bluuebunny/crossref_metadata_2025_split huggingface dataset:
Silver Triflate‐Palladium Chloride Cooperative Catalysis in a Tandem Reaction for the Synthesis of H‐Pyrazolo[5,1‐a]isoquinolines
Authors: Xiao Qing , Sheng Jie , Ding Qiuping , Wu Jie 
Published: August 2013

AbstractA tandem reaction of N′‐(2‐alkynylbenzylidene)hydrazone with alcohol in the presence of oxygen co‐catalyzed by silver triflate and palladium chloride under mild conditions is reported, providing H‐pyrazolo[5,1‐a]isoquinolines in good yields. During the transformation, isoquinolinium‐2‐yl amide was the key intermediate via a silver(I)‐catalyzed 6‐endo cyclization of N′‐(2‐alkynylbenzylidene)hydrazone. The presence of a palladium catalyst and molecular oxygen promoted the oxidation of the alcohol to the aldehyde or ketone. Subsequent nucleophilic attack of the in situ generated enolate to isoquinolinium‐2‐yl amide, intramolecular condensation, and aromatization afforded the H‐pyrazolo[5,1‐a]isoquinolines. The easily available starting materials, good substrate generality, mild reaction conditions, and experimental ease should make this method attractive for further library construction.magnified image
Synthesis and Structures of Air‐Stable Binuclear Hafnocene Perfluorobutanesulfonate and Perfluorobenzenesulfonate and their Catalytic Application in CC Bond‐Forming Reactions
Authors: Li Ningbo , Zhang Xiaohong , Xu Xinhua , Chen Yun , Qiu Renhua , Chen Jinyang , Wang Xie , Yin Shuang‐Feng 
Published: August 2013

AbstractThe two air‐stable μ2‐hydroxy‐bridged binuclear hafnocene perfluorobutanesulfonate and perfluorobenzenesulfonate complexes were successfully synthesized. The high catalytic activity and recyclability of these complexes were exemplified for various carbon‐carbon bond formation reactions. Compared with our previously reported hafnocene perfluorooctanesulfonate, these complexes show stronger Lewis acidity and better catalytic activity, and should find broad applications in organic synthesis.magnified image
Carbene Transfer – A New Pathway for Propargylic Esters in Gold Catalysis
Authors: Lauterbach Tobias , Gatzweiler Sabrina , Nösel Pascal , Rudolph Matthias , Rominger Frank , Hashmi A. Stephen K. 
Published: August 2013

AbstractGold carbenes generated via 1,2‐migration of a propargylic ester group can be transferred over a tethered alkyne. The use of aromatic backbones leads after a 1,7‐carbene transfer to a benzyl‐stabilized carbene as intermediate. A 1,2‐shift of a methyl group delivers vinyl‐substituted β‐naphthol derivatives as the final products.magnified image
Association of gestational maternal hypothyroxinemia and increased autism risk
Authors: Román Gustavo C. , Ghassabian Akhgar , Bongers‐Schokking Jacoba J. , Jaddoe Vincent W. V. , Hofman Albert , de Rijke Yolanda B. , Verhulst Frank C. , Tiemeier Henning 
Published: August 2013

ObjectiveTransient gestational hypothyroxinemia in rodents induces cortical neuronal migration brain lesions resembling those of autism. We investigated the association between maternal hypothyroxinemia (gestational weeks 6–18) and autistic symptoms in children.MethodsThe mother‐and‐child cohort of the Generation R Study (Rotterdam, the Netherlands) began prenatal enrollment between 2002 and 2006. At a mean gestational age of 13.4 weeks (standard deviation = 1.9, range = 5.9–17.9), maternal thyroid function tests (serum thyrotropin [TSH], free thyroxine [fT4], and thyroid peroxidase [TPO] antibodies) were assessed in 5,100 women. We defined severe maternal hypothyroxinemia as fT4 < 5th percentile with normal TSH. Six years later, parents reported behavioral and emotional symptoms in 4,039 children (79%) using the Pervasive Developmental Problems (PDP) subscale of the Child Behavior Checklist and/or the Social Responsiveness Scale (SRS). We defined a probable autistic child by a PDP score > 98th percentile and SRS score in the top 5% of the sample (n = 81, 2.0%).ResultsSevere maternal hypothyroxinemia (n = 136) was associated with an almost 4‐fold increase in the odds of having a probable autistic child (adjusted odds ratio = 3.89, 95% confidence interval [CI] = 1.83–8.20, p < 0.001). Using PDP scores, children of mothers with severe hypothyroxinemia had higher scores of autistic symptoms by age 6 years (adjusted B = 0.23, 95% CI = 0.03–0.37); SRS results were similar. No risk was found for children of TPO‐antibody–positive mothers (n = 308).InterpretationWe found a consistent association between severe, early gestation maternal hypothyroxinemia and autistic symptoms in offspring. Findings are concordant with epidemiological, biological, and experimental data on autism. Although these findings cannot establish causality, they open the possibility of preventive interventions. Ann Neurol 2013;74:733–742
Structural, viscoelastic, and vulcanization study of sponge ethylene–propylene–diene monomer composites with various carbon black loadings
Authors: Bashir M. Arshad , Iqbal Nadeem , Shahid Mohammad , Quratulain  , Ahmed Riaz 
Published: August 2013

ABSTRACTIn this article, we report the effect of various carbon nanoparticle concentrations on the structural, curing, tan δ, viscosity variation during vulcanization, thermal, and mechanical characteristics of ethylene–propylene–diene monomer polymer sponge composites. The purpose of this study was to develop high‐strength, foamy‐structure polymer composites with an optimum filler to matrix ratio for advanced engineering applications. We observed that the structural, vulcanization, viscoelastic, and mechanical properties of the fabricated composites were efficiently influenced with the progressive addition of carbon content in the rubber matrix. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39423.
Nanomechanical mapping of glass fiber reinforced polymer composites using atomic force acoustic microscopy
Authors: Zhou Xilong , Fu Ji , Li Yingwei , Li Faxin 
Published: August 2013

ABSTRACTIn this work, a dual‐frequency resonance tracking (DFRT) method was applied on atomic force acoustic microscopy (AFAM) and high‐resolution, quantitative nanomechanical mapping of a glass fiber–reinforced polymer composites (GFRP) was realized. Results show that even using the single‐frequency AFAM, the fiber, and epoxy can give very good contrast in amplitude images. The modulus mapping result on GFRP by DFRT AFAM was compared with that by dynamic nanoindentation, and it is found that DFRT AFAM can map the elastic modulus with high spatial resolution and more reliable results. The interface of GFRP was especially investigated using a 2 μm × 2 μm scanning area. Finite element analysis was implemented to investigate the effect of tip radius and the applied pressing force on the interface measurement using a sharp “interface”. By setting a linear‐modulus‐varied interface with finite width in finite element analysis (FEA), similar comparison between FEA and AFAM experimental results was also implemented. The average interface width is determined to be 476 nm based on the high‐resolution modulus image, indicating that AFAM is a powerful method for nanoscale interface characterization. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39800.
Characterization of the bacterioplankton community and its antibiotic resistance genes in the Baltic Sea
Authors: Tiirik Kertu , Nõlvak Hiie , Oopkaup Kristjan , Truu Marika , Preem Jens‐Konrad , Heinaru Ain , Truu Jaak 
Published: August 2013

AbstractThe residues from human environments often contain antibiotics and antibiotic resistance genes (ARGs) that can contaminate natural environments; the clearest consequence of that is the selection of antibiotic‐resistant bacteria. The Baltic Sea is the second largest isolated brackish water reservoir on Earth, serving as a drainage area for people in 14 countries, which differ from one another in antibiotic use and sewage treatment policies. The aim of this study was to characterize the bacterioplankton structure and quantify ARGs (tetA, tetB, tetM, ermB, sul1, blaSHV, and ampC) within the bacterioplankton community of the Baltic Sea. Quantitative polymerase chain reaction was applied to quantify ARGs from four different sampling sites of the Baltic Sea over 2 years, and the bacterial communities were profiled sequencing the V6 region of the 16S rRNA gene on Illumina HiSeq2000. The results revealed that all the resistance genes targeted in the study were detectable from the Baltic Sea bacterioplankton. The percentage of tetA, tetB, tetM, ermB, and sul1 genes in the sea bacterial community varied between 0.0077% and 0.1089%, 0.0003% and 0.0019%, 0.0001% and 0.0105%, 0% and 0.0136%, and 0.0001% and 0.0438%, respectively. The most numerous ARG detected was the tetA gene and this gene also had the highest proportion in the whole microbial community. A strong association between bacterioplankton ARGs’ abundance data and community phylogenetic composition was found, implying that the abundance of most of the studied ARGs in the Baltic Sea is determined by fluctuations in its bacterial community structure.
Adaptation of Dekkera bruxellensis to lignocellulose‐based substrate
Authors: Tiukova Ievgeniia A. , de Barros Pita Will , Sundell David , Haddad Momeni Majid , Horn Svein Jarle , Ståhlberg Jerry , de Morais Marcos Antonio , Passoth Volkmar 
Published: August 2013

AbstractAdaptation of Dekkera bruxellensis to lignocellulose hydrolysate was investigated. Cells of D. bruxellensis were grown for 72 and 192 H in batch and continuous culture, respectively (adapted cells). Cultivations in semisynthetic medium were run as controls (nonadapted cells). To test the adaptation, cells from these cultures were reinoculated in the lignocellulose medium, and growth and ethanol production characteristics were monitored. Cells adapted to lignocellulose hydrolysate had a shorter lag phase, grew faster, and produced a higher ethanol concentration as compared with nonadapted cells. A stability test showed that after cultivation in rich medium, cells partially lost the adapted phenotype but still showed faster growth and higher ethanol production as compared with nonadapted cells. Because alcohol dehydrogenase genes have been described to be involved in the adaptation to furfural in Saccharomyces cerevisiae, an analogous mechanism of adaptation to lignocelluloses hydrolysate of D. bruxellensis was hypothesized. However, gene expression analysis showed that genes homologous to S. cerevisiae ADH1 were not involved in the adaptation to lignocelluloses hydrolysate in D. bruxellensis.
Utility of noninvasive biomatrices in pharmacokinetic studies
Authors: Raju Kanumuri Siva Rama , Taneja Isha , Singh Sheelendra Pratap , Wahajuddin  
Published: August 2013

ABSTRACTBlood and plasma are the biomatrices traditionally used for drug monitoring and their pharmacokinetic profiling. Blood is the circulating fluid in contact with all organs and tissues of body and thus is the most representative fluid for measuring systemic drug levels. However, venipuncture suffers from the caveat of being an invasive technique which often makes people reluctant to participate in clinical studies. Thus, there is a need for noninvasive bio‐fluids that are ethically appropriate, cost‐efficient and toxicologically relevant. These alternate bio‐fluids may prove clinically useful as alternatives to plasma/serum in therapeutic drug monitoring, pharmacokinetic and toxicokinetic studies, doping control in sports medicine and to monitor local adverse effects. These may be of particular interest in the case of special population groups such as neonates, children, the elderly, terminally ill patients and pregnant or lactating women, and offer the advantage of circumvention of the demand for specialized personnel for sample collection. This review describes such noninvasive bio‐fluids (saliva, sweat, tears and milk) that have been considered for pharmacokinetic drug analysis, emphasizing their sample preparation, its associated difficulties and their correlation with plasma. Copyright © 2013 John Wiley & Sons, Ltd.
Virtual interactive e‐learning application: An evaluation of the student satisfaction
Authors: Violante Maria Grazia , Vezzetti Enrico 
Published: August 2013

ABSTRACTIn a web‐based learning environment, interactivity has been referred to as the most important element for successful e‐learning. This article presents the production cycle of an interactive medical device, namely a virtual 3D electroencephalogram, and the study conducted to measure the students' satisfaction of the learning application based on Kano's quality model. The web‐based interactive learning application introduces unique elements of interactivity with the learning content, specifically designed to train biomedical engineering students at the use of the medical device. The results of a post‐deployment student survey suggest that the visual and interactive features embedded in the application have the potential to induce positive satisfaction of users. The proposed approach may serve as reference for the correct design of similar learning applications not only in the biomedical engineering context but also outside the realms of engineering sciences. © 2013 Wiley Periodicals, Inc. Comput Appl Eng Educ 23:72–91, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21580
CoLFDImaP: A web‐based tool for teaching of FPGA‐based digital image processing in undergraduate courses
Authors: Garcia I. , Guzmán‐Ramírez E. , Pacheco C. 
Published: August 2013

ABSTRACTThe majority of academic tools for supporting the collaboration between students in Computer Science education have mainly incorporated functionalities for sharing documents and enabling discussions about specific topics. However, nowadays it has never been more imperative for educators to understand how to adapt new functionalities and technologies into real teaching contexts to improve knowledge construction; web‐based real‐time experimentation under a collaborative environment can be a good solution. This article presents a web‐based tool, the Collaborative Lab for FPGA‐based Digital Image Processing, that has been applied as a teaching aid in an undergraduate course using digital image processing and Field Programmable Gate Array (FPGA) technologies. Finally, collaborative experimentation in diverse digital image processing practices is shown. © 2013 Wiley Periodicals, Inc. Comput Appl Eng Educ 23:92–108, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21581
Robust multi‐level partition of unity implicits from triangular meshes
Authors: Li Weitao , Zhou Yuanfeng , Zhang Caiming , Li Xuemei 
Published: August 2013

ABSTRACTThis paper presents a new robust multi‐level partition of unity (MPU) method, which constructs an implicit surface from a triangular mesh via the new error metric between the mesh and the implicit surface. The new error metric employs a weighted function of inner points and vertices of a triangle to fit an implicit surface, which can control the approximation error between the surface and vertices of the triangle. Furthermore, it is applied to the MPU method by utilizing the dual graph of a triangular mesh, and the general quadric implicit surface is used for surface representation. Compared with the MPU method, the new method generates fewer subdivision cells with the same approximation error and performs more steadily especially when given triangular mesh with fewer vertices. Copyright © 2013 John Wiley & Sons, Ltd.
Fast animation of debris flow with mixed adaptive grid refinement
Authors: Wang Changbo , Zhang Qiang , Kong Fanlong , Gao Yusheng 
Published: August 2013

AbstractAnimating debris flow is one of the most challenging tasks in computer graphics, because of its complex dynamic mechanism and the interaction between flows and solids in so large scale region. The difficulty focuses on how to resolve the contradiction between lower computational load and higher request of animating quality. A highly effective method of modeling and animating of debris flow with adaptive grid is presented. First, the debris flow is modeled as Bingham plastic fluid with view‐dependent adaptive grid that is adopted to model the flow volume, and the boundless grids can cover the large scale region of debris flow. Then the mixed grids are built for confluent flows, and the two‐way coupling interaction between flows and environment is considered. After extracting the debris flow surface, adaptive surface tension combining wave particles equation is used to enhance the details and sprays are generated by particles considering the interaction between two fluid volumes. Finally, different dynamic realistic scenes with debris flow are successfully animating at interactive rates. Copyright © 2013 John Wiley & Sons, Ltd.
Effects of FlAsH/Tetracysteine (TC) Tag on PrP Proteolysis and PrPres Formation by TC‐Scanning
Authors: Taguchi Yuzuru , Hohsfield Lindsay A. , Hollister Jason R. , Baron Gerald S. 
Published: August 2013

AbstractProtein–protein interactions associated with proteolytic processing and aggregation are integral to normal and pathological aspects of prion protein (PrP) biology. Characterization of these interactions requires the identification of amino acid residues involved. The FlAsH/tetracysteine (FlAsH/TC) tag is a small fluorescent tag amenable to insertion at internal sites in proteins. In this study, we used serial FlAsH/TC insertions (TC‐scanning) as a probe to characterize sites of protein–protein interaction between PrP and other molecules. To explore this application in the context of substrate–protease interactions, we analyzed the effect of FlAsH/TC insertions on proteolysis of cellular prion protein (PrPsen) in in vitro reactions and generation of the C1 metabolic fragment of PrPsen in live neuroblastoma cells. The influence of FlAsH/TC insertion was evaluated by TC‐scanning across the cleavage sites of each protease. The results showed that FlAsH/TC inhibited protease cleavage only within limited ranges of the cleavage sites, which varied from about one to six residues in width, depending on the protease, providing an estimate of the PrP residues interacting with each protease. TC‐scanning was also used to probe a different type of protein–protein interaction: the conformational conversion of FlAsH‐PrPsen to the prion disease‐associated isoform, PrPres. PrP constructs with FlAsH/TC insertions at residues 90–96 but not 97–101 were converted to FlAsH‐PrPres, identifying a boundary separating loosely versus compactly folded regions of PrPres. Our observations demonstrate that TC‐scanning with the FlAsH/TC tag can be a versatile method for probing protein–protein interactions and folding processes.
Fundamental Insight into the Substrate‐Dependent Ripening of Monodisperse Clusters
Authors: Fukamori Yves , König Michael , Yoon Bokwon , Wang Bo , Esch Friedrich , Heiz Ueli , Landman Uzi 
Published: August 2013

AbstractSintering is one of the major routes for the deactivation of surface‐supported catalytic particles in heterogeneous catalysis. The two mechanisms that are responsible for such coarsening phenomena are Ostwald ripening, in which larger clusters tend to grow at the expense of smaller ones, and Smoluchowski ripening, in which entire clusters diffuse and coalesce. The sintering properties of cluster‐assembled materials can be influenced by tuning the interactions between the particle and the substrate. To explore the fundamental factors that control cluster‐ripening mechanisms, we deposited truly monodisperse Pd clusters onto three different model catalysts: bare Rh(1 1 1), graphene‐Moiré films that were grown on Rh(1 1 1) and Ru(0 0 0 1), and a hexagonal boron‐nitride film that was grown on Rh(1 1 1). The evolution of particle size and density was tracked by high‐resolution scanning tunneling microscopy. The principal microscopic mechanisms that govern the ripening processes on each of these three substrates have been determined from thorough analyses of the cluster heights and size distributions. The ripening mechanisms were related to the distinct cluster‐adsorption and atom‐detachment energies that were obtained from first‐principle calculations. These results elucidate the ripening processes and underlie the formulation of a strategy for optimizing cluster stability against ripening, where both, the binding of the clusters to the surface and that of the individual atoms, must be controlled. Such tuning of the interactions may be achieved through the judicious selection of surfaces with laterally modulated wettability.
Conceptual foundations of diffusion in magnetic resonance
Authors: Koay Cheng Guan , Özarslan Evren 
Published: August 2013

ABSTRACTA thorough review of the q‐space technique is presented starting from a discussion of Fick's laws. The work presented here is primarily conceptual, theoretical, and hopefully pedagogical. We offered the notion of molecular concentration to unify Fick's laws and diffusion MRI within a coherent conceptual framework. The fundamental relationship between diffusion MRI and Fick's laws is carefully established. The conceptual and theoretical basis of the q‐space technique is investigated from first principles. © 2013 Wiley Periodicals, Inc. Concepts Magn Reson Part A 42A: 116‐129, 2013.
A slice‐wise latent structure regression method for the analysis of functional magnetic resonance imaging data
Authors: Fayyaz Ahmad , Chaudhary Safee Ullah , Kim Sung‐Ho , Park Hyunwook 
Published: August 2013

ABSTRACTWe introduce a novel slice‐wise latent structure regression (LSR) method for the analysis of functional magnetic resonance imaging (fMRI) data instead of the conventional voxel‐wise generalized least squares (GLS) method. LSR method is designed for application to data sets from slices where fMRI responses (voxels Y* of a slice) are highly correlated with the design matrix X*. Also, we compared the performances of LSR, principal component regression (PCR), and GLS methods in terms of model parameters using experimental fMRI data. The LSR method exhibits an enhanced predictive ability and model coefficients as compared to the PCR and GLS methods. © 2013 Wiley Periodicals, Inc. Concepts Magn Reson Part A 42A: 130‐139, 2013.
Anomalous Property of Ag(BO2)2 Hyperhalogen: Does Spin–Orbit Coupling Matter?
Authors: Chen Hui , Kong Xiang‐Yu , Zheng Weijun , Yao Jiannian , Kandalam Anil K. , Jena Puru 
Published: August 2013

AbstractHyperhalogens were recently identified as a new class of highly electronagative species which are composed of metals and superhalogens. In this work, high‐level theoretical calculations and photoelectron spectroscopy experiments are systematically conducted to investigate a series of coinage‐metal‐containing hyperhalogen anions, Cu(BO2)2−, Ag(BO2)2−, and Au(BO2)2−. The vertical electron detachment energy (VDE) of Ag(BO2)2− is anomalously higher than those of Au(BO2)2− and Cu(BO2)2−. In quantitative agreement with the experiment, high‐level ab initio calculations reveal that spin–orbit coupling (SOC) lowers the VDE of Au(BO2)2− significantly. The sizable magnitude of about 0.5 eV of SOC effect on the VDE of Au(BO2)2− demonstrates that SOC plays an important role in the electronic structure of gold hyperhalogens. This study represents a new paradigm for relativistic electronic structure calculations for the one‐electron‐removal process of ionic AuIL2 complexes, which is characterized by a substantial SOC effect.