bluuebunny/crossref_metadata_2025 huggingface dataset:
Solid‐Phase Synthesis of a Cyclic NGR‐Functionalized GdIIIDTPA Complex
Authors: Langereis Sander , Dirksen Anouk , De Waal Bas F. M. , Van Genderen Marcel H. P. , De Lussanet Quido G. , Hackeng Tilman M. , Meijer E. W.
Published: June 2005

A convenient methodology has been developed for the solid‐phase synthesis of a cyclic NGR‐functionalized GdIIIDTPA complex employing an isocyanate‐functionalized DTPA pentaester. This methodology is an alternative strategy for the tagging of oligopeptides with GdIIIDTPA as an MRI label on the solid phase. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Cover Picture: Elemental Fluorine and HOF·CH3CN in Service of General Organic Chemistry (Eur. J. Org. Chem. 12/2005)
Authors: Rozen Shlomo
Published: June 2005

The cover picture shows part of the synthetic possibilities opened now by using elemental fluorine as a starting material. Mixtures of F2 with inert gases such as N2 are commercially available or easily prepared from commercial 95% fluorine. During the last 15 years, chemists started to accept the notion that F2 could be used for fluorination purposes. More recently, they slowly started to get acquainted with yet another side of this element − its ability to perform difficult reactions leading to fluorine‐free derivatives. Thus, the most reactive element of the periodic table is an excellent tool for versatile regio‐ and stereospecific reactions which can not be performed without its “help”. Representative examples are presented in the Microreview by S. Rozen on p. 2433 ff.
Methodological issues relating to in vivo cortical myelography using MRI
Authors: Clare Stuart , Bridge Holly
Published: June 2005

The relationship between neocortical structure and function is a key area of research in neuroscience. Most studies of neural function, whether using neurophysiology or neuroimaging methods, are interpreted with relation to the underlying cortical myelo‐ and cytoarchitecture. For functional neuroimaging studies this often means using cytoarchitectonic maps based on the study of a limited number of brains, despite evidence for substantial interindividual variation. Improvements in MR technology, resulting in wider availability of high‐field MRI systems, have led to an increase in the achievable resolution in MR scans. Several groups have reported the in vivo detection of myelination patterns within the cortex, consistent with those observed in postmortem tissue. This leads to the possibility of predefining areas for fMRI analysis based on the cortical architecture. To do this it is essential to know, in a quantitative way, how reliably myeloarchitectonic areas and boundaries can be detected using MRI. Here we investigate the striate cortex, known to be coincident with V1, to assess the detectability of the stria of Gennari across V1 and across subjects. Under optimal conditions, 80% of the stria of Gennari was visualized using our methodology, although there was considerable variability in the level of detection across subjects. We discuss the limitations of the methodology and propose ways to improve the detection level of cortical myeloarchitecture more generally. Hum. Brain Mapping, 2005. © 2005 Wiley‐Liss, Inc.
Human brain activation during passive listening to sounds from different locations: An fMRI and MEG study
Authors: Brunetti M. , Belardinelli P. , Caulo M. , Del Gratta C. , Della Penna S. , Ferretti A. , Lucci G. , Moretti A. , Pizzella V. , Tartaro A. , Torquati K. , Olivetti Belardinelli M. , Romani G.L.
Published: June 2005

Recent animal and human studies indicate the existence of a neural pathway for sound localization, which is similar to the “where” pathway of the visual system and distinct from the sound identification pathway. This study sought to highlight this pathway using a passive listening protocol. We employed fMRI to study cortical areas, activated during the processing of sounds coming from different locations, and MEG to disclose the temporal dynamics of these areas. In addition, the hypothesis of different activation levels in the right and in the left hemispheres, due to hemispheric specialization of the human brain, was investigated. The fMRI results indicate that the processing of sound, coming from different locations, activates a complex neuronal circuit, similar to the sound localization system described in monkeys known as the auditory “where” pathway. This system includes Heschl's gyrus, the superior temporal gyrus, the supramarginal gyrus, and the inferior and middle frontal lobe. The MEG analysis allowed assessment of the timing of this circuit: the activation of Heschl's gyrus was observed 139 ms after the auditory stimulus, the peak latency of the source located in the superior temporal gyrus was at 156 ms, and the inferior parietal lobule and the supramarginal gyrus peaked at 162 ms. Both hemispheres were found to be involved in the processing of sounds coming from different locations, but a stronger activation was observed in the right hemisphere. Hum. Brain Mapping, 2005. © 2005 Wiley‐Liss, Inc.
Viral and Host Factors in Early Hepatitis C Virus Infection *
Authors: Mosley James W. , Operskalski Eva A. , Tobler Leslie H. , Andrews William W. , Phelps Bruce , Dockter Janel , Giachetti Cristina , Busch Michael P.
Published: June 2005

Since 1980, the Transfusion-transmitted Viruses Study (TTVS) (1974–1980) has continued to maintain its computerized database and stored sera to enable ongoing study of new transfusion events since the 1970s. Most recently, we have used this resource to study parameters of acute hepatitis C virus (HCV) infection among 94 donor–recipient pairs in which there was transmission. In addition, frequent recipient observations permitted further characterization of the early phase of the infection's course. Donor RNA load ranged from 3.7 to 3,160,000 IU/mL. Onset of recipient viremia was judged from a total of 67 sera collected during the 4th through 8th days posttransfusion; only 2 of the 67 sera were still RNA nonreactive by that time. The recipients' latent periods to an alanine aminotransferase (ALT) elevation of ≥90 IU/L ranged from 6 to 112 days (median, 46 days) and was shorter with higher donor RNA levels. Descriptors of the recipient's illness showed several strongly positive and negative correlations. The latent period tended to be shorter in the 37% of cases that were clinically overt. Attributes of donors with genotypes 1 and non-1 and subtypes 1a and 1b did not differ significantly. Recipients with genotype 1 strains had shorter latent intervals than non-1 strains. On multivariate analysis, latent period was significantly associated (negatively) only with the highest ALT level during the first 120 days of follow-up (

P

= .014).
In conclusion
, host factors are more important determinants of acute HCV infection dynamics than virus-associated factors. (Hepatology 2005.)
SCUD: Fast structure clustering of decoys using reference state to remove overall rotation
Authors: Li Hongzhi , Zhou Yaoqi
Published: June 2005

We developed a method for fast decoy clustering by using reference root‐mean‐squared distance (rRMSD) rather than commonly used pairwise RMSD (pRMSD) values. For 41 proteins with 2000 decoys each, the computing efficiency increases nine times without a significant change in the accuracy of near‐native selections. Tests on additional protein decoys based on different reference conformations confirmed this result. Further analysis indicates that the pRMSD and rRMSD values are highly correlated (with an average correlation coefficient of 0.82) and the clusters obtained from pRMSD and rRMSD values are highly similar (the representative structures of the top five largest clusters from the two methods are 74% identical). SCUD (Structure ClUstering of Decoys) with an automatic cutoff value is available at http://theory.med.buffalo.edu. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1189–1192, 2005
Analysis of natural antioxidants by capillary electromigration methods
Authors: Herrero Miguel , Ibáñez Elena , Cifuentes Alejandro
Published: June 2005

In this work, an exhaustive survey of capillary electromigration methods used to analyze natural antioxidants is presented together with some discussion of the use of these substances use as functional foods. This review provides an updated and exhaustive overview of the separation and identification by capillary electrophoresis of natural compounds with antioxidant activity found in natural matrices and/or foods. The compounds concerned are catechins, isoflavones, anthocyanins, phenolic acids, vitamins, as well as other less common natural substances that have shown antioxidant activity.
Composition and analysis of liquid smoke flavouring primary products
Authors: Simon Rupert , de la Calle Beatriz , Palme Sonja , Meier Dietrich , Anklam Elke
Published: June 2005

Smoke flavourings are produced on a large scale and have been applied to a variety of food products for more than 30 years. The use of them has many advantages compared to traditional smoking techniques. Among others, the amount of (known) toxic compounds deriving from combustion processes can be more easily controlled in smoke flavourings. In order to ensure safe products, a new European Regulation requests data on the composition and lays down, in particular, the maximum permitted concentrations for selected polycyclic aromatic hydrocarbons (PAHs). This review compiles results published on the chemical composition of liquid smoke flavouring primary products, partly in relation to production process parameters, and the analytical methods involved. The methods cover chromatographic techniques for analysis of specific compounds including extraction methods and clean‐up procedures. Analysis of sensorial and bulk parameters such as acidity and total phenolic compounds are described as well as they are used as standard methods for analysis of liquid smoke flavourings. A special section is devoted to discussing the analysis of PAHs.
Caillary electrophoresis for the analysis of meat authenticity
Authors: Vallejo‐Cordoba Belinda , González‐Córdova Aarón F. , Mazorra‐Manzano Miguel A. , Rodríguez‐Ramírez Roberto
Published: June 2005

In this overview, different meat authenticity issues are presented, as well as a wide variety of methods available for meat authentication. Unlike chromatographic, traditional gel electrophoretic, or immunological methods, which have been routinely used in analytical laboratories, the application of capillary electrophoresis (CE) is relatively new in solving meat authentication issues. Several unique CE applications based on meat protein fingerprinting are discussed for the analysis of meat species in unheated meat products. For protein data interpretation, pattern recognition is used to account for the natural variability present within the same meat species. While gel DNA‐based methods are widely used for determining meat species in heat processed products, few DNA‐based methods utilizing CE have been reported. Moreover, the methods reported are qualitative or semiquantitative. Thus, the need for quantitative competitive PCR CE methods in the determination of meat species is addressed. For the determination of meat extenders, CE methods were either protein‐based or based on specific markers. Polyphenols are used as specific markers for soy detection and hydroxyproline is used as a specific marker for collagen determination. Finally, the potential of electrophoretically mediated miroanalysis (EMMA) for the detection of meat that may have been previously frozen and retailed as “fresh” is highlighted.
Analysis of pesticides in soy milk combining solid‐phase extraction and capillary electrophoresis‐mass spectrometry
Authors: Hernández‐Borges Javier , Rodríguez‐Delgado Miguel Ángel , García‐Montelongo Francisco J. , Cifuentes Alejandro
Published: June 2005

In this work, the determination of a group of triazolopyrimidine sulfoanilide herbicides (cloransulam‐methyl, metosulam, flumetsulam, florasulam, and diclosulam) in soy milk by capillary electrophoresis‐mass spectrometry (CE‐MS) is presented. The main electrospray interface (ESI) parameters (nebulizer pressure, dry gas flow rate, dry gas temperature, and composition of the sheath liquid) are optimized using a central composite design. To increase the sensitivity of the CE‐MS method, an off‐line sample preconcentration procedure based on solid‐phase extraction (SPE) is combined with an on‐line stacking procedure (i. e. normal stacking mode, NSM). Samples could be injected for up to 100 s, providing limits of detection (LODs) down to 74 μg/L, i. e., at the low ppb level, with relative standard deviation values (RSD,%) between 3.8% and 6.4% for peak areas on the same day, and between 6.5% and 8.1% on three different days. The usefulness of the optimized SPE‐NSM‐CE‐MS procedure is demonstrated through the sensitive quantification of the selected pesticides in soy milk samples.
Development of a perfusion reversed‐phase HPLC method for the separation of soybean and cereal (wheat, corn, and rice) proteins in binary mixtures. Application to the detection of soybean proteins in commercial bakery products
Authors: Castro‐Rubio A. , Castro‐Rubio F. , García M. C. , Marina M. L.
Published: June 2005

A perfusion reversed‐phase HPLC method enabling the simultaneous separation of soybean and cereal (wheat, corn, and rice) proteins in commercial bakery products has been proposed for the first time. The method utilises an acetonitrile‐water gradient containing an ion‐pairing agent. Different ion‐pairing agents were tried, 0.3% (v/v) acetic acid being observed to enable the separation of soybean from wheat, rice, and corn proteins while with 0.1% (v/v) trifluoroacetic acid only the separation of soybean and corn proteins was possible. Optimisation of the solubilisation conditions for proteins was achieved by testing different acetonitrile concentrations for the simultaneous extraction of soybean and cereal proteins: best recoveries were found with 25% (v/v) acetonitrile + 0.3% (v/v) acetic acid and with 40% (v/v) acetonitrile + 0.1% (v/v) trifluoroacetic acid. Chromatographic conditions such as gradient, temperature, and wavelength detection were also optimised. The method enabled the separation of soybean and cereal proteins in binary mixtures (soybean and wheat, soybean and corn, or soybean and rice proteins) in less than 5 minutes in a total analysis time of 20 min.
Analysis of trace amounts of bovine β‐lactoglobulin in infant formulas by capillary electrophoresis with on‐capillary derivatization and laser‐induced fluorescence detection
Authors: Veledo María Teresa , de Frutos Mercedes , Diez‐Masa José Carlos
Published: June 2005

Bovine β‐lactoglobulin (βLG) has been described by several authors as the main allergen present in cow's milk. It can induce allergic reactions even at the low concentration existing in hypoallergenic formulas based on hydrolyzed cow's milk proteins (generally lower than μM). In this paper, the usefulness of a capillary electrophoresis method with on‐capillary derivatization and laser‐induced fluorescence detection for the analysis of trace amounts of βLG in a commercial hypoallergenic formula has been demonstrated. To confirm the identity of the peak of βLG based on migration time, an immunorecognition step employing an anti‐βLG antibody was performed. βLG was quantitated in the whey and casein fractions of the hypoallergenic formula. The concentration of βLG in the whey fraction of the formula was about 3 orders of magnitude lower than the average value present in cow's milk. In the casein fraction of the formula, the concentration of βLG was about 1 order of magnitude lower than in the whey fraction. The method developed was also used for the quality control of three cereal‐based infant foods formulated without milk to test the presence or absence of βLG as an indicator of milk contamination during the fabrication process. βLG in a concentration of 10–7 M or higher was not observed in any of the cereal‐based infant formulas analyzed.
Reliable characterization of coffee bean aroma profiles by automated headspace solid phase microextraction‐gas chromatography‐mass spectrometry with the support of a dual‐filter mass spectra library
Authors: Mondello Luigi , Costa Rosaria , Tranchida Peter Quinto , Dugo Paola , Lo Presti Maria , Festa Saverio , Fazio Alessia , Dugo Giovanni
Published: June 2005

This investigation is based on the automated solid phase microextraction GC‐MS analysis of the volatile fraction of a variety of coffee bean matrices. Volatile analytes were extracted by headspace (HS)‐SPME which was achieved with the support of automated instrumentation. The research was directed towards various important aspects relating to coffee aroma analysis: monitoring of the volatile fraction formation during roasting; chromatographic differentiation of the two main coffee species (Arabica and Robusta) and of a single species from different geographical origins; evaluation of the influence of specific industrial treatments prior to roasting. Reliable peak assignment was carried out through the use of a recently laboratory‐constructed “flavour and fragrance” library and a dual‐filter MS spectral search procedure. Further emphasis was placed on the automated SPME instrumentation and on its ability to supply highly repeatable chromatographic data.
Analytical approaches to expanding the use of capillary electrophoresis in routine food analysis
Authors: Castañeda Gregorio , Rodríguez‐Flores Juana , Ríos Angel
Published: June 2005

Capillary Electrophoresis (CE) is becoming an ever more powerful analytical technique for the separation, identification, and quantification of a wide variety of compounds of interest in many application fields. Particularly in food analysis this technique can offer interesting advantages over chromatographic techniques because of its greater simplicity and efficiency. Nevertheless, CE needs to advance with regard to compatibility with sample matrices, sensitivity, and robustness of the methodologies in order to gain even wider acceptance in food analysis laboratories, specially for routine work. This article presents various approaches to expanding the analytical usefulness of CE in food analysis, discussing their advantages over conventional CE. These approaches focus on sample screening, automated sample preparation with on‐line CE arrangements, and the automatic integration of calibration in routine analytical work with CE.
Determination of organic contaminants in food by capillary electrophoresis
Authors: Juan‐García Ana , Font Guillermina , Picó Yolanda
Published: June 2005

This review addresses recent advances in the analysis of organic contaminants, such as antibiotics, pesticides, biological toxins, and food‐borne pathogens, in foods by capillary electrophoresis (CE). Special attention is paid to those aspects that increase sensitivity and/or selectivity, such as sample extraction and concentration, on‐line preconcentration techniques (stacking), affinity capillaries or/and specific detectors (laser induced fluorescence (LIF), mass spectrometry (MS)). The various CE modes used to separate the compounds and the quantification strategies are also examined. As a result, this work presents an updated overview on the principal applications of CE, together with a discussion of their main advantages and drawbacks, and an outline of future trends in the analysis of organic contaminants in food.
Use of automated direct sample introduction with analyte protectants in the GC–MS analysis of pesticide residues
Authors: Čajka Tomáš , Maštovská Kateřina , Lehotay Steven J. , Hajšlová Jana
Published: June 2005

Automated large‐volume direct sample introduction, or difficult matrix introduction (DMI), was investigated in the determination of 44 pesticide residues possessing a wide range of physico‐chemical properties (volatility, polarity, pKa) in fruit‐based baby food by means of gas chromatography–mass spectrometry (GC–MS) with a quadrupole mass analyzer. DMI has advantages over traditional injection because large volumes (up to 30 μL) of potentially dirty sample extracts can be injected into the GC–MS, but nonvolatile matrix components that would normally contaminate the inlet are removed after every injection. The extra matrix and glass surfaces involved in DMI, however, make the system more prone to the matrix‐induced chromatographic enhancement effect, which adversely affects quantification of several pesticides. To overcome this problem, matrix‐matched calibration standards and/or the use of analyte protectants were applied in the DMI approach, and the analysis of extracts was also compared before and after undergoing clean‐up by dispersive solid‐phase extraction. For best quantification, clean‐up was still needed, and the combination of matrix‐matching with analyte protectants gave the most reproducible results. Depending on the application, however, the addition of analyte protectants (a mixture of 3‐ethoxy‐1,2‐propanediol, L‐gulonic acid 3‐lactone, and D‐sorbitol) to sample extracts and calibration standards in solvent (non‐matrix matched), gave satisfactory quantification for most of the 44 pesticides tested. The lowest calibration levels for 34 of the 44 pesticides were ⩽10 ng/g, which meets the standard required by the European Union Baby Food Directive (2003/13/EC).
Induced Circular Dichroism to Optically Active Poly{[methyl(1‐naphthyl)silylene](o‐phenylene)methylene}s Assisted by Supramolecular Complexation with β‐Cyclodextrin
Authors: Park Sung Young , Uenishi Kazuya , Kawakami Yusuke
Published: June 2005

Summary: Optically active poly{methyl(1‐naphthyl)silylene](o‐phenylene)methylene}s with different molecular weights and configurations were prepared, and their supramolecular complexes with β‐cyclodextrin were investigated in a water–tetrahydrofuran mixture (1:1 v/v) at the temperatures between 25 and 68 °C. Complexation was very sensitive to sample preparation, molecular weight of the polymer as well as the configuration of the chiral silicon center. Supramolecular complexation, followed by changes in the circular dichroism, took place enantioselectively and the complex of the high‐molecular weight (+)‐polycarbosilane with β‐cyclodextrin exhibited a dramatic change in its induced circular dichroism. The mechanism of this unique complexation was investigated by SEC, 1H NMR spectroscopy, UV, fluorescence, and circular dichroism.

Supramolecular complexation of β‐cyclodextrin with the optically active and isotactic polymer.

magnified image

Supramolecular complexation of β‐cyclodextrin with the optically active and isotactic polymer.
Cover Picture: Macromol. Rapid Commun. 12/2005
Authors: Malinova Violeta , Rieger Bernhard
Published: June 2005

Cover: The palladium‐catalyzed coordination polymerization of carbon monoxide and bioactive monomers was explored as a tool to produce biofunctionalized polyketones for first time. The method allows control of the molecular weight, chain length and the amphiphilic nature of the polymer architectures. Further details can be found in the Communication by V. Malinova and B. Rieger* on page 945.
Meige syndrome and pallidal deep brain stimulation
Authors: Houser Melissa , Waltz Thomas
Published: June 2005

The cause of primary Meige syndrome is unknown, and although gender and age predilections are different from idiopathic torsion dystonia, most investigators consider Meige syndrome a variant of that disorder. Interest in the use of stereotactic brain surgery for refractory forms of dystonia is thus increasing. There is little experience with the use of deep brain stimulation (DBS) in focal dystonias, and reports of its use in Meige syndrome are very rare. We report on a case of Meige syndrome successfully treated with bilateral pallidal DBS. © 2005 Movement Disorder Society
Efficacy and safety of repeated doses of botulinum toxin type B in type A resistant and responsive cervical dystonia
Authors: Factor Stewart A. , Molho Eric S. , Evans Sharon , Feustel Paul J.
Published: June 2005

Efficacy of botulinum toxin type B (BoNT B) for the treatment of type A‐resistant (AR) and non‐A‐resistant (NAR) cervical dystonia (CD) has been demonstrated in several single injection studies. There is little data available on long‐term therapy with repeated injection sessions and it is unknown if AR and NAR patients respond in a similar manner over time. To evaluate the long‐term efficacy and safety of BoNT B in AR and NAR CD patients, we carried out a prospective, open‐label study examining 10 repeated dosing sessions of BoNT B in 34 patients with CD (15 AR and 19 NAR). Dosing was started at 10,000 units and could be increased to 25,000. Assessments included the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) and a patient global assessment at each baseline (injection) and Week 4 (peak effect) visit. Change in TWSTRS total was the primary efficacy end point. Data was analyzed using repeated‐measures analysis of variance. BoNT B therapy resulted in an overall significant improvement of CD (P < 0.001) and improvement was seen in all 10 individual sessions (2.5 years). The magnitude of response decayed over time (P < 0.001). There was no difference between AR and NAR patients with regard to dose, treatment effect, or decay in response. The AR group perceived (patient global) treatment as being less effective (P = 0.047). Dry mouth frequency decreased with each session despite increasing doses whereas flu‐like syndrome and weakness increased. BoNT B therapy provides long‐term benefit for CD patients but the magnitude of response diminishes over time. The cause of this decay is probably multifactorial. AR and NAR CD patients respond in a similar fashion. © 2005 Movement Disorder Society
Open‐label pilot study of levetiracetam (Keppra) for the treatment of levodopa‐induced dyskinesias in Parkinson's disease
Authors: Zesiewicz Theresa A. , Sullivan Kelly L. , Maldonado John L. , Tatum William O. , Hauser Robert A.
Published: June 2005

We evaluated the tolerability and preliminary efficacy of levetiracetam (LEV; Keppra) in reducing levodopa‐induced dyskinesias in Parkinson's disease (PD) in an open‐label pilot study. Nine PD patients who were experiencing peak‐dose dyskinesias for at least 25% of the awake day and were at least moderately disabling were treated with LEV in doses up to 3,000 mg for up to 60 days. The primary outcome measure was the percent of the awake day that patients spent on without dyskinesia or with nontroublesome dyskinesia (good on time). The mean dose of LEV at endpoint was 625 ± 277 mg/day. LEV significantly improved percent of the awake day on without dyskinesia or with nontroublesome dyskinesia at endpoint compared to baseline (43% ± 12% vs. 61% ± 17%; P = 0.02). Percent on time with troublesome dyskinesia decreased from 23% ± 10% at baseline to 11% ± 6% at endpoint, although not significantly. There was no significant increase in off time from baseline to endpoint. There was a 56% dropout rate, mostly due to somnolence. In PD patients who experienced peak‐dose dyskinesia for at least 25% of the awake day, LEV significantly improved on time without dyskinesia or with nontroublesome dyskinesia. © 2005 Movement Disorder Society
Frequency of movement disorders in an Ethiopian university practice
Authors: Bower James H. , Teshome Mesfin , Melaku Zenebe , Zenebe Guta
Published: June 2005

There is little information on the frequency of movement disorders seen by physicians in the continent of Africa. We performed a medical record review of all patients seen in a university‐based neurology clinic in Addis Ababa, Ethiopia, over 1 year to determine the frequency of movement disorders seen, disease characteristics, diagnostic evaluations, and treatment. A total of 15.1% of the neurological patients were seen for movement disorders. Of these, most were for parkinsonism (47.7%), followed by ataxia (16.5%), dystonia (8.3%), essential tremor (8.3%), chorea (7.3%), and miscellaneous (11.9%). Diagnostic evaluations were limited, but treatment was available, although expensive. In spite of the limitations, patients with movement disorders require and seek care in Ethiopia in proportions comparable to developed nations. This finding underlines the need for adequate training in movement disorders for physicians and neurologists in Africa. © 2005 Movement Disorder Society
Effect of kynurenine 3‐hydroxylase inhibition on the dyskinetic and antiparkinsonian responses to levodopa in parkinsonian monkeys
Authors: Samadi Pershia , Grégoire Laurent , Rassoulpour Arash , Guidetti Paolo , Izzo Emanuela , Schwarcz Robert , Bédard Paul J.
Published: June 2005

Homeostatic interactions between dopamine and glutamate are central to the normal physiology of the basal ganglia. This relationship is altered in Parkinsonism and in levodopa‐induced dyskinesias (LID), resulting in an upregulation of corticostriatal glutamatergic function. Kynurenic acid (KYNA), a tryptophan metabolite with antagonist activity at ionotropic glutamate receptors and the capability to inhibit glutamate release presynaptically, might therefore be of therapeutic value in LID. To evaluate this hypothesis, we used a pharmacological tool, the kynurenine 3‐hydroxylase inhibitor Ro 61‐8048, which raises KYNA levels acutely. Ro 61‐8048 was tested in MPTP cynomolgus monkeys with a stable parkinsonian syndrome and reproducible dyskinesias after each dose of levodopa. Serum and CSF concentrations of KYNA and its precursor kynurenine increased dose‐dependently after Ro 61‐8048 administration, alone or in combination with levodopa. Coadministration of Ro 61‐8048 with levodopa produced a moderate but significant reduction in the severity of dyskinesias while maintaining the motor benefit. These results suggest that elevation of KYNA levels through inhibition of kynurenine 3‐hydroxylase constitutes a promising novel approach for managing LID in Parkinson's disease. © 2005 Movement Disorder Society
PIFA loaded with artificial magnetic material: Practical example for two utilization strategies
Authors: Ikonen Pekka , Maslovski Stanislav , Tretyakov Sergei
Published: June 2005

In this paper, we experimentally investigate the effect of artificial magnetic material loading on the radiation properties of a planar inverted F‐antenna (PIFA). We introduce two principal strategies for the utilization of the magnetic material with planar antennas. It is shown that a dramatic bandwidth enhancement is achievable when the material is utilized in its resonant regime. In addition, it is experimentally proven that at frequencies below the material resonance, the load can be considered as a paramagnetic material, thus enabling efficient size miniaturization. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 205–210, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20946
Band selection in an amplified spontaneous emission source using the backward‐feedback technique
Authors: Sinivasagam V. , Dimyati K. , Singh R. D. , Abushagur M. A. G.
Published: June 2005

In this paper, the band‐selective behavior in an amplified spontaneous emission (ASE) source of an erbium‐doped silica fiber (EDF) is demonstrated. C‐band operation is obtained without backward ASE feedback, whereas L‐band operation is obtained with backward ASE feedback. The conversion from C‐band to L‐band results in a total spectral power improvement of 0.3 dB, while the 980‐nm pump power is fixed at 44.5 mW. The average power‐density improvement for the L‐band region (1565–1605 nm) was 18.9 dB with a maximum of 33.8 dB at 1565.0 nm, compared to the feedback and nonfeedback systems. The maximum power‐density results for the feedback and nonfeedback systems are −10.4 and −4.0 dBm at 1559.4 and 1563.4 nm, respectively. A bandwidth of 85.6 nm (1515.4–1601.0 nm) and 67.3 nm (1545.2–1612.5 nm) was obtained for the feedback and nonfeedback systems, respectively, at a power density of −30 dBm/nm. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 218–220, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20949
Investigation of the mutual effect between human head and new shapes of PIFAs used in mobile communication systems
Authors: Nashaat Dalia , Alsadek Hala , Ghali Hani
Published: June 2005

This paper studies the influence of the close proximity between the human head and various planar inverted‐F antennas (PIFAs) used for portable handsets. The effects of the head on the antenna characteristics are investigated. The results for three selected antenna shapes are illustrated. The simulations are done using an HFSS head phantom with a PIFA in the same radiation box. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 243–248, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20957
Dielectric electromagnetic band gap design with genetic algorithm
Authors: Rajo‐Iglesias Eva , Sanabria‐Martínez Patricia , Fernández‐Villacañas José‐Luis
Published: June 2005

Periodic dielectric structures have been used for a widespread of microwave applications. In this work, a developed software to design 2D dielectric electromagnetic band gap (EBG) structures is presented. By selecting the stop‐band properties of bandwidth and central frequency, the software provides the materials and dimensions for an optimized design. A special genetic algorithm (GA) has been used as an optimization procedure. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 248–252, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20958
Accuracy investigation of the wire‐grid model in EM scattering analysis with the MoM
Authors: Yuan Weiliang , Li Erping
Published: June 2005

This paper investigates a wire‐grid model for the scattering analysis of bodies using the method of moments (MoM). The accuracy of the model is explored in terms of basis functions, and the size and radius of the segments of the model are determined through a defined error function. The numerical simulations indicate that the wire‐grid model can accurately calculate the scattering problems when the proper model and the triangular basis function in the MoM are used. The optimal radius of the segments in the model is determined. However, the MoM with the sinusoidal basis function used in NEC2 results in very high error if both large size and large radius are adopted for the segments. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 259–263, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20960
Chromatic dispersion measurement using the relative power of two beating frequencies
Authors: Al‐Qdah M. T. , Rashid H. A. , Khazani M. , Dimyati K. , Ali B. M.
Published: June 2005

A novel technique for measuring the accumulated chromatic dispersion (CD) in single‐mode fiber (SMF) is presented. The technique measures CD by simultaneously launching pump and probe optical signals at ω1 angular optical‐frequency separation, and two phase‐conjugated terms into the SMF. The relative power of the beat frequencies that appear after the photodetector at ω1 and at 2ω1 is used to determine the net dispersion. This technique was successfully demonstrated using a semiconductor optical amplifier (SOA) as a phase conjugator in order to achieve a 20‐dB relative power variation as a result of up to 1900‐ps/nm CD change. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 268–271, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20962
Analysis of the modal characteristics of a Bragg fiber with a small number of claddings using a very simple analytical approach
Authors: Singh Vivek , Prasad B. , Ojha S. P.
Published: June 2005

In this paper, we reexamine the well‐known Bragg fibers from a very simple, analytical point of view. It is found that with a very small number of cladding regions one can obtain modal characteristics of Bragg fibers which are similar to those of the step‐index standard fiber under the weak‐guidance condition. The Bragg fibers are therefore close competitors of the standard weakly‐guiding step‐index fiber with respect to the few mode‐guidance properties, apart from low absorption. We show this for some special cases by obtaining the dispersion curves. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 271–275, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20963
Ultra wide band pass filters (UWBPF) based on complementary split rings resonators
Authors: Bonache J. , Martín F. , García‐García J. , Gil I. , Marqués R. , Sorolla M.
Published: June 2005

In this work, a new strategy for the design of microstrip filters with ultra‐wide bandwidths is proposed. This is based on the combination of square‐shaped complementary split‐ring resonators (CSRRs) etched in the ground plane and grounded stubs. Coupling between adjacent resonators is achieved by means of λ/4 lines, acting as impedance inverters. To illustrate the potentiality of the approach, a prototype device with 90% fractional bandwidth has been designed for operation at C‐band. The measured fractional bandwidth (87%), in‐band losses (<1.3 dB), and out‐of‐band rejection (>30 dB), obtained on a device scaled down in frequency, point out the high performance achievable with this design methodology. Moreover, the first frequency parasitic (spurious) does not appear up to three times the central filter frequency. Due to the small dimensions, wide bandwidths, and compatibility with planar circuit technology, it is believed that the approach presented in this work can be of actual interest to the design of filters for ultra‐wideband applications. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 283–286, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20966
Feasibility of a low‐cost hybrid tunable phase shifter based on nonlinear transmission lines
Authors: Jrad Akil , Bourtoutian Raffi , Ferrari Philippe , El Helwani Amer
Published: June 2005

This paper presents the realization of a hybrid tunable phase shifter. The principle advantage of the hybrid approach is the low cost of the varactor diodes. The phase shifter employs a variable‐velocity transmission line obtained by periodically loading a coplanar waveguide (CPW) with the varactors. The designed phase shifter is able to produce a variable phase shift from 0° to 180° at 3.8 GHz with a maximum insertion loss of 4 dB. The return loss is better than −10 dB over all the phase states. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 286–289, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20967
On the design model of broadside‐coupled SSS line for microwave integrated circuits
Authors: Kumar Raj
Published: June 2005

A practical design model for the analysis of broadside‐coupled suspended‐substrate stripline is presented. The modified design expression of the shielded microstrip line is valid for a wide range of structural parameters and dielectric constants, that is,1.0≤ εr≤140.0for dielectric constant,0.1≤ w/h ≤10.0for strip width with an accuracy of <0.5%. This design expression is further extended for broadside‐coupled suspended‐substrate stripline. The proposed broadside‐coupled suspended‐substrate stripline (BCSSS) expressions are valid over a practical range of structural parameters and dielectric constants. The validity range of this expression for structural parameters is1.0≤ εr≤16.0for dielectric constant,0.1≤ w/b ≤2.0for strip width, and s/b ≤0.5for substrate thickness. The average accuracy of the present expressions is <0.6% and <0.2% for the even‐ and odd‐mode effective dielectric constants, respectively, with maximum deviation less than 1.16% with respect to reference value. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 292–297, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20969
Coordinated scheduling of customer orders for quick response
Authors: Ahmadi Reza , Bagchi Uttarayan , Roemer Thomas A.
Published: June 2005

The scheduling problem addressed in this paper concerns a manufacturer who produces a variety of product types and operates in a make‐to‐order environment. Each customer order consists of known quantities of the different product types, and must be delivered as a single shipment. Periodically the manufacturer schedules the accumulated and unscheduled customer orders. Instances of this problem occur across industries in manufacturing as well as in service environments. In this paper we show that the problem of minimizing the weighted sum of customer order delivery times is unary NP‐hard. We characterize the optimal schedule, solve several special cases of the problem, derive tight lower bounds, and propose several heuristic solutions. We report the results of a set of computational experiments to evaluate the lower bounding procedures and the heuristics, and to determine optimal solutions. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005.
A dynamic allocation heuristic for centralized safety stock
Authors: Cao De‐bi , Silver Edward A.
Published: June 2005

An inventory system that consists of a depot (central warehouse) and retailers (regional warehouses) is considered. The system is replenished regularly on a fixed cycle by an outside supplier. Most of the stock is direct shipped to the retailer locations but some stock is sent to the central warehouse. At the beginning of any one of the periods during the cycle, the central stock can then be completely allocated out to the retailers. In this paper we propose a heuristic method to dynamically (as retailer inventory levels change with time) determine the appropriate period in which to do the allocation. As the optimal method is not tractable, the heuristic's performance is compared against two other approaches. One presets the allocation period, while the other provides a lower bound on the expected shortages of the optimal solution, obtained by assuming that we know ahead of time all of the demands, period by period, in the cycle. The results from extensive simulation experiments show that the dynamic heuristic significantly outperforms the “preset” approach and its performance is reasonably close to the lower bound. Moreover, the logic of the heuristic is appealing and the calculations, associated with using it, are easy to carry out. Sensitivities to various system parameters (such as the safety factor, coefficient of variation of demand, number of regional warehouses, external lead time, and the cycle length) are presented. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005.
Design of Survivable Networks: A survey
Authors: Kerivin Hervé , Mahjoub A. Ridha
Published: June 2005

For the past few decades, combinatorial optimization techniques have been shown to be powerful tools for formulating and solving optimization problems arising from practical situations. In particular, many network design problems have been formulated as combinatorial optimization problems. With the advances of optical technologies and the explosive growth of the Internet, telecommunication networks have seen an important evolution and therefore designing survivable networks has become a major objective for telecommunication operators. Over the past years, much research has been carried out to devise efficient methods for survivable network models, and particularly cutting plane based algorithms. In this paper, we attempt to survey some of these models and the optimization methods used for solving them. © 2005 Wiley Periodicals, Inc. NETWORKS, Vol. 46(1), 1–21 2005
Change of basis in polynomial interpolation
Authors: Gander W.
Published: June 2005

Several representations for the interpolating polynomial exist: Lagrange, Newton, orthogonal polynomials, etc. Each representation is characterized by some basis functions. In this paper we investigate the transformations between the basis functions which map a specific representation to another. We show that for this purpose the LU‐ and the QR‐decomposition of the Vandermonde matrix play a crucial role. Copyright © 2005 John Wiley & Sons, Ltd.
Splitting iterations for circulant‐plus‐diagonal systems
Authors: Ho Man‐Kiu , Ng Michael K.
Published: June 2005

We consider the system of linear equations (C + iD)x=b, where C is a circulant matrix and D is a real diagonal matrix. We study the technique for constructing the normal/skew‐Hermitian splitting for such coefficient matrices. Theoretical results show that if the eigenvalues of C have positive real part, the splitting method converges to the exact solution of the system of linear equations. When the eigenvalues of C have non‐negative real part, the convergence conditions are also given. We present a successive overrelaxation acceleration scheme for the proposed splitting iteration. Numerical examples are given to illustrate the effectiveness of the method. Copyright © 2005 John Wiley & Sons, Ltd.
Exponential data fitting using multilinear algebra: the single‐channel and multi‐channel case
Authors: Papy J. M. , De Lathauwer L. , Van Huffel S.
Published: June 2005

There is a wide variety of signal processing applications in which the data are assumed to be modelled as a sum of exponentially damped sinusoids. Many subspace‐based approaches (such as ESPRIT, matrix pencil, Prony, etc.) aim to estimate the parameters of this model. Typically, the data are arranged in Toeplitz or Hankel matrices and suitable parameter estimates are obtained via a truncated singular value decomposition (SVD) of the data matrix. It is shown that the parameter accuracy may be improved by arranging single‐channel or multi‐channel data in a higher‐order tensor and estimating the model parameters via a multilinear generalization of the SVD. The algorithm is presented and its performance is illustrated by means of simulations. Copyright © 2005 John Wiley & Sons, Ltd.
A novel bithiazole‐containing polymeric complex with soft ferromagnetism
Authors: Jiang Liming , Sun Weilin
Published: June 2005

A novel polymer resulting from the polycondensation of 2,2′‐diamino‐4,4′‐bithiazole (DABT) with 5,5′‐methylene‐bis‐salicylaldehyde (MBSA) and its ferric complex are described. Analyses of Fourier transform infrared (FT‐IR) and X‐ray photoelectron spectroscopy (XPS) revealed that both bithiazole residue and Schiff‐base moiety acted as coordination sites for Fe3+ ions in the polymeric matrix. The magnetic behavior of the complex was studied as a function of magnetic field strength (0–60 kOe) at 25 K and as a function of temperature (5–300 K) at a magnetic field strength of 30 kOe. The hysteretic loop was measured at 5 K for the complex showing coercivity (Hc) of 20 Oe and remnant magnetization (Mr) of 0.002 emu/g, which is much lower than those of bithiazole‐based polymeric complexes previously reported. The results indicated that the present complex is of the typical characteristics of a soft ferromagnet. Copyright © 2005 John Wiley & Sons, Ltd.