bluuebunny/crossref_metadata_2025_split huggingface dataset:
A dual‐band GPS microstrip antenna
Authors: Su Chih‐Ming , Wong Kin‐Lu 
Published: August 2002

AbstractDesign considerations and experimental results of a dual‐band circularly polarized stacked microstrip antenna for GPS operations at 1227 and 1575 MHz are presented. The antenna is achieved by stacking two corner‐truncated square microstrip patches. The obtained circular polarization (CP) bandwidths, determined from 3‐dB axial ratio, are about 15 MHz (about 1.2%) and 17 MHz (about 1.1%) at 1227 and 1575 MHz, respectively. Good CP radiation patterns and antenna gain have also been observed. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 238–240, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10285
A novel primary feed antenna for plane sheet metallic reflectors for base stations
Authors: Ali M. , Stuchly S. S. 
Published: August 2002

AbstractA new type of primary feed antenna for plane sheet metallic reflectors is introduced. Reflector dimension can be reduced by 46% compared to a half‐wave dipole feed when the directivity, beamwidth, and front‐to‐back ratio are fixed at 7.6 dBi, 100°, and 15.5 dB. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 407–408, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10336
Improving the coupled‐mode method by means of step functions: Application to partial‐height isotropic or anisotropic dielectric parallel‐plate waveguides
Authors: Gómez Álvaro , Ipiña Juan S. , Solano Miguel A. , Prieto Andrés , Vegas Ángel 
Published: August 2002

AbstractThe main drawback of the coupled‐mode method is the poor convergence and accuracy of the discontinuous field components. The greater the discontinuity, the worse these problems become. This Letter presents an improvement of the method, allowing this drawback to be minimized. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 408–414, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10337
On the propagation of electromagnetic waves through parabolic cylindrical chiroguides with small flare angles
Authors: Choudhury P. K. 
Published: August 2002

AbstractWith the use of Maxwell's field equations, an analytical investigation of the propagation of electromagnetic (EM) waves through a three‐layer parabolic cylindrical chirowaveguide is presented; different regions of the guide have different values of chirality admittance. The analytical approaches to derive the dispersion relations and the eigenvalue equations for cutoff are discussed under the assumption of small flare angles of the parabolic cylindrical boundaries. However, more emphasis is given on the modal field cutoffs. It is observed that the bunching tendency of field cutoffs, which is seen in the cases of parabolic cylindrical dielectric guides, is greatly affected in this case, which is attributed to the presence of chirality in the medium. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 414–419, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10338
On the measurement of the complex permittivity of layers embedded in a multilayered dielectric material with the use of a free‐space method
Authors: Garcia‐Ruiz Israel , Aviles‐Castro Carlos D. , Jardón‐Aguilar Hildeberto , Guerra‐Vargas Juan 
Published: August 2002

AbstractFree‐space method approaches for obtaining the complex permittivity of dielectric layers embedded in a multilayer dielectric material are investigated. Solids, liquids, and granular materials have been tested; a description of the de‐embedding process is presented in detail, as are the measured permittivity values. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 422–426, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10340
Experimental investigation of a 4‐FBG TDM sensor array with a tunable laser source
Authors: Chan C. C. , Jin W. , Demokan M. S. 
Published: August 2002

AbstractThe performance of a time‐division‐multiplexed fiber Bragg grating sensor array that uses a tunable laser source has been investigated. It was found that the wavelength detection accuracy is affected by the extinction ratio of the optical pulse modulator used for input pulse generation. Experiments with a 4‐FBG sensor array demonstrated a strain resolution of 0.7 με with an optical pulse modulator of −24‐dB extinction ratio. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 435–437, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10343
Compact planar inverted‐F patch antenna for triple‐frequency operation
Authors: Hsiao Fu‐Ren , Wong Kin‐Lu 
Published: August 2002

AbstractA novel compact planar inverted‐F patch antenna with two shorted branch strips for triple‐frequency operation at about 900, 1800, and 2450 MHz is presented. The antenna has compact dimensions of 5.5 mm in height and 7.5 × 24 mm2 in area. The two shorted branch strips are printed on an FR4 substrate, and supported above a ground plane by plastic posts. In addition, the longer branch strip, which controls the operations at about 900 and 1800 MHz, is printed on both sides of the FR4 substrate, leading to the reduction in antenna dimensions. On the other hand, the shorter branch strip, printed on one side of the FR4 substrate only, controls the operation at about 2450 MHz. Details of the antenna design and experimental results are presented and discussed. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 459–462, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10350
Assessment of the effectiveness of a boundary value approach for the estimation of the electric field distribution in exposed phantoms
Authors: Caorsi Salvatore , Bermani Emanuela , Massa Andrea 
Published: August 2002

AbstractIn this Letter a new approach for the estimation of the electric field distribution in phantoms exposed to not completely specified or unknown electromagnetic source is proposed. Starting from the knowledge of the tangential component of the electric field on a surface around the object, the problem is recast in a boundary value problem numerically solved by means of a finite‐element procedure. Neither description nor modeling of the source is required. Numerical results concerning a two‐dimensional geometry are provided in order to assess the effectiveness of the proposed approach showing its capabilities and current limitations. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 41–43, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10367
Extraction of equivalent‐circuit parameters of interconnection lines with the use of the finite‐difference time‐domain method
Authors: Farahat Nader , Mittra Raj 
Published: August 2002

AbstractThis Letter presents a simple technique for extracting the equivalent parameters of transmission‐line interconnects based on the finite‐difference–time‐domain (FDTD) method. The transmission line containing the discontinuity is divided into a set of uniform segments of short‐length line. Next, the parameters of each of these segments are extracted by substituting the FDTD solution into the telegrapher's equations. The accuracy of the method is comparing by the results with those derived via the method of moments (MoM). The equivalent circuit can be used in a SPICE simulator to predict the performance of interconnect with a view to enhancing the characterization and design of high‐speed digital circuits. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 59–61, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10373
Reflectivity spectra evolution in grating structures with fractionally organized gaps
Authors: Hattori Haroldo T. , Schneider Vitor M. , Barbosa Carmen L. , Cazo Rogério M. 
Published: August 2002

AbstractGratings with quarter‐wavelength gaps separating subgratings have been analyzed extensively in the literature, where they have found applications for distributed feedback lasers, filters, etc. In these structures, the gaps always had quarter‐wavelength lengths. We modify these structures by starting with a quarter‐wavelength gap, but ordering the subsequent gaps following a scaling factor of 0.8. The subgratings are assumed to be uniform and to have equal lengths. The reflectivity spectra of these gratings are analyzed by using the transfer matrix method, with emphasis on the wavelength range near the central lobe. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 42–45, 2001.
Scanning properties of sequentially rotated linear arrays of circularly polarized patch radiators
Authors: García‐García Quiterio 
Published: August 2002

AbstractThis paper presents a theoretical analysis of the effect of beam scanning and amplitude tapering on the cross‐pol level of sequentially rotated linear arrays composed of circularly polarized patch antenna elements. Arrays of eight elements are considered to illustrate the analysis. Several sequential phase distributions are analyzed in terms of the cross‐pol level cancellation effect over the antenna field of view. These arrangements are analyzed in terms of the location of the maximum cross‐pol peak levels and their values. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 343–350, 2001.
Investigation of the performance of the resistive voltage source used for the FDTD analysis of microstrip circuits
Authors: Zhao An Ping , Alinikula Petteri 
Published: August 2002

AbstractIn this paper, the performance of the resistive voltage source (RVS) model used for the FDTD analysis of microstrip circuits is evaluated. It is found that, when the actual physical impedance of a microstrip line is used for assigning a constant value of Rs into the corresponding electric nodes in the RVS region, the model often induces quite large reflections. Detailed numerical investigations indicate that the performance of the RVS model can be greatly enhanced when the effective impedance (which is determined by examining the maximum value of the calculated voltage between the strip line and the ground plane), instead of the physical impedance, of the microstrip line is used for the RVS model. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 378–381, 2001.
Irradiators for the study of microwave sterilization effects
Authors: Posadas V. Vicente González , Marco R. , Rodríguez Martín José María , Frias Carlos Rueda , Jiménez Martín José Luis , Martín Pascual Carlos 
Published: August 2002

AbstractWe show, in this paper, the results obtained in the sterilization process by using different irradiating structures. Starting from our earlier findings of the existence of an important synergy on the killing effect caused by the simultaneous application of oxidant agents such as hydrogen peroxide and microwave irradiation, we have now extended the work to identify the power threshold and the optimum frequency range for the effect. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 404–406, 2001.
Simulation of a high‐speed radio link under OPNET
Authors: Carsenat D. , Mathieu S. , Besse O. , Guedira R. , Vaudon P. , Monediere T. , Jecko B. 
Published: August 2002

AbstractA high‐speed radio link, such as the LMDS (local multipoint distribution system), proves to be quite complex to simulate under OPNET modeler radio from the electromagnetic propagation point of view. This paper describes the introduction of a 3‐D radiation diagram in the simulation and integration of software computing the electromagnetic propagation, taking note of the multipath. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 24–27, 2001.
Radiation parameter extraction for transmission‐line interconnects by using method‐of‐moments solutions
Authors: Liu Y. W. , Hong J. S. , Liu W. M. , Mei K. K. 
Published: August 2002

AbstractIn this paper, an extraction technique of radiation sources for nonuniform transmission lines is proposed for the first time. The technique, based on solutions of the method of moments (MoM), can numerically determine the coefficients of nonuniform transmission‐line equations, in which radiation parameters are included. Numerical examples show that the radiation effect of a right‐angle microstrip‐line bend is indeed stronger than that of a corresponding 45° mitered bend at high frequency. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 37–39, 2001.
Compact L‐strip capacitively coupled patch antenna with a folded radiating patch for a DCS base station
Authors: Chang Fa‐Shian , Wong Kin‐Lu 
Published: August 2002

AbstractWith the use of a folded radiating patch and an L‐strip capacitively coupled feed, a novel compact patch antenna suitable for a DCS (1710–1880 MHz) cellular system base‐station application is presented. Owing to the folded radiating patch used, the patch length in the excitation direction can be greatly reduced by more than 30% compared to the case with a conventional radiating patch. Many prototypes have been constructed, and the experimental results are presented. The effects of the folded radiating patch on the antenna's radiation characteristics are also discussed. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 60–62, 2001.
Pharmacokinetics of doxorubicin in children with acute lymphoblastic leukemia: Multi‐institutional collaborative study
Authors: Frost B.‐M. , Eksborg S. , Björk O. , Abrahamsson J. , Behrendtz M. , Castor A. , Forestier E. , Lönnerholm G. 
Published: August 2002

AbstractBackgroundIn adults, it has been shown that the pharmacokinetics of doxorubicin are highly variable, despite standardization of the dose based on body surface area (BSA). The purpose of this study was to determine the plasma concentrations of doxorubicin and its active metabolite doxorubicinol in children treated for acute lymphoblastic leukemia (ALL).ProcedureChildren, 107 in number, aged 1.3–17.3 years, were studied at Day 1 of induction therapy according to the current Nordic protocol. Five infants, 3–9 months old, were also included. Plasma samples were drawn 23 hr after the start of a 24‐hr infusion of doxorubicin 40 mg/m2, and analyzed by reversed‐phase liquid chromatography.ResultsThere was a more than 10‐fold difference between patients in dose normalized plasma concentration of doxorubicin, median 62.8 ng/ml, range 22.6–334 ng/ml. The doxorubicin concentrations differed significantly between age groups (P = 0.003). Children aged 4–6 years had the highest doxorubicin concentrations, median 77.9 ng/ml, followed by 2–4‐year‐old children, median 64.3 ng/ml. Both younger and older children had median values of about 50 ng/ml. Patients with white blood cell (WBC) count > 50 × 109/L at diagnosis had significantly lower doxorubicin concentrations, median 55.3 ng/ml, than those with WBC count < 10 × 109/L, median 64.4 ng/ml (P = 0.015). There was no difference in doxorubicin concentration between boys and girls. No correlation was found between doxorubicin levels and serum aminotransferases or serum creatinine. The concentration of doxorubicinol was 13% (median value) of that of doxorubicin. Four infants, 7–9 months old, had plasma clearance between 350–431 ml/min/m2, which is in the same range as in older children. A 3‐month‐old infant had a clearance of 181 ml/min/m2.ConclusionsThe age groups who had the highest doxorubicin concentrations, (2‐) 4–6‐year‐old children, are known to make up a large proportion of standard risk ALL cases with good prognosis. The correlation between doxorubicin plasma levels and clinical effect needs further study. The influence of age, body composition, and tumor burden on the pharmacokinetics of antineoplastic drugs should also be further explored, aiming at improvements in the current dosing regimen based on BSA. Med. Pediatr. Oncol. 2002;38:329–337. © 2002 Wiley‐Liss, Inc.
In vitro drug resistance profile of Philadelphia positive acute lymphoblastic leukemia is heterogeneous and related to age: A report of the Dutch and German Leukemia Study Groups
Authors: Woerden N.L. Ramakers‐van , Pieters R. , Hoelzer D. , Slater R.M. , den Boer M.L. , Loonen A.H. , Harbott J. , Janka‐Schaub G.E. , Ludwig W‐D , Ossenkoppele G.J. , van Wering E.R. , Veerman A.J.P. 
Published: August 2002

AbstractBackgroundThe t(9;22)(q34;q11) translocation leading to the Philadelphia (Ph) chromosome resulting in BCR‐ABL gene fusion is associated with a poor prognosis in acute lymphoblastic leukemia (ALL).ProcedureWe studied the relation between t(9;22), determined by karyotype, fluorescence in situ hybridization (FISH) or polymerase chain reaction (PCR), and in vitro drug resistance, measured by the MTT assay, in precursor B‐cell ALL at diagnosis. The findings in twenty‐one Ph‐0positive (Ph+) childhood common/precursorB (c/preB) cases were compared with 254 Ph‐negative (Ph−) ALL cases.ResultsA large range of LC50 values was found within the Ph+ patients. Moreover, LC50 values did not differ significantly between Ph+ and Ph− samples for prednisolone, dexamethasone, L‐asparaginase, vincristine, anthracyclines, thiopurines, epipodophyllotoxins, and 4H00‐ifosfamide, even after matching for important prognostic features (age, white blood cell count (WBC), and immunophenotype). Adult Ph+ (n = 12) ALL was more resistant to prednisolone (> 270‐fold, P = 0.030), and displayed an overall tendency to resistance when compared to matched cases of Ph− (n = 15) adult precursor B‐cell ALL. Within Ph+ ALL, in vitro prednisolone resistance increased significantly with age (P = 0.006). The expression of lung resistance protein (LRP), but not P‐glycoprotein (P‐gp) or multidrug resistance protein (MRP), was significantly higher in all Ph+ patients.ConclusionsBoth childhood and adult Ph+ precursor B‐cell ALL samples display a heterogeneous in vitro resistance profile, with relatively sensitive and resistant cases. The adult Ph+ samples, however, are generally more resistant compared to matched Ph− controls, reaching significance for prednisolone. The correlation of prednisolone resistance with age within the Ph+ cases might help explain the poorer prognosis of adult Ph+ ALL. Med Pediatr Oncol 2002;38:379–386. © 2002 Wiley‐Liss, Inc.
Gene rearrangements in radiation‐induced thyroid carcinogenesis*
Authors: Rabes Hartmut M. 
Published: August 2002

AbstractBackgroundRadiation is an accepted risk factor for thyroid carcinogenesis in children. Recent observations in large cohorts of children and young adults who developed papillary thyroid carcinomas (PTC) related to accidental radiation exposure after the Chernobyl reactor accident revealed typical genetic aberrations shedding light on genetic determinants and mechanisms of radiation‐induced carcinogenesis.ProcedureA molecular genetic analysis was performed on 191 post‐Chernobyl PTC by RT‐PCR, multiplex PCR, DNA sequencing, and in some cases 5'RACE. Determination of point mutations was by means of PCR and either allele‐specific oligonucleotide hybridiziation or SSCP and DNA sequencing.ResultsIn various sporadic thyroid tumor types of adults structural genetic aberrations have been found involving mutations of RAS (codon 12, 13, 61), p53 (exons 5 to 8), Gsα (codon 201 and 227), and, at a low prevalence, the receptor tyrosine kinases RET or NTRK1. In contrast, in radiation‐induced PTC of children RET rearrangements are by far the most prevalent genetic aberrations. In these RET rearrangements, the transmembrane and extracellular domains of RET are lost, and are replaced by parts of other genes at the 5′ end. These genes always contain coiled‐coil domains with dimerization potential and lead to constitutive, ligand‐independent activation of the ret tyrosine kinase domain at the 3′ end of the fusion product. The most frequent radiation‐induced RET gene fusions involve the ELE1 (ARA70) gene, a transcription coactivator of the androgen receptor (PTC3), and H4, a gene of unknown function (PTC1). Both rearrangements originate from DNA double strand breaks with repair by intrachromosomal balanced paracentric inversion and recombination by illegitimate DNA endjoining at small stretches of homologous nucleotide sequences and direct or inverted repeats, without significant breakpoint clusters in the involved introns. In addition, five different RET‐fused genes, RIα, GOLGA5, HTIF, RFG7 and RFG8, have been detected leading to the PTC2, 5, 6, 7 and 8 types of RET rearrangements, respectively. Each fusion leads, in principle, to the same effect: The ret tyrosine kinase is uncoupled from its stringent physiological regulation by replacement of its 5′ end and is aberrantly activated by the 5′ parts of fused genes in thyrocytes that do not normally express ret tyrosine kinase. Ectopic ret expression, clonal expansion and early invasion are peculiar to the affected cells. The RET‐fused gene is obviously decisive for modulating tumor development: ELE1/RET rearrangements lead to most rapid tumor progression and are related to the solid variant of PTC, in contrast to H4/RET rearrangements connected with papillary or follicular variants of PTC.ConclusionsTypical genetic aberrations are produced by radioiodine uptake in the juvenile thyroid gland. They act as determinants of phenotype, biology, and clinical course of radiation‐induced papillary thyroid carcinomas. Med. Pediatr. Oncol. 36:574–582, 2001. © 2001 Wiley‐Liss, Inc.
Thyroidal uptake and radiation dose after repetitive I‐131‐MIBG treatments: Influence of potassium iodide for thyroid blocking
Authors: Brans Boudewija , Monsieurs Myriam , Laureys Genevieve , Kaufman Jean‐Marie , Thierens Hubert , Dierckx Rudi A. 
Published: August 2002

AbstractBackgroundIn I‐131‐MIBG therapy, I‐131‐iodide can be released from the I‐131‐MIBG molecule. Hypothyroidism might result from the undesirable irradiation of the thyroid gland. To prevent this, stable iodide such as potassium iodide (KI) is given to oversaturate the thyroid before I‐131‐MIBG is administered.ProcedureIn the present study, the incidence of hypothyroidism (elevated TSH) was correlated with the thyroidal uptake of I‐131 and dose (MIRD dosimetry) after 35 individual treatments in ten patients. Iodine‐131‐MIBG therapy was performed using a modified dosage of 1.9–11.1 GBq (50–300 mCi) IV. Premedication with KI was done as recommended with a dose of 100 mg KI orally from 2 days before until 4 weeks after I‐131‐MIBG.ResultsThe absorbed thyroidal dose amounted to a very variable range of 0.2 (patient # 1) up to 30.0 (patient 3) Gy with 7.1 ± 7.9 Gy per treatment and 24.1 ± 19.2 Gy per patient (mean ± SD), despite the same and compliantly taken KI premedication protocol. Up to now, 4/10 or 40% of patients have developed hypothyroidism after a mean follow‐up period of 11 months and a mean total administered dose of 18.7 GBq (505 mCi). A trend towards higher thyroidal doses was seen in the hypothyroid patients.ConclusionsThis study observes a general high inter‐ and intra‐individual variability in radio‐iodide uptake in the thyroid after I‐131‐MIBG therapy despite KI premedication, as well as possible occurrence of hypothyroidism. A dose‐response relationship needs confirmation on a larger cohort of patients to reach statistical value. An alternative thyroid cytoprotection strategy for possible long‐term survivors may be considered. Med Pediatr Oncol 2002;38:41–46. © 2002 Wiley‐Liss, Inc.