bluuebunny/crossref_metadata_2025_split huggingface dataset:
Single‐Crystal‐to‐Single‐Crystal Transformation and Solvochromic Luminescence of a Dinuclear Gold(I)–(Aza‐[18]crown‐6)dithiocarbamate Compound
Authors: Tzeng Biing‐Chiau , Chao An 
Published: December 2014

AbstractThe treatment of [AuCl(SMe2)] with an equimolar amount of NaO5NCS2 (O5NCS2=(aza‐[18]crown‐6)dithiocarbamate) in CH3CN gave [Au2(O5NCS2)2]⋅2 CH3CN (2⋅2 CH3CN), and its crystal structure displays a dinuclear gold(I)‐azacrown ether ring and an intermolecular gold(I)⋅⋅⋅gold(I) contact of 2.8355(3) Å in crystal lattices. It is noted that two other single crystals of 2⋅tert‐butylbenzene⋅H2O and 2⋅0.5 m‐xylene can be successfully obtained from a single‐crystal‐to‐single‐crystal (SCSC) transformation process by immersing single crystals of 2⋅2 CH3CN in the respective solvents, and both also show intermolecular gold(I)⋅⋅⋅gold(I) contacts of 2.9420(5) and 2.890(2)–2.902(2) Å, respectively. Significantly, the emissions of all three 2⋅solvates are well correlated with their respective intermolecular gold(I)⋅⋅⋅gold(I) contacts, where such contacts increase with 2⋅2 CH3CN (2.8355(3) Å)<2⋅0.5 m‐xylene (2.890(2)–2.902(2) Å)<2⋅tert‐butylbenzene⋅H2O (2.9420(5) Å), and their emission energies increase with 2⋅2 CH3CN (602 nm)<2⋅0.5 m‐xylene (583 nm)<2⋅tert‐butylbenzene⋅H2O (546 nm) as well. In this regard, we further examine the solvochromic luminescence for some other aromatics, and finally their emissions are within 546–602 nm. Obviously, the above results are mostly ascribed to the occurrence of intermolecular gold(I)⋅⋅⋅gold(I) contacts in 2⋅solvates, which are induced by the presence of various solvates in the solid state, as a key role to be responsible for their solvochromic luminescence.
Ln3Q9 as a Molecular Framework for Ion‐Size‐Driven Assembly of Heterolanthanide (Nd, Er, Yb) Multiple Near‐Infrared Emitters
Authors: Artizzu Flavia , Quochi Francesco , Marchiò Luciano , Correia Raquel Fonseca , Saba Michele , Serpe Angela , Mura Andrea , Mercuri Maria Laura , Bongiovanni Giovanni , Deplano Paola 
Published: December 2014

AbstractA unique example of discrete molecular entity NdyErxYb3−(x+y)Q9 (1) (Q=quinolinolato) containing three different lanthanides simultaneously emitting in three different spectral regions in the NIR, ranging from 900 to 1600 nm, has been synthesized and fully chararacterized. A simple molecular strategy based on tuning metal composition in the Ln3Q9 framework, which contains inequivalent central and terminal coordination sites, has allowed a satisfactory ion‐size‐driven control of molecular speciation close to 90 %. In 1 the central position of the larger Nd ion is well distinguished from the terminal ones of the smaller Yb3+ and Er3+, which are almost “vicariants” as found in the heterobimetallic ErxYb3−xQ9 (2). The Ln3Q9 molecular architecture, which allows communication between the ions, has proved to afford multiple NIR emission in 1 and 2, and is promising to develop a variety of multifunctional materials through the variation of the Ln composition.
Synthesis of Bridged Benzazocines and Benzoxocines by a Titanium‐Catalyzed Double‐Reductive Umpolung Strategy
Authors: Bichovski Plamen , Haas Thomas M. , Kratzert Daniel , Streuff Jan 
Published: December 2014

AbstractA sequence of two titanium(III)‐catalyzed reductive umpolung reactions is reported that allows the rapid construction of benzazo‐ and benzoxozine building blocks. The first step is a reductive cross‐coupling of quinolones or chromones with Michael acceptors. This reaction proceeds with complete syn‐selectivity for the quinolone functionalization while the anti‐diastereomers are obtained as the major products from chromones. With different reaction conditions, the stereochemical outcome can be altered to afford the syn‐chromanone products as well. A subsequent reductive ketyl radical cyclization forges the tricyclic title compounds in good yields. A stereochemical model explaining the observed stereoselectivities is provided and the product configurations were unambiguously verified by X‐ray analyses and 2D NMR spectroscopic experiments.
Regiodivergent Cyclobutanone Cleavage: Switching Selectivity with Different Lewis Acids
Authors: Souillart Laetitia , Cramer Nicolai 
Published: December 2014

AbstractThe exploitation of strain release in small rings as driving force to enable complex transformations is a powerful synthetic tool. Among them, cyclobutanones are particularly versatile substrates that can be elaborated in a wide variety of structurally diverse building blocks. Herein, Lewis acid catalyzed rearrangement reactions are presented that provide selective access to two structurally distinct polycyclic scaffolds, that is, indenylacetic acid derivatives and benzoxabicyclo[3.2.1]octan‐3‐ones. The choice of the Lewis acid fully controls the reaction pathway and the regioselectivity of the cyclobutanone CC bond cleavage site.
Gas Phase Structures of Peroxides: Experiments and Computational Problems
Authors: Oberhammer Heinz 
Published: December 2014

AbstractGas‐phase structures of several organic and inorganic peroxides X‐O‐O‐X and X‐O‐O‐X′, which have been determined experimentally by gas electron diffraction and/or microwave spectroscopy, are discussed. The OO bond length in these peroxides varies from 1.481(8) Å in Me3SiOOSiMe3 to 1.214(2) Å in FOOF and the dihedral angle ϕ(XO‐OX) between 0° in HC(O)O‐OH and near 180° in ButO‐OBut. Some of the peroxides cause problems for quantum chemistry, since several computational methods fail to reproduce the experimental structures. Extreme examples are MeO‐OMe and FO‐OF. In the case of MeO‐OMe only about half of the more than 100 computational methods reported in the literature reproduce the experimentally determined double‐minimum shape of the torsional potential around the OO bond correctly. For FO‐OF only a small number of close to 200 computational methods reproduce the OO and OF bond lengths better than ±0.02 Å.
A Nanostructured PLGA System for Cell Delivery of a Tetrathiahelicene as a Model for Helical DNA Intercalators
Authors: Cauteruccio Silvia , Bartoli Cristina , Carrara Claudio , Dova Davide , Errico Cesare , Ciampi Giulia , Dinucci Dinuccio , Licandro Emanuela , Chiellini Federica 
Published: December 2014

AbstractA novel nanoconstruct based on poly(lactic‐co‐glycolic acid) nanoparticles loaded with a tetrathiahelicene molecule conjugated to a fluorescent rhodamine probe was prepared and characterized. Because helicenes are known to be very promising DNA intercalators, the tetrathiahelicene was selected for this study as a model therapeutic cytotoxic molecule. The ability of the nanoconstruct to internalize the tetrathiahelicene and deliver it intracellularly in a safe manner has been investigated by means of cytotoxicity and cell uptake tests on Balb/3T3 clone A31 fibroblasts. The outcomes of this study suggest the suitability of the developed nanoconstruct to act as a vector for the intracellular delivery of hydrophobic small molecules, such as helicenes, thus contributing to their possible future exploitation as novel therapeutics.
Carbazolo[2,1‐a]carbazole Diimide: A Building Block for Organic Electronic Materials
Authors: Zhao Zheng , Wang Zhongli , Zhang Xu , Gao Simin , Yang Xiaodi , Duan Zhiming , Gao Xike 
Published: December 2014

AbstractA new class of carbazolo[2,1‐a]carbazole diimide compounds (CBZCBZ‐DI, 3) are designed and synthesized. The synthesis, X‐ray crystal structure, absorption spectra, and electrochemical properties of 3 as well as the charge transport properties are investigated. Theoretical calculation is also carried out based on the X‐ray crystal structure of 3 a to understand the relationship between the structure and the charge transport properties. Single‐crystal X‐ray analysis revealed that the molecules of 3 a adopt a slipped face‐to‐face π‐stacking mode with a large intermolecular π‐overlap and an interplanar distance of 3.4 Å. Crystalline transistors of 3 a display high hole mobility of 0.5 cm2 V−1 s−1, which is among the highest reported mobility values for carbazole‐based N‐heteroacenes. Two useful brominated derivatives (4, 5) are also prepared for synthesizing more new π‐functional materials.
Rhenium‐Catalyzed Deoxydehydration of Diols and Polyols
Authors: Dethlefsen Johannes R. , Fristrup Peter 
Published: December 2014

AbstractThe substitution of platform chemicals of fossil origin by biomass‐derived analogues requires the development of chemical transformations capable of reducing the very high oxygen content of biomass. One such reaction, which has received increasing attention within the past five years, is the rhenium‐catalyzed deoxydehydration (DODH) of a vicinal diol into an alkene; this is a model system for abundant polyols like glycerol and sugar alcohols. The present contribution includes a review of early investigations of stoichiometric reactions involving rhenium, diols, and alkenes followed by a discussion of the various catalytic systems that have been developed with emphasis on the nature of the reductant, the substrate scope, and mechanistic investigations.
Functionalized Fe3O4@Silica Core–Shell Nanoparticles as Microalgae Harvester and Catalyst for Biodiesel Production
Authors: Chiang Ya‐Dong , Dutta Saikat , Chen Ching‐Tien , Huang Yu‐Tzu , Lin Kuen‐Song , Wu Jeffrey C. S. , Suzuki Norihiro , Yamauchi Yusuke , Wu Kevin C.‐W. 
Published: December 2014

AbstractCore–shell Fe3O4@silica magnetic nanoparticles functionalized with a strong base, triazabicyclodecene (TBD), were successfully synthesized for harvesting microalgae and for one‐pot microalgae‐to‐fatty acid methyl ester (FAME, or so‐called biodiesel) conversion. Three types of algae oil sources (i.e., dried algae, algae oil, and algae concentrate) were used and the reaction conditions were optimized to achieve the maximum biodiesel yield. The results obtained in this study show that our TBD‐functionalized Fe3O4@silica nanoparticles could effectively convert algae oil to biodiesel with a maximum yield of 97.1 %. Additionally, TBD‐Fe3O4@silica nanoparticles act as an efficient algae harvester because of their adsorption and magnetic properties. The method presented in this study demonstrates the wide scope for the use of covalently functionalized core–shell nanoparticles for the production of liquid transportation fuels from algal biomass.
Biomass measurement by flow cytometry during solid‐state fermentation of basidiomycetes
Authors: Steudler Susanne , Böhmer Ulrike , Weber Jost , Bley Thomas 
Published: December 2014

AbstractSolid‐state fermentation (SSF) is a robust process that is well suited to the on‐site cultivation of basidiomycetes that produce enzymes for the treatment of lignocellulosics. Reliable methods for biomass quantification are essential for the analysis of fungal growth kinetics. However, direct biomass determination is not possible during SSF because the fungi grow into the substrate and use it as a nutrient source. This necessitates the use of indirect methods that are either very laborious and time consuming or can only provide biomass measurements during certain growth periods. Here, we describe the development and optimization of a new rapid method for fungal biomass determination during SSF that is based on counting fungal nuclei by flow cytometry. Fungal biomass was grown on an organic substrate and its concentration was measured by isolating the nuclei from the fungal hyphae after cell disruption, staining them with SYTOX® Green, and then counting them using a flow cytometer. A calibration curve relating the dry biomass of the samples to their concentrations of nuclei was established. Multiple buffers and disruption methods were tested. The results obtained were compared with values determined using the method of ergosterol determination, a classical technique for fungal biomass measurement during SSF. Our new approach can be used to measure fungal biomass on a range of different scales, from 15 mL cultures to a laboratory reactor with a working volume of 10 L (developed by the Research Center for Medical Technology and Biotechnology (fzmb GmbH)). © 2014 International Society for Advancement of Cytometry
Predicting fine‐scale distributions of peripheral aquatic species in headwater streams
Authors: DeRolph Christopher R. , Nelson Stacy A. C. , Kwak Thomas J. , Hain Ernie F. 
Published: December 2014

AbstractHeadwater species and peripheral populations that occupy habitat at the edge of a species range may hold an increased conservation value to managers due to their potential to maximize intraspecies diversity and species' adaptive capabilities in the context of rapid environmental change. The southern Appalachian Mountains are the southern extent of the geographic range of nativeSalvelinus fontinalisand naturalizedOncorhynchus mykissandSalmo truttain eastern North America. We predicted distributions of these peripheral, headwater wild trout populations at a fine scale to serve as a planning and management tool for resource managers to maximize resistance and resilience of these populations in the face of anthropogenic stressors. We developed correlative logistic regression models to predict occurrence of brook trout, rainbow trout, and brown trout for every interconfluence stream reach in the study area. A stream network was generated to capture a more consistent representation of headwater streams. Each of the final models had four significant metrics in common: stream order, fragmentation, precipitation, and land cover. Strahler stream order was found to be the most influential variable in two of the three final models and the second most influential variable in the other model. Greater than 70% presence accuracy was achieved for all three models. The underrepresentation of headwater streams in commonly used hydrography datasets is an important consideration that warrants close examination when forecasting headwater species distributions and range estimates. Additionally, it appears that a relative watershed position metric (e.g., stream order) is an important surrogate variable (even when elevation is included) for biotic interactions across the landscape in areas where headwater species distributions are influenced by topographical gradients.
Use of a Bioelectronic Tongue for the Monitoring of the Photodegradation of Phenolic Compounds
Authors: Cetó Xavier , González‐Calabuig Andreu , del Valle Manel 
Published: December 2014

AbstractThe application of a voltammetric bioelectronic tongue for the simultaneous monitoring of catechol, m‐cresol and guaiacol in wastewater is reported. Voltammetric responses obtained from an array of bulk modified (bio)sensors, containing enzymes such as tyrosinase and laccase, were combined with chemometric tools such as artificial neural networks (ANNs) for building the quantitative prediction model. To this end, the chemometric model was first built employing a factorial design, validated employing an external test set of samples (n=14; total NRMSE of 0.076), and afterwards applied to the monitoring of the mineralization of the three phenol pollutants during a photo‐Fenton advanced oxidation process.
A New Amperometric Benzaldhyde Biosensor Based on Aldehyde Oxidase Immobilized on Fe3O4‐GrapheneOxide/Polyvinylpyrrolidone/Polyaniline Nanocomposite
Authors: Sadeghi Susan , Fooladi Ebrahim , Malekaneh Mohammad 
Published: December 2014

AbstractA new biosensor for determination of benzaldehyde based on carbon past electrode (CPE) modified with a Fe3O4‐graphen oxide/polyvinyl pyrrolidone/polyaniline (Fe3O4/GO/PVP/PANI) nanocomposite was developed. The nanocomposite was electrodeposited on the surface of CPE using cyclic voltammetry technique. The crude extract aldehyde (AOX) oxidase enzyme isolated from rat liver was immobilized on the Fe3O4/GO/PVP/PANI nanocomposite and the prepared biosensor was employed for benzaldehyde oxidation to H2O2. The benzaldhyde measured amperometrically based on reduction of produced H2O2 at −0.25 V(vs. Ag/AgCl). The cyclic voltammetry and electrochemical impedance spectroscopy studies of the modified electrode indicated that Fe3O4/GO has an excellent electrocatalytic activity and can be used as an electron mediator for H2O2 reduction. The presence of PVP in the nanocomposite could substantially improve the dispersibility of GO, leading to enhanced sensitivity of the biosensor. Under optimum conditions, the biosensor exhibited a fast response time to benzaldhyde within 10 s. The sensor showed a linear response to benzaldehyde concentration in the range of 0.5–50 µM with a limit of detection of 0.4 µM(S/N=3) and sensitivity of 4.173 µA µM−1 cm−2. The biosensor revealed a preference for benzldehyde than studied aliphatic aldehydes. The new biosensor showed good performance to analysis of benzaldhyde in drugs injection formulations.
Macroporous Bismuth Film Screen‐Printed Carbon Electrode for Simultaneous Determination of Ni(II) and Co(II)
Authors: Dal Borgo Sebastiano , Sopha Hanna , Smarzewska Sylwia , Hočevar Samo B. , Švancara Ivan , Metelka Radovan 
Published: December 2014

AbstractMacroporous bismuth film screen‐printed carbon electrode (mpBiF‐SPCE) was used for simultaneous measurement of Ni(II) and Co(II) at their trace concentration level by means of adsorptive cathodic stripping voltammetry with dimethylglyoxime as a complexing agent. The mpBiF‐SPCE was prepared on a screen printed carbon electrode by colloidal crystal templating using aqueous suspension of polystyrene microspheres which were self‐assembled onto the electrode by slow evaporation of solvent. Following the electrochemical deposition of bismuth film, the microspheres were dissolved with toluene providing the macroporous bismuth film structure. The mpBiF‐SPCE offered good electroanalytical performance with estimated limits of detection of 27 and 94 ng L−1 for Ni(II) and Co(II), respectively, in combination with an accumulation time of 180 s, and relative standard deviations of 3.3 % for Ni(II) and 5.2 % for Co(II). The effect of potentially interfering ions and the surface‐active compounds was also investigated. Both Ni(II) and Co(II) were assayed in the sample of sewer water with satisfactory recovery.
Carbon‐Supported Cu‐Doped Mn–Co Spinel‐Type Oxides Used as Cathodic Catalysts for the Oxygen Reduction Reaction in Dual‐Chambered Microbial Fuel Cells
Authors: Hu Dengping , Wang Haijun , Wang Juan , Zhong Qin 
Published: December 2014

AbstractIn this study, carbon‐black‐supported Cu‐doped Mn–Co spinel‐type oxides (MnxCu1−xCo2O4/C, x=0, 0.2, 0.4, 0.6, 1) were synthesized by using a hydrothermal method. Firstly, the morphology characterization shows that the as‐prepared MnxCu1−xCo2O4 nanoparticles with the crystalline spinel structure are uniformly dispersed on the carbon black and the MnxCu1−xCo2O4/C samples possess high specific surface area. The neutral oxygen reduction reaction (ORR) performance of MnxCu1−xCo2O4/C evaluated by cyclic voltammetry (CV) shows that all catalysts can catalyze the ORR. Mn0.6Cu0.4Co2O4/C exhibited the highest catalytic activity, which might be due to its highest surface area. Finally, the MnxCu1−xCo2O4/C samples were used for microbial fuel cells (MFCs) as cathodic catalysts. The polarization curves demonstrate that Mn0.6Cu0.4Co2O4/C owns the best power output, close to 20 wt % Pt/C. This study suggests that using Mn0.6Cu0.4Co2O4/C instead of Pt/C could potentially improve the feasibility of scaling up MFCs for real applications by lowering the production cost.
The hemostatic system as a regulator of inflammation in atherosclerosis
Authors: Koch Miriam , Zernecke Alma 
Published: December 2014

AbstractAtherosclerosis is a chronic inflammatory disease of the arterial vessel wall. As part of a tightly connected cross‐talk between inflammation and coagulation, there is growing evidence that the coagulation system plays a pivotal role in the development and progression of atherosclerosis. We here discuss the presence of coagulation factors in atherosclerotic lesions and the overall effects of hypercoagulability and hypocoagulability on atherosclerotic lesion formation. Moreover, we focus on the unifying common pathway of coagulation, which can be initiated by the intrinsic and extrinsic pathway of coagulation, and discuss the functions of the coagulation factors FX, thrombin, and FXIII as regulators of inflammation in atherosclerosis. In particular, we review the non‐hemostatic and immune‐modulatory functions of these factors in endothelial and smooth muscle cells, as well as monocytes/macrophages, but also other cells, such as dendritic cells and T cells, that may control the inflammatory process of atherosclerosis. Their multiple roles in coagulation, but also their non‐hemostatic functions in different cell types in inflammation and immunity, may harbor great potential for the development of novel therapeutic approaches for treating cardiovascular disease. © 2014 IUBMB Life, 66(11):735–744, 2014
Prognostic significance of VEGF‐C, semaphorin 3F, and neuropilin‐2 expression in oral squamous cell carcinomas and their relationship with lymphangiogenesis
Authors: Zhang Bing , Gao Zhongxiuzi , Sun Miao , Li Haixia , Fan Haixia , Chen Dong , Zheng Jinhua 
Published: December 2014

BackgroundNeuropilin‐2 (NRP2), a receptor for vascular endothelial growth factor C (VEGF‐C) and semaphorin 3 F (SEMA3F), is a possible regulator of tumor progression and angiogenesis. However, little evidence of a correlation between NRP2 expression and lymphangiogenesis has been reported. SEMA3F might suppress lymphangiogenesis by competing with VEGF‐C for binding to NRP2.MethodsWe evaluated lymphatic vessel density (LVD), lymphatic vessel invasion (LVI), the expression levels of VEGF‐C, SEMA3F, and NRP2 by immunohistochemistry in 80 cases of oral squamous cell carcinomas (OSCCs).ResultsIn these tumors, the expression of NRP2 was positively associated with T stage classification, lymph node metastasis, LVD, LVI, and the expression of VEGF‐C. In contrast, low expression of SEMA3F was significantly related to poor differentiation and higher incidence of lymph node metastasis. Patients expressing high levels of VEGF‐C or NRP2, or low levels of SEMA3F had a higher risk of recurrence and shorter overall survival. Multivariate analysis showed that VEGF‐C and NRP2 were independent prognostic markers for overall survival.ConclusionsResults indicate SEMA3F is an inhibitor of tumor progression and provide evidence for an association between NRP2 and VEGF‐C, lymphangiogenesis, lymph node metastasis. This suggests the prognostic significance and potential therapeutic value of the VEGF‐C/SEMA3F/NRP2 axis for OSCCs.J. Surg. Oncol. 2015 111:382–388. © 2014 Wiley Periodicals, Inc.
Predicting Blast Waves from the Axial Direction of a Cylindrical Charge
Authors: Knock Clare , Davies Nigel , Reeves Thomas 
Published: December 2014

AbstractBare, cylindrical, explosive charges produce secondary shock waves in the direction of least presented area. Whilst the source of these shock waves was explored in the 1940’s, no attempt was made to predict them. This paper describes the detonation of bare, cylindrical charges of PE4 (RDX binder 88/12 %), mass 0.2 to 0.46 kg and with a length to diameter ratio of 4 to 1. High speed camera footage showed (i) the formation of the separate, primary, shock waves from the sides and ends of the charge, (ii) Mach reflection of these separate shock waves, giving rise to reflected, secondary shock waves, and (iii) the secondary shock waves catching and merging with the primary shock wave. In the axial direction, the secondary shock wave’s peak overpressure and impulse exceeded that of the primary shock wave for scaled distances, Z=R/M1/3≥3.9 m kg−1/3, whereMis the mass in kg andRthe distance from the charge in m. It was found possible to predict the primary peak overpressure,P, at all distances in the axial direction, for a constant length to diameter ratio, usingP=3075 Z−3−1732 Z−2+305 Z−1. Close in the primary peak overpressure is proportional toM/R3in the axial direction. It was not possible to predict the secondary peak overpressure with the data obtained. The total impulse from both shock waves,I, in the axial direction can be predicted usingI=746(M2/3/R)3−708(M2/3/R)2+306(M2/3/R).