bluuebunny/crossref_metadata_2025 huggingface dataset:
Market orientation of Nigerian and Kenyan firms: the role of top managers
Authors: Winston Evelyn , Dadzie Kofi Q.
Published: October 2002

In this article, the authors examine the incidence of market orientation of Nigerian and Kenyan firms by focusing on the role of top managers. It is argued that top management’s emphasis on market orientation provides insight into how marginal conditions impact on the applicability of market orientation philosophy in sub‐Saharan African countries. The results suggest that although the level of top management’s emphasis on market orientation is only marginal in these countries, it is likely to increase with the perceived level of competition, the prevalence of a buyer’s market environment and the privatization of the firm. In addition, top managers’ emphasis on market orientation has the strongest influence on the development of market orientation after the presence of international firms and private firms. The results also suggest the importance of understanding the role of top managers in the development of market orientation in Nigeria, Kenya, and other sub‐Saharan African countries.
Integrating advertising theories with conceptual models of services advertising
Authors: Mortimer Kathleen
Published: October 2002

This paper examines two fields of research, services advertising theory and advertising theory. These two areas would seem to be obvious stable‐mates, yet an overview of the literature identifies very little commonality. The paper explores the reasons for this disparity and proposes that the integration of general advertising models into the services advertising literature may provide a useful underpinning for future research. To illustrate this point, the FCB grid is examined in the context of services. The grid provides a practical framework for classification and amalgamates a number of disparate fields of study. It also discloses subject areas which may be fundamental to our understanding of services advertising but have yet to be explored, such as the impact of involvement on advertising strategy and the similarities, which may exist, between certain groups of goods and services.
In search of basic sources that propel organizational learning under recent Taiwanese school reforms
Authors: Jack Lam Y.L. , Peggy Wei H.C. , Wendy Pan H.L. , Marshall Chan C.M.
Published: October 2002

Reports upon research carried out in Taiwan to assess the relative importance of external environment, internal conditions and contextual variables as the major source or momentum for school organizational learning. Maps out the intricate causal relationships among all external, internal and contextual factors with organizational learning process and outcomes. The sample comprised 51 primary and 37 secondary schools. It was found that school internal conditions – notably transformational leadership, positive school culture and supportive structure – outrank factors from other sources as the most critical elements in promoting organizational change, irrespective of the type and nature of schools or individual personal and background factors. Environmental constraints were not shown to be the dominant forces for organizations to engage in learning. Concludes that it is the leaders through their voluntary choice who bring about organizational change.
Environmental disclosures in the annual report
Authors: O’Donovan Gary
Published: October 2002

Much of the extant research into why companies disclose environmental information in the annual report indicates that legitimacy theory is one of the more probable explanations for the increase in environmental disclosures since the early 1980s. Legitimacy theory is based on the idea that in order to continue operating successfully, corporations must act within the bounds of what society identifies as socially acceptable behaviour. The purpose of the practical research undertaken and reported in this paper is to extend the applicability and predictive power of legitimacy theory by investigating to what extent annual report disclosures are interrelated to: attempts to gain, maintain and repair legitimacy; and the choice of specific legitimation tactics. The quasi‐experimental method adopted utilised semi‐structured interviews with senior personnel from three large Australian public companies. The findings indicated support for legitimacy theory as an explanatory factor for environmental disclosures. Moreover, findings about the likelihood of specific micro‐legitimation tactics being used in response to legitimacy threatening environmental issues/events, and dependent on whether the purpose of the response is designed to gain, maintain or repair legitimacy, are reported.
Application of the balanced score‐card concept to develop a conceptual framework to measure facilities management performance within NHS facilities
Authors: Amaratunga Dilanthi , Haigh Richard , Sarshar Marjan , Baldry David
Published: October 2002

This paper discusses the application of the balanced score‐card (BSC) concept as a widely used management framework for optimal measurement of organisational performance within NHS facilities directorates and discusses the fundamental points to cover in its implementation. Thereby, the paper identifies this framework as a strategic measurement and management system for facilities management. BSC formulation within NHS estates and facilities is described as a case study based on a facilities directorate situated in the north west of England, and discussion covers its implementation procedures, evaluation standards and reporting process. The paper further establishes the conceptual framework for performance management for the facilities directorate, as well as consistent techniques useful in undertaking the performance management administration and system oversight functions.
Synchronicity: a post‐structuralist guide to creativity and change
Authors: Durant Rita
Published: October 2002

Synchronicity was coined by Jung in 1955 to refer to the meaningful and acausal, or chance, correlation between an inner and outer event. Insofar as creativity is dependent upon chance for novelty, then creativity and synchronicity may have a supportive relationship. This paper uses narrative to explore the role of paradox in meaning, in chance, and in creativity. The nature of synchronicity, the relationship between synchronicity and creativity, and the implications of this relationship for management are discussed. Such implications include encouraging multiple points of view, understanding the role of emotion in creativity, allowing for movement across metaphorical and physical boundaries, honoring the body, and maintaining a lightness (with humor zand joy) with which to adapt to inevitable “accidents”.
Risk identification – basic stage in risk management
Authors: Tchankova Lubka
Published: October 2002

In this paper risk identification is investigated as a basic stage in risk management. The risk identification phase as the first stage in the risk management process is presented and its leading role for effective risk management is proved. The basic terms that are necessary for building of the frame approach for risk identification are defined: sources of risk‐hazard, factor‐peril‐resources exposed to risk. A classification of risk sources – physical, social, political, operational, economic, legal and cognitive environment – is proposed. It allows covering all types of risk facing the organisation. A grouping of the resources exposed to risk such as physical, human, and financial resources is introduced. It is based on a practical consideration of the risk situations in the organisations.
Linking logistics to strategy in Argentina
Authors: Carranza Octavio , Maltz Arnold , Pablo Antún Juan
Published: October 2002

Qualitative results of a benchmarking process in logistics areas between companies operating in Argentina are presented. A description of the main logistics processes reengineered by these companies is done and some inferences are taken from the study. The companies are finally analyzed according to another benchmarking process generated in Michigan State University, which leads to a discussion on how companies can be characterized as world class in emerging countries.
Consumer performance and quality in services
Authors: Bateson John
Published: October 2002

This article argues for the pivotal role of consumer performance in services – the quality of the ability of the consumer to fulfil their production role. It argues that script theory is ideally suited to understanding performance. It highlights a study which confirms that it is possible to measure the quality of scripts, shows their antecedents and relates script quality directly to performance and consumer satisfaction.
Management accounting and performance measures in Japanese banks
Authors: Hussain Mostaque , Gunasekaran A.
Published: October 2002

Traditional management accounting (MA) has certain limitations, and this highlights the need to examine the nature of cost‐management practices. The implications of non‐financial success factors are emerging in highly competitive financial industries. These receive more emphasis in service organisations that achieve the benefits of performance measurement. Although much is written on the need for accurate performance measures, comparatively little is known about the role of MA in measuring non‐financial performance (NFP). With a view to the implications of MA systems and the measurement of the performance of critical success factors in financial industries, this paper studies the role of MA in NFP in Japanese financial institutions.
Analysis of heat transfer in unlooped and looped pulsating heat pipes
Authors: Shafii M.B. , Faghri A. , Zhang Yuwen
Published: October 2002

An advanced heat transfer model for both unlooped and looped Pulsating Heat Pipes (PHPs) with multiple liquid slugs and vapor plugs has been developed. The thin film evaporation and condensation models have been incorporated with the model to predict the behavior of vapor plugs and liquid slugs in the PHP. The results show that heat transfer in both looped and unlooped PHPs is due mainly to the exchange of sensible heat. Higher surface tension results in a slight increase in the total heat transfer. The diameter, heating wall temperature, and charging ratio have significant effects on the performance of the PHP. Total heat transfer significantly decreased with a decrease in the heating wall temperature. Increasing the diameter of the tube resulted in higher total heat transfer. The results also showed that the PHP could not operate for higher charge ratios.
“Sailing twixt Scylla and Charybdis”: negotiating multiple organisational masculinities
Authors: Boyle Maree V.
Published: October 2002

This qualitative study explores the intersection between organizational masculinity and emotionality within a pre‐hospital emergency services organization. The existence of multiple masculinities within a male‐dominated and emotion‐laden organization indicates that men who work within this context are required to negotiate multiple forms of masculinities within heavily emotionalised organizational regions or spaces. This study found that there were competing tensions between at least two forms of masculinity within the organisation in question. While militarized and managerial/technical forms of masculinity dominate as the principal hegemonic form, a heroic and caring masculinity is also essential to how the organization in question produces its key services. It is argued that forms of masculinity that are closer to the hegemonic ideal type are not “compensatory”, but have to co‐exist with other, albeit more marginalized, masculinities.
Gender differences in ethical decision making
Authors: Glover Saundra H. , Bumpus Minnette A. , Sharp Glynda F. , Munchus George A.
Published: October 2002

Most of the research on fostering ethical climates by making ethical decision choices in organisations has taken place in the last 20 years. Research has moved from specific studies evaluating either individual or situational variables as factors in ethical decision behaviour to more complex models that encompass the interaction of individual and situational factors. This study revisits the influence of the individual variable of gender on ethical decision making. Using a laboratory format and decision exercises that attempted to create realistic business conflict situations through decision scenarios, the influence of demographic factors, specifically gender, and the moral intensity of the conflict situation on ethical decision making are examined in the light of workplace values.
Benchmarking academic standards
Authors: Laugharne Mike
Published: October 2002

This article sets the QAA’s approach to benchmarking academic standards within the wider quality assurance context and considers the ways in which subject benchmarking can be interpreted and used for development and enhancement. The key challenge is for strategic collaboration between all the national agencies and HE institutions that have a legitimate stake in the latter in order to maximise the opportunity for achieving it.
An institutional perspective on QAA subject benchmarking
Authors: Hargreaves Janet , Christou Alexa
Published: October 2002

This paper provides an institutional perspective on the ways in which subject benchmark statements are being and might be used in internal quality assurance processes. The use and value of the benchmarks has to be considered in the light of the changes in the external review process. Institutions appear to be avoiding a culture of rigid compliance, but benchmarks have only been applied in limited ways to date. The potential benefits of subject benchmark statements will only be realised if we can create the conditions within HE institutions and between national bodies that encourage subject communities to use the benchmarking statements developmentally rather than a checklist for accountability.
A model for designing action learning and action research programs
Authors: Zuber‐Skerritt Ortrun
Published: October 2002

Models can be helpful for understanding the essence and/or processes of complex phenomena in a field, because they are simple representations of concept patterns and relationships. This paper presents a generic model for designing action learning programs, including action research projects, within organizations. Core values for action learning programs and explanations for success and potential pitfalls are also discussed. The model has been tested and found useful by many senior managers, academics, postgraduates and consultants in several countries. Readers are encouraged to explore the model in order to apply, refine, adapt it, or to create their own model representing their theoretical framework, concepts, values and systems thinking.
Commercial Internet adoption in China: comparing the experience of small, medium and large businesses
Authors: Riquelme Hernan
Published: October 2002

Earlier research studies predicted that it would be small and medium‐sized businesses that were more likely to adopt and benefit from the use of the Internet because of their greater flexibility. Anecdotal evidence appears in the literature to support this claim; however, little systematic empirical research has been done among SMEs to test this speculation. A sample of 248 companies in Shanghai, China, was divided into small, medium and large groups. The statistical analysis indicates that there are significant differences between large and small companies. Large companies have benefited considerably more from the Internet than small companies not only in their increased sales (derived from the Internet) but also from cost savings. Although the whole sample confirms the main reason for establishing an Internet connection, to gain a competitive advantage, companies also think that the Internet does not work equally for all players.
Diagnosis and reduction of bullwhip in supply chains
Authors: McCullen Peter , Towill Denis
Published: October 2002

“Bullwhip” describes the general tendency for small changes in end‐customer demand to be amplified within a production‐distribution system. A 10 per cent increase in sales to end‐customers can precipitate a 40 per cent upswing in production and subsequent downswing (as excess stocks are depleted) within a three‐echelon supply chain. It is shown how proven material flow control principles significantly reduce bullwhip in a global supply chain. The evidence demonstrates that a methodology, which has evolved over several decades, provides a suitable framework for effective change. Bullwhip is not a new problem; it is a new name coined to describe a very well‐known problem. Some observed barriers to change are briefly reviewed.
Implementing KM – a balanced score card approach
Authors: Arora Ravi
Published: October 2002

In today’s fast changing and non‐linear business environment the only way to gain competitive advantage is by managing intellectual capital, which is more commonly known as knowledge management (KM). There are basically three broad objectives of KM: leveraging the organisation’s knowledge; creating new knowledge or promoting innovation; and increasing collaboration and hence enhancing the skill level of employees. The most common KM programme involves development of a knowledge repository, and forming and nurturing of the communities of practice. These two, jointly, address all the three objectives of KM. Many organisations are embracing KM but few of them are able to implement it successfully to see the benefits. Implementation of KM is a strategic process and needs careful target setting and review. Organisations, which use balanced scorecard for strategy deployment, can effectively implement KM in their organisation by developing and deploying a KM index.
Communication and loyalty among knowledge workers: a resource of the firm theory view
Authors: Smith Alan D. , Rupp William T.
Published: October 2002

The traditional methods of managing human capital, creativity, innovation, and the learning culture within an organization have long over‐shadowed the management of the professional intellect. As with the resource based view (RVB) of the firm, the intangible strategic intelligence creates most of the professional intellect of an organization, and operates on the following four levels (in increasing importance): cognitive knowledge or basic mastery of a professional discipline; advanced skills or the ability to translate theory into effective execution or practice; systems understanding or the deep knowledge of the cause and effect relationships underlying the professional discipline; and self‐motivated creativity or the motivation and adaptability for success. The interaction of these factors, along with enhanced communications, allow nurturing organizations the ability to thrive in the face of today’s rapid changes and renew their cognitive knowledge, especially where it increases the loyalty of knowledge workers.
Implementation of success factors in new product development – the missing links?
Authors: Jensen Bjarne , Harmsen Hanne
Published: October 2002

This paper addresses companies’ lack of implementation of success factors in new product development. Drawing on theory in the competence perspective and an exploratory empirical study, the paper points to two major areas that have not been covered by previous studies on new product development success factors. The two areas are knowledge and skills of individual employees, values and norms and it is suggested that increased understanding of these two areas holds potential in making identified success factors more accessible to companies.
Institutional assessment tools for sustainability in higher education
Authors: Shriberg Michael
Published: October 2002

This paper analyzes recent efforts to measure sustainability in higher education across institutions. The benefits of cross‐institutional assessments include: identifying and benchmarking leaders and best practices; communicating common goals, experiences, and methods; and providing a directional tool to measure progress toward the concept of a “sustainable campus”. Ideal assessment tools identify the most important attributes of a sustainable campus, are calculable and comparable, measure more than eco‐efficiency, assess processes and motivations and are comprehensible to multiple stakeholders. The 11 cross‐institutional assessment tools reviewed in this paper vary in terms of stage of development and closeness to the “ideal tool”. These tools reveal (through their structure and content) the following critical parameters to achieving sustainability in higher education: decreasing throughput; pursuing incremental and systemic change simultaneously; including sustainability education as a central part of curricula; and engaging in cross‐functional and cross‐institutional efforts.
Sustainable development in higher education in the Philippines
Authors: Segovia Victoria M. , Galang Angelina P.
Published: October 2002

The Philippines is one of the signatories to the historic Agenda 21 and was noted to be among the first countries to establish a National Council for Sustainable Development. Ten years after Rio, global society is again confronted with the question of whether sustainable development as a concept, philosophy and practice has improved the lives of peoples in different countries and cultures. This article attempts to discuss initiatives through which tertiary education has helped bring about sustainable development in the Philippines. It posits that for sustainable development to happen it must take root in the consciousness and cultures of society, a task in which education plays a very important part. The article discusses the efforts of two national networks for environmental education, the Environmental Education Network of the Philippines, Inc. (EENP) and the Philippine Association of Tertiary Level Educational Institutions in Environmental Protection and Management (PATLEPAM), which advocate for the integration of sustainable development in school curricula as well as in campus administration and organizational culture. It also includes the pioneering efforts of one institution, Miriam College, to integrate environmental education in its programs as part of its mission and commitment to become a genuine “steward of creation”.
CEOs and development of the meaningful mission statement
Authors: Analoui Farhad , Karami Azhdar
Published: October 2002

Developing a mission statement has been considered a crucial factor in the formulation of business strategy in organisations. The mission statement promotes a sense of shared expectations in employees and, not surprisingly, it has recently been regarded as increasingly important in small‐ and medium‐sized enterprises (SMEs) in the electronic industry. One major reasons for this is the growing complexity and dynamic competitive environments in which these enterprises have operated and managed to find themselves. Mission statements have become a management tool most commonly used by chief executive officers (CEOs) over the last decade. One exercise that both academics and practitioners have deemed strategically critical to the success of an enterprise is the development of a meaningful mission statement. This article explores the perceptions of CEOs of their mission statement in SMEs. It is based on the findings of recent research in 508 firms in the electrical and electronic industry in the UK. The study, amongst other things, investigated the existence and content of the mission statements and, accordingly, it determines the relationships (if any) between a SME’s development of a meaningful mission statement and selected performance outcomes of the firm.
Design of an optimal Chebyshev‐expanded discrimination function for globular proteins
Authors: Fain Boris , Xia Yu , Levitt Michael
Published: October 2002

We describe the construction of a scoring function designed to model the free energy of protein folding. An optimization technique is used to determine the best functional forms of the hydrophobic, residue‐residue and hydrogen‐bonding components of the potential. The scoring function is expanded by use of Chebyshev polynomials, the coefficients of which are determined by minimizing the score, in units of standard deviation, of native structures in the ensembles of alternate decoy conformations. The derived effective potential is then tested on decoy sets used conventionally in such studies. Using our scoring function, we achieve a high level of discrimination between correct and incorrect folds. In addition, our method is able to represent functions of arbitrary shape with fewer parameters than the usual histogram potentials of similar resolution. Finally, our representation can be combined easily with many optimization methods, because the total energy is a linear function of the parameters. Our results show that the techniques of Z‐score optimization and Chebyshev expansion work well.
Thermal denaturation of Bungarus fasciatus acetylcholinesterase: Is aggregation a driving force in protein unfolding?
Authors: Shin I. , Wachtel E. , Roth E. , Bon C. , Silman I. , Weiner L.
Published: October 2002

A monomeric form of acetylcholinesterase from the venom of Bungarus fasciatus is converted to a partially unfolded molten globule species by thermal inactivation, and subsequently aggregates rapidly. To separate the kinetics of unfolding from those of aggregation, single molecules of the monomeric enzyme were encapsulated in reverse micelles of Brij 30 in 2,2,4‐trimethylpentane, or in large unilamellar vesicles of egg lecithin/cholesterol at various protein/micelle (vesicle) ratios. The first‐order rate constant for thermal inactivation at 45°C, of single molecules entrapped within the reverse micelles (0.031 min−1), was higher than in aqueous solution (0.007 min−1) or in the presence of normal micelles (0.020 min−1). This clearly shows that aggregation does not provide the driving force for thermal inactivation of BfAChE. Within the large unilamellar vesicles, at average protein/vesicle ratios of 1:1 and 10:1, the first‐order rate constants for thermal inactivation of the encapsulated monomeric acetylcholinesterase, at 53°C, were 0.317 and 0.342 min−1, respectively. A crosslinking technique, utilizing the photosensitive probe, hypericin, showed that thermal denaturation produces a distribution of species ranging from dimers through to large aggregates. Consequently, at a protein/vesicle ratio of 10:1, aggregation can occur upon thermal denaturation. Thus, these experiments also demonstrate that aggregation does not drive the thermal unfolding of Bungarus fasciatus acetylcholinesterase. Our experimental approach also permitted monitoring of recovery of enzymic activity after thermal denaturation in the absence of a competing aggregation process. Whereas no detectable recovery of enzymic activity could be observed in aqueous solution, up to 23% activity could be obtained for enzyme sequestered in the reverse micelles.
Active site geometry of oxalate decarboxylase from Flammulina velutipes: Role of histidine‐coordinated manganese in substrate recognition
Authors: Chakraborty Subhra , Chakraborty Niranjan , Jain Deepti , Salunke Dinakar M. , Datta Asis
Published: October 2002

Oxalate decarboxylase (OXDC) from the wood‐rotting fungus Flammulina velutipes, which catalyzes the conversion of oxalate to formic acid and CO2 in a single‐step reaction, is a duplicated double‐domain germin family enzyme. It has agricultural as well as therapeutic importance. We reported earlier the purification and molecular cloning of OXDC. Knowledge‐based modeling of the enzyme reveals a β‐barrel core in each of the two domains organized in the hexameric state. A cluster of three histidines suitably juxtaposed to coordinate a divalent metal ion exists in both the domains. Involvement of the two histidine clusters in the catalytic mechanism of the enzyme, possibly through coordination of a metal cofactor, has been hypothesized because all histidine knockout mutants showed total loss of decarboxylase activity. The atomic absorption spectroscopy analysis showed that OXDC contains Mn2+ at up to 2.5 atoms per subunit. Docking of the oxalate in the active site indicates a similar electrostatic environment around the substrate‐binding site in the two domains. We suggest that the histidine coordinated manganese is critical for substrate recognition and is directly involved in the catalysis of the enzyme.
α1‐Proteinase inhibitor mutants with specificity for plasma kallikrein and C1s but not C1
Authors: Sulikowski Thomas , Bauer Bryan A. , Patston Philip A.
Published: October 2002

Coagulation and complement proteinases are activated in sepsis, and one approach to therapy is to develop proteinase inhibitors that will specifically inhibit these proteinases without inhibiting activated protein C, a proteinase that is beneficial to survival. In this study, we made mutants of the serpin α1‐PI, designed to mimic the specificity of C1‐inhibitor. The P3‐P2‐P1 residues of α1‐PI were changed from IPM to LGR and PFR, sequences preferred by C1s and kallikrein, respectively. Inhibition of C1s, kallikrein, factor XIIa, and activated protein C was assessed by SDS‐PAGE, and by determination of the kapp and SI. α1‐PI‐LGR inhibited C1s with a rate of 7790 M−1s−1, but only minimal inhibition of C1 in a hemolytic assay was observed. Kallikrein, factor XIIa, and activated protein C were inhibited with rates of 382,180 M−1s−1, 10,400 M−1s−1, and 3500 M−1s−1, respectively. α1‐PI‐PFR was a poor inhibitor of C1s, factor XIIa, and activated protein C, but had enhanced reactivity with kallikrein. Changing the P4′ residue of α1‐PI‐LGR Pro to Glu reduced the activity with C1s, consistent with the idea that C1s requires hydrophobic residues in this region of the serpin for optimal interaction. The data provide insight into the requirements for kallikrein and C1s inhibition necessary for designing inhibitors with appropriate properties for further investigation as therapeutic agents.
Surface adhesion of fusion proteins containing the hydrophobins HFBI and HFBII from Trichoderma reesei
Authors: Linder Markus , Szilvay Geza R. , Nakari‐Setälä Tiina , Söderlund Hans , Penttilä Merja
Published: October 2002

Hydrophobins are surface‐active proteins produced by filamentous fungi, where they seem to be ubiquitous. They have a variety of roles in fungal physiology related to surface phenomena, such as adhesion, formation of surface layers, and lowering of surface tension. Hydrophobins can be divided into two classes based on the hydropathy profile of their primary sequence. We have studied the adhesion behavior of two Trichoderma reesei class II hydrophobins, HFBI and HFBII, as isolated proteins and as fusion proteins. Both hydrophobins were produced as C‐terminal fusions to the core of the hydrolytic enzyme endoglucanase I from the same organism. It was shown that as a fusion partner, HFBI causes the fusion protein to efficiently immobilize to hydrophobic surfaces, such as silanized glass and Teflon. The properties of the surface‐bound protein were analyzed by the enzymatic activity of the endoglucanase domain, by surface plasmon resonance (Biacore), and by a quartz crystal microbalance. We found that the HFBI fusion forms a tightly bound, rigid surface layer on a hydrophobic support. The HFBI domain also causes the fusion protein to polymerize in solution, possibly to a decamer. Although isolated HFBII binds efficiently to surfaces, it does not cause immobilization as a fusion partner, nor does it cause polymerization of the fusion protein in solution. The findings give new information on how hydrophobins function and how they can be used to immobilize fusion proteins.
Impact of domain interchange on conformational stability and equilibrium folding of chimeric class μ glutathione transferases
Authors: Luo Jiann‐Kae , Hornby Judith A.T. , Wallace Louise A. , Chen Jihong , Armstrong Richard N. , Dirr Heini W.
Published: October 2002

Rat μ class glutathione transferases M1‐1 and M2‐2 are homodimers that share a 78% sequence identity but display differences in stability. M1‐1 is more stable at the secondary and tertiary structural levels, whereas its quaternary structure is less stable. Each subunit in these proteins consists of two structurally distinct domains with intersubunit contacts occurring between domain 1 of one subunit and domain 2 of the other subunit. The chimeric subunit variants M(12), which has domain 1 of M1 and domain 2 of M2, and its complement M(21), were used to investigate the conformational stability of the chimeric homodimers M(12)‐(12) and M(21)‐(21) to determine the contribution of each domain toward stability. Exchanging entire domains between class μ GSTs is accommodated by the GST fold. Urea‐induced equilibrium unfolding data indicate that whereas the class μ equilibrium unfolding mechanism (i.e., N2 ↔ 2I ↔ 2U) is not altered, domain exchanges impact significantly on the conformational stability of the native dimers and monomeric folding intermediates. Data for the wild‐type and chimeric proteins indicate that the order of stability for the native dimer (N2) is M2‐2 > M(12)‐(12) M1‐1 ∼ M(21)‐(21), and that the order of stability of the monomeric intermediate (I) is M1 > M2 ∼ M(12) > M(21). Interactions involving Arg 77, which is topologically conserved in GSTs, appear to play an important role in the stability of both the native dimeric and folding monomeric structures.
The role of irregular unit, GAAS, on the secondary structure of Bombyx mori silk fibroin studied with 13C CP/MAS NMR and wide‐angle X‐ray scattering
Authors: Asakura Tetsuo , Sugino Rena , Okumura Tatsushi , Nakazawa Yasumoto
Published: October 2002

Bombyx mori silk fibroin is a fibrous protein whose fiber is extremely strong and tough, although it is produced by the silkworm at room temperature and from an aqueous solution. The primary structure is mainly Ala‐Gly alternative copolypeptide, but Gly‐Ala‐Ala‐Ser units appear frequently and periodically. Thus, this study aims at elucidating the role of such Gly‐Ala‐Ala‐Ser units on the secondary structure. The sequential model peptides containing Gly‐Ala‐Ala‐Ser units selected from the primary structure of B. mori silk fibroin were synthesized, and their secondary structure was studied with 13C CP/MAS NMR and wide‐angle X‐ray scattering. The 13C isotope labeling of the peptides and the 13C conformation‐dependent chemical shifts were used for the purpose. The Ala‐Ala units take antiparallel β‐sheet structure locally, and the introduction of one Ala‐Ala unit in (Ala‐Gly)15 chain promotes dramatical structural changes from silk I (repeated β‐turn type II structure) to silk II (antiparallel β‐sheet structure). Thus, the presence of Ala‐Ala units in B. mori silk fibroin chain will be one of the inducing factors of the structural transition for silk fiber formation. The role of Tyr residue in the peptide chain was also studied and clarified to induce “locally nonordered structure.”
The β‐barrel finder (BBF) program, allowing identification of outer membrane β‐barrel proteins encoded within prokaryotic genomes
Authors: Zhai Yufeng , Saier Milton H.
Published: October 2002

Many outer membrane proteins (OMPs) in Gram‐negative bacteria possess known β‐barrel three‐dimensional (3D) structures. These proteins, including channel‐forming transmembrane porins, are diverse in sequence but exhibit common structural features. We here report computational analyses of six outer membrane proteins of known 3D structures with respect to (1) secondary structure, (2) hydropathy, and (3) amphipathicity. Using these characteristics, as well as the presence of an N‐terminal targeting sequence, a program was developed allowing prediction of integral membrane β‐barrel proteins encoded within any completely sequenced prokaryotic genome. This program, termed the β‐barrel finder (BBF) program, was used to analyze the proteins encoded within the Escherichia coli genome. Out of 4290 sequences examined, 118 (2.8%) were retrieved. Of these, almost all known outer membrane proteins with established β‐barrel structures as well as many probable outer membrane proteins were identified. This program should be useful for predicting the occurrence of outer membrane proteins in bacteria with completely sequenced genomes.
Interdomain engineered disulfide bond permitting elucidation of mechanisms of inactivation of coagulation factor Va by activated protein C
Authors: Gale Andrew J. , Xu Xiao , Pellequer Jean‐Luc , Getzoff Elizabeth D. , Griffin John H.
Published: October 2002

Procoagulant factor Va (FVa) is inactivated via limited proteolysis at three Arg residues in the A2 domain by the anticoagulant serine protease, activated protein C (APC). Cleavage by APC at Arg306 in FVa causes dissociation of the A2 domain from the heterotrimeric A1:A2:A3 structure and complete loss of procoagulant activity. To help distinguish inactivation mechanisms involving A2 domain dissociation from inactivation mechanisms involving unfavorable changes in factor Xa (FXa) affinity, we used our FVa homology model to engineer recombinant FVa mutants containing an interdomain disulfide bond (Cys609‐Cys1691) between the A2 and A3 domains (A2‐SS‐A3 mutants) in addition to cleavage site mutations, Arg506Gln and Arg679Gln. SDS‐PAGE analysis showed that the disulfide bond in A2‐SS‐A3 mutants prevented dissociation of the A2 domain. In the absence of A2 domain dissociation from the A1:A2:A3 trimer, APC cleavage at Arg306 alone caused a sevenfold decrease in affinity for FXa, whereas APC cleavages at Arg306, Arg506, and Arg679 caused a 70‐fold decrease in affinity for FXa and a 10‐fold decrease in the kcat of the prothrombinase complex for prothrombin without any effect on the apparent Km for prothrombin. Therefore, for FVa inactivation by APC, dissociation of the A2 domain may provide only a modest final step, whereas the critical events are the cleavages at Arg506 and Arg306, which effectively inactivate FVa before A2 dissociation can take place. Nonetheless, for FVa Leiden (Gln506‐FVa) inactivation by APC, A2 domain dissociation may become mechanistically important, depending on the ambient FXa concentration.
Systems of Inequalities and Numerical Semigroups
Authors: Rosales J. C. , García-Sánchez P. A. , García-García J. I. , Branco M. B.
Published: October 2002

A one‐to‐one correspondence is described between the set S(m) of numerical semigroups with multiplicity m and the set of non‐negative integer solutions of a system of linear Diophantine inequalities. This correspondence infers in S(m) a semigroup structure and the resulting semigroup is isomorphic to a subsemigroup of Nm−1. Finally, this result is particularized to the symmetric case.
Majorations Uniformes de Normes D'Inverses Dans Les Algèbres de Beurling
Authors: El-Fallah O. , Ezzaaraoui A.
Published: October 2002

The Beurling algebras l1(D,ω)(D=N,Z) that are semi‐simple, with compact Gelfand transform, are considered. The paper gives a necessary and sufficient condition (on ω) such that l1(D,ω) possesses a uniform quantitative version of Wiener's theorem in the sense that there exists a function ϕ:]0,+∞[→]0,+∞ such that, for every invertible element x in the unit ball of l1(D,ω), we have

‖x−1‖⩽ϕ(r(x−1)) r(x−1) is the spectral radius of x−1.
Tangential Lusternik–Schnirelmann Category of Foliations
Authors: Colman Hellen , Macias-Virgós Enrique
Published: October 2002

A new invariant of (integrable) homotopy type for foliations is introduced: the tangential category of a foliated manifold.

The classical Lusternik–Schnirelmann theory is generalized to foliations and the relations of the tangential category with other known invariants such as the fibrewise and the equivariant category are studied. Cohomological lower bounds are provided in terms of foliated cohomology.

If the foliation is a product, the tangential category coincides with the ordinary category of the leaves. In general it is just bounded below. Estimates are given of the tangential category for compact‐Hausdorff foliations and suspensions. Examples show that the lower and upper bounds are realized.
The Spectral Set Conjecture and Multiplicative Properties of Roots of Polynomials
Authors: Łaba I.
Published: October 2002

Fuglede's conjecture states that a set Ω⊂Rn tiles R by translations if and only if L2(Ω) has an orthogonal basis of exponentials. New partial results are obtained supporting the conjecture in dimension 1.
The release and vascular action of bradykinin in the isolated perfused bovine udder
Authors: Zeitlin I. J. , Eshraghi H. R.
Published: October 2002

It has been postulated that the mammary kinin system may play a role in modulating mammary blood flow. Until the present study, the local release of bradykinin (BK) or other kinin system constituents into the mammary vasculature had not been reported and there were also conflicting findings on the action of BK on udder vasculature. Udders were removed from healthy lactating cows at slaughter. Pairs of ipsilateral quarters were perfused with Tyrode solution through the external pudendalis artery and drained via the cranial superficial epigastric vein. Mammary secretion was collected through teat cannulae. The perfusion pressure was linearly related to perfusate flux between 60 and 210 ml min−1 and the flow rate was adjusted (110‐150 ml min−1) to give a basal pressure of 85 mmHg. PO2, PCO2 and pH in the venous effluent perfusate stabilised at 157 ± 10 mmHg, 50.1 ± 2.4 mmHg and 7.1 ± 0.03, respectively. The venous effluent contained immunoreactive BK and BK precursor, tissue kallikrein activity, and bradykinin‐destroying enzyme. The concentration of BK stabilised at 378 ± 48 pg (ml perfusate)−1, that of trypsin‐activated BK precursor was 679 ± 59 pg BK equivalents ml−1 and that of tissue kallikrein, measured as cleavage of D‐Val.Leu.Arg‐p‐nitroanilide (D‐Val.Leu.Arg‐pNA), was 5.5 ± 1.7 nmol p‐NA h−1 ml−1. Arterial infusion of phenylephrine (0.49‐490 μM) produced increases in perfusion pressure (vasoconstriction). Acetylcholine (ACh) (0.55‐55 μM) and BK (0.1‐10 μM) produced only vasodilatation. BK (EC50= 1.00±0.04 μM) was a more potent vasodilator than ACh (EC50= 9.57±0.49 μM). The basal BK concentration was 250 times below the threshold for vasoactivity. The udder produced a milk‐like secretion, which was dependent on perfusate flow and contained a concentration of BK which remained unchanged from 60 to 180 min of perfusion (231 ± 31 pg ml−1) unlike that in the venous effluent which doubled between 60 and 120 min. Thus, in addition to its secretion into milk, BK, together with its precursor and tissue kallikrein, is continuously released into the vasculature of the isolated, perfused, lactating bovine udder.
Short‐term cardiovascular oscillations in man: measuring and modelling the physiologies
Authors: Cohen Michael A. , Taylor J. Andrew
Published: October 2002

Research into cardiovascular variabilities intersects both human physiology and quantitative modelling. This is because respiratory and Mayer wave (or 10 s) cardiovascular oscillations represent the integrated control of a system through both autonomic branches by systemic haemodynamic changes within a fluid‐filled, physical system. However, our current precise measurement of short‐term cardiovascular fluctuations does not necessarily mean we have an adequate understanding of them. Empirical observation suggests that both respiratory and Mayer wave fluctuations derive from mutable autonomic and haemodynamic inputs. Evidence strongly suggests that respiratory sinus arrhythmia both contributes to and buffers respiratory arterial pressure fluctuations. Moreover, even though virtual abolition of all R‐R interval variability by cholinergic blockade suggests that parasympathetic stimulation is essential for expression of these variabilities, respiratory sinus arrhythmia does not always reflect a purely vagal phenomenon. The arterial baroreflex has been cited as the mechanism for both respiratory and Mayer wave frequency fluctuations. However, data suggest that both cardiac vagal and vascular sympathetic fluctuations at these frequencies are independent of baroreflex mechanisms and, in fact, contribute to pressure fluctuations. Results from cardiovascular modelling can suggest possible sources for these rhythms. For example, modelling originally suggested low frequency cardiovascular rhythms derived from intrinsic delays in baroreceptor control, and experimental evidence subsequently corroborated this possibility. However, the complex stochastic relations between and variabilities in these rhythms indicate no single mechanism is responsible. If future study of cardiovascular variabilities is to move beyond qualitative suggestions of determinants to quantitative elucidation of critical physical mechanisms, both experimental design and model construction will have to be more trenchant.
Properties of spontaneously active cells distributed in the submucosal layer of mouse proximal colon
Authors: Yoneda Satoshi , Takano Hiromichi , Takaki Miyako , Suzuki Hikaru
Published: October 2002

Intracellular electrical activity was recorded from smooth muscle tissues of the mouse proximal colon, and the impaled cells were visualized by injection of neurobiotin. Slow potentials with initial fast and subsequent plateau components (plateau potentials), generated at a frequency of 14.8 min−1, were recorded from oval‐shaped cells with bipolar processes. Periodic bursts of spike potentials (4.6 min−1) and bursts of oscillatory potentials (4.3 min−1) were recorded in circular and longitudinal smooth muscle cells, respectively. Nifedipine (0.1 μm) abolished the bursts of spike and oscillatory potentials and reduced the duration of plateau potentials. The plateau potentials were abolished by 1 μm nifedipine. The plateau potentials were also abolished by cyclopiazonic acid (an inhibitor of Ca2+ uptake into internal stores) or 2‐aminoethoxydiphenyl borate (an inhibitor of inositol 1,4,5‐trisphosphate receptor‐mediated Ca2+ release), and were inhibited by bis‐(aminophenoxy) ethane‐N,N,N′,N′‐tetraacetic acid acetoxymethyl ester (a chelator of intracellular Ca2+). Carbonyl cyanide m‐chlorophenylhydrazone (a mitochondrial protonophore) abolished plateau potentials, and its action was not mimicked by oligomycin (an inhibitor of mitochondrial ATPase). It is concluded that in mouse proximal colon, submucosal c‐kit‐positive bipolar cells spontaneously generate plateau potentials with rhythms different from those generated by smooth muscle cells. The plateau potentials are generated through activation of voltage‐gated Ca2+ channels, which are coupled to the release of Ca2+ from the internal stores and the handling of Ca2+ in mitochondria.
Application of physiological genomics to the study of hearing disorders
Authors: Heller Stefan
Published: October 2002

Although the biophysical principles of how the ear operates are reasonably well understood, little is known about the specific genes that confer normal function to the inner ear. Nevertheless, the recent implementation of genomic tools has led to extraordinary progress in the identification of mutated genes that cause non‐syndromic and syndromic forms of deafness. Part of this success is directly related to the sequencing of the human and mouse genomes and improved gene annotation methods. This review discusses how physiological genomic tools, such as genomic databases, expressed sequence tag databases and DNA arrays have been applied to find candidate genes for important molecular processes in the inner ear. It also illustrates, using the discovery of genes encoding essential components of cochlear K+ homeostasis as an example, how the combination of physiological genomic tools with physiological and morphological information has led to an in‐depth understanding of cochlear ion homeostasis. Finally, it discusses how the use of applied genomic tools, such as gene arrays, will further advance our knowledge of how the inner ear works, develops, ages and regenerates.