bluuebunny/crossref_metadata_2025 huggingface dataset:
Decoration of Gold Nanoparticles by a Double‐Armed Calix[4]pyrrole: A Receptor‐Decorated Nanoensemble for Anion Sensing and Extraction
Authors: Sokkalingam Punidha , Hong Seong‐Jin , Aydogan Abdullah , Sessler Jonathan L. , Lee Chang‐Hee
Published: April 2013

Gold nanoparticles decorated with a double‐armed, deep‐cavity calix[4]pyrrole were prepared and fully characterized. Transmission electron microscopy imaging revealed that the average diameter of the particles was approximately 4 nm both before and after attachment of the receptor to the surface. The calix[4]pyrrole‐functionalized nanoparticles exhibited highly elevated sensing behavior (approximately 1000 times in dichloromethane) relative to its monomeric congener while maintaining its guest selectivity. The receptor–nanoparticle conjugate (nanoreceptor) showed significant aggregation upon addition of the biphenolate anion, an effect ascribed to anion‐mediated interparticle linking. The receptor–nanoparticle conjugate is also capable of extracting the fluoride anion (as its tetrabutylammonium salt) from an aqueous layer to an organic medium. Control experiments revealed that this extraction is not possible when using the analogous monomeric receptor.
Attosecond Nuclear Dynamics in the Ammonia Cation: Relation between High‐Harmonic and Photoelectron Spectroscopies
Authors: Kraus Peter Michael , Wörner Hans Jakob
Published: April 2013

We report measurements of the umbrella motion in the ammonia cation on the attosecond time scale. The motion is prepared by strong‐field ionization and probed by photorecombination through the process of high‐harmonic generation. Performing such measurements at multiple wavelengths (0.8, 1.44, 1.8 μm) enables us to follow the nuclear dynamics over a broad temporal range (0.8–3.8 fs). The intensity of the driving field is found to have a significant impact on the observed dynamics through the vibrational‐state dependence of the strong‐field ionization rates. We derive a general model that includes these effects and establishes a new link between high‐harmonic spectroscopy and classical photoelectron spectroscopy. Our model reproduces the observed dynamics and their dependence on the intensity of the driving field. Moreover, the model predicts much richer nuclear dynamics on the few‐fs timescale than most previous theories. The newly predicted features are shown to reflect the quantized vibronic level structure of the molecular cation.
Incorporation of Hydrogen‐Bonding Functionalities into the Second Coordination Sphere of Iron‐Based Water‐Oxidation Catalysts
Authors: Hoffert Wesley A. , Mock Michael T. , Appel Aaron M. , Yang Jenny Y.
Published: April 2013

Energy storage and conversion schemes based on environmentally benign chemical fuels will require the discovery of faster, cheaper, and more robust catalysts for the oxygen‐evolution reaction (OER). Although the incorporation of pendant bases into molecular catalysts for hydrogen production and utilization has led to enhanced turnover frequencies, the analogous incorporation of pendant bases into molecular catalysts for water oxidation has received little attention. Herein, the syntheses, structures, and catalytic activities of new iron complexes with pendant bases are reported. Of these new complexes, [Fe(L1)]2+ {L1 = N,N′‐dimethyl‐N,N′‐bis(pyridazin‐3‐ylmethyl)ethane‐1,2‐diamine} is the most active catalyst. Initial turnover frequencies of 141 and 24 h–1 were measured by using ceric ammonium nitrate at pH 0.7 and sodium periodate at pH 4.7, respectively. These results suggest that the incorporation of pendant bases into molecular catalysts for water oxidation might be an effective strategy that can be considered in the development of new catalysts for the OER, but will require the careful balance of many factors.
Growth and Characterization of Centimeter‐Sized Ba2LaFeNb4O15 Crystals from High‐Temperature Solution under a Controlled Atmosphere
Authors: Albino Marjorie , Veber Philippe , Castel Elias , Velázquez Matias , Schenk Kurt , Chapuis Gervais , Lahaye Michel , Pechev Stanislav , Maglione Mario , Josse Michaël
Published: April 2013

Centimeter‐sized single crystals of Ba2LaFeNb4O15 were grown from a high‐temperature solution by using LiBO2 flux and a sealed platinum assembly. The obtained single crystals display the same physical properties as their ceramic counterparts. A frequency‐dependent dielectric permittivity maximum was found (Tm = 100 K at 5 kHz), which indicates relaxor behavior. Magnetic susceptibility measurements revealed purely paramagnetic behavior between 10 and 350 K. X‐ray diffraction measurements of Ba2LaFeNb4O15 single crystals revealed an incommensurate structure at room temperature with a bidimensional modulation characterized by vectors q1 = (α, α, 1/2) and q2 = (α, –α, 1/2) with α = 0.295(1). This crystal growth method offers a promising elaboration route to centimeter‐sized crystals of niobate‐based compounds, which may not be grown from the pure liquid phase, especially those with a tetragonal tungsten bronze (TTB) structure.
Synthesis, Molecular Structure, and Electrochemistry of 1‐Ferrocenyl‐1,2‐dicarba‐closo‐dodecaboranes
Authors: Korotvička Aleš , Šnajdr Ivan , Štěpnička Petr , Císařová Ivana , Janoušek Zbyněk , Kotora Martin
Published: April 2013

Bis(dimethylsulfido)decaborane, 6,9‐(Me2S)2‐arachno‐B10H12, reacts smoothly with ferrocenyl alkynes FcC≡CR [1a–h; Fc = ferrocenyl, R = H (1a), CH3 (1b), Ph (1c), 4‐MeO2CC6H4 (1d), Fc (1e), C≡CFc (1f), C(O)CH3 (1g), and CO2CH2CH3 (1h)] to afford the corresponding 1‐ferrocenyl‐1,2‐dicarba‐closo‐dodecaboranes 2a–h in good yields. Ester 2h was further reduced to the respective hydroxymethyl derivative, 1‐Fc‐2‐CH2OH‐1,2‐closo‐C2B10H10 (3). The reaction of 6,9‐(Me2S)2‐B10H12 with FcC≡CSiMe3 proceeded in a different manner to produce (among other products) an SMe2 adduct of an opened decaborane substituted with a 2‐ferrocenyl‐2‐(trimethylsilyl)ethen‐1‐yl group (4). This compound probably results through hydroboration of the starting alkyne and migration of the SiMe3 group. All prepared compounds were characterized by spectroscopic methods (1H, 13C, and 11B NMR spectroscopy, IR spectroscopy, and mass spectrometry), and their molecular structures were determined by single‐crystal X‐ray diffraction analysis. In addition, the compounds were studied by cyclic and differential pulse voltammetry on a platinum disc electrode to reveal simple ferrocenyl‐centered oxidations for the singly ferrocenylated carboranes and two consecutive oxidation waves for compounds 2e and 2f, which possess two ferrocenyl substituents.
Structural Diversity of Coordination Cores in Homoleptic Tetraaryltin(IV) Dioxolane, Aldehyde and Imines: The First Octacoordinated Double Helicate Tetraorganotin(IV) Compound
Authors: Barbul Ioana , Varga Richard A. , Silvestru Cristian
Published: April 2013

Reaction of [2‐{(CH2O)2CH}C6H4]Li with SnCl4 in a 4:1 molar ratio afforded [2‐{(CH2O)2CH}C6H4]4Sn (1), which was deprotected to give [2‐(O=CH)C6H4]4Sn (2). Homoleptic [2‐(RN=CH)C6H4]4Sn [R = Me2NCH2CH2 (3), 2,4,6‐Me3C6H2 (4), PhCH2 (5)] were obtained by condensation of 2 with the corresponding amine either in solution or by using a green, solvent‐free procedure for (imino)arylmetal species. All compounds were characterised by multinuclear NMR spectroscopy and mass spectrometry, and their molecular structures were determined by single‐crystal X‐ray diffraction. In all cases, the C4Sn core is distorted tetrahedral as a result of the combined effects of the intramolecular coordination of the heteroatoms from the organic ligands and the steric impediments imposed by the ligands. The overall coordination around tin was found to be different, that is, coordination numbers from six for 1 and 4, to seven for 3 and 5 and eight for 2. Compound 2 is the first example of a mononuclear tetraorganotin(IV) compound that contains an octacoordinated metal centre with a double helicate topology in the solid state. Multinuclear NMR spectroscopy studies in solutions of CDCl3 are consistent with equivalent organic groups attached to a tetracoordinate tin atom.
Iodine/Water‐Mediated Oxidation of o‐Alkynylaroyl Compounds and Application of the Products of Oxidation in the Synthesis of Nitrogen Heterocycles
Authors: Sakthivel Karuppusamy , Srinivasan Kannupal
Published: April 2013

A facile iodine/water‐mediated oxidation of the triple bond of o‐alkynylaroyl compounds to furnish tricarbonyl compounds is reported. The reaction proceeds through the formation of isochromenol intermediates by the assistance of the neighbouring aroyl group. The product tricarbonyl compounds are versatile synthetic precursors that, upon treatment with mono‐ and diamines, hydrazines and amino alcohols, afford various heterocyclic scaffolds such as isoindolinones, phthalazines, benzimidazoisoquinolinones, quinoxalines and benzimidazole‐quinoxaline hybrid compounds. Mechanistic aspects of the formation of the above heterocycles are discussed. Finally, a short synthetic route to the isoindolinone natural product, aristolactam BII is reported.
Epicoccolides: Antimicrobial and Antifungal Polyketides from an Endophytic Fungus Epicoccum sp. Associated with Theobroma cacao
Authors: Talontsi Ferdinand Mouafo , Dittrich Birger , Schüffler Anja , Sun Han , Laatsch Hartmut
Published: April 2013

In the search for new compounds to protect plants from fungi, an endophytic fungus, Epicoccum sp. CAFTBO, obtained from Theobroma cacao was found to produce three polyoxygenated polyketides, namely epicolactone (1) and epicoccolides A (2) and B (3), together with seven known metabolites. The structures of these compounds were elucidated by a combination of detailed spectroscopic and spectrometric analyses as well as DFT calculations of the electronic circular dichroism spectra and the single‐crystal X‐ray diffraction analysis of 1. Compounds 1–3 showed potent antimicrobial activities and significant inhibitory effects on the mycelial growth of two peronosporomycete phytopathogens, Pythium ultimum and Aphanomyces cochlioides, and the basidiomycetous fungus Rhizoctonia solani.
Hydrous magmatism triggered by assimilation of hydrothermally altered rocks in fossil oceanic crust (northern Oman ophiolite)
Authors: France Lydéric , Ildefonse Benoit , Koepke Juergen
Published: April 2013

Mid‐ocean ridges magmatism is, by and large, considered to be mostly dry. Nevertheless, numerous works in the last decade have shown that a hydrous component is likely to be involved in ocean ridges magmas genesis and/or evolution. The petrology and geochemistry of peculiar coarse grained gabbros sampled in the upper part of the gabbroic sequence from the northern Oman ophiolite (Wadi Rajmi) provide information on the origin and fate of hydrous melts in fast‐spreading oceanic settings. Uncommon crystallization sequences for oceanic settings (clinopyroxene crystallizing before plagioclase), extreme mineral compositions (plagioclase An% up to 99, and clinopyroxene Mg # up to 96), and the presence of magmatic amphibole, imply the presence of a high water activity during crystallization. Various petrological and geochemical constraints point to hydration, resulting from the recycling of hydrothermal fluids. This recycling event may have occurred at the top of the axial magma chamber where assimilation of anatectic hydrous melts is recurrent along mid‐ocean ridges or close to segments ends where fresh magma intrudes previously hydrothermally altered crust. In ophiolitic settings, hydration and remelting of hydrothermally altered rocks producing hydrous melts may also occur during the obduction process. Although dry magmatism dominates oceanic magmatism, the dynamic behavior of fast‐spreading ocean ridge magma chambers has the potential to produce the observed hydrous melts (either in ophiolites or at spreading centers), which are thus part of the general mid‐ocean ridges lineage.
Human cortical activity evoked by gaze shift observation: An intracranial EEG study
Authors: Caruana Fausto , Cantalupo Gaetano , Russo Giorgio Lo , Mai Roberto , Sartori Ivana , Avanzini Pietro
Published: April 2013

While is widely accepted that the posterior temporal region is activated during the observation of faces showing gaze shifts, it is still unclear whether its activity is stronger while observing direct or averted gaze. Furthermore, despite its assessed role in social cognition, studies describing an enhanced activity of the posterior temporal region during the observation of gaze aversion interpreted this activity in terms of spatial attention toward the target direction. This spatial attention interpretation is not easily reconcilable with the role of the posterior temporal region in social cognition, and an overarching view of its global cognitive function would be much more preferable. Here we used intracranial EEG to assess the precise spatial localization of the gaze shifts coding in the posterior temporal region, to assess its selectivity for direct versus averted gaze and to distinguish between a spatial‐attentional and a social interpretations of gaze aversion. We found stronger activation during gaze aversion than direct gaze and lateral side switch observation, the latter indicating that the crucial aspect of gaze aversion is the prior presence of the eye contact and its interruption, and not the gaze direction. These results suggest a more social‐oriented interpretation based on the view that among humans, gaze aversion signals a negative relational evaluation in social interaction. Hum Brain Mapp 35:1515–1528, 2014. © 2013 Wiley Periodicals, Inc.
Activation of the cerebellar cortex and the dentate nucleus in a prism adaptation fMRI study
Authors: Küper Michael , Wünnemann Meret J.S. , Thürling Markus , Stefanescu Roxana M. , Maderwald Stefan , Elles Hans G. , Göricke Sophia , Ladd Mark E. , Timmann Dagmar
Published: April 2013

During prism adaptation two types of learning processes can be distinguished. First, fast strategic motor control responses are predominant in the early course of prism adaptation to achieve rapid error correction within few trials. Second, slower spatial realignment occurs among the misaligned visual and proprioceptive sensorimotor coordinate system. The aim of the present ultra‐highfield (7T) functional magnetic resonance imaging (fMRI) study was to explore cerebellar cortical and dentate nucleus activation during the course of prism adaptation in relation to a similar visuomotor task without prism exposure. Nineteen young healthy participants were included into the study. Recently developed normalization procedures were applied for the cerebellar cortex and the dentate nucleus. By means of subtraction analysis (early prism adaptation > visuomotor, early prism adaptation > late prism adaptation) we identified ipsilateral activation associated with strategic motor control responses within the posterior cerebellar cortex (lobules VIII and IX) and the ventro‐caudal dentate nucleus. During the late phase of adaptation we observed pronounced activation of posterior parts of lobule VI, although subtraction analyses (late prism adaptation > visuomotor) remained negative. These results are in good accordance with the concept of a representation of non‐motor functions, here strategic control, within the ventro‐caudal dentate nucleus. Hum Brain Mapp 35:1574–1586, 2014. © 2013 Wiley‐Liss, Inc.
Shock‐like structures in the tropical cyclone boundary layer
Authors: Williams Gabriel J. , Taft Richard K. , McNoldy Brian D. , Schubert Wayne H.
Published: April 2013

This paper presents high horizontal resolution solutions of an axisymmetric, constant depth, slab boundary layer model designed to simulate the radial inflow and boundary layer pumping of a hurricane. Shock‐like structures of increasing intensity appear for category 1–5 hurricanes. For example, in the category 3 case, the
term in the radial equation of motion produces a shock‐like structure in the radial wind, i.e., near the radius of maximum tangential wind the boundary layer radial inflow decreases from approximately 22 m s−1 to zero over a radial distance of a few kilometers. Associated with this large convergence is a spike in the radial distribution of boundary layer pumping, with updrafts larger than 22 m s−1 at a height of 1000 m. Based on these model results, it is argued that observed hurricane updrafts of this magnitude so close to the ocean surface are attributable to the dry dynamics of the frictional boundary layer rather than moist convective dynamics. The shock‐like structure in the boundary layer radial wind also has important consequences for the evolution of the tangential wind and the vertical component of vorticity. On the inner side of the shock the tangential wind tendency is essentially zero, while on the outer side of the shock the tangential wind tendency is large due to the large radial inflow there. The result is the development of a U‐shaped tangential wind profile and the development of a thin region of large vorticity. In many respects, the model solutions resemble the remarkable structures observed in the boundary layer of Hurricane Hugo (1989).
Macrophages—Key cells in the response to wear debris from joint replacements
Authors: Nich Christophe , Takakubo Yuya , Pajarinen Jukka , Ainola Mari , Salem Abdelhakim , Sillat Tarvo , Rao Allison J. , Raska Milan , Tamaki Yasunobu , Takagi Michiaki , Konttinen Yrjö T. , Goodman Stuart B. , Gallo Jiri
Published: April 2013

The generation of wear debris is an inevitable result of normal usage of joint replacements. Wear debris particles stimulate local and systemic biological reactions resulting in chronic inflammation, periprosthetic bone destruction, and eventually, implant loosening, and revision surgery. The latter may be indicated in up to 15% patients in the decade following the arthroplasty using conventional polyethylene. Macrophages play multiple roles in both inflammation and in maintaining tissue homeostasis. As sentinels of the innate immune system, they are central to the initiation of this inflammatory cascade, characterized by the release of proinflammatory and pro‐osteoclastic factors. Similar to the response to pathogens, wear particles elicit a macrophage response, based on the unique properties of the cells belonging to this lineage, including sensing, chemotaxis, phagocytosis, and adaptive stimulation. The biological processes involved are complex, redundant, both local and systemic, and highly adaptive. Cells of the monocyte/macrophage lineage are implicated in this phenomenon, ultimately resulting in differentiation and activation of bone resorbing osteoclasts. Simultaneously, other distinct macrophage populations inhibit inflammation and protect the bone‐implant interface from osteolysis. Here, the current knowledge about the physiology of monocyte/macrophage lineage cells is reviewed. In addition, the pattern and consequences of their interaction with wear debris and the recent developments in this field are presented. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 3033–3045, 2013.
Rheological and mechanical properties of acellular and cell‐laden methacrylated gellan gum hydrogels
Authors: Silva‐Correia Joana , Gloria Antonio , Oliveira Mariana B. , Mano João F. , Oliveira Joaquim M. , Ambrosio Luigi , Reis Rui L.
Published: April 2013

Tissue engineered hydrogels hold great potential as nucleus pulposus substitutes (NP), as they promote intervertebral disc (IVD) regeneration and re‐establish its original function. But, the key to their success in future clinical applications greatly depends on its ability to replicate the native 3D micro‐environment and circumvent their limitation in terms of mechanical performance. In the present study, we investigated the rheological/mechanical properties of both ionic‐ (iGG‐MA) and photo‐crosslinked methacrylated gellan gum (phGG‐MA) hydrogels. Steady shear analysis, injectability and confined compression stress‐relaxation tests were carried out. The injectability of the reactive solutions employed for the preparation of iGG‐MA and phGG‐MA hydrogels was first studied, then the zero‐strain compressive modulus and permeability of the acellular hydrogels were evaluated. In addition, human intervertebral disc (hIVD) cells encapsulated in both iGG‐MA and phGG‐MA hydrogels were cultured in vitro, and its mechanical properties also investigated under dynamic mechanical analysis at 37°C and pH 7.4. After 21 days of culturing, hIVD cells were alive (Calcein AM) and the E′ of ionic‐crosslinked hydrogels and photo‐crosslinked was higher than that observed for acellular hydrogels. Our study suggests that methacrylated gellan gum hydrogels present promising mechanical and biological performance as hIVD cells were producing extracellular matrix. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 3438–3446, 2013.
Multiple gene polymorphisms can improve prediction of nonvertebral fracture in postmenopausal women
Authors: Lee Seung Hun , Lee Seon Woo , Ahn Seong Hee , Kim Taehyeung , Lim Kyeong-Hye , Kim Beom-Jun , Cho Eun-Hee , Kim Sang-Wook , Kim Tae-Ho , Kim Ghi Su , Kim Shin-Yoon , Koh Jung-Min , Kang Changwon
Published: April 2013

Clinical risk factors (CRFs), with or without bone mineral density (BMD), are used to determine the risk of osteoporotic fracture (OF), which has a heritable component. In this study we investigated whether genetic profiling can additionally improve the ability to predict OF. Using 1229 unrelated Korean postmenopausal women, 39 single-nucleotide polymorphisms (SNPs) in 30 human genomic loci were tested for association with osteoporosis-related traits, such as BMD, osteoporosis, vertebral fracture (VF), nonvertebral fracture (NVF), and any fracture. To estimate the effects of genetic profiling, the genetic risk score (GRS) was calculated using five prediction models: (Model I) GRSs only; (Model II) BMD only; (Model III) CRFs only; (Model IV) CRFs and BMD; and (Model V) CRFs, BMD, and GRS. A total of 21 SNPs within 19 genes associated with one or more osteoporosis-related traits and were included for GRS calculation. GRS associated with BMD before and after adjustment for CRFs (p ranging from <0.001 to 0.018). GRS associated with NVF before and after adjustment for CRFs and BMD (p ranging from 0.017 to 0.045), and with any fracture after adjustment for CRFs and femur neck BMD (p = 0.049). In terms of predicting NVF, the area under the receiver operating characteristic curve (AUC) for Model I was 0.55, which was lower than the AUCs of Models II (0.60), III (0.64), and IV (0.65). Adding GRS to Model IV (in Model V) increased the AUC to 0.67, and improved the accuracy of NVF classification by 11.5% (p = 0.014). In terms of predicting any fracture, the AUC of Model V (0.68) was similar to that of Model IV (0.68), and Model V did not significantly improve the accuracy of any fracture classification (p = 0.39). Thus, genetic profiling may enhance the accuracy of NVF predictions and help to delineate the intervention threshold. © 2013 American Society for Bone and Mineral Research.
Multiresidue LC–MS/MS analysis of cephalosporins and quinolones in milk following ultrasound‐assisted matrix solid‐phase dispersive extraction combined with the quick, easy, cheap, effective, rugged, and safe methodology
Authors: Karageorgou Eftichia , Myridakis Antonis , Stephanou Euripides G. , Samanidou Victoria
Published: April 2013

A sensitive and selective confirmatory method for milk‐residue analysis of ten quinolones and eight cephalosporins by LC‐MS/MS has been developed herein. For the chromatographic separation of target analytes, a Perfectsil ODS‐2 (250 × 4 mm, 5 μm) analytical column was used and gradient elution was applied, using a mobile phase of 0.1% w/w TFA in water and 0.1% w/w TFA in ACN. Ultrasound‐assisted matrix solid‐phase dispersion procedure was applied for the extraction and clean‐up procedure of antimicrobials agents from milk matrix using a mixture of Bond Elut Plexa sorbent and QuEChERS. The method was validated meeting the European Legislation determining selectivity, linearity response, trueness, precision (repeatability and between‐day reproducibility), decision limit, detection capability, and ruggedness following the Youden approach. Recoveries of all antibiotics ranged from 81.7 to 117.9%, while RSD values were lower than 13.7%. Limits of quantification for all examined compounds ranged from 2.4 to 15.0 μg/kg, substantially lower than the maximum residue limits established by the European Union (30–100 μg/kg).
Fat – carbohydrate – protein: Storage in plant seeds
Authors: Lüttge Ulrich
Published: April 2013

Storage compounds of seeds are carbohydrates, proteins and oils or fats. They are inter‐convertible in metabolism. Most seeds store the whole complement of these compound classes though one or the other may dominate. The storage compounds supply material and energy to young growing seedlings and are of commercial interest of man for food and fuel.
Predicting pKa Values in Aqueous Solution for the Guanidine Functional Group from Gas Phase Ab Initio Bond Lengths
Authors: Griffiths Mark Z. , Alkorta Ibon , Popelier Paul L. A.
Published: April 2013

Here we applied a novel method1a to predict pKa values of the guanidine functional group, which is a notoriously difficult. This method, which was developed in our lab, uses only one ab initio bond length obtained at a low level of theory. The method is shown to work for drug molecules, delivers prediction errors of less than 0.5 log units, successfully treats tautomerisation in close relation with experiment, and demonstrates strong correlations with only a few data points. The high structural content of the ab initio bond length makes a given data set essentially divide itself into high correlation subsets. One then observes that molecules within a subset possess a common substructure. Each high correlation subset exists in its own region of chemical space. The high correlation subset method is explored with respect to this position in chemical space, in particular tautomerisation. The proposed method is able to distinguish between different tautomeric forms and the preferred tautomeric form emerges naturally, in agreement with experiment.
Imaging in childhood cancer: A society for pediatric radiology and children's oncology group joint task force report
Authors: Weiser Daniel A. , Kaste Sue C. , Siegel Marilyn J. , Adamson Peter C.
Published: April 2013

Contemporary medical imaging is a cornerstone of care for children with cancer. As 5‐year survival rates for children with cancer exceed 80%, imaging technologies have evolved in parallel to include a wide array of modalities. Here, we overview the risks and benefits associated with commonly used imaging modalities and survey the current landscape of medical imaging for children with cancer. We find evidence‐based imaging guidelines to assist in protocol development and to guide decision‐making for optimal patient care are often lacking. The substantial variation in protocol‐based recommendations for imaging both during and following therapy may hinder optimal clinical research and clinical care for children with cancer. Pediatr Blood Cancer 2013;601253‐1260. © 2013 Wiley Periodicals, Inc.
Effects of Fe2+ ions on morphologies, microstructures and mechanical properties of electrospun nylon‐6 nanofibers
Authors: Kimura Naotaka , Kim Byoung‐Suhk , Kim Ick‐Soo
Published: April 2013

In this study, nylon‐6 nanofiber mats containing Fe2+ ions were fabricated via electrospinning. The resultant electrospun nylon‐6/FeCl2 nanofiber mats were characterized by SEM, TEM, Fourier transform IR spectroscopy, wide angle XRD and DSC. Unique morphological features, such as spider's‐web‐like morphologies, were observed and became evident with increasing additive Fe2+ ions. The metastable γ form was predominant in the as‐spun nylon‐6 nanofibers. The relative intensity of such γ form gradually decreased with increasing additive Fe2+ ions, indicative of transformation of the crystalline structure in the electrospun nylon‐6/FeCl2 nanofibers due to strong molecular interactions between the nylon‐6 backbone and the additive Fe2+ ions. The effects of additive Fe2+ ions on the mechanical properties of both nonwoven nanofiber mats and single nanofibers were investigated. In particular, Young's modulus of nylon‐6/FeCl2 single nanofibers gradually increased from 1.46 to 5.26 GPa with increasing additive Fe2+ ions. © 2013 Society of Chemical Industry
TiO2 Nanotube Array/Monolayer Graphene Film Schottky Junction Ultraviolet Light Photodetectors
Authors: Wang Ming‐Zheng , Liang Feng‐Xia , Nie Biao , Zeng Long‐Hui , Zheng Ling‐Xia , Lv Peng , Yu Yong‐Qiang , Xie Chao , Li Yang Yang , Luo Lin‐Bao
Published: April 2013

Schottky junctions made from a titanium dioxide nanotube (TiO2NT) array in contact with a monolayer graphene (MLG) film are fabricated and utilized for UV light detection. The TiO2NT array is synthesized by the anodization and the MLG through a simple chemical vapor deposition process. Photoconductive analysis shows that the fabricated Schottky junction photodetector (PD) is sensitive to UV light illumination with good stability and reproducibility. The corresponding responsivity (R), photoconductive gain (G), and detectivity (D*) are calculated to be 15 A W−1, 51, and 1.5 × 1012 cm Hz1/2 W−1, respectively. It is observed that the fabricated PD exhibits spectral sensitivity and a simple power‐law dependence on light intensity. Moreover, the height of the Schottky junction diode is derived to be 0.59 V by using a low temperature I–V measurement. Finally, the working mechanism of the TiO2NT array/MLG film Schottky junction PD is elucidated.
Colloidosomes as Single Implantable Beads for the In Vivo Delivery of Hydrophobic Drugs
Authors: Porta Fabiola , Kros Alexander
Published: April 2013

The synthesis of silica‐based colloidosomes with a polymer core obtained via inverse Pickering emulsification and their use as an implantable drug delivery system in zebrafish are described. Silica nanoparticles act as a stabilizer of a water‐in‐oil emulsion creating aqueous droplets with a silica shell. The core of the colloidosomes is polymerized resulting in tough particles. Colloidosomes loaded with model drugs show a release profile dependent on the porosity of the silica nanoparticles. Studying the effect of drugs on zebrafish development and tail regeneration is a new and emerging field in biomedical research. The in vivo delivery and bioactivity of retinoic acid from single implanted colloidosomes in partially amputated caudal fins are shown at the phenotype and genotype level. The colloidosomes are biocompatible since no signs of inflammation are observed. With these initial studies, the use of colloidosomes as single implantable beads is demonstrated for the local in vivo release of bioactive drugs. It is envisioned that these single particles can be applied for a broad range of hydrophobic drugs.
Structure of the RNA‐directed RNA Polymerase from the cystovirus ϕ12
Authors: Ren Zhen , Franklin Matthew C. , Ghose Ranajeet
Published: April 2013

We have determined the structure of P2, the self‐priming RdRp from cystovirus ϕ12 in two crystal forms (A, B) at resolutions of 1.7 Å and 2.1 Å. Form A contains Mg2+ bound at a site that deviates from the canonical noncatalytic position seen in form B. These structures provide insight into the temperature sensitivity of a ts‐mutant. However, the tunnel through which template ssRNA accesses the active site is partially occluded by a flexible loop; this feature, along with suboptimal positioning of other structural elements that prevent the formation of a stable initiation complex, indicate an inactive conformation in crystallo. Proteins 2013; 81:1479–1484. © 2013 Wiley Periodicals, Inc.
Fabrication and characteristics of solution‐processed graphene oxide–silicon heterojunction
Authors: Kalita Golap , Wakita Koichi , Umeno Masayoshi , Tanemura Masaki
Published: April 2013

We demonstrate the fabrication of a solid state heterojunction photovoltaic device with solution‐processed graphene oxide (GO) and n‐Si. Partially reduced GO with a high optical gap (2.8 eV) was spin‐coated on the n‐Si substrate and a heterojunction device was fabricated with the structure of Au/pr‐GO/n‐Si. In the fabricated device, incident light was transmitted through the thin GO film to reach the junction interface, generating photoexciton, and thereby a photovoltaic action was observed. By means of a built‐in electric potential at the GO/n‐Si junction, photoexcited electrons and holes can be separated, transported and collected at the electrodes.

magnified image

Solid state heterojunction device fabricated with solution‐processed graphene oxide (high optical gap ∼2.8 eV) and n‐Si.

(© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Recyclable Polymer‐Supported Nanometal Catalysts in Water
Authors: Ohtaka Atsushi
Published: April 2013

Two types of polymer‐supported nanometal catalysts with high catalytic activity and recyclability in water have been developed. One catalyst was composed of linear polystyrene‐stabilized metal nanoparticles (PS‐MtNPs). A palladium catalyst (PS‐PdONPs) was prepared in water by the thermal decomposition of Pd(OAc)2 in the presence of polystyrene. The degree of immobilization of Pd, but not the size of the Pd nanoparticles, was dependent on the molecular weight and cross‐linking of the polystyrene. The PS‐PdONPs exhibited high catalytic activity for Suzuki, Heck, and Sonogashira coupling reactions in water and they could be recycled without loss of activity. Linear polystyrene was also suitable as a stabilizer for in situ generated PdNPs and PtNPs. The second catalyst was a polyion complex that was composed of poly[4‐chloromethylstyrene‐co‐(4‐vinylbenzyl)tributylammonium chloride] and poly(acrylic acid)‐stabilized PdNPs (PIC‐PdNPs). Aggregation and redispersion of PIC‐PdNPs were easily controlled by adjusting the pH value of the solution.
Copper Solution Chemistry of Cyclic Pseudo‐Octapeptides
Authors: Comba Peter , Dovalil Nina , Haberhauer Gebhard , Kowski Klaus , Mehrkens Nina , Westphal Michael
Published: April 2013

The CuII solution chemistry of synthetic derivatives of naturally occurring pseudo‐octapeptides (patellamides and ascidiacyclamide) is described. The complex stabilities [mono‐ and dicopper(II) complexes] of five different ligands were determined by isothermal microcalorimetry (ITC), and square wave voltammetry (SQW) was used to elucidate the electrochemical properties. In agreement with published spectroscopic data, there is cooperative binding of two CuII ions and the overall stabilities are, in agreement with known stabilities of the natural ligands and expectations based on the donor sets (two N‐based heterocycles and one amide per CuII), only moderate (K ≤ 106). There is a slight dependence of the stabilities on the ligand structure (configuration of the side chains), and that derived from the natural products forms the most stable complexes. Due to the complex equilibria in solution and the instability of the reduced forms, voltammetry shows complex equilibria, which preclude the full assignment of all processes. The positive reduction potentials are in agreement with relatively low complex stabilities. These observations complete earlier studies, concentrating on spectroscopy and structural aspects, and are also discussed in relation to the possible biological function of the cyclic peptides, i.e. metal ion transport, oxygen activation, carboanhydrase, and phosphatase activities.
Dissection of Different Donor Abilities Within Bis(pyrazolyl)­pyridinylmethane Transition Metal Complexes
Authors: Hoffmann Alexander , Herres‐Pawlis Sonja
Published: April 2013

Using the bis(pyrazolyl)pyridinylmethane ligand α,α,α‐bis(1‐pyrazolyl)(2‐pyridinyl)toluene {(ph)C(pz)2(py)} for bioinorganic inspired coordination chemistry studies, we synthesised and structurally characterised three monofacial complexes [{(ph)C(pz)2(py)}CoCl2] (C1), [{(ph)C(pz)2(py)}CuCl2] (C2), [{(ph)C(pz)2(py)}ZnCl2] (C3) and the binuclear halogenido‐bridged complexes [{(ph)C(pz)2(py)}2(μ‐Cl)2Fe2Cl2] (C4) and [{(ph)C(pz)2(py)}2(μ‐Br)2Cu2Br2] (C5). In four of these complexes, severe disorders between pyrazolyl and pyridinyl donor groups are observed such that bis(pyrazolyl) and (pyrazolyl)(pyridinyl) coordination modes are concomitantly found. The donor competition is dissected by DFT calculation of the energy differences between the two coordination modes and NBO analysis of the donor situation. The pyrazolyl units provide with more donor strength although pyridine is considerably more basic.
A Distinct Tetradentate N2O2‐type Ligand: (o‐Carboranyl)bis(2‐hydroxymethyl)pyridine
Authors: Di Salvo Florencia , Teixidor Francesc , Viñas Clara , Giner Planas José
Published: April 2013

A new chiral racemic ligand (o‐carboranyl)bis(2‐hydroxymethyl)pyridine oCB(hmpH)2, that is composed of a central o‐carborane unit where two arms radiate out of the cluster carbons each one containing a 2‐pyridylmethylalcohol chelating arms, provides two potentially bidentate {NO} or one tetradentate {N2O2} binding pockets. An unprecedented octahedral CoII complex [CoCl2(anti‐oCB(hmpH)2] was obtained under aerobic conditions and characterized by X‐ray crystallography as well as IR and NMR spectroscopy. anti‐oCB(hmpH)2 acts as a tetradentate N2O2‐ligand affording the complex as a racemic mixture of cis‐α Δ‐[CoCl2(RRanti‐oCB(hmpH)2)] and Λ‐[CoCl2(SSanti‐oCB(hmpH)2)]. The new ligand oCB(hmpH)2 appears to be suitable for producing a variety of new chiral‐at‐metal complexes.
Quantum critical lines in holographic phases with (un)broken symmetry
Authors: Goutéraux B. , Kiritsis E.
Published: April 2013

Abstract

All possible scaling IR asymptotics in homogeneous, translation invariant holographic phases preserving or breaking a U(1) symmetry in the IR are classified. Scale invariant geometries where the scalar extremizes its effective potential are distinguished from hyperscaling violating geometries where the scalar runs logarithmically. It is shown that the general critical saddle-point solutions are characterized by three critical exponents (θ, z, ζ). Both exact solutions as well as leading behaviors are exhibited. Using them, neutral or charged geometries realizing both fractionalized or cohesive phases are found. The generic global IR picture emerging is that of quantum critical lines, separated by quantum critical points which correspond to the scale invariant solutions with a constant scalar.
Enhanced supersymmetry from vanishing Euler number
Authors: Kashani-Poor Amir-Kian , Minasian Ruben , Triendl Hagen
Published: April 2013

Abstract

We argue that compactifications on Calabi-Yau threefolds with vanishing Euler number yield effective four dimensional theories exhibiting (spontaneously broken) N = 4 supersymmetry. To this end, we derive the low-energy effective action for general SU(2) structure manifolds in type IIA string theory and show its consistency with gauged N = 4 supergravity. Focusing on the special case of Calabi-Yau manifolds with vanishing Euler number, we explain the absence of perturbative corrections at the two-derivative level. In addition, we conjecture that all non-perturbative corrections are governed and constrained by the couplings of N = 4 massive gravitino multiplets.
Linolenic Acid as the Main Source of Acrolein Formed During Heating of Vegetable Oils
Authors: Endo Yasushi , Hayashi Chieko , Yamanaka Takashi , Takayose Koichi , Yamaoka Miki , Tsuno Takuo , Nakajima Shigeo
Published: April 2013

Acrolein, which is an irritating and off‐flavor compound formed during heating of vegetable oils, was estimated by the gas–liquid chromatography (GLC). Several vegetable oils such as high‐oleic sunflower, perilla, rapeseed, rice bran, and soybean oils were heated at 180 °C for 480 min and then the concentration of acrolein in the head space gas was determined by GLC. The formation of acrolein was greatest in perilla oil among the tested oils, while it was much lower in rice bran oil and high‐oleic sunflower oil. There was a good correlation between the level of acrolein and linolenate (18:3n‐3) in the vegetable oils. To investigate the formation of acrolein from linolenate, methyl oleate, methyl linoleate, and methyl linolenate were also heated at 180 °C, and the amounts of acrolein formed from them were determined by GLC. The level of acrolein was the greatest in methyl linolenate. Acrolein was also formed from methyl linoleate, but not from methyl oleate. Acrolein in vegetable oils may be formed from polyunsaturated fatty acids, especially linolenic acid but not from glycerol backbone in triacylglycerols.
A Statistical Appraisal to Hydrogeochemistry of Fluoride Contaminated Ground Water in Nayagarh District, Odisha
Authors: Routroy S. , Harichandan R. , Mohanty J. K. , Panda C.R.
Published: April 2013

Seasonal variation of ground water in Nayagarh district, Odisha is determined by analysing both pre and post monsoon water samples. The high fluoride content is an endemic problem in the area and special attention was attached to the point. The chemical compositions of the ground water of the area are dominated by CaCl, NaCl and mixed CaMgCl types in pre-monsoon and CaHCO3-mixed CaMgCl type in post-monsoon. This is largely due to chemical weathering of Eastern Ghats Mobile Belt rock types. Increasing alkalinity vis-a-vis F concentration in pre-monsoon is associated with sodium-bicarbonate water types having high pH (>7) and low calcium and magnesium contents. The percentage of total high fluoride containing water samples is nearly double in pre-monsoon than in post-monsoon. During both the seasons, pH values indicate mildly alkaline to weakly acidic nature of the water samples. Fluoride concentration has good correlation with pH in pre-monsoon whereas in post-monsoon it shows good correlation with Fe. Facies analysis indicates that water is becoming predominantly Ca-Na cation and Cl-SO4-HCO3 anion type in pre-monsoon than Ca-Mg type and HCO3- Cl-SO4 type in post-monsoon. The seasonal variations in concentrations of anthropogenic components demonstrate that the groundwater system is very less liable to pollution by human activities.
Antileukemic potential of PEGylated gold nanoparticle conjugated with protein toxin (NKCT1) isolated from Indian cobra (Naja kaouthia) venom
Authors: Bhowmik Tanmoy , Saha Partha Pratim , Dasgupta Anjan , Gomes Antony
Published: April 2013

Limited efficacy of current first-line treatment for leukemia calls attention for further development of efficient strategies. Recently, much attention has been given to nanoparticle-based drug delivery systems loaded with dual drugs to improve current disease therapies by overcoming toxicity. In the present study, we document to explore an approach to conjugate gold nanoparticles (GNPs) with protein toxin (NKCT1), a protein toxin from the Indian cobra (Naja kaouthia) venom, and to establish its antileukemic activity. GNP was prepared by NaBH4 reduction method. UV–vis spectroscopy of GNP showed the absorbance at 530 nm for plasma resonance. Dynamic light scattering (DLS) size of GNPs was 2–8 nm and the GNP-NKCT1 was 68–122 nm. CD spectra of GNP-NKCT1 showed change in percentage of β-turn as compared with NKCT1. GNP-NKCT1 significantly inhibited leukemic cell growth in dose- and time-dependent manner by two- to threefold more than NKCT1. For human leukemic lymphoma cell line and human myelogenous leukemic cell line, the IC50 dose was found to be 1.2 and 0.75 μg/ml, respectively, observed by trypan blue exclusion method and tetrazolium bromide reduction assay. Flow cytometric analysis showed appreciable number of both cell lines in early and late apoptotic stages and arrested cell cycle in the G1 phase by GNP-NKCT1. Resilient power of leukemic cell line after wound healing and migration or invasive power of the cell line was significantly low in GNP-NKCT1-treated plate than the control plate. These analyses reveal that GNP-NKCT1 possesses significant and selective anticancer activity, likely by inducing programmed cell death through mitochondrial and/or lysosomal pathway.
Rectification: Best abstracts of the NVMO conference
Authors: Michels Nele
Published: April 2013

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Problem of early elections and dissolution power in the Czech Republic
Authors: Brunclik Milos
Published: April 2013

Theory of parliamentary regimes presumes that parliament can express vote of no confidence in government. On the other hand executive power (government or head of state) is endowed with right to dissolve the parliament. However, these “doomsday devices” are not in balance in many parliamentary regimes, including the Czech Republic. On the basis of a comparative analysis of dissolution provisions in the constitutions of European states the article argues that the government in the Czech Republic should be given the right to dissolve the lower chamber at least in case that the latter expresses vote of no confidence in the former.
CITIZENSHIP OF THE EUROPEAN UNION
Authors: Cygan Adam
Published: April 2013

The relationship between EU law and international law has, again, recently occupied the European Court of Justice with respect to the compatibility of the EU Treaty with international obligations. It will be recalled that in the Kadi judgment1 the Court examined whether adoption of a UN Resolution in the form of a Council Regulation2 which, prima facie, restricted the fundamental rights of Kadi was congruent with principles of EU law. In Kadi, the Court, adopting a constitutionalist position with regard to the protection of fundamental rights, held that protecting the applicant's fundamental rights under the Treaty was a priority which could not be diminished, even when the EU was implementing a UN Resolution into EU law. Thus, in Kadi, the Court concluded that providing clear fundamental rights safeguards through judicial review of the Regulation was a fundamental principle of EU law. To this extent, the Court was only prepared to accept compliance with internal obligations if they were harmonious with principles of fundamental rights norms, as understood through the case law of the Court.
EXPANDING AKZO NOBEL: IN-HOUSE COUNSEL, GOVERNMENT LAWYERS, AND INDEPENDENCE
Authors: Stefanelli Justine N
Published: April 2013

Following on from its judgment in Akzo Nobel,1 the Court of Justice of the European Union (CJEU) on 6 September 2012 delivered its judgment in Prezes.2Prezes expanded the decision in Akzo Nobel, which held that communications between a client and its in-house legal counsel were not protected by legal privilege because the latter are not considered sufficiently independent from the former. Taking this holding one step further, the CJEU in Prezes held not only that corporations are unable to benefit from legal privilege regarding communications with their in-house counsel, but also that any lawyer in an employment relationship with its client is disqualified from representing their client before the CJEU. This article criticizes this holding and argues that the CJEU's interpretation of independence does two things: (1) unreasonably expands the scope of Akzo Nobel to include the representation of in-house counsel in all cases; and (2) does so in a way which is inconsistent in light of similar concerns of the independence of government lawyers, who seemingly maintain their right of privilege under the judgment.
The Politics of Sour Grapes: Sartre, Elster, and Tocqueville on Frustration, Failure, and Self-Deception
Authors: McLendon Michael Locke
Published: April 2013

Jean-Paul Sartre and Jon Elster have taken great interest in the famous “children's” fable, “The Fox and the Grapes.” Elster believes the fable pinpoints problems in utilitarian doctrine while Sartre contends it demonstrates how consciousness copes with frustrated desire. As impressive as these insights are, neither philosopher can fully explain the cognitive and cultural processes involved in sour grapes. To improve upon their theories, I will argue thatamour-propreis an important psychological motive inspiring sour grapes as well as show that sour grapes is built into the value commitments and institutional structures of democratic life through Tocqueville's analysis of American democracy.