bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of the Arabidopsis Transcriptome by Oxidative Stress
Authors: Desikan Radhika , A.-H.-Mackerness Soheila , Hancock John T. , Neill Steven J.
Published: July 2002

Oxidative stress, resulting from an imbalance in the accumulation and removal of reactive oxygen species such as hydrogen peroxide (H2O2), is a challenge faced by all aerobic organisms. In plants, exposure to various abiotic and biotic stresses results in accumulation of H2O2 and oxidative stress. Increasing evidence indicates that H2O2functions as a stress signal in plants, mediating adaptive responses to various stresses. To analyze cellular responses to H2O2, we have undertaken a large-scale analysis of the Arabidopsis transcriptome during oxidative stress. Using cDNA microarray technology, we identified 175 non-redundant expressed sequence tags that are regulated by H2O2. Of these, 113 are induced and 62 are repressed by H2O2. A substantial proportion of these expressed sequence tags have predicted functions in cell rescue and defense processes. RNA-blot analyses of selected genes were used to verify the microarray data and extend them to demonstrate that other stresses such as wilting, UV irradiation, and elicitor challenge also induce the expression of many of these genes, both independently of, and, in some cases, via H2O2.
Maize Genes Encoding the Small Subunit of ADP- Glucose Pyrophosphorylase
Authors: Hannah L. Curtis , Shaw Janine R. , Giroux Michael J. , Reyss Agnes , Prioul Jean-Louis , Bae Jung-Myung , Lee Jung-Youn
Published: July 2002

Plant ADP-glucose pyrophosphorylase (AGP) is a heterotetrameric enzyme composed of two large and two small subunits. Here, we report the structures of the maize (Zea mays) genes encoding AGP small subunits of leaf and endosperm. Excluding exon 1, protein-encoding sequences of the two genes are nearly identical. Exon 1 coding sequences, however, possess no similarity. Introns are placed in identical positions and exhibit obvious sequence similarity. Size differences are primarily due to insertions and duplications, hallmarks of transposable element visitation. Comparison of the maize genes with other plant AGP small subunit genes leads to a number of noteworthy inferences concerning the evolution of these genes. The small subunit gene can be divided into two modules. One module, encompassing all coding information except that derived from exon 1, displays striking similarity among all genes. It is surprising that members from eudicots form one group, whereas those from cereals form a second group. This implies that the duplications giving rise to family members occurred at least twice and after the separation of eudicots and monocot cereals. One intron within this module may have had a transposon origin. A different evolutionary history is suggested for exon 1. These sequences define three distinct groups, two of which come from cereal seeds. This distinction likely has functional significance because cereal endosperm AGPs are cytosolic, whereas all other forms appear to be plastid localized. Finally, whereas barley (Hordeum vulgare) reportedly employs only one gene to encode the small subunit of the seed and leaf, maize utilizes the two genes described here.
Effect of environmental factors on the atmospheric corrosion of mild steel in aggressive sea coastal environment
Authors: Ahmad Zaki , Allam I.M. , Abdul Aleem B.J.
Published: July 2002

The eastern coast of Saudi Arabia has one of the most corrosive environments in the world. Dhahran is therefore an ideal location for the study of atmospheric corrosion. One out of every seven cars in the region is corroded. The atmosphere is contaminated by SO2and a high concentration of suspended particulate matter (SPM) containing sand, salt and carbon particles, exceeding the World Health Organization (WHO) and Middle East Environmental Protection Agency (MEPA) limits most of the time. Corrosion proceeds in the Dhahran atmosphere at a R.H. as low as 40 per cent. At locations close to the sea (1.5 Km), β‐FeOOH is the major corrosion product and α‐ and γ‐FeOOH with some aluminates, silicates and hydrocarbons the minor products. At a location remote from the sea α‐ and γ‐FeOOH are found to be the major corrosion products as shown by XRD and FTIR spectroscopy. The concentration of hydrogen ions, chloride ions and SO2appears to control the corrosion process during the initial exposure period up to one year and the adsorption of anions on the corrosion product films in the later period.
Regional imagery and quality products: the Irish experience
Authors: Henchion Maeve , McIntyre Bridín
Published: July 2002

Regional imagery is increasingly being recognised as having a commercial value for the products of under‐developed areas. It provides a subjective source of quality differentiation. Results of a consumer survey in Ireland indicate that region of origin is an important consideration for two out of three consumers when deciding to buy quality products and that products from rural areas are generally perceived to be of high quality. However, the links between region and quality products are under‐developed as indicated by the fact that Ireland is seen as a single region and the low level of awareness for selected regional labels. The development of territorial linkages must be based on geographical sub‐divisions of relevance to consumers and must be carefully managed to avoid unnecessary competition and duplication of effort. Discusses the use of regional imagery, reviews the meaning of quality, and presents the results of a survey of Irish consumers focusing on their perceptions and behaviour in relation to regional quality products. It also draws some conclusions and makes recommendations of relevance to policy makers and local development agencies in particular.
Telling tales at work: narrative insight into managers’ actions
Authors: Hannabuss Stuart
Published: July 2002

Narrative is discussed as a way of making sense of the world of work. Qualitative research in organisations often falls short of discovering the ethnographic or agent‐centred meanings and assumptions which underlie action. It is argued that eliciting and analysing managerial narratives helps researchers identify the implicit reasoning and assumptive knowledge that underlies decisions and actions. It also allows respondents to provide narrative representations of how they see the past, present and future in their work and attain a fuller degree of coherent understanding. Research like this can shed valuable light on both the tacit and explicit knowledge in the organisation.
“Graduateness” – who cares? Graduate identity in small hospitality firms
Authors: Jameson Stephanie M. , Holden Rick
Published: July 2002

Discusses the second phase of a project on graduate employment in small hospitality firms. It explores the data from the first phase of the project using the concept of graduate identity. The views of both graduates and their managers are examined. The reflections on the data suggest that a complex relationship exists between graduates, their managers and graduate identity. Suggests that hospitality graduates in small firms fail to develop a sense of graduate identity and that their managers lack understanding on how the employment of graduates “makes some difference”. Nevertheless, it is affirmed that graduate identity offers a useful perspective for much‐needed further research on the transition of graduates into SME employment.
Developing cross‐cultural capability in undergraduate business education: implications for the student experience
Authors: Laughton David , Ottewill Roger
Published: July 2002

Draws on relevant academic literature to explore the nature of cross‐cultural capability and goes on to consider its implications for the student experience in British undergraduate business education. Some of the key issues concerning the design of mechanisms and strategies for integrating cross‐cultural capability within the curriculum are highlighted and discussed with a view to informing what needs to be done to prepare undergraduates for the international business world of tomorrow
Maximizing the hospitality management student work placement
experience: a case study
Authors: McMahon Una , Quinn Ursula
Published: July 2002

Placement is an important component of third level hospitality
management programmes and is one of the most vital experiences on which
graduates base their career aspirations. The effect of changing
demographics on the workforce is likely to have an impact on the way
hospitality employers recruit and retain managers. At present, however,
significant numbers of graduates are turning their backs on the
industry. The onus is on educators and industry to ensure that the
placement experience is as rewarding as possible. Presents a developing
model of good practice based on the tripartite relationship between the
University of Ulster, the student and Ryan Hotels. Demonstrates the need
for colleges to build up successful relationships with individual
companies and calls on colleges to invest the necessary resources in the
placement function. Companies must develop a professional attitude
towards placement and students should be positive and forthright in
their attitude to the whole process.
Improving selection interviews with structure: organisations’ use of “behavioural” interviews
Authors: Barclay Jean M.
Published: July 2002

Explains the advantages of behavioural interviewing as a method of employee selection. Reports on a survey of UK organisations’ use of behavioural interviewing in selection. Both interviewers and candidates were positive about the technique. Benefits identified were better quality information gathering leading to improved selection decisions, more consistency and improved skills of interviewers, as well providing candidates with better opportunities to explain their skills. Concerns were raised regarding the training, practice and time required, scoring procedures and possible limitations in respect of certain candidates. Links with wider use of competencies in HRM are examined as well as links with other selection methods. Concludes that behavioural interviewing has significant benefits in improving selection and can also be applied to other interviewing situations such as discipline and grievance. Discusses implications for interviewers, candidates and trainers. Issues for further research are outlined.
Implementing local pay: rhetorically analysing irritation
Authors: Hamilton Peter
Published: July 2002

Examines the introduction of local pay bargaining in a National Health Service Trust. The focus of the article is the irritation experienced by a senior manager responsible for its implementation and operation. Rhetorically deconstructs the manager’s exasperation, highlighting in the process the contingent organizational world he operates within, as well as the manager’s monologic solution to the justified concerns of health professionals about the potentially damaging effects of local pay.
Getting to Know Your Non‐Users
Authors: McCarthy Grace
Published: July 2002

For an in‐house library, getting to know one′s non‐users can be as
important as getting to know one′s user. Non‐users are not necessarily
anti‐library. Non‐users may receive information from their immediate
subordinates, rather than retrieve and evaluate it themselves. Factory
workers may find little to help them in the academic literature. Some
advanced researchers may keep up to date with developments in their
field through conferences, committees and journals they take directly.
There are non‐users who have their own access to databases either by
direct subscription or through professional institutions or research
associations. There are non‐users who might be able to use the
librarian′s skills in non‐traditional library roles. By finding out why
people are not using the library, we can find out if there are ways in
which we can provide a service to them, and we may find ways of
improving the service we offer to all our users.
Knowledge‐related skills and effective career management
Authors: Anakwe Uzoamaka P. , Hall James C. , Schor Susan M.
Published: July 2002

This study addresses recent changes in the career development climate in the USA in which individuals have ultimate responsibility for managing their own careers. We examined empirically the relationship between a relevant set of skills relating to self‐knowledge, interpersonal knowledge, environmental knowledge and effective career management. Data were gathered from 446 students and graduates who had completed a 28‐week, two‐semester managerial skills course within the past five years. The correlation and regression results provide strong support for the hypothesized relationships. The findings reveal that reported acquisition and utilization of skills relating to self‐knowledge, interpersonal knowledge, and environmental knowledge are associated with personal learning, goal setting, career strategies, and career decision making. Implications and directions for future studies are discussed.
Change leadership: the virtues of deviance
Authors: Crom Steve , Bertels Thomas
Published: July 2002

As the limiting factor in many change efforts is having enough talent to replicate and sustain changes once they have been successfully piloted, there is a need for developing the internal talent to lead change. The change leadership concept assumes that successful ideas already exist in the organisation, but that replicating these ideas alone will not be sufficient. Instead of forcing the organisation to accept one given solution, the program identifies ideas which can be replicated within each particular organisational unit, utilising the principles of positive deviance for managing change. Unlike benchmarking, positive deviance does not focus on solutions but on identifying underlying successful behaviours inside the organisation. This approach helps to develop leadership talent, accelerate organisational learning, encourage results‐oriented change that can be sustained, provide a vehicle for results replication, encourage cross‐cultural/cross‐business/cross‐functional learning and enable leaders to initiate change in a variety of business situations.
Marking of products with fluorescent tracers in binary combinations for automatic identification and sorting
Authors: Rafi Ahmad S.
Published: July 2002

The technology for optical identification and automatic sorting of products marked with fluorescent materials in trace concentrations is described. A small number of such materials in binary combinations allows marking of a large number of products. The concept has been applied to sort custom‐made domestic plastic products of different types in a fast‐moving mixed stream. The performance of the optical sensor, developed on the basis of identifying fluorescence signatures of some selected markers in these products, has been tested in an industrial singulation and sorting system. Commercially viable sorting rate and purity of “sort” have been demonstrated. The concept is applicable to other industry sectors.
Knowledge value chain
Authors: Chyi Lee Ching , Yang Jie
Published: July 2002

Introduces the knowledge value chain model as a knowledge management (KM) framework. The model consists of knowledge infrastructure (knowledge worker recruitment, knowledge storage capacity, customer/supplier relationship and CKO and management), the process of KM (knowledge acquisition, knowledge innovation, knowledge protection, knowledge integration, and knowledge dissemination), and the interaction among those components resulting in knowledge performance. Further to the discussion of knowledge value chain (KVC), the following viewpoint was proposed: KM guides the way a corporation performs individual knowledge activities and organizes its entire KVC. It was suggested that competitive advantage grows out of the way corporations organize and perform discrete activities in knowledge value chain which should be measured by the core competence of corporation. This article also provides a cross‐reference for e‐commerce researchers and practitioners.
Annual CREMRU‐JCI survey of corporate real estate practices in Europe and North America: 1993‐1999
Authors: Bon Ranko , Luck Rachael
Published: July 2002

The annual survey of corporate real estate practices has been conducted by CREMRU since 1993, and in collaboration with JCI since 1997. The survey has been supported by IDRC and NACORE, two leading professional associations concerned with corporate real estate. In 1999 IDRC endorsed the survey and opened it to a wider audience. This summary of the seven annual surveys focuses on the incidence of corporate real estate management (CREM) policies, functions and activities, as well as the assessment of knowledge or skills relevant to the CREM function in the future. Both are of vital interest to educational institutions concerned with this field, as well as the personnel and training functions within organizations concerned with better management of their property.
Assessment of facilities management performance in higher education properties
Authors: Amaratunga Dilanthi , Baldry David
Published: July 2002

In the general facilities management literature, it is assumed that there is a causal link between facilities management practices and performance. The role of facilities management in facilitating organisational performance, and thereby in providing competitive advantage, is widely acknowledged. However, the mechanisms of how this happens in higher educational establishments are quite unclear, prompting performance evaluation researchers to question whether performance evaluation in fact does add value, and enhance organisational performance. Assessment of performance of buildings of institutions delivering higher educational services has become a matter of particular interest to governments seeking to increase the effectiveness of educational provision and maximise value for money. This paper presents initial findings of the characteristics of important aspects of a performance evaluation approach related to higher education properties, and discusses the development of a framework based on the balanced scorecard to measure performance relating to higher education establishments.
Integrated portfolio strategies for dynamic organizations
Authors: Becker Franklin
Published: July 2002

Technology, mergers and acquisitions, changing workforce demographics, constantly shifting organizational strategies, new ways of working, global competition – all of these factors generate chronic organizational uncertainty. This article focuses on the nature of integrated portfolio strategies (IPS) which companies in North America and Europe have adopted to manage organizational uncertainty. It draws on the developing work on the science of complexity and adaptive strategies to explore issues of standardization and customization, supply chain relationships, knowledge and workplace options. It argues that uncertainty is best met with a diverse set of options that continually emerge and disappear over time in response to changing business conditions.
Opinion paper: Interlending in the hybrid library – how long will we provide the service?
Authors: Mark Niels
Published: July 2002

In all academic libraries the developments within new information technology, information handling, new categories of materials and publications, and new user demands have changed the traditional use of the library. But in most libraries there has been no decrease in traditional use, so libraries have to cope with the situation of being a hybrid library where traditional services combine with virtual library functions. The article deals with the problems libraries face in this situation and the opportunities presented under these new conditions. A special focus in the article has been placed on competition. What are the threats and the opportunities for libraries in a future in which monopolistic document and information centres disappear, and what will happen in the area of interlending and document supply? Will these functions survive in the electronic library?
The inverse approach with simple triangular shell elements for large strain predictions of sheet metal forming parts
Authors: Batoz Jean‐Louis , Qiao Guo Ying , Mercier Frederic
Published: July 2002

An efficient algorithm to estimate the large elasto‐plastic strains encountered in thin sheet metal forming parts has been continuously developed by the authors since 1987. The algorithm is based on a finite element discretization of the known final shape. In this paper a new simple triangular shell element with constant membrane and bending strains is presented using discrete Kirchhoff constraints. The expressions of the internal force vector and logarithmic strains through the thickness are derived. Two applications are considered to discuss the validity and efficiency of the numerical procedure.
Renewing the model employer
Authors: Stuart Mark , Martinez Lucio Miguel
Published: July 2002

Drawing from original empirical data this paper compares the changing nature of employment relations in the health and private sectors. A key concern is to assess the extent to which the emergence of partnership‐type arrangements between employers and trade unions lays the basis for the “renewal” of the traditional public sector concept of the model employer. Empirically, the paper draws on a survey of trade union representatives from 238 workplaces and a case study of a hospital trust. The data reveal that employment relations in the NHS are more collectivist when compared with the private sector. However, the development of partnership in the NHS is hamstrung by ongoing training and involvement gaps and widespread work intensification.
Entry into turbulent business networks ‐ The case of a Western company on the Estonian market
Authors: Salmi Asta
Published: July 2002

Adopts a holistic network approach to analyse a company’s entry into a turbulent market. The entry is examined as a process. The analysis focuses on the temporal context of business interaction; it inspects how the company copes with uncertainty, and proposes that the concept of a focal net be applied for strategic analysis of the context. In the empirical part, the Estonian market exemplifies a turbulent environment, and the entry process of one Western high‐technology company is analysed. It is concluded that, while all interaction on any business market involves elements of the historic background as well as the participants’ expectations of the future, history now seems to dominate the markets of Eastern Europe.
Can higher education match the information systems learning needs of SMEs?
Authors: Meldrum Mary , de Berranger Pascale
Published: July 2002

Discusses the problems of trying to match the information systems learning needs of small and medium sized enterprises (SMEs) to what higher education can offer. Most higher education institutions are directly trying to address the training needs of SMEs, spurred on by various Government initiatives. Much of the available funding is targeted at the introduction and development of new technologies in SMEs. The information systems education and training requirements of SMEs are reviewed and examined against the changing face of Higher Education. A series of studies was undertaken to examine the information systems learning needs of a small number of diverse SMEs. The results of these studies are discussed and compared with the outcomes of previous research into learning in SMEs and similarities and dissonances highlighted. The paper concludes with a discussion as to whether higher education can meet some of the information systems learning needs of SMEs.
Quasi‐variational inequality and shape optimization for solution of a free boundary problem
Authors: Abouchabaka J. , Aboulaïch R. , Nachaoui A. , Souissi A.
Published: July 2002

Electrical potentials in a junction field transistor can be calculated using a simplified model based on a complete depletion assumption. This gives rise to a free boundary problem. We show here how we can approximate this problem with a quasi‐variational inequality technique and the shape optimization method. A detailed analysis of these methods is presented. Using some numerical experiments we compare our results with the solution of the discrete drift‐diffusion system, accomplished with a Gummel‐like algorithm. The numerical results suggest that the methods proposed here work successfully and that the shape optimization technique provides a reasonably free boundary without excessive iterations.
An experiment on human sensory measurement and its objective measurement
Authors: Kawabata Sueo , Mori Miyuki , Niwa Masako
Published: July 2002

Presents a report on a recent experiment on the evaluation of seam pucker level by the objective method. Explains that human beings measure physical quantity and quality by means of subjective methods. Fabric hand evaluation is an example of this type of evaluation and an example of a relatively complex measurement with many relating physical variables. The measurement of seam pucker is a much simpler measurement than fabric hand evaluation, as only the fabric geometry along a seam line is visually observed and evaluated. This simplicity, however, is useful when investigating the human objective judgement of a geometrical phenomenon. Suggests that this investigation may be applied directly to the development of an objective system of seam pucker level.
Developing reflection and expertise: can mentors make the
difference?
Authors: Barnett Bruce G.
Published: July 2002

An important function of mentoring is to assist
protégés in becoming autonomous professionals who reflect
and solve problems as experts. The emerging literature on information
processing, reflective practice, and expertise indicates: experts solve
problems differently than novices; and learners who participate in a
structured instructional programme can learn these higher‐order
conceptual skills. Based on these findings, examines the principles and
practices of cognitive coaching as a viable means for mentors to use in
developing the reflective and problem‐solving expertise of their
protégés. Provides practical suggestions for how
mentor/coaches can utilize reflective questioning strategies, clarify
and probe responses, and take a non‐judgemental stance. Concludes with
an overview of a training model which would prepare and support mentors
in their attempt to assist protégés in becoming
self‐directed, expert problem solvers.
Observing educational administrators: paradoxical reflections
Authors: Beavis Allan K.
Published: July 2002

Self‐referential reflection inevitably reveals paradox. For some, paradox is a fruitful metaphor; for me, it raises problems that have epistemological implications. Traditionally paradox has been avoided by the problematic means of removing the observer from the domain of observation. Luhmann’s theory of autopoietic social systems offers an alternative manner of dealing with paradox. Such systems observe the self‐reference resulting from including an observer within the domain of observation and in their recursively closed operations combine other‐reference with every self‐reference. In this way, paradox is able to be "unfolded" in the operational moment. Luhmann’s social systems require, however, a radically different view of the place of the individual in society from that of traditional social theory – he or she does not belong!Communications are the elementary units for the social processing of meaning. This requires a radical revision of our concept of communication: it is communication that reproduces communication, not individuals.
Assuring quality and standards in globalised higher education
Authors: Yorke Mantz
Published: July 2002

Relates higher education to the labour market, noting that the pace of change in national and international economies requires higher education to encourage the development of people who can act effectively in turbulent circumstances. Shows that quality and standards are open to interpretations which depend upon the interpreter’s perspective. Argues that the extra‐institutional scrutiny of quality and standards is appropriate where higher education is expected to respond to national needs, but that the method used needs to be adapted to institutional context. Discusses the potential that ISO 9000, or an analogue, might have for an extra‐institutional quality assurance system that is economical in operation.
Student feedback systems in the Business School: a departmental model
Authors: King Malcolm , Morison Ian , Reed Gary , Stachow Grazyna
Published: July 2002

Feedback systems in the Loughborough University Business School operate in the context of a centralised university framework which provides guidelines, codes of practice, questionnaire templates and OMR equipment to read large quantities of forms. Informal feedback is encouraged and a system of course representatives and liaison committees is supported with help and training from the Students’ Union. These are supplemented by questionnaires at module, year and programme level, containing both central and departmental questions. The systems culminate in annual Programme Review Boards whose actions are reported back to students. With suitable safeguards, efforts at closing the loop encourage sufficient student confidence in the system for the results to be reliable and useful. Staff confidence is increased by involvement in the process although this can conflict with central requirements. However central support is crucial for success and Business Schools can resolve this dilemma by taking the lead in university developments.
Information technology in a university: a case study
Authors: Tellis Winston
Published: July 2002

Reports on a case study conducted at Fairfield University, USA, on the rapid increase in information technology implementation. The study replicated the work of Levy and extended it by examining aspects of the Internet, World Wide Web, and client/server computing. Survey instruments were the primary means of data collection, augmented by interviews and internal documents. The results show potentially large increases in expenditure ahead as users feel the need to use the new technology. Users, however rejected most of the listed sources of funds to pay for the increase in expenditure. Recommendations include more formal server capacity planning and configuration, and shorter information technology planning cycles.
A relationship‐building model for the Web retail marketplace
Authors: Wang Fang , Head Milena , Archer Norm
Published: July 2002

Electronic commerce has existed in the business‐to‐business marketplace since the 1970s, in forms such as electronic data interchange (EDI) and electronic funds transfer (EFT). With the emergence of the Internet, and the World Wide Web in particular, electronic commerce entered a new era which opened the door for an electronic business‐to‐consumer marketplace. Although the retail side of electronic commerce is still in its infancy, the Web medium offers great potential for building the customer‐base, promoting sales, and improving after‐sales service. Examines the concept of relationship marketing, which has caused a paradigm shift in business‐to‐business marketing during recent years. Extends the concepts of network marketing to the Web retail marketplace, and develops a market process model for Web retailing that outlines the stages of the relationship building process.
IT and university libraries in Africa
Authors: Rosenberg Diana
Published: July 2002

Based on the findings of a detailed review of the current state and future prospects of 19 university libraries in 12 countries of Africa undertaken in 1995, levels of adoption and benefits IT has brought to libraries are weighed against the drawbacks. Implications for practitioners and researchers are discussed. IT will not reduce the need for hard copy books and journals. Its biggest potential is in providing links to the outside world and in increasing intra‐African exchange and communication.
Going with the flow: Web sites and customer involvement
Authors: Nel Deon , van Niekerk Raymond , Berthon Jean‐Paul , Davies Tony
Published: July 2002

This paper investigates a structure of commercial Web sites, and then attempts to analyse various patterns that emerge which may be of future use as a guideline to businesses that intend establishing a Web presence. Key to the understanding of these patterns is a clearer grasp of the implications of human interaction with the new medium. The focus is on an experiential construct, namely flow, and how this might vary by Web site, and on using this to begin to unravel the secrets of good commercial Web site design and its implications for business.
Postmodern marketing: research issues for retail financial services
Authors: Dawes Jillian , Berman Brown Reva
Published: July 2002

Postmodern conditions and re‐evaluations of marketing theory are prompting a re‐consideration of marketing strategies and methodologies. This paper is concerned with research issues arising from these changes and uses the case of retailing financial services as an illustration. Groups of financial services customers, once assumed to be homogeneous, are proving to have individualised needs and are resisting conventional segmentation techniques. Behavioural consistency and orderliness are giving way to fragmentation and market instability in what is described as the postmodern era. Financial service retailers, structured, formalised and risk averse, may find that their preference for uniformity inhibits their ability to serve with diverse, evolving markets. A research agenda is proposed based on a juxtaposition of postmodern considerations and financial services retailing incorporating recent contributions to marketing thought.
Layer position accuracy in powder‐based rapid prototyping
Authors: Lee S.‐J.J. , Sachs E. , Cima M.
Published: July 2002

Emerging technologies commonly known as “rapid prototyping” fabricate solid objects directly from computer models by building parts in thin layers. Three‐dimensional printing is one such process that creates engineering prototypes and tooling by joining powder particles selectively on a layer‐by‐layer basis. The powder‐based approach offers tremendous flexibility in geometry and materials, but it makes layer position accuracy a fundamental concern for dimensional control in the vertical direction. Ideally, each powder layer is generated at a vertical position that remains fixed, at a prescribed distance with respect to a machine reference. However, compressive loads imparted to a stack of layers (by the weight of subsequent layers, for example) may cause the layers to displace downward. Develops a model for layer displacement using experimental data for compressibility and applied load. Compares predictions made from the model to measured displacements, and the predictions successfully captured the relative magnitudes of actual errors at various positions within layered powder beds. Position changes were most severe in the middle regions of the powder beds, with diminishing magnitude towards the top and bottom. Uses aluminium oxide powder in two different sizes (approximately of 10‐micron and 30‐micron diameter) and two different shapes (platelet and spherical) in the studies. The average measured displacement in a 76.2mm deep bed ranged from 23 microns for a 30‐micron platelet‐shaped powder to over 260 microns for a 9‐micron platelet‐shaped sample.
Material properties and fabrication parameters in selective laser sintering process
Authors: Gibson Ian , Shi Dongping
Published: July 2002

As part of a manufacturing system, rapid prototyping (RP) should be integrated with other manufacturing technologies. To ensure that this integration is successful and intelligent, it is necessary to understand and incorporate the properties of RP components. Selective laser sintering (SLS) is an important RP method because of its wide range of materials which can be used. The properties of different SLS powders influence the fabrication parameters in the process and these fabrication parameters in turn affect the mechanical properties of the resultant component. SLS components generally require post‐processing which can also affect the mechanical properties. To obtain optimum quality output, knowledge of the effects of sintering and post‐processing must be incorporated into design and process planning.
Evaluating the stability of the search tools Hotbot and Snap: a case study
Authors: Bar‐Ilan Judit
Published: July 2002

Discusses the results of a case study in which 20 random queries were presented for ten consecutive days to Hotbot and Snap, two search tools that draw their results from the database of Inktomi. The results show huge daily fluctuations in the number of hits retrieved by Hotbot, and high stability in the hits displayed by Snap. These findings are to alert users of Hotbot of its instability as of October 1999, and they raise questions about the reliability of previous studies estimating the size of Hotbot based on its overlap with other search engines.
3D domain swapping: As domains continue to swap
Authors: Liu Yanshun , Eisenberg David
Published: July 2002

Three‐dimensional (3D) domain swapping creates a bond between two or more protein molecules as they exchange their identical domains. Since the term '3D domain swapping' was first used to describe the dimeric structure of diphtheria toxin, the database of domain‐swapped proteins has greatly expanded. Analyses of the now about 40 structurally characterized cases of domain‐swapped proteins reveal that most swapped domains are at either the N or C terminus and that the swapped domains are diverse in their primary and secondary structures. In addition to tabulating domain‐swapped proteins, we describe in detail several examples of 3D domain swapping which show the swapping of more than one domain in a protein, the structural evidence for 3D domain swapping in amyloid proteins, and the flexibility of hinge loops. We also discuss the physiological relevance of 3D domain swapping and a possible mechanism for 3D domain swapping. The present state of knowledge leads us to suggest that 3D domain swapping can occur under appropriate conditions in any protein with an unconstrained terminus. As domains continue to swap, this review attempts not only a summary of the known domain‐swapped proteins, but also a framework for understanding future findings of 3D domain swapping.
TEM‐1 β‐lactamase as a scaffold for protein recognition and assay
Authors: Legendre Daniel , Vucic Bénédicte , Hougardy Vincent , Girboux Anne‐Lise , Henrioul Christophe , Van Haute Julien , Soumillion Patrice , Fastrez Jacques
Published: July 2002

A large number of different proteins or protein domains have been investigated as possible scaffolds to engineer antibody‐like molecules. We have previously shown that the TEM‐1 β‐lactamase can accommodate insertions of random sequences in two loops surrounding its active site without compromising its activity. From the libraries that were generated, active enzymes binding with high affinities to monoclonal antibodies raised against prostate‐specific antigen, a protein unrelated to β‐lactamase, could be isolated. Antibody binding was shown to affect markedly the enzyme activity. As a consequence, these enzymes have the potential to be used as signaling molecules in direct or competitive homogeneous immunoassay. Preliminary results showed that β‐lactamase clones binding to streptavidin could also be isolated, indicating that some enzymes in the libraries have the ability to recognize proteins other than antibodies. In this paper, we show that, in addition to β‐lactamases binding to streptavidin, β‐lactamase clones binding to horse spleen ferritin and β‐galactosidase could be isolated. Affinity maturation of a clone binding to ferritin allowed obtaining β‐lactamases with affinities comprised between 10 and 20 nM (Kd) for the protein. Contrary to what was observed for β‐lactamases issued from selections on antibodies, enzyme complexation induced only a modest effect on enzyme activity, in the three cases studied. This kind of enzyme could prove useful in replacement of enzyme‐conjugated antibodies in enzyme‐linked immunosorbant assays (ELISA) or in other applications that use antibodies conjugated to an enzyme.
Identification of intrinsic order and disorder in the DNA repair protein XPA
Authors: Iakoucheva Lilia M. , Kimzey Amy L. , Masselon Christophe D. , Bruce James E. , Garner Ethan C. , Brown Celeste J. , Dunker A. Keith , Smith Richard D. , Ackerman Eric J.
Published: July 2002

The DNA‐repair protein XPA is required to recognize a wide variety of bulky lesions during nucleotide excision repair. Independent NMR solution structures of a human XPA fragment comprising approximately 40% of the full‐length protein, the minimal DNA‐binding domain, revealed that one‐third of this molecule was disordered. To better characterize structural features of full‐length XPA, we performed time‐resolved trypsin proteolysis on active recombinant Xenopus XPA (xXPA). The resulting proteolytic fragments were analyzed by electrospray ionization interface coupled to a Fourier transform ion cyclotron resonance mass spectrometry and SDS‐PAGE. The molecular weight of the full‐length xXPA determined by mass spectrometry (30922.02 daltons) was consistent with that calculated from the sequence (30922.45 daltons). Moreover, the mass spectrometric data allowed the assignment of multiple xXPA fragments not resolvable by SDS‐PAGE. The neural network program Predictor of Natural Disordered Regions (PONDR) applied to xXPA predicted extended disordered N‐ and C‐terminal regions with an ordered internal core. This prediction agreed with our partial proteolysis results, thereby indicating that disorder in XPA shares sequence features with other well‐characterized intrinsically unstructured proteins. Trypsin cleavages at 30 of the possible 48 sites were detected and no cleavage was observed in an internal region (Q85‐I179) despite 14 possible cut sites. For the full‐length xXPA, there was strong agreement among PONDR, partial proteolysis data, and the NMR structure for the corresponding XPA fragment.
Characterization of apo and partially saturated states of calerythrin, an EF‐hand protein from S. erythraea: A molten globule when deprived of Ca2+
Authors: Aitio Helena , Laakso Tero , Pihlajamaa Tero , Torkkeli Mika , Kilpeläinen Ilkka , Drakenberg Torbjörn , Serimaa Ritva , Annila Arto
Published: July 2002

Calerythrin, a four‐EF‐hand calcium‐binding protein from Saccharopolyspora erythraea, exists in an equilibrium between ordered and less ordered states with slow exchange kinetics when deprived of Ca2+ and at low temperatures, as observed by NMR. As the temperature is raised, signal dispersion in NMR spectra reduces, and intensity of near‐UV CD bands decreases. Yet far‐UV CD spectra indicate only a small decrease in the amount of secondary structure, and SAXS data show that no significant change occurs in the overall size and shape of the protein. Thus, at elevated temperatures, the equilibrium is shifted toward a state with characteristics of a molten globule. The fully structured state is reached by Ca2+‐titration. Calcium first binds cooperatively to the C‐terminal sites 3 and 4 and then to the N‐terminal site 1, which is paired with an atypical, nonbinding site 2. EF‐hand 2 still folds together with the C‐terminal half of the protein, as deduced from the order of appearance of backbone amide cross peaks in the NMR spectra of partially Ca2+‐saturated states.
Differentiation of the slow‐binding mechanism for magnesium ion activation and zinc ion inhibition of human placental alkaline phosphatase
Authors: Hung Hui‐Chih , Chang Gu‐Gang
Published: July 2002

The binding mechanism of Mg2+ at the M3 site of human placental alkaline phosphatase was found to be a slow‐binding process with a low binding affinity (KMg(app.) = 3.32 mM). Quenching of the intrinsic fluorescence of the Mg2+‐free and Mg2+‐containing enzymes by acrylamide showed almost identical dynamic quenching constant (Ksv = 4.44 ± 0.09 M−1), indicating that there is no gross conformational difference between the M3‐free and the M3‐Mg2+ enzymes. However, Zn2+ was found to have a high affinity with the M3 site (KZn(app.) = 0.11 mM) and was observed as a time‐dependent inhibitor of the enzyme. The dependence of the observed transition rate from higher activity to lower activity (kobs) at different zinc concentrations resulted in a hyperbolic curve suggesting that zinc ion induces a slow conformational change of the enzyme, which locks the enzyme in a conformation (M3′‐Zn) having an extremely high affinity for the Zn2+ (K*Zn(app.) = 0.33 μM). The conformation of the M3′‐Zn enzyme, however, is unfavorable for the catalysis by the enzyme. Both Mg2+ activation and Zn2+ inhibition of the enzyme are reversible processes. Structural information indicates that the M3 site, which is octahedrally coordinated to Mg2+, has been converted to a distorted tetrahedral coordination when zinc ion substitutes for magnesium ion at the M3 site. This conformation of the enzyme has a small dynamic quenching constant for acrylamide (Ksv = 3.86 ± 0.04 M−1), suggesting a conformational change. Both Mg2+ and phosphate prevent the enzyme from reaching this inactive structure. GTP plays an important role in reactivating the Zn‐inhibited enzyme activity. We propose that, under physiological conditions, magnesium ion may play an important modulatory role in the cell for protecting the enzyme by retaining a favorable geometry of the active site needed for catalysis.
Effects of molecular crowding by saccharides on α‐chymotrypsin dimerization
Authors: Patel Chetan N. , Noble Schroeder M. , Weatherly Gresham T. , Tripathy Ashutosh , Winzor Donald J. , Pielak Gary J.
Published: July 2002

Given the importance of protein complexes as therapeutic targets, it is necessary to understand the physical chemistry of these interactions under the crowded conditions that exist in cells. We have used sedimentation equilibrium to quantify the enhancement of the reversible homodimerization of α‐chymotrypsin by high concentrations of the osmolytes glucose, sucrose, and raffinose. In an attempt to rationalize the osmolyte‐mediated stabilization of the α‐chymotrypsin homodimer, we have used models based on binding interactions (transfer‐free energy analysis) and steric interactions (excluded volume theory) to predict the stabilization. Although transfer‐free energy analysis predicts reasonably well the relatively small stabilization observed for complex formation between cytochrome c and cytochrome c peroxidase, as well as that between bobtail quail lysozyme and a monoclonal Fab fragment, it underestimates the sugar‐mediated stabilization of the α‐chymotrypsin dimer. Although predictions based on excluded volume theory overestimate the stabilization, it would seem that a major determinant in the observed stabilization of the α‐chymotrypsin homodimer is the thermodynamic nonideality arising from molecular crowding by the three small sugars.
Increasing protein stability using a rational approach combining sequence homology and structural alignment: Stabilizing the WW domain
Authors: Jiang Xin , Kowalski Jennifer , Kelly Jeffery W.
Published: July 2002

This study shows that a combination of sequence homology and structural information can be used to increase the stability of the WW domain by 2.5 kcal mol−1and increase the Tmby 28°C. Previous homology‐based protein design efforts typically investigate positions with low sequence identity, whereas this study focuses on semi‐conserved core residues and proximal residues, exploring their role(s) in mediating stabilizing interactions on the basis of structural considerations. The A20R and L30Y mutations allow increased hydrophobic interactions because of complimentary surfaces and an electrostatic interaction with a third residue adjacent to the ligand‐binding hydrophobic cluster, increasing stability significantly beyond what additivity would predict for the single mutations. The D34T mutation situated in a π‐turn possibly disengages Asn31, allowing it to make up to three hydrogen bonds with the backbone in strand 1 and loop 2. The synergistic mutations A20R/L30Y in combination with the remotely located mutation D34T add together to create ahYap WW domain that is significantly more stable than any of the protein structures on which the design was based (Pin and FBP28 WW domains).