bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decaying Lava Extrusion Rate at El Reventador Volcano, Ecuador, Measured Using High‐Resolution Satellite Radar
Authors: Arnold D. W. D. , Biggs J. , Anderson K. , Vallejo Vargas S. , Wadge G. , Ebmeier S. K. , Naranjo M. F. , Mothes P. 
Published: December 2017

AbstractLava extrusion at erupting volcanoes causes rapid changes in topography and morphology on the order of tens or even hundreds of meters. Satellite radar provides a method for measuring changes in topographic height over a given time period to an accuracy of meters, either by measuring the width of radar shadow cast by steep sided features, or by measuring the difference in radar phase between two sensors separated in space. We measure height changes, and hence estimate extruded lava volume flux, at El Reventador, Ecuador, between 2011 and 2016, using data from the RADARSAT‐2 and TanDEM‐X satellite missions. We find that 39 new lava flows were extruded between 9 February 2012 and 24 August 2016, with a cumulative volume of 44.8M m3 dense rock equivalent and a gradually decreasing eruption rate. The average dense rock rate of lava extrusion during this time is 0.31 ± 0.02 m3 s−1, which is similar to the long‐term average from 1972 to 2016. Apart from a volumetrically small dyke opening event between 9 March and 10 June 2012, lava extrusion at El Reventador is not accompanied by any significant magmatic ground deformation. We use a simple physics‐based model to estimate that the volume of the magma reservoir under El Reventador is greater than 3 km3. Our lava extrusion data can be equally well fit by models representing a closed reservoir depressurising during the eruption with no magma recharge, or an open reservoir with a time‐constant magma recharge rate of up to 0.35 ± 0.01 m3 s−1.
CubeSats in Hydrology: Ultrahigh‐Resolution Insights Into Vegetation Dynamics and Terrestrial Evaporation
Authors: McCabe M. F. , Aragon B. , Houborg R. , Mascaro J. 
Published: December 2017

AbstractSatellite‐based remote sensing has generally necessitated a trade‐off between spatial resolution and temporal frequency, affecting the capacity to observe fast hydrological processes and rapidly changing land surface conditions. An avenue for overcoming these spatiotemporal restrictions is the concept of using constellations of satellites, as opposed to the mission focus exemplified by the more conventional space‐agency approach to earth observation. Referred to as CubeSats, these platforms offer the potential to provide new insights into a range of earth system variables and processes. Their emergence heralds a paradigm shift from single‐sensor launches to an operational approach that envisions tens to hundreds of small, lightweight, and comparatively inexpensive satellites placed into a range of low earth orbits. Although current systems are largely limited to sensing in the optical portion of the electromagnetic spectrum, we demonstrate the opportunity and potential that CubeSats present the hydrological community via the retrieval of vegetation dynamics and terrestrial evaporation and foreshadow future sensing capabilities.
Dendron‐Grafted Polylysine‐Based Dual‐Modal Nanoprobe for Ultra‐Early Diagnosis of Pancreatic Precancerosis via Targeting a Urokinase‐Type Plasminogen Activator Receptor
Authors: Li Hui , Wang Ping , Gong Wenyu , Wang Qi , Zhou Jia , Zhu Wei‐Hong , Cheng Yingsheng 
Published: December 2017

AbstractPancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer death. Early detection of precancerous pancreatic intraepithelial neoplasia (PanIN) tissues is an urgent challenge to improve the PDAC prognosis. Here, a urokinase‐type plasminogen activator receptor (uPAR)‐targeted magnetic resonance (MR)/near‐infrared fluorescence (NIRF) dual‐modal nanoprobe dendron‐grafted polylysine (DGL)‐U11 for ultra‐early detection of pancreatic precancerosis is reported. Because of its good biocompatibility and biodegradability, globular architecture, and well‐defined reactive groups, the DGL is chosen as the platform to load with a pancreatic tumor‐targeting peptide U11, a magnetic resonance contrast agent Gd3+‐diethylene triamine pentaacetic acid, and a near‐infrared fluorescent cyanine dye Cy5.5. The nanoprobe DGL‐U11 has several preferable characteristics, such as active peptide targeting to activator receptor, good biocompatibility, dual‐modal imaging diagnosis, and well controlled diameter in a range of 15–25 nm. Upon incorporation of the active U11 peptide target to the overexpressed activator receptor uPAR, the targeted nanoprobe DGL‐U11 can increase to the earlier PanIN‐II stage through in vivo NIRF imaging. Labeled with both MR and NIRF bioimaging reporters, the uPAR‐targeted dual‐modal nanoprobe is very effective in the targeted imaging of precancerous PanINs and PDAC lesions with high sensitivity and spatial resolution, providing a promising platform to the ultra‐early detection of PDAC.
High and Fast Response of a Graphene–Silicon Photodetector Coupled with 2D Fractal Platinum Nanoparticles
Authors: Huang Kun , Yan Yucong , Li Ke , Khan Afzal , Zhang Hui , Pi Xiaodong , Yu Xuegong , Yang Deren 
Published: December 2017

Abstract2D material‐based electronic devices like graphene–silicon photodetectors (Gr–Si PDs) have attracted much attention of researchers in the past few years. Due to the nature of Schottky junction, Gr–Si PDs have ultrafast response. However, responsivity of Gr–Si PDs is very low, which hinders their practical application. Low work function of Gr and poor absorbance of Si are mainly responsible for this problem. Here, a novel approach for coupling of Gr–Si PDs with 2D fractal platinum nanoparticles (Pt NPs) is demonstrated to enhance the responsivity and speed up the response of Gr–Si PDs at the same time. 2D morphology of fractal Pt NPs helps to overcome the coffee‐ring effect. Fully covered fractal Pt NPs remarkably improve the absorption of Gr–Si PDs by plasmonic effect. Responsivity of Gr–Si PDs thus is remarkably enhanced to 26 A W−1. Meanwhile, work function of Gr is improved by the physical doping of high‐work‐function Pt NPs. Therefore, the Schottky barrier of Gr–Si junction is increased, resulting in faster response. Improvement in the built‐in electric field reduces the background noise of Gr–Si PDs as well. These results indicate toward a simple and novel approach for fabricating high and fast response Gr–Si PDs.
Generation of Radial Polarized Lorentz Beam with Single Layer Metasurface
Authors: Guo Jin‐Ying , Wang Xin‐Ke , He Jing‐Wen , Zhao Huan , Feng Sheng‐Fei , Han Peng , Ye Jia‐Sheng , Sun Wen‐Feng , Situ Guo‐Hai , Zhang Yan 
Published: December 2017

AbstractA radially polarized Lorentz beam is demonstrated in the terahertz waveband with a single layer metasurface. Composed of cross antennas of various sizes and orientation, the metasurface performs simultaneously a continuous amplitude modulation and a controlled polarization spatial redistribution of incident waves of wavelength 400 µm. The metasurface device is designed and characterized using a terahertz time domain spectral imaging system. Experimental results are consistent with theoretical calculations. With the advantage of compactness and simplicity, this device may be applied to generate various complex light fields and in the reconstruction of computer‐generated polarization hologram.
Noncovalent Interactions of π Systems with Sulfur: The Atomic Chameleon of Molecular Recognition
Authors: Motherwell William B. , Moreno Rafael B. , Pavlakos Ilias , Arendorf Josephine R. T. , Arif Tanzeel , Tizzard Graham J. , Coles Simon J. , Aliev Abil E. 
Published: December 2017

AbstractThe relative strength of noncovalent interactions between a thioether sulfur atom and various π systems in designed top pan molecular balances was determined by NMR spectroscopy. Compared to its oxygen counterpart, the sulfur atom displays a remarkable ability to interact with almost equal facility over the entire range of π systems studied, with the simple alkene emerging as the most powerful partner. With the exception of the O⋅⋅⋅heteroarene interaction, all noncovalent interactions of sulfur with π systems are favoured over oxygen.
Ontogeny of Surface Texture of Limb Bones in Modern Aquatic Birds and Applicability of Textural Ageing
Authors: Watanabe Junya 
Published: December 2017

ABSTRACTDespite its importance in various disciplines, a general method to assess ontogenetic ages of skeletal and fossil specimens has been lacking for birds. Although the textural ageing method was formulated to assess relative ontogenetic ages of specimens from inspection of bone surface textures, the exact correspondence of surface textures to ontogenetic stages has not yet been clear. In this study, bone surface textures of six major limb bones (humerus, ulna, carpometacarpus, femur, tibiotarsus, and tarsometatarsus) were described in postnatal ontogenies of four species of modern birds (Calonectris leucomelas, Phalacrocorax capillatus, Larus crassirostris, and Cerorhinca monocerata) from 14 to 28 individuals of known ontogenetic stages for each species. Consistently with the previous postulation, it was found that bones of chicks were characterized by rough surface textures with numerous grooves/depressions that host minute foramina. Bones of fledglings/juveniles, which are generally as large as those of adults but more slender, were characterized by the occasional presence of depressions and foramina. Histological observations confirmed that these rough surface textures were underlain by fibrolamellar bone tissue which is associated with active periosteal ossification. These results indicate that the smooth surface texture in adults is formed after the cessation of circumferential bone growth, which probably takes place between fledging and the attainment of sexual maturity. The available evidence suggests that the textural ageing is probably applicable to the entire Neognathae, a clade containing most crown‐group birds. Anat Rec, 301:1026–1045, 2018. © 2017 Wiley Periodicals, Inc.
Computational Fluid Dynamics Simulation of Generation and Coalescence of Bubbles in Non‐Newtonian Fluids
Authors: Zhu Chunying , Yang Hui , Fu Taotao , Gao Xiqun , Ma Youguang 
Published: December 2017

AbstractThe successive generation and coalescence behaviors of bubbles from two parallel nozzles in non‐Newtonian fluids were numerically simulated by using the volume of fluid (VOF) method. Three flow patterns for bubbles and the related flow regime transition lines were obtained. Two critical nozzle intervals exist: one for the bubble coalescence before pinch‐off, and another for alternating bubble formation then in‐line coalescence under different conditions. Two correlations were proposed to predict the dimensionless critical nozzle intervals for the transition of bubble‐flow patterns. The influences of nozzle diameter, gas flow rate, nozzle interval, and rheological properties of fluid on bubble‐flow patterns were investigated systematically.
Monosaccharide Derivatives with Low‐Nanomolar Lectin Affinity and High Selectivity Based on Combined Fluorine–Amide, Phenyl–Arginine, Sulfur–π, and Halogen Bond Interactions
Authors: Zetterberg Fredrik R. , Peterson Kristoffer , Johnsson Richard E. , Brimert Thomas , Håkansson Maria , Logan Derek T. , Leffler Hakon , Nilsson Ulf J. 
Published: December 2017

AbstractThe design of small and high‐affinity lectin inhibitors remains a major challenge because the natural ligand binding sites of lectin are often shallow and have polar character. Herein we report that derivatizing galactose with un‐natural structural elements that form multiple non‐natural lectin–ligand interactions (orthogonal multipolar fluorine–amide, phenyl–arginine, sulfur–π, and halogen bond) can provide inhibitors with extraordinary affinity (low nanomolar) for the model lectin, galectin‐3, which is more than five orders of magnitude higher than the parent galactose; moreover, is selective over other galectins.
A general modeling framework for describing spatially structured population dynamics
Authors: Sample Christine , Fryxell John M. , Bieri Joanna A. , Federico Paula , Earl Julia E. , Wiederholt Ruscena , Mattsson Brady J. , Flockhart D. T. Tyler , Nicol Sam , Diffendorfer Jay E. , Thogmartin Wayne E. , Erickson Richard A. , Norris D. Ryan 
Published: December 2017

AbstractVariation in movement across time and space fundamentally shapes the abundance and distribution of populations. Although a variety of approaches model structured population dynamics, they are limited to specific types of spatially structured populations and lack a unifying framework. Here, we propose a unified network‐based framework sufficiently novel in its flexibility to capture a wide variety of spatiotemporal processes including metapopulations and a range of migratory patterns. It can accommodate different kinds of age structures, forms of population growth, dispersal, nomadism and migration, and alternative life‐history strategies. Our objective was to link three general elements common to all spatially structured populations (space, time and movement) under a single mathematical framework. To do this, we adopt a network modeling approach. The spatial structure of a population is represented by a weighted and directed network. Each node and each edge has a set of attributes which vary through time. The dynamics of our network‐based population is modeled with discrete time steps. Using both theoretical and real‐world examples, we show how common elements recur across species with disparate movement strategies and how they can be combined under a unified mathematical framework. We illustrate how metapopulations, various migratory patterns, and nomadism can be represented with this modeling approach. We also apply our network‐based framework to four organisms spanning a wide range of life histories, movement patterns, and carrying capacities. General computer code to implement our framework is provided, which can be applied to almost any spatially structured population. This framework contributes to our theoretical understanding of population dynamics and has practical management applications, including understanding the impact of perturbations on population size, distribution, and movement patterns. By working within a common framework, there is less chance that comparative analyses are colored by model details rather than general principles.
Somatotopic effects of rTMS in neuropathic pain? A comparison between stimulation over hand and face motor areas
Authors: Andre‐Obadia N. , Magnin M. , Simon E. , Garcia‐Larrea L. 
Published: December 2017

AbstractBackgroundThe therapeutic influence of somatotopic matching between pain topography and motor cortex stimulation site for neuropathic pain (NP) remains controversial.MethodsThirty‐two patients suffering from NP involving the upper limb (n = 20) or the face (n = 12) received two high‐frequency rTMS neuronavigated sessions targeting hand and face motor cortical areas, versus placebo. The cortical target was defined by anatomical MRI and EMG responses in all patients, completed in 19 of them by functional MRI. Sessions were separated by at least 2 weeks and applied in random order. Pain relief was assessed using numerical rating scale (NRS).ResultsIn terms of percentage of pain relief, rTMS over the hand motor area was significantly superior to both face rTMS and placebo. When comparing pre‐ and post‐NRS scores, a significant decrease in pain was observed after hand area rTMS for the two pain localizations, while stimulation of the face area induced a slight but nonsignificant effect on upper limb pain after correction. Sham‐rTMS did not exert any effect. The percentage of patients with clinically significant (>30%) or mild (15–30%) pain relief did not differ, however, between rTMS addressed to the hand or face area.ConclusionsThe results do not support a somatotopic effect of motor rTMS for NP. Lack of clinically relevant somatotopic effects in upper limb or face pain suggests that much of the rTMS analgesic effect may depend on high‐order mechanisms involving cognitive and affective appraisal of pain, rather than on a sensory effect related to the specific motor area stimulated.SignificanceStrict somatotopic targeting of rTMS does not appear warranted for the treatment of upper limb or face NP. Since the hand motor area is easier to target and provides better results, it might be privileged for both types of pain.
A Self‐assembled L‐Cysteine and Electrodeposited Gold Nanoparticles‐reduced Graphene Oxide Modified Electrode for Adsorptive Stripping Determination of Copper
Authors: Yiwei Xu , Wen Zhang , Xiaowei Huang , Jiyong Shi , Xiaobo Zou , Yanxiao Li , Xueping Cui , Tahir Haroon Elrasheid , Zhihua Li 
Published: December 2017

AbstractGlassy carbon electrode (GCE) modified with L‐cysteine and gold nanoparticles‐reduced graphene oxide (AuNPs‐RGO) composite was fabricated as a novel electrochemical sensor for the determination of Cu2+. The AuNPs‐RGO composite was formed on GCE surface by electrodeposition. The L‐cysteine was decorated on AuNPs by self‐assembly. Physicochemical and electrochemical properties of L‐cysteine/AuNPs‐RGO/GCE were characterized by scanning electron microscopy, atomic force microscopy, energy dispersive spectroscopy, Raman spectroscopy, X‐ray diffraction, cyclic voltammetry and adsorptive stripping voltammetry. The results validated that the prepared electrode had many attractive features, such as large electroactive area, good electrical conductivity and high sensitivity. Experimental conditions, including electrodeposition cycle, self‐assembly time, electrolyte pH and preconcentration time were studied and optimized. Stripping signals obtained from L‐cysteine/AuNPs‐RGO/GCE exhibited good linear relationship with Cu2+ concentrations in the range from 2 to 60 μg L−1, with a detection limit of 0.037 μg L−1. Finally, the prepared electrode was applied for the determination of Cu2+ in soil samples, and the results were in agreement with those obtained by inductively coupled plasma mass spectrometry.
The Sticky Standard of Care
Authors: Oberman Michelle 
Published: December 2017

AbstractThe problem at the heart of “Stemming the Standard‐of‐Care Sprawl: Clinician Self‐Interest and the Case of Electronic Fetal Monitoring,” an article by Kayte Spector‐Bagdady and colleagues in the November‐December 2017 issue of the Hastings Center Report, is the persistence of a suboptimal standard of care long after evidence‐driven approaches would dictate a change. That problem is not simply defensive medicine, or what the authors call “standard‐of‐care sprawl.” Instead, it is that, in some cases, the standard of care lags behind best practices. It gets stuck. The authors point to the genesis of the stickiness problem in their passing reference to a core truth: “The problem is that standard of care is not synonymous with best or evidence‐based medicine.” In my view, we might best understand the persistence of ineffective and even harmful medical interventions by acknowledging the regulatory vacuum in which such practices thrive. It is by default, not by design, that the profession relies on medical malpractice law to set the boundaries on acceptable practice.
Disparities in direct acting antivirals uptake in HIV‐hepatitis C co‐infected populations in Canada
Authors: Saeed Sahar , Strumpf Erin C , Moodie Erica EM , Young Jim , Nitulescu Roy , Cox Joseph , Wong Alexander , Walmsely Sharon , Cooper Curtis , Vachon Marie‐Lousie , Martel‐Laferriere Valerie , Hull Mark , Conway Brian , Klein Marina B ,   the Canadian Co‐Infection Cohort Study
Published: December 2017

AbstractBackgroundDirect acting antivirals (DAAs) have revolutionized hepatitis C (HCV) treatment with >90% cure rates even in real‐world studies, giving hope that HCV can be eliminated. However, for DAAs to have a population‐level impact on the burden of HCV disease, treatment uptake needs to be expanded. We investigated temporal trends in HCV treatment uptake and evaluated factors associated with second‐generation DAA initiation and efficacy among key HIV‐HCV co‐infected populations in Canada.MethodsThe Canadian HIV‐HCV Co‐Infection Cohort Study prospectively follows 1699 participants from 18 centres. Among HCV RNA+ participants, we determined the incidence of HCV treatment initiation per year overall and by key populations between 2007 and 2015. Key populations were based on World Health Organization (WHO) guidelines including: people who actively inject drugs (PWID) (reporting injection drug use, last 6 months); Indigenous people; women and men who have sex with men (MSM). Multivariate Cox models were used to estimate adjusted hazard ratios (aHR) and 2‐year probability of initiating second‐generation DAAs for each of the key populations.ResultsOverall, HCV treatment initiation rates increased from 8 (95% CI, 6–11) /100 person‐years in 2013 to 28 (95% CI, 23–33) /100 person‐years in 2015. Among 911 HCV RNA + participants, there were 202 second‐generation DAA initiations (93% with interferon‐free regimens). After adjustment (aHR, 95% CI), active PWID (0.60, 0.38–0.94 compared to people not injecting drugs) and more generally, people with lower income (<$18 000 CAD/year) (0.50, 0.35, 0.71) were less likely to initiate treatment. Conversely, MSM were more likely to initiate 1.95 (1.33, 2.86) compared to heterosexual men. In our cohort, the population profile with the lowest 2‐year probability of initiating DAAs was Indigenous, women who inject drugs (5%, 95% CI 3–8%). Not having any of these risk factors resulted in a 35% (95% CI 32–38%) probability of initiating DAA treatment. Sustained virologic response (SVR) rates were >82% in all key populations.ConclusionWhile treatment uptake has increased with the availability of second‐generation DAAs, marginalized populations, already engaged in care, are still failing to access treatment. Targeted strategies to address barriers are needed to avoid further health inequities and to maximize the public health impact of DAAs.
Taxon‐specific contributions to silica production in natural diatom assemblages
Authors: McNair Heather M. , Brzezinski Mark A. , Till Claire P. , Krause Jeffrey W. 
Published: December 2017

AbstractThe metabolic activity and growth of phytoplankton taxa drives their ecological function and contribution to biogeochemical processes. We present the first quantitative, taxon‐resolved silica production rates, growth rates, and silica content estimates for co‐occurring diatoms along two cross‐shelf transects off the California coast using the fluorescent tracer 2‐(4‐pyridyl)‐5‐((4‐(2‐dimethylaminoethylaminocarbamoyl)methoxy)phenyl)oxazole, and confocal microscopy. Taxon contribution to total diatom community silica production was predominantly a function of the surface area (SA) of new frustule that each taxon created as opposed to cell abundance or frustule thickness. The influential role of SA made large diatoms disproportionately important to community silica production over short time scales (< 1 d). In some cases, large taxa that comprised only ∼ 15% of numerical cell abundance accounted for over 50% of total community silica production. Over longer time scales relevant to bloom dynamics, the importance of SA declines and growth rate becomes the dominant influence on contribution to production. The relative importance of SA and growth rate in relation to silica production was modeled as the time needed for a smaller, faster‐growing taxon to create more SA than a larger, slower‐growing taxon. Differences in growth rate between the taxa effected the model outcome more than differences in SA. Shifts in relative silica production among taxa are time restricted by finite resources that limit the duration of a bloom. These patterns offer clues as to how taxa respond to their environment and the consequences for both species succession and the potential diatom contribution to elemental cycling.