bluuebunny/crossref_metadata_2025 huggingface dataset:
Two organic‐inorganic hybrids with Keggin polyanions
Authors: Ma Huiyuan , Wang Xiaodan , Wang Fuping , Wu Lizhou
Published: October 2007

Two new Keggin polyoxometalates [Co(phen)3]2[SiW12O40]·6H2O (1) and (ppy)6 H4SiMo12O40·0.4H2O (2) (phen = 1,10′‐phenanthroline, ppy = 4‐(5‐phenylpyridin‐2‐yl)pyridine) have been synthesized by the hydrothermal method. Single crystal X‐ray analysis revealed that compound 1 crystallizes in the monoclinic crystal system with cell parameters of a = 13.344(2) Å, b = 17.191(3) Å, c = 22.002(4) Å, α = 90.00°, β = 99.566(2)°, γ = 90.00°, V = 4977 Å3, Z = 2, and compound 2 crystallizes in the triclinic crystal system with cell parameters of a = 11.297(2) Å, b = 12.341(3) Å, c = 19.354(4) Å, α = 107.60(3)°, β = 95.80(3)°, γ = 94.16(3)°, V = 2543.7(9) Å3, Z = 1. Both 1 and 2 represent organic ligand molecules and inorganic Keggin anions, which are further interconnected to a 3D framework by supramolecular interactions. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Serosal mesothelium retains vasculogenic potential
Authors: Kawaguchi Michiya , Bader David M. , Wilm Bettina
Published: October 2007

Mesothelia comprise the epithelial covering of coelomic organs and line the cavities in which they are housed. Mesothelia contribute to the vasculature of the heart and the intestinal tract by developmental processes of epithelial–mesenchymal transition (EMT), migration, and differentiation into endothelial cells, vascular smooth muscle cells, and pericytes. Here, we establish a novel in vitro system to analyze the differentiative potential of mesothelia. Using explants from serosal mesothelium (the mesothelial covering of the gut), we demonstrate that much of the developmental program observed in embryonic mesothelia is retained in the adult structure. Namely, processes of epithelial spreading, EMT, and differentiation into smooth muscle cells from these cells are observed. Interestingly, we were unable to stimulate endothelial cell differentiation using serum or various signaling factors. Taken together, these data reveal that differentiated serosal cells retain vasculogenic potential and provide a generalizable model for future studies on the developmental and differentiative capacity of the mesothelial cell type. Developmental Dynamics 236:2973–2979, 2007. © 2007 Wiley‐Liss, Inc.
Caenorhabditis elegans germ line: A model for stem cell biology
Authors: Albert Hubbard E. Jane
Published: October 2007

Like many stem cell systems, the Caenorhabditis elegans germ line contains a self‐renewing germ cell population that is maintained by a niche. Although the exact cellular mechanism for self‐renewal is not yet known, three recent studies shed considerable light on the cell cycle behavior of germ cells, including a support for significant and plastic renewal potential. This review brings together the results of the three recent cell‐based studies, places them in the context of previous work, and discusses future perspectives for the field. Developmental Dynamics 236:3343–3357, 2007. © 2007 Wiley‐Liss, Inc.
Muscle stem cells and model systems for their investigation
Authors: Figeac Nicolas , Daczewska Malgorzata , Marcelle Christophe , Jagla Krzysztof
Published: October 2007

Stem cells are characterized by their clonal ability both to generate differentiated progeny and to undergo self‐renewal. Studies of adult mammalian organs have revealed stem cells in practically every tissue. In the adult skeletal muscle, satellite cells are the primary muscle stem cells, responsible for postnatal muscle growth, hypertrophy, and regeneration. In the past decade, several molecular markers have been found that identify satellite cells in quiescent and activated states. However, despite their prime importance, surprisingly little is known about the biology of satellite cells, as their analysis was for a long time hampered by a lack of genetically amenable experimental models where their properties can be dissected. Here, we review how the embryonic origin of satellite cells was discovered using chick and mouse model systems and discuss how cells from other sources can contribute to muscle regeneration. We present evidence for evolutionarily conserved properties of muscle stem cells and their identification in lower vertebrates and in the fruit fly. In Drosophila, muscle stem cells called adult muscle precursors (AMP) can be identified in embryos and in larvae by persistent expression of a myogenic basic helix–loop–helix factor Twist. AMP cells play a crucial role in the Drosophila life cycle, allowing de novo formation and regeneration of adult musculature during metamorphosis. Based on the premise that AMPs represent satellite‐like cells of the fruit fly, important insight into the biology of vertebrate muscle stem cells can be gained from genetic analysis in Drosophila. Developmental Dynamics 236:3332–3342, 2007. © 2007 Wiley‐Liss, Inc.
Genes involved in the RNA interference pathway are differentially expressed during sea urchin development
Authors: Song Jia L. , Wessel Gary M.
Published: October 2007

RNA‐mediated interference (RNAi) is a conserved gene silencing mechanism that involves double‐stranded RNA as a signal to trigger the sequence‐specific degradation of target mRNA, resulting in posttranscriptional silencing and/or translational repression. Bioinformatic searches in the sea urchin genome database identified homologs of Drosha, DGCR5, Dicer, TRBP, Exportin‐5, and Argonautes. Quantitative, real‐time polymerase chain reaction indicated that all mRNA accumulate in eggs and in variable levels throughout early development. Whole‐mount in situ RNA hybridization showed that all of the important players of the RNAi silencing pathway have abundant mRNA accumulation in oocytes and eggs, but have distinct spatial and temporal expression patterns throughout development. Sequence analysis revealed that each of the four Argonautes examined contain conserved residues important for RNAseH activity within the Piwi domain. This study elucidated that genes involved in the RNAi silencing pathway have dynamic expression and, thus, may have regulatory roles during germ cell development and embryogenesis. Developmental Dynamics 236:3180–3190, 2007. © 2007 Wiley‐Liss, Inc.
High‐frequency ultrasonographic imaging of avian cardiovascular development
Authors: McQuinn Tim C. , Bratoeva Momka , DeAlmeida Angela , Remond Mathieu , Thompson Robert P. , Sedmera David
Published: October 2007

The chick embryo has long been a favorite model system for morphologic and physiologic studies of the developing heart, largely because of its easy visualization and amenability to experimental manipulations. However, this advantage is diminished after 5 days of incubation, when rapidly growing chorioallantoic membranes reduce visibility of the embryo. Using high‐frequency ultrasound, we show that chick embryonic cardiovascular structures can be readily visualized throughout the period of Stages 9–39. At most stages of development, a simple ex ovo culture technique provided the best imaging opportunities. We have measured cardiac and vascular structures, blood flow velocities, and calculated ventricular volumes as early as Stage 11 with values comparable to those previously obtained using video microscopy. The endocardial and myocardial layers of the pre‐septated heart are readily seen as well as the acellular layer of the cardiac jelly. Ventricular inflow in the pre‐septated heart is biphasic, just as in the mature heart, and is converted to a monophasic (outflow) wave by ventricular contraction. Although blood has soft‐tissue density at the ultrasound resolutions and developmental stages examined, its movement allowed easy discrimination of perfused vascular structures throughout the embryo. The utility of such imaging was demonstrated by documenting changes in blood flow patterns after experimental conotruncal banding. Developmental Dynamics 236:3503–3513, 2007. © 2007 Wiley‐Liss, Inc.
Motor performance and dyslexia in a national cohort of 10‐year‐old children
Authors: Haslum M. N. , Miles T. R.
Published: October 2007

Data from the 10‐year follow‐up of the 1970 British Births Survey were examined for associations between motor performance and dyslexia. Five tests of motor performance were used: (a) balancing on one leg, (b) throwing a ball in the air, clapping and catching it, (c) walking backwards, (d) sorting matches and (e) graphaesthesia (recognizing shapes drawn on the palm of the hand). These tests were given to 12 950 children aged between 10 and 11 years old. The cohort was divided into nine groups based on three levels of literacy achievement and three levels of possible indicators of dyslexia. The group with the most severe underachievement and most possible indicators (children most likely to be severely dyslexic) comprised about 2% of the total. Of this group, 35.3% failed one motor test and 16.4% failed more than one (51.7% in total), compared with 26.8% and 7.7% of normal achievers. The children had greater problems with balance than those in the other two severely underachieving groups but the effects were small. It is suggested that the use of a balance test only as a screener for dyslexia could result in a proportion of dyslexics being missed and that remedial motor training programmes for children with dyslexia should be offered only to those with co‐occurring motor difficulties. Copyright © 2007 John Wiley & Sons, Ltd.
Criteria for evaluating interventions
Authors: Miles T. R.
Published: October 2007

By common consent there is a ‘gold standard’ in reference to which the efficacy of medical interventions needs to be evaluated. It is suggested in this paper that in educational research achievement of this gold standard is rarely possible. It does not follow, however, that research that falls short of this standard is therefore valueless; there may be many different kinds of good (and less good) reasons for accepting particular conclusions. Copyright © 2007 John Wiley & Sons, Ltd.
H5EPTPACH2OH: Synthesis, Relaxometric Characterization and 1H NMR Spectroscopic Studies on the Solution Dynamics of Its LnIII Complexes
Authors: Torres Susana , Martins José A. , André João P. , Pereira Giovannia A. , Kiraly Robert , Brücher Ernö , Helm Lothar , Tóth Éva , Geraldes Carlos F. G. C.
Published: October 2007

The synthesis and characterization of a new metal chelator, 4‐(S)‐hydroxymethyl‐3,6,10‐tri(carboxymethyl)‐3,6,10‐triazadodecanedioic acid (H5EPTPACH2OH), is reported. Protonation constants for the ligand H5EPTPACH2OH and for the previously reported H5EPTPAC16 have been determined by potentiometry, which reveals that both ligands display slightly higher protonation constants relative to that of the ligand DTPA5–. The stability constant for the [Gd(EPTPACH2OH)(H2O)]2– complex has also been determined by potentiometry. The obtained value (log KGdL = 16.7) is two orders of magnitude lower than that for the [Gd(EPTPA)(H2O)]2– complex, which indicates the destabilizing effect of the pendant hydroxymethyl group at the EPTPA backbone. The microscopic protonation scheme has been deduced from the pH dependence of the 1H NMR spectra of both H5EPTPACH2OH and H5EPTPAC16 ligands. The first two protonations occur exclusively at the backbone nitrogen atoms – the first protonation occurs preferentially at the more basic central nitrogen atom. The second proton distributes preferentially between the two terminal nitrogen atoms with the favoring of the trimethylene nitrogen atom over the ethylene nitrogen atom. The LnIII complexes of the ligand H5EPTPACH2OH have been prepared and their solution dynamics studied by 1H NMR spectroscopy. Two sets of resonances of very different intensities from two isomeric complexes have been observed. Relaxometric investigations (17O NMR and 1H NMRD) demonstrate that the [Gd(EPTPACH2OH)(H2O)]2– complex displays an accelerated water‐exchange rate (kex = 87.6 × 106 s–1) that is close to the theoretically derived optimal value. However, the kinetic stability of this complex in phosphate‐buffered solutions towards Zn2+ transmetallation is quite low, but higher than that of the corresponding methyl derivative.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Ruthenium‐Based NHC‐Arene Systems as Ring‐Opening Metathesis Polymerisation Catalysts
Authors: Ledoux Nele , Allaert Bart , Verpoort Francis
Published: October 2007

The availability of starting materials, the complexity of the preparative routes and the cost to make the catalyst are key in the development of industrially relevant olefin metathesis catalysts. With this in mind, new synthetic routes, which lead to alternatives for the classic ruthenium benzylidene complexes and circumvent the need for patented Grubbs intermediates were explored. The research presented herein focuses on the coordination of “saturated” N‐heterocyclic carbene (NHC) ligands to Ru dimer [(p‐cymene)RuCl2]2. As the coordination of the standard NHC ligand H2IMes (1,3‐dimesityl‐4,5‐dihydroimidazol‐2‐ylidene) was found to be unattainable, bidentate NHC analogues were synthesized instead. These are O‐hydroxyaryl‐substituted NHCs, capable of binding with the metal centre through the oxygen atom as well as through the carbene carbon atom. Their chelating properties improved the stability of the corresponding ruthenium arene complexes, which allowed more successful isolation. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Domino Transformations of gem‐Trifluoroacetyl(bromo)alkenes under the Action of Secondary Amines
Authors: Rulev Alexander Yu. , Uchakov Igor A. , Nenajdenko Valentin G. , Balenkova Elisabeth S. , Voronkov Mikhail G.
Published: October 2007

2‐Bromo‐3‐arylpropenyl trifluoromethyl ketones underwent aza‐Michael/hydroxyalkylation domino reactions triggered by secondary amines to give unexpectedly 2‐amino‐1‐trifluoromethyl indenols in good yields. The process was found to involve the intermediate formation of captodative aminoalkenes. Treatment of 2‐bromo‐3‐thienyl derivatives with the same nucleophiles afforded the captodative trifluoroacetyl(amino)alkenes. The indenols obtained in this reaction can be converted into the corresponding indanones by acid hydrolysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Highly Selective Preparation of a Chiral Quaternary Allyl Aryl Piperidinedione by Palladium‐Catalyzed Asymmetric Allylation Under Solid–Liquid Phase‐Transfer Catalysis
Authors: Nowicki Audrey , Keldenich Jérôme , Agbossou‐Niedercorn Francine
Published: October 2007

The combination of a chiral palladium catalyst and a solid–liquid phase‐transfer catalyst provides an effective method for the chemo‐ and enantioselective preparation of the chiral quaternary center of an allyl aryl piperidinedione. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Bismuth Triflate Catalyzed Allylation of Aldehydes with Allylstannane under Microwave Assistance
Authors: Ollevier Thierry , Li Zhiya
Published: October 2007

In the presence of a catalytic amount of bismuth triflate and under microwave irradiation, mixtures of aldehyde and allylstannane afforded smoothly the corresponding homoallylic alcohol. A wide variety of aldehydes were treated under these conditions. The reactions proceeded rapidly and afforded smoothly the corresponding homoallylic alcohol in good to very good yields using catalytic amounts of Bi(OTf)3·4H2O (0.5 mol‐%) and under microwave irradiation for a short time.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Probabilistic seismic hazard analysis: Early history
Authors: McGuire Robin K.
Published: October 2007

Probabilistic seismic hazard analysis (PSHA) is the evaluation of annual frequencies of exceedence of ground motion levels (typically designated by peak ground acceleration or by spectral accelerations) at a site. The result of a PSHA is a seismic hazard curve (annual frequency of exceedence vs ground motion amplitude) or a uniform hazard spectrum (spectral amplitude vs structural period, for a fixed annual frequency of exceedence). Analyses of this type were first conceived in the 1960s and have become the basis for the seismic design of engineered facilities ranging from common buildings designed according to building codes to critical facilities such as nuclear power plants. This Historical Note traces the early history of PSHA. Copyright © 2007 John Wiley & Sons, Ltd.
Reliability modelling of uninterruptible power supply systems using fault tree analysis method
Authors: Rahmat Mohd. Khairil , Jovanovic Slobodan
Published: October 2007

The aim of this paper is to investigate the reliability parameters estimation method for the uninterruptible power supply (UPS) systems using the fault tree analysis (FTA) technique. FTA is a top‐down approach to identify all potential causes leading to system failure. The computation of the system's failure probability is the main goal of this analysis, as this value can be used to calculate other important system reliability parameters such as failure rates, mean time between failures (MTBFs) and reliability. In this paper, the FTA method was applied to five different UPS topologies and the results obtained were compared and discussed in detail. By comparing the critical fault path of the system, it was found that the inverter failures contributed most significantly to the system failure. It was also found that the probability of failure of a UPS system can be reduced by the inclusion of bypass supply, given that the failure rate of the events that causing the failure of the bypass supply should be lower compared to the main utility supply. Finally, to validate the results obtained from this method, comparisons were made to the results from other methods such as the reliability block diagram (RBD), Boolean Truth Table, probability tree, Monte‐Carlo simulation and field data reliability estimation methods. Copyright © 2007 John Wiley & Sons, Ltd.
A fuzzy logic based approach to determine system well‐being indices
Authors: Fotuhi‐Firuzabad Mahmud , Abiri‐Jahromi Amir
Published: October 2007

A new approach is presented in this paper to determine the degree of system well‐being in the form of healthy, marginal and at risk state indices using the fuzzy logic concepts. Conventional well‐being method uses a crisp deterministic criterion to divide power system comfort zone into the healthy and marginal states. In this regard, the main drawback is associated with categorising the system performance in the comfort zone into the healthy and marginal states. To overcome this problem, a new approach is developed that categorises the states as healthy or marginal using fuzzy logic. The technique together with the effects on the system risk and the system health and margin probabilities of factors such as lead time, system peak load variation and load forecast uncertainty are illustrated by application to the IEEE‐RTS. Copyright © 2007 John Wiley & Sons, Ltd.
Changes in neural activity associated with learning to articulate novel auditory pseudowords by covert repetition
Authors: Rauschecker Andreas M. , Pringle Abbie , Watkins Kate E.
Published: October 2007

Learning to articulate novel combinations of phonemes that form new words through a small number of auditory exposures is crucial for development of language and our capacity for fluent speech, yet the underlying neural mechanisms are largely unknown. We used functional magnetic resonance imaging to reveal repetition–suppression effects accompanying such learning and reflecting discrete changes in brain activity due to stimulus‐specific fine‐tuning of neural representations. In an event‐related design, subjects were repeatedly exposed to auditory pseudowords, which they covertly repeated. Covert responses during scanning and postscanning overt responses showed evidence of learning. An extensive set of regions activated bilaterally when listening to and covertly repeating novel pseudoword stimuli. Activity decreased, with repeated exposures, in a subset of these areas mostly in the left hemisphere, including premotor cortex, supplementary motor area, inferior frontal gyrus, superior temporal cortex, and cerebellum. The changes most likely reflect more efficient representation of the articulation patterns of these novel words in two connected systems, one involved in the perception of pseudoword stimuli (in the left superior temporal cortex) and one for processing the output of speech (in the left frontal cortex). Both of these systems contribute to vocal learning. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
Spatial nonuniformity of the resting CBF and BOLD responses to sevoflurane: In vivo study of normal human subjects with magnetic resonance imaging
Authors: Qiu Maolin , Ramani Ramachandran , Swetye Michael , Constable Robert Todd
Published: October 2007

Pulsed arterial spin labeling magnetic resonance imaging (MRI) was performed to investigate the local coupling between resting regional cerebral blood flow (rCBF) and BOLD (blood oxygen level dependent) signal changes in 22 normal human subjects during the administration of 0.25 MAC (minimum alveolar concentration) sevoflurane. Two states were compared with subjects at rest: anesthesia and no‐anesthesia. Regions of both significantly increased and decreased resting‐state rCBF were observed. Increases were limited primarily to subcortical structures and insula, whereas, decreases were observed primarily in neocortical regions. No significant change was found in global CBF (gCBF). By simultaneously measuring rCBF and BOLD, region‐specific anesthetic effects on the coupling between rCBF and BOLD were identified. Multiple comparisons of the agent‐induced rCBF and BOLD changes demonstrated significant (P < 0.05) spatial variability in rCBF–BOLD coupling. The slope of the linear regression line for AC, where rCBF was increased by sevoflurane, was markedly smaller than the slope for those ROIs where rCBF was decreased by sevoflurane, indicating a bigger change in BOLD per unit change in rCBF in regions where rCBF was increased by sevoflurane. These results suggest that it would be inaccurate to use a global quantitative model to describe coupling across all brain regions and in all anesthesia conditions. The observed spatial nonuniformity of rCBF and BOLD signal changes suggests that any interpretation of BOLD fMRI data in the presence of an anesthetic requires consideration of these insights. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
ATP8B1 requires an accessory protein for endoplasmic reticulum exit and plasma membrane lipid flippase activity
Authors: Paulusma Coen C. , Folmer Dineke E. , Ho-Mok Kam S. , de Waart Rudi D. , Hilarius Petra M. , Verhoeven Arthur J. , Oude Elferink Ronald P. J.
Published: October 2007

Mutations in ATP8B1 cause progressive familial intrahepatic cholestasis type 1 and benign recurrent intrahepatic cholestasis type 1. Previously, we have shown in mice that Atp8b1 deficiency leads to enhanced biliary excretion of phosphatidylserine, and we hypothesized that ATP8B1 is a flippase for phosphatidylserine. However, direct evidence for this function is still lacking. In

Saccharomyces cerevisiae

, members of the Cdc50p/Lem3p family are essential for proper function of the ATP8B1 homologs. We have studied the role of two human members of this family, CDC50A and CDC50B, in the routing and activity of ATP8B1. When only ATP8B1 was expressed in Chinese hamster ovary cells, the protein localized to the endoplasmic reticulum. Coexpression with CDC50 proteins resulted in relocalization of ATP8B1 from the endoplasmic reticulum to the plasma membrane. Only when ATP8B1 was coexpressed with CDC50 proteins was a 250%-500% increase in the translocation of fluorescently labeled phosphatidylserine observed. Importantly, natural phosphatidylserine exposure in the outer leaflet of the plasma membrane was reduced by 17%-25% in cells coexpressing ATP8B1 and CDC50 proteins in comparison with cells expressing ATP8B1 alone. The coexpression of ATP8B1 and CDC50A in WIF-B9 cells resulted in colocalization of both proteins in the canalicular membrane.

Conclusion:

Our data indicate that CDC50 proteins are pivotal factors in the trafficking of ATP8B1 to the plasma membrane and thus may be essential determinants of ATP8B1-related disease. In the plasma membrane, ATP8B1 functions as a flippase for phosphatidylserine. Finally, CDC50A may be the potential β-subunit or chaperone for ATP8B1 in hepatocytes. (Hepatology 2007.)
Algorithms for uncertainty propagation in transmission‐line matrix (TLM) method
Authors: Borges G. A. , Júnior E. A. C. , de Menezes L. R. A. X.
Published: October 2007

This paper presents new techniques coupling uncertainty propagation with the transmission‐line matrix method. This improves the quality of electromagnetic simulation. The reason is that in this case the solution provides not only the average field value but also the associated covariances. This is very useful when incomplete or uncertain information is inherent to the problem. The technique is much faster than regular Monte Carlo simulations, which are used in other methods. Copyright © 2007 John Wiley & Sons, Ltd.
CEO values, organizational culture and firm outcomes
Authors: Berson Yair , Oreg Shaul , Dvir Taly
Published: October 2007

Few empirical works have examined the process through which CEO dispositions relate to organizational outcomes. In this study we examined the relationships between CEO values and organizational culture, and between organizational culture and firm performance. Data were collected from different sources (26 CEOs, 71 Senior Vice Presidents and 185 other organizational members), and include organizational financial performance data collected at two points in time. In support of our hypotheses, CEO self‐directive values were associated with innovation‐oriented cultures, security values were associated with bureaucratic cultures and benevolence values were related to supportive cultures. In turn, cultural dimensions showed differential associations with subsequent company sales growth, an index of organizational efficiency and assessments of employee satisfaction. Copyright © 2007 John Wiley & Sons, Ltd.
Characterisation of Taiwanese propolis collected from different locations and seasons
Authors: Chen Yue‐Wen , Wu Shiao‐Wen , Ho Kai‐Kuang , Lin Shih‐Bin , Huang Chung‐Yang , Chen Chia‐Nan
Published: October 2007

BACKGROUND: Characterisation of propolis is difficult because of the fact that its chemical composition can vary with its source of origin. The aim of this study was to establish distinctive criteria relating to quantifiable quality features of Taiwanese propolis (TP). Thirty‐four samples of TP were collected from nine different locations in different seasons. Based on colour, the 34 samples were categorised into three groups, TW‐I (green), TW‐II (brownish green) and TW‐III (dark brown). Ethanolic extracts of these samples were tested for dry extract yield, total phenolic content, propolin content, antiradical activity and antimicrobial activities.

RESULTS: TW‐I had a higher dry extract yield (71.5 ± 6.0%), a higher total phenolic content and higher propolin levels than TW‐II and TW‐III. It also showed a stronger ability to scavenge 1,2‐diphenyl‐2‐picryhydrazyl (DPPH) free radicals. Both TW‐I and TW‐II had higher antimicrobial activities than TW‐III.

CONCLUSION: The results indicated that the high biological activities of TW‐I might be correlated with its high content of propolins. In summary, propolin content, colour and season might be useful as quality parameters of TP. Copyright © 2007 Society of Chemical Industry
Shelf‐life prediction of edible fats and oils using Rancimat
Authors: Farhoosh Reza
Published: October 2007

Determining the shelf‐life of edible fats and oils under normal storage conditions is a tedious and time‐consuming task. Accelerated tests are therefore frequently used to determine the stability of the products at ambient conditions. However, the mechanisms of lipid oxidation at accelerated conditions may be different from those under normal storage conditions, leading to errors in the shelf‐life predictions. This article describes an automated accelerated method, namely Rancimat, for shelf‐life prediction of edible fats and oils under normal storage conditions, and the effect of its operational parameters on these predictions.
Oleoyl‐ethanolamide (OEA): A bioactive lipid derived from oleic acid and phosphatidylethanol‐amine
Authors: Thabuis Clémentine , Destaillats Frédéric , Tissot‐Favre Delphine , Martin Jean‐Charles
Published: October 2007

Fatty acid ethanolamides are lipid compounds with biological activities. Among them, oleoyl‐ethanolamide (OEA) has attracted a great deal of interest because of its biological properties. OEA is found in low amount in foodstuffs, but mainly stems from endogenous synthesis. In rodents, intraperitoneal administration of OEA induces satiety and peripheral utilization of lipid substrate. Both in vitro studies and knock‐out animal models have revealed some mechanisms of action, such as PPARα signaling, selected neuron activation and endocrine (ghrelin) signaling. The proximal intestine seems to be a target organ for satiety control. Acute oral administration also induces satiety. Further studies are still required to better address the physiological impact of both oral and intraperitoneal OEA when administrated in the long term.
Polymers for in vivo Tuning of Refractive Properties in Intraocular Lenses
Authors: Träger Jens , Heinzer Jasmin , Kim Hee‐Cheol , Hampp Norbert
Published: October 2007

High‐refractive‐index polymers for intraocular lenses are presented whose refractive index can be tuned post‐operatively in a non‐invasive manner to enable focal length and aspheric corrections in vivo. The polymer materials contain covalently attached photochemically crosslinkable coumarin side groups, to cause a change in refractive index of Δn > 0.02, which enables one to tune the focal length of a standard IOL by two diopters. This is enough to ensure that more than 80% of all cataract patients can be adjusted non‐invasively to optimal vision after cataract surgery, thus providing a remedy to a major shortcoming of today's cataract surgery.

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Thermal and Morphological Behaviour of Well‐Defined Amphiphilic Triblock Copolymers Based on Cyclohexyl and Di(ethylene glycol) Methyl Ether Methacrylates
Authors: Muñoz‐Bonilla Alexandra , Haddleton David M. , Cerrada Maria L. , Fernández‐García Marta
Published: October 2007

The microphase separation and morphology of PDEG‐b‐PCH‐b‐PDEG and PCH‐b‐PDEG‐b‐PCH amphiphilic triblock copolymers have been studied by DSC, SAXS and AFM. A clear first‐order scattering peak was observed for most of the triblock copolymers, independent of the macroinitiator used. This diffraction has been ascribed to the development of a lamellar structure, which was confirmed by AFM. On the other hand, the existence of an ODT upon heating was observed for most of the triblock copolymers. The ODT location was dependent on the outer segment molecular weights, shifting at higher temperatures as the polymerisation degree increased. WAXS profiles were checked to determine the glass transition and ODT temperatures.

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Synthesis, Phase Behaviour and Mechanical Properties of Poly(2‐methyl‐1,3‐propanediol‐4,4′‐bibenzoate)
Authors: Fernández‐Blázquez Juan P. , Bello Antonio , Pérez Ernesto
Published: October 2007

The synthesis and phase behaviour of PB32 is reported. The results indicate that PB32 develops a low‐ordered smectic mesophase of the type SmCalt. The slow formation of such a mesophase allows the quenching of the isotropic melt into an amorphous state so that both amorphous glass and smectic glass can be obtained, which exhibit different glass‐transition temperatures. Mechanical tests indicate that the macromolecular chains in the mesophase of PB32 can be oriented either parallel or perpendicularly in relation to the streching direction, depending on the deformation conditions. Solid‐state 13C NMR spectroscopy results show that the mobility of the chains is rather similar in both phases.

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Atom Transfer Radical Polymerization of iso‐Butyl Methacrylate in Microemulsion with Cationic and Non‐Ionic Emulsifiers
Authors: Kagawa Yasuyuki , Kawasaki Masahiro , Zetterlund Per B. , Minami Hideto , Okubo Masayoshi
Published: October 2007

Direct atom transfer radical polymerization (ATRP) of iso‐butyl methacrylate in microemulsion has been performed successfully for the first time. ATRP was performed at 40 °C with different emulsifier systems: i) the cationic emulsifier n‐tetradecyltrimethylammonium bromide (TTAB); and ii) mixed emulsifier systems based on TTAB and the non‐ionic emulsifiers Emulgen 911 or Emulgen 931. All polymerizations proceeded in a controlled/living fashion, and the microemulsions were transparent with particle diameters less than 15 nm. The emulsifier system TTAB/Emulgen 911 exhibited better control than TTAB only. This is proposed to be caused by complex formation between Emulgen 911 in the organic phase and CuBr2 (the deactivator), thus reducing the extent of exit of CuBr2 to the aqueous phase. The more hydrophilic Emulgen 931 did not lead to improved control.

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Macromol. Theory Simul. 8/2007
Authors: van den Noort A. , Briels W. J.
Published: October 2007

Cover: Polymers in the shells of two resin particles, stationary at a close distance, relax to an entangled equilibrium state. When the particles next move to a larger distance the entangled polymers give rise to transient attractive forces. These forces have no influence on the static properties of the system, but to a large extent determine its rheological properties. Further details can be found in the article by A. van den Noort* and W. J. Briels on page 742.
Effective use of a Strategic Issue Management System (SIMS): combining tools and approach
Authors: Oliver G. R. , Donnelly P. J.
Published: October 2007

Ideally, issue management can prevent an issue from becoming an actual threat. But in reality, a company or group should be prepared to face issues that threaten a change in their status quo. This paper discusses the authors' experiences with blending the right tools with the right approach to successfully address issues that are imminent.

If the proper balance between process, interpretation and creativity is maintained, Strategic Issue Management Systems (SIMS) with their component tools can be used effectively to provide a more objective understanding of the issue and to shape a more effective strategic objective and tactical plan.

Key components of the SIMS presented include: issue characterization, strategic objectives, force field analysis, stakeholder assessment, scenario mapping, key player assessment and SWOT Analysis. Each can be used independently, but this paper focuses on how, when used in combination, each can build upon the other and produce an obtainable strategic objective and targeted tactical plan.

Although each component of the SIMS represents a stage in a process, the emphasis of the issue team should not be on completion of the process, but instead on what is learned from each stage and how the stages can then lead to a successful resolution of the issue.

Copyright © 2007 John Wiley & Sons, Ltd.
Risk‐adjusted monitoring of veno‐occlusive disease following Bayesian individualization of busulfan dosage for bone marrow transplantation in paediatrics
Authors: Kitio Brice , Bertholle Valerie , Galambrun Claire , Mialou Valerie , Bertrand Yves , Aulagner Gilles , Bleyzac Nathalie
Published: October 2007

In order to assess the performance of Bayesian individualization of busulfan (BU) dosage regimens, veno‐occlusive disease (VOD) rate was monitored for paediatric patients undergoing allogeneic bone marrow transplantation (BMT). Consecutive patients undergoing allogeneic BMT with BU as conditioning regimen during 5‐years period (January 2000–February 2006) were reviewed. VOD was a major outcome variable. Preconditioning risk of VOD was estimated for each patient using a scoring system that included type of transplant, recipient CMV‐positive status and total parenteral nutrition (TPN) provided pretransplantation. A risk‐adjusted cumulative sum method was used to compare observed versus predicted outcome by assigning a risk score, based on log‐likelihood ratios, to each patient. These cumulative scores were sequentially plotted with preset control limits for ‘signalling’ where results were substantially different than expected (doubling or halving of odds ratio). Sixty‐six children received BMT after oral busulfan‐based conditioning regimen with median age 3.9 years, 63.6% of male. Median preconditioning risk of VOD was 0.34 ranging from 0.23 to 0.84. Observed VOD rate was 16.7% (n = 11) which was 60.7% (17) fewer than the expected number estimated by the risk score. The resulting risk‐adjusted score for each patient was plotted sequentially. This plot adopted early a negative slope, crossing the lower control limit twice, after 27 and 66 patients, indicating improved results compared to those expected. Bayesian individualization of oral busulfan dosage regimens is useful to reduce the VOD rate in children undergoing allogeneic BMT. Copyright © 2007 John Wiley & Sons, Ltd.
A new strategy to filter out false positive identifications of peptides in SEQUEST database search results
Authors: Zhang Jiyang , Li Jianqi , Xie Hongwei , Zhu Yunping , He Fuchu
Published: October 2007

Based on the randomized database method and a linear discriminant function (LDF) model, a new strategy to filter out false positive matches in SEQUEST database search results is proposed. Given an experiment MS/MS dataset and a protein sequence database, a randomized database is constructed and merged with the original database. Then, all MS/MS spectra are searched against the combined database. For each expected false positive rate (FPR), LDFs are constructed for different charge states and used to filter out the false positive matches from the normal database. In order to investigate the error of FPR estimation, the new strategy was applied to a reference dataset. As a result, the estimated FPR was very close to the actual FPR. While applied to a human K562 cell line dataset, which is a complicated dataset from real sample, more matches could be confirmed than the traditional cutoff‐based methods at the same estimated FPR. Also, though most of the results confirmed by the LDF model were consistent with those of PeptideProphet, the LDF model could still provide complementary information. These results indicate that the new method can reliably control the FPR of peptide identifications and is more sensitive than traditional cutoff‐based methods.
Proteomic patterns for classification of ovarian cancer and CTCL serum samples utilizing peak pairs indicative of post‐translational modifications
Authors: Liu Chenwei , Shea Nancy , Rucker Sally , Harvey Linda , Russo Paul , Saul Richard , Lopez Mary F. , Mikulskis Alvydas , Kuzdzal Scott , Golenko Eva , Fishman David , Vonderheid Eric , Booher Susan , Cowen Edward W. , Hwang Sam T. , Whiteley Gordon R.
Published: October 2007

Proteomic patterns as a potential diagnostic technology has been well established for several cancer conditions and other diseases. The use of machine learning techniques such as decision trees, neural networks, genetic algorithms, and other methods has been the basis for pattern determination. Cancer is known to involve signaling pathways that are regulated through PTM of proteins. These modifications are also detectable with high confidence using high‐resolution MS. We generated data using a prOTOF™ mass spectrometer on two sets of patient samples: ovarian cancer and cutaneous t‐cell lymphoma (CTCL) with matched normal samples for each disease. Using the knowledge of mass shifts caused by common modifications, we built models using peak pairs and compared this to a conventional technique using individual peaks. The results for each disease showed that a small number of peak pairs gave classification equal to or better than the conventional technique that used multiple individual peaks. This simple peak picking technique could be used to guide identification of important peak pairs involved in the disease process.
Dominant negative Rac1 attenuates paclitaxel‐induced apoptosis in human melanoma cells through upregulation of heat shock protein 27: A functional proteomic analysis
Authors: Lee Shao Chin , Sim Nigel , Clement Marie‐Veronique , Yadav Sanjiv Kumar , Pervaiz Shazib
Published: October 2007

GTPase ras‐related C3 botulinum toxin substrate 1 (Rac1) plays a role in various cellular processes pertinent to cancer development. In the present study, we investigated the molecular mechanisms underlying apoptosis regulation by Rac1 through functional proteomic analysis of three human melanoma M14 cell lines stably transfected with constitutively active Rac1V12, dominant negative Rac1N17, and empty vector (pIRES), respectively. We found that paclitaxel evoked apoptosis in the melanoma cell lines through the intrinsic (mitochondria) pathway in a caspsae‐3‐dependent manner. Compared to the Rac1pIRES and Rac1V12 cells, Rac1N17 cells were more resistant to paclitaxel‐triggered caspase‐3 activation and apoptosis. Protein composition comparisons amongst the three cell lines identified two peptide spots of interest. One was Hsp27, which was upregulated in Rac1N17 cells as assessed in our gel image interpretation, PMF and Western blot analysis. The other was identified as SR‐25 protein (also known as the ADP‐ribosylation factor‐like factor 6‐interacting protein 4; ARL6IP4) using PMF, which was separated only from the Rac1N17 cells under the experimental conditions. Moreover, knockdown of the protein level of Hsp27 using small interfering RNA in Rac1N17 cells significantly increased the paclitaxel‐elicited caspase‐3 activation and apoptosis. In conclusion, our results implicate that Hsp27 and SR‐25 are mediators in Rac1 signaling pathway(s). It appears that the dominant negative Rac1N17 reduces the apoptosis sensitivity toward paclitaxel in the melanoma cells through upregulation of Hsp27, which inhibits its down stream drug‐elicited caspase‐3 activation.
Synthesis and morphological characterization of miktoarm star copolymers (PCL)2(PS)2of poly(ε‐caprolactone) and polystyrene
Authors: Lorenzo Arnaldo T. , Müller Alejandro J. , Priftis Dimitrios , Pitsikalis Marinos , Hadjichristidis Nikos
Published: October 2007

An heterofunctional initiator combining two reactive sites for ring opening polymerization and two for atom transfer radical polymerization was used to prepare three A2B2miktoarm star copolymers of poly(ε‐caprolactone) (PCL) and polystyrene (PS). The morphology and thermal properties were studied by transmission electron microscopy, polarized light optical microscopy, and differential scanning calorimetry. The (PCL)2(PS)272/28 (72 wt % PCL) sample was crystallized from a disordered melt. In this case, crystallization drove the structure formation and a lamellar morphology was obtained at the microdomain level, while spherulites were observed at a superstructural level. The other two samples, 39/61 and 27/73, with lower PCL content and higher total molecular weight, were not able to form spherulites. Surprisingly, these miktoarm star copolymers exhibited hexagonally packed cylinders and spheres morphologies, respectively, instead of lamellar and cylindrical morphology. Such unexpected and novel behavior was explained in terms of the higher resistance of the arms to be stretched in a miktoarm star copolymer when compared with the corresponding linear diblocks. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5387–5397, 2007
Synthesis and characterization of block copolymers containing poly(di(ethylene glycol) 2‐ethylhexyl ether acrylate) by reversible addition–fragmentation chain transfer polymerization
Authors: Venkataraman Shrinivas , Wooley Karen L.
Published: October 2007

Reversible addition–fragmentation chain transfer (RAFT) polymerization has emerged as one of the important living radical polymerization techniques. Herein, we report the polymerization of di(ethylene glycol) 2‐ethylhexyl ether acrylate (DEHEA), a commercially‐available monomer consisting of an amphiphilic side chain, via RAFT by using bis(2‐propionic acid) trithiocarbonate as the chain transfer agent (CTA) and AIBN as the radical initiator, at 70 °C. The kinetics of DEHEA polymerization was also evaluated. Synthesis of well‐defined ABA triblock copolymers consisting of poly(tert‐butyl acrylate) (PtBA) or poly(octadecyl acrylate) (PODA) middle blocks were prepared from a PDEHEA macroCTA. By starting from a PtBA macroCTA, a BAB triblock copolymer with PDEHEA as the middle block was also readily prepared. These amphiphilic block copolymers with PDEHEA segments bearing unique amphiphilic side chains could potentially be used as the precursor components for construction of self‐assembled nanostructures. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5420–5430, 2007
Helical polyacetylenes carrying 2,2,6,6‐tetramethyl‐1‐piperidinyloxy and 2,2,5,5‐tetramethyl‐1‐pyrrolidinyloxy moieties: Their synthesis, properties, and function
Authors: Qu Jinqing , Fujii Toru , Katsumata Toru , Suzuki Yuji , Shiotsuki Masashi , Sanda Fumio , Satoh Masaharu , Wada Jun , Masuda Toshio
Published: October 2007

2,2,6,6‐Tetramethyl‐1‐piperidinyloxy (TEMPO)‐ and 2,2,5,5‐tetramethyl‐1‐pyrrolidinyloxy (PROXYL)‐containing (R)‐1‐methylpropargyl TEMPO‐4‐carboxylate (1), (R)‐1‐methylpropargyl PROXYL‐3‐carboxylate (2), (rac)‐1‐methylpropargyl PROXYL‐3‐carboxylate (3), (S)‐1‐propargylcarbamoylethyl TEMPO‐4‐carboxylate (4), and (S)‐1‐propargyloxycarbonylethyl TEMPO‐4‐carboxylate (5) (TEMPO, PROXYL) were polymerized to afford novel polymers containing the TEMPO and PROXYL radicals at high densities. Monomers 1–3 and 5 provided polymers with moderate number‐average molecular weights of 8200–140,900 in 49–97% yields in the presence of (nbd)Rh+[η6‐C6H5B−(C6H5)3], whereas 4 gave no polymer with this catalyst but gave polymers possessing low Mn (3800–7500) in 56–61% yield with [(nbd)RhCl]2‐Et3N. Poly(1), poly(2), and poly(4) took a helical structure with predominantly one‐handed screw sense in THF and CHCl3 as well as in film state. The helical structure of poly(1) and poly(2) was stable upon heating and addition of MeOH, whereas poly(4) was responsive to heat and solvents. All of the free radical‐containing polymers displayed the reversible charge/discharge processes, whose capacities were in a range of 43.2–112 A h/kg. In particular, the capacities of poly(2)–poly(5)‐based cells reached about 90–100% of the theoretical values regardless of the secondary structure of the polymer, helix and random. Poly(1), poly(2), and poly(4) taking a helical structure exhibited better capacity tolerance towards the increase of current density than nonhelical poly(3) and poly(5) did. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5431–5445, 2007