bluuebunny/crossref_metadata_2025 huggingface dataset:
The trainee system in professional football in England and Wales
Authors: Stewart Gerry , Sutherland John
Published: July 2002

The Youth Training Scheme (YTS) became operational nationally in September 1983. In May 1990, Youth Training (YT) was introduced to replace YTS. Throughout the economy, substantial numbers of new entrants to the labour market were subsidized by both schemes. In professional football in England and Wales, the former ad hoc system of “apprenticeship” was replaced by a more uniform systemic programme of both “specific” and “general” training, operating under the aegis of the Footballers’ Further Education and Vocational Training Society. Examines data to show how, subsequent to the implementation of the YTS/YT schemes in professional football, the number of registered contract professionals has increased: the ratio of contract professionals to trainees has decreased and the inter‐divisional distribution of apprentices/trainees has changed, with proportionately more trainees than before now registered with clubs in the lower divisions. Additionally, describes the “specific” (i.e. football club‐based) and “general” (i.e. college‐based) components of the training programme.
Predicting immediate and longer‐term transfer of training
Authors: Axtell Carolyn M. , Maitlis Sally , Yearta Shawn K.
Published: July 2002

Describes an exploratory investigation conducted to examine factors affecting the initial and sustained transfer of interpersonal skills training to the workplace. Demonstrates the ongoing role of trainee motivation in the immediate and longer term transfer of learned skills to work. Suggests that initial transfer of skills is an important prerequisite of subsequent skill application in the workplace. Concludes that factors which promote initial transfer of training, such as the perceived relevance/usefulness of the course, appear to have an indirect effect on later use of trained skills. Also concludes that, in the long term, individuals with more autonomy in their jobs are more likely to apply learned skills, perhaps because they are more able to create opportunities for using trained skills at work. This may be especially true for those with high levels of motivation. Discusses the implications of these findings both for individuals learning new skills, and for organizations optimizing the utility of their training provision.
Evaluating quality and reputation of human resource management
Authors: Baruch Yehuda
Published: July 2002

Reports that the evaluation of organizational units is of great importance for the organization. However, we face severe difficulties when conducting such processes, especially with regard to the human resource management (HRM) department. Discusses conventional approaches to such evaluation, focuses on their limitations, and suggests a new method for such an evaluation. The suggested method is based on an additive measure comprising HRM practices carried out in the organization. It was applied in an empirical study in which the HRM quality of 51 organizations was evaluated by four different sources: the organization’s top management, the organization’s employees, the environment (assessment of reputation), and an objective measure that was established based on the suggested approach. Concludes that, among the set of intercorrelations between the sources, the last one had the highest correlation with the others, which may indicate the value of the suggested method.
Robots for automating construction – an abundance of research
Authors: Kochan Anna
Published: July 2002

Reviews the 16th International Symposium on Automation and Robotics in Construction held in Madrid, Spain, in September 1999; outlines robotic projects relating to construction activities.
Flexible virtual tools for programming robotic finishing operations
Authors: Kesavadas T. , Subramanium Hari
Published: July 2002

In this paper a Virtual Reality (VR) based interactive system for specifying robotic tasks using virtual tools is described. This environment allows an operator to reach into a live video scene and direct robots to use corresponding real tools in complex scenarios that involve integrating a variety of otherwise autonomous technologies. The attribute‐rich virtual tool concept provides a human‐machine interface that is robust to unanticipated developments and tunable to the specific requirements of a particular task. This interactive specification concept is applied to intermediate manufacturing processes such as robotic based grinding and polishing. Further, in this research, when the operator selects a virtual tool by “clicking” on an icon of the desired tool in a virtual toolbox, a representation of the real‐world tool, laden with associated attributes is displayed. A new flavor of tool is created from the parent class when desired. According to operating constraints, new subclasses, which are offspring of the parent tool class, are derived. A specific instance of a tool can be evoked from any of the derived subclasses. Such attribute laden virtual tools enable easy control of otherwise complicated manufacturing task planning. This paper also explores the use of JAVA applet based interface for using these tools over the Internet. Successful implementation of such a Web‐based system will open the door to the use of robots in many other human intensive manufacturing processes.
Overall equipment effectiveness as a measure of operational improvement – A practical analysis
Authors: Dal Bulent , Tugwell Phil , Greatbanks Richard
Published: July 2002

Presents a practical analysis of operational performance measurement at Airbags International Ltd (AIL), a supplier of airbag safety devices to the automotive industry. First, the primary measure of overall equipment effectiveness (OEE) is described. Its implementation and use within the operational environment of AIL is then described and analysed. Finally, presents the potential benefits of developing OEE as an operational measure and contrasts AIL’s performance with other applications of OEE found with the research literature.
The dynamics of the corporate education market and the role of business schools
Authors: Prince Christopher , Stewart Jim
Published: July 2002

Highlights the rapidly growing market for corporate management education, and the emerging role business schools are playing in this market. The article draws on 30 interviews conducted with both HR managers and academics from both new and traditional universities. The first part of the article, drawing on a number of case studies, highlights a number of emerging trends, while the second part of the article examines business school responses. The article closes by highlighting a number of implications for both business schools and organisations seeking company specific management education programmes.
Predictive validity of TAT and CMPS on the entrepreneurial activity, “start of a new business”: a longitudinal study
Authors: Hansemark Ove C.
Published: July 2002

Self‐reporting questionnaires as well as projective tests are frequently used in entrepreneurship and management research that is concerned with the need for achievement. The purpose of this study was to examine whether an objective test such as the Cesarec‐Markes Personal Scheme (CMPS) and the Thematic Apperception Test (TAT) have any predictive validity on the entrepreneurial activity of starting a new business. The study had a longitudinal design. Psychological measurement of need for achievement was conducted before the entrepreneurial decision was made. The period between the psychological measurement and the collection of the data for the longitudinal study was 11 years. In summary, the result of the study does not support the hypothesis that the TAT has any predictive validity. On the other hand, the result of the study does support the hypothesis that the objective test CMPS has predictive validity.
Direct finite element solution for the capacitance, conductance or inductance, and force in linear electrostatic and magnetostatic problems
Authors: Spink D.M.
Published: July 2002

Presents a direct solution method for the determination of quantities such as capacitance, conductance and inductance from the finite element representation of electrostatic and magnetostatic problems. The method can be used to complement existing finite element software which utilizes a field approach, or can be used for determining such quantities without the requirement for intermediate determination of a potential distribution within the system. Expresses the quantities in terms of parameters which depend only on the materials used in the system and their geometric distribution. In multi‐electrode systems, the direct method allows for the determination of the entire capacitance, inductance or conductance matrix in a single factorization process, without the need for the repeated numerical determination and evaluation of the potential distribution for each electrode in turn. The direct solutions for capacitance and inductance can be used to derive expressions for the forces and torques within the system, using the principle of virtual work.
Transforming economies of Eastern Europe: an evaluation of the role and contribution of the small scale private sector (with specific reference to Poland)
Authors: Gordon Dickinson Paul
Published: July 2002

Examines the role and effect of the small scale private sector on Eastern Europe’s economic development, i.e. small private companies, partnerships and entrepreneurs, indicating why it is important in the reform programmes. Discusses the need for an entrenchment of the small scale private sector’s contribution to economic development, through adequate legislation and the right regulatory framework including a competition policy, and a commercial code for business formation and insolvency. Focuses mainly on Poland, and takes into account the author’s own views, observations, discussions and interviews whilst working in Poznan from 1996 to 1997. In particular, finds evidence of an abundance of innate entrepreneurial skills in Poland including the propensity for risk taking, and the presence of one of the best laid regulated economic climates of the transforming economies, although there is still a need for government to encourage small business into manufacturing.
European Union public procurement policy and electronic commerce: problems and opportunities
Authors: Erridge Ruth Fee Andrew , McIlroy John
Published: July 2002

Public procurement is one of the principal instruments used by the Commission to open up the European Single Market. This paper presents a critical assessment of public procurement policy in the context of developing policies on electronic commerce and the Government Procurement Agreement (GPA) within the World Trade Organisation (WTO). The paper focuses on how business can access public procurement opportunities in Europe, and what opportunities exist for improved electronic means of access to information. The proposed future for electronic tendering in Europe, SIMAP, is discussed and compared to similar systems in the USA. The paper suggests that a new legislative framework is required for public procurement and electronic commerce in Europe to ensure that governments and businesses do not suffer a competitive disadvantage in the electronic future of world trade.
Conflict management across cultural boundaries: a case analysis from a multinational bank
Authors: Darling John R. , Fogliasso Christine E.
Published: July 2002

Business today is increasingly being impacted by international considerations. This international impact is felt in areas such as locating the various sources of raw materials, coordinating production schedules with plants around the globe, selecting marketing strategies to be employed in various cultures, determining which financial decisions need to be made in a world market, and also how to best utilize a workforce rich in diversity of talents, backgrounds, and communication styles. This paper addresses the last of these considerations: namely, how to effectively manage a diverse workforce. In particular, this work is directed toward helping managers to deal with conflict in the workplace, and to effectively manage that conflict across cultural boundaries. A case situation involving a multinational bank with a diverse workforce is presented. The nature of conflict is discussed, and contributors to conflict explored. A variety of conflict management techniques is reviewed and discussed. Finally, a proposed nine‐step model for managing conflict is presented. The proposed model is then applied to the case situation to illustrate its practical applicability to business today.
Locating defects on shirt collars using image processing
Authors: Al‐Eidarous Mustafa
Published: July 2002

Recent developments in the hardware and software mean that the automation of visual fabric inspection tasks is becoming feasible at low cost. This paper investigates the techniques that can be used to solve the problem of repetitive, tedious and physically demanding human inspection for defects in shirt collars. The faults studied in this work are those found in nine types of defects that can be present on shirt collar panels. Two statistical methods: moving group average, and moving divided group average are proposed. In addition, highlighting and variance techniques are applied to an image with moving group average and signature counting. These techniques gave an indication of fast computation time to detect the defects on the image, which is needed in manufacturing, and could be applied to most automated inspection systems.
An experimental study of needle heating in sewing heavy materials using infrared radiometry
Authors: Liasi Evangelos , Du Ruxu , Simon Dan , Bujas‐Dimitrejevic Jasmina , Liburdi Frank
Published: July 2002

This paper presents an experimental study on needle heating in sewing heavy materials such as upholstery fabrics. In the experiments, infrared (IR) radiometry, high speed line scanning IR radiometry, and high speed IR radiometry are used to obtain thermal images of the needle during sewing. In particular, IR radiometry was used in lower speed sewing (approximately 500rpm). High speed IR and high speed line scanning IR radiometry were used for medium speed sewing (1,000‐2,000rpm). Using Taguchi’s design of experiment method, the effects of various factors are studied including needle conditions (sharp or blunt), sewing speeds, number of stitches per inch, material being sewn, and thread tension. It is found that even with air vortex cooling the needle may still reach high enough temperatures that may affect the sewing quality and even cause thread breakage. This was confirmed via a thread tensile testing experiment. An empirical model of the mean needle temperature is also proposed and tested.
Designing‐in of high value for manufacturers in the new millennium
Authors: Chen Ke‐Zhang
Published: July 2002

The Asia‐Pacific region has enjoyed robust economic growth in the last two decades and a substantial manufacturing network has been established in the region. The manufacturers in this region are now able to offer very good quality products cost‐effectively in the low‐end product category. But the recent regional financial turmoil, besides the increasingly integrated global economy and the emergence of regional trade pacts, has had an impact on the whole region and also presented many new challenges for businesses. Under this condition, manufacturers have to consider seriously how to win competition as they move into the new millennium. This paper applies axiomatic design to develop the guidelines for high value‐added activities. Manufacturers may discover their own weak points and develop their own core competencies or competitive priorities to drive change according to these guidelines.
Job Stressors and Their Effects on Physical Health, Emotional Health and
Job Satisfaction in a University
Authors: Dua Jagdish K.
Published: July 2002

All staff at the University of New England were sent a personal
particulars form and questionnaires designed to obtain information about
job‐related factors which acted as stressors for them, their general
stress, their emotional health, and their physical health. Factor
analysis of the job stressors questionnaires revealed that six factors,
namely, job significance, workload, work politics, interpersonal
dealings at work, work conditions, and university reorganization, were
the major stressors for the staff. In general, younger staff members
reported more job stress than older staff. Staff belonging to the
Faculty of Education, Nursing and Professional Studies at the Armidale
campus and general staff at the Armidale campus reported more job stress
than other staff. There was some indication that staff employed at the
higher job levels were less stressed than those employed at the lower
job levels and support staff. Both the job stress and non‐work stress
were associated with poor physical health, poor emotional health, and
high job dissatisfaction.
The diffusion, design and social shaping of production management information systems in Europe
Authors: Swan Jacky , Newell Sue , Robertson Maxine
Published: July 2002

Information systems for production management tend to be promoted by technology suppliers as standardised solutions which form a singular “best practice”. However, as these technologies are configurational, the notion of best practice is illusory. Data on the diffusion and design of information systems for production management across four European countries indicate distinctive national differences. It is argued that these can best be explained at two levels: first, national differences in the social institutional networks through which information about these systems is diffused socially shapes patterns of adoption and design; second pre‐existing patterns of work design and managerial practices may influence the degree of “fit” between particular design philosophies and prevailing organizational contexts in different countries. Differences in the particular roles of professional association networks and technology suppliers in the diffusion process are explained in terms of different patterns of knowledge sharing across countries.
Technology acceptance in the banking industry
Authors: Anandarajan Murugan , Igbaria Magid , Anakwe Uzoamaka P.
Published: July 2002

In the last decade, information technology has proven to be the major enabler that has helped multinational corporations to integrate their worldwide operations. However, studies show that many of these foreign subsidiaries, especially in less‐developed countries, under‐utilize their information systems, thus not making a significant contribution in improving the performance of organizations. Previous research, which investigated the factors that motivated individuals in accepting information technology, were conducted in developed countries. Since less‐developed countries differ culturally from developed countries, it is important to identify the factors which motivate individuals in these countries to accept as well as use information technology. This study seeks to investigate this issue. A comprehensive questionnaire on microcomputer acceptance and its resulting impact was collected from 88 users in six banks in Nigeria. The results suggest that social pressure is an important factor affecting microcomputer usage.
Supply‐chain management across the Internet
Authors: Graham Gary , Hardaker Glenn
Published: July 2002

The concepts of supply‐chain design and management have come to the fore, owing to the ever‐increasing complexity of the systems driving buyer‐supplier relations in both industrial and consumer‐based markets. The unprecedented levels of supply‐chain management complexity are partly attributed to the Internet, through its more recent business acceptance and commercial use. Deals with new competitive challenges being realised from the unprecedented speed of growth of the Internet and building commercially‐viable supply chains to meet the challenges faced by emerging virtual organisations.
The importance of information technology in port terminal operations
Authors: Kia M. , Shayan E. , Ghotb F.
Published: July 2002

Information technology has become an essential part of the rapid and accurate transfer and processing of enormous volumes of data processed in international transport firms and port organisations. The proper management of systems, which process this information and communicate it to those who manage port operations, is vital for efficient transport. This explains why container‐tracking systems are given high priority among operational computer applications in ports. Investigates the importance of information technology and its role in improving the operational systems in cargo handling. A computer simulation model is developed to compare two different operational systems – a container terminal equipped with electronic devices versus a terminal without such devices. The importance of information technology in supply‐chain management is also discussed.
Building customer relationships: do discount cards work?
Authors: McIlroy Andrea , Barnett Shirley
Published: July 2002

The relationship between customer loyalty and satisfaction, profitability and customer retention is described within the framework of relationship marketing. The importance of loyal customers and their impact on business profitability is undisputed, but it is more difficult to build customer retention than it may appear. Various strategies including loyalty schemes and discount cards are sometimes used in an effort to retain customers, but their success is questionable. A New Zealand hotel case study is presented which describes customer reactions to a discount card promotion. It was found that customers who purchased the card exhibited the characteristics of Morgan’s “mercenaries”. Although they had high satisfaction, their commitment to the company was low. However, in order to succeed, loyalty programmes need to develop “loyalists”, customers who have high satisfaction, high loyalty and who will stay and be supportive of the company.
Direct numerical simulation of an impinging jet into parallel disks
Authors: Satake Shin‐ichi , Kunugi Tomoaki
Published: July 2002

A direct numerical simulation code with cylindrical geometry has been developed. A direct numerical simulation (DNS) of an impinging round jet into parallel disks is performed for a Reynolds number of 10,000 based on the nozzle exit velocity and the nozzle diameter (D). Mean flow variables, turbulent intensity, pressure distribution and turbulent kinetic energy budgets are obtained at various radial locations. The present DNS results are in fairly good agreement with the two‐dimensional PTV measurements by Nishino and co‐workers in 1996. Some flow features of this impinging round jet regarding a turbulent transition process are discussed.
An approximate method for oxygen diffusion in a sphere with simultaneous absorption
Authors: Ahmed S.G.
Published: July 2002

The oxygen diffusion problem is usually formulated in two stages: first, the steady state and second, the moving boundary stage. In this paper, we will consider the solution of the second stage in which a new semi‐analytical method for solving such a problem was developed. The present method starts by assuming a polynomial representing the profile of oxygen concentration, and then by some mathematical manipulation a system of linear equations is obtained. Numerical solution for the system with a simple scheme relating the moving boundary and its velocity leads to the unknown functions in the assumed polynomial.
Understanding and managing the dynamics of linked crisis events
Authors: Ren Chiang H.
Published: July 2002

Presents a macro analysis of the dynamics of temporally linked crisis events and the non‐linear effects resulting from the linkage. The nature of crisis is explored as a singular conceptual construct, and four forms of linkage between crises are assessed. Specific emphasis is placed on how such linkages amplify the total damage upon society and lengthen the duration of the cumulative recovery effort. Based on the assessment, new points of strategic planning focus are identified to drive continued empirical research and to support the development of future operational plans in crisis response.
The Internet as a “virtual cultural region”: are extant cultural classification schemes appropriate?
Authors: Johnston Kevin , Johal Parminder
Published: July 2002

This paper examines the concept of the Internet as a virtual cultural region with its own demographics and psychographics. Longitudinal studies of the changing make up of Internet users have been running for much of the 1990s and market intelligence companies have been applying their proprietary segmentation models to this data and also creating new models specifically for the Internet. At a more sociological level, what are the cultural norms and cutoms of the population of the Internet cultural region? This paper complements the market intelligence research by an investigation into the applicability of cultural classification schemes as exemplified by Hofstede with a view to information extant and prospective Internet involvement. Finally, practical recommendations are made in order to reduce the risk of activities likely to cause irritation of and non‐response from this burgeoning new market.
Wafer level packaging of compliant, chip size ICs
Authors: Fjelstad Joseph , DiStefano Thomas , Faraci Anthony
Published: July 2002

The concept of packaging integrated circuits while they are still in wafer form has captured the imagination of semiconductor manufacturers and packagers around the globe. One such concept, referred to as wide area vertical expansion (WAVETM) technology promises to provide a relatively easy method for cost effectively interconnecting ICs while still on the wafer. Moreover the fundamental technology is amenable to the production of “virtual wafers” where individual IC chips can be assembled en masse. The virtual wafer variation also allows for die shrink to occur, while the IC package footprint remains constant. The technology is based on concepts that allow for the mass assembly and production of compliant packages both directly on the wafer and in “virtual wafer” format where individual chips are bonded directly to the flexible pellicle. This paper examines this important new packaging technology concept in terms of the process and device and the implications and future directions the technology is likely to take.
Frequencies of amino acid strings in globular protein sequences indicate suppression of blocks of consecutive hydrophobic residues
Authors: Schwartz Russell , Istrail Sorin , King Jonathan
Published: July 2002

Patterns of hydrophobic and hydrophilic residues play a major role in protein folding and function. Long, predominantly hydrophobic strings of 20–22 amino acids each are associated with transmembrane helices and have been used to identify such sequences. Much less attention has been paid to hydrophobic sequences within globular proteins. In prior work on computer simulations of the competition between on‐pathway folding and off‐pathway aggregate formation, we found that long sequences of consecutive hydrophobic residues promoted aggregation within the model, even controlling for overall hydrophobic content. We report here on an analysis of the frequencies of different lengths of contiguous blocks of hydrophobic residues in a database of amino acid sequences of proteins of known structure. Sequences of three or more consecutive hydrophobic residues are found to be significantly less common in actual globular proteins than would be predicted if residues were selected independently. The result may reflect selection against long blocks of hydrophobic residues within globular proteins relative to what would be expected if residue hydrophobicities were independent of those of nearby residues in the sequence.
Probing protein conformation with a minimal photochemical reagent
Authors: Craig Patricio O. , Ureta Daniela B. , Delfino José M.
Published: July 2002

3H‐diazirine (3H‐DZN), a photoreactive gas similar in size to water, was used to probe the topography of the surface and inner space of proteins. On photolysis 3H‐DZN generates 3H‐methylene carbene, which reacts unselectively with its molecular cage, inserting even into C‐H bonds. Labeling of bovine α‐lactalbumin (α‐LA, MW: 14,200) with 1 mM 3H‐DZN yielded 0.0041 mol CH2/mol of protein, in agreement with the expectation for an unspecific surface‐labeling phenomenon. The cooperative urea‐induced unfolding of α‐LA, as monitored by the extent of 3H‐methylene labeling, agrees with that measured by circular dichroism spectroscopy in the far and near ultraviolet regions. At 8 M urea, the unfolded state U was labeled 25–30% more than the native state N primarily because of the increase in the accessible surface area (ASA) of the protein occurring upon unfolding. However, this result lies below the ∼100% increment expected from theoretical estimates of ASA of state U. Among other factors, most likely the existence of a residual structure in U, that involves helices H2 and H4 of the α subdomain, might account for this fact, as shown by a comparative analysis of peptide labeling patterns of N and U samples. In this paper, we demonstrate the usefulness of the 3H‐methylene labeling method to monitor conformational transitions and map solvent accessibility along the polypeptide sequence, thus opening the possibility of outlining structural features of nonnative states (i.e., denatured states, molten globule). We anticipate that this technique also would help to identify ligand binding and oligomerization sites in proteins.
Three‐Phase Solutions of the Kadomtsev–Petviashvili Equation
Authors: Dubrovin B. A. , Flickinger Ron , Segur Harvey
Published: July 2002

The Kadomtsev–Petviashvili (KP) equation is known to admit explicit periodic and quasiperiodic solutions with N independent phases, for any integer N, based on a Riemann theta‐function of N variables. For N=1 and 2, these solutions have been used successfully in physical applications. This article addresses mathematical problems that arise in the computation of theta‐functions of three variables and with the corresponding solutions of the KP equation. We identify a set of parameters and their corresponding ranges, such that every real‐valued, smooth KP solution associated with a Riemann theta‐function of three variables corresponds to exactly one choice of these parameters in the proper range. Our results are embodied in a program that computes these solutions efficiently and that is available to the reader. We also discuss some properties of three‐phase solutions.
Spontaneous arousal activity in infants during NREM and REM sleep
Authors: McNamara Frances , Lijowska Anna S. , Thach Bradley T.
Published: July 2002

The infant arousal response involves subcortical and cortical responses occurring as a sequence of stereotyped behaviour regardless of the eliciting stimulus. The spontaneous activity of these responses during sleep, however, is uncertain. We examined the spontaneous arousal pattern in normal infants to determine the sequence of responses, and to examine their periodicity and the effects of sleep state. We performed a nap polysomnographic study on 10 normal infants between 2 and 10 weeks of age. Electroencephalographic and electro‐oculographic activity, and respiratory airflow and movements were measured, and video recordings were made throughout each study. Different levels of arousal behaviour were examined. We found that spontaneous arousal activity occurred frequently and the majority of responses occurred as a sequence involving an augmented breath followed by a startle and then cortical arousal. Subcortical arousals as reflected by augmented breaths and startles were more common than cortical arousals. Additionally, augmented breaths followed by apnoea were recorded and were not usually associated with other arousal responses. All of the responses occurred periodically either as bursts of activity or as isolated responses. Each of the responses occurred more frequently during rapid eye movement (REM) sleep than during non‐rapid eye movement (NREM) sleep. We conclude that there is an endogenous rhythm of spontaneous activity in infants involving excitatory processes from the brainstem, which may or may not be closely followed by cortical excitation. The spontaneous arousal responses occur periodically but with a high level of irregularity and the level of activity is affected by sleep state.
D1 and D2 receptor‐mediated dopaminergic modulation of visual responses in cat dorsal lateral geniculate nucleus
Authors: Zhao Yongqiang , Kerscher Nicolas , Eysel Ulf , Funke Klaus
Published: July 2002

The modulatory effects of dopamine (DA) on the visual responses of relay cells of the dorsal aspect of cat lateral geniculate nucleus (dLGN) were tested using local micro‐iontophoretic application of DA and application of the receptor‐specific agonists SKF38393 (SKF, D1/D5) and quinpirole (QUIN, D2/D3/D4) in the anaesthetized alcuronium‐treated cat. The effects of DA and QUIN were clearly dose‐dependent: small amounts caused a weak and transient facilitation of visual activity (10–30 % increase) preferentially in Y‐type relay cells, which changed to a moderate reduction of visual responses when the dose was increased (50 %, maximal 70 %). The effect of SKF was mainly suppressive and increased with the amount of drug applied (up to 90 % reduction). The selective antagonists SCH23390 (SCH, D1) and sulpiride (SULP, D2) reduced the effects of co‐applied DA agonists. We found little evidence for a specific dopaminergic modulation of the surround inhibition (stimulus‐driven lateral inhibition) although DA slightly facilitated the transmission of weak signals (small stimuli). Nevertheless, some dopaminergic effects seem to be mediated via inhibitory interneurons regulating the strength of sustained or recurrent inhibition. Application of DA agonists during blockade of GABAA receptors indicates a direct suppression of relay cells via D1 receptors, an excitation of relay cells via D2 receptors and ‐ with increasing amounts of D2 agonist ‐ probably also an excitation of inhibitory interneurons, which results in an indirect inhibition of dLGN relay cells (predominantly of the X‐type). The results are discussed in relation to the impairment of visual functions in Parkinson's disease.
Change in length of relaxed muscle fascicles and tendons with knee and ankle movement in humans
Authors: Herbert R. D. , Moseley A. M. , Butler J. E. , Gandevia S. C.
Published: July 2002

Ultrasonography was used to measure changes in length of muscle fascicles in relaxed human tibialis anterior and gastrocnemius during passively imposed changes in joint angle. Changes in the length of muscle fascicles were compared to changes in the length of the whole muscle‐tendon units calculated from joint angles and anthropometric data. Relaxed muscle fascicles underwent much smaller changes in length than their muscle‐tendon units. On average, muscle fascicles in tibialis anterior [saw] 55 ± 13 % (mean ±s.d.) of the total change in muscle‐tendon length. This indicates nearly half of the total change in muscle‐tendon length was taken up by stretch of tendon. In gastrocnemius, which has relatively long tendons, only 27 ± 9 % of the total change in muscle‐tendon length was transmitted to muscle fascicles. Thus, the tendency for passive movement to be taken up by the tendon was greater for gastrocnemius than tibialis anterior (P = 0.002). For these muscles, the relatively large changes in tendon length across much of the physiological range of muscle‐tendon lengths could not wholly be explained by tendon slackness, changes in fibre pennation, or stretch or contraction history of the muscle. Our data confirm that when joints are moved passively, length changes [seen] by muscle fascicles can be much less than changes in the distance between muscle origin and insertion. This occurs because tendons undergo significant changes in length, even at very low forces.
Different temporal processing of sensory inputs in the rat thalamus during quiescent and information processing states in vivo
Authors: Castro‐Alamancos Manuel A.
Published: July 2002

Sensory inputs from the whiskers reach the primary somatosensory thalamus through the medial lemniscus tract. The main role of the thalamus is to relay these sensory inputs to the neocortex according to the regulations dictated by behavioural state. Intracellular recordings in urethane‐anaesthetized rats show that whisker stimulation evokes EPSP‐IPSP sequences in thalamic neurons. Both EPSPs and IPSPs depress with repetitive whisker stimulation at frequencies above 2 Hz. Single‐unit recordings reveal that during quiescent states thalamic responses to repetitive whisker stimulation are suppressed at frequencies above 2 Hz, so that only low‐frequency sensory stimulation is relayed to the neocortex. In contrast, during activated states, induced by stimulation of the brainstem reticular formation or application of acetylcholine in the thalamus, high‐frequency whisker stimulation at up to 40 Hz is relayed to the neocortex. Sensory suppression is caused by the depression of lemniscal EPSPs in relatively hyperpolarized thalamocortical neurons. Sensory suppression is abolished during activated states because thalamocortical neurons depolarize and the depressed lemniscal EPSPs are able to reach firing threshold. Strong IPSPs may also contribute to sensory suppression by hyperpolarizing thalamocortical neurons, but during activated states IPSPs are strongly reduced altogether. The results indicate that the synaptic depression of lemniscal EPSPs and the level of depolarization of thalamocortical neurons work together in thalamic primary sensory pathways to suppress high‐frequency sensory inputs during non‐activated (quiescent) states while permitting the faithful relay of high‐frequency sensory information during activated (processing) states.
A comparison of currents carried by HERG, with and without coexpression of MiRP1, and the native rapid delayed rectifier current. Is MiRP1 the missing link?
Authors: Weerapura Manjula , Nattel Stanley , Chartier Denis , Caballero Ricardo , Hébert Terence E.
Published: July 2002

Although it has been suggested that coexpression of minK related peptide (MiRP1) is required for reconstitution of native rapid delayed‐rectifier current (IKr) by human ether‐a‐go‐go related gene (HERG), currents resulting from HERG (IHERG) and HERG plus MiRP1 expression have not been directly compared with native IKr. We compared the pharmacological and selected biophysical properties of IHERG with and without MiRP1 coexpression in Chinese hamster ovary (CHO) cells with those of guinea‐pig IKr under comparable conditions. Comparisons were also made with HERG expressed in Xenopus oocytes. MiRP1 coexpression significantly accelerated IHERG deactivation at potentials negative to the reversal potential, but did not affect more physiologically relevant deactivation of outward IHERG, which remained slower than that of IKr. MiRP1 shifted IHERG activation voltage dependence in the hyperpolarizing direction, whereas IKr activated at voltages more positive than IHERG. There were major discrepancies between the sensitivity to quinidine, E‐4031 and dofetilide of IHERG in Xenopus oocytes compared to IKr, which were not substantially affected by coexpression with MiRP1. On the other hand, the pharmacological sensitivity of IHERG in CHO cells was indistinguishable from that of IKr and was unaffected by MiRP1 coexpression. We conclude that the properties of IHERG in CHO cells are similar in many ways to those of native IKr under the same recording conditions, and that the discrepancies that remain are not reduced by coexpression with MiRP1. These results suggest that the physiological role of MiRP1 may not be to act as an essential consituent of the HERG channel complex carrying native IKr.
Selective reduction by dopamine of excitatory synaptic inputs to pyramidal neurons in primate prefrontal cortex
Authors: Urban Nathaniel N. , González‐Burgos Guillermo , Henze Darrell A. , Lewis David A. , Barrionuevo German
Published: July 2002

We have employed in vitro physiological methods to investigate dopaminergic modulation of excitatory synaptic transmission in monkey prefrontal cortex (PFC) circuits. We show that combined activation of D1‐like and D2‐like dopamine receptors results in the reduction of extracellular stimulation‐evoked isolated EPSCs in layer 3 pyramidal neurons. Using paired recordings from synaptically connected pyramidal neurons we have determined the basic properties of unitary synaptic connections between layer 3 pyramids in the primate PFC and, interestingly, we found that dopamine does not reduce synaptic transmission between nearby pairs of synaptically coupled PFC pyramidal neurons. This input specificity may be a critical aspect of the dopaminergic regulation of recurrent excitatory circuits in the PFC.
Determination of Heat Transfer Coefficients Using a 1-D Flow Model Applied to Irregular Shaped Cooling Channels in Pressure Diecasting
Authors: Clark L. D. , Davey K. , Rosindale I. , Hinduja S.
Published: July 2002

A mesh partitioning strategy is presented which facilitates the application of boundary conditions to irregular shaped cooling channels in the pressure diecasting process. The strategy is used to partition a boundary element mesh, but can also be applied to the surface of a cooling channel bounded by a finite element mesh. The partitioning of the mesh into a series of element packs enables a one-dimensional flow model to be applied to the coolant. The flow model is used in conjunction with a steady-state thermal model which initially assumes that no boiling is taking place on the die/coolant interface. Values of bulk temperature, pressure, and velocity in the coolant are thus ascertained. This information, together with die temperatures, is then used in empirical relationships which model the various heat transfer mechanisms, including nucleate and transitional film boiling, between die and coolant. Effective heat transfer coefficients are calculated and applied at the die/coolant interface. The steady-state thermal code and the empirical boiling model are then used iteratively until stable values for the effective heat transfer coefficients are obtained. The models are tested by casting a small thin component using a die with conventional cooling channels and also using a novel die with irregular shaped cooling channels running on a hot chamber proprietary die casting machine. Simulation results are shown and experimental results using the hot chamber pressure die casting machine are reported. [S1087-1357(00)02302-9]
Three-Dimensional Finite Element Analysis of Glenoid Replacement Prostheses: A Comparison of Keeled and Pegged Anchorage Systems
Authors: Lacroix D. , Murphy L. A. , Prendergast P. J.
Published: July 2002

Glenoid component loosening is the dominant cause of failure in total shoulder arthroplasty. It is presumed that loosening in the glenoid is caused by high stresses in the cement layer. Several anchorage systems have been designed with the aim of reducing the loosening rate, the two major categories being “keeled” fixation and “pegged” fixation. However, no three-dimensional finite element analysis has been performed to quantify the stresses in the cement or to compare the different glenoid prosthesis anchorage systems. The objective of this study was to determine the stresses in the cement layer and surrounding bone for glenoid replacement components. A three-dimensional model of the scapula was generated using CT data for geometry and material property definition. Keeled and pegged designs were inserted into the glenoid, surrounded by a 1-mm layer of bone cement. A 90 deg arm abduction load with a full muscle and joint load was applied, following van der Helm (1994). Deformations of the prosthesis, stresses in the cement, and stresses in the bone were calculated. Stresses were also calculated for a simulated case of rheumatoid arthritis (RA) in which bone properties were modified to reflect that condition. A maximum principal stress-based failure model was used to predict what quantity of the cement is at risk of failure at the levels of stress computed. The prediction is that 94 percent (pegged prosthesis) and 68 percent (keeled prosthesis) of the cement has a greater than 95 percent probability of survival in normal bone. In RA bone, however, the situation is reversed where 86 percent (pegged prosthesis) and 99 percent (keeled prosthesis) of the cement has a greater than 95 percent probability of survival. Bone stresses are shown to be not much affected by the prosthesis design, except at the tip of the central peg or keel. It is concluded that a “pegged” anchorage system is superior for normal bone, whereas a “keeled” anchorage system is superior for RA bone. [S0148-0731(00)01804-5]
A Study on Fusion Repair Process for a Precipitation Hardened IN738 Ni-Based Superalloy
Authors: Kim Dae-Young , Hwang Jong-Hyun , Kim Kwang-Soo , Youn Joong-Geun
Published: July 2002

Several fusion repair processes such as laser cladding, laser welding and gas tungsten arc welding have been taken into consideration for repairing IN738 precipitation hardened Ni-based superalloy material. Effect of heat input on weld cracking susceptibility has been studied to obtain optimum condition for crack-free welds. Variations in cracking susceptibility as a function of welding heat input is discussed with reference to metallurgical characteristics of the welds. [S0742-4795(00)02003-2]
Structural-Acoustic Coupling Analysis of the Vehicle Passenger Compartment with the Roof, Air-Gap, and Trim Boundary
Authors: Kang Sang Wook , Lee Jang Moo , Kim Seock Hyun
Published: July 2002

A theoretical model is made to investigate the coupling effects of the trim and air gap on the frequency response characteristics of a passenger compartment. With the model, a parametric study is carried out to understand the relation between the acoustic response of the cavity and the design variables associated with the roof, trim, and air gap between the two. The validity of theoretical formulations is verified through a comparison between the theoretical results and the finite element analysis results. Finally, an experiment for a simplified compartment cavity model is performed to confirm the theoretical results. This study reveals that the resonance peak level of an acoustic mode, which has a nodal surface parallel to the trim, can be significantly reduced by properly designing the trim mass and the gap thickness of the trim-air gap system. [S0739-3717(00)00303-2]
Modeling and Control of Acoustic Ducts
Authors: Pota H. R. , Kelkar A. G.
Published: July 2002

This paper presents closed-form mathematical models for an acoustic duct with general boundary conditions. These infinite-dimensional models are derived using symbolic computations. A new method to obtain finite dimensional approximations of infinite-dimensional models using quartic functions is presented. The theoretical models are compared with the experimental data obtained for the KSU duct. The experimental results of a new robust broadband feedback controller, designed using passivity-based techniques, are presented. The controller design is shown to be robust to the unmodeled dynamics and parametric uncertainty.
Nonlinear Control for Missile Terminal Guidance
Authors: Liaw Der-Cherng , Liang Yew-Wen , Cheng Chiz-Chung
Published: July 2002

Variable Structure Control (VSC) technique is applied to the design of robust homing missile guidance laws. In the design procedure, the target’s maneuver is assumed to be unpredictable and is considered as disturbances. Guidance laws are then proposed to achieve the interception performance for both cases of longitude-axis control being available and unavailable. The proposed guidance laws are continuous which alleviate chattering drawback by classic VSC design. Results are obtained and compared with those by realistic true proportional navigation design to illustrate the benefits of the proposed design. [S0022-0434(00)00604-3]