bluuebunny/crossref_metadata_2025_split huggingface dataset:
T2mapping of hip articular cartilage in healthy volunteers at 3T: A study of topographic variation
Authors: Watanabe Atsuya , Boesch Chris , Siebenrock Klaus , Obata Takayuki , Anderson Suzanne E. 
Published: July 2007

AbstractPurposeTo perform baseline T2mapping of the hips of healthy volunteers, focusing on topographic variation, because no detailed study has involved hips. T2mapping is a quantitative magnetic resonance imaging (MRI) technique that evaluates cartilage matrix components.Materials and MethodsHips of 12 healthy adults (six men and six women; mean age = 29.5 ± 4.9 years) were studied with a 3.0‐Tesla MRI system. T2measurement in the oblique‐coronal plane used a multi‐spin‐echo (MSE) sequence. Femoral cartilage was divided into 12 radial sections; acetabular cartilage was divided into six radial sections, and each section was divided into two layers representing the superficial and deep halves of the cartilage. T2of these sections and layers were measured.ResultsFemoral cartilage T2was the shortest (–20° to 20° and –10° to 10°, superficial and deep layers), with an increase near the magic angle (54.7°). Acetabular cartilage T2in both layers was shorter in the periphery than the other parts, especially at 20° to 30°. There were no significant differences in T2between right and left hips or between men and women.ConclusionTopographic variation exists in hip cartilage T2in young, healthy adults. These findings should be taken into account when T2mapping is applied to patients with degenerative cartilage. J. Magn. Reson. Imaging 2007;26:165–171. © 2007 Wiley‐Liss, Inc.
Priming effects in soil size fractions of a podzol Bs horizon after addition of fructose and alanine
Authors: Ohm Heike , Hamer Ute , Marschner Bernd 
Published: July 2007

AbstractIt is well known that the addition of easily available substrates to soils can affect microbial activity and thus the mineralization of soil organic carbon (SOC). Up to now, little is known about the processes leading to these priming effects and which fractions of organic matter (OM) are affected. The objectives of this study were to determine if SOC associated with isolated soil size fractions showed different susceptibility to priming effects, whether these pools are easily depleted, or whether the amount of substrate addition affects the extent of priming effects. In an incubation experiment, the effect of the uniformly 14C‐labeled substrates fructose and alanine on the mineralization of the SOC of a Bs horizon of a Haplic Podzol was investigated. The soil sample was fractionated into the three soil size fractions sand, silt, and clay by a mild sonication followed by sieving and sedimentation. Additionally, nonfractionated soil of the horizon was included in the experiment. Every soil sample received four substrate additions repeated at weekly intervals with 3.325 μg substrate‐C (mg SOC)–1 and a final addition of 13.3 μg substrate‐C (mg SOC)–1 after 4 weeks. The respiration was determined hourly and 14CO2 was analyzed every 2, 4, and 7 d after the respective substrate addition. After 56 d, between 42% and 58% of the added substrates had been mineralized. Both substrates strongly increased the mineralization of the OM in all fractions (positive priming effects). The priming effects were always higher after the addition of the high substrate dose than during the first 4 weeks when four small doses were added. In general, the priming effects increased with decreasing particle size. Alanine generally caused higher priming effects than fructose in the soil size fractions (up to 280% vs. 231%, respectively). This indicates that alanine serves not only as an energy substrate but also as a N source and, thus, also promotes microbial growth. The strong priming effects in the silt and clay fraction (133% and 125% with fructose, 172% and 168% with alanine) showed, that not only the labile pool of OM is affected, but also a more stable pool characterized by higher 14C ages. We assume that the stability of the OM in these fractions is not only due to recalcitrance or to interactions with the minerals, but that it may also be caused by a substrate limitation of the degrading microorganisms.
Simulated consumer use of a battery‐powered, hand‐held, portable diode laser (810 nm) for hair removal: A safety, efficacy and ease‐of‐use study
Authors: Wheeland Ronald G. 
Published: July 2007

AbstractBackground and ObjectivesSafety, efficacy and ease‐of‐use of a hair removal diode laser for consumer use were evaluated.Study Design/Materials and MethodsThe treatment group consisting of 77 appropriate users measured safety and efficacy from three self‐administered treatments. The non‐treatment group consisting of 44 inappropriate users measured safety from delivery of a single laser pulse.ResultsThe mean hair reduction was 61% 3 weeks after the first treatment, 70% 3 weeks after the second treatment, 60% 1 month after the third treatment, 24% 2 months after the third treatment, 6% 3 months after the third treatment, 41% 6 months after the third treatment, 31% 9 months after the third treatment, and 33% 12 months after the third treatment. The only observed side effect for appropriate users was transient erythema.ConclusionsIn simulated consumer use, the laser was highly effective at removing hair with minimal side effects for appropriate users. Lasers Surg. Med. 39:476–493, 2007. © 2007 Wiley‐Liss, Inc.
Synthesis of Arborescent Copolymers by a One‐Pot Method
Authors: Yuan Zhongshun , Gauthier Mario 
Published: July 2007

AbstractA “grafting from” scheme was developed for the preparation of arborescent copolymers in one single reactor, by anionic copolymerization of styrene with 1,3‐diisopropenylbenzene and activation of the pendent isopropenyl moieties with sec‐butyllithium. Arborescent polystyrene‐graft‐poly(tert‐butyl methacrylate) copolymers were thus obtained by addition of tert‐butyl methacrylate to linear and G0 macroinitiators, respectively. Arborescent polystyrene‐graft‐[polystyrene‐block‐poly(2‐vinylpyridine)] copolymers were also synthesized by successive additions of styrene and 2‐vinylpyridine to the same macroinitiators. The copolymers were characterized by SEC‐MALLS and 1H NMR analysis.magnified image
Mass Ratio of CdS/Poly(ethylene oxide) Controlled Photoluminescence of One‐Dimensional Hybrid Fibers by Electrospinning
Authors: Wang Cheng , Yan Eryun , Sun Zhiyao , Jiang Zijiang , Tong Yanbin , Xin Yi , Huang Zonghao 
Published: July 2007

AbstractOne‐dimensional high‐quality CdS/poly(ethylene oxide) (PEO) hybrid nanoparticle‐polymer fibers were fabricated by an electrospinning method, followed by self‐assemble technologies with co‐fed H2S atmosphere at 60 °C. The structural and spectral information of the resulting hybrid nanofibers was characterized by field emission scanning electron microscopy, transmission electron microscopy, X‐ray photoelectron spectroscopy and X‐ray diffractometer. The diameters of CdS/PEO hybrid nanofibers ranged from 90 to 200 nm and the average dimension of CdS nanoparticle within fibers from 4 to 12 nm. An interesting aspect of the CdS/PEO nanofibers shown in photoluminescence spectra and fluorescence images is that the fluorescence peaks of CdS/PEO were shifted along with changing the mass ratio of CdS/Poly(ethylene oxide), and consequently the size and phase of nanocrystal CdS.magnified image
Ethylene‐Norbornene Copolymerization by New Titanium Complexes Bearing Tridentate Ligands. Sidearm Effects on Catalytic Activity
Authors: Gao Mingli , Wang Cong , Sun Xiuli , Qian Changtao , Ma Zhi , Bu Shizheng , Tang Yong , Xie Zuowei 
Published: July 2007

AbstractThe Ti complexes containing tridentate [O−NSR] (R = Me, iPr) ligands with alkylthio sidearms were prepared. The methylthio ether complex (R = Me shown in the Scheme) exhibits an excellent activity for copolymerization of ethylene with norbornene upon activation with MMAO, which is 10 times more active than the corresponding phenylthio one (R = Ph).magnified image
Development of a hybrid EPR/NMR coimaging system
Authors: Samouilov Alexandre , Caia George L. , Kesselring Eric , Petryakov Sergey , Wasowicz Tomasz , Zweier Jay L. 
Published: July 2007

AbstractElectron paramagnetic resonance imaging (EPRI) is a powerful technique that enables spatial mapping of free radicals or other paramagnetic compounds; however, it does not in itself provide anatomic visualization of the body. Proton magnetic resonance imaging (MRI) is well suited to provide anatomical visualization. A hybrid EPR/NMR coimaging instrument was constructed that utilizes the complementary capabilities of both techniques, superimposing EPR and proton‐MR images to provide the distribution of paramagnetic species in the body. A common magnet and field gradient system is utilized along with a dual EPR and proton‐NMR resonator assembly, enabling coimaging without the need to move the sample. EPRI is performed at ∼1.2 GHz/∼40 mT and proton MRI is performed at 16.18 MHz/∼380 mT; hence the method is suitable for whole‐body coimaging of living mice. The gradient system used is calibrated and controlled in such a manner that the spatial geometry of the two acquired images is matched, enabling their superposition without additional postprocessing or marker registration. The performance of the system was tested in a series of phantoms and in vivo applications by mapping the location of a paramagnetic probe in the gastrointestinal (GI) tract of mice. This hybrid EPR/NMR coimaging instrument enables imaging of paramagnetic molecules along with their anatomic localization in the body. Magn Reson Med 58:156–166, 2007. © 2007 Wiley‐Liss, Inc.
Whole‐heart coronary magnetic resonance angiography at 3 Tesla in 5 minutes with slow infusion of Gd‐BOPTA, a high‐relaxivity clinical contrast agent
Authors: Bi Xiaoming , Carr James C. , Li Debiao 
Published: July 2007

AbstractT1‐shortening contrast agents have been used to improve the depiction of coronary arteries with breath‐hold magnetic resonance angiography (MRA). The spatial resolution and coverage are limited by the duration of the arterial phase of the contrast media passage. In this study we investigated the feasibility of acquiring free‐breathing, whole‐heart coronary MRA during slow infusion of the contrast media (0.3 ml/s) for prolonged blood signal enhancement time. Ultrashort TR (3 ms) and parallel data acquisition were used to allow the whole‐heart MRA in approximately 5 min. A newly approved gadolinium (Gd)‐based high T1 relaxivity contrast agent, gadobenate dimeglumine ([Gd‐BOPTA]2–), was used and coronary MRA was performed on a whole‐body 3 Tesla (T) system to improve the signal‐to‐noise ratio (SNR). Results from eight volunteers demonstrate that this coronary MRA method is capable of imaging the whole heart in 4.5 ± 0.6 min. Major coronary arteries are well depicted with high SNR (42.4 ± 12.5) and contrast‐to‐noise ratio (CNR; 27.1 ± 7.6). Magn Reson Med 58:1–7, 2007. © 2007 Wiley‐Liss, Inc.
In vivo 13carbon metabolic imaging at 3T with hyperpolarized 13C‐1‐pyruvate
Authors: Kohler S.J. , Yen Y. , Wolber J. , Chen A.P. , Albers M.J. , Bok R. , Zhang V. , Tropp J. , Nelson S. , Vigneron D.B. , Kurhanewicz J. , Hurd R.E. 
Published: July 2007

AbstractWe present for the first time dynamic spectra and spectroscopic images acquired in normal rats at 3T following the injection of 13C‐1‐pyruvate that was hyperpolarized by the dynamic nuclear polarization (DNP) method. Spectroscopic sampling was optimized for signal‐to‐noise ratio (SNR) and for spectral resolution of 13C‐1‐pyruvate and its metabolic products 13C‐1‐alanine, 13C‐1‐lactate, and 13C‐bicarbonate. Dynamic spectra in rats were collected with a temporal resolution of 3 s from a 90‐mm axial slab using a dual 1H‐13C quadrature birdcage coil to observe the combined effects of metabolism, flow, and T1 relaxation. In separate experiments, spectroscopic imaging data were obtained during a 17‐s acquisition of a 20‐mm axial slice centered on the rat kidney region to provide information on the spatial distribution of the metabolites. Conversion of pyruvate to lactate, alanine, and bicarbonate occurred within a minute of injection. Alanine was observed primarily in skeletal muscle and liver, while pyruvate, lactate, and bicarbonate concentrations were relatively high in the vasculature and kidneys. In contrast to earlier work at 1.5T, bicarbonate was routinely observed in skeletal muscle as well as the kidney and vasculature. Magn Reson Med 58:65–69, 2007. © 2007 Wiley‐Liss, Inc.
Perfusion mapping with multiecho multishot parallel imaging EPI
Authors: Newbould Rexford D. , Skare Stefan T. , Jochimsen Thies H. , Alley Marcus T. , Moseley Michael E. , Albers Gregory W. , Bammer Roland 
Published: July 2007

AbstractEcho‐planar imaging (EPI) is the standard technique for dynamic susceptibility‐contrast (DSC) perfusion MRI. However, EPI suffers from well‐known geometric distortions, which can be reduced by increasing the k‐space phase velocity. Moreover, the long echo times (TEs) used in DSC lead to signal saturation of the arterial input signal, and hence to severe quantitation errors in the hemodynamic information. Here, through the use of interleaved shot acquisition and parallel imaging (PI), rapid volumetric EPI is performed using pseudo‐single‐shot (ss)EPI with the effective T blur and susceptibility distortions of a multishot EPI sequence. The reduced readout lengths permit multiple echoes to be acquired with temporal resolution and spatial coverage similar to those obtained with a single‐echo method. Multiecho readouts allow for unbiased R mapping to avoid incorrect estimation of tracer concentration due to signal saturation or T1 shortening effects. Multiecho perfusion measurement also mitigates the signal‐to‐noise ratio (SNR) reduction that results from utilizing PI. Results from both volunteers and clinical stroke patients are presented. This acquisition scheme can aid most rapid time‐series acquisitions. The use of this method for DSC addresses the problem of signal saturation and T1 contamination while it improves image quality, and is a logical step toward better quantitative MR PWI. Magn Reson Med 58:70–81, 2007. © 2007 Wiley‐Liss, Inc.
Fast spin‐echo triple‐echo dixon (fTED) technique for efficientT2‐weighted water and fat imaging
Authors: Ma Jingfei , Son Jong Bum , Zhou Yuxiang , Le‐Petross Huong , Choi Haesun 
Published: July 2007

AbstractPreviously published fast spin‐echo (FSE) implementations of a Dixon method for water and fat separation all require multiple scans and thus a relatively long scan time. Further, the minimum echo spacing (esp), a time critical for FSE image quality and scan efficiency, often needs to be increased in order to bring about the required phase shift between the water and fat signals. This work proposes and implements a novel FSE triple‐echo Dixon (fTED) technique that can address these limitations. In the new technique, three raw images are acquired in a single FSE scan by replacing each frequency‐encoding gradient in a conventional FSE with three consecutive gradients of alternating polarity. The timing of the three gradients is adjusted by selecting an appropriate receiver bandwidth (RBW) so that the water and fat signals for the three corresponding echoes have a relative phase shift of −180°, 0°, and 180°, respectively. A fully automated postprocessing algorithm is then used to generate separate water‐only and fat‐only images for each slice. The technique was implemented with and without parallel imaging. We demonstrate that the new fTED technique enables both uniform water/fat separation and fast scanning with uncompromised scan parameters, including applications such asT2‐weighted separate water and fat imaging of the abdomen during breath‐holding. Magn Reson Med 58:103–109, 2007. © 2007 Wiley‐Liss, Inc.
Synthesis and properties of a well‐defined glycopolymer via living radical polymerization
Authors: Miura Yoshiko , Koketsu Daisuke , Kobayashi Kazukiyo 
Published: July 2007

AbstractA well‐defined glycopolymer was synthesized to investigate its properties. The glycopolymer was obtained with a narrow polydispersity by nitroxide‐mediated radical polymerization of styrene carrying acetylated lactose and by the subsequent deprotection. The cylindrical structure and helical conformation of the polymer were measured by circular dichroism (CD) spectra. The affinities of the polymers towards lectins depended on the degree of polymerization (DP), and the polymers with higher DP showed stronger affinity. Copyright © 2007 John Wiley & Sons, Ltd.
Influence of organic modifiers on morphology and crystallization of poly(ϵ‐caprolactone)/synthetic clay intercalated nanocomposites
Authors: Kiersnowski Adam , Gutmann Jochen S. , Pigłowski Jacek 
Published: July 2007

Abstractε‐caprolactone was polymerized in the presence of neat montmorillonite or organomontmorillonites to obtain a variety of poly(ε‐caprolactone) (PCL)‐based systems loaded with 10 wt % of the silicates. The materials were thoroughly investigated by different X‐ray scattering techniques to determine factors affecting structure of the systems. For one of the nanocomposites it was found that varying the temperature in the range corresponding to crystallization of PCL causes reversible changes in the interlayer distance of the organoclay. Extensive experimental and literature studies on this phenomenon provided clues indicating that this effect might be a result of two‐dimensional ordering of PCL chains inside the galleries of the silicate. Small angle X‐ray scattering and wide angle X‐ray scattering investigation of filaments oriented above melting point of PCL revealed that polymer lamellae were oriented perpendicularly to particles of unmodified silicate, while in PCL/organoclay systems they were found parallel to clay tactoids. Calorimetric and microscopic studies shown that clay particles are effective nucleating agents. In the nanocomposites, PCL crystallized 20‐fold faster than in the neat polymer. The crystallization rate in nanocomposites was also significantly higher than in microcomposite. Further research provided an insight how the presence of the filler affects crystalline fraction and spherulitic structure of the polymer matrix in the investigated systems. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2350–2367, 2007
Free‐volume and crystallinity in low molecular weight poly(ethylene oxide)
Authors: Machado José C. , Silva Glaura G. , Oliveira Fernando C. de , Lavall Rodrigo L. , Rieumont Jacques , Licinio Pedro , Windmöller Dario 
Published: July 2007

AbstractPositron annihilation lifetime spectroscopy (PALS), differential scanning calorimetry, X‐ray diffraction, and polarized light optical microscopy were used to study six low molar mass poly(ethylene oxide) samples with average molar masses ranging from 1 × 103 to 10 × 103 g mol−1. Dynamic light scattering was used to determine molar mass and polydispersity rigorously. Polymer samples with 70–95% crystallinity, which is an unusual range in PALS studies, were prepared by molten material quenching. The ortho‐positronium pick‐off lifetime (τ3) and relative fractional free volume (fv), determined by the free volume model, correlated well with the average molar mass and crystallinity of the polymers. X‐ray diffraction and polarized light optical data support the interpretation of positron annihilation results. PALS parameter, I3, which is associated with high cavity content, remained approximately constant at 20–22% for all samples. The cavities are present as crystallite defects in the spherulitic open texture and the amorphous phase for the low crystallinity sample (e.g., for Mw = 1390) and at the interfaces and in interlamellar spherulite regions of the more crystalline materials. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2400–2409, 2007
Shear‐enhanced crystallization of a thermoplastic polyimide derived from 3,3′,4,4′‐oxydiphthalic dianhydride and 4,4′‐oxydianiline
Authors: Zhao Guiyan , Zhang Min , Men Yongfeng , Ding Mengxian , Jiang Wei 
Published: July 2007

AbstractThe aim of this work is to investigate the effect of consecutive shear on the crystallization of an amorphous aromatic polyimide (PI) derived from 3,3′,4,4′‐oxydiphthalic dianhydride (3,3′,4,4′‐ODPA) and 4,4′‐oxydianiline (ODA). At 260 °C, the increase of shear rate or shear time leads to the increase of crystallinity. Indeed, increasing shear rate can also accelerate the crystallization behavior. Moreover, it was found that a new melting peak appeared at higher temperature for long time or high rate sheared sample. The enhancement of crystallization behavior appears directly linked to the increase of crystal thickness. Particularly, the effect of shear temperature was investigated, and the results revealed that the crystallization of the PI was more sensitive to shear at 260 °C, which was 10° above the glass transition temperature (250 °C) of the PI. Possible mechanism was proposed to illustrate the effect of consecutive shear on the crystallization of the PI polymer. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2344–2349, 2007
Flonicamid, a novel insecticide with a rapid inhibitory effect on aphid feeding
Authors: Morita Masayuki , Ueda Tsuyoshi , Yoneda Tetsuo , Koyanagi Tohru , Haga Takahiro 
Published: July 2007

AbstractFlonicamid (IKI220; N‐cyanomethyl‐4‐trifluoromethylnicotinamide), a pyridinecarboxamide compound, is a novel systemic insecticide with selective activity against hemipterous pests, such as aphids and whiteflies, and thysanopterous pests. The purpose of this study is to clarify the biological properties of flonicamid against aphids. Flonicamid is very active against aphids, regardless of differences in species, stages and morphs. This compound inhibited the feeding behaviour of aphids within 0.5 h of treatment without noticeable poisoning symptoms such as convulsion, and this antifeeding activity was not recoverable until death. The nymphs born from adults exposed to flonicamid for 3 h showed high mortality. The effect of flonicamid on the feeding activity of an individual aphid was studied using electronic monitoring of insect feeding behaviour (EMIF). Although the treated aphid attached the head of its proboscis to the leaf surface, salivation and sap feeding were strongly inhibited. These results suggest that the main insecticidal mechanism of flonicamid is starvation based on the inhibition of stylet penetration to plant tissues. Copyright © 2007 Society of Chemical Industry