bluuebunny/crossref_metadata_2025 huggingface dataset:
Full‐scale dynamic testing and analysis of a reservoir intake tower
Authors: Daniell W. E. , Taylor C. A.
Published: April 2007

Dynamic tests were conducted on a 50 m high intake tower at Wimbleball dam in the U.K. The results were compared against predictions from a corresponding numerical model. The aim of this work was to validate the assumption that the compressibility of the reservoir water is not a significant factor in the seismic analysis of intake towers.

Three sets of tests were conducted on different occasions with different water levels in the reservoir. In the first two tests, modal characteristics of the tower were determined from the measured responses under ambient, hammer and human excitation. These results were used in planning the final set of tests where rotating eccentric mass exciters were used to vibrate the tower. Structural accelerations and hydrodynamic pressures were measured over the height of the tower for three important bending modes of vibration.

The finite element method was used to develop a numerical model for Wimbleball tower. The tower was discretized with traditional solid elements and the reservoir with incompressible fluid elements. This model was analysed to predict the modal characteristics and harmonic responses of the tower and reservoir under the various conditions imposed during the dynamic tests.

Theoretical predictions of the tower's accelerations and hydrodynamic pressures in the reservoir were compared against the test results. Excellent agreement was found for the natural frequencies and mode shapes while predictions of the harmonic responses were only fair.

The observed responses of the tower and reservoir support the assumption that reservoir compressibility is not a significant factor in the seismic analysis of towers of this size.
Evaluation of an active variable‐damping structure
Authors: Polak E. , Meeker G. , Yamada K. , Kurata N.
Published: April 2007

We present a numerical evaluation of the potential improvements in seismic disturbance rejection to be obtained by using active variable damping control in a structure. Using the responses to seismic excitation of an optimally controlled variable structure and of a minimax‐optimal designed fixed structure, we obtain an upper bound on the achievable performance and a lower bound on the acceptable performance of a control system for a variable‐damping structure. Both of these bounds are relative to an energy‐function criterion. Our numerical experiments lead to the following conclusions:

The gap between the upper and lower bounds is rather small, which makes designing a feedback law, that results in performance superior to that of a minimax‐optimal designed structure, very difficult. The best choice for a feedback law appears to be continuous moving horizon control, whose implementation requires ground motion prediction up to 0.2 sec ahead, possibly using sensors located a small distance away from the site.

A minimax‐optimal designed structure gives very good seismic disturbance suppression, not only for the earthquakes used in its design, but also for other earthquakes of similar intensity. Controlled variable structures are likely to offer advantages when earthquakes are moderate to severe, particularly at sites, such as landfills and dry lake beds, where resonances can be expected, but the resonance frequency cannot be estimated in advance.
An experimental study on active control of in‐plane cable vibration by axial support motion
Authors: Fujino Yozo , Susumpow Thumanoon
Published: April 2007

Active control of slightly sagged cables using the axial motion at the cable support is studied experimentally and analytically. Non‐linear modal equations of a cable are presented, and two control schemes are identified, i.e. active stiffness control and active sag‐induced force control. In this study, emphasis is placed on the active sag‐induced force control. Additional damping is analytically expressed when a velocity feedback control is used. Although the active sag‐induced force control can be applicable only for in‐plane symmetric modes, it is shown that it is very efficient for the first mode. An experiment is conducted using a scaled cable model of 2 m length. First, it is shown by the experiment that the analytical model can predict well the non‐linear cable motion. Next, sag‐induced force control is examined using free vibration and harmonic excitations. The results agree well with the analytical predictions and confirm that additional damping can be obtained efficiently from the axial support motion.
Energy dissipation behaviour of shear panels made of low yield steel
Authors: Nakashima Masayoshi , Iwai Satoshi , Iwata Mamoru , Takeuchi Toru , Konomi Shinzo , Akazawa Takashi , Saburi Kazuhiro
Published: April 2007

This paper presents the results of a pilot test conducted for evaluating the energy dissipation behaviour of shear panels made of low yield steel whose 0.2 per cent offset yield stress is 120 MPa. A total of six full‐scale shear panels were tested with the loading condition, stiffener spacing, and magnitude of axial force as test variables. The shear panels tested yielded at a shear force that is approximately 1/3 of the yield shear force of equivalent shear panels made of common mild steel. Shear panels with proper stiffener arrangement exhibited stable hysteresis, thus ensuring large energy dissipation capacity. Sufficient strain hardening was observed in the shear panels tested, with their energy dissipation capacity about 1.5 times larger than that of an equivalent linear‐elastic and perfect‐plastic system. Plate buckling did not lead the shear panels to immediate degradation in their energy dissipation capacity. Post‐buckling resistance was found to be a subject that requires further studies for quantifying the performance of shear panels made of low yield stress steel as hysteretic dampers.
Dynamic modelling and design of earthquake‐resistant walls
Authors: Linde Peter , Bachmann Hugo
Published: April 2007

In multi‐storey structures reinforced concrete structural walls may provide significant resistance against earthquake action. For a check of the global dynamic performance of such walls, there is a need for efficient numerical models. This paper presents a newly developed model used for the simulation of the dynamic behaviour of earthquake‐resistant multistorey walls. The model, which is based on an earlier proposal by Kabeyasawa et al. consists of non‐linear springs connected by rigid beams. The model properties are derived based on elastic theory for cantilever walls as well as nonlinear physical behaviour of wall cross‐sections supplemented by empirical data. The model behaviour is checked against experimental results and then the model is applied in an example comprising a non‐linear time history analysis of an eight‐storey wall structure. Based on the findings from the numerical model, improved capacity design rules for walls are proposed.
Observations on non‐linear dynamic characteristics of suspension bridges
Authors: Brownjohn J. M. W.
Published: April 2007

For most forms of loading static and dynamic response of a suspension bridge is modelled adequately by linear analysis. By examining the two principal non‐linearities of inclined and vertical hanger suspension bridges the limitations of linear analyses are shown. The inclined hanger configuration is shown to be the more strongly non‐linear. Some examples are given for simplified planar analyses of this type of bridge to large amplitude vehicular, random, sinusoidal and propagating earthquake excitation, showing that the effect only becomes significant when deflections approach the extent of cable sag due to cable elasticity.
Influence of the spatial distribution of energy‐dissipating bracing elements on the seismic response of multistorey frames
Authors: Ruiz Sonia E. , Urrego Olga E. , Silva Francisco L.
Published: April 2007

Several reinforced concrete frames with different dissipator distributions, and a conventional moment‐resisting frame, are compared in order to select the best dissipator distribution from the point of view of seismic response and structural design. The structures with dissipators are designed according to a criterion proposed in the present paper. Each frame is excited with a set of eleven simulated accelerograms. The choice of the best dissipation distribution is based mainly on the differences between the mean of the maximum overturning moments developed at the base of the frames and between the weights of steel reinforcement and concrete resulting from the structural design of each frame. A comparison of initial construction costs of a building with dissipators and a conventional building shows that the former is 3·5 per cent more expensive.
Critical earthquake input power spectral density function models for engineering structures
Authors: Manohar C. S. , Sarkar Abhijit
Published: April 2007

The problem of determining optimal power spectral density models for earthquake excitation which satisfy constraints on total average power, zero crossing rate and which produce the highest response variance in a given linear system is considered. The solution to this problem is obtained using linear programming methods. The resulting solutions are shown to display a highly deterministic structure and, therefore, fail to capture the stochastic nature of the input. A modification to the definition of critical excitation is proposed which takes into account the entropy rate as a measure of uncertainty in the earthquake loads. The resulting problem is solved using calculus of variations and also within linear programming framework. Illustrative examples on specifying seismic inputs for a nuclear power plant and a tall earth dam are considered and the resulting solutions are shown to be realistic.
Willingness‐to‐pay for a statistical life in the times of a pandemic
Authors: Gyrd‐Hansen Dorte , Halvorsen Peder Andreas , Kristiansen Ivar Sønbø
Published: April 2007

A contingent valuation was performed based on cross‐sectional web‐based interviews of individuals aged 16–82 years of age presenting a scenario of influenza pandemic. The mean WTP for a course of Tamiflu was NOK 1034 (median NOK 250). Anxious individuals perceived the pandemic mortality risk to be higher than others, but also perceived the benefit of Tamiflu as greater. They also expressed a higher WTP for Tamiflu, but the implied VOSL was less than for other respondents. The results suggest that fear and anxiety distort decision making under uncertainty and decrease focus on the perceived risk reduction. Copyright © 2007 John Wiley & Sons, Ltd.
Information systems support for CNC machinists: Evaluating the impact of information technology at the shop floor
Authors: Butcher Tim , Greenough Richard M.
Published: April 2007

As information technology (IT) capabilities increase, manufacturing businesses are realigning their information systems infrastructure to remain competitive. This has resulted in substantial increases in IT use in technical areas of the business. Nevertheless, conventional paper‐based information systems are still common at the shop floor. Hence, manufacturers need to understand whether there is benefit in extending IT functionality to the shop floor. By evaluating the impact of hypermedia information systems on the independent decision‐making and communication capabilities of computer numerical control (CNC) machinists, this research aims to identify the shop floor benefits of replacing existing paper‐based systems with this relatively new technology in this context. The research findings have wide‐ranging implications for further research into the strategic implementation of shop floor IT and for future work structures in the metal cutting industry. © 2007 Wiley Periodicals, Inc. Hum Factors Man 17: 299–314, 2007.
Human error driving the development of a checklist for foreign material exclusion in the nuclear industry
Authors: Kenger Patrik , Karlsson Anders
Published: April 2007

In this article we describe an approach to develop a checklist for foreign material exclusion. Foreign material is material that should not be part of, or supplied with, the product because it can affect the performance of, for example, nuclear fuel rods of nuclear plants. The research itself was initiated by the presence of different types of human errors. Specifically in the nuclear industry, where there is zero tolerance for errors, work to continuously improve safety and quality is of major importance. Our approach should support such work. As a theoretical base, we have considered team errors as well as individual errors. The suggested practical approach is based on foreign materials that originate in or are introduced into a product or a process. © 2007 Wiley Periodicals, Inc. Hum Factors Man 17: 283–298, 2007.
Antiresorptive agents and osteoclast apoptosis
Authors: Stern Paula H.
Published: April 2007

Antiresorptive agents have proven to be effective therapies for the treatment of bone diseases associated with excessive osteoclast activity. Decreased osteoclast formation, inhibition of osteoclast actions, and reduced osteoclast survival represent mechanisms by which antiresorptive agents could act. The goals of this article are to present the evidence that antiresorptive agents can decrease osteoclast survival through apoptosis, to review the mechanisms by which they are thought to activate the apoptotic process, and to consider whether the actions on apoptosis fully account for the antiresorptive effects. As background, the apoptotic process will be briefly summarized together with the evidence that factors that promote osteoclast survival affect steps in the process. Following this, therapeutic agents that are both antiresorptive and can stimulate osteoclast apoptosis will be discussed. Other bone therapeutic agents that are either antiresorptive or apoptotic, but not both, will be described. Finally, newer antiresorptive compounds that elicit apoptosis and could represent potential therapeutic agents will be noted. J. Cell. Biochem. 101:1087–1096, 2007. © 2007 Wiley‐Liss, Inc.
Can a physics‐based, all‐atom potential find a protein's native structure among misfolded structures? I. Large scale AMBER benchmarking
Authors: Wroblewska Liliana , Skolnick Jeffrey
Published: April 2007

Recent work has shown that physics‐based, all‐atom energy functions (AMBER, CHARMM, OPLS‐AA) and local minimization, when used in scoring, are able to discriminate among native and decoy structures. Yet, there have been only few instances reported of the successful use of physics based potentials in the actual refinement of protein models from a starting conformation to one that ends in structures, which are closer to the native state. An energy function that has a global minimum energy in the protein's native state and a good correlation between energy and native‐likeness should be able to drive model structures closer to their native structure during a conformational search. Here, the possible reasons for the discrepancy between the scoring and refinement results for the case of AMBER potential are examined. When the conformational search via molecular dynamics is driven by the AMBER potential for a large set of 150 nonhomologous proteins and their associated decoys, often the native minimum does not appear to be the lowest free energy state. Ways of correcting the potential function in order to make it more suitable for protein model refinement are proposed. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007
Poly(vinyl alcohol) (PVA)/sulfonated polyhedral oligosilsesquioxane (sPOSS) hybrid membranes for direct methanol fuel cell applications
Authors: Chang Young‐Wook , Wang Erdong , Shin Geumsig , Han Jung‐Eun , Mather Patrick T.
Published: April 2007

Organic/inorganic hybrid membranes based on poly(vinyl alcohol) (PVA) and sulfonated polyhedral oligosilsesquioxane (sPOSS), crosslinked by ethylenediaminetetraacetic dianhydride (EDTAD), were prepared as candidate materials for proton exchange membranes in direct methanel fuel cell (DMFC) applications. Fourier transform infrared (FT‐IR) spectroscopy and ion exchange capacity measurements for the prepared networks clearly revealed sPOSS incorporation. We found that proton conductivity increased and methanol permeability decreased with increasing sPOSS content in the hybrid membrane. In particular, our hybrid membranes demonstrated proton conductivities as high as 0.042 S/cm, which is comparable to that of Nafion™, while exhibiting two orders of magnitude lower methanol permeability as compared to Nafion™. We postulate that the polar sulfonic acid groups of the incorporated sPOSS cages assemble to provide ion conduction paths while the hydrophobic portions of the same sPOSS cages combine to form a barrier to methanol permeation with improved thermal stability of the hybrid membrane. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and characterization of a novel polytriazole resin with low‐temperature curing character
Authors: Tian Jianjun , Wan Liqiang , Huang Jianzhi , Hu Yanhong , Huang Farong , Du Lei
Published: April 2007

A novel low‐temperature curing polytriazole resin was prepared from a triazide and a tetraalkyne and characterized. The resin can be cured at 70°C. The glass transition temperature Tg and thermal decomposition temperature Td5 of the cured resin with the molar ratio of azide to alkyne group [A]/[B] = 1.0:1.0 reached 324 and 355°C, respectively. The study on the curing kinetics of the resin shows that the apparent activation energy of the curing reaction is 93 kJ mol−1. The flexural strength of the cured resin reached 137.6 MPa at room temperature and 102.6 MPa at 185°C. Copyright © 2007 John Wiley & Sons, Ltd.
Altered cryptal expression of luminal potassium (BK) channels in ulcerative colitis
Authors: Sandle GI , Perry MD , Mathialahan T , Linley JE , Robinson P , Hunter M , MacLennan KA
Published: April 2007

Decreased sodium (Na+), chloride (Cl−), and water absorption, and increased potassium (K+) secretion, contribute to the pathogenesis of diarrhoea in ulcerative colitis. The cellular abnormalities underlying decreased Na+ and Cl− absorption are becoming clearer, but the mechanism of increased K+ secretion is unknown. Human colon is normally a K+ secretory epithelium, making it likely that K+ channels are expressed in the luminal (apical) membrane. Based on the assumption that these K+ channels resembled the high conductance luminal K+ (BK) channels previously identified in rat colon, we used molecular and patch clamp recording techniques to evaluate BK channel expression in normal and inflamed human colon, and the distribution and characteristics of these channels in normal colon. In normal colon, BK channel α‐subunit protein was immunolocalized to surface cells and upper crypt cells. By contrast, in ulcerative colitis, although BK channel α‐subunit protein expression was unchanged in surface cells, it extended along the entire crypt irrespective of whether the disease was active or quiescent. BK channel α‐subunit protein and mRNA expression (evaluated by western blotting and real‐time PCR, respectively) were similar in the normal ascending and sigmoid colon. Of the four possible β‐subunits (β1–4), the β1‐ and β3‐subunits were dominant. Voltage‐dependent, barium‐inhibitable, luminal K+ channels with a unitary conductance of 214 pS were identified at low abundance in the luminal membrane of surface cells around the openings of sigmoid colonic crypts. We conclude that increased faecal K+ losses in ulcerative colitis, and possibly other diseases associated with altered colonic K+ transport, may reflect wider expression of luminal BK channels along the crypt axis. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The skimmiwallinols—minor components of the epicuticular wax of Cocos nucifera
Authors: Escalante‐Erosa Fabiola , Arvízu‐Méndez Gloria E. , Peña‐Rodríguez Luis M.
Published: April 2007

Four new skimmiwallinol derivatives, isoskimmiwallinol acetate (4), skimmiwallinol acetate (5), isoskimmiwallinone (6) and skimmiwallinone (7), along with the previously isolated major components isoskimmiwallin (2) and skimmiwallin (3), have been found in the wax extract of pinnae from Cocos nucifera. Metabolites 4 and 5 were obtained as an inseparable mixture and identified by analysis of spectroscopic data and chemical correlation with 2 and 3, respectively. Metabolites 6 and 7 were identified by GC co‐injection with the corresponding synthetic derivatives prepared from 4 and 5. Copyright © 2007 John Wiley & Sons, Ltd.
Steady‐state analysis of emulsion polymerisation in a seeded, continuous stirred‐ tank reactor
Authors: Poehlein Gary W. , Dubner Walter , Lee Hsueh‐Chi
Published: April 2007

A steady‐state model is presented for emulsion polymerisation in a continuous stirredtank reactor (CSTR) which is fed with a narrow particle‐size seed latex. The rather general kinetic model of Ugelstad et al 1,5 for monodisperse particles is applied to the polymerisation among latexes of broad particle size distribution in a CSTR.

The model accounts for free radical absorption and desorption from the latex particles, for termination in the particles and the water phase, and for polymerisation within the particles. Results presented include the latex particle size distributions in the CSTR effluent stream and the number of free radicals per particle, averaged over these size distributions.
The glass transition and the glassy state in isotropic and liquid crystalline polymers
Authors: Rehage Günther , Frenzel Jürgen
Published: April 2007

PVT‐measurements on atactic polystyrene shows that the Ehrenfest equations, which describe a thermodynamic transformation of the second order, are not applicable for the glass transition. The introduction of one internal ordering parameter ζ in addition to the conventional variables T and P, is sufficient to describe the behaviour in case of atactic PS in the isotropic glassy state. The usually observed way dependences in the glassy state can be explained by the concept of ordering parameters.

In recent years liquid crystalline side chain polymers were developed. The liquid crystalline phases of these polymers can be supercooled and frozen‐in like isotropic liquids. As the nematic or smectic liquid crystalline structure freezes‐in, and can be conserved by this process, glasses with anisotropic properties are obtained. These glasses show e.g. a high optical birefringence.

The glass transition of the liquid crystalline polymers can only be described by the assumption of at least two parameters ζi. Therefore the Ehrenfest equations are not applicable for the glass transition of isotropic as well as anisotropic glasses.
Epoxy systems with improved water resistance, and the non‐fickian behaviour of epoxy systems during water ageing
Authors: Johncock P. , Tudgey G. F.
Published: April 2007

N,N‐Bis (2, 3‐epoxypropyl) aniline and 4,4′‐methylenebis‐[N,N‐bis (2,3‐epoxypropyl) aniline] containing bromo, chloro, trifluoromethyl or polyfluoroalkoxy substituents were synthesised and cured with aromatic diamines in order to investigate the effect of substituted halogen on water absorption. Significant improvements were achieved: thus use of 4,4′‐methylenebis‐[N, N‐bis (2, 3‐epoxypropyl)‐3, 5‐dichloroaniline] and 4,4′‐methylenebis‐[N,N‐bis (2,3‐epoxypropyl)‐3‐(trifluoromethyl) aniline] instead of 4,4′‐methylenebis‐[N,N‐bis (2,3‐epoxypropyl) aniline] reduced the water absorption by about a half. Departures from Fickian behaviour were observed during water immersion ageing at room temperature and were a general feature of the epoxy systems examined. Plots of water absorption against the Fickian parameter (√t/d) usually showed at least mild sigmoid character and were not independent of specimen thickness. Further, slow continued uptake of water occurred during long‐term ageing, and evidence is provided that the associated network distortions are reversible.
Some recent developments with light‐sensitive resin systems
Authors: Irving Edward , Stark B. Peter
Published: April 2007

Two general approaches in the development of light‐crosslinkable resin systems with very good end‐properties are summarised: (1) photoinitiation of the cationic polymerisation of epoxy resins, and (2)‘dual‐functionality’ epoxies. The major known photoinitiators for epoxy cure are surveyed, and in particular various sulphonium salt types. Recent observations on sulphoxonium salts of different kinds, as new catalysts for the photo‐cure of epoxy resins, are described.
Fortifiers for epoxy‐amine systems
Authors: McLean Paul D. , Scott Robert F. , Garton Andrew
Published: April 2007

The use of a range of additives is described which can increase the strength and modulus of cured epoxy‐amine systems by up to 70 per cent. These additives, called ‘Epoxy Fortifiers’, are liquids or low melting point solids which are incorporated into the resincuring agent mixture, prior to curing, at loadings of 10–40 parts per hundred of resin.
The use of generalizability theory to estimate data reliability in single‐subject observational research
Authors: Lei Pui‐Wa , Smith Maria , Suen Hoi K.
Published: April 2007

Direct observation of behaviors is a data collection method customarily used in clinical and educational settings. Repeated measures and small samples are inherent characteristics of observational studies that pose challenges to the numerical estimation of reliability for observational data. In this article, we review some debates about the use of Generalizability Theory in estimating reliability of single‐subject observational data. We propose that it could be used but under a clearly stated set of conditions. The conceptualization of facets and object of measurement for a common design of observational research is elucidated under a different light. We provide two numerical examples to illustrate the ideas. Limitations of using Generalizability Theory to estimate reliability of observational data are discussed. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 433–439, 2007.
Errors of inference in structural equation modeling
Authors: McCoach D. Betsy , Black Anne C. , O'Connell Ann A.
Published: April 2007

Although structural equation modeling (SEM) is one of the most comprehensive and flexible approaches to data analysis currently available, it is nonetheless prone to researcher misuse and misconceptions. This article offers a brief overview of the unique capabilities of SEM and discusses common sources of user error in drawing conclusions from these analyses. We make recommendations to guide proper analytical practices and appropriate inferences and provide references for more advanced study. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 461–470, 2007.
Statistical reform: Evidence‐based practice, meta‐analyses, and single subject designs
Authors: Jenson William R. , Clark Elaine , Kircher John C. , Kristjansson Sean D.
Published: April 2007

Evidence‐based practice approaches to interventions has come of age and promises to provide a new standard of excellence for school psychologists. This article describes several definitions of evidence‐based practice and the problems associated with traditional statistical analyses that rely on rejection of the null hypothesis for the establishment of invention effectiveness. Meta‐analysis as an approach to ascertain EBPs is reviewed along with the inherent difficulties associated with single subject design research such as autocorrelations. Four meta‐analytic approaches are reviewed which include Percentage of Nonoverlapping Data points (PND), the Busk and Serlin: Assumption models, ITSACORR, and Hierarchical Linear Modeling (HLM). HLM is offered as the most promising approach for the analysis for single subject designs. Monte Carlo simulations are modeled with varying degrees of autocorrelations, differing numbers of data points, and simulated effects sizes to show that HLM is an acceptable approach for controlling the risk of Type I errors. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 483–493, 2007.
Synthesis, characterization and photoinduction of optical anisotropy in liquid crystalline diblock azo‐copolymers
Authors: Forcén P. , Oriol L. , Sánchez C. , Alcalá R. , Hvilsted S. , Jankova K. , Loos J.
Published: April 2007

Diblock copolymers with polymethyl methacrylate and side chain liquid crystalline (LC) azopolymethacrylate blocks were synthesized by atom transfer radical polymerization (ATRP). The azobenzene content in these copolymers ranges from 52 to 7 wt %. For an azo content down to 20% they exhibit a LC behavior similar to that of the azo homopolymers. Thin films of these copolymers were characterized by transmission electron microscopy (TEM). A lamellar nanostructure was observed for azo content down to 20 wt %, while no structure is observed for the copolymer with a 7% azo content. The optical anisotropy induced in these films by illumination with linearly polarized 488 nm light was studied and the results compared with those of the azo homopolymer and of a random copolymer with a similar composition. The formation of azo aggregates inside the azo blocks is strongly reduced in going from the homopolymer to the copolymers. Photoinduced azo orientation perpendicular to the 488 nm light polarization was found in all the polymers. The orientational order parameter is very similar in the homopolymer and in the block copolymers with an azo content down to 20 wt %, while it is much lower in the random copolymer and in the 7 wt %. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1899–1910, 2007
Structural and functional characterization of binding sites in metallocarboxypeptidases based on Optimal Docking Area analysis
Authors: Fernández Daniel , Vendrell Josep , Avilés Francesc X. , Fernández‐Recio Juan
Published: April 2007

The metallocarboxypeptidases (MCPs) belonging to the clan MC were studied by the Optimal Docking Area (ODA) method to evaluate protein–protein binding sites and to provide a basis for the identification of binding partners for this class of enzymes. The ODA method identifies surface patches with optimal desolvation energy based on the selection of low‐energy docking regions, generated from a set of surface points around the protein. With few exceptions, the ODA method identified surface patches with a significant low‐energy docking surface for all the MCPs with known three‐dimensional structure. Overall, in 14 out of 24 cases, the detected ODA patches were correctly located (i.e. more than 50% of the predicted residues were in known protein–protein binding sites), yielding a global success rate of 58%. More specifically, the success rate increased up to 80% on the ODA patches detected for the catalytic domains of the M14A subfamily, independently on the partner. Interestingly, the ODA residues on the catalytic domain were correctly located in the interface with the N‐terminal pro domain in all MCPs. The spatial distribution of the ODA patches for the different members of the family is in relation to the origin and function of the particular MCP, which allowed distinguishing between them. In good agreement with the experimentally characterized protein interfaces, the total average surface area of the theoretically derived ODA patches for the catalytic domain of MCPs is around 1700 Å2and their content in hydrophobic residues is about 40%. As a particular case, the average surface area of the ODA patches in MCPs of crop insect pests is about twice that of the MCPs of vertebrates, which might be related to their particular function. We recognized two binding regions for the catalytic domain of the MCPs, one of them accounting for nearly all the known intermolecular interactions made up by the enzymes. Protein inhibitors seem to have evolved to dock on this subset of ODA patches, evoking the binding mode of the N‐terminal pro domains. The second binding region detected, for which no ligands have been identified so far, seems to be related to the acquisition/maintenance of the native structure of the peptidase. Overall, the ODA method has been successful in identifying low‐energy docking areas in a set of structurally and functionally related proteins, suggesting that it can be easily extended to other families in the search for protein–protein binding sites and for their functional significance. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Differentiability of Lieb functional in electronic density functional theory
Authors: Lammert Paul E.
Published: April 2007

A solid understanding of the Lieb functional FL is important because of its centrality in the foundations of electronic density functional theory. A basic question is whether directional derivatives of FL at an ensemble‐V‐representable density are given by (minus) the potential. A widely accepted purported proof that FL is Gâteaux differentiable at EV‐representable densities would say, “yes.” But that proof is fallacious, as shown here. FL is not Gâteaux differentiable in the normal sense, nor is it continuous. By means of a constructive approach, however, we are able to show that the derivative of FL at an EV‐representable density ρ0 in the direction of ρ1 is given by the potential if ρ0 and ρ1 are everywhere strictly greater than zero, and they and the ground state wave function have square integrable derivatives through second order. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
What they know vs. what they do: how acquirers leverage technology acquisitions
Authors: Puranam Phanish , Srikanth Kannan
Published: April 2007

Existing research suggests that in acquisitions of small technology‐based firms by large established firms post‐merger integration both enables and hinders acquirers' efforts to leverage the technology of acquired firms. This apparent paradox can be resolved once we account for the qualitatively distinct ways in which acquirers leverage technology acquisitions. Integration helps acquirers use the acquired firm's existing knowledge as an input to their own innovation processes (leveraging what they know), but hinders their reliance on the acquired firm as an independent source of ongoing innovation (leveraging what they do). We also show that experienced acquirers are better able to mitigate the disruptive consequences of the loss of autonomy entailed by integration, though we find no evidence that they achieve greater coordination benefits from integration. Copyright © 2007 John Wiley & Sons, Ltd.
Going global: Turning strategic vision into operational reality
Authors: Goehle Donna G.
Published: April 2007

How does a U.S. firm make the quantum leap from a domestic company to a global business? A study of 20 of the most successful U.S. MNCs suggests it's not just a matter of setting new strategic directions or operational plans.
The maquiladora option in Mexico
Authors: Minogue Raymond P.
Published: April 2007

If a U.S. firm can manage around the problems of labor turnover and poor infrastructure, Mexico's maquiladora sector will offer considerable cost savings, with reasonable operational risks, well into the 1990s.
The total acquisition cost of buying internationally
Authors: Dollar W. E.
Published: April 2007

There's a big difference between “landed cost” and the real cost that a buyer of foreign goods pays. These other costs need to be understood if the right purchase decision in the global marketplace is to be made.
A four‐step approach to 1992
Authors: Williams Robert , Teagan Mark , Beneyto Jose
Published: April 2007

Here's a four‐step process to help you analyze both the opportunities and potential hazards of 1992. Even if you've already made your plans, it's a way to make sure you've considered all the implications of a Single Europe.
Real estate issues in corporate relocation in Western Europe
Authors: Burt Andrew
Published: April 2007

If you plan to relocate an office or plant in Europe to take advantage of Europe 1992, you need some understanding of European real estate markets and their effects on corporate relocation decisions.
Eastern Europe: Narrowing the management gap through training
Authors: Terry Robert C.
Published: April 2007

Local managers in Eastern Europe are eager and energetic, but they lack knowledge and experience in business. MNCs that plan to enter into ventures with organizations there must include in their plans management training and development efforts if they want their new partners to run successful organizations.
What the uruguay round means to service firms
Authors: Riddle Dorothy
Published: April 2007

What are the implications of the GATT talks on liberalizing trade in services? Here we examine six typical concerns of service firms as they go abroad and what the impact will be, if any, of the talks in Geneva on each situation.
Processes that contribute to resilience among youth in foster care
Authors: Drapeau Sylvie , Saint‐Jacques Marie‐Christine , Lépine Rachel , Bégin Gilles , Bernard Martine
Published: April 2007

The objective of this qualitative research is to better understand the processes that contribute to resilience among adolescents in foster care. Twelve boys and girls (X=15.9 years), identified as resilient, participated in this study. The mean duration of the teenagers’ placement is 7.3 years. The results point to three types of turning points: action, relation and reflection. Four processes, directly or indirectly linked to the turning point, have also been identified: increase in perceived self‐efficacy, distancing oneself from the risks, new opportunities, and the multiplication of benefits.
Diagnostic criteria and follow‐up parameters in complex regional pain syndrome type I – a Delphi survey
Authors: Brunner Florian , Lienhardt Stephanie B. , Kissling Rudolf O. , Bachmann Lucas M. , Weber Ulrich
Published: April 2007

Background: Although the current clinical guideline of diagnostic criteria for the complex regional pain syndrome I (CRPS I) is a landmark endeavour to define this complex condition it does not prioritise its most important clinical manifestations.

Aim: We set out to obtain an expert agreed priority list of diagnostic and follow‐up parameters in the diagnosis and management of CRPS I.

Methods: A two round Delphi survey: We asked international experts to list (first round) and weight (second round) parameters (scale 1–10) they believed to be relevant in diagnosis and follow‐up. Median ratings and interquartile ranges (IQR) were calculated. Rates ≥7 and IQR ≤3 depicted important and expert agreed parameters.

Results: Thirty‐two diagnostic and 23 follow‐up listings and ratings of 13 experts were available for analysis. In three domains (clinical presentation, further examinations and follow‐up) experts agreed on the following parameters, pain (10; 9–10) with its subcategories hyperesthesia (7; 5–8) hyperalgesia (8; 8–8) and allodynia (8; 7–10), signs with oedema (9; 8–10) and colour change (8; 5–8) and mobility with its categories motor change (7; 5–8) and decreased range of motion (8; 8–8). The experts agreed that no further examinations were necessary for diagnosis (10; 8–10). The agreed important follow‐up parameter was clinical course (10; 8–10) with its categories decrease in pain (8; 8–9) and hyperalgesia (8; 6–8), decreased oedema (8; 7–10) and improvements in motor function (10; 8–10) and strength (8; 6–9).

Conclusion: This expert survey conveys an agreed set of relevant diagnostic parameters of CRPS I and proposes that in follow‐up examinations treatment success should be based on restoration of those manifestations.
Predictive factors of chronic pain and disability in whiplash: A Delphi poll
Authors: Miró Jordi , Nieto Rubén , Huguet Anna
Published: April 2007

The purpose of this study was to establish consensus on what factors might predict chronic pain and disability in whiplash injuries following motor vehicle collisions.

A Delphi poll involving two rounds of data collection was used as a way to reach consensus among participating experts.

Participating experts identified several physical, historical, psychological, and behavioral response factors that they believed were related to the development of chronic pain and related disability in people who have developed whiplash‐associated disorders. These included: (1) prior history: previous history of chronic pain; (2) physical factors: high severity of injury, presence of constant neck pain since the accident; (3) psychological factors: belief that pain mean danger and that he or she should avoid exercise, tendency to somatize, to have positive thoughts about pain, catastrophic thinking, low self‐efficacy expectancies, and to have symptoms of posttraumatic stress disorders; and (4) behavioral responses to symptoms: avoidance of activities that involve moving the neck through fear of experiencing more pain, and restriction in the use and movement of the neck.

These findings may be used to help identify the specific domains that should be assessed in studies seeking to predict which individuals are at risk to develop chronic pain and disability following initial whiplash‐associated disorders sustained in crash. If these results are supported by future studies, then they could be used to help develop intervention programs that could prevent long‐term pain and disability in whiplash patients who are considered to be at risk to develop chronic disabling pain problems.
Brushing cytology in cutaneous lesions of the head and neck
Authors: Tamiolakis D , Proimos E , Perogamvrakis G E , Skoulakis C E , Georgiou G C , Papadakis C E
Published: April 2007

Background: Brushing cytology is a well established diagnostic procedure used by gynaecologists, physicians and surgeons to obtain representative samples from lesions. Our aim was to evaluate its reliability in ulcerative and tumour-like conditions arising in the skin of the head and neck.

Methods: Over 28 months, 86 patients with suspected cutaneous malignant lesions underwent a cytological examination with a cytobrush within the otolaryngology department.

Results: Cytological analysis identified 63 out of 64 histologically documented malignant tumours (60 primary basal cell and squamous cell carcinomas and three metastatic adenocarcinomas), and 21 out of 22 benign lesions. There was one false positive and one false negative result.

Conclusions: Brushing cytology of suspected cutaneous malignant lesions is a rapid and reliable diagnostic method which helps the clinician to decide on appropriate planning and treatment. The technique can be performed as an out-patient procedure, and smear preparation can be done in the laboratory, even at a peripheral hospital.
On the relation between extremes of midlatitude cyclones and the atmospheric circulation using ERA40
Authors: Raible C. C.
Published: April 2007

Analyzing ERA40 data there is evidence that extreme intensified midlatitude cyclones are related to the large‐scale atmospheric circulation in winter and to a minor degree for spring and autumn. Regionally different circulation patterns are related to extreme intensified cyclones, e.g., cyclones in northern Europe are linked to a slightly rotated NAO‐like pattern whereas for southern Europe a blocking‐like pattern over central to northern Europe is observed. In the Pacific a north‐south dipole pattern is related to extremes in cyclone intensity. In summer these relationships, however, collapse. In winter, depending on the considered region, changes in the meridional temperature gradient, the land‐sea temperature contrast, and to some extent changes in static stability modulate the lower to middle tropospheric baroclinicity, being important in the intensification process.
Wiener optimal combination and evaluation of the Gravity Recovery and Climate Experiment (GRACE) gravity fields over Antarctica
Authors: Sasgen I. , Martinec Z. , Fleming K.
Published: April 2007

We present an appraisal method for the Gravity Recovery and Climate Experiment (GRACE) gravity field releases based on the Wiener optimal evaluation approach. The Wiener optimal evaluation uses linear convolution filtering and the subsequent addition of multiple inputs to minimize (in a least squares sense) the difference between the combined optimal output and a desired output. Investigating the individual filtered outputs with respect to the desired output provides a measure of the quality of each input. Here, the inputs are linear trends of the gravity field change over Antarctica inferred from the Stokes potential coefficients of the four independent GRACE releases: GFZ RL03, CSR RL01C, JPL RL01C, and CNES RL01C, each with at least 27 months worth of data. The desired output is based on the predicted gravity field change over Antarctica resulting from present‐day ice mass changes and ongoing glacial isostatic adjustment. We demonstrate that the combined output of the Wiener optimal evaluator improves the quality of the signal over Antarctica with regards to the desired output. We show that three of the four GRACE releases essentially constitute the desired signal in the optimal combination, while one mainly reduces the contaminating noise over the oceans. The best agreement with the predicted gravity field change over Antarctica is represented by the release CNES RL01C.
Quantifying Arctic ozone loss during the 2004–2005 winter using satellite observations and a chemical transport model
Authors: Singleton C. S. , Randall C. E. , Harvey V. L. , Chipperfield M. P. , Feng W. , Manney G. L. , Froidevaux L. , Boone C. D. , Bernath P. F. , Walker K. A. , McElroy C. T. , Hoppel K. W.
Published: April 2007

During the last decade, much attention has been placed on quantifying and modeling Arctic stratospheric O3 loss. At issue in particular is the reliability of models for simulating the loss under variable dynamical conditions in the Arctic region. This paper describes inferred O3 loss calculations for the 2004–2005 Arctic winter using data from four solar occultation satellite instruments, as well as the Earth Observing System Microwave Limb Sounder (EOS MLS). O3 loss is quantified with the “Chemical Transport Model (CTM) passive subtraction” approach, using a passive O3 tracer field from the SLIMCAT CTM. The 2004–2005 Arctic winter was moderately active dynamically, but was still one of the coldest Arctic winters on record, with prime conditions for O3 loss. Loss estimates inferred from all of the different satellite instruments peaked in mid‐March at 450 K between 2–2.3 ppmv, slightly less than similar estimations for the cold 1999–2000 winter. The SLIMCAT CTM was also used to simulate O3 for the 2004–2005 winter. In March, near 450 K, the model O3 was 0.3 ppmv (∼10–15%) lower than the observations, leading to a maximum O3 loss that was 10–15% larger than that inferred from observations, using the passive subtraction approach. Modeled loss maximized around the same time as that inferred from observations. Although some discrepancies between the observed and modeled O3 remain, the level of agreement presented here shows that the SLIMCAT CTM was able to satisfactorily simulate O3 and polar O3 loss during the dynamically active 2004–2005 Arctic winter.
Anti‐BDCA‐4 (neuropilin‐1) antibody can suppress virus‐induced IFN‐alpha production of plasmacytoid dendritic cells
Authors: Grage‐Griebenow Evelin , Löseke Stefan , Kauth Marion , Gehlhar Kirsten , Zawatzky Rainer , Bufe Albrecht
Published: April 2007

Plasmacytoid dendritic cells (PDC) in human blood are the main source of virus‐induced interferon (IFN)‐alpha. They exhibit a lineage‐negative phenotype but all express BDCA‐4, which is homologous to the neuronal receptor neuropilin‐1. Specific staining with anti‐BDCA‐4 antibody is used for positive isolation of PDC from blood by magnetic cells sorting. Here, it is demonstrated that these positively selected PDC showed reduced or completely abolished IFN‐alpha release compared to unstained PDC, which were negatively selected by magnetic depletion of lineage‐positive blood mononuclear cells. In addition, treatment of these unstained PDC with anti‐BDCA‐4 mAb also resulted in at least two‐fold lower or reduced virus‐induced IFN‐alpha production. It is shown that the antibody not only affects cell survival or block virus attachment but also reduces IFN‐alpha release induced by non‐viral CpG oligodeoxynucleotides. In conclusion, data suggest an immunoregulatory role for BDCA‐4 on PDC as demonstrated for IFN‐alpha response to virus.