bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of intervertebral disc degeneration by high‐resolution magic angle spinning (HR‐MAS) spectroscopy
Authors: Keshari Kayvan R. , Zektzer Andrew S. , Swanson Mark G. , Majumdar Sharmila , Lotz Jeffrey C. , Kurhanewicz John 
Published: February 2005

AbstractThe goal of this study was to determine the ability of high‐resolution magic angle spinning (HR‐MAS) NMR spectroscopy to distinguish different stages of intervertebral disc degeneration (IVDD). 17 discs were removed from human cadavers and analyzed them using 1D and 2D (total correlation spectroscopy (TOCSY)) 1H HR‐MAS spectroscopy, and T1 and T2 relaxation time measurements to determine the chemical composition and changes in chemical environment of discs with increasing levels of degeneration (Thompson grade). Among the significant findings were that spectra were very similar for samples taken from annular and nuclear regions of discs, and that visually apparent changes were observed in the spectra of the annular and nuclear samples from discs with increasing Thompson grade. Area ratios of the N‐acetyl to choline (Cho) regions, and Cho to carbohydrate (Carb) regions of the spectra allowed us to discriminate between discs of increasing Thompson grade with minimal overlap of individual ratios. Changes in T1 and T2 relaxation times of the chemical constituents of disc spectra were not significantly correlated to the degree of degeneration. The results of this study support the feasibility of using in vivo spectroscopy for detecting chemical changes associated with disc degeneration. Magn Reson Med 53:519–527, 2005. © 2005 Wiley‐Liss, Inc.
Oxygen‐sensitive contrast in blood for steady‐state free precession imaging
Authors: Dharmakumar Rohan , Hong Juimiin , Brittain Jean H. , Plewes Donald B. , Wright Graham A. 
Published: February 2005

AbstractSteady‐state free precession (SSFP) methods have gained widespread recognition for their ability to provide fast scans at high signal‐to‐noise ratio. This paper demonstrates that such methods are also capable of reflecting functional information, particularly blood oxygenation state. It is well known that SSFP signals show substantial sensitivity to small off‐resonance frequency variations. However, that mechanism cannot explain the oxygen‐sensitive contrast in blood that was observed with steady‐state methods using phase‐cycled radiofrequency pulses. From theoretical and experimental models it is demonstrated that the mechanism responsible for such contrast originates from the motion of spins through local field inhomogeneities in and around deoxygenated red blood cells. In addition, this work shows that it is critical to choose the scan parameters carefully for robust oxygen‐sensitive contrast. Finally, it is demonstrated that it is possible to build a quantitative model that incorporates the Luz–Meiboom model, which had been used in the past to estimate quantitative measures of vascular blood oxygen levels. It is envisioned that this method could be instrumental in real‐time imaging focused on detecting diseases where the oxygen state of blood is impaired. Magn Reson Med 53:574–583, 2005. © 2005 Wiley‐Liss, Inc.
Free breathing 3D balanced FFE coronary magnetic resonance angiography with prolonged cardiac acquisition windows and intra‐RR motion correction
Authors: Stehning C. , Börnert P. , Nehrke K. , Dössel O. 
Published: February 2005

AbstractA shortcoming of today's coronary magnetic resonance angiography (MRA) is its low total scan efficiency (<5%), as only small well‐defined fractions of the respiratory (50%) and cardiac (10%) cycle are used for data acquisition. These precautions are necessary to prevent blurring and artifacts related to respiratory and cardiac motion. Hence, scan times range from 4 to 9 min, which may not be tolerated by patients. To overcome this drawback, an ECG‐triggered, navigator‐gated free breathing radial 3D balanced FFE sequence with intra‐RR motion correction is investigated in this study. Scan efficiency is increased by using a long cardiac acquisition window during the RR interval. This allows the acquisition of a number of independent k‐space segments during each cardiac cycle. The intersegment motion is corrected using a self‐guided epicardial fat tracking procedure in a postprocessing step. Finally, combining the motion‐corrected segments forms a high‐resolution image. Experiments on healthy volunteers are presented to show the basic feasibility of this approach. Magn Reson Med 53:719–723, 2005. © 2005 Wiley‐Liss, Inc.
Extraction of overt verbal response from the acoustic noise in a functional magnetic resonance imaging scan by use of segmented active noise cancellation
Authors: Jung Kwan‐Jin , Prasad Parikshit , Qin Yulin , Anderson John R. 
Published: February 2005

AbstractA method to extract the subject's overt verbal response from the obscuring acoustic noise in an fMRI scan is developed by applying active noise cancellation with a conventional MRI microphone. Since the EPI scanning and its accompanying acoustic noise in fMRI are repetitive, the acoustic noise in one time segment was used as a reference noise in suppressing the acoustic noise in subsequent segments. However, the acoustic noise from the scanner was affected by the subject's movements, so the reference noise was adaptively adjusted as the scanner's acoustic properties varied in time. This method was successfully applied to a cognitive fMRI experiment with overt verbal responses. Magn Reson Med 53:739–744, 2005. © 2005 Wiley‐Liss, Inc.
129Xe spectra from the heads of rats with and without ligation of the external carotid and pterygopalatine arteries
Authors: Nakamura Kazuhiro , Kondoh Yasushi , Wakai Atsushi , Kershaw Jeff , Wright David , Kanno Iwao 
Published: February 2005

AbstractAfter rats inhaled hyperpolarized 129Xe gas, in vivo spectra from their heads revealed a dominant peak around 195 ppm, another easily resolvable peak near 189 ppm, a broad peak around 210 ppm, and two minor peaks around 198 ppm and 192 ppm. However, the source of each peak remains controversial. To further study the origin of each peak, we compared spectra obtained from the heads of normal rats with spectra taken from the heads of rats that had undergone ligation of the external carotid (ECA) and pterygopalatine (PPA) arteries, the major feeding vessels of nonbrain tissue in the rat head. The amplitude of the peak at around 189 ppm was greatly reduced in the ECA/PPA‐ligated rats, while the peak around 195 ppm persisted. We conclude that the signal that originates from the rat brain after inhalation of 129Xe gas is overwhelmingly dominated by the single resonance at 195 ppm. Magn Reson Med 53:528–534, 2005. © 2005 Wiley‐Liss, Inc.
Shutter‐speed analysis of contrast reagent bolus‐tracking data: Preliminary observations in benign and malignant breast disease
Authors: Li Xin , Huang Wei , Yankeelov Thomas E. , Tudorica Alina , Rooney William D. , Springer Charles S. 
Published: February 2005

AbstractThe standard pharmacokinetic model applied to contrast reagent (CR) bolus‐tracking (B‐T) MRI (dynamic‐contrast‐enhanced) data makes the intrinsic assumption that equilibrium transcytolemmal water molecule exchange is effectively infinitely fast. Theory and simulation have suggested that this assumption can lead to significant errors. Recent analyses of animal model experimental data have confirmed two predicted signature inadequacies: a specific temporal mismatch with the B‐T time‐course and a CR dose‐dependent underestimation of model parameters. The most parsimonious adjustment to account for this aspect leads to the “shutter‐speed” pharmacokinetic model. Application of the latter to the animal model data mostly eliminates the two signature inadequacies. Here, the standard and shutter‐speed models are applied to B‐T data obtained from routine human breast examinations. The signature standard model temporal mismatch is found for each of the three invasive ductal carcinoma (IDC) cases and for each of the three fibroadenoma (FA) cases studied. It is effectively eliminated by use of the shutter‐speed model. The size of the mismatch is considerably greater for the IDC lesions than for the FA lesions, causing the shutter‐speed model to exhibit improved discrimination of malignant IDC tumors from the benign FA lesions compared with the standard model. Furthermore, the shutter‐speed model clearly reveals focal “hot spots” of elevated CR perfusion/permeation present in only the malignant tumors. Magn Reson Med 53:724–729, 2005. © 2005 Wiley‐Liss, Inc.
SAVANT analysis of the microelectronics and photonics testbed solar cell data
Authors: Walters Robert J. , Summers G. P. , Messenger S. R. , Morton T. L. 
Published: February 2005

AbstractAn analysis of solar array data from the Microelectronic and Photonic Testbed (MPTB) space experiment is presented. The data are analyzed using the displacement damage dose (Dd) methodology developed by the US Naval Research Laboratory (NRL) as implemented in the Solar Array Verification and Analysis Tool (SAVANT). SAVANT is a WindowsTM‐based computer code that predicts the on‐orbit performance of a solar cell in a specified Earth orbit. The predicted solar cell performance produced by the SAVANT code are compared with the measured on‐orbit data. In addition, the calculated data are compared with onboard dosimeter measurements. The results allow both a validation of the SAVANT code and a comparison of the space environment models with measured on‐orbit data. The results show the models to match the measured data within a factor of 2. Published in 2005 by John Wiley & Sons, Ltd.
Moving past cultural homogeneity: Suggestions for comparisons of students' educational outcomes in the United States and China
Authors: Peverly Stephen T. 
Published: February 2005

AbstractBased on observations of the Chinese educational system in the summer of 2002, I argue that comparisons of the performance of students in the United States and China, and by implication, of students in the United States and other East Asian countries, have been too homogeneous. I discuss four variables that could be included in future research between the United States and China (and by implication, in all U.S./East Asian research): urban versus rural education (SES), public versus private schools, China's ethnic minorities, and the education of boys and girls. Recommendations for future research are provided. © 2005 Wiley Periodicals, Inc. Psychol Schs 42: 241–249, 2005.
The coming‐of‐age of China's single‐child policy
Authors: Mcloughlin Caven S. 
Published: February 2005

AbstractChina's one‐child policy is now 25 years of age—the officially sanctioned age for marriage by men in the People's Republic of China. A significant proportion of those now about to enter their child‐bearing years are themselves the product of the first generation of one‐child homes. This article reviews the history of the single‐child policy, with specific regard to the forces that initiated it as a national imperative and which today appear to sustain its widespread acceptance by the Chinese peoples. This article considers the circumstances leading to the implementation of the single‐child policy, the development of incentives for compliance and penalties for noncompliance, information reflecting representative data‐based analyses of outcomes from the policy, and the present situation and scenarios that might lead to a revisitation of this policy. Impressions and data gathering were conducted through conversation with individuals from all social strata in six locales in the People's Republic of China and were contrasted with similar exploratory visits from 10 and 15 years ago. © 2005 Wiley Periodicals, Inc. Psychol Schs 42: 305–313, 2005.
Solution NMR structure of the SH3 domain of human nephrocystin and analysis of a mutation‐causing juvenile nephronophthisis
Authors: le Maire Albane , Weber Thomas , Saunier Sophie , Broutin Isabelle , Antignac Corinne , Ducruix Arnaud , Dardel Frédéric 
Published: February 2005

AbstractHuman nephrocystin is a protein associated with juvenile NPH, an autosomal recessive, inherited kidney disease responsible for chronic renal failure in children. It contains an SH3 domain involved in signaling pathways controlling cell adhesion and cytoskeleton organization. The solution structure of this domain was solved by triple resonance NMR spectroscopy. Within the core, the structure is similar to those previously reported for other SH3 domains but exhibits a number of specific noncanonical features within the polyproline ligand binding site. Some of the key conserved residues are missing, and the N‐Src loop exhibits an unusual twisted geometry, which results in a narrowing of the binding groove. This is induced by the replacement of a conserved Asp, Asn, or Glu residue by a Pro at one side of the N‐Src loop. A systematic survey of other SH3 domains also containing a Pro at this position reveals that most of them belong to proteins involved in cell adhesion or motility. A variant of this domain, which carries a point mutation causing NPH, was also analyzed. This change, L180P, although it corresponds to a nonconserved and solvent‐exposed position, causes a complete loss of the tertiary structure. Similar effects are also observed with the L180A variant. This could be a context‐dependent effect resulting from an interaction between neighboring charged side‐chains. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Dependence of magnetic properties on the growth conditions of MnGaN grown by rf N plasma molecular beam epitaxy
Authors: Haider Muhammad B. , Constantin Costel , Al‐Brithen Hamad , Caruntu Gabriel , O'Connor Charles J. , Smith Arthur R. 
Published: February 2005

AbstractMnGaN has been grown by radio frequency N plasma‐assisted molecular beam epitaxy. MnGaN samples were grown on MOCVD GaN(0001)/sapphire(0001) at substrate temperature of 550 °C under different Ga/N flux ratios leading to 4 different growth regimes: N‐rich, slight metal‐rich, metal‐rich, and Ga‐rich. It is found that in the case of MnGaN, Mn incorporation and hence magnetic properties clearly depend on the growth conditions. Briefly, it is found that the N‐rich conditions give a sample with much larger magnetization compared to the other samples. Slight metal‐rich and metal‐rich grown samples have very little magnetization. Finally, Ga‐rich grown samples have intermediate level of magnetization. Possible origins of the magnetization are discussed. Ga‐rich magnetization is attributed to accumulates, but N‐rich magnetization is attributed to carrier‐mediated ferromagnetism and/or ferromagnetism due to clusters. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Grazing‐incidence diffraction strain analysis of a laterally patterned Si wafer treated by focused Ge and Au ion beam implantation
Authors: Grenzer J. , Pietsch U. , Bischoff L. 
Published: February 2005

AbstractStrain analysis of a laterally patterned Si‐wafer was carried out utilizing X‐ray grazing‐incidence diffraction with synchrotron radiation. The lateral patterning was done by focused ion beam implantation using an ion source of liquid AuGeSi alloy. Samples were prepared by either 35 keV Au+ ions (dose: 0.2, 2 × 1014 cm–2) or 70 keV Ge++ ions (dose: 8 × 1014 cm–2). It was shown that due to implantation a periodical defect structure is created consisting of both implanted and not implanted stripes. The evaluated depth distribution of defects within the implanted stripes corresponds to that obtained by TRIM calculation. The induced strain distribution, however, shows no periodicity. This can be explained by an overlap of the strain fields created in each implanted stripe. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic properties of Cu substituted NdMn2Si2 intermetallics
Authors: Elmali A. , Dincer I. , Elerman Y. , Ehrenberg H. , Fuess H. 
Published: February 2005

AbstractThe structure and magnetic properties of NdMn2–xCuxSi2 (0.2 ≤ x ≤ 1) were studied by X‐ray powder diffraction and magnetization measurements. In this study, we investigate the variations in the magnetic properties of NdMn2–xCuxSi2 as a function of Cu concentration by examing the evolution of the features in the temperature dependence of the magnetization. Earlier neutron diffraction experiments showed that the ferromagnetic Mn planes are ordered antiparallel along the c‐axis below 380 K and the Nd sublattice orders at 33 K in NdMn2Si2. The ordering of the Nd sublattice reconfigures the ordering in Mn sublattice and leads to ferromagnetic ordering. With increasing amount of Cu, the Curie temperature has a maximum value of 120 K at x = 0.7 and decreases for the samples with x ≥ 0.8. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Advances in photoreflectance characterisation of photonic (resonant‐cavity) and transistor epiwafers
Authors: Murtagh M. E. , Ward S. , Kelly P. V. 
Published: February 2005

AbstractAdvances in the application of non‐contact photoreflectance (PR) spectroscopy to the characterisation of epiwafer device materials are presented. The study examines both vertical cavity surface emitting laser (VCSEL) and heterojunction bipolar transistor (HBTs) device structures. Emphasis is placed on the technologically important applications of VCSEL device material characterisation, for which PR offers the only true non‐destructive testing capability, as well as upon the measurement of electric fields in device epiwafers for rf application transistors such as HBTs. This paper demonstrates the application of non‐destructive and rapid techniques for evaluation and control of compound semiconductor materials for both VCSEL and HBT technology. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Control of Al‐doping in 4H–SiC homo‐epitaxial layers grown with a HMDS/TMA/P mixture
Authors: Sartel C. , Soulière V. , Zielinski M. , Monteil Y. , Camassel J. , Smith L. , Rushworth S. 
Published: February 2005

AbstractWe report on the growth of thin, aluminium doped, homo‐epitaxial layers of 4H–SiC using a threefold mixture of purified hexamethyldisilane (HMDS) admixted with propane (P) and trimethylaluminium (TMA). The growth has been performed in an AP‐CVD, cold wall, vertical reactor in which the growth of 4H–SiC layers using HMDS admixed with propane has been well demonstrated. To control, as a function of the growth parameters, the amount of aluminium incorporated in the epitaxial layers SIMS, C(V) and Raman experiments were done. They show that good quality p‐type epitaxial layers can be grown, up to a final aluminium concentration of about 2 × 1019 at cm–3. Comparing with the more standard gas system silane/TMA/P, we have found that there is no significant difference. The total amount of Al incorporated is about the same and, in both cases, the incorporation starts to be limited when the growth temperature reaches 1500 °C. In both cases, also, the C/Si ratio and the growth rate influence the aluminium concentration. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Control of epitaxial layers grown on 4H–SiC: from 3C microcrystalline inclusions to type II quantum well structures
Authors: Juillaguet S. , Balloud C. , Soulière V. , Sartel C. , Camassel J. , Y. Monteil  
Published: February 2005

AbstractWe report the results of a series of LTPL (Low Temperature PhotoLuminescence) investigation performed on n‐type, non‐intentionally doped, 4H–SiC samples. We focus on the defect structure introduced by a	growth fault in the stacking sequence. We treat the fault as a 3C quantum well embedded in a 4H–SiC matrix and use a simple 2‐dimensional approximation to deduce the extent of the lattice perturbation associated with a given defect. We show that the intrinsic type‐II nature of the band alignment, combined with the effect of the spontaneous polarization, must result in a double bound‐exciton signature per well, which is resolved for the first time. The comparison with experimental results confirms also that, after a relatively small critical layer thickness, the back conversion from cubic to hexagonal remains an unsolved problem. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A method for quantitative determination of deuterium content in biological material
Authors: He Yihui , Tang Caihua , Mao Jiangsen , Liu Ziyang , Huang Weixing , Mao Zi'an 
Published: February 2005

AbstractA method was developed for quantitative determination of deuterium incorporated into live organisms or biological macromolecules. The deuterated biological material was mixed with a bovine serum albumin (BSA) supporter to make a homogeneous sample for which the δD value (vs. VSMOW) was analyzed using a dual‐inlet gas isotope mass spectrometer. The method is described in detail, and the equation for calculation of deuterium content is presented, i.e., C = 1/500 × k × RVSMOW × C × 106 ppm. Deuterated hepatitis A virus (HAV) RNA and BSA were systematically investigated. The results demonstrate that the method is capable of direct measurement of deuterium content, and is highly repeatable and reliable with a standard deviation of ±3‰. It is stressed that the quantity of deuterated sample required is extremely small as a result of using BSA as supporter. The method may be applied in many fields, and has the strengths of simplicity, relative cheapness, and robustness. Copyright © 2005 John Wiley & Sons, Ltd.
Hardware‐accelerated protein identification for mass spectrometry
Authors: Alex Anish T. , Dumontier Michel , Rose Jonathan S. , Hogue Christopher W. V. 
Published: February 2005

AbstractAn ongoing issue in mass spectrometry is the time it takes to search DNA sequences with MS/MS peptide fragments (see, e.g., Choudary et al., Proteomics 2001; 1: 651–667.) Search times are far longer than spectra acquisition time, and parallelization of search software on clusters requires doubling the size of a conventional computing cluster to cut the search time in half. Field programmable gate arrays (FPGAs) are used to create hardware‐accelerated algorithms that reduce operating costs and improve search speed compared to large clusters. We present a novel hardware design that takes full spectra and computes 6‐frame translation word searches on DNA databases at a rate of approximately 3 billion base pairs per second, with queries of up to 10 amino acids in length and arbitrary wildcard positions. Hardware post‐processing identifies in silico tryptic peptides and scores them using a variety of techniques including mass frequency expected values. With faster FPGAs protein identifications from the human genome can be achieved in less than a second, and this makes it an ideal solution for a number of proteome‐scale applications. Copyright © 2005 John Wiley & Sons, Ltd.
Characterization of NiB amorphous alloys with x‐ray photoelectron and secondary ion mass spectroscopy
Authors: Diplas S. , Lehrmann J. , Jørgensen S. , Våland T. , Watts J. F. , Taftø J. 
Published: February 2005

AbstractAmorphous NiB alloys with nominal compositions 30 at.% B and 50 at.% B were produced via electrodeposition on pure Ni polycrystalline substrates. The surfaces of the alloys were characterized with x‐ray photoelectron spectroscopy (XPS) and dynamic secondary ion mass spectrometry (DSIMS). Information on the compositional variation with depth was acquired with XPS both non‐destructively, in angle‐resolved mode (ARXPS), and destructively with argon ion etching, as well as with DSIMS. Boron oxide dominates the outermost surface of the alloys. Its presence also in the bulk of the alloys is attributed to oxidation during processing, whereas the presence of hydrogen detected with SIMS is attributed to adsorption occurring during processing. The Auger parameter concept and information from the primary and secondary structure of the XPS spectrum were employed to probe the electronic changes occurring upon alloying. It is suggested that the main electronic changes occurring are hybridization of the Ni spd states with the B sp states and an apparent increase of the electron density around the Ni sites. Copyright © 2005 John Wiley & Sons, Ltd.