bluuebunny/crossref_metadata_2025 huggingface dataset:
The WASP project in the era of robotic telescope networks
Authors: Christian D. J. , Pollacco D. L. , Skillen I. , Irwin J. , Clarkson W. I. , Collier Cameron A. , Evans N. , Fitzsimmons A. , Haswell C. A. , Hellier C. , Hodgkin S. T. , Horne K. , Kane S. R. , Keenan F. P. , Lister T. A. , Norton A. J. , Osborne J. , Ryans R. , Street R. A. , West R. G. , Wheatley P. J.
Published: August 2006

We present the current status of the WASP project, a pair of wide angle photometric telescopes, individually called Super‐WASP. SuperWASP‐I is located in La Palma, and SuperWASP‐II at Sutherland in South Africa. SW‐I began operations in April 2004. SW‐II is expected to be operational in early 2006. Each SuperWASP instrument consists of up to 8 individual cameras using ultra‐wide field lenses backed by high‐quality passively cooled CCDs. Each camera covers 7.8 × 7.8 sq degrees of sky, for nearly 500 sq degrees of total sky coverage. One of the current aims of the WASP project is the search for extra‐solar planet transits with a focus on brighter stars in the magnitude range ∼8 to 13. Additionally, WASP will search for optical transients, track Near‐Earth Objects, and study many types of variable stars and extragalactic objects. The collaboration has developed a custom‐built reduction pipeline that achieves better than 1 percent photometric precision. We discuss future goals, which include: nightly on‐mountain reductions that could be used to automatically drive alerts via a small robotic telescope network, and possible roles of the WASP telescopes as providers in such a network. Additional technical details of the telescopes, data reduction, and consortium members and institutions can be found on the web site at: http://www.superwasp.org/. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Piloting a network of small telescopes
Authors: Fadavi M. , Verveer A. , Aymon J. , Merlin D. , Situ K. , Pennypackker C. , Biggs J. D. , White G. , Gould A. , Greenberg G. , Hoette V. , McCarron K. , Archer K. , Pino F. , Hibbs M. , Ford M. , Wetsch J.
Published: August 2006

The Pilot Small Telescope Network (PSTN) is a state‐of the art system of easily replicable and scalable hardware, software, servers, eXtensible Markup Language (XML) protocols, and network middleware connecting and developing a pilot array of robotic telescopes to one another and the user community. The PSTN is a developmental project that will allow growing access to these telescopes, and make available data to faculty, students and others in an environment of collaboration. The underlying goal of the PSTN is to broaden the quantity and quality of astronomical education and research, particularly with a focus on traditionally underserved populations. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
TAOS – The Taiwanese‐American Occultation Survey
Authors: Lehner M. J. , Alcock C. , Axelrod T. , Bianco F. , Byun Y.‐I. , Chen W.‐P. , Cook K. H. , Dave R. , de Pater I. , Giammarco J. , King S.‐K. , Lee T. , Lissauer J. , Marshall S. L. , Mondal S. , Nihei T. , Rice J. , Schwamb M. , Wang A. , Wang S.‐Y. , Wen C.‐Y. , Zhang Z.‐W.
Published: August 2006

The Taiwanese‐American Occultation Survey (TAOS) seeks to determine the number and size spectrum for small (∼3 km) bodies in the Kuiper Belt. This will be accomplished by searching for the brief occultations of bright stars (R ∼ 14) by these objects. We have designed and built a special purpose photometric monitoring system for this purpose. TAOS comprises four 50 cm telescopes, each equipped with a 2048 × 2048 pixel CCD camera, in a compact array located in the central highlands of Taiwan. TAOS will monitor up to 2 000 stars at 5 Hz. The system went into scientific operation in the autumn of 2005. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High level interfaces to the Robonet‐1.0 Homogeneous Telescope Network
Authors: Mottram C.
Published: August 2006

We describe the current high level interfaces used for communicating with the Robonet‐1.0 Homogeneous Telescope Network. This is a network of three telescopes, the Liverpool Telescope and the Faulkes Telescopes (North and South). We describe our use of RTML and web‐services to enable control of the network by intelligent agents. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
When the means justify the ends: effects of observability on the procedural fairness and distributive fairness of resource allocations
Authors: Hamilton Rebecca W.
Published: August 2006

While there is substantial research examining how recipients react to allocations that vary in procedural fairness (Colquitt, Conlon, Wesson, Porter, & Ng, 2001), previous research has not examined how those dividing resources among themselves and others manipulate procedural fairness (Tyler & Smith, 1998). In this paper, we introduce a measure that allows us to compare procedural fairness across resource allocations, and we use an experimental procedure in which participants vary the procedural fairness of their allocations. In three studies, we show that those dividing resources make proactive tradeoffs between distributive and procedural fairness. Participants increased the procedural fairness of their allocations when they knew recipients would observe their procedures, but they were less likely to divide the resources equally among recipients. The decreased emphasis on distributive fairness when procedures were observable resulted in higher joint outcomes, suggesting that the observability of procedures has important implications for the efficiency of resource allocation in groups. Copyright © 2006 John Wiley & Sons, Ltd.
The influence of the molecular structure of lipid membranes on the electric field distribution and energy absorption
Authors: Simeonova Margarita , Gimsa Jan
Published: August 2006

We consider the influence of the molecular structure of phospholipid membranes on their dielectric properties in the radio frequency range. Membranes have a stratified dielectric structure on the submolecular level, with the lipid chains forming a central hydrophobic layer enclosed by the polar headgroups (HGs) and bound water layers. In our numerical model, isotropic permittivities of 2.2 and 48.8 were assigned to the lipid chain and bound water layers, respectively. The HG region was assumed to possess an anisotropic static permittivity with 142.2 and 30.2 in the tangential and normal directions, respectively. The permittivities of the HG and bound water regions have been assumed to disperse at frequencies around 51 and 345 MHz to become 2.2 and 1.8, respectively, in both the normal and tangential directions. Electric field distribution and absorption were calculated for phospholipid vesicles with 75 nm radius as an example. Significant absorption has been obtained in the HG and bound water regions. Averaging the membrane absorption over the layers resulted in a decreased absorption below 1 GHz but a more than 10‐fold increase above 1 GHz, compared to a model with a homogeneous membrane of averaged properties. We propose single particle dielectric spectroscopy by AC electrokinetics at low‐bulk medium conductivities for an experimental verification of our model. Bioelectromagnetics 27:652–666, 2006. © 2006 Wiley‐Liss, Inc.
Adjuvant radiotherapy for rectal cancer
Authors: Moesta K T , Köckerling F
Published: August 2006

A hotly debated issue
A Tale of Two Targets: Differential RNA Selectivity of Nucleobase–Aminoglycoside Conjugates
Authors: Blount Kenneth F. , Tor Yitzhak
Published: August 2006

Aminoglycoside antibiotics are RNA‐binding polyamines that can bind with similar affinities to structurally diverse RNA targets. To design new semisynthetic aminoglycosides with improved target selectivity, it is important to understand the energetic and structural basis by which diverse RNA targets recognize similar ligands. It is also imperative to discover how novel aminoglycosides could be rationally designed to have enhanced selectivity for a given target. Two RNA drug targets, the prokaryotic ribosomal A‐site and the HIV‐1 TAR, provide an excellent model system in which to dissect the issue of target selectivity, in that they each have distinctive interactions with aminoglycosides. We report herein the design, synthesis, and binding activity of novel nucleobase–aminoglycoside conjugates that were engineered to be more selective for the A‐site binding pocket. Contrary to the structural design, the conjugates bind the A‐site more weakly than does the parent compound and bind the TAR more tightly than the parent compound. This result implies that the two RNA targets differ in their ability to adapt to structurally diverse ligands and thus have inherently different selectivities. This work emphasizes the importance of considering the inherent selectivity traits of the RNA target when engineering new ligands.
“Click Peptides”—Chemical Biology‐Oriented Synthesis of Alzheimer's Disease‐Related Amyloid β Peptide (Aβ) Analogues Based on the “O‐Acyl Isopeptide Method”
Authors: Sohma Youhei , Kiso Yoshiaki
Published: August 2006

A clear understanding of the pathological mechanism of amyloid β peptide (Aβ) 1–42, a currently unexplained process, would be of great significance for the discovery of novel drug targets for Alzheimer's disease (AD) therapy. To date, though, the elucidation of these Aβ1–42 dynamic events has been a difficult issue because of uncontrolled polymerization, which also poses a significant obstacle in establishing experimental systems with which to clarify the pathological function of Aβ1–42. We have recently developed chemical biology‐oriented pH‐ or phototriggered “click peptide” isoform precursors of Aβ1–42, based on the “O‐acyl isopeptide method”, in which a native amide bond at a hydroxyamino acid residue, such as Ser, is isomerized to an ester bond, the target peptide subsequently being generated by an O–N intramolecular acyl migration reaction. These click peptide precursors did not exhibit any self‐assembling character under physiological conditions, thanks to the presence of the one single ester bond, and were able to undergo migration to give the target Aβ1–42 in a quick and easy, one‐way (so‐called “click”)conversion reaction. The use of click peptides could be a useful strategy to investigate the biological functions of Aβ1–42 in AD through inducible activation of Aβ1–42 self‐assembly.
Cyclic Control of the Surface Properties of a Monolayer‐Functionalized Electrode by the Electrochemical Generation of Hg Nanoclusters
Authors: Riskin Michael , Basnar Bernhard , Katz Eugenii , Willner Itamar
Published: August 2006

Hg2+ ions are bound to a 1,4‐benzenedimethanethiol (BDMT) monolayer assembled on a Au electrode. Electrochemical reduction of the Hg2+–BDMT monolayer to Hg+–BDMT (at E°=0.48 V) and subsequently to Hg0–BDMT (at E°=0.2 V) proceeds with electron‐transfer rate constants of 8 and 11 s−1, respectively. The Hg0 atoms cluster into aggregates that exhibit dimensions of 30 nm to 2 μm, within a time interval of minutes. Electrochemical oxidation of the nanoclusters to Hg+ and further oxidation to Hg2+ ions proceeds with electron‐transfer rate constants corresponding to 9 and 43 s−1, respectively, and the redistribution of Hg2+ on the thiolated monolayer occurs within approximately 15 s. The reduction of the Hg2+ ions to the Hg0 nanoclusters and their reverse electrochemical oxidation proceed without the dissolution of mercury species to the electrolyte, implying high affinities of Hg2+, Hg+, and Hg0 to the thiolated monolayer. The electrochemical transformation of the Hg2+‐thiolated monolayer to the Hg0‐nanocluster‐functionalized monolayer is characterized by electrochemical means, surface plasmon resonance (SPR), X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact‐angle measurements. The Hg0‐nanocluster‐modified surface reveals enhanced hydrophobicity (contact angle 76°) as compared to the Hg2+‐thiolated monolayer (contact angle 57°). The hydrophobic properties of the Hg0‐nanocluster‐modified electrode are further supported by force measurements employing a hydrophobically modified AFM tip.
Chemical Synthesis of a Glycolipid Library by a Solid‐Phase Strategy Allows Elucidation of the Structural Specificity of Immunostimulation by Rhamnolipids
Authors: Bauer Jörg , Brandenburg Klaus , Zähringer Ulrich , Rademann Jörg
Published: August 2006

The first synthesis of a glycolipid library by hydrophobically assisted switching phase (HASP) synthesis is described. HASP synthesis enables flexible switching between solution‐phase steps and solid‐supported reactions conducted with molecules attached to a hydrophobic silica support. A library of glycolipids derived from the lead compound 1—a strongly immunostimulatory rhamnolipid—with variations in the carbohydrate part, the lipid components, and the stereochemistry of the 3‐hydroxy fatty acids was designed and synthesized. The enantioselective synthesis of the 3‐hydroxy fatty acid building blocks was achieved by employing asymmetric hydrogenation of 3‐oxo fatty acids. Glycolipids were prepared by this approach without any intermediary isolation steps, mostly in excellent yields. Final deprotection to the carboxylic acids was accomplished by enzymatic ester cleavage. All prepared rhamnolipids were tested for their immunostimulatory properties against human monocyte cells by assaying the secretion of the cytokine tumor necrosis factor α (TNFα) into the medium. The observed structure–activity relationships of rhamnolipids indicate a specific, recognition‐based mode of action, with small structural variations in the rhamnolipids resulting in strong effects on the immunostimulatory activities of the rhamnolipids at low micromolar concentrations.
Efficient kinetic resolution of (R,S)‐1‐trimethylsilylethanol via lipase‐mediated enantioselective acylation in ionic liquids
Authors: Lou Wen‐Yong , Zong Min‐Hua
Published: August 2006

Efficient enantioselective acylation of (R,S)‐1‐trimethylsilylethanol {(R,S)‐1‐TMSE} with vinyl acetate catalyzed by immobilized lipase from Candida antarctica B (i.e., Novozym 435) was successfully conducted in ionic liquids (ILs). A remarkable enhancement in the initial rate and the enantioselectivity of the acylation was observed by using ILs as the reaction media when compared to the organic solvents tested. Also, the activity, enantioselectivity, and thermostability of Novozym 435 increased with increasing hydrophobicity of ILs. Of the six ILs examined, the IL C4MIm·PF6 gave the fastest initial rate and the highest enantioselectivity, and was consequently chosen as the favorable medium for the reaction. The optimal molar ratio of vinyl acetate to (R,S)‐1‐TMSE, water activity, and reaction temperature range were 4:1, 0.75, and 40 –50°C, respectively, under which the initial rate and the enantioselectivity (E value) were 27.6 mM/h and 149, respectively. After a reaction time of 6 h, the ee of the remaining (S)‐1‐TMSE reached 97.1% at the substrate conversion of 50.7%. Additionally, Novozym 435 was effectively recycled and reused in C4MIm·PF6 for five consecutive runs without substantial lose in activity and enantioselectivity. The preparative scale kinetic resolution of (R,S)‐1‐TMSE in C4MIm·PF6 is shown to be very promising and useful for the industrial production of enantiopure (S)‐1‐TMSE. Chirality 2006. © 2006 Wiley‐Liss, Inc.
Enantioselective separation and online affinity chromatographic characterization of R,R‐ and S,S‐fenoterol
Authors: Beigi Farideh , Bertucci Carlo , Zhu Weizhong , Chakir Khalid , Wainer Irving W. , Xiao Rui‐Ping , Abernethy Darrell R.
Published: August 2006

Background: rac‐Fenoterol is a β2‐adrenoceptor agonist (β2‐AR) used in the treatment of asthma. It has two chiral centers and is marketed as a racemic mixture of R,R′‐ and S,S′‐fenoterol (R‐F and S‐F). Here we report the separation of the R‐F and S‐F enantiomers and the evaluation of their binding to and activation of the β2‐AR. Methods: R‐F and S‐F were separated from the enantiomeric mixture by chiral chromatography and absolute configuration determined by circular dichroism. β2‐AR binding was evaluated using frontal affinity chromatography with a stationary phase containing immobilized membranes from HEK‐293 cells that express human β2‐AR and standard membrane binding studies using the same membranes. The effect of R‐F and S‐F on cardiomyocyte contractility was also investigated using freshly isolated adult rat cardiomyocytes. Results: Chiral chromatography of rac‐fenoterol yielded separated peaks with an enantioselectivity factor of 1.21. The less retained peak was assigned the absolute configuration of S‐F and the more retained peak R‐F. Frontal chromatography using membrane‐bound β2‐AR as the stationary phase and rac‐3H‐fenoterol as a marker ligand showed that addition of increasing concentrations of R‐F to the mobile phase produced concentration‐dependent decreases in rac‐3H‐fenoterol retention, while similar addition of S‐F produced no change in rac‐3H‐fenoterol retention. The calculated dissociation constant of R‐F was 472 nM and the number of available binding sites 176 pmol/column, which was consistent with the results from the membrane binding study 460 ± 55 nM (R‐F) and 109,000 ± 10,400 nM (S‐F). In the cardiomyocytes, R‐F increased maximum contractile response from (265 ± 11.6)% to (306 ± 11.8)% of resting cell length (P < 0.05) and reduced EC50 from −7.0 ± 0.270 to −7.1 ± 0.2 log[M] (P < 0.05), while S‐F had no significant effect. Discussion: Previous studies have shown that rac‐fenoterol acts as an apparent β2‐AR/Gs selective agonist and fully restores diminished β2‐AR contractile response in cardiomyocytes from failing hearts of spontaneously hypertensive rats (SHR). Here we report the separation of the enantiomers of rac‐fenoterol and that R‐F is the active component of rac‐fenoterol. Further evaluation of R‐F will determine if it has enhanced selectivity and specificity for β2‐AR/Gs activation and if it can be used in the treatment of congestive heart failure. Chirality, 2006. Published 2006 Wiley‐Liss, Inc.
Particular subpopulations of midbrain and hypothalamic dopamine neurons express vesicular glutamate transporter 2 in the rat brain
Authors: Kawano Michihiro , Kawasaki Akiko , Sakata‐Haga Hiromi , Fukui Yoshihiro , Kawano Hitoshi , Nogami Haruo , Hisano Setsuji
Published: August 2006

Vesicular glutamate transporters (VGLUT1, ‐2, and ‐3) mediate the accumulation of transmitter glutamate into synaptic vesicles in glutamatergic neurons. VGLUT1 and VGLUT2 are more reliable glutamatergic neuron markers, since VGLUT3 also exists in other neuron types. To study whether the dopaminergic neuron uses glutamate as a cotransmitter, we analyzed VGLUTs expression in dopamine neurons of adult male rats by in situ hybridization and immunohistochemistry. In the ventral midbrain, in situ hybridization analysis revealed no VGLUT1 mRNA expression, a widespread but discrete pattern of VGLUT2 mRNA expression, and a highly limited expression of VGLUT3 mRNA. Reverse‐transcriptase polymerase chain reaction analysis detected full‐length VGLUT2 gene transcripts in the ventral midbrain. Using in situ hybridization combined with tyrosine hydroxylase (TH) immunostaining, only VGLUT2 signals were detectable in some TH‐labeled neurons of A10 dopamine neuron groups, with the highest incidence (20%) in the rostral linear nucleus of the ventral tegmental area. In the forebrain, VGLUT2 signals were demonstrated in half of the A11 TH‐labeled neurons in the hypothalamus. Double‐label immunostaining for VGLUT2 and vesicular monoamine transporter 2 or TH showed that double‐labeled varicosities are rarely observed in any target regions examined of A10 and A11 dopamine neuron groups. These results indicate that VGLUT2 is expressed in subsets of A10 and A11 dopamine neurons, which might release dopamine and glutamate separately from different varicosities in the majority of their single axons. J. Comp. Neurol. 498:581–592, 2006. © 2006 Wiley‐Liss, Inc.
Distinct structure and activity of monoamine oxidase in the brain of zebrafish (Danio rerio)
Authors: Anichtchik Oleg , Sallinen Ville , Peitsaro Nina , Panula Pertti
Published: August 2006

Monoamine oxidase (MAO) is a mitochondrial flavoprotein involved in the metabolism of, e.g., aminergic neurotransmitters and the parkinsonism‐inducing neurotoxin 1‐methyl‐4‐phenyl‐1,2,5,6‐tetrahydropyridine (MPTP). We have reported earlier MPTP‐related alterations of brain catecholaminergic system in zebrafish (Danio rerio) brain. Here we describe the structural and functional properties of zebrafish MAO and the distribution of MAO mRNA and activity in zebrafish brain. The gene is located in chromosome 9 and consists of 15 exons. The amino acid composition of the active center resembles both human MAO‐A and MAO‐B. The enzyme displayed the highest substrate specificity for tyramine, followed by serotonin, phenylethylamine, MPTP, and dopamine; isoform‐specific antagonists blocked the activity of the enzyme with equal potency. Zebrafish MAO mRNA, which was present in several tissues, and enzyme displayed differential distribution in the brain; dopaminergic cell clusters had low to moderate levels of MAO activity, whereas the highest levels of MAO activity were detected in noradrenergic and serotonergic cell groups and the habenulointerpeduncular pathway, including its caudal projection to the medial ventral rhombencephalon. The results of this study confirm the presence of functionally active MAO in zebrafish brain and other tissues and characterize the neural systems that express MAO and areas of intense activity in the brain. They also suggest that MPTP toxicity not related to MAO may affect the zebrafish brain. J. Comp. Neurol. 498:593–610, 2006. © 2006 Wiley‐Liss, Inc.
Diminished hypothalamic bdnf expression and impaired VMH function are associated with reduced SF‐1 gene dosage
Authors: Tran Phu V. , Akana Susan F. , Malkovska Irena , Dallman Mary F. , Parada Luis F. , Ingraham Holly A.
Published: August 2006

In the central nervous system, steroidogenic factor 1 (SF‐1) is required for terminal differentiation of neurons within the ventromedial hypothalamus (VMH). Given the importance of this brain region in regulating physiological homeostasis including energy balance, we asked how sf‐1 gene dosage affects VMH function. Despite an apparent normal VMH cytoarchitecture, sf‐1 heterozygous (+/−) mice exhibited diet‐induced obesity when they were group housed with hyperphagia and impaired sympathetic activity. On the basis of previous findings suggesting brain‐derived neurotrophic factor (bdnf) as an SF‐1 target gene, we assessed the colocalization of SF‐1 and BDNF expressing neurons, as well as expression of the four exon‐specific bdnf promoter transcripts in the VMH. Indeed, a subset of neurons located primarily in the ventrolateral VMH coexpress SF‐1 and BDNF, and in contrast to other brain regions, bdnf I, II, and IV but not III are found. Consistent with these findings, cellular assays showed that SF‐1 is able to activate exon I and IV promoters. More important, levels of bdnf I and IV in the VMH were reduced in heterozygous mice similar to levels observed in fasted wild‐type mice. Collectively, we propose that a reduction in the sf‐1 gene dosage directly affects BDNF levels in the VMH and disrupts normal hypothalamic function. J. Comp. Neurol. 498:637–648, 2006. © 2006 Wiley‐Liss, Inc.
Differential c‐Fos immunoreactivity in arousal‐promoting cell groups following systemic administration of caffeine in rats
Authors: Deurveilher Samüel , Lo Henry , Murphy Jeremy A. , Burns Joan , Semba Kazue
Published: August 2006

Despite the widespread use of caffeine, the neuronal mechanisms underlying its stimulatory effects are not completely understood. By using c‐Fos immunohistochemistry as a marker of neuronal activation, we recently showed that stimulant doses of caffeine activate arousal‐promoting hypothalamic orexin (hypocretin) neurons. In the present study, we investigated whether other key neurons of the arousal system are also activated by caffeine, via dual immunostaining for c‐Fos and transmitter markers. Rats were administered three doses of caffeine or saline vehicle during the light phase. Caffeine at 10 and 30 mg/kg, i.p., increased motor activities, including locomotion, compared with after saline or a higher dose, 75 mg/kg. The three doses of caffeine induced distinct dose‐related patterns of c‐Fos immunoreactivity in several arousal‐promoting areas, including orexin neurons and adjacent neurons containing neither orexin nor melanin‐concentrating hormone; tuberomammillary histaminergic neurons; locus coeruleus noradrenergic neurons; noncholinergic basal forebrain neurons that do not contain parvalbumin; and nondopaminergic neurons in the ventral tegmental area. At any dose used, caffeine induced little or no c‐Fos expression in cholinergic neurons of the basal forebrain and mesopontine tegmentum; dopaminergic neurons of the ventral tegmental area, central gray, and substantia nigra pars compacta; and serotonergic neurons in the dorsal raphe nucleus. Saline controls exhibited only few c‐Fos‐positive cells in most of the cell groups examined. These results indicate that motor‐stimulatory doses of caffeine induce a remarkably restricted pattern of c‐Fos expression in the arousal‐promoting system and suggest that this specific neuronal activation may be involved in the behavioral arousal by caffeine. J. Comp. Neurol. 498:667–689, 2006. © 2006 Wiley‐Liss, Inc.
Long‐range interneurons within the medial pulvinar nucleus of macaque monkeys
Authors: Imura Kosuke , Rockland Kathleen S.
Published: August 2006

Like other thalamic nuclei, the primate pulvinar is considered not to have long‐range intrinsic connections, either excitatory or inhibitory. Injections of biotinylated dextran amine (BDA) in the medial pulvinar, however, reveal retrogradely filled neurons up to 2.0 mm from the injection edge. Serial section reconstruction (n = 18) confirmed that retrogradely filled neurons projected to the injection site and showed that they had additional long‐range collaterals within the posterior pulvinar. Arrays of small, beaded terminations occurred in multiple foci along the collaterals. Terminal arrays were up to 1.0 mm in length; foci were separated by about 0.7 mm. Somata were large (average area = 220 μm2), and dendritic arbors were radiate and also large (about 1.0 mm in diameter), but without either the appendages of classical interneurons or the hairlike spines characteristic of radiate pulvinocortical projection neurons. Double labeling for BDA and parvalbumin (PV) or BDA and γ‐aminobutyric acid (GABA) indicated that these large neurons were positive for both PV and GABA. Double labeling for PV and GABA, or PV and glutamic acid decarboxylase 67 (GAD67) revealed a small number of similarly large neurons in the posterior pulvinar that were positive for both substances. Thus, we propose that these neurons are a novel class of inhibitory interneuron, longer range than the classic thalamic local circuit interneurons. Future questions include how these neurons relate to other inhibitory systems and specific postsynaptic populations and whether they are located preferentially within the posterior pulvinar, possibly related to the multimodal character of this thalamic region. J. Comp. Neurol. 498:649–666, 2006. © 2006 Wiley‐Liss, Inc.
Experiments of the improvement in the performance of a disk CCMHD generator
Authors: Murakami Tomoyuki , Okuno Yoshihiro , Yamasaki Hiroyuki
Published: August 2006

The present experiment has aimed at the improvement in the performance of a shock‐tube‐driven disk CCMHD generator. For that purpose, an experimental setup was arranged as follows: (1) An inlet swirl was introduced. (2) The area ratio of the disk generator was small. (3) A cesium‐seeded helium gas was used as a working medium. Not only these factors but also the production of a homogeneous plasma contributed to outstanding performance characterized by an isentropic efficiency of 63% and an enthalpy extraction ratio of 30.8% at a stagnation temperature of 2250 K and stagnation pressure of 0.14 MPa. Furthermore, a maximum electrical power output of 1.23 MW and a maximum power density of 297 MW/m3 were obtained. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(2): 24–31, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20024
Magnetic properties of Pr‐Fe‐Co‐V‐W‐Si‐B system exchange spring magnets
Authors: Yamamoto Hiroshi , Nakanishi Takashi
Published: August 2006

The melt‐spun ribbons of Pr‐Fe‐Co‐V‐W‐Si‐B system alloys were prepared by single roller rapid‐quenching method. The effects of composition, surface velocity, and heat treatment on the magnetic properties were investigated. The P9sFe71Co8V0.5W0.5Si0.5B10.5 alloy ribbons prepared at a surface velocity of 12.5 m/s were crystallized by heat treatment, and the optimum heat‐treatment condition was found to be at 575°C for 3 min, for which the magnetic properties were (BH)max = 136.1 kJ/m3, Jr = 0.93 T, HcJ = 652.2 kA/m, and HcB = 528.3 kA/m. The temperature coefficients of Jr and HcJ for the ribbons crystallized from melt‐spun ribbons of Pr9Fe71Co8V0.5W0.5Si0.5B10.5 alloy were α(Jr)ave = −0.057%/°C and α(HcJ) = −0.450%/°C. The value of (B)max for the compression molding Pr9Fe71Co8V0.5W0.5Si0.5B10.5 isotropic bonded magnet prepared by using the ribbons annealed at 575°C for 3 min is 80.0 kJ/m3, and the density is 6.24 Mg/m3. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(3): 10–16, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20211 Copyright © 2006 Wiley Periodicals, Inc.
Conditions of atmospheric electricity variation during seismic wave propagation
Authors: Okubo Kan , Yamamoto Keisuke , Takayama Masakazu , Takeuchi Nobunao
Published: August 2006

This study reports the observation of co‐seismic electromagnetic phenomena, including earth potential difference (EPD) variation and atmospheric electricity (AE) variation, at three observation sites in Akita Prefecture. During the strong earthquake of 2 December, we observed clear signals of EPD and AE variation at all three sites. However, the amplitudes of both observed signals at those three sites differ greatly, but have almost equal quake intensity at each site. The AE signal's amplitude increases along with the increase in amplitude of the EPD signal at every site. A model describing the appearance of both variation signals is proposed to explain the observed data. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(3): 1–9, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20230 Copyright © 2006 Wiley Periodicals, Inc.
A new MPPT control for photovoltaic panels by instantaneous maximum power point tracking
Authors: Tokushima Daiki , Uchida Masato , Kanbei Satoshi , Ishikawa Hiroki , Naitoh Haruo
Published: August 2006

This paper presents a new maximum power point tracking control for photovoltaic (PV) panels. The control can be categorized into the Perturb and Observe (P&O) method. It utilizes instantaneous voltage ripples at PV panel output terminals caused by the switching of a chopper connected to the panel in order to identify the direction for the maximum power point (MPP). The tracking for the MPP is achieved by a feedback control of the average terminal voltage of the panel. Appropriate use of the instantaneous and the average values of the PV voltage for the separate purposes enables both the quick transient response and the good convergence with almost no ripples simultaneously. The tracking capability is verified experimentally with a 2.8‐W PV panel under a controlled experimental setup. A numerical comparison with a conventional P&O confirms that the proposed control extracts much more power from the PV panel. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(3): 73–80, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20255 Copyright © 2006 Wiley Periodicals, Inc.
Thresholding algorithm for local and parallel processing
Authors: Iwakata Satoshi , Ajioka Yoshiaki , Hagiwara Masafumi
Published: August 2006

In this paper, we propose a thresholding algorithm. This algorithm works under a severe constraint: each pixel in a processed image must be derived from only information of its neighboring pixels. This constraint is very important for a low‐cost device such as a mobile camera, because it makes it possible to process each pixel in parallel. The proposed algorithm deals with gray‐scale images, and determines the threshold based on edge information. The proposed algorithm is represented by local and parallel image processing and has been tested using 104 scenery images. The result shows that the proposed algorithm can binarize images. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(2): 50–56, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20267
High‐efficiency UV LEDs using quaternary InAlGaN
Authors: Hirayama Hideki , Kyono Takashi , Akita Katsushi , Nakamura Takao , Ishibashi Koji
Published: August 2006

High‐efficiency ultraviolet (UV) light sources are very attractive for application to the medical field, white lighting, high‐density memories, and so on. We have demonstrated that 300‐ to 370‐nm UV emission is considerably enhanced by the introduction of several percent of In into AlGaN due to an In‐segregation effect. We fabricated 310‐nm‐band UV LEDs with quaternary InAlGaN emitting layers on a sapphire substrate and obtained submilliwatt output power. We also fabricated 350‐nm‐band InAlGaN‐based quantum‐well LEDs on GaN substrates in order to eliminate the effects of threading dislocations. The maximum UV output power obtained was as high as 7.4 mW under room‐temperature CW operation. The maximum external quantum efficiency (EQE) was 1.1% with an injection current of 50 mA, which is the highest EQE ever obtained for 350‐nm‐band UV LEDs with top‐emission geometry. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(3): 43–51, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20287 Copyright © 2006 Wiley Periodicals, Inc.
Measurement of sparkover voltage and time lag characteristics in CF3I–N2 and CF3I– air gas mixtures by using steep‐front square voltage
Authors: Toyota Hiroyuki , Matsuoka Shigeyasu , Hidaka Kunihiko
Published: August 2006

A square pulse voltage is useful for studying electrical discharge physics or very fast transient overvoltage issues. This paper describes sparkover voltages and time lag (V– t) characteristics of CF3I gas, which has very low environmental effects and high dielectric strength, and its mixtures with nitrogen gas or air in a very short time range below a microsecond. They are measured by using a steep‐front square voltage with a rise time of 16 ns and a peak value of 200 kV. Pure CF3I gas has 20% higher dielectric strength than SF6 gas. The V– t characteristics of CF3I–N2 or CF3I– air gas mixtures, which contain 60% CF3I gas, are equivalent to those of pure SF6 gas at the same total pressure. A quantitative evaluation of V– t characteristics by the equal‐area criterion is also performed. The equal‐area parameter which is obtained by applying a voltage high enough to make the formative time lag dominant should be chosen. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(2): 1–7, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20325
A method for mixed integer programming problems by particle swarm optimization
Authors: Kitayama Satoshi , Yasuda Keiichiro
Published: August 2006

Particle Swarm Optimization (PSO) for mixed integer programming problems is proposed. PSO is mainly a method to find a global or quasi‐minimum for a nonlinear and nonconvex optimization problem, and there have been few studies into optimization problems with discrete decision variables. In this paper, we present the treatment of discrete variables. To treat discrete decision variables as a penalty function, it is possible to treat all decision variables as a continuous decision variable. As a result, the penalty parameter for the penalty function is needed. In this paper, we also present how to determine the penalty parameter for the penalty function. Through mathematical and structural optimization problems, we examine the validity of PSO for the mixed decision variables. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(2): 40–49, 2006; Published onlinein Wiley InterScience www.interscience.wiley.com). DOI 10.1002/eej.20337
A study on visibility estimation of web‐safe colors using paired comparison and discriminant analysis
Authors: Saito Daisuke , Saito Keiichi , Notomi Kazuhiro , Saito Masao
Published: August 2006

This paper describes the visibility ordering of several web‐safe colors, particularly in relation to age. The rapid dissemination of the World Wide Web has increased the importance of web page visibility research. The combination of foreground and background colors is an important factor in providing sufficient visibility, and the rating of color combination visibility should be considered when developing accessible websites. In this study, the visibility of several web‐safe color combinations was examined using psychological methodology, that is, paired comparison. Visual stimuli were 18 chromatic and 3 achromatic web‐safe colors. Twenty‐eight subjects ranging in age from 21 to 75 were recruited, and all had normal color sensation. Subjects looked at two different colored characters simultaneously on a white background and were instructed to identify which they could see more clearly. To examine the relationship between psychological rankings of the color combinations and visual sensations, each color combination was first scored with regard to visibility by Thurstone's paired comparison technique. Second, visual sensation was deduced by applying Weber‐Fechner's law to the luminance of the foreground colors. The results indicated that the luminance of a foreground color influenced visibility of web‐safe colors; however, luminance alone was not sufficient to make a visibility rating. Chromaticity and chroma saturation are also necessary in the rating of chromatic web‐safe color visibility. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(2): 32–39, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20400
A calculation method of the total efficiency of wind generators
Authors: Inoue Akira , Takahashi Rion , Murata Toshiaki , Tamura Junji , Kimura Mamoru , Futami Moto‐O , Ide Kazumasa
Published: August 2006

The spread of wind energy converters is progressing in recent years and its capacity is becoming larger and larger. In order to capture more energy from the wind, it is important to analyze loss characteristics of wind generators for the operating speed which is determined dependent on the wind speed. This paper presents a method to evaluate various losses in a wind generator as a function of wind speed, which is based on steady‐state analysis and thus the calculations can be performed quickly. By using the proposed method, wind turbine power, generator output, various losses, and the total energy efficiency are calculated for three types of wind speed data which are represented by a Weibull function. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(3): 52–62, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20426 Copyright © 2006 Wiley Periodicals, Inc.
Minimum energy path search for a manipulator in consideration of all nonlinear characteristics by GA and its experiments
Authors: Izumi Teruyuki , Yokose Yoshio , Tamai Ryuichi
Published: August 2006

The dissipated energy even of a manipulator must be decreased in order to improve the environment of the earth. This paper describes an optimal path which minimizes the dissipated energy in PTP motions of a vertically articulated manipulator. The dynamic equation of the manipulator is nonlinear due to centrifugal, Coriolis, gravity, and Coulomb friction forces. Moreover the driving system of the joints is also nonlinear in that the generating torque is expressed by a third‐degree polynomial with respect to current. Therefore, an optimal path cannot be obtained by solving a two‐point boundary‐value problem analytically. In this paper an optimal path is searched for by a Genetic Algorithm (GA) in cases in which all kinds of nonlinear characteristics of the manipulator, including the driving system, are taken into consideration. The obtained optimal velocity functions are applied to a vertically articulated manipulator with two direct‐drive motors. The dissipated energy is measured by integrating the input power to the motors. Experimental results agree with the simulation values only when all kinds of nonlinearity are taken into consideration. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(3): 26–34, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20437 Copyright © 2006 Wiley Periodicals, Inc.
Palladium‐Catalyzed Coupling Reactions for the Functionalization of BODIPY Dyes with Fluorescence Spanning the Visible Spectrum
Authors: Rohand Taoufik , Qin Wenwu , Boens Noël , Dehaen Wim
Published: August 2006

The BODIPY fluorophore can easily be functionalized at the 3‐ (and 5‐)position(s) with one or two aryl, ethenylaryl and ethynylaryl moieties by palladium‐catalyzed coupling reactions of the 3,5‐dichloroBODIPY derivative using the Stille, Suzuki, Heck and Sonogashira reactions. The fluorescence excitation and emission spectral maxima of the novel BODIPY derivatives range from green to near‐infrared. The new class of ethynylaryl‐substituted BODIPY dyes are extremely bright fluorescent compounds.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Currency barrier option pricing with mean reversion
Authors: Hui C. H. , Lo C. F.
Published: August 2006

This article develops a barrier option pricing model in which the exchange rate follows a mean‐reverting lognormal process. The corresponding closed‐form solutions for the barrier options with time‐dependent barriers are derived. The numerical results show that barrier option values and the corresponding hedge parameters under the proposed model are different from those based on the Black‐Scholes model. For an up‐and‐out call, the mean‐reverting process keeps the exchange rate in a small range around the mean level. When the mean level is below the barrier but above the strike price, the risk of the call to be knocked out is reduced and its option value is enhanced compared with the value under the Black‐Scholes model. The parameters of the mean‐reverting lognormal process therefore have a material impact on the valuation of currency barrier options and their hedge parameters. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:939–958, 2006
Improved estimation of portfolio value‐at‐risk under copula models with mixed marginals
Authors: Miller Douglas J. , Liu Wei‐Han
Published: August 2006

Portfolio value‐at‐risk (PVAR) is widely used in practice, but recent criticisms have focused on risks arising from biased PVAR estimates due to model specification errors and other problems. The PVAR estimation method proposed in this article combines generalized Pareto distribution tails with the empirical density function to model the marginal distributions for each asset in the portfolio, and a copula model is used to form a joint distribution from the fitted marginals. The copula–mixed distribution (CMX) approach converges in probability to the true marginal return distribution but is based on weaker assumptions that may be appropriate for the returns data found in practice. CMX is used to estimate the joint distribution of log returns for the Taiwan Stock Exchange (TSE) index and the associated futures contracts on SGX and TAIFEX. The PVAR estimates for various hedge portfolios are computed from the fitted CMX model, and backtesting diagnostics indicate that CMX outperforms the alternative PVAR estimators. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:997–1018, 2006
Spot‐futures spread, time‐varying correlation, and hedging with currency futures
Authors: Lien Donald , Yang Li
Published: August 2006

This article investigates the effects of the spot‐futures spread on the return and risk structure in currency markets. With the use of a bivariate dynamic conditional correlation GARCH framework, evidence is found of asymmetric effects of positive and negative spreads on the return and the risk structure of spot and futures markets. The implications of the asymmetric effects on futures hedging are examined, and the performance of hedging strategies generated from a model incorporating asymmetric effects is compared with several alternative models. The in‐sample comparison results indicate that the asymmetric effect model provides the best hedging strategy for all currency markets examined, except for the Canadian dollar. Out‐of‐sample comparisons suggest that the asymmetric effect model provides the best strategy for the Australian dollar, the British pound, the deutsche mark, and the Swiss franc markets, and the symmetric effect model provides a better strategy than the asymmetric effect model in the Canadian dollar and the Japanese yen. The worst performance is given by the naïve hedging strategy for both in‐sample and out‐of‐sample comparisons in all currency markets examined. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:1019–1038, 2006
A comparison of methods for intermediate fine mapping
Authors: Papachristou Charalampos , Lin Shili
Published: August 2006

The arrival of highly dense genetic maps at low cost has geared the focus of linkage analysis studies toward developing methods for placing putative trait loci in narrow regions with high confidence. This shift has led to a new analytic scheme that expands the traditional two‐stage protocol of preliminary genome scan followed by fine mapping through inserting a new stage in between the two. The goal of this new “intermediate” fine mapping stage is to isolate disease loci to narrow intervals with high confidence so that association studies can be more focused, efficient, and cost‐effective. In this paper, we compared and contrasted five methods that can be used for performing this intermediate step. These methods are: the lod support approach, the generalized estimating equations (GEE) method, the confidence set inference (CSI) procedure, and two bootstrap methods. We compared these methods in terms of the coverage probability and precision of localization of the resulting intervals. Results from a simulation study considering several two‐locus models demonstrated that the two bootstrap methods yield intervals with approximately correct coverage. On the other hand, the 1‐lod support intervals, and those produced by the GEE method, tend to significantly undercover the trait locus, while the regions obtained by the CSI incline to overcover the gene position. When the observed coverage of the confidence intervals produced by all the methods was held to be the same, those obtained through the CSI procedure displayed a higher ability to localize loci, especially when these loci have a minor contribution to the trait and when the amount of data available for the analysis is relatively small. However, with very large sample sizes, lod support intervals emerged as a winner. Application of the methods to the data from the Arthritis Research Campaign National Repository led to intervals containing the position of a known trait locus for all methods, with the greatest precision achieved by the CSI. Genet. Epidemiol. 2006. © 2006 Wiley‐Liss, Inc.
Pharmacokinetic parameters of bromperidol in Korean subjects
Authors: Lee Soo‐Youn , Kim Yoon Gyoon , Kim Hyung‐Gun , Kim Jong‐Won
Published: August 2006

We have presented pharmacokinetic parameters of bromperidol (BP) in 14 healthy Korean subjects. Additionally, we have investigated the effects of dose and genetic polymorphisms on BP metabolism and on extrapyramidal symptoms (EPS). The Tmax (3.9 ± 0.9 h), clearance (1.37 ± 0.52 ml/h/kg), and t1/2 (20.4 ± 3.7 h) obtained in our study are comparable to those in previous Caucasian studies, although pharmacokinetic profiles were affected by the BP dose. We could not prove any significant correlations between BP metabolism or adverse effects and genetic factors because the number of subjects was small. Further studies with a larger population are needed to determine the influence of genetic factors on BP therapy. Copyright © 2006 John Wiley & Sons, Ltd.