bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluorescent Probes Used for Measuring Intracellular Calcium
Authors: Oheim Martin
Published: August 2015

Calcium (Ca
2+
) is a ubiquitous messenger in many intracellular signalling cascades. With resting Ca
2+
concentrations around 100
nM
and peak amplitudes of Ca
2+
transients of the order of 10–100 μM, the specificity of the diverse Ca
2+
signals comes to a lesser degree from the affinities of the different biological Ca
2+
sensors and from the spatio‐temporal compartmentalisation of the Ca
2+
signal into subcellular nano‐ and microdomains. The measurement of such local and short‐lived Ca
2+
signals presents a major experimental challenge. Ca
2+
imaging with fluorescent indicators has initially involved synthetic small‐molecule chemical Ca
2+
indicators. While a large choice exists among molecules with different hues and Ca
2+
affinities and these molecules come in salt and ester forms for single‐cell or bulk loading, respectively, the subcellular targeting of Ca
2+
indicators and their long‐term use in live animals have remained problematic. The advent of genetically encoded Ca
2+
indicators that can be linked to different retention and targeting domains now permits the readout of local Ca
2+
signals, the targeting to different subcellular regions or cell types in intact tissue, the measurement of organelle Ca
2+
as well as long‐term recordings over months. For the detection of Ca
2+
nanodomains, hybrid organic–inorganic Ca
2+
nanobiosensors start to emerge as a promising alternative.

Key Concepts

Ca
2+
signals are local, both in space and time, and their spread and kinetics are shaped by the presence of endogeneous Ca
2+
‐binding molecules (Ca
2+
buffers).

Ca
2+
indicators are fluorescent exogeneous Ca
2+
buffers and as such distort the Ca
2+
signal to be measured.

Ca
2+
‐related fluorescence does not equal Ca
2+
concentration.

Genetically encoded Ca
2+
indicators are a powerful alternative to chemical small‐molecule organic indicators.

Measured Ca
2+
signals depend not only on the biological process studied and the properties of the fluorescent Ca
2+
indicator but also on the microscope and image acquisition parameters.

The measurement of local (rather than temporally and spatially averaged) Ca
2+
signals requires confinement of the dye volume, the fluorescence excitation volume, the fluorescence readout volume or a combination of these.
Glycolipid Presentation by
CD1
Authors: Layre Emilie , Mazurek Jolanta , Gilleron Martine
Published: August 2015

CD1
molecules constitute a family of nonpolymorphic,
MHC
class I‐like antigen‐presenting glycoproteins, which bind amphipathic lipid antigens and present them to T cells. These proteins are involved in presenting a broad range of self and foreign lipid antigens to variable T lymphocytes and natural killer T cells bearing a semi‐invariant T‐cell receptor (
iNKT
). It has become clear that the recognition of lipid antigens by T cells plays an important role in the detection and clearance of pathogens, immune response regulation and tissue surveillance.

Key Concepts

Self and microbial lipids and glycolipids are recognised by T cells.

Hydrophobic pockets of CD1 proteins allow lipid antigens to be loaded via their alkyl chains, while the hydrophilic part of the antigen is presented to T‐cell receptors.

CD1 proteins are non‐polymorphic and predominantly expressed on the surface of antigen‐presenting cells.

Glycolipids can be processed into smaller antigenic structures in the endosomal pathway.

CD1e, a soluble protein found in late endosomes, assists in lipid antigen editing and loading onto other CD1 proteins.

CD1‐restricted T cells express αβ or γδ TCR and are found in CD4
+
, CD8
+
or double‐negative T‐cell populations.

The frequency of autoreactive T cells is high among CD1‐restricted T cells.
Recent Advances and Prospects of Cathode Materials for Sodium‐Ion Batteries
Authors: Xiang Xingde , Zhang Kai , Chen Jun
Published: August 2015

Sodium‐ion batteries (SIBs) receive significant attention for electrochemical energy storage and conversion owing to their wide availability and the low cost of Na resources. However, SIBs face challenges of low specific energy, short cycling life, and insufficient specific power, owing to the heavy mass and large radius of Na+ ions. As an important component of SIBs, cathode materials have a significant effect on the SIB electrochemical performance. The most recent advances and prospects of inorganic and organic cathode materials are summarized here. Among current cathode materials, layered transition‐metal oxides achieve high specific energies around 600 mW h g−1 owing to their high specific capacities of 180–220 mA h g−1 and their moderate operating potentials of 2.7–3.2 V (vs Na+/Na). Porous Na3V2(PO4)3/C nanomaterials exhibit excellent cycling performance with almost 100% retention over 1000 cycles owing to their robust structural framework. Recent emerging cathode materials, such as amorphous NaFePO4 and pteridine derivatives show interesting electrochemical properties and attractive prospects for application in SIBs. Future work should focus on strategies to enhance the overall performance of cathode materials in terms of specific energy, cycling life, and rate capability with cationic doping, anionic substitution, morphology fabrication, and electrolyte matching.
Sulfonated Graphene as Cation‐Selective Coating: A New Strategy for High‐Performance Membrane Capacitive Deionization
Authors: Qian Bingqing , Wang Gang , Ling Zheng , Dong Qiang , Wu Tingting , Zhang Xu , Qiu Jieshan
Published: August 2015

Membrane capacitive deionization (MCDI) featuring both high electrosorption capacity and high energy efficiency holds promise for desalination. However, the large‐scale applications of MCDI are limited greatly by the high cost of commercial ion‐exchange membranes and the interfacial resistance. Here, a new strategy for high‐performance MCDI is established using sulfonated graphene (SG) as cation‐selective coating. A continuous ultrathin SG coating via self‐assembly is formed and attached tightly onto the surface of electrospun carbon nanofibers (CNFs) by a simple yet effective dip‐coating technique, yielding SG‐CNF composites with a hydrophilic surface, high electrochemical specific capacitance, and greatly reduced interfacial charge transfer rate. These result in significantly enhanced capacitive deionization performance in terms of both electrosorption capacity and charge efficiency. The SG coating shows excellent cation selectivity for an asymmetric cell with SG–CNFs as a cathode. The new approach may pave a way to novel micro‐MCDI, i.e. novel applications of functional graphene‐based materials for high‐performance, energy‐efficient, and cost‐effective desalination.
Facet‐Controlled Synthetic Strategy of Cu2O‐Based Crystals for Catalysis and Sensing
Authors: Shang Yang , Guo Lin
Published: August 2015

Shape‐dependent catalysis and sensing behaviours are primarily focused on nanocrystals enclosed by low‐index facets, especially the three basic facets ({100}, {111}, and {110}). Several novel strategies have recently exploded by tailoring the original nanocrystals to greatly improve the catalysis and sensing performances. In this Review, we firstly introduce the synthesis of a variety of Cu2O nanocrystals, including the three basic Cu2O nanocrystals (cubes, octahedra and rhombic dodecahedra, enclosed by the {100}, {111}, and {110} facets, respectively), and Cu2O nanocrystals enclosed by high‐index planes. We then discuss in detail the three main facet‐controlled synthetic strategies (deposition, etching and templating) to fabricate Cu2O‐based nanocrystals with heterogeneous, etched, or hollow structures, including a number of important concepts involved in those facet‐controlled routes, such as the selective adsorption of capping agents for protecting special facets, and the impacts of surface energy and active sites on reaction activity trends. Finally, we highlight the facet‐dependent properties of the Cu2O and Cu2O‐based nanocrystals for applications in photocatalysis, gas catalysis, organocatalysis and sensing, as well as the relationship between their structures and properties. We also summarize and comment upon future facet‐related directions.
Heterogeneous Distribution of Sodium for High Thermoelectric Performance of p‐type Multiphase Lead‐Chalcogenides
Authors: Yamini Sima Aminorroaya , Mitchell David R. G. , Gibbs Zachary M. , Santos Rafael , Patterson Vaughan , Li Sean , Pei Yan Zhong , Dou Shi Xue , Jeffrey Snyder G.
Published: August 2015

Despite the effectiveness of sodium as a p‐type dopant for lead chalcogenides, its solubility is shown to be very limited in these hosts. Here, a high thermoelectric efficiency of ≈2 over a wide temperature range is reported in multiphase quaternary (PbTe)0.65(PbS)0.25(PbSe)0.1 compounds that are doped with sodium at concentrations greater than the solubility limits of the matrix. Although these compounds present room temperature thermoelectric efficiencies similar to sodium doped PbTe, a dramatically enhanced Hall carrier mobility at temperatures above 600 K for heavily doped compounds results in significantly enhanced thermoelectric efficiencies at elevated temperatures. This is achieved through the composition modulation doping mechanism resulting from heterogeneous distribution of the sodium dopant between precipitates and the matrix at elevated temperatures. These results can lead to further advances in designing high performance multiphase thermoelectric materials with intrinsically heterogeneous dopant distributions.
Atypical Williams syndrome in an infant with complete atrioventricular canal defect
Authors: Ahrens‐Nicklas Rebecca C. , Reichert Sara L. , Zackai Elaine H. , Kaplan Paige B.
Published: August 2015

Williams‐Beuren Syndrome (WBS) is a well‐described microdeletion syndrome characterized by specific dysmorphic facial features, peripheral pulmonic stenosis, supravalvular aortic stenosis, hypercalcemia, feeding difficulties, gastroesophageal reflux, short stature, and specific intellectual disabilities (such as visual spatial problems). WBS is caused by 7q11.23 deletions that contain multiple genes known to contribute to the above phenotype. We report a neonate with a complete atrioventricular canal (CAVC) defect, an atypical cardiac lesion for WBS, and few typical phenotypic features of WBS, diagnosed at 20 days of life. © 2015 Wiley Periodicals, Inc.
A Polystyrene‐Bound Triphenylphosphine Gold(I) Catalyst for the Glycosylation of Glycosyl ortho‐Hexynylbenzoates
Authors: Zhu Yugen , Laval Stéphane , Tang Yu , Lian Gaoyan , Yu Biao
Published: August 2015

The efficacy of the heterogeneous polystyrene‐bound triphenylphosphine gold(I) catalyst 3 (PS‐[Ph3PAuINTf2]; PS=polystyrene; Tf=trifluoromethanesulfonyl) in the activation of glycosyl ortho‐hexynylbenzoates for glycosylation is demonstrated. The shelf‐stable catalyst 3 (and its precursor 2, PS‐[Ph3PAuICl]) were fully characterized by elemental analysis, X‐ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS), and scanning electron microscopy (SEM), and showed remarkable catalytic activities and recyclability in glycosylation reactions as well as in the skeletal rearrangement of the 1,6‐enyne 4. EDS analysis demonstrated that the phosphine ligand binds the gold strongly and prevents the leaching of the metal.
Disulfonimid‐katalysierte asymmetrische Reduktion von N‐Alkyliminen
Authors: Wakchaure Vijay N. , Kaib Philip S. J. , Leutzsch Markus , List Benjamin
Published: August 2015

Eine durch ein chirales Disulfonimid (DSI) katalysierte asymmetrische Reduktion von N‐Alkyliminen mit Hantzsch‐Estern als Wasserstoffquelle in Gegenwart von Boc2O wurde entwickelt. Diese Reaktion liefert Boc‐geschützte N‐Alkylamine mit ausgezeichneten Ausbeuten und Enantioselektivitäten. Die Methode toleriert viele verschiedene Alkylamine, was die Möglichkeit einer allgemeinen reduktiven Kreuzkupplung von Ketonen mit verschiedenen Aminen aufzeigt, und wurde in der Synthese der Wirkstoffe (S)‐Rivastigmin, NPS‐R‐568‐Hydrochlorid und (R)‐Fendiline angewendet.
Quantitative Measurement of Transmitters in Individual Vesicles in the Cytoplasm of Single Cells with Nanotip Electrodes
Authors: Li Xianchan , Majdi Soodabeh , Dunevall Johan , Fathali Hoda , Ewing Andrew G.
Published: August 2015

The quantification of vesicular transmitter content is important for studying the mechanisms of neurotransmission and malfunction in disease, and yet it is incredibly difficult to measure the tiny amounts of neurotransmitters in the attoliter volume of a single vesicle, especially in the cell environment. We introduce a novel method, intracellular vesicle electrochemical cytometry. A nanotip conical carbon‐fiber microelectrode was used to electrochemically measure the total content of electroactive neurotransmitters in individual nanoscale vesicles in single PC12 cells as these vesicles lysed on the electrode inside the living cell. The results demonstrate that only a fraction of the quantal neurotransmitter content is released during exocytosis. These data support the intriguing hypothesis that the vesicle does not open all the way during the normal exocytosis process, thus resulting in incomplete expulsion of the vesicular contents.
Conversion of Carbon Dioxide by Methane Reforming under Visible‐Light Irradiation: Surface‐Plasmon‐Mediated Nonpolar Molecule Activation
Authors: Liu Huimin , Meng Xianguang , Dao Thang Duy , Zhang Huabin , Li Peng , Chang Kun , Wang Tao , Li Mu , Nagao Tadaaki , Ye Jinhua
Published: August 2015

A novel CO2 photoreduction method, CO2 conversion through methane reforming into syngas (DRM) was adopted as an efficient approach to not only reduce the environmental concentration of the greenhouse gas CO2 but also realize the net energy storage from solar energy to chemical energy. For the first time it is reported that gold, which was generally regarded to be inactive in improving the performance of a catalyst in DRM under thermal conditions, enhanced the catalytic performance of Rh/SBA‐15 in DRM under visible‐light irradiation (1.7 times, CO2 conversion increased from 2100 to 3600 μmol g−1 s−1). UV/Vis spectra and electromagnetic field simulation results revealed that the highly energetic electrons excited by local surface plasmon resonances of Au facilitated the polarization and activation of CO2 and CH4 with thermal assistance. This work provides a new route for CO2 photoreduction and offers a distinctive method to photocatalytically activate nonpolar molecules.
Visible‐Light‐Driven Photoisomerization and Increased Rotation Speed of a Molecular Motor Acting as a Ligand in a Ruthenium(II) Complex
Authors: Wezenberg Sander J. , Chen Kuang‐Yen , Feringa Ben L.
Published: August 2015

Toward the development of visible‐light‐driven molecular rotary motors, an overcrowded alkene‐based ligand and the corresponding ruthenium(II) complex is presented. In our design, a 4,5‐diazafluorenyl coordination motif is directly integrated into the motor function. The photochemical and thermal isomerization behavior has been studied by UV/Vis and NMR spectroscopy. Upon coordination to a RuII bipyridine complex, the photoisomerization process can be driven by visible (λmax=450 nm) instead of UV light and furthermore, a large increase of the speed of rotation is noted. DFT calculations point to a contraction of the diazafluorenyl lower half upon metal‐coordination resulting in reduced steric hindrance in the “fjord region” of the molecule. Consequently, it is shown that metal‐ligand interactions can play an important role in the adjustment of both photophysical and thermodynamic properties of molecular motors.
Mononuclear Nonheme Iron(III)‐Iodosylarene and High‐Valent Iron‐Oxo Complexes in Olefin Epoxidation Reactions
Authors: Wang Bin , Lee Yong‐Min , Seo Mi Sook , Nam Wonwoo
Published: August 2015

High‐spin iron(III)‐iodosylarene complexes are highly reactive in the epoxidation of olefins, in which epoxides are formed as the major products with high stereospecificity and enantioselectivity. The reactivity of the iron(III)‐iodosylarene intermediates is much greater than that of the corresponding iron(IV)‐oxo complex in these reactions. The iron(III)‐iodosylarene species—not high‐valent iron(IV)‐oxo and iron(V)‐oxo species—are also shown to be the active oxidants in catalytic olefin epoxidation reactions. The present results are discussed in light of the long‐standing controversy on the one oxidant versus multiple oxidants hypothesis in oxidation reactions.
Chiral γ‐Lactams by Enantioselective Palladium(0)‐Catalyzed Cyclopropane Functionalizations
Authors: Pedroni Julia , Cramer Nicolai
Published: August 2015

Cyclopropanes fused to pyrrolidines are important structural features found in a number of marketed drugs and development candidates. Typically, their synthesis involves the cyclopropanation of a dihydropyrrole precursor. Reported herein is a complementary approach which employs a palladium(0)‐catalyzed CH functionalization of an achiral cyclopropane to close the pyrrolidine ring in an enantioselective manner. In contrast to aryl–aryl couplings, palladium(0)‐catalyzed CH functionalizations involving the formation of C(sp3)C(sp3) bonds of saturated heterocycles are very scarce. The presented strategy yields cyclopropane‐fused γ‐lactams from chloroacetamide substrates. A bulky Taddol phosphonite ligand in combination with adamantane‐1‐carboxylic acid as a cocatalyst provides the γ‐lactams in excellent yields and enantioselectivities.
Optical, electrical, and electrochemical properties of graphene based water soluble polyaniline composites
Authors: Meriga Venkanna , Valligatla Sreeramulu , Sundaresan Sivaprakash , Cahill Caroline , Dhanak Vinod R. , Chakraborty Amit K.
Published: August 2015

Polyaniline (PANI) is one of the most common polymers known for its conducting properties. However, poor water solubility limits its applications. In this work, PANI has been functionalized with sulfonic acid groups to produce sulfonated PANI (SPANI) offering excellent solubility in water. To compensate for the decrease of electrical conductivity due to functionalization, SPANI was combined with reduced graphene oxide (RGO) to form SPANI/RGO composites with interesting optical, thermal, and electrical properties. The composites have been characterized using X‐ray diffraction (XRD), field emission scanning electron microscopy, UV–vis absorption spectroscopy, Raman spectroscopy, Fourier‐transform infrared spectroscopy, X‐ray photoelectron spectroscopy, thermogravimetric analysis, cyclic voltammetry, and four probe electrical conductivity measurement. The SPANI/RGO composites show increased thermal stability, reduced optical band gap and improved electrochemical properties compared with the pure polymer. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2015,132, 42766.
Heterologous production of a feruloyl esterase from Pleurotus sapidus synthesizing feruloyl‐saccharide esters
Authors: Kelle Sebastian , Nieter Annabel , Krings Ulrich , Zelena Katerina , Linke Diana , Berger Ralf G.
Published: August 2015

The feruloyl esterase (FAE) gene EST1 from the basidiomycete Pleurotus sapidus was heterologously expressed in Escherichia coli and Pichia pastoris. Catalytically active recombinant Est1 was secreted using P. pastoris as a host. For expression in P. pastoris, the expression vector pPIC9K was applied. The EST1 gene was cloned with an N‐terminal α‐mating factor pre–pro sequence and expressed under the control of a methanol inducible alcohol oxidase 1 promotor. Est1 was purified to homogeneity using ion exchange and hydrophobic interaction chromatography. The recombinant Est1 showed optima at pH 5.0 and 50 °C, and released ferulic acid from saccharide esters and from the natural substrate destarched wheat bran. Substrate specificity profile and descriptor‐based analysis demonstrated unique properties, showing that Est1 did not fit into the current FAE classification model. Transferuloylation synthesis of feruloyl‐saccharide esters was proven for mono‐ and disaccharides.
Intensified fractionation of brewery yeast waste for the recovery of invertase using aqueous two‐phase systems
Authors: De León‐González Grecia , González‐Valdez José , Mayolo‐Deloisa Karla , Rito‐Palomares Marco
Published: August 2015

The potential recovery of high‐value products from brewery yeast waste confers value to this industrial residue. Aqueous two‐phase systems (ATPS) have demonstrated to be an attractive alternative for the primary recovery of biological products and are therefore suitable for the recovery of invertase from this residue. Sixteen different polyethylene glycol (PEG)–potassium phosphate ATPS were tested to evaluate the effects of PEG molecular weight (MW) and tie‐line length (TLL) upon the partition behavior of invertase. Concentrations of crude extract from brewery yeast waste were then varied in the systems that presented the best behaviors to intensify the potential recovery of the enzyme. Results show that the use of a PEG MW 400 g mol−1 system with a TLL of 45.0% (w/w) resulted in an invertase bottom phase recovery with a purification factor of 29.5 and a recovery yield of up to 66.2% after scaling the system to a total weight of 15.0 g. This represents 15.1 mg of invertase per mL of processed bottom phase. With these results, a single‐stage ATPS process for the recovery of invertase is proposed.
Now or Later? Attentional Processing and Intertemporal Choice
Authors: Franco‐Watkins Ana M. , Mattson Richard E. , Jackson Marc D.
Published: August 2015

The tendency to discount future prospects in lieu of smaller immediate outcomes is known as temporal discounting. The current work used eye‐tracking methodology to examine attentional processing to different elements of choice during an intertemporal decision task. Our findings reveal that those who tend to prefer the immediate option demonstrate attentional biases that were predictive of choice. When losses were at stake, selective attention biases also predicted unique variance in self‐report measures of risk taking, impulsivity, and self‐control beyond what was accounted for by a discounting parameter (k), a typical method for summarizing intertemporal choice data. Overall, our findings suggest that eye‐tracking measures of selective attention may allow for a better theoretical understanding of the mechanisms and processes involved in intertemporal choice. Copyright © 2015 John Wiley & Sons, Ltd.
Synergy between Palladium and Potassium Species for Efficient Activation of Carbon Monoxide in the Synthesis of Dimethyl Carbonate
Authors: Dong Yuanyuan , Shen Yongli , Zhao Yujun , Wang Shengping , Ma Xinbin
Published: August 2015

The front cover artwork for Issue 16/2015 is provided by Prof. Xinbin Ma and co‐workers from Tianjin University (P.R. China). The image shows the cooperative effect of Pd and K species for the activation of CO in the carbonylation of methyl nitrite to synthesize dimethyl carbonate. See the Full Paper itself at http://dx.doi.org/10.1002/cctc.201500317.
Comparison of Cyclic and Square Wave Voltammetry of Irreversible EC Mechanisms
Authors: Čižmek Lara , Komorsky‐Lovrić Šebojka , Lovrić Milivoj
Published: August 2015

A theoretical model of EC mechanism that consists of reversible electrode reaction and totally irreversible chemical reaction is developed for cyclic and square wave voltammetry. Critical kinetic parameters are calculated and their application for the determination of rate constant of chemical reaction is demonstrated. It is shown that this constant may be used for the estimation of enhanced activity of antioxidants.
Far‐Red Emitting Fluorescent Dyes for Optical Nanoscopy: Fluorinated Silicon–Rhodamines (SiRF Dyes) and Phosphorylated Oxazines
Authors: Kolmakov Kirill , Hebisch Elke , Wolfram Thomas , Nordwig Lars A. , Wurm Christian A. , Ta Haisen , Westphal Volker , Belov Vladimir N. , Hell Stefan W.
Published: August 2015

Far‐red emitting fluorescent dyes for optical microscopy, stimulated emission depletion (STED), and ground‐state depletion (GSDIM) super‐resolution microscopy are presented. Fluorinated silicon–rhodamines (SiRF dyes) and phosphorylated oxazines have absorption and emission maxima at about λ≈660 and 680 nm, respectively, possess high photostability, and large fluorescence quantum yields in water. A high‐yielding synthetic path to introduce three aromatic fluorine atoms and unconventional conjugation/solubilization spacers into the scaffold of a silicon–rhodamine is described. The bathochromic shift in SiRF dyes is achieved without additional fused rings or double bonds. As a result, the molecular size and molecular mass stay quite small (<600 Da). The use of the λ=800 nm STED beam instead of the commonly used one at λ=750–775 nm provides excellent imaging performance and suppresses re‐excitation of SiRF and the oxazine dyes. The photophysical properties and immunofluorescence imaging performance of these new far‐red emitting dyes (photobleaching, optical resolution, and switch‐off behavior) are discussed in detail and compared with those of some well‐established fluorophores with similar spectral properties.
Ruthenium(II) and Osmium(II) Vinyl Complexes as Highly Sensitive and Selective Chromogenic and Fluorogenic Probes for the Sensing of Carbon Monoxide in Air
Authors: Toscani Anita , Marín‐Hernández Cristina , Moragues María E. , Sancenón Félix , Dingwall Paul , Brown Neil J. , Martínez‐Máñez Ramón , White Andrew J. P. , Wilton‐Ely James D. E. T.
Published: August 2015

The detection of carbon monoxide in solution and air has been achieved using simple, inexpensive systems based on the vinyl complexes [M(CHCHR)Cl(CO)(BTD)(PPh3)2] (R=aryl, BTD=2,1,3‐benzothiadiazole). Depending on the nature of the vinyl group, chromogenic and fluorogenic responses signalled the presence of this odourless, tasteless, invisible, and toxic gas. Solutions of the complexes in CHCl3 underwent rapid change between easily differentiated colours when exposed to air samples containing CO. More significantly, the adsorption of the complexes on silica produced colorimetric probes for the naked‐eye detection of CO in the gas phase. Structural data for key species before and after the addition of CO were obtained by means of single X‐ray diffraction studies. In all cases, the ruthenium and osmium vinyl complexes studied showed a highly selective response to CO with exceptionally low detection limits. Naked‐eye detection of CO at concentrations as low as 5 ppb in air was achieved with the onset of toxic levels (i.e., 100 ppm), thus resulting in a remarkably clear colour change. Moreover, complexes bearing pyrenyl, naphthyl, and phenanthrenyl moieties were fluorescent, and greater sensitivities were achieved (through turn‐on emission fluorescence) in the presence of CO both in solution and air. This behaviour was explored computationally using time‐dependent density functional theory (TDDFT) experiments. In addition, the systems were shown to be selective for CO over all other gases tested, including water vapour and common organic solvents. Supporting the metal complexes on cellulose strips for use in an existing optoelectronic device allows numerical readings for the CO concentration to be obtained and provision of an alarm system.
Solvatochromism, Reversible Chromism and Self‐Assembly Effects of Heteroatom‐Assisted Aggregation‐Induced Enhanced Emission (AIEE) Compounds
Authors: Niu Caixia , You Ying , Zhao Liu , He Dacheng , Na Na , Ouyang Jin
Published: August 2015

Two compounds, 9,10‐bis[2‐(quinolyl)vinyl]anthracene (BQVA) and 9,10‐bis[2‐(naphthalen‐2‐yl)vinyl]anthracene (BNVA), have been synthesised and investigated. Both of them have aggregation‐induced enhanced emission (AIEE) properties. Heteroatom‐assisted BQVA shows solvatochromism, reversible chromism properties and self‐assembly effects. When increasing the solvent polarities, the green solution of BQVA turns to orange with a redshift of the fluorescence emission wavelengths from λ=527 to 565 nm. Notably, BQVA exhibits reversible chromism properties, including mechano‐ and thermochromism. The as‐prepared BQVA powders show green fluorescence (λem=525 nm) and the colour can turn into orange (λem=573 nm) after grinding. Interestingly, the orange colour can return at high temperature. Based on these reversible chromism properties, a simple and convenient erasable board has been designed. Different from BQVA, non‐heteroatom‐assisted BNVA has no clear chromic processes. The results obtained from XRD, differential scanning calorimetry, single‐crystal analysis and theoretical calculations indicate that the chromic processes depend on the heteroatoms in BQVA. Additionally, BQVA also exhibits excellent self‐assembly effects in different solvents. Homogeneous nanospheres are formed in mixtures of tetrahydrofuran and water, which are then doped into silica nanoparticles and treated with 3‐aminopropyltriethoxysilane to give amino‐functionalised nanoparticles (BQVAAFNPs). The BQVAAFNPs could be used to stain protein markers in polyacrylamide gel electrophoresis.
The Solid Solution Sr1−xBaxGa2: Substitutional Disorder and Chemical Bonding Visited by NMR Spectroscopy and Quantum Mechanical Calculations
Authors: Pecher Oliver , Mausolf Bernhard , Lamberts Kevin , Oligschläger Dirk , Niewieszol (née Merkens) Carina , Englert Ulli , Haarmann Frank
Published: August 2015

Complete miscibility of the intermetallic phases (IPs) SrGa2 and BaGa2 forming the solid solution Sr1−xBaxGa2 is shown by means of X‐ray diffraction, thermoanalytical and metallographic studies. Regarding the distances of Sr/Ba sites versus substitution degree, a model of isolated substitution centres (ISC) for up to 10 % cation substitution is explored to study the influence on the Ga bonding situation. A combined application of NMR spectroscopy and quantum mechanical (QM) calculations proves the electric field gradient (EFG) to be a sensitive measure of different bonding situations. The experimental resolution is boosted by orientation‐dependent NMR on magnetically aligned powder samples, revealing in first approximation two different Ga species in the ISC regimes. EFG calculations using superlattice structures within periodic boundary conditions are in fair agreement with the NMR spectroscopy data and are discussed in detail regarding their application on disordered IPs.
A Combined Experimental and Theoretical Study on the Stereodynamics of Monoaza[5]helicenes: Solvent‐Induced Increase of the Enantiomerization Barrier in 1‐Aza‐[5]helicene
Authors: Caronna Tullio , Mele Andrea , Famulari Antonino , Mendola Daniele , Fontana Francesca , Juza Markus , Kamuf Matthias , Zawatzky Kerstin , Trapp Oliver
Published: August 2015

Helicenes and heterohelicenes are attractive compounds with great potential in materials sciences to be used in optoelectronics as ligand backbones in enantioselective catalysis and as chiral sensors. The properties of these materials are related to the stereodynamics of these helical chiral compounds. However, little is known about features controlling stereodynamics in helicenes; in particular, for heterohelicenes the position of the heteroatom could be relevant in this respect. Herein the complete stereodynamic characterization of monoaza[5]helicenes is shown by enantioselective dynamic HPLC and DFT calculations. At variance with previous theoretical calculations, 1‐aza[5]helicene shows a surprisingly high enantiomerization barrier, which is triggered by specific solvent interactions.
Experimental and numerical modelling of arsenic adsorption in fixed‐bed dynamic columns packed with atlantic cod fish scales
Authors: Rahaman M. Saifur , Omi Farah Rahman , Basu Avijit
Published: August 2015

The removal of arsenic ions from aqueous streams using the scales of Atlantic Cod species (Gadus morhua) involves adsorption and possible precipitation of its constituents, and is dependent on the number of available surface excess sites per mass unit of the bio‐adsorbent. In modelling the adsorption behaviour of metal ions, the numerical code based on surface excess theory was applied using a two‐dimensional mass transport model for determination of breakthrough characteristics in dynamic packed bed columns. Numerical simulation data, using surface excess theory, demonstrate a reasonably close agreement with experimental results from dynamic column tests. Parameters such as porosity, selectivity, flow rate, and adsorption coefficient contribute significantly to the variation in breakthrough time intervals associated with dynamic packed bed adsorption columns.
Elastic component‐based applications in PaaS clouds
Authors: Pokahr Alexander , Braubach Lars
Published: August 2015

Elasticity is the capability of an application to adapt its resource usage to the current workload of the system. Existing platform‐as‐a‐service (PaaS) solutions concentrate on web applications and do not support elasticity for other kinds of applications. To change this, in this paper, the vision and partial implementation for a component‐based PaaS cloud is proposed consisting of a programming model and an autonomic manager for safeguarding non‐functional application requirements. To illustrate this vision, the paper focuses on two key features of a PaaS infrastructure, the scale‐out of services and the on‐demand deployment of application resources. The former allows for increasing the performance by distributing service calls among several service providers working in parallel, and the latter refers to the automatic packaging and transfer of needed deployment units. It will be shown how these aspects have been solved within the Jadex PaaS cloud infrastructure. Both concepts have been validated using an application scenario, which highlights the advantages of automatic service scaling and deployment for developers and users. Copyright © 2015 John Wiley & Sons, Ltd.
A generic API for load balancing in distributed systems for big data management
Authors: Antoine Maeva , Pellegrino Laurent , Huet Fabrice , Baude Françoise
Published: August 2015

Distributed systems for big data management very often face the problem of load imbalance among nodes. To address this issue, there exist almost as many load balancing strategies as there are different systems. When designing a scalable distributed system geared towards handling large amounts of information, it is often not so easy to anticipate which kind of strategy will be the most efficient to maintain adequate performance regarding response time, scalability, and reliability at any time. Based on this observation, we describe a generic API to implement and experiment any strategy independently from the rest of the code, prior to a definitive choice for instance. We then show how existing load balancing strategies used by famous systems could be implemented with this API. We also present how this work has helped us implement load balancing on our distributed system and modify the behavior of our strategy in a few lines of code. This led us to easily perform various experiments to determine the most efficient scheme for our system. This paper is an extension to our work presented at Workshop on Parallel and Distributed Computing for Big Data Applications (WPBA) 2014. We detail here more experiments and extend the use of the API to a broad class of big data storage systems. Copyright © 2015 John Wiley & Sons, Ltd.
Effect of Erbium on the Photocatalytic Activity of TiO2/Ag Nanocomposites under Visible Light Irradiation
Authors: Prakash Natarajan , Karthikeyan Rajan , Thangaraju Dheivasigamani , Navaneethan Mani , Arivanandhan Mukannan , Koyama Tadanobu , Hayakawa Yasuhiro
Published: August 2015

Erbium co‐doped TiO2/Ag catalysts are synthesized by using a simple, one‐step solvothermal method and characterized by X‐ray diffraction, field‐emission scanning electron microscopy, transmission electron microscopy, Raman analysis, X‐ray photoelectron spectroscopy, and diffuse reflectance spectroscopy. The catalysts exhibit anatase crystal structures with increased visible light absorption compared with pure TiO2. Enhanced photocatalytic activity is observed with Er co‐doped TiO2/Ag nanocomposites for Rhodamine B degradation under visible light irradiation. The photocatalytic activity of 1 % Er co‐doped TiO2/Ag is much higher than that of TiO2/Ag, TiO2/Er, pure TiO2, and commercial Degussa P25. The kinetics of the degradation process are studied and the pseudo‐first‐order rate constant (k) and half‐life time (t1/2) of the reaction are calculated. The enhanced activity might be accredited to the efficient separation of electron–hole pairs by silver and higher visible light absorption of TiO2 induced by Er.
Ag on Pt(111): Changes in Electronic and CO Adsorption Properties upon PtAg/Pt(111) Monolayer Surface Alloy Formation
Authors: Diemant Thomas , Schüttler Konstantin M. , Behm R. Jürgen
Published: August 2015

The electronic and chemical (adsorption) properties of bimetallic Ag/Pt(111) surfaces and their modification upon surface alloy formation, that is, during intermixing of Ag and Pt atoms in the top atomic layer upon annealing, were studied by X‐ray photoelectron spectroscopy (XPS) and, using CO as probe molecule, by temperature‐programmed desorption (TPD) and infrared reflection absorption spectroscopy (IRRAS), respectively. The surface alloys are prepared by deposition of sub‐monolayer Ag amounts on a Pt(111) surface at room temperature, leading to extended Ag monolayer islands on the substrate, and subsequent annealing of these surfaces. Surface alloy formation starts at ≈600–650 K, which is evidenced by core‐level shifts (CLSs) of the Ag(3d5/2) signal. A distinct change of the CO adsorption properties is observed when going to the intermixed PtAg surface alloys. Most prominently, we find the growth of a new desorption feature at higher temperature (≈550 K) in the TPD spectra upon surface alloy formation. This goes along with a shift of the COad‐related IR bands to lower wave number. Surface alloy formation is almost completed after heating to 700 K.
Probabilistic routing algorithm based on contact duration and message redundancy in delay tolerant network
Authors: Yu Chen , Tu Zhongqiu , Yao Dezhong , Lu Feng , Jin Hai
Published: August 2015

The Delay Tolerant Network (DTN) is a novel Wireless Sensor Network architecture for an opportunistic network environment, in which environment end‐to‐end connection cannot be set up constantly between source and destination nodes pairs. In this paper, we have proposed a novel routing algorithm based on a hybrid of message delivery probability and message redundancy to reduce the communication overhead while keeping the high message delivery ratio. In this algorithm, the message delivery probability is calculated by the combined impact of meeting frequency and length of contact duration. Further, the maximum number of copies of the message is designated in the source node, and the forwarding task of message copies is assigned to relay nodes based on the pattern of a binary tree, so that multi‐path parallel transmission can be implemented on message forwarding. Simulated results showed that the proposed routing algorithm can achieve a higher efficiency of message delivery than the related existing routing algorithms and it can also reduce the communication overhead significantly in general DTNs. Copyright © 2015 John Wiley & Sons, Ltd.
Performance evaluation of HDAF relaying systems for pilot and data symbol burst transmission over quasi‐static Rayleigh fading channels
Authors: Lim Sungmook , Ko Kyunbyoung
Published: August 2015

This paper analyzes averaged symbol error probabilities of burst transmission consisting of pilot and data symbols for hybrid adaptive decode‐or‐amplify‐forward (HDAF) relaying systems. Under the assumption of quasi‐static Rayleigh fading channels with independent and non‐identically distribution, we consider a channel estimation scheme based on pilot symbols and show how channel estimation error affects received signal‐to‐noise ratio (SNR) and symbol error probability (SEP). Firstly, all the possible detection error‐events are presented for all the relay nodes, and their probabilities are derived as forms related with data symbol burst transmission. For the given error event, we analyze the conditional SEP as an exact form and then, the averaged SEP (ASEP) is approximately derived as a closed‐form. The simulation results verify that our derived ASEP expression is accurate over all the regions of SNR. Utilizing the proposed expressions, we can evaluate ASEP performance of HDAF relay systems easily and fast. Copyright © 2015 John Wiley & Sons, Ltd.
System analysis of Neo‐Gothic vaults / Systemanalyse neugotischer Gewölbe
Authors: Piehler Jens , Hanse Michael , Kapphahn Gerd
Published: August 2015

From the middle of the 19th century until the beginning of World War I, many buildings were built in the Neo‐Gothic style. In this period, Gothic elements were built regarding the former needs to save material. These lightweight and thin vaults are often relatively fragile support systems. They tend to show systemic damages in the form of significant crack patterns in the vault caps and arches. In the research project Preservation of Neo‐Gothic vault structures, typical damages of Neo‐Gothic vaulted structures are analyzed with the objective to find sustainable and rehabilitative measures. In this context, since 2011, numerical and experimental studies have been carried out on a reference structure. Measured values of a 3D laser scanning, including all the imperfections of the structure, provide the basis of the geometry model, created for the finite element simulation. The system behavior was studied experimentally in the non‐critical load range with a load test for the calibration of this numerical model. In this paper, the project framework as well as the implementation and the evaluation of the load test are presented. In further papers, the transfer of the geodetic measurement data to the numerical model and the consideration of the load test results within a realistically finite element simulation will be addressed.
Win over faculty members and influence campus culture
Authors: Hope Joan
Published: August 2015

ST. PAUL, MINN. — Coming from a social justice background, Katheryne Staeger‐Wilson has sometimes been frustrated that her role has seemed to be about gatekeeping, ensuring minimum compliance, and protecting the university rather than helping students. She's director of the Disability Resource Center at Missouri State University. She took steps to change her role.
Induced responses to grazing by an insect herbivore (Acentria ephemerella) in an immature macrophyte (Myriophyllum spicatum): an isotopic study
Authors: Rothhaupt Karl‐Otto , Fornoff Felix , Yohannes Elizabeth
Published: August 2015

While the mechanisms by which adult terrestrial plants deploy constitutive and induced responses to grazing pressure are well known, the means by which young aquatic plants defend themselves from herbivory are little studied. This study addresses nitrogen transport in the aquatic angiosperm Myriophyllum spicatum in response to herbivore exposure. Nitrogen tracers were used to monitor nitrogen uptake and reallocation in young plants in response to grazing by the generalist insect herbivore Acentria ephemerella. Total nitrogen content (N%) and patterns of nitrogen uptake and allocation (δ15N) were assessed in various plant tissues after 24 and 48 h. Following 24 h exposure to herbivore damage (Experiment 1), nitrogen content of plant apices was significantly elevated. This rapid early reaction may be an adaptation allowing the grazer to be sated as fast as possible, or indicate the accumulation of nitrogenous defense chemicals. After 48 h (Experiment 2), plants' tips showed depletion in nitrogen levels of ca. 60‰ in stem sections vulnerable to grazing. In addition, nitrogen uptake by grazed and grazing‐prone upper plant parts was reduced and nutrient allocation into the relatively secure lower parts increased. The results point to three conclusions: (1) exposure to an insect herbivore induces a similar response in immature M. spicatum as previously observed in mature terrestrial species, namely a rapid (within 48 h) reduction in the nutritional value (N%) of vulnerable tissues, (2) high grazing intensity (100% of growing tips affected) did not limit the ability of young plants to induce resistance; and (3) young plants exposed to herbivory exhibit different patterns of nutrient allocation in vulnerable and secure tissues. These results provide evidence of induced defense and resource reallocation in immature aquatic macrophytes which is in line with the responses shown for mature aquatic macrophytes and terrestrial plants.
Multifunctional Hybrid Silica Nanoparticles with a Fluorescent Core and Active Targeting Shell for Fluorescence Imaging Biodiagnostic Applications
Authors: Santiago Ana M. , Ribeiro Tânia , Rodrigues Ana S. , Ribeiro Bruno , Frade Raquel F. M. , Baleizão Carlos , Farinha José Paulo S.
Published: August 2015

We prepared hybrid nanoparticles with a brightly fluorescent silica core and a biocompatible thermoresponsive polymer shell containing tumor‐targeting folic acid (FA) groups. The silica core has a perylenediimide fluorescent dye anchored covalently to the structure for traceability and bioimaging applications. The polymeric shell was synthesized by reversible addition–fragmentation chain‐transfer (RAFT) polymerization to guarantee the homogeneous size of the particle shell. The shell is composed of copolymer chains with one block of oligo(ethylene glycol)methacrylate and 2‐(2′‐methoxyethoxy)ethylmethacrylate with another block of the reactive monomer N‐acryloxysuccinimide (NAS). The NAS groups were used to covalently attach a large amount of amino‐functionalized FA to the particle shells to provide active targeting properties towards cancer cells and tissues. The targeting capability of the folate‐containing nanoparticles was evaluated against NCI‐H460 tumor cells, which overexpress folate receptors. The nanoparticles with FA show a higher uptake efficiency compared to that of the equivalent nanoparticles without FA. This result validates the imaging capabilities and active targeting efficiency of our nanoparticles, an important step towards the goal of developing vehicles for precision drug delivery systems that combine therapeutic and diagnostic (theranostic) functionalities with large drug payloads, active targeting, and stimuli‐activated drug release.
Methylmercury biomagnification in an Arctic pelagic food web
Authors: Ruus Anders , Øverjordet Ida B. , Braaten Hans Fredrik V. , Evenset Anita , Christensen Guttorm , Heimstad Eldbjørg S. , Gabrielsen Geir W. , Borgå Katrine
Published: August 2015

Mercury (Hg) is a toxic element that enters the biosphere from natural and anthropogenic sources, and emitted gaseous Hg enters the Arctic from lower latitudes by long-range transport. In aquatic systems, anoxic conditions favor the bacterial transformation of inorganic Hg to methylmercury (MeHg), which has a greater potential for bioaccumulation than inorganic Hg and is the most toxic form of Hg. The main objective of the present study was to quantify the biomagnification of MeHg in a marine pelagic food web, comprising species of zooplankton, fish, and seabirds, from the Kongsfjorden system (Svalbard, Norway), by use of trophic magnification factors. As expected, tissue concentrations of MeHg increased with increasing trophic level in the food web, though at greater rates than observed in several earlier studies, especially at lower latitudes. There was strong correlation between MeHg and total Hg concentrations through the food web as a whole. The concentration of MeHg in kittiwake decreased from May to October, contributing to seasonal differences in trophic magnification factors. The ecology and physiology of the species comprising the food web in question may have a large influence on the magnitude of the biomagnification. A significant linear relationship was also observed between concentrations of selenium and total Hg in birds but not in zooplankton, suggesting the importance of selenium in Hg detoxification for individuals with high Hg concentrations. Environ Toxicol Chem 2015;34:2636–2643. © 2015 SETAC