bluuebunny/crossref_metadata_2025 huggingface dataset:
Polysaccharide‐Containing Block Copolymers: Synthesis, Properties and Applications of an Emerging Family of Glycoconjugates
Authors: Schatz Christophe , Lecommandoux Sébastien
Published: August 2010

While polysaccharide graft copolymers and glycopolymers have been widely studied and used in various applications, linear block copolymer structures combining a polysaccharide segment and a synthetic one have been less described. The limited availability of the polysaccharide reducing‐end, the difficulty of finding a common solvent of both blocks and the need sometimes to protect the lateral hydroxyl groups of the polysaccharide chain may explain the relatively low number of studies on this copolymer family despite its potential interest. Polysaccharide block copolymers feature physicochemical properties not only close to those of synthetic block copolymers but also bring an added value such as the biodegradability, the biocompatibility or the bioactivity in some cases. This review aims at presenting the synthetic pathways towards such structures, from the basic polymerization techniques to the most recent ones including controlled/living polymerization mechanisms and also by emphasizing the chemical reactions used to functionalize the reducing‐end of the polysaccharide block. The amphiphilic nature of most of the polysaccharide‐based block copolymers reported so far gives rise to various self‐assembly morphologies in the solid state or in selective solvents. In addition, the rigidity of the polysaccharide block is expected to influence the microphase separation of the block copolymer by increasing the thermodynamic incompatibility between dissimilar blocks. A special interest was drawn to the formation and the properties of polymer vesicles (polymersomes) in aqueous solutions. Polysaccharide block copolymers might represent a new class of biomaterials with potential applications in different fields such as the plastic industry, the detergency and also the pharmaceutics where the design of nanodevices carrying a native polysaccharide chain is of interest for therapy, vaccination and diagnosis purposes.

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On the Scaling Behavior of the Force/Extension Relation of a Chain
Authors: Kosmas Marios K.
Published: August 2010

Applying an extending force F along the end‐to‐end vector r of a chain enlarges the initial size ρi ∼ |ri| leading to a final state with ρf larger than ρi. Assuming a power law dependence of the size ρ ∼ Nν of the chain on its length N, at the two different states with different exponents νi and νf, a scaling relationship is derived between the measure of the extending force F and the extension ρ of the chain. The exponent γ of the force/extension relation, ρ ∼ Fγ, depends on both exponents νi and νf of the initial and the final states. A relation between γ and the exponents νi and νf is derived which permits the explanation of previous results and predicts some more. The scaling behavior is checked with the exactly soluble model of a random walk under a force.

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The Computerised Manchester Child Attachment Story Task: a novel medium for assessing attachment patterns
Authors: Minnis Helen , Read Warren , Connolly Brenda , Burston Amanda , Schumm Tanja‐Sabine , Putter‐Lareman Suren , Green Jonathan
Published: August 2010

The Manchester Child Attachment Story Task (MCAST) is a representational technique for assessing attachment patterns of young school‐age children. We have developed a computerised version (the CMCAST) in which story stems are represented on the computer by the movement of simple screen ‘dolls’.

This paper reports on a preliminary validation study of the CMCAST method against the MCAST.

Fifty‐five children completed the MCAST and CMCAST six weeks apart in random order. It proved possible to rate the CMCAST if a simplified form of the MCAST coding system was used. Inter‐rater reliability was achieved for both versions (kappa = 0.93 for MCAST and kappa = 0.91 for CMCAST). Agreement between the MCAST and CMCAST ratings of attachment security was kappa = 0.67. Costs for the MCAST and CMCAST were comparable.

A school‐based feasibility study of 86 children suggested that the CMCAST was acceptable and could be administered with up to five children simultaneously.

This preliminary study suggests that the CMCAST can reliably reproduce a simplified form of MCAST coding. The computer format may be well adapted to some uses such as screening for large‐scale epidemiological research. Copyright © 2010 John Wiley & Sons, Ltd.
Indirect detection of the 183W and 57Fe nuclei using 119Sn‐relayed 1H,X correlation spectroscopy
Authors: Mobley T. Andrew , Tennyson Eleanor G. , Hisao Grant S.
Published: August 2010

Recently reported triple‐resonance Y‐relayed 1H,X correlation experiments have been utilized to characterize 183W and 57Fe chemical shifts using 119Sn as the Y‐relaying nucleus instead of the previously used 31P. Application of an adaptation of Gudat's original INEPT/HMQC sequence results in a significant enhancement of the signal‐to‐noise (S/N) ratio for two‐dimensional 119Sn‐relayed 1H,183W and 1H, 57Fe correlation spectra with efficient detection of the transition metal nucleus in tungsten and iron complexes lacking an observable direct scalar coupling between the transition metal and any hydrogen nuclei. Strengths and shortcomings of the novel sequence and the original sequences reported by Gudat are discussed in the context of 119Sn‐relayed proton detection of very low frequency transition metal nuclei. Copyright © 2010 John Wiley & Sons, Ltd.
Mechanism for the direct synthesis of tryptophan from indole and serine: a useful NMR technique for the detection of a reactive intermediate in the reaction mixture
Authors: Yokoyama Yuusaku , Nakakoshi Masamichi , Okuno Hiroaki , Sakamoto Yohko , Sakurai Satoshi
Published: August 2010

The reaction mechanism for the biomimetic synthesis of tryptophan from indole and serine in the presence of Ac2O in AcOH was investigated. Although the time‐course 1H‐NMR spectra of the reaction of 5‐methoxyindole with N‐acetylserine were measured in the presence of (CD3CO)2O in CD3CO2D, the reactive intermediate could not be detected. This reaction was conducted without 5‐methoxyindole in order to elucidate the reactive intermediate, but the intermediate could not be isolated from the reaction mixture. Since the intermediate would be expected to have a very short life time, and therefore be very difficult to detect by conventional analytical methods, the structure of the intermediate was elucidated using a 2D‐NMR technique, diffusion‐ordered spectroscopy (DOSY). Two intermediates were detected and confirmed to be 2‐methyl‐4‐methyleneoxazol‐5(4H)‐one and 2‐methyl‐4‐hydroxymethyloxazol‐5(4H)‐one. The present results demonstrated that DOSY is a powerful tool for the detection of unstable intermediates. Copyright © 2010 John Wiley & Sons, Ltd.
Self‐management strategies used during flares of rheumatoid arthritis in an ethnically diverse population
Authors: Kett Charlotte , Flint Julia , Openshaw Mark , Raza Karim , Kumar Kanta
Published: August 2010

Objectives. Effective management of flares of rheumatoid arthritis (RA) can improve symptoms and may delay disease progression. The practice of rheumatologists in managing a flare has been studied, but patients' experiences of, and responses to, disease flares remain poorly defined. This study aimed to address this issue.

Methods. Semi‐structured interviews were conducted with 21 patients from an ethnically diverse population who had suffered a recent RA flare. Open questions were asked regarding patients' definitions of a flare, causal attribution, self‐management strategies, their triggers to consult health professionals, and the information they had received about RA flares from health professionals. Transcripts were studied using the grounded theory approach to identify themes.

Results. Flares were usually described as worsening joint pain and swelling. Over‐use of joints was identified as the most common cause of a flare, and commonly used self‐management strategies included rest, gentle exercise and warming the joints. There was some variation in causal attribution and self‐management with ethnicity.

Conclusions. This study identified a link between causal attribution of flares and the resultant self‐management strategies. A perceived trigger of the flare in some patients formed a focus for their self‐management strategies, whereas those who could not identify a cause aimed mainly to alleviate symptoms. A better understanding of patients' perspective in the context of disease flares will allow the development of educational programmes to facilitate more effective self‐management of this important manifestation of disease. Copyright © 2010 John Wiley & Sons, Ltd.
Validation of the in vivo assessment of pyruvate dehydrogenase activity using hyperpolarised 13C MRS
Authors: Atherton Helen J. , Schroeder Marie A. , Dodd Michael S. , Heather Lisa C. , Carter Emma E. , Cochlin Lowri E. , Nagel Simon , Sibson Nicola R. , Radda George K. , Clarke Kieran , Tyler Damian J.
Published: August 2010

Many diseases of the heart are characterised by changes in substrate utilisation, which is regulated in part by the activity of the enzyme pyruvate dehydrogenase (PDH). Consequently, there is much interest in the in vivo evaluation of PDH activity in a range of physiological and pathological states to obtain information on the metabolic mechanisms of cardiac diseases. Hyperpolarised [1‐13C]pyruvate, detected using MRS, is a novel technique for the noninvasive evaluation of PDH flux. PDH flux has been assumed to directly reflect in vivo PDH activity, although to date this assumption remains unproven. Control animals and animals undergoing interventions known to modulate PDH activity, namely high fat feeding and dichloroacetate infusion, were used to investigate the relationship between in vivo hyperpolarised MRS measurements of PDH flux and ex vivo measurements of PDH enzyme activity (PDHa). Further, the plasma concentrations of pyruvate and other important metabolites were evaluated following pyruvate infusion to assess the metabolic consequences of pyruvate infusion during hyperpolarised MRS experiments. Hyperpolarised MRS measurements of PDH flux correlated significantly with ex vivo measurements of PDHa, confirming that PDH activity influences directly the in vivo flux of hyperpolarised pyruvate through cardiac PDH. The maximum plasma concentration of pyruvate reached during hyperpolarised MRS experiments was approximately 250 µM, equivalent to physiological pyruvate concentrations reached during exercise or with dietary interventions. The concentrations of other metabolites, including lactate, glucose and β‐hydroxybutyrate, did not vary during the 60 s following pyruvate infusion. Hence, during the 60‐s data acquisition period, metabolism was minimally affected by pyruvate infusion. Copyright © 2010 John Wiley & Sons, Ltd.
Real‐time MRI at a resolution of 20 ms
Authors: Uecker Martin , Zhang Shuo , Voit Dirk , Karaus Alexander , Merboldt Klaus‐Dietmar , Frahm Jens
Published: August 2010

The desire to visualize noninvasively physiological processes at high temporal resolution has been a driving force for the development of MRI since its inception in 1973. In this article, we describe a unique method for real‐time MRI that reduces image acquisition times to only 20 ms. Although approaching the ultimate limit of MRI technology, the method yields high image quality in terms of spatial resolution, signal‐to‐noise ratio and the absence of artifacts. As proposed previously, a fast low‐angle shot (FLASH) gradient‐echo MRI technique (which allows for rapid and continuous image acquisitions) is combined with a radial encoding scheme (which offers motion robustness and moderate tolerance to data undersampling) and, most importantly, an iterative image reconstruction by regularized nonlinear inversion (which exploits the advantages of parallel imaging with multiple receiver coils). In this article, the extension of regularization and filtering to the temporal domain exploits consistencies in successive data acquisitions and thereby enhances the degree of radial undersampling in a hitherto unexpected manner by one order of magnitude. The results obtained for turbulent flow, human speech production and human heart function demonstrate considerable potential for real‐time MRI studies of dynamic processes in a wide range of scientific and clinical settings. Copyright © 2010 John Wiley & Sons, Ltd.
FQL‐RED: an adaptive scalable schema for active queue management
Authors: Masoumzadeh Seyed Saeid , Meshgi Kourosh , Ghidari Saeid Shiry , Taghizadeh Gelareh
Published: August 2010

In a potentially congested network, random early detection (RED) active queue management (AQM) proved effective in improving throughput and average queuing delay. The main disadvantage of RED is its sensitive parameters that are impossible to estimate perfectly and adjust manually because of the dynamic nature of the network. For this reason, RED performs differently during different phases of a scenario and there is no guarantee that it will have optimal performance. Giving adaptability to RED has been the subject of broad research studies ever since RED was proposed. After a substantial study of AQM schemes and presenting a novel categorization for so‐called modern approaches utilizing artificial intelligence tools to improve AQM, this paper proposes an algorithm enhancing RED as an add‐on patch that makes minimal changes to the original RED. Being built on the basis of AQM schemes like ARED and Fuzzy‐RED, this algorithm inherits adaptability and is able to adjust RED inaccurate parameters regarding network traffic status, trying to optimize throughput and average queuing delay in a scenario. This algorithm is a Q‐learning method enhanced with a fuzzy inference system to provide RED with self‐adaptation and improved performance as a result. Given the name of FQL‐RED, this algorithm outperformed RED, ARED, and Fuzzy‐RED, as the OPNET simulations show. Copyright © 2010 John Wiley & Sons, Ltd.
Skeletal trauma in the burials from the royal church of St. Mary in medieval Oslo
Authors: Brødholt E. T. , Holck P.
Published: August 2010

The considerable collection of skeletal remains from the royal Church of St. Mary (c.1050–1540 AD) in Oslo constitutes part of The Schreiner Collection at the Department of Anatomy, University of Oslo. The remains reveal a high incidence of skeletal trauma, especially injuries caused by sharp‐edged weapons and extensive violence. Evidence of sharp force trauma was primarily observed on the crania. There were a surprisingly few injuries on postcranial skeletal elements. The injuries were mostly observed on middle‐aged and older men, but also on women and subadults. Some of these injuries may be linked to the civil wars in Norway during the 12th and 13th centuries. In most cases, the trauma distribution pattern suggests standardized fighting techniques. Copyright © 2010 John Wiley & Sons, Ltd.
Optimal start‐up of microfabricated power generation processes employing fuel cells
Authors: Chachuat B. , Mitsos A. , Barton P. I.
Published: August 2010

Microfabricated fuel cell systems have the potential to outperform batteries for man‐portable power generation. Because many electronic devices operate at various loads, with frequent start‐ups and shut‐downs, transient aspects are highly important and must be considered thoroughly. In this paper, the focus is on the optimal start‐up of microfabricated fuel cell systems using numerical open‐loop optimal control. For start‐up purposes, a small rechargeable battery is used to provide the energy needed to heat up the fuel cell stack and meet the power demand when the fuel cell is unavailable or can only satisfy part of the demand. The objective of the start‐up problem is to bring the system to a desired operating point with a minimal total mass of the system (battery and fuels), while meeting the nominal power demand at any time and satisfying the operational restrictions. The model for the fuel cell stack consists of partial differential‐algebraic equations with multiple time scales and numerical techniques that exploit a separation of these time scales are used for efficient and reliable integration of the state and sensitivity equations. A case study of a microfabricated power generation system employing a high‐temperature solid‐oxide fuel cell and using ammonia and butane as fuels is presented. Copyright © 2010 John Wiley & Sons, Ltd.
Environmental pollution, the public sector and economic growth: A comparison of different scenarios
Authors: Greiner Alfred
Published: August 2010

In this paper we present an endogenous growth model with productive public capital and environmental pollution. Emissions result from production and raise the stock of pollution that negatively affects the utility of the household. The government levies an income tax and a tax on emissions and uses its revenues for public investment and for abatement of pollution. This paper studies the structure of the model assuming three different scenarios and analyzes how the latter affects the balanced growth rate of the economy and welfare. The first scenario posits that abatement is set such that the stock of pollution is constant, in the second scenario pollution declines over time, and in the third scenario, pollution grows at the same positive rate as the economic variables. Copyright © 2010 John Wiley & Sons, Ltd.
Robust H∞ control of linear time‐varying systems with mixed delays in the Hilbert space
Authors: Bay Nguyen S. , Linh Nguyen M. , Phat Vu N.
Published: August 2010

In this paper, a class of linear infinite‐dimensional systems with discrete and distributed time‐varying delays is studied. New sufficient conditions for the robust H∞ control of linear time‐varying control systems with mixed time‐varying delays in Hilbert spaces have been established. The conditions are given in terms of the solution of a Riccati differential equation. Furthermore, it is proved for the first time that the solution to the robust H∞ control problem can be solved by the global controllability of an appropriate linear control delay‐like system. Copyright © 2010 John Wiley & Sons, Ltd.
A novel continuous genetic algorithm for the solution of optimal control problems
Authors: Abo‐Hammour Zaer S. , Asasfeh Ali Ghaleb , Al‐Smadi Adnan M. , Alsmadi Othman M. K.
Published: August 2010

In this paper, the Continuous Genetic Algorithm (CGA), previously developed by the principal author, is applied for the solution of optimal control problems. The optimal control problem is formulated as an optimization problem by the direct minimization of the performance index subject to constraints, and is then solved using CGA. In general, CGA uses smooth operators and avoids sharp jumps in the parameter values. This novel approach possesses two main advantages when compared to other existing direct and indirect methods that either suffer from low accuracy or lack of robustness. First, our method can be applied to optimal control problems without any limitation on the nature of the problem, the number of control signals, and the number of mesh points. Second, high accuracy can be achieved where the performance index is globally minimized while satisfying the constraints. The applicability and efficiency of the proposed novel algorithm for the solution of different optimal control problems is investigated. Copyright © 2010 John Wiley & Sons, Ltd.
Functionalization effect on physico‐mechanical properties of multi‐walled carbon nanotubes/epoxy composites
Authors: Wladyka‐Przybylak Maria , Wesolek Dorota , Gieparda Weronika , Boczkowska Anna , Ciecierska Ewelina
Published: August 2010

Functionalization of multi‐walled carbon nanotubes (MWCNTs) influences physico‐mechanical properties of MWCNT/epoxy composites. Samples based on epoxy resin (EP) and different weight percentage of MWCNTs (functionalized and non‐functionalized) were prepared. Epoxy/carbon nanotubes were prepared by different mixing methods (ultrasounds and a combination of ultrasounds and mechanical mixing) and better dispersion of carbon nanotubes (CNTs) was observed in the case of combination of these processes. CNTs modified with different functional groups were investigated. It was found that modified nanotubes form bigger agglomerates than unmodified ones. Surfactants were used to lower the surface tension of the liquid, which enabled easier spreading and reducing the interfacial tension. Some surfactants facilitate homogeneous dispersion of nanotubes in the resin through the reduction of resin viscosity.

Flammability of epoxy/MWCNTs composites was measured by cone calorimeter. The properties of epoxy/nanotubes composites strongly depend on homogeneous and uniform distribution of CNTs in the epoxy matrix. The microstructure of selected samples with the best CNTs homogeneity in the epoxy matrix was observed using atomic force microscope (AFM) and transmission electron microscope (TEM) techniques. The effect of mixing methods and parameters, as well as the amount and functionalization of CNTs, on mechanical properties (such as hardness, bending strength, tensile strength, and impact resistance) was evaluated. Copyright © 2010 John Wiley & Sons, Ltd.
Magnetically assisted removal and separation of cationic dyes from aqueous solution by magnetic nanocomposite hydrogels
Authors: Li Shengfang , Liu Xianli , Huang Weidong , Li Wen , Xia Xianyou , Yan Shilin , Yu Jianying
Published: August 2010

Magnetic poly(acrylic acid‐acrylamide‐butyl methacrylate) (P(AAB)) nanocomposite hydrogels were prepared and used as adsorbents for removal and separation of cationic dyes from aqueous solution. These magnetic P(AAB) nanocomposite hydrogels were characterized by scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM). It was found that these magnetic P(AAB) nanocomposite hydrogels had magnetic responsive characters. The dynamic swelling, removal, and separation of cationic dye, crystal violet (CV), and basic magenta (BM) by these magnetic nanocomposite hydrogels were studied. The adsorption capacity and isotherm studies of cationic dyes onto magnetic P(AAB) nanocomposite hydrogels have been evaluated. The magnetic P(AAB) nanocomposite hydrogels containing Fe3O4 particles can be easily manipulated in magnetic field for removal and separation of cationic dyes from aqueous solution. Adsorption process agreed very well with the Langmuir and Freundlich models. Copyright © 2010 John Wiley & Sons, Ltd.
Determination of hydroxylated fatty acids from the biopolymer of tomato cutin and their fate during incubation in soil
Authors: Hauff Simone , Chefetz Benny , Shechter Michal , Vetter Walter
Published: August 2010

Introduction – The plant cuticle is a thin, predominantly lipid layer that covers all primary aerial surfaces of vascular plants. The monomeric building blocks of the cutin biopolymer are mainly ω‐hydroxy fatty acids.

Objective – Analysis of ω‐hydroxy fatty acids from cutin isolated from tomato fruits at different stages of decomposition in soil. Different derivatives and mass spectrometric techniques were used for peak identification and evaluation.

Methodology – Preparation of purified cutin involving dewaxing and HCl treatment. Incubation of purified cutin for 20 months in soil. Pentafluorobenzoyl derivatives were used for GC/MS operated in the electron capture negative ion (ECNI) mode and trimethylsilyl ethers for GC/MS operated in the electron ionisation (EI) mode for analysis of ω‐hydroxy fatty acids.

Results – Six ω‐hydroxy fatty acids were detected in the purified cutin, three of which were identified as degradation products of 9,16‐dihydroxyhexadecanoic acid as a consequence of the HCl treatment involved in the purification step. Incubation of the isolated cutin in soil was accompanied with decrease in concentration of all hydroxyl fatty acids.

Conclusion – We produced evidence that the HCl treatment only affected free hydroxyl groups and thus could be used for proportioning free and bound OH‐groups on cutin fatty acids. The method enabled a direct quantification of the ω‐hydroxy fatty acids throughout the incubation phase. Copyright © 2010 John Wiley & Sons, Ltd.
Enantiomeric differentiation of atropine/hyoscyamine by 13C NMR spectroscopy and its application to Datura stramonium extract
Authors: Antoine Lanfranchi Don , Tomi Félix , Casanova Joseph
Published: August 2010

Introduction – The two enantiomers of hyoscyamine, an alkaloid found in many plant species, have distinct pharmacological and biological properties. Methods for the discrimination of both enantiomers are almost exclusively based on chiral HPLC/UV. Determination of the enantiomeric ratio (e.r.) of hyoscyamine is a challenging problem since this compound tends to racaemise, forming atropine during acid–base extraction.

Objective – To develop a protocol for the calculation of enantiomeric ratio of hyoscyamine in a plant extract using a 13C NMR method.

Methodology – Samples were prepared by extraction of dried Datura stramonium seeds. Observation of C12 and C15 NMR signals of hyoscyamine in the presence of one equivalent of TFA and sub‐stoichiometric amount of Yb(hfc)3 allowed the calculation of the e.r. of S‐(−) and R‐(+)‐hyoscyamine.

Results – The method was optimised with various mixtures of (+) and (−)‐hyoscyamine ranging from 50:50 (racaemic mixture, i.e. atropine) to 98.5:1.5. The e.r. measured by NMR on the signals of aromatic C12 and C15 were in agreement with the gravimetrically prepared samples. The method was then applied to an extract of Datura stramonium and S‐(−)‐hyoscyamine was the unique enantiomer.

Conclusion – The study showed that the e.r. determination of atropine/hyoscyamine was achieved with a routine NMR spectrometer, using CLSR/TFA on pure compounds as well as on the crude extract of Datura stramonium. Copyright © 2010 John Wiley & Sons, Ltd.
Validated Method for the Quantification of Atractylenolide III in Different Processed Products of Rhizoma Atractylodes Macrocephalae
Authors: Chen Qinhua , Li Peng , Zheng Fang , He Jing , Yi Yong
Published: August 2010

Introduction – Rhizoma Atractylodes Macrocephalae (RAM) contains several sesquiterpene compounds including atractylenolide III (AO‐III). This bioactive compound may be used as a chemical marker for the quality control of different processed RAM products.

Objective – To develop and validate an RP‐HPLC method for the quantitative determination of AO‐III in RAM and in a variety of processed RAM products.

Methodology – HPLC was carried out using a Kromssil C18 RP‐column eluted with methanol–water (70:30) at a flow rate of 1.0 mL/min and with UV detection at 220 nm. Full validation was performed using standard methods.

Results – The linear range of AO‐III was 5–50 µg/mL; the regression equation was y = 10210x + 11194 (r = 0.9994) and the average recovery was 101.08% (RSD = 0.98%). The detection and quantification limits for AO‐III were determined to be 0.005 and 0.018 µg/mL at signal‐to‐noise ratios of approximately 3:1 and 10:1, respectively.

Conclusion – The described HPLC method is appropriate for quality assurance and differentiation of AO‐III in RAM and different processed products.
Development of chromatographic and free radical scavenging activity fingerprints by thin‐layer chromatography for selected Salvia species
Authors: Cieśla Łukasz , Staszek Dorota , Hajnos Michał , Kowalska Teresa , Waksmundzka‐Hajnos Monika
Published: August 2010

Introduction – Plant‐derived free radical scavengers have become the subject of intensive scientific interest. Recently, the concept of coupling chromatographic fingerprints with biological fingerprinting analysis has gained much attention for the quality control of plant extracts. However, identification of free radical scavenging activity of each single compound in a complex mixture is a difficult task. Thin‐layer chromatography with post‐chromatographic derivatisation with the methanol solution of DPPH can be a valuable tool in such analyses.

Objective – Development of chromatographic and free radical scavenging fingerprints of nineteen Salvia species grown and cultivated in Poland.

Methodology – Chromatography was performed on the silica gel layers with use of two eluents, one for the resolution of the less polar compounds, and the other one for the resolution of the medium and highly polar ones. The plates were sprayed with the vanillin–sulfuric acid reagent to produce chemical fingerprints, and with DPPH solution to generate free radical scavenging fingerprints.

Results – With four Salvia species, it was revealed that their strong free radical scavenging properties are not only due to the presence of polar flavonoids and phenolic acids, but also due to the presence of several free radical scavengers in the less polar fraction. Because of the similarities in both the chromatographic and the free radical scavenging fingerprints, S. triloba can be introduced as a possible equivalent of the pharmacopoeial species, S. officinalis.

Conclusion – Fingerprints developed in the experiments proved useful for the analysis of complex extracts of the different Salvia species. Copyright © 2010 John Wiley & Sons, Ltd.
Analysis of marker compounds with anti‐platelet aggregation effects in mailuoning injection using platelet binding assay combined with HPLC‐DAD‐ESI‐MS and solid‐phase extraction technique
Authors: Yu Li , Li Yingbin , Fan Hongwei , Duan Jinao , Zhu Quan , Li Shaoping
Published: August 2010

Introduction – Mailuoning is prepared from a traditional formula of Chinese medicines and widely used as an antithrombotic agent. In this study, the platelet binding assay was used as a novel biospecific separation and analysis method to explore its active constituents, which could be considered as marker compounds for quality control.

Objective – To establish a rapid and simple method to predict marker compounds in herbal medicine injection and evaluate the effects of those compounds.

Material and methods – Platelets were used to bind and separate constituents. Binding constituents were analysed and taken as potential active compounds for further evaluation. Solid‐phase‐extraction was adopted to improve sensitivity. HPLC‐DAD and ESI‐MS were used to determine the binding constituents.

Results – Five compounds were extracted through the platelet binding process and identified as neochlorogenic acid, caffeic acid, isochlorogenic acid and their isomers. Caffeic acid was selected for the flow cytometric assay to test its effect on platelets activation, which was determined by CD62P (P‐selectin) expression. The results indicated that caffeic acid could significantly inhibit platelet activation while chlorogenic acid did not.

Conclusion – Caffeic acid could be considered as a marker compound of Mailuoning injection due to its anti‐platelet effect. The study also suggested that platelet binding assay combined with some preconcentration technique could be efficiently used to predict anti‐platelet compounds in complicated herbal medicines. Copyright © 2010 John Wiley & Sons, Ltd.
UV‐nano‐imprint lithography technique for the replication of back reflectors for n‐i‐p thin film silicon solar cells
Authors: Söderström K. , Escarré J. , Cubero O. , Haug F.‐J. , Perregaux S. , Ballif C.
Published: August 2010

Texturing of interfaces in thin film silicon solar cells is essential to enhance the produced photocurrent and thus the efficiencies. A UV nano‐imprint‐lithography (UV‐NIL) replication process was developed to prepare substrates with textures that are suitable for the growth of n‐i‐p thin film silicon solar cells. Morphological and optical analyses were performed to assess the quality of the replicas. A comparison of single junction amorphous solar cells on the original structures and on their replicas on glass revealed good light trapping and excellent electrical properties on the replicated structures. A tandem amorphous silicon/amorphous silicon (a‐Si/a‐Si) cell deposited on a replica on plastic exhibits a stabilized efficiency of 8.1% and a high yield of 90% of good cells in laboratory conditions. It demonstrates the possibility to obtain appropriate structure on low cost plastic substrate. Copyright © 2010 John Wiley & Sons, Ltd.
Role of hydrogen in the surface passivation of crystalline silicon by sputtered aluminum oxide
Authors: Li Tsu‐Tsung Andrew , Cuevas Andres
Published: August 2010

Aluminum oxide films can provide excellent surface passivation on both p‐type and n‐type surfaces of silicon wafers and solar cells. Even though radio frequency magnetron sputtering is capable of depositing aluminum oxide with concentrations of negative charges comparable to some of the other deposition methods, the surface passivation has not been as good. In this paper, we compare the composition and bonding of aluminum oxide deposited by thermal atomic layer deposition and sputtering, and find that the interfacial silicon oxide layer and hydrogen concentration can explain the differences in the surface passivation. Copyright © 2010 John Wiley & Sons, Ltd.
Temporal stability of personality traits and disorders within substance dependent patients
Authors: Samuel Douglas B. , Ball Samuel A.
Published: August 2010

The current study evaluated the temporal stability of personality disorders (PD) and traits as assessed by the Schedule for Nonadaptive and Adaptive Personality (SNAP) within a sample being treated for substance dependence in a residential TC. Temporal stability coefficients were similar to the few previous studies with clinical samples and comparable retest intervals; however, the current study extended previous work by examining mean‐level stability of the PD scales. While most SNAP scales remained stable or decreased over 6 months of active psychotherapy, increases on some scales (e.g. workaholism as well as antisocial, narcissistic and obsessive–compulsive PDs) raised compelling questions. These findings suggest additional research on the stability and validity of the SNAP in treatment samples. Copyright © 2010 John Wiley & Sons, Ltd.
Ring inversion process for a series of 3,5‐dialkyl‐1‐oxa‐3,5‐diazacyclohexanes: 1H DNMR study and semiempirical calculations
Authors: DuBray Cecelia M. , Gerber Cody L. , McCulla Ryan D. , Oakland Angie J. , Schwartz Keith D. , Eliason Robert , Brown Jay H.
Published: August 2010

The ring inversion process for a series of 3,5‐dialkyl‐1‐oxa‐3,5‐diazacyclohexanes was studied using proton dynamic nuclear magnetic resonance (1H DNMR) spectroscopy in conjunction with semiempirical calculations. At low temperature, the ring methylene protons decoalesced into two AB spin systems in a 2:1 ratio. Lineshape simulations of the DNMR spectra provided first‐order rate constants for magnetic exchange. The energy barrier for each inversion reaction was calculated from the respective rate constants. In general, as the size of the N‐alkyl group increased, the barrier to ring inversion decreased. A similar trend was seen in semiempirical calculations that modeled the ring inversion process. Copyright © 2010 John Wiley & Sons, Ltd.
Hyperbranched perfluorinated poly(phenylene germanes) obtained by polycondensation of A2B2 and AB3 monomers
Authors: Gasilova Ekaterina R. , Saprykina Natalia N. , Zamyshlyayeva Olga G. , Semchikov Yurij D. , Bochkarev Mihail N.
Published: August 2010

A set of new hyperbranched (HB) perfluorinated poly(phenylene germanes) PPGs, whose connectivity is supported by germanium atoms, was synthesized via an activated copolycondensation of AB3, HGe(C6F5)3 and A2B2, H2Ge(C6F5)2 monomers. Light scattering showed that the content of the AB3 and A2B2 reagents and the sequence of their activation affect the molecular mass and the conformation of PPGs. Morphology of the subaggregates, examined with scanning electron microscopy (SEM) at different magnifications, demonstrated their fractal structure. The conformations of individual PPG macromolecules, obtained with light scattering, were in accord with the morphology of the subaggregates observed with SEM. This allowed to conclude that the fractal approach can be applied up to the scale of the self‐assembly of dendrons during the reaction. The branching structure was analyzed with 19F nuclear magnetic resonance (NMR). The chemical shifts of the main‐chain fluorines depended on the proximity of the C6F4 links to the germanium anion because of the redistribution of the germanium anion charge along the branches via σ–π conjugation. The interdendron links are due to the knots originating from the A2B2 monomer, since they contain nonreacted hydrogens. The interdendron links increase the molecular mass of the copolymers with respect to that of the AB3 homopolymer whose molecular mass cut‐off is due to the entrapment of the focal ion pair. Copyright © 2010 John Wiley & Sons, Ltd.
The influence of organic solvent and ionic liquids on the selective formation of 2‐(2‐ethylhexyl)‐3‐phenyl‐1,2‐oxaziridine mediated by lipases
Authors: Bitencourt Thiago Bergler , Nascimento Maria da Graça
Published: August 2010

This paper describes the influence of the addition of ionic liquids (ILs) based on [BMIm][X], where [X] = SCN, Cl, BF4, and PF6, on the chemo‐enzymatic oxidation of N‐benzyliden‐2‐ethylhexylamine to form the corresponding E‐ and Z‐isomers of oxaziridines mediated by Pseudomonas sp. (PSL) and Candida antarctica (CAL‐B) lipases in various organic solvents at room temperature (25 °C) with urea hydrogen peroxide (UHP). The results showed that the use of different organic solvents in the presence of ILs, critically changes the conversions (5–99%) and the isomeric ratio E:Z, (50–100% E‐isomer) of the products formed. Copyright © 2010 John Wiley & Sons, Ltd.
Surface Morphology of Heterogeneous Nanocrystalline Rutile/Amorphous Anatase TiO2 Films Grown by Reactive Pulsed Magnetron Sputtering
Authors: Gago Raúl , Vinnichenko Mykola , Redondo‐Cubero Andrés , Czigány Zsolt , Vázquez Luis
Published: August 2010

Titanium dioxide films were grown on unheated substrates by mid‐frequency (100 kHz) reactive pulsed magnetron sputtering at different O2 partial pressures in an Ar/O2 atmosphere. X‐ray diffraction and absorption measurements reveal a transition from amorphous anatase to nanocrystalline rutile with [O2], with a mixture of both phases at intermediate values. Atomic force microscopy shows that the promotion of rutile is accompanied by surface roughening due to the apparition of hollow structures (holes) on the surface, in contrast with the extremely smooth morphology of amorphous anatase films. The number and size of holes increase with [O2] and growth time in such a way that they eventually coalesce and percolate to lead to a rough surface for those growth conditions for which a rutile rich film is obtained. Transmission electron microscopy analysis shows the growth evolution of a heterogeneous phase mixture and provides unambiguous correlation between the hole (smooth) morphology and the underlying rutile (anatase) phase. Therefore, the surface morphology results from the slower local growth rate of nanocrystalline rutile compared to that of the surrounding amorphous anatase flat regions as well as from the fast (slow) lateral (vertical) growth rate of the rutile domains.

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The crystal structure Escherichia coli Spy
Authors: Kwon Eunju , Kim Dong Young , Gross Carol A. , Gross John D. , Kim Kyeong Kyu
Published: August 2010

Escherichia coli spheroplast protein y (EcSpy) is a small periplasmic protein that is homologous with CpxP, an inhibitor of the extracytoplasmic stress reponse. Stress conditions such as spheroplast formation induce the expression of Spy via the Cpx or the Bae two‐component systems in E. coli, though the function of Spy is unknown. Here, we report the crystal structure of EcSpy, which reveals a long kinked hairpin‐like structure of four α‐helices that form an antiparallel dimer. The dimer contains a curved oval shape with a highly positively charged concave surface that may function as a ligand binding site. Sequence analysis reveals that Spy is highly conserved over the Enterobacteriaceae family. Notably, three conserved regions that contain identical residues and two LTxxQ motifs are placed at the horizontal end of the dimer structure, stablizing the overall fold. CpxP also contains the conserved sequence motifs and has a predicted secondary structure similar to Spy, suggesting that Spy and CpxP likely share the same fold.
Conductance of functionalized nanotubes, graphene and nanowires: from ab initio to mesoscopic physics
Authors: Blase X. , Adessi C. , Biel B. , Lopez‐Bezanilla A. , Fernández‐Serra M.‐V. , Margine E. R. , Triozon F. , Roche S.
Published: August 2010

We review recent theoretical results aiming at understanding the impact of doping and functionalization on the electronic transport properties of nanotubes, nanowires and graphene ribbons. On the basis of ab initio calculations, the conductance of micrometer long tubes or ribbons randomly doped or grafted can be studied, allowing to extract quantities at mesoscopic length scales such as the elastic mean free path and localization length. While the random modification of a 1D conducting channel leads generaly to a significant loss of conductance, strategies can be found to either exploit or limitate such a detrimental effect. Spin‐filtering in transition metal doped nanotubes, the opening of a mobility gap in graphene ribbons, and the choice of molecules to limitate backscattering in covalently functionalized tubes are examples that will be discussed.

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Symbolic representation of a nanotube filled with Cobalt atoms or clusters with subsequent optimal spinvalve effect (see text).
Multi‐wall carbon nanotubes – a vehicle for targeted Irinotecan drug delivery
Authors: Tripisciano Carla , Rümmeli Mark H. , Chen Xuecheng , Borowiak‐Palen Ewa
Published: August 2010

Chemotherapeutics, administered to defeat neoplastic disease, generally interfere with the growth of cancer cells, eventually destroying them. Since the growth of normal cells may also be affected, serious adverse effects may occur. In addition, many medications might not be properly delivered to the target area because of susceptibility to precocious enzymatic degradation in the systemic circulation. An attractive method to safely deliver anticancer drugs to targeted tissues is to employ carbon nanotubes (CNTs) as a transport vehicle. Here we present a study on the encapsulation of the antineoplastic agent Irinotecan within multi‐wall carbon nanotubes (MWCNTs). We also study the pH‐dependent release of the guest molecules from the nanotubes cavity to phosphate and acetate buffers.

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Schematic representation of Irinotecan filled MWCNTs.
Functionalization of graphene with transition metals
Authors: Zólyomi V. , Rusznyák Á. , Koltai J. , Kürti J. , Lambert C. J.
Published: August 2010

We study the strength of the binding of 4d and 5d transition metals on a graphene sheet in the limit of low‐ and high‐coverage using first principles density functional theory. A database of the binding energies is presented. Our results show that Mo, Hf, Ta, and W bind strongest to the graphene sheet. We find a charge transfer of ≈0.01 electrons per carbon atom from the transition metal to the graphene sheet.
Band offset and interface chemistry of HfO2/Si (001) prepared by electron‐beam evaporation in ultrahigh vacuum using atomic oxygen
Authors: Run Xu , Minyan Tang , Zhijun Yan , Linjun Wang , Yiben Xia , Fei Xu
Published: August 2010

The band offset and interface chemistry of HfO2 films prepared by ultrahigh‐vacuum electron‐beam evaporation was investigated by synchrotron radiation photon electron spectroscopy (SRPES). A relatively large valence band (VB) offset of the HfO2 film with Si was determined to be 3.56 eV. Both the Hf‐silicate and a small number of HfSi bonds were formed at the interface of HfO2/Si. This HfSi bond, which cannot be prevented completely in an ultrahigh‐vacuum preparation system using the Hf metallic source despite the atomic oxygen source adopted, may be mainly responsible for this large value of VB offset of HfO2/Si(001). This result also suggests that metal–silicon bonds at the interface of high k oxides on Si may generally lead to a larger VB offset than that with all silicon atoms at the interface bonding directly with oxygen.
Unlinking absorption and haze in thin film silicon solar cells front electrodes
Authors: Boccard Mathieu , Cuony Peter , Battaglia Corsin , Despeisse Matthieu , Ballif Christophe
Published: August 2010

We study the respective influence of haze and free carrier absorption (FCA) of transparent front electrodes on the photogenerated current of micromorph thin film silicon solar cells. To decouple the haze and FCA we develop bi‐layer front electrodes: a flat indium tin oxide layer assures conduction and allows us to tune FCA while the haze is adjusted by varying the thickness of a highly transparent rough ZnO layer. We show how a minimum amount of FCA leads only to a few percents absorption for a single light path but to a strong reduction of the cell current in the infrared part of the spectrum. Conversely, a current enhancement is shown with increasing front electrode haze up to a saturation of the current gain. This saturation correlates remarkably well with the haze of the front electrode calculated in silicon. This allows us to clarify the requirements for the front electrodes of micromorph cells. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mixtures of Uncaria and Tabebuia extracts are potentially chemopreventive in CBA/Ca mice: a long‐term experiment
Authors: Budán Ferenc , Szabó István , Varjas Tímea , Nowrasteh Ghodratollah , Dávid Tamás , Gergely Péter , Varga Zsuzsa , Molnár Kornélia , Kádár Balázs , Orsós Zsuzsa , Kiss István , Ember István
Published: August 2010

A long‐term experimental animal model was developed by our research group for the evaluation of potential chemopreventive effects. The inhibitory effects of agents on carcinogen (7,12‐dimethylbenz[a]anthracene (DMBA) induced molecular epidemiological biomarkers, in this case the expression of key onco/suppressor genes were investigated.

The expression pattern of c‐myc, Ha‐ras, Bcl‐2, K‐ras protooncogene and p53 tumour suppressor gene were studied to elucidate early carcinogenic and potential chemopreventive effects. The consumption of so‐called Claw of Dragon tea (CoD™ tea) containing the bark of Uncaria guianensis, Cat's Claw (Uncaria sp. U. tomentosa) and Palmer trumpet‐tree (Tabebuia sp. T. avellanedae) was able to decrease the DMBA‐induced onco/suppressor gene overexpression in a short‐term animal experiment. In a following study CBA/Ca mice were treated with 20 mg/kg bw DMBA intraperitoneally (i.p.) and the expression patterns of onco/suppressor genes were examined at several time intervals. According to the examined gene expression patterns in this long‐term experiment the chemopreventive effect of CoD™ tea consumption could be confirmed. Copyright © 2010 John Wiley & Sons, Ltd.