bluuebunny/crossref_metadata_2025_split huggingface dataset:
The experimental study of a polarization orthogonal single‐longitudinal‐mode distributed Bragg reflector fiber laser
Authors: Jian‐Hua Luo , Bo Liu , Yu‐Wen Lan , Shu‐Zhong Yuan , Li‐Wei Wang 
Published: March 2008

AbstractIn this article, we reported a polarization orthogonal single‐longitudinal‐mode distributed Bragg reflector (DBR) fiber laser. The laser operated robustly in single longitudinal mode and dual polarizations with frequency difference of 976.93 MHz. This laser has simple structure as well as frequency adjustable. It can be used in a wide range of communication, sensor, and spectroscopic applications. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1658–1660, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23454
Application of multisection recursive convolution in 3D FETD‐FABC simulations
Authors: Cai Yong , Mias Christos 
Published: March 2008

AbstractThe multisection recursive convolution (MS‐RC) methodology is successfully applied to the finite element time domain floquet absorbing boundary condition modeling of doubly periodic structures. It is shown that late time instability can be delayed by improving the accuracy of RC and it can be effectively avoided by employing extrapolation. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1651–1657, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23455
32‐GHz dual‐termination coupled CPW bandpass filter on HR‐SI
Authors: Li Xi , Shi Yan‐Ling , Ding Yan‐Fang , Chen Da‐Wei , Shen Di 
Published: March 2008

AbstractBandpass filter is an important device in portable communication and other RF systems. A dual‐termination coupled coplanar waveguide (CPW) bandpass filter (BPF) has been designed by HFSS. This dual‐termination coupled structure improves the coupling capacitances between the central metal and the matching transmission lines so that the insertion loss can be reduced. The filter has been fabricated on a high resistivity silicon substrate (ρ ≥ 1000 Ω cm) with 1 μm SiO2. It has −2.16‐dB low insertion loss at peak transmission of about 32 GHz. This filter shows good s‐parameter characteristics and it is attractive for RF ICs. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1705–1706, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23464
The application of motion compensation of ISAR image for a moving target in radar target recognition
Authors: Shin Seung Yong , Myung Noh Hoon 
Published: March 2008

AbstractInverse synthetic aperture radar (ISAR) is an imaging technique which generates a two‐dimensional (2D) high resolution image of a target. In general, ISAR image is often adequate to discriminate various missiles, military aircraft, and civilian aircraft and so on. However, if the target has complicated motion such as pitching, yawing, rolling, and maneuvering, ISAR image is not enough to classify among these targets. This article presents high resolution techniques for application in motion compensation of ISAR image for a radar backscattered signal from the moving target. A simple Fourier Transform (FT) is employed to obtain ISAR image for a moving target, then the image is usually blurred. These images blurring problem can be solved with the time‐frequency transform. In this article, we compensate the translational motion using the minimum entropy method (MEM) and rotational motion using the Gabor Wavelet Transform (GWT) for a moving target. To show the performances of each technique, we use backscattered field data of the ideal point scatterers and the simulated MIG‐25 to obtain motion compensated ISAR image and display the resolution of motion compensated ISAR images. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1673–1678, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23466
A compact internal UWB antenna for wireless USB dongle application
Authors: Shin Jaewoong , Hong Seokjin , Choi Jaehoon 
Published: March 2008

AbstractThis article presents a compact internal ultra‐wideband antenna for wireless universal serial bus dongle application. The proposed antenna has a simple configuration and is easy to implement by bending a simple metal plate. To widen the impedance bandwidth, the proposed antenna has a vertical patch with a bevel structure and a horizontal patch with a narrow slit. The proposed antenna satisfies the 10‐dB return loss requirement over the frequency band of 2.9–10.85 GHz (7.95 GHz) and so easily covers the UWB band of 3.1–10.6 GHz. The effects of the system ground plane on the impedance matching of antenna are studied experimentally. The detailed design of the proposed antenna is described, and experimental results including radiation patterns and peak gains are presented. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1643–1646, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23468
Reducing correlated noise in fMRI data
Authors: de Zwart Jacco A. , Gelderen Peter van , Fukunaga Masaki , Duyn Jeff H. 
Published: March 2008

AbstractThe sensitivity of functional MRI (fMRI) in detecting neuronal activation is dependent on the relative levels of signal and noise in the time‐series data. The temporal noise level within a single voxel is generally substantially higher than the intrinsic NMR (thermal) noise, and the noise is often correlated between voxels. This work introduces and evaluates a method that allows fMRI sensitivity improvement by reduction of these correlated noise sources. The method allows model‐free estimation of the correlated noise from brain regions not activated by the functional paradigm using a short (1–2 min) reference scan. A single regressor representing this noise‐source estimate is added to the design matrix used in the data analysis. Results obtained from five volunteers show an average t‐score improvement of 11.3% and a 24.2% increase in the size of the activated area. Magn Reson Med 59:939–945, 2008. © 2008 Wiley‐Liss, Inc.
Improved image reconstruction for partial fourier gradient‐echo echo‐planar imaging (EPI)
Authors: Chen Nan‐kuei , Oshio Koichi , Panych Lawrence P. 
Published: March 2008

AbstractThe partial Fourier gradient‐echo echo planar imaging (EPI) technique makes it possible to acquire high‐resolution functional MRI (fMRI) data at an optimal echo time. This technique is especially important for fMRI studies at high magnetic fields, where the optimal echo time is short and may not be achieved with a full Fourier acquisition scheme. In addition, it has been shown that partial Fourier EPI provides better anatomic resolvability than full Fourier EPI. However, the partial Fourier gradient‐echo EPI may be degraded by artifacts that are not usually seen in other types of imaging. Those unique artifacts in partial Fourier gradient‐echo EPI, to our knowledge, have not yet been systematically evaluated. Here we use the k‐space energy spectrum analysis method to understand and characterize two types of partial Fourier EPI artifacts. Our studies show that Type 1 artifact, originating from k‐space energy loss, cannot be corrected with pure postprocessing, and Type 2 artifact can be eliminated with an improved reconstruction method. We propose a novel algorithm, that combines images obtained from two or more reconstruction schemes guided by k‐space energy spectrum analysis, to generate partial Fourier EPI with greatly reduced Type 2 artifact. Quality control procedures for avoiding Type 1 artifact in partial Fourier EPI are also discussed. Magn Reson Med 59:916–924, 2008. © 2008 Wiley‐Liss, Inc.
Differentiation between benign and malignant breast lesions detected by bilateral dynamic contrast‐enhanced MRI: A sensitivity and specificity study
Authors: Jansen Sanaz A. , Fan Xiaobing , Karczmar Gregory S. , Abe Hiroyuki , Schmidt Robert A. , Newstead Gillian M. 
Published: March 2008

AbstractThe purpose of this study was to apply an empirical mathematical model (EMM) to kinetic data acquired under a clinical protocol to determine if the sensitivity and specificity can be improved compared with qualitative BI‐RADS descriptors of kinetics. 3D DCE‐MRI data from 100 patients with 34 benign and 79 malignant lesions were selected for review under an Institutional Review Board (IRB)‐approved protocol. The sensitivity and specificity of the delayed phase classification were 91% and 18%, respectively. The EMM was able to accurately fit these curves. There was a statistically significant difference between benign and malignant lesions for several model parameters: the uptake rate, initial slope, signal enhancement ratio, and curvature at the peak enhancement (at most P = 0.04). These results demonstrated that EMM analysis provided at least the diagnostic accuracy of the kinetic classifiers described in the BI‐RADS lexicon, and offered a few key advantages. It can be used to standardize data from institutions with different dynamic protocols and can provide a more objective classification with continuous variables so that thresholds can be set to achieve desired sensitivity and specificity. This suggests that the EMM may be useful for analysis of routine clinical data. Magn Reson Med 59:747–754, 2008. © 2008 Wiley‐Liss, Inc.
Anatomically constrained reconstruction from noisy data
Authors: Haldar Justin P. , Hernando Diego , Song Sheng‐Kwei , Liang Zhi‐Pei 
Published: March 2008

AbstractNoise is a major concern in many important imaging applications. To improve data signal‐to‐noise ratio (SNR), experiments often focus on collecting low‐frequencyk‐space data. This article proposes a new scheme to enable extendedk‐space sampling in these contexts. It is shown that the degradation in SNR associated with extended sampling can be effectively mitigated by using statistical modeling in concert with anatomical prior information. The method represents a significant departure from most existing anatomically constrained imaging methods, which rely on anatomical information to achieve super‐resolution. The method has the advantage that less accurate anatomical information is required relative to super‐resolution approaches. Theoretical and experimental results are provided to characterize the performance of the proposed scheme. Magn Reson Med 59:810–818, 2008. © 2008 Wiley‐Liss, Inc.
Slice‐selective images of free radicals in mice with modulated field gradient electron paramagnetic resonance (EPR) imaging
Authors: Sato‐Akaba Hideo , Abe Haruhiko , Fujii Hirotada , Hirata Hiroshi 
Published: March 2008

AbstractContinuous wave (CW) electron paramagnetic resonance (EPR) imaging can be used to obtain slice‐selective images of free radicals without measuring three‐dimensional (3D) projection data. A method that incorporated a modulated magnetic field gradient (MFG) was combined with polar field gradients to select a slice in the subject noninvasively. The slice‐selective in vivo EPR imaging of triarylmethyl radicals in the heads of live mice is reported. 3D surface‐rendered images were successfully obtained from slice‐selective images. In the experiment in mice, a slice thickness of 1.8 mm was achieved. Magn Reson Med 59:885–890, 2008. © 2008 Wiley‐Liss, Inc.
Multinuclear NMR investigation of probe construction materials at 9.4T
Authors: Marjanska Malgorzata , Waks Matt , Snyder Carl J. , Vaughan J. Tommy 
Published: March 2008

AbstractThis work investigates probe construction materials for their signal contribution to ultrashort echo time spectroscopy and imaging. 1H, 13C, and 31P spectra were obtained at a field strength of 9.4 T for 16 materials considered for use in probe and holder design and construction. Four of the materials were found to be suited for the construction of NMR probes, housing of RF coils, and holders for in vivo experiments. Magn Reson Med 59:936–938, 2008. © 2008 Wiley‐Liss, Inc.
Fast parallel spiral chemical shift imaging at 3T using iterative SENSE reconstruction
Authors: Mayer Dirk , Kim Dong‐Hyun , Spielman Daniel M. , Bammer Roland 
Published: March 2008

AbstractSpiral chemical shift imaging (CSI) is a fast CSI technique that simultaneously encodes 1D spectral and 2D spatial information. Therefore, it potentially allows one to perform a 2D‐CSI experiment in a single shot. However, for most applications, limitations on maximum gradient strength and slew rate make multiple excitations necessary in order to achieve a desired spectral bandwidth. In this work we reduce the number of spatial interleaves and, hence, the minimum total measurement time of spiral CSI by using an iterative sensitivity encoding reconstruction algorithm which utilizes complementary spatial encoding afforded by the spatially inhomogeneous sensitivity profiles of individual receiver coils. The performance of the new method was evaluated in phantom and in vivo experiments. Parallel spiral CSI produced maps of brain metabolites similar to those obtained using conventional gridding reconstruction of the fully sampled data with only a small decrease in time‐normalized signal‐to‐noise ratio and a small increase in noise for higher acceleration factors. Magn Reson Med 59:891–897, 2008. © 2008 Wiley‐Liss, Inc.
Robust H∞ control of an uncertain system via a strict bounded real output feedback controller
Authors: Petersen Ian R. 
Published: March 2008

AbstractThis paper presents a new approach to the robust H∞ control of an uncertain system via an output feedback controller that is both stable and has an H∞ norm strictly less than a specified value. The uncertain systems under consideration contain structured uncertainty described by integral quadratic constraints. The controller is designed to achieve absolute stabilization with a specified level of disturbance attenuation. The main result involves solving a state feedback version of the problem by solving an algebraic Riccati equation dependent on a set of scaling parameters. Then two further algebraic Riccati equations are solved, which depend on a further set of scaling parameters. The required controller is constructed from the Riccati solutions. Copyright © 2008 John Wiley & Sons, Ltd.
New ladder‐type conjugated polymer containing carbazole and fluorene units in backbone: Synthesis, optical, and electrochemistry properties
Authors: Wang Baoling , Shen Fangzhong , Lu Ping , Tang Shi , Zhang Wu , Pan Shiwei , Liu Meirong , Liu Linlin , Qiu Song , Ma Yuguang 
Published: March 2008

AbstractThis article describes the synthesis and characterization of a new ladder‐type poly (p‐phenylene) (LPFC) containing alkylcarbazole and dialkylfluorene units in backbone, and its optical and electrochemical properties as well as its light‐emitting device performance. LPFC shows the well‐defined structure, high molecular weights, excellent thermal stability, and good solubility in common organic solvents. And it also shows strongly blue emission (λmax = 465 nm) with quantum efficiency of 70% in solution, while its solid emission (λmax = 470 nm) is almost the same as its solution. Electrochemical studies show that the highest occupied molecular orbital (HOMO) energy levels of LPFC is up to 5.29 eV, which is significantly higher than that of LPPP without carbazole in backbone, indicating an enhanced ability of hole injection from anodes. Furthermore, the single layer light‐emitting device using LPFC as the active layer shows blue emission (λmax = 470 nm) with maximum luminescence of ∼ 2000 cd/m2 and maximum luminance efficiency of 0.43 cd/A. The attractive properties exhibited from new ladder‐type polymer establish LPFC as a good candidate for the potential application as transporting and emitting layer in polymeric light emitting diodes. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3120–3127, 2008
Simultaneous reversible addition fragmentation chain transfer and ring‐opening polymerization
Authors: Le Hellaye Maude , Lefay Catherine , Davis Thomas P. , Stenzel Martina H. , Barner‐Kowollik Christopher 
Published: March 2008

AbstractThe simultaneous ring‐opening polymerization (ROP) of ε‐caprolactone (ε‐CL) and 2‐hydroxyethyl methacrylate (HEMA) polymerization via reversible addition fragmentation chain transfer (RAFT) chemistry and the possible access to graft copolymers with degradable and nondegradable segments is investigated. HEMA and ε‐CL are reacted in the presence of cyanoisopropyl dithiobenzoate (CPDB) and tin(II) 2‐ethylhexanoate (Sn(Oct)2) under typical ROP conditions (T > 100 °C) using toluene as the solvent in order to lead to the graft copolymer PHEMA‐g‐PCL. Graft copolymer formation is evidenced by a combination of size‐exclusion chromatography (SEC) and NMR analyses as well as confirmed by the hydrolysis of the PCL segments of the copolymer. With targeted copolymers containing at least 10% weight of PHEMA and relatively small PHEMA backbones (ca. 5,000–10,000 g mol−1) the copolymer grafting density is higher than 90%. The ratio of free HEMA‐PCL homopolymer produced during the “one‐step” process was found to depend on the HEMA concentration, as well as the half‐life time of the radical initiator used. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3058–3067, 2008
Synthesis of a new diglycidylic Meldrum acid derivative and study of the curing with lanthanide triflates as initiators
Authors: González Lidia , Simokaitiene Jurate , Ramis Xavier , Salla Josep Maria , Mantecón Ana , Serra Angels 
Published: March 2008

AbstractA new epoxy resin derived from Meldrum acid (DGMA) was synthesized by a two steps synthetic procedure and structurally characterized by the usual spectroscopic techniques and elemental analysis. Ytterbium and lanthanum triflates were tested as cationic initiators to cure this resin and its mixtures with diglycidylether of bisphenol A (DGEBA) in several proportions. By FTIR‐ATR spectroscopy the evolution of the groups, which participate in the curing was followed. The evolution of the curing and the Tg of the materials were studied by differential scanning calorimetry and the kinetic parameters were calculated applying isoconversional procedures. Ytterbium triflate led to a quicker curing than lanthanum. The thermal stability of the materials obtained was evaluated by thermogravimetry and the higher thermal degradability of the materials containing DGMA was confirmed. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3088–3097, 2008
Analysis of multiple melting behavior of spherulites comprising ring‐band shell/ringless core in polymorphic poly(butylene adipate)
Authors: Woo E. M. , Yen Kai Cheng , Wu Ming Chien 
Published: March 2008

AbstractIn‐depth interpretation of ring‐banded spherulitic morphology, crystals, polymorphism, and complex melting behavior in poly(1,4‐butylene adipate) (PBA) were analyzed via a procedure of designing composite core‐shell spherulites, in which two lamellar patterns (ring‐band vs. ringless) were packed by subjecting to crystallization at two‐step temperature schemes with specific temperatures and times. By heating to 52 °C and holding at that temperature for 30 min annealing, the core can be stripped off by melting, and analysis specifically on the ring‐shell portion (with the ringless core stripped by controlled melting) proves that the highest melting peak (P4 at 55–57 °C) is likely associated with melting of the ring‐band lamellae. Furthermore, the unusually complex multiple melting in PBA can be attributed to all three widely proposed mechanisms: (1) multiple types of lamellae preexisting in crystallized PBA, (2) scan/heating induced remelting/reorganization, and (3) polymorphism of dual crystal cells. In addition, this study evidently shows that the extinction rings within the ring‐banded shell, regardless of alternate edge‐on and flat‐on mechanism or alternative origins, can be of all singly α‐crystal form, either initially or upon postheating temperature‐induced transformation. Thus, the type of crystal forms (α or β) in polymorphic PBA is mainly associated with temperature of crystallization (Tc = 28 or 35 °C), and not likely with lamellar orientation (flat‐on or edge‐on). © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 892–899, 2008
Investigation of the Correlations Between Nitro Group Charges and Some Properties of Nitro Organic Compounds
Authors: Zhang Chaoyang 
Published: March 2008

AbstractThe so‐called nitro group charge method (NGCM) is successfully established to investigate some properties of nitro compounds including the molecular stability measured by total energy (only for isomers), the bond lengths, bond dissociation energies (BDE), and the nitrating activities, in that the method considers the molecular structure. These properties are intrinsically and especially thermodynamically consistent with each other and can be well related qualitatively and even quantitatively with nitro group charges (QNitro). The correlations between QNitro and the properties are: (1) for nitro isomers, the more negative the average QNitro, the lower the total energy and the more stable is the isomer; (2) for any separate group of nitro compounds, the more negative QNitro, the shorter the R‐nitro bond length; (3) for the bond dissociation energy, more negative QNitro corresponds to a higher BDE of the R‐nitro bond; (4) by NGCM, the conditions, the reaction rates and the occurrence ratios of products of some nitration can be predicted and compared: the more negative QNitro of the product, the easier and faster the nitration, and the higher the occurrence ratio of the corresponding product.
Trypsin entrapped in poly(diallyldimethylammonium chloride) silica sol‐gel microreactor coupled to matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry
Authors: Xu Xuejiao , Wang Xiaoyan , Liu Yun , Liu Baohong , Wu Huiling , Yang Pengyuan 
Published: March 2008

AbstractAn enzyme‐immobilized capillary microreactor for rapid protein digestion and proteomics analysis is reported. The inner surface of the fused‐silica capillary was coated with poly(diallyldimethylammonium chloride) (PDDA)‐entrapped silica sol‐gel matrix, followed by assembly of trypsin onto the PDDA‐modified surface via electrostatic adsorption. The immobilization parameters such as PDDA content in the sol‐gel matrix, trypsin concentration and pH were investigated in detail. Protein samples including β‐casein, myoglobin and cytochrome c could be effectively digested and electrophoretically separated simultaneously in such a modified capillary. Just 2.26 ng (corresponding to 0.10–0.14 picomole) of sample was sufficient for on‐line capillary electrophoresis peptide mapping. The efficiency of the digestion was further demonstrated by digestion of a human liver cytoplasm sample and 253 proteins were identified in one unique run. Copyright © 2008 John Wiley & Sons, Ltd.