Showing papers by "Northampton Community College published in 2002"

Incidence and risk factors for microbial keratitis in Hong Kong: comparison with Europe and North America.

Abstract: Purpose To establish the incidence, etiology and risk factors for microbial keratitis (MK) in Hong Kong. Methods Two hundred and twenty-three new cases of presumed MK were recruited over a period of 17 months and comprehensive microbiologic studies performed. A nested case-control study was pursued for patients wearing contact lenses (CLW) to determine risk factors for MK with regards to types of CLW and hygiene practice. Results Of the 223 patients recruited, 59 (26%) wore contact lenses. Corneal scrapes yielded positive cultures from 77 patients (35% overall, 56 non-CLW, 21 CLW). Two hundred and six CLW volunteers were recruited to participate in the case-control study, of whom 135 were matched with 45 CLW patients. The annual incidence of MK was 0.63 per 10 000 population and 3.4 per 10 000 CLW with rates for daily, extended and rigid lens wear of 3.09, 9.30 and 0.44 per 10 000 CLW respectively. Pseudomonas aeruginosa was the dominant bacterial pathogen. Six cases of Acanthamoeba keratitis occurred, five in CLW (incidence 0.33 per 10 000 CLW) and one following corneal abrasion. Non-CLW developed MK at a peak age of 73, which is 10 years younger than expected for Scotland and USA. Conclusions Previous ocular surface disease and trauma were the main risk factors for MK in Hong Kong. CLW appears at least as safe as that found in Scotland and the USA. Acanthamoeba keratitis was detected but with an incidence rate five times lower than Scotland. Factors predisposing hydrogel CLWs to MK, that were statistically significant, included overnight wear, poor hygiene and smoking.

Organizational commitment: a critique of the construct and measures

Abstract: Organizational commitment has been at the centre of studies into individual and organizational performance for several decades. During this time, much has happened to the ways in which organizations behave, including the evolution of new forms of employee relations and new psychological contracts. Against a transformational background for organizations, developments in the ways that commitment is measured have been incremental and arguably detached from the broader context of ‘new deals’ for employees. This paper examines classical approaches to defining and measuring organizational commitment and, in the context of strategic human resource management, argues for its continued importance. Classic approaches, however, are criticized on the basis of diminished utility in light of revised employee–organization linkages. Suggestions for improving the relevance of commitment research to contemporary management research and practice are given.

Increased systolic blood pressure in rats induced by a maternal low-protein diet is reversed by dietary supplementation with glycine.

Abstract: When rat dams consume a diet low in protein during pregnancy, their offspring develop high blood pressure. On a low-protein diet, the endogenous formation of the amino acid glycine is thought to become constrained. Glycine may become conditionally essential, as its rate of endogenous formation is inadequate to meet metabolic needs, and may be limiting for the normal development of the fetus. In the present study, five groups of Wistar rats were provided during pregnancy with one of five diets: a control diet containing 18% (w/w) casein (CON), a low-protein diet containing 9% casein (MLP), or the low-protein diet supplemented with 3% glycine (MLPG), alanine (MLPA) or urea (MLPU). The offspring were weaned on to standard laboratory chow, and blood pressure was measured at 4 weeks of age. Blood pressure was significantly increased in the MLP, MLPA and MLPU groups compared with the CON group, but for the MLPG group blood pressure was not significantly different from CON. Compared with the CON group, body weight was significantly reduced for the MLP, MLPA and MLPG groups, but for the MLPU group body weight was not different from CON. These data show that different forms of non-essential dietary nitrogen, when consumed during pregnancy, exert different effects upon the growth and function of the offspring. The availability of glycine appears to be of critical importance for normal cardiovascular development.

Factors affecting the initiation of breastfeeding: implications for breastfeeding promotion

Abstract: Breastfeeding rates in the United Kingdom (UK) are one of the lowest in the developed world and certainly the lowest in Europe. There have been numerous studies of breastfeeding in the UK, most of which have adopted a quantitative approach, and they have largely focused on obstetric or socio-demographic factors in the decision to breastfeed. Whilst these studies have an important role to play, this paper draws on a study that adopts a qualitative methodology to explore women's personal experiences and perceptions of breastfeeding. A qualitative study of 19 primagravidae was undertaken and completed in 1998. Participants were recruited to the study via 12 antenatal clinics in the West Midlands, England, UK. Their ages ranged from 16 to 30 years and the majority described themselves as 'white'. The majority of participants were in paid employment in a variety of occupations. The study was prospective in design. Participants were interviewed three times either during pregnancy or after childbirth: the first stage was between 6 and 14 weeks of pregnancy; the second stage was between 34 and 39 weeks; and the third stage was between 6 and 14 weeks after childbirth. The data indicate that there are several factors affecting breastfeeding initiation. First, infant feeding decisions seem to be made prior to, or irrespective of, contact with health professionals. Secondly, the data suggest that health promotion campaigns in the UK have been influential in their ability to educate women about the benefits of breastfeeding. However, this did not dissuade participants from formula feeding once their decision was made. The desire for paternal involvement also seemed to be another influential factor; fathers were either seen as able to alleviate the daily grind of early motherhood, or there was a desire for 'shared parenting'. Finally, some of the formula feeding women expressed a strong desire to re-establish their identities as separate individuals and as 'non-mothers'.

Microwave acoustic materials, devices, and applications

Abstract: This paper surveys applications of acoustic waves in microwave devices. After a general and historical introduction to bulk acoustic waves (BAWs), surface acoustic waves (SAWs), practical wave types, and acoustoelectric transducers, a review is given of technologically important materials for microwave acoustic applications. Following this, we discuss BAW and SAW microwave devices and their technologies. Specifically reviewed are thin-film resonators and filters, transversal filters, and filters for correlative analog signal processing. Finally, an overview of the most important microwave applications is given, along with manufacturing and packaging issues.

Salivary antioxidants and periodontal disease status.

Abstract: Periodontal disease is a common chronic adult condition. The bacterium Porphyromonas gingivalis has been implicated in the aetiology of this disease, which causes destruction of the connective tissue and bone around the root area of the tooth. It has been observed that invading P. gingivalis bacteria trigger the release of cytokines such as interleukin 8 and tumour necrosis factor a, leading to elevated numbers and activity of polymorphonucleocytes (PMN). As a result of stimulation by bacterial antigens, PMN produce the reactive oxygen species (ROS) superoxide via the respiratory burst as part of the host response to infection. Patients with periodontal disease display increased PMN number and activity. It has been suggested that this proliferation results in a high degree of ROS release, culminating in heightened oxidative damage to gingival tissue, periodontal ligament and alveolar bone. Antioxidant constituents in plasma have been well-documented, being chiefly ascorbate, albumin and urate, and these are known to display sensitivity to dietary antioxidant intakes. The concentration of antioxidants in saliva does not appear to mirror those of plasma. The extent of dietary influence upon salivary antioxidant status is unclear. Urate is the predominant salivary antioxidant, with albumin and ascorbate providing minor contributions. Previous research has found reduced salivary antioxidant activity in patients suffering from periodontal disease. An improved understanding of the role antioxidants play in periodontitis, and the influence of nutrition on antioxidant status, may lead to a possible nutritional strategy for the treatment of periodontal disease.

Optimal investment strategies and risk measures in defined contribution pension schemes

Abstract: In this paper, we derive a formula for the optimal investment allocation (derived from a dynamic programming approach) in a defined contribution (DC) pension scheme whose fund is invested in n assets. We then analyse the particular case of n=2 (where we consider the presence in the market of a high-risk and a low-risk asset whose returns are correlated) and study the investment allocation and the downside risk faced by the retiring member of the DC scheme, where optimal investment strategies have been adopted. The behaviour of the optimal investment strategy is analysed when changing the disutility function and the correlation between the assets. Three different risk measures are considered in analysing the final net replacement ratios achieved by the member: the probability of failing the target, the mean shortfall and a value at risk (VaR) measure. The replacement ratios encompass the financial and annuitisation risks faced by the retiree. We consider the relationship between the risk aversion of the member and these different risk measures in order to understand better the choices confronting different categories of scheme member. We also consider the sensitivity of the results to the level of the correlation coefficient.

Life Cycle Heterogeneity in Animal Models of Human Papillomavirus-Associated Disease

Abstract: Animal papillomaviruses are widely used as models to study papillomavirus infection in humans despite differences in genome organization and tissue tropism. Here, we have investigated the extent to which animal models of papillomavirus infection resemble human disease by comparing the life cycles of 10 different papillomavirus types. Three phases in the life cycles of all viruses were apparent using antibodies that distinguish between early events, the onset of viral genome amplification, and the expression of capsid proteins. The initiation of these phases follows a highly ordered pattern that appears important for the production of virus particles. The viruses examined included canine oral papillomavirus, rabbit oral papillomavirus (ROPV), cottontail rabbit papillomavirus (CRPV), bovine papillomavirus type 1, and human papillomavirus types 1, 2, 11, and 16. Each papillomavirus type showed a distinctive gene expression pattern that could be explained in part by differences in tissue tropism, transmission route, and persistence. As the timing of life cycle events affects the accessibility of viral antigens to the immune system, the ideal model system should resemble human mucosal infection if vaccine design is to be effective. Of the model systems examined here, only ROPV had a tissue tropism and a life cycle organization that resembled those of the human mucosal types. ROPV appears most appropriate for studies of the life cycles of mucosal papillomavirus types and for the development of prophylactic vaccines. The persistence of abortive infections caused by CRPV offers advantages for the development of therapeutic vaccines.

Development of a simplified version of the multiple errands test for use in hospital settings

Abstract: Problems with executive functioning may have catastrophic consequences following brain injury. Valid neuropsychological assessment procedures are required if the nature and extent of these are to be understood. However, some existing measures do not adequately reflect how executive impairments are manifested in the context of everyday functioning. Shallice and Burgess (1991) described one procedure, the Multiple Errands Test (MET), which did attain this goal. While successful, it was designed for people who performed within or above the normal range when tested using existing psychometric measures: however, it is acknowledged that many patients seen in routine clinical practice perform below normal limits. Furthermore, while the procedure was carried out in a public place a range of constraints may prevent this with some patients. In this paper the utility of a simplified MET designed for use within a hospital environment is explored. Twenty neurologically healthy participants and 20 people with acquired brain injury took part. People with acquired brain injury were clearly discriminated from healthy controls through the number of errors made. Furthermore, one category of error proved highly predictive of difficulties attributable to executive dysfunction observed in the context of everyday living. While one other test correlated almost as well with these difficulties, it was argued that MET methodology is more advantageous to clinicians regarding assessment and rehabilitation.

Consumer misbehaviour: an exploratory study of shopliftin

Abstract: Although customer theft is traditionally researched from a criminological or psychological perspective, this paper investigates shoplifting as consumer behaviour, demonstrating that well-defined models of normal consumer behaviour can be applied to aberrant behaviour such as shop theft. Empirical research is used to show how adults and teenagers form belief systems that amount to rational intentions in the decision to shoplift. The theory of planned behaviour (Ajzen, 1991) was used as the basis for two self-report surveys which investigated the interaction between consumers' attitudes and beliefs about shoplifting and their perceptions of retail security. The first survey utilised a sample of shoppers from the South East Midlands; the second a sample of school students from the same area (861 respondents in total, 109 respondents admitting to shoplifting in the previous year). Both studies indicate that the decision to shoplift is influenced by pro-shoplifting attitudes, social factors, opportunities for shoplifting and perceptions of low risks of apprehension. This implies that the deterrent messages we use must be reassessed. Copyright © 2002 Henry Stewart Publications.

Experiences of addiction and recovery: the case for subjective accounts

Abstract: In this paper we argue that psychology must address issues of subjective experience in accounting for addictive behaviour problems, and further, that self and identity are integral to such experiences. While the importance of self and identity issues is often recognised implicitly at the level of therapeutic practice, the extent of their involvement, and the nature of their relationship with other factors, is not yet fully understood at the level of theory and research. We offer a case for addressing this problem through the collection and analysis of subjective accounts. This is because we think that any understanding of the relationship between addiction, self and identity should be informed by participants' own accounts of their experiences of addictive behaviour problems. This argument is supported here by an account of observational data collected at a residential addictions treatment centre. The data were analysed using the IPA (Interpretative Phenomenological Analysis) approach. This represents a n...

Interactions between aeolian and fluvial systems in dryland environments

Abstract: Historically, fluvial and aeolian processes in dryland environments have been viewed as mutually exclusive. However, recent research indicates that in many regions dryland aeolian and fluvial systems do not operate independently. There are interactions between the two systems that have important implications for the geomorphology of the landscape. This paper reviews the factors controlling the transfer of sediments between aeolian and fluvial systems, focusing on moisture availability, sediment supply and the magnitude/frequency characteristics of fluvial and aeolian events. We conclude by highlighting areas of future research that will contribute greatly to our understanding of aeolian-fluvial relationships in dryland areas.

An investigation of the correlations between aggression, impulsiveness, social problem-solving, and alcohol use

Abstract: Impulsivity has been shown to predict aggression and heavy drinking in males, and poor social problem-solving has been identified as a potential mediating variable in this relationship. We set out to investigate the inter-relationships among impulsiveness, social problem-solving, aggression, and alcohol use in a non-offender sample of British males (N = 70). Of our proposed relationships, only two were significant: higher impulsivity was related to poorer social problem-solving, and poorer social problem-solving was related to greater aggression. Combining impulsivity and social problem-solving indicated that poor social problem-solving, not impulsivity, was what exerted the influence over aggression in this sample. Impulsivity perhaps presents an obstacle to learning in the early developmental years, and the legacy of poor problem-solving is what later contributes to aggression.

Transnational Television in Europe: The Role of Pan-European Channels

Abstract: j This article analyses the pan-European television industry in the context of the debate on globalization. Pan-European channels are a minority of transnational channels that broadcast across Europe. Their emergence over the last two decades has been made possible by a mix of commercial, regulatory and technological factors. Pan-European television channels can be distinguished by their content, type of ownership and market strategy. Since the mid-1990s, many pan-European channels have operated a shift in strategy and have begun to localize their pan-European feed. This article identifies four types of localization: local advertising, dubbing or subtitling, local programming and the local opt-out. Taking Eurosport and MTV as examples, I have illustrated the practices of localization and explain why some channels engage more in this than others. Localization can be seen as evidence of the vast differences that persist between national cultures. However, I have argued that localization facilitates the process of globalization because it allows transnational media players to overcome cultural diversity and operate efficiently in a multinational environment. j

A Multi-State Model of Disability for the United Kingdom: Implications for Future Need for Long-Term Care for the Elderly

Abstract: This paper develops a multiple state model to project the number of people with disabilities in the United Kingdom over the next 35 years, thereby identifying implications for demand for long-term care for the elderly in the future.The model requires three types of data: prevalence rate data, transition rate data and trends data. Recent trends in healthy life expectancy data are used to frame the assumptions made regarding changes in the disability rates of the U.K. population in the future.Although there will be a large increase in the number of elderly people in the U.K. over the next 35 years, the projections suggest that the implications for the number of elderly people requiring long-term care could be ameliorated by a reduction in the proportion of older people who are severely disabled.

Reproduction of relief patterns

Abstract: A relief master is formed by assembly of previously molded, machined, or otherwise fabricated relief structures. The relief structures may be quite small and include a relief geometry, i.e., a topology of interest, and a positioning feature. The relief structures are mounted on a rigid (e.g., metal) substrate that includes a plurality of positioning features complementary to the positioning features in the relief structures. The relief master is assembled through selective application and positioning of the small-scale relief structures, and can then be used as a pattern for diverse surface replication processes, including the fabrication of durable metal mold faces for casting, embossing, compression molding, and injection molding of complex patterned surfaces.

An autosampling differential scanning calorimeter instrument for studying molecular interactions.

Abstract: A new ultrasensitive differential scanning calorimeter (DSC) instrument is described, which utilizes autosampling for continuous operation. High scanning rates to 250 deg/h with rapid cooling and equilibration between scans facilitates higher sample throughput up to 50 samples during each 24 h of unattended operation. The instrument is suited for those pharmaceutical applications where higher throughput is important, such as screening drug candidates for binding constant or screening solution conditions for stability of liquid protein formulations. Results are presented on the binding of five different anionic inhibitors to ribonuclease A, which included cytidine 2'-monophosphate (2'CMP), 3'CMP, uridine 3'-monophosphate, pyrophosphate, and phosphate. Binding constants K(B) (or dissociation constants K(d)) are obtained from the shift in the transition temperature T(M) for ribonuclease thermal unfolding in the presence of ligand relative to the transition temperature in the absence of ligand. Measured binding constants ranged from 155 M(-1) (K(d) = 6.45 mM) for the weak-binding phosphate anion to 13100 M(-1) (K(d) = 76.3 microM) for the strongest binding ligand, 2'CMP. The DSC method for measuring binding constants can also be extended to ultratight interactions involving either ligand-protein or protein-protein binding.

Views of chartered physiotherapists on the psychological content of their practice: a preliminary study in the United Kingdom

Abstract: Background: Although research into the psychological aspects of sports injury is increasing and psychological interventions have been identified as important in the rehabilitation process, few studies have focused on how sports medicine practitioners deal with psychological problems. Objective: To investigate the perceptions of English chartered physiotherapists on the psychological content of their practice. Methods: The Physiotherapist and Sport Psychology Questionnaire (PSPQ) was adapted slightly from the Athletic Trainer and Sport Psychology Questionnaire and used in this study. A survey package comprising a PSPQ, introductory letter, and self addressed envelope was mailed to 179 chartered physiotherapists registered in the England Eastern Region Sports Medicine Directory. Results: In total, 90 (50% response rate) questionnaires were returned. The sample consisted of 67 women and 23 men with a mean (SD) age of 40.1 (5.4) years and 9.2 (3.1) years of experience as chartered physiotherapists. Descriptive statistical and qualitative analysis showed that physiotherapists believed athletes were often psychologically affected by injury. The physiotherapists also reported often using psychological techniques when treating injured athletes, but few reported having access to a sport psychologist for referral. Conclusions: This research indicates that future physiotherapy education may need more emphasis on the psychological aspect of injury, and seek to increase knowledge on the potential of using psychological interventions within a physiotherapy rehabilitation programme. Furthermore, some form of referral network should be established between chartered physiotherapists and sport psychologists.

On the compatibility between defuzzification and fuzzy arithmetic operations

Abstract: Since the introduction of the extension principle by Zadeh, the arithmetic of fuzzy numbers has gained importance both from the theoretical and the practical points of view. For the former, many works were accomplished on the topological level as well as on the parametrization level in order to improve the foundation of the theory and to simplify the performance of different combination operations. For the latter, in many practical applications, the need for a permanent switch from a fuzzy representation to a numerical representation is patent. This transformation is usually carried out by the defuzzification process. This paper addresses some theoretical results about some invariance properties concerning the relationships between the defuzzification outcomes and the arithmetic of fuzzy numbers. One of the benefits of such analysis is the fact that when the matter is the determination of the defuzzified value pertaining to the result of some manipulation of fuzzy quantities, the explicit determination of the resulting fuzzy set (or distribution) can be obviated, while the process may be restricted to a standard computation over single values corresponding to defuzzified initial inputs.

Methods for Rearing the Asian Longhorned Beetle (Coleoptera: Cerambycidae) on Artificial Diet

Abstract: The Asian longhorned beetle, Anoplophora glabripennis (Motschulsky), was recently introduced to the United States and has the potential to destroy many urban and forest trees. A successful artificial diet and rearing protocol are urgently needed, because research with this wood-boring beetle can be conducted only in the confined areas of quarantines. We compared larval growth and adult parameters using three artificial diets, one developed in China for A. glabripennis and two developed for other members of the Lamiini. The only difference in performance of larvae and adults reared on the three diet types was that nondiapausing larvae reared on Monochamus carolinensis (Olivier) diet needed less time to pupate than nondiapausing larvae on A. glabripennis diet. We further evaluated substituting the phloem–cambium of sugar maple, Acer saccharum Marshall, with sawdust or cellulose. Males grew fastest on diets with sawdust or phloem–cambium and remained as pupae for the shortest period of time on A. glabripennis diet. Females grew faster on diets with cellulose than sawdust and lived longest on A. glabripennis diet. The published A. glabripennis artificial diet, modified by increasing the water content from 50.0 to 64.6% (wt:wt) and substituting the phloem–cambium component with cellulose, was the optimal diet tested. A rearing protocol used to maintain our colony is included.

Family therapy and dialectical behavior therapy with adolescents: Part I: Proposing a clinical synthesis

Abstract: Although the practice of family therapy in dialectical behavior therapy (DBT) with multiproblem suicidal adolescents is common and generally indicated, a particular model has yet to be delineated with this age group. The purpose of this article is to propose a coherent clinical synthesis of the more individually oriented DBT strategies with a broader family-systems orientation that maintains the integrity of both theoretical approaches while addressing the treatment needs of adolescents and their families. First, the authors briefly review the literature. Second, they describe the core dialectic of DBT, balancing acceptance and change, and its relevance to family therapy. Finally, the authors propose several specific acceptance and change strategies useful when implementing DBT family therapy with multi-problem adolescents.

Revision: is visual perception a requisite for visual imagery?

Abstract: Vision is the most highly developed sense in man and represents the doorway through which most of our knowledge of the external world arises. Visual imagery can be defined as the representation of perceptual information in the absence of visual input. Visual imagery has been shown to complement vision in this acquisition of knowledge—it is used in memory retrieval, problem solving, and the recognition of properties of objects. The processes underlying visual imagery have been assimilated to those of the visual system and are believed to share a neural substrate. However, results from studies in congenitally and cortically blind subjects have opposed this hypothesis. Here I review the currently available evidence.

The “Belbin” team role inventory: reinterpreting reliability estimates

Abstract: Previous research into the reliability of the “Belbin” team role self‐perception inventory has concluded that internal consistency reliability is poor, raising concerns about the validity of the inventory as a selection and development tool This paper argues that, in overcoming the problem of unequal scale lengths between respondents, researchers have tampered with the true error variance contained within item response sets, leading to a misapplication of Cronbach’s alpha in this case Using weighted average inter‐item correlation coefficients in a formula unrelated to scale length, alternative estimates of the internal consistency reliability of the TRSPI’s scales are derived For a large data set (n=5,003), results show that the internal consistency of item responses is better than previous research suggests and tends towards the boundary at which internal consistency is considered acceptable in social and psychological research

Analysis of the relationship between nurse influences over flexible working and commitment to nursing

Abstract: Background. The paper explores the theoretical and practical bases of both commitment and control within the context of temporal aspects of flexible working in nursing. Aim. The aims of the paper are to examine the relationships between nurses' shift patterns, influence over shift pattern and realization of shift preference and commitment to nursing. Methods. Data were collected through a postal questionnaire completed by 2987 British nurses employed in hospitals, care homes and hospices. Principal components analysis was used to identify common factors among responses to a series of 33 statements about working life. Data were analysed using ANOVA and multiple regression techniques. Results. Permanent night shift nurses reported lower levels of commitment to nursing. As predicted, influence over shift patterns and realization of preferred shift pattern were positively associated with commitment to nursing, although the relationship was weak. Positive perceptions of career development opportunities were a stronger predictor of commitment to nursing. Results are discussed in light of previous ethnographic research on nurses' shift patterns. Conclusion. The opportunity to explore quantitatively the effects of shift-related decisions on commitment using a large sample is useful. While influence and shift type were predictors of commitment, the positive impact they were expected to have was smaller than expected. Similarly, the negative effects of not having influence or of working permanent night shifts were smaller than expected and the statistical significance of such small effects relies heavily on the large sample obtained. Other variables, particularly career development prospects, outweigh the influence of shift-related variables on commitment. The research gives a clear message to human resource managers involved with nurse management: so long as nurses have a strong perception of career development potential the otherwise negative influences of shift impact can be minimized.

Focusing on focus groups: lessons from a research project involving a Bangladeshi community:

Abstract: This article examines the main issues and challenges associated with the use of the focus group method in a research study involving small business and entrepreneurship. The project concerned the education and training needs of a Bangladeshi community in a West Midlands city, commissioned by the local Chamber of Commerce Training and Enterprise. The article considers the advice provided in the literature on the conduct of focus groups, describes the application of that advice to gather empirical data from an ethnic community, and discusses the insights gained from the use of focus groups in these circumstances. Both the positive and negative features of the research process and outcomes are covered, and the impact of the focus group method on the successes and failures of the project is discussed.

Plausible and adaptive requirement traceability structures

Abstract: This paper presents an extension of a traceability system which automates the generation of traceability relations between textual requirement artefacts and object models using heuristic traceability rules. These rules match syntactically related terms in the textual parts of the requirements artefacts with related elements in an object model (e.g. classes, attributes, operations) and create traceability relations of different types when a match is found. The extension described in this paper measures beliefs in: (1) the ability of specific traceability rules to generate correct traceability relations, (2) the satisfiability of traceability rules by particular types of artefacts, and (3) the correctness of individual traceability relations. It also provides a mechanism with well-founded semantics for revising these beliefs on the basis of partial (and even conflicting) assessments of the relations that these rules generate provided by different users.