bluuebunny/crossref_metadata_2025 huggingface dataset:
How Accurately Can the Air Temperature Lapse Rate Over the Tibetan Plateau Be Estimated From MODIS LSTs?
Authors: Zhang Hongbo , Zhang Fan , Zhang Guoqing , Che Tao , Yan Wei
Published: March 2018

The air temperature lapse rate (TLR) is a key parameter for interpolating air temperature data in high mountainous regions such as the Tibetan Plateau (TP). The Moderate Resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) has been frequently used for estimating air temperature during the past decade, but its performance in estimating the TLR in the TP has seldom been investigated. This study employed two methods in estimating the TLR based on MODIS LSTs compared with the “observed” TLR derived from 86 stations across the TP. The two methods include a method for directly computing the lapse rate from MODIS LST (DFM) and a second method for calculating the lapse rate of estimated air temperatures based on air temperature estimation from MODIS LST (TEM). The results show that the MODIS LST‐estimated TLR for daily mean air temperature (Tmean) using both DFM and TEM is more accurate than that for daily minimum and maximum air temperatures. When using MODIS nighttime LSTs, both DFM and TEM show acceptable accuracies for estimating the TLR of Tmean with averaged root‐mean‐square deviations of 0.21 and 0.19 °C/100 m, respectively. The spatial and seasonal patterns of MODIS LST‐estimated TLRs of Tmean from both DFM and TEM are found to be highly consistent with the observed TLRs. This study can help alleviate the data‐sparse problem in downscaling air temperature or hydrological modeling studies in ungauged areas, especially for the western TP where station data are extremely scarce.
Coarse Sediment Transport in the Modern Martian Environment
Authors: Baker M. M. , Newman C. E. , Lapotre M. G. A. , Sullivan R. , Bridges N. T. , Lewis K. W.
Published: March 2018

The occurrence of regional and global dust storms, observations of migrating ripples and dunes, and the recognition of aeolian sandstone outcrops demonstrate that aeolian processes have been and continue to be a significant agent of surface modification on Mars. However, the mechanisms of aeolian transport within Mars' low atmospheric pressure surface environment are still not fully understood. This work presents a synthesis of change detection observations conducted with the Mars Science Laboratory Curiosity rover in Gale crater over three Martian years. Sediment mobility during this period was highly variable, consistent with previous orbiter‐based observations showing strong seasonal variability, with strongest winds expected during southern summer. Wind activity inferred at each change detection site helps test the accuracy of atmospheric models, as well as constrain the intensity of current atmosphere‐surface interactions and the physics of sand transport in the tenuous Martian atmosphere. Results indicate an apparent discrepancy between predicted wind speeds and the wind strengths required by classical incipient‐motion models to explain observed sediment motion. Observed mobilization of perched and/or isolated very coarse sand grains and fine pebbles (i.e., grain sizes 1 mm ≤d≤3 mm) likely requires an alternate explanation, such as very strong but infrequent wind gusts, drag‐induced rolling, or impact‐driven creep caused by smaller saltating particles.
Forest Canopy Structural Complexity and Light Absorption Relationships at the Subcontinental Scale
Authors: Atkins J. W. , Fahey R. T. , Hardiman B. S. , Gough C. M.
Published: March 2018

Understanding how the physical structure of forest canopies influences light absorption is a long‐standing area of inquiry fundamental to the physical sciences, including the modeling and interpretation of biogeochemical cycles. Conventional measures of forest canopy structure used to infer canopy light absorption are often limited to leaf or vegetation area indexes. However, LiDAR‐derived measures of canopy structural complexity (CSC) that describe the arrangement of vegetation may improve prediction of canopy light absorption by providing novel information on canopy‐light interactions not regulated by leaf area alone. We measured multiple indexes of CSC, vegetation area index (VAI), and the fraction of photosynthetically active radiation absorbed (fPAR) across the eastern United States using portable canopy LiDAR to evaluate how different canopy structural attributes relate to fPAR. Our survey included sites from the National Ecological Observation Network and university field stations. Measures of CSC were more strongly coupled with fPAR under high light (>1,000 μmol m−2 s−1PAR). Under low light conditions, when diffuse light predominates, light scattering weakens the dependency of fPAR on CSC. A multivariate model including CSC parameters and VAI explains ~89% of the intersite variance in fPAR, an improvement of over a VAI only linear model (r2 = 0.73). The inclusion of CSC metrics in canopy light absorption models could increase confidence in predictions of biogeochemical cycles and energy balance.
Water Mass Control on Phytoplankton Spatiotemporal Variations in the Northeastern East China Sea and the Western Tsushima Strait Revealed by Lipid Biomarkers
Authors: Bi Rong , Chen Xi , Zhang Jing , Ishizaka Joji , Zhuang Yanpei , Jin Haiyan , Zhang Hailong , Zhao Meixun
Published: March 2018

Continental margin ecosystems in the western North Pacific Ocean are subject to strong climate forcing and anthropogenic impacts. To evaluate mechanisms controlling phytoplankton biomass and community structure variations in marginal sea‐open ocean boundary regions, brassicasterol, dinosterol, and C37 alkenones were measured in suspended particles in summer and autumn from 2012 to 2013 in the northeastern East China Sea and the western Tsushima Strait. In summer, the concentrations of brassicasterol (40–1535 ng/L) and dinosterol (4.2–94 ng/L) were higher in the southwest of Cheju Island, while C37 alkenones (0–30 ng/L) were higher in the south of Cheju Island. In autumn, brassicasterol (12–106 ng/L), dinosterol (2.4–21 ng/L), and C37 alkenones (0.7–7.0 ng/L) were higher in the southwest of Cheju Island and the western Tsushima Strait, and higher C37 alkenones also occurred in the Okinawa Trough. Correlation analysis of biomarkers and environmental conditions (temperature, salinity, and inorganic nutrient concentrations) clearly demonstrated that phytoplankton biomass and community structure variations can be well elucidated by water masses as indexed by temperature and salinity. High nutrients from the Changjiang River were the main cause of high biomass in summer, while nutrients from subsurface water were likely the key factor regulating phytoplankton biomass in open ocean water stations in autumn. This study indicates that mechanisms controlling phytoplankton biomass in marginal sea‐open ocean boundary regions should be classified by various water masses with different nutrient concentrations, instead of by geography.
A Framework for Exploring Joint Effects of Conditional Factors on Compound Floods
Authors: Liu Zhiyong , Cheng Linyin , Hao Zengchao , Li Jingjing , Thorstensen Andrea , Gao Hongkai
Published: March 2018

This study highlights the features of vine copula for examining compound events involving underlying conditions that amply the compounding effects. To illustrate, we study compound floods in Texas (TX), USA. These compound floods consist of combinations of precipitation and surface runoff with the El Niño‐Southern Oscillation (ENSO) and rising temperatures as underlying conditions. Although the individual variable of precipitation and runoff may not itself be extreme, large exceedances can lead to flooding situations when combined. The presence of underlying conditions (e.g., El Niño and/or rising temperatures) can exacerbate the associated flood impacts. We use observational data during May–August for each climate division of TX. A three‐dimensional vine copula is used first to quantify the ENSO effect on precipitation and runoff through conditioning sets of vine copula. We further examine the interplay of a warming signal and El Niño to reveal their mutual effects on compound floods by placing these two factors as interrelated conditions in a four‐dimensional vine copula. Our results show that El Niño is much stronger than the other ENSO states in conditioning a high likelihood of TX compound floods by amplifying mean and extreme states of rainfall and runoff. Conditioned by both El Niño and global temperatures, a slight reduction occurs in TX compound floods under the warmer condition. This is consistent with the trend of precipitation and runoff composites under given conditions, while no appreciable changes are found to suggest a different joint effect of El Niño and rising temperatures on TX compound floods.
A Semianalytical Model for Pumping Tests in Finite Heterogeneous Confined Aquifers With Arbitrarily Shaped Boundary
Authors: Wang Lei , Dai Cheng , Xue Liang
Published: March 2018

This study presents a Laplace‐transform‐based boundary element method to model the groundwater flow in a heterogeneous confined finite aquifer with arbitrarily shaped boundaries. The boundary condition can be Dirichlet, Neumann or Robin‐type. The derived solution is analytical since it is obtained through the Green's function method within the domain. However, the numerical approximation is required on the boundaries, which essentially renders it a semi‐analytical solution. The proposed method can provide a general framework to derive solutions for zoned heterogeneous confined aquifers with arbitrarily shaped boundary. The requirement of the boundary element method presented here is that the Green function must exist for a specific PDE equation. In this study, the linear equations for the two‐zone and three‐zone confined aquifers with arbitrarily shaped boundary is established in Laplace space, and the solution can be obtained by using any linear solver. Stehfest inversion algorithm can be used to transform it back into time domain to obtain the transient solution. The presented solution is validated in the two‐zone cases by reducing the arbitrarily shaped boundaries to circular ones and comparing it with the solution in Lin et al. (2016, https://doi.org/10.1016/j.jhydrol.2016.07.028). The effect of boundary shape and well location on dimensionless drawdown in two‐zone aquifers is investigated. Finally the drawdown distribution in three‐zone aquifers with arbitrarily shaped boundary for constant‐rate tests (CRT) and flow rate distribution for constant‐head tests (CHT) are analyzed.
Improved Teleconnection‐Based Dynamical Seasonal Predictions of Boreal Winter
Authors: Dobrynin Mikhail , Domeisen Daniela I. V. , Müller Wolfgang A. , Bell Louisa , Brune Sebastian , Bunzel Felix , Düsterhus André , Fröhlich Kristina , Pohlmann Holger , Baehr Johanna
Published: March 2018

Climate and weather variability in the North Atlantic region is determined largely by the North Atlantic Oscillation (NAO). The potential for skillful seasonal forecasts of the winter NAO using an ensemble‐based dynamical prediction system has only recently been demonstrated. Here we show that the winter predictability can be significantly improved by refining a dynamical ensemble through subsampling. We enhance prediction skill of surface temperature, precipitation, and sea level pressure over essential parts of the Northern Hemisphere by retaining only the ensemble members whose NAO state is close to a “first guess” NAO prediction based on a statistical analysis of the initial autumn state of the ocean, sea ice, land, and stratosphere. The correlation coefficient between the reforecasted and observation‐based winter NAO is significantly increased from 0.49 to 0.83 over a reforecast period from 1982 to 2016, and from 0.42 to 0.86 for a forecast period from 2001 to 2017. Our novel approach represents a successful and robust alternative to further increasing the ensemble size, and potentially can be used in operational seasonal prediction systems.
Triggered Slow Slip and Afterslip on the Southern Hikurangi Subduction Zone Following the Kaikōura Earthquake
Authors: Wallace Laura M. , Hreinsdóttir Sigrún , Ellis Susan , Hamling Ian , D'Anastasio Elisabetta , Denys Paul
Published: March 2018

The 2016 MW7.8 Kaikōura earthquake ruptured a complex sequence of strike‐slip and reverse faults in New Zealand's northeastern South Island. In the months following the earthquake, time‐dependent inversions of Global Positioning System and interferometric synthetic aperture radar data reveal up to 0.5 m of afterslip on the subduction interface beneath the northern South Island underlying the crustal faults that ruptured in the earthquake. This is clear evidence that the far southern end of the Hikurangi subduction zone accommodates plate motion. The MW7.8 earthquake also triggered widespread slow slip over much of the subduction zone beneath the North Island. The triggered slow slip included immediate triggering of shallow (<15 km), short (2–3 weeks) slow slip events along much of the east coast, and deep (>30 km), long‐term (>1 year) slow slip beneath the southern North Island. The southern Hikurangi slow slip was likely triggered by large (0.5–1.0 MPa) static Coulomb stress increases.
Spatially Resolved Isotopic Source Signatures of Wetland Methane Emissions
Authors: Ganesan A. L. , Stell A. C. , Gedney N. , Comyn‐Platt E. , Hayman G. , Rigby M. , Poulter B. , Hornibrook E. R. C.
Published: March 2018

We present the first spatially resolved wetland δ13C(CH4) source signature map based on data characterizing wetland ecosystems and demonstrate good agreement with wetland signatures derived from atmospheric observations. The source signature map resolves a latitudinal difference of ~10‰ between northern high‐latitude (mean −67.8‰) and tropical (mean −56.7‰) wetlands and shows significant regional variations on top of the latitudinal gradient. We assess the errors in inverse modeling studies aiming to separate CH4 sources and sinks by comparing atmospheric δ13C(CH4) derived using our spatially resolved map against the common assumption of globally uniform wetland δ13C(CH4) signature. We find a larger interhemispheric gradient, a larger high‐latitude seasonal cycle, and smaller trend over the period 2000–2012. The implication is that erroneous CH4 fluxes would be derived to compensate for the biases imposed by not utilizing spatially resolved signatures for the largest source of CH4 emissions. These biases are significant when compared to the size of observed signals.
How the IMF By Induces a Local By Component During Northward IMF Bz and Characteristic Timescales
Authors: Tenfjord P. , Østgaard N. , Haaland S. , Snekvik K. , Laundal K. M. , Reistad J. P. , Strangeway R. , Milan S. E. , Hesse M. , Ohma A.
Published: March 2018

We use the Lyon‐Fedder‐Mobarry global magnetohydrodynamics model to study the effects of the interplanetary magnetic field (IMF) By component on the coupling between the solar wind and magnetosphere‐ionosphere system when IMF Bz>0. We describe the evolution of how a magnetospheric By component is induced on closed field lines during these conditions. Starting from dayside lobe reconnection, the magnetic tension on newly reconnected field lines redistribute the open flux asymmetrically between the two hemispheres. This results in asymmetric magnetic energy density in the lobes. Shear flows are induced to restore equilibrium, and these flows are what effectively induces a local By component. We show the radial dependence of the induced By and compare the results to the induced By during southward IMF conditions. We also show the response and reconfiguration time of the inner magnetosphere to IMF By reversals during northward IMF Bz . A superposed epoch analysis of magnetic field measurements from seven Geostationary Operational Environmental Satellite spacecraft at different local times both for negative‐to‐positive and positive‐to‐negative IMF By reversals is presented. We find that the induced By responds within 16 min of the arrival of IMF By at the bow shock, and it completely reconfigures within 47 min.
Constraining the Potential Liquid Water Environment at Gale Crater, Mars
Authors: Rivera‐Valentín Edgard G. , Gough Raina V. , Chevrier Vincent F. , Primm Katherine M. , Martínez German M. , Tolbert Margaret
Published: March 2018

The Mars Science Laboratory (MSL) Rover Environmental Monitoring Station (REMS) has now made continuous in situ meteorological measurements for several Martian years at Gale crater, Mars. Of importance in the search for liquid formation are REMS' measurements of ground temperature and in‐air measurements of temperature and relative humidity, which is with respect to ice. Such data can constrain the surface and subsurface stability of brines. Here we use updated calibrations to REMS data and consistent relative humidity comparisons (i.e., with respect to liquid versus with respect to ice) to investigate the potential formation of surface and subsurface liquids throughout MSL's traverse. We specifically study the potential for the deliquescence of calcium perchlorate. Our data analysis suggests that surface brine formation is not favored within the first 1648 sols as there are only two times (sols 1232 and 1311) when humidity‐temperature conditions were within error consistent with a liquid phase. On the other hand, modeling of the subsurface environment would support brine production in the shallow subsurface. Indeed, we find that the shallow subsurface for terrains with low thermal inertia (
 J m−2 K−1 s−1/2) may be occasionally favorable to brine formation through deliquescence. Terrains with
 J m−2 K−1 s−1/2 and albedos of
0.25 are the most apt to subsurface brine formation. Should brines form, they would occur around Ls 100°. Their predicted properties would not meet the Special nor Uncertain Region requirements, as such they would not be potential habitable environments to life as we know it.
Total Electron Content Retrieved From L‐Band Radiometers and Potential Improvements to the IGS Model
Authors: Soldo Yan , Hong Liang , El‐Nimri Salem , Le Vine David M.
Published: March 2018

In recent years, several L‐band microwave instruments have been launched into Earth's orbit to measure soil moisture and ocean salinity (e.g., Soil Moisture and Ocean Salinity [SMOS], Aquarius, and Soil Moisture Active/Passive [SMAP]). As the microwave signal travels through the ionosphere, the polarization vector rotates (Faraday rotation) and it is possible to estimate the total electron content (TEC) along the path by measuring this change. A comparison is presented of the TEC retrieved from Aquarius and SMAP over the ocean with the values provided by the IGS (International Global Navigation Satellite System Service (GNSS)). The TEC retrieved from Aquarius and SMAP measurements show good agreement with each other and, on a global scale, are in agreement with the TEC provided by the IGS. However, there are cases in which the TEC from the two satellite sensors are in good agreement with each other but differ significantly from the IGS TEC. The comparison suggests that the L‐band instruments are a reliable source of TEC over the ocean and could be a valuable supplementary source of TEC values that could be assimilated in the IGS models, especially over the ocean, where GNSS ground stations are sparse.
FGF‐2 suppresses expression of nephronectin via JNK and PI3K pathways
Authors: Kato Tadashi , Yamada Atsushi , Ikehata Mikiko , Yoshida Yuko , Sasa Kiyohito , Morimura Naoko , Sakashita Akiko , Iijima Takehiko , Chikazu Daichi , Ogata Hiroaki , Kamijo Ryutaro
Published: March 2018

Nephronectin (Npnt), an extracellular matrix protein, is a ligand for integrin α8β1 and is involved in the development of various organs, such as the kidneys, bones, liver, and muscles. Previously, we found that Npnt expression was inhibited by various cytokines including transforming growth factor‐β (Tgf‐β) and oncostatin M (Osm). Fibroblast growth factor (Fgf)‐2, otherwise known as basic Fgf, also plays important roles in skeletal development and postnatal osteogenesis. In this study, Npnt expression was found to be suppressed by Fgf‐2 in MC3T3‐E1 cells, an osteoblast‐like cell line, in a dose‐ and time‐dependent manners. Furthermore, Fgf‐2‐mediated NpntmRNA suppression was shown to involve the Jun N‐terminal kinase (JNK) and phosphoinositide‐3 kinase (PI3K) pathways. Together, our results suggest that FGF‐2 suppresses Npnt gene expression via JNK and PI3K pathways.
Studies on environmental perception during locomotion—a review of empirical studies by the Ohno laboratory
Authors: Ohno Ryuzo
Published: March 2018

Natural and man‐made landscapes cannot be seen all at once; they must be experienced in a temporal sequence. Most previous studies, however, discuss and evaluate landscapes in terms of static scenes facing the observer. As an attempt at the scientific investigation of the dynamic nature of perception during locomotion, this paper first discusses theoretical considerations on environmental perception and constructs a hypothetical model. It then presents a new research tool to describe and analyze both the continuous stream of sequential visual information received from the physical environment and the human response to it during locomotion. This is followed by a brief review of some of the major empirical studies conducted by the Ohno Laboratory at the Tokyo Institute of Technology. Experimental studies involving a Japanese garden, outdoor space at a university campus, and building exit areas generally support the model's validity and tools for environmental design.
Film‐based dose validation of Monte Carlo algorithm for Cyberknife system with a CIRS thorax phantom
Authors: Pan Yuxi , Yang Ruijie , Li Jun , Zhang Xile , Liu Lu , Wang Junjie
Published: March 2018

Monte Carlo (MC) simulation, as the most accurate dose calculation algorithm, is available in the MultiPlan treatment planning system for Cyberknife. The main purpose of this work was to perform experiments to thoroughly investigate the accuracy of the MC dose calculation algorithm. Besides the basic MC beam commissioning, two test scenarios were designed. First, single beam tests were performed with a solid water phantom to verify the MC source model in simple geometry. Then, a lung treatment plan on a CIRS thorax phantom was created to mimic the clinical patient treatment. The plan was optimized and calculated using ray tracing (RT) algorithm and then recalculated using MC algorithm. Measurements were performed in both a homogeneous phantom and a heterogeneous phantom (CIRS). Ion‐chamber and radiochromic film were used to obtain absolute point dose and dose distributions. Ion‐chamber results showed that the differences between measured and MC calculated dose were within 3% for all tests. On the film measurements, MC calculation results showed good agreements with the measured dose for all single beam tests. As for the lung case, the gamma passing rate between measured and MC calculated dose was 98.31% and 97.28% for homogeneous and heterogeneous situation, respectively, using 3%/2 mm criteria. However, RT algorithm failed with the passing rate of 79.25% (3%/2 mm) for heterogeneous situation. These results demonstrated that MC dose calculation algorithm in the Multiplan system is accurate enough for patient dose calculation. It is strongly recommended to use MC algorithm in heterogeneous media.
Rational Design of MXene/1T‐2H MoS2‐C Nanohybrids for High‐Performance Lithium–Sulfur Batteries
Authors: Zhang Yelong , Mu Zijie , Yang Chao , Xu Zhikun , Zhang Shan , Zhang Xiaoyan , Li Yingjie , Lai Jianping , Sun Zhonghui , Yang Yong , Chao Yuguang , Li Chunji , Ge Xiaoxiao , Yang Wenxiu , Guo Shaojun
Published: March 2018

Despite high‐energy density and low cost of the lithium–sulfur (Li–S) batteries, their commercial success is greatly impeded by their severe capacity decay during long‐term cycling caused by polysulfide shuttling. Herein, a new phase engineering strategy is demonstrated for making MXene/1T‐2H MoS2‐C nanohybrids for boosting the performance of Li–S batteries in terms of capacity, rate ability, and stability. It is found that the plentiful positively charged S‐vacancy defects created on MXene/1T‐2H MoS2‐C, proved by high‐resolution transmission electron microscopy and electron paramagnetic resonance, can serve as strong adsorption and activation sites for polar polysulfide intermediates, accelerate redox reactions, and prevent the dissolution of polysulfides. As a consequence, the novel MXene/1T‐2H MoS2‐C‐S cathode delivers a high initial capacity of 1194.7 mAh g−1 at 0.1 C, a high level of capacity retention of 799.3 mAh g−1 after 300 cycles at 0.5 C, and reliable operation in soft‐package batteries. The present MXene/1T‐2H MoS2‐C becomes among the best cathode materials for Li–S batteries.
Alkylsilyl Functionalized Copolymer Donor for Annealing‐Free High Performance Solar Cells with over 11% Efficiency: Crystallinity Induced Small Driving Force
Authors: Huang Bin , Chen Lie , Jin Xiufen , Chen Dong , An Yongkang , Xie Qian , Tan Yun , Lei Hui , Chen Yiwang
Published: March 2018

The contradiction between enlarging the offset between energy levels of donor/acceptor and the required driving force for exciton split leads to a trade‐off between open circuit voltage (VOC) and short circuit current density (JSC), which is a big challenge for development of high performance polymer solar cells (PSCs). Some advanced works reported the PSCs with low photon energy loss (Eloss) and small driving force, but the correlation of molecular structures of light‐harvesting system and driving force is still unclear. In this work, a new alkylsilyl functionalized copolymer donor PBDS‐T (PBDST: poly[(2,6trialkylsilyl thiophen2yl)benzo[1,2b:4,5b′]dithiophene))alt(5,5(1′,3′di2thienyl5′,7′bis(2ethylhexyl)benzo[1′,2′c:4′,5′c′]dithiophene4,8dione))]) with low‐lying energy levels was designed for efficient PSCs. By monitoring the Photoluminescence quenching of the bulk and bilayer heterojunctions, small driving forces, ∆EHOMO of 0.15 eV and ∆ELUMO of 0.22 eV were founded to allow for efficient charge transfer, which were observed to correlate with the crystalline PBDS‐T and the optimal morphology in PBDS‐T:ITIC (ITIC: 3,9bis(2methylene(3(1,1dicyanomethylene)indanone))5,5,11,11tetrakis(4hexylphenyl)dithieno[2,3d:2′,3′d′]sindaceno[1,2b:5,6b′]dithiophene). Simultaneously improved VOC, JSC and small Eloss boosted the PCE over 11%, which is one of the highest values for annealing‐free device. These results shield a light on precise design of a light‐harvesting system with small driving force to simultaneously improve the VOC and JSC for highly efficient PSCs.
Suspended SnS2 Layers by Light Assistance for Ultrasensitive Ammonia Detection at Room Temperature
Authors: Chen Huawei , Chen Yantao , Zhang Heng , Zhang David Wei , Zhou Peng , Huang Jia
Published: March 2018

2D materials are extensively studied as candidates for chemical sensors due to their large surface‐to‐volume‐ratio and the low working temperature. However, the performance of 2D material‐based sensors is limited when detecting ammonia, due to the weak binding between ammonia molecules and channel materials. Previous reports show sensitivity in the ppb range upon NO2 exposure, and in ppm levels of ammonia under the same conditions. Compared with the traditional SnS2 sensors, the demonstrated suspended devices with light excitation exhibit a higher sensitivity, a faster response, and recovery rate. At room temperature, the devices show obvious response to NH3 vapor at a concentration as low as 20 ppb. High selectivity to ammonia over many other chemical gases is observed. Such arresting features originate from the suspended structure enhancing reaction area and the light excitation inducing increased charge density that facilitates the ammonia detection. The enhanced sensing performance demonstrates the superiority of the suspended structure with light assistance, and this method can be applied to other 2D material‐based sensors on optimizing their performance.
Efficient Sodium Storage in Rolled‐Up Amorphous Si Nanomembranes
Authors: Huang Shaozhuan , Liu Lixiang , Zheng Yun , Wang Ye , Kong Dezhi , Zhang Yingmeng , Shi Yumeng , Zhang Lin , Schmidt Oliver. G. , Yang Hui Ying
Published: March 2018

Alloying‐type materials are promising anodes for high‐performance sodium‐ion batteries (SIBs) because of their high capacities and low Na‐ion insertion potentials. However, the typical candidates, such as P, Sn, Sb, and Pb, suffer from severe volume changes (≈293–487%) during the electrochemical reactions, leading to inferior cycling performances. Here, a high‐rate and ultrastable alloying‐type anode based on the rolled‐up amorphous Si nanomembranes is demonstrated. The rolled‐up amorphous Si nanomembranes show a very small volume change during the sodiation/desodiation processes and deliver an excellent rate capability and ultralong cycle life up to 2000 cycles with 85% capacity retention. The structural evolution and pseudocapacitance contribution are investigated by using the ex situ characterization techniques combined with kinetics analysis. Furthermore, the mechanism of efficient sodium‐ion storage in amorphous Si is kinetically analyzed through an illustrative atomic structure with dangling bonds, offering a new perspective on understanding the sodium storage behavior. These results suggest that nanostructured amorphous Si is a promising anode material for high‐performance SIBs.
Characterization of Atomic Structures of Nanosized Intermetallic Compounds Using Electron Diffraction Methods
Authors: Meshi Louisa , Samuha Shmuel
Published: March 2018

In metallurgy, many intermetallic compounds crystallize as nanosized particles in metallic matrices. These particles influence dramatically the physical properties of engineering materials such as alloys and steels. Since properties and crystal structure are intimately linked, characterization of the atomic model of these intermetallides is crucial for the development of new alloys. However, this structural information usually cannot be attained using traditional X‐ray diffraction methods, limited by the small volume and size of the precipitates. In these cases, electron diffraction (ED) is the most suitable method. In the last few decades, ED has experienced a tremendous leap forward. Many structures, including intermetallides, are solved using these methods. The class of intermetallides should be discussed independently since these phases do not comprise regular polyhedrals; moreover, the interatomic distances and angles vary drastically even in the same compositional system. These facts point to difficulties that have to be overcome during the solution path. Furthermore, intermetallic compounds can be of high complexity—possessing hundreds of atoms in the unit cell. Here, this topic is expanded with an emphasis on novel developments in the field.
Highly Efficient Spectrally Stable Red Perovskite Light‐Emitting Diodes
Authors: Tian Yu , Zhou Chenkun , Worku Michael , Wang Xi , Ling Yichuan , Gao Hanwei , Zhou Yan , Miao Yu , Guan Jingjiao , Ma Biwu
Published: March 2018

Perovskite light‐emitting diodes (LEDs) have recently attracted great research interest for their narrow emissions and solution processability. Remarkable progress has been achieved in green perovskite LEDs in recent years, but not blue or red ones. Here, highly efficient and spectrally stable red perovskite LEDs with quasi‐2D perovskite/poly(ethylene oxide) (PEO) composite thin films as the light‐emitting layer are reported. By controlling the molar ratios of organic salt (benzylammonium iodide) to inorganic salts (cesium iodide and lead iodide), luminescent quasi‐2D perovskite thin films are obtained with tunable emission colors from red to deep red. The perovskite/polymer composite approach enables quasi‐2D perovskite/PEO composite thin films to possess much higher photoluminescence quantum efficiencies and smoothness than their neat quasi‐2D perovskite counterparts. Electrically driven LEDs with emissions peaked at 638, 664, 680, and 690 nm have been fabricated to exhibit high brightness and external quantum efficiencies (EQEs). For instance, the perovskite LED with an emission peaked at 680 nm exhibits a brightness of 1392 cd m−2 and an EQE of 6.23%. Moreover, exceptional electroluminescence spectral stability under continuous device operation has been achieved for these red perovskite LEDs.
3D Printing of Bioinspired Liquid Superrepellent Structures
Authors: Liu Xiaojiang , Gu Hongcheng , Wang Min , Du Xin , Gao Bingbing , Elbaz Abdelrahman , Sun Liangdong , Liao Julong , Xiao Pengfeng , Gu Zhongze
Published: March 2018

Bioinspired re‐entrant structures have been proved to be effective in achieving liquid superrepellence (including anti‐penetration, anti‐adhesion, and anti‐spreading). However, except for a few reports relying on isotropic etching of silicon wafers, most fluorination‐dependent surfaces are still unable to repel liquids with extreme low surface energy (i.e., γ < 15 mN m−1), especially those fluorinated solvents. Herein, triply re‐entrant structures, possessing superrepellence to water (with surface tension γ of 72.8 mN m−1) and various organic liquids (γ = 12.0–27.1 mN m−1), are fabricated via two‐photon polymerization based 3D printing technology. Such structures can be constructed both on rigid and flexible substrates, and the liquid superrepellent properties can be kept even after oxygen plasma treatment. Based on the prepared triply re‐entrant structures, micro open capillaries are constructed on them to realize directional liquid spreading, which may be applied in microfluidic platforms and lab‐on‐a‐chip applications. The fabricated arrays can also find potential applications in electronic devices, gas sensors, microchemical/physical reactors, high‐throughput biological sensors, and optical displays.
Tetraphenylethylene‐Interweaving Conjugated Macrocycle Polymer Materials as Two‐Photon Fluorescence Sensors for Metal Ions and Organic Molecules
Authors: Li Xi , Li Zheng , Yang Ying‐Wei
Published: March 2018

A luminescent conjugated macrocycle polymer (CMP) with strong two‐photon fluorescence property, namely, P[5]‐TPE‐CMP, is constructed from ditriflate‐functionalized pillar[5]arene and a 1,1,2,2‐tetrakis(4‐ethynylphenyl)ethylene (TPE) linker through a Sonogashira–Hagihara cross‐coupling reaction. Significantly, in sharp contrast with the corresponding conjugated microporous polymer without synthetic macrocycles, P[5]‐TPE‐CMP shows an outstanding stability against photobleaching and exhibits highly selective cation sensing capability toward Fe3+ at different excitation wavelengths (both UV and red–near‐infrared regions). Meanwhile, its fluorescence could also be sufficiently quenched by 4‐amino azobenzene, a frequently used organic dye that is certified to be carcinogenic, as compared with a group of common organic compounds. This work paves a new way for enhancing the properties of porous organic polymers through the introduction of supramolecular macrocycles like macrocyclic arenes.
Diatomite‐Templated Synthesis of Freestanding 3D Graphdiyne for Energy Storage and Catalysis Application
Authors: Li Jiaqiang , Xu Jing , Xie Ziqian , Gao Xin , Zhou Jingyuan , Xiong Yan , Chen Changguo , Zhang Jin , Liu Zhongfan
Published: March 2018

Graphdiyne (GDY), a new kind of two‐dimensional (2D) carbon allotropes, has extraordinary electrical, mechanical, and optical properties, leading to advanced applications in the fields of energy storage, photocatalysis, electrochemical catalysis, and sensors. However, almost all reported methods require metallic copper as a substrate, which severely limits their large‐scale application because of the high cost and low specific surface area (SSA) of copper substrate. Here, freestanding three‐dimensional GDY (3DGDY) is successfully prepared using naturally abundant and inexpensive diatomite as template. In addition to the intrinsic properties of GDY, the fabricated 3DGDY exhibits a porous structure and high SSA that enable it to be directly used as a lithium‐ion battery anode material and a 3D scaffold to create Rh@3DGDY composites, which would hold great potential applications in energy storage and catalysts, respectively.
Macroscopic‐Oriented Gold Nanorods in Polyvinyl Alcohol Films for Polarization‐Dependent Multicolor Displays
Authors: Dai Liwei , Lu Xuefei , Song Liping , Huang Youju , Liu Baoqing , Zhang Lei , Zhang Jiawei , Wu Si , Chen Tao
Published: March 2018

Due to their abundant optical colors, durable color generation, and high refreshing rate, smart chromic nanomaterials (SCNMs) have been employed in various applications. However, most SCNMs often require multicomponent materials, precise morphology control, and complicated modulation to realize multicolor changes, which limits their widely practical applications. In the present study, a simple and effective strategy is demonstrated to achieve the flexible and cost‐effective multicolor gold nanorods (Au NRs)/polymer hybrid film, by tuning macroscopic‐oriented Au NRs in films and a synergy of polarization‐dependent surface plasmon resonance. Au NRs are first functionalized with methoxypoly(ethylene glycol)thiol to improve the compatibility, ensuring Au NRs can be homogenously dispersed in the polyvinyl alcohol (PVA) matrix with high particle density. The macroscopic‐oriented alignment of Au NRs can be achieved by the elongation of the PVA polymer molecular chains. Under different polarized excitation directions, the same strip of the hybrid film exhibits various colors including red, orange, yellow, and green. Therefore, the strategy provides a simple and powerful approach to achieve macroscopic‐oriented anisotropic nanoparticles in the polymer matrix, and the resultant hybrid films are promising in various practical applications, such as color displays, optical devices, and plasmonic biosensors.
Biomimetic Surface Engineering of Biomaterials by Using Recombinant Mussel Adhesive Proteins
Authors: Jo Yun Kee , Kim Hyo Jeong , Jeong Yeonsu , Joo Kye Il , Cha Hyung Joon
Published: March 2018

Surface engineering is a key approach for tailoring new functionalities into biomaterials to achieve better clinical performance. The rise of genetic engineering and molecular biotechnology made it possible to design artificial sticky proteins derived from marine mussels that are capable of firmly anchoring on a variety of substrates with high binding strength, opening a new route for surface engineering of biomaterials. Coatings of recombinant mussel adhesive proteins (MAPs) have aroused great interest for the surface functionalization of biomaterials due to their simplicity, versatility, and high stability under physiological conditions, as well as their favorable interactions with cells. In addition, recombinant MAPs can be engineered to provide desired specific functionalities on target surfaces by genetic fusion with functional peptides and/or by the immobilization of biomolecules. This review provides an overview of recombinant MAPs‐based surface coatings, highlighting their mechanisms, characteristic surface properties, and diverse applications in providing bioengineered surfaces in the fields of biomedical and tissue engineering.
Integrated Optical Amplifier–Photodetector on a Wearable Nanocellulose Substrate
Authors: Suárez Isaac , Hassanabadi Ehsan , Maulu Alberto , Carlino Niccolò , Maestri Cecilia Ada , Latifi Masoud , Bettotti Paolo , Mora‐Seró Iván , Martínez‐Pastor Juan P.
Published: March 2018

Flexible optoelectronics has emerged as an outstanding platform to pave the road toward vanguard technology advancements. As compared to conventional rigid substrates, a flexible technology enables mechanical deformation while maintaining stable performance. The advantages include not only the development to novel applications, but also the implementation of a wearable technology directly in contact with a curved surface. Here the monolithic integration of a perovskite‐based optical waveguide amplifier together with a photodetector on a nanocellulose substrate is shown to demonstrate the feasibility of a stretchable signal manipulation and receptor system fabricated on a biodegradable material. An integrated optical amplifier–photodetector is developed in which the photocurrent is exploited that is generated in the organic–inorganic lead halide perovskite under an applied bias. Such photocurrent does not minimally perturb the amplifier operation and is used to monitor the light signal propagating along the waveguide, opening a broad range of applications for example to regulate the operation temperature.
Laminated Hybrid Junction of Sulfur‐Doped TiO2 and a Carbon Substrate Derived from Ti3C2 MXenes: Toward Highly Visible Light‐Driven Photocatalytic Hydrogen Evolution
Authors: Yuan Wenyu , Cheng Laifei , An Yurong , Lv Shilin , Wu Heng , Fan Xiaoli , Zhang Yani , Guo Xiaohui , Tang Junwang
Published: March 2018

TiO2 is an ideal photocatalyst candidate except for its large bandgap and fast charge recombination. A novel laminated junction composed of defect‐controlled and sulfur‐doped TiO2 with carbon substrate (LDC‐S‐TiO2/C) is synthesized using the 2D transition metal carbides (MXenes) as a template to enhance light absorption and improve charge separation. The prepared LDC‐S‐TiO2/C catalyst delivers a high photocatalytic H2 evolution rate of 333 µmol g−1 h−1 with a high apparent quantum yield of 7.36% at 400 nm and it is also active even at 600 nm, resulting into a 48 time activity compared with L‐TiO2/C under visible light irradiation. Further theoretical modeling calculation indicates that such novel approach also reduces activation energy of hydrogen production apart from broadening the absorption wavelength, facilitating charge separation, and creating a large surface area substrate. This synergic effect can also be applied to other photocatalysts' modification. The study provides a novel approach for synthesis defective metal oxides based hybrids and broaden the applications of MXene family.
High Voltage Operation of Ni‐Rich NMC Cathodes Enabled by Stable Electrode/Electrolyte Interphases
Authors: Zhao Wengao , Zheng Jianming , Zou Lianfeng , Jia Haiping , Liu Bin , Wang Hui , Engelhard Mark H. , Wang Chongmin , Xu Wu , Yang Yong , Zhang Ji‐Guang
Published: March 2018

The lithium (Li) metal battery (LMB) is one of the most promising candidates for next‐generation energy storage systems. However, it is still a significant challenge to operate LMBs with high voltage cathodes under high rate conditions. In this work, an LMB using a nickel‐rich layered cathode of LiNi0.76Mn0.14Co0.10O2 (NMC76) and an optimized electrolyte [0.6 m lithium bis(trifluoromethanesulfonyl)imide + 0.4 m lithium bis(oxalato)borate + 0.05 m LiPF6 dissolved in ethylene carbonate and ethyl methyl carbonate (4:6 by weight)] demonstrates excellent stability at a high charge cutoff voltage of 4.5 V. Remarkably, these Li||NMC76 cells can deliver a high discharge capacity of >220 mA h g−1 (846 W h kg−1) and retain more than 80% capacity after 1000 cycles at high charge/discharge current rates of 2C/2C (1C = 200 mA g−1). This excellent electrochemical performance can be attributed to the greatly enhanced structural/interfacial stability of both the Ni‐rich NMC76 cathode material and the Li metal anode using the optimized electrolyte.
Characteristics of hyperuricemia in older adults in China and possible associations with sarcopenia
Authors: Xu Zhe‐rong , Zhang Qin , Chen Lu‐fang , Xu Ke‐ying , Xia Jia‐ying , Li Shu‐min , Yang Yun‐mei
Published: March 2018

Objective

This cross‐sectional study aimed to investigate the characteristics and epidemiology of hyperuricemia in older adults in China and evaluate possible associations between hyperuricemia and sarcopenia.

Methods

Three hundred and eighty‐eight study subjects (>60 years old) meeting the inclusion criteria received blood tests and standardized examinations for bone mineral density, muscle mass, muscle strength, and physical performance. Data including demographic and clinical characteristic and comorbidity were also collected. All data were analyzed retrospectively.

Results

In the study population, higher uric acid levels were significantly correlated with higher muscle mass, grip strength, and bone density, but were unrelated to physical performance. When uric acid levels were separated into quartiles and the population was divided by sex, the correlation of uric acid to muscle mass was retained in some quartiles for both men and women, and the correlation to handgrip was only retained for one quartile for men. The correlation to bone density was retained in women in all analyses.

Conclusion

In the population as a whole, higher uric acid levels were significantly correlated with higher muscle mass, grip strength, and bone density, but had no relationship to physical performance. Differences between men and women in these relationships need to be studied further.
On the steady‐state drop size distribution in stirred vessels. Part I: Effect of dispersed phase viscosity
Authors: Carrillo De Hert Sergio , Rodgers Thomas L.
Published: March 2018

Previous studies on emulsification have used the maximum drop size (dmax) or Sauter mean diameter (
) to investigate the effect of viscosity on the drop size distribution (DSD), however, these parameters fall short for highly polydispersed emulsions. In this investigation (Part I), the steady‐state DSD of dilute emulsions is studied using of silicon oils with viscosities varying across six orders of magnitude at different stirring speeds. Different emulsification regimes were identified; our modeling and analysis is centered on the intermediate viscosity range where interfacial cohesive stresses can be considered negligible and drop size increases with viscosity. The bimodal frequency distributions by volume were well described using two log‐normal density functions. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3293–3302, 2018
Transfusion‐related adverse events are decreased in pregnant women with sickle cell disease by a change in policy from systematic transfusion to prophylactic oxygen therapy at home: A retrospective survey by the international sickle cell disease observatory
Authors: Ribeil Jean‐Antoine , Labopin Myriam , Stanislas Aurélie , Deloison Benjamin , Lemercier Delphine , Habibi Anoosha , Albinni Souha , Charlier Caroline , Lortholary Olivier , Lefrere François , De Montalembert Mariane , Blanche Stéphane , Galactéros Frédéric , Tréluyer Jean‐Marc , Gluckman Eliane , Ville Yves , Joseph Laure , Delville Marianne , Benachi Alexandra , Cavazzana Marina
Published: March 2018

Sickle cell disease (SCD) in pregnancy can be associated with adverse maternal and perinatal outcomes. Furthermore, complications of SCD can be aggravated by pregnancy. Optimal prenatal care aims to decrease the occurrence of maternal and fetal complications. A retrospective, French, two‐center study compared two care strategies for pregnant women with SCD over two time periods. In the first study period (2005‐2010), the women were systematically offered prophylactic transfusions. In the second study period (2011‐2014), a targeted transfusion strategy was applied whenever possible, and home‐based prophylactic nocturnal oxygen therapy was offered to all the pregnant women. The two periods did not differ significantly in terms of the incidence of vaso‐occlusive events. Maternal mortality, perinatal mortality, and obstetric complication rates were also similar in the two periods, as was the incidence of post‐transfusion complications (6.1% in 2005‐2010 and 1.3% in 2011‐2014, P = .15), although no de novo alloimmunizations or delayed hemolysis transfusion reactions were observed in the second period. The results of this preliminary, retrospective study indicate that targeted transfusion plus home‐based prophylactic nocturnal oxygen therapy is safe and may decrease transfusion requirements and transfusion‐associated complications.