27 resultados para self-control

em Aston University Research Archive


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The wearing of tinted spectacle lenses is considered by some health care workers to be a marker of psychopathology or a hypochondriacal personality type. The purpose of this study was to determine whether there is a relationship between the wearing of tinted spectacle lenses and personality type in physically healthy subjects. The Sixteen Personality Factor Questionnaire 5th Edition, a multidimensional standardized self-report inventory, was used to determine the personality type of 98 participants. Twenty currently wore tinted spectacle lenses for reasons other than ocular disease, sun protection, outdoor or indoor glare reduction, pattern sensitive epilepsy, migraines, reading difficulties or fashion. The remainder did not wear tinted spectacle lenses for any purpose other than sun protection. Tinted lens wear and no tinted lens wear groups were age and gender matched. There was no statistically significant difference in five global personality factors between the no-tint and tint groups: extraversion (p = 0.31), anxiety (p = 0.75), tough-mindedness (p = 0.96), independence (p = 0.63), and self-control (p = 0.87). This suggests that the use of tinted lenses by physically healthy people is unlikely to be an indicator of personality type. © 2007 The Author.

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This thesis reports a cross-national study carried out in England and India in an attempt to clarify the association of certain cultural and non-cultural characteristics with people's work-related attitudes and values, and with the structure of their work organizations. Three perspectives are considered to be relevant to the objectives of the study. The contingency perspective suggests that a 'fit' between an organization's context and its structural arrangements will be fundamentally necessary for achieving success and survival. The political economy perspective argues for the determining role of the social and economic structures within which the organization operates. The culturalist perspective looks to cultural attitudes and values of organizational members for an explanation for their organization's structure. The empirical investigation was carried out in three stages in each of the two countries involved by means of surveys of cultural attitudes, work-related attitudes and organizational structures and systems. The cultural surveys suggested that Indian and English people were different from one another with regard to fear of, and respect and obedience to, their seniors, ability to cope with ambiguity, honesty, independence, expression of emotions, fatalism, reserve, and care for others; they were similar with regard to tolerance, friendliness, attitude to change, attitude to law, self-control and self-confidence, and attitude to social differentiation. The second stage of the study, involving the employees of fourteen organizations, found that the English ones perceived themselves to have more power at work, expressed more tolerance for ambiguity, and had different expectations from their job than did the Indian equivalents. The two samples were similar with respect to commitment to their company and trust in their colleagues. The findings also suggested that employees' occupations, education and age had some influences on their work-related attitudes. The final stage of the research was a study of structures, control systems, and reward and punishment policies of the same fourteen organizations which were matched almost completely on their contextual factors across the two countries. English and Indian organizations were found to be similar in terms of centralization, specialization, chief executive's span of control, height and management control strategies. English organizations, however, were far more formalized, spent more time on consultation and their managers delegated authority lower down the hierarchy than Indian organizations. The major finding of the study was the multiple association that cultural, national and contingency factors had with the structural characteristics of the organizations and with the work-related attitudes of their members. On the basis of this finding, a multi-perspective model for understanding organizational structures and systems is proposed in which the contributions made by contingency, political economy and cultural perspectives are recognized and incorporated.

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Past studies resulted in conflicting definitions of consumer motivation. On the one hand, motivations are seen as the consumer’s characteristics that shape her general behavior (motivational trait). On the other hand, they are seen as contextual variables representing the reason why the individual is behaving specific to today’s context (motivational state). The objective of this research is to stress the difference between these two concepts and to understand the impact of each on consumer behavior. We applied our empirical study to shopping motivations; our results show a strong interaction between motivational trait and motivational state. Problem and Hypothesis On the one hand, Westbrook and Black (1985) consider shopping motivations as individual permanent characteristics. This concept is shared by other researchers (Rohm and Swaminathan 2004), which show that some shoppers are functional (they shop for convenience, information seeking, and time saving) while some others are hedonic (they shop for social interaction, bargain hunting and browsing). On the other hand, Kaltcheva and Weitz (2006) define motivations as a contextual orientation changing over time, depending on the situation, and show that contextual shopping motivations have a strong impact on shopping behavior. From our knowledge, no research specifically examined the respective impact of both these shopping motivation types. To deal with this issue, we used the notions of “traits” and “states” that have been largely used in marketing research to designate respectively a permanent characteristic of the individual and a temporary orientation of the consumer (Mowen 2000). The reversal theory (Apter 2001) suggests that two opposite states exist: the telic and the paratelic states. In the telic state, individuals set goals for themselves, must be disciplined to reach these goals, and do not behave in accordance with their personal trait. In the paratelic state, individuals are seeking arousal and enjoyment, do not set rules, and one could postulate that they act in accordance with their natural tendencies. Based on these considerations, we hypothesize the following process: in situations involving paratelic states, hedonic as well as functional individuals should behave according to their natural traits, whereas in situations involving telic states, hedonic people should inhibit their natural propensity to enjoy shopping and behave similarly to functional people. Hence, we postulate the following: Hypothesis: Compared to shoppers with functional motivational trait, shoppers with hedonic motivational trait will a) significantly display more hedonic shopping behavior intentions in a condition of paratelic motivational state, and b) not display more hedonic shopping behavior intentions in a condition a telic motivational state Empirical Research First, 108 participants were asked to fill a multi-items scale about their shopping habits, which actually measured their shopping motivational traits. This questionnaire allowed us to highlight four different dimensions in shopping motivational traits: social interaction, novelty/utility seeking, bargain hunting, and browsing. According to their scores on different items, participants were classified as functional or as hedonic on each of these four dimensions (a single individual may be hedonic on some dimensions and functional on others). Then, participants were then induced to adopt either a telic or a paratelic shopping motivational state while reading an appropriate scenario. Finally, participants were asked for their shopping behavior intentions in response to the shopping context. Four items were developed, corresponding to the four shopping motivational trait dimensions we found with our factor analysis. Results As we found four dimensions in shopping motivational trait, we set up four quasi-experimental designs to capture the entire phenomenon: for each dimension, a 2 (motivational trait) x 2 (motivational state) design was built, where the dependant variable was the shopping behavior element corresponding to the studied dimension. Four 2 x 2 Anovas were performed to assess the interaction between motivational trait and motivational state. Concerning the three dimensions - browsing, novelty/utility seeking, and bargain hunting- , in the paratelic state scenario participants with hedonic motivational trait displayed significantly more hedonic shopping behavior intentions than participants with a functional motivational trait (resp. F = 9.701, p = .003; F = 4.979, p = .03; F = 5.757, p = .02); and in the telic state scenario, there was no significant difference in behavior intentions between participants with hedonic or functional motivation trait. Each time, the interaction effect between motivational state and motivational trait was significant (resp. F = 4.859, p = .03; F = 3.314, p = .07; F = 2.98, p = .08). Concerning the fourth dimension, social interaction, shopping behavior intentions of participants with hedonic and with functional motivational traits were significantly different in the paratelic state scenario (F = 29.898, p <.000) as well as in the telic state scenario (F = 9.559, p = .003). However, the interaction effect showed that this behavioral difference was significantly stronger in the paratelic scenario. All these results support our research hypothesis. Discussion and Implications Our study provides consistent support for our hypotheses saying that there is an interaction effect between shopping motivational states and shopping motivational traits. The generalization of the results is strengthened by the study of four different shopping traits: social interaction, novelty/utility seeking, bargain hunting and browsing. As we proposed, when shopping in a goal-oriented state (telic state), behaviors of hedonic and functional shoppers do not differ significantly. Conversely, when shopping for a recreational reason (paratelic state), hedonic and functional shoppers behave significantly different. These results could explain why some previous studies concluded that shopping motivational traits had no impact on shopping behavior: they did not take into consideration the interaction between motivational trait and motivational state. Moreover, our study shows that marketing surveys performed by store managers to draw the personal profile of their customers must be crossed with contextual motivations in order to accurately forecast shopper behavior. Future Developments Our results can be explained by the self-control process, which pushes hedonic-trait shoppers to behave in a rather functional way in utilitarian situations. However, to be certain that this is the very process that occurs, we plan to add self-control perception scales to our existing measures. This is obviously the next step of this research.

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Full editorial: A recent study evaluating the long-term (2 yr) weight reducing efficacy of different types of diets – high or low in carbohydrates (CHOs), protein or fat - confirmed that it is calorie deficit not dietary composition that determines the loss and maintenance of body weight.1 Is there any advantage in following a specific weight loss diet? Short-term use of nutritionally complete commercially available (very) low calorie diets has benefited people with diabetes when  supported by education programmes.2 Initial weight loss has been encouraging with some fad diets eg the Atkins and the South Beach diets, but these diets are difficult to maintain and there are safety issues regarding their short- and long-term use – especially in people with diabetes.3 The types of macronutrients consumed can have a considerable impact on glycaemic control and energy metabolism. Although a low CHO diet additionally enhances initial weight loss by reducing cellular water content, if fat is not proportionally reduced the diet may not benefit the lipid profile for vascular disease risk. High fat and high protein diets – which are simultaneously low in CHOs – increase vulnerability to hypoglycaemia in people taking insulin secretagogues or on insulin therapy, and may promote excess fat metabolism and ketogenesis, particularly in people vulnerable to lack of insulin. Very low protein diets are not recommended as lean body mass tends to be reduced in diabetes. Altering the macronutrient balance has implications for the micronutrient mix: deficiencies are higher if more foods are excluded and conversely specific micronutrient excess can occur with some fad diets. The altered nutrient mix affects intestinal fauna and flora, and gut motility and glycaemic control are influenced by the quantity and type of fibre consumed. Support programmes help individuals achieve long term weight loss and there is mounting evidence that community schemes which educate and promote lifestyle changes may stem the rising tide of obesity and consequent type 2 diabetes.4 Consuming smaller portions of a balanced diet (and adjusting antidiabetic medications accordingly) will create an energy deficit to promote healthy weight loss. Increased movement/exercise will enhance this energy deficit. Knowledge (eg 1g fat has 2.25 times more energy than 1g CHO) allows sensible food choices and compensation for inclusion of small volumes of  ‘naughty but nice’ foods. Ultimately weight control requires self control. References 1. Sacks FM, Bray GA, Carey VJ et al. Comparison of weight-loss diets with different compositions of fat, protein, and carbohydrates. N Engl J Med 2009;360:859–73. 2. Bennett P. Obesity, diabetes and VLCD. Br J Diabetes Vasc Dis 2004;4:328–30. 3. Baldwin EJ. Fad diets in diabetes. Br J Diabetes Vasc DIs 2004;4:333–7. 4. Romon M, Lommoz A, Tafflet M et al. Downward trends in the prevalence of childhood overweight in the setting of 12-year school- and community-based programmes. Public Health Nutr 2008; Dec 28, 1–8 [Epub ahead of print].

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The main theme of research of this project concerns the study of neutral networks to control uncertain and non-linear control systems. This involves the control of continuous time, discrete time, hybrid and stochastic systems with input, state or output constraints by ensuring good performances. A great part of this project is devoted to the opening of frontiers between several mathematical and engineering approaches in order to tackle complex but very common non-linear control problems. The objectives are: 1. Design and develop procedures for neutral network enhanced self-tuning adaptive non-linear control systems; 2. To design, as a general procedure, neural network generalised minimum variance self-tuning controller for non-linear dynamic plants (Integration of neural network mapping with generalised minimum variance self-tuning controller strategies); 3. To develop a software package to evaluate control system performances using Matlab, Simulink and Neural Network toolbox. An adaptive control algorithm utilising a recurrent network as a model of a partial unknown non-linear plant with unmeasurable state is proposed. Appropriately, it appears that structured recurrent neural networks can provide conveniently parameterised dynamic models for many non-linear systems for use in adaptive control. Properties of static neural networks, which enabled successful design of stable adaptive control in the state feedback case, are also identified. A survey of the existing results is presented which puts them in a systematic framework showing their relation to classical self-tuning adaptive control application of neural control to a SISO/MIMO control. Simulation results demonstrate that the self-tuning design methods may be practically applicable to a reasonably large class of unknown linear and non-linear dynamic control systems.

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Belief-desire reasoning is a core component of 'Theory of Mind' (ToM), which can be used to explain and predict the behaviour of agents. Neuroimaging studies reliably identify a network of brain regions comprising a 'standard' network for ToM, including temporoparietal junction and medial prefrontal cortex. Whilst considerable experimental evidence suggests that executive control (EC) may support a functioning ToM, co-ordination of neural systems for ToM and EC is poorly understood. We report here use of a novel task in which psychologically relevant ToM parameters (true versus false belief; approach versus avoidance desire) were manipulated orthogonally. The valence of these parameters not only modulated brain activity in the 'standard' ToM network but also in EC regions. Varying the valence of both beliefs and desires recruits anterior cingulate cortex, suggesting a shared inhibitory component associated with negatively valenced mental state concepts. Varying the valence of beliefs additionally draws on ventrolateral prefrontal cortex, reflecting the need to inhibit self perspective. These data provide the first evidence that separate functional and neural systems for EC may be recruited in the service of different aspects of ToM.

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FRET (fluorescence resonance energy transfer) and co-immunoprecipitation studies confirmed the capacity of beta-arrestin 2 to self-associate. Amino acids potentially involved in direct protein-protein interaction were identified via combinations of spot-immobilized peptide arrays and mapping of surface exposure. Among potential key amino acids, Lys(285), Arg(286) and Lys(295) are part of a continuous surface epitope located in the polar core between the N- and C-terminal domains. Introduction of K285A/R286A mutations into beta-arrestin 2-eCFP (where eCFP is enhanced cyan fluorescent protein) and beta-arrestin 2-eYFP (where eYFP is enhanced yellow fluorescent protein) constructs substantially reduced FRET, whereas introduction of a K295A mutation had a more limited effect. Neither of these mutants was able to promote beta2-adrenoceptor-mediated phosphorylation of the ERK1/2 (extracellular-signal-regulated kinase 1/2) MAPKs (mitogen-activated protein kinases). Both beta-arrestin 2 mutants displayed limited capacity to co-immunoprecipitate ERK1/2 and further spot-immobilized peptide arrays indicated each of Lys(285), Arg(286) and particularly Lys(295) to be important for this interaction. Direct interactions between beta-arrestin 2 and the beta2-adrenoceptor were also compromised by both K285A/R286A and K295A mutations of beta-arrestin 2. These were not non-specific effects linked to improper folding of beta-arrestin 2 as limited proteolysis was unable to distinguish the K285A/R286A or K295A mutants from wild-type beta-arrestin 2, and the interaction of beta-arrestin 2 with JNK3 (c-Jun N-terminal kinase 3) was unaffected by the K285A/R286A or L295A mutations. These results suggest that amino acids important for self-association of beta-arrestin 2 also play an important role in the interaction with both the beta2-adrenoceptor and the ERK1/2 MAPKs. Regulation of beta-arrestin 2 self-association may therefore control beta-arrestin 2-mediated beta2-adrenoceptor-ERK1/2 MAPK signalling.

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Advances in technology coupled with increasing labour costs have caused service firms to explore self-service delivery options. Although some studies have focused on self-service and use of technology in service delivery, few have explored the role of service quality in consumer evaluation of technology-based self-service options. By integrating and extending the self-service quality framework the service evaluation model and the Technology Acceptance Model the authors address this emerging issue by empirically testing a comprehensive model that captures the antecedents and consequences of perceived service quality to predict continued customer interaction in the technology-based self-service context of Internet banking. Important service evaluation constructs like perceived risk, perceived value and perceived satisfaction are modelled in this framework. The results show that perceived control has the strongest influence on service quality evaluations. Perceived speed of delivery, reliability and enjoyment also have a significant impact on service quality perceptions. The study also found that even though perceived service quality, perceived risk and satisfaction are important predictors of continued interaction, perceived customer value plays a pivotal role in influencing continued interaction.

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Aim: To measure the relationship between perceived child competence, parental self-efficacy, and children's glycaemic control. Methods: Cross-sectional outpatient based questionnaire survey of 78 parents of children aged 6-12 years with insulin dependent diabetes mellitus, diagnosed for at least one year. Parental perceptions of their child's competence were assessed, together with parental perceptions of their own self-efficacy in managing their child's diabetes. Glycaemic control was assessed by the average annual HbA 1C level. Results: The response rate was 64.5% (51 parents); 82% were mothers and the socioeconomic class and ethnicity spread was representative of the general population. The mean age of the children was 10 years and duration of diabetes 4.4 years. Poorer glycaemic control was associated with higher perceived child competence, together with lower perceived age of responsibility, lower perceived seriousness, and less frequent blood tests. Higher parental self-efficacy and higher perceived child competence predicted a higher level of normalisation, as did lower perceived seriousness, a lower perceived parental responsibility for management, and a less protective style of parenting. Conclusion: Parents' perceptions of their children's diabetes are significantly related to glycaemic control; however, those who appear more competent at managing diabetes may overestimate their child's capabilities, leading to poorer glycaemic control.

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Background: Self-monitoring of blood glucose is controversial in the management of type 2 diabetes. Some research suggests that self-monitoring improves glycaemic control, whereas other research is sceptical about its value for people with type 2 diabetes who are not on insulin. Although blood glucose meters are widely available and used by this group, patients' own views are absent from the debate. Aim: To explore the pros and cons of glucose monitoring from the patients' perspectives. Design of study: Qualitative repeat-interview study. Setting: Patients were recruited from 16 general practices and three hospital clinics within four local healthcare cooperatives in Lothian, Scotland. Method: Interview data from 40 patients diagnosed with type 2 diabetes within the previous 6 months were analysed using thematic analysis informed by grounded theory. We report findings from round 1 and round 2 interviews. Results: Glucose monitoring can heighten patients' awareness of the impact of lifestyle; for example, dietary choices, on blood glucose levels. Glucose monitoring amplifies a sense of 'success' or 'failure' about self-management, often resulting in anxiety and self-blame if glucose readings remain consistently high. Moreover, monitoring can negatively effect patients' self-management when readings are counter-intuitive. Conclusion: Our analysis highlights the importance of understanding the meanings that newly diagnosed patients attach to glucose self-monitoring. To maximise the positive effects of self-monitoring, health professionals should ensure that patients understand the purpose of monitoring and should clarify with patients how readings should be interpreted. © British Journal of General Practice.

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The question of how to develop leaders so that they are more effective in a variety of situations, roles and levels has inspired a voluminous amount of research. While leader development programs such as executive coaching and 360-degree feedback have been widely practiced to meet this demand within organisations, the research in this area has only scratched the surface. Drawing from the past literature and leadership practices, the current research conceptualised self-regulation, as a metacompetency that would assist leaders to further develop the specific competencies needed to perform effectively in their leadership role, leading to an increased rating of leader effectiveness and to enhanced group performance. To test this conceptualisation, a longitudinal field experimental study was conducted across ten months with a pre- and two post-test intervention designs with a matched control group. This longitudinal field experimental compared the difference in leader and team performance after receiving self-regulation intervention that was delivered by an executive coach. Leaders in experimental group also received feedback reports from 360-degree feedback at each stage. Participants were 40 leaders, 155 followers and 8 supervisors. Leaders’ performance was measured using a multi-source perceptual measure of leader performance and objective measures of team financial and assessment performance. Analyses using repeated measure of ANCOVA on pre-test and two post-tests responses showed a significant difference between leader and team performance between experimental and control group. Furthermore, leader competencies mediated the relationship between self-regulation and performance. The implications of these findings for the theory and practice of leadership development training programs and the impact on organisational performance are discussed.

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Magnetic levitation bearings eliminate friction, wear and the need for lubrication and so have high speed capability and potential for vibration control. One noteworthy development in the realm of magnetic levitation is the self-bearing or bearingless motor - an electromagnetic machine that supports its own rotor by way of magnetic forces generated by windings on its stator. Accordingly, various winding schemes have been proposed to accomplish the task of force production. This thesis proposes a novel concept of winding based on a bridge connection for polyphase self-bearing rotating electrical machines with the following advantages: • the connection uses a single set of windings and thus power loss is relatively low when compared with self-bearing motors with conventional dual set of windings. • the motor and levitation controls are segregated such that only one motor inverter is required for the normal torque production and levitation forces are produced by using auxiliary power supplies of relatively low current and voltage rating. The usual way of controlling the motor is retained. • there are many variant winding schemes to meet special needs. • independent power supplies for levitation control offer redundancy for fault tolerance. This thesis dwells specifically on the conceptual design and implementation of the proposed single set of windings scheme. The new connection has been verified to exhibit characteristics of a self-bearing motor via coupled-field finite element analysis: results are crosschecked analytically. Power loss and other aspects such as cost, design implementation are compared to support the newly proposed connection as a potential alternative to present designs.

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OBJECTIVES: To assess whether blood pressure control in primary care could be improved with the use of patient held targets and self monitoring in a practice setting, and to assess the impact of these on health behaviours, anxiety, prescribed antihypertensive drugs, patients' preferences, and costs. DESIGN: Randomised controlled trial. SETTING: Eight general practices in south Birmingham. PARTICIPANTS: 441 people receiving treatment in primary care for hypertension but not controlled below the target of < 140/85 mm Hg. INTERVENTIONS: Patients in the intervention group received treatment targets along with facilities to measure their own blood pressure at their general practice; they were also asked to visit their general practitioner or practice nurse if their blood pressure was repeatedly above the target level. Patients in the control group received usual care (blood pressure monitoring by their practice). MAIN OUTCOME MEASURES: Primary outcome: change in systolic blood pressure at six months and one year in both intervention and control groups. Secondary outcomes: change in health behaviours, anxiety, prescribed antihypertensive drugs, patients' preferences of method of blood pressure monitoring, and costs. RESULTS: 400 (91%) patients attended follow up at one year. Systolic blood pressure in the intervention group had significantly reduced after six months (mean difference 4.3 mm Hg (95% confidence interval 0.8 mm Hg to 7.9 mm Hg)) but not after one year (mean difference 2.7 mm Hg (- 1.2 mm Hg to 6.6 mm Hg)). No overall difference was found in diastolic blood pressure, anxiety, health behaviours, or number of prescribed drugs. Patients who self monitored lost more weight than controls (as evidenced by a drop in body mass index), rated self monitoring above monitoring by a doctor or nurse, and consulted less often. Overall, self monitoring did not cost significantly more than usual care (251 pounds sterling (437 dollars; 364 euros) (95% confidence interval 233 pounds sterling to 275 pounds sterling) versus 240 pounds sterling (217 pounds sterling to 263 pounds sterling). CONCLUSIONS: Practice based self monitoring resulted in small but significant improvements of blood pressure at six months, which were not sustained after a year. Self monitoring was well received by patients, anxiety did not increase, and there was no appreciable additional cost. Practice based self monitoring is feasible and results in blood pressure control that is similar to that in usual care.

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Aims To date, there is no convincing evidence that non-insulin treated patients who undertake self-blood glucose monitoring (SBGM) have better glycaemic control than those who test their urine. This has led to a recommendation that non-insulin dependent patients undertake urine testing, which is the cheaper option. This recommendation does not take account of patients' experiences and views. This study explores the respective merits of urine testing and SBGM from the perspectives of newly diagnosed patients with Type 2 diabetes. Methods Qualitative study using repeat in-depth interviews with 40 patients. Patients were interviewed three times at 6-monthly intervals over 1 year. Patients were recruited from hospital clinics and general practices in Lothian, Scotland. The study was informed by grounded theory, which involves concurrent data collection and analysis. Results Patients reported strongly negative views of urine testing, particularly when they compared it with SBGM. Patients perceived urine testing as less convenient, less hygienic and less accurate than SBGM. Most patients assumed that blood glucose meters were given to those with a more advanced or serious form of diabetes. This could have implications for how they thought about their own disease. Patients often interpreted negative urine results as indicating that they could not have diabetes. Conclusions Professionals should be aware of the meanings and understandings patients attach to the receipt and use of different types of self-monitoring equipment. Guidelines that promote the use of consistent criteria for equipment allocation are required. The manner in which negative urine results are conveyed needs to be reconsidered.

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The behaviour of control functions in safety critical software systems is typically bounded to prevent the occurrence of known system level hazards. These bounds are typically derived through safety analyses and can be implemented through the use of necessary design features. However, the unpredictability of real world problems can result in changes in the operating context that may invalidate the behavioural bounds themselves, for example, unexpected hazardous operating contexts as a result of failures or degradation. For highly complex problems it may be infeasible to determine the precise desired behavioural bounds of a function that addresses or minimises risk for hazardous operation cases prior to deployment. This paper presents an overview of the safety challenges associated with such a problem and how such problems might be addressed. A self-management framework is proposed that performs on-line risk management. The features of the framework are shown in context of employing intelligent adaptive controllers operating within complex and highly dynamic problem domains such as Gas-Turbine Aero Engine control. Safety assurance arguments enabled by the framework necessary for certification are also outlined.