bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generation and spatiotemporal evolution of optical vortices in femtosecond laser pulses
Authors: Toda Yasunori , Nagaoka Koshi , Shimatake Katsuhiro , Morita Ryuji 
Published: April 2009

AbstractTopology has become one of the key concepts allowing one to understand the intrinsic, qualitative properties of phenomena throughout various scientific fields. To date, this concept has been extended to the field of material science and technology. On the other hand, we can now utilize the spatially controlled light defined by the topology (so‐called “optical vortices”) in order to characterize the topological properties of materials. In particular, optical vortices in femtosecond pulses will be invaluable for advanced topological spectroscopy. In this work, the authors created femtosecond optical vortices using a spatial light modulator. Their spatiotemporal properties were evaluated using interferogram and correlation measurements. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(4): 39–46, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20791
Dynamic C‐V characteristic for a varactor load connected with a transmission line
Authors: Watanabe Takemi , Sangkrasin Apiruk , Matsumoto Fujihiko , Noguchi Yasuaki 
Published: April 2009

AbstractCrosstalk is induced by a reflected wave of a load connected with a transmission line. Thus, analysis of the reflected wave is important. The reflected wave generated from a nonlinear load is complicated. In order to estimate the complicated reflected wave, we measured the reflected and incident waves for the nonlinear load and estimated the dynamic C‐V characteristic, which explains the relation between the incident and reflected waves. This paper reports a simple experimental method of extracting reflected waves at a varactor load and presents estimates of the dynamic C‐V characteristic of the load. It is shown that the reflected voltage waves simulated using the dynamic C‐V characteristic agree with the measured results. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(4): 32–38, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20821
Operating principles of pin diodes
Authors: Takata Ikunori 
Published: April 2009

AbstractAnalytical models of the pin diode in a small‐current operation are not known yet. This article presents a simple analytical model of the pin diode operation with its confirmation by a numerical simulation. At the onset, carrier recombinations are not included for the sake of simplicity. The exact JF−VF characteristic $[J_{F} \propto \hbox{exp}(V_{F}/kT)]$ could have been induced only by accounting for the Boltzmann distribution of each carrier across the junctions and the diffusion current of each minority carrier in a p‐anode or n‐cathode. Based on this new model, the modifications of hole–electron densities product (nenh) across junctions, a rough estimation of the large operational current, its carrier distributions, and the effect of carrier recombination on the carrier distribution are plainly estimated and are also compared with the simulation results. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(4): 47–56, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20844
Remote surface modification of plastics by atmospheric barrier discharge
Authors: Yanagisawa Yuta , Yoshioka Yoshio 
Published: April 2009

AbstractThe surface modification by atmospheric pressure barrier discharge is effective in the improvement of adhesion performance of plastics. Remote plasma processing has several advantages over direct plasma processing. It is free from the problem of surface damage and charge accumulation and has larger freedom of setup of the system. However, it is necessary to improve the processing performances such as range of remote processing distance, reduction of contact angle, and so on.In this paper, we have investigated processing performances of the remote surface reforming. We used polyethylene film as the reforming object. It was found that the following are very effective as processing conditions: (1) use of nitrogen gas, (2) high‐speed gas flow, and (3) longer processing time. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(4): 1–8, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20861
Progressive CD127 down‐regulation correlates with increased apoptosis of CD8 T cells during chronic HIV‐1 infection
Authors: Zhang Shu‐Ye , Zhang Zheng , Fu Jun‐Liang , Kang Fu‐Biao , Xu Xiang‐Sheng , Nie Wei‐Min , Zhou Chun‐Bao , Zhao Min , Wang Fu‐Sheng 
Published: April 2009

AbstractChronic HIV‐1 infection can induce a significant decrease in CD127 expression on CD8 T cells, but the underlying mechanisms and immunological consequences are unclear. In this study, we investigated CD127 expression on CD8 T cells from a total of 51 HIV‐1‐infected subjects and 16 healthy individuals and analyzed the association between CD127 expression and CD8 T‐cell apoptosis in these HIV‐1‐infected subjects. We found that CD127 expression on total CD8 T cells was significantly down‐regulated, which was correlated with the increased CD8 T‐cell apoptosis and disease progression of chronic HIV‐1 infection. The in vitro addition of IL‐7 efficiently rescued the spontaneous apoptosis of CD8 T cells from HIV‐1‐infected individuals. IL‐7 stimulation also transiently down‐regulated CD127 expression, whereas some of the CD127− CD8 T cells regained CD127 expression soon after IL‐7 was retracted from the incubation medium. Thus, IL‐7 stimulation reduced apoptosis of both CD127+ and CD127−CD8 T cells to some degree. These data indicate that CD127 loss might impair IL‐7 signaling and increase CD8 T‐cell apoptosis during HIV‐1 infection. This study, therefore, will extend the notion that IL‐7 could be a good candidate for immunotherapy in HIV‐1‐infected patients.
Curing CNS autoimmune disease with myelin‐reactive Foxp3+ Treg
Authors: Stephens Leigh A. , Malpass Katy H. , Anderton Stephen M. 
Published: April 2009

AbstractThe potential use of CD4+Foxp3+ Treg as a cellular therapy for autoimmune disease is of great interest. For clinical translation, the key objective is to reverse established disease. Here we demonstrate that myelin basic protein (MBP)‐reactive CD4+CD25+ Treg from TCR Tg mice, but not polyclonal (non‐MBP‐reactive) Treg, can transfer efficient protection against MBP‐induced EAE when used either directly from donor mice, or after in vitro expansion. MBP‐reactive Treg transfer also showed some ability to improve recovery from EAE initiated by T cells recognizing a distinct CNS autoantigen, proteolipid protein. Importantly, we also demonstrate for the first time in the context of EAE that in vitro‐expanded naturally occurring MBP‐reactive Treg can prevent disease relapse when given after the onset of clinical EAE. Our study also contains data pertaining to the most effective Treg sub‐population in vivo (CD4+CD25+CD62Lhi) and shows that their potent suppressive effects reflect stable expression of Foxp3, although not CD25 or CD62L. Our data provide proof of the principle that Treg‐based therapies can cure CNS autoimmune disease, highlight the challenges for clinical translation and open new avenues for assessing how changing immune function via Treg activity might impact on neurodegeneration and repair.
The adaptive phenotype of cortical thymic epithelial cells
Authors: Boehm Thomas 
Published: April 2009

AbstractEpithelial cells in the thymus are required for positive and negative selection of developing thymocytes. Although medullary epithelial cells play a major role in negative selection owing to their facility of expressing peripheral self‐antigens, the adaptive features of cortical epithelial cells are largely unknown. A paper in this issue of the European Journal of Immunology shows that the putative serine protease Prss16 affects positive selection of a subset of CD4+ T cells. A survey of chordate genomes indicates that the Prss16 gene emerged in vertebrates as a paralogue of evolutionarily older members of the serine carboxypeptidase 28 family; thus, Prss16 is not associated with the appearance of the adaptive immune system and the thymus in jawed vertebrates. Nevertheless, it appears that Prss16 has later evolved as an essential contributor to the MHC class II peptide/ligand repertoire.
Cover Picture: Eur. J. Immunol. 4/09
Authors: Ghumra Ashfaq , Shi Jianguo , Mcintosh Richard S. , Rasmussen Ingunn B. , Braathen Ranveig , Johansen Finn‐Eirik , Sandlie Inger , Mongini Patricia K. , Areschoug Thomas , Lindahl Gunnar , Lewis Melanie J. , Woof Jenny M. , Pleass Richard J. 
Published: April 2009

AbstractThe cover image, provided by Ghumra et al. (pp. 1147–1156), shows two views of a molecular model of human dimeric IgA1 revealing residues predicted to be critical for interaction with human Fca/mR, a receptor with specificity for the Fc regions of IgA and IgM. The IgA heavy chains (tailpieces omitted) are shown in yellow, and the light chains in blue. The heavy chain residues proline 440 to phenylalanine 443 on the Ca3 domain of the IgA Fc region, implicated in hFca/mR interaction, are shown as red spheres. The J (joining) chain of the dimeric IgA is not included in the model, but the white dotted line in the lower view indicates a possible position.
Synthesis, Structure, and Ring‐Expansion Reactions of a 3‐Ferrocenyl‐Substituted 2H‐Azaphosphirene Tungsten Complex
Authors: Streubel Rainer , Beckmann Manuela , Neumann Christoph , Fankel Stefan , Helten Holger , Feier‐Iova Ovidiu , Jones Peter G. , Nieger Martin 
Published: April 2009

AbstractReaction ofC‐ferrocenyl‐substituted aminocarbene tungsten complex1with [bis(trimethylsilyl)methylene]chlorophosphane (2) and triethylamine yielded 2H‐azaphosphirene complex3in good yield. Reaction of complex3with aryl nitriles4a–c,N‐piperidinonitrile (4d), and acetonitrile (4e) in the presence of ferrocenium hexafluorophosphate yieldedregioselectively 2H‐1,4,2‐diazaphosphole complexes5a–ethrough single‐electron‐transfer‐induced ring expansion together with complex6in varying amounts; isolation of the latter failed. Apart from the NMR spectroscopic parameters of complexes1,3, and5a–e, cyclic voltammetric (1,3,5a–d), and single‐crystal X‐ray diffraction data (1,3, and5d) are presented and discussed.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Cyclometallated [C,N,O] Complexes as Metalloligands: Synthesis and Structural Characterisation of New Di‐, Tri‐, Tetra‐ and Pentanuclear Heterometallic Complexes
Authors: Gómez‐Blanco Nina , Fernández Jesús J. , Fernández Alberto , Vázquez‐García Digna , López‐Torres Margarita , Vila José M. 
Published: April 2009

AbstractReaction of the Schiff‐base ligands 4‐(4‐NC5H4)C6H4C(H)=N(C6H3OH‐2‐tBu‐5) (a) and (4‐NC5H4)C(H)=N(C6H3OH‐2‐tBu‐5) (b) with palladium(II) acetate in toluene at 60 °C gave the tetranuclear orthometallated palladium complexes 1a and 1b, respectively, as air‐stable solids. Treatment of 1a and 1b with triphenylphosphane gave the mononuclear species 2a and 2b upon splitting of the polynuclear structure. Reaction of 1a with the tertiary diphosphanes Ph2P(CH2)4PPh2 (dppb), Fe(C5H4PPh2)2 (dppf), Ph2PC(H)=C(H)PPh2 (t‐dppe) and Ph2P(CH2)6PPh2 (dpph), and 1b with dppb and dppf, in a 1:2 molar ratio gave complexes 3a–6a and 3b and 4b, respectively. Reaction of 2a, 4a and 6a with hexacarbonylchromium or ‐tungsten and 2b and 3b with hexacarbonylchromium, ‐molybdenum or ‐tungsten in thf under UV activation gave complexes 7a–12a and 5b–10b, respectively, which contain an M(CO)5 fragment coordinated to the pyridine nitrogen atom. Treatment of 2b with [RuCl2(CO)(dmf)(PPh3)2] in chloroform at room temperature for 2 d afforded 11b. Treatment of ligands (2‐NC5H4)C(H)=N(C6H4OH‐2) (c) and (2‐NC5H4)C(H)=N(C6H3OH‐2‐tBu‐5) (d) with palladium(II) acetate yielded the mononuclear palladium acetate complexes 1c and 1d, respectively. Treatment of 1c and 1d with aqueous sodium chloride, or, alternatively, treatment of c and d with K2[PdCl4], gave chloropalladium complexes 2c and 2d, respectively. Treatment of 2c and 2d with silver perchlorate and triphenylphosphane in acetone gave the mononuclear phosphane complexes 3c and 3d, respectively.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
How To Tune Acid‐Induced Ring Enlargement Reactions – The Strange Case of 2H‐Azaphosphirene Complexes and Its Surprising Dichotomy
Authors: Helten Holger , von Frantzius Gerd , Schnakenburg Gregor , Daniels Jörg , Streubel Rainer 
Published: April 2009

Abstract2H‐Azaphosphirene complex 1a reacted with TfOH, cyclohexyl isocyanide, and subsequently with NEt3 – P–N‐bond‐selectively – to give the first 2,3‐dihydro‐1,3‐azaphosphete complex 2. Under the same conditions, 2H‐azaphosphirene complex 1b underwent a P–C‐bond‐selective ring enlargement with phenylacetylene with formation of 2H‐1,2‐azaphosphole complex 3. Apart from X‐ray crystallographic data (2, 3), DFT calculations are discussed, which provide first insight into this surprising dichotomy.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
The Role of Amine–B(C6F5)3 Adducts in the Catalytic Reduction of Imines with H2: A Computational Study
Authors: Privalov Timofei 
Published: April 2009

AbstractThis study thoroughly examines the potential energy surfaces (PESs) of two possible mechanisms for reduction of imines by B(C6F5)3 and H2. The key reaction steps of the first catalytic mechanism, which is the focus of our study, are: (i) the uptake of H2 by a thermally activated amine–B(C6F5)3 species; (ii) proton transfer from the NH2+ moiety of [RNH2CH2R′]+[HB(C6F5)3]– to the imine; (iii) nucleophillic attack of the C‐center of the iminium ion by the BH– group. The potential energy barriers of the latter, as determined by calculating the evolution of the H‐bonded complex of an imine and [RNH2CH2R′]+[HB(C6F5)3]– in toluene, are around 10 kcal mol–1 each. In the second mechanism, only imines serve as basic partners of B(C6F5)3 in the H2 activation, which affords an [RN(H)CHR′]+[HB(C6F5)3]– ion pair; direct reduction then proceeds via nucleophilic attack of the C‐center by the BH– in [RN(H)CHR′]+[HB(C6F5)3]–. This route becomes catalytic when the product amine is released into the solvent and B(C6F5)3 is re‐used for H2 activation. Upon taking into account the association energy of an amine–B(C6F5)3 adduct [–9.5 kcal mol–1 for tBuN(H)CH2Ph and B(C6F5)3 in toluene], the potential energy barrier for H2 uptake by an imine and B(C6F5)3 increases to 14.5 kcal mol–1. We report a somewhat lower potential energy barrier for H2 uptake by thermally activated amine–B(C6F5)3 adducts [12.7 kcal mol–1 for the B‐N adduct of tBuN(H)CH2Ph and B(C6F5)3 in toluene], although the difference between the two H2 activationbarriers is within the expected error of the computational method. Two catalytic routes are compared based on B3LYP‐computed PESs in solvent (toluene).(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Shaping cooperation behavior: The role of accessibility experiences and uncertainty
Authors: Müller Patrick A. , Greifeneder Rainer , Stahlberg Dagmar , van den Bos Kees , Bless Herbert 
Published: April 2009

AbstractThe present research investigates the influence on cooperative behavior of accessibility experiences associated with the retrieval of fairness‐relevant information from memory. We argue that the decision whether to cooperate in negotiations depends not only on information about the appropriateness of the negotiation procedure, but also on the experience of how difficult or easy it is to come up with this information. Supporting this hypothesis, it is shown that in the context of a bargaining experiment, participants' experiences of ease or difficulty in retrieving unfair aspects of the respective negotiation procedure strongly influence their cooperation behavior. In addition, we hypothesize and empirically substantiate that the influence of accessibility experiences on cooperation behavior occurs particularly in situations of certainty salience. Implications for future research on cooperation and on accessibility experiences are discussed. Copyright © 2009 John Wiley & Sons, Ltd.
A boundary element method/Brownian dynamics approach for simulating DNA electrophoresis in electrically insulating microfabricated devices
Authors: Cho Jaeseol , Kenward Martin , Dorfman Kevin D. 
Published: April 2009

AbstractWe present an approach for merging boundary element method (BEM) solutions of the electric field in electrically insulating complex geometries with Brownian dynamics (BD) simulations of DNA electrophoresis therein. Although a rote application of the standard BEM algorithm proves inaccurate and prohibitively expensive, we show that regularization of the near‐wall electric field and an updating scheme commensurate with the characteristic length scale of the BD simulation furnishes a robust, efficient simulation protocol. The accuracy of the BEM‐BD method is verified by simulating λ‐DNA collisions with an isolated, insulating cylindrical obstacle and comparing the results with equivalent BD simulations that employ the exact solution for the electric field. The computational overhead of our implementation of BEM‐BD is comparable to an existing finite element method/BD approach. The BEM‐BD algorithm is readily parallelized and well‐suited to time‐dependent and responsive electric fields, making it broadly applicable to simulating DNA electrophoresis in microfluidic devices.
Sample stacking in CZE using dynamic thermal junctions I. Analytes with low dpKa/dT crossing a single thermally induced pH junction in a BGE with high dpH/dT
Authors: Mandaji Marcos , Rübensam Gabriel , Hoff Rodrigo Barcellos , Hillebrand Sandro , Carrilho Emanuel , Kist Tarso Ledur 
Published: April 2009

AbstractThe possibility to compress analyte bands at the beginning of CE runs has many advantages. Analytes at low concentration can be analyzed with high signal‐to‐noise ratios by using the so‐called sample stacking methods. Moreover, sample injections with very narrow initial band widths (small initial standard deviations) are sometimes useful, especially if high resolutions among the bands are required in the shortest run time. In the present work, a method of sample stacking is proposed and demonstrated. It is based on BGEs with high thermal sensitive pHs (high dpH/dT) and analytes with low dpKa/dT. High thermal sensitivity means that the working pKa of the BGE has a high dpKa/dT in modulus. For instance, Tris and Ethanolamine have dpH/dT=−0.028/°C and −0.029/°C, respectively, whereas carboxylic acids have low dpKa/dT values, i.e. in the −0.002/°C to+0.002/°C range. The action of cooling and heating sections along the capillary during the runs affects also the local viscosity, conductivity, and electric field strength. The effect of these variables on electrophoretic velocity and band compression is theoretically calculated using a simple model. Finally, this stacking method was demonstrated for amino acids derivatized with naphthalene‐2,3‐dicarboxaldehyde and fluorescamine using a temperature difference of 70°C between two neighbor sections and Tris as separation buffer. In this case, the BGE has a high pH thermal coefficient whereas the carboxylic groups of the analytes have low pKa thermal coefficients. The application of these dynamic thermal gradients increased peak height by a factor of two (and decreased the standard deviations of peaks by a factor of two) of aspartic acid and glutamic acid derivatized with naphthalene‐2,3‐dicarboxaldehyde and serine derivatized with fluorescamine. The effect of thermal compression of bands was not observed when runs were accomplished using phosphate buffer at pH 7 (negative control). Phosphate has a low dpH/dT in this pH range, similar to the dKa/dT of analytes. It is shown that ∣dKa/dT−dpH/dT∣≫0 is one determinant factor to have significant stacking produced by dynamic thermal junctions.
Differential unitary space‐time signal designs with improved performance using parametric equivalence
Authors: Smith David B. , Hanlen Leif W. 
Published: April 2009

AbstractWe present two unitary space‐time signal designs for two or more transmit antennas. The first design is a reparametrisation of rotation matrices applied to diagonal matrices to form unitary space‐time codes. The rotation matrices are applied as matrices similar to Alamouti‐style block codes. The second design subsumes rotation matrices applied to diagonal matrices for two antennas. These designs are applied in a non‐coherent/differential framework. Optimisation of constellations is performed using the union bound on block‐error probability, for which a new exact closed‐form expression is given. Both designs have superior block‐error performance over previous designs, and have similar performance to each other. Copyright © 2009 John Wiley & Sons, Ltd.
Turbulence in a three‐dimensional wall‐bounded shear flow
Authors: Holstad A. , Andersson H. I. , Pettersen B. 
Published: April 2009

AbstractA new turbulent flow with distinct three‐dimensional characteristics has been designed in order to study the impact of mean‐flow skewing on the turbulent coherent vortices and Reynolds‐averaged statistics. The skewing of a unidirectional plane Couette flow was achieved by means of a spanwise pressure gradient. Direct numerical simulations of the statistically steady Couette–Poiseuille flow enabled in‐depth explorations of the turbulence field in the skewed flow. The imposition of a modest spanwise gradient turned the mean flow about 8° away from the original Couette flow direction and this turning angle remained nearly the same over the entire cross section. Nevertheless, a substantial non‐alignment between the turbulent shear stress angle and the mean velocity gradient angle was observed. The structure parameter turned out to slightly exceed that in the pure Couette flow, contrary to the observations made in some other three‐dimensional shear flows.Coherent flow structures, which are known to be associated with the Reynolds shear stress in near‐wall regions, were identified by the λ2‐criterion. Instantaneous and ensemble‐averaged vortices resembled those found in the unidirectional Couette flow. In the skewed flow, however, the vortex structures were turned to align with the local mean‐flow direction. The conventional symmetry between Case 1 and Case 2 vortices was broken due to the mean‐flow three‐dimensionality. The turning of the coherent vortices and the accompanying symmetry‐breaking gave rise to secondary and tertiary turbulent shear stress components. By averaging the already ensemble‐averaged shear stresses associated with Case 1 and Case 2 vortices in the homogeneous directions, a direct link between the educed near‐wall structures and the Reynolds‐averaged turbulent stresses was established. These observations provide evidence in support of the hypothesis that the structural model proposed for two‐dimensional turbulent boundary layers remains valid also in flows with moderate mean three‐dimensionality. Copyright © 2009 John Wiley & Sons, Ltd.
Rolling over stock index futures contracts
Authors: Carchano Óscar , Pardo Ángel 
Published: April 2009

AbstractDerivative contracts have a finite life limited by their maturity. The construction of continuous series, however, is crucial for academic and trading purposes. In this study, we analyze the relevance of the choice of the rollover date, defined as the point in time when we switch from the front contract series to the next one. We have used five different methodologies in order to construct five different return series of stock index futures contracts. The results show that, regardless of the criterion applied, there are not significant differences between the resultant series. Therefore, the least complex method can be used in order to reach the same conclusions. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 28:684–694, 2009