bluuebunny/crossref_metadata_2025 huggingface dataset:
Tobacco Transgenic Lines That Express Fenugreek Galactomannan Galactosyltransferase Constitutively Have Structurally Altered Galactomannans in Their Seed Endosperm Cell Walls
Authors: Reid J.S. Grant , Edwards Mary E. , Dickson Cathryn A. , Scott Catherine , Gidley Michael J.
Published: March 2003

Galactomannans [(1→6)-α-d-galactose (Gal)-substituted (1→4)-β-d-mannans] are major cell wall storage polysaccharides in the endosperms of some seeds, notably the legumes. Their biosynthesis in developing legume seeds involves the functional interaction of two membrane-bound glycosyltransferases, mannan synthase (MS) and galactomannan galactosyltransferase (GMGT). MS catalyzes the elongation of the mannan backbone, whereas GMGT action determines the distribution and amount of Gal substitution. Fenugreek (Trigonella foenum-graecum) forms a galactomannan with a very high degree of Gal substitution (Man/Gal = 1.1), and its GMGT has been characterized. We now report that the endosperm cell walls of the tobacco (Nicotiana tabacum) seed are rich in a galactomannan with a very low degree of Gal substitution (Man/Gal about 20) and that its depositional time course is closely correlated with membrane-bound MS and GMGT activities. Furthermore, we demonstrate that seeds from transgenic tobacco lines that express fenugreek GMGT constitutively in membrane-bound form have endosperm galactomannans with increased average degrees of Gal substitution (Man/Gal about 10 in T1 generation seeds and about 7.5 in T2generation seeds). Membrane-bound enzyme systems from transgenic seed endosperms form galactomannans in vitro that are more highly Gal substituted than those formed by controls under identical conditions. To our knowledge, this is the first report of structural manipulation of a plant cell wall polysaccharide in transgenic plants via a biosynthetic membrane-bound glycosyltransferase.
Nylon Filter Arrays Reveal Differential Gene Expression in Proteoid Roots of White Lupin in Response to Phosphorus Deficiency
Authors: Uhde-Stone Claudia , Zinn Kelly E. , Ramirez-Yáñez Mario , Li Aiguo , Vance Carroll P. , Allan Deborah L.
Published: March 2003

White lupin (Lupinus albus) adapts to phosphorus deficiency (−P) by the development of short, densely clustered lateral roots called proteoid (or cluster) roots. In an effort to better understand the molecular events mediating these adaptive responses, we have isolated and sequenced 2,102 expressed sequence tags (ESTs) from cDNA libraries prepared with RNA isolated at different stages of proteoid root development. Determination of overlapping regions revealed 322 contigs (redundant copy transcripts) and 1,126 singletons (single-copy transcripts) that compile to a total of 1,448 unique genes (unigenes). Nylon filter arrays with these 2,102 ESTs from proteoid roots were performed to evaluate global aspects of gene expression in response to −P stress. ESTs differentially expressed in P-deficient proteoid roots compared with +P and −P normal roots include genes involved in carbon metabolism, secondary metabolism, P scavenging and remobilization, plant hormone metabolism, and signal transduction.
crinkle, a Novel Symbiotic Mutant That Affects the Infection Thread Growth and Alters the Root Hair, Trichome, and Seed Development in Lotus japonicus
Authors: Tansengco Myra L. , Hayashi Makoto , Kawaguchi Masayoshi , Imaizumi-Anraku Haruko , Murooka Yoshikatsu
Published: March 2003

To elucidate the mechanisms involved inRhizobium-legume symbiosis, we examined a novel symbiotic mutant, crinkle (Ljsym79), from the model legume Lotus japonicus. On nitrogen-starved medium, crinkle mutants inoculated with the symbiont bacterium Mesorhizobium loti MAFF 303099 showed severe nitrogen deficiency symptoms. This mutant was characterized by the production of many bumps and small, white, uninfected nodule-like structures. Few nodules were pale-pink and irregularly shaped with nitrogen-fixing bacteroids and expressing leghemoglobin mRNA. Morphological analysis of infected roots showed that nodulation incrinkle mutants is blocked at the stage of the infection process. Confocal microscopy and histological examination ofcrinkle nodules revealed that infection threads were arrested upon penetrating the epidermal cells. Starch accumulation in uninfected cells and undeveloped vascular bundles were also noted incrinkle nodules. Results suggest that theCrinkle gene controls the infection process that is crucial during the early stage of nodule organogenesis. Aside from the symbiotic phenotypes, crinkle mutants also developed morphological alterations, such as crinkly or wavy trichomes, short seedpods with aborted embryos, and swollen root hairs.crinkle is therefore required for symbiotic nodule development and for other aspects of plant development.
Transgenic Studies on the Involvement of Cytokinin and Gibberellin in Male Development
Authors: Huang Shihshieh , Cerny R. Eric , Qi Youlin , Bhat Deepti , Aydt Carrie M. , Hanson Doris D. , Malloy Kathleen P. , Ness Linda A.
Published: March 2003

Numerous plant hormones interact during plant growth and development. Elucidating the role of these various hormones on particular tissue types or developmental stages has been difficult with exogenous applications or constitutive expression studies. Therefore, we used tissue-specific promoters expressing CKX1 andgai, genes involved in oxidative cytokinin degradation and gibberellin (GA) signal transduction, respectively, to study the roles of cytokinin and GA in male organ development. Accumulation of CKX1 in reproductive tissues of transgenic maize (Zea mays) resulted in male-sterile plants. The male development of these plants was restored by applications of kinetin and thidiazuron. Similarly, expression of gai specifically in anthers and pollen of tobacco (Nicotiana tabacum) and Arabidopsis resulted in the abortion of these respective tissues. Thegai-induced male-sterile phenotype exhibited by the transgenic plants was reversible by exogenous applications of kinetin. Our results provide molecular evidence of the involvement of cytokinin and GA in male development and support the hypothesis that the male development is controlled in concert by multiple hormones. These studies also suggest a potential method for generating maintainable male sterility in plants by using existing agrochemicals that would reduce the expense of seed production for existing hybrid crops and provide a method to produce hybrid varieties of traditionally non-hybrid crops.
Mapping the Proteome of Barrel Medic (Medicago truncatula),
Authors: Watson Bonnie S. , Asirvatham Victor S. , Wang Liangjiang , Sumner Lloyd W.
Published: March 2003

A survey of six organ-/tissue-specific proteomes of the model legume barrel medic (Medicago truncatula) was performed. Two-dimensional polyacrylamide gel electrophoresis reference maps of protein extracts from leaves, stems, roots, flowers, seed pods, and cell suspension cultures were obtained. Five hundred fifty-one proteins were excised and 304 proteins identified using peptide mass fingerprinting and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Nanoscale high-performance liquid chromatography coupled with tandem quadrupole time-of-flight mass spectrometry was used to validate marginal matrix-assisted laser desorption ionization time-of-flight mass spectrometry protein identifications. This dataset represents one of the most comprehensive plant proteome projects to date and provides a basis for future proteome comparison of genetic mutants, biotically and abiotically challenged plants, and/or environmentally challenged plants. Technical details concerning peptide mass fingerprinting, database queries, and protein identification success rates in the absence of a sequenced genome are reported and discussed. A summary of the identified proteins and their putative functions are presented. The tissue-specific expression of proteins and the levels of identified proteins are compared with their related transcript abundance as quantified through EST counting. It is estimated that approximately 50% of the proteins appear to be correlated with their corresponding mRNA levels.
In Vivo Gas Exchange Measurement of the Site and Dynamics of Nitrate Reduction in Soybean
Authors: Cen Yan-Ping , Layzell David B.
Published: March 2003

A gas analysis system was built to study the relationship between the reductant cost of NO3  − assimilation and the measured rate of CO2 and O2 exchange in roots, leaves, and stems+ petioles of soybean (Glycine max L. Merr. cv Maple glen) plants. The measurements were used to calculate the diverted reductant utilization rate (DRUR = 4*[measured rate of CO2 + measured rate of O2], in moles of high-energy electron [e  −] per gram per hour) in plants in the presence (N+) and absence (N−) of NO3  −. The differences in DRUR between the N+ and N− treatments provided a measure of the NO3  −-coupled DRUR of 25-d-old plants, whereas a 15NO3  −-enriched nutrient solution was used to obtain an independent measure of the rate of NO3  − assimilation. The measured reductant cost for the whole plant was 9.6 e  − per N assimilated, a value within the theoretical range of four to 10e  − per N assimilated. The results predicted that shoots accounted for about 55% of the whole-plant NO3  − assimilation over the entire day, with shoots dominating in the light, and roots in the dark. The gas analysis approach described here holds promise as a powerful, noninvasive tool to study the regulation of NO3  − assimilation in plant tissue.
E‐commerce marketing: fad or fiction? Management competency in mastering emerging technology. An international case analysis in the UAE
Authors: Darby Roger , Jones James , Al Madani Ghada
Published: March 2003

Considers the fundamental role of marketing within the dynamics of e‐commerce and addresses three key issues which challenge the concept of marketing when companies are faced with managing and utilising e‐commerce. First, is Internet marketing a “fad”? Second, if Internet marketing is viewed more broadly, does it provide an effective marketing tool for organisations? Third, does e‐commerce present a “new marketing paradigm”? Poses questions about the relevant skills that marketing managers need for effective marketing on the Internet. Questions whether these changes are IT or customer driven and the consequences for management development. To support the analysis of the effects of these changes, a preliminary study was undertaken in four different industrial sectors, involving four international companies based, or with main offices, in the United Arab Emirates. Semi‐structured interviews were undertaken with marketing managers to address the key issues.
An applied model for improving inventory management in ERP systems
Authors: Razi Muhammad A. , Tarn J. Michael
Published: March 2003

Enterprise resource planning (ERP) systems provide functions to calculate safety stock (SS), make demand forecast and determine reorder point (ROP) for each item contained in the database based on the item’s demand history. Most ERP systems are ill‐equipped to deal with the demand of slow moving items such as spare parts. Based on data from a Fortune 500 company, presents the development and evaluation of a spare parts inventory control model. Compares the proposed model with the results achieved using the forecasting and inventory management modules of a popular ERP system. Tested with computer simulation, the proposed model significantly outperforms the commercial ERP model on both measures of service level and expected total annual cost.
An online decision support system for transportation mode choice
Authors: Vannieuwenhuyse B. , Gelders L. , Pintelon L.
Published: March 2003

Because of growing congestion problems and environmental and safety considerations, freight transportation becomes more and more a key issue in logistics in particular and in the industrial process in general. The transportation mode choice is still often made in a rather irrational way. This paper presents the outcome of surveys conducted in Belgian industry about the logistics decision maker’s perception concerning the transportation modes. The different choice criteria are determined and weighted. Finally an interactive Internet tool is presented in order to support the transportation mode decision process. The paper provides insights into the logistics process to the authorities, but above all offers a tool to individual decision makers in the transportation mode selection.
Management context and impact of e‐commerce in the Greek food industries
Authors: Papathanassiou Eleutherios , Arkoumani Barbara , Kardaras Dimitrios
Published: March 2003

Increased competition characterises the food sector worldwide, but the potential of e‐commerce (eC) to improve customer satisfaction in the food industries has not been thoroughly studied. Reports on the results of a survey of 48 information systems (IS) and marketing managers from food companies in Greece. Examines the eC management context and investigates how the Internet can offer new opportunities for improving customer satisfaction. The results show that there is potential for customer‐oriented eC applications across the value chain.
Information management and knowledge integration for enterprise innovation
Authors: Badii Atta , Sharif Amir
Published: March 2003

The key trends in emerging ICT integration choices for cost‐effective, flexible knowledge integration, work‐flow‐embedded evaluation and eCRM‐driven value innovation are examined. Enterprise knowledge integration initiatives can create socio‐technical and cultural tensions as well as possible straitjacketing of business process architectures thus suppressing responsive business re‐engineering and causing loss of competitive advantage for some companies. A framework, C‐assure, is presented for optimising knowledge integration, impact analysis and evaluation to support innovation throughout the various interacting enterprise lifecycles.
An empirical study of critical factors of TQM in Palestinian organizations
Authors: Baidoun Samir
Published: March 2003

This paper presents the results of a questionnaire survey to investigate factors of quality that are absolutely essential for successful implementation in Palestinian organizations. Out of a possible list of 78 names of organizations, 78 were targeted, with 78 usable questionnaires returned, thus giving a response rate of 100 per cent. The analysis led to the development of a criticality quality factor structure, comprising 19 factors sorted in descending order of criticality through three tiers. All of the factors were found to be supported by similar studies and quoted literatures.
Lodging quality index (LQI): assessing customers’ perceptions of quality delivery
Authors: Getty Juliet M. , Getty Robert L.
Published: March 2003

No matter how much effort is placed into producing quality service, the true test lies in the perception of customers. To assess this perception, lodging executives have only a few quantitative instruments available from which to choose, since the development of such scales is still in its infancy. This study takes the reader through the step‐by‐step development of a reliable and valid quantitative measuring tool that lodging practitioners can implement to measure their customers’ perception of delivered quality. The procedures followed begin with the same original dimensions that were used to develop SERVQUAL. The resulting lodging quality index (LQI) emphasizes five clearly defined dimensions of service quality.
The effects of density extremum and rotation on the onset of thermal instability
Authors: Pascal J.P. , D'Alessio S.J.D.
Published: March 2003

This paper addresses the onset of Be´nard convection on a rotating horizontally confined layer of water near the temperature of maximum density that is heated from below. A quadratic relation between temperature and density is assumed near the density extremum. A linear stability analysis is employed to determine the critical conditions for the onset of thermal instability. The resulting eigenvalue problem is numerically solved by expanding the amplitudes of the temperature and velocity perturbations in a truncated eigenfunction and power series. The validity of the principle of exchange of stabilities is proved analytically for a certain case and numerically investigated in general. Plots of the marginal stability curves as well as the variation of the critical Rayleigh number with other dimensionless parameters which naturally arise in the problem are also presented and discussed.
Heat transfer to pulsating turbulent flow in an abrupt pipe expansion
Authors: Said S.A.M. , Habib M.A. , Iqbal M.O.
Published: March 2003

A numerical investigation aimed at understanding the flow and heat transfer characteristics of pulsating turbulent flow in an abrupt pipe expansion was carried out. The flow patterns are classified by four parameters; the Reynolds number, the Prandtl number, the abrupt expansion ratio and the pulsation frequency. The influence of these parameters on the flow was studied in the range 104<Re<5×104, 0.7<Pr<7.0, 0.2<d/D<0.6 and 5<f<35. It was found that the influence of pulsation on the mean time‐averaged Nusselt number is insignificant (around 10 per cent increase) for fluids having a Prandtl number less than unity. This effect is appreciable (around 30 per cent increase) for fluids having Prandtl number greater than unity. For all pulsation frequencies, the variation in the mean time‐averaged Nusselt number, maximum Nusselt number and its location with Reynolds number and diameter ratio exhibit similar characteristics to steady flows.
3D numerical simulation of on ground Marangoni flow instabilities in liquid bridges of low Prandtl number fluid
Authors: Lappa M. , Yasushiro S. , Imaishi N.
Published: March 2003

The influence of gravity on the Marangoni flow instability in half zone liquid bridges in the case of liquid metals is investigated by direct 3D and time‐dependent simulation of the problem. The computations are carried out for different heating conditions and environments (zero g conditions and on ground liquid zone heated from above or from below). The case of cylindrical shape (simplified model) and of melt/air interface deformed by the effect of gravity (real conditions) are considered. The comparison among these situations gives insight into the separate (gravity) effects of buoyancy forces and of the free surface deviation with respect to straight configuration. Body‐fitted curvilinear co‐ordinates are adopted to handle the non‐cylindrical problem. The liquid bridge exhibits different behaviours according to the allowed bridge shape. If the shape is forced to be cylindrical, the flow field is stabilized in the case of heating from above and destabilized if gravity is reversed. If the deformation is taken into account, gravity always stabilizes the Marangoni flow regardless of its direction (parallel or antiparallel to the axis) and the 3D flow structure is different according to the heating condition (from above or from below). In the latter case, the critical Marangoni number is larger and the critical wave number is smaller, compared with the opposite condition. In addition, for Pr=0.02 (Gallium), a surprising heretofore unseen behaviour arises. No steady bifurcation occurs and the flow becomes unstable directly to oscillatory disturbances. This phenomenon has never been reported before in the case of low Prandtl number liquids.
Bioconvection of negatively geotactic microorganisms in a porous medium: the effect of cell deposition and declogging
Authors: Kuznetsov A.V. , Jiang N.
Published: March 2003

Mechanisms of deposition and declogging are considered while formulating a new continuum model for bioconvection in a dilute suspension of motile, negatively geotactic microorganisms in a porous medium. According to research in 1988, bioconvection is the name given to pattern‐forming convective motions set up in suspensions of swimming microorganisms. “Negative geotaxis” means that the microorganisms tend to swim against the gravitational force. This paper is motivated by experimental research by Kessler who investigated the effect of porous media on the development of convection instability in algal suspensions. In the model suggested in this paper, the decrease of permeability due to cell adsorption by the porous medium is considered and the influence of this permeability decrease on the development of bioconvection is studied. The existence and stability of a two‐dimensional plume in a rectangular enclosure with stress‐free sidewalls is investigated. Governing equations include the Darcy law as well as the microorganism conservation equations. A conservative finite‐difference scheme is utilized to solve these equations numerically. The analysis of the proposed model reveals that the major factors affecting the development of bioconvection are the initial permeability of the porous medium and the rate of cell deposition. For small permeability, the resistance to the fluid flow is too large, and bioconvection does not develop. If the rate of cell deposition is too large, the number of suspended cells quickly becomes too small because of cell capturing by the porous medium. For this reason, the critical density difference in the top fluid layer cannot be reached, and bioconvection does not develop.
Linear feedback control for convection‐diffusion
Authors: Kavouklis Christos , Carey Graham F.
Published: March 2003

This study is concerned with linear feedback control in finite element modeling of transient convection‐diffusion in an incompressible fluid. Our aim is to introduce a linear feedback that solves the corresponding tracking problem for any sufficiently smooth target temperature field. The control aspects are discussed and we summarize convergence results. Numerical results for a test problem are included to illustrate the approach.
Numerical model for vacuum infusion manufacturing of polymer composites
Authors: Magnus Andersson H. , Staffan Lundström T. , Rikard Gebart B.
Published: March 2003

The focus is set on the development and evaluation of a numerical mgodel describing the impregnation stage of a method to manufacture fibre reinforced polymer composites, namely the vacuum infusion process. Examples of items made with this process are hulls to sailing yachts and containers for the transportation industry. The impregnation is characterised by a full 3D flow in a porous medium having an anisotropic, spatial‐ and time‐dependent permeability. The numerical model has been implemented in a general and commercial computational fluid dynamic software through custom written subroutines that: couple the flow equations to the equations describing the stiffness of the fibre reinforcement; modify the momentum equations to account for the porous medium flow; remesh the computational domain in each time step to account for the deformation by pressure change. The verification of the code showed excellent agreement with analytical solutions and very good agreement with experiments. The numerical model can easily be extended to more complex geometry and to other constitutive equations for the permeability and the compressibility of the reinforcement.
A community development approach to tobacco control
Authors: Black Margaret , McKie Linda , Allen Elaine
Published: March 2003

This article considers the work of an adult education project, second chance learning (SCL), in helping its clients not only to try to stop smoking, but also to examine the place of tobacco in their lives. SCL undertook this work as one of three projects funded by the Argyll and Clyde Health Board in response to the 1998 publication of Smoking Kills, by the Department of Health. SCL is based in a relatively deprived area and has a strong tradition of working with (rather than for) its users, within a clear and open management structure. The activities of the tobacco group were determined by its members, and the success of the group was marked not only by the fact that some members did manage to stop smoking, but also that members felt they had a better understanding of why they smoked. Higher levels of self confidence were evidenced by the increasing diversity of the activities undertaken by the group.
Teacher attitudes towards health education in Greek‐speaking Cyprus schools
Authors: Apostolidou Martha , Fontana David
Published: March 2003

In light of expert opinion that health education should be integrated into the school curriculum, rather than taught only as a separate unit, it is desirable that all teachers have adequate knowledge and understanding of the subject. The present research investigated attitudes of a representative sample of Greek Cypriot serving teachers towards health education, together with their views on related matters such as the value of contributions from outside bodies and the availability of finance and resources. Results suggest that teachers are generally very positive towards health education, but regard initial and in‐service training provision as inadequate and causing manifest confusion in their understanding of many key issues. Implications emerge for future teacher training programmes.
An evaluation of a drug education play for schools in south Wales
Authors: Macdonald Gordon , Nehammer Sarah
Published: March 2003

Schools are often seen as a key setting for health education and health promotion. Theatre in education offers a valuable way of tackling difficult subjects within schools, particularly for those children open to risk and lifestyle choices. This paper reports on a play about drugs, written and acted by a local theatre in education group in south Wales. The play was written for 10‐12 year olds and has been performed, with revisions, over the last ten years in local schools. This paper reports on a simple evaluation of the effects of the play on the understanding of, and feelings about, drugs in the target group exposed to the play. A total of 133 children responded to the survey and were generally positive about the play, identified with the main characters and could remember some of the illicit drugs mentioned in the drama. Six teachers were also questioned and they were positive about the play’s contribution to the curriculum and its approach to drug education.
Key informant representations of Maori and other patient fears of accessing general practitioner care for child asthma in Auckland, New Zealand
Authors: Buetow Stephen , Adair Vivienne , Coster Gregor , Hight Makere , Gribben Barry , Mitchell Ed
Published: March 2003

Fear is seldom reported in the research literature on barriers to accessing general practitioner (GP) care. One reason may be that some patients are unwilling to admit to fear of this care. This is especially so for patients who, for social, cultural and historical reasons, have a poor sense of self, or do not wish to challenge professionals, or both. In New Zealand, the Maori and Pacific peoples are disproportionately characteristic of these patients and have poor access to GP care, including asthma in children. This paper contributes to the literature on using key informants to interpret another group’s needs, and integrates and adds to known patient attitudes that can hinder access to GP services.
Increasing fruit and vegetable consumption among British primary schoolchildren: a review
Authors: Burchett Helen
Published: March 2003

This paper aimed to identify the key elements that should be included in a fruit and vegetable‐promoting programme in British primary schools. Such a programme could be used in healthy schools schemes or “five‐a‐day” programmes. Five US school intervention studies were analysed to identify their most effective elements. Four of the five studies found that their intervention had a significant effect on fruit and vegetable consumption. All the studies were behaviourally focussed and used interactive teaching methods and were based on social cognitive theory. Targeting fruit and vegetable consumption appeared to be more effective than broader lifestyle/healthy eating interventions. All studies, except one, increased the availability of fruit and vegetables at school lunches but none increased their availability at snack times and breakfast. Three studies taught preparation skills. All included taste testing activities which aim to increase familiarity and so increase taste preferences. Four used role models to promote fruit and vegetables and two gave rewards for consumption. One study attempted to improve the sensory properties of fruit and vegetables at lunch through preparation techniques. Two studies included a community involvement component and four involved families in the intervention. Results from two of the studies showed that interventions must be maintained over time if effects are to be maintained. Greater effects were seen for fruit consumption than vegetable consumption except for one study which focussed specifically on vegetables.
Empowering schools: translating health promotion principles into practice
Authors: Scriven Angela , Stiddard Liz
Published: March 2003

Although schools are highly appropriate arenas for promoting health, in England they have hierarchical cultures, limited autonomy and a dominant academic function that can inhibit the adoption of empowerment approaches. Centred on an English perspective, this article presents a broad examination of the concept of empowerment and considers the implication this may have to schools. Aspects of personal empowerment, including the development of psychological and personal competencies, will be discussed alongside questions surrounding access to power at both the levels of the individual and the community. Ethical issues, such as freedom of action versus control, will also be addressed. The outcome of this analysis is a set of recommended practices which individual schools could adopt to encourage a more empowering environment for young people.
Issues relating to learning accreditation in corporate university management
Authors: Dealtry Richard
Published: March 2003

This article considers the role of learning validation and accreditation systems in relation to the demand for more co‐creative quality assurance solutions in corporate and organisational learning management. It explores the need to emphasise the organisational demand side in the management of quality new learning by applying a more holistic development perspective. It looks at the subject of credit frameworks from the point of view of both providers and consumers of learning programmes and develops a more radical four dimensional management perspective that extends the reach of considerations beyond the two dimensions of academic and professional practice. It introduces a leadership‐inspired career‐based accreditation system that engages with the middle and upper tiers in organisational learning. It provides this as a basis for developing a methodology and a forward thinking guideline for learning portfolio practice and quality assurance accreditation management in the organisational setting.
The theory and practice of workplace learning in the adoption of integrated pest management by tropical fruit growers in Thailand
Authors: Elsey Barry , Sirichoti Kittipong
Published: March 2003

Integrated pest management (IPM) is a well‐known innovation that accords with modern environmental management “best practice”. In this paper it is examined as an example of the theory and practice underpinning workplace learning and andragogy. Particular attention is focused on the role of agricultural extension workers (AEWs) as learning facilitators in a non‐formal setting. As contextual background, a recent IPM diffusion project in a region of Thailand, where durian is extensively grown, as a process of innovation adoption is outlined. In sum, the intelligent way IPM knowledge was transferred, though the mediating role of AEWs reflected the current emphasis on collaborative partnerships in “real‐life” workplace learning contexts as an effective means of managing change in complex environments.
A review of action learning literature 1994‐2000: Part 1 – bibliography and comments
Authors: Smith Peter A.C. , O’Neil Judy
Published: March 2003

Many organizations now utilize action learning, and it is applied increasingly throughout the world. Action learning appears in numerous variants, but generically it is a form of learning through experience, “by doing”, where the task environment is the classroom, and the task the vehicle. Two previous reviews of the action learning literature by Alan Mumford respectively covered the field prior to 1985 and the period 1985‐94. Both reviews included books as well as journal articles. This current review covers the period 1994‐2000 and is limited to publicly available journal articles.
Policy makers, information and learning
Authors: Beers Pieter J. , van Asselt Marjolein B.A. , Vermunt Jan D. , Kirschner Paul A.
Published: March 2003

To gain insight in how policy makers work and learn, in‐depth interviews were held with seven Dutch policy makers working on global sustainability issues. The focus of the interview was on the information needs, information gathering practices, and working styles of the policy makers. Our results indicate that policy makers have a strong need for information on linkages between different policy problems, and on different cultural perspectives on those problems. Information gathering is marked by an emphasis on information filtering towards the policy issue at hand. Finally, policy makers appear to be predisposed to an application‐oriented working style. The combination of an application‐oriented working style with a policy‐driven search for information seems inadequate for satisfying policy makers’ information needs. Current learning practices among policy makers appear to be inadequate for coping with complexity.
Bridging the gap in support for ethnic minority owned businesses: the case of Devon and Cornwall
Authors: Baldock Robert , Smallbone David
Published: March 2003

This paper presents findings from recent research undertaken into the characteristics and support needs of ethnic minority owned businesses (EMBs) in Devon and Cornwall. The study was commissioned by PROSPER (formerly Devon and Cornwall TEC and Business Link), in collaboration with the Rural Race Equality Project in South West England. EMBs have been the subject of growing interest from a variety of sources in recent years, generating considerable debate about their distinctiveness in comparison with other small firms and their needs in terms of public policy. Not surprisingly, perhaps, a great deal of this research has focused on areas where EMBs are concentrated, such as London and Birmingham. In contrast, this research focuses on EMBs in an area which is some distance from the main centres of EMB concentration and where the ethnic minority population is more dispersed, many in a rural context.
Corporate debt policy of small firms: an empirical (re)examination
Authors: Paulo Esperança José , Matias Gama Ana Paula , Azzim Gulamhussen Mohamed
Published: March 2003

The capital structure decision can be considered a difficult problem for academics as well as for managers. Corporate debt policy has been studied in the context of both large and small firms in developed countries, but comparatively less developed countries have received much less attention in the literature. This is particularly true in the case of medium income economies with an above average weight of financial intermediaries. This paper tests the factors affecting the capital structure decision of small firms in one such country. The pooled time series cross‐section regression estimates for 995 firms and four years, suggests variables such as taxes, bankruptcy costs, size, collateral, age and growth opportunities affect the capital structure decisions of small firms. These findings have significant implications, both at the firm level and for the support of policies that redefine the financial infrastructure that may foster the emergence of local entrepreneurs in these economies.
Insurance customers’ assessment of service quality: a critical evaluation
Authors: Joseph Mathew , Stone George , Anderson Krista
Published: March 2003

Increased competition from their traditionally, “non‐insurance” partners in the financial services industry has forced “insurance only” companies to enter areas once considered exclusively part of the financial services market. The melding of the insurance, banking, and brokerage industries into one composite financial service industry has created confusion in the minds of many customers who were once able to delineate neatly company product lines. In order to remain competitive in a deregulated industry that has more or less encroached on all financial service providers, insurance companies and their sales representatives have had to reevaluate their traditional methods of attracting and keeping customers. To be successful in this endeavor, agents must take a closer look at just how they treat their customers. Therefore, examines a model proposed as an instrument to assess some of the possible determinants of customer loyalty. The model is based on agents’ ability to deliver on factors related to service quality. The measurement scale used in the study is based on the importance/performance paradigm. The results, somewhat surprisingly, indicate that respondents believe their individual agent is performing at an above average level. Provides conclusions and recommendations.
Towards a taxonomy of entrepreneurial learning experiences among potential entrepreneurs
Authors: Erikson Truls
Published: March 2003

In order to become novice, portfolio or serial entrepreneurs, individuals must first establish themselves as nascent entrepreneurs. Hence, the focus of this article is the factors that lead early stage career individuals to choose business venturing rather than any other career path. In this article, taxonomy of entrepreneurial typologies is developed based on determinants of entrepreneurial competence. By employing Wood and Bandura’s (1998) mastery experience, vicarious experience and social experience, eight tentative typologies emerge.
Noncovalent scFv multimers of tumor‐targeting anti‐Lewisy hu3S193 humanized antibody
Authors: Power Barbara E. , Doughty Larissa , Shapira Deborah R. , Burns John E. , Bayly Ann M. , Caine Joanne M. , Liu Zhanqi , Scott Andrew M. , Hudson Peter J. , Kortt Alexander A.
Published: March 2003

Single‐chain variable fragments (scFvs) of anti‐Lewisy hu3S193 humanized antibody were constructed by joining the VH and VL domains with either +2 residues, +1 residue, or by directly linking the domains. In addition two constructs were synthesized in which one or two C‐terminal residues of the VH domain were removed (−1 residue, −2 residue) and then joined directly to the VL domain. An scFv construct in the reverse orientation with the VL joined directly to the VH domain was also synthesized. Upon transformation into Escherichia coli all scFv constructs expressed active protein. Binding activity, multimeric status, and multivalent properties were assessed by flow cytometry, size exclusion chromatography, and biosensor analysis. The results for hu3S193 scFvs are consistent with the paradigm that scFvs with a linker of +3 residues or more associate to form a non‐covalent dimer, and those with a shorter linker or directly linked associate predominantly to form a non‐covalent trimer and tetramer that are in equilibrium. While the association of V domains to form either a dimer or trimer/tetramer is governed by the length of the linker, the stability of the trimer/tetramer in the equilibrium mixture is dependent on the affinity of the interaction of the individual V domains to associate to form the larger Fv module.
Using nondenaturing mass spectrometry to detect fortuitous ligands in orphan nuclear receptors
Authors: Potier Noelle , Billas Isabelle M.L. , Steinmetz Anke , Schaeffer Christine , van Dorsselaer Alain , Moras Dino , Renaud Jean‐Paul
Published: March 2003

Nondenaturing electrospray mass spectrometry (ESI‐MS) has been used to reveal the presence of potential ligands in the ligand‐binding domain (LBD) of orphan nuclear receptors. This new approach, based on supramolecular mass spectrometry, allowed the detection and identification of fortuitous ligands for the retinoic acid‐related orphan receptor β (RORβ) and the ultraspiracle protein (USP). These fortuitous ligands were specifically captured from the host cell with the proper stoichiometry. After organic extraction, these molecules have been characterized by classic analytical methods and identified as stearic acid for RORβ and a phosphatidylethanolamine (PE) for USP, as confirmed by crystallography. These molecules act as “fillers” and may not be the physiological ligands, but they prove to be essential to stabilize the active conformation of the LBD, enabling its crystallization. The resulting crystal structures provide a detailed picture of the ligand‐binding pocket, allowing the design of highly specific synthetic ligands that can be used to characterize the function of orphan nuclear receptors. An additional advantage of this new method is that it is not based on a functional test and that it can detect low‐affinity ligands.
Denaturation and reassembly of chaperonin GroEL studied by solution X‐ray scattering
Authors: Arai Munehito , Inobe Tomonao , Maki Kosuke , Ikura Teikichi , Kihara Hiroshi , Amemiya Yoshiyuki , Kuwajima Kunihiro
Published: March 2003

We measured the denaturation and reassembly ofEscherichia colichaperonin GroEL using small‐angle solution X‐ray scattering, which is a powerful technique for studying the overall structure and assembly of a protein in solution. The results of the urea‐induced unfolding transition show that GroEL partially dissociates in the presence of more than 2 M urea, cooperatively unfolds at around 3 M urea, and is in a monomeric random coil‐like unfolded structure at more than 3.2 M urea. Attempted refolding of the unfolded GroEL monomer by a simple dilution procedure is not successful, leading to formation of aggregates. However, the presence of ammonium sulfate and MgADP allows the fully unfolded GroEL to refold into a structure with the same hydrodynamic dimension, within experimental error, as that of the native GroEL. Moreover, the X‐ray scattering profiles of the GroEL thus refolded and the native GroEL are coincident with each other, showing that the refolded GroEL has the same structure and the molecular mass as the native GroEL. These results demonstrate that the fully unfolded GroEL monomer can refold and reassemble into the native tetradecameric structure in the presence of ammonium sulfate and MgADP without ATP hydrolysis and preexisting chaperones. Therefore, GroEL can, in principle, fold and assemble into the native structure according to the intrinsic characteristic of its polypeptide chain, although preexisting GroEL would be important when the GroEL folding takes place under in vivo conditions, in order to avoid misfolding and aggregation.
Stable octameric structure of recombinant hemoglobin α2β283 Gly→Cys
Authors: Fablet Christophe , Marden Michael C. , Green Brian N. , Ho Chien , Pagnier Josée , Baudin‐Creuza Véronique
Published: March 2003

We have engineered a recombinant hemoglobin (rHb βG83C) based on the variant Hb Ta‐Li, which oligomerizes through intertetramer disulfide bonds. Size exclusion chromatography and electrospray ionization mass spectrometry show that the rHb βG83C assembles into an oligomeric structure the size of a dimer of tetramers. The oligomer has carbon monoxide‐binding properties similar to those of natural human hemoglobin. Unlike HbA, the oligomer does not participate in dimer exchange. The CO kinetics, auto‐oxidation rate, and gel filtration experiments on the oligomeric βG83C did not show the usual concentration dependence, implying that it does not dissociate easily into smaller species. The octamer could be dissociated by the use of reducing agents. The action of reduced glutathione on oligomeric βG83C exhibited biphasic kinetics for the loss of the octameric form, with a time constant for the rapid phase of about 2 h at 1 mM glutathione. However, the size of oligomer βG83C was not modified after incubation with fresh plasma.
Intermolecular ion pairs maintain the toroidal structure of Pyrococcus furiosus PCNA
Authors: Matsumiya Shigeki , Ishino Sonoko , Ishino Yoshizumi , Morikawa Kosuke
Published: March 2003

Two mutant proliferating cell nuclear antigens from the hyperthermophilic archaeon Pyrococcus furiosus, PfuPCNA(D143A) and PfuPCNA(D143A/D147A), were prepared by site‐specific mutagenesis. The results from gel filtration showed that mutations at D143 and D147 drastically affect the stability of the trimeric structure of PfuPCNA. The PfuPCNA(D143A) still retained the activity to stimulate the DNA polymerase reaction, but PfuPCNA(D143A/D147A) lost the activity. Crystal structures of the mutant PfuPCNAs were determined. Although the wild‐type PCNA forms a toroidal trimer with intermolecular hydrogen bonds between the N‐ and C‐terminal domains, the mutant PfuPCNAs exist as V‐shaped dimers through intermolecular hydrogen bonds between the two C‐terminal domains in the crystal. Because the mutated residues are involved in the intermolecular ion pairs through their side chains in the wild‐type PfuPCNA, these ion pairs seem to play a key role in maintaining the toroidal structure of the PfuPCNA trimer. The comparison of the crystal structures revealed intriguing conformational flexibility of each domain in the PfuPCNA subunit. This structural versatility of PCNA may be involved in the mechanisms for ring opening and closing.
How do helix–helix interactions help determine the folds of membrane proteins? Perspectives from the study of homo‐oligomeric helical bundles
Authors: DeGrado William F. , Gratkowski Holly , Lear James D.
Published: March 2003

The final, structure‐determining step in the folding of membrane proteins involves the coalescence of preformed transmembrane helices to form the native tertiary structure. Here, we review recent studies on small peptide and protein systems that are providing quantitative data on the interactions that drive this process. Gel electrophoresis, analytical ultracentrifugation, and fluorescence resonance energy transfer (FRET) are useful methods for examining the assembly of homo‐oligomeric transmembrane helical proteins. These methods have been used to study the assembly of the M2 proton channel from influenza A virus, glycophorin, phospholamban, and several designed membrane proteins—all of which have a single transmembrane helix that is sufficient for association into a transmembrane helical bundle. These systems are being studied to determine the relative thermodynamic contributions of van der Waals interactions, conformational entropy, and polar interactions in the stabilization of membrane proteins. Although the database of thermodynamic information is not yet large, a few generalities are beginning to emerge concerning the energetic differences between membrane and water‐soluble proteins: the packing of apolar side chains in the interior of helical membrane proteins plays a smaller, but nevertheless significant, role in stabilizing their structure. Polar, hydrogen‐bonded interactions occur less frequently, but, nevertheless, they often provide a strong driving force for folding helix–helix pairs in membrane proteins. These studies are laying the groundwork for the design of sequence motifs that dictate the association of membrane helices.