bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective Oxidation of Methanol to Hydrogen over Gold Catalysts Promoted by Alkaline‐Earth‐Metal and Lanthanum Oxides
Authors: Hereijgers Bart P. C. , Weckhuysen Bert M. 
Published: July 2009

AbstractA series of alumina‐supported gold catalysts was investigated for the CO‐free production of hydrogen by partial oxidation of methanol. The addition of alkaline‐earth metal oxide promoters resulted in a significant improvement of the catalytic performance. The methanol conversion was ca. 85 % with all studied catalyst materials, however, the selectivity for hydrogen increased from 15 % to 51 % when going from the unpromoted to a BaO‐promoted catalyst. The formation of the undesired byproducts CO, methane, and dimethyl ether was considerably reduced as well. The observed trend in catalyst performance follows the trend in increasing basicity of the studied promoter elements, indicating a chemical effect of the promoter material. Superior catalytic performance, in terms of H2 and CO selectivity, was obtained with a Au/La2O3 catalyst. At 300 °C the hydrogen selectivity reached 80 % with only 2 % CO formation, and the catalyst displayed a stable performance over at least 24 h on‐stream. Furthermore, the formation of CO was found to be independent of the oxygen concentration in the feed. The commercial lanthanum oxide used in this study had a low specific surface area, which led to the formation of relative large gold particles. Therefore, the catalytic activity could be enhanced by decreasing the gold particle size through deposition on lanthanum oxide supported on high‐surface‐area alumina.
Structural generation of two integrator loop filters using CDTAs and grounded capacitors
Authors: Tangsrirat Worapong , Pukkalanun Tattaya 
Published: July 2009

AbstractA versatile family of two integrator loop filter structures using current differencing transconductance amplifiers (CDTAs) and grounded capacitors is generated. The basic filter building blocks consist of current proportional blocks, current lossless integrators and a current lossy integrator based on the use of CDTAs as the major active components. It is demonstrated that the derived filter structures can realize a general class of second‐order current transfer functions. Since the resulting structures contain only CDTAs and grounded capacitors, they are general and very appropriate for integration, cascading and electronic tuning. The influences of the CDTA non‐idealities are also discussed. The functionality of the resulting filters has been verified by simulation results. Copyright © 2009 John Wiley & Sons, Ltd.
Mechanical computation in neurons
Authors: Laishram Jummi , Avossa Daniela , Shahapure Rajesh , Torre Vincent 
Published: July 2009

AbstractGrowth cones are the main motile structures located at the tip of neurites and are composed of a lamellipodium from which thin filopodia emerge. In this article, we analyzed the kinetics and dynamics of growth cones with the aim to understand two major issues: first, the strategy used by filopodia and lamellipodia during their exploration and navigation; second, what kind of mechanical problems neurons need to solve during their operation. In the developing nervous system and in the adult brain, neurons constantly need to solve mechanical problems. Growth cones must decide how to explore the environment and in which direction to grow; they also need to establish the appropriate contacts, to avoid obstacles and to determine how much force to exert. Here, we show that in sparse cultures, filopodia grow and retract following statistical patterns, nearly optimal for an efficient exploration of the environment. In a dense culture, filopodia exploration is still present although significantly reduced. Analysis on 1271, 6432, and 185 pairs of filopodia of DRG, PC12 and Hippocampal neurons respectively showed that the correlation coefficient |ρ| of the growth of more than 50% of filopodia pairs was >0.15. From a computational point of view, filopodia and lamellipodia motion can be described by a random process in which errors are corrected by efficient feedback loops. This article argues that neurons not only process sensory signals, but also solve mechanical problems throughout their entire lifespan, from the early stages of embryogenesis to adulthood. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009
DC within the pregnant mouse uterus influence growth and functional properties of uterine NK cells
Authors: Karsten Christian M. , Behrends Jochen , Wagner Arnika K. , Fuchs Franca , Figge Julia , Schmudde Inken , Hellberg Lars , Kruse Andrea 
Published: July 2009

AbstractThe vascular addressins mucosal addressin cell adhesion molecule‐1, P‐selectin and ICAM‐1 permit α4β7‐integrin‐expressing DC, especially those of the myeloid lineage (CD11c+CD11b+ DC), to access the pregnant mouse uterus. Injection of blocking monoclonal antibodies against mucosal addressin cell adhesion molecule‐1 in P‐selectin−/− mice or experimental approaches with β7‐integrin−/− or ICAM‐1−/− mice revealed that limited access or absence of CD11c+CD11b+ DC at the maternal/fetal interface negatively affects the frequency, size and functional properties of uterine NK (uNK) cells. Adoptive transfer of DC obtained from WT mice into β7‐integrin−/− mice abrogates these effects and emphasizes the importance of DC in uNK cell differentiation. Interestingly, those implantation sites lacking CD11c+CD11b+ DC are characterized by decreased IL‐15 and IL‐12 mRNA and/or protein levels. Chronic administration of IL‐15 in these mice gives rise to uNK cell numbers and size comparable to those of WT mice, whereas additional injection of IL‐12 positively affects the IFN‐γ expression of uNK cells. Real‐time RT‐PCR and protein arrays performed with isolated uterine DC underline the role of DC as a source of IL‐15 and IL‐12 in the pregnant mouse uterus.
Adventures in the Coordination Chemistry of Di‐2‐pyridyl Ketone and Related Ligands: From High‐Spin Molecules and Single‐Molecule Magnets to Coordination Polymers, and from Structural Aesthetics to an Exciting New Reactivity Chemistry of Coordinated Ligands
Authors: Stamatatos Theocharis C. , Efthymiou Constantinos G. , Stoumpos Constantinos C. , Perlepes Spyros P. 
Published: July 2009

AbstractThe coordination chemistry of di‐2‐pyridyl ketone and related ligands is reviewed. An outline of the variety of such ligands is presented. References are given to methods for the synthesis of ligands that are not available on the market. The activation of the carbonyl group(s) of some of the ligands towards further reactions seems to be an emergent area of synthetic inorganic chemistry. The coordination chemistry of each ligand with metals is briefly described. Emphasis is placed on structural features and physical properties (mainly magnetic) of the resulting metal clusters and coordination polymers. The structural diversity of the complexes stems from the ability of the deprotonated diol‐ or hemiketal‐type ligands to adopt a variety of bridging coordination modes depending on the number of carbonyl groups, the nature of the extra donor groups in the molecule and on the reaction conditions. Employment of a second organic or inorganic ligand in this chemistry gives an extraordinary structural flexibility in the resulting mixed‐ligand systems. The initial use of 1,1′‐carbonyldiimidazole and 1,1′‐oxalyldiimidazole in copper(II) chemistry, which leads to unprecedented coordination polymers containing alcoholysis and/or hydrolysis “fragments” of the ligands, is also illustrated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Complexes of Four‐Membered Group 13 Metal(I) N‐Heterocyclic Carbene Analogues with Metal Carbonyl Fragments
Authors: Jones Cameron , Stasch Andreas , Moxey Graeme J. , Junk Peter C. , Deacon Glen B. 
Published: July 2009

AbstractThe four‐membered gallium(I) and indium(I) heterocycles, [:M(Giso)] (M = Ga or In; Giso = {[N(Ar)]2CN(C6H11)2}–, Ar = C6H3iPr2‐2,6), were treated with a series of transition metal carbonyl complexes. These reactions afforded the complexes [Fe(CO)4{Ga(Giso)}], [(CO)3Co{μ‐Ga(Giso)}2Co(CO)3], [Ru(CO)2(PPh3)2{M(Giso)}] and [CpMo(CO)2{[(Giso)Ga]2OH}], which were crystallographically and/or spectroscopically characterized. The results of the study show that the two heterocycles can act as σ‐donor ligands, but they are not as nucleophilic as, for example, group 13 diyls, :MR (M = Ga or In; R = alkyl, aryl, etc.). In addition, the degree of π‐back‐bonding in their metal carbonyl complexes does not appear to be significant.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Synthesis of Modular Headgroup Conjugates Corresponding to All Seven Phosphatidylinositol Polyphosphate Isomers for Convenient Probe Generation
Authors: Gong Denghuang , Bostic Heidi E. , Smith Matthew D. , Best Michael D. 
Published: July 2009

AbstractPhosphatidylinositol polyphosphate lipids (PIPns) play key roles in important biological pathways, and defects in the signaling activities of these molecules have been implicated in a number of disease states. As such, it is necessary to understand the complex roles of these lipids in biological pathways, which often involve their actions as site‐specific ligands that recruit receptors to the surfaces of cellular membranes. However, the complex structures of PIPn family members, of which seven biologically active isomers exist, complicate studies. Derivatized analogs of the PIPn structures are beneficial as chemical tools for elucidating signaling and binding activities. Herein, we present an efficient approach to probe the generation in which amino conjugates of PIPn headgroups can be conveniently functionalized in the final step of the synthesis to obtain a number of derivatized analogs of use for different studies. In addition to the application of this strategy to generate PI‐(4,5)‐P2 headgroup probes, we also report the synthesis of PIPn–amine conjugates corresponding to all seven naturally existing isomers. This approach will be invaluable for generating the range of probe structures that is required to elucidate the intricacies of PIPn signaling. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Modular Synthesis of Novel Chiral Phosphorous Triamides Based on (S)‐N‐(Pyrrolidin‐2‐ylmethyl)aniline and Their Application in Asymmetric Catalysis
Authors: Barta Katalin , Hölscher Markus , Franciò Giancarlo , Leitner Walter 
Published: July 2009

AbstractA set of new P‐chiral phosphorous triamides (PTAs) based on the (S)‐N‐(pyrrolidin‐2‐ylmethyl)aniline backbone was prepared by modular synthetic procedures. The chirality at phosphorus can be controlled to a large extent by the synthetic route, and high diastereomeric purities were achieved for most of the reported ligands. This ligand family was evaluated in the copper‐catalysed Michael addition of diethylzinc to cyclohex‐2‐enone, and moderate enantioselectivities were achieved. In the asymmetric nickel‐catalysed hydrovinylation of styrene, good conversions and chemoselectivities, together with promising enantioselectivities of up to 60 %, were obtained with the new PTA ligands even at relatively high reaction temperatures.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Nd(OTf)3‐Catalyzed Cascade Reactions of Vinylidenecyclopropanes with Enynol: A New Method for the Construction of the 5–7–6 Tricyclic Framework and Its Scope and Limitations
Authors: Yao Liang‐Feng , Shi Min 
Published: July 2009

AbstractWe report in this paper a Lewis acid [Nd(OTf)3]‐catalyzed protocol to construct compounds containing a 5–7–6 tricyclic framework in good yield from readily accessible starting materials vinylidenecyclopropanes (VDCPs) 1 and enynols 2a–c under mild conditions. Upon examination of the scope and limitations of this reaction, it was found that the corresponding highly functionalized cyclopentane derivatives could be formed in good yields from the reaction VDCPs 1 and enol 2e or dienol 2c under identical conditions.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Microchip electrophoresis in low‐temperature co‐fired ceramics technology with contactless conductivity measurement
Authors: Fercher Georg , Smetana Walter , Vellekoop Michiel J. 
Published: July 2009

AbstractIn this paper a novel micromachined contactless conductivity CE device produced in low temperature co‐fired ceramics (LTCC) is introduced. The application of LTCC multilayer technology provides a promising method for the contactless detection of conductive compounds because of its increased dielectric constant compared with glass or plastics. The capacitive coupling of the excitation signal into the microchannel across the LTCC substrate is improved, resulting in better detection sensitivity. Two silver electrodes located externally at opposite sides at the end of the separation channel act as detector. Impedance variations in the channel are measured without galvanic contact between electrodes and fluid. Inorganic ions are separated in less than 1 min with this novel ceramic device. The limit of detection is 10 μM for potassium.
Stability and identification for rational approximation of frequency response function of unbounded soil
Authors: Du Xiuli , Zhao Mi 
Published: July 2009

AbstractExact representation of unbounded soil contains the single output–single input relationship between force and displacement in the physical or transformed space. This relationship is a global convolution integral in the time domain. Rational approximation to its frequency response function (frequency‐domain convolution kernel) in the frequency domain, which is then realized into the time domain as a lumped‐parameter model or recursive formula, is an effective method to obtain the temporally local representation of unbounded soil. Stability and identification for the rational approximation are studied in this paper. A necessary and sufficient stability condition is presented based on the stability theory of linear system. A parameter identification method is further developed by directly solving a nonlinear least‐squares fitting problem using the hybrid genetic‐simplex optimization algorithm, in which the proposed stability condition as constraint is enforced by the penalty function method. The stability is thus guaranteed a priori. The infrequent and undesirable resonance phenomenon in stable system is also discussed. The proposed stability condition and identification method are verified by several dynamic soil–structure‐interaction examples. Copyright © 2009 John Wiley & Sons, Ltd.
Caring for a sibling with anorexia nervosa: A qualitative study
Authors: Dimitropoulos Gina , Klopfer Kristina , Lazar Lorena , Schacter Reva 
Published: July 2009

AbstractObjectiveFew studies have explored eating disorders from the perspective of non‐affected siblings. The aim of this investigation was to explore the unique experiences and challenges of siblings of women with anorexia nervosa (AN).MethodTwelve semi‐structured qualitative interviews were conducted with sibling participants to ascertain their perspective of caring for a sister with chronic AN.ResultsQualitative analyses gleaned six themes: (1) the sibling role as protector and mediator; (2) familial factors that influence and reinforce these sibling roles; (3) consequences and benefits of AN to non‐affected sibling; (4) coping strategies; (5) current and future intentions of caregiving and (6) professional and informal support.DiscussionThe findings from this qualitative study provide a window into the perceptions, feelings, and roles of siblings of women afflicted with AN. An intervention guided by the elicited themes may facilitate family functioning that is more adaptive for both siblings. Copyright © 2009 John Wiley & Sons, Ltd and Eating Disorders Association.
A boundary condition for arbitrary shaped inlets in lattice–Boltzmann simulations
Authors: Mattila K. , Hyväluoma J. , Folarin A. A. , Rossi T. 
Published: July 2009

AbstractWe introduce a mass‐flux‐based inlet boundary condition for the lattice‐Boltzmann method. The proposed boundary condition requires minimal amount of boundary data, it produces a steady‐state velocity field which is accurate close to the inlet even for arbitrary inlet geometries, and yet it is simple to implement. We demonstrate its capability for both simple and complex inlet geometries by numerical experiments. For simple inlet geometries, we show that the boundary condition provides very accurate inlet velocities when Re≲1. Even with moderate Reynolds number, the inlet velocities are accurate for practical purposes. Furthermore, the potential of our boundary condition to produce inlet velocities which convincingly adapt to complex inlet geometries is highlighted with two specific examples. Copyright © 2009 John Wiley & Sons, Ltd.
Nonlinear system identification using radial basis functions
Authors: Mokhasi Paritosh , Rempfer Dietmar 
Published: July 2009

AbstractFocussing on applications to fluid flow phenomena, we are interested in developing dynamical system models that are based on the discrete multivariate time series information only. A method based on radial basis functions and linear multi‐step methods is used to construct continuous nonlinear models that approximate the original dynamical system. Information, such as the structure of the original system, is incorporated into the models through weak constraints. The formulation of the model and its advantages associated with modeling is described. Different examples are presented that highlight the various characteristics of the model and its effectiveness in dealing with various problems encountered in fluid flow problems. Copyright © 2009 John Wiley & Sons, Ltd.
Modeling and prediction of chaotic systems with artificial neural networks
Authors: Woolley Jonathan W. , Agarwal P. K. , Baker John 
Published: July 2009

AbstractThis study of chaotic systems and their prediction is motivated by the fact that many phenomena, both natural and man‐made, are of a chaotic nature. Such phenomena include but are not limited to earthquakes, laser systems, epileptic seizures, combustion, and weather patterns. These phenomena have previously been thought to be unpredictable. However, it is indeed possible to predict time series generated by chaotic systems. The primary objective of this study is to develop a system that would train the artificial neural network (ANN) and then predict the future data of the process. In the present application, the chosen chaotic data set was obtained by solving Lorenz's equations. To predict the future data, the concept of a multilayer feed‐forward ANN with nonlinear auto‐regressive moving averages with exogenous input is used. A Backpropagation algorithm is used to train the network for the chaotic data. The final updated weights from the trained network were then used for the prediction of the future values of the system. Lyapunov exponents, phase diagrams and statistical analyses were used to evaluate the neural network output. A correlation of 94% and a negative Lyapunov exponent indicate that the results obtained from ANN are in good agreement with the actual values. Copyright © 2009 John Wiley & Sons, Ltd.
Spatial‐temporal dynamics of cortical activity underlying reaching and grasping
Authors: Virji‐Babul Naznin , Moiseev Alexander , Cheung Teresa , Weeks Daniel , Cheyne Douglas , Ribary Urs 
Published: July 2009

AbstractHow humans understand the actions and intentions of others remains poorly understood. Here we report the results of a magnetoencephalography (MEG) experiment to determine the temporal dynamics and spatial distribution of brain regions activated during execution and observation of a reach to grasp motion using real world stimuli. We show that although both conditions activate similar brain areas, there are distinct differences in the timing, pattern and location of activation. Specifically, observation of motion revealed a right hemisphere dominance with activation involving a network of regions that include frontal, temporal and parietal areas. In addition, the latencies of activation showed a task specific pattern. During movement execution, the earliest activation was observed in the left premotor and somatosensory regions, followed closely by left primary motor and STG at the time of movement onset. During observation, there was a shift in the timing of activation with the earliest activity occurring in the right temporal region followed by activity in the left motor areas. Activity within these areas was also characterized by a shift to a lower frequency in comparison with action execution. These results add to the growing body of evidence indicating a complex interaction within a distributed network involving motor and nonmotor regions during observation of real actions. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.
Inequality of opportunities in health in France: a first pass
Authors: Trannoy Alain , Tubeuf Sandy , Jusot Florence , Devaux Marion 
Published: July 2009

AbstractThis article analyses the role played by childhood circumstances, especially social and family background in explaining health status among older adults. We explore the hypothesis of an intergenerational transmission of health inequalities using the French part of SHARE. As the impact of both social background and parents' health on health status in adulthood represents circumstances independent of individual responsibility, this study allows us testing the existence in France of inequalities of opportunity in health related to family and social background. Empirically, our study relies on tests of stochastic dominance at first order and multivariate regressions, supplemented by a counterfactual analysis to evaluate the long‐lasting impact of childhood conditions on inequality in health. Allocating the best circumstances in both parents' socioeconomic status and parents' health reduces inequality in health by an impressive 57% using the Gini coefficient. The mother's social status has a direct effect on the health of her offspring. By contrast, the effect on descendant's health from their father's social status is indirect only, which goes through the descendant's social status as an adult. There is also a strong effect of the father vital status on health in adulthood, revealing a selection effect. Copyright © 2009 John Wiley & Sons, Ltd.
Multiscale entropy approach to physiological fatigue during long‐term Web browsing
Authors: Hung C. H. , Jiang Bernard C. 
Published: July 2009

AbstractPhysiological fatigue during long‐term Web browsing was investigated by the entropy‐based method. A noninvasive instrument was used to gather 8‐hour continuous electrocardiography signals from subjects who were asked to answer the psychological fatigue questionnaire every 2 hours. These data were used to calculate the heart rate (HR), traditional sample entropy (SampEn), and multiscale entropy (MSE). HR decreased as the browsing task began, but increased slightly after 4.5 hours. The psychological fatigue score gradually increased, implying that more severe subjective fatigue was experienced as Web browsing proceeded. In contrast, the traditional SampEn first increased and then oscillated after 2.5 hours. The browsing time of 2.5 hours may be a clue to physiological fatigue. The MSE results showed that the cardiac dynamic systems of undergraduates and males were more complex than those of graduates and females, respectively. Thus, SampEn may have the potential for estimating physiological fatigue during long‐term Web browsing. © 2009 Wiley Periodicals, Inc.