bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Unanticipated Dimerization of Ce@C2v(9)‐C82 upon Co‐crystallization with Ni(octaethylporphyrin) and Comparison with Monomeric M@C2v(9)‐C82 (M = La, Sc, and Y)
Authors: Suzuki Mitsuaki , Yamada Michio , Maeda Yutaka , Sato Satoru , Takano Yuta , Uhlík Filip , Slanina Zdenek , Lian Yongfu , Lu Xing , Nagase Shigeru , Olmstead Marilyn M. , Balch Alan L. , Akasaka Takeshi 
Published: October 2016

AbstractWe report that Ce@C2v(9)‐C82 forms a centrosymmetric dimer when co‐crystallized with Ni(OEP) (OEP = octaethylporphyrin dianion). The crystal structure of {Ce@C2v(9)‐C82}2⋅2[Ni(OEP)]⋅4 C6H6 shows that a new C−C bond with a bond length of 1.605(5) Å connects the two cages. The high spin density of the singly occupied molecular orbital (SOMO) on the cage and the pyramidalization of the cage are factors that favor dimerization. In contrast, the treatment of Ni(OEP) with M@C2v(9)‐C82 (M = La, Sc, and Y) results in crystallization of monomeric endohedral fullerenes. A systematic comparison of the X‐ray structures of M@C2v(9)‐C82 (M = Sc, Y, La, Ce, Gd, Yb, and Sm) reveals that the major metal site in each case is located at an off‐center position adjacent to a hexagonal ring along the C2 axis of the C2v(9)‐C82 cage. DFT calculations at the M06‐2X level revealed that the positions of the metal centers in these metallofullerenes M@C2v(9)‐C82 (M = Sc, Y, and Ce), as determined by single‐crystal X‐ray structure studies, correspond to an energy minimum for each compound.
A Phosphorescent Platinum(II) Bipyridyl Supramolecular Polymer Based on Quadruple Hydrogen Bonds
Authors: Liu Fang‐Wei , Niu Li‐Ya , Chen Yong , Ramamurthy Vaidhyanathan , Wu Li‐Zhu , Tung Chen‐Ho , Chen Yu‐Zhe , Yang Qing‐Zheng 
Published: October 2016

AbstractA platinum(II) bipyridyl complex bearing bis‐ureidopyrimidinone (Pt‐bisUPy) has been designed and its self‐assembling behavior has been thoroughly investigated by 1H NMR, DOSY NMR, Ubbelohde viscometry analysis, UV/Vis, and emission spectroscopies. Pt‐bisUPy underwent concentration‐dependent ring‐chain polymerization in apolar solvents. Hydrogen‐bonding interactions play an important role during the formation of the supramolecular polymers. Hydrogen‐bonded supramolecular polymers were transformed to nanoparticles in water through the miniemulsion method. These nanoparticles showed strong π–π excimeric emission. Metal‐metal‐to‐ligand charge transfer (MMLCT) from Pt–Pt interactions was not significant in the emission spectrum. The phosphorescence of the nanoparticle persisted even under aerobic conditions. The triplet state of these phosphorescent nanomaterials were long‐lived and possessed moderate emission quantum yields. Furthermore, the low toxicity of these materials promises a place for them in in vitro and in vivo bioimaging.
Enantiopure Sulfinyl Aniline as a Removable and Recyclable Chiral Auxiliary for Asymmetric C(sp3)−H Bond Activation
Authors: Jerhaoui Soufyan , Chahdoura Faouzi , Rose Clémence , Djukic Jean‐Pierre , Wencel‐Delord Joanna , Colobert Françoise 
Published: October 2016

AbstractAn original and recyclable chiral bidentate aniline‐sulfoxide‐based directing group has been developed. This auxiliary allows challenging stereoselective Pd‐catalyzed direct functionalization of small cycloalkanes through C–aryl and C–alkyl bond formation. Although moderate diastereoselectivities are observed, both optically pure enantiomers of the highly functionalized products can be obtained separately by simple silica gel chromatography and cleavage of the chiral auxiliary. This strategy was further applied to the preparation of enantiomerically pure 1,2,3‐trisubstituted cyclopropane carboxylic acid derivatives, with three stereogenic centers and bearing both alkyl and aromatic substituents. These molecular scaffolds are not yet reported in the literature. The synthetic utility of this approach is validated by the chiral auxiliary being readily cleaved and recovered posteriori to the C−H activation step, without deterioration of its optical purity. Finally, an unprecedented palladacycle intermediate generated through C−H activation of the cyclopropane moiety has been isolated and fully characterized. Initial DFT calculations shed additional light on the reactivity of this original intermediate.
Effect of Atomic‐Scale Differences on the Self‐Assembly of Thiophene‐based Polycatenars in Liquid Crystalline and Organogel States
Authors: Pradhan Balaram , Vaisakh V. M. , Nair Geetha G. , Rao D. S. Shankar , Prasad S. Krishna , Sudhakar Achalkumar Ammathnadu 
Published: October 2016

AbstractTwo series of polycatenars are reported that contain a central thiophene moiety connected to two substituted oxadiazole or thiadiazole units. The number, position, and length of the peripheral chains connected to these molecules were varied. The oxadiazole‐based polycatenars exhibited columnar phases with rectangular and hexagonal or oblique symmetry, whereas the thiadiazole‐based polycatenars exhibited columnar phases with rectangular and/or hexagonal symmetry. All of the compounds exhibited bright emission in the solution and thin‐film states. Two oxadiazole‐based molecules and one thiadiazole‐based molecule exhibited supergelation ability in hydrocarbon solvents, which is mainly supported by attractive π–π interactions. These gels showed aggregation‐induced enhanced emission, which is of high technological importance for applications in solid‐state emissive displays. X‐ray diffraction studies of the xerogel fibers of oxadiazole‐based polycatenars revealed a columnar rectangular organization, whereas a hexagonal columnar arrangement was observed for thiadiazole‐based polycatenars. Rheological measurements carried out on the samples quantitatively confirmed the formation of gels and showed that these gels are mechanically robust. The impact of an atomic‐scale difference (oxygen to sulfur, <2 % of the molecular weight) on the self‐assembly and the macroscopic properties of those self‐assembled structures are clearly visualized.
Electrochemical Synthesis of Amorphous VO2 Colloids and Their Rapid Thermal Transforming to VO2(M) Nanoparticles with Good Thermochromic Performance
Authors: Wu Hao , Li Ming , Zhong Li , Luo Yuan Yuan , Li Guang Hai 
Published: October 2016

AbstractAmorphous VO2 (a‐VO2) colloids were synthesized by electrochemical anodic oxidation of metallic vanadium. It was found that the a‐VO2 colloids have a cotton‐like morphology composed of very small clusters, and that the crystallization temperature of the a‐VO2 colloids can be adjusted either by the electrolyte of the anodic oxidation or/and the dispersion agent of the colloids. VO2(M) nanoparticles (NPs) (and a NP film) with an average size of about 50 nm can be obtained by a rapid thermal annealing of the a‐VO2 colloids at 310 °C under air, which is beneficial for practical applications. The VO2(M) NP film shows an obvious metal–semiconductor transition with a resistance less than 10 Ω in the metallic state. An integral visible transmittance of 40.7 %, a solar transmittance modulation of 9.4 %, and a resistance modulation in the order of 5×104 were realized in the VO2(M) NP film.
Strongly Coupled Oxasmaragdyrin–BF2 Chelated Dipyrrin Dyads: Syntheses, X‐ray Structure, Ground‐ and Excited‐State Charge‐Transfer Interactions
Authors: Gobeze Habtom B. , Kumar Sunit , D'Souza Francis , Ravikanth Mangalampalli 
Published: October 2016

AbstractOxasmaragdyrin (osm), a 22‐π electron aromatic macrocycle containing four pyrroles and a furan ring connected by three methine bridges and two direct bonds is shown to be an excellent electron donor–sensitizer exhibiting adequate spectral and redox properties. Further, this novel heterocyclic macromolecule has been utilized in building donor–acceptor systems involving BF2‐chelated dipyrromethenes (BODIPYs). The osm–BODIPY dyads were fully characterized by optical, electrochemical, computational, and X‐ray diffraction studies. Due to close proximity and electronic structure of the donor and acceptor entities, strong intramolecular charge‐transfer interactions in these dyads was witnessed and was supported by computational studies. Solvent‐polarity‐dependent rapid charge separation and charge recombination in these dyads is witnessed from photochemical studies involving time‐resolved emission and femtosecond transient absorption studies. The present studies bring out the importance of oxasmaragdyrin as an electron donor in light‐energy‐harvesting artificial photosynthesis model systems.
Analysis of flumequine enantiomers in rat plasma by UFLC‐ESI‐MS/MS
Authors: Hu Zhao–Hong , Wang Yang–Guang , Jin Huo–Xi , Ouyang Xiao–Kun , Wu Wei–Jian 
Published: October 2016

AbstractIn this study the analysis and confirmation of flumequine enantiomers in rat plasma by ultra‐fast liquid chromatography coupled with electron spray ionization mass spectrometry (using propranolol as an internal standard [IS]) was developed and validated. Plasma samples were prepared by liquid–liquid extraction using methyl tert‐butyl ether as the extraction solvent. Direct resolution of the R‐ and S‐isomers was performed on a CHIRALCEL OJ‐RH column (4.6 × 150 mm, 5 μm) using acetonitrile / 0.1% formic acid / 1 mM ammonium acetate as the mobile phase. Detection was operated by electron spray ionization in the selected ion monitoring and positive ion mode. The target ions at m/z 262.1 and m/z 260.1 were selected for the quantification of the enantiomers and IS, respectively. The linear range was 0.5–500 ng/mL. The precisions (coefficient of variation, CV%) and recoveries were 1.43–8.68 and 94.24–106.76%, respectively. The lowest quantitation limit for both enantiomers is 0.5 ng/mL, which is sensitive enough to be applied to sample analysis in other related studies.
Linear modeling of modern artist paints using a modification of the opaque form of Kubelka‐Munk turbid media theory
Authors: Moghareh Abed Farhad , Berns Roy S. 
Published: October 2016

AbstractA new model of turbid medium theory is proposed that combines the best parts of the opaque forms of Kubelka‐Munk single and two constant models. This model introduces an impurity index, a spectrally nonselective scattering coefficient for each chromatic component. The new model is shown to have a convex, linear dependence on colorant concentration so that it can be used for colorant identification in high‐resolution images of works of art while offering an extension to the single constant model that can predict the absorption and scattering of paints, both in mixture and pure (masstone) forms. The model was tested and validated using 28 matte acrylic dispersion paints, of the type used in modern painting. These paints had a wide range of absorption and scattering characteristics. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 308–315, 2017
Photoexcited Triplet State Kinetics Studied by Electron Paramagnetic Resonance Spectroscopy
Authors: Hintze Christian , Steiner Ulrich E. , Drescher Malte 
Published: October 2016

AbstractFollowing the first evidence of the triplet character of the optically excited phosphorescent state of naphthalene by Hutchison and Mangum in 1958, electron paramagnetic resonance (EPR) spectroscopy has become widely used to study and understand the properties and kinetic characteristics of excited triplet states. This minireview gives an overview over EPR techniques based on continuous microwave methods using lock‐in or direct detection as well as pulsed EPR methods with respect to their suitability for kinetic studies of excited triplet states. A short historical overview of the experimental and theoretical developments in this field of research as well as of the triplet systems studied, with a final focus on fullerenes, is given. This may help newcomers to the field as a guide to the relevant literature.
Supramolecular Organogelation of Bacteriochlorophyll‐c Possessing an Isobutyl Substituent at the 8‐Position in Carbon Tetrachloride
Authors: Mizoguchi Tadashi , Kinoshita Yusuke , Harada Jiro , Tamiaki Hitoshi 
Published: October 2016

AbstractThe supramolecular organogelation of bacteriochlorophyll(BChl)‐c carrying an isobutyl substituent at the 8‐position was observed in carbon tetrachloride at a concentration of about 10 mm at room temperature. The BChl‐c gel was evaluated by several spectroscopic measurements: the electronic absorption spectrum exhibited a far‐red shift of the Qy‐absorption from 660 to 748 nm and the FTIR spectrum showed a shorter frequency shift of the 13‐C=O stretching from 1683 to 1643 cm−1 compared to the shifts of the corresponding monomer solution in tetrahydrofuran. These observations strongly indicate that the gelating BChl‐c molecules form self‐aggregates that are reminiscent of light‐harvesting chlorosomes of green photosynthetic bacteria. The present supramolecular organogel prepared from natural chlorophylls is promising for the creation of an intelligent soft material involving artificial photosynthesis.
Competitive Adsorption of Substrate and Solvent in Sn‐Beta Zeolite During Sugar Isomerization
Authors: van der Graaff William N. P. , Tempelman Christiaan H. L. , Li Guanna , Mezari Brahim , Kosinov Nikolay , Pidko Evgeny A. , Hensen Emiel J. M. 
Published: October 2016

AbstractThe isomerization of 1,3‐dihydroxyactone and d‐glucose over Sn‐Beta zeolite was investigated by in situ 13C NMR spectroscopy. The conversion rate at room temperature is higher when the zeolite is dehydrated before exposure to the aqueous sugar solution. Mass transfer limitations in the zeolite micropores were excluded by comparing Sn‐Beta samples with different crystal sizes. Periodic density functional theory (DFT) calculations show that sugar and water molecules compete for adsorption on the active framework Sn centers. Careful solvent selection may thus increase the rate of sugar isomerization. Consistent with this prediction, batch catalytic experiments show that the use of a co‐solvent, such as tetrahydrofuran, that strongly interacts with the Sn centers suppresses glucose isomerization. On the other hand, the use of ethanol as cosolvent results in significantly higher isomerization activity in comparison with pure water because of decreased competition with glucose adsorption on zeolitic Sn sites.
Near‐Infrared‐Absorbing and Dopant‐Free Heterocyclic Quinoid‐Based Hole‐Transporting Materials for Efficient Perovskite Solar Cells
Authors: Ni Jen‐Shyang , Hsieh Hsiao‐Chi , Chen Chun‐An , Wen Yuh‐Sheng , Wu Wen‐Ti , Shih Yen‐Chen , Lin King‐Fu , Wang Leeyih , Lin Jiann T. 
Published: October 2016

AbstractNew heterocyclic quinoid‐based hole transporting materials (HTMs) with a rigid quinoid core [3,6‐di(2H‐imidazol‐2‐ylidene)cyclohexa‐1,4‐diene] have been synthesized. The new HTMs have good hole mobility (>10−4 cm2 V−1 s−1) and very intense absorption in the near‐infrared region extending to >800 nm. High performance perovskite solar cells can be fabricated using these HTMs without dopant. The best cell efficiency under simulated AM 1.5 G illumination reaches 12.22 %, which is comparable with that (12.58 %) using doped 2,2′,7,7′‐tetrakis‐(N,N‐di‐4‐methoxyphenylamino)‐9,9′‐spirobifluorene (spiro‐OMeTAD) as the HTM.
Molecularly Defined Manganese Pincer Complexes for Selective Transfer Hydrogenation of Ketones
Authors: Perez Marc , Elangovan Saravanakumar , Spannenberg Anke , Junge Kathrin , Beller Matthias 
Published: October 2016

AbstractFor the first time an easily accessible and well‐defined manganese N,N,N‐pincer complex catalyzes the transfer hydrogenation of a broad range of ketones with good to excellent yields. This cheap earth abundant‐metal based catalyst provides access to useful secondary alcohols without the need of hydrogen gas. Preliminary investigations to explore the mechanism of this transformation are also reported.
Efficient Ionic‐Liquid‐Promoted Chemical Fixation of CO2 into α‐Alkylidene Cyclic Carbonates
Authors: Qiu Jikuan , Zhao Yuling , Li Zhiyong , Wang Huiyong , Fan Maohong , Wang Jianji 
Published: October 2016

AbstractThe efficient conversion of CO2 into value‐added chemicals under metal‐free conditions is of significant importance from the viewpoint of sustainable chemistry. In this work, ionic liquids (ILs) with different properties were used to promote the reaction between CO2 and propargylic alcohol for the synthesis of α‐alkylidene cyclic carbonates. The protic IL 1,8‐diazabicyclo‐[5.4.0]‐7‐undecenium 2‐methylimidazolide ([DBUH][MIm]) was prepared by simple neutralization of the superbase with a weak proton donor and could efficiently promote the reactions in high yields. After the reactions, the IL was separated from the reaction mixtures by simply adding water, and then reused after drying without an observable decrease in the catalytic activity and selectivity. NMR spectroscopy and detailed density functional theory analysis were used to propose a reaction mechanism. Both the cation and anion of the IL played a key synergistic role in promoting the reaction. These findings may be useful for the rational design of novel metal‐free and recyclable routes for the reaction between CO2 and propargylic alcohols.
Effect of liraglutide, a glucagon‐like peptide‐1 analogue, on left ventricular function in stable chronic heart failure patients with and without diabetes (LIVE)—a multicentre, double‐blind, randomised, placebo‐controlled trial
Authors: Jorsal Anders , Kistorp Caroline , Holmager Pernille , Tougaard Rasmus Stilling , Nielsen Roni , Hänselmann Anja , Nilsson Brian , Møller Jacob Eifer , Hjort Jakob , Rasmussen Jon , Boesgaard Trine Welløv , Schou Morten , Videbæk Lars , Gustafsson Ida , Flyvbjerg Allan , Wiggers Henrik , Tarnow Lise 
Published: October 2016

AimsTo determine the effect of the glucagon‐like peptide‐1 analogue liraglutide on left ventricular function in chronic heart failure patients with and without type 2 diabetes.Methods and resultsLIVE was an investigator‐initiated, randomised, double‐blinded, placebo‐controlled multicentre trial. Patients (n = 241) with reduced left ventricular ejection fraction (LVEF ≤45%) were recruited (February 2012 to August 2015). Patients were clinically stable and on optimal heart failure treatment. Intervention was liraglutide 1.8 mg once daily or matching placebo for 24 weeks. The LVEF was similar at baseline in the liraglutide and the placebo group (33.7 ± 7.6% vs. 35.4 ± 9.4%). Change in LVEF did not differ between the liraglutide and the placebo group; mean difference (95% confidence interval) was −0.8% (−2.1, 0.5; P = 0.24). Heart rate increased with liraglutide [mean difference: 7 b.p.m. (5, 9), P < 0.0001]. Serious cardiac events were seen in 12 (10%) patients treated with liraglutide compared with 3 (3%) patients in the placebo group (P = 0.04).ConclusionLiraglutide did not affect left ventricular systolic function compared with placebo in stable chronic heart failure patients with and without diabetes. Treatment with liraglutide was associated with an increase in heart rate and more serious cardiac adverse events, and this raises some concern with respect to the use of liraglutide in patients with chronic heart failure and reduced left ventricular function. More data on the safety of liraglutide in different subgroups of heart failure patients are needed.
Optimal control for reinitialization in finite element level set methods
Authors: Basting Christopher , Kuzmin Dmitri , Shadid John N. 
Published: October 2016

SummaryA new optimal control problem that incorporates the residual of the Eikonal equation into its objective is presented. The formulation of the state equation is based on the level set transport equation but extended by an additional source term, correcting the solution so as to minimize the objective functional. The method enforces the constraint so that the interface cannot be displaced at least in the continuous setting. The system of first‐order optimality conditions is derived, linearized, and solved numerically. The control also prevents numerical instabilities, so that no additional stabilization techniques are required. This approach offers the flexibility to include other desired design criteria into the objective functional. The methodology is evaluated numerically in three different examples and compared with other PDE‐based reinitialization techniques. Copyright © 2016 John Wiley & Sons, Ltd.
Tonotopic maps in human auditory cortex using arterial spin labeling
Authors: Gardumi Anna , Ivanov Dimo , Havlicek Martin , Formisano Elia , Uludağ Kâmil 
Published: October 2016

AbstractA tonotopic organization of the human auditory cortex (AC) has been reliably found by neuroimaging studies. However, a full characterization and parcellation of the AC is still lacking. In this study, we employed pseudo‐continuous arterial spin labeling (pCASL) to map tonotopy and voice selective regions using, for the first time, cerebral blood flow (CBF). We demonstrated the feasibility of CBF‐based tonotopy and found a good agreement with BOLD signal‐based tonotopy, despite the lower contrast‐to‐noise ratio of CBF. Quantitative perfusion mapping of baseline CBF showed a region of high perfusion centered on Heschl's gyrus and corresponding to the main high‐low‐high frequency gradients, co‐located to the presumed primary auditory core and suggesting baseline CBF as a novel marker for AC parcellation. Furthermore, susceptibility weighted imaging was employed to investigate the tissue specificity of CBF and BOLD signal and the possible venous bias of BOLD‐based tonotopy. For BOLD only active voxels, we found a higher percentage of vein contamination than for CBF only active voxels. Taken together, we demonstrated that both baseline and stimulus‐induced CBF is an alternative fMRI approach to the standard BOLD signal to study auditory processing and delineate the functional organization of the auditory cortex. Hum Brain Mapp 38:1140–1154, 2017. © 2016 Wiley Periodicals, Inc.
Impact of lymphocytic thyroiditis on incidence of pathological incidental thyroid carcinoma
Authors: Farrell Eric , Heffron Cynthia , Murphy Matthew , O'Leary Gerard , Sheahan Patrick 
Published: October 2016

AbstractBackgroundThe purpose of this study was to investigate the impact of lymphocytic thyroiditis on incidence of incidental thyroid cancers.MethodsWe conducted a retrospective review of 713 consecutive patients who underwent thyroidectomies. Incidental thyroid cancer was defined as an unexpected cancer discovered on pathological examination outside the index nodule undergoing preoperative cytology.ResultsWe excluded 65 cases because of preoperative diagnosis of thyroid cancer, and 68 because of nonincidental cancer within the index nodule. Among the remaining 580 cases, there were 43 cases (7.4%) of incidental thyroid cancers. Incidental thyroid cancers were significantly associated with moderate/severe lymphocytic thyroiditis (relative risk = 2.5; p = .03). Sixteen of 56 patients with moderate/severe lymphocytic thyroiditis had Graves' disease, none of whom had incidental thyroid cancer. The risk of incidental thyroid cancer associated with moderate/severe lymphocytic thyroiditis was significantly higher in non‐Graves' than patients with Graves' disease (p = .05).ConclusionThe risk of incidental thyroid cancer is significantly increased in patients with moderate/severe lymphocytic thyroiditis. Moderate/severe lymphocytic thyroiditis associated with Graves' disease seems to have a lower risk of incidental thyroid cancer. © 2016 Wiley Periodicals, Inc. Head Neck 39: 122–127, 2017