bluuebunny/crossref_metadata_2025 huggingface dataset:
Combustion and Thermal Behavior of Polyurethane Acrylate Modified with a Phosphorus Monomer
Authors: Xilei Chen  , Yuan Hu  , Lei Song  , Weiyi Xing
Published: February 2008

A series of UV curable flame retardant resins were obtained by blending bis(2-acryloxyethyl) 2.6.7-trioxa-1-phosphabicyclo[2.2.2.]octane-4-methylol-1-oxide phosphate (MDMPE) in certain ratios with a commercial polyurethane acrylate (PUA). It has been found that the cured film shows good flame retardancy when the MDMPE is at 30% additive level. The cone calorimeter results show that the heat release rate decreases in comparison with the pure PUA. The thermogravimetric analysis (TGA) and real time Fourier-transform infrared spectroscopy measurements (RTFTIR) results show that the phosphate group in MDMPE first degrades to form poly(phosphoric acid) before the degradation of PUA. Then, the formed poly(phosphoric acid) effectively promotes the conversion of PUA to form char, which prevents the sample from further burning. It can be concluded that MDMPE could catalyze the degradation of PUA to form char residue, and could be used as a UV curable flame retardant which acts by a condensed phase mechanism.
Transient Ceiling Jet Temperature and Velocity Profiles in the Presence of an Upper Layer: Comparison with Predictions by LAVENT and JET Computer Fire Models
Authors: Motevalli Vahid , Riahi Siamak
Published: February 2008

Results of a scaled experimental study are compared with the predictions produced by the LAVENT and JET computer fire models. As in most large-scale fire testing, characterization of heat release rate (HRR) and accuracy of its measurement creates a lot of uncertainty for validation of these codes. Sensitivity of LAVENT results to the assumed radiative loss of 35% is examined by varying the total HRR which corresponds to varying the convective HRR. Comparisons show that LAVENT uses the wall-jet theory at its core for prediction of the ceiling jet flow and thus does not capture the ceiling jet profile well and overpredicts the upper layer temperature during the development of the layer. The velocity is generally overpredicted since the retardation of the jet momentum by the upper layer does not seem to be modeled accurately. JET has a better user interface and slightly different parameters, but does not provide ceiling jet profiles. The major difference between JET and LAVENT include the ceiling jet temperature and velocity algorithms, the fusible link algorithms, and the use of a variable radiative fraction as a function of fire size and type.
Further Application of the Semenov Model to Evaluate the Possibility of Spontaneous Combustion in Tumble Dryers
Authors: Morrison D.R. , Ogle R.A.
Published: February 2008

Previously, Jones applied the Semenov boundary conditions and thermal explosion theory to the problem of predicting spontaneous combustion of laundered clothing in a commercial tumble dryer. This problem is revisited here with a modification of the limiting assumptions made in the previous work. Relaxation of the limiting assumptions (i.e., considering air flow through the drum) demonstrates that the self-heating processes within the laundered load are limited by the forced convection through the tumbling clothing load. The conclusions of this paper demonstrate that inclusion of this heat loss term soundly refutes the possibility of spontaneous combustion of an uncontaminated, tumbling clothing load. The critical temperature predictions indicate that even in the case of overheating of the garment load (dryer malfunction), the garment load temperature is unlikely to exceed its critical temperature in the absence of contamination.
Properties and Structure of Polypropylene/ Polyethylene-Octene Elastomer/Nano CaCO 3 Composites
Authors: Hanim H. , Fuad M.Y. Ahmad , Zarina R. , Ishak Z.A. Mohd , Hassan Azman
Published: February 2008

Polypropylene (PP)-based nanocomposites were developed by the incorporation of a novel nano-sized precipitated calcium carbonate (NPCC) nanoparticles and polyethylene—octene elastomer (POE). The NPCC filler loading selected were 10 and 15wt.% while the POE contents were varied between 0 and 30wt.%. A slight decrease in the tensile strength of the PP nanocomposites was observed with increasing NPCC content. Results of impact strength indicated that the NPCC filler imparted some toughening effects on the PP and PP/POE blends. Maximum impact strength enhancement was achieved for the PP when blended with 30wt.% POE and filled with 15wt.% NPCC. However, the essential property balance between toughness and stiffness was still lacking in the nanocomposites developed. Differential Scanning Calorimeter results showed that NPCC acted as a nucleating agent for PP, increasing the crystallization temperature of PP by approximately 9°C.
Effect of Nanoclay Content on Void Morphology in Resin Transfer Molded Composites
Authors: Hamidi Youssef K. , Aktas Levent , Altan M. Cengiz
Published: February 2008

Effects of nanoclay content on morphology and spatial distribution of voids in resin transfer molded nanoclay/E-glass/epoxy composite disks are investigated. Closite®25A nanoclay loads of 2, 5, and 10wt% are mixed by sonication with a low-viscosity epoxy resin prior to filling the mold cavity containing 13.6% E-glass preform by volume. A disk without nanoclay is also molded. Once the molded composites are cured, voids on radial composite samples are evaluated via microscopic image analysis. The addition of nanoclay is found to result in a significant increase in the apparent viscosity of the clay-epoxy mixture, thus increasing the molding pressure. Void occurrence is observed to increase considerably with increasing nanoclay content, from 2.1% in the composite without nanoclay to 5.1 and 8.3% in the composites molded with 5 and 10wt% nanoclay, respectively. However, the composite with 2wt% nanoclay yields the lowest void content of 0.7%. Voids are observed to be, in average, smaller after the addition of nanoclay at all nanoclay concentrations. Presence of nanoclay in the impregnating resin induces at least 60% reduction in voids located inside fiber tows, which are trapped by the fluid front motion during impregnation. Irregularly shaped voids are also observed to decrease with increasing nanoclay content. A nonuniform void content and morphology is observed radially, which seems to be affected by the flow kinematics as well as possible breakdown and filtration of clay clusters.
Effects of Antioxidant and Initiator on the Mechanical Properties of Polypropylene—Aspen Composites
Authors: Ruijun Gu  , Kokta Bohuslav V.
Published: February 2008

Studies on the effect of blending method, the introduction method of initiator (dicumyl peroxide, DCP), and the blending time with antioxidant (Irganox) added on the mechanical properties of PP—Aspen composites with and without DCP, respectively are undertaken. An optimum blending time for the composite with Irganox is obtained. The optimum content of Irganox as well as pre-mixing and the final-step feeding-method of DCP are compared to that of conventional method of blending in order to achieve the optimum values of impact and tensile strength properties.
Consultative Elections of Chinese Township Leaders
Authors: Thøgersen Stig , Elklit Jørgen , Lisheng Dong
Published: February 2008

The article presents observations from a 2006 township election experiment in Ya'an Municipality, Sichuan Province. Gradual institutionalization of elections to Chinese village committees has for two decades fascinated those interested in social and political development in rural China. Elections at the next level—the townships—were seen by many, in China and outside, as a natural next step. For this reason, the election of a township mayor in Buyun in 1998 attracted considerable attention, but the official reaction was negative. The elections in Ya'an juxtaposed against this background are of considerable interest as they can be seen as a way of testing the direction and limits of future reforms. The Ya'an elections were not only for the mayor, but also for the entire township leadership, including the township Party secretary. However, the final selection was—as previously—made at higher politico-administrative levels with the voting results serving as just one input to the decision-making process. For this reason, these elections should be termed “consultative,” and we suggest that such consultative elections can become an important tool in the party-state's cadre management.
The Entry of Mainland Chinese Investment into Taiwan
Authors: Cheng Joseph Y.S. , Shixiang Mo
Published: February 2008

This article examines the issues related to the admission of mainland Chinese capital and enterprises into Taiwan triggered off by Taiwan's membership in the World Trade Organization, including the coordination of political views, the adjustments in policies, the revisions of statutes, and the setting up of administrative monitoring mechanisms in Taiwan. The issue of entry represents the interaction of economic and security interests on both sides of the Taiwan Strait, and it reflects the Chinese leadership's united front offensive, the competition among the political parties in Taiwan, and the business community's articulation of its interests in the island. The analysis aims to illustrate legislative and other processes involved in the economic exchanges across the Taiwan Strait. These processes allow various parties concerned to set up obstacles that obstruct the desired economic exchanges. At the same time, the mutual economic interests, or at least the substantial economic interests on one side of the Taiwan Strait, constantly provide the momentum to overcome the obstacles. More importantly, the sophisticated business community can always find ways to overcome the obstacles in pursuit of their interests, for example, use of subsidiaries in tax havens.
The Mental Treatment Act 1945 in Ireland: an historical enquiry
Authors: Kelly Brendan D.
Published: February 2008

The Mental Treatment Act 1945 had a decisive influence on the provision and development of psychiatric services in Ireland. This paper examines: (a) the historical and psychiatric backgrounds to the introduction of the Mental Treatment Act 1945; (b) the main provisions of the Act; and (c) the international context of the Act, especially in relation to institutional and legislative trends in other jurisdictions.
Practical issues arising in an exploratory analysis evaluating progression-free survival as a surrogate endpoint for overall survival in advanced colorectal cancer
Authors: Hughes Michael D
Published: February 2008

This paper is based on a conference presentation in which several authors presented results from analyses of the same dataset concerning the evaluation of progression-free survival (PFS) as a surrogate endpoint for overall survival in advanced colorectal cancer clinical trials. In evaluating a potential surrogate endpoint, there is a hierarchy of information that might usually be considered desirable: 1) a biological rationale for surrogacy, 2) demonstration of the prognostic value of the surrogate endpoint in untreated patients and 3) in treated patients and 4) demonstration across randomized comparisons that differences in the effect of randomized treatments on the surrogate endpoint are associated with the corresponding differences in the effect on the clinical endpoint of interest. Results from analyses that might be used to address the third and four requirements are presented and some of the practical issues that arise in evaluating a surrogate endpoint, which would be relevant to many diseases, are illustrated. Although the results presented should not be seen as a definitive analysis of the value of PFS as a surrogate endpoint, concerns are identified about the potential lack of standardization of the definition of PFS or the frequency of evaluation of disease progression and the high leverage of one study in evaluating the association in addressing the fourth requirement.
Individual- and trial-level surrogacy in colorectal cancer
Authors: Buyse Marc , Burzykowski Tomasz , Michiels Stefan , Carroll Kevin
Published: February 2008

Two conditions must be fulfilled for an intermediate endpoint to be an acceptable surrogate for a true clinical endpoint: (1) there must be a strong association between the surrogate and the true endpoint, and (2) there must be a strong association between the effects of treatment on the surrogate and the true endpoint. We test whether these conditions are fulfilled for disease-free survival (DFS) and progression-free survival (PFS) on data from 20 clinical trials comparing experimental treatments with standard treatments for early and advanced colorectal cancer. The effects of treatment on DFS (or PFS in advanced disease) and OS were quantified through log hazard ratios (log HR), estimated through a Weibull model stratified for trial. The rank correlation coefficients between DFS and OS, and trial-specific treatment effects, were estimated using a bivariate copula distribution for these endpoints. A linear regression model between the estimated log hazard ratios was used to compute the “surrogate threshold effect”, which is the minimum treatment effect on DFS required to predict a non-zero treatment effect on OS in a future trial. In early disease, the rank correlation coefficient between DFS and OS was equal to 0.96 (CI 0.95—0.97). The correlation coefficient between the log hazard ratios was equal to 0.94 (CI 0.87—1.01). The risk reductions were approximately 3% smaller on OS than on DFS, and the surrogate threshold effect corresponded to a DFS hazard ratio of 0.93. In advanced disease, the rank correlation coefficient between PFS and OS was equal to 0.82 (CI 0.82—0.83). The correlation coefficient between the log hazard ratios was equal to 0.99 (CI 0.94—1.04). The risk reductions were approximately 19% smaller on OS than on PFS, and the surrogate threshold effect corresponded to a PFS hazard ratio of 0.86. One trial with a large treatment effect on PFS and OS had a strong influence on the results in advanced disease. DFS (and PFS in advanced disease) are acceptable surrogates for OS in colorectal cancer.
Experimental Investigation of Thermo-Mechanical Behaviors in Ni—Ti Shape Memory Alloy
Authors: Sung Ho Yoon  , Dong Jin Yeo
Published: February 2008

The effect of annealing heat treated temperature, loading rate, environmental temperature, repeated loading cycle on the phase transformation and thermo-mechanical behaviors of shape memory alloy is investigated through a DSC test and a thermo-mechanical test. Shape memory alloy wire with the diameter of 1.1 mm is used and its composition is Ti-56.0wt%Ni. Annealing heat treated temperatures are 300, 400, 500, 600, and 700°C. Loading rates are 0.5, 1.0, 2.0, and 5.0 mm min-1. Environmental temperatures are 17, 25, 32, 33, and 36°C. According to the results, phase transformation temperatures and the peak shapes of DSC curves are influenced by annealing heat treated temperatures. The thermo-mechanical behaviors of shape memory alloy are affected on annealing heat treated temperature, loading rate and environmental temperature. In addition, shape memory alloy might lose its unique characteristics even after unloading under repeated loading cycles or above higher than certain annealing heat treated temperature.
Delamination Monitoring Analysis of CFRP Structures using Multi-Probe Electrical Method
Authors: Todoroki Akira
Published: February 2008

Since a delamination crack is invisible or difficult to detect visually, the delamination causes low reliability of Carbon-Fiber-Reinforced-Polymer (CFRP) for primary structures. To improve the low reliability, smart systems of delamination identifications in-service are desired. Recently, many researchers have employed an Electrical Resistance Change Method (ERCM) to detect the internal damages of CFRP laminates. The ERCM does not require expensive instruments. Author's group has already experimentally investigated the applicability of the ERCM for strain monitoring, delamination crack monitoring and matrix crack monitoring. In the present article, therefore, these results performed in the previous papers are briefly explained. These successful results enable us to monitor a lot of information of the CFRP laminates by means of the electrical resistance changes in many applications, although a lot of electrodes are required to be mounted. To reduce the number of electrodes, a new electrical potential method for the CFRP plate is proposed here, which enables us to reduce the number of electrodes. The present article compared the new method to the method proposed by Anderson. FEM analyses are performed to confirm the applicability of the new method.
Numerical Analysis on Two Kinds of Cymbal Membranes for Piezoelectric Micro-Flow Actuator
Authors: Bangfeng Wang  , Qin Xia
Published: February 2008

The behaviors of two kinds of cymbal piezoelectric-metal composite membrane for piezoelectric synthetic jet actuator (PSJA) are investigated to improve the driving capability of PSJA. The FEM models of piezoelectric-metal composite membranes are established and solved using ANSYS software. Two dimensionless geometry characteristic parameters of membrane, δ1 and δ 2, are defined and used to analyze the influences of geometry on the driving capability of membrane. Cymbal and plane membrane specimens are manufactured and tested to verify the results of simulation. The results of research show that there is an optimal combination between δ1 and δ 2 that improve effectively the deformation and driving capability of PSJA membrane, especially the half cymbal membranes can provide the maximum deformation and driving capability under the same input and boundary condition. δ 1 = 0.5, δ2 = 1.2 is a good combination for half cymbal membrane in the proposed research.
Recent Progress on Distributed Structural Health Monitoring Research at NUAA
Authors: Shenfang Yuan  , Dakai Liang  , Lihua Shi  , Xia Zhao  , Jian Wu  , Gang Li  , Lei Qiu
Published: February 2008

This study introduces recent research advances on the structural health monitoring (SHM) at Nanjing University of Aeronautics and Astronautics (NUAA). Distributed SHM technology for large-scale engineering structures is discussed. First, a hybrid wing box health monitoring evaluation system is presented. This evaluation system is developed to verify the piezoelectric sensor array-based active Lamb wave diagnostic method and the fiber Bragg grating sensor-based structural strain monitoring method. Second, distributed health monitoring technology based on the multi-agent system (MAS) technology is discussed. This research includes the individual agent design, the MAS-based SHM system architecture design, and three important aspects in designing the MAS-based SHM system. An evaluation case is presented in detail to show the advantages of the MAS-based SHM system. Finally, the study illustrates the motivation of the agents realized by a wireless sensor network. The developed wireless sensor nodes are also described.
Nondimensional Herschel—Bulkley Analysis of Magnetorheological and Electrorheological Dampers
Authors: Wereley Norman M.
Published: February 2008

Quasisteady modeling of linear stroke flow mode magnetorheological (MR) (or electrorheological (ER)) dampers has focused primarily on the utilization of the Bingham-plastic constitutive model to assess performance metrics such as damping capacity. In such Bingham-plastic MR (or ER) flows, the variable yield stress of the fluid, τy, is activated by applying magnetic (or electric) field. The Bingham-plastic model assumes that the material is in either (1) a pre-yield condition where the local shear stress is less than the yield stress, τ<τy, or (2) a post-yield condition, where the local shear stress is greater than the yield stress, τ > τ y, so that the material flows with a constant post-yield viscosity. The objective of this study is to analyze the damping capacity of such a controllable MR or ER damper in the situation when the field dependent fluid exhibits post-yield shear thinning or thickening behavior, that is, the post-yield viscosity is a function of shear rate. A Herschel—Bulkley model with a field dependent yield stress is proposed, and the impact of shear rate dependent viscosity on damping capacity is assessed. Key analysis results — velocity profile, pre-yield thickness, and damping coefficient — are presented in a nondimensional formulation that is consistent with prior results for the Bingham-plastic analysis. The nondimensional analysis formulated here clearly establishes the Bingham number as the independent variable for assessing flow mode damper performance.
Free Vibration of Delaminated Unidirectional Sandwich Panels with a Transversely Flexible Core and General Boundary Conditions — A High-Order Approach
Authors: Schwarts-Givli H. , Rabinovitch O. , Frostig Y.
Published: February 2008

A high-order theoretical approach for the free-vibration analysis of delaminated unidirectional sandwich panels with a compressible core is presented. The analytical approach accounts for the flexibility of the core in the vertical direction and the resulting high-order displacement, acceleration, and velocity fields within the core. The existence of delaminated regions along the sandwich panel and the various interfacial stress transfer conditions at the delaminated core-face interface are considered and studied. The analytical model developed in the article is applicable to any type of boundary conditions including different support conditions at the same section. The derivation of the model uses Hamilton's variational principle as well as the beam and lamination theories for the face-sheets and two-dimensional elasticity theory for the modeling of the core. The free-vibration problem is formulated and solved assuming a harmonic behavior in time and using the multiple shooting method along with the Newton—Raphson scheme for the solution in space. Numerical results that emphasize the influence of the boundary conditions, the effect of the delaminated regions, the influence of the contact conditions within the debonded region, and the high-order effects through the depth of the core are presented and discussed. The model and the solution procedure are verified through a comparison with finite elements analyses and with an analytical solution that is based on the Modified Galerkin method. The article closes with a summary and conclusions.
Modeling of Sandwich Structures and Localization of Three-dimensional Stress and Displacement Fields
Authors: Guessasma M. , Saidi A. , Coorevits P.
Published: February 2008

This article deals with the linear behavior of sandwich structures by using homogenization method for periodic media. An orthotropic layered plate model substituting the three-dimensional (3D) structure is proposed. The use of the equivalent model for an industrial example allows the authors to validate the proposed model and shows also its utility for lightweight constructions. In addition, the authors present in this study a method of localization of 3D stress and displacement fields using calculations resulting from the orthotropic layered plate model. An extension to the curved sandwich structures is also carried out by considering a layered shell as an equivalent model.
Femmes Fatales in Finance, or Women and the City
Authors: Czarniawska Barbara
Published: February 2008

This paper concerns the representations of women working with finances in popular culture. Popular culture retrieves plots from a common repertoire, and in this way transmits ideals and furnishes descriptions of reality, but it also teaches practices and provides a means through which practices might be understood. Apart from portraying its own era, it also perpetuates strong plots, i.e. established and repeated patterns of emplotment. One such strong plot seems to be persistent in popular culture's representations of women working with finances. Their fate is depicted along the lines known best from Euripides' tragedies: they transgress `women's place' and commit heroic or mad deeds. By doing so, they might save the city (Athens in the case of Euripides, the City in finance stories), but afterwards they must either die or be sent back. The later part of this paper is dedicated to the case of the banker Robin Saunders that has been reported in two different ways in the UK and Germany, one supporting the strong plot and one defying it, which offers material for reflection on the complexity of both the influence of popular culture and the fate of women in finance.
Fear and Loathing in Harrogate, or a Study of a Conference
Authors: Ford Jackie , Harding Nancy
Published: February 2008

There have been no studies in organization research of conferences as part of the world of work. This paper describes a reflexive ethnographic study of one management conference. It finds that upon arrival at the places and spaces of the conference processes of self-making as conference attendee are set in train. Self-making subsequently takes place within processes of domination and subordination, achieved through fear, infantilization, disparagement and seduction. Reading this through the lens of Freudian-informed interpretations of the Hegelian master/slave dialectic, the paper argues that conferences are one of the means of control over academic, managerial and professional employees. Control is achieved through dialectical interactions between conference and employee.
Speaking Out: The Responsibilities of Management Intellectuals: A Survey
Authors: Dunne Stephen , Harney Stefano , Parker Martin
Published: February 2008

This article discusses our analysis of over 2,000 articles published within 20 top business and management journals. The article empirically demonstrates how little attention is being paid by the work published within these journals to contemporary political issues across the globe. We also demonstrate the extent to which the same is true of `critical' journals such as Organization . To this end we argue that mass scholarly ranking mechanisms, such as the British Research Assessment Exercise (RAE), create a general state of myopia on the part of business and management scholars towards a variety of political issues, even making a virtue out of ignorance in this regard. We suggest that this is not simply a problem for critical management studies and proceed to raise the question of what the responsibility of business and management academia actually is.
Calculation, qualculation, calqulation: shopping cart arithmetic, equipped cognition and the clustered consumer
Authors: Cochoy Franck
Published: February 2008

This paper investigates how such a trivial device as a shopping cart may surprisingly contribute to shaping exchanges in supermarkets. First, the shopping cart completely modifies consumers' calculations. It does so by leading them to accomplish particular gestures, by transforming a budgetary constraint into a volumetric one, and by providing them with true calculative tools. Second, shopping with a cart also implies some `planned' cognitive processes. These processes concern interplay between family needs, selection equipment (such as a shopping list) and market information (packaging, for example). The combination of these elements moves the consumer from mere calculation (price-based computing) to `qualculation' (i.e. quality-based rational judgements). Third, and in particular, since it favours the transformation of the individual consumer into a collective one (or `cluster', i.e. a small group of people gathering around the same device), a shopping cart functions as a scene or as a frame for collective `calqulation' (from the French verb `calquer', i.e. adjusting one's standpoint to that of another, and vice versa).
Making and exchanging a second-hand oil field, considered in an industrial marketing setting
Authors: Finch John H. , Acha Virginia L.
Published: February 2008

Marketing researchers have begun exploring actor network theory as a way of understanding how marketers and marketing concepts contribute to the shaping and developing of markets. This paper strikes out in a new direction by considering the development of a market in an industrial setting, namely for mature or second-hand oil and gas fields, especially in the UK, since the mid-1990s. The market is thin and has no standard mode of exchange. Buyers and sellers develop valuations only in part because oil and gas fields are objects in markets, also representing them as situated in networks of production. Hence, different versions and valuations persist throughout an episode of exchange. The paper suggests that in industrial settings, concerns of production are taken into account in order to support something like a market exchange, rather than spilling over and becoming potential sources of later surprise and upset to otherwise well-ordered exchanges.
The configuration of actors in market practice
Authors: Andersson Per , Aspenberg Katarina , Kjellberg Hans
Published: February 2008

This paper addresses three conceptual challenges concerning actors and agency that arise when taking interest in market practice: i) how agency is awarded in practical situations, ii) how actors are preconfigured, and iii) how actors are represented. These issues are explored in three empirical scenes taken from a case study of the introduction of an e-procurement system at an international transport and logistics company. First, we suggest that practical interaction can be fruitfully regarded as a process of interdefinition involving prescriptions and subscriptions between acting entities, or actants . Second, we employ the term inscription to address efforts to affect in advance the configuration of such actants. Third, we suggest that actors are entities to which actions are ascribed, ex post . Through this secondary process a number of actants may be subsumed under a common actor label, thus offering a way of accounting for agency as part of a practice perspective. We conclude by discussing implications of the proposed vocabulary for multiplicity, reflexivity and market agency.
Marketing mobile futures: assembling constituencies and creating compelling stories for an emerging technology
Authors: Simakova Elena , Neyland Daniel
Published: February 2008

This paper engages with the marketing of an emerging technology: Radio Frequency IDentification (RFID). It is based on a lengthy ethnographic field study with a marketing team in a hi-tech corporation. We argue that building market relations for this emerging technology involves three closely intertwined activities: the identification of relevant people and things which can form a constituency into which the product can be launched; the narration of a tellable story which articulates and renders accountable relations of people and things; and the development of a compelling version of this story to provide a basis for ongoing engagement of the putative constituency. Identifying potential members for the constituency, convincing them of the compelling nature of the mobility based story, managing access to the constituency and maintaining internal relations between the marketing team and the rest of the corporate organization are all ongoing aspects of this market building activity. The paper forms a contribution to marketing theory by bringing ideas of constituencies, tellable and compelling stories from science and technology studies research together with insights from the literature on marketing.
Pitch-catch Active Sensing Methods in Structural Health Monitoring for Aircraft Structures
Authors: Ihn Jeong-Beom , Chang Fu-Kuo
Published: February 2008

This study presents active sensing methods in structural health monitoring, for detecting cracks and debonds in metallic and composite structures, which can be potentially implemented into airframe structures. First, a pitch-catch method using a pair of piezoelectric actuator and sensor is introduced to generate a damage indeX which can be used to characterize damage at a known location. Tests on airbus fuselage panels are conducted to verify the method and damage indeX. The damage indeX relates changes in the energy content of a specific Lamb wave mode selected by group velocity analysis to the eXtent of damage. Second, an imaging method based on multiple pitch-catch information, a network of piezoelectric actuator/sensors, is presented for characterizing damage (location and size) without need for a structural or damage model. The imaging method with an autofocusing feature is applied to aluminum plates and a stiffened composite panel for method verification.
Action research in teacher education
Authors: Kitchen Julian , Stevens Dianne
Published: February 2008

Two teacher-educators, an instructor and a teaching assistant, designed an action research project focused on enhancing their professional practice and the practice of their students by introducing the preservice teachers to action research. Both teacher-educators viewed this decision as progressive and emancipatory, as action research encourages inquiry and reflection, connects theory to practice, and creates links between preservice and in-service teaching. Simultaneously, the teacher-educators integrated preservice curriculae, modeling the enriched teaching and learning that can result from an interdisciplinary approach. Data include preservice teachers' action research proposals, reports and reflections, as well as the teacher-educators' reflections and collaborative conversations. Instructors used self-study methodology to reflect on their effectiveness in enhancing the professional lives of their students and themselves. A significant number of preservice teachers indicated that engaging in action research expanded their conceptions of teaching; such expansion holds potential for fostering change in schools.
Review: Innate immunity to tropical theileriosis
Authors: Ahmed Jabbar S. , Glass Elizabeth J. , Salih Diaeldin A. , Seitzer Ulrike
Published: February 2008

The intracellular protozoan parasite Theileria annulata causes a severe, and often fatal, disease of pure and cross-bred cattle in tropical and subtropical countries. The present review refers to the importance of innate immunity as far as it is known to date in this infectious disease. Specifically, macrophages and the mediators produced by these cells are outlined. In addition, the latest findings concerning cattle breed differences in susceptibility to T. annulata infection in relation to macrophage activation are discussed.
Clearance of bacterial lipopolysaccharides and lipid A by the liver and the role of arginino-succinate synthase
Authors: Satoh Motonobu , Ando Shingo , Shinoda Takehiro , Yamazaki Masatoshi
Published: February 2008

The liver is thought to be involved in the systemic clearance and detoxification of lipopolysaccharide (LPS). Argininosuccinate synthase (AS), a liver cytosolic urea cycle enzyme, has been found to bind to and inactivate LPS and lipid A. To elucidate the participation of AS in the clearance of LPS by liver and hepatocytes, we investigated the correlation between AS content and the removal of lipid A and LPS in vivo and in vitro, tracing levels of biological activity. A hepatotoxic model in which mice were injected with CCl4 revealed a significant reduction in lipid A clearance along with liver failure on day 1; total body clearance was changed to 0.534 ml/min from 1.42 ml/min. AS content in liver concomitantly decreased to about half and AS leaked to blood at about 6 µg/ml. Total body clearance of i.v. injected AS was estimated at 0.083 ml/min, which predicted about 24-h leakage of AS after CCl4 injection. The treatment also reduced the clearance of R-type LPSs to a lesser degree the larger its polysaccharide portion. S-type LPS, which has a large O-antigen polysaccharide, exhibited enhancement of clearance on CCl4 treatment. When pretreated in vitro with AS and injected into normal mice, lipid A and R-type LPS showed a similar pattern of clearance of residual activities to the untreated forms, but S-type LPS exhibited enhancement of clearance. Comparison between different strains of mice revealed a correlation of AS content in liver and lipid A clearance, where the higher AS strain C3H/He mice showed a more rapid clearance than the lower AS strains C57BL/6 and BALB/c. Primary spheroid cultures of hepatocytes treated with 0.1 µM dexamethasone and 1 µM glucagon showed about a 2-fold increase in AS amount and a more rapid clearance of LPS from culture medium than untreated cells. These results suggest that AS in hepatocytes may be involved in the process of lipid A and LPS clearance and the extracellular leakage of AS may also participate in the systemic detoxification.
Folimycin (concanamycin A) inhibits LPS-induced nitric oxide production and reduces surface localization of TLR4 in murine macrophages
Authors: Eswarappa Sandeepa M. , Basu Nirmalya , Joy Omana , Chakravortty Dipshikha
Published: February 2008

Lipopolysaccharide (LPS) is a major cell wall component of Gram-negative bacteria and signals through a receptor complex which consists of TLR4, MD-2 and CD14. LPS signaling in macrophages induces the production of many pro-inflammatory molecules, including nitric oxide (NO). In this study, we have shown that folimycin, a macrolide antibiotic and a specific inhibitor of vacuolar ATPase (V-ATPase), inhibits LPS-induced NO production, but not TNFα production, in murine elicited peritoneal macrophages. However, folimycin did not affect interferon-γ induced NO production. LPS-induced iNOS mRNA and protein expression and NF-κB activation were also inhibited by folimycin. Interestingly, folimycin-treated cells showed reduced surface expression of TLR4 molecules and dilated Golgi apparatus. These findings suggest that folimycin, by inhibiting V-ATPases, alters intra-Golgi pH, which in turn causes defective processing and reduced surface expression of TLR4 reducing the strength of LPS signaling in murine macrophages.
Structure of a novel lipid A obtained from the lipopolysaccharide of Caulobacter crescentus
Authors: Smit John , Kaltashov Igor A. , Cotter Robert J. , Vinogradov Evgeny , Perry Malcolm B. , Haider Hibba , Qureshi Nilofer
Published: February 2008

Caulobacter crescentus CB15 is a dimorphic bacterium that is best known as a prokaryotic model for cell development. However, it is also being exploited in biotechnology, where the crystalline surface (S-layer) protein secretion system has been adapted for heterologous protein display or secretion. Because the S-layer attaches to the cell surface via lipopolysaccharide (LPS) and since the LPS represents a potential endotoxin contaminant of recombinant proteins, the lipid A component was examined in detail. LPS was acid hydrolyzed to obtain crude lipid A, which was methylated and purified by HPLC. HPLC peak fractions were analyzed by mass spectrometry and nuclear magnetic resonance spectroscopy. The structure of the major lipid A of C. crescentus comprised the tetrasaccharide backbone α-D-GalpA-(1→4)-β-D-DAG-(1→6)-α-D-DAG-(1→1)-α-D-GalpA substituted with six fatty acids, and a molecular mass of 1875 (GalpA, galactopyranuronic acid; DAG, 2,3-diamino-2,3-dideoxyglucopyranose). No phosphate residues were detected. The major lipid A component had 12:0[3-O[Δ5-12:1(3-OH)]] and 12:0[3-O(Δ5-12:1)] fatty acyl chains at either the 3′- or the 2′ positions of the distal subunit DAG B, and 12:0(3OH) and 12:0[3,6-(OH) 2] fatty acyl chains at 3- and 2- positions of the reducing end subunit DAG A, respectively. In addition, several other variations in the structure were observed. The LPS was evaluated for TNF-α inducing activity and consistent with its unusual lipid A structure (relative to that of enteric bacteria), the activity was reduced by greater than 100-fold as compared to Escherichia coli ReLPS. This and other evidence suggests the potential application of this lipid A as a vaccine adjuvant or the suitability of Caulobacter displaying antigens for formulation of whole cell vaccines.
A functional TNFRSF5 gene variant is associated with risk of lymphoma
Authors: Skibola Christine F. , Nieters Alexandra , Bracci Paige M. , Curry John D. , Agana Luz , Skibola Danica R. , Hubbard Alan , Becker Nikolaus , Smith Martyn T. , Holly Elizabeth A.
Published: February 2008

CD40 and its ligand, CD154, are major costimulatory molecules whose interactions are important in humoral and cellular immunity. We hypothesized that single nucleotide polymorphisms (SNPs) in TNFRSF5 and TNFSF5 encoding the CD40 and CD154 proteins, respectively, influence lymphoma risk, particularly a functional TNFRSF5 SNP (−1C>T, rs1883832) associated with reduced B-cell CD40 expression. TNFRSF5 and TNFSF5 SNPs were examined in a population-based case-control study of non-Hodgkin lymphoma (376 cases/801 controls with DNA), and compelling findings were followed up in 2 independent populations. Pooled analyses of all 3 case-control studies (total N = 1776 non-Hodgkin lymphoma cases, N = 2482 controls) revealed an increased risk of follicular lymphoma (FL) associated with the TNFRSF5 −1TT genotype (odds ratio = 1.6; 95% confidence interval, 1.1-2.4). In addition, among women, an inverse association was found between the variant A allele for a TNFSF5 6809G>A SNP and FL risk (OR = .61; 95% CI, 0.36-0.98). In genotype-phenotype studies, significantly reduced circulating soluble CD40 was observed in TNFRSF5 −1TT compared with −1CC carriers. Further, dendritic cells from those with −1TT versus −1CC genotypes exhibited lower CD40 cell surface expression. These results suggest that the TNFRSF5 −1C>T polymorphism may increase FL susceptibility through mechanisms that hinder cellular immune responses. Further studies are needed to explore these findings.
Prediction of mucin-type O-glycosylation sites in mammalian proteins using the composition of k-spaced amino acid pairs
Authors: Chen Yong-Zi , Tang Yu-Rong , Sheng Zhi-Ya , Zhang Ziding
Published: February 2008

Background

As one of the most common protein post-translational modifications, glycosylation is involved in a variety of important biological processes. Computational identification of glycosylation sites in protein sequences becomes increasingly important in the post-genomic era. A new encoding scheme was employed to improve the prediction of mucin-type O-glycosylation sites in mammalian proteins.

Results

A new protein bioinformatics tool, CKSAAP_OGlySite, was developed to predict mucin-type O-glycosylation serine/threonine (S/T) sites in mammalian proteins. Using the composition of k-spaced amino acid pairs (CKSAAP) based encoding scheme, the proposed method was trained and tested in a new and stringent O-glycosylation dataset with the assistance of Support Vector Machine (SVM). When the ratio of O-glycosylation to non-glycosylation sites in training datasets was set as 1:1, 10-fold cross-validation tests showed that the proposed method yielded a high accuracy of 83.1% and 81.4% in predicting O-glycosylated S and T sites, respectively. Based on the same datasets, CKSAAP_OGlySite resulted in a higher accuracy than the conventional binary encoding based method (about +5.0%). When trained and tested in 1:5 datasets, the CKSAAP encoding showed a more significant improvement than the binary encoding. We also merged the training datasets of S and T sites and integrated the prediction of S and T sites into one single predictor (i.e. S+T predictor). Either in 1:1 or 1:5 datasets, the performance of this S+T predictor was always slightly better than those predictors where S and T sites were independently predicted, suggesting that the molecular recognition of O-glycosylated S/T sites seems to be similar and the increase of the S+T predictor's accuracy may be a result of expanded training datasets. Moreover, CKSAAP_OGlySite was also shown to have better performance when benchmarked against two existing predictors.

Conclusion

Because of CKSAAP encoding's ability of reflecting characteristics of the sequences surrounding mucin-type O-glycosylation sites, CKSAAP_ OGlySite has been proved more powerful than the conventional binary encoding based method. This suggests that it can be used as a competitive mucin-type O-glycosylation site predictor to the biological community. CKSAAP_OGlySite is now available at http://bioinformatics.cau.edu.cn/zzd_lab/CKSAAP_OGlySite/.
Association mapping of partitioning loci in barley
Authors: Cockram James , White Jon , Leigh Fiona J , Lea Vincent J , Chiapparino Elena , Laurie David A , Mackay Ian J , Powell Wayne , O'Sullivan Donal M
Published: February 2008

Background

Association mapping, initially developed in human disease genetics, is now being applied to plant species. The model speciesArabidopsisprovided some of the first examples of association mapping in plants, identifying previously cloned flowering time genes, despite high population sub-structure. More recently, association genetics has been applied to barley, where breeding activity has resulted in a high degree of population sub-structure. A major genotypic division within barley is that between winter- and spring-sown varieties, which differ in their requirement for vernalization to promote subsequent flowering. To date, all attempts to validate association genetics in barley by identifying major flowering time loci that control vernalization requirement (VRN-H1andVRN-H2) have failed. Here, we validate the use of association genetics in barley by identifyingVRN-H1andVRN-H2, despite their prominent role in determining population sub-structure.

Results

By taking barley as a typical inbreeding crop, and seasonal growth habit as a major partitioning phenotype, we develop an association mapping approach which successfully identifiesVRN-H1andVRN-H2, the underlying loci largely responsible for this agronomic division. We find a combination of Structured Association followed by Genomic Control to correct for population structure and inflation of the test statistic, resolved significant associations only withVRN-H1and theVRN-H2candidate genes, as well as two genes closely linked toVRN-H1(HvCSFs1andHvPHYC).

Conclusion

We show that, after employing appropriate statistical methods to correct for population sub-structure, the genome-wide partitioning effect of allelic status atVRN-H1andVRN-H2does not result in the high levels of spurious association expected to occur in highly structured samples. Furthermore, we demonstrate that bothVRN-H1and the candidateVRN-H2genes can be identified using association mapping. Discrimination between intragenicVRN-H1markers was achieved, indicating that candidate causative polymorphisms may be discerned and prioritised within a larger set of positive associations. This proof of concept study demonstrates the feasibility of association mapping in barley, even within highly structured populations. A major advantage of this method is that it does not require large numbers of genome-wide markers, and is therefore suitable for fine mapping and candidate gene evaluation, especially in species for which large numbers of genetic markers are either unavailable or too costly.