Wiley & Sons, Ltd.
Repeatability of Dixon magnetic resonance imaging and magnetic resonance spectroscopy for quantitative muscle fat assessments in the thigh
Authors: Grimm Alexandra , Meyer Heiko , Nickel Marcel D. , Nittka Mathias , Raithel Esther , Chaudry Oliver , Friedberger Andreas , Uder Michael , Kemmler Wolfgang , Engelke Klaus , Quick Harald H. 
Published: September 2018

AbstractBackgroundChanges in muscle fat composition as for example observed in sarcopenia or muscular dystrophy affect physical performance and muscular function, like strength and power. The purpose of the present study is to measure the repeatability of Dixon magnetic resonance imaging (MRI) for assessing muscle volume and fat in the thigh. Furthermore, repeatability of magnetic resonance spectroscopy (MRS) for assessing muscle fat is determined.MethodsA prototype 6‐point Dixon MRI method was used to measure muscle volume and muscle proton density fat fraction (PDFF) in the left thigh. PDFF was measured in musculus semitendinosus of the left thigh with a T2‐corrected multi‐echo MRS method. For the determination of short‐term repeatability (consecutive examinations), the root mean square coefficients of variation of Dixon MRI and MRS data of 23 young and healthy (29 ± 5 years) and 24 elderly men with sarcopenia (78 ± 5 years) were calculated. For the estimation of the long‐term repeatability (13 weeks between examinations), the root mean square coefficients of variation of MRI data of seven young and healthy (31 ± 7 years) and 23 elderly sarcopenic men (76 ± 5 years) were calculated. Long‐term repeatability of MRS was not determined.ResultsShort‐term errors of Dixon MRI volume measurement were between 1.2% and 1.5%, between 2.1% and 1.6% for Dixon MRI PDFF measurement, and between 9.0% and 15.3% for MRS. Because of the high short‐term repeatability errors of MRS, long‐term errors were not determined. Long‐term errors of MRI volume measurement were between 1.9% and 4.0% and of Dixon MRI PDFF measurement between 2.1% and 4.2%.ConclusionsThe high degree of repeatability of volume and PDFF Dixon MRI supports its use to predict future mobility impairment and measures the success of therapeutic interventions, for example, in sarcopenia in aging populations and muscular dystrophy. Because of possible inhomogeneity of fat infiltration in muscle tissue, the application of MRS for PDFF measurements in muscle is more problematic because this may result in high repeatability errors. In addition, the tissue composition within the MRS voxel may not be representative for the whole muscle.
Automatic and multithreaded method for determining the number of vector fitting poles based on empirical data
Authors: Al‐Hawari Feras H. 
Published: September 2018

AbstractThe vector fitting method has been largely used to generate accurate and passive time‐domain macromodels for circuits or structures characterized by frequency‐domain data such as scattering parameters. Nevertheless, very few approaches to determine the vector fitting order were discussed in the literature. In this paper, an iterative method to automatically identify the number of vector fitting poles is proposed. It can achieve acceptable performance and accuracy by capitalizing on the fact that the number of vector fitting poles lies in the range that spans the number of resonance peaks in the model and double that number as deduced from the empirical data that was acquired by experimentation on different types of models. Therefore, the algorithm's awareness of the frequency response of the model and confining the search for an acceptable order within the aforementioned range proved to be key factors to enable it to mostly outperform its MATLAB counterpart as shown in the experimental results. Furthermore, a multithreaded implementation of the proposed method is introduced to distribute the vector fitting passes on multicore processors in order to obtain a better speedup factor. The experiments that demonstrate the positive effect of the multithreaded version on performance are also presented.
Immunomodulators targeting the PD‐1/PD‐L1 protein‐protein interaction: From antibodies to small molecules
Authors: Yang Jeffrey , Hu Longqin 
Published: September 2018

AbstractCancer immunotherapy has made great strides in the recent decade, especially in the area of immune checkpoint blockade. The outstanding efficacy, prolonged durability of effect, and rapid assimilation of anti‐PD‐1 and anti‐PD‐L1 monoclonal antibodies in clinical practice have been nothing short of a medical breakthrough in the treatment of numerous malignancies. The major advantages of these therapeutic antibodies over their small molecule counterparts have been their high binding affinity and target specificity. However, antibodies do have their flaws including immune‐related toxicities, inadequate pharmacokinetics and tumor penetration, and high cost burden to manufacturers and consumers. These limitations hinder broader clinical applications of the antibodies and have heightened interests in developing the alternative small molecule platform that includes peptidomimetics and peptides to target the PD‐1/PD‐L1 immune checkpoint system. The progress on these small molecule alternatives has been relatively slow compared to that of the antibodies. Fortunately, recent structural studies of the interactions among PD‐1, PD‐L1, and their respective antibodies have revealed key hotspots on PD‐1 and PD‐L1 that may facilitate drug discovery efforts for small molecule immunotherapeutics. This review is intended to discuss key concepts in immuno‐oncology, describe the successes and shortcomings of PD‐1/PD‐L1 antibody‐based therapies, and to highlight the recent development of small molecule inhibitors of the PD‐1/PD‐L1 protein‐protein interaction.
A Bayesian multivariate approach to estimating the prevalence of a superordinate category of disorders
Authors: Fawcett Jonathan M. , Fairbrother Nichole , Fawcett Emily J. , White Ian R. 
Published: September 2018

AbstractObjectiveEpidemiological research plays an important role in public health, facilitated by the meta‐analytic aggregation of epidemiological trials into a single, more powerful estimate. This form of aggregation is complicated when estimating the prevalence of a superordinate category of disorders (e.g., “any anxiety disorder,” “any cardiac disorder”) because epidemiological studies rarely include all of the disorders selected to define the superordinate category. In this paper, we suggest that estimating the prevalence of a superordinate category based on studies with differing operationalization of that category (in the form of different disorders measured) is both common and ill‐advised. Our objective is to provide a better approach.MethodsWe propose a multivariate method using individual disorder prevalences to produce a fully Bayesian estimate of the probability of having one or more of those disorders. We validate this approach using a recent case study and parameter recovery simulations.ResultsOur approach produced less biased and more reliable estimates than other common approaches, which were at times highly biased.ConclusionAlthough our approach entails additional effort (e.g., contacting authors for individual participant data), the improved accuracy of the prevalence estimates obtained is significant and therefore recommended.
Output feedback stabilization for a cascaded heat PDE‐ODE system subject to uncertain disturbance
Authors: Jia Yan‐Na , Liu Jun‐Jun , Li Sheng‐Jia 
Published: September 2018

SummaryIn this paper, we are concerned with the output feedback exponential stabilization of a cascaded parabolic partial differential equation–ordinary differential equation system where the control end suffers from the external uncertain disturbance. We design an unknown input–type state observer with the disturbance estimator term, which is used to stabilize this cascaded system and compensate the external disturbance simultaneously. The stabilizing state feedback control is designed for the observer system by the three‐step backstepping transformation, which is the corresponding observer‐based output feedback stabilizing control for the original system. Finally, the closed‐loop system is shown to be exponentially stable.
Unknown inputs observer design for descriptor systems with monotone nonlinearities
Authors: Gupta Mahendra Kumar , Tomar Nutan Kumar , Darouach Mohamed 
Published: September 2018

SummaryThis paper is devoted to the reduced‐order unknown inputs observer design problem for a class of descriptor systems having generalized monotone nonlinearities. The underlying system is considered in general rectangular form with unknown inputs in dynamic and in output equations. Under some basic assumptions on system parameters, sufficient conditions for the existence of observers are proved by showing the stability of their error dynamics. The case where nonlinearity appears in output equation is also considered. The importance of the work is illustrated by real‐life and academic examples.
System dynamics at sixty: the path forward
Authors: Sterman John 
Published: September 2018

AbstractThe late Jay Forrester founded the field of system dynamics 60 years ago. On this anniversary I ask what lessons his remarkable life of innovation and impact hold for the field. From a Nebraska ranch to MIT, servomechanisms, digital computing and system dynamics, Jay lived his entire life on the frontier, innovating to solve critical problems. Today, more than ever, humanity faces grave threats arising from our mismanagement of increasingly complex systems. Fortunately, progress in system dynamics, the natural and social sciences, computing, data availability, and other modeling disciplines have advanced the frontier in theory and methods to build reliable, useful knowledge of complex systems. We must therefore ask: What would Jay do if he were young today? How would he build on the knowledge, technology, data and methods now available to improve the science and practice of system dynamics? What must we now do to explore the next frontier?© 2018 System Dynamics Society
A diachronic perspective on peer disagreement in veritistic social epistemology
Authors: Olsson Erik J. 
Published: September 2018

Abstract
The main issue in the epistemology of peer disagreement is whether known disagreement among those who are in symmetrical epistemic positions undermines the rationality of their maintaining their respective views. Douven and Kelp have argued convincingly that this problem is best understood as being about how to respond to peer disagreement repeatedly over time, and that this diachronic issue can be best approached through computer simulation. However, Douven and Kelp’s favored simulation framework cannot naturally handle Christensen’s famous Mental Math example. As a remedy, I introduce an alternative (Bayesian) simulation framework, Laputa, inspired by Alvin Goldman’s seminal work on veritistic social epistemology. I show that Christensen’s conciliatory response, reasonably reconstructed and supplemented, gives rise to an increase in epistemic (veritistic) value only if the peers continue to recheck their mental math; else the peers might as well be steadfast. On a meta-level, the study illustrates the power of Goldman’s approach when combined with simulation techniques for handling the computational issues involved.
VSP polarization angles determination: Wysin-1 processing case study
Authors: Zaręba Mateusz , Danek Tomasz 
Published: September 2018

Abstract
In this paper, we present an analysis of borehole seismic data processing procedures required to obtain high-quality vertical stacks and polarization angles in the case of walkaway VSP (vertical seismic profile) data gathered in challenging conditions. As polarization angles are necessary for more advanced procedures like anisotropy parameters determination, their quality is critical for proper media description. Examined Wysin-1 VSP experiment data indicated that the best results can be obtained when rotation is performed for each shot on data after de-noising and vertical stacking of un-rotated data. Additionally, we proposed a procedure of signal matching that can substantially increase data quality.
Proglacial damlakes in eastern Transbaikalia: New insight into the Pleistocene paleogeography
Authors: Enikeev F.I. 
Published: September 2018

Abstract
Paleogeographic reconstructions for the Samarovo, Taz, Murukta, and Sartan glaciations reveal the formation conditions of proglacial lakes dammed by ice in intermontane depressions and valleys of large rivers in eastern Transbaikalia. Middle–Late Pleistocene climate change is reconstructed using spore–pollen spectra from Pleistocene sediments in northern Transbaikalia. The age and lifetime of proglacial lakes are constrained by radiocarbon, thermoluminescence, and varve chronology of their bottom sediments in the periglacial zone. The lake levels remain recorded in sediments produced by deposition and erosion along the former lake shores, as well as in morphology and lithology variations of terminal moraines. A large proglacial lake, with a maximum level of 1020 m, occupied vast areas in Transbaikalia and its surroundings during the Samarovo glaciation. After the glaciers degraded, the Amur River system expanded into the area of closed lake basins in the southeastern Baikal region, including North China and Mongolia. The obtained results have implications for the Middle–Late Pleistocene history of lake deposition.
Mathematical and physical modeling to justify a new geophysical method—electrical anisotropy logging
Authors: Karinskiy A.D. , Krasnosel’skikh A.A. 
Published: September 2018

Abstract
Results of theoretical and experimental studies obtained for an electromagnetic logging probe of new design are presented. As in the case of an induction logging probe, the magnetic dipole of the new probe produces a harmonically varying electromagnetic field, and the parameter to be measured is the electric voltage in the short receiving MN line. The theoretical studies have shown that under certain conditions, the results of measurement with this probe depend on the electrical anisotropy coefficient and do not depend on the longitudinal and transverse electrical resistivities of the anisotropic medium. A technique for determining the electrical anisotropy coefficient was tested on experimental data obtained by physical modeling.
Marangoni-enhanced capillary wetting in surfactant-driven superspreading
Authors: Wei Hsien-Hung 
Published: September 2018

Superspreading is a phenomenon such that a drop of a certain class of surfactant on a substrate can spread with a radius that grows linearly with time much faster than the usual capillary wetting. Its origin, in spite of many efforts, is still not fully understood. Previous modelling and simulation studies (Karapetsas et al. J. Fluid Mech., vol. 670, 2011, pp. 5–37; Theodorakis et al. Langmuir, vol. 31, 2015, pp. 2304–2309) suggest that the transfer of the interfacial surfactant molecules onto the substrate in the vicinity of the contact line plays a crucial role in superspreading. Here, we construct a detailed theory to elaborate on this idea, showing that a rational account for superspreading can be made using a purely hydrodynamic approach without involving a specific surfactant structure or sorption kinetics. Using this theory it can be shown analytically, for both insoluble and soluble surfactants, that the curious linear spreading law can be derived from a new dynamic contact line structure due to a tiny surfactant leakage from the air–liquid interface to the substrate. Such a leak not only establishes a concentrated Marangoni shearing toward the contact line at a rate much faster than the usual viscous stress singularity, but also results in a microscopic surfactant-devoid zone in the vicinity of the contact line. The strong Marangoni shearing then turns into a local capillary force in the zone, making the contact line in effect advance in a surfactant-free manner. This local Marangoni-driven capillary wetting in turn renders a constant wetting speed governed by the de Gennes–Cox–Voinov law and hence the linear spreading law. We also determine the range of surfactant concentration within which superspreading can be sustained by local surfactant leakage without being mitigated by the contact line sweeping, explaining why only limited classes of surfactants can serve as superspreaders. We further show that spreading of surfactant spreaders can exhibit either the
$1/6$
or
$1/2$
power law, depending on the ability of interfacial surfactant to transfer/leak to the bulk/substrate. All these findings can account for a variety of results seen in experiments (Rafai et al. Langmuir, vol. 18, 2002, pp. 10486–10488; Nikolov &amp; Wasan, Adv. Colloid Interface Sci., vol. 222, 2015, pp. 517–529) and simulations (Karapetsas et al. 2011). Analogy to thermocapillary spreading is also made, reverberating the ubiquitous role of the Marangoni effect in enhancing dynamic wetting driven by non-uniform surface tension.