bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of three new culture media for the cultivation and isolation of Leishmania parasites
Authors: Limoncu Me. , Özbilgin A. , Balcioḡlu İc. , Özbel Y. 
Published: May 2004

AbstractThe aim of this study was to establish novel culture media for Leishmania parasites with a potential of obtaining hight amounts of promastigotes with long‐term viability, and consisting of ingredients that were available in microbiology or parasitology laboratories. Other features of these media included no requirement for blood, FCS (Fetal calf serum) or erythrocyte lysate, inexpensiveness and easiness in preparation. In addition, aspiration samples obtained from cutaneous leishmaniasis (CL) suspected patients were cultivated in these media.Three culture media were prepared; trypticase beef extract hemoglobine (TBH) medium, including trypticase, beef extract and yeast extract as the protein source, glucose as the carbohydrate source, FeNH4 and bovine hemoglobine; Peptone‐Yeast extract medium (PY), found to be effective in our previous studies for cultuvation of on Leishmania parasites, with bovine hemoglobine (PYH) and Brain Heart medium, containing bovine hemoglobine (BKH).The number of promastigotes were the highest on day 8 and 13 in RPMI 1640 and BKH medium, respectively. In TBH and PYH, the peak level of reproduction was between day 16 and 19, and it was found to be higher in TBH medium after the day 20. The number of promastigotes were found to be close in BKH, TBH and RPMI‐1640 media and lower in PYH medium.Examination of the cultivation of the aqueous lesion specimens of the 10 CL‐suspected cases in media revealed reproduction in 9 flasks of RPMI‐1640 containing 10% FCS, 7 TBH, 6 BKH and 4 PYH. The differences between the culture media were not found to be statistically significant.These results suggested that, three liquid culture media, assessed in this study, with no requirement for FCS or erythrocyte lysate, were effective in the reproduction of promastigotes, and could be used effectively in the patient isolation and field studies, as well. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Control of pyrimidine biosynthesis in “Pseudomonas alkanolytica” ATCC 21034
Authors: West Thomas P. 
Published: May 2004

AbstractThe control of de novo pyrimidine biosynthesis in the industrially important patent strain “Pseudomonas alkanolytica” ATCC 21034 was investigated. Uracil supplementation of succinate‐grown “P. alkanolytica” cells produced the greatest depression of the de novo pyrimidine biosynthetic pathway enzyme activities. After the pyrimidine limitation of a “P. alkanolytica” orotate phosphoribosyltransferase mutant strain grown on succinate, the pyrimidine biosynthetic pathway enzyme activities were derepressed. The pyrimidine biosynthetic pathway enzyme aspartate transcarbamoylase in “P. alkanolytica” was inhibited by pyrophosphate, cytidine 5′‐triphosphate (CTP), uridine 5′‐triphosphate (UTP), and guanosine 5′‐triphosphate (GTP). (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis of Polypyrrole Microtubes with Actinomorphic Morphology in the Presence of a β‐Cyclodextrin Derivative‐Methyl Orange Inclusion Complex
Authors: Hu Xueqing , Lu Yun , Liu Jinhui 
Published: May 2004

AbstractSummary: Polypyrrole (PPy) microtubes with an actinomorphic morphology are synthesized by a chemical method in the presence of an inclusion complex (IC) of mono [6‐deoxy‐6‐(2‐butenedinitrile‐2,3‐dimercapto sodium salt)]‐β‐cyclodextrin (6‐mnt‐β‐CD) with methyl orange (MO) as a dopant in aqueous solution. The morphologies of the obtained PPy were studied using transmission electron microscopy (TEM). It was found that the IC of 6‐mnt‐β‐CD with MO significantly affects the morphology of the resulting PPy.The morphology of polypyrrole synthesized in the presence of 6‐mnt‐β‐CD/MO, determined by TEM.imageThe morphology of polypyrrole synthesized in the presence of 6‐mnt‐β‐CD/MO, determined by TEM.
Poly[(3,3′‐dimethyl‐1,1′‐biphenyl‐4,4′‐diyl)ethynediyl(2,5‐dioctyl‐1,4‐phenylene)ethynediyl] and a related copolymer – new blue EL polymers
Authors: Joo Sung‐Hoon , Jin Jung‐Il 
Published: May 2004

AbstractElectroluminescence (EL) properties of a new poly(aryleneethynylene) and a related copolymer were studied. They are poly[(3,3′‐dimethyl‐1,1′‐biphenyl‐4,4′‐diyl)ethynediyl(2,5‐dioctyl‐1,4‐phenylene)ethynediyl] (PPEBE) and related copolymer (PPEBE‐co‐mP) containing 20 mole % of 1,3‐phenylene units. Both polymers are blue‐light emitters; the former was found to perform better than the latter when the light‐emitting diode (LED) device had the configuration of ITO/PEDOT/polymer/Li:Al. The device constructed with the former polymer exhibited the external quantum efficiency of 0.05 and the maximum brightness higher than 400 cd/m2 with its EL spectrum showing maxima at λ = 445 and 472 nm. The performance of the device constructed with the copolymer was about one fifth of the device fabricated with the homopolymer.
Frequency analysis of diffusion in 1D systems with energy and spatial disorder
Authors: Pitarch Angeles , Garcia‐Belmonte Germà , Bisquert Juan 
Published: May 2004

AbstractWe have analyzed the frequency‐dependent features of diffusive transport of mobile carriers by hopping in a disordered environment composed of varying energy barriers. We developed a simple approach based on the solution of the master equation for a gradient of concentration (chemical potential) under a sinusoidal perturbation. This method extends the well‐known result of the steady state case, D = {1 / Γ}−1, to the frequency domain. The results of our calculations are in agreement with the approximate analytical solution of the CTRW formalism. We are able to determine the onset of frequency‐dependent diffusivity in terms of probabilities of highest energy barriers.
Quenching of exciplex and charge‐transfer complex fluorescence of poly(N‐vinylcarbazole) – benzanthrone system
Authors: Siegoczyński R.M. , Ejchart W. 
Published: May 2004

AbstractWhen benzanthrone (Bt), a weak electron acceptor, is doped into poly(N‐vinylcarbazole) (PVCz) solution or film, an excited carbazole chromophore (D*) interacts with Bt to form a new exciplex state, which gives a broad fluorescence band (λmax = 440 nm) in solution and a new state, which gives broad fluorescence (λmax = 550 nm) in the film. In order to elucidate the origin of these new states, we have studied the results of experiments for absorption, concentration dependence of the excimer and exciplex fluorescence quenching, both in solution and in the film, and electric field‐induced fluorescence quenching in the film. Taking into account that (i) the new state formation in the PVCz film containing small amounts of Bt enhances the photocurrent in the absorption region, where the photon energy is insufficient to excite polymer molecules directly into the conduction state, (ii) the 550 nm fluorescence of the PVCz ‐ Bt system in film is only partly quenched by electric field, (iii) the appearance of structureless tail in the fluorescence excitation spectrum, the charge transfer interaction model of the PVCz ‐ Bt system in film is proposed.
Improved performance of EBGs on a co‐planar transmission line using tapered distribution
Authors: Padhi Shantanu Kumar 
Published: May 2004

AbstractConventional electromagnetic crystals or electromagnetic bandgaps (EBGs) with uniform distribution show spurious ripples in the pass band and poor stop‐band responses. This paper presents a detailed theoretical investigation of the performance of EBGs on a uniplanar transmission line using tapered distribution. The nonuniform size of the EBGs is used to improve the ripple height, 20‐dB rejection band, and selectivity of the filter over the pass‐band and stop‐band regions. The calculated S parameters exhibit significant improvement in ripple height and rejection bandwidth, as compared with the conventional EBG‐assisted coplanar transmission line. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 128–131, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20228
Resonant influence of small S‐shaped particles on the guided mode of a coplanar line
Authors: Verney E. , Rouiller T. , Simovski C. R. , Sauviac B. , Capraro S. 
Published: May 2004

AbstractArtificial dielectrics prepared as planar grids appear to have potential use and applications at microwaves due to their easy fabrication and their wide range of obtainable properties. Here, we study a grid of metallic S‐particles introduced in the design of a coplanar waveguide and demonstrate the resonant influence of the grid to the S‐matrix of the coplanar waveguide. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 131–133, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20229
1.57‐μm InP‐based resonant‐cavity‐enhanced photodetector with InP/air‐gap Bragg reflectors
Authors: Ren Xiaomin , Huang Hui , Chong Yingzhe , Huang Yongqing 
Published: May 2004

AbstractWe have demonstrated a monolithic and cost‐effective InP‐based resonant‐cavity‐enhanced photodetector with an InP/air‐gap distributed Bragg reflector (DBR) fabricated by using selective wet etching. Peak quantum efficiency is 54% at 1.57 μm, which corresponds to nearly two‐fold enhancement versus a conventional detector of the same absorption depth, a 3‐dB bandwidth of 6.8 GHz was achieved with the active area of 50 × 50 μm2. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 133–135, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20230
Evaluation of the spatial distribution of birefringence in an optical‐fiber link
Authors: Perlicki K. 
Published: May 2004

AbstractWe present a simple method of the calculation of spatial distribution of birefringence in an optical‐fiber link. This method is based on an analysis of the properties of the backscattered optical signal. The analytical results are compared with the numerical results, and excellent agreement is obtained. We demonstrate that the spatial‐birefringence distribution may be obtained from the calculation of the roundtrip Muller matrices derived from only two power‐evolution traces, corresponding to two different angles of the polarizer. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 147–149, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20234
A novel dual‐band F‐inverted antenna printed on a PCMCIA card
Authors: Angelopoulos Evangelos S. , Kostaridis Antonis I. , Kaklamani Dimitra I. 
Published: May 2004

AbstractThis paper presents a novel dual‐band Inverted‐F Antenna (IFA) printed on a PCMCIA card. The antenna is based on the classic λ/4 printed IFA, which incorporates two individual monopoles separated by an L‐shaped slot that is properly optimized to achieve dual‐mode operation at 2.45 and 5.25 GHz. The antenna is aimed to support multiple wireless protocols, such as 802.11b and 802.11a. A prototype has been successfully developed and measured, while simulated and experimental results prove the favorable dual‐band characteristics of the printed antenna. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 153–156, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20236
2D full‐wave finite‐difference frequency‐domain method for lossy metal waveguide
Authors: Wang Bing‐Zhong , Wang Xiaohua , Shao Wei 
Published: May 2004

AbstractThe 2D finite‐difference frequency‐domain method combined with the surface‐impedance boundary condition is applied for the analysis of dispersion characteristics of lossy metal waveguides. Six electromagnetic field components are involved in the final eigen equation. By solving the eigen equation, the method finds the propagation constants for a given frequency. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 158–161, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20238
Low‐phase‐noise CMOS VCO with harmonically tuned LC tank
Authors: Chung Yujin , Lee Jong‐Ryul , Kim Bumman 
Published: May 2004

AbstractA low‐phase‐noise voltage‐controlled oscillator (VCO) has been demonstrated using a harmonically tuned LC resonance tank. In this circuit configuration, the voltage shape at the differential cell is almost rectangular; thus, the cell is switched effectively and the phase noise is reduced. More importantly, the proposed tank suppresses down‐conversion of the noise around 2f0 to the phase noise, due to the 2nd harmonic short of the tank. Therefore, the phase noise of the VCO based on the tank is improved considerably. The VCO for 1‐GHz operation has been realized using a 0.35‐μm CMOS process. It shows a phase noise of −111.6 dBc/Hz at 100 KHz offset, which is a 5.7‐dB improvement over a comparable standard VCO. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 164–167, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20240
L‐strip excited wideband rectangular microstrip antenna
Authors: Lethakumary B. , Menon Sreedevi K. , Aanandan C. K. , Vasudevan K. , Mohanan P. 
Published: May 2004

AbstractThis paper presents the outcome of the experimental studies performed on L‐strip‐fed compact rectangular microstrip antenna. The effect of the feed parameters upon the characteristics of the antenna is studied in detail. The antenna offers an impedance bandwidth of nearly 20% and is suitable for broadband applications. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 173–175, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20243
Comparison study of pattern‐synthesis techniques using neural networks
Authors: Shavit R. , Taig I. 
Published: May 2004

AbstractIn this paper, a comparison study among three neural‐network algorithms for the synthesis of array patterns is presented. The neural networks are used to estimate the array elements' excitations for an arbitrary pattern. The architecture of the neural networks is discussed and simulation results are presented. Two new neural networks, based on radial basis functions (RBFs) and wavelet neural networks (WNNs), are introduced. The proposed networks offer a more efficient synthesis procedure, as compared to other available techniques. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 175–179, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20244
Prenatal screening for Down syndrome: the problem of recurrent false‐positives
Authors: Wald Nicholas J. , Huttly Wayne J. , Rudnicka Alicja R. 
Published: May 2004

AbstractObjectivesIt has been reported that, in prenatal screening programmes for Down syndrome, women who have false‐positive results in one pregnancy have an increased risk of a false‐positive result in a subsequent pregnancy. We examined the effect of this in the screening programme conducted from the Wolfson Institute of Preventive Medicine with a view to determining the magnitude of the effect, and to describe a method of avoiding the problem.MethodsSix thousand four hundred and forty‐eight women were identified who had had two singleton pregnancies without Down syndrome in the screening programme based at the Wolfson Institute of Preventive Medicine, in which both pregnancies were screened using a Quadruple test (maternal age with alphafetoprotein (AFP), unconjugated oestriol (uE3), total or free β‐human chorionic gonadotrophin (hCG) and either free α‐hCG or inhibin‐A as the fourth serum marker).ResultsAmong women who had a false‐positive result in their initial pregnancy, the false‐positive rate in the subsequent pregnancy was high: 20% (46/229), about three times higher than both the overall observed false‐positive rate (6.6%), and the expected false‐positive rate, in subsequent pregnancies that were false–positive in their initial pregnancy (7.5%) (p < 0.001). This arises because serum marker levels in one pregnancy are associated with the levels in a subsequent pregnancy. Using the slope (the regression coefficient b) of each marker level in a subsequent pregnancy regressed on the value in the first pregnancy, it is possible to adjust all marker values in a subsequent pregnancy to allow for the higher‐than‐expected false‐positive rate. This can be done by dividing the observed MoM value for each marker by the ‘expected’ MoM, which is the MoM value in a previous pregnancy raised to the power b.ConclusionsIf a woman has had a false‐positive result in one pregnancy, she is much more likely to have a false‐positive screening result in a subsequent pregnancy than women in general. The problem can be avoided by adjusting the serum markers in all women who have been screened in a previous pregnancy and who have not had a previous pregnancy with Down syndrome. Copyright © 2004 John Wiley & Sons, Ltd.
Characterization of thin polymer‐like films formed by plasma polymerization of methylmethacrylate: A neutron reflectivity study
Authors: Jeon H.S. , Wyatt J. , Harper‐Nixon D. , Weinkauf D.H. 
Published: May 2004

AbstractThe microstructure of the plasma‐polymerized methylmethacrylate (ppMMA) films is characterized using neutron reflectivity (NR) as a function of the plasma reaction time or film thickness. Variation in the crosslink density normal to the substrate surface is examined by swelling the film with a solvent, d‐nitrobenzene (dNB). In the presence of dNB, uniform swelling is observed throughout the bulk as well as at the air surface, and silicon oxide interfaces. The results indicate that the MMA film prepared by plasma polymerization (ppMMA) has a uniform crosslink density from air surface to substrate surface. Additionally, the scattering length density of the plasma‐polymerized MMA film (SLD ≈ 0.750 × 10−6 Å−2) is much lower than that of a conventional PMMA film (SLD = 1.177 × 10−6 Å−2). The increase in film thickness following dNB sorption is 7.5% and at least 36% for the ppMMA and PMMA films, respectively. This suggests that the films formed by plasma polymerization are different from conventional polymers in chemical structure. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2522–2530, 2004
Recognition of lung nodule shadows from chest X‐ray CT images using 3D Markov random field models
Authors: Takizawa Hotaka , Yamamoto Shinji , Nakagawa Tohru , Matsumoto Tohru , Tateno Yukio , Iinuma Takeshi , Matsumoto Mitsuomi 
Published: May 2004

AbstractThis paper presents a scheme for recognizing nodule shadows that are candidate lung cancer lesions from chest X‐ray CT images. In recognizing shadow candidates, their surrounding shadows give useful information. The proposed scheme recognizes nodule shadows by formulating the relationships between shadow candidates and their surrounding shadows in the framework of a three‐dimensional Markov random field model. First, it detects isolated shadows that become nodule candidates, extracts a volume of interest that includes shadow candidates, and divides the volume of interest into rectangular regions. It expresses nodules and blood vessels in three‐dimensional geometric models of spheres and cylinders, and lists a number of object models having high probabilities of existing in each rectangular region. It then generates a combination of object models by assembling the physical models. It formulates the relationships between each rectangular region, anatomical verifications of the object model combinations and the degree of agreement between observed CT images and object model combinations in the framework of a three‐dimensional Markov random field model, and computes the probability that a shadow candidate is a nodule and the probability that the shadow candidate is not a nodule. A shadow candidate is determined to be a nodule if the probability of it being a nodule is high, while it is determined to be normal otherwise. The proposed scheme is applied to actual CT images of 10‐mm slice intervals to show its efficacy. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(8): 82–95, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10453
Change of reaction time according to the presentation of cues about the direction of saccade in a delayed saccade task
Authors: Tsunoda Yoshiaki , Nakamura Kiyohiko 
Published: May 2004

AbstractThe preparation of saccade is examined on the basis of the reaction time in a delayed saccade task. The position of the visual stimulus presentation as the target of saccade is varied stochastically and then the signal indicating the start of the saccade is presented with a delay. In other words, a task is considered in which the direction of saccade is indicated before indicating the start of the saccade. We investigate how the preparation of the saccade progresses in the delay period following the indication of the direction. The following results were obtained in our experiments. (1) The reaction time decreases with increasing delay period. (2) The reaction time does not decrease but remains almost constant when the delay exceeds a certain value. (3) Even if the direction of saccade is known, the reaction time is decreased when the target is presented. As a conclusion, it is suggested that the saccade is prepared in the delay period based on the information concerning the saccade direction, since the reaction time decreases with increasing delay. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(8): 66–71, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10512
Odds ratios for a continuous outcome variable without dichotomizing
Authors: Moser Barry Kurt , Coombs Laura P. 
Published: May 2004

AbstractThe loss of information from dichotomizing a continuous outcome is well documented in the literature. One advantage of dichotomizing is that it allows estimation of odds ratio parameters through a logistic regression analysis. The objective of this paper is to develop a new estimator of the same odds ratio parameters through regression analysis on the original continuous outcome without the inherent loss of information caused by dichotomizing. Through a mathematical, asymptotic development the relative sample sizes required to attain a specified power when testing the odds ratio parameter are compared for the dichotomizing procedure and the proposed approach. The comparison highlights the substantial sample size savings attained by the proposed approach, particularly for large values of the odds ratio parameter and for small proportions of dichotomized successes or failures. In a Monte Carlo simulation the variances and absolute biases of the two odds ratio estimators and the length of their respective confidence intervals again demonstrate the improvement attained by the proposed approach. In addition, coverage probabilities of the confidence intervals of the proposed approach converge quickly to the nominal levels. The cost savings due to the reduction in required sample size when using this method make it a very attractive study design and analysis tool for medical researchers. Copyright © 2004 John Wiley & Sons, Ltd.
Displaying dependence graphs: a hierarchical approach
Authors: Balmas F. 
Published: May 2004

AbstractWe present a method to extract and handle data and control dependences of programs, which we represent as simplified system dependence graphs. Ordinary dependence graphs contain too many nodes and edges for them to be easily comprehended, even for medium sized programs. That is why we propose decomposing programs into a hierarchy of groups for which the corresponding dependence graphs are likely to be of manageable size. In order to realize this, we first implement a tool that builds this hierarchy and stores it in a database. Then a graphical interface provides means to browse the hierarchy, to visualize the dependences of each group, to possibly refine the proposed hierarchy and to annotate nodes or groups.This paper introduces our approach for dependence graph handling, it describes our tool for graph exploration and discusses the results we obtained with a set of real‐world programs. Copyright © 2004 John Wiley & Sons, Ltd.