bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unconjugated bilirubin activates and damages microglia
Authors: Gordo Ana C. , Falcão Ana S. , Fernandes Adelaide , Brito Maria A. , Silva Rui F.M. , Brites Dora 
Published: April 2006

AbstractMicroglia are the resident immune cells of the brain and are the principal source of cytokines produced during central nervous system inflammation. We have previously shown that increased levels of unconjugated bilirubin (UCB), which can be detrimental to the central nervous system during neonatal life, induce the secretion of inflammatory cytokines and glutamate by astrocytes. Nevertheless, the effect of UCB on microglia has never been investigated. Hence, the main goal of the present study was to evaluate whether UCB leads to microglial activation and to the release of the cytokines tumor necrosis factor (TNF)‐α, interleukin (IL)‐1β, and IL‐6. Additionally, we investigated the effects of UCB on glutamate efflux and cell death. The results showed that UCB induces morphological changes characteristic of activated microglia and the release of high levels of TNF‐α, IL‐1β, and IL‐6 in a concentration‐dependent manner. In addition, UCB triggered extracellular accumulation of glutamate and an increased cell death by apoptosis and necrosis. These results demonstrate, for the first time, that UCB is toxic to microglial cells and point to microglia as an important target of UCB in the central nervous system. Moreover, they suggest that UCB‐induced cytokine production, by mediating cell injury, can further contribute to exacerbate neurototoxicity. Interestingly, microglia cells are much more responsive to UCB than astrocytes. Collectively, these data indicate that microglia may play an important role in the pathogenesis of encephalopathy during severe hyperbilirubinemia. © 2006 Wiley‐Liss, Inc.
A Study of the Photoorientation Phenomena in Cholesteric Polymer Systems Containing Photochromic Diarylethene Derivatives
Authors: Medvedeva Dasha , Bobrovsky Alexey , Boiko Natalia , Shibaev Valery , Shirinyan Valery , Krayushkin Mikhail 
Published: April 2006

AbstractSummary: Photoorientation processes in two cholesteric mixtures were studied. Mixture I contained a nematogenic phenylbenzoate homopolymer, a photochromic diarylethene dopant and a chiral dopant. Mixture II consisted of a binary comb‐shaped nematogenic copolymer with fluorescent perylene side groups and the same chiral and photochromic dopants. Irradiation of the mixtures with a polarized UV light did not induce photoorientation of the photoinduced “closed” form of the diarylethene dopant. However, the action of a polarized visible light on films of mixtures irradiated with UV light led to the appearance of dichroism. This phenomenon is associated with the photoselection process of the photochromic diarylethene molecules in the cholesteric matrix. An investigation of the kinetics of the photosensitized back photoreaction of the photochromic molecules in the cholesteric mixture showed that the polarized energy transfer from the fluorescent groups to the photochromic diarylethene dopant caused an increase in the photoselection rate. The thermal stability of dichroism in films of the mixtures was studied and it was shown that the disappearance of the dichroism of the diarylethene molecules occurred with a noticeable rate even at room temperature.Scheme of photophysical and photochemical processes under the indirect excitation of diarylethene molecules.imageScheme of photophysical and photochemical processes under the indirect excitation of diarylethene molecules.
Preparation of Spherical MgCl2‐Supported Late‐Transition Metal Catalysts for Ethylene Polymerization
Authors: Xu Renwei , Liu Dongbing , Wang Shibo , Mao Bingquan 
Published: April 2006

AbstractSummary: Facile and effective immobilization of late‐transition metal catalysts, 2,3‐bis‐(2,6‐diisopropylphenyl)butane diimine nickel(ii) dibromide (A) and 2,6‐bis‐[1‐(2,4,6‐trimethylphenylimino)ethyl]pyridine iron(ii) dichloride (B), for ethylene polymerization has been achieved, using spherical MgCl2 supports obtained by thermal dealcoholization of MgCl2 · 2.56C2H5OH instead of using supports of type MgCl2/AlRn(OEt)3−n. BET, XRD, IR, SEM, GPC, and DSC analyses indicate that the composition and structure of the supports, the activities of the supported catalysts, and the properties of the resultant polymers are strongly dependent on the dealcoholization temperature. The support SP‐3 obtained by treating MgCl2 · 2.56C2H5OH at 170 °C for 4 h is very effective for immobilizing late‐transition metal FeII and NiII catalysts. Compared with the corresponding unsupported homogeneous catalysts, a significant increase in activity is observed for the SP‐3 supported catalysts in ethylene polymerization, and the kinetics of polymerization is stable during the reaction process. In addition, replication of the support morphology is found in final polymers.Kinetic profiles of ethylene polymerization using SPC‐4, SPC‐5, and SPC‐6 under 1.0 MPa and at 70 °C.imageKinetic profiles of ethylene polymerization using SPC‐4, SPC‐5, and SPC‐6 under 1.0 MPa and at 70 °C.
Effect of Methylated Cyclodextrins on the Crystallization of Poly(3‐hydroxybutyrate)
Authors: Shin Kyung‐Moo , Dong Tungalag , He Yong , Inoue Yoshio 
Published: April 2006

AbstractSummary: The effects of methylated CDs, α‐ and β‐DMCD and α‐ and β‐TMCD on the crystallization behavior of P(3HB) have been investigated by employing DSC and polarized optical microscopy (POM). The crystallization and nucleation of P(3HB) was improved by an addition of appropriate amount of each methylated CD, while negative effect of miscible blend was observed when the amount of addition exceeds the optimum value for the maximum nucleating effect. β‐TMCD was shown to be the most effective for the enhancement of the P(3HB) crystallization, thought to be due to the possibility of IC formation with P(3HB).Plots of log{−ln [1 − X(t)]} versus log (t) for mixtures of P(3HB) with different CDs or talc, respectively.imagePlots of log{−ln [1 − X(t)]} versus log (t) for mixtures of P(3HB) with different CDs or talc, respectively.
Hollow Microstructured Polyaniline Prepared Using Cuprous Oxide Crystals as Templates
Authors: Zhang Zhiming , Deng Junying , Sui Jing , Yu Liangming , Wan Meixiang , Wei Yen 
Published: April 2006

AbstractSummary: Hollow octahedrons or microspheres of polyaniline (PANI) were successfully prepared using cuprous oxide (Cu2O) crystals as new templates in the presence of H3PO4 and ammonium peroxydisulfate as a dopant and an oxidant, respectively. Interestingly, the hollow octahedrons (in the reduced form with a conductivity of <10−8 S · cm−1) could transform into conductive microspheres (in the emeraldine salt form with a conductivity of 10−2 S · cm−1) when the [APS]/[An] ratio was changed from 1:1 to 2:1. Compared with the common template reported, Cu2O crystal is not only a new type of template in terms of both shape and quality, but also omits post‐treatment due to soluble Cu2+ formed by the reaction of Cu2O with APS during the polymerization process. The universality of Cu2O as a template to prepare microstructured PANI was proved by changing the morphology of the Cu2O crystal. It was found that the morphology, oxidation and protonation state of PANI microstructures prepared with octahedral Cu2O as the template were affected by the [Cu2O]/[An] and [APS]/[An] ratio due to the competitive reaction of aniline and Cu2O with APS.TEM images of PANI microspheres prepared using Cu2O as a template in the presence of H3PO4 and APS as a dopant and an oxidant.imageTEM images of PANI microspheres prepared using Cu2O as a template in the presence of H3PO4 and APS as a dopant and an oxidant.
Temperature and Pressure Dependence of the Free Volume in Polyisobutylene from Positron Lifetime and Pressure‐Volume‐Temperature Experiments
Authors: Kilburn Duncan , Wawryszczuk Jan , Dlubek Günter , Pionteck Jürgen , Häßler Rüdiger , Alam M. Ashraf 
Published: April 2006

AbstractSummary: The microstructure of the free volume and its temperature and pressure dependence in PIB were studied by PVT experiments and PALS. Employing the Simha–Somcynsky equation of state, the hole‐free volume fraction h and the specific free and occupied volumes, Vf  = hV and Vocc = (1 − h)V, respectively, and their expansivity and compressibility were calculated. From the PALS spectra analyzed using the LT9.0 software, the hole size distribution, the mean hole size 〈vh〉 and mean dispersion σh were calculated. From a comparison of 〈vh〉 with Vf, the hole density $N'_{\rm h}$ was obtained. It was found that PIB shows an unusual thermal expansion with glass‐like transitions at 210 K and 290 K (at 0 MPa). A similar behavior is observed for tan δ. It was found that at 296 K, 〈vh〉 decreases exponentially from 80 Å3 at 0.1 MPa to the extremely low value of 10 Å3 at 1 300 MPa. Starting from a fluctuation approach, the free‐volume fluctuations and the characteristic length scale (ξ) of dynamic heterogeneity of structural relaxation were estimated from σh. It was found that ξ increases from ≈1.5 nm to ≈1.9 nm when the temperature decreases from 293 K to the glass transition temperature Tg = 207 K (at 0 MPa) or the pressure increases from 0.1 MPa to 200 MPa (at 296 K).Fractional free volume and its mean fluctuation in PIB as determined from positron lifetime spectroscopy and PVT experiments analyzed with the Simha‐Somcynsky equation of state.imageFractional free volume and its mean fluctuation in PIB as determined from positron lifetime spectroscopy and PVT experiments analyzed with the Simha‐Somcynsky equation of state.
Hybrid Nanocomposite Films from Mono‐ and Multi‐Functional POSS Copolyacrylates in Miniemulsion
Authors: Castelvetro Valter , Ciardelli Francesco , De Vita Cinzia , Puppo Antonio 
Published: April 2006

AbstractSummary: The synthesis of aqueous dispersions of hybrid acrylic copolymer particles with either a monofunctional or a multifunctional polyhedral oligomeric silsesquioxane methacrylate comonomer has been performed by free radical heterophase polymerization. The miniemulsion process gives stable latexes, whereas the less controlled emulsion route results in colloidal instability of the products. The thermal and mechanical properties of the nanocomposite latex films have been preliminarily investigated.The nanocomposite latex particles based on hybrid copolyacrylates with highly dispersed POSS cages.magnified imageThe nanocomposite latex particles based on hybrid copolyacrylates with highly dispersed POSS cages.
Unbalanced line characterization for differential‐mode operation
Authors: Agili Sedig S. , Smith Stephen B. , Balasubramanian Vittal 
Published: April 2006

AbstractThis paper presents a theoretical model of the differential‐mode operation of unbalanced pairs and a method for its characterization. A differential pair having temporal imbalance is characterized using S‐parameter representations. Measurements in the frequency domain are performed. These measurements validate the proposed theoretical model. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1169–1174, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21549
The design of a dual polarized QUASI‐YAGI antenna array
Authors: Aghdam Karim Mohammad Pour , Kamarei Mahmoud 
Published: April 2006

AbstractIn this article, the design of a dual‐polarized quasi‐Yagi antenna array is described. The quasi‐Yagi elements are fed by broadband microstrip‐to‐CPS balun. A feeding circuit that contains multiple Lange couplers is designed to feed a 2 × 2 array of quasi‐Yagi elements. A 30% bandwidth (1.4 to 1.75 GHz) is achieved for VSWR and gain. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1164–1169, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21550
Design of microwave lumped and transversal bandpass filter with noise reduction
Authors: Choi Wai‐Wa , Tam Kam‐Weng , Martins Rui 
Published: April 2006

AbstractA simple design technique for a microwave lumped and transversal filter using constant‐k filter sections is presented. The noise figure can be suppressed by source degeneration inductors, which are added to the transversal element. The filter elements are analytically derived based on the specification and the noise minimization. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1161–1164, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21551
EMC internal patch antenna integrated with a U‐shaped shielding metal case for mobile device application
Authors: Su Chih‐Ming , Wong Kin‐Lu , Chen Brian , Yang Sam 
Published: April 2006

AbstractA novel integration design of a shorted patch antenna and a U‐shaped shielding metal case for application in a mobile communication device is presented. The shorted patch antenna is mounted within the dented portion of the U‐shaped shielding metal case, which can provide a coupling‐free space for accommodating electronic components such as the RF modules/circuitry and battery in the mobile device. Thus, in this case, the shorted patch antenna can operate as an internal antenna having an electromagnetic compatibility (EMC) property with nearby electronic components. In addition, with the proposed integration design, the shorted patch antenna is isolated from the two side edges of the system ground plane of the mobile device. Hence, it can be expected that the effects of the user's hand on the performances of the antenna will be suppressed. The proposed integration design applied to a smart phone for Universal Mobile Telecommunications System (UMTS, 1920–2170 MHz) operation is studied. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1157–1161, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21552
Near‐field data compression for the far‐field computation in FDTD
Authors: Pascaud Romain , Gillard Raphaël , Loison Renaud , Wiart Joe , Wong Man‐Faï 
Published: April 2006

AbstractThis paper presents a technique to compress the near‐field data required to compute the radiated fields using FDTD. This technique is applied to the study of a UWB planar diamond antenna. The results show a 99.8% gain in memory storage, while maintaining good accuracy: less than 1% error on the far‐field radiation patterns. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1155–1157, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21553
A 3.5‐GHz low‐noise amplifier for first‐generation ultra‐wideband radio
Authors: Yang Li , Liao Huailin , Zhang Guoyan , Huang Ru , Zhang Xing 
Published: April 2006

AbstractWe present a fully integrated low‐frequency (3.1–5‐GHz) ultra‐wideband (UWB) low‐noise amplifier (LNA) which implemented with a Jazz 0.35‐μm SiGe BiCMOS (peakfT60 GHz) process. The combination of common base and resistive shunt‐feedback stages was adopted as the main structure of the designed LNA. The measured maximum gain is 15.7 dB at 3.5 GHz with 0.6‐dB gain flatness over the whole operating bandwidth. And the minimum NF 3.8 dB is achieved at 4 GHz. The whole circuit including the bias circuit network consumes 7 mA with 3‐V supply and only occupies 0.65 × 0.9 mm. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1119–1123, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21554
A pattern‐reconfigurable microstrip antenna element
Authors: Lee K. W. , Rojas R. G. , Surittikul N. 
Published: April 2006

AbstractA novel radiation‐pattern‐reconfigurable circularly polarized microstrip antenna structure is presented. The measured results show that the antenna is able to provide a magnitude difference of more than 6 dB at 90° from broadside (in two principal planes) for the tangential (to the antenna surface) field component between the on and off states of the switches. Nonetheless, the vertical field component remains relatively unchanged. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1117–1119, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21555
Comparison between different models for the thin metallic substrate in multilayer microstrip structures
Authors: Zhang Lu , Song Jiming 
Published: April 2006

AbstractThe dispersive characteristics of multilayer microstrip structures with one thin metallic substrate are studied using the spectral‐domain approach. The numerical results of several approximate models are compared with that of the immittance approach as one exact model. The comparison shows that the widely used resistive sheet (R‐card) model is not appropriate to handle such structures over a broad frequency range. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1113–1117, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21556
New planar slotted‐patch resonator for miniaturized bandpass filter applications
Authors: Zhang Wen‐Jian , Li Zheng‐Fan 
Published: April 2006

AbstractA new planar slotted‐patch resonator is proposed for RF and microwave bandpass filter design. The novelty of the proposed resonator is that it can reduce the size of the filter significantly. It is found that the resonant frequency of the resonator is reduced (for example, by 61%). A dual‐mode filter operating at 2.39 GHz with 1.7% bandwidth and a three‐pole bandpass filter operating at 2.375 GHz with 8.8% bandwidth are designed and fabricated. The measured results agree very well with the full‐wave EM simulation. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1110–1112, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21557
MIMO space‐time coding for diffuse optical communication
Authors: Garfield Matt , Liang Chao , Kurzweg Timothy P. , Dandekar Kapil R. 
Published: April 2006

AbstractA multiple input, multiple output (MIMO) diffuse optical communications link is implemented and evaluated using a 2 × 2 Alamouti‐type space‐time coding scheme to increase link performance beyond that of single input, single output (SISO) and multiple input, single output (MISO) systems. We present a representative profile of received power versus distance, and comparative bit‐error probability performance. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1108–1110, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21558
Application of differential evolution algorithm to the modeling of laser diode nonlinearity in a radio‐over‐fiber network
Authors: Akdagli Ali , Yuksel M. Emin 
Published: April 2006

AbstractIn this paper, a simple and efficient method based on the differential evolution algorithm (DEA) is applied to the problem of modeling nonlinear characteristics of microwave intensity‐modulated laser diodes used in a radio‐over‐fiber (RoF) network. The performance of the presented method is experimentally evaluated using two different laser diodes. Very good agreement between the experimental measurement data and the model output indicates that the presented DEA based method may efficiently be used for accurate modeling and computation of IMD3 power levels of microwave intensity‐modulated GaAlAs diodes. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1130–1133, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21560
Low‐loss DPDT‐switch configuration with DGS structures
Authors: Thakur Jay Prakash , Ahn Ka‐Ram , Jung Myeong‐Sub , Jang Byoung‐Jun , Cho Hong‐Gu , Park Jun‐Seok 
Published: April 2006

AbstractIn this paper, a DPDT (Double‐Pole Double‐Throw) switch with defected ground structure (DGS) is newly proposed for transceiver systems. A biased varactor diode is introduced to control the on/off operation of the proposed switch. In order to confirm the validity of the switch, we design and implement the switch at the 2.45‐GHz frequency. It is designed specifically for antenna‐diversity switching for WLAN applications. The experimental results show very low insertion loss, excellent power handling, and high isolation performances. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1127–1130, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21561
In‐line beeline CMRC and applications to compact microstrip low‐pass filter
Authors: Zhang Fei , Gu Congying , Shi Lina , Li Chengfang , Gu Jiangzhong , Sun Xiaowei 
Published: April 2006

AbstractA novel beeline compact microstrip resonant cell (BCMRC) is proposed in this paper. Its photonic bandgap and slow‐wave effect are evaluated. The compact configuration presents superbroad stop‐band and improved slow‐wave characteristics. A low‐pass filter, consisting of three BCMRCs connected in series, is designed and fabricated. The filter has the advantages of low insertion loss in the passband, sharp, high, and wide rejection in the stop‐band, and compact size. Good agreement between the experimental and simulated results is achieved. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1125–1127, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21562
A novel high‐order time‐domain scheme for three‐dimensional Maxwell's equations
Authors: Huang Zhi‐Xiang , Sha Wei , Wu Xian‐Liang , Chen Ming‐Sheng 
Published: April 2006

AbstractA novel high‐order time‐domain scheme with a four‐stage optimized symplectic integrator propagator is presented for 3D electromagnetic scattering problems. The scheme is nondissipative and does not require more storage than the classical finite‐difference time‐domain (FDTD) method. The numerical results show the scheme has better stability and more efficiency than the classical FDTD method. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1123–1125, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21563
Analog characteristics of electroabsorption modulator for RF/optic conversion; RF gain and IMD3
Authors: Chung Yong‐Duck , Kang Young‐Shik , Choi Kwang‐Seong , Kim Sung‐Bock , Kim Jeha 
Published: April 2006

AbstractWe design and fabricate a traveling‐wave electroabsorption modulator for RF/optic conversion. The RF gain is measured with a simple RF/optic link. It is related to the optical transfer curve. The input optical power causes the change of the transfer curve so that the RF gain varies accordingly. The RF/optic conversion gain shows a close relationship with the slope efficiency of transfer curve. Linearity is also one of the important characteristics for analog applications. We evaluate the linearity of the module from the 3rd‐order intermodulation distortion (IMD3). © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1151–1155, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21564
Electromagnetic scattering from cylinder described by high‐order inhomogeneous impedance boundary conditions
Authors: Tezel Necmi Serkan , Paker Selçuk 
Published: April 2006

AbstractIn this study, the electromagnetic scattering from a high‐order inhomogeneous impedance cylinder is investigated. The method presented in this paper is based on the series representation of incident and scattering fields. The inhomogeneous‐surface impedance functions are also expressed by terms of Fourier series. By using the boundary condition on the surface of the cylinder, a series equation is obtained. This equation is reduced the matrix equation by using the orthogonal properties of the Fourier expansion functions and unknown mode coefficients can be calculated. The obtained results are compared with those obtained using the method of moments (MoM) for 1st‐order inhomogeneous‐surface impedance cylinder and good agreements are observed. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1148–1151, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21565