17 resultados para major epitope on CII

em Aston University Research Archive


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Adjuvants are often composed of different constituents that can be divided into two groups based on their primary activity: the delivery system which carries and presents the vaccine antigen to antigen-presenting cells, and the immunostimulator that activates and modulates the ensuing immune response. Herein, we have investigated the importance of the delivery system and in particular its physical characteristics by comparing the delivery properties of two lipids which differ only in the degree of saturation of the acyl chains, rendering the liposomes either rigid (DDA, dimethyldioctadecylammonium) or highly fluid (DODA, dimethyldioleoylammonium) at physiological temperature. We show that these delivery systems are remarkably different in their ability to prime a Th1-directed immune response with the rigid DDA-based liposomes inducing a response more than 100 times higher compared to that obtained with the fluid DODA-based liposomes. Upon injection with a vaccine antigen, DDA-based liposomes form a vaccine depot that results in a continuous attraction of antigen-presenting cells that engulf a high amount of adjuvant and are subsequently efficiently activated as measured by an elevated expression of the co-stimulatory molecules CD40 and CD86. In contrast, the fluid DODA-based liposomes are more rapidly removed from the site of injection resulting in a lower up-regulation of co-stimulatory CD40 and CD86 molecules on adjuvant-positive antigen-presenting cells. Additionally, the vaccine antigen is readily dissociated from the DODA-based liposomes leading to a population of antigen-presenting cells that are antigen-positive but adjuvant-negative and consequently are not activated. These studies demonstrate the importance of studying in vivo characteristics of the vaccine components and furthermore show that physicochemical properties of the delivery system have a major impact on the vaccine-induced immune response. © 2012 Elsevier B.V. All rights reserved.

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Investment in transport infrastructure can be highly sensitive to uncertainty. The scale and lead time of strategic transport programmes are such that they require continuing policy support and accurate forecasting. Delay, cost escalation and abandonment of projects often result if these conditions are not present. In Part One the physical characteristics of infrastructure are identified as a major constraint on planning processes. The extent to which strategies and techniques acknowledge these constraints is examined. A simple simulation model is developed to evaluate the effects on system development of variations in the scale and lead time of investments. In Part Two, two case studies of strategic infrastructure investment are analysed. The absence of a policy consensus for airport location was an important factor in the delayed resolution of the Third London Airport issue. In London itself, the traffic and environmental effects of major highway investment ultimately resulted in the abandonment of plans to construct urban motorways. In both cases, the infrastructure implications of alternative strategies are reviewed with reference to the problems of uncertainty. In conclusion, the scale of infrastructure investment is considered the most important of the constraints on the processes of transport planning. Adequate appraisal of such constraints may best be achieved by evaluation more closely aligned to policy objectives.

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The effect of stainless steel, glass, zirconium and titanium enamel surfaces on the thermal and photooxidative toughening mechanism of dehydrated castor oil films deposited on these surfaces was investigated using different analytical and spectroscopic methods. The conjugated and non-conjugated double bonds were identified and quantified using both Raman spectroscopy and 1D and 2D NMR spectroscopy. The disappearance of the double bonds in thermally oxidised oil-on-surface films was shown to be concomitant with the formation of hydroperoxides (determined by iodometric titration). The type of the surface had a major effect on the rate of thermal oxidation of the oil, but all of the surfaces examined had resulted in a significantly higher rate of oxidation compared to that of the neat oil. The highest effect was exhibited by the stainless steel surface followed by zirconium enamel, titanium enamel and glass. The rate of thermal oxidation of the oil-on-steel surface (at 100 °C, based on peroxide values) was more than five times faster than that of oil-on-glass and more than 21 times faster than the neat oil when compared under similar thermal oxidative conditions. The rate of photooxidation at 60 °C of oil-on-steel films was found to be about one and half times faster than their rate of thermal oxidation at the same temperature. Results from absorbance reflectance infrared microscopy with line scans taken across the depth of thermally oxidised oil-on-steel films suggest that the thermal oxidative toughening mechanism of the oil occurs by two different reaction pathways with the film outermost layers, i.e. furthest away from the steel surface, oxidising through a traditional free radical oxidation process involving the formation of various oxygenated products formed from the decomposition of allylic hydroperoxides, whereas, in the deeper layers closer to the steel surface, crosslinking reactions predominate.

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Aim: Salt formation is a widely used approach to improve the physicochemical and solid state properties of an active pharmaceutical ingredient. In order to better understand the relationships between the active drug, the selected counterion and the resultant salt form, crystalline salts were formed using four different carboxylic acid drugs and a closely related series of amine counterions. Thirty-six related crystalline salts were prepared, characterized and the relationship between solubility and dissolution behaviour and other properties of the salt and the counterion studied. Methods: Salts of four model acid drugs, gemfibrozil, flurbiprofen, ibuprofen and etodolac were prepared using the counterions butylamine, hexylamine, octylamine, benzylamine, cyclohexylamine, tert-butylamine, 2-amino-2-methylpropan-1-ol, 2-amino-2-methylpropan-1,3-diol andtris(hydroxymethyl)aminomethane. Salt formation was confirmed, the salts were characterized and their corresponding solubilities determined and rationalized with respect to the counterions' properties. Results and conclusion: The properties of the salt highly dependent on the nature of the counterion and, although there is considerable variation, some general conclusion can be drawn. For the alkyl amines series, increasing chain length leads to a reduction in solubility across all the acidic drugs studied and a reduction in melting point, thus contradicting simplistic relationships between solubility and melting point. Small, compact counterions consistently produce crystalline salts with high melting point accompanied with a modest improvement in solubility and the nature of hydrogen bonding between the ions has a major impact on the solubility. © 2012 Informa Healthcare USA, Inc.

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This study investigates fast pyrolysis bio-oils produced from alkali-metal-impregnated biomass (beech wood). The impregnation aim is to study the catalytic cracking of the pyrolysis vapors as a result of potassium or phosphorus. It is recognized that potassium and phosphorus in biomass can have a major impact on the thermal conversion processes. When biomass is pyrolyzed in the presence of alkali metal cations, catalytic cracking of the pyrolysis liquids occurs in the vapor phase, reducing the organic liquids produced and increasing yields of water, char, and gas, resulting in a bio-oil that has a lower calorific value and an increased chance of phase separation. Beech wood was impregnated with potassium or phosphorus (K impregnation and P impregnation, respectively) in the range of 0.10-2.00 wt %. Analytical pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) was used to examine the pyrolysis products during thermal degradation, and thermogravimetric analysis (TGA) was used to examine the distribution of char and volatiles. Both potassium and phosphorus are seen to catalyze the pyrolytic decomposition of biomass and modify the yields of products. 3-Furaldehyde and levoglucosenone become more dominant products upon P impregnation, pointing to rearrangement and dehydration routes during the pyrolysis process. Potassium has a significant influence on cellulose and hemicellulose decomposition, not just on the formation of levoglucosan but also other species, such as 2(5H)-furanone or hydroxymethyl-cyclopentene derivatives. Fast pyrolysis processing has also been undertaken using a laboratory-scale continuously fed bubbling fluidized-bed reactor with a nominal capacity of 1 kg h-1 at the reaction temperature of 525 °C. An increase in the viscosity of the bio-oil during the stability assessment tests was observed with an increasing percentage of impregnation for both additives. This is because bio-oil undergoes polymerization while placed in storage as a result of the inorganic content. The majority of inorganics are concentrated in the char, but small amounts are entrained in the pyrolysis vapors and, therefore, end up in the bio-oil.

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Automatic Term Recognition (ATR) is a fundamental processing step preceding more complex tasks such as semantic search and ontology learning. From a large number of methodologies available in the literature only a few are able to handle both single and multi-word terms. In this paper we present a comparison of five such algorithms and propose a combined approach using a voting mechanism. We evaluated the six approaches using two different corpora and show how the voting algorithm performs best on one corpus (a collection of texts from Wikipedia) and less well using the Genia corpus (a standard life science corpus). This indicates that choice and design of corpus has a major impact on the evaluation of term recognition algorithms. Our experiments also showed that single-word terms can be equally important and occupy a fairly large proportion in certain domains. As a result, algorithms that ignore single-word terms may cause problems to tasks built on top of ATR. Effective ATR systems also need to take into account both the unstructured text and the structured aspects and this means information extraction techniques need to be integrated into the term recognition process.

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The success of recruitment efforts can have a major impact on sales force effectiveness. Students have long been considered a good source of potential sales recruits, but research has found students have generally negative perceptions of selling as a career. One reason for such perceptions may be negative stereotypes of salespeople held by students. However information on the content of UK sales stereotypes remains anecdotal at best. This study empirically examines UK business students' stereotypes of salespeople using a two-stage approach. Findings suggest that these stereotypes are generally negative. However, we create profiles of salespeople using our findings, and consequently uncover some positive aspects to the stereotype. The study provides instruction on how to use stereotypes in subsequent work, as well as how to utilise the profiles in recruitment efforts.

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In this article, the authors report the findings of an exploratory study that examines the challenges of developing a market orientation in China, the world’s largest transitional economy. The findings suggest that though managerial actions are relevant, in transitional economies, environmental factors—most notably, government policies—are a major influence on firms’ aspirations to be market oriented.

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Common problems encountered in clinical sensing are those of non-biocompatibility, and slow response time of the device. The latter, also applying to chemical sensors, is possibly due to a lack of understanding of polymer support or membrane properties and hence failure to optimise membranes chosen for specific sensor applications. Hydrogels can be described as polymers which swell in water. In addition to this, the presence of water in the polymer matrix offers some control of biocompatibility. They thus provide a medium through which rapid transport of a sensed species to an incorporated reagent could occur. This work considers the feasibility of such a system, leading to the design and construction of an optical sensor test bed. The development of suitable membrane systems and of suitable coating techniques in order to apply them to the fibre optics is described. Initial results obtained from hydrogel coatings implied that the refractive index change in the polymer matrix, due to a change in water content with pH is the major factor contributing to the sensor response. However the presence of the colourimetric reagent was also altering the output signal obtained. An analysis of factors contributing to the overall response, such as colour change and membrane composition were made on both the test bed, via optical response, and on whole membranes via measurement of water content change. The investigation of coatings with low equilibrium water contents, of less than 10% was carried out and in fact a clearer signal response from the test bed was noted. Again these membranes were suprisingly responding via refractive index change, with the reagent playing a primary role in obtaining a sensible or non-random response, although not in a colourimetric fashion. A photographic study of these coatings revealed some clues as to the physical nature of these coatings and hence partially explained this phenomenon. A study of the transport properties of the most successful membrane, on a coated wire electrode and also on the fibre optic test bed, in a series of test environments, indicated that the reagent was possibly acting as an ion exchanger and hence having a major influence on transport and therefore sensor characteristics.

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The recent history of small shop and independent retailing has been one of decline. The most desirable form of assistance is the provision of information which will increase the efficiency model of marketing mix effeciveness which may be applied in small scale retailing. A further aim is to enhance theoretical development in the marketing field. Recent changes in retailing have affected location, product range, pricing and promotion practices. Although a large number of variables representing aspects of the marketing mix may be identified, it is not possible, on the basis of currently available information, to quantify or rank them according to their effect on sales performance. In designing a suitable study a major issue is that of access to a suitable representative sample of small retailers. The publish nature of the retail activities involved facilitates the use of a novel observation approach to data collection. A cross-sectional survey research design was used focussing on a clustered random sample of greengrocers and gent's fashion outfitters in the West Midlands. Linear multiple regression was the main analytical technique. Powerful regression models were evolved for both types of retailing. For greengrocers the major influences on trade are pedestrian traffic and shelf display space. For gent's outfitters they are centrality-to-other shopping, advertising and shelf display space. The models may be utilised by retailers to determine the relative strength of marketing mix variables. The level of precision is not sufficient to permit cost benefit analysis. Comparison of the findings for the two distinct kinds of business studied suggests an overall model of marketing mix effectiveness might be based on frequency of purchase, homogeneity of the shopping environment, elasticity of demand and bulk characteristics of the good sold by a shop.

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Task classification is introduced as a method for the evaluation of monitoring behaviour in different task situations. On the basis of an analysis of different monitoring tasks, a task classification system comprising four task 'dimensions' is proposed. The perceptual speed and flexibility of closure categories, which are identified with signal discrimination type, comprise the principal dimension in this taxonomy, the others being sense modality, the time course of events, and source complexity. It is also proposed that decision theory provides the most complete method for the analysis of performance in monitoring tasks. Several different aspects of decision theory in relation to monitoring behaviour are described. A method is also outlined whereby both accuracy and latency measures of performance may be analysed within the same decision theory framework. Eight experiments and an organizational study are reported. The results show that a distinction can be made between the perceptual efficiency (sensitivity) of a monitor and his criterial level of response, and that in most monitoring situations, there is no decrement in efficiency over the work period, but an increase in the strictness of the response criterion. The range of tasks exhibiting either or both of these performance trends can be specified within the task classification system. In particular, it is shown that a sensitivity decrement is only obtained for 'speed' tasks with a high stimulation rate. A distinctive feature of 'speed' tasks is that target detection requires the discrimination of a change in a stimulus relative to preceding stimuli, whereas in 'closure' tasks, the information required for the discrimination of targets is presented at the same point In time. In the final study, the specification of tasks yielding sensitivity decrements is shown to be consistent with a task classification analysis of the monitoring literature. It is also demonstrated that the signal type dimension has a major influence on the consistency of individual differences in performance in different tasks. The results provide an empirical validation for the 'speed' and 'closure' categories, and suggest that individual differences are not completely task specific but are dependent on the demands common to different tasks. Task classification is therefore shovn to enable improved generalizations to be made of the factors affecting 1) performance trends over time, and 2) the consistencv of performance in different tasks. A decision theory analysis of response latencies is shown to support the view that criterion shifts are obtained in some tasks, while sensitivity shifts are obtained in others. The results of a psychophysiological study also suggest that evoked potential latency measures may provide temporal correlates of criterion shifts in monitoring tasks. Among other results, the finding that the latencies of negative responses do not increase over time is taken to invalidate arousal-based theories of performance trends over a work period. An interpretation in terms of expectancy, however, provides a more reliable explanation of criterion shifts. Although the mechanisms underlying the sensitivity decrement are not completely clear, the results rule out 'unitary' theories such as observing response and coupling theory. It is suggested that an interpretation in terms of the memory data limitations on information processing provides the most parsimonious explanation of all the results in the literature relating to sensitivity decrement. Task classification therefore enables the refinement and selection of theories of monitoring behaviour in terms of their reliability in generalizing predictions to a wide range of tasks. It is thus concluded that task classification and decision theory provide a reliable basis for the assessment and analysis of monitoring behaviour in different task situations.

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This article is linked to my major study on the Poetik des Extremen by classifying the monstrous works of Marianne Fritz among a genealogy of extremist writing in German-speaking literature. Her literary project Festung, which represents in all likelihood the most extensive ‘novel’ in Western literary history, is first analysed by looking at the exponential growth of its components from a paperback of 108 pages to the not yet completed novel Naturgemäß, which will most probably comprise 15 volumes, mostly of A4 size and a length that should be equivalent to over 20,000 standard pages. In parallel to the quantitative explosion of form, the article also explores the transgression of traditional narration and Fritz’s typographical innovations of text presentation. Using reproductions of the late facsimile volumes, an exemplary ‘close reading’ of one page from Naturgemäß II is undertaken to demonstrate the enormous density of Festung. Finally, the article seeks to differentiate Fritz’s opus magnum from other out-sized works of literature by focussing on the specific interconnection between the quantitative and stylistic explosion of the form of the novel, which makes it incomparable to the major works of writers such as Robert Musil or Arno Schmidt.

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Purpose - The main aim of the research is to shed light on the role of information and communication technology (ICT) in the logistics innovation process of small and medium-sized third party logistics providers (3PLs). Design/methodology/approach - A triangulated research strategy was designed using a combination of quantitative and qualitative methods. The former involved the use of a questionnaire survey of small and medium-sized Italian 3PLs with 153 usable responses received. The latter comprised a series of focus groups and the use of seven case studies. Findings - There is a relatively low level of ICT expenditure with few companies adopting formal technology investment strategies. The findings highlight the strategic importance of supply chain integration for 3PLs with companies that have embarked on an expansion of their service portfolios showing a higher level of both ICT usage and information integration. Lack of technology skills in the workforce is a major constraint on ICT adoption. Given the proliferation of logistics-related ICT tools and applications in recent years it has been difficult for small and medium-sized 3PLs to select appropriate applications. Research limitations/implications - The paper provides practical guidelines to researchers in the effective use of mixed-methods research based on the concept of methodological triangulation. In particular, it shows how questionnaire surveys, focus groups and case study analysis can be used in combination to provide insights into multi-faceted supply chain phenomena. It also identifies several potentially fruitful avenues for future research in this specific field. Practical implications - The paper's findings provide useful guidance for practitioners on the effective adoption of ICT as part of the logistics innovation process. The findings also provide support for ICT vendors in the design of ICT solutions that are aligned to the needs of small 3PLs. Originality/value - There is currently a paucity of research into the drivers and inhibitors of ICT in the innovation processes of small and medium-sized 3PLs. This paper fills this gap by exploring the issue using a range of complementary research approaches. Copyright © 2013 Emerald Group Publishing Limited. All rights reserved.

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Particle breakage due to fluid flow through various geometries can have a major influence on the performance of particle/fluid processes and on the product quality characteristics of particle/fluid products. In this study, whey protein precipitate dispersions were used as a case study to investigate the effect of flow intensity and exposure time on the breakage of these precipitate particles. Computational fluid dynamic (CFD) simulations were performed to evaluate the turbulent eddy dissipation rate (TED) and associated exposure time along various flow geometries. The focus of this work is on the predictive modelling of particle breakage in particle/fluid systems. A number of breakage models were developed to relate TED and exposure time to particle breakage. The suitability of these breakage models was evaluated for their ability to predict the experimentally determined breakage of the whey protein precipitate particles. A "power-law threshold" breakage model was found to provide a satisfactory capability for predicting the breakage of the whey protein precipitate particles. The whey protein precipitate dispersions were propelled through a number of different geometries such as bends, tees and elbows, and the model accurately predicted the mean particle size attained after flow through these geometries. © 2005 Elsevier Ltd. All rights reserved.

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Full text: The title of the book gives us a major clue on the innovative approach developed by Anne Freadman in her analysis of a particular Colette corpus, the one devoted to auto-biographical writing: Les Vrilles de la vigne, Mes apprentissages, La Maison de Claudine, Sido ,L’E ́toile Vesper and Le Fanal bleu. Freadman follows the powerful lure of Rimbaldianvieilles vieilleries and its echoes with Colette’s fondness for collecting objects, people and memories. To this must be added a technical aspect, that of the study of the genre of Colette’s writing. Freadman argues that, by largely avoiding the autobiographical form, the writer achieves a new way of ‘telling time’, collecting anecdotes and detail taken from the quotidian and setting them within an all-encompassing preoccupation with time. This provides the second part of the title.The sonata form directs the sequence of the book, orchestrated into five parts,from ‘exposition’ to ‘first subject’ to‘bridge’ to ‘second subject’ to ‘recapitulation’. This has the advantage of enabling Freadman to move and progress between distinct themes—autobiography first,then alternative forms—with grace,whilst preserving within her own writing what she sees as the essence of Colette’s relationship to time in her ‘Livres-Souvenirs’, the telling of time. This‘telling of time’ is itself therefore cleverly subjected to the time constraints and freedoms of musical composition. Freadman’s ‘Exposition’ takes us through a discussion of the autobiographical genre, analysing the texts against anumber of theorists, from Lejeune to Benjamin and Ricoeur, before launching into ‘Colette and Autobiography’. It argues pertinently that Colette did not write a ‘sustained’ autobiography, even inthe most autobiographical of her writings, Mes apprentissages. Measured against Goodwin’s three sources for autobiography, confession, apologia and memoirs, Colette’s autobiographical writings appear to be at odds with all of them. Freadman then goes on in Part II of her argument, to persuasively uncover a project that rejects self-scrutiny and with no autobiographical strategy. In ‘Collecting Time’, despite claims of continuity, narrative logic and causality areabandoned in favour of a collection offragments, family stories that are built up generation after generation into familylegends. A close and fruitful analysis of Sidoleads us to a study of ‘The Art of Ending’, concentrating on L’E ́toile Vesperandle Fanal Bleu. The closing chapter gives a fascinating reading of La Naissance du jouras an exemplar of the way in which the two subjects developed in Freadman’s volume are cast together:Colette’s own working through the autobiographical genre, and her refusal to write memoirs, in favour of collecting memories, and the strategies she uses for her purpose. In ‘Recapitulation’, her concluding chapter, Freadman adroitlyen capsulates her analysis in a fetching title: ‘Fables of Time’. Indeed, the wholepremise of her book is to move away from autobiographical genre, having acknowledged the links and debt the corpus owes to it, and into a study of the multiple and fruitful ways in which Colette tells time.The rich and varied readings of thematerial, competently informed by theoretical input, together with acute sensitivity to the corpus, mark out this study as incontournable for Colette scholars.