bluuebunny/crossref_metadata_2025 huggingface dataset:
THE BEGINNINGS OF REINFORCED CONCRETE IN SPAIN: FRANCISCO URCOLA AND THREE REMARKABLE BUILDINGS
Authors: CARRASCO ANDRES FIDEL , CARRASCO ANDRES JULIO , DEL CASTILLO RODRIGUEZ CARMEN
Published: February 2018

The origins of reinforced concrete en Spain were based on the system of patents, coming from countries o our environment, mainly European. The first patent to be approved was that of the French Joseph Monier in 1884. These documents defined generic schemes of metallic reinforcements, which architects, engineers and builders adapted to their works based on their experience. In this environment the figure of Francisco Urcola Lazcanotegui, a poorly known Donostia architect, although he projected some very important buildings of thoseyears, such as the Hotel Maria Cristina and the Teatro Victoria Eugenia de San Sebastian. This article focuses on entertainment buildings, given their special commitment to the occasional occupation of large numbers of spectators, which subjects structures to stress states higher than those of conventional buildings, such as housing. In Urcola's work, besides the aforementioned theater, the monumental bullrings of Seville and Pamplona are two important buildings.

Keywords: concrete, Urcola, San Sebastián, Sevilla, Pamplona
INFLUENCES OF SUBWAY TUNNELING ON DISASTER OF OVERLYING RAINWATER AND SEWAGE PIPELINES
Authors: HU YU , YAO AIJUN , ZHANG JIANTAO , GUO HAIGENG
Published: February 2018

Tunneling can cause the disaster of surrounding pipelines, thereby inducing serious consequences, such as road collapse. Existing relevant studies mainly focus on small-diameter pressure pipelines, while explorations on disaster characteristics of large-diameter overlying rainwater and sewage pipelines (ORSP) with high rigidity and strength as well as socket are rare, and the research methods of disaster characteristics of small-diameter pressure pipelines are mostly a combination of theoretical and experimental analyses, or a combination of theoretical and finite element analyses. In order to study the disaster characteristics of large-diameter ORSP during tunneling, the settlement and stress features of pipelines were evaluated through a model experiment of the pipe-tunnel orthogonal program, and influences of tunneling on the disaster of ORSP were discussed. Then, nonlinear simulation of the model was performed by finite element analysis. Numerical results are compared with model experiment and theoretical calculation results, and main indexes that influence the disaster characteristics of ORSP were examined. The results demonstrate that the settlement curve of ORSP conforms to Gaussian distribution, and the height of subsider increases with the increase in excavation procedures and stabilization time, thereby reaching 19.5 mm. Stress on ORSP is symmetric around tunnel centerline. The bottom is pressed slightly, while the top is stretched locally. Reliability of numerical model and theoretical calculation is validated by the finite element analysis. Stress ranges between ?545-59kPa, indicating that most positions of top and bottom of ORSP bear low pressures. The settlement of ORSP according to parameter analysis decreases with the increase in pipe-tunnel net distance (l) and inner diameter of pipeline (d). The settlement of ORSP becomes stable When l/D>3 (D is tunnel diameter) and d/l>0.24. The stress of ORSP gradually decreases with the growth of l and d. Conclusions in this study can provide theoretical references for ORSP protection measures in subway tunnel constructions.

Keywords: pipelines, model experiment, finite element, disaster characteristics, validate
MAGNETITE AS ENVIRONMENTAL POLLUTION AND ITS INCIDENCE ON SMARTPHONES
Authors: TORRES SILVA HECTOR
Published: February 2018

Environmental pollution is a global problem that puts the health of the population at risk. Large metropolises such as Mexico City, Lima, Santiago de Chile in Latin America and European cities such as Madrid in cold weather are affected by the appearance of so-called pollution berets, activating the respective anti-pollution protocols. PM 2.5 particulate pollutants (particles smaller than 2.5 microns)-smaller particles are the most harmful, as they can penetrate directly into the lungs and brain. A latent and little studied danger is the influence of magnetite generated in vehicle combustion as a 2.5-10 micron particulate matter deposited in the brain.

Translated with www.DeepL.com/Translator
PRODUCTION PROGRAMMING IN REPETITIVE ENVIRONMENTS WITH ERGONOMIC RESTRICTIONS
Authors: ASENSIO CUESTA SABINA , GOMEZ GASQUET PEDRO
Published: February 2018

In the manufacturing industry it is common to find work activities where workers are subjected to excessively repetitive movements, being this one of the risk factors most commonly linked to musculoskeletal disorders (MSD). Lack of "recovery periods" increases muscle fatigue and therefore increases the likelihood of workers suffering from MSD (Colombini et al. 2002). Various ergonomic assessment methods are currently used to determine the level of risk to which workers are exposed when performing repetitive movements. In this proposal, the OCRA (Occupational Repetitive Actions) method has been chosen (Colombini et al., 2002). The OCRA method is included in the UNE-EN 1005-5:2007 and ISO 11228-3:2007 standards.
Benthic macrofaunal structure and secondary production in tropical estuaries on the Eastern Marine Ecoregion of Brazil
Authors: Bissoli Lorena B. , Bernardino Angelo F.
Published: February 2018

Tropical estuaries are highly productive and support diverse benthic assemblages within mangroves and tidal flats habitats. Determining differences and similarities of benthic assemblages within estuarine habitats and between regional ecosystems may provide scientific support for management of those ecosystems. Here we studied three tropical estuaries in the Eastern Marine Ecoregion of Brazil to assess the spatial variability of benthic assemblages from vegetated (mangroves) and unvegetated (tidal flats) habitats. A nested sampling design was used to determine spatial scales of variability in benthic macrofaunal density, biomass and secondary production. Habitat differences in benthic assemblage composition were evident, with mangrove forests being dominated by annelids (Oligochaeta and Capitellidae) whereas peracarid crustaceans were also abundant on tidal flats. Macrofaunal biomass, density and secondary production also differed between habitats and among estuaries. Those differences were related both to the composition of benthic assemblages and to random spatial variability, underscoring the importance of hierarchical sampling in estuarine ecological studies. Given variable levels of human impacts and predicted climate change effects on tropical estuarine assemblages in Eastern Brazil, our data support the use of benthic secondary production to address long-term changes and improved management of estuaries in Eastern Brazil.
Investigating the molecular basis for heterophylly in the aquatic plantPotamogeton octandrus(Potamogetonaceae) with comparative transcriptomics
Authors: He Dingxuan , Guo Pin , Gugger Paul F. , Guo Youhao , Liu Xing , Chen Jinming
Published: February 2018

Many plant species exhibit different leaf morphologies within a single plant, or heterophylly. The molecular mechanisms regulating this phenomenon, however, have remained elusive. In this study, the transcriptomes of submerged and floating leaves of an aquatic heterophyllous plant,Potamogeton octandrusPoir, at different stages of development, were sequenced using high-throughput sequencing (RNA-Seq), in order to aid gene discovery and functional studies of genes involved in heterophylly. A total of 81,103 unigenes were identified in submerged and floating leaves and 6,822 differentially expressed genes (DEGs) were identified by comparing samples at differing time points of development. KEGG pathway enrichment analysis categorized these unigenes into 128 pathways. A total of 24,025 differentially expressed genes were involved in carbon metabolic pathways, biosynthesis of amino acids, ribosomal processes, and plant-pathogen interactions. In particular, KEGG pathway enrichment analysis categorized a total of 70 DEGs into plant hormone signal transduction pathways. The high-throughput transcriptomic results presented here highlight the potential for understanding the molecular mechanisms underlying heterophylly, which is still poorly understood. Further, these data provide a framework to better understand heterophyllous leaf development in P. octandrus via targeted studies utilizing gene cloning and functional analyses.
Методы и проблемы оценки цунамиопасности морских побережий, "Фундаментальная и прикладная гидрофизика"
Authors: Гусяков В.К.
Published: February 2018

Обсуждаются методы и подходы, используемые в России и за рубежом для картирования цунамиопасности на побережьях, подверженных воздействию волн цунами, т. е. для решения задачи предварительного цунамирайо- нирования побережья. Эта задача состоит в получении оценок высот цунами на берегу с заданной вероятностью превышения в течении определенного интервала времени. В настоящее время она решается на основе построения сейсмотектонических моделей основных цунамигенных зон, угрожающих данному побережью и применения численных моделей возбуждения и распространения цунами в океане с реальным рельефом дна для получения расчетного каталога высот волн на побережье. Отмечается методологическая общность этой задачи с задачей оценки сейсмоопасности прибрежных территорий, которая во всех странах сейчас решается на основе методики Probabilistic Seismic Hazard Assessment. Применительно к задаче цунамирайонирования подобная методика получила название Probabilistic Tsunami Hazard Assessment. При всех известных недостатках этой методики, как принципиальных, так и технических, она может и должна быть использована для картирования цунамиопасности на побережьях России. Обсуждаются подходы к рациональному выбору масштабов карт цунамиопасности, к определению набора картируемых параметров, проблема оценки максимально возможного события.
Воздействие волн цунами на побережье и сооружения, "Фундаментальная и прикладная гидрофизика"
Authors: Гюлер Х. , Чинар Г. , Шаргхиванд Н. , Создинлер Д. , Доган Г. , Немиоглу О. , Зайцев А. , Ялчинер А.
Published: February 2018

Цунами оказывает высокое воздействие, приводит к долгосрочным бедствиям, о которых в большинстве случаев возможно заранее дать предупреждение только за несколько минут. Количество энергии после прохождения огромных волн цунами может вызвать серьезное разрушение, когда это поражает землю и следовательно вызывает крупные человеческие жертвы. Воздействие цунами можно рассмотреть в социальных, экологических и экономических аспектах. Социальное воздействие может быть рассмотрено в разрушении жизни и собственности, эпиди- мическом кризисе и заболеваниях. Цунами может вызвать крупное экологическое воздействие разрушительными эффектами. В данной статье воздействие цунами 2004 и 2011 гг. на побережья и сооружения оценено с инженерной точки зрения. Представлены обсуждения и даны предложения. Надежный и обоснованный план уменьшения воздействия цунами должен быть разработан в прибрежных районах. В развитии этого плана и системы прогноза должны быть учтены структурные и неструктурные меры. Проблему цунами необходимо учитывать во время любого строительства, необходимо применять стойкие к землетрясению структуры, дамбы, волнорезы, а также строения для эвакуации. Также необходимо применять неструктурные меры, например законы о планировании землепользования, обучение и образование, чтобы повысить осведомленность общественности
The Dependence of the Peak Velocity of High‐Speed Solar Wind Streams as Measured in the Ecliptic by ACE and the STEREO satellites on the Area and Co‐latitude of Their Solar Source Coronal Holes
Authors: Hofmeister Stefan J. , Veronig Astrid , Temmer Manuela , Vennerstrom Susanne , Heber Bernd , Vršnak Bojan
Published: February 2018

We study the properties of 115 coronal holes in the time range from August 2010 to March 2017, the peak velocities of the corresponding high‐speed streams as measured in the ecliptic at 1 AU, and the corresponding changes of the Kp index as marker of their geoeffectiveness. We find that the peak velocities of high‐speed streams depend strongly on both the areas and the co‐latitudes of their solar source coronal holes with regard to the heliospheric latitude of the satellites. Therefore, the co‐latitude of their source coronal hole is an important parameter for the prediction of the high‐speed stream properties near the Earth. We derive the largest solar wind peak velocities normalized to the coronal hole areas for coronal holes located near the solar equator and that they linearly decrease with increasing latitudes of the coronal holes. For coronal holes located at latitudes
60°, they turn statistically to zero, indicating that the associated high‐speed streams have a high chance to miss the Earth. Similarly, the Kp index per coronal hole area is highest for the coronal holes located near the solar equator and strongly decreases with increasing latitudes of the coronal holes. We interpret these results as an effect of the three‐dimensional propagation of high‐speed streams in the heliosphere; that is, high‐speed streams arising from coronal holes near the solar equator propagate in direction toward and directly hit the Earth, whereas solar wind streams arising from coronal holes at higher solar latitudes only graze or even miss the Earth.
Formation of Butterfly Pitch Angle Distributions of Relativistic Electrons in the Outer Radiation Belt With a Monochromatic Pc5 Wave
Authors: Kamiya K. , Seki K. , Saito S. , Amano T. , Miyoshi Y.
Published: February 2018

Radial transport of relativistic electrons in the inner magnetosphere has been considered one of the acceleration mechanisms of the outer radiation belt electrons and can be driven by the drift resonance with Pc5 ultralow‐frequency waves. In this study, we focus on the pitch angle dependences of the radial transport and investigate the pitch angle distributions (PADs) of the relativistic electrons after interaction with a monochromatic Pc5 wave, using two simulation models of the inner magnetosphere: Geomagnetic Environment Modeling System for Integrated Studies (GEMSIS)‐Ring Current and GEMSIS‐Radiation Belt models. The results show that butterfly‐like PADs (two peaks in small pitch angles) are produced at a fixed radial distance (L‐shell) and energy, where the electrons with small pitch angles satisfy the resonance condition. The radial range and timescale of the butterfly PAD appearance correspond to the maximum radial transport of the electron (i.e., resonant width) and its oscillation period in the radial direction, respectively. We analytically derive the resonant width and oscillation period of relativistic electrons interacting with a monochromatic Pc5 wave, assuming conservation of first and second adiabatic invariants, and compare them with the simulation result. The results show that electrons with small equatorial pitch angles at a fixed magnetic moment can interact with a monochromatic Pc5 wave in a wider L‐shell range than perpendicular electrons due to the pitch angle changes, in the course of the radial transport.
Large‐Amplitude High‐Frequency Waves at Earth's Magnetopause
Authors: Graham D. B. , Vaivads A. , Khotyaintsev Yu. V. , André M. , Le Contel O. , Malaspina D. M. , Lindqvist P.‐A. , Wilder F. D. , Ergun R. E. , Gershman D. J. , Giles B. L. , Magnes W. , Russell C. T. , Burch J. L. , Torbert R. B.
Published: February 2018

Large‐amplitude waves near the electron plasma frequency are found by the Magnetospheric Multiscale (MMS) mission near Earth's magnetopause. The waves are identified as Langmuir and upper hybrid (UH) waves, with wave vectors either close to parallel or close to perpendicular to the background magnetic field. The waves are found all along the magnetopause equatorial plane, including both flanks and close to the subsolar point. The waves reach very large amplitudes, up to 1 V m−1, and are thus among the most intense electric fields observed at Earth's magnetopause. In the magnetosphere and on the magnetospheric side of the magnetopause the waves are predominantly UH waves although Langmuir waves are also found. When the plasma is very weakly magnetized only Langmuir waves are likely to be found. Both Langmuir and UH waves are shown to have electromagnetic components, which are consistent with predictions from kinetic wave theory. These results show that the magnetopause and magnetosphere are often unstable to intense wave activity near the electron plasma frequency. These waves provide a possible source of radio emission at the magnetopause.
Constraints on North Anatolian Fault Zone Width in the Crust and Upper Mantle From S Wave Teleseismic Tomography
Authors: Papaleo E. , Cornwell D. , Rawlinson N.
Published: February 2018

We present high‐resolution S wave teleseismic tomography images of the western segment of the North Anatolian Fault Zone (NAFZ) in Turkey using teleseismic data recorded during the deployment period of the Dense Array for Northern Anatolia array. The array comprised 66 stations with a nominal station spacing of 7 km, thus permitting a horizontal and vertical resolution of approximately 15 km. We use the current S wave results with previously published P wave teleseismic tomography to produce maps of relative VP/VS anomalies, which we use to highlight the difference in overall composition of the three terranes separated by the northern (NNAF) and southern branches of the NAFZ. Our results show a narrow S wave low‐velocity anomaly beneath the northern branch of the NAFZ extending from the upper crust, where it has a width of ∼10 km, to the lower crust, where it widens to ∼30 km. This low‐velocity zone most likely extends into the upper mantle, where we constrain its width to be ≤ 50 km and interpret it as indicative of localized shear beneath the NNAF; this structure is similar to what has been observed for the NAFZ west of 32°, and therefore, we propose that the structure of the NNAF is similar to that of the NAFZ in the east. The southern branch of the NAFZ does not show a very strong signature in our images, and we conclude that it is most likely rooted in the crust, possibly accommodating deformation related to rotation of the Armutlu/Almacik Blocks situated between the two NAFZ branches.
Photogravitactic Microswimmers
Authors: Singh Dhruv P. , Uspal William E. , Popescu Mihail N. , Wilson Laurence G. , Fischer Peer
Published: February 2018

Phototactic microorganisms are commonly observed to respond to natural sunlight by swimming upward against gravity. This study demonstrates that synthetic photochemically active microswimmers can also swim against gravity. The particles initially sediment and, when illuminated at low light intensities exhibit wall‐bound states of motion near the bottom surface. Upon increasing the intensity of light, the artificial swimmers lift off from the wall and swim against gravity and away from the light source. This motion in the bulk has been further confirmed using holographic microscopy. A theoretical model is presented within the framework of self‐diffusiophoresis, which allows to unequivocally identify the photochemical activity and the phototactic response as key mechanisms in the observed phenomenology. Since the lift‐off threshold intensity depends on the particle size, it can be exploited to selectively address particles with the same density from a polydisperse mixture of active particles and move them in or out of the boundary region. This study provides a simple design strategy to fabricate artificial microswimmers whose two‐ or three‐dimensional swimming behavior can be controlled with light.
Localized Surface Plasmon Enhanced All‐Inorganic Perovskite Quantum Dot Light‐Emitting Diodes Based on Coaxial Core/Shell Heterojunction Architecture
Authors: Shi Zhifeng , Li Ying , Li Sen , Li Xinjian , Wu Di , Xu Tingting , Tian Yongtao , Chen Yongsheng , Zhang Yuantao , Zhang Baolin , Shan Chongxin , Du Guotong
Published: February 2018

This work presents a strategy of combining the concepts of localized surface plasmons (LSPs) and core/shell nanostructure configuration in a single perovskite light‐emitting diode (PeLED) to addresses simultaneously the emission efficiency and stability issues facing current PeLEDs' challenges. Wide bandgap n‐ZnO nanowires and p‐NiO are employed as the carrier injectors, and also the bottom/upper protection layers to construct coaxial core/shell heterostructured CsPbBr3 quantum dots LEDs. Through embedding plasmonic Au nanoparticles into the device and thickness optimization of the MgZnO spacer layer, an emission enhancement ratio of 1.55 is achieved. The best‐performing plasmonic PeLED reaches up a luminance of 10 206 cd m−2, an external quantum efficiency of ≈4.626%, and a current efficiency of 8.736 cd A−1. The underlying mechanisms for electroluminescence enhancement are associated with the increased spontaneous emission rate and improved internal quantum efficiency induced by exciton–LSP coupling. More importantly, the proposed PeLEDs, even without encapsulation, present a substantially improved operation stability against water and oxygen degradation (30‐day storage in air ambient, 85% humidity) compared with any previous reports. It is believed that the experimental results obtained will provide an effective strategy to enhance the performance of PeLEDs, which may push forward the application of such kind of LEDs.
A Solar Transistor and Photoferroelectric Memory
Authors: Pérez‐Tomás Amador , Lima Anderson , Billon Quentin , Shirley Ian , Catalan Gustau , Lira‐Cantú Mónica
Published: February 2018

This study presents a new self‐powered electronic transistor concept “the solar transistor.” The transistor effect is enabled by the functional integration of a ferroelectric‐oxide thin film and an organic bulk heterojunction. The organic heterojunction efficiently harvests photon energy and splits photogenerated excitons into free electron and holes, and the ferroelectric film acts as a switchable electron transport layer with tuneable conduction band offsets that depend on its polarization state. This results in the device photoconductivity modulation. All this (i.e., carrier extraction and poling) is achieved with only two sandwiched electrodes and therefore, with the role of the gating electrode being taken by light. The two‐terminal solar‐powered phototransistor (or solaristor) thus has the added advantages of a compact photodiode architecture in addition to the nonvolatile functionality of a ferroelectric memory that is written by voltage and nondestructively read by light.
Rapid Detection of the Biomarkers for Carcinoid Tumors by a Water Stable Luminescent Lanthanide Metal–Organic Framework Sensor
Authors: Wu Shuangyan , Lin Yanna , Liu Jingwei , Shi Wei , Yang Guangming , Cheng Peng
Published: February 2018

Serotonin (5‐hydroxytryptamine, HT), a neurotransmitter, and its main metabolite 5‐hydroxyindole‐3‐acetic acid (HIAA) are biomarkers for carcinoid tumors. They can be quantitatively detected by a new luminescent sensor based on a water stable lanthanide metal–organic framework (Ln‐MOF). This Ln‐MOF features a (3,4)‐connected topology containing 1D channels occupied by lattice water molecules. Luminescent studies reveal that high luminescence quenching efficiency occurs upon the addition of HT and HIAA. The Ln‐MOF also displays excellent sensitivity with fast response within 1 min, good reusability, and detection limits as low as 0.66 and 0.54 × 10−6m for HT and HIAA, respectively. In addition, the sensing function exhibits excellent selectivity even in the presence of other neurotransmitters and the main coexisting species in blood plasma and urine.
Highly Efficient Circularly Polarized Electroluminescence from Aggregation‐Induced Emission Luminogens with Amplified Chirality and Delayed Fluorescence
Authors: Song Fengyan , Xu Zeng , Zhang Qiushuo , Zhao Zheng , Zhang Haoke , Zhao Weijun , Qiu Zijie , Qi Chunxuan , Zhang Han , Sung Herman H. Y. , Williams Ian D. , Lam Jacky W. Y. , Zhao Zujin , Qin Anjun , Ma Dongge , Tang Ben Zhong
Published: February 2018

Development of highly efficient circularly polarized organic light‐emitting diodes (CPOLEDs) has gained increasing interest as they show improved luminous efficiency and high contract 3D images in OLED displays. In this work, a series of binaphthalene‐containing luminogenic enantiomers with aggregation‐induced emission (AIE) and delayed fluorescence properties is designed and synthesized. These molecules can emit from green to red light depending on the solvent polarity due to the twisted intramolecular charge transfer effect. However, their solid powders show bright light emissions, demonstrating a phenomenon of AIE. All the molecules exhibit Cotton effects and circularly polarized luminescence in toluene solution and films. Multilayer CPOLEDs using the doped and neat films of the molecules as emitting layers are fabricated, which exhibit high external quantum efficiency of up to 9.3% and 3.5% and electroluminescence dissymmetry factor (gEL) of up to +0.026/−0.021 and +0.06/−0.06, respectively. Compared with doped CPOLEDs, the nondoped ones show higher gEL and much smaller current efficiency roll‐off due to the stronger AIE effect. By altering the donor unit, the electroluminescence maximum of the doped film can vary from 493 to 571 nm. As far as it is known, this is the first example of efficient CPOLEDs based on small chiral organic molecules.
In Situ Polymerization of Nanostructured Conductive Polymer on 3D Sulfur/Carbon Nanofiber Composite Network as Cathode for High‐Performance Lithium–Sulfur Batteries
Authors: Zhu Pei , Zhu Jiadeng , Yan Chaoyi , Dirican Mahmut , Zang Jun , Jia Hao , Li Ya , Kiyak Yasar , Tan Hongsheng , Zhang Xiangwu
Published: February 2018

Lithium–sulfur (Li‐S) batteries have been considered as a promising next‐generation energy storage system. However, practical application of Li‐S batteries is hindered by the nonconductive nature of sulfur (S) and continuous capacity fading during cycling. Here, a simple but effective strategy is proposed to fabricate high‐performance Li‐S batteries by in situ polymerization of polyaniline (PANi)/S/carbon nanofiber (CNF) cathode. Compared to traditional carbon black/S cathodes and other cathode materials with PANi polymer, this effective three‐dimensional (3D) cathode design has several advantages: (i) the interconnected and highly conductive CNF/PANi network structure facilitates the electron transfer between the insulating S and conductive CNF mat; (ii) the CNF/PANi network structure, with abundant oxygen and nitrogen heteroatoms, offers strong adsorption for the polysulfides; (iii) the 3D architecture of CNF/S/PANi helps accommodate the volume change of S during cycling and maintain the structural integrity of the cathode; (iv) the easy and simple fabrication process minimizes the time and energy costs; and (v) the freestanding composite cathode without additional polymer binder contributes to higher energy density of Li‐S batteries. With all the advantages mentioned above, Li‐S cells present a high S utilization with stable cycling performance for over 300 cycles with a low capacity decay rate of 0.08% cycle−1.
Environmental Control of the Topological Transition in Metal/Photoemissive‐Blend Metamaterials
Authors: Caligiuri Vincenzo , Lento Raffaella , Ricciardi Loredana , Termine Roberto , La Deda Massimo , Siprova Svetlana , Golemme Attilio , De Luca Antonio
Published: February 2018

The quest for unconventional optical materials finds natural answers in the field of plasmonics. Here, special composites can manifest singularities in their dielectric permittivity. The so‐called epsilon‐near‐zero (εNZ) condition is typically encountered in artificial materials called hyperbolic metamaterials (HMMs). Unfortunately, tuning the HMMs εNZ is still challenging. Here it is demonstrated how the εNZ frequency of an HMM can be reversibly tuned via thermally induced water absorption/desorption. The key element is a dielectric hygroscopic material, consisting of a blend of a polymer, a sol–gel unsintered TiO2, and an organic dye. Due to the hygroscopic nature of unsintered TiO2, an increase of temperature induces a reversible physical contraction of the thickness of the dielectric blend, as well as an increase of refractive index. This causes a remarkable 45 nm shift of the absorption peak of the embedded dye, acting as a chromatic label. When such a blend is embedded in an HMM, a reversible thermal tuning of the overall optical response, as well as an epsilon‐near‐zero wavelength shift by about 25 nm, is induced. The remarkable tuning range shown here, besides obvious HMM‐based temperature sensing applications, paves the way toward a plethora of new functions in which tunable εNZ materials are needed.
Ni‐Catalyzed C−F Bond Functionalization of Unactivated Aryl Fluorides and Corresponding Coupling with Oxazoles
Authors: Yin Youzhi , Yue Xiaoyu , Zhong Qi , Jiang Hanmin , Bai Ruopeng , Lan Yu , Zhang Hua
Published: February 2018

A Ni‐catalyzed C−F bond functionalization of unactivated aryl fluorides with oxazoles as coupling partners was developed. Various arylated oxazoles could be obtained in moderate to good yields in the presence of Ni(cod)2/IMes catalytic system. A rapid synthesis of natural product texaline was also demonstrated using this protocol. This transformation could be potentially utilized in regioselective introduction of an oxazole group in late‐stage synthetic applications.

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Advances in In Situ Techniques for Characterization of Failure Mechanisms of Li‐Ion Battery Anodes
Authors: Hapuarachchi Sashini N. S. , Sun Ziqi , Yan Cheng
Published: February 2018

Li‐ion rechargeable battery, the prevailing market leader for energy storage applications throughout the past few decades, needs to be improved greatly in terms of capacity, cycling performance, and safety to cater future generation energy requirements. The failure of electrode materials, which leads to early capacity decay and safety issues in existing Li‐ion batteries, however, is still a technical challenge and deserves further investigation. In this review, recent advances in how in situ characterization techniques can be adopted to understand material failure mechanisms in Li‐ion battery are highlighted with a focus on failure and degradation of negative electrode materials. The information presented in this article is believed to be beneficial to application of advanced in situ characterization techniques in the development of next‐generation battery systems with improved electrochemical properties and structural integrity.
Current topics in the surgical treatments for hepatocellular carcinoma
Authors: Ban Daisuke , Ogura Toshiro , Akahoshi Keiichi , Tanabe Minoru
Published: February 2018

Treatment strategy for hepatocellular carcinoma (HCC) requires optimal selection of therapies based on various factors related to tumor condition and liver functional reserve. Although several evidence‐based guidelines have been proposed for the treatment of HCC, the criteria and range of indications differ among these guidelines according to the circumstances of each country. In European nations and the USA, patients with the Barcelona Clinic Liver Cancer stage 0‐A are subjects for surgical resection, whereas in Asian countries, even those with the intermediate stage are regarded as surgical candidates. Furthermore, since the recent introduction and rapidly widely spreading use of laparoscopic liver resection, this technique has become an important treatment option for surgical resection. In this review article, we overview the current topics of treatment of HCC with a special focus on surgical therapy.
Small but wise: Common marmosets (Callithrix jacchus) use acoustic signals as cues to avoid interactions with blonde capuchin monkeys (Sapajus flavius)
Authors: Bastos Monique , Medeiros Karolina , Jones Gareth , Bezerra Bruna
Published: February 2018

Vocalizations are often used by animals to communicate and mediate social interactions. Animals may benefit from eavesdropping on calls from other species to avoid predation and thus increase their chances of survival. Here we use both observational and experimental evidence to investigate eavesdropping and how acoustic signals may mediate interactions between two sympatric and endemic primate species (common marmosets and blonde capuchin monkeys) in a fragment of Atlantic Rainforest in Northeastern Brazil. We observed 22 natural vocal encounters between the study species, but no evident visual or physical contact over the study period. These two species seem to use the same area throughout the day, but at different times. We broadcasted alarm and long distance calls to and from both species as well as two control stimuli (i.e., forest background noise and a loud call from an Amazonian primate) in our playback experiments. Common marmosets showed anti‐predator behavior (i.e., vigilance and flight) when exposed to blonde capuchin calls both naturally and experimentally. However, blonde capuchin monkeys showed no anti‐predator behavior in response to common marmoset calls. Blonde capuchins uttered long distance calls and looked in the direction of the speaker following exposure to their own long distance call, whereas they fled when exposed to their own alarm calls. Both blonde capuchin monkeys and common marmosets showed fear behaviors in response to the loud call from a primate species unknown to them, and showed no apparent response to the forest background noise. Common marmoset responses to blonde capuchin calls suggests that the latter is a potential predator. Furthermore, common marmosets appear to be eavesdropping on calls from blonde capuchin monkeys to avoid potentially costly encounters with them.
Paradoxical septal motion: A diagnostic approach and clinical relevance
Authors: Clancy David J. , Mclean Anthony , Slama Michel , Orde Sam R.
Published: February 2018

Abnormal septal motion (commonly referred to as septal bounce) is a common echocardiographic finding that occurs with several conditions, including the following: mitral stenosis, left bundle branch block, pericardial syndromes and severe pulmonary hypertension. We explore the subtle changes that occur on M‐mode imaging of the septum, other associated echocardiographic features, the impact of inspiratory effort on septal motion and relevant clinical findings. Finally, we discuss the impact of abnormal septal motion on cardiac form and function, proposing there is a clinically significant impact on biventricular filling and ejection.
Simultaneous Fenton‐like Ion Delivery and Glutathione Depletion by MnO2‐Based Nanoagent to Enhance Chemodynamic Therapy
Authors: Lin Li‐Sen , Song Jibin , Song Liang , Ke Kaimei , Liu Yijing , Zhou Zijian , Shen Zheyu , Li Juan , Yang Zhen , Tang Wei , Niu Gang , Yang Huang‐Hao , Chen Xiaoyuan
Published: February 2018

Chemodynamic therapy (CDT) utilizes iron‐initiated Fenton chemistry to destroy tumor cells by converting endogenous H2O2 into the highly toxic hydroxyl radical (.OH). There is a paucity of Fenton‐like metal‐based CDT agents. Intracellular glutathione (GSH) with .OH scavenging ability greatly reduces CDT efficacy. A self‐reinforcing CDT nanoagent based on MnO2 is reported that has both Fenton‐like Mn2+ delivery and GSH depletion properties. In the presence of HCO3−, which is abundant in the physiological medium, Mn2+ exerts Fenton‐like activity to generate .OH from H2O2. Upon uptake of MnO2‐coated mesoporous silica nanoparticles (MS@MnO2 NPs) by cancer cells, the MnO2 shell undergoes a redox reaction with GSH to form glutathione disulfide and Mn2+, resulting in GSH depletion‐enhanced CDT. This, together with the GSH‐activated MRI contrast effect and dissociation of MnO2, allows MS@MnO2 NPs to achieve MRI‐monitored chemo–chemodynamic combination therapy.
Mechanism‐Based Condition Screening for Sustainable Catalysis in Single‐Electron Steps by Cyclic Voltammetry
Authors: Liedtke Theresa , Spannring Peter , Riccardi Ludovico , Gansäuer Andreas
Published: February 2018

A cyclic‐voltammetry‐based screening method for Cp2TiX‐catalyzed reactions is introduced. Our mechanism‐based approach enables the study of the influence of various additives on the electrochemically generated active catalyst Cp2TiX, which is in equilibrium with catalytically inactive [Cp2TiX2]−. Thioureas and ureas are most efficient in the generation of Cp2TiX in THF. Knowing the precise position of the equilibrium between Cp2TiX and [Cp2TiX2]− allowed us to identify reaction conditions for the bulk electrolysis of Cp2TiX2 complexes and for Cp2TiX‐catayzed radical arylations without having to carry out the reactions. Our time‐ and resource‐efficient approach is of general interest for the design of catalytic reactions that proceed in single‐electron steps.
Narrow‐Bandgap Chalcogenoviologens for Electrochromism and Visible‐Light‐Driven Hydrogen Evolution
Authors: Li Guoping , Xu Letian , Zhang Weidong , Zhou Kun , Ding Yousong , Liu Fenglin , He Xiaoming , He Gang
Published: February 2018

A series of electron‐accepting chalcogen‐bridged viologens with narrow HOMO–LUMO bandgaps and low LUMO levels is reported. The optoelectronic properties of chalcogenoviologens can be readily tuned through heavy atom substitution (S, Se and Te). Herein, in situ electrochemical spectroscopy was performed on the proof‐of‐concept electrochromic devices (ECD). E‐BnV2+ (E=Se, Te; BnV2+=benzyl viologen) was used for the visible‐light‐driven hydrogen evolution due to the strong visible‐light absorption. Remarkably, E‐BnV2+ was not only used as a photosensitizer, but also as an electron mediator, providing a new strategy to explore photocatalysts. The higher apparent quantum yield of Se‐BnV2+ could be interpreted in terms of different energy levels, faster electron‐transfer rates and faster formation of radical species.
Eco‐friendly magnetic clinoptilolite containing Cu(0) nanoparticles (CuNPs/MZN): as a new efficient catalyst for the synthesis of propargylamines via A3 and KA2 coupling reactions
Authors: Khakzad Siuki Mohammad Mehdi , Bakavoli Mehdi , Eshghi Hossein
Published: February 2018

In this reaserch a new and eco‐friendly magnetic catalyst for the synthesis of propargylamines is reported. Initial incorporation of Fe3O4 magnetic nanoparticles (MNPs) into the pores of the natural clinoptilolite zeolite followed by modification with epichlorohydrine and ethylenediamine and then immobilization of CuNPs on the surface of functionalized zeolite gave the desired catalyst (CuNPs/MZN). The CuNPs/MZN was fully characterized by various techniques such as FT‐IR, CHN, TGA, ICP, XRD, SEM, TEM and BET. A host of propargylamines were readily synthesized through using the catalyst in high yields and short reaction times via A3 and KA2 coupling reactions of aldehydes/ketones, amines, and phenylacetylene. The CuNPs/MZN was easily separated from the reaction mixture by an external magnet and reused several times successfully. The catalyst has the potential for catalysis of various organic transformations.
Antibacterial and antibiofilm activity of nanochelating based silver nanoparticles against several nosocomial pathogens
Authors: Hoseini‐Alfatemi Seyedeh Mahsan , Karimi Abdollah , Armin Shahnaz , Fakharzadeh Saideh , Fallah Fatemeh , Kalanaky Somayeh
Published: February 2018

The emergence of multi‐drug resistant (MDR) bacteria and dynamic pattern of infectious diseases demand to develop alternative and more effective therapeutic strategies. Silver nanoparticles (AgNPs) are among the most widely commercialized engineered nanomaterials, because of their unique properties and increasing use for various applications in nanomedicine. This study for the first time aimed to evaluate the antibacterial and antibiofilm activities of newly synthesized nanochelating based AgNPs against several Gram‐positive and ‐negative nosocomial pathogens.

Nanochelating technology was used to design and synthesize the AgNPs. The cytotoxicity was tested in human cell line using the MTT assay. AgNPs minimal inhibitory concentration (MIC) was determined by standard broth microdilution. Antibiofilm activity was assayed by a microtiter‐plate screening method.

The two synthesized AgNPs including AgNPs (A) with the size of about 20‐25 nm, and AgNPs (B) with 30‐35 nm were tested against Staphylococcus aureus, Staphylococcus epidermidis, Acinetobacter baumannii, and Pseudomonas aeruginosa. AgNPs exhibited higher antibacterial activity against Gram‐positive strains. AgNPs were found to significantly inhibit the biofilm formation of tested strains in concentration 0.01 to 10 mg/mL. AgNPs (A) showed significant effective antibiofilm activity compared to AgNPs (B).

In summary, our results showed the promising antibacterial and antibiofilm activity of our new nanochelating based synthesized AgNPs against several nosocomial pathogens.
Fe3O4/ZnMg(Al)O magnetic nanoparticles for efficient biodiesel production
Authors: Chen Ying , Liu Tiancong , He Han , Liang Hongbao
Published: February 2018

Fe3O4/ZnMg(Al)O solid base catalyst was prepared by calcining ZnMgAl‐LDHs grown on the surface of magnetic Fe3O4 synthesized by chemical coprecipitation. The magnetic property of the catalyst was studied by vibrating sample magnetometer. The results showed that the catalyst possessed excellent magnetic responsivity, and it could be recovered by external magnetic field. The magnetic catalyst was also characterized by ICP, TG‐DTG, XRD, SEM, EDS, TEM and N2 absorption‐desorption. It was found that the catalyst showed a unique porous structure. The reaction conditions affecting biodiesel yield were investigated, the biodiesel yield reached 94% was obtained under the optimal conditions. The biodiesel yield was still above 82% after 7 times of regeneration, and the catalyst can be easily separated and recycled.
Design and Preparation of Poly‐Selenides: Easily Fabricated and Efficient Organoselenium Materials for Heavy Metal Removing and Recycling
Authors: Jing Xiaobi , Chen Changzhou , Deng Xin , Zhang Xu , Wei Duo , Yu Lei
Published: February 2018

Reaction of 1,4‐bis(chloromethyl)benzene with the in situ‐generated NaHSe afforded a facile fabrication method of poly‐selenide, a novel organoselenium material which was found to be efficient for heavy metal removing and recycling. The material could grab transition metals from their aqueous solutions and release them in HNO3. After treating with aqueous Na2SO3, the polymer could be refreshed and reused. It could absorb heavier Pb even than its own weight from high concentration solutions, and remove almost all of the Pb in dilute solutions.
Efficient and Response Surface Optimized Aqueous Enzymatic Extraction of Camellia oleifera (Tea Seed) Oil Facilitated by Concurrent Calcium Chloride Addition
Authors: Meng Xianghe , Ge Hangli , Ye Qin , Peng Li , Wang Zhongjiang , Jiang Lianzhou
Published: February 2018

This paper reports an efficient aqueous enzymatic extraction (AEE) method for Camellia oleifera seed oil with the aid of response surface analysis. A maximum oil recovery of ~93.5% was obtained when a 2‐step AEE process was performed using 0.80% cellulase (v/w) solution at pH 6.0 maintained at 50 °C for 1 h followed by a solution of 0.70% Alcalase® with pH 9.2 at 57 °C for 4.1 h. It was found that the addition of Ca2+ during the proteolysis stage improved the free oil yield from ~62.1 to ~86.6%. This was attributed to the removal of tea saponins, cross‐linkage of anionic polysaccharides, and destabilization of cream emulsion by Ca2+. This was verified by decreased tea saponin and polysaccharide levels in the cream emulsion and bulk solution as well as lowering of the emulsion fraction. It was determined that addition of CaCl2 solution in continuous flow to the proteolysate is superior to one‐time or batch addition in inhibiting emulsion formation. The addition of CaCl2 may provide a means of replacing the more laborious, time‐consuming demulsification process otherwise required.
Biolubricant Production of 2‐Ethylhexyl Palmitate by Transesterification Over Unsupported Potassium Carbonate
Authors: Zheng Ting , Wu Zhenyu , Xie Qinglong , Lu Meizhen , Xia Fan , Wang Guangquan , Nie Yong , Ji Jianbing
Published: February 2018

Owing to the decrease of global oil price, development of downstream value‐added products is important to biodiesel industry. In this study, we used palmitic acid methyl ester (PAME) as a starting material to produce 2‐ethylhexyl palmitate (2‐EHP), an environmentally friendly biolubricant product, which was derived from the transesterification of fatty acid methyl esters and long chain fatty alcohols. Conventional synthetic routes of 2‐EHP have disadvantages, including high catalyst price, low conversion efficiency, and pollution issues. To solve these problems, in situ transesterification of PAME with 2‐ethylhexanol (2‐EH) was conducted over unsupported potassium carbonate as heterogeneous catalyst. The optimal reaction temperature, 2‐EH to PAME molar ratio, and catalyst to PAME mass ratio were 180 °C, 3:1, and 3.0 wt%, respectively. The PAME conversion reached up to 100% within 1 hour under the optimal conditions. In addition, a kinetic model describing the experimental data over a temperature range of 160–180 °C was developed. The dependence of kinetic rate constant (k) on temperature was evaluated, and the activation energy (Ea) for the transesterification of PAME with 2‐EH was calculated to be 57.04 kJ mol−1.
Reversible photochromic nanofibrous membranes with excellent water/windproof and breathable performance
Authors: Liu Meng‐Nan , Yan Xu , You Ming‐Hao , Fu Jie , Nie Guang‐Di , Yu Miao , Ning Xin , Wan Yong , Long Yun‐Ze
Published: February 2018

Electrospun nanofibrous membranes (NFMs) with outstanding photochromic property, waterproof, and breathability have attracted considerable interest owing to their multifunctional applications in intelligent clothing, self‐cleaning, and protection. However, great challenges still remain in creating such functional materials. A novel waterproof–breathable membrane with robust photochromic property is fabricated by introducing photochromic microcapsule (PM) into electrospun thermoplastic polyurethanes (TPU) membranes. Compared with the pristine TPU NFMs, the composite TPU/PM membranes are endowed with reversible photochromic properties. In addition, the composite membranes not only exhibited a water contact angle of 137° and a milk contact angle of 130°, but also had integrated properties of modest water vapor transmittance rate of 19,278 g m−2 day−1, high air permeability of 962 mm s−1, low waterproofness of 2.813 kPa, and comparable tensile strength of 12.08 MPa. Furthermore, the convenience and efficiency of this fabrication process will allow for large‐scale production of the multifunctional NFMs. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46342.
Synthesis and characterization of poly(methyl methacrylate)/polysiloxane composites and their coating properties
Authors: Xing ChengPeng , He Ting , Peng YinJie , Li RuiHai
Published: February 2018

A series of poly(methyl methacrylate) (PMMA)/polysiloxane composites and their coatings were prepared as designed. A copolymer (PMMAVTEOS) containing methyl methacrylate (MMA) and vinyltriethoxysilane (VTEOS) was prepared by free radical polymerization and then condensed with methyl triethoxysilane (MTES) to fabricate PMMA/polysiloxane composites; their corresponding coatings were obtained via a curing process in an oven (at 75 °C). The polymers were characterized by gel permeation chromatography and Fourier transform infrared spectroscopy. The surface property, hardness, water contact angle, thermal stability, and optical property of the coatings were investigated by scanning electron microscopy, pencil hardness testing, water contact angle testing, thermogravimetric analysis, and ultraviolet–visible spectroscopy, respectively. The results showed that, after addition of MMA, the pencil hardness of the coatings was reduced from 6H to 2H and the thermal stability decreased from 365 to 314 °C. However, it increased the flexibility and adhesion properties (the water contact angle increased from 94.7° to 102.1°). The transparent PMMA/polysiloxane coatings showed excellent scratch resistance, a smooth surface, high thermal stability, and a strong adhesion property. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46358.