bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photonic Sensing of Reactive Atmospheric Species
Authors: Chen Weidong , Yi Hongming , Wu Tao , Zhao Weixiong , Lengignon Christophe , Wang Gaoxuan , Fertein Eric , Coeur Cécile , Wysocki Gerard , Wang Tao , Sigrist Markus W. , Gao Xiaoming , Zhang Weijun 
Published: September 2017

AbstractChemically reactive short‐lived atmospheric species play a crucial role in tropospheric processes that affect regional air quality and global climate change. Contrary to long‐lived species (such as greenhouse gases), fast, interference‐free, accurate, and precise in situ monitoring of such strongly reactive species represents a real challenge owing to their very high reactivity resulting in short lifetimes (∼1–100 s) and ultralow concentrations (∼pptv). In this article, we give an overview of the recent progress in the development of absorption spectroscopy‐based photonic instruments involving modern photonic light sources (quantum cascade laser, distributed feedback diode laser, and light‐emitting diode) combined with high‐sensitivity spectroscopic measurement techniques such as incoherent broadband cavity‐enhanced absorption spectroscopy, Faraday rotation spectroscopy, wavelength‐modulation‐enhanced off‐axis integrated cavity output spectroscopy, tuning fork‐ or microphone‐based photoacoustic spectroscopy, and open‐path multipass absorption spectroscopy. Illustrative examples of monitoring some key atmospheric reactive species (such as HONO, OH, NO3, N2O5, and NO2) will be presented for applications in intensive field campaigns, instrumented atmospheric simulation chamber, or laboratory investigation.
Engineered Axonal Tracts as “Living Electrodes” for Synaptic‐Based Modulation of Neural Circuitry
Authors: Serruya Mijail D. , Harris James P. , Adewole Dayo O. , Struzyna Laura A. , Burrell Justin C. , Nemes Ashley , Petrov Dmitriy , Kraft Reuben H. , Chen H. Isaac , Wolf John A. , Cullen D. Kacy 
Published: September 2017

AbstractBrain–computer interface and neuromodulation strategies relying on penetrating non‐organic electrodes/optrodes are limited by an inflammatory foreign body response that ultimately diminishes performance. A novel “biohybrid” strategy is advanced, whereby living neurons, biomaterials, and microelectrode/optical technology are used together to provide a biologically‐based vehicle to probe and modulate nervous‐system activity. Microtissue engineering techniques are employed to create axon‐based “living electrodes”, which are columnar microstructures comprised of neuronal population(s) projecting long axonal tracts within the lumen of a hydrogel designed to chaperone delivery into the brain. Upon microinjection, the axonal segment penetrates to prescribed depth for synaptic integration with local host neurons, with the perikaryal segment remaining externalized below conforming electrical–optical arrays. In this paradigm, only the biological component ultimately remains in the brain, potentially attenuating a chronic foreign‐body response. Axon‐based living electrodes are constructed using multiple neuronal subtypes, each with differential capacity to stimulate, inhibit, and/or modulate neural circuitry based on specificity uniquely afforded by synaptic integration, yet ultimately computer controlled by optical/electrical components on the brain surface. Current efforts are assessing the efficacy of this biohybrid interface for targeted, synaptic‐based neuromodulation, and the specificity, spatial density and long‐term fidelity versus conventional microelectronic or optical substrates alone.
A Mesocrystal‐Like Morphology Formed by Classical Polymer‐Mediated Crystal Growth
Authors: Smeets Paul J. M. , Cho Kang Rae , Sommerdijk Nico A. J. M. , De Yoreo James J. 
Published: September 2017

AbstractGrowth by oriented assembly of nanoparticles is a widely reported phenomenon for many crystal systems. While often deduced through morphological analyses, direct evidence for this assembly behavior is limited and, in the calcium carbonate (CaCO3) system, has recently been disputed. However, in the absence of a particle‐based pathway, the mechanism responsible for the creation of the striking morphologies that appear to consist of subparticles is unclear. Therefore, in situ atomic force microscopy is used to investigate the growth of calcite crystals in solutions containing a polymer additive known for its ability to generate crystal morphologies associated with mesocrystal formation. It is shown that classical growth processes that begin with impurity pinning of atomic steps, leading to stabilization of new step directions, creation of pseudo‐facets, and extreme surface roughening, can produce a microscale morphology previously attributed to nonclassical processes of crystal growth by particle assembly.
Elastic Modulus Dependence on the Specific Adhesion of Hydrogels
Authors: Wang Hanqing , Jacobi Fawad , Waschke Johannes , Hartmann Laura , Löwen Hartmut , Schmidt Stephan 
Published: September 2017

AbstractMechanosensitivity in biology, e.g., cells responding to material stiffness, is important for the design of synthetic biomaterials. It is caused by protein receptors able to undergo conformational changes depending on mechanical stress during adhesion processes. Here the elastic modulus dependence of adhesive interactions is systematically quantified using ligand–receptor model systems that are generally not thought to be mechanosensitive: biotin–avidin, mannose–concanavalin A, and electrostatic interactions between carboxylic acids and polycationic surfaces. Interactions are measured by microgel sensors of different stiffness adhering to surfaces presenting a corresponding binding partner. Adhesion is generally decreased for softer microgels due to reduced density of binding partners. Density‐normalized data show that low‐affinity carbohydrate ligands exhibit reduced binding in softer networks, probably due to increased network conformational entropy. However, in case of stronger interactions with large interaction range (electrostatic) and large lifetime (biotin–avidin) density normalized adhesion is increased. This suggests compensation of entropic repulsion for softer networks probably due to their increased mechanical deformation upon microgel adhesion and enhanced cooperative binding. In essence, experiments indicate that soft interacting polymer materials exhibit entropic repulsion, which can be overcome by strongly interacting species in the network harnessing network flexibility in order to increase adhesion.
Self‐Assembling Azaindole Organogel for Organic Light‐Emitting Devices (OLEDs)
Authors: Martín Cristina , Kennes Koen , Van der Auweraer Mark , Hofkens Johan , de Miguel Gustavo , García‐Frutos Eva M. 
Published: September 2017

AbstractThis study reports on the use of a self‐assembling organogel, 5‐(4‐nonylphenyl)‐7‐azaindole (1), as a new emitter in small‐molecule organic light emitting devices (OLEDs). The theoretical calculations along with the photophysical characterization studies suggest the coexistence of the monomer and dimer species at high concentration of compound 1. The presence of this type of dimer (formed via H‐bonding) is responsible for the increased emission. However, the most notable feature is the 3D network of vastly interconnected fibers formed in the organogel that modifies the photophysical properties. Based on this, several OLED architectures are made in order to understand the mechanism involved in the electroluminescence (EL) behavior of 1. Although the position of the EL spectra differs from that of the photoluminescence (PL) spectra, the trends observed in the device properties perfectly match with dimer formation. In this framework a better device performance is associated to a higher efficiency of dimer formation, which optimizes in the OLED prepared from the organogel. Therefore, these results show that the rational combination of a moiety showing a strong PL intensity increased upon aggregation with organogel properties is an efficient strategy to create alternative emitters for OLED devices.
Nanoarchitectonics for Hybrid and Related Materials for Bio‐Oriented Applications
Authors: Ariga Katsuhiko , Leong David Tai , Mori Taizo 
Published: September 2017

AbstractAtom/molecular‐level controls in nanotechnology are important for the precise placement of components in device applications. Despite many advances, nanotechnology still uses simple systems to make precise atom/molecule‐scale changes. This is in contrast with the many phenomena observed in biological systems, where there appears to be a well‐designed integrative approach involving molecular units to achieve atomic‐ and molecular‐scale changes. Inspired by nature, we introduced a novel concept—nanoarchitectonics—to develop nanoscale functional materials for bio‐oriented applications. Nanoarchitectonics is a unified concept combining nanotechnology and methodologies in related research fields, such as supramolecular chemistry, self‐assembly, and self‐organization, to satisfy the major features of nanosciences for the creation of functional materials or even devices and machines. This concept guides the harmonized assembly of nanoscale objects into higher order functional materials. In this Feature Article, recent research activities are introduced regarding the development of advanced functional materials of hybrid and related architectures on the basis of nanoarchitectonics from diverse contexts of organic and inorganic materials: i) from biology (DNA‐based hybrid); ii) from geology (clay‐based hybrid); iii) from 0D nanotechnology (fullerene‐based hybrid); and iv) from other nanoarchitectonics. Therefore, this Feature Article showcases some examples of the nanoarchitectonic concepts at work in diverse material types.
Highly Efficient Self‐Healable and Dual Responsive Cellulose‐Based Hydrogels for Controlled Release and 3D Cell Culture
Authors: Yang Xuefeng , Liu Guoqiang , Peng Liao , Guo Jinhua , Tao Lei , Yuan Jinying , Chang Chunyu , Wei Yen , Zhang Lina 
Published: September 2017

AbstractTo face the increasing demand of self‐healing hydrogels with biocompatibility and high performances, a new class of cellulose‐based self‐healing hydrogels are constructed through dynamic covalent acylhydrazone linkages. The carboxyethyl cellulose‐graft‐dithiodipropionate dihydrazide and dibenzaldehyde‐terminated poly(ethylene glycol) are synthesized, and then the hydrogels are formed from their mixed solutions under 4‐amino‐DL‐phenylalanine (4a‐Phe) catalysis. The chemical structure, as well as microscopic morphologies, gelation times, mechanical and self‐healing performances of the hydrogels are investigated with 1H NMR, Fourier transform infrared spectroscopy, atomic force microscopy, rheological and compression measurements. Their gelation times can be controlled by varying the total polymer concentration or 4a‐Phe content. The resulted hydrogels exhibit excellent self‐healing ability with a high healing efficiency (≈96%) and good mechanical properties. Moreover, the hydrogels display pH/redox dual responsive sol‐gel transition behaviors, and are applied successfully to the controlled release of doxorubicin. Importantly, benefitting from the excellent biocompatibility and the reversibly cross‐linked networks, the hydrogels can function as suitable 3D culture scaffolds for L929 cells, leading to the encapsulated cells maintaining a high viability and proliferative capacity. Therefore, the cellulose‐based self‐healing hydrogels show potential applications in drug delivery and 3D cell culture for tissue engineering.
Nutlin‐3a and Cytokine Co‐loaded Spermine‐Modified Acetalated Dextran Nanoparticles for Cancer Chemo‐Immunotherapy
Authors: Bauleth‐Ramos Tomás , Shahbazi Mohammad‐Ali , Liu Dongfei , Fontana Flavia , Correia Alexandra , Figueiredo Patrícia , Zhang Hongbo , Martins João Pedro , Hirvonen Jouni T. , Granja Pedro , Sarmento Bruno , Santos Hélder A. 
Published: September 2017

AbstractThe combination of chemo‐ and immunotherapy represents one promising strategy to overcome the existent challenges in the present‐day anticancer therapy. Here, spermine‐modified acetalated dextran nanoparticles (Sp‐AcDEX NPs), co‐loaded with the non‐genotoxic molecule Nutlin‐3a (Nut3a), and the cytokine granulocyte–macrophage colony‐stimulating factor (GM‐CSF), are developed to induce cancer cell death and create a specific antitumor immune response. These polymeric NPs release Nut3a in a pH dependent fashion and induce endosomal escape. Due to Nut3a, the loaded NPs exert specific toxicity toward wild‐type p53 cancer cells while avoiding toxicity in immune cells. Furthermore, the NPs show intrinsic immune adjuvancy on monocyte derived‐dendritic cells, upregulating the expression of cell surface CD83 and CD86 costimulatory markers. Finally, it is examined that by inducing MCF‐7 breast cancer cell death and acting as immune adjuvants, the NPs can downregulate the expression of IL‐10 and upregulate IL‐1β, leading to proliferation of CD3+ and cytotoxic CD8+ T cells. Overall, the study suggests that Sp‐AcDEX NPs loaded with Nut3a and GM‐CSF is a promising system for chemo‐immunotherapy, capable of inducing tumor cell death and stimulating immune response.
Highly Stretchable, Compliant, Polymeric Microelectrode Arrays for In Vivo Electrophysiological Interfacing
Authors: Qi Dianpeng , Liu Zhiyuan , Liu Yan , Jiang Ying , Leow Wan Ru , Pal Mayank , Pan Shaowu , Yang Hui , Wang Yu , Zhang Xiaoqian , Yu Jiancan , Li Bin , Yu Zhe , Wang Wei , Chen Xiaodong 
Published: September 2017

AbstractPolymeric microelectrode arrays (MEAs) are emerging as a new generation of biointegrated microelectrodes to transduce original electrochemical signals in living tissues to external electrical circuits, and vice versa. So far, the challenge of stretchable polymeric MEAs lies in the competition between high stretchability and good electrode–substrate adhesion. The larger the stretchability, the easier the delamination of electrodes from the substrate due to the mismatch in their Young's modulus. In this work, polypyrrole (PPy) electrode materials are designed, with PPy nanowires integrated on the high conductive PPy electrode arrays. By utilizing this electrode material, for the first time, stretchable polymeric MEAs are fabricated with both high stretchability (≈100%) and good electrode–substrate adhesion (1.9 MPa). In addition, low Young's modulus (450 kPa), excellent recycling stability (10 000 cycles of stretch), and high conductivity of the MEAs are also achieved. As a proof of concept, the as‐prepared polymeric MEAs are successfully used for conformally recording the electrocorticograph signals from rats in normal and epileptic states, respectively. Further, these polymeric MEAs are also successful in stimulating the ischiadic nerve of the rat. This strategy provides a new perspective to the highly stretchable and mechanically stable polymeric MEAs, which are vital for compliant neural electrodes.
Efficient Heterogeneous Gold(I)‐Catalyzed Direct C(sp2)–C(sp) Bond Functionalization of Arylalkynes through a Nitrogenation Process to Amides
Authors: Nie Quan , Yi Feiyan , Huang Bin , Cai Mingzhong 
Published: September 2017

AbstractThe first heterogeneous gold(I)‐catalyzed direct C(sp2)–C(sp) bond functionalization of arylalkynes through a nitrogenation process to amides has been achieved by using an ordered mesoporous silica (MCM‐41)‐immobilized phosphine gold(I) complex [MCM‐41‐PPh3‐AuCl] as catalyst and silver carbonate (Ag2CO3) as cocatalyst with trimethylsilyl azide (TMSN3) as a nitrogen source, yielding a variety of amides in moderate to excellent yields under mild conditions. This heterogeneous phosphine gold(I) complex shows the same turnover numbers as the homogeneous chloro(triphenylphosphine)gold(I) (Ph3PAuCl) and can easily be recovered by simple filtration of the reaction solution and recycled at least eight times without significant loss of activity, providing a novel, efficient, practical and economic method for the synthesis of amides from alkynes.magnified image
Silk‐Based Fine Dust Filters for Air Filtration
Authors: Jokisch Stephan , Neuenfeldt Martin , Scheibel Thomas 
Published: September 2017

AbstractState‐of‐the‐art air filter devices have been well‐characterized and optimized for particle deposition of a huge range of particle sizes. However, sustainability of the employed filter materials is usually neglected. In this study, several polymers (recombinant spider silk, recombinant lacewing silk, poly(lactic acid), and poly(ethylene oxide)) are electrospun into fine dust filter layers to evaluate relevant filter parameters such as particle deposition, air permeability, and pressure drop for sub‐micrometer fiber materials. Filters comprising silk proteins show a much lower demand on fine‐dust‐layer material (40–210 mg m−2) in comparison to that of conventional filters (50 g m−2). Filters equipped with silk meshes with fiber diameters in the sub‐micrometer regime (<250 nm) show improved filter qualities in comparison to that of commercially available air filter devices (with melt blown fibers in the >20 µm regime). In particular, sub‐micrometer particles (0.2–1 µm) are filtered more efficiently by the silk‐based filters due to interception and impaction effects yielding a low pressure drop, and therefore these filters show an improved air permeability and lowered pressure drop of, for example, a vacuum cleaner bag in which they can be employed.
Single‐Atom to Single‐Atom Grafting of Pt1 onto FeN4 Center: Pt1@FeNC Multifunctional Electrocatalyst with Significantly Enhanced Properties
Authors: Zeng Xiaojun , Shui Jianglan , Liu Xiaofang , Liu Qingtao , Li Yongcheng , Shang Jiaxiang , Zheng Lirong , Yu Ronghai 
Published: September 2017

AbstractNonprecious metal catalysts (NPMCs) FeNC are promising alternatives to noble metal Pt as the oxygen reduction reaction (ORR) catalysts for proton‐exchange‐membrane fuel cells. Herein, a new modulation strategy is reported to the active moiety FeN4 via a precise “single‐atom to single‐atom” grafting of a Pt atom onto the Fe center through a bridging oxygen molecule, creating a new active moiety of Pt1O2Fe1N4. The modulated FeNC exhibits remarkably improved ORR stabilities in acidic media. Moreover, it shows unexpectedly high catalytic activities toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), with overpotentials of 310 mV for OER in alkaline solution and 60 mV for HER in acidic media at a current density of 10 mA cm−2, outperforming the benchmark RuO2 and comparable with Pt/C(20%), respectively. The enhanced multifunctional electrocatalytic properties are associated with the newly constructed active moiety Pt1O2Fe1N4, which protects Fe sites from harmful species. Density functional theory calculations reveal the synergy in the new active moiety, which promotes the proton adsorption and reduction kinetics. In addition, the grafted Pt1O2 dangling bonds may boost the OER activity. This study paves a new way to improve and extend NPMCs electrocatalytic properties through a precisely single‐atom to single‐atom grafting strategy.
An Efficient and Earth‐Abundant Oxygen‐Evolving Electrocatalyst Based on Amorphous Metal Borides
Authors: Nsanzimana Jean Marie Vianney , Peng Yuecheng , Xu Yang Yang , Thia Larissa , Wang Cheng , Xia Bao Yu , Wang Xin 
Published: September 2017

AbstractCost‐effective and efficient oxygen‐evolving electrocatalysts are urgently required for energy storage and conversion technologies. In this work, an amorphous trimetallic boride nanocatalyst (Fe–Co–2.3Ni–B) prepared by a simple approach is reported as a highly efficient oxygen evolution reaction electrocatalyst. It exhibits an overpotential (η) of 274 mV to deliver a geometric current density (jgeo) of 10 mA cm−2, a small Tafel slope of 38 mV dec−1, and excellent long‐term durability at a mass loading of 0.3 mg cm−2. The impressive electrocatalytic performance originates from the unique amorphous multimetal–metalloid complex nanostructure. From application's point of view, this work holds great promise as this process is simple and allows for large‐scale production of cheap, yet efficient, material.
Concussion in adolescence and risk of multiple sclerosis
Authors: Montgomery Scott , Hiyoshi Ayako , Burkill Sarah , Alfredsson Lars , Bahmanyar Shahram , Olsson Tomas 
Published: September 2017

ObjectiveTo assess whether concussion in childhood or adolescence is associated with subsequent multiple sclerosis (MS) risk. Previous research suggests an association, but methodological limitations included retrospective data collection and small study populations.MethodsThe national Swedish Patient Register (hospital diagnoses) and MS Register were used to identify all MS diagnoses up to 2012 among people born since 1964, when the Patient Register was established. The 7,292 patients with MS were matched individually with 10 people without MS by sex, year of birth, age/vital status at MS diagnosis, and region of residence (county), resulting in a study population of 80,212. Diagnoses of concussion and control diagnoses of broken limb bones were identified using the Patient Register from birth to age 10 years or from age 11 to 20 years. Conditional logistic regression was used to examine associations with MS.ResultsConcussion in adolescence was associated with a raised risk of MS, producing adjusted odds ratios (95% confidence intervals) of 1.22 (1.05–1.42, p = 0.008) and 2.33 (1.35–4.04, p = 0.002) for 1 diagnosis of concussion and >1 diagnosis of concussion, respectively, compared with none. No notable association with MS was observed for concussion in childhood, or broken limb bones in childhood and adolescence.InterpretationHead trauma in adolescence, particularly if repeated, is associated with a raised risk of future MS, possibly due to initiation of an autoimmune process in the central nervous system. This further emphasizes the importance of protecting young people from head injuries. Ann Neurol 2017;82:554–561
Helicity Multiplexed Spin‐Orbit Interaction in Metasurface for Colorized and Encrypted Holographic Display
Authors: Zhang Xiaohu , Pu Mingbo , Jin Jinjin , Li Xiong , Gao Ping , Ma Xiaoliang , Wang Changtao , Luo Xiangang 
Published: September 2017

AbstractThe photonic spin‐orbit interaction (PSOI) in inhomogeneous anisotropic metasurface has drawn much attentions recently due to its superior ability to manipulate light wave in the deep‐subwavelength scale. Traditional methods involving PSOI are limited to operational spectral bandwidth owing to the intrinsic dispersion of the constitutive materials. In this paper, a helicity‐multiplexing scheme is proposed to achieve independent control of the PSOI in both the spectral and spatial domains by combining the broadband characteristic with polarization dependence of the metasurface. Two simultaneous functions of multicolor holographic display and polarization encryption are experimentally demonstrated with a single metasurface perforated with nanoholes. Although the optical response of the nanoholes themselves are almost independent of the light wavelength, the obtained image can have abundant spectral information. The approach proposed here is promising for realizing multifunction optical device, multicolor display, optical storage and information encryption.