bluuebunny/crossref_metadata_2025_split huggingface dataset:
A global dataset of river network geometry
Authors: Giachetta Emanuele , Willett Sean D. 
Published: July 2018

AbstractThe plan-form structure of the world’s river basins contains extensive information regarding tectonic, paleo-geographic and paleo-climate conditions, but interpretation of this structure is complicated by the need to disentangle these processes from the autogenic behavior of fluvial processes. One method of interpreting this structure is by integrating channel length and drainage area as characterized by the scaling relationship between slope and area, resulting in a characteristic length parameter, referred to in recent studies as χ. In this paper, we apply this methodology at a continental scale by calculating χ for the world’s river networks. Mapping of χ', a modified version of χ including the influence of precipitation distribution on river discharge and correction of base level for χ' in closed basins, illustrates the geometric structure of global river networks, thus highlighting where tectonics or changing climate have resulted in an apparent disequilibrium of the river channel geometry. Our global χ maps quantify a dynamic view of Earth’s river networks and help to identify past and ongoing evolution of Earth’s landscape.
FRY, a global database of fire patch functional traits derived from space-borne burned area products
Authors: Laurent Pierre , Mouillot Florent , Yue Chao , Ciais Philippe , Moreno M. Vanesa , Nogueira Joana M. P. 
Published: July 2018

AbstractVegetation fires are intrinsic ecosystem disturbances of the Earth system. Global burned area products have been delivered from several space-borne instruments, and have recently provided pixel-level information underpinning fire spread processes. Here we present FRY, a global database of fire patches with morphology-based functional traits reconstructed from pixel-based burned areas derived from the MODIS and MERIS imagery using a flood-fill algorithm. Each fire patch is characterized by the geo-location of its center, area, perimeter, the features of the ellipse fitted over its pixel’s spatial distribution, and different indices of patch complexity. We obtained a consistent spatial distribution of global fire patch functional traits between the MCD64A1 Collection 6 and the MERIS fire_cci v4.1 datasets during their overlap period (2005-2011), confirming the robustness of the applied algorithm and the consistency between both products. This database is relevant to a broad spectrum of fire-related applications such as local to global functional pyrodiversity, fire emissions quantification, and the benchmarking of fire modules embedded in dynamic global vegetation models.
Full body mobile brain-body imaging data during unconstrained locomotion on stairs, ramps, and level ground
Authors: Brantley Justin A. , Luu Trieu Phat , Nakagome Sho , Zhu Fangshi , Contreras-Vidal Jose L. 
Published: July 2018

AbstractHuman locomotion is a complex process that requires the integration of central and peripheral nervous signalling. Understanding the brain’s involvement in locomotion is challenging and is traditionally investigated during locomotor imagination or observation. However, stationary imaging methods lack the ability to infer information about the peripheral and central signalling during actual task execution. In this report, we present a dataset containing simultaneously recorded electroencephalography (EEG), lower-limb electromyography (EMG), and full body motion capture recorded from ten able-bodied individuals. The subjects completed an average of twenty trials on an experimental gait course containing level-ground, ramps, and stairs. We recorded 60-channel EEG from the scalp and 4-channel EOG from the face and temples. Surface EMG was recorded from six muscle sites bilaterally on the thigh and shank. The motion capture system consisted of seventeen wireless IMUs, allowing for unconstrained ambulation in the experimental space. In this report, we present the rationale for collecting these data, a detailed explanation of the experimental setup, and a brief validation of the data quality.
A functional trait database for Mediterranean Basin plants
Authors: Tavşanoğlu Çağatay , Pausas Juli G. 
Published: July 2018

AbstractFunctional trait databases are emerging as crucial tools for a wide range of ecological studies across the world. Here, we provide a database of functional traits for vascular plant species of the Mediterranean Basin. The database includes 25,764 individual records of 44 traits from 2,457 plant taxa distributed in 119 taxonomic families. This database (BROT 2.0) is an updated and enlarged version of a previous database (BROT 1.0; 8,263 records, 14 traits, 952 taxa). Trait data were obtained from a comprehensive literature review, plus some field and experimental observations. All records are fully referenced and, in many cases, include geographic coordinates. The database is structured to include different levels of accuracy of trait information for each entry. BROT 2.0 should facilitate testing hypotheses on plant functional ecology within the Mediterranean Basin, and comparing this region with other ecosystems worldwide. The BROT 2.0 database and its trait definitions can be used as a template for creating similar trait databases in other regions of the world.
Investigating 4D coronal heating events in magnetohydrodynamic simulations
Authors: Kanella Charalambos , Gudiksen Boris V. 
Published: July 2018

Context. One candidate model for heating the solar corona is magnetic reconnection that embodies Ohmic dissipation of current sheets. When numerous small-scale magnetic reconnection events occur, then it is possible to heat the corona; if ever observed, these events would have been the speculated nanoflares.
Aims. Because of the limitations of current instrumentation, nanoflares cannot be resolved. But their importance is evaluated via statistics by finding the power-law index of energy distribution. This method is however biased for technical and physical reasons. We aim to overcome limitations imposed by observations and statistical analysis. This way, we identify, and study these small-scale impulsive events.
Methods. We employed a three-dimensional magnetohydrodynamic (3D MHD) simulation using the Bifrost code. We also employed a new technique to identify the evolution of 3D joule heating events in the corona. Then, we derived parameters describing the heating events in these locations, studied their geometrical properties and where they occurred with respect to the magnetic field.
Results. We report on the identification of heating events. We obtain the distribution of duration, released energy, and volume. We also find weak power-law correlation between these parameters. In addition, we extract information about geometrical parameters of 2D slices of 3D events, and about the evolution of resolved joule heating compared to the total joule heating and magnetic energy in the corona. Furthermore, we identify relations between the location of heating events and the magnetic field.
Conclusions. Even though the energy power index is less than 2, when classifying the energy release into three categories with respect to the energy release (pico-, nano-, and micro-events), we find that nano-events release 82% of the resolved energy. This percentage corresponds to an energy flux larger than that needed to heat the corona. Although no direct conclusions can be drawn, it seems that the most popular population among small-scale events is the one that contains nano-scale energetic events that are short lived with small spatial extend. Generally, the locations and size of heating events are affected by the magnitude of the magnetic field.
Estimating activity cycles with probabilistic methods
Authors: Olspert N. , Lehtinen J. J. , Käpylä M. J. , Pelt J. , Grigorievskiy A. 
Published: July 2018

Context. Debate over the existence of branches in the stellar activity-rotation diagrams continues. Application of modern time series analysis tools to study the mean cycle periods in chromospheric activity index is lacking.Aims. We develop such models, based on Gaussian processes (GPs), for one-dimensional time series and apply it to the extended Mount Wilson Ca H&K sample. Our main aim is to study how the previously commonly used assumption of strict harmonicity of the stellar cycles as well as handling of the linear trends affect the results.Methods. We introduce three methods of different complexity, starting with Bayesian harmonic regression model, followed by GP regression models with periodic and quasi-periodic covariance functions. We also incorporate a linear trend as one of the components. We construct rotation to magnetic cycle period ratio-activity (RCRA) diagrams and apply a Gaussian mixture model to learn the optimal number of clusters explaining the data.Results. We confirm the existence of two populations in the RCRA diagram; this finding is robust with all three methods used. We find only one significant trend in the inactive population, namely that the cycle periods get shorter with increasing rotation, leading to a positive slope in the RCRA diagram. This is in contrast with earlier studies, that postulate the existence of trends of different types in both of the populations. Our data is consistent with only two activity branches (inactive, transitional) instead of three (inactive, active, transitional) such that the active branch merges together with the transitional one. The retrieved stellar cycles are uniformly distributed over theRHK′activity index, indicating that the operation of stellar large-scale dynamos carries smoothly over the Vaughan-Preston gap. At around the solar activity index, however, indications of a disruption in the cyclic dynamo action are seen.Conclusions. Our study shows that stellar cycle estimates from time series the length of which is short in comparison to the searched cycle itself depend significantly on the model applied. Such model-dependent aspects include the improper treatment of linear trends, while the assumption of strict harmonicity can result in the appearance of double cyclicities that seem more likely to be explained by the quasi-periodicity of the cycles. In the case of quasi-periodic GP models, which we regard the most physically motivated ones, only 15 stars were found with statistically significant cycles against red noise model. The periodicities found have to, therefore, be regarded as suggestive.
Super-Earth of 8M⊕in a 2.2-day orbit around the K5V star K2-216
Authors: Persson C. M. , Fridlund M. , Barragán O. , Dai F. , Gandolfi D. , Hatzes A. P. , Hirano T. , Grziwa S. , Korth J. , Prieto-Arranz J. , Fossati L. , Van Eylen V. , Justesen A. B. , Livingston J. , Kubyshkina D. , Deeg H. J. , Guenther E. W. , Nowak G. , Cabrera J. , Eigmüller Ph. , Csizmadia Sz. , Smith A. M. S. , Erikson A. , Albrecht S. , Sobrino Alonso , Cochran W. D. , Endl M. , Esposito M. , Fukui A. , Heeren P. , Hidalgo D. , Hjorth M. , Kuzuhara M. , Narita N. , Nespral D. , Palle E. , Pätzold M. , Rauer H. , Rodler F. , Winn J. N. 
Published: July 2018

Context.Although thousands of exoplanets have been discovered to date, far fewer have been fully characterised, in particular super-Earths. The KESPRINT consortium identified K2-216 as a planetary candidate host star in the K2 space mission Campaign 8 field with a transiting super-Earth. The planet has recently been validated as well.Aims.Our aim was to confirm the detection and derive the main physical characteristics of K2-216 b, including the mass.Methods.We performed a series of follow-up observations: high-resolution imaging with the FastCam camera at the TCS and the Infrared Camera and Spectrograph at Subaru, and high-resolution spectroscopy with HARPS (La Silla), HARPS-N (TNG), and FIES (NOT). The stellar spectra were analyzed with theSpecMatch-EmpandSMEcodes to derive the fundamental stellar properties. We analyzed the K2 light curve with thepyanetisoftware. The radial velocity measurements were modelled with both a Gaussian process (GP) regression and the so-called floating chunk offset (FCO) technique to simultaneously model the planetary signal and correlated noise associated with stellar activity.Results.Imaging confirms that K2-216 is a single star. Our analysis discloses that the star is a moderately active K5V star of mass 0.70 ± 0.03M⊙and radius 0.72 ± 0.03R⊙. Planet b is found to have a radius of 1.75−0.10+0.17R⊕and a 2.17-day orbit in agreement with previous results. We find consistent results for the planet mass from both models:Mp≈ 7.4 ± 2.2M⊕from the GP regression andMp≈ 8.0 ± 1.6M⊕from the FCO technique, which implies that this planet is a super-Earth. The incident stellar flux is 2.48−48+220F⊕.Conclusions.The planet parameters put planet b in the middle of, or just below, the gap of the radius distribution of small planets. The density is consistent with a rocky composition of primarily iron and magnesium silicate. In agreement with theoretical predictions, we find that the planet is a remnant core, stripped of its atmosphere, and is one of the largest planets found that has lost its atmosphere.
The Close AGN Reference Survey (CARS)
Authors: Powell M. C. , Husemann B. , Tremblay G. R. , Krumpe M. , Urrutia T. , Baum S. A. , Busch G. , Combes F. , Croom S. M. , Davis T. A. , Eckart A. , O’Dea C. P. , Pérez-Torres M. , Scharwächter J. , Smirnova-Pinchukova I. , Urry C. M. 
Published: July 2018

Aims. We probe the radiatively-efficient, hot wind feedback mode in two nearby luminous unobscured (type 1) AGN from the Close AGN Reference Survey (CARS), which show intriguing kpc-scale arc-like features of extended [O III]ionized gas as mapped with VLT-MUSE. We aimed to detect hot gas bubbles that would indicate the existence of powerful, galaxy-scale outflows in our targets, HE 0227–0931 and HE 0351+0240, from deep (200 ks)Chandraobservations.Methods. By measuring the spatial and spectral properties of the extended X-ray emission and comparing with the sub kpc-scale IFU data, we are able to constrain feedback scenarios and directly test if the ionized gas is due to a shocked wind.Results. No extended hot gas emission on kpc-scales was detected. Unless the ambient medium density is low (nH  ∼  1 cm−3at 100 pc), the inferred upper limits on the extended X-ray luminosities are well below what is expected from theoretical models at matching AGN luminosities.Conclusions. We conclude that the highly-ionized gas structures on kpc scales are not inflated by a hot outflow in either target, and instead are likely caused by photoionization of pre-existing gas streams of different origins. Our nondetections suggest that extended X-ray emission from an AGN-driven wind is not universal, and may lead to conflicts with current theoretical predictions.
Association of Serum Leptin with All-Cause and Disease Specific Mortality: A Meta-Analysis of Prospective Observational Studies
Authors: Kord-Varkaneh Hamed , Fatahi Somaye , Alizadeh Shahab , Ghaedi Ehsan , Shab-Bidar Sakineh 
Published: July 2018

AbstractLeptin levels may affect mortality through its link to inflammation and obesity. However, data are inconclusive. This meta-analysis was performed to investigate the association of leptin with mortality. The PubMed, Scopus, Google scholar, and reference lists of the included studies were searched for all published prospective observational studies that described the associations of serum leptin and mortality up to August 2017. Two reviewers independently assessed all potentially relevant studies for inclusion and methodological quality using standardized abstraction forms. Of 518 studies identified, 19 studies considered the association of leptin with all-cause mortality (16 208 subjects) and 12 studies evaluated the association of leptin with disease-specific mortality (13 680 subjects). In the overall analysis, no significant association was found between leptin and all-cause mortality (HR=1.028; 95% CI: 0.908–1.165; p=0.659), with a high between study heterogeneity (p˂0.001, I2=61). Subgroup analysis found that high leptin is associated with increased all-cause mortality in healthy people (HR=1.159 (95% CI, 1.032, 1.302), p=0.012), in men (HR=1.162; 95% CI: 1.036–1.302; p=0.010), and in subjects with ≥60 years old (HR=1.129; 95% CI: 1.030–1.238; p=0.010); whereas, increased leptin levels was related to the decreased cancer-specific mortality ((HR=0.550; 95% CI: 0.418–0.724), p˂0.001). Higher leptin levels in healthy people, old people, and males were associated with increased all-cause mortality, while increased leptin level was related to the reduced risk of death among patients with cancer.
A systematic review of advanced endoscopy-assisted lithotripsy for retained biliary tract stones: laser, electrohydraulic or extracorporeal shock wave
Authors: Veld Joyce , van Huijgevoort Nadine , Boermeester Marja , Besselink Marc , van Delden Otto , Fockens Paul , van Hooft Jeanin 
Published: July 2018

Abstract
Background When conventional endoscopic treatment of bile duct stones is impossible or fails, advanced endoscopy-assisted lithotripsy can be performed by electrohydraulic lithotripsy (EHL), laser lithotripsy, or extracorporeal shock wave lithotripsy (ESWL). No systematic review has compared efficacy and safety between these techniques.
Methods A systematic search was performed in PubMed, the Cochrane Library, and EMBASE for studies investigating EHL, laser lithotripsy, and ESWL in patients with retained biliary tract stones.
Results After screening 795 studies, 32 studies with 1969 patients undergoing EHL (n = 277), laser lithotripsy (n = 426) or ESWL (n = 1266) were included. No randomized studies were available. Although each advanced lithotripsy technique appeared to be highly effective, laser lithotripsy had a higher complete ductal clearance rate (95.1 %) than EHL (88.4 %) and ESWL (84.5 %; P  < 0.001). In addition, a higher stone fragmentation rate was reported for laser lithotripsy (92.5 %) than for EHL (75.5 %) and ESWL (89.3 %; P < 0.001). The post-procedural complication rate was significantly higher for patients treated with EHL (13.8 %) than for patients treated with ESWL (8.4 %) or laser lithotripsy (9.6 %; P = 0.04). Data on the recurrence rate of the biliary tract stones were lacking.
Conclusion This systematic review revealed that laser lithotripsy appeared to be the most successful advanced endoscopy-assisted lithotripsy technique for retained biliary tract stones, although randomized studies are lacking.
Self-expandable metal stent placement for malignant esophageal strictures – changes in clinical outcomes over time
Authors: Reijm Agnes , Didden Paul , Schelling Sara , Siersema Peter , Bruno Marco , Spaander Manon 
Published: July 2018

Abstract
Background Self-expandable metal stents (SEMSs) are effective for improving dysphagia in patients with incurable esophageal cancer but are also associated with recurrent dysphagia and adverse events. In the past decades, new SEMSs have been introduced, but also patients’ risk profiles have altered. It is unknown if these changes have affected SEMS outcomes.
Methods This retrospective cohort study was conducted in a tertiary referral center in the Netherlands. Patients who underwent palliative esophageal SEMS placement for malignant dysphagia between 1994 and 2017 were included. The primary outcome was to assess shifts over time with respect to recurrent dysphagia and adverse events after SEMS placement.
Results 997 patients who underwent SEMS placement were included. Recurrent dysphagia occurred in 309 patients (31 %) and remained stable, although with a trend towards an increase over time (hazard ratio [HR] 1.02 per 1-year increase; P = 0.05). Migration rate significantly increased over time (HR 1.04 per 1-year increase; P = 0.01). SEMS-related complications occurred in 461 patients (46.2 %), with 207 (20.7 %) major and 336 (33.7 %) minor complications. Prior chemoradiotherapy was significantly associated with major complications (HR 1.69; P < 0.001). Pain was the most common adverse event and showed a significant increase over time (P < 0.01). Factors associated with pain were prior chemoradiotherapy, absence of a fistula, axial and radial forces, and squamous cell carcinoma.
Conclusions Despite the introduction of novel esophageal SEMS designs, recurrent dysphagia has not declined over the years. Stent-related complications have increased in recent years, which seems to be mainly associated with more frequent use of chemoradiotherapy prior to SEMS placement.
Antimicrobial Dialkylresorcins from Marine-Derived Microorganisms: Insights into Their Mode of Action and Putative Ecological Relevance
Authors: Harms Henrik , Klöckner Anna , Schrör Jan , Josten Michaele , Kehraus Stefan , Crüsemann Max , Hanke Wiebke , Schneider Tanja , Schäberle Till , König Gabriele 
Published: July 2018

Abstract
Zobellia galactanivorans has been reported as a seaweed-associated or marine-derived species with largely unknown secondary metabolites. The combination of bioinformatic analysis and MS- and bioactivity guided separation led to the isolation of a new antibiotically active dialkylresorcin from the marine bacterium Z. galactanivorans. The antibiotic profile of the new dialkylresorcin zobelliphol (1) was investigated and compared with related and naturally occurring dialkyresorcins (i.e., stemphol (2) and 4-butyl-3,5-dihydroxybenzoic acid (3)) from the marine-derived fungus Stemphylium globuliferum. Bacterial reporter strain assays provided insights into the mode of action of this antibiotic compound class. We identified an interference with bacterial DNA biosynthesis for the dialkylresorcin derivative 1. In addition, the putative biosynthetic gene cluster corresponding to production of 1 was identified and a biosynthetic hypothesis was deduced.
Severe Type I Protein C Deficiency in a Compound Heterozygote for Y124C and Q132X Mutations in Exon 6 of the PROC Gene
Authors: Soria José Manuel , Morell Marta , Jimeénez-Astorga Carmen , Estivill Xavier , Sala Nuúria 
Published: July 2018

SummaryWe report the genetic abnormalities in the protein C genes of a Spanish child with neonatal purpura fulminans and disseminated intravascular coagulation, associated with undetectable protein C levels. Direct sequencing of the nine protein C gene exons and their splice junctions indicated that the proband is a compound heterozygote with two mutant protein C gene alleles, Y124C and Q132X, that do not express protein C in plasma. The Y124C mutation was inherited from the mother and is due to a novel A to G transition at nucleotide 3416, which results in the substitution of cysteine for tyrosine 124, a highly conserved amino acid in EGF-like domains. The paternal inherited mutation (Q132X) is a C to T transition at nucleotide 3439, which replaces glutamine 132 with a Stop codon signal. This mutation, if expressed, should result in the synthesis of a truncated protein of 131 amino acids. Y124C or Q132X are present in the heterozygous state in the asymptomatic parents and siblings of the proband, all of which have half the normal plasma levels of protein C. Q123X has also been identified in families where type I PC deficiency is inherited as a clinically dominant trait. Therefore, the presence of the same mutation in a family showing a clinically recessive pattern of inheritance indicates that other factors, apart from the type of protein C gene mutation, are responsible for the clinical expression of protein C deficiency.