bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of yield curves and porous crush on hydrocode simulations of asteroid airburst
Authors: Robertson D. K. , Mathias D. L.
Published: February 2017

Simulations of asteroid airburst are being conducted to obtain best estimates of damage areas and assess sensitivity to variables for asteroid characterization and mitigation efforts. The simulations presented here employed the ALE3D hydrocode to examine the breakup and energy deposition of asteroids entering the Earth's atmosphere, using the Chelyabinsk meteor as a test case. This paper examines the effect of increasingly complex material models on the energy deposition profile. Modeling the meteor as a rock having a single strength can reproduce airburst altitude and energy deposition reasonably well but is not representative of real rock masses (large bodies of material). Accounting for a yield curve that includes different tensile, shear, and compressive strengths shows that shear strength determines the burst altitude. Including yield curves and compaction of porous spaces in the material changes the detailed mechanics of the breakup but only has a limited effect on the burst altitude and energy deposition. Strong asteroids fail and create peak energy deposition close to the altitude at which ram dynamic pressure equals the material strength. Weak asteroids, even though they structurally fail at high altitude, require the increased pressure at lower altitude to disrupt and disperse the rubble. As a result, a wide range of weaker asteroid strengths produce peak energy deposition at a similar altitude.
Stretchable Active Matrix Inorganic Light‐Emitting Diode Display Enabled by Overlay‐Aligned Roll‐Transfer Printing
Authors: Choi Minwoo , Jang Bongkyun , Lee Wonho , Lee Seonwoo , Kim Tae Woong , Lee Hak‐Joo , Kim Jae‐Hyun , Ahn Jong‐Hyun
Published: February 2017

An active matrix‐type stretchable display is realized by overlay‐aligned transfer of inorganic light‐emitting diode (LED) and single‐crystal Si thin film transistor (TFT) with roll processes. The roll‐based transfer enables integration of heterogeneous thin film devices on a rubber substrate while preserving excellent electrical and optical properties of these devices, comparable to their bulk properties. The electron mobility of the integrated Si‐TFT is over 700 cm2V−1s−1, and this is attributed to the good interface between the Si channel and the thermally grown SiO2insulator. The light emission properties of the LED are of wafer quality. The resulting display stably operates under tensile strains up to 40%, over 200 cycles, demonstrating the potential of stretchable displays based on inorganic materials.
Iron(III) Chloride‐Mediated Regio‐ and Stereoselective Chlorosulfonylation of Alkynes and Alkenes with Sodium Sulfinates
Authors: Zeng Kui , Chen Lang , Chen Yi , Liu Yongping , Zhou Yongbo , Au Chak‐Tong , Yin Shuang‐Feng
Published: February 2017

The atom‐economic and one‐pot regio‐ and stereoselective addition of sodium arenesulfinates to either alkynes or alkenes can be achieved with an iron(III) chloride hexahydrate [FeCl3⋅6 H2O] catalytic system to afford β‐haloalkenyl and β‐chloroalkyl sulfones in moderate to good yields.

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Electrophilic Derivatization of Trifluoromethyl‐Substituted Semisquarate Using Unsaturated Organosilanes and Subsequent Ring Transformations
Authors: Kurohara Takashi , Shibuya Masatoshi , Yamamoto Yoshihiko
Published: February 2017

To extend the synthetic potential of trifluoromethyl‐substituted semisquarate (CF3‐semisquarate) previously synthesized by us as a pluripotent building block, its electrophilic derivatization was investigated. The electrophilic addition of allylic silanes and silyl enolates to CF3‐semisquarate afforded the corresponding 4‐hydroxycyclobutenones. Subsequent ring expansion of these products via thermolysis or oxidation using lead tetraacetate afforded trifluoromethylated bicyclo[3.2.0]heptenones or (Z)‐γ‐alkylidenetetronates.

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Palladium‐Catalyzed Addition of Arylboronic Acids to para‐ Quinone Methides for Preparation of Diarylacetates
Authors: Zhuge Ruijing , Wu Liang , Quan Mao , Butt Nicholas , Yang Guoqiang , Zhang Wanbin
Published: February 2017

A palladium‐catalyzed addition of arylboronic acids to para‐quinone methides has been developed. The catalytic system employing 4,4′‐dimethoxy‐2,2′‐bipyridine (DMeO‐BPy) as ligand and trifluoroethanol (TFE) as solvent provides diarylacetate products in high yields. A wide range of functionalized arylboronic acids can be used and the method tolerates some variation in the scope of the para‐quinone methides.

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Utilizing an Encapsulated Solution of Reagents to Achieve the Four‐Component Synthesis of (Benzo)Thiophene Derivatives
Authors: Shen Chaoren , Spannenberg Anke , Auer Matthias , Wu Xiao‐Feng
Published: February 2017

Reagent capsules can help to resolve the compatibility problem of reagents in multicomponent processes. Herein we demonstrate a facile method for encapsulating smelly liquid chemicals and its application in a modular palladium‐catalyzed carbonylative synthesis of multi‐substituted thiophenes from terminal alkynes and aryl iodides as well as a palladium‐catalyzed carbonylative synthesis of benzothiophene derivatives from aryl iodides and arylboronic acids. Here, the capsule plays a pivotal role in solving the issues on reaction condition incompatibilities and selectivity of multicomponent reactions as well as avoiding deactivation of the catalyst by releasing the reagents when the reaction temperature is raised. It greatly facilitates the development of highly‐efficient multicomponent reactions and demonstrates a modular pathway to obtain functionalized molecules.

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Magnetic ionic liquid‐water Janus droplets: Preparation, structure and morphology adjustment and magnetic manipulation
Authors: Guo Peng , Zeng Changfeng , Wang Chongqing , Zhang Lixiong
Published: February 2017

Surfactant‐free magnetic ionic liquid (MIL)‐water Janus microdroplets with adjustable structures and morphologies are prepared in capillary‐based microfluidic devices. Their morphologies (e.g., sizes, curvatures of the interfaces, and structures from Janus to core/shell) can be adjusted in a wide range by changing the flow rate ratio of water to MIL, adding different mass fractions of polyethylene glycol in water, and using soybean oil rather than liquid paraffin as the continuous phase. MIL‐water‐MIL ternary Janus magnetic microdroplets with adjustable symmetric and asymmetric structures are also prepared. These Janus microdroplets can be manipulated by magnetic attraction, leading to easy formation of water‐MIL‐water, MIL‐water‐oil, necklace‐structured MIL‐water alternative Janus droplets as well as more complex Janus droplets, such as MIL‐CO2‐in‐water and MIL‐water‐water droplets. Such preparation strategy is simple and can be applied in fields like pharmaceuticals, multi‐drug chemotherapies, and catalysis with expensive materials. © 2017 American Institute of Chemical EngineersAIChE J, 63: 4115–4123, 2017
Brief communication: Correlation between elastic modulus and radiographic density in mandibular cortical bone of colobine monkeys
Authors: Rapoff Andrew J. , Scott McGraw W. , Duque Ana , Daegling David J.
Published: February 2017

Objectives

The relationship between radiographic grayscale and elastic modulus was determined using mandibular cortical bone of colobine monkeys. Quantification of this relationship is critical for establishing absolute measures of structural rigidity of skeletal elements.

Materials and methods

We determined the Vickers microhardness values in mandibular bone from two species of African colobine monkeys and related these values to elastic modulus through an empirically determined correlation. We also determined radiographic grayscale values from microcomputed tomographic scans of the mandible in the same regions in which microhardness was sampled. We then correlated modulus to grayscale with a power law relationship.

Results

We found that elastic modulus scaled with negative allometry with respect to grayscale with an exponent of 0.77.

Discussion

Our results suggest a single exponent can effectively capture the relationship of grayscale to elastic modulus and facilitate development of heterogeneous structural models for use in comparative and computational biomechanical studies.
The Extension of Baird's Rule to Twisted Heteroannulenes: Aromaticity Reversal of Singly and Doubly Twisted Molecular Systems in the Lowest Triplet State
Authors: Hong Yongseok , Oh Juwon , Sung Young Mo , Tanaka Yasuo , Osuka Atsuhiro , Kim Dongho
Published: February 2017

We have investigated the aromaticity of singly twisted Möbius aromatic and doubly twisted Hückel antiaromatic bis(palladium(II)) [36]octaphyrins in the lowest triplet state (T1) by spectroscopic measurements and quantum calculations. The T1 state of the singly twisted Möbius [36]octaphyrin shows broad and weak absorption spectral features that are analogous to those of antiaromatic expanded porphyrins while the T1 state of the doubly twisted Hückel [36]octaphyrin exhibits intense and distinct spectral features, indicating the aromatic nature. These results along with theoretical calculations support the hypothesis that the aromaticity is reversed in the T1 state. Furthermore, we show that the degree of structural smoothness affects the aromaticity reversal in the T1 state.
Automated Synthesis of Well‐Defined Polymers and Biohybrids by Atom Transfer Radical Polymerization Using a DNA Synthesizer
Authors: Pan Xiangcheng , Lathwal Sushil , Mack Stephanie , Yan Jiajun , Das Subha R. , Matyjaszewski Krzysztof
Published: February 2017

A DNA synthesizer was successfully employed for preparation of well‐defined polymers by atom transfer radical polymerization (ATRP), in a technique termed AutoATRP. This method provides well‐defined homopolymers, diblock copolymers, and biohybrids under automated photomediated ATRP conditions. PhotoATRP was selected over other ATRP methods because of mild reaction conditions, ambient temperature, tolerance to oxygen, and no need to introduce reducing agents or radical initiators. Both acrylate and methacrylate monomers were successfully polymerized with excellent control in the DNA synthesizer. Diblock copolymers were synthesized with different targeted degrees of polymerization and with high retention of chain‐end functionality. Both hydrophobic and hydrophilic monomers were grafted from DNA. The DNA‐polymer hybrids were characterized by SEC and DLS. The AutoATRP method provides an efficient route to prepare a range of different polymeric materials, especially polymer‐biohybrids.
A Metal Chelating Porous Polymeric Support: The Missing Link for a Defect‐Free Metal–Organic Framework Composite Membrane
Authors: Barankova Eva , Tan Xiaoyu , Villalobos Luis Francisco , Litwiller Eric , Peinemann Klaus‐Viktor
Published: February 2017

Since the discovery of size‐selective metal–organic frameworks (MOFs), researchers have tried to incorporate these materials into gas separation membranes. Impressive gas selectivities were found, but these MOF membranes were mostly made on inorganic supports, which are generally too bulky and expensive for industrial gas separation. Forming MOF layers on porous polymer supports is industrially attractive but technically challenging. Two features to overcome these problems are described: 1) a metal chelating support polymer to bind the MOF layer, and 2) control of MOF crystal growth by contra‐diffusion, aiming at a very thin nanocrystalline MOF layer. Using a metal chelating poly‐thiosemicarbazide (PTSC) support and adjusting the metal and organic ligand concentrations carefully, a very compact ZIF‐8 (ZIF=zeolitic imidazolate framework) layer was produced that displayed interference colors because of its smooth surface and extreme thinness—within the range of visible light. High performances were measured in terms of hydrogen/propane (8350) and propylene/propane (150) selectivity.
Katalytische Desaromatisierung von N‐Heteroarenen mit Silicium‐ und Borverbindungen
Authors: Park Sehoon , Chang Sukbok
Published: February 2017

Desaromatisierte N‐Heterocyclen sind als Strukturmotive für die organische Synthese und die chemische Biologie von Bedeutung. Die katalytische desaromatisierende Reduktion von nicht aktivierten N‐Heteroarenen mit Silicium‐ und/oder Borverbindungen als Reduktionsmittel ist eine der direktesten Alternativen zur Hydrierung. Bisher wurden jedoch nur vereinzelte Beispiele zur katalytischen Reduktion von N‐Heteroarenen mit Silan‐ oder Boranreduktionsmitteln beschrieben. In diesem Aufsatz wird über jüngste Fortschritte bei der katalytischen Reduktion von nicht aktivierten N‐Heteroarenen mit Hydrosilanen, Hydroboranen, Silaboranen und Diboranen berichtet. Dabei wird vor allem auf die chemische Reaktivität und Selektivität von Übergangsmetallkatalysatoren und metallfreien Organokatalysatorsystemen eingegangen. Des Weiteren werden die Funktionsweisen dieser Katalysatoren insbesondere auf der Basis experimenteller mechanistischer Erkenntnisse beschrieben.
Controlled Covalent Functionalization of Thermally Reduced Graphene Oxide To Generate Defined Bifunctional 2D Nanomaterials
Authors: Faghani Abbas , Donskyi Ievgen S. , Fardin Gholami Mohammad , Ziem Benjamin , Lippitz Andreas , Unger Wolfgang E. S. , Böttcher Christoph , Rabe Jürgen P. , Haag Rainer , Adeli Mohsen
Published: February 2017

A controlled, reproducible, gram‐scale method is reported for the covalent functionalization of graphene sheets by a one‐pot nitrene [2+1] cycloaddition reaction under mild conditions. The reaction between commercially available 2,4,6‐trichloro‐1,3,5‐triazine and sodium azide with thermally reduced graphene oxide (TRGO) results in defined dichlorotriazine‐functionalized sheets. The different reactivities of the chlorine substituents on the functionalized graphene allow stepwise post‐modification by manipulating the temperature. This new method provides unique access to defined bifunctional 2D nanomaterials, as exemplified by chiral surfaces and multifunctional hybrid architectures.
Multidimensional SuFEx Click Chemistry: Sequential Sulfur(VI) Fluoride Exchange Connections of Diverse Modules Launched From An SOF4 Hub
Authors: Li Suhua , Wu Peng , Moses John E. , Sharpless K. Barry
Published: February 2017

Sulfur(VI) fluoride exchange (SuFEx) is a new family of click chemistry based transformations that enable the synthesis of covalently linked modules via SVI hubs. Here we report thionyl tetrafluoride (SOF4) as the first multidimensional SuFEx connector. SOF4 sits between the commercially mass‐produced gases SF6 and SO2F2, and like them, is readily synthesized on scale. Under SuFEx catalysis conditions, SOF4 reliably seeks out primary amino groups [R‐NH2] and becomes permanently anchored via a tetrahedral iminosulfur(VI) link: R−N=(O=)S(F)2. The pendant, prochiral difluoride groups R−N=(O=)SF2, in turn, offer two further SuFExable handles, which can be sequentially exchanged to create 3‐dimensional covalent departure vectors from the tetrahedral sulfur(VI) hub.
Catalytic Dearomatization of N‐Heteroarenes with Silicon and Boron Compounds
Authors: Park Sehoon , Chang Sukbok
Published: February 2017

Dearomatized N‐heterocycles are an important class of structural motifs for organic synthesis and chemical biology. The catalytic dearomative reduction of unactivated N‐heteroarenes using silicon and/or boron‐containing compounds as a reductant is one of the most straightforward alternatives to hydrogenation. However, thus far, there are few reported examples on the catalytic reduction of N‐heteroaromatic compounds with silane or borane reducing agents. This Review presents recent advances in the catalytic reduction of unactivated N‐heteroarenes by hydrosilanes, hydroboranes, silaboranes, and diboranes. The focus is on the chemical reactivity and selectivity of transition‐metal or metal‐free organocatalyst systems. In addition, the working modes of these catalysis will be described primarily on the basis of experimental mechanistic insight.
Heteroleptic (N‐heterocyclic carbene)–Pd–pyrazole (indazole) complexes: Synthesis, characterization and catalytic activities towards C–C and C–N cross‐coupling reactions
Authors: Yang Jin
Published: February 2017

Eight heteroleptic palladium complexes containing both N‐heterocyclic carbenes and NH‐heterocycle azoles (pyrazole and indazole) were synthesized and characterized, and their structures were unambiguously confirmed using single‐crystal X‐ray diffraction. Further investigation of the complexes as catalysts in the Suzuki–Miyaura reaction and Buchwald–Hartwig amination revealed good reactivities for aryl chlorides.
Facile fabrication of magnetic MoO2–Salen‐modified graphene‐based catalyst for epoxidation of alkenes
Authors: Li Zhifang , Yang Changlong , Ma Yuanyuan , Li Peng , Guan Jingqi , Kan Qiubin
Published: February 2017

A facile, green and efficient method for the immobilization of MoO2–Salen onto graphene hybridized with glucose‐coated magnetic Fe3O4 nanoparticles is proposed to fabricate a magnetic organic–inorganic hybrid heterogeneous RGO/Fe3O4@C‐Salen‐MoO2 catalyst for the epoxidation of cyclooctene and geraniol using tert‐butyl hydroperoxide or H2O2 as oxidant. Carbon‐coated Fe3O4 can improve the stability and add functional ─OH groups on the surface of Fe3O4. The fabricated composite exhibited good performance due to good dispersion of MoO2–Salen active sites. The catalyst can be easily separated from the reaction system using a permanent magnet and used three times without significantly losing its catalytic activity and selectivity.
Effects of microstructure design on aluminum surface hydrophobic and ice‐retarding properties
Authors: Chen K. , Sun T.
Published: February 2017

The poor mechanical strength of superhydrophobic surface limits its use in civil aviation. In this work, superhydrophobic surfaces with open and closed microstructure design were prepared, and their hydrophobicity and icephobicity over icing/de‐icing cycles were thoroughly studied. For all samples, contact angle decreased and contact angle hysteresis increased over time. However, surface with interconnected hollow honeycomb microstructure design kept its Cassie–Baxter state even after 20 times icing/de‐icing cycles, while surface with repeated individual post microscopic unit lost its superhydrophobicity only after six times icing/de‐icing cycles. The interconnected hollow honeycomb microstructure design strengthened surface mechanical strength by lowering the damage to microscopic unit. The freezing time for water droplet on surface with interconnected hollow honeycomb microstructure design was only slightly shortened over time. The difference in water/ice‐solid contact area for surfaces with different nano‐microscale design also led to the difference in wetting and ice‐retarding ability. Surface with interconnected hollow honeycomb microstructure design showed the strongest ice‐retarding ability followed by surface with interconnected hollow brick, ladder type, and triangle shape microstructure design. © 2017 Curtin University of Technology and John Wiley & Sons, Ltd.
A preliminary redating of the Holocene Roonka burials, south‐eastern Australia
Authors: LITTLETON JUDITH , PETCHEY FIONA , WALSHE KERYN , PATE F. DONALD
Published: February 2017

Roonka is one of the most complete excavations of an Aboriginal burial ground in south‐eastern Australia. The chronology of the site and the nature of its use have proven difficult to interpret. Previous dating and chronological interpretations of the site have emphasised a chronology of changing use and burial practices, but the nature of the site and the dates obtained do not clearly support these interpretations. We report on the direct dating of human bone from a further ten burials from the main excavation. In order to further investigate the cultural chronology set out by Pretty (1977), samples were selected to cover a range of burial types and preservation states. Comparison of these dates with the previous conventional dates and early AMS dates not only shows the impact of improving technology but demonstrates that multiple burial styles were in use contemporaneously. Moreover, the results suggest that use of the site may have been discontinuous. Consequently, interpretations that assume a chronological sequence for Roonka based on burial practice are not supported, while analyses based on a synchronic interpretation may ignore significant temporal change.
Molecular Oligogermanes and Related Compounds: Structure, Optical and Semiconductor Properties
Authors: Zaitsev Kirill V. , Tafeenko Viktor A. , Oprunenko Yuri F. , Kharcheva Anastasia V. , Zhanabil Zhaisan , Suleimen Yerlan , Lam Kevin , Zaitsev Vladimir B. , Zaitseva Anna V. , Zaitseva Galina S. , Karlov Sergey S.
Published: February 2017

The optical (UV/Vis absorbance, fluorescence in the solid state and in solution) and semiconducting properties of a number of di‐ and trigermanes as well as related silicon‐ and tin‐containing germanes, 1–6 ((p‐Tol)3GeGeMe3 (1), Ph3SnGe(SiMe3)3 (2), (C6F5)3GeGePh3 (3), (p‐Tol)3GeSiMe2SiMe3 (4), (p‐Tol)3GeGeMe2Ge(p‐Tol)3 (5), (p‐Tol)3GeSiMe2SiMe2Ge(p‐Tol)3 (6)) were investigated. Molecular structures of 5 and 6 were studied by X‐ray diffraction analysis. All compounds displayed luminescence properties. In addition, a band gap (of about 3.3 eV) was measured for compounds 1–6 showing that those molecules display semiconductor properties.
Severity of pedestrian injuries due to traffic crashes at signalized intersections in Hong Kong: a Bayesian spatial logit model
Authors: Xu Xuecai , Xie Siqi , Wong Sze Chun , Xu Pengpeng , Huang Helai , Pei Xin
Published: February 2017

The present study intended to (1) investigate the injury risk of pedestrian casualties involved in traffic crashes at signalized intersections in Hong Kong; (2) determine the effect of pedestrian volumes on the severity levels of pedestrian injuries; and (3) explore the role of spatial correlation in econometric crash‐severity models. The data from 1889 pedestrian‐related crashes at 318 signalized intersections between 2008 and 2012 were elaborately collected from the Traffic Accident Database System maintained by the Hong Kong Transport Department. To account for the cross‐intersection heterogeneity, a Bayesian hierarchical logit model with uncorrelated and spatially correlated random effects was developed. An intrinsic conditional autoregressive prior was specified for the spatial correlation term. Results revealed that (1) signalized intersections with greater pedestrian volumes generally exhibited a lower injury risk; (2) ignoring the spatial correlation potentially results in reduced model goodness‐of‐fit, an underestimation of variability and standard error of parameter estimates, as well as inconsistent, biased, and erroneous inference; (3) special attention should be paid to the following factors, which led to a significantly higher probability of pedestrians being killed or sustaining severe injury: pedestrian age greater than 65 years, casualties with head injuries, crashes that occurred on footpaths that were not obstructed/overcrowded, heedless or inattentive crossing, crashes on the two‐way carriageway, and those that occurred near tram or light‐rail transit stops. Copyright © 2017 John Wiley & Sons, Ltd.
Planning the optimal site, size, and feed of biogas plants in agricultural districts
Authors: Zema Demetrio Antonio
Published: February 2017

In agricultural districts, biogas production through anaerobic co‐digestion of residual biomasses is a sustainable way to valorize agro‐industry and livestock residues and integrate farm profits. Size and location of a biogas plant as well as co‐digestion substrate composition strictly depend on the substrate properties and availability within the rural district. The logistical substrate chain should be optimized to assure the right size and the maximum profitability of the planned biogas plant. A simple method is proposed to site a digester and choose its power output as well as to identify the optimal substrate blend, reducing the complexity of design and management operations. The method, requiring a reduced number of easy‐to‐survey input parameters, has been verified by its application to an agricultural district of southern Italy. If the planned plant is fed by a prevalent substrate from a single farm, the most economical power output is 300 kW. This size depends also on the Italian subsidy system to renewable energy. However, in the case of a centralized plant, supplied by a blend of substrates, the method gives the optimal plant location, based on the district barycenter, weighed by the biogas potential production of each farm. Secondly, the method suggests the annual amounts of the different substrates in the digester blend, maximizing the plant's annual profit and complying with technical‐economic constraints. Thirdly, the most economical power output of the plant is 480 kW. Finally, it indicates the related annual revenues, costs, and profits. The method can also be applied to other agricultural biomasses, such as ensiled crops or energy species available at a competitive cost, as are found in northern Europe. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd
Quantifizierung der Beanspruchung infolge der Temperatur und des Erddrucks bei Integralbrücken bis 30 m Länge
Authors: della Pietra Regina , Tue N. V.
Published: February 2017

Bei Integralbrücken ist die realistische Erfassung der Zwangbeanspruchungen und der Boden‐Bauwerks‐Interaktion von entscheidender Bedeutung für eine gelungene Bauwerksplanung. Im vorliegenden Beitrag werden wesentliche Ergebnisse zum Einfluss des Baugrunds auf die Schnittgrößen infolge von Temperaturänderung und des Erddrucks für Bauwerkslängen bis zu 30 m dargestellt und diskutiert. Damit werden mehr als 80 % der Brücken im Straßennetz von Österreich und Deutschland behandelt. Weiterhin wird der Frage nach dem Abbau der Zwangkraft im ULS und SLS nachgegangen. Auf diesen Ergebnissen basierend, werden Empfehlungen für die Planung und Bemessung von Integralbrücken bis zu 30 m Länge vorgeschlagen.
Effects of a Multicomponent Intervention to Improve Reading Fluency in Adult Students
Authors: Halldórsdóttir Lilja Ýr , Valdimarsdóttir Hildur , Arntzen Erik
Published: February 2017

The purpose of the present study was to use a delayed multiple probe design to evaluate the effects of a multicomponent intervention on reading fluency in three adult Norwegian university students. Prior to the study, all the participants had below average reading speed and one had the diagnosis dyslexia. The present procedure consisted of reading support, fluency aim, repeated reading, performance feedback, and error correction. Training involved daily sessions where a passage was read four times in a session or until a predetermined fluency aim was reached. Each participant read 10 passages during the intervention. Maintenance, generalization, and reading comprehension were tested to evaluate characteristics of fluent performance. The main findings indicate that reading fluency of all the participants improved. Results are discussed with regard to (i) conducting a multicomponent intervention; (ii) maintenance of the achieved improvements; (iii) possible effects on reading comprehension; and (iv) social validity of the study. Copyright © 2016 John Wiley & Sons, Ltd.
Exosome separation using microfluidic systems: size‐based, immunoaffinity‐based and dynamic methodologies
Authors: Yang Fang , Liao Xiangzhi , Tian Yuan , Li Guiying
Published: February 2017

Exosomes, nanovesicles secreted by most types of cells, exist in virtually all bodily fluids. Their rich nucleic acid and protein content make them potentially valuable biomarkers for noninvasive molecular diagnostics. They also show promise, after further development, to serve as a drug delivery system. Unfortunately, existing exosome separation technologies, such as ultracentrifugation and methods incorporating magnetic beads, are time‐consuming, laborious and separate only exosomes of low purity. Thus, a more effective separation method is highly desirable. Microfluidic platforms are ideal tools for exosome separation, since they enable fast, cost‐efficient, portable and precise processing of nanoparticles and small volumes of liquid samples. Recently, several microfluidic‐based exosome separation technologies have been studied. In this article, the advantages of the most recent technologies, as well as their limitations, challenges and potential uses in novel microfluidic exosome separation and collection applications is reviewed. This review outlines the uses of new powerful microfluidic exosome detection tools for biologists and clinicians, as well as exosome separation tools for microfluidic engineers. Current challenges of exosome separation methodologies are also described, in order to highlight areas for future research and development.
Light dilution via wavelength management for efficient high‐density photobioreactors
Authors: Ooms Matthew D. , Graham Percival J. , Nguyen Brian , Sargent Edward H. , Sinton David
Published: February 2017

The spectral distribution of light influences microalgae productivity; however, development of photobioreactors has proceeded largely without regard to spectral optimization. Here, we use monochromatic light to quantify the joint influence of path length, culture density, light intensity, and wavelength on productivity and efficiency in Synechococcus elongatus. The productivity of green light was ∼4× that of red at the highest levels of culture density, depth, and light intensity. This performance is attributed to the combination of increased dilution and penetration of this weakly absorbed wavelength over a larger volume fraction of the reactor. In contrast, red light outperformed other wavelengths in low‐density cultures with low light intensities. Low‐density cultures also adapted more rapidly to reduce absorption of longer wavelengths, allowing for prolonged cultivation. Taken together, these results indicate that, particularly for artificially lit photobioreactors, wavelength needs to be included as a critical operational parameter to maintain optimal performance. Biotechnol. Bioeng. 2017;114: 1160–1169. © 2017 Wiley Periodicals, Inc.
A Turn‐On Fluorescent Rhodamine‐acyl Hydrazide for Selective Detection of Cu2+ Ions
Authors: Yoon Jung Won , Jeong Hyuk , Lee Min Hee
Published: February 2017

We present a rhodamine‐based probe that can detect Cu2+ ions via Cu2+‐promoted hydrolysis in aqueous solutions. In solution, the probe is non‐fluorescent and colorless, but gives a strong fluorescence at 586 nm and shows a color change to pink on the addition of Cu2+ ions. We demonstrate that the rhodamine‐based probe undergoes Cu2+‐promoted hydrolysis with a moderate reaction time (within 3 min) and provides a fluorescence off–on change, even in the presence of other competitive metal ions. The rhodamine‐based probe shows a linear correlation between increasing fluorescence at 586 nm and the Cu2+ concentration, and can detect Cu2+ at nanomolar levels (10 nM) in CH3CN:H2O (v/v, 90:10).
Memory Errors in Alibi Generation: How an Alibi Can Turn Against Us
Authors: Crozier William E. , Strange Deryn , Loftus Elizabeth F.
Published: February 2017

Alibis play a critical role in the criminal justice system. Yet research on the process of alibi generation and evaluation is still nascent. Indeed, similar to other widely investigated psychological phenomena in the legal system – such as false confessions, historical claims of abuse, and eyewitness memory – the basic assumptions underlying alibi generation and evaluation require closer empirical scrutiny. To date, the majority of alibi research investigates the social psychological aspects of the process. We argue that applying our understanding of basic human memory is critical to a complete understanding of the alibi process. Specifically, we challenge the use of alibi inconsistency as an indication of guilt by outlining the “cascading effects” that can put innocents at risk for conviction. We discuss how normal encoding and storage processes can pose problems at retrieval, particularly for innocent suspects that can result in alibi inconsistencies over time. Those inconsistencies are typically misunderstood as intentional deception, first by law enforcement, affecting the investigation, then by prosecutors affecting prosecution decisions, and finally by juries, ultimately affecting guilt judgments. Put differently, despite the universal nature of memory inconsistencies, a single error can produce a cascading effect, rendering an innocent individual's alibi, ironically, proof of guilt. Copyright © 2017 John Wiley & Sons, Ltd.
Needle Terpenes as Chemotaxonomic Markers in Pinus: Subsections Pinus and Pinaster
Authors: Mitić Zorica S. , Jovanović Snežana Č. , Zlatković Bojan K. , Nikolić Biljana M. , Stojanović Gordana S. , Marin Petar D.
Published: February 2017

Chemical compositions of needle essential oils of 27 taxa from the section Pinus, including 20 and 7 taxa of the subsections Pinus and Pinaster, respectively, were compared in order to determine chemotaxonomic significance of terpenes at infrageneric level. According to analysis of variance, six out of 31 studied terpene characters were characterized by a high level of significance, indicating statistically significant difference between the examined subsections. Agglomerative hierarchical cluster analysis has shown separation of eight groups, where representatives of subsect. Pinaster were distributed within the first seven groups on the dendrogram together with P. nigra subsp. laricio and P. merkusii from the subsect. Pinus. On the other hand, the eighth group included the majority of the members of subsect. Pinus. Our findings, based on terpene characters, complement those obtained from morphological, biochemical, and molecular parameters studied over the past two decades. In addition, results presented in this article confirmed that terpenes are good markers at infrageneric level.
Insights from NMR Spectroscopy into the Conformational Properties of Man‐9 and Its Recognition by Two HIV Binding Proteins
Authors: Shahzad‐ul‐Hussan Syed , Sastry Mallika , Lemmin Thomas , Soto Cinque , Loesgen Sandra , Scott Danielle A. , Davison Jack R. , Lohith Katheryn , O'Connor Robert , Kwong Peter D. , Bewley Carole A.
Published: February 2017

Man9GlcNAc2 (Man‐9) present at the surface of HIV makes up the binding sites of several HIV‐neutralizing agents and the mammalian lectin DC‐SIGN, which is involved in cellular immunity and trans‐infections. We describe the conformational properties of Man‐9 in its free state and when bound by the HIV entry‐inhibitor protein microvirin (MVN), and define the minimum epitopes of both MVN and DC‐SIGN by using NMR spectroscopy. To facilitate the implementation of 3D 13C‐edited spectra to deconvolute spectral overlap and to determine the solution structure of Man‐9, we developed a robust expression system for the production of 13C,15N‐labeled glycans in mammalian cells. The studies reveal that Man‐9 interacts with HIV‐binding proteins through distinct epitopes and adopts diverse conformations in the bound state. In combination with molecular dynamics simulations we observed receptor‐bound conformations to be sampled by Man‐9 in the free state, thus suggesting a conformational selection mechanism for diverse recognition.
Lactosamine‐Based Derivatives as Tools to Delineate the Biological Functions of Galectins: Application to Skin Tissue Repair
Authors: Dion Johann , Deshayes Frédérique , Storozhylova Nataliya , Advedissian Tamara , Lambert Annie , Viguier Mireille , Tellier Charles , Dussouy Christophe , Poirier Françoise , Grandjean Cyrille
Published: February 2017

Galectins have been recognized as potential novel therapeutic targets for the numerous fundamental biological processes in which they are involved. Galectins are key players in homeostasis, and as such their expression and function are finely tuned in vivo. Thus, their modes of action are complex and remain largely unexplored, partly because of the lack of dedicated tools. We thus designed galectin inhibitors from a lactosamine core, functionalized at key C2 and C3′ positions by aromatic substituents to ensure both high affinity and selectivity, and equipped with a spacer that can be modified on demand to further modulate their physico‐chemical properties. As a proof‐of‐concept, galectin‐3 was selectively targeted. The efficacy of the synthesized di‐aromatic lactosamine tools was shown in cellular assays to modulate collective epithelial cell migration and to interfere with actin/cortactin localization.
Reversible dementia: subclinical seizure in early‐onset dementia
Authors: Tjong Elysia , McHugh William , Peng Yen‐Yi
Published: February 2017

Key Clinical Message

We report a case of early‐onset dementia with subclinical seizures. Aggressive seizure control improved the patient's cognition. Commonly, an EEG is only performed following overt behavioral seizures. Therefore, subclinical seizures tend to be underdiagnosed. Serial or extended EEG should be seriously considered in patients with early‐onset dementia.
Aerobic Oxidation of Alkynes to 1,2‐Diketones by Organic Photoredox Catalysis
Authors: Qin Hai‐Tao , Xu Xiao , Liu Feng
Published: February 2017

A method for the synthesis of 1,2‐diketones through the mild and metal‐free catalytic photooxygenation of alkynes is described. This reaction, using 9,10‐dicyanoanthracene as a catalytic sensitizer with/without biphenyl as a co‐sensitizer, readily furnished a variety of desired products upon visible‐light irradiation. Mechanistic studies indicated that a radical cation process might have been involved. This report provides the first examples of the transformation of alkynes via acetenyl radical cation intermediates, which have thus far not been explored in organic synthesis.
Mysterious Decomposition of Alkoxyphosphonium Chlorides: Postulated Involvement of the HCl2 Anion and Its Capture in the Solid State
Authors: Nikitin Kirill , Müller‐Bunz Helge , Muldoon Jimmy , Gilheany Declan G.
Published: February 2017

P‐Alkoxyphosphonium (AP) chlorides were generated by reacting P‐chlorophosphonium chlorides with alcohols. Their well‐known spontaneous Arbuzov‐type collapse leading to phosphine oxides was studied and its rate found to be dependent on a number of factors in an unexpected fashion: it is inversely proportional to the initial concentration and it shows strong dependence on the acidity of the media but is not very sensitive to the presence of base. To explain these observations, we evoke a self‐inhibition model with the formation of the less nucleophilic hydrodichloride anion HCl2 in solution. Detailed analysis of the kinetic data yields the association constant (K=3×102 m−1) of the putative HCl2 species in chloroform. Experimental observations for the collapse of highly enriched diastereomeric alkoxyphosphonium (DAP) chlorides are fully analogous to the achiral AP also implying the involvement of HCl2 anions. Moreover, crystallisation of a highly enriched DAP salt derived from (−)‐menthol furnished, for the first time, crystals of individual (RP)‐DAP hydrodichloride as confirmed by X‐ray diffractometry. Importantly, the P‐configuration and detailed conformation of the DAP moiety is in good agreement with DFT‐level computational results. The thermal collapse of (RP)‐DAP⋅HCl2 proceeds with complete retention of the P‐configuration furnishing the phosphine oxide of exceptional enantiomeric purity.
Cyclic Phosphopeptides to Rationalize the Role of Phosphoamino Acids in Uranyl Binding to Biological Targets
Authors: Starck Matthieu , Laporte Fanny A. , Oros Stephane , Sisommay Nathalie , Gathu Vicky , Solari Pier Lorenzo , Creff Gaëlle , Roques Jérôme , Den Auwer Christophe , Lebrun Colette , Delangle Pascale
Published: February 2017

The specific molecular interactions responsible for uranium toxicity are not yet understood. The uranyl binding sites in high‐affinity target proteins have not been identified yet and the involvement of phosphoamino acids is still an important question. Short cyclic peptide sequences, with three glutamic acids and one phosphoamino acid, are used as simple models to mimic metal binding sites in phosphoproteins and to help understand the mechanisms involved in uranium toxicity. A combination of peptide design and synthesis, analytical chemistry, extended X‐ray absorption fine structure (EXAFS) spectroscopy, and DFT calculations demonstrates the involvement of the phosphate group in the uranyl coordination sphere together with the three carboxylates of the glutamate moieties. The affinity constants measured with a reliable analytical competitive approach at physiological pH are significantly enhanced owing to the presence of the phosphorous moiety. These findings corroborate the importance of phosphoamino acids in uranyl binding in proteins and the relevance of considering phosphoproteins as potential uranyl targets in vivo.
Copper and Gold Cyclic (Alkyl)(amino)carbene Complexes with Sub‐Microsecond Photoemissions: Structure and Substituent Effects on Redox and Luminescent Properties
Authors: Romanov Alexander S. , Becker Ciaran R. , James Charlotte E. , Di Dawei , Credgington Dan , Linnolahti Mikko , Bochmann Manfred
Published: February 2017

Copper and gold halide and pseudo‐halide complexes stabilised by methyl‐, ethyl‐ and adamantyl‐substituted cyclic (alkyl)(amino)carbene (CAAC) ligands are mostly linear monomers in the solid state, without aurophilic Au⋅⋅⋅Au interactions. (Et2L)CuCl shows the highest photoluminescence quantum yield (PLQY) in the series, 70 %. The photoemissions of Me2L and Et2L copper halide complexes show S1→S0 fluorescence on the ns time scale, in agreement with theory, as well as a long‐lived emission. Monomeric (Me2L)CuNCS is a white emitter, whereas dimeric [(Et2L)Cu(μ‐NCS)]2 shows intense yellow emission with a photoluminescence (PL) quantum yield of 49 %. The reaction of (AdL)MCl (M=Cu or Au) with phenols ArOH (Ar=Ph, 2,6‐F2C6H3, 2,6‐Me2C6H3, 3,5‐tBu2C6H3, 2‐tBu‐5‐MeC6H3, 2‐pyridyl), thiophenol, or aromatic amines H2NAr′′ (Ar′=Ph, 3,5‐(CF3)2C6H3, C6F5, 2‐py) afforded the corresponding phenolato, thiophenolato and amido complexes. Although the emission wavelengths are only marginally affected by the ring substitution pattern, the PL intensities respond sensitively to the presence of substituents in the ortho or meta positions. In gold aryloxides, PL is controlled by steric factors, with strong luminescence in compounds with Au‐O‐C‐C torsion angles <50°. Calculations confirm the dependence of oscillator strength on the torsion angle, as well as the inter‐ligand charge transfer nature of the emission. The HOMO/LUMO energy levels were estimated based on first reduction and oxidation potentials.
Asymmetric Synthesis of 2,3‐Dihydrobenzofurans by a [4+1] Annulation Between Ammonium Ylides and In Situ Generated o‐Quinone Methides
Authors: Meisinger Nicole , Roiser Lukas , Monkowius Uwe , Himmelsbach Markus , Robiette Raphaël , Waser Mario
Published: February 2017

A highly enantio‐ and diastereoselective [4+1] annulation between in situ generated ammonium ylides and o‐quinone methides for the synthesis of a variety of 2,3‐dihydrobenzofurans has been developed. The key factors controlling the reactivity and stereoselectivity were systematically investigated by experimental and computational means and the energy profiles obtained provide a deeper insight into the mechanistic details of this reaction.
Microtubule‐regulating proteins and cAMP‐dependent signaling in neuroblastoma differentiation
Authors: Muñoz‐Llancao Pablo , de Gregorio Cristian , Las Heras Macarena , Meinohl Christopher , Noorman Kevin , Boddeke Erik , Cheng Xiaodong , Lezoualc'h Frank , Schmidt Martina , Gonzalez‐Billault Christian
Published: February 2017

Neurons are highly differentiated cells responsible for the conduction and transmission of information in the nervous system. The proper function of a neuron relies on the compartmentalization of their intracellular domains. Differentiated neuroblastoma cells have been extensively used to study and understand the physiology and cell biology of neuronal cells. Here, we show that differentiation of N1E‐115 neuroblastoma cells is more pronounced upon exposure of a chemical analog of cyclic AMP (cAMP), db‐cAMP. We next analysed the expression of key microtubule‐regulating proteins in differentiated cells and the expression and activation of key cAMP players such as EPAC, PKA and AKAP79/150. Most of the microtubule‐promoting factors were up regulated during differentiation of N1E‐115 cells, while microtubule‐destabilizing proteins were down regulated. We observed an increase in tubulin post‐translational modifications related to microtubule stability. As expected, db‐cAMP increased PKA‐ and EPAC‐dependent signalling. Consistently, pharmacological modulation of EPAC activity instructed cell differentiation, number of neurites, and neurite length in N1E‐115 cells. Moreover, disruption of the PKA‐AKAP interaction reduced these morphometric parameters. Interestingly, PKA and EPAC act synergistically to induce neuronal differentiation in N1E‐115. Altogether these results show that the changes observed in the differentiation of N1E‐115 cells proceed by regulating several microtubule‐stabilizing factors, and the acquisition of a neuronal phenotype is a process involving concerted although independent functions of EPAC and PKA.
Colloidal Metal Nanoparticles Prepared by Laser Ablation and their Applications
Authors: Zhang Jianming , Claverie Jerome , Chaker Mohamed , Ma Dongling
Published: February 2017

This review article highlights the recent advances of the synthesis and application of metal nanoparticles (NPs) fabricated via pulsed laser ablation in liquid (PLAL) phase and also introduces relevant NP formation mechanisms. Although wet‐chemical approaches have been well established to synthesize colloidal metal NPs with various components and structures, some inherent drawbacks, such as reaction residuals and/or contaminations, largely limit some of their applications. The PLAL method has recently been developed as an alternative approach and received increasing attention for colloidal NP preparation, without involving complicated chemical reactions. In certain cases, by using PLAL, ligand‐free and surface‐clean NPs can be obtained and well dispersed in liquid, leading to the formation of a “surface‐clean” NP dispersion. This unique feature renders PLAL‐synthesised metal NPs attractive candidates for many interesting applications in catalysis, biology, sensing, and clean energy generation and storage. We conclude this review by proposing several interesting research directions and future challenges, from PLAL fabrication to applications. We hope this review can serve as a good reference and help with the further development of PLAL‐NPs and their diverse applications.
SILAR BiOI‐Sensitized TiO2 Films for Visible‐Light Photocatalytic Degradation of Rhodamine B and 4‐Chlorophenol
Authors: Odling Gylen , Robertson Neil
Published: February 2017

BiOI nanoplates were deposited upon a film of TiO2 nanoparticles derived from a commercial source using a simple room temperature sequential ionic layer adsorption and reaction (SILAR) method. X‐ray diffraction, X‐ray photoelectron spectroscopy and electron microscopies have been used to confirm the crystal phase, chemical states of key elements and morphology of the BiOI nanoplate–TiO2 composites. Using both valence band X‐ray photoelectron spectroscopy and UV/Vis diffuse reflectance measurements the band structure of the composites is determined to be that of a type II heterojunction. Through initial screening of the photocatalytic activity of the SILAR‐modified films it was determined that five SILAR cycles are optimal in the photocatalytic degradation of rhodamine B. The visible‐light sensitisation effect of BiOI was then proven by examination of the photocatalytic degradation of the colourless organic pollutant 4‐chlorophenol, showing a large enhancement over an equivalent TiO2 film.