bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of new metabolites from in vivo biotransformation of 2‐amino‐ 3‐methylimidazo[4,5‐f]quinoline in mouse by mass spectrometry
Authors: Hsu Fong‐Fu , Lakshmi Vijaya M. , Zenser Terry V. 
Published: July 2009

AbstractIn studying the metabolic pathways underlying the mechanism of carcinogenesis of the heterocyclic amine of 2‐amino‐3‐methylimidazo[4,5‐f]quinoline (IQ), we recently found a new metabolite which gave an [M + H]+ ion of m/z 217 when subjected to electrospray ionization (ESI) in positive‐ion mode. Following ip injection of this metabolite of m/z 217 (designated as m/z 217) to beta‐naphthoflavone‐treated mice, 57% of the total radioactivity was recovered in a 24‐h mouse urine sample. HPLC separation followed by MS analysis indicates that the urine sample contained m/z 217 (36 ± 3% of total recovered radioactivity) and two other peaks that gave rise to the [M + H]+ ions of m/z 393 (31 ± 4%, designated as m/z 393) and m/z 233 (14 ± 1%, designated as m/z 233). Beta‐glucuronidase treatment of m/z 393 resulted in a radioactive peak corresponding to m/z 217. ESI in combination with various mass spectrometry techniques, including multiple‐stage mass spectrometry, exact mass measurements and H/D exchange followed by tandem mass spectrometry, was used for structural characterization. The urinary metabolites of m/z 217, 393 and 233 were identified as 1,2‐dihydro‐2‐amino‐5‐hydroxy‐3‐methylimidazo[4,5‐f]quinoline, 1,2‐dihydro‐2‐amino‐5‐O‐glucuronide‐3‐methylimidazo[4,5‐f]quinoline and 1,2‐dihydro‐2‐amino‐5,7‐dihydroxy‐3‐methylimidazo[4,5‐f]quinoline, respectively. Our results demonstrated that m/z 217 is biotransformed in vivo to m/z 393 by O‐glucuronidation and to m/z 233 by oxidation. The observation of these more polar metabolites relative to IQ suggests that they may arise from a previously undescribed detoxicification pathway. Copyright © 2009 John Wiley & Sons, Ltd.
Interdecadal variation of tropical cyclone making landfall over the Korean Peninsula
Authors: Choi Ki‐Seon , Kim Baek‐Jo , Kim Do‐Woo , Byun Hi‐Ryong 
Published: July 2009

AbstractThe results from applying indices for the accumulated cyclone energy and the total movement to the change‐point analysis showed that depending on the frequency of the tropical cyclone (TC) over the Korean Peninsula for the past 54 years, the results could be categorised into three different categories: High‐frequency period‐1 (1951–1965), low‐frequency period (1966–1985), and high‐frequency period‐2 (1986–2004). During the second high‐frequency period, there were three distinct recorded changes. First, compared to the other two periods, majority of the TC occurred in the southeastern regions. Second, the TC track and recurving location shifted to the east. Therefore, the total number of TCs passing mainland China had reduced whereas the number of TCs moving across the eastern shores of mainland China showed a relative increase. In addition, the key landing area on the Korean Peninsula shifted from the western coastlines to the southern coastlines. Third, the TC intensity increased, which could be attributed to the fact that the new TCs migrated over the sea rather than moving over mainland China. Finally, these series of changes resulted in the intensification of the monsoon trough in the eastern region compared to the other two periods, as well as the synoptic characteristics preventing the westward expansion of the western North Pacific high (WNPH). Copyright © 2009 Royal Meteorological Society
Age‐ and sex‐related changes of humeral head microarchitecture: Histomorphometric analysis of 60 human specimens
Authors: Barvencik Florian , Gebauer Matthias , Beil Frank Timo , Vettorazzi Eik , Mumme Marcus , Rupprecht Martin , Pogoda Pia , Wegscheider Karl , Rueger Johannes M. , Pueschel Klaus , Amling Michael 
Published: July 2009

AbstractFractures of the humeral head are frequent and will further increase due to demographic changes. Prior to operative fracture treatment, the regional differences of bone quality, especially of elderly people, have to be carefully considered to assure stable implant fixation. However, conclusive data concerning the variation of histomorphometric parameters are still lacking. Consequently, the purpose of this study was to analyze the age‐ and sex‐related changes in bone microarchitecture. For that reason, 60 proximal humeri were harvested from patients at autopsy. Twelve regions of interest (ROI) were defined for each centered coronar humeral head slice and the specimens were subjected to radiographic, histological, and histomorphometric analyses. We could demonstrate that in contrast to men, women over 60 years of age had a significant age‐related decrease in bone mass. The most prominent decrease was observed in the region of the greater tuberosity, which represents an osteoporotic fracture site. The most superior and medially located part of the centered coronar humeral head slice showed, independent from age and sex, the highest bone mass and can therefore be considered as the best location for subchondral screw placement. Taken together, our study revealed distinct sex‐related changes of the humeral head bone microarchitecture with aging, which should be considered in implant positioning. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:18–26, 2010
LC‐MS/MS method for the determination of melamine in rat plasma: Toxicokinetic study in Sprague–Dawley rats
Authors: Yang Feng , Mao Yu , Zhang Xiaodong , Ma Zhiqiang , Zhang Xinrong 
Published: July 2009

AbstractMost recently, melamine has raised international concern for its catastrophic health effects stemming from tainted infant formula. So far there is limited information concerning the pharmacokinetics of melamine in mammals. The present report concerns the development and validation of a sensitive HPLC‐ESI‐MS/MS method for the pharmacokinetic study of melamine in rat. The method employed a simple liquid–liquid extraction process for plasma sample cleanup, and the extraction recoveries of melamine from plasma were consistent at different concentrations. There was a linear relationship between chromatographic area and concentration over the range of 10–5000 ng/mL for melamine in plasma (R = 0.995). In this work, for the first time, melamine was administered intravenously and orally to Sprague–Dawley rats and the pharmacokinetic characteristics of this contaminant were investigated. The mean values of major pharmacokinetic parameters of oral availability, the mean steady‐state distribution volume (Vss), clearance, and plasma elimination half‐life (T1/2) of melamine in Sprague–Dawley rats were 72.9 ± 13.2%, 102.5 ± 12.5 mL/kg, 20.1 ± 3.8 mL/h/kg, and 4.9 ± 0.5 h, respectively. The rats pharmacokinetic study results suggested that melamine was predominantly restricted to blood or extracellular fluid and is not extensively distributed to most organ tissues. Meanwhile, melamine should be primarily eliminated by renal filtration for rats and does not undergo significant metabolism. These data should be useful to regulatory for risk assessment.
Static and dynamic superheated water extraction of essential oil components from Thymus vulgaris L.
Authors: Dawidowicz Andrzej L. , Rado Ewelina , Wianowska Dorota 
Published: July 2009

AbstractSuperheated water extraction (SWE) performed in both static and dynamic condition (S‐SWE and D‐SWE, respectively) was applied for the extraction of essential oil from Thymus vulgaris L. The influence of extraction pressure, temperature, time, and flow rate on the total yield of essential oil and the influence of extraction temperature on the extraction of some chosen components are discussed in the paper. The SWE extracts are related to PLE extracts with n‐hexane and essential oil obtained by steam distillation. The superheated water extraction in dynamic condition seems to be a feasible option for the extraction of essential oil components from T. vulgaris L.
Evaluation of silica monoliths in affinity microcolumns for high‐throughput analysis of drug–protein interactions
Authors: Yoo Michelle J. , Hage David S. 
Published: July 2009

AbstractSilica monoliths in affinity microcolumns were tested for the high‐throughput analysis of drug–protein interactions. HSA was used as a model protein for this work, while carbamazepine and R‐warfarin were used as model analytes. A comparison of HSA silica monoliths of various lengths indicated columns as short as 1 to 3 mm could be used to provide reproducible estimates of retention factors or plate heights. Benefits of using smaller columns for this work included the lower retention times and lower back pressures that could be obtained versus traditional HPLC affinity columns, as well as the smaller amount of protein that is required for column preparation. One disadvantage of decreasing column length was the lower precision that resulted in retention factor and plate height measurements. A comparison was also made between microcolumns containing silica particles versus silica monoliths. It was demonstrated with R‐warfarin that supports could be used in HSA microcolumns for the determination of retention factors or plate heights. However, the higher efficiency of the silica monolith made this the preferred support for work at higher flow rates or when a larger number of plates are needed during the rapid analysis of drug–protein interactions.
New Thermosets Obtained by Thermal and UV‐Induced Cationic Copolymerization of DGEBA with 4‐Phenyl‐γ‐butyrolactone
Authors: Fernández‐Francos Xavier , Salla Josep M. , Pérez Guillermo , Mantecón Ana , Serra Àngels , Ramis Xavier 
Published: July 2009

AbstractMixtures of DGEBA with 4‐phenyl‐γ‐butyrolactone (PhBL) were cationically copolymerized in the presence of ytterbium triflate or triarylsulfonium hexafluoroantimoniate as thermal or photo initiator respectively. Changes during curing and final properties of the cured materials were studied by means of DSC, FT‐IR/ATR, TMA, DMTA, TGA and densitometric measurements. The formation of a network containing polyether and poly(ether‐ester) moieties was demonstrated to take place through the ring‐opening polymerization of a spiroorthoester intermediate (SOE) formed during the copolymerization. An increase in the proportion of lactone resulted in an increase in the curing rate, a decrease in the shrinkage after gelation and in the thermal stability and glass transition temperature (Tg). A strong influence of the initiator on the curing mechanism was observed. As a consequence, the photocured materials exhibited superior thermal stability and Tg than those obtained thermally.magnified image
The Influence of Reaction Conditions on the Copolymer Composition in Inverse Miniemulsion
Authors: Wiechers Susann , Schmidt‐Naake Gudrun 
Published: July 2009

AbstractSummary: Water‐soluble poly(2‐acrylamido‐2‐methylpropane‐1‐sulfonic acid‐co‐1‐vinylimidazole) (P(AMPS‐co‐1‐VIm)) and poly(2‐acrylamido‐2‐methylpropane‐1‐sulfonic acid‐co‐2‐(dimethylamino)ethyl methacrylate (P(AMPS‐co‐DAMA)) are studied as it is known that the copolymer composition is affected by pH of the monomer phase in inverse miniemulsion. The distribution of the basic monomers in the continuous and dispersed phase changes due to their degrees of protonation. The amounts of the monomers in the cyclohexane phase is determined by gas chromatography, the copolymer composition is studied by elemental and thermogravimetric analysis. An insight into the monomer distribution in the polymer is provided by simultaneous potentiometric and conductometric titration of polymer solutions.
New Biocompatible Microgels
Authors: Imaz Ainara , Forcada Jacqueline 
Published: July 2009

AbstractSummary: Microgel particles have received an increasing interest in the biomedical field. Temperature‐sensitive microgels gained particular interest due to their potential use as controlled drug delivery systems. With the objective to produce new thermoresponsive biocompatible microgels, the synthesis and characterization of two families of microgel particles obtained by using N‐vinylcaprolactam (VCL) as main monomer and N,N′‐methylenbisacrylamide (BA) or poly(ethylene glycol) diacrylate (PEGDA) as crosslinkers are described. Evidence of hydrolysis VCL during polymerization is also presented.
Oxygen Diffusion into Polymer‐Clay Composite Films as a Function of Clay Content and Temperature
Authors: Uğur Şaziye , Yargi Önder , Elaissari Abdelhamid , Pekcan Önder 
Published: July 2009

AbstractSummary: A simple fluorescence technique is proposed for the measurement of the diffusion coefficient of oxygen into polystyrene‐clay composite films as a function of clay content and temperature. The composite films were prepared from a mixture of surfactant‐free pyrene‐labeled polystyrene latexes and modified Na‐montmorillonite clay of various compositions at room temperature. Diffusion measurements were performed with films at room temperature for seven different clay contents (0, 5, 10, 20, 30, 50 and 60 wt.%). The diffusion coefficients of oxygen increased from 7.4 × 10−10 to 26.9 × 10−10 cm2s−1 with increasing clay content. On the other hand, diffusion measurements were performed over a temperature range of 25–70 °C for 0, 5 and 20 wt.% clay content films. The calculated diffusion activation energies decreased from 2.44 to 0.44 kcal/mol with increasing clay content. No clay content and temperature effects were observed on quenching rate constant and mutual diffusion coefficient values. The results showed that the diffusion coefficients are strongly dependent on both the temperature and clay content in the film.
Investigation of Water‐Based Emulsions: Surface and Film‐Forming Properties
Authors: Tigci Yelda , Sarac Ayfer 
Published: July 2009

AbstractSummary: In the present study, reaction components such as emulsifiers, emulsifier combinations, and initiators were used for the particle stabilization of water‐borne vinyl acetate ‐ butyl acrylate copolymer latexes. The effects of these parameters on the colloidal film‐forming properties of the vinyl acetate‐co‐butyl acrylate latex colloidal, physicochemical, surface, and film forming properties were investigated, in particular the aspect of their surface coating applications.
GLUT1 gene mutations cause sporadic paroxysmal exercise‐induced dyskinesias
Authors: Schneider Susanne A. , Paisan‐Ruiz Coro , Garcia‐Gorostiaga Ines , Quinn Niall P. , Weber Yvonne G. , Lerche Holger , Hardy John , Bhatia Kailash P. 
Published: July 2009

AbstractParoxysmal exercise‐induced dyskinesias (PED) are involuntary intermittent movements triggered by prolonged physical exertion. Autosomal dominant inheritance may occur. Recently, mutations in the glucose transporter 1 (GLUT1) gene (chr. 1p35–p31.3) have been identified as a cause in some patients with autosomal dominant PED. Mutations in this gene have previously been associated with the GLUT1 deficiency syndrome. We performed mutational analysis in 10 patients with apparently sporadic PED. We identified two novel GLUT1 mutations, at least one likely to be de‐novo, in two of our patients. Onset was in early childhood. One of our patients had a predating history of childhood absence epilepsy and a current history of hemiplegic migraine as well as a family history of migraine. The other patient had no other symptoms apart from PED. Brain MRI showed cerebellar atrophy in one case. Mutations in GLUT1 are one cause of apparently sporadic PED. The detection of this has important implications for treatment as ketogenic diet has been reported to be beneficial. © 2009 Movement Disorder Society
A novel LTCC multilayer SIW linear phase filter
Authors: Shen Wei , Yin Wen‐Yan , Sun Xiao‐Wei , Wei Qi‐Fu 
Published: July 2009

AbstractIn this article, a novel multilayer substrate‐integrated waveguide (SIW) linear phase filter is proposed. Four SIW cavities are placed in two layers based on a standard low temperature cofired ceramic technology. Neural network is used to improve the efficiency of design. One slot which is etched on the top metal layer of SIW cavity is adopted to suppress the first high mode. Flat group delay characteristics can be achieved in the filter that has a rejection level of −25 dB in upper stopband. The filter has a 55% area reduction in comparison with planar structure. Good agreement is acquired between measured and simulated results. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2357–2360, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24595
Dual‐band‐rejection filter based on split ring resonator (SRR) and complimentary SRR
Authors: Hu Xin , Zhang Qiaoli , He Sailing 
Published: July 2009

AbstractA novel concept of a compact, low insertion‐loss dual‐band‐rejection filter (DBRF) is proposed, and its equivalent circuit model is given. The filter consists of single split ring resonators (SRRs) on the top of the host microstrip line and Complimentary SRR etched on the back ground plane. The dimensions of the structure are as small as 1.4 cm × 2 cm, while high frequency selectivity is achieved at both band edges due to the presence of two transmission zeros. The filter has an insertion loss of better than 1 dB, a return loss of larger than 10 dB in the passband from 3.3 to 4.0 GHz, and two rejections of greater than 30 dB within 2.5–2.6 and 5.2–5.6 GHz. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2519–2522, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24596
Size efficient low‐noise amplifier for 2.4 GHz ISM‐band transceiver
Authors: Jhon Hee‐Sauk , Jung Hakchul , Jeon Jongwook , Koo MinSuk , Park Byung‐Gook , Lee Jong Duk , Shin Hyungcheol 
Published: July 2009

AbstractThis letter presents the implementation technique to reduce circuit area in designing 2.4 GHz CMOS low‐noise amplifier (LNA) using size efficient inductors. We applied a vertically shunt (M6/M5) and a 3‐D helical inductor to input and output matching network to obtain low noise figure and to save silicon area, simultaneously. Because these inductors have smaller area occupation, overall Si area was reduced. Moreover, the feedback capacitor, Cf is used to compensate the gain degradation from the high resistive 3‐D helical inductor at the LNA output stage. The proposed LNA has a gain of 12.5 dB, noise figure (NF) of 2.72 dB, and −5 dBm IIP3, whereas dissipating 5.3 mA from 1.5 V supply. Without any degradation in terms of circuit performance, the size of proposed LNA is reduced by 49.5% compared with that using the conventional asymmetric inductors. For low cost, the LNA has been fabricated using a 0.18 μm mixed‐signal CMOS process with top metal thickness of 0.84 μm. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2304–2308, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24600
Multiwavelength ytterbium‐doped fiber ring laser
Authors: Moghaddam M. R. A. , Harun S. W. , Paul M. C. , Pal M. , Dhar A. , Sen R. , Das S. , Bhadra S. K. , Ahmad H. 
Published: July 2009

AbstractA multiwavelength Ytterbium‐doped fiber ring laser operating at 1030 nm region is demonstrated using a Sagnac loop mirror. The Ytterbium‐doped fiber used is drawn from Yb2O3‐doped perform, which is fabricated through deposition process in conjunction with a solution doping technique. The loop mirror is constructed using a 3dB coupler and a piece of polarization maintaining fiber (PMF). The fiber laser generates a multiwavelength oscillation with up to five lines by adjusting both polarization controllers in the ring cavity. The line spacing is obtained at 2.1 nm, which is strongly dependent on the PMF's length used. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2511–2512, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24605
Novel microstrip low‐pass filters with fractal defected ground structures
Authors: Kurgan P. , Kitlinski M. 
Published: July 2009

AbstractIn this study, three microstrip low‐pass filters (LPFs) containing fractal‐shaped defected ground structures have been designed and manufactured. To improve the performance of microstrip LPF, cascades of inductively coupled fractal resonators have been applied. Simultaneously, to achieve relatively constant microstrip impedance resulting in essentially low reflection losses, a modification of the strip geometry has been introduced. The measured results excellently prove the validity and efficiency of the proposed new solutions. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2473–2477, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24607
Folded planar inverted‐F antenna (PIFA) with two via holes for bandwidth enhancement
Authors: Oh Il‐Young , Wi Sang‐Hyuk , Lee Yongshik , Yook Jong‐Gwan 
Published: July 2009

AbstractIn this article, new type of planar inverted F antenna (PIFA) is presented. The radiating element of the antenna is folded to the backside of the substrate. Moreover, a substantial improvement in the bandwidth can be achieved by optimizing the locations of the two via holes that connect the radiating elements on top and bottom side of the substrate. Measured results show that more than 6.7% increase in the relative bandwidth around 2.6 GHz compare to the uniplanar topology, while maintaining nearly the same radiation patterns. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2413–2416, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24610
A low cost miniaturized circularly polarized antenna for UHF radio frequency identification reader applications
Authors: Wang Zhongbao , Fang Shaojun , Fu Shiqiang 
Published: July 2009

AbstractA low cost miniaturized CP antenna is proposed for UHF RFID (Radio Frequency Identification) reader applications. The antenna is composed of a vertical ground and a square‐ring patch with truncated corners. A novel capacitively coupled feed structure is proposed for good impedance matching. The antenna hasS11< −20 dB and a gain level of about 6.9 dBi at 920–925 MHz (Chinese RFID band). Comparing to the conventional CP antenna, the size of the proposed antenna can be reduced by 33%. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2382–2384, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24612
Triple‐band cavity‐backed Z‐like slot antenna for WLAN applications
Authors: Zhang Qiu‐Yi , Chu Qing‐Xin 
Published: July 2009

AbstractIn this letter, a triple‐band Z‐like cavity‐backed slot antenna was designed, fabricated, and measured. A Z‐like slot is employed here to attain the triple‐band operation, whereas a metallic superstrate is placed above the Z‐like slot to achieve the high‐gain enhancement within the lower bandwidth at 2.45 GHz. The parametric studies of the proposed‐antenna are provided and mechanisms of triple‐band operation and gain enhancement within the lower bandwidth are also discussed. The measured‐results are in good agreements with simulated ones, which reach the bandwidth from 2.26 to 2.58 GHz, 5.15 to 5.28 GHz, and 5.68 to 5.88 GHz, respectively. Simulated‐ and measured‐gain results show that the proposed‐antenna reaches 11.59 dBi at 2.45 GHz, higher than 7 dBi at band of 5.25 GHz and 6.0 dBi at band of 5.85 GHz, respectively. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2296–2301, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24616