bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Rayleigh wave attenuation via annular lenses in acoustic microscopy
Authors: Bouhedja S. , Hadjoub I. , Doghmane A. , Hadjoub Z.
Published: March 2005

Using annular lenses in scanning acoustic microscopy, the attenuation coefficients for several materials were determined from the calculated V(z) interference‐free curves. The dependence of such coefficients on Rayleigh velocities as well as on operating frequencies was then investigated to establish empirical relations between these parameters. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effects of grain size on reversible and irreversible domain wall displacements in La0.7Sr0.3MnO3 perovskite
Authors: Wang Jinhui , Liu Gongqiang , Jiang Xiaolong , Du Youwei
Published: March 2005

In this work, the permeability spectra of La0.7Sr0.3MnO3 perovskite with mean grain size (D) ranging from 1200 to 45 nm have been investigated at 293 K. The spectra exhibit a typical relaxation, relating to reversible domain wall motions. The quasi‐static permeability (μe) decreases from 87 to 11 with D, while relaxation frequency fr increases from 205 kHz to 231 MHz. As the amplitude of the ac field h0 exceeds the domain wall pinning field hp, irreversible domain wall motions will be activated. The increments of permeability with increasing h0 can be explained using the Rayleigh law. With reducing D from 1200 to 140 nm, hp increases from 1.8 to 2.3 A/m and the Rayleigh constant decreasing from 2.15 × 10–1 to 4.66 × 10–2 (A/m)–1. The grain size dependence of μe and fr has been discussed related to the demagnetizing field induced by distributed air gaps between grains. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Defect states in CdSe nanocrystalline layers
Authors: Nesheva D. , Reynolds S. , Main C. , Aneva Z. , Levi Z.
Published: March 2005

Defect states and recombination processes are investigated in SiOx/nanocrystalline CdSe multilayer and composite films, and CdSe single films, using steady‐state and transient photoconductivity and thermally‐stimulated current measurements. A reduction in mobility‐lifetime product as layer thickness is reduced is assigned to increased deep defect density at the nanocrystal surface. Transient photocurrent falls rapidly at typically 0.1 µs as carriers are trapped in deep states, and then continues to fall as a power law of index close to –1. At elevated temperatures, the transient current in multilayer films falls below the steady‐state dark current. This is explained by the effect of potential barrier profiles on recombination. The density of states distribution obtained is fairly broad in multilayers and composite films while in single layer films it is noticeably peaked. Two defect bands located at 0.55 and 0.7 eV below the conduction band edge are identified, the former associated with the nanocrystal bulk and the latter with the CdSe–CdSe interface. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantum cascade lasers based on quantum dot superlattice
Authors: Dmitriev Ivan A. , Suris Robert A.
Published: March 2005

A theory of threshold characteristics of novel quantum cascade lasers with an active medium made of a regular array of quantum dots is presented. Very low threshold current density for the room‐temperature operation is predicted. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of the annealing temperature on the optical transitions of InGaAsP‐based quantum well structures investigated by photoreflectance spectroscopy
Authors: Podhorodecki A. , Kudrawiec R. , Andrzejewski J. , Misiewicz J. , Wojcik J. , Robinson B. J. , Thompson D. A. , Mascher P.
Published: March 2005

Photoreflectance (PR) and photoluminescence (PL) spectroscopies have been used to study the effect of the rapid thermal annealing (RTA) on InGaAsP‐based quantum wells (QWs) which are the active part of a laser structure tailored at 1.5 µm. In the case of PL, it has been observed that the RTA enhances PL intensity and tunes the emission wavelength of the laser structure to blue. In case of PR due to its absorption character, we were able to study QW transitions related to excited states, besides the fundamental transition observed in PL. In addition, optical transitions related to other part of the laser structure have been observed in PR. It has been shown that there exists a “critical” annealing temperature (720 °C) where the energy shift appears. We have observed a blueshift for both the ground and excited state transitions, but in the case of the ground state transitions the blueshift has been found to be bigger. The magnitude of this blueshift has been found to change linearly from 0 to ∼15 meV with the rise of temperature from 720 to 780 °C. Below 720 °C no significant change in the energy of the QW transitions is observed. In the case of PR transitions related to the other part of the laser structure, i.e., the quaternary InGaAsP barriers, it has been observed that after annealing PR features associated with these layers rather do not shift, they change only their line‐shape. Also, it has been shown that RTA does not destroy the optical quality of the samples. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Inhibitory effects of stilbenes in Sophora moorcroftiana BENTH ex BAKER on copper ion‐induced protein oxidative modification of mouse brain homogenate in vitro
Authors: Toda Shizuo , Shirataki Yoshiaki
Published: March 2005

We present the results of an in vitro investigation of the inhibitory effects of sophorastilbene A and (+)‐α‐viniferin isolated from Sophora moorcroftiana BENTH ex BAKER on copper ion‐induced protein oxidative modification. They inhibited copper‐induced protein oxidative modification. The order of these stilbenes and mannitol as a hydroxyl radical scavenger was sophorastilbene A > (+)‐α‐viniferin > mannitol. Copyright © 2005 John Wiley & Sons, Ltd.
Antiallergic and antihistaminic effect of two extracts of Capparis spinosa L. flowering buds
Authors: Trombetta Domenico , Occhiuto Francesco , Perri Daniela , Puglia Carmelo , Santagati Natale A. , Pasquale Anna De , Saija Antonella , Bonina Francesco
Published: March 2005

The antiallergic properties of two lyophilized extracts obtained from Capparis spinosa L. flowering buds (capers) by methanol extraction, carried out at room temperature (CAP‐C) or with heating at 60 °C (CAP‐H), were investigated.

The protective effects of CAP‐H and CAP‐C, orally administered (14.28 mg[sol ]kg), were evaluated against Oleaceae antigen challenge‐induced and histamine‐induced bronchospasm in anaesthetized guinea‐pigs. Furthermore, the histamine skin prick test was performed on humans, applying a gel formulation containing 2% CAP‐C (the only extract able to protect against histamine‐induced bronchospasm) on the skin for 1 h before histamine application and monitoring the erythema by reflectance spectrophotometry.

The CAP‐H showed a good protective effect against the bronchospasm induced by antigen challenge in sensitized guinea‐pigs; conversely, a significant decrease in the responsiveness to histamine was seen only in CAP‐C pretreated animals. Finally, the CAP‐C gel formulation possessed a marked inhibitory effect (46.07%) against histamine‐induced skin erythema.

These two caper extracts displayed marked antiallergic effectiveness; however, the protective effect of CAP‐H was very likely due to an indirect mechanism (for example, inhibition of mediator release from mast cells or production of arachidonic acid metabolites); conversely, CAP‐C is endowed with direct antihistaminic properties. The different mechanisms of action of CAP‐H and CAP‐C may be related to a difference in the extraction procedure and, thus, in their qualitative[sol ]quantitative chemical profile. Copyright © 2005 John Wiley & Sons, Ltd.
Radioprotection by plant products: present status and future prospects
Authors: Arora Rajesh , Gupta Damodar , Chawla Raman , Sagar Ravinder , Sharma Ashok , Kumar Raj , Prasad Jagdish , Singh Surinder , Samanta Namita , Sharma Rakesh Kumar
Published: March 2005

The development of radioprotective agents has been the subject of intense research in view of their potential for use within a radiation environment, such as space exploration, radiotherapy and even nuclear war. However, no ideal, safe synthetic radioprotectors are available to date, so the search for alternative sources, including plants, has been on going for several decades. In Ayurveda, the traditional Indian system of medicine, several plants have been used to treat free radical‐mediated ailments and, therefore, it is logical to expect that such plants may also render some protection against radiation damage. A systematic screening approach can provide leads to identifying potential new candidate drugs from plant sources, for mitigation of radiation injury. This article reviews some of the most promising plants, and their bioactive principles, that are widely used in traditional systems of medicine, and which have rendered significant radioprotection in both in vitro and in vivo model systems. Plants and their constituents with pharmacological activities that may be relevant to amelioration of radiation‐mediated damage, including antiemetic, antiinflammatory, antioxidant, cell proliferative, wound healing and haemopoietic stimulatories are also discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Bioactive triterpenoids from Vochysia pacifica interact with cyclic nucleotide phosphodiesterase isozyme PDE4
Authors: Weniger Bernard , Lobstein Annelise , Um Byung‐Hun , Vonthron‐Sénéchau Catherine , Anton Robert , Usuga Nora Jiménez , Basaran Hélène , Lugnier Claire
Published: March 2005

Several species of the genus Vochysia (Vochysiaceae) are used by traditional communities in South America to relieve ailments linked to inflammation, such as skin sores, asthma and pulmonary congestion. As the cAMP phosphodiesterase 4 isozyme (PDE4) is currently considered as an intracellular target for new antiinflammatory drugs, several constituents of Vochysia pacifica Cuatrec., an endemic tree from the Western coast of Colombia, were tested for their ability to inhibit PDE4. Purification of the methanol extract of the stem bark of this species led to the isolation of seven known triterpene derivatives: betulinic acid, sericic acid, 24‐hydroxytormentic acid, trachelosperogenin B, 24‐hydroxytormentic acid glucosyl ester, quadranoside I and niga‐ichigoside F1. One triterpene glycoside, quadranoside I, and two triterpenes, betulinic and sericic acids, exhibited mild inhibitory activity on the isolated PDE4 isozyme. Copyright © 2005 John Wiley & Sons, Ltd.
Potential biomedical properties of Pinus massoniana bark extract
Authors: Cui Yingyu , Xie Heng , Wang Jinfa
Published: March 2005

This study examined the potential biomedical properties of a bark extract from Pinus massoniana Lamb (PMBE). Its antioxidant activity, superoxide anion radical scavenging and free radical scavenging activities were examined. The antioxidant activity in a linoleic acid emulsion increased with increasing amounts of PMBE, with 100, 300 and 500 µg PMBE inhibiting 64.7%, 68.6% and 76.6% of peroxidation, respectively. Similarly, the radical scavenging activity by PMBE increased in a dose‐dependent manner, suggesting that there may be a correlation between the antioxidant and scavenging activities. In addition, the effect of PMBE on human hepatocellular carcinoma BEL‐7402 cells and normal liver L‐02 cells was investigated in vitro. PMBE appeared to inhibit selectively the growth of BEL‐7402 and slightly promoted the growth of L‐02. Taken together, the results indicate that PMBE is a natural antioxidant that could potentially be used as a food supplement or as a candidate precursor substance for new anticancer therapeutics. Copyright © 2005 John Wiley & Sons, Ltd.
Reversal of LPS‐induced central and peripheral hyperalgesia by green tea extract
Authors: Kaur Surinder , Anurag A. , Tirkey Naveen , Chopra Kanwaljit
Published: March 2005

Tea has recently attracted a great deal of attention for its beneficial health effects. Green tea polyphenols inhibit the production of arachidonic acid metabolites and leukotrienes resulting in decreased inflammatory responses. In the present study, the effect of green tea extract (GTE) on lipopolysaccharide (LPS)‐induced thermal and behavioural hyperalgesia in mice and the possible involvement of the cyclooxygenase pathway in this paradigm was evaluated. GTE (25 mg[sol ]kg, i.p.), nimesulide (2 mg[sol ]kg, i.p.) and rofecoxib (2 mg[sol ]kg, i.p.) significantly attenuated LPS‐induced thermal and behavioural hyperalgesia but per se did not modify any of the behavioural effects. Concurrent administration of a subeffective dose of GTE (10 mg[sol ]kg, i.p.) and rofecoxib (2 mg[sol ]kg, i.p.) or nimesulide (2 mg[sol ]kg, i.p.) significantly potentiated the antinociceptive effect of GTE in both LPS‐induced thermal and behavioural hyperalgesia with nimesulide showing a more pronounced enhancing effect. Thus it can be concluded that GTE attenuates LPS‐induced central and peripheral hyperalgesia by selective inhibition of cyclooxygenase‐2 enzyme. Copyright © 2005 John Wiley & Sons, Ltd.
BSSE‐corrected geometry and harmonic and anharmonic vibrational frequencies of formamide–water and formamide–formamide dimers
Authors: Bende A. , Suhai S.
Published: March 2005

The basis set superposition error (BSSE) influence in the geometry structure, interaction energies, and intermolecular harmonic and anharmonic vibrational frequencies of cyclic formamide–formamide and formamide–water dimers have been studied using different basis sets (6‐31G, 6‐31G**, 6‐31++G**, D95V, D95V**, and D95V++**). The a posteriori “counterpoise” (CP) correction scheme has been compared with the a priori “chemical Hamiltonian approach” (CHA) both at the Hartree–Fock (HF) and second‐order Møller–Plesset many‐body perturbation (MP2) levels of theory. The effect of BSSE on geometrical parameters, interaction energies, and intermolecular harmonic vibrational frequencies are discussed and compared with the existing experimental data. As expected, the BSSE‐free CP and CHA interaction energies usually show less deep minima than those obtained from the uncorrected methods at both the HF and MP2 levels. Focusing on the correlated level, the amount of BSSE in the intermolecular interaction energies is much larger than that at the HF level, and this effect is also conserved in the values of the force constants and harmonic vibrational frequencies. All these results clearly indicate the importance of the proper BSSE‐free correlation treatment with the well‐defined basis functions. At the same time, the results show a good agreement between the a priori CHA and a posteriori CP correction scheme; this agreement is remarkable in the case of large and well‐balanced basis sets. The anharmonic frequency correction values also show an important BSSE dependence, especially for hydrogen bond stretching and for low frequencies belonging to the intermolecular normal modes. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Amide I IR, VCD, and 2d IR spectra of isotope‐labeled α‐helix in liquid water: Numerical simulation studies
Authors: Choi Jun‐Ho , Hahn Seungsoo , Cho Minhaeng
Published: March 2005

Amide I infrared (IR), vibrational circular dichroism (VCD), and two‐dimensional IR (2D IR) spectra of various isotope‐labeled α‐helical polyalanines in liquid water were theoretically calculated by combining semiempirical quantum chemistry calculation, Hessian matrix reconstruction, fragmentation approximation, and molecular dynamics simulation methods. The solvation‐induced amide I frequency shift was found to be about −20 cm−1. Properly taking into account the motional narrowing effect in the ensemble averaging, we show that the simulated IR, VCD, and 2D IR spectra are quantitatively in good agreement with experimental results. Depending on the relative positions of the 13C and/or 13C18O labeled peptides in a given α‐helix, the IR absorption line shape, IR intensity distribution, positive‐negative VCD pattern, and diagonal/off‐diagonal 2D IR echo spectral features were found to change dramatically. It is shown that these different spectroscopic observations can be described in a consistent manner by using the present simulation method. We will show that the properly designed isotopomers and their IR, VCD, and 2D IR spectrum analyses can provide incisive information on the three‐dimensional polypeptide structure and dynamics. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Conformational and vibrational study of di‐n‐propyl and di‐i‐propylphosphonates by MM/QM method
Authors: Carauta Alexandre N. M. , Walkimar de M. Carneiro José , Téllez Soto Claudio A.
Published: March 2005

A conformational search by MM/QM methods was realized for the di‐n‐propyl and di‐i‐propylphosphonates. The normal mode frequencies and corresponding vibrational assignments were examined theoretically using the hybrid functional B3LYP and the 6‐31G* basis set, and were compared with the experimental spectra. It was possible to arrive at an accurate spectral assignment without the utilization of scaling factors including the region between 1,200 and 850 cm−1, which is the most complicated spectral region for the assignment. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
An emerging model of a systems agriculturalist
Authors: Valentine Ian
Published: March 2005

This paper describes the development of a conceptual model of agriculture at the Faculty of Agriculture, Hawkesbury Agricultural College, during the early 1980s. The model was a tool in a learning/researching process that was driven by the increasing complexity of problems/issues facing Australian agriculture over that period. The path took us from seeing agriculture as a science discipline‐focused, mechanistic view of agriculture to a systemic model that incorporated people as an essential component. The phases that we went through included: ‘agriculture as a production activity’, ‘agriculture as applied ecology’, ‘agriculture as a mechanical (hard) system’, and ‘agriculture as a human activity system’. Each phase was incorporated into the next so that the final model was able to be usefully used in approaching on‐farm scientific and technical issues, managerial and information flow/communication issues, and social and cultural issues. It also placed farming as an activity within the wider social and biophysical environment, which encouraged study of the impact of agriculture on the soil and water resources as well as the fate of rural communities. The model was generated through a process of action research and thus was consistent with the growing educational philosophy of the Faculty. It was a collaborative process that drew on the expertise of members of the Faculty and on a wide range of literature. Copyright © 2005 John Wiley & Sons, Ltd.
The researcher of human systems is both choreographer and chorographer
Authors: Russell David , Ison Ray
Published: March 2005

The paper will refer to research work that illustrates the researcher as chorographer (one practised in the art of systematic description of regions) and choreographer (one practised in the design of dance arrangements) of the emotions. The authors experienced this transformation when they developed and tested a conversational model of learning and change based on the biological systems work of Chilean scientist Humberto Maturana. Hawkesbury Agricultural College (which became part of the University of Western Sydney in 1989) was a fertile field for research and consulting that understood learning as change taking place in a relational space, over time, and as a consequence of engagements shaped by the participants' emotions. The use of participatory and collaborative methods to bring about change demanded an explanatory system that located the usefulness of these practices in what was understood as the biology of living systems and cognitive science. Copyright © 2005 John Wiley & Sons, Ltd.
Vortical postmodern ethnography: introducing a complexity approach to systemic social theorizing
Authors: Kuhn Lesley , Woog Robert
Published: March 2005

This paper reflects on theory evolution from the perspective of considering the role that complexity science might have in social theorizing and research. We assume that just as human society is complex, dynamic, interdependent, and with future states emerging with reference to complex histories, so too are human explanations and theories. With reference to a complexity approach to postmodern ethnography, that of vortical postmodern ethnography, we make manifest the dynamic and interdependent nature of theory building, with human actor/observers and discourse evolution. We suggest that a complexity perspective on social research and theorizing may be most valuable for its role in bringing about alternative descriptions, rather than promoting certain interventions. Copyright © 2005 John Wiley & Sons, Ltd.
Systemic development at Hawkesbury: some personal lessons from experience
Authors: Bawden Richard
Published: March 2005

One of the most significant and enduring ideas associated with the systems initiatives at Hawkesbury has been the interconnections that were made there between systemic acts of development in the ‘concrete world’ and the abstract ‘epistemic developments’ of the actors who participate in them. Each is seen to be constitutive of the other in a profoundly systemic manner, with ‘concrete events’ being both influenced by and an influence on ‘abstract ideas’. The embrace of critical experiential strategies, which themselves are regarded as essentially systemic and reflexive in nature, has been a central feature of the pedagogies, research processes, and engagement strategies that have been designed to better facilitate this interconnection. As calls for more sustainable and equitable forms of development gather momentum across the globe, and the citizenry become increasingly engaged with issues that are seen to pose significant systemic global risks, the need for collective, communicative experiential strategies in the form of systemic discourse becomes evident. Copyright © 2005 John Wiley & Sons, Ltd.
Comparative Study of Pilot Scale Rice Starch Production by an Alkaline and an Enzymatic Process
Authors: Puchongkavarin Hatairat , Varavinit Saiyavit , Bergthaller Wolfgang
Published: March 2005

Rice starch is commonly isolated by alkaline (sodium hydroxide) extraction because this process provides high yield, high purity and is low in capital costs. This process produces an highly loaded alkaline effluent that contributes significantly to general costs of wastewater treatment. The present study attempted to develop an enzymatic procedure to isolate pure rice starch and to investigate the physico‐chemical properties in comparison with that of rice starch produced by an alkaline process of comparable scale. The isolation of starch from polished rice grain was effected by application of cellulase under slightly acidic conditions in order to degrade the cellular tissue, followed by protease (Corolase 7089 or papain) under neutral conditions in order to loosen the protein bodies that are associated with starch granules. In comparison with the alkaline process, the enzyme process provided rice starch with a slightly elevated protein content, but less damaged starch. No differences were found between the two proteases used. Washing the enzyme‐isolated starch with 0.2% sodium hydroxide or 0.5% sodium dodecylsulphate (SDS) solutions further improved the purity of rice starch. The physico‐chemical properties of the enzymatically‐isolated starches were mostly comparable with starch from the alkaline process. The developed process allows to replace the alkaline process and thus eliminates critical levels of mineral load in effluents of rice starch plants.
Impact of High Hydrostatic Pressure Treatment on the Resistant Starch Content of Wheat Starch
Authors: Bauer Birgit A. , Wiehle Tanja , Knorr Dietrich
Published: March 2005

The impact of high hydrostatic pressure‐induced gelatinisation of wheat starch suspensions on its resistant starch (RS) content was examined. Optimum process parameters determined for the enhancement of RS yields in pre‐tests differed from process conditions for high RS yields after thermal gelatinisation found in literature. This indicated differing gelatinisation and RS formation processes. Nonetheless, a RS enhancement by high hydrostatic pressure treatment was possible. The highest yields of RS in pressure‐gelatinised starches were obtained after ten pressure‐annealing cycles of acid hydrolysed wheat starch suspensions (approx. 12%). In comparison to heat‐gelatinised wheat starch, the RS yields achieved after pressure‐induced gelatinisation of wheat starch were in the same range. Thus, high pressure treatment alone is not superior over thermal treatment for the production of RS in wheat starch.
Glutaraldehyde Cross‐link Analogues from Carbohydrates
Authors: Schoevaart Rob , Siebum Arjan , van Rantwijk Fred , Sheldon Roger , Kieboom Tom
Published: March 2005

The effectiveness of glutaraldehyde as protein cross‐linker is unbeaten by any cross‐linker known today. Surprisingly, no efforts have been made to improve the properties of glutaraldehyde via derivatisation. From the group of carbohydrates, periodate oxidised derivatives with cross‐linking power have been reported. We demonstrate that these are based on the 1,5‐dialdehyde structure, analogous with glutaraldehyde. Diglycolaldehyde and periodate oxidised carbohydrates containing this basic 1,5‐dialdehyde moiety show excellent cross‐linking properties. Although these cross‐linkers are less reactive than glutaraldehyde, quantitative cross‐linking is effected without undesired colouration and enzyme deactivation: effects often encountered with glutaraldehyde. These are the first results from an investigation in the use of carbohydrates for the alternative and inexpensive cross‐linking of proteins.
Organic Solvent‐free Transesterification of Various Starches with Lauric Acid Methyl Ester and Triacyl Glycerides
Authors: Aburto Jorge , Alric Isabelle , Borredon Elisabeth
Published: March 2005

This study deals with the organic solvent‐free synthesis of fatty acid esters of high‐amylose maize (amylomaize) starch by transesterification with lauric acid methyl ester using potassium laurate as catalyst. The process involves thermal pretreatment of amylomaize in order to swell the polysaccharide and increase its accessibility and reaction with the esterification reagent. The swelling degree (Q) was monitored by UV‐Vis spectrophotometry and scanning electron microscopy (SEM), whilst the formation of a complex between amylose and potassium laurate was confirmed by X‐ray diffraction and FTIR studies. The transesterification reaction was carried out at 190°C and a central composite design was used to obtain the corresponding contour plots with a second order model (y = β0 + β1 X1 + β2 X2 + β12 X1 X2 + β11 X1 X1 + β22 X2X2) and a confidence interval of 95%. The experimental design consisted of two independent variables, reaction time (2–6 h) and catalyst (2.2 – 33.8 meq catalyst per eq. glucose), and two dependent variables, the degree of substitution (DS) and the yield of the amylomaize starch ester (Y,%). Maximum transesterification of amylomaize starch (DS = 0.61) was obtained after 4:30 h at 190°C with an intermediate concentration of catalyst (18 meq per eq. glucose). Finally, the optimized results were extended to other starch sources and vegetable oils.
Starch in food – Structure, function, and application
Authors: Bergthaller W.
Published: March 2005

No abstracts.
Emergency stop simulation using a finite element model developed for large blade deflections
Authors: Ahlström Anders
Published: March 2005

Predicting the load in every possible situation is necessary in order to build safe and optimized structures. A highly dynamical case where large loads are developed is an emergency stop. Design simulation tools that can cope with the upcoming non‐linearities will be especially important as the turbines get bigger and more flexible. The model developed here uses the advanced commercial finite element system MSC.Marc, focused on non‐linear design and analysis, to predict the structural response. The aerodynamic model named AERFORCE, used to transform the wind to loads on the blades, is a blade element momentum model. A comparison is made between measured and calculated loads for the Tjæreborg wind turbine during emergency braking of the rotor. The simulation results correspond well with measured data. The conclusion is that the aeroelastic tool is likely to perform well when simulating more flexible turbines. Copyright © 2005 John Wiley & Sons, Ltd.
WAsP in the Forest
Authors: Dellwik Ebba , Landberg Lars , Jensen Niels Otto
Published: March 2005

This article compares mean wind estimates from a WAsP analysis for three forest sites and one site near a forest with measurements taken at the sites. By standard WAsP settings for forest, the mean wind speed at the sites was overestimated. Agreement between the estimates and the measurements improved significantly if displacement height and roughness length as calculated from the forest mast data were used or if a simple model estimate of roughness length and displacement height based on stand density (frontal area index) was used. The two estimates of displacement height and roughness length (mast data and simple model) did not agree well with each other. One reason for this may be that all evaluated sites are windy and that both d and z0 depend on the wind speed. All analysed forest sites are dense, in which case the influence from the roughness sublayer is limited and the effect on mean wind speeds from this layer could not be evaluated. Copyright © 2005 John Wiley & Sons, Ltd.
The Design of closed loop controllers for wind turbines
Authors: Bossanyi E. A.
Published: March 2005

This article reviews the design of algorithms for wind turbine pitch control and also for generator torque control in the case of variable speed turbines. Some recent and possible future developments are discussed. Although pitch control is used primarily to limit power in high winds, it also has a significant effect on various loads. Particularly as turbines become larger, there is increasing interest in designing controllers to mitigate loads as far as possible. Torque control in variable speed turbines is used primarily to maximize energy capture below rated wind speed and to limit the torque above rated. Once again there are opportunities for designing these controllers so as to mitigate certain loads. In addition to improving the design of the control algorithms, it is also possible to use additional sensors to help the controller to achieve its objectives more effectively. The use of additional actuators in the form of individual pitch controllers for each blade is also discussed. It is important to be able to quantify the benefits of any new controller. Although computer simulations are useful, field trials are also vital. The variability of the real wind means that particular care is needed in the design of the trials. Copyright © 2001 John Wiley & Sons, Ltd.
Predicting participation and outcomes in out‐of‐school activities: Similarities and differences across social ecologies
Authors: Simpkins Sandra D. , Ripke Marika , Huston Aletha C. , Eccles Jacquelynne S.
Published: March 2005

Children's participation in organized out‐of‐school‐time activities and the outcomes associated with those activities vary according to family social ecology and child characteristics.
Recruitment and retention strategies for out‐of‐school‐time programs
Authors: Lauver Sherri C. , Little Priscilla M.D.
Published: March 2005

Out‐of‐school‐time programs can increase youth participation using a set of promising strategies and a school and community‐wide commitment to implement them.
Present and accounted for: Measuring attendance in out‐of‐school‐time programs
Authors: Fiester Leila M. , Simpkins Sandra D. , Bouffard Suzanne M.
Published: March 2005

Methods for collecting attendance data in out‐of‐school‐time programs depend on program goals, characteristics, and design.
The ABCs of engagement in out‐of‐school‐time programs
Authors: Bartko W. Todd
Published: March 2005

How do out‐of‐school‐time programs get from attendance to active engagement? School researchers propose that engagement is composed of three “ABC” components, affect, behavior, and cognition, which can also be applied to out‐of‐school‐time programs.
Activities, engagement, and emotion in after‐school programs (and elsewhere)
Authors: Vandell Deborah Lowe , Shernoff David J. , Pierce Kim M. , Bolt Daniel M. , Dadisman Kimberly , Brown B. Bradford
Published: March 2005

Experience sampling methodology was used to measure engagement during the after‐school hours. Experiences that combined high levels of intrinsic motivation with concerted effort and enjoyment were more likely at after‐school programs than elsewhere.
The burden of neuropathic pain: results from a cross‐sectional survey
Authors: McDermott Anne M. , Toelle Thomas R. , Rowbotham David J. , Schaefer Caroline P. , Dukes Ellen M.
Published: March 2005

Background There are few published data on the treatment patterns and burden of neuropathic pain. We have investigated this in a large, observational, cross‐sectional survey.

Methods We surveyed 602 patients with neuropathic pain recruited from general practitioners in six European countries. Physicians recorded demographic and treatment information, including prescription medications. Patients completed Brief Pain Inventory (BPI) severity and interference questions, the EuroQol (EQ‐5D), and questions about their productivity, non‐prescription treatments, and frequency of physician visits. The BPI Pain Severity score (range: 0–10) is the mean of worst, least, average, and current pain ratings, with scores of 4–6 and 7–10 considered moderate and severe, respectively. We evaluated the impact of pain severity on functioning using analysis of variance models and χ2 tests.

Results Mean (SD) age was 62.9 (14.4) years (50% female). Most patients reported moderate (54%) or severe (25%) pain. Nearly all patients (93%) were prescribed medications for their neuropathic pain: analgesics (71%); anti‐epileptics (51%); antidepressants (29%); sedatives/hypnotics (15%). Seventy‐six percent visited their physician at least once in the past month. Employment status was affected in 43% of patients; those employed missed a mean (SD) of 5.5 (9.8) workdays during the past month. Pain severity was associated significantly (P < 0.001) with poorer EQ‐5D scores (mild = 0.67, moderate = 0.46, severe = 0.16), greater disruption of employment status (mild = 24%, moderate = 48%, severe = 54%), and more frequent physician visits (% with one or more visits: mild = 66%, moderate = 79%, severe = 83%).

Conclusions Patients with neuropathic pain visit their physician frequently and report substantial pain that interferes with daily functioning despite receiving treatment.
Quantitative sensory testing: a comprehensive protocol for clinical trials
Authors: Rolke R. , Magerl W. , Campbell K. Andrews , Schalber C. , Caspari S. , Birklein F. , Treede R.‐D.
Published: March 2005

We have compiled a comprehensive QST protocol as part of the German Research Network on Neuropathic Pain (DFNS) using well established tests for nearly all aspects of somatosensation. This protocol encompasses thermal as well as mechanical testing procedures. Our rationale was to test for patterns of sensory loss (small and large nerve fiber functions) or gain (hyperalgesia, allodynia, hyperpathia), and to assess both cutaneous and deep pain sensitivity. The practicality of the QST protocol was tested in 18 healthy subjects, 21–58 years, half of them female. All subjects were tested bilaterally over face, hand and foot. We determined thermal detection and pain thresholds including a test for the presence of paradoxical heat sensations, mechanical detection thresholds to von Frey filaments and a 64‐Hz tuning fork, mechanical pain thresholds to pinprick stimuli and blunt pressure, stimulus‐response‐functions for pinprick and dynamic mechanical allodynia (pain to light touch), and pain summation (wind‐up ratio) using repetitive pinprick stimulation.

The full protocol took 27 − 2.3 min per test area. The majority of QST parameters were normally distributed only after logarithmic transformation (secondary normalization) except for the frequency of paradoxical heat sensations, cold and heat pain thresholds, and for vibration detection thresholds. Thresholds were usually lowest over face, followed by hand, and then foot. Only thermal pain thresholds, wind‐up ratio and vibration detection thresholds were not significantly dependent on the body region. There was no significant right‐to‐left difference for any of the QST parameters; left‐to‐right correlation coefficients ranged between 0.78 and 0.97, thus explaining between 61% and 94% of the variance. This study has shown that a complete somatosensory profile of one affected area and one unaffected control area, which will be necessary to characterize patients with a variety of diseases, can be obtained within 1 h. Case examples of selected patients illustrate the value of z‐transformed QST data for an easy survey of individual symptom profiles.
Spinal cord stimulation for complex regional pain syndrome: A systematic review of the clinical and cost‐effectiveness literature and assessment of prognostic factors
Authors: Taylor Rod S. , Van Buyten Jean‐Pierre , Buchser Eric
Published: March 2005

Objective To review the clinical and cost‐effectiveness of spinal cord stimulation (SCS) in the management of patients with complex regional pain syndrome (CRPS) and identify the potential predictors of SCS outcome.

Design Systematic review of the literature and meta‐regression.

Methods Electronic databases were searched for controlled and uncontrolled studies and economic evaluations relating to the use of SCS in patients with either CRPS type I or II.

Results One randomised controlled trial, 25 case series and one cost‐effectiveness study were included. In the randomised controlled trial in type I CRPS patients, SCS therapy lead to a reduction in pain intensity at 24 months of follow‐up (mean change in VAS score −2.0), whereas pain was unchanged in the control group (mean change in VAS score 0.0) (p < 0.001). In the case series studies, 67% (95% CI 51%, 84%) of type I and type II CRPS patients implanted with SCS reported pain relief of at least 50% over a median follow‐up period of 33 months. No statistically significant predictors of pain relief with SCS were observed in multivariate meta‐regression analysis across studies. An economic analysis based on the randomised controlled trial showed a lifetime cost saving of approximately €58,470 (US$60,800) with SCS plus physical therapy compared with physical therapy alone. The mean cost per quality‐adjusted life‐year at 12‐month follow‐up was €22,580 (US$23,480).

Conclusions SCS appears to be an effective therapy in the management of patients with CRPS type I (Level A evidence) and type II (Level D evidence). Moreover, there is evidence to demonstrate that SCS is a cost‐effective treatment for CRPS type I.
Chronic pain and reduced work effectiveness: The hidden cost to Australian employers
Authors: van Leeuwen Marina T. , Blyth Fiona M. , March Lyn M. , Nicholas Michael K. , Cousins Michael J.
Published: March 2005

Cost estimates of the impact of chronic pain on work have largely focussed on absenteeism, excluding the hidden contribution of reduced work effectiveness to lost productivity. This paper aims to estimate the cost of lost productivity due to chronic pain in Australia, not only in terms of absenteeism but also reduced work effectiveness. Data on chronic pain in Australia and its impact on work were obtained from the 1997 New South Wales Health Survey (n = 17,543) and the Northern Sydney Area Pain Study (n = 2,092), both of which were population‐based and used random‐digit dialling sampling methods. This was combined with relevant Australian population and labour force data obtained from the Australian Bureau of Statistics. From this we estimated annual lost productivity costs arising from both chronic pain‐related days absent and ‘reduced‐effectiveness workdays'. There were estimated to be 9.9 million workdays absent due to chronic pain annually in Australia, equating to a cost of AUD 1.4 billion per annum. Under the assumption that reduced‐effectiveness workdays affect productivity costs in the same way as lost work days, the total number of lost workday equivalents was 36.5 million, with the total annual cost of lost productivity due to chronic pain estimated as AUD 5.1 billion per annum. In conclusion, while the impact of reduced work effectiveness on days worked with pain on productivity is uncertain, it has the potential to account for the majority of lost productivity costs associated with chronic pain. Interventions which target working despite pain have the potential to significantly reduce lost productivity costs due to chronic pain.
An adenosine A2A receptor agonist reduces interleukin‐8 expression and glycosaminoglycan loss following septic arthrosis
Authors: Cohen Steven B. , Leo Brian M. , Baer Geoffrey S. , Turner Maria A. , Beck Gina , Diduch David R.
Published: March 2005

The purpose of this study was to determine whether an adenosine A2A receptor agonist (ATL146e) might augment the current treatment regimen of antibiotics plus irrigation and debridement to prevent the arthritic effects associated with joint sepsis. Staphylococcus aureus bacteria were injected into knees of rabbits, which were divided into 4 treatment groups (12 rabbits per group): no treatment, ATL146e only, antibiotics only, or antibiotics plus ATL146e. Analysis at days 1, 3, and 7 consisted of gross joint appearance, synovial fluid, serum, histologic, immunohistochemical, and biochemical analysis.

Synovial fluid cultures at day 7 were negative in all antibiotic and antibiotic plus ATL146e treated knees indicating clearance of bacteria. Average WBC counts from synovial fluid aspirates significantly decreased with treatment of antibiotics alone and antibiotics plus ATL146e. Treatment with antibiotics plus ATL146e significantly decreased the Interleukin‐8 content when compared to other treatment groups (p < 0.001) indicating inflammatory response suppression. Histologic grading resulted in notably improved scores in the antibiotics plus ATL146e group compared to other treatment groups (p < 0.001). Glycosaminoglycan assay values were significantly greater in the ATL146e plus antibiotics group compared to the untreated control group (p < 0.04) indicating chondroprotection.

The results of this study indicate that administration of an adenosine A2A agonist in combination with antibiotic therapy diminishes joint WBC chemotaxis and reduces joint inflammation, while not compromising the clearance of intraarticular bacteria in a rabbit model. Early bacterial clearance with modulation of the inflammatory response appears to prevent the early degradative effects of joint sepsis. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Altered loading during walking and sit‐to‐stand is affected by quadriceps weakness after total knee arthroplasty
Authors: Mizner Ryan L. , Snyder‐Mackler Lynn
Published: March 2005

Purpose: Total knee arthroplasty (TKA) successfully reduces pain, but has not achieved comparable improvements in function. We hypothesized that quadriceps strength affects performance by altering loading and movement patterns during functional tasks.

Methods: Fourteen subjects with isolated, unilateral TKA were tested three months after surgery. Quadriceps strength was assessed isometrically and kinematics, kinetics, and EMG were collected during level walking and sit‐to‐stand (STS). Function was assessed using the timed up and go test (TUG), stair climbing test (SCT), and the 6 min walk test (6MW).

Results: Functional performance was significantly related to the quadriceps strength of both legs, but was more strongly related to the uninvolved strength (involved rho = –0.43 with TUG; –0.65 with SCT; 0.64 with 6MW) (uninvolved rho = –0.63 with TUG; –0.68 with SCT; 0.77 with 6MW). During STS, subjects shifted weight away from the operated limb (p <0.01). Quadriceps muscle activity and the extension moments at the knee and hip were smaller in the involved compared to the uninvolved (p <0.05). The amount of asymmetry in knee excursion during weight acceptance in gait, the asymmetry in weight bearing from sit‐to‐stand, and the uninvolved hip extension moment during STS were related to the amount of asymmetry in quadriceps strength (rho > 0.56, p < 0.05).

Conclusions: Quadriceps weakness in patients with TKA has a substantial impact on the movement patterns and performance of the knee during functionally important tasks.

© 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
IMAGINING HOME: MIGRATION AND THE IGBO VILLAGE IN COLONIAL NIGERIA
Authors: VAN DEN BERSSELAAR DMITRI
Published: March 2005

Current attempts at understanding ‘neo-traditionalism’ in Africa stress the limits of invention and warn against according too great a role to colonial intervention. Colonialism nevertheless remains important to our understanding of specific neo-traditionalisms, not only because it forced particular social and economic changes on to African communities but also because of the way that Africans appropriated colonial claims. This article explores how Igbo villages were re-imagined as a result of the complex relations between Igbo ‘sons abroad’ and their hometowns during the colonial period. Appropriating the colonizers' claims to bring ‘progress’, migrants attempted to achieve status and influence in the villages from which they had migrated. These strategies shaped not only how migrants perceived their connection with their village, but also perceptions of the village itself: it came to include the ‘sons abroad’ in a diasporic public sphere that was not in itself geographically defined, but existed through reference to the village.
SPACE, POWER AND HEALING IN EQUATORIAL AFRICA Colonial Rule and Crisis in Equatorial Africa: Southern Gabon ca. 1850–1940. CHRISTOPHER GRAY. Rochester NY: University of Rochester Press, 2002. Pp. xxii+275. $65 (ISBN 1-58046-048-8).
Authors: BERNAULT FLORENCE
Published: March 2005

THE Anglophone literature has conceptualized the history of the African ‘space’ through two major approaches. Fine-grained reconstructions of land disputes have helped to illuminate colonial changes in the political and economic control over residential and productive units, and to assess the local (im)possibilities for Africans of accumulating landed property and/or penetrating the new plantation and market economy. More recently, environmental studies have encouraged historians to uncover how fundamental alterations in the relationships between communities and their physical environment have been shaping ancient and recent struggles for identities and socio-political resources. Meanwhile, renewed attention to cognitive notions of space by anthropologists on the one hand, and literary critics on the other, has delineated deep structuring principles in the ideological construction of space among Africans and colonizers. Few historians have followed through, however, and historicized such imaginaries. Among those who have done so, and have traced people's conceptual, commemorative and moral visions of land, fewer still have ventured beyond the boundaries of specific locales and societies. By reconstructing a longue durée history of the disruptions in both the physical and cognitive spaces of the Gabonese rainforest, Chris Gray's book stands as a major attempt to bridge these gaps.