bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of change in CNS involvement in neuropsychiatric SLE: A magnetization transfer study
Authors: Emmer Bart J. , Steens Stefan C.A. , Steup‐Beekman Gerda M. , van der Grond J. , Admiraal‐Behloul Faiza , Olofsen Hans , Bosma Gerlof P.Th. , Ouwendijk Wiljan J.N. , Huizinga Tom W.J. , van Buchem Mark A.
Published: August 2006

Purpose

To assess whether magnetization transfer imaging (MTI) parameters change in correspondence with clinical changes in NPSLE patients.

Materials and Methods

Nineteen female patients (mean age = 37.5 years, range = 19–64) underwent MTI on at least two separate occasions (mean time between scans = 25.4 months, range = 5.4–52.3 months). Twenty‐four pairs of scans of 19 patients were available. Each patient's clinical course was classified as improved, stable, or deteriorated. Whole‐brain magnetization transfer ratio (MTR) histograms were generated. The peak height of these histograms was used as an estimate of parenchymal integrity. Based on the change in clinical status, paired examinations were grouped and tested for significant differences between the first and second examinations using paired‐samples t‐tests.

Results

Four patients clinically deteriorated, all patients showed a significant peak height decrease (mean decrease = 8.6%, P = 0.02), and in 14 patients with stable disease the peak height did not change significantly (mean increase = 0.4%). Six patients clinically improved, and all showed a significant relative peak height increase (mean increase = 12.0%, P = 0.02).

Conclusion

The peak height of whole‐brain MTR histograms corresponds to changes in the clinical status of individual NPSLE patients. This suggests that MTI can be a valuable tool in the clinical assessment of such patients. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Human embryonic stem cell‐derived neural precursors develop into neurons and integrate into the host brain
Authors: Guillaume Daniel J. , Johnson M. Austin , Li Xue‐Jun , Zhang Su‐Chun
Published: August 2006

Whether and how in‐vitro‐produced human neural precursors mature and integrate into the brain are crucial to the utility of human embryonic stem (hES) cells in treating neurological disorders. After transplantation into the ventricles of neonatal immune‐deficient mice, hES‐cell‐derived neural precursors stopped expressing the cell division marker Ki67, except in neurogenic areas, and differentiated into neurons and then glia in a temporal course intrinsic to that of human cells regardless of location. The human cells located in the gray matter became neurons in the olfactory bulb and striatum, whereas those in the white matter produced exclusively glia. Importantly, the grafted human cells formed synapses. Thus, the in‐vitro‐produced human neural precursors follow their intrinsic temporal program to produce neurons and glia and, in response to environmental signals, generate cells appropriate to their target regions and integrate into the brain. © 2006 Wiley‐Liss, Inc.
Pituitary adenylate cyclase‐activating polypeptide regulates forebrain neural stem cells and neurogenesis in vitro and in vivo
Authors: Ohta Shigeki , Gregg Christopher , Weiss Samuel
Published: August 2006

Recent studies suggest that adult neurogenesis can contribute significantly to recovery from brain damage. As a result, there is strong interest in the field in identifying potentially therapeutic factors capable of promoting increased expansion of endogenous neural stem cell (NSC) populations and increased neurogenesis. In the present study, we have investigated the effects of PACAP on the NSC populations of the embryonic and adult forebrain. Our results demonstrate that the PACAP receptor, PAC1‐R, is expressed by both embryonic and adult NSCs. The activation of PACAP signaling in vitro enhanced NSC proliferation/survival through a protein kinase A (PKA)‐independent mechanism. In contrast, PACAP promoted NSC self‐renewal and neurogenesis through a mechanism dependent on PKA activation. Finally, we determined that the intracerebroventricular infusion of PACAP into the adult forebrain was sufficient to increase neurogenesis significantly in both the hippocampus and the subventricular zone. These results demonstrate PACAP is unique in that it is capable of promoting NSC proliferation/survival, self‐renewal, and neurogenesis and, therefore, may be ideal for promoting the endogenous regeneration of damaged brain tissue. © 2006 Wiley‐Liss, Inc.
Functional magnetic resonance imaging in rodents: Methodology and application to spinal cord injury
Authors: Ramu Jaivijay , Bockhorst Kurt H. , Mogatadakala Kishore V. , Narayana Ponnada A.
Published: August 2006

Functional MRI (fMRI) on spinal cord‐injured rodents at 4 and 8 weeks post injury (PI) is described. The paradigm for fMRI, based on electrical stimulation of rat paws, was automated using an in‐house designed microprocessor‐based controller that was interfaced to a stimulator. The MR images were spatially normalized to the Paxinos and Watson atlas using publicly available digital images of the cryosections. In normal uninjured animals, the activation was confined to the contralateral somatosensory cortex. In contrast, in injured animals, extensive activation, which included structures such as ipsilateral cortex, thalamus, hippocampus, and the caudate putamen, was observed at 4 and 8 weeks PI. Quantitative cluster analysis was carried out to calculate the volumes and centers of activation in individual brain structures. Based on this analysis, significant increase in activation between 4 and 8 weeks was observed only in the ipsilateral caudate putamen and thalamus. These studies suggest extensive and ongoing brain reorganization in spinal cord‐injured animals. © 2006 Wiley‐Liss, Inc.
Fucosyl‐GM1 expression and amyloid‐β protein accumulation in PC12 cells
Authors: Yanagisawa Makoto , Ariga Toshio , Yu Robert K.
Published: August 2006

Gangliosides, sialic acid‐containing glycosphingolipids, are ubiquitously expressed in all eukaryotic cells and are localized primarily in the plasma membrane. For a rat pheochromocytoma cell line, PC12, which has been used frequently as a model for investigating events leading to neuronal differentiation, it is generally thought that GM1 is a major ganglioside, based on reactivity with the probe cholera toxin B subunit (Ctxb). From a series of biochemical studies, however, it has been reported that no GM1 is expressed in PC12 cells. In this study, we have reevaluated GM1 expression and Ctxb reactivity in PC12 cells and a subcloned line, PC12D cells. Flow cytometric analysis with Ctxb revealed that about 30–50% of PC12 cells were reactive with Ctxb. However, a detailed biochemical analysis showed that PC12 cells express abundantly a different ganglioside, fucosyl‐GM1, instead of GM1, and the reactivity of Ctxb in the PC12 cells actually arose from its interaction with fucosyl‐GM1, which also interacts with this ligand. Because it has been claimed that amyloid‐β protein (Aβ) interacts with GM1 in PC12 cells to provide “seeding” for amyloid to accumulate, we further evaluated this possibility and found that Aβ is mostly likely interacting with fucosyl‐GM1 in this cell line. Our data thus suggest that a specific interaction may occur between Aβ and fucosyl‐GM1 for the accumulation of amyloid in PC12 cells. © 2006 Wiley‐Liss, Inc.
Decline of striatal dopamine release in parkin‐deficient mice shown by ex vivo autoradiography
Authors: Sato Shigeto , Chiba Tomoki , Nishiyama Shingo , Kakiuchi Takeharu , Tsukada Hideo , Hatano Taku , Fukuda Takahiro , Yasoshima Yasunobu , Kai Nobuyuki , Kobayashi Kazuto , Mizuno Yoshikuni , Tanaka Keiji , Hattori Nobutaka
Published: August 2006

Parkin is the causal gene of autosomal recessive juvenile parkinsonism (AR‐JP). Dopamine (DA) metabolism has been linked to Parkinson's disease (PD). To understand the pathogenesis of AR‐JP, we generated parkin‐deficient mice to assess the status of DA signaling pathway and examine DA release and DA receptor by ex vivo autoradiography. Ex vivo autoradiography using [11C]raclopride showed a clear decrease in endogenous DA release after methamphetamine challenge in parkin‐deficient mice. Furthermore, parkin deficiency was associated with considerable upregulation of DA (D1 and D2) receptor binding in vivo in the striatum and increased DA levels in the midbrain. Our results suggest that dopaminergic neurons could behave abnormally before neuronal death. © 2006 Wiley‐Liss, Inc.
Altered gene activity correlated with long‐term memory formation of conditioned taste aversion in Lymnaea
Authors: Azami Sachiyo , Wagatsuma Akiko , Sadamoto Hisayo , Hatakeyama Dai , Usami Takeshi , Fujie Manabu , Koyanagi Ryo , Azumi Kaoru , Fujito Yutaka , Lukowiak Ken , Ito Etsuro
Published: August 2006

The pond snail Lymnaea stagnalis is capable of learning conditioned taste aversion (CTA) and then consolidating that learning into long‐term memory (LTM) that persists for at least 1 month. LTM requires de novo protein synthesis and altered gene activity. Changes in gene activity in Lymnaea that are correlated with, much less causative, memory formation have not yet been identified. As a first step toward rectifying this situation, we constructed a cDNA microarray with mRNAs extracted from the central nervous system (CNS) of Lymnaea. We then, using this microarray assay, identified genes whose activity either increased or decreased following CTA memory consolidation. We also identified genes whose expression levels were altered after inhibition of the cyclic AMP response element‐binding protein (CREB) that is hypothesized to be a key transcription factor for CTA memory. We found that the molluscan insulin‐related peptide II (MIP II) was up‐regulated during CTA‐LTM, whereas the gene encoding pedal peptide preprohormone (Pep) was down‐regulated by CREB2 RNA interference. We next examined mRNAs of MIP II and Pep using real‐time RT‐PCR with SYBR Green. The MIP II mRNA level in the CNS of snails exhibiting “good” memory for CTA was confirmed to be significantly higher than that from the CNS of snails exhibiting “poor” memory. In contrast, there was no significant difference in expression levels of the Pep mRNA between “good” and “poor” performers. These data suggest that in Lymnaea MIP II may play a role in the consolidation process that forms LTM following CTA training. © 2006 Wiley‐Liss, Inc.
Raman spectra of apatites: La10−x Si6−y (Al,Fe)y O26±δ
Authors: Lucazeau G. , Sergent N. , Pagnier T. , Shaula A. , Kharton V. , Marques F. M. B.
Published: August 2006

Raman spectra of eight polycrystalline apatites of the general formula La10−xSi6−yM′yO26 ± δ with M′ = Al or Fe were obtained at 300 K. Raman spectra of La10Si4Fe2O26 and La9.83Si4.5Al1.5O26 were investigated in the range 80–1000 K and 80–623 K, respectively. Tentative assignments of bands to stretching and bending modes of SiO4 tetrahedra and to M'O vibrations are proposed. Except for the two new bands, which appear around 700 cm−1 when Al is replaced by Fe, only some band broadenings and relative intensity changes are observed as a function of the rate of O5 or La vacancies. Most of the bands soften and broaden continuously when raising the temperature. This is an indication that the Al‐ and Fe‐substituted apatites do not undergo any structural change up to 1000 K. Above 1000 K, the broad and weak shoulder observed at 850 cm−1 for La10Si4Fe2O26 is replaced by a strong band at 868 cm−1, suggesting that SiO4 tetrahedra undergo a structural modification. All compounds show the same residual band broadening at 80 K. This suggests that there is a small rate of static disorder preferentially related to the solubility of Al and Fe in the Si sublattice rather than to other defects. Moreover, the observation of FeO modes indicates that the dynamics of the solid solution obeys the so‐called two‐mode behavior. The occurrence of FeO stretching vibrations 150 cm−1 lower than for those of SiO suggests that the coordination number of iron could be larger than 4, particularly for the Fe4+ species. Copyright © 2006 John Wiley & Sons, Ltd.
On the use of conducting polymers to improve the resistance against corrosion of paints based on polyurethane resins
Authors: Iribarren J. I. , Armelin E. , Liesa F. , Casanovas J. , Alemán C.
Published: August 2006

This work analyzes the physical properties of several paints and the resistance against corrosion that they impart after being modified by adding a conducting polymer. Five different formulations were selected: four polyurethane resins (two varnish and two aqueous based) and one multicomponent system containing polyester, melamine and cellulose acetobutyrate. The physical properties of the coatings were examined by FTIR, thermal analyses and viscosity measurements. Corrosion resistance of carbon steel coated with these paints was studied by means of accelerated laboratory tests. The results provided by the original formulations and those modified by adding 1 % w/w of polypyrrole or poly(3‐decylthiophene‐2,5‐diyl) regioregular were compared. Although the general behavior was irregular, showing dependence with the paint formulation, excellent results were achieved for an aqueous based polyurethane resin modified with polypyrrole. Accelerated immersion experiments in salt and acid solutions showed fast degradation of the film without conducting polymer, while the polymeric film with polypyrrole offered a higher resistance.
An EIS study of the effect of the pedant group in imidazolines as corrosion inhibitors for carbon steel in CO2 environments
Authors: Villamizar W. , Casales M. , Gonzales‐Rodriguez J. G. , Martinez L.
Published: August 2006

Electrochemical impedance spectroscopy (EIS) measurements were carried out to study the corrosion inhibition of carbon steel in 3 % NaCl with and without diesel saturated with CO2 at 50 °C. The inhibitors examined were hydroxyethyl (HEI‐18), amino ethyl (AEI‐18), and amide ethyl imidazolines (AMEI‐18). When the oily phase, i.e diesel, is absent, the inhibition efficiency of the imidazolines is low, around 80 %. It was found, however, that the inhibition dramatically increased with the presence of the oily phase, because the imidazolines are able to act as both emulsifiers and corrosion inhibitors. Experimental results showed an increase in the film resistance (Rf), charge transfer resistance (Rct), capacitance of the film and the capacitance of the double layer values with the addition of inhibitor in presence of the oily phase also in several orders of magnitude. The most effective inhibitor in presence of diesel is a solution of AMEI‐18, as the oily phase is carried to the surface also. This is due to the presence of two large alkyl groups than the only chain present in the HEI‐18 and AEI‐18 imidazolines with better hydrophobic properties associated with the formation of a protective film that reduces drastically the corrosion process. The effects of the interaction of inhibitors with hydrocarbons and the correlation on the performance of inhibitor films have been examined.
Microbiological influence on the electro‐chemical potential of stainless steel
Authors: Gümpel P. , Arlt N. , Telegdi J. , Schiller D. , Moos O.
Published: August 2006

The microbiologically caused ennoblement appears in natural water on all stainless steels equally and can only be prevented by the use of biocides. Temperature and supply of nutrients have an influence on the increasing rate of the potential, as well as the presence of manganese ions in the water favors the potential rise. The final value of the potential is substantially regulated by the biological system and is independent of the steel composition. An endangerment of stainless steels by a selective corrosion attack e.g. pitting corrosion arises if the critical repassivation potential of the steel lies below the open‐circuit potential appearing in the natural system. This can be due to the alloy composition or due to process‐conditioned weakening of the passive layer, for example by annealing colors on and beside welded joints.
Single‐Step Magnetic Patterning of Iron Nanoparticles in a Semiconducting Polymer Matrix
Authors: Kumar Jitendra , Singh Rajiv K. , Samanta Satya B. , Rastogi Ramesh C. , Singh Ramadhar
Published: August 2006

Summary: A cost‐effective chemical synthesis and single‐step magnetic patterning of iron nanoparticles (size ≈100 nm) in a semiconducting P3OT polymer matrix is reported wherein Fe nanostructures (≈150 ± 50 nm) are periodically aligned with π‐conjugated P3OT chains to form a nanomagnet‐semiconductor‐nanomagnet (Fe‐π‐Fe) structure. The resultant periodic patterning has been characterized by XRD, SEM and AFM techniques and is attributed to the intrinsic alignment of Fe at the nanometer‐scale level in a conjugated polymer matrix under the influence of a magnetic field. Such a P3OT/Fe matrix may find application in magnetic memory devices.

AFM image in nanometers showing the periodic nanostructuring of P3OT‐Fe matrices when the P3OT‐Fe nanocomposite films were grown under an applied magnetic field.

image

AFM image in nanometers showing the periodic nanostructuring of P3OT‐Fe matrices when the P3OT‐Fe nanocomposite films were grown under an applied magnetic field.
A small bandstop microstrip filter for UWB applications
Authors: Hong Seokjin , Lee Heejun , Park Hoon , Choi Jaehoon
Published: August 2006

A small bandstop microstrip filter for ultra‐wideband application is proposed. The proposed filter combines the traditional short‐circuited stub highpass filter and the open‐circuited stub bandstop filter on the mitered 50‐Ω microstrip line. The distributed highpass filter scheme is applied to achieve highpass filtering characteristics over ultra‐wideband frequency band (3.1–10.6 GHz) and the open‐circuited stubs are used to obtain the band rejection function at Wireless Local Area Network frequency band. The measured results show that the proposed filter has a wide passband characteristic of 132.12% (2.16–10.57 GHz), with the return loss of less than −10 dB and 3‐dB stop band of 14.37% (5.17–5.97 GHz). The measured group delay is less than 0.65 ns within the passband except the rejection band. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2162–2165, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21887
Optimization of chromatic dispersion measurement technique using relative power of two beating frequencies
Authors: Abdul‐Rashid H. A. , Al‐Qdah M. T. , Chuah H. T. , Tayahi M. , Abdullah M. K.
Published: August 2006

Optimization study of the Chromatic Dispersion measurement technique using relative power of two beating frequencies is presented in this paper. The performance of the CD measurement technique is studied in terms of the measurement range and sensitivity as the wavelength separation is varied. Based on the mathematical model and experimental results the technique sensitivity increases with wavelength separation. However, this increase in sensitivity is traded off with narrower measurement range. The measurement technique is optimized at 5.0 GHz wavelength separation with sensitivity of 0.009 (dB/ps/nm) and measurement range of 2500 (ps/nm). © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2154–2156, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21893
A 3D hybrid implicit‐explicit FDTD scheme with weakly conditional stability
Authors: Chen Juan , Wang Jianguo
Published: August 2006

In this paper, the hybrid implicit–explicit finite‐difference time‐domain (HIE‐FDTD) algorithm for a two‐dimensional (2D) TE wave is extended to a full three‐dimensional (3D) wave. The weakly conditional stability is verified by numerical simulation results. Numerical formulations of the 3D HIE‐FDTD method are presented and simulation results are compared to those using the conventional 3D finite‐difference time‐domain method. High computation efficiency is obtained by introducing an unequal space increment in different dimensions in the HIE‐FDTD method. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2291–2294, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21898
An efficient neural network model for the input resonant resistance of coaxial fed rectangular microstrip antennas with thin and thick substrates
Authors: Şimşek Serkan
Published: August 2006

In this paper, an efficient neural network model is suggested to determine the input resonant resistance of coaxial fed rectangular microstrip antennas (MSAs) with thin and thick substrates. The NN results are in good agreement with experimental results reported in literature. This method can easily be modified to address problems involving more general types of MSAs. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2197–2199, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21908
Modeling and application of stepped impedance resonators with double coaxial structure
Authors: Song Kaijun , Fan Yong , Zhang Yonghong
Published: August 2006

An improved accurate modeling for miniaturized stepped impedance resonators with a double coaxial structure is proposed in this paper. The step discontinuities of the double coaxial stepped impedance resonators (DC‐SIRs) have been given full consideration in the modeling. The band‐pass filters have been designed using the accurate modeling of DC‐SIRs. The band‐pass filters mentioned in this paper show excellent performances such as more compact size and lower insertion loss, and it can be used at lower frequencies. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2314–2317, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21910
The multilayer folded couplers and their application
Authors: Chiu L. , Xue Q. , Chan C. H.
Published: August 2006

In this paper, three folded couplers and their application have been presented. The Wilkinson power divider, and 90° and 180° hybrids are folded for size reduction in the multilayered printed circuit media. The folded hybrid ring is employed as the transition between the microstrip line (MSL) and the parallel‐strip line (PSL) for balanced circuit applications. The PSL has an inherent advantage of easy realization of balanced configuration, which is suitable for push–pull designs, especially for high power applications. The PSL makes the design of circuits more flexible than MSL because the lump components and solid state devices can be easily mounted in both series and shunt manners without any difficulties in fabrication. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2285–2288, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21913
Self‐pulsing dynamics of high‐power Yb‐doped fiber lasers
Authors: Fu Shenggui , Feng Xinhuan , Si Libin , Guo Zhancheng , Jia Xiujie , Zhao Ying , Yuan Shuzhong , Dong Xiaoyi
Published: August 2006

Experimental study of self‐pulsing behaviors of Yb‐doped double‐clad fiber lasers is presented. The behavior can be explained by the saturation phenomenon of the unpumped doped fiber. Results from frequency beating of horizontal modes, the pulse curves show fast oscillations in multimode fiber laser. The self‐modulation pulses are restrained in single‐mode fiber lasers, and the pulse train is rather regular and smooth than that of multimode fiber lasers. When the doped fiber is sufficiently pumped, the laser obtained a quasi‐CW output state. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2282–2285, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21914
A continuously steerable array antenna using movable dielectric slabs on a coplanar waveguide
Authors: Cha Junho , Kuga Yasuo , Lee Sangil
Published: August 2006

A simple steerable array antenna is designed using a movable dielectric phase shifter. The change of the effective dielectric constant at different dielectric slab positions on a coplanar waveguide is used as the phase shifter. The impedance matching and desired phase shift conditions are satisfied at two slab heights, and reflection is designed to be minimized at all slab positions. A four‐element steerable array antenna at 5.8 GHz is fabricated and measured for testing purposes. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2222–2227, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21920
TE‐pass Zn‐diffused LiNbO3 waveguide polarizer
Authors: Twu Ruey‐Ching , Huang Chia‐Chih , Wang Way‐Seen
Published: August 2006

Process‐dependence characteristics of Zn‐diffused waveguides on a y‐cut, x‐propagation LiNbO3 substrate at 1.55‐μm wavelength are presented for the first time. The experimental results show that a single‐mode waveguide of extraordinary polarization is easily fabricated and can serve as an effective TE‐pass waveguide polarizer. The best polarization extinction ratio of 32 dB/cm and the corresponding propagation loss of 0.9 dB/cm are obtained. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2312–2314, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21923
Efficiency measurement of antennas for on‐body communications
Authors: Salim Tareq , Hall Peter. S.
Published: August 2006

The Wheeler cap method is used to measure the efficiency of antennas for use in on‐body communication systems. A monopole and a planar inverted F antenna on small ground planes were mounted in contact with body phantom material and their efficiency measured using the Wheeler cap and by a conventional anechoic chamber method. Results from the two methods show close agreement and also are close to results of simulations using commercial software. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2256–2259, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21930
A 2.4‐GHz dual‐patch RFID tag antenna scattering analysis
Authors: Lee K. J. , Kim D. , Kim M. , Tanaka M. , Matsugatani K.
Published: August 2006

A dielectric‐filled metal‐patch antenna combinable with an internal RFID IC chip is introduced. This antenna is designed to operate either in an empty space or on top of large metal surface. The proposed tag antenna's dimension is adjusted to produce the maximum amount of scattered power due to tag's internal‐impedance modulation for the normal incidence angle. A 2.44‐GHz dual‐patch antenna is fabricated to demonstrate the amounts of impedance‐modulated scattered power at various reader‐to‐tag angles depending on the tag antenna radiation pattern. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2241–2244, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21931
Determination of microwave dielectric constant by two microstrip line method combined with EM simulation
Authors: Chang Sheng‐Hsiung , Kuan Hon , Wu Hung‐Wei , Yang Ru‐Yuan , Weng Min‐Hang
Published: August 2006

This paper presents a modified procedure to determine the microwave dielectric constant of substrate by two microstrip line method combined with EM simulation. The dielectric constant of substrate is mapped from the measured transmission phase with those of EM simulation, instead of using the closed form equations between the effective dielectric constant and dielectric constant. A tested example of dielectric constant of FR4 substrate is experimented and extracted to verify the proposed procedure. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2199–2201, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21936
Electrically switchable exhibition of circular Bragg phenomenon by an isotropic slab
Authors: Lakhtakia Akhlesh
Published: August 2006

A slab of an isotropic material with structural chirality in the thickness direction and with either 43m or 23 point group symmetry exhibits the circular Bragg phenomenon in the optical regime, only on the application of a low‐frequency electric field across its two faces. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2148–2153, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21941
A novel single‐fed circularly polarized patch antenna with an opening through the whole structure
Authors: Bernard L.
Published: August 2006

A novel single‐fed circularly polarized antenna is proposed with an hole through the whole antenna structure. Parameter studies are performed and design rules are brought out. Experimental results are compared to simulated ones, illustrating the feasibility and the performances of such antennas. © 2006 Wiley Periodicals,Inc. Microwave Opt Technol Lett 48:2337–2340, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21946
Corrigendum: Ideal and real PBG multilayers of negative and positive phase velocity materials in a parallel‐plate waveguide
Authors: Depine Ricardo A. , Martínez Ricci María L. , Lakhtakia Akhlesh
Published: August 2006

Originally published in Microwave Opt Technol Lett 48: (2006); 1945–1953. Comparison of guided wave propagation (a) in a parallel‐plate waveguide with perfectly conducting walls and filled with either real or ideal photonic bad gap (PBG) multilayers whose unit cell comprises a positive phase velocity and a negative phase velocity layers, and (b) in the stratification direction as well as obliquely in the same PBG multilayers but of infinite transverse extent assists in the explanation of several band‐gap features and reflectance peaks, particularly those associated with zero average refractive index, computed for (a). © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2365–2372, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22022
Effects of arginine‐glycine‐aspartic acid (RGD) containing snake venom peptides on parthenogenetic development and in vitro fertilization of bovine oocytes
Authors: White K.L. , Passipieri M. , Bunch T.D. , Campbell K.D. , Pate B.
Published: August 2006

The ability of synthetic arginine‐glycine‐aspartic acid (RGD)‐containing peptides to induce intracellular calcium transients similar to those observed at fertilization by spermatozoa in the bovine has been reported (Campbell et al., 2000: Biol Reprod 62:1702–1709; Sessions et al., 2006. Mol Reprod Dev). These results also indicated the ability of synthetic RGD‐containing peptides to induce activation and subsequent parthenogenetic development to the blastocyst stage, although, at numbers lower than observed with control in vitro fertilization (IVF). Evidence has been provided indicating the important effect of surrounding regions on the biological activity of the RGD sequence (Zhu and Evans, 2002; Sessions et al., 2006). The current experiments were designed to use natural RGD‐containing sequences (disintegrins) to understand their effects. A total of three RGD‐containing snake venom peptides (Kistrin (K), Elegantin (Ele), and Echistatin (Ech)) and one nonRGD‐containing venom (Erabutoxin B (EB; control) were used at three concentrations (0.1, 1, and 10 µg /ml) to induce parthenogenetic development to the blastocyst stage and in conjunction (1.0, 5.0, and 10 µg/ml) with spermatozoa to evaluate competitive inhibition of fertilization and subsequent development. A (P < 0.01) higher number of bovine oocytes developed to the blastocyst stage after incubation with K, Ele and Ech at 1.0 µg/ml, and was not different (P > 0.01) from IVF control. Fertilization was significantly reduced (P < 0.01) at all concentrations of K, Ele and Ech as compared to IVF control. No reduction (P > 0.05) was observed in EB (nonRGD) treated oocytes. These results support the involvement of a disintegrin–integrin interaction at fertilization in the bovine resulting in activation and subsequent development. Mol. Reprod. Dev. 74: 88–96, 2007. © 2006 Wiley‐Liss, Inc.
Requirements of Src family kinase during meiotic maturation in mouse oocyte
Authors: Zheng Ke‐Gang , Meng Xiao‐Qian , Yang Yong , Yu Yuan‐Song , Liu Dai‐Cheng , Li Yun‐Long
Published: August 2006

The Src family kinase (SFK) is important in normal cell cycle control. However, its role in meiotic maturation in mammalian has not been examined. We used confocal microscope immunofluorescence to examine the in vitro dynamics of the subcellular distribution of SFK during the mouse oocyte meiotic maturation and further evaluated the functions of SFK via biochemical analysis using a specific SFK pharmacological inhibitor, PP2. Our results showed that nonphospho‐SFK was absent in oocyte upon its release from follicle. Nonphospho‐SFK appeared in cytoplasm 0.5 hr after the release of oocyte and translocated to germinal vesicle (GV) before germinal vesicle breakdown (GVBD). After GVBD, nonphospho‐SFK colocated with condensed chromosomes. In occyte at metaphase I (MI) and telophase I, nonphospho‐SFK accumulated in the cortex and the cleavage furrow respectively besides its existence in cytoplasm in both stages. In oocyte at metaphase II (MII), nonphospho‐SFK concentrated at the aligned chromosomes. In contrast, phospho‐SFK was absent in oocyte until 1 hr after its release from the follicle. Phospho‐SFK accumulated in the GV, the cortex, and cytoplasm immediately prior to GVBD. After GVBD, phospho‐SFK evenly distributed in oocyte. In oocyte at MII, phospho‐SFK localized throughout the cytoplasm and under the egg member. When the SFK activity was inhibited, the oocyte failed to initiate GVBD, could not go into MII, and could not extrude the first polar body. Our results demonstrated that SFK is required for meiotic maturation in mouse oocyte. Mol. Reprod. Dev. 74: 125–130, 2007. © 2006 Wiley‐Liss, Inc.
Reversible and irreversible effects of chemical fixation on the NMR properties of single cells
Authors: Purea Armin , Webb Andrew G.
Published: August 2006

The effects of chemical fixation are known to alter MR parameters, such as relaxation times and the apparent diffusion coefficient (ADC) of water. It is often assumed that such changes are reversible after samples have been reimmersed in a buffer solution for a sufficient period of time. In this study we characterize the changes associated with fixation of single Xenopus laevis oocytes and their subsequent reimmersion in buffer. Substantial reductions in both T1 and T2 values were measured for all compartments of the cell after fixation, with the cytoplasm showing larger changes than the nucleus. After reimmersion in buffer, there were small but statistically significant differences in MR parameters between fresh and reimmersed cells. Experiments with a gadolinium (Gd) contrast agent showed evidence of irreversible changes in the permeability of cellular membranes to small molecules. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Absolute quantification of myocardial perfusion under adenosine stress
Authors: Ritter Christian , Brackertz Anita , Sandstede Jörn , Beer Meinrad , Hahn Dietbert , Köstler Herbert
Published: August 2006

The prebolus technique allows one to quantify perfusion in the human heart with a low variability by means of MRI. In this study the prebolus technique was used to determine quantitative perfusion values in the human heart under adenosine stress and to measure the myocardial perfusion reserve (MPR). Twelve healthy volunteers were examined using the multislice prebolus technique with 1/4 cc Gd‐BOPTA. Signal intensity (SI) time courses were evaluated in 288 manually segmented sectors at rest and stress. Myocardial perfusion was determined by deconvolution of the SI time courses with the arterial input function (AIF) from the prebolus scan. The mean stress perfusion value was 1.78 ± 0.53cc/g/min, and the mean rest perfusion was 0.52 ± 0.11cc/g/min, resulting in a mean MPR of 3.59 ± 1.26. The measured values correlate well with data from animal models and human positron emission tomography (PET) studies. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Adductor T and H reflexes in humans
Authors: Ertekin Cumhur , Bademkiran Fikret , Tataroglu Cengiz , Aydogdu Ibrahim , Karapinars Nevin
Published: August 2006

In the belief that changes in the adductor reflex (AR) may be helpful in evaluating lumbar root and plexus lesions, expression of the AR was studied in 43 healthy human subjects. ARs elicited with an electronic reflex hammer were recorded from the inner side of the proximal thigh using needle and surface electrodes, and patellar reflexes (PRs) were recorded simultaneously. These reflexes were obtained by tapping the ipsilateral medial aspect of the knee, the contralateral patellar tendon, the ipsilateral and contralateral anterior superior iliac spines, and the Achilles tendon. The H reflex of the obturator nerve was also evaluated in 17 cases. ARs were evoked consistently by tapping the ipsilateral medial aspect of the knee and by contralateral patellar tap, and by tapping ipsilateral and contralateral anterior superior iliac spines when a needle recording electrode was used. Sometimes an Achilles tendon tap also elicited the AR ipsilaterally. By contrast, the PR could only be elicited by a tap to the ipsilateral patellar tendon. ARs have somewhat different features than other well‐known tendon reflexes such as the PR and are recorded consistently when a needle electrode is used, being elicited from both distal and proximal areas of the legs by tapping the Achilles tendon or anterior superior iliac spines unilaterally or bilaterally. Their role in evaluating lumbar root disease and monitoring adductor spasticity merits investigation. Muscle Nerve, 2006
Efficient generation of cycle time‐throughput curves through simulation and metamodeling
Authors: Yang Feng , Ankenman Bruce , Nelson Barry L.
Published: August 2006

A cycle time‐throughput (CT‐TH) curve, which quantifies the relationship of long‐run average cycle time to throughput rate, plays an important role in strategic planning for manufacturing systems. In this paper, a nonlinear regression metamodel supported by queueing theory is developed to represent the underlying CT‐TH curve implied by a manufacturing simulation model. To estimate the model efficiently, simulation experiments are built up sequentially using a multistage procedure. Extensive numerical experiments are presented to demonstrate the effectiveness of the proposed procedure. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007
Paternal occupational exposure to electro‐magnetic fields as a risk factor for cancer in children and young adults: A case‐control study from the North of England
Authors: Pearce Mark S. , Hammal Donna M. , Dorak M. Tevfik , McNally Richard J.Q. , Parker Louise
Published: August 2006

Background

Numerous studies have implied that paternal occupational exposures, in particular electromagnetic fields (EMF) and ionizing radiation, may be involved in the etiology of childhood cancers. We investigated whether an association exists between paternal occupations at birth involving such exposures and cancer risk in offspring, using data from the Northern Region Young Persons' Malignant Disease Registry (NRYPMDR).

Procedure

Cases (n = 4,723) were matched, on sex and year of birth, to controls from two independent sources: (i) all other patients from the NRYPMDR with a different cancer, (ii) 100 cancer‐free individuals per case from the Cumbrian Births Database. An occupational exposure matrix was used to assign individuals to exposure groups.

Results

There was an increased risk of leukemia among the offspring of men employed in occupations likely to be associated with EMF or radiation exposures (OR 1.31, 95% CI 1.02–1.69), particularly in males aged less than 6 years (OR 1.81, 95% 1.19–2.75). No significant association was seen in females. Increased risks were also seen for chondrosarcoma (OR 8.7, 95% CI 1.55–49.4) and renal carcinoma (OR 6.75, 95% CI 1.73–26.0). These associations were consistent between control groups and remained after adjustment for socio‐economic status.

Conclusions

This large case‐control study identified a significantly increased risk of leukemia among the offspring of men likely to have been occupationally exposed to EMF, with differing associations between males and females. Increased risks of chondrosarcoma and renal carcinoma were also seen, although based on smaller numbers. Further detailed investigations in this area are required to understand this association. Pediatr Blood Cancer 2007;49:280–286. © 2006 Wiley‐Liss, Inc.
Distinct fluctuations of ammonia levels during asparaginase therapy for childhood acute leukemia
Authors: Steiner M. , Attarbaschi A. , Kastner U. , Dworzak M. , Haas O.A. , Gadner H. , Mann G.
Published: August 2006

Background

The enzyme asparaginase (L‐Asp) catalyses the hydrolysis of the non‐essential amino acids asparagine and glutamine to aspartic and glutamic acid and ammonia. Ammonia therefore represents a direct metabolite of the biochemical reaction induced by this enzyme. However, data regarding the dynamics and clinical relevance of ammonia levels during L‐Asp therapy are lacking.

Procedure

We prospectively followed the dynamics of ammonia levels during L‐Asp containing induction therapy according to the ALL‐BFM 2000 protocol in 10 pediatric patients with acute lymphoblastic leukemia (ALL), in order to assess the possible relevance of ammonia levels for clinical practice and its use as a possible surrogate parameter of L‐Asp enzyme activity.

Results

We observed a significant elevation of ammonia levels 1 day after intravenous L‐Asp administration with ammonia levels reaching up to the seventh fold of normal values, followed by a steep decline to basal values within another 2 days, resulting in an undulating course of ammonia concentrations during L‐Asp containing induction treatment.

Conclusions

Although there are potential neurotoxic properties of ammonia, central nervous system (CNS) toxicity has not been observed in our study and is generally not seen as a common side effect of L‐Asp therapy. Furthermore, due to the characteristic fluctuation profile, ammonia levels may represent a suitable surrogate parameter of L‐Asp enzyme activity and may enable the monitoring of silent inactivation of L‐Asp. Pediatr Blood Cancer 2007;49:640–642. © 2006 Wiley‐Liss, Inc.
Extreme thrombocytosis associated with transient myeloproliferative disorder with Down Syndrome with t(11;17)(q13;q21)
Authors: Park Eun‐Sil , Kim So‐Young , Yeom Jung‐Suk , Lim Jae‐Young , Park Chan‐Hoo , Youn Hee‐Shang
Published: August 2006

A female patient with Down Syndrome (DS) had neonatal thrombocytosis with platelet counts exceeding 2,000 × 103/µL and transient myeloproliferative disorder (TMD). Platelet counts remained elevated the first 2 months of life. A translocation located between chromosomes 17 and 11 was observed. We describe a patient with thrombocytosis and TMD showing an 11q13 translocation. The leukocytosis and thrombocytosis improved after an exchange transfusion. Pediatr Blood Cancer 2008;50:643–644. © 2006 Wiley‐Liss, Inc.
Optimizing the diffused regions of interdigitated backside buried contact solar cells
Authors: Guo Jiun‐Hua , Cotter Jeffrey E.
Published: August 2006

Recombination and a number of other important factors must be considered in the optimization of the diffused regions of high‐efficiency silicon solar cells. In this paper, we examine issues related to the four types of diffusions used in rear‐junction, interdigitated backside buried contact solar cells made on n‐type silicon wafers: the phosphorus‐diffused front‐surface field (FSF), the boron‐diffused emitter, and the boron and the phosphorus diffused contact regions. Dark saturation current density, effective lifetime, implied open‐circuit voltage and sheet resistance are characterized for the optimization of the above‐mentioned diffused regions. Diffusion uniformity and the avoidance of the diffusion‐induced dislocations are also discussed for the heavily diffused, metal coated contact diffusions. It is found that the optimal sheet resistances of the FSF for planar and textured surfaces are 120 Ω/□ and 105 Ω/□ respectively, whereas the optimal post‐processing sheet resistance for the boron emitter is approximately 100 Ω/□. Moreover, sheet resistance as heavy as 10–20 Ω/□ for the boron groove diffusion and 5–10 Ω/□ for the phosphorus groove diffusion have been achieved without introducing the diffusion‐induced misfit dislocations. Careful consideration of the issues discussed here led to an absolute efficiency improvement on the planar n‐type IBBC solar cell of more than 0·6%. Copyright © 2006 John Wiley & Sons, Ltd.
Application of serum protein fingerprint in diagnosis of papillary thyroid carcinoma
Authors: Wang Jia‐Xiang , Yu Jie‐kai , Wang Li , Liu Qiu‐Liang , Zhang Jiao , Zheng Shu
Published: August 2006

To find new biomarkers and establish serum protein fingerprint models for early diagnosis and preoperative staging of papillary thyroid carcinoma, we employed SELDI‐TOF‐MS and bioinformatics tools. A total of 116 samples were analyzed in this study. The first 80 samples were analyzed by SELDI‐TOF‐MS and two biomarker patterns were identified. Pattern 1 distinguishes patients with papillary thyroid carcinoma from healthy individuals. Pattern 2 distinguishes papillary thyroid carcinoma from benign thyroid nodes. The remaining 29 samples were analyzed on the second day and served as an independent test set. The analysis of this independent test set yielded a specificity of 80.0% and a sensitivity of 88.9% for pattern 1 and a specificity of 80.0% and a sensitivity of 80.0% for pattern 2. Two additional biomarker patterns were identified to distinguish different stages of the papillary thyroid carcinoma (pattern 3) with an accuracy of 77.1% and different pathological types of thyroid carcinoma (pattern 4) with an accuracy of 88.1%. Taken together, the SELDI‐TOF‐MS technique combined with bioinformatics approaches can not only facilitate the discovery of better biomarkers for papillary thyroid carcinoma but also provide a useful tool for molecular diagnosis in the future.
Improved protocol for chromatofocusing on the ProteomeLab PF2D
Authors: Barré Olivier , Solioz Marc
Published: August 2006

Beckman‐Coulter has recently introduced the ProteomeLab PF2D™ for 2‐D liquid separation of protein samples. The system features separation in the first dimension by chromatofocusing, followed by RP chromatography in the second dimension, allowing the analysis of complex proteomics samples. When used by the standard protocol, reproducibility and column life times are limited, making the use of the instrument very costly. We here present an improved protocol for chromatofocusing, which enhances column life by at least fivefold.
Mitochondrial protein patterns correlating with impaired insulin secretion from INS‐1E cells exposed to elevated glucose concentrations
Authors: Nyblom Hanna K. , Thorn Kristofer , Ahmed Meftun , Bergsten Peter
Published: August 2006

Extended hyperglycaemia leads to impaired glucose‐stimulated insulin secretion (GSIS) and eventually β‐cell apoptosis in individuals with type 2 diabetes mellitus. In an attempt to dissect mechanisms behind the detrimental effects of glucose, we focused on measuring changes in expression patterns of mitochondrial proteins. Impaired GSIS was observed from INS‐1E cells cultured for 5 days at 20 or 27 mM glucose compared to cells cultured at 5.5 or 11 mM glucose. After culture, mitochondria were isolated from the INS‐1E cells by differential centrifugation. Proteins of the mitochondrial fraction were bound to a strong anionic surface (SAX2) protein array and mass spectra generated by SELDI‐TOF‐MS. Analysis of the spectra revealed proteins with expression levels that correlated with the glucose concentration of the culture medium. Indeed, such differentially expressed proteins created patterns of protein changes, which correlated with impairment of GSIS. In conclusion, the study reveals the first glucose‐induced differentially expressed patterns of β‐cell mitochondrial proteins obtained by SELDI‐TOF‐MS.