bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cloning, sequencing and expression of full‐length Campylobacter invasion antigen B gene operon from Campylobacter lari
Authors: Onozato Junnosuke , Kumagai Atsuko , Sekizuka Tsuyoshi , Tazumi Akihiro , Moore John E. , Millar B. Cherie , Matsuda Motoo 
Published: March 2009

AbstractA novel PCR primer pair for amplification of full‐length cia B gene from thermophilic campylobacters, generated an amplicon of approximately 2.2 kilo base pairs (kbp) with all 18 isolates (n = 7 for urease‐negative (UN) C. lari; n = 9 urease‐positive thermophilic Campylobacter (UPTC); n = 1 C. jejuni; n = 1 C. coli). The putative open reading frame (ORF) of the cia B from C. lari isolates consisted of 1,833 bp similarly, but differing from those of C. jejuni and C. coli isolates. The putative promoter structures consisting of a semi‐conserved T ‐rich sequence and a consensus sequence at the –10 region were identified upstream of the putative ORF in all the C. lari isolates. A start codon ATG and a probable ribosome binding site were also identified in all the isolates. In addition, two distinctly different and taxon (UN C. lari and UPTC) dependent hypothetically intrinsic ρ ‐independent transcriptional terminators for the cia B were identified to occur within the C. lari. Reverse transcription–PCR analysis identified the transcription of cia B gene in the C. lari cells. The neighbor joining tree suggested that the nucleotide sequence information of the cia B had molecular discrimination efficacy among UN C. lari, UPTC, C. jejuni and C. coli organisms. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Destruxin production of Metarhizium anisopliae under carbon and nitrogen exhaustion
Authors: Wang Hui , Hutwimmer Stefan , Strasser Hermann , Burgstaller Wolfgang 
Published: March 2009

AbstractDestruxins (dtx) A, B, and E, showing a variety of biological activities, are the main toxic secondary metabolites of the entomopathogenous ascomycete Metarhizium anisopliae Bipesco 5, a widely used biocontrol production strain. Dynamics of dtx biosynthesis were monitored during liquid fermentation in a chemically defined medium. During shake flask cultivation with excess carbon, nitrogen and phosphate, approximately 50, 20, and 100 mg l–1 dtx A, B, and E were produced after 12 d. Destruxins were produced during exponential growth phase and in the stationary phase. Carbon exhaustion in the culture broth was demonstrated to affect destruxin production to a minor degree: Absolute dtx amounts in the liquid increased also after glucose exhaustion; dtx amounts referred to biomass increased further evidently in shake flasks or slightly in bioreactor experiments after carbon limitation occurred. Contrarily, nitrogen exhaustion resulted in an evident decline in dtx amounts referred to biomass. Absolute amounts in the culture broth, however, still increased slightly the following four days in bioreactor experiments. From this we conclude that dtx production is highly influenced by nitrogen availability. Generally, dtx production in bioreactors with controlled aeration (1 vvm) was significantly lower than in shake flasks. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A novel way to enhance the oil recovery ratio by Streptococcus sp. BT‐003
Authors: Xu Tao , Chen Chang , Liu Chunqiao , Zhang Shurong , Wu Ying , Zhang Peng 
Published: March 2009

AbstractDegrading hydrocarbon by Streptococcus sp. BT‐003 as a kind of microbe for oil recovery was analyzed in this paper. The Streptococcus sp. BT‐003 showed that it could use crude oil as the sole source of carbon and produce organic acid, bio‐gas and polysaccharide which were propitious to emulsify and reduce the viscosity of crude oil. After cultivating 8–14 h, the viscosity of crude oil reduced from 8000–15000 mPa · s to 50–250 mPa · s. The content of organic acid increased 8–15 times, and carbon dioxide and polysaccharide reached 55 ml/l and 8 g/l respectively. Paraffin and resin reduced by 60–95%, and light components increased obviously. Fluid rheology was better than before, the interfacial tension between the crude oil and water were reduced effectively. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Genetic characterization of vancomycin‐resistant enterococci isolates from wild rabbits
Authors: Figueiredo Nicholas , Radhouani Hajer , Gonçalves Alexandre , Rodrigues Jorge , Carvalho Carlos , Igrejas Gilberto , Poeta Patrícia 
Published: March 2009

AbstractThe presence of van A‐containing E. faecium isolates was demonstrated in three of 77 faecal samples (3.9%) of wild rabbits recovered in Portugal. Enterococcal strains with intrinsic vancomycin resistance (van C‐1 or van C‐2/3 gene) were found in five (6.5%) and three (3.9%) faecal samples, respectively. The mechanisms of resistance for other antibiotics were studied in these vancomycin‐resistant isolates. All van A strains showed resistance for tetracycline [with the presence of tet (L) gene, associated or not with tet (M) gene] and for erythromycin [with the presence of the erm (B) gene]. Two isolates were resistant to ciprofloxacin and one to ampicillin. Two van C‐1 strains and one van C‐2/3 strain were tetracycline resistant [containing the tet (M) gene associated with tet (L) gene] and erythromycin resistant [with erm (B) gene]. Two van C‐1 and two van C‐2/3 strains were also ciprofloxacin resistant and one van C‐1 strain was, additionally, resistant to quinupristin‐dalfopristin. The two remaining isolates (van C‐1, van C‐2/3) did not show resistance for any additional antibiotic. The intestinal tract of wild rabbits could be a reservoir of van A‐containing enterococci. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Blood flow analysis of compressed nerve root after intravenous injection of lipo‐prostaglandin E1
Authors: Kobayashi Shigeru , Baba Hisatoshi , Takeno Kenichi , Shimada Seiichro , Kubota Masafumi , Yayama Takafumi , Miyazaki Tsuyoshi , Uchida Kenzo , Suzuki Yoshihiko 
Published: March 2009

AbstractProstaglandin E1 (PGE1) is a potent vasodilator as well as an inhibitor of platelet aggregation and has therefore attracted interest as a therapeutic drug for lumbar canal stenosis. However, investigations in the clinical setting have shown that PGE1 is effective in some patients but not in others, although the reason for this is unclear. The aim of the present study was to measure changes in intraradicular blood flow after intravenous injection of lipo‐PGE1 (0.15 µg/kg) using a laser Doppler flow meter in control model and nerve root compression model. Then, the nerve root in which blood flow was measured was removed and examined histologically. Intravenous injection of lipo‐PGE1 also resulted in marked increase of blood flow in the uncompressed nerve roots of the control group, but caused minimal enhancement of blood flow at the sites of nerve root compression exhibiting Wallerian degeneration. It is concluded that lipo‐PGE1 has less effect on markedly degenerated nerve roots than it does on those that are normal. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Coronatine‐induced lateral‐root formation in cotton (Gossypium hirsutum) seedlings under potassium‐sufficient and ‐deficient conditions in relation to auxin
Authors: Zhang Zhiyong , Yang Fuqiang , Li Bo , Egrinya Eneji A. , Li Jianmin , Duan Liusheng , Wang Baomin , Li Zhaohu , Tian Xiaoli 
Published: March 2009

AbstractA large root system plays a decisive role in potassium (K)‐acquisition efficiency of cotton. Coronatine (COR), a non‐host‐specific phytotoxin, may affect the auxin level in plants and might therefore be useful in regulating lateral‐root (LR) development. Our objectives were (1) to examine the effects of COR on root development, especially the LR formation in hydroponically grown cotton seedlings, and (2) to explore possible mechanisms involved. The results showed that K deficiency (0.05 mM) significantly reduced LR formation in cotton seedlings, possibly due to the decrease of endogenous indole acetic acid (IAA) in roots by more than half. Following the application of 10 nM COR, the LRs significantly increased by 26% in K‐sufficient (0.5 mM) solution and by 95% in K‐deficient solution. Although COR did not increase the free IAA level in the primary root, the polar auxin‐transport inhibitor N‐1‐naphthylphthalamic acid (NPA) decreased its stimulating effects on LR formation by 25%–30%, suggesting that the COR‐induced LR formation was independent of increased auxin level but likely associated with auxin transport. Treatment of plants with 1‐naphthalene acetic acid (NAA) increased LR formation at NAA concentrations of 100 nM, but had no effect at 10 nM. In the presence of 1 nM COR, however, NAA increased LR formation at 10 nM concentrations. This indicates that LR formation due to COR possibly involves changes in auxin sensitivity. In addition, the shorter LRs of COR‐treated seedlings were clearly restored when COR was removed from solutions for 12 d, and the total root length, total root surface area as well as K uptake increased significantly, suggesting that COR may be potentially useful for enhancing the K‐acquisition efficiency of cotton seedlings.
Effect of phosphite–phosphate interaction on growth and quality of hydroponic lettuce (Lactuca sativa)
Authors: Thi Bich Thao Hoang , Yamakawa Takeo , Shibata Katsuhiro 
Published: March 2009

AbstractAlthough the fungicidal properties of phosphite have been recognized, its potential as a fertilizer is still being debated. The information on how phosphite affects the growth and quality of plants in relation to phosphate (Pi) also remains unknown. This study was conducted to investigate the effect of phosphite in relation to Pi on growth and quality parameters of lettuce (Lactuca sativa L.). The results showed that addition of phosphite to the nutrient solution at different rates ranging from 0.05 to 2 mM significantly increased total P, water‐extractable Pi, and phosphite in both shoots and roots, but did not improve plant growth under various Pi supplies (0.05, 0.1, 0.15, and 0.3 mM as Pi levels for approximately 50%, 80%, 90%, and 100% of the maximum plant growth, respectively), indicating that phosphite was well absorbed by roots and mobile inside the plants, but did not provide any P nutrition. Also, no stimulating effect of any Pi–phosphite combination was observed. The effect of phosphite on plant growth was strongly dependent on the level of Pi supply. In general, application of phosphite up to 2 mM did not influence the growth of Pi‐sufficient plants. However, plants fertilized with Pi for about 90% of maximum growth were still vulnerable to phosphite at 2 mM. The negative effect of phosphite was found even at concentrations as low as 0.2 mM, when plants were supplied with Pi adequate for about 80% of maximum growth or less. At 0.05 mM, phosphite had marginal effects on plant growth under all the Pi levels. Although phosphite itself had little influence on the ascorbate and mineral concentrations of lettuce, its application to Pi‐deficient plants may decrease the mineral concentrations of plants brought about by the inhibitory effect of phosphite on root growth and hence nutrient uptake. Since phosphite is an effective fungicide for lettuce, care should be taken on Pi supplies prior to application of phosphite products to minimize the harmful effects.
Effects of head group of cationic surfactants on the hydrolysis of p‐nitrophenyl acetate catalyzed by α‐chymotrypsin
Authors: Ghosh Kallol K. , Verma Santosh Kumar 
Published: March 2009

AbstractThe kinetics of hydrolysis of p‐nitrophenyl acetate catalyzed by α‐chymotrypsin (α‐CT) has been studied in the presence of several cationic surfactants having different head groups maintaining the dodecyl hydrophobic residue and bromide counterion. The enzyme activity was tested in the presence of dodecyl trimethylammonium bromide (DTAB), dodecylpyridinium bromide (DPB), dodecyldimethylethanolammonium bromide (DDMEAB), dodecyldiethylethanolammonium bromide (DDEEAB), benzyldimethyldodecylammonium bromide (BDDAB), and dodecyltriphenylphosphonium bromide (DTPB) surfactants. The extent of superactivity depends upon head groups of surfactants. The activity of α‐CT depends on the surfactant concentration and it varies with the surfactant head group dimensions (DTPB > DDEEAB > DTAB > BDDAB > DDMEAB > DPB). For all surfactants, DTPB exhibits highest superactivity. The effects of surfactants on the apparent kinetic parameters like Michaelis constant Km and the catalytic constant kcat have been determined. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 377–381, 2009
Solvent interactions in the allylation of piperidine
Authors: Devender T. , Manikyamba P. 
Published: March 2009

AbstractThe reaction between allylbromide and piperidine has been studied in different protic and aprotic solvents. The reaction is first order with respect to [allylbromide] and [piperidine]. A correlation analysis of the rate data with solvent properties shows that polarity (Y), polarizability (P), and electrophilicity (E) of the solvent simultaneously influence the rate of reaction. From the regression analysis, information regarding the relative solvation of the reactants and the activated complex is obtained and a solvation model is proposed. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 421–425, 2009
The oxyfunctionalization of 4‐methylcoumarins using dimethyldioxirane
Authors: Ćavar Sanja , Kovač Franci 
Published: March 2009

AbstractThe kinetic study of the efficient regioselective oxidation of the CC double bond of 4‐methylcoumarins with isolated dimethyldioxirane was investigated using UV–vis spectroscopy methods. In the excess of dimethyldioxirane, the pyrone ring of a coumarin skeleton is selectively epoxidated and hydroxylated in neutral media, in high yields. Kinetic analyses demonstrate two independent reaction pathways, epoxidation and hydroxylation, respectively, which was also confirmed using kinetic isotope effect methods. Both reaction products were isolated, and their structures were determined by NMR and mass spectra. The position of methyl groups attached at the aromatic part of coumarin molecule shows significant influence on kinetic rate constants and activation parameters. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 414–420, 2009
Hochfester und leicht umformbarer Stahl für den Automobilbau
Authors: Ganzer Stefan , Albert Florian , Schmidt Michael 
Published: March 2009

AbstractGerade im Automobilbau stellt der Stoff‐, Fertigungs‐ und Konzeptleichtbau, nicht nur im Hinblick auf die CO2‐Debatte, ein wichtiges Thema dar. Gesucht werden unter anderem Materialien, die eine hohe Festigkeit erreichen, sich aber dennoch leicht umformen lassen. Eine Möglichkeit stellt der warmumformbare höchstfeste Mangan‐Bor‐Stahl 22MnB5 (1.5528) dar. Dieser Artikel präsentiert Ergebnisse zum Laserstrahlschweißen von Usibor 1500P und BTR 165 jeweils vor und nach der Warmumformung.
Computer Simulations of Interpolyelectrolyte Complexes Formed by Star‐like Polymers and Linear Polyelectrolytes
Authors: Larin Sergey , Lyulin Sergey , Lyulin Alexey , Darinskii Anatoly 
Published: March 2009

AbstractComplexes formed by star‐like polymers of various topology and oppositely charged linear polyelectrolytes were simulated using Brownian dynamics technique. Structural properties and their dependence on the polyelectrotyte charge were investigated and compared with similar data for complexes with dendrimers. Remarkable overcharging was observed for all stars in complexes.
Sensitivity of feedback‐enhanced MRI contrast to macroscopic and microscopic field variations
Authors: Huang Susie Y. , Yang Sophia S. , Lin Yung‐Ya 
Published: March 2009

AbstractNonlinear feedback interactions have been shown to amplify contrast due to small differences in resonance frequency arising from microscopic susceptibility variations. Determining whether the selectivity of feedback‐based contrast enhancement for small resonance frequency variations remains valid even in the presence of macroscopic field inhomogeneity is important for transitioning this new methodology into in vivo applications in imaging systems with lower field strengths and poorer homogeneity. This work shows that contrast enhancement under the radiation damping (RD) feedback field is sensitive to microscopic intravoxel frequency variations. Feedback‐enhanced contrast provides superior signal differentiation from voxels with distinct microscopic frequency distributions compared with T‐weighted imaging, while remaining robust to macroscopic field gradients, which frequently give rise to artifacts by other frequency‐sensitive methods. Applying multiple RF pulses during evolution under RD and actively adjusting the phase and amplitude of the feedback field are shown to further improve signal differentiation. Experimental results reveal that feedback‐enhanced contrast can generate positive contrast, reflecting microscopic field variations induced by strong local dipole fields, such as those created by blood vessels and superparamagnetic iron oxide nanoparticles. Extensions to in vivo imaging at lower field strengths are discussed in the context of amplifying the RD field via active electronic feedback. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Fast high‐resolution T1 mapping using inversion‐recovery look‐locker echo‐planar imaging at steady state: Optimization for accuracy and reliability
Authors: Shin Wanyong , Gu Hong , Yang Yihong 
Published: March 2009

AbstractA fast T1 measurement sequence using inversion recovery Look‐Locker echo‐planar imaging at steady state (IR LL‐EPI SS) is presented. Delay time for a full magnetization recovery is not required in the sequence, saving acquisition time significantly for high‐resolution T1 mapping. Imaging parameters of the IR LL‐EPI SS sequence were optimized to minimize the bias from the excitation pulses imperfection and to maximize the accuracy and reliability of T1 measurements, which are critical for its applications. Compared with the conventional inversion recovery Look‐Locker echo‐planar imaging (IR LL‐EPI) sequence, IR LL‐EPI SS method preserves similar accuracy and reliability, while saving 20% in acquisition time. Optimized IR LL‐EPI SS provided quantitative T1 mapping with 1 × 1 × 4 mm3 resolution and whole‐brain coverage (28 slices) in approximately 4 min. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Investigation of quantitative magnetisation transfer parameters of lesions and normal appearing white matter in multiple sclerosis
Authors: Cercignani M. , Basile B. , Spanò B. , Comanducci G. , Fasano F. , Caltagirone C. , Nocentini U. , Bozzali M. 
Published: March 2009

AbstractThe aim of this study was to use quantitative magnetisation transfer (MT) imaging to assess the different pathological substrates of tissue damage in multiple sclerosis (MS) and examine whether the MT parameters may be used to explain the disability in relapsing remitting (RR) MS. Thirteen patients with RRMS and 14 healthy controls were prescribed conventional MRI and quantitative MT imaging at 3.0 T. A two‐pool model of MT (where A refers to the free pool and B to the macromolecular pool) was fitted to the data yielding a longitudinal relaxation rate RA, a relative size F of macromolecular pool, transverse relaxation times T and T for the two pools and a forward exchange rate RM. The MT ratio (MTR) was also computed. The mean MT parameters of the normal appearing white matter (NAWM) and of lesions in patients, and of white matter in controls were estimated. MT parameters were significantly different between lesions and NAWM in patients, and between the NAWM and the white matter of controls (with the exception of T and the MTR). Two models were investigated using ordered logistic regression, with the expanded disability status scale (EDSS) as the dependent variable. In the first one, mean NAWM MT parameters and lesion load were entered as explanatory variables; in the second one, mean MT variables within lesions and lesion load were entered as explanatory variables. Unexpectedly, T was the parameter most significantly associated with EDSS in NAWM. This parameter might represent a weighted average of the relaxation times of spins with different molecular environments, and therefore its variation could indicate a change in the balance between subpopulations of macromolecular spins. Conversely, in lesions, RM, T, F, RA, and lesion load significantly predicted disability only when combined together. This might reflect the complex interaction between demyelination, remyelination, gliosis, inflammation and axonal loss taking place within lesions. Copyright © 2009 John Wiley & Sons, Ltd.
Manganese‐enhanced MRI visualizes V1 in the non‐human primate visual cortex
Authors: Bock Nicholas A. , Kocharyan Ara , Silva Afonso C. 
Published: March 2009

AbstractMRI at 7 Tesla has been used to investigate the accumulation of manganese in the occipital cortex of common marmoset monkeys (Callithrix jacchus) after administering four fractionated injections of 30 mg/kg MnCl2 · 4H2O in the tail vein. We found a statistically significant decrease in T1 in the primary (V1) and secondary (V2) areas of the visual cortex caused by an accumulation of manganese. The larger T1 shortening in V1 (ΔT1 = 640 ms) relative to V2 (ΔT1 = 490 ms) allowed us to robustly detect the V1/V2 border in vivo using heavily T1‐weighted MRI. Furthermore, the dorso‐medial (DM) and middle‐temporal (MT) areas of the visual pathway could be identified by their T1‐weighted enhancement. We showed by comparison to histological sections stained for cytochrome oxidase (CO) activity that the extent of V1 is accurately identified throughout the visual cortex by manganese‐enhanced MRI (MEMRI). This provides a means of visualizing functional cortical regions in vivo and could be used in longitudinal studies of phenomena such as cortical plasticity, and for non‐destructive localization of cortical regions to guide in the implementation of functional techniques. Published in 2009 by John Wiley & Sons, Ltd.
Catalytic performance of chitosan‐Schiff base supported Pd/Co bimetallic catalyst for acrylamide with phenyl halide
Authors: Li‐xia Wang , Zi‐wei Wang , Guo‐song Wang , Xiao‐dong Lin , Jian‐guo Ren 
Published: March 2009

AbstractThe chitosan‐Schiff base supported palladium and cobalt bimetallic complex was synthesized in a simple method and characterized by Fourier‐transform infrared spectroscopy (FT‐IR), powder X‐ray diffraction (XRD), and X‐ray photoelectron spectra (XPS). It was found that the catalyst has great activity and stability in the coupling of acrylamide (AA) with the phenyl halide. The influence of various bimetallic catalysts, the different molar ratio of Co/Pd, the bases, the amount of the catalyst and base, and the molar ratio of iodobenzene/AA on the reaction were investigated. The results showed that the catalytic activity of the molar ratio of Co/Pd (3/1) was the best when the iodobenzene was used as a substrate. The yield of the cinnamamide did not change significantly after ten runs. It has been revealed that the catalyst was efficient for the reaction. Copyright © 2009 John Wiley & Sons, Ltd.
Conductive polymers/polyacrylonitrile composite fibers: Fabrication and properties
Authors: Xia Youyi , Lu Yun 
Published: March 2009

AbstractPolypyrrole/polyacrylonitrile, polyaniline/polyacrylonitrile, and poly(3,4‐ethylenedioxythiophene)/polyacrylonitrile composite fibres were fabricated successfully by in situ polymerization. The morphologic observations confirmed the uniformly‐covered polyacrylonitrile fiber surface by conductive conjugated polymers. These composite fibers exhibited conductivity in the range of 1.4 × 10−2 to 5.2 × 10−1 S cm−1. Improved thermal stability of the composite fibers was observed from thermogravimetric analysis results. Structural analysis indicated that the interactions of both hydrogen‐bonding and the electrostatic attraction existed between polyacrylonitrile chains and conjugated polymers. These novel composite fibers still possessed original fibrillar morphology and strength properties and showed a good stability to atmosphere and washing. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers