bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Novel Cooperative Teleoperation Framework for Nonlinear Time-Delayed Single-Master/Multi-Slave System
Authors: Farahmandrad Maryam , Ganjefar Soheil , Talebi Heidar Ali , Bayati Mahdi 
Published: May 2019

SummaryThis paper proposes a novel control framework for a single-master/multi-slave teleoperation system to grasp and handle an object, considering nonlinearity and uncertainty in the dynamics of the slaves and time-varying delay in the communication channel. Based on passive decomposition approach, the dynamics of the slaves are decomposed into two decoupled systems, and then two higher order sliding mode controllers are designed to control them. Also, a synchronization control methodology for the master is developed. Stability is fully studied using the passivity property and Lyapunov theorem. Finally, simulation and practical results confirm that the control system works well against the conditions.
Evaluating the utility of routine screening catheterisation before interstage discharge of infants with single-ventricle physiology
Authors: Bates Katherine E. , Glatz Andrew C. , Giglia Therese M. , Natarajan Shobha S. , Ravishankar Chitra , Stagg Alyson , Rome Jonathan J. 
Published: May 2019

AbstractIntroduction:Interstage mortality causes are often unknown in infants with shunt-dependent univentricular defects. For 2 years, screening catheterisation was encouraged before neonatal discharge to determine if routine evaluation improved interstage outcomes.Methods:Retrospective single-centre review of home monitoring programme from December, 2010 to June, 2012. Composite scores were created for physical examination/echocardiography risk factors; catheterisation risk factors; and interstage adverse events. Composite scores were compared between usual care and screening catheterisation groups. The ability of each risk factor composite to predict interstage adverse events, individually and in combination, was assessed with sensitivity, specificity, and receiver operating characteristic curves.Results:There were 27 usual care and 32 screening catheterisation patients. There were no significant differences between groups except rates of catheterisation before discharge (29.6 versus 100%, p < 0.001). Usual care patients who underwent catheterisation for clinical indications had higher intervention rates (37.5 versus 3.1%, p = 0.004). Physical examination/echocardiography risk factor frequency was similar, but usual care patients with catheterisation had a higher catheterisation risk factor frequency. Interstage adverse event frequency was similar (48.2 versus 53.1%, p = 0.7). For interstage adverse event prediction, sensitivity for the physical examination/echocardiography, catheterisation, and either risk factor composites was 53.3, 72, and 80%, respectively; specificity was 59, 60, and 48%. The area under the receiver operating characteristic curve was 0.56, 0.66, and 0.64.Conclusion:Screening catheterisation evaluation offered slightly increased sensitivity and specificity, but no difference in interstage adverse event frequency. Given this small advantage versus known risks, screening catheterisations are no longer encouraged.
Bailout or bust? Government evaluations in the wake of a bailout
Authors: Larsen Erik Gahner , Klemmensen Robert , Klitgaard Michael Baggesen 
Published: May 2019

AbstractGovernments are often punished for negative events such as economic downturns and financial shocks. However, governments can address such shocks with salient policy responses that might mitigate public punishment. We use three high-quality nationally representative surveys collected around a key event in the history of the Dutch economy, namely the outbreak of the financial crisis in 2008, to examine how voters responded to a salient government bailout. The results illustrate that governments can get substantial credit for pursuing a bailout in the midst of a financial crisis. Future research should take salient policy responses into account to fully understand the public response to the outbreak of financial and economic crises.
Broadband dual linear polarized (DLP) antenna array for energy harvesting system
Authors: Elsheakh Dalia N. 
Published: May 2019

AbstractA broadband linear polarized antenna is designed for radio frequency energy harvesting. The antenna covers the frequency range from 1 up to 6 GHz with relative impedance bandwidth of 126% at −6 dB reflection coefficient |S11| and extended from 1.1 to 3.3 GHz and from 4.2 to 5.6 GHz at |S11| ≤ −10 dB. A 2 × 2 dual linear polarized (DLP) antenna array is designed based on the antenna element by using equal phase and equal power divider 1-to-4 Wilkinson power divider with 180° phase shifter. The DLP antenna array covers the frequency band from 1.8 to 2.9 GHz. This frequency band covers a wide range of modern wireless communication standards, including GSM 1800, UMTS 2100, Wi-Fi 2.4, and most of LTE bands. The developed array prototype was then used to experimentally validate the simulation results. The horizontally and vertically polarized gain of the designed array were found to be quite similar across the 1.8–2.9 frequency band with an average gain value of 5.5 dBi.
Characteristics of Surface Meteorology at Lindsey Islands, Amundsen Sea, West Antarctica
Authors: Choi Taej in , Kim Seong‐Joong , Kim Ji Hee , Kwon Hataek , Lazzara Matthew A. 
Published: May 2019

AbstractInvestigating warming in West Antarctica is important to understand and predict mass balance changes of the ice sheet. However, clear understanding of the extent and rate of warming across West Antarctica has been limited by the lack of ground‐based meteorological measurements. An automatic weather station was set up at Lindsey Islands, the Amundsen Sea of West Antarctica, in 2008, and operated for about 7 years. The measured variables showed high interannual variability, particularly in winter seasons. The longitudinal shift of the center of the Amundsen Sea Low contributed to the large variability and resulted in much lower temperatures at the site, especially in winter seasons, through cold advection from the south. The measured data showed good agreement with ERA‐Interim and ERA5 reanalysis data, though there was a large negative bias in wind speed. The ERA‐Interim reanalysis data showed no significant trends in seasonal averaged temperature from 1980 to 2014, but significant trends were shown in pressure and wind speed in autumn (p < 0.05), even though the interpretation of the trend requires caution. The seasonal correlation coefficients of monthly averaged temperature (T) and pressure (P) between the study site and three neighboring automatic weather station sites in the coastal area were >0.8 for T and >0.92 for P and up to 0.76 for P and 0.72 for T at an inland site.
East Asian Monsoon as a Modulator of U.S. Great Plains Heat Waves
Authors: Lopez Hosmay , Lee Sang‐Ki , Dong Shenfu , Goni Gustavo , Kirtman Ben , Atlas Robert , Kumar Arun 
Published: May 2019

AbstractHeat waves are the leading weather‐related cause of death in the United States, with the most recent examples occurring in the summers of 2011 and 2012 over the Great Plains. These events are unusual and largely unpredictable beyond the synoptic timescale. Their number and severity have increased and are projected to continue to increase, prompting the need to identify the physical processes that modulate heat waves and, consequently, can lead to improved prediction and future projection. Our results based on observations and model simulations suggest that convective latent heat release from the East Asian Monsoon enhances the likelihood of droughts and heat waves over the United States through an equivalent barotropic wave train along the subtropical jet stream, promoting an anticyclonic circulation pattern over the Great Plains. This anticyclone serves as a blocking pattern for transient synoptic‐scale systems and is supportive of persistent drought and clear sky conditions, promoting high temperatures and heat waves.
Sustained Nonphotochemical Quenching Shapes the Seasonal Pattern of Solar‐Induced Fluorescence at a High‐Elevation Evergreen Forest
Authors: Raczka Brett , Porcar‐Castell A. , Magney T. , Lee J. E. , Köhler P. , Frankenberg C. , Grossmann K. , Logan B. A. , Stutz J. , Blanken P. D. , Burns S. P. , Duarte H. , Yang X. , Lin J. C. , Bowling D. R. 
Published: May 2019

AbstractTraditional methods of carbon monitoring in mountainous regions are challenged by complex terrain. Recently, solar‐induced fluorescence (SIF) has been found to be an indicator of gross primary production (GPP), and the increased availability of remotely sensed SIF provides an opportunity to estimate GPP across the Western United States. Although the empirical linkage between SIF and GPP is strong, the current mechanistic understanding of this linkage is incomplete and depends upon changes in leaf biochemical processes in which absorbed sunlight leads to photochemistry, heat (via nonphotochemical quenching [NPQ]), fluorescence, or tissue damage. An improved mechanistic understanding is necessary to leverage SIF observations to improve representation of ecosystem processes within land surface models. Here we included an improved fluorescence model within the Community Land Model, Version 4.5 (CLM 4.5), to simulate seasonal changes in SIF at a subalpine forest in Colorado. We found that when the model accounted for sustained NPQ, this provided a larger seasonal change in fluorescence yield leading to simulated SIF that more closely resembled the observed seasonal pattern (Global Ozone Monitoring Experiment‐2 [GOME‐2] satellite platform and a tower‐mounted spectrometer system). We found that an acclimation model based on mean air temperature was a useful predictor for sustained NPQ. Although light intensity was not an important factor for this analysis, it should be considered before applying the sustained NPQ and SIF to other cold climate evergreen biomes. More leaf‐level fluorescence measurements are necessary to better understand the seasonal relationship between sustained and reversible components of NPQ and to what extent that influences SIF.
Magnetism Signals in a Stalagmite From Southern China and Reconstruction of Paleorainfall During the Interglacial‐Glacial Transition
Authors: Chen Q. , Zhang T. W. , Wang Y. T. , Zhao J. X. , Feng Y. X. , Liao W. , Wang W. , Yang X. Q. 
Published: May 2019

AbstractPrecipitation variations deduced from speleothem stable oxygen isotopes (δ18O) have long been debated in monsoonal China. The magnetic property in speleothems is interpreted to be related to regional precipitation and can therefore offer reliable information of regional precipitation variations. Here we present a speleothem from southern China to explore the magnetic signals in speleothems and to reconstruct regional precipitation in hominin‐occupational area in southern China during MIS5. Saturation magnetization (Ms), which represents the magnetic mineral concentrations, is used as an indicator of effective rainfall variations. The precipitation inferred from Ms increased sharply in the period prior to 80.3 ka before present, followed by a drop to precipitation anomaly afterward, indicating that regional precipitation varied greatly during the hominin‐occupied interval in southern China. Power spectrum analysis of Ms values shows significant ~205‐, ~90‐, ~77‐, and ~64‐year periodicities, suggesting that the solar activity may play an important role in precipitation variations in southern China during the MIS5a/4 transition.
Reconstruction of Cloud Vertical Structure With a Generative Adversarial Network
Authors: Leinonen Jussi , Guillaume Alexandre , Yuan Tianle 
Published: May 2019

AbstractWe demonstrate the feasibility of solving atmospheric remote sensing problems with machine learning using conditional generative adversarial networks (CGANs), implemented using convolutional neural networks. We apply the CGAN to generating two‐dimensional cloud vertical structures that would be observed by the CloudSat satellite‐based radar, using only the collocated Moderate‐Resolution Imaging Spectrometer measurements as input. The CGAN is usually able to generate reasonable guesses of the cloud structure and can infer complex structures such as multilayer clouds from the Moderate‐Resolution Imaging Spectrometer data. This network, which is formulated probabilistically, also estimates the uncertainty of its own predictions. We examine the statistics of the generated data and analyze the response of the network to each input parameter. The success of the CGAN in solving this problem suggests that generative adversarial networks are applicable to a wide range of problems in atmospheric science, a field characterized by complex spatial structures and observational uncertainties.
Quantifying Wind Erosion During the Late Quaternary in the Qaidam Basin, Central Asia
Authors: Wu Lei , Prush Veronica , Lin Xiubin , Xiao Ancheng , Zhang Li , Chen Ninghua , Yang Rong , Chen Hanlin 
Published: May 2019

AbstractWind erosion is an important surface process on terrestrial planets but is difficult to quantify particularly on long‐term timescales. Here we use high‐resolution Terrestrial Laser Scanning and cosmogenic Beryllium‐10 (10Be) exposure dating to investigate the yardangs, a wind‐eroded landform with aerodynamic forms, within the western Qaidam Basin, Central Asia. The results indicate that the yardangs started to form at ~105 ka, coincident with the early phase of the arid last glacial period. We further calibrated the wind erosion rate in the last glacial period to be ~0.26 mm/a, twice as fast as that of the present‐day interglacial period in our study site. Our results highlight the severe wind erosion during glacial periods and emphasize the fundamental control of global glacial‐interglacial climate oscillations on the secular variation in wind erosion in the Qaidam Basin during the late Quaternary period.
Evolution of an Upward Negative Lightning Flash Triggered by a Distant +CG From a 257‐m‐Tall Tower, Including Initiation of Subsequent Strokes
Authors: Zhu Y. , Ding Z. , Rakov V. A. , Tran M. D. 
Published: May 2019

AbstractUsing the high‐speed optical and electric field records, in conjunction with Earth Networks Total Lightning Network and radar data, we examined in detail the morphology and evolution of an upward negative flash containing six downward leader/upward return stroke sequences terminated on a 257‐m tower in Florida. The upward flash was induced (triggered) by a single‐stroke 50‐kA +CG that occurred about 45 km from the tower. The in‐cloud part of +CG was optically detected to extend toward the tower and appeared to stop at a height of about 3 km above the tower top. The six leader‐return‐stroke sequences were each initiated by a bidirectional leader utilizing the remnants of branches created during the initial stage. Electric field signatures of bidirectional leaders were similar to K‐changes. The upper end of the return‐stroke channel in all six cases exhibited branching and appeared to extend to higher altitudes or/and move closer to Lightning Observatory in Gainesville with increasing stroke order.
Time Scales for Electron Quasi‐linear Diffusion by Lower‐Band Chorus Waves: The Effects of ωpe/Ωce Dependence on Geomagnetic Activity
Authors: Agapitov O. , Mourenas D. , Artemyev A. , Hospodarsky G. , Bonnell J.W. 
Published: May 2019

AbstractElectron scattering by chorus waves is an important mechanism that can lead to fast electron acceleration and loss in the outer radiation belt. Making use of Van Allen Probes measurements, we present the first statistical survey of megaelectron volt electron pitch angle and energy quasi‐linear diffusion rates by chorus waves as a function of L‐shell, local time, and AE index, taking into account the local electron plasma frequency to gyrofrequency ratio ωpe/Ωce, chorus wave frequency, and resonance wave amplitude. We demonstrate that during disturbed periods, ωpe/Ωce strongly decreases in the night sector, leading to a faster electron loss but also a much faster electron energization in two distinct regions just above the plasmapause and at L ~ 3.5–5.5. Spatiotemporal variations of ωpe/Ωce with AE shape the evolution of electron energization in the outer belt, sometimes leading to very short time scales for quasi‐linear megaelectron volt electron acceleration in agreement with Van Allen Probes observations.
Individual variability in behavior and functional networks predicts vulnerability using an animal model of PTSD
Authors: Dopfel David , Perez Pablo D. , Verbitsky Alexander , Bravo-Rivera Hector , Ma Yuncong , Quirk Gregory J. , Zhang Nanyin 
Published: May 2019

AbstractOnly a minority of individuals experiencing trauma subsequently develop post-traumatic stress disorder (PTSD). However, whether differences in vulnerability to PTSD result from a predisposition or trauma exposure remains unclear. A major challenge in differentiating these possibilities is that clinical studies focus on individuals already exposed to trauma without pre-trauma conditions. Here, using the predator scent model of PTSD in rats and a longitudinal design, we measure pre-trauma brain-wide neural circuit functional connectivity, behavioral and corticosterone responses to trauma exposure, and post-trauma anxiety. Freezing during predator scent exposure correlates with functional connectivity in a set of neural circuits, indicating pre-existing circuit function can predispose animals to differential fearful responses to threats. Counterintuitively, rats with lower freezing show more avoidance of the predator scent, a prolonged corticosterone response, and higher anxiety long after exposure. This study provides a framework of pre-existing circuit function that determines threat responses, which might directly relate to PTSD-like behaviors.
Flexible and scalable diagnostic filtering of genomic variants using G2P with Ensembl VEP
Authors: Thormann Anja , Halachev Mihail , McLaren William , Moore David J. , Svinti Victoria , Campbell Archie , Kerr Shona M. , Tischkowitz Marc , Hunt Sarah E. , Dunlop Malcolm G. , Hurles Matthew E. , Wright Caroline F. , Firth Helen V. , Cunningham Fiona , FitzPatrick David R. 
Published: May 2019

AbstractWe aimed to develop an efficient, flexible and scalable approach to diagnostic genome-wide sequence analysis of genetically heterogeneous clinical presentations. Here we present G2P (www.ebi.ac.uk/gene2phenotype) as an online system to establish, curate and distribute datasets for diagnostic variant filtering via association of allelic requirement and mutational consequence at a defined locus with phenotypic terms, confidence level and evidence links. An extension to Ensembl Variant Effect Predictor (VEP), VEP-G2P was used to filter both disease-associated and control whole exome sequence (WES) with Developmental Disorders G2P (G2PDD; 2044 entries). VEP-G2PDD shows a sensitivity/precision of 97.3%/33% for de novo and 81.6%/22.7% for inherited pathogenic genotypes respectively. Many of the missing genotypes are likely false-positive pathogenic assignments. The expected number and discriminative features of background genotypes are defined using control WES. Using only human genetic data VEP-G2P performs well compared to other freely-available diagnostic systems and future phenotypic matching capabilities should further enhance performance.
A unified relationship for evaporation kinetics at low Mach numbers
Authors: Lu Zhengmao , Kinefuchi Ikuya , Wilke Kyle L. , Vaartstra Geoffrey , Wang Evelyn N. 
Published: May 2019

AbstractWe experimentally realized and elucidated kinetically limited evaporation where the molecular gas dynamics close to the liquid–vapour interface dominates the overall transport. This process fundamentally dictates the performance of various evaporative systems and has received significant theoretical interest. However, experimental studies have been limited due to the difficulty of isolating the interfacial thermal resistance. Here, we overcome this challenge using an ultrathin nanoporous membrane in a pure vapour ambient. We demonstrate a fundamental relationship between the evaporation flux and driving potential in a dimensionless form, which unifies kinetically limited evaporation under different working conditions. We model the nonequilibrium gas kinetics and show good agreement between experiments and theory. Our work provides a general figure of merit for evaporative heat transfer as well as design guidelines for achieving efficient evaporation in applications such as water purification, steam generation, and thermal management.
Sensory perception of dead conspecifics induces aversive cues and modulates lifespan through serotonin in Drosophila
Authors: Chakraborty Tuhin S. , Gendron Christi M. , Lyu Yang , Munneke Allyson S. , DeMarco Madeline N. , Hoisington Zachary W. , Pletcher Scott D. 
Published: May 2019

AbstractSensory perception modulates health and aging across taxa. Understanding the nature of relevant cues and the mechanisms underlying their action may lead to novel interventions that improve the length and quality of life. We found that in the vinegar fly, Drosophila melanogaster, exposure to dead conspecifics in the environment induced cues that were aversive to other flies, modulated physiology, and impaired longevity. The effects of exposure to dead conspecifics on aversiveness and lifespan required visual and olfactory function in the exposed flies. Furthermore, the sight of dead flies was sufficient to produce aversive cues and to induce changes in the head metabolome. Genetic and pharmacologic attenuation of serotonergic signaling eliminated the effects of exposure on aversiveness and lifespan. Our results indicate that Drosophila have an ability to perceive dead conspecifics in their environment and suggest conserved mechanistic links between neural state, health, and aging; the roots of which might be unearthed using invertebrate model systems.
Atomic-scale combination of germanium-zinc nanofibers for structural and electrochemical evolution
Authors: Song Gyujin , Cheong Jun Young , Kim Chanhoon , Luo Langli , Hwang Chihyun , Choi Sungho , Ryu Jaegeon , Kim Sungho , Song Woo-Jin , Song Hyun-Kon , Wang Chongmin , Kim Il-Doo , Park Soojin 
Published: May 2019

AbstractAlloys are recently receiving considerable attention in the community of rechargeable batteries as possible alternatives to carbonaceous negative electrodes; however, challenges remain for the practical utilization of these materials. Herein, we report the synthesis of germanium-zinc alloy nanofibers through electrospinning and a subsequent calcination step. Evidenced by in situ transmission electron microscopy and electrochemical impedance spectroscopy characterizations, this one-dimensional design possesses unique structures. Both germanium and zinc atoms are homogenously distributed allowing for outstanding electronic conductivity and high available capacity for lithium storage. The as-prepared materials present high rate capability (capacity of ~ 50% at 20 C compared to that at 0.2 C-rate) and cycle retention (73% at 3.0 C-rate) with a retaining capacity of 546 mAh g−1 even after 1000 cycles. When assembled in a full cell, high energy density can be maintained during 400 cycles, which indicates that the current material has the potential to be used in a large-scale energy storage system.