bluuebunny/crossref_metadata_2025_split huggingface dataset:
An automated GCxGC‐TOF‐MS protocol for batch‐wise extraction and alignment of mass isotopomer matrixes from differential 13C‐labelling experiments: a case study for photoautotrophic‐mixotrophic grown Chlamydomonas reinhardtii cells
Authors: Kempa Stefan , Hummel Jan , Schwemmer Thorsten , Pietzke Matthias , Strehmel Nadine , Wienkoop Stefanie , Kopka Joachim , Weckwerth Wolfram 
Published: February 2009

AbstractTwo dimensional gas chromatography coupled to time‐of‐flight mass spectrometry (GCxGC‐TOF‐MS) is a promising technique to overcome limits of complex metabolome analysis using one dimensional GC‐TOF‐MS. Especially at the stage of data export and data mining, however, convenient procedures to cope with the complexity of GCxGC‐TOF‐MS data are still in development. Here, we present a high sample throughput protocol exploiting first and second retention index for spectral library search and subsequent construction of a high dimensional data matrix useful for statistical analysis. The method was applied to the analysis of 13C‐labelling experiments in the unicellular green alga Chlamydomonas reinhardtii. We developed a rapid sampling and extraction procedure for Chlamydomonas reinhardtii laboratory strain (CC503), a cell wall deficient mutant. By testing all published quenching protocols we observed dramatic metabolite leakage rates for certain metabolites. To circumvent metabolite leakage, samples were directly quenched and analyzed without separation of the medium. The growth medium was adapted to this rapid sampling protocol to avoid interference with GCxGC‐TOF‐MS analysis. To analyse batches of samples a new software tool, MetMax, was implemented which extracts the isotopomer matrix from stable isotope labelling experiments together with the first and second retention index (RI1 and RI2). To exploit RI1 and RI2 for metabolite identification we used the Golm metabolome database (GMD [1] with RI1/RI2‐reference spectra and new search algorithms. Using those techniques we analysed the dynamics of 13CO2 and 13C‐acetate uptake in Chlamydomonas reinhardtii cells in two different steady states namely photoautotroph and mixotroph growth conditions. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of integrated application of chitosan coating and modified atmosphere packaging on overall quality retention in litchi cultivars
Authors: De Reuck Karen , Sivakumar Dharini , Korsten Lise 
Published: February 2009

AbstractBACKGROUND: The storage life of litchi is limited due to pericarp browning and decay. Modified atmosphere packaging (MAP) showed promising results for ensuring quality retention. However, to improve the efficiency of MAP the integrated treatment of a chitosan coating and MAP was investigated.RESULTS: The effect of chitosan (1.0 g L−1) + MAP was compared with MAP (control), and was effective in preventing decay, browning and retaining the pericarp colour in the cultivar McLean's Red. Chitosan (1.0 g L−1) + MAP significantly reduced polyphenol oxidase (PPO) and peroxidase (POD) activity, retained membrane integrity, anthocyanin content and prevented the decline of pericarp colour values during storage. The POD activity was greater than the PPO activity in the cultivars McLean's Red and Mauritius. The two cultivars differed in anthocyanin content and the activity of oxidation enzymes. The gas compositions within the packages were compared between chitosan at 1.0 g L−1 and 20.0 g L−1 concentration for both cultivars. Chitosan (20.0 g L−1) + MAP lowered the respiration during storage in both cultivars compared to 1.0 g L−1 + MAP.CONCLUSION: The McLean's Red cultivar is better suited for chitosan (1.0 g L−1) + MAP integrated treatment than is Mauritius in retaining overall quality. Copyright © 2009 Society of Chemical Industry
Relation between chemical composition of oak wood used in cooperage and sensory perception of model extracts
Authors: Prida Andrei , Heymann Hildegarde , Balanuta Anatol , Puech Jean‐Louis 
Published: February 2009

AbstractBACKGROUND: Oak extractive substances modify the aroma and taste of ‘oaked’ wines, with an increased intensity of sensory descriptors such as ‘oaky’, ‘spicy’, ‘vanilla’, ‘smoky’, etc. arising during barrel maturation. In this study the relationship between the chemical composition of untoasted oak wood and the sensory assessment of oak extract was investigated. Oak wood samples (140) were analysed both chemically (using gas chromatography/mass spectrometry after extraction with dichloromethane) and using sensory descriptive analysis of oak‐extracted model wine solutions.RESULTS: Oak samples from the USA, France and Eastern Europe had different chemical compositions in terms of principal odour‐active extractives, and this was reflected by perceived sensory differences.CONCLUSION: The major sensory differences were associated with cis‐whisky‐lactone concentrations of the wood extracts and were related to sensory descriptors such as coconut, caramel and milk. Other compounds studied (trans‐whisky‐lactone, eugenol and vanillin) were found to have a minor impact on sensory differences between samples in spite of their odour activity. This fact could be explained by the natural differences between samples not being sufficiently large to be perceived. The effects of aroma amplification and/or masking linked to the presence of other odorous chemicals could also explain these observations. Copyright © 2009 Society of Chemical Industry
Evaluating NIR instruments for quantitative and qualitative assessment of intact apple quality
Authors: Paz Patricia , Sánchez María‐Teresa , Pérez‐Marín Dolores , Guerrero José‐Emilio , Garrido‐Varo Ana 
Published: February 2009

AbstractBACKGROUND: In recent years, near‐infrared reflectance (NIR) instruments have undergone radical changes, becoming much more versatile, more portable, cheaper and better adapted to hostile working areas. In this study, three commercially available spectrophotometers were evaluated for the determination of quality (soluble solid content, firmness and shelf‐life) in intact apples. The three instruments used, which differ primarily in terms of measurement principle and wavelength range, were a scanning monochromator (SM) with a range of 400–2500 nm, a combination of diode array and scanning monochromator (DASM) with a range of 350–2500 nm and a diode array (DA) with a range of 900–1700 nm.RESULTS: A total of 334 apples (Malus domestica Borkh.), cvs Fuji and Golden Delicious, were used to build calibration models in different spectral regions and using various spectral signal pretreatments. The three NIR instruments evaluated provided good precision for soluble solid content, with r2 values between 0.90 and 0.94 and standard error of cross‐validation (SECV) values ranging from 0.51 to 0.68°Brix; however, firmness measurements were less precise in all three cases (r2 = 0.52–0.57, SECV = 8.28–8.83 N). The performance of the three instruments in classifying apples by shelf‐storage duration (0, 8 and 14 days) was studied using partial least squares discriminant analysis to develop classification models. A total of 86.1% of samples from the mixed‐cultivar group were correctly assigned, compared with 86.6% of samples from single‐cultivar groups.CONCLUSION: The results obtained suggest that, in general, the three NIR instruments tested provided a similar level of accuracy for the measurement of soluble solid content, firmness and shelf‐life, being slightly better the prediction models developed with the DASM spectrophotometer. Copyright © 2009 Society of Chemical Industry
Electrochemical Polymerization of Bis(3,4‐ethylenedioxythiophene)‐Substituted 1,4‐Diketo‐3,6‐diphenyl‐pyrrolo[3,4‐c]pyrrole (DPP) Derivative
Authors: Zhu Yu , Zhang Kai , Tieke Bernd 
Published: February 2009

AbstractSynthesis and electropolymerization of the new bisthienyl‐substituted diketopyrrolopyrrole monomer 1,4‐diketo‐2,5‐di‐hexyl‐3,6‐bis{[2‐(3',4'‐ethylenedi‐oxy)thienyl]phenyl}pyrrolo[3,4‐c]pyrrole (EDOT‐DPP‐EDOT) is reported. EDOT‐DPP‐EDOT exhibits a low oxidation potential of 0.67 V versus ferrocene and can be electropolymerized to form a stable, well adherent polymer thin film at the ITO anode. The polymer film is insoluble in organic solvents, non‐fluorescent, but exhibits reversible electrochromic properties with color changes from deep blue in the neutral state via transparent gray to purple red in the oxidized state. The reversibility in air is excellent.magnified image
Well‐Defined Crystalline TiO2 Nanoparticles Generated and Immobilized on a Colloidal Nanoreactor
Authors: Lu Yan , Hoffmann Martin , Yelamanchili Ram Sai , Terrenoire Alexandre , Schrinner Marc , Drechsler Markus , Möller Michael W. , Breu Josef , Ballauff Matthias 
Published: February 2009

AbstractWe synthesized well‐defined, crystalline TiO2 nanoparticles at room temperature by using spherical polyelectrolyte brush particles as a template. The template particles consist of a polystyrene core from which long chains of poly(styrene sodium sulfonate) are grafted. Tetraethylorthotitanate is hydrolyzed in the presence of brush particles leading to the formation of well‐dispersed TiO2 nanoparticles (d = 4∼12 nm). Wide‐angle X‐ray scattering demonstrates that anatase nanoparticles with high crystallinity have been generated at room temperature. The as‐prepared TiO2 nanocomposites present high photocatalytic activity for the degradation of Rhodamine B under UV irradiation. Finally, mesoporous TiO2 structures with defined pore size are formed after calcination.magnified image
Double‐porosity homogenization for perimeter functionals
Authors: Solci Margherita 
Published: February 2009

AbstractIn this paper we are concerned with the overall description of interfacial energies in a composite environment where the local properties of the media are characterized by a large variation of the values of surface tension (double‐porosity homogenization).We prove some asymptotic results in terms of Γ‐convergence for a sequence of functionals modelling these energies. We show the connection of the Γ‐limit with the geometry of the periodic ‘holes’ of the perforated domain, in particular investigating the relation with the Cheeger constant and the Cheeger set of a convex subset of ℝn.
General energy decay estimates of Timoshenko systems with frictional versus viscoelastic damping
Authors: Guesmia Aissa , Messaoudi Salim A. 
Published: February 2009

AbstractIn this paper we consider the following Timoshenko system:

with Dirichlet boundary conditions and initial data where a, b, g and h are specific functions and ρ1, ρ2, k1, k2 and L are given positive constants. We establish a general stability estimate using the multiplier method and some properties of convex functions. Without imposing any growth condition on h at the origin, we show that the energy of the system is bounded above by a quantity, depending on g and h, which tends to zero as time goes to infinity. Our estimate allows us to consider a large class of functions h with general growth at the origin. We use some examples (known in the case of wave equations and Maxwell system) to show how to derive from our general estimate the polynomial, exponential or logarithmic decay. The results of this paper improve and generalize some existing results in the literature and generate some interesting open problems. Copyright © 2009 John Wiley & Sons, Ltd.
A bonded joint finite element for a symmetric double lap joint subjected to mechanical and thermal loads
Authors: Gustafson Peter A. , Waas Anthony M. 
Published: February 2009

AbstractA bonded joint finite element (FE) for a symmetric double lap joint is developed that is capable of predicting field quantities in the lap region. The element is a hybrid method and incorporates features of classical analytical and numerical methods. The element stiffness and load vector formulations have unique, load dependent, non‐linear shape functions based on an analytical solution. The adaptive shape functions are formulated in terms of the dimensionless mechanical load fraction \documentclass{article}\footskip=0pc\pagestyle{empty}\begin{document}$(\bar{\bar{\phi}}_P)$\end{document} and total load \documentclass{article}\footskip=0pc\pagestyle{empty}\begin{document}$(\bar{\bar{\phi}}_{\rm {tot}})$\end{document} and are capable of predicting the thermal and mechanical load response. The bonded joint element has been implemented as a user element in the Abaqus® commercial FE code. A comparison of the stress predictions for the bonded joint element and a conventional 2D FE model is presented and are found to be in good agreement. Therefore, the element provides a computationally efficient and mesh‐independent stress prediction. The single element reproduces the analytical solution with minimal analyst input and can be easily incorporated into early design and sizing studies. Copyright © 2009 John Wiley & Sons, Ltd.
An enriched element‐failure method (REFM) for delamination analysis of composite structures
Authors: Sun X. S. , Tan V. B. C. , Liu G. , Tay T. E. 
Published: February 2009

AbstractThis paper develops an enriched element‐failure method for delamination analysis of composite structures. This method combines discontinuous enrichments in the extended finite element method and element‐failure concepts in the element‐failure method within the finite element framework. An improved discontinuous enrichment function is presented to effectively model the kinked discontinuities; and, based on fracture mechanics, a general near‐tip enrichment function is also derived from the asymptotic displacement fields to represent the discontinuity and local stress intensification around the crack‐tip. The delamination is treated as a crack problem that is represented by the discontinuous enrichment functions and then the enrichments are transformed to external nodal forces applied to nodes around the crack. The crack and its propagation are modeled by the ‘failed elements’ that are applied to the external nodal forces. Delamination and crack kinking problems can be solved simultaneously without remeshing the model or re‐assembling the stiffness matrix with this method. Examples are used to demonstrate the application of the proposed method to delamination analysis. The validity of the proposed method is verified and the simulation results show that both interlaminar delamination and crack kinking (intralaminar crack) occur in the cross‐ply laminated plate, which is observed in the experiment. Copyright © 2009 John Wiley & Sons, Ltd.
Pubic symphyseal face eburnation: an Egyptian sport story?
Authors: Judd M. A. 
Published: February 2009

AbstractStrenuous physical activity leaves scars on bone that attest to the demands of occupation, sport, aggression and recreation. During the assessment of 74 C‐Group Nubians from Hierakonpolis (Egypt) dated to the Egyptian Middle Kingdom–Second Intermediate Period (2080–1700 BC), robust muscle insertions along the ilia and ischia were observed among some adults. In addition, a disproportionate degeneration of the pubic symphyseal faces when compared to other age‐related features was also noted. In the case of one male (Burial 32), the pubic symphyseal faces were completely flattened and polished so that they resembled the eburnation that is pathognomic of osteoarthritis. Differential diagnoses are discussed and osteitis pubis, an increasingly diagnosed injury among modern athletes who participate in intense activity that involves running, kicking, twisting or leaping, is proposed as the most likely etiology. The exaggerated muscle insertions and pubic symphyseal wear, epitomised by the individual interred in Burial 32, are unique features that may be linked to the unexplained presence of this Nubian group deep in Egyptian territory during a period of political instability. Artefactual, artistic and documentary evidence records how the Egyptian pharaohs and elites conscripted Nubian athletes to the royal courts for staged contests and entertainment, part of a propaganda program engineered to reinforce among the general populace the dogma of Egyptian supremacy over the enemy. This Nubian community, serviced by Cemetery HK27C, may have functioned as a source for individuals skilled in athletics or other activities that required exceptional physical dexterity. The extraordinary modification of these pubic symphyseal faces underscores the importance of recognising paleopathological conditions that may further confound current macroscopic methods used to ascertain the chronological age of an individual. Copyright © 2009 John Wiley & Sons, Ltd.
Preparation and characterization of polyurethan‐block‐poly(trifluoro‐ propylmethyl)siloxane elastomers
Authors: Shi Zhendong , Wang Xinling 
Published: February 2009

AbstractA series of polyurethane‐block‐poly(trifluoropropylmethyl)siloxane (PUFS) elastomers were prepared via a two‐step process from toluenediisocyanate (TDI), α ω‐bis(3‐aminopropyldiethoxylsilane) poly(trifluoropropylmethyl)siloxane (APFS), and poly(tetramethylene oxide) (PTMO). The PUFS films were formed through moisture curing and characterized by DSC, DMTA, TGA, mechanical testing, and water contact angle. It was found that the extent of microphase separation of the PUFS system would increase with the increase in APFS content, and result in the decrease in the tensile strength and the thermal stability. On the other hand, the crosslink density of the PUFS system would apparently increase with the increase in the TDI content, which reduced the microphase separation and improved the tensile properties and the thermal stability of the PUFS elastomers. Copyright © 2009 John Wiley & Sons, Ltd.
Morphology of phase‐separated thermotropic layers based on UV cured acrylate resins
Authors: Resch Katharina , Wallner Gernot M. 
Published: February 2009

AbstractIn this paper, relationships between the scattering domain parameters (size and shape) and the light‐shielding properties of thermotropic systems with fixed domains (TSFD) are established. Specific focus is given to the effect of additive type on the formation of scattering domain size. Various functional layers are prepared by a variation of thermotropic additives. Scattering domains are investigated applying high resolution Atomic Force Microscopy (AFM) in a phase imaging mode. Thermotropic layers formulated with additive types exhibiting a short chain length display roughly spherical scattering particles with dimensions between 0.5 and 3 µm and a moderate reduction in hemispheric solar transmittance along with a significant increase in diffuse solar transmittance above the switching threshold. Additive types with long‐chain molecules develop anisotropic scattering domains resembling distorted disks with a diameter up to 50 µm and a thickness between 100 and 400 nm. Disk‐like scattering features yield enhanced light‐shielding properties. Copyright © 2009 John Wiley & Sons, Ltd.
Irradiation‐induced grafting of acrylonitrile onto activated carbon fiber
Authors: Zhang Sujuan , Zhang Qikun , Chen Shuixia , Yuan Qingyu , Li Peiyuan 
Published: February 2009

AbstractViscose‐based activated carbon fiber (VACF) was modified with acrylonitrile (AN) by γ‐irradiation‐induced grafting polymerization. Effects of the grafting conditions, such as concentrations of AN and divinylbenzene (DVB), pH value, and solvent on the grafting process were studied. The physicochemical properties of the fibers were characterized. The results show that AN can be effectively grafted onto the surface of VACF with the addition of DVB. The grafting yield is higher than 12% according to thermogravimetric (TG) analysis. The study shows that DVB can improve the grafting degree of AN in the form of grafting chains or agglomerate materials. After grafting modification, VACF shows a small decrease in the specific surface area. Copyright © 2009 John Wiley & Sons, Ltd.
Development of the vertebrate central nervous system: formation of the neural tube
Authors: Greene Nicholas D. E. , Copp Andrew J. 
Published: February 2009

AbstractThe developmental process of neurulation involves a series of coordinated morphological events, which result in conversion of the flat neural plate into the neural tube, the primordium of the entire central nervous system (CNS). Failure of neurulation results in neural tube defects (NTDs), severe abnormalities of the CNS, which are among the commonest of congenital malformations in humans. In order to gain insight into the embryological basis of NTDs, such as spina bifida and anencephaly, it is necessary to understand the morphogenetic processes and molecular mechanisms underlying neural tube closure. The mouse is the most extensively studied mammalian experimental model for studies of neurulation, while considerable insight into underlying developmental mechanisms has also arisen from studies in other model systems, particularly birds and amphibians. We describe the process of neural tube formation, discuss the cellular mechanisms involved and highlight recent findings that provide links between molecular signaling pathways and morphogenetic tissue movements. Copyright © 2009 John Wiley & Sons, Ltd.
Rhabdomyolysis reports show interaction between simvastatin and CYP3A4 inhibitors
Authors: Rowan Christopher , Brinker Allen D. , Nourjah Parivash , Chang Jennie , Mosholder Andrew , Barrett Jeffrey S. , Avigan Mark 
Published: February 2009

AbstractPurposeTo assess spontaneous reports of rhabdomyolysis associated with simvastatin (SV) and pravastatin (PV) for evidence of CYP3A4 interaction. Clinical trial results advocate cholesterol lowering in high‐risk patients including diabetics and the elderly. Given the association between advancing age, metabolic, and cardiovascular disease, many patients are treated with concomitant medications upon statin initiation. Although statins are generally safe, minor and severe adverse reactions arise, especially when given to patients taking concomitant medications that inhibit the statin clearance and lead to increased statin plasma concentration.MethodsWe conducted a comparative case series of rhabdomyolysis reports associated with SV and PV. Domestic spontaneous reports were obtained from the FDA's Adverse Event Reporting System (AERS). Drug utilization data were obtained from IMS HEALTH and the National Ambulatory Medical Care Survey (NAMCS). Adverse event reporting rates (AER) and ratios (AERR) of rhabdomyolysis associated with SV and PV—with and without stratification by CYP3A4 inhibitor concomitancy were determined.ResultsStratification by CYP3A4 inhibitor concomitancy did not change the rhabdomyolysis AER for PV with or without a CYP3A4 inhibitor (2.4 cases and 3.1 cases per 10 million Rx, respectively). However, stratification of SV reports with or without a concomitant CYP3A4 inhibitor resulted in a rhabdomyolysis AER (38.4 and 6.0 cases per 10 million Rx, respectively). The corresponding AERR with or without a CYP3A4 inhibitor were 0.77 for PV and 6.43 for SV.ConclusionsSpontaneous adverse event reports provide evidence of increased risk for rhabdomyolysis based on interaction between SV and selected CYP3A4 inhibitors. Copyright © 2009 John Wiley & Sons, Ltd.