bluuebunny/crossref_metadata_2025_split huggingface dataset:
Leptin, adiponectin, resistin, and ghrelin – Implications for inflammatory bowel disease
Authors: Karmiris Konstantinos , Koutroubakis Ioannis E. , Kouroumalis Elias A. 
Published: March 2008

AbstractInflammatory bowel disease (IBD) is characterized by anorexia, malnutrition, altered body composition, and development of mesenteric white adipose tissue (WAT) hypertrophy. Increasing evidence suggests that adipokines synthesized either in WAT or in immune cells, are involved in these manifestations of IBD. Among adipokines leptin, adiponectin and resistin hold a fundamental role while the role of ghrelin in inflammation is not well established. Preliminary studies have shown overexpression of leptin, adiponectin, and resistin in mesenteric WAT of patients with Crohn's disease (CD) and significant alterations of circulating serum levels of these adipokines in IBD. It has also been demonstrated that intestinal inflammation causes an increase in endogenous ghrelin production. In animal models of intestinal inflammation, existing data suggest that leptin, adiponectin, and resistin are pivotal mediators of inflammation. Interesting therapeutic interventions based on these data have been suggested. A specific role for hypertrophic WAT has also been implicated in CD. Further efforts with experimental and clinical studies are needed to better understand the role of adipokines in IBD.
Prebiotics, synbiotics and inflammatory bowel disease
Authors: Steed Helen , Macfarlane George T. , Macfarlane Sandra 
Published: March 2008

AbstractThe normal colonic microflora is intimately involved in the aetiology of inflammatory bowel diseases (IBD) such as ulcerative colitis (UC) and Crohn's disease (CD). These conditions are often refractile to conventional treatments involving the employment of anti‐inflammatory and immunosuppressant drugs, and this has led to a search for alternative therapies based on the use of probiotics, prebiotics and synbiotics. The majority of investigations in this area have been done with probiotics, and while there is increasing interest in the abilities of prebiotics and synbiotics to control the symptoms of IBD, very few randomised controlled trials have been reported. Although the results have been variable, human and animal studies have demonstrated that in many circumstances, these functional foods can alter the composition of the colonic microbiota, reduce inflammatory processes in the gut mucosa, and have the potential to induce disease remission. More work is needed to understand the effects of prebiotics and synbiotics on microbial communities in the gut, and their interactions with the host's immune system.
Dielectric properties of silicon in terahertz wave region
Authors: Li JiuSheng , Li JianRui 
Published: March 2008

AbstractBy using backward‐wave oscillator system, the terahertz dielectric properties of p‐type silicon were tested in the frequency range extending from 0.68 to 0.85 THz. The refractive indices, the power absorption coefficient, and the dielectric functions of various resistivity p‐type silicons were measured and compared. The variation of the refractive index of the ultra‐resistivity silicon was less than 3%, ranging from 3.037 to 3.125, but the absorption coefficient of the ultra‐resistivity silicon showed very different frequency‐dependent behaviors, ranging from 3.25 × 10−3 cm−1 to 2.90 × 10−5 cm−1, within the investigated frequency range. The ultra‐resistivity silicon will be a good candidate material for terahertz transmission waveguide with ultra‐low loss. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1143–1146, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23313
Design of novel miniaturized fractal‐shaped branch‐line couplers
Authors: Chen Wen‐Ling , Wang Guang‐Ming 
Published: March 2008

AbstractAlthough miniaturized and fractal‐shaped branch‐line couplers have been reported by many researchers, their operating bandwidth are narrowed and shifted greatly, thus the application of these techniques were limited. In this article, we presented an exact design technique to obtain compact and fractal‐shaped branch‐line couplers for a given frequency. As an example, novel fractal‐shaped branch‐line couplers operated at 2.4 GHz using Koch fractal shapes of different iteration orders have been designed successfully, and the designed couplers all operated at the designed frequency and achieved a maximal 81.8% size reduction. And furthermore, the operating frequency and its bandwidth are virtually unaltered. The proposed method is verified by the measurement results. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1198–1201, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23316
Measurement of AC current using a superstructure fiber grating
Authors: Cheng Chin‐Hsing , Chen Ming‐Hsien , Liu Wen‐Fung 
Published: March 2008

AbstractIn the power industry, current must be measured for metering and protection purposes. For such measurements, this article demonstrates an optical fiber sensor using a superstructure fiber grating (SFG) to measure AC current. The sensor head is based on superstructure fiber grating encapsulated in a polymer‐half‐field metal cylinder embedded a magnetic material. The sensor detects force when it is attracted by the induced magnetic force created by the solenoid along one radial direction only and responds to an axial force on the magnetic rod attached to the round plate, creating an axial attraction on the SFG. The SFG is composed of a fiber Bragg grating (FBG) and a long period grating (LPG). Therefore, variations in attractive force and temperature cause variations in SFG center‐wavelength. Thus, the sensor can be used to measure attracting forces and temperature effects simultaneously. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1168–1171, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23317
Study on high‐temperature and high‐pressure measurement by using metal‐coated FBG
Authors: Shen Ren‐Sheng , Zhang Jin , Wang Yan , Teng Rui , Wang Ben‐Yu , Zhang Yu‐Shu , Yan Wei‐Ping , Zheng Jie , Du Guo‐Tong 
Published: March 2008

AbstractMetal‐coated fiber Bragg grating (MFBG) sensor was proposed to measure high‐temperature and high‐pressure condition. Metal‐coated layer of FBG improved bonding performance between metal material substrate and sensor protected as well as prolonged the lifespan of the FBG sensor. By optimized and designed thin‐wall copper cylinder structure and soldered MFBG on this, we had measured high‐temperature and high‐pressure environments. This sensor can measure the pressure range from 0 to 40 MPa. Its correlative coefficient reached 99.95% and its sensitivity was 0.0493 nm/MPa, which was about 19 times than normal Fiber Bragg Grating. Using a thermostat, a good linearity of temperature characteristic of this structure was obtained and its correlative coefficient reached 99.904%. Temperature had been measured range from 50 to 240°C. Considering FBG intrinsic advantage, it has been applied in harsh environments such as oil‐well. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1138–1140, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23319
A quantitative study on the low frequency breakdown of EFIE
Authors: Qian Zhi Guo , Chew Weng Cho 
Published: March 2008

AbstractA quantitative study is presented for the low frequency breakdown of the electric‐field integral equation (EFIE) with the Rao–Wilton–Glisson basis function. The low frequency limit is ascertained hereby. Numerical experiments validate the conclusion. The line testing method is also compared with the Galerkin testing to dispel the misconception in the literature. The study thus provides a guideline for the application of EFIE in the full‐field regime. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1159–1162, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23324
Characterization of microstrip transmission lines at IR frequencies—Modeling, fabrication and measurements
Authors: Mandviwala Tasneem A. , Lail Brian A. , Boreman Glenn D. 
Published: March 2008

AbstractWe report the complete characterization of microstrip lines at an infrared frequency of 28.3 THz (10.6‐μm wavelength) through modeling, fabrication, and measurement. The transmission‐line parameters of interest can not be directly measured at infrared frequencies—the only measurable quantity is the voltage response of the antenna‐coupled bolometric sensor. We validate the computational approach for transmission‐line parameters by verifying the computed and measured response of the antenna connected to microstrip lines of different lengths. This also allows us to extend these calculations to explore various configurations and identify design trends. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1232–1237, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23344
Optimization of printed ultra wide‐band antenna using microgenetic algorithm combined with FDTD
Authors: Jie Sheng , Yang Xue‐Xia , Sun Xiao‐Meng 
Published: March 2008

AbstractIn this article, a printed U‐type ultra wide‐band (UWB) antenna is designed for UWB communication using a microgenetic algorithm (MGA) in conjunction with the finite‐difference time‐domain (FDTD) method. A stepped microstrip configuration which improves the impedance bandwidth is optimized by using MGA and FDTD to achieve the UWB characteristics. The measured VSWR of the antenna is less than 2 from 3.1 GHz to 10.6 GHz. The proposed antenna has a good radiation characteristic by measurement and the simulated gain is between 3.3 and 6 dB. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1289–1292, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23358
A circular CPW‐fed slot antenna resonated by the circular loop for broadband circularly polarized radiation
Authors: Deng I‐Chung , Ke Qing‐Xiang , Lin Ren‐Jie , King Yueh‐Tsu 
Published: March 2008

AbstractThe coplanar waveguide (CPW) fed circular slot antenna, resonated by the circular loop with a narrow opening, is designed for obtaining broadband circularly polarized (CP) radiation. The length of protruded signal strip (LS) is utilized to adjust the phase difference between two orthogonal field components in the circularly polarized waves. In this design, the proposed antenna has the minimum return loss of −56.5 dB at the frequency of 2.403 GHz. The impedance and 3 dB axial‐ratio bandwidths can reach up to 740 MHz or 33.3% and 390 MHz or 16.6%, respectively. In addition, the simulated results are about as good as those of the measured ones. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1423–1426, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23359
Particle swarm optimization application to microwave circuits
Authors: Ülker Sadık 
Published: March 2008

AbstractThis letter presents the concept of particle swarm optimization (PSO) technique applied to two sets of microwave circuits: microstrip coupler and single shunt stub matching circuit. The PSO technique that is applied to these two set of designs is tested and compared with simulation results. The results show that PSO is an efficient method for solving these kinds of problems and can be applied for the design of microwave circuits. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1333–1336, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23369
Multilayer inphase power divider for UWB applications
Authors: Abbosh A. M. 
Published: March 2008

AbstractA multilayer inphase power divider with ultra wideband behavior is presented. It has a compact size with an overall dimension of 20 mm × 30 mm. The proposed divider utilizes broadside coupling via a multilayer microstrip/slot configuration. The simulated and measured results show that the proposed device has 3.3 ± 0.3 dB insertion loss, about 20 dB return loss, and 10 dB isolation across the frequency band 3.1‐10.6 GHz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1402–1405, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23379
A low power X‐band CMOS differential VCO
Authors: Jang Sheng‐Lyang , Huang S.‐S. , Wu Sheng‐Chien , Lee Chien‐Feng , Juang M.‐H. 
Published: March 2008

AbstractThis article proposes a 12 GHz low power differential voltage‐controlled oscillator (VCO) based on single‐ended Colpitts oscillators. The differential VCO uses two single‐ended Colpitts VCOs coupled by a pair of pMOS cross‐coupled transistors and a transformer inductor. The differential VCO was fabricated in the TSMC 0.18‐nm CMOS process, it oscillates from 11.46 GHz to 12.45 GHz, and the power consumption is 2.76 mW at the supply voltage of 1.2 V. The measured phase noise at 1‐MHz offset is g110.95 dBc/Hz at the oscillation frequency of 12.42 GHz. The power consumption of the VCO is 2.3 mA when the supplied voltage is 1.2 V. The figure of merit of the VCO is −188.43 dBc/Hz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1389–1392, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23388
Tunable single‐to‐dual channel wavelength conversion of picosecond pulses based on four‐wave mixing in microstructure fibers
Authors: Zhang Xia , Ren Xiaomin , Xu Yongzhao , Wang Zinan , Huang Yongqing 
Published: March 2008

AbstractAll optical wavelength conversion between picosecond pulses based on four‐wave mixing (FWM) is experimentally demonstrated in 80‐m dispersion‐flatted high nonlinear microstructure fibers (MF). The pulsed signal with 10‐GHz repetition rate and 1.6‐ps pulse width is used as pump wave. In the experiments, both down‐ and up‐conversion are obtained in this type of wavelength converter. Moreover, tunable single‐to‐dual channel wavelength conversion is experimentally observed. The experiment results imply that it is possible to realize tunable single‐to‐multiple channel wavelength conversion. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1453–1455, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23398
Application of the tree‐cotree splitting for improving matrix conditioning in the full‐wave finite‐element analysis of high‐speed circuits
Authors: Lee Shih‐Hao , Jin Jian‐Ming 
Published: March 2008

AbstractIn this study the tree‐cotree splitting technique is applied for improving the finite‐element matrix conditioning for the analysis of high‐speed circuits. A well‐known issue is that at low frequencies a full‐wave solver yields less accurate solutions and may even breakdown due to ill‐conditioned system matrices. To enhance the capability and reliability of the conventional finite element method in broadband full‐wave analyses, we apply the tree‐cotree splitting to edge elements to account for the decoupling between the electric and magnetic fields at low frequencies, which is the main reason for the low‐frequency problem. The algorithm for finding a minimum spanning tree when there exist wave ports, lumped ports, or for a PEC‐free structure are described. Besides, a model order reduction method, called the solution space projection, is applied for a fast broadband analysis. We further propose an expansion to available solution bases for a better approximation to low‐frequency fields, so that a simulation can be extended to extremely low frequencies. The application is focused on the simulation of high‐speed circuits, of which both low and high frequency characteristics are of equal importance. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1476–1481, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23403
Bent inverted‐F antenna for WLAN units
Authors: Hristov H. D. , Carrasco H. , Feick R. 
Published: March 2008

AbstractWe show how a wire inverted‐F antenna can be made more compact without significant alteration of its impedance and radiation characteristics. Two modified inverted‐F antennas, one in air and another with solid dielectric casing, were computer‐simulated for the 2.4‐GHz band and their input match loss and bandwidth were validated experimentally. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1505–1510, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23405
An on‐site “SAR” evaluation using interpolation and plane‐wave decomposition
Authors: Saidi F. , Lautru D. , Gati A. , Wong M. F. , Nicolas E. , Jacquin F. , Wiart J. , Fouad‐Hanna V. 
Published: March 2008

AbstractTwo efficient techniques are investigated for the evaluation of the human exposure to electromagnetic fields in terms of the on‐site assessment of the specific absorption rate (SAR) using interpolation techniques and plane‐wave decomposition. These methods allow evaluating, in an optimal manner, the induced electromagnetic field and the SAR in a human tissue using both the measurements and calculation resulting in the alleviation of imposed constraints on them. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1501–1505, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23406
Radiation from transversely slotted waveguide
Authors: Kim Yang H. , Eom Hyo J. , Zeong Jong W. 
Published: March 2008

AbstractThe problem of radiation from transversely slotted waveguides is solved by using Fourier transform and mode‐matching techniques. The solution for narrow slot widths is represented in fast convergent series. Good agreement is observed between our theory and other results. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1547–1549, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23416
Collinear printed array antenna
Authors: Thomas K. George , Lenin N. 
Published: March 2008

AbstractA novel high gain printed dipole array antenna for omni directional coverage is presented. The dipoles are electromagnetically fed by planar slots, formed on a 50 Ω microstrip transmission line. The impedance characteristics and radiation patterns of the antenna are analyzed numerically with finite element method and compared with the measurement. The unbalanced feed point of the antenna is fed directly with a small co‐axial cable. The antenna demonstrates good impedance and pattern bandwidth of 300 MHz from 2.25–2.55 GHz and is suitable for ISM band/WLAN operation. The optimum impedance matching can be achieved by increasing the width of the 50 Ω line around the feed point and thereby altering feed point impedance. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1582–1584, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23423
Investigation of return loss for large numbers of bonding wires by FDTD method
Authors: Chen Hsing‐Yi , Su Chieh‐Pin 
Published: March 2008

AbstractThe finite‐difference time domain (FDTD) model is validated first by comparing the simulation results of return losses for 1, 7, and 15 bonding wires fabricated on a test board with those obtained by the HFSS software. After checking its accuracy, the FDTD method is used to investigate the return loss for bonding wire arrays with numerous geometrical parameters. From simulation results, it is found that the return loss of bonding wires can be improved by using multiple wires placed in parallel in bonding wire arrays. It is also found that operation frequency shifts of bonding wire arrays can be achieved by changing the wire numbers in bonding wire arrays. It is also reveled that the return loss of bonding wire structures is a function of the bonding wire geometry, such as the spacing between adjacent wires, wire number, wire height above the substrate, and wire length. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1575–1579, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23425
Radiation patterns of microstrip leaky‐wave antenna with parasitic elements
Authors: Li YuanXin , Xue Quan , Yung Edward Kai‐Ning , Long YunLiang 
Published: March 2008

AbstractA microstrip leaky‐wave antenna (MLWA) with parasitic elements is presented in this letter. The short MLWA is the basic element, and two microstrip patches with a short‐circuit edge worked as the parasitic elements. The main lobe scans from 66° to 42° when operating frequency increases from 5.9 to 6.9 GHz. In contrast to the conventional MLWA, the reflected wave of the short MLWA (about two wavelengths) with parasitic elements is suppressed 12 dB at 6.9 GHz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1565–1567, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23428
An internal modified rectangular loop antenna for DVB‐H applications
Authors: Choi Il H. , Lee Jung N. , Park Jong K. , Yim Byoung J. 
Published: March 2008

AbstractAn internal modified rectangular loop antenna with two open stubs for digital video broadcasting‐handheld (DVB‐H) terminals is proposed. The antenna consists of the modified rectangular loop, the two open stubs, and a four element matching. We have used the meandering technique to increase the electrical length of the antenna and two open stubs for tuning the high frequency edge of the DVB‐H band. To more improve the impedance bandwidth of the DVB‐H frequency band (470–702 MHz), a four element matching circuit is used. All simulations are carried out by Ansoft HFSS software. Moreover, by fabricating the antenna, the simulations results are verified by experimental data. Good antenna performances such as radiations patterns and antenna gains over the operating frequency band have been observed. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1592–1595, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23440
A novel printed dual‐monopole array with antenna selection circuit for adaptive MIMO systems
Authors: Li Zhengyi , Wang Xuan , Du Zhengwei , Gong Ke 
Published: March 2008

AbstractAntenna selection is an effective method to achieve reconfigurable antenna array for adaptive MIMO systems. In this article, a novel printed dual‐monopole array with antenna selection circuit for adaptive MIMO systems is proposed. By four pin‐diodes embedded in the feeding network, the array can operate as a dual‐antenna array and also work as a single antenna while the other is terminated to a matched lumped resistor. When the array operates as a dual‐antenna array the measured bandwidths cover the UMTS band with acceptable isolation. When it works as a single antenna the measured bandwidth still covers the UMTS band. From the measured radiation patterns, it is obvious that the radiation patterns of the selected monopole change little whether the other monopole is selected or not. Accordingly, the system can achieve antenna selection scheme to adapt to the time‐varying channel conditions. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1584–1590, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23442