bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contribution of two approaches using electrospray ionization with multi‐stage mass spectrometry for the characterization of linseed oil
Authors: Loutelier‐Bourhis Corinne , Zovi Ornella , Lecamp Laurence , Bunel Claude , Lange Catherine M. 
Published: November 2009

AbstractA detailed characterization of triacylglycerols (TAGs) present in linseed oil samples from a local producer was performed using electrospray ionization and two mass spectrometric approaches; direct infusion multi‐stage mass spectrometry (MSn) experiments and liquid chromatography/tandem mass spectrometry (LC/MS/MS) using non‐aqueous reversed‐phase chromatographic conditions. The combination of both approaches permitted the identification of 26 TAGs. Comparison of the two analytical approaches showed that discrimination of regioisomers was achieved from MS3 data while other isobaric species were separated and identified by LC/MS/MS analysis. The results we obtained were also compared with those previously reported. The TAG composition of the studied linseed oil is qualitatively identical to that of linseed oils from various sources in Europe, Canada, Argentina or India. However, a few differences were observed with regard to the proportions of some TAGs; these can be explained by variations in the culture conditions, climate, and variety of the seeds. Copyright © 2009 John Wiley & Sons, Ltd.
Combined chemical and topographic imaging at atmospheric pressure via microprobe laser desorption/ionization mass spectrometry–atomic force microscopy
Authors: Bradshaw James A. , Ovchinnikova Olga S. , Meyer Kent A. , Goeringer Douglas E. 
Published: November 2009

AbstractThe operational characteristics and imaging performance are described for a new instrument comprising an atomic force microscope coupled with a pulsed laser and a linear ion trap mass spectrometer. The operating mode of the atomic force microscope is used to produce topographic surface images having sub‐micrometer spatial and height resolution. Spatially resolved mass spectra of ions, produced from the same surface via microprobe‐mode laser desorption/ionization at atmospheric pressure, are also used to create a 100 × 100 µm chemical image. The effective spatial resolution of the image (∼2 µm) was constrained by the limit of detection (estimated to be 109–1010 molecules) rather than by the diameter of the focused laser spot or the step size of the sample stage. The instrument has the potential to be particularly useful for surface analysis scenarios in which chemical analysis of targeted topographic features is desired; consequently, it should have extensive application in a number of scientific areas. Because the number density of desorbed neutral species in laser desorption/ionization is known to be orders‐of‐magnitude greater than that of ions, it is expected that improvements in imaging performance can be realized by implementation of post‐ionization methods. Published in 2009 by John Wiley & Sons, Ltd.
Isotope dilution method for the assay of rotenone in olive oil and river waters by liquid chromatography/multiple reaction monitoring tandem mass spectrometry
Authors: Mazzotti Fabio , Di Donna Leonardo , Attya Mohamed , Gabriele Bartolo , Fazio Alessia , Sindona Giovanni 
Published: November 2009

AbstractA new approach for the assay of rotenone (1) by isotope dilution mass spectrometry is presented. The extreme toxicity of rotenone, a natural phytodrug with insecticidal and piscicidal activity, recently banned by national and international environmental protection agencies, calls for the development of sensitive and accurate methods of analyses. Accordingly, the proposed protocol is based on the availability of the labeled internal standard rotenone‐d3 (3) which can be conveniently prepared by consecutive and specific mono‐O‐demethylation, and remethylation with methyl iodide‐d3. The sensitivity of the method is confirmed by the very low limit of detection (LOD) and quantitation (LOQ) values achieved in the assay of 1 in two distinct fortified matrices, and is further supported by the observed accuracy values. Copyright © 2009 John Wiley & Sons, Ltd.
Advertising effectiveness and spillover: simulating strategic interaction using advertising
Authors: Brady Malcolm P. 
Published: November 2009

AbstractThis paper reports on a model of advertising‐driven competition based on the Cournot analytical duopoly model using a system dynamics approach. The paper discusses the feedback loops that are derived from the analytical equations and shows simulation results for a number of competitive scenarios. The paper identifies and discusses three different inter‐firm feedback loops. The scenarios demonstrate that small changes in model parameter values can lead to significant differences in firm and industry behaviour; a bifurcation in duopoly behaviour at low and high levels of advertising effectiveness is demonstrated. The simulation model demonstrates that positive spillover (cooperation) reduces the impact of advertising and supports the free‐rider hypothesis where advertising is cooperative. The model also demonstrates that negative spillover (predation) increases the impact of advertising when both firms advertise. The paper proposes simulation as an alternative to the differential game approach when studying dynamic economic systems. Copyright © 2009 John Wiley & Sons, Ltd.
Angular accuracy and the comparison of two methods for determining the surface normal in a Kratos Axis Ultra X‐ray photoelectron spectrometer
Authors: Seah M. P. , Spencer S. J. 
Published: November 2009

AbstractAn investigation of the calibration of the sample orientation with respect to the spectrometer input lens electron optical axis is reported using two proposed methods: the crystal axis method (CAM) and the overlayer thickness consistency method (OTCM). The study is conducted in a Kratos Axis Ultra X‐ray photoelectron spectrometer. First, the emission angle settings of the sample holder are calibrated with respect to the mechanical axis. It is found, using a laser beam system, that there is a significant error in the instrument's sample stage tilt angle calibration which increases with the emission angle with a maximum error of 5°. This is attributed to the use of a low‐torque magnetic rotary drive that is increasingly offset by the restoring torque from internal cooling coils. After calibration of the tilt scale, the zero angle of emission with respect to the electron optical axis, using the CAM, is found to be 0.26° ± 0.07°. Using the OTCM, it is found that it is more likely that the consistency should be homogenised around 0° emission rather than over the 10° –40° range proposed. The exact emission angle for homogenisation is unclear, and present calculations of electron transport are insufficiently accurate to define this. The precise way to use the OTCM is, therefore, unknown. It is recommended that only the CAM be used, that analysts check that the sample stage tilts at a rate of 1° per 1° set and that manufacturers consider these angles carefully in instrument design. © Crown copyright 2009. Reproduced with the permission of Her Majesty's Stationery Office. Published by JohnWiley & Sons, Ltd.
18O/16O isotopic separation in anodic tantala films by glow discharge time‐of‐flight mass spectrometry
Authors: Tempez A. , Canulescu S. , Molchan I. S. , Döbeli M. , Whitby J. A. , Lobo L. , Michler J. , Thompson G. E. , Bordel N. , Chapon P. , Skeldon P. , Delfanti I. , Tuccitto N. , Licciardello A. 
Published: November 2009

AbstractGlow discharge mass spectrometry has been widely used for trace and ultra‐trace element analysis of high‐purity alloys. A novel pulsed radio frequency glow discharge time‐of‐flight mass spectrometer (rf GD TOFMS) has been developed that retains the pulsed radio frequency analytical ion source to provide ion signal enhancement due to processes involving Penning ionisation. A time‐resolved detection mode has been implemented to sample the afterglow regime of the pulse profile, corresponding to the highest ion signal intensities. Here, the performance of rf GD TOFMS in isotope differentiation is discussed. Anodic tantala films, comprising 18O‐rich layers of controlled thicknesses and locations, were formed by appropriate combination of anodising of tantalum in electrolytes enriched with 18O isotopes and of natural O isotopic abundance. Transmission electron microscopy (TEM) and radio frequency glow discharge optical emission spectrometry (rf GD OES) analyses were performed to examine the morphology and elemental distributions of the specimens, while the content of 18O in the 18O‐rich layers was determined by elastic recoil detection analysis(ERDA). In pulsed rf GD TOFMS analysis, characteristic ionic species formed in the glow discharge allows differentiation of 18O‐rich layers. Particularly, the location of 18O‐rich layers was determined from the 16O18O and Ta18O ion signals at masses m/z 34 and 199, respectively. The locations of 18O‐rich layers in anodic films, controlled by the selected anodising conditions, were probed precisely. The 18O profiles in anodic tantala were directly compared with those obtained by dual beam time‐of‐flight SIMS. Copyright © 2009 John Wiley & Sons, Ltd.
Monitoring risk response actions for effective project risk management
Authors: Kujawski Edouard , Angelis Diana 
Published: November 2009

AbstractComplex projects typically involve high‐consequence, project‐specific risks that require detailed analysis and for which risk response actions (RRAs) need to be developed and implemented. The risk picture is dynamic. The sources and consequences of risks evolve and change over the project lifecycle; thus, it is necessary to constantly monitor risk. RRAs that do not keep pace with the changing project situation are a major cause of risk management failures. This paper extends traditional cost risk analysis from a purely macroscopic perspective by evaluating and tracking project‐specific risks and RRAs at the microscopic level. The key elements of the method are (i) develop risk scenarios, (ii) model them using generalized decision trees, and (iii) quantify the risks using Monte Carlo simulation. For each risk the probability and cost values are conditional on the specific RRA and the preceding outcomes. The use of fractional factorial design provides a subset of all possible RRA combinations for efficiently determining the preferred total project RRA solution. Risk curves are generated to provide the necessary information to analyze, track, and manage the performance of the selected RRAs over time. Project managers and team leaders can use this information to dynamically manage the RRAs to keep pace with the changing project situation, thereby increasing the probability of project success in a cost‐effective manner. The approach is detailed using a realistic but simplified case of a project examined first with one and then expanded to three technical risks. © 2009 Wiley Periodicals, Inc. Syst Eng 13
Experience from introducing Unified Modeling Language/Systems Modeling Language at Saab Aerosystems
Authors: Andersson Henric , Herzog Erik , Johansson Gert , Johansson Olof 
Published: November 2009

AbstractA Unified Modeling Language/Systems Modeling Language (UML/SysML) subset was the modeling notation selected for an aerospace systems engineering project at Saab Aerosystems. In this paper, the rationale for selecting UML/SysML is given, along with a description of the situation at the project planning stage regarding business conditions, method and tools support. The usage of use case, sequence, and activity diagrams are described as well as definition of functional chains with SysML. Furthermore, the connections to system implementation activities including code generation and simulation are discussed. The advantages and disadvantages of using UML/SysML from experience in an industrial context are reported. It is also described how UML/SysML is related to industrial research projects in the Model Based Systems Engineering (MBSE) methods and tools area. Introducing UML/SysML with a methodology and a supporting toolset in an operative organization require a clear strategy, including planning, just‐in‐time training, and mentor support. Finally, industrial needs for further development of SysML are discussed. © 2009 Wiley Periodicals, Inc.
The human c‐fos and TNFα AU‐rich elements show different effects on mRNA abundance and protein expression depending on the reporter in the yeast Pichia pastoris
Authors: Lautz Thomas , Stahl Ulf , Lang Christine 
Published: November 2009

AbstractAU‐rich elements (AREs) are located in the 3′ untranslated region (3′ UTR) of their host genes and tightly regulate mRNA degradation and expression. Examples for this kind of regulation are the human proto‐oncogene c‐fos and the cytokine TNFα. Despite large effort in this field, the exact mechanism of ARE‐mediated mRNA turnover remains unclear. In this work we analysed the effects of c‐fos‐ and TNFα AREs on mRNA abundance and protein expression of selected human cDNAs in the yeast Pichia pastoris. This yeast is exceedingly well known for its excellent protein production capacity; however, ARE‐like mechanisms have not been studied in this yeast to date. Interestingly, we observed both stabilizing and destabilizing effects of the c‐fos ARE, whereas the TNFα ARE has a destabilizing or expression‐reducing function in all tested cDNAs. Based on this observation, we introduced a number of single‐point mutations upstream of the introduced c‐fos ARE into the 3′ UTR of a single cDNA in order to demonstrate the importance of ARE‐flanking sequences for their own regulation. In conclusion, we illustrate that the analysis of ARE‐mediated effects on mRNA abundance and protein expression of a reporter depends on the sequence of the reporter itself as well as the ARE‐surrounding sequences within the 3′ UTR. For this reason, we question whether already established reporter constructs in other cellular systems display the true type of regulation of the tested AREs for its original host gene. Finally, we propose that AREs should be analysed in their native sequence context. Copyright © 2009 John Wiley & Sons, Ltd.
Paracoccin from Paracoccidioides brasiliensis; purification through affinity with chitin and identification of N‐acetyl‐β‐D‐glucosaminidase activity
Authors: dos Reis Almeida Fausto Bruno , de Oliveira Leandro Licursi , de Sousa Marcelo Valle , Barreira Maria Cristina Roque , Hanna Ebert Seixas 
Published: November 2009

AbstractThe dimorphic fungus Paracoccidioides brasiliensis is the causative agent of paracoccidioidomycosis, the most frequent systemic mycosis in Latin America. Our group has been working with paracoccin, a P. brasiliensis lectin with MM 70 kDa, which is purified by affinity with immobilized N‐acetylglucosamine (GlcNAc). Paracoccin has been described to play a role in fungal adhesion to extracellular matrix components and to induce high and persistent levels of TNFα and nitric oxide production by macrophages. In the cell wall, paracoccin colocalizes with the β‐1,4‐homopolymer of GlcNAc into the budding sites of the P. brasiliensis yeast cell. In this paper we present a protocol for the chitin‐affinity purification of paracoccin. This procedure provided higher yields than those achieved by means of the technique based on the affinity of this lectin with GlcNAc and had an impact on downstream assays. SDS–PAGE and Western blot analysis revealed similarities between the N‐acetylglucosamine‐ and chitin‐bound fractions, confirmed by MALDI–TOF–MS of trypsinic peptides. Western blot of two‐dimensional gel electrophoresis of the yeast extract showed a major spot with Mr 70 000 and pI approximately 5.63. Morevover, an N‐acetyl‐β‐D‐glucosaminidase activity was reported for paracoccin, thereby providing new insights into the mechanisms that lead to cell wall remodelling and opening new perspectives for its structural characterization. Copyright © 2009 John Wiley & Sons, Ltd.
Dosage‐dependent roles of the Cwt1 transcription factor for cell wall architecture, morphogenesis, drug sensitivity and virulence in Candida albicans
Authors: Moreno Inmaculada , Martinez‐Esparza María , Laforet Leslie Carolina , Sentandreu Rafael , Ernst Joachim F. , Valentin Eulogio 
Published: November 2009

AbstractThe Cwt1 transcription factor is involved in cell wall architecture of the human fungal pathogen Candida albicans. We demonstrate here that deficiency of Cwt1 leads to decreased β1,6‐glucan in the cell wall, while mannoproteins are increased in the cell wall of exponentially growing cells and are released into the medium of stationary phase cells. Hyphal morphogenesis of cwt1 mutants is reduced on the surfaces of some inducing media. Unexpectedly, the CWT1/cwt1 heterozygous strains shows some stronger in vitro phenotypes compared to the homozygous mutant. The heterozygous but not the homozygous strain is also strongly impaired for its virulence in a mouse model of systemic infection. We suggest that an intermediate dosage of Cwt1 affects phenotypes profoundly, while its complete absence may elicit compensatory responses of C. albicans. Copyright © 2009 John Wiley & Sons, Ltd.
The role of two putative nitroreductases, Frm2p and Hbn1p, in the oxidative stress response in Saccharomyces cerevisiae
Authors: de Oliveira Iuri Marques , Zanotto‐Filho Alfeu , Moreira José Cláudio Fonseca , Bonatto Diego , Henriques João Antonio Pêgas 
Published: November 2009

AbstractThe nitroreductase family is comprised of a group of FMN‐ or FAD‐dependent enzymes that are able to metabolize nitrosubstituted compounds using the reducing power of NAD(P)H. These nitroreductases can be found in bacterial species and, to a lesser extent, in eukaryotes. There is little information on the biochemical functions of nitroreductases. Some studies suggest their possible involvement in the oxidative stress response. In the yeast Saccharomyces cerevisiae, two nitroreductase proteins, Frm2p and Hbn1p, have been described. While Frm2p appears to act in the lipid signalling pathway, the function of Hbn1p is completely unknown. In order to elucidate the functions of Frm2p and Hbn1p, we evaluated the sensitivity of yeast strains, proficient and deficient in both oxidative stress proteins, for respiratory competence, antioxidant‐enzyme activities, intracellular reactive oxygen species (ROS) production and lipid peroxidation. We found reduced basal activity of superoxide dismutase (SOD), ROS production, lipid peroxidation and petite induction and higher sensitivity to 4‐nitroquinoline‐oxide (4‐NQO) and N‐nitrosodiethylamine (NDEA), as well as higher basal activity of catalase (CAT) and glutathione peroxidase (GPx) and reduced glutathione (GSH) content in the single and double mutant strains frm2Δ and frm2Δ hbn1Δ. These strains exhibited less ROS accumulation and lipid peroxidation when exposed to peroxides, H2O2 and t‐BOOH. In summary, the Frm1p and Hbn1p nitroreductases influence the response to oxidative stress in S. cerevisae yeast by modulating the GSH contents and antioxidant enzymatic activities, such as SOD, CAT and GPx. Copyright © 2009 John Wiley & Sons, Ltd.
Evolutionary ecology of inducible morphological plasticity in predator–prey interaction: toward the practical links with population ecology
Authors: Kishida Osamu , Trussell Geoffrey C. , Mougi Akihiko , Nishimura Kinya 
Published: November 2009

AbstractThe outcome of species interactions is often strongly influenced by variation in the functional traits of the individuals participating. A rather large body of work demonstrates that inducible morphological plasticity in predators and prey can both influence and be influenced by species interaction strength, with important consequences for individual fitness. Much of the past research in this area has focused on the ecological and evolutionary significance of trait plasticity by studying single predator–prey pairs and testing the performance of individuals having induced and noninduced phenotypes. This research has thus been critical in improving our understanding of the adaptive value of trait plasticity and its widespread occurrence across species and community types. More recently, researchers have expanded this foundation by examining how the complexity of organismal design and community‐level properties can shape plasticity in functional traits. In addition, researchers have begun to merge evolutionary and ecological perspectives by linking trait plasticity to community dynamics, with particular attention on trait‐mediated indirect interactions. Here, we review recent studies on inducible morphological plasticity in predators and their prey with an emphasis on internal and external constraints and how the nature of predator–prey interactions influences the expression of inducible phenotypes. In particular, we focus on multiple‐trait plasticity, flexibility and modification of inducible plasticity, and reciprocal plasticity between predator and prey. Based on our arguments on these issues, we propose future research directions that should better integrate evolutionary and population studies and thus improve our understanding of the role of phenotypic plasticity in predator–prey population and community dynamics.
Estimation of epiphytic biomass and nutrient pools in the subtropical montane cloud forest in the Ailao Mountains, south‐western China
Authors: Chen Lin , Liu Wen‐yao , Wang Gao‐sheng 
Published: November 2009

AbstractCanopy organic matter (COM) composed of epiphyte community exists as a complex subsystem in the montane cloud forest (MCF). We estimated the biomass and nutrient pools of COM in a subtropical MCF in the Ailao Mountain National Nature Reserve (NNR). The diameter at breast height (DBH) of host trees was the best parameter in the estimation of epiphytic biomass, compared to the height (H) of host trees and the combination of both parameters. The effect of host tree species was negligible in the estimation. Therefore, it was concluded that the DBH data of all trees of a forest regardless of species was a suitable index for the non‐destructive estimation of epiphytic biomass in field surveys, especially for investigations of larger study areas. According to species‐specific equations, the total COM biomass was estimated to be 2,261 ± 537 (SD) kg ha−1, which was dominated by bryophytes (73.6%) and canopy humus (13.9%). The greatest proportion of COM was located on the inner branches (52.2%), followed by outer branches, trunks, the understory, and branch junctions. The nutrient pools (mean ± SD, kg ha−1) of the COM were: N = 37.9 ± 9.0, P = 1.97 ± 0.47, K = 9.6 ± 2.3, Ca = 9.6 ± 2.3, Mg = 2.64 ± 0.63 and Na = 0.25 ± 0.06. Assessments of epiphytic biomass and nutrient capital supported the idea that the canopy subsystem holds a substantial pool of nutrients, especially when compared to the labile components of the forest ecosystem.
Use of the SAW Sensor Electronic Nose for Detecting the Adulteration of Virgin Coconut Oil with RBD Palm Kernel Olein
Authors: Marina A. M. , Che Man Y. B. , Amin I. 
Published: November 2009

AbstractAn electronic nose (zNose™) was applied to the detection of adulteration of virgin coconut oil. The system, which is based on a surface acoustic wave sensor was used to generate a pattern of volatile compounds present in the samples. Virgin coconut oil was mixed with refined, bleached and deodorized palm kernel olein at a level of adulteration from 1 to 20% (wt/wt). Adulterant peaks were identified from the chromatogram profile and fitted to a curve using linear regression. The best relationship (R2 = 0.91) was obtained between the peak tentatively identified as methyl dodecanoate and the percentage of palm kernel olein added. Pearson's correlation coefficients (r) of 0.92 and 0.89 were obtained between adulterant peak methyl dodecanoate and of the iodine and peroxide values, respectively. Principal component analysis (PCA) was used to differentiate between pure and adulterated samples. The PCA provided good differentiation of samples with 74% of the variation accounted for by PC 1 and 17% accounted for by PC 2. Pure samples formed a separate cluster from all of the adulterated samples.