bluuebunny/crossref_metadata_2025 huggingface dataset:
The efficacy of Echinacea in a 3‐D tissue model of human airway epithelium
Authors: Sharma M. , Schoop R. , Hudson JB
Published: December 2009

We evaluated the antirhinovirus efficacy of a standardized preparation of Echinacea purpurea (Echinaforce®) in a 3‐dimensional organotypic model of normal human airway epithelium (EpiAirway™ tissue). Individual replicate tissue samples, maintained as inserts in culture for 3 days or 3 weeks, were infected with rhinovirus type 1A (RV1A), Echinacea alone, a combination of the two, or medium only. None of the treatments affected the histological appearance or integrity of the tissues, all of which maintained a high level of cell viability and preservation of cilia. RV infection resulted in increased mucopolysaccharide inclusions in the goblet cells, but this feature was reversed by Echinacea treatment. This result was confirmed by measurements of mucin secretion, which was stimulated by RV but reversed by Echinacea, suggesting that mucus production during colds could be ameliorated by Echinacea. We did not find evidence of virus replication, although the RV‐infected tissues secreted substantial amounts of the pro‐inflammatory cytokines IL‐6 and IL‐8 (CXCL8), and this response was reversed by Echinacea treatment. These results confirmed previous findings derived from studies of bronchial and lung epithelial cell lines, namely, that RV infection results in a substantial inflammatory response in the absence of virus replication. Copyright © 2009 John Wiley & Sons, Ltd.
The ethyl acetate extract of Phellinus linteus grown on germinated brown rice induces G0/G1 cell cycle arrest and apoptosis in human colon carcinoma HT29 cells
Authors: Park Hye‐Jin , Choi Se Young , Hong Se mi , Hwang Sung Gu , Park Dong Ki
Published: December 2009

It is well known that Phellinus linteus has a variety of biological functions, such as antitumor and immunomodulating activities. In our previous studies, we developed a P. linteus grown on germinated brown rice (PBR) and found that organic solvent extracts of PBR possessed immunomodulating activity to regulate a balance of cytokine network in mice. The components of PBR are ergosterol peroxide, γ‐aminobutyric acid (GABA) and B‐glucan. In this study, we demonstrate that an organic solvent extract of P. linteus grown on PBR induced apoptotic cell death through the induction of G0/G1 arrest of cell cycle and the apoptosis via DNA fragmentation in human colon carcinoma HT‐29 cells. Cell death induced by the extract of P. linteus grown on PBR was shown to be associated with the upregulation of p21CIP1/WAF1, the downregulation of cyclin D1, anti‐apoptotic protein, Bcl‐2, the release of cytochrome c, and the activation of caspase‐9, caspase‐3 and caspase‐8. This study suggests that the ethyl acetate extract of P. linteus grown on PBR induces apoptosis accompanied by cell cycle arrest at G0/G1 phase and regulates apoptosis‐regulatory proteins, which may be applicable to anticancer therapy. Copyright © 2009 John Wiley & Sons, Ltd.
Modification of cellulose‐based packaging materials for enzyme immobilization
Authors: Mascheroni Erika , Capretti Giorgio , Marengo Mauro , Iametti Stefania , Mora Luigi , Piergiovanni Luciano , Bonomi Francesco
Published: December 2009

Active cellulose‐based packaging materials were prepared by binding lysozyme to paper modified with anionic polyelectrolytes. Polyelectrolytes improve the paper binding capacity towards the positively charged lysozyme and play a protective role towards lysozyme activity during the paper‐making process. The charge density of paper was increased by incorporating carboxymethylcellulose (CMC) or polygalacturonic acid (PGA). The presence of either CMC or PGA greatly increased the amount of bound lysozyme, and the stability of its binding towards buffers or towards non‐ionic chaotropes which disrupt the three dimensional structure in macromolecules (urea, 8 M). Binding of lysozyme to modified papers was sensitive to anionic detergents (sodium dodecyl sulphate, 1%) and to non‐chaotrope salts (NaCl, 0.5M). These data provide information about the nature of the interactions between the protein and the various types of paper, and provide insights on how to preserve the activity of lysozyme‐loaded paper. The polymers used for lysozyme immobilization were found to affect only marginally the structural and functional properties of the antimicrobial protein, and to facilitate the recovery of structural features of the protein after heat treatment. Presence of a negative polyelectrolyte (and of CMC in particular) improves the thermal stability of the protein, making it resistant to thermal inactivation, even under the conditions used for drying processes without compromising the paper's mechanical properties. The activity measurements showed that paper‐bound lysozyme retains its lytic (and therefore, antimicrobial) activity against the cell walls of Micrococcus lysodeikticus, the target microrganism used as standard for lysozyme bioassays. Copyright © 2009 John Wiley & Sons, Ltd.
Colonization and succession of stream communities in Glacier Bay, Alaska; What has it contributed to general successional theory?
Authors: Milner Alexander M. , Robertson Anne L.
Published: December 2009

Succession is a key concept in ecology and its study has generated well known and highly debated theories on mechanisms by which communities are assembled, including the relative role of deterministic and stochastic pathways. The contribution of stream ecosystems to general successional theory, particularly primary succession, has been extremely limited due to the lack of long‐term studies on stream channels at a large enough spatial scale. We suggest that the study of succession in streams in Glacier Bay, southeast Alaska where rapid ice recession has occurred may offer one of the few examples of the tolerance model as a major mechanism of macroinvertebrate community assembly; the majority of macroinvertebrate taxa, with the exception of the cold‐tolerant first colonizers, have persisted within the community following colonization. Relative abundance has however changed markedly over time. In contrast, a meiofaunal component of the invertebrate community exhibited poor persistence with numerous extinctions. Stream successional processes may be unique in being closely linked to, and markedly influenced by, processes in other ecosystems, particularly the terrestrial environment. Stream succession in Glacier Bay also demonstrates differences from terrestrial succession in the number of reset mechanisms that can cause communities to significantly shift to an earlier successional stage or at least allow the persistence of early colonizers, including the loss of flow buffering lakes, floods and redd construction by spawning salmon. We suggest in these streams community assembly initially follows deterministic pathways due to the overriding influence of water temperature but as temperatures exceed 7°C then stochastic mechanisms influence succession and community assembly. Copyright © 2009 John Wiley & Sons, Ltd.
Does species trait composition influence macroinvertebrate responses to irrigation water withdrawals: Evidence from the Intermountain West, USA
Authors: Miller Scott W. , Wooster David , Li Judith L.
Published: December 2009

Irrigation water withdrawals are ubiquitous in arid and semi‐arid regions; however, predictable macroinvertebrate responses have not emerged. Inconsistent responses are frequently attributed to the amount of water withdrawn, while physicochemical and biological differences among systems remain unstudied. In this study, we sought to determine if species traits influence macroinvertebrate responses to water withdrawals. We sampled above and below 12 independent water diversions experiencing discharge reductions greater than 75% in central and eastern Oregon and Washington, USA. When considering all 12 rivers, we observed significant alterations to the hydrologic environment, in addition to increased algal standing stocks, silt cover and minimum temperatures; however, macroinvertebrate responses were limited to increased downstream densities, as indices and community composition did not significantly change. Functionally, species traits were more sensitive than structural indices; proportional abundance for 12 of 52 species traits significantly differed above and below all points of diversion. Trait changes suggest a shift in functional composition to compensate for hydrologic alterations and reduced habitat area. Grouping references sites (upstream) by species trait composition revealed a strong ambient gradient of increasing resistance and resilience from high to low elevations; however, we did not find evidence for differential susceptibility to water withdrawals among trait‐based reference groups. Though water withdrawals changed the representation of select species traits, frequencies of trait states most vulnerable to water withdrawals were too homogenously distributed among sites to elicit differential responses among trait‐based reference groups. At larger spatial scales or among disparate hydrologic regimes, grouping systems by species traits will likely reduce variability and offer a more general currency for detecting perturbation response relationships. Copyright © 2009 John Wiley & Sons, Ltd.
Contrasting stream stability characteristics in adjacent urban watersheds: Santa Clara Valley, California
Authors: Jordan B. A. , Annable W. K. , Watson C. C. , Sen D.
Published: December 2009

A comparative study of two adjacent stream channels in the Santa Clara Valley region of California provided an opportunity to study the relative effects of multi‐faceted watershed‐urbanization impacts on channel evolution and stability. Berryessa Creek (15.5 km2) and Upper Penitencia Creek (61.3 km2) have similar intrinsic watershed characteristics; however, urbanization processes have imposed distinctly different evolutionary trends in each watershed. The influences of drainage network manipulation, hydrologic routing and engineering infrastructure has resulted in Upper Penitencia Creek remaining relatively stable throughout the course of urbanization, while Berryessa Creek has experienced system‐wide channel instability problems. This study enumerates the many anthropogenic impacts and provides insight into basin alterations that can have either positive or negative feedbacks in maintaining or degrading channel stability throughout the course of urbanization.

Results show that infrastructure that disrupts the bed material sediment continuity (such as large drop structures or sedimentation ponds) generate long‐term downstream channel instabilities leading to channel degradation and continued maintenance. Off‐line flow diversions (in this study percolation ponds) that do not disrupt bed material transport can emulate pre‐urbanization conditions offsetting channel degradation resulting from changes in hydrology. This study also demonstrates the degradational responses of a stream due to losses in riparian vegetation from water table lowering transforming a perennial stream into an ephemeral stream resulting in increased bank instability. The importance of maintaining floodplains for flood access and channel stability has also been identified and compared to conditions of channel encroachment to facilitate maintenance, which have further exacerbated downstream channel degradation, long‐term channel maintenance and dredging. Copyright © 2009 John Wiley & Sons, Ltd.
Ambient mass spectrometry: advances and applications in forensics
Authors: Green F. M. , Salter T. L. , Stokes P. , Gilmore I. S. , O'Connor G.
Published: December 2009

Ambient mass spectrometry (ambient MS) is a powerful and rapidly growing new field that provides high sensitivity MS directly from surfaces at ambient pressure. There is now a rich evidence base in the published literature of the success of these methods for forensic analysis including: detection of explosives at nanogram levels; chemical composition of counterfeit pharmaceutical tablets, detection of drugs of abuse from biological liquids such as urine and plasma; breath analysis of metabolites; and imaging analysis for document verification and fingerprint identification. Recent developments in miniaturised (shoe‐box sized) mass spectrometers have enabled these developments to be translated to portable on‐scene detection and first responder usage. In this review, we illustrate and compare the effectiveness of the most popular and promising techniques of desorption electrospray ionisation (DESI), direct analysis in real time (DART), plasma assisted desorption ionisation (PADI) and extractive electrospray ionisation (EESI). Forensic analysis by its very definition must stand up to scrutiny in a court of law. It is therefore essential that measurements are repeatable, valid, traceable and fit for purpose. The establishment of a measurement infrastructure is therefore essential to ensure that the methods used may be accredited and conform to relevant quality systems and procedures. © Crown copyright 2009. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
Durability of aluminum cooling system in electric power plants
Authors: Deflorian F. , Rossi S. , Fedel M.
Published: December 2009

The final step in gas turbine electric power production plants is the cooling of water after the turbine expansion. In some thermal plants, the temperature reduction of the recycling fluid is partially obtained by heat exchanging with the atmosphere by passing the fluid through huge aluminum heat exchangers. From the corrosion point of view, most critical is the starting step of the power plant, when the aluminum cooling system comes in contact with water for the first time and reaches a surface condition in dynamic equilibrium with the liquid. This paper describes a systematic study of aluminum surface evolution in the cooling system of an electric power plant during the first weeks of operation. Some aluminum samples were placed inside the cooling system in significant locations and removed after scheduled times. The surface conditions of the samples were characterized using surface analyses, electrochemical techniques and microscopic observations. At the same time, the chemical conditions of the recycling fluids were monitored. The obtained results describe the corrosion resistance of the aluminum surface as a function of the conditioning time, proving the growth of a partially protective layer able to produce corrosion decrease during the service time of the energy production plant. Copyright © 2009 John Wiley & Sons, Ltd.
Zur Bemessung von Lochleisten als duktile Verbundmittel in Verbundträgern aus höherfesten Materialien
Authors: Gündel Max , Dürr André , Hauke Bernhard , Hechler Oliver
Published: December 2009

Im Rahmen eines gemeinsamen FuE‐Projekts der HOCHTIEF Construction AG und ArcelorMittal Belval & Differdange S. A. wurden umfangreiche experimentelle und theoretische Untersuchungen an Lochleisten als duktiles Verbundmittel durchgeführt. Ziel der Untersuchung ist die Entwicklung technisch hochwertiger und wirtschaftlicher Verbundbauteile aus höherfesten Werkstoffen (z. B. Beton C50/60 und Stahl S460), [1] bis [4]. Hierbei wurden insbesondere das Tragverhalten, die Traglast, die Duktilität und die Dauerfestigkeit von unterschiedlichen Lochleistenformen sowie das Gesamttragverhalten von Verbundbauteilen mit Lochleisten untersucht. Aufbauend auf den in Versuchen gewonnenen Erkenntnisse wurden Bemessungskonzepte für Lochleisten als Verbundmittel in Verbundträgern aus höherfesten Materialien entwickelt.

Design of aperture plates as ductile shear connectors for composite beams with high strength materials.

Within a joint research project of HOCHTIEF Construction AG and ArcelorMittal Belval & Differdange S. A. various experimental and theoretical investigations in aperture plates, as ductile shear connector for composite members have been carried out. The aim of the research has been to develop technically advanced and economic composite members with the application of high strength materials (e.g. steel S460 and concrete C50/60). The main focus of the research has been put on the load bearing behaviour, ultimate bearing capacity, ductility and fatigue resistance of different types of aperture plates geometries as well as the related overall bearing performance of the composite members with the application of these plates as shear connectors. Based on the conclusions from the experimental test results, design concepts for aperture plates as shear connectors for composite beams with the application of high strength materials have been developed.
Ermüdungsverhalten geschweißter Rohrknoten von Fachwerkverbundbrücken
Authors: Mangerig Ingbert , Romen Norbert
Published: December 2009

Im Verbundbrückenbau werden in letzter Zeit anstatt vollwandiger Ausführungsvarianten vermehrt aufgelöste Fachwerkkonstruktionen aus Stahlhohlprofilen eingesetzt, da diese sowohl in Bezug auf gestalterische Grundsätze als auch hinsichtlich konstruktiver Gesichtspunkte Vorteile versprechen. Hierbei wird insbesondere bei Brückenentwürfen, deren Ausgestaltung eine Vielzahl unterschiedlicher Knotengeometrien erfordert, aus wirtschaftlichen Gründen die Verbindung zwischen Füllstab und Gurtrohr bevorzugt mit direkt geschweißten Knoten anstatt mit Stahlgussknoten ausgeführt. Aufgrund der durch die Knotengeometrie bedingten Spannungskonzentration im Bereich der Schweißnahtkerbe wird der Brückenentwurf bei dieser Ausführungsvariante maßgeblich von der dort vorherrschenden Ermüdungsfestigkeit beeinflusst. Nachdem die in den einschlägigen Normen bereitgestellten Nachweisverfahren gegen Ermüdung für die üblichen im Brückenbau verwendeten Abmessungen nicht anwendbar sind, ist die versuchstechnische Untersuchung zur Absicherung eines ausreichenden Ermüdungswiderstandes bisher unabdingbar. Dieser Beitrag bezieht sich auf insgesamt sieben Versuchskörper, die im Rahmen des Neubaus der Autobahnüberführung Suhl–Lichtenfels auf Ermüdung geprüft wurden.

Fatigue behaviour of welded pipe intersections in steel‐concrete composite bridges.

In the construction of modern steel‐concrete composite bridges, the steel part is increasingly built by circular hollow sections instead of steel plates. This type of bridge design shows advantageous characteristics concerning architectural aspects as well as benefits in the static load transfer. Especially if the design of the truss girder requires a large number of different node geometries, the connection between the braces and the lower and upper chord are for economic reasons preferably build by directly welded nodes instead of cast steel nodes. Due to the local joint discontinuity of the pipe intersections, the stress distribution is enhanced exactly in the area of the welding seams. As a consequence, the limited fatigue behaviour of the pipe intersections represents the critical aspect in the design of tubular truss‐girder bridges. The difficulties in the design of this construction type are due to the fact that the criterions for fatigue verification given in the current codes do not cover the typical dimensions used in bridge design. Therefore until now it is unavoidable to conduct large‐scale tests in order to verify a sufficient fatigue resistance. This article refers to a total of seven specimens tested on fatigue during the construction of the new Highway Overpass Suhl– Lichtenfels.
Längenabhängigkeit des Beulwiderstandes umfangsdruckbeanspruchter stählerner Kreiszylinderschalen
Authors: Ziółko Jerzy , Schneider Werner , Białek Tomasz , Heizig Tomasz , Gettel Marco
Published: December 2009

Das Versagen von Silos und Tanks wird häufig durch Druckunterschiede zwischen Außen‐ und Innendruck verursacht. Obwohl es sich beim Lastfall konstanter Umfangsdruck um einen Basisbeulfall der Kreiszylinderschale handelt, sind selbst hierbei einige Fragen noch nicht geklärt. Vergleicht man die Beulwiderstände, die sich in den technischen Regelwerken nach dem experimentell gestützten spannungsbasierten Beulsicherheitsnachweis ergeben, mit den Versagenslasten, die man bei einem numerisch gestützten Beulsicherheitsnachweis unter Einbeziehung von geometrischen Ersatzimperfektionen ermittelt, ergeben sich Diskrepanzen im Bereich langer Schalen. Im Beitrag werden experimentelle Ergebnisse eines deutsch‐polnischen Kooperationsprojektes vorgestellt, das diesen Widersprüchen nachgeht. Die Auswertung der Ergebnisse zeigt, dass der Beulwiderstand dünnwandiger Schalen unter Umfangsdruck auch von der geometrischen Schalenschlankheit abhängt. Das wird gegenwärtig von den Vorschriften noch nicht erfasst, so dass lange Schalen konservativer als kurze Schalen bemessen werden.

Influence of the length‐to‐radius ratio on the buckling resistance of cylindrical steel shells subject to hoop compression.

The failure of silos and tanks is often caused by differences between outer and inner pressure. Although the load case hoop compression is a basic buckling case of cylindrical shells, there are still some problems that have to be tackled. For long cylinders, discrepancies arise when comparing the buckling resistances calculated from the experimentally based stress design of current design rules with the resistances derived from numerical buckling strength verifications using equivalent geometric imperfections. In the contribution, the experimental results of a German‐Polish research project, concerning that problem, are presented. The evaluation of the results reveals that the buckling resistance of thin‐walled cylindrical steel shells subject to hoop compression also depends on the geometrical slenderness. This fact is neglected in current design rules. Therefore, long cylinders are designed more conservatively than short cylinders.
Seismic assessment of rc buildings by estimation of effective parameters on seismic behaviour using non‐destructive tests
Authors: Moshtagh Ehsan , Massumi Ali
Published: December 2009

Seismic assessment of existing buildings is needed in many cases: change in construction usage (change in applied loads), undesirable construction quality, disparity between standard specimen and technical specification of design, absence of construction plans and modification of codes. Seismic assessment is the first step towards rehabilitation of constructions or other schemes to decrease damages and personal injuries. In this regard, engineers should be able to precisely estimate effective parameters on seismic behaviour, to utilize them in mathematical modelling of structures for increasing their reliability. This aim can be achieved by destructive or non‐destructive tests (NDT). In this paper, NDTs for estimating static and dynamic characteristics of reinforced concrete structures are reviewed. Finally, two essential dynamic NDTs, forced vibration method and ambient vibration method, are discussed in detail, and are proposed for seismic assessment in all kinds of structures. Copyright © 2009 John Wiley & Sons, Ltd.
Experimental and numerical investigation of damaged concrete beams strengthened with FRP composed of different fibres and resins
Authors: Rahai Ali Reza , Saberi Mohammad Reza
Published: December 2009

Strengthening of structures to avoid further damages is inevitable in different conditions. In this paper, to evaluate the effect of fibre‐reinforced polymer (FRP) plates on damaged and non‐damaged members, an extensive experimental programme is reported. Several beam specimens were built. Some specimens were strengthened after loading condition. The damaged specimens strengthened by FRP plates containing two different resins (epoxy or polyester) were tested. Other beam specimens were strengthened by composite plates before loading. Moreover, a numerical modelling procedure was performed, and it showed good agreement with experimental results. Results showed improvements in flexural capacity of damaged beams strengthened by FRP laminates or plates compared with the non‐damaged ones. Copyright © 2009 John Wiley & Sons, Ltd.
Imitator‐to‐innovator S curve and chasms
Authors: Ouyang Hongwu “Sam”
Published: December 2009

Over the past 20 years, some latecomer firms in Korea and China have successfully transformed themselves from imitators into innovators. In this article, we focus on the imitator‐to‐innovator transformation process. We try to answer the following questions: What are the evolutionary paths and mechanisms? What may be the challenges in the transformation process? In this article, we suggest the technological capability building in latecomer firms can be characterized by successive S curves. And we use a five‐phase model and dynamic S curve to analyze their transformation from imitator to innovator. We also discuss the four chasms in the transformation and identify the challenges and three‐level factors facilitating chasm crossings. This article makes two contributions: proposing a new framework for and introducing the S curve and chasm into studying the latecomer firms' development, and elaborating key challenges in and major differences among the four chasms in the imitator‐to‐innovator transformation, which have been neglected in the literature. © 2010 Wiley Periodicals, Inc.
An empirical analysis of risk mitigation in the pharmaceutical industry supply chain: A developing‐country perspective
Authors: Enyinda Chris I. , Mbah Chris H. N. , Ogbuehi Alphonso
Published: December 2009

Global pharmaceutical supply‐chain risk mitigation has become an important issue in the corporate boardroom. This article reports on the empirical findings of the quantification of risks that decision makers consider most important when deciding on a risk portfolio to mitigate and the manner in which risks are prioritized according to their importance. The empirical findings suggest that decision makers attached great importance to counterfeit, Food and Drugs Board, and exchange‐rate fluctuations. With respect to risk‐mitigation strategies, risk reduction is considered most important, followed by risk avoidance. Dynamic sensitivity analysis with respect to a change (increase) in the Food and Drugs Board did not result in any change in the ranking of risk policy options, while a change (increase) in counterfeit resulted in a change in the ranking between risk reduction and risk avoidance. Risk avoidance ranked number one, followed by risk reduction. Implications distilled from this article are far‐reaching for the Ghanaian pharmaceutical firms' managers. © 2010 Wiley Periodicals, Inc.
Cluster‐based coordination and routing framework for wireless sensor and actor networks
Authors: Shah Ghalib A. , Bozyigit Muslim , Hussain Faisal B.
Published: December 2009

In Wireless Sensor Actor Networks (WSAN), sensor nodes perform the sensing task and actor nodes take action based on the sensed phenomena. Generally, the network is configured to observe multiple events and to react upon each individual event accordingly. Time delay, energy efficiency and reliability are three important aspects of WSAN that require special attention. To ensure efficient and reliable operations of such heterogeneous WSAN, new communication protocols are imperative.

In this paper, we propose an integrated cluster‐based coordination and routing (CCR) framework for WSAN, whose prime objective is to ensure reliable action with efficient energy consumption. In CCR, sensor nodes are first configured to form clusters by taking into account the residual energy of nodes and network density. Once the clusters are formed, cluster‐heads coordinate with the actors to forminteractive regions. The reliability of action is addressed in terms of in time data delivery to actors in interactive regions and actor–actor coordination to make sure that an actor perform action in the reported region. A novel real‐time data aggregation (RDA) approach is also incorporated in the framework to conserve energy by minimizing the number of transmissions and achieve fairness. Simulation experiments prove that the framework achieves energy efficiency and reports in‐time event to the actors for reliable actions. Copyright © 2009 John Wiley & Sons, Ltd.
Application of the actuator surface concept to wind turbine rotor aerodynamics
Authors: Sibuet Watters C. , Breton S.P. , Masson C.
Published: December 2009

The structure of blade tip vortices is recognized as a key issue in wind turbine aerodynamic modelling by many researchers in the field. In the search for an intermediate model between full Navier–Stokes and blade‐element momentum simulations, this article presents a method using rotating actuator surfaces to model wind turbine aerodynamics. An actuator surface is a simple planar surface, porous to the flow, which is characterized by velocity and pressure discontinuities, whose action on the flow is achieved through an attached system of forces. These discontinuities and forces are determined from blade‐element analysis and the Kutta–Joukowski relation. After implementing this concept in a three‐dimensional CFD (Computational Fluid Dynamics) method, results are produced for the experimental rotors of NREL and TUDelft. The method is validated against both experimental measurements and the predictions of three other numerical models for wind turbine aerodynamic analysis. Qualitative and quantitative comparisons show that the actuator surface concept agrees well with the other numerical models. In addition to rotor aerodynamic analysis, the actuator surface concept can be used in the study of wake aerodynamics, or as the Eulerian flow solver in hybrid methods. Copyright © 2009 John Wiley & Sons, Ltd.
Modelling–based approach for digital control design for nonlinear WECS in the power system
Authors: Muhando Endusa Billy , Senjyu Tomonobu , Omine Eitaro , Funabashi Toshihisa , Kim Chul‐Hwan
Published: December 2009

The case has been established that the wind power plant must be treated as an integral part of the electric system, thereby constituting the wind energy conversion system. Recent advancement in size and technology of wind turbines requires sophisticated control systems to effectively optimize energy conversion and enhance grid integration. As a first step toward controller design, modelling has become a prerequisite. This paper explores controller design based on modelling the wind speed as a stochastic process, and the wind turbine as a multi‐mass system with a soft shaft linking the turbine with the doubly fed induction generator. A control strategy incorporating a linear quadratic Gaussian (LQG) that relies on state estimation for full‐state feedback is proposed to augment a linear controller for generator torque control. The control objectives are to reduce stresses on the drivetrain and to ensure operation geared toward optimal power conversion. This study focuses on above‐rated wind speeds, and the LQG's main purpose is to add damping to the drivetrain, thereby minimizing cyclic fatigue, while a pitch control mechanism prevents rotor overspeed, thereby maintaining rated power. Simulations show the efficacy of the proposed paradigm in meeting the control objectives. Copyright © 2009 John Wiley & Sons, Ltd.
Morphisme de Baum-Connes tordu par une représentation non unitaire
Authors: Gomez-Aparicio Maria Paula
Published: December 2009

Soit G un groupe localement compact et ρ une représentation de dimension finie de G non unitaire. On définit des algèbres de Banach analogues aux C*-algèbres de groupe, C*(G) et C*r(G), en considérant l'ensemble des représentations de la forme ρ ⊗ π, où π parcourt un ensemble de représentations unitaires de G. On calcule la K-théorie de ces algèbres pour une large classe de groupes vérifiant la conjecture de Baum-Connes.
Effect of organically and conventionally produced diets on jejunal gene expression in chickens
Authors: de Greeff Astrid , Huber Machteld , van de Vijver Lucy , Swinkels Willem , Parmentier Henk , Rebel Johanna
Published: December 2009

Using a nutrigenomics approach we studied the response of second-generation chickens at a transcriptional level to organically grown feed ingredients compared with conventionally grown feed ingredients. Both diets consisted of the same amounts of ingredients, the only difference was the production method. Gene expression was analysed in jejuni using whole genome chicken cDNA arrays. After analysis, forty-nine genes were found to be differentially regulated between chickens fed on the different diets, independent of their genetic background. Of these forty-nine genes, seven genes were involved in cholesterol biosynthesis. Genes involved in cholesterol biosynthesis were higher expressed in jejuni from organically fed birds. Other genes found to be regulated were involved in immunological processes, such as B-G protein (part of chicken major histocompatibility complex), chemokine ah221, and the immunoglobulin heavy chain. Using quantitative PCR the effect of genetic background on the differential expression of genes was studied. Differences in gene expression existed between animals fed different diets as well as between different chicken lines. This indicated that diet and genetic background influence the transcriptional response of the jejunum. This is the first time that significant differences in gene expression were shown between animals on diets with organically or conventionally produced ingredients.
Association of n-3 long-chain PUFA and fish intake with depressive symptoms and low dispositional optimism in older subjects with a history of myocardial infarction
Authors: van de Rest Ondine , de Goede Janette , Sytsma Femke , Oude Griep Linda M. , Geleijnse Johanna M. , Kromhout Daan , Giltay Erik J.
Published: December 2009

Individuals with CHD are at increased risk of poor mental well-being. Dietary intake of EPA and DHA, the main n-3 fatty acids from fish, may be beneficial to mental well-being. We examined the association of EPA+DHA and fish intake with mental well-being in 644 participants, aged 60–80 years, with a history of myocardial infarction. Habitual food intake was assessed with a 203-item FFQ. Depressive symptoms were assessed with the self-report geriatric depression scale, and dispositional optimism was assessed with the revised life orientation test (LOT-R) and a four-item questionnaire (4Q). In Cox-regression models modified for cross-sectional analyses, we adjusted for sex, age, energy intake, BMI, family history of depression, education, marital status, smoking, physical activity and intake of saturated fat, alcohol and fibre. Compared with the lower tertile, subjects in the higher tertile of EPA+DHA intake had a lower prevalence of depressive symptoms, but this association was not statistically significant (prevalence ratio (PR) 0·78; 95 % CI 0·50, 1·22, P-trend 0·27). The higher tertile of EPA+DHA intake was positively associated with dispositional optimism measured with the 4Q (PR 0·69; 95 % CI 0·46, 1·03, P-trend 0·05), but not according to the LOT-R. Fish intake was not related to either depressive symptoms or dispositional optimism. In conclusion, intake of EPA+DHA was positively associated with dispositional optimism assessed with the 4Q, but not with optimism assessed with the LOT-R or with depressive symptoms.
The Attribution of Credit and Blame to Governments and Its Impact on Vote Choice
Authors: Marsh Michael , Tilley James
Published: December 2009

This article examines how voters attribute credit and blame to governments for policy success and failure, and how this affects their party support. Using panel data from Britain between 1997 and 2001 and Ireland between 2002 and 2007 to model attribution, the interaction between partisanship and evaluation of performance is shown to be crucial. Partisanship resolves incongruities between party support and policy evaluation through selective attribution: favoured parties are not blamed for policy failures and less favoured ones are not credited with policy success. Furthermore, attributions caused defections from Labour over the 1997–2001 election cycle in Britain, and defections from the Fianna Fáil/Progressive Democrat coalition over the 2002–07 election cycle in Ireland. Using models of vote switching and controlling for partisanship to minimize endogeneity problems, it is shown that attributed evaluations affect vote intention much more than unattributed evaluations. This result holds across several policy areas and both political systems.
Land Redistribution/Restitution in South Africa: A Model of Multiple Values, as the Past Meets the Present
Authors: Gibson James L.
Published: December 2009

This article investigates support for redistributive land policy in contemporary South Africa. From a large survey conducted in 2004, the author assesses whether contemporary policy preferences reflectedegocentric instrumentalism– direct and immediate profit from redistributive policies – orsymbolic justice– non-instrumental concern for contemporary and historical injustices against groups. Analysis of the data decidedly favours the symbolic justice hypothesis. Land redistribution is a symbolic issue for most black South Africans, grounded in values connected to land as a symbol and in concern for the historical injustices of apartheid and colonialism. Because land policy preferences are so strongly associated with concerns for historical injustices against groups, the land issue remains volatile and resistant to ‘simple’ economic solutions. Land is thus an example of historical injustices colliding with demands for contemporary fairness.
Epistatic interactions attenuate mutations affecting startle behaviour inDrosophila melanogaster
Authors: YAMAMOTO AKIHIKO , ANHOLT ROBERT R. H. , MACKAY TRUDY F. C.
Published: December 2009

Epistasis is an important feature of the genetic architecture of quantitative traits. Previously, we showed that startle-induced locomotor behaviour ofDrosophila melanogaster, a critical survival trait, is highly polygenic and exhibits epistasis. Here, we characterize epistatic interactions among homozygousP-element mutations affecting startle-induced locomotion in theCanton-Sisogenic background and in 21 wild-derived inbred genetic backgrounds. We find pervasive epistasis for pairwise combinations of homozygousP-element insertional mutations as well as for mutations in wild-derived backgrounds. In all cases, the direction of the epistatic effects is to suppress the mutant phenotypes. The magnitude of the epistatic interactions in wild-derived backgrounds is highly correlated with the magnitude of the main effects of mutations, leading to phenotypic robustness of the startle response in the face of deleterious mutations. There is variation in the magnitude of epistasis among the wild-derived genetic backgrounds, indicating evolutionary potential for enhancing or suppressing effects of single mutations. These results provide a partial glimpse of the complex genetic network underlying the genetic architecture of startle behaviour and provide empirical support for the hypothesis that suppressing epistasis is the mechanism underlying genetic canalization of traits under strong stabilizing selection. Widespread suppressing epistasis will lead to underestimates of the main effects of quantitative trait loci (QTLs) in mapping experiments when not explicitly accounted for. In addition, suppressing epistasis could lead to underestimates of mutational variation for quantitative traits and overestimates of the strength of stabilizing selection, which has implications for maintenance of variation of complex traits by mutation–selection balance.
Allergic fungal rhinosinusitis: detection of fungal DNA in sinus aspirate using polymerase chain reaction
Authors: El-Morsy S M , Khafagy Y W , El-Naggar M M , Beih A A
Published: December 2009

Objective:

This study investigated allergic fungal rhinosinusitis cases, and aimed to compare the detection of fungi in sinus aspirate by culture and by polymerase chain reaction assay, and to relate the presence of fungi in the nasal sinuses to the type of fungal allergen causing disease.

Methods:

Sixty-eight cases of allergic fungal rhinosinusitis underwent fungal culture and polymerase chain reaction assay for universal fungal, aspergillus and bipolaris DNA. Aspergillus-specific immunoglobulin E levels were measured in sinus aspirate, and total serum immunoglobulin E levels were calculated. A control group of 10 cases was included in the study.

Results:

Of the 68 allergic fungal rhinosinusitis cases, only 42 (61.7 per cent) had positive fungal cultures; of the 10 controls, only three (30 per cent) had positive cultures. Species from the dematiaceous family were most commonly grown, being isolated in 30 cases (71.4 per cent). Bipolaris was the most commonly isolated species (18 cases) followed by curvularia (11 cases) and alternaria (one case). Polymerase chain reaction assay detected fungal DNA in all the allergic fungal rhinosinusitis cases and also in four controls (40 per cent). Ten patients (of 68; 14.7 per cent) were positive forAspergillus fumigatusspecific immunoglobulin E. The mean concentration of this immunoglobulin was 11.32 ± 4.12 IU/ml in patients and 0 IU/ml in controls, a statistically significant difference.

Conclusion:

Detection of fungal DNA in nasal aspirate by polymerase chain reaction was superior to fungal cultures as a method of detecting fungal growth. In allergic fungal rhinosinusitis, fungal growth is not always accompanied by an allergic reaction.
Complications of bone-anchored hearing aid implantation
Authors: Hobson J C , Roper A J , Andrew R , Rothera M P , Hill P , Green K M
Published: December 2009

Introduction:

Bone-anchored hearing aid implantations have been performed in Manchester for over 20 years. This study examined a range of variables that can occur during the implantation process, and the effect they may have on successful outcome.

Method:

Retrospective study and literature review.

Location:

Tertiary referral centre in central Manchester.

Results:

Details of 602 bone-anchored hearing aid implantation procedures were retrieved from the departmental database. The overall complication rate was 23.9 per cent. The rate of revision surgery was 12.1 per cent.

Conclusion:

This study involved a significantly larger number of patients than any previously reported, similar study. Possible reasons for differences in outcomes, and recommendations for best practice, are discussed.
Ovine toxoplasmosis
Authors: INNES ELISABETH A. , BARTLEY PAUL M. , BUXTON DAVID , KATZER FRANK
Published: December 2009

Congenital infection withToxoplasma gondiiis an important cause of abortion in sheep worldwide. The cat is the definitive host of the parasite, and infected cats may shed millions of oocysts in their faeces resulting in extensive environmental contamination and an important source of infection for grazing herbivorous animals. Studies looking at development of specific antibodies in sheep, as an indicator of exposure toT. gondii, have shown that there is an increase in seroprevalence associated with age indicating that most infections in sheep occur following birth. The stage of gestation when transplacental transmission ofT. gondiito the developing foetus occurs is critical in determining the clinical outcome. The importance of endogenous transplacental transmission in persistently infected ewes and its clinical importance is a subject of current debate. Ewes infected prior to mating develop immune responses that help protect against disease in a subsequent pregnancy and also against experimental challenge administered during pregnancy. Both innate and adaptive immune responses are activated followingT. gondiiinfection and experiments involving the chronic cannulation of peripheral lymph nodes in sheep have allowed the dynamics of the immune responses to be analysed in real time. A live vaccine, Toxovax® is the only commercially available vaccine worldwide to protect against congenital toxoplasmosis.
First language and target language in the foreign language classroom
Authors: Littlewood William , Yu Baohua
Published: December 2009

For many decades, foreign language teaching has been dominated by the principle that teachers should use only the target language (TL) and avoid using the mother tongue (L1) except as a last resort. However, reports show that teachers make extensive use of the L1. This paper illustrates this discrepancy and considers some main reasons for it. It suggests a framework of principles for balancing L1 and TL use in the classroom. Finally, it reviews some strategies available to teachers who wish to make maximal use of the TL without denying the potential of the L1 to support foreign language learning.
Patterns of seed rain and seedling regeneration in abandoned agricultural clearings in a seasonally dry tropical forest in India
Authors: Teegalapalli Karthik , Hiremath Ankila J. , Jathanna Devcharan
Published: December 2009

Forest recovery in abandoned pastures and agricultural fields is often impeded, therefore it is important to understand the factors limiting regeneration. Patterns of seed arrival and regeneration in five abandoned agricultural clearings nested within a seasonally dry tropical forest in India were examined along five transects radiating from the forest edge into the clearings. Wind-dispersed seeds dominated the seed arrival in clearings compared with vertebrate-dispersed seeds: 5563 wind-dispersed seeds and 1094 vertebrate-dispersed seeds of 14 and 13 tree species, respectively, were recorded. Numbers of the former declined steeply with increasing distance from the forest, whereas the latter showed no evident pattern with distance. Seeds of the invasive herb,Chromolaena odorata, were abundant in clearings. Although wind-dispersed seeds greatly outnumbered vertebrate-dispersed seeds, seedlings and saplings of vertebrate-dispersed species were three times more abundant than those of wind-dispersed species, indicating distinct differences in patterns of actual and effective seed dispersal. This points to recruitment limitation, and suggests that seed arrival may not be the principal barrier to regeneration in these clearings. Nonetheless, the clearings are likely to revert to forest over time.
Forests on ultramafic-derived soils in Borneo have very depauperate termite assemblages
Authors: Jones David T. , Rahman Homathevi , Bignell David E. , Prasetyo Anggoro H.
Published: December 2009

Previous studies in Sundaland (Borneo, Sumatra, Java and Peninsular Malaysia) have shown that termite assemblages in natural forests have a characteristic structure. These typical forest assemblages contain many soil-feeding species. However, this study investigated four natural forest sites in Borneo with depauperate termite assemblages, and compared their soils with soils from four other sites that have typical termite assemblages. In contrast to the typical assemblages, the four depauperate assemblages all have low species density (<35%), low relative abundance (<30%), a virtual absence of soil-feeders, significantly fewer wood-feeders, and a near-absence of species of Rhinotermitidae, Amitermes-group, Termes-group, Pericapritermes-group and Oriensubulitermes-group. The depauperate sites are on ultramafic-derived soils and have significantly higher concentrations of calcium, magnesium, nickel, chromium, cobalt, copper and zinc compared with the non-ultramafic soils at sites with typical assemblages. In addition, soil pH at the depauperate sites is significantly higher (>pH 5.4) compared with soils at the typical sites (which are all below pH 4.7). Possible mechanisms to explain the depauperate termite assemblages on ultramafic soils include metal toxicity, high pH disrupting gut physiology, and microbial interactions with metals.
Computer-assisted assessment of free-text answers
Authors: Pérez-Marín Diana , Pascual-Nieto Ismael , Rodríguez Pilar
Published: December 2009

The automatic assessment of students’ free-text answers has recently received much attention, due to the necessity of exploring and taking advantage of new and more complex computer-based assessment methods. In this paper, a review of the state-of-art of the field is presented, focusing on the techniques that underpin these systems and their evaluation metrics. Although there is still a long way to go so as to reach the ideal system, the fact that the existing systems are already being used commercially and as a second opinion in exams such as GMAT proves the uptake of this field.