bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simple analysis of wide annular slot antennas
Authors: Kucharski Andrzej A. 
Published: June 2006

AbstractA simple moment method solution to analyze so‐called annular slot antennas positioned at the interface between two homogeneous half‐spaces is given. The formulation takes into account radial magnetic currents and enables easy analysis of slots that are not necessarily narrow. The generalization into more challenging case of multilayered environment is straightforward. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1679–1683, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21802
Multiband antenna using a half‐wavelength loaded line structure for mobile handheld systems
Authors: Jung Byungwoon , Shin Hoo , Harackiewicz Frances J. , Park Myun‐Joo , Lee Byungje 
Published: June 2006

AbstractA novel multiband internal antenna is proposed, which can be applied for GSM(880–960 MHz), GPS(1575.42 MHz), DCS(1710–1880 MHz), PCS(1850–1990 MHz), and WCDMA(1920–2170 MHz) band mobile handheld systems, by using a half‐wavelength loaded line structure (HWLLS). The proposed antenna is a combined structure of HWLLS and a shorted monopole. A gap is cut between the antenna shorting pad and the PCB ground plane of system. Then this gap is connected by a chip inductor in order to easily control the upper frequency bands, DCS, PCS, and WCDMA without degradation of resonant characteristics in the lower bands, GSM and GPS. Simulation and experimental results show that the proposed antenna provides enough effective bandwidth (VSWR <2.5) to cover all five bands with the peak gain variation of less than 0.53 dB with varying the chip inductance of less than 3.3 nH. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1683–1687, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21803
Development of ultra wideband planar stepped‐fat dipole antenna
Authors: Park Young‐Jin , Song Jong‐Hwa 
Published: June 2006

AbstractAn ultra wideband (UWB) planar stepped‐fat dipole antenna is developed. The antenna consists of two stepped‐fat arms used for improving the bandwidth of a fat dipole antenna using only two square arms. A prototype antenna is designed and fabricated for high‐resolution UWB image radars. For verification of the performance, reflection coefficient and radiation patterns are measured. Also, the impulse response of the antenna is obtained. It is shown that return loss of the antenna between 0.5 and 2.7 GHz is better than 10 dB. From the impulse response, ringing and dispersion are observed. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1698–1701, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21806
Micromachined interdigital filter on silicon
Authors: Thomson Neil , Hong Jia‐Sheng 
Published: June 2006

AbstractThis article presents a microwave interdigital filter manufactured on high resistive silicon substrate. Two filter designs are referenced in this article; both filters are five pole interdigital filters with one using uniform impedance resonators and the other using stepped impedance resonators. The fabrication of the filters on silicon has been possible with the use of micromachining. This therefore enables filters to be manufactured with smaller footprints and gives rise to further development with micro‐electro‐mechanical systems technology. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1862–1866, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21810
Substituent effects on 15N and 13C NMR chemical shifts of 3‐phenylisoxazoles: a theoretical and spectroscopic study
Authors: Schofield Mark H. , Sorel Marie‐Adele , Manalansan Ryan J. , Richardson David P. , Markgraf J. Hodge 
Published: June 2006

AbstractThe synthesis and assignment of 15N and 13C NMR signals of the isoxazole ring in a series of para‐substituted 3‐phenyl derivatives are reported. DFT calculations of 15N and 13C chemical shifts are presented and compared to observed values. Substituent effects are interpreted in terms of the Hammett correlation and calculated bond orders. Copyright © 2006 John Wiley & Sons, Ltd.
Hexose‐specificity of hexokinase and ADP‐dependence of pyruvate kinase play important roles in the control of monosaccharide utilization in freshly diluted boar spermatozoa
Authors: Medrano Antonio , García‐Gil Núria , Ramió Laura , Montserrat Rivera Ma. , Fernández‐Novell Josep Ma. , Ramírez Alfredo , Peña Alejandro , Dolors Briz Ma. , Pinart Elisabet , Concha Ilona I. , Bonet Sergi , Rigau Teresa , Rodríguez‐Gil Joan E. 
Published: June 2006

AbstractIncubation of boar sperm from fresh ejaculates in a minimal medium with 10 mM glucose induced a fast and intense activation of glycolysis, as indicated by the observed increases in the intracellular levels of glucose 6‐phosphate (G 6‐P) and ATP and the rate of formation of extracellular L‐lactate. The effect of glucose was much more intense than that induced by fructose, sorbitol, and mannose. The greater utilization of glucose was related to a much greater sensitivity to hexokinase when compared with the other monosaccharides. Thus, the presence of 0.5 mM glucose induced total hexokinase activity in supernatants from sperm extracts of 1.7 ± 0.1 mIU/mg protein, while the same concentration of both fructose, mannose, and sorbitol induced total hexokinase activity from 0.3 ± 0.1 mIU/mg protein to 0.60 ± 1 mIU/mg protein. Kinetic analysis of the total pyruvate kinase activity indicated that this activity was greatly dependent on the presence of ADP and also showed a great affinity for PEP, with an estimated Km in supernatants of 0.15–0.20 mM. Immunological location of proteins closely related to glycolysis, like GLUT‐3 hexose transporter and hexokinase‐I, indicated that these proteins showed the trend to be distributed around or in the cellular membranes of both head and midpiece in a grouped manner. We conclude that glycolysis is regulated by both the specific availability of a concrete sugar and the internal equilibrium between ATP and ADP levels. Furthermore, localization of proteins involved in the control of monosaccharide uptake and phosphorylation suggests that glycolysis starts at concrete points in the boar‐sperm surface. Mol. Reprod. Dev. 1179–1194, 2006. © 2006 Wiley‐Liss, Inc.
A potential role for triglyceride as an energy source during bovine oocyte maturation and early embryo development
Authors: Ferguson Elizabeth M. , Leese Henry J. 
Published: June 2006

AbstractThe potential role of endogenous triglyceride in bovine oocyte maturation and preimplantation development has been investigated. Bovine immature oocytes were recovered from abattoir‐derived ovaries, matured and fertilised in vitro and the zygotes grown to the blastocyst stage in SOFaaBSA. Methyl palmoxirate (MP) blocks the oxidation of fatty acids by inhibiting mitochondrial carnitine palmitoyltransferase A. The development of zygotes exposed to MP during oocyte maturation, and of zygotes exposed to MP during embryo culture has been assessed in terms of oxygen consumption by oocytes and embryos during a 4–6 hr incubation period in the presence of MP and as blastocyst formation and cell number. Immature oocytes exposed to MP during maturation had reduced capacity to form blastocysts after fertilisation; the same effect was apparent, but to a lesser extent, in zygotes exposed to MP during embryo development. Oxygen consumption values of oocytes and blastocysts in the absence of exogenous substrates were similar to those in control medium containing nutrients. MP‐inhibited oxygen consumption of immature oocytes, mature oocytes, cleavage stages embryos and blastocysts by 64, 45, 12 and 13%, respectively. The data are consistent with a role for triglyceride as a key energy source during bovine oocyte maturation and potentially, during preimplantation embryo development. Mol. Reprod. Dev. 1195–1201, 2006. © 2006 Wiley‐Liss, Inc.
Suppression of endogenous estrogen during development affects porcine epididymal sperm maturation
Authors: McCarthy Megan J. , At‐Taras Eeman E. , Pearl Christopher A. , Nitta‐Oda Barbara S. , Roser Janet F. , Conley Alan J. , Berger Trish 
Published: June 2006

AbstractEstrogen plays an important role in male reproduction, critical for sustained fertility in some species. Reducing estrogen's interaction with its receptor(s) in monkey and mouse models is associated with reduced sperm motility and, in some cases, documented elimination of sperm fertilizing ability, suggesting that normal epididymal function may be estrogen dependent. The objective of these experiments was to evaluate the effects of reduced endogenous estrogen on development of epididymal function in the pig, a species in which males have very high levels of endogenous estrogen. Letrozole, a potent inhibitor of estrogen synthesis, was administered to neonatal boars from 1 week of age and markedly suppressed estrogen production. Epididymal function assessed as acquisition of sperm fertilizing ability (in vitro fertilization of zona‐free oocytes) was reduced in Letrozole‐treated animals at 24 and 28 weeks of age (23% and 30% fertilization, respectively compared with 37% and 54% in vehicle controls) but had recovered by 32 weeks of age. Cauda epididymal sperm numbers were reduced in treated animals (35% of control values at 20 weeks of age) but appeared to be recovering at 32 weeks of age. Reduction of endogenous estrogen had no effect on other aspects of epididymal function (percentage of motile sperm, sperm motion parameters, sperm head morphometrics, or ability of sperm to undergo an acrosome reaction). Reducing endogenous estrogen during postnatal development appears to have transient effects on porcine epididymal function. These transient effects suggest that the pig, with its high endogenous estrogen, may respond differently than other species to reduced estrogen synthesis. Mol. Reprod. Dev. 1122–1128, 2006. © 2006 Wiley‐Liss, Inc.
Expression of genes associated with allantois emergence in ovine and bovine conceptuses
Authors: Ledgard A.M. , Lee R.S‐F. , Peterson A.J. 
Published: June 2006

AbstractIn the development of ruminant embryos, the emergence and growth of the allantois is critical for the establishment of the chorioallantoic placenta. The allantoic membrane contributes to all the vasculature that perfuses the placental tissues and the fetal membranes. Using suppressive subtractive hybridization to compare mRNA from Day 13 ovine preimplantation conceptuses (prior to allantoic emergence) with Day 17 allantoic membrane, we identified nine genes whose expression was associated with the emergence of the allantoic sac. Collagen alpha 1 type XII, collagen alpha 2 type I, collagen alpha 2 type V, epsilon 4 beta‐globin, osteonectin, and uroplakin were expressed at significantly greater levels in ovine Day 17 allantois compared to Day 13 conceptuses. These genes are associated with the extracellular matrix and most likely are involved in establishing and strengthening the structural integrity of the allantoic sac and in the development of the blood vessels. RalB expression increased with development although at significantly greater levels in the allantois only at Day 19. Hoxa‐10 and RhoA showed no differential expression during this period. All these genes showed a similar temporal pattern of expression in bovine conceptuses at equivalent stages of development with significantly greater expression of all these genes, except for Hoxa‐10, found in Day 24 allantois compared to Day 14 conceptuses. This suggests that the role they play in allantoic emergence, growth and function is conserved in both ruminant species and that their expression is regulated in a similar manner. The interactions and regulation of this process remains to be fully explained. Mol. Reprod. Dev. 1084–1093, 2006. © 2006 Wiley‐Liss, Inc.
Partial field‐of‐view spiral phase‐contrast imaging using complex difference processing
Authors: Nezafat Reza , Thompson Richard B. , Derbyshire J. Andrew , McVeigh Elliot R. 
Published: June 2006

AbstractRapid flow imaging was achieved with a partial field of view (pFOV) spiral motion‐encoded technique. The FOV and the acquisition time were reduced by a factor of 2 by undersampling k‐space. The pFOV spiral k‐space trajectory aliased signals from outside a circular ring whose radius was inversely proportional to the distance between adjacent spirals in k‐space. In this study the FOV was adjusted so that all of the moving spins were located inside the inner half circle of the full FOV. Complex subtraction of two differentially flow‐encoded images was used to remove the spurious phase sources and provide an accurate measurement of flow. The complex subtraction process also serves to eliminate aliasing artifacts that are generated by static tissue from outside the reduced FOV. Experiments in a flow phantom and volunteers showed that the flow estimates obtained by pFOV spiral motion encoding are in good agreement with the estimates reconstructed using complex difference processing. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Effect of the potassium channel opener WAY‐133537 on the overactive bladder of spinalized rats
Authors: Elzayat Ehab , Khaled Sabri , Kashiwabara Takeshi , Elhilali Mostafa , Corcos Jacques 
Published: June 2006

AbstractAimsTo test the efficacy of WAY‐133537 for the treatment of overactive bladder (OAB) in a chronic paraplegic rat model.Materials and MethodsForty‐eight female Sprague–Dawley rats were used in this study. Six animals served as normal controls (without spinal cord transaction (ST)), while 42 rats underwent ST at the 10th thoracic vertebra. Two weeks after ST, cystometrogram (CMG) was performed in six randomly chosen animals to ensure the development of neurogenic detrusor overactivity. The remaining 36 rats were divided into three equal groups, 12 received the vehicle as “paraplegic controls,” 12 received WAY‐133537 0.3 mg/kg, and 12 received WAY‐133537 3 mg/kg. Each “paraplegic control” and treatment group was further divided into two sub‐groups (n = 6), with CMG at 3 and 4 weeks after ST, respectively.ResultsTwo weeks after ST, all “vehicle control” rats developed detrusor overactivity with a mean frequency of 0.96 and 1.48 contractions/min and amplitude of 22.96 and 31.22 cm H2O with 1‐ and 2‐week treatment, respectively. Neurogenic detrusor overactivity disappeared from 50% of rats that received WAY‐133537 0.3 mg/kg for 1 week, and frequency decreased to 0.41 contractions/min. After 2 weeks of treatment, detrusor overactivity vanished from 67% of the animals with even further reduction in the frequency of detrusor overactivity (0.22 contractions/min,P < 0.01). In rats that received 3 mg/kg of the drug for 1 week, detrusor overactivity disappeared from only one animal with a non‐significant decline in frequency. Fifty percent of rats given WAY‐133537 at the dose of 3 mg/kg/day for 2 weeks manifested no detrusor overactivity.ConclusionsWAY‐133537 shows efficacy in increasing bladder capacity and reducing the frequency of spontaneous bladder contractions after ST in rats without decreasing voiding pressure. Neurourol. Urodynam. 25:808–814, 2006. © 2006 Wiley‐Liss, Inc.
State‐space partition techniques for multiterminal flows in stochastic networks
Authors: Daly Matthew S. , Alexopoulos Christos 
Published: June 2006

AbstractThis article develops state‐space partition methods for computing performance measures for stochastic networks with demands between multiple pairs of nodes. The chief concern is the evaluation of the probability that there exist separate, noninteracting flows that satisfy all demands. This relates to the multiterminal maximum flow problem discussed in the classic article of Gomory and Hu. The network arcs are assumed to have independent, discrete random capacities. We refer to the probability that all demands can be satisfied as the network reliability (with the understanding that its definition is application dependent). In addition, we also consider the calculation of secondary measures, such as the probability that a particular subset of demands can be met, and the probability that a particular arc lies on a minimum cut. The evaluation of each of these probabilities is shown to be NP‐hard. The proposed methods are based on an iterative partition of the system state space, with each iteration tightening the bounds on the measure of interest. This last property allows the design of increasingly efficient Monte Carlo sampling plans that yield substantially more precise estimators than the standard Monte Carlo method that draws samples from the original capacity distribution. © 2006 Wiley Periodicals, Inc. NETWORKS, Vol. 48(2), 90–111 2006
Studies on Jacobi–Davidson, Rayleigh quotient iteration, inverse iteration generalized Davidson and Newton updates
Authors: Zhou Yunkai 
Published: June 2006

AbstractWe study Davidson‐type subspace eigensolvers. Correction equations of Jacobi–Davidson and several other schemes are reviewed. New correction equations are derived. A general correction equation is constructed, existing correction equations may be considered as special cases of this general equation. The main theme of this study is to identify the essential common ingredient that leads to the efficiency of a diverse form of Davidson‐type methods. We emphasize the importance of the approximate Rayleigh‐quotient‐iteration direction. Copyright © 2006 John Wiley & Sons, Ltd.
Films of chitosan and N‐carboxymethylchitosan. Part II: effect of plasticizers on their physiochemical properties
Authors: Lamim Roberta , de Freitas Rilton Alves , Rudek Elimar Ivan , Wilhelm Helena Maria , Cavalcanti Osvaldo Albuquerque , Bresolin Tania Mari Bellé 
Published: June 2006

AbstractChitosan (Ch) and N‐carboxymethylchitosan (N‐CMCh) films were prepared by the casting method at concentrations of 1% and 2% of polymer, with or without plasticizer: polyethylene glycol (PEG‐400) and glycerol (G), at 15% (w/w). The influence of composition on mechanical properties, water vapour transmission rate (WVTR), water saturation, and aqueous dissolution of the films was analysed. The thermal stability of the mixture (polymer:plasticizer, 1:1) was evaluated by thermogravimetric analysis (TGA). In general, all the properties were affected by the plasticizers. The plasticized films showed lower strength and a higher percentage of elongation (%E), in the following order: G > PEG‐400 > unplasticized film. The total WVTR increased with Ch concentration, with a different WVTR profile for Ch and N‐CMCh. While the PEG‐400 addition did not significantly modify the WVTR profile of films, the glycerol enhanced the transport of water vapour through both polymers. The plasticizer addition increased the time of water film saturation, in the following order: G > PEG‐400 > unplasticized film; this was more pronounced in the N‐CMCh films, probably due to the formation of hydrogen bonds. The solubility of the films was also affected by their composition. Copyright © 2006 Society of Chemical Industry
Preparation and properties of ternary polyimide/SiO2/polydiphenylsiloxane composite films
Authors: Shang Zhenping , Lü Changli , Gao Lianxun 
Published: June 2006

AbstractA series of novel ternary polyimide/SiO2/polydiphenylsiloxane (PI/SiO2/PDPhS) composite films were prepared through co‐hydrolysis and condensation between tetramethoxysilane, diphenyldimethoxysilane (DDS) and aminopropyltriethoxysilane‐terminated polyamic acid, using an in situ sol–gel method. The composite films exhibited good optical transparency up to 30 wt% of total content of DDS and SiO2. SEM analysis showed that the PDPhS and SiO2 were well dispersed in the PI matrix without macroscopic separation of the composite films. TGA analysis indicated that the introduction of SiO2 could improve the thermal stability of the composite films. Dynamic mechanical thermal analysis showed that the composite films with low DDS content (5 wt%) had a higher glass transition temperature (Tg) than pure PI matrix. When the content of DDS was above 10 wt%, the Tg of the composite decreased slightly due to the plasticizing effect of flexible PDPhS linkages on the rigid PI chains. The composite films with high SiO2 content exhibited higher values of storage modulus. Tensile measurements also showed that the modulus and tensile strength of the composite films increased with increasing SiO2 content, and the composite films still retained a high elongation at break due the introduction of DDS. The density and water absorption of the composite films were also characterized. Copyright © 2006 Society of Chemical Industry
Effect of side‐chain length of succinic anhydride on coefficient of thermal expansion behavior of epoxy resins
Authors: Jin Fan‐Long , Han Mijeong , Park Soo‐Jin 
Published: June 2006

AbstractThe effect of an alkenyl side‐chain of succinic anhydride (SA) on the thermal behavior and the coefficient of thermal expansion (CTE) of diglycidylether of bisphenol A (DGEBA) epoxy resins was studied. The number of carbons in the side‐chain of SA was varied from 6 to 14 and N,N‐Dimethylbenzylamine was used as an accelerator. As a result, the reactivity of SA with epoxide groups was decreased on increasing the length of the alkenyl side‐chain of SA. The thermal stabilities of cured DGEBA/SA samples were approximately constant with varying alkenyl side‐chain of SA. Also, the CTE of the systems was increased as the length of the alkenyl side‐chain of SA increased. This could be attributed to the increased motion of the chain segments in the epoxy network structure induced by the longer alkenyl side‐chain of SA. The effect of amount anhydride, thermoplastics, and fillers on the CTE of the epoxy resins was also discussed. Copyright © 2006 Society of Chemical Industry
Solitonen im Bose‐Einstein‐Kondensat: Nichtlineare Materiewellenoptik
Authors: Eiermann Bernd , Oberthaler Markus 
Published: June 2006

AbstractBose‐Einstein‐Kondensate sind perfekte Quantensysteme für das Studium der Dynamik von Wellenpaketen. Ein mächtiges Werkzeug sind dabei periodische optische Potentiale aus Laserlicht. Ein solches optisches Gitter wirkt auf das Wellenpaket aus ultrakalten Atomen wie ein atomares Kristallgitter auf freie Elektronen. Dadurch entstehen Energiebänder. Weil die Potentialtiefe des optischen Gitters frei einstellbar ist, wird so die effektive Masse der Wellenpakete elegant steuerbar. Sogar eine negative effektive Masse ist im optischen Gitter realisierbar. Mit ihr lässt sich das Zerfließen eines Wellenpakets zeitlich umkehren. Das System ermöglicht auch die Erzeugung heller Solitonen, also nichtzerfließender Wellenpakete, obwohl sich die Atome untereinander abstoßen. Bislang wurden diese aus Wolken mit etwa 350 Rubidium‐Atomen erzeugt.
Möglichst keine Wellen schlagen. Physik des Schwimmens
Authors: Thaller Sigrid , Mathelitsch Leopold 
Published: June 2006

AbstractDie durchschnittliche Dichte des menschlichen Körpers weicht kaum von der des Wassers ab. Deshalb kann der Mensch schwimmen und auch tauchen. Wettkampfschwimmer nutzen den Auftrieb und den Wasserwiderstand optimal aus, um möglichst hohe Geschwindigkeiten zu erreichen. Die Energiebereitstellung im Körper spielt dabei eine wesentliche Rolle.
Tanz supermassereicher Schwarzer Löcher
Authors: Reiprich Thomas , Hudson Daniel 
Published: June 2006

AbstractVermutlich befindet sich im Zentrum fast jeder Galaxie ein supermassereiches Schwarzes Loch. Wenn Galaxien miteinander verschmelzen, sollten dies deshalb auch die Schwarzen Löcher tun. Mit Beobachtungen des Röntgen‐Weltraumteleskops Chandra ist es einem deutsch‐amerikanischen Astronomenteam nun gelungen, zwei supermassereiche Schwarze Löcher als gebundenes Paar zu identifizieren. Dieses steht am Beginn eines langsamen Verschmelzungsprozesses.