Showing papers by "Newcastle University published in 1992"
TL;DR: In this article, the authors argue that the analysis of intangible resources should play a major role in the strategic management process, by means of both theoretical reasoning and empirical evidence, and argue that sustainable competitive advantage results from the possession of relevant capability differentials.
Abstract: Sustainable competitive advantage results from the possession of relevant capability differentials. The feedstock of these capability differentials is intangible resources which range from patents and licenses, to reputation and know-how. A framework of intangible resources has been produced which formed the basis for a national survey of chief executives in the U.K. Some of the more significant findings of the survey were that: employee know-how and reputation are perceived as the resources which make the most important contribution to business success; and that for most companies operations is the most important area of employee know how. This article argues, by means of both theoretical reasoning and empirical evidence, that the analysis of intangible resources should play a major role in the strategic management process.
2,625 citations
942 citations
TL;DR: This work has suggested that interviews with new mothers who delivered their babies at home in a hypothetical controlled trial of home versus hospital confinement would provide fascinating accounts of the pleasure of successful delivery at home, but by definition the interviews would exclude the hazard and drama of necessary transfers to hospital due to complications in late pregnancy and early labour.
Abstract: Intention-to-treat analysis is an important aspect of randomized controlled trials of health care interventions. The concept is now widely accepted in theory, but not always implemented in practice. Failure to analyse by intention-to-treat can give misleading and indeed life-threatening interpretations. In some studies, a case is put for estimating the effect that would have been observed if all patients had received the allocated treatment. Situations where this is valid are rare, but an example is given of such an exceptional study. The relevance of the intention-to-treat concept is not always taken into account in qualitative research. Interviews with new mothers who delivered their babies at home in a hypothetical controlled trial of home versus hospital confinement would provide fascinating accounts of the pleasure of successful delivery at home. But by definition the interviews would exclude the hazard and drama of necessary transfers to hospital due to complications in late pregnancy and early labour. The intention-to-treat approach would avoid this bias.
580 citations
TL;DR: In this article, a robust H/sub infinity / control design for linear systems with uncertainty in both the state and input matrices is treated, and a state feedback control design which stabilizes the plant and guarantees an H/ sub infinity /-norm bound constraint on disturbance attenuation for all admissible uncertainties is presented.
Abstract: Robust H/sub infinity / control design for linear systems with uncertainty in both the state and input matrices is treated. A state feedback control design which stabilizes the plant and guarantees an H/sub infinity /-norm bound constraint on disturbance attenuation for all admissible uncertainties is presented. The robust H/sub infinity / control problem is solved via the notion of quadratic stabilization with an H/sub infinity /-norm bound. Necessary and sufficient conditions for quadratic stabilization with an H/sub infinity /-norm bound are derived. The results can be regarded as extensions of existing results on H/sub infinity / control and robust stabilization of uncertain linear systems. >
540 citations
TL;DR: In this paper, the robust H/sub infinity / control problem of designing a linear dynamic output feedback controller such that the closed-loop system is quadratically stable and achieves a prescribed level of disturbance attenuation for all admissible parameter uncertainties is considered.
Abstract: The article concerns linear systems which are subject to both time-varying norm-bounded parameter uncertainty and exogenous disturbance It addresses the robust H/sub infinity / control problem of designing a linear dynamic output feedback controller such that the closed-loop system is quadratically stable and achieves a prescribed level of disturbance attenuation for all admissible parameter uncertainties It is shown that such a problem is equivalent to a scaled H/sub infinity / control problem >
534 citations
TL;DR: In this article, a software-controlled hardness tester (Nanoindenter) operating in the load range 2-60 mN was used to characterize the deformation structures associated with these very small-scale hardness impressions.
Abstract: The ultra-low load indentation response of ceramic single crystal surfaces (Al2O3, SiC, Si) has been studied with a software-controlled hardness tester (Nanoindenter) operating in the load range 2–60 mN. In all cases, scanning and transmission electron microscopy have been used to characterize the deformation structures associated with these very small-scale hardness impressions. Emphasis has been placed on correlating the deformation behavior observed for particular indentations with irregularities in recorded load-displacement curves. For carefully annealed sapphire, a threshold load (for a given indenter) was observed below which the only surface response was elastic flexure and beyond which dislocation loop nucleation occurred at, or near, the theoretical shear strength to create the indentation. This onset of plasticity was seen as a sudden displacement discontinuity in the load-displacement response. At higher loads, indentations appeared to be accommodated predominantly by dislocation activity, though microcracks were observed to form at contact loads of only tens of milliNewtons. Possibly such cracks are the incipient slip-induced nuclei for the much larger, indentation-induced cracks usually apparent only on the surface at much higher loads and often used for estimating indentation toughness. By contrast, silicon did not show this behavior but exhibited unusually large amounts of depth recovery within indentations, resulting in a characteristic reverse thrust on the indenter during unloading. TEM studies of indentations in silicon revealed less evidence of obvious dislocation activity than in sapphire (particularly at the lowest loads used) but did show residual highly imperfect–and often amorphous–structures within the indentations, consistent with a densification transformation occurring at the very high hydrostatic stresses produced under the indenter. The reverse thrust is caused by the relaxation of densified material during unloading. Thus, it appears that the low-load hardness response of silicon is controlled by a pressure-sensitive phase transformation. Though SiC has been predicted to undergo a densification transformation similar to silicon, its load-displacement behavior was found to be similar to Al2O3 suggesting that, for these contact experiments at least, the critical resolved shear stress for dislocation nucleation is exceeded before the critical hydrostatic pressure for densification is reached. In all cases, residual, plastically formed indentations were measured to be smaller than the fully loaded indentation depths would suggest, confirming that a significant portion of the deformation is elastic surface flexure. However, there is some doubt as to whether silicon displays elastic-only deformation even at very small penetration depths. The use of microstructural studies to complement nanoindentation experiments is shown to be a key route not only to interpreting the recorded load-displacement responses, but also to examining the deformation mechanisms controlling the mechanical behavior of ceramics to surface contacts at these small spatial scales.
509 citations
TL;DR: The authors explore the connection between social class and social network and suggest the outlines of a model that can integrate them in a coherent way, based on linking a consensus-based microlevel of network with a conflict-based macrolevel of social class.
Abstract: In sociolinguistics, approaches that use the variables of socioeconomic class and social network have often been thought to be irreconcilable. In this article, we explore the connection between these variables and suggest the outlines of a model that can integrate them in a coherent way. This depends on linking a consensus-based microlevel of network with a conflict-based macrolevel of social class. We suggest interpretations of certain sociolinguistic findings, citing detailed evidence from research in Northern Ireland and Philadelphia, which emphasize the need for acknowledging the importance of looseknit network ties in facilitating linguistic innovations. We then propose that the link between network and class can be made via the notion of weak network ties using the process-based model of the macrolevel suggested by Thomas H0jrup's theory of life-modes. (Sociolinguistics, sociology, quantitative social dialectology, anthropological linguistics) One of the most important contributions of Labov's quantitative paradigm has been to allow us to examine systematically and accountably the relationship between language variation and speaker variables such as sex, ethnicity, social network, and - most importantly perhaps - social class. Language variation in large and linguistically heterogeneous cities as well as in smaller communities has been revealed not as chaotic but as socially regular, and Labov and others have shown how investigating this socially patterned variation can illuminate mechanisms of linguistic change. In this article, we focus on the variables of social class and social network, both of which have appeared in some form in a large number sociolinguistic studies of variation and change. Our principal interest lies not in the complex sociological issues associated with class and network, some of which we discuss here, but in understanding the role of class and network in patterns of linguistic variation and mechanisms of linguistic change.
434 citations
TL;DR: Preliminary data is presented that velocardiofacial syndrome patients have similar chromosome deletions, a finding consistent with the hypothesis that these disorders represent part of a spectrum of abnormalities seen with monosomy for 22q11.
392 citations
TL;DR: It is suggested that c-erbB-2 protein overexpression, a marker of poor prognosis in breast cancer, is associated with a lack of response to endocrine therapy on relapse, and particularly in combination with EGFR may be useful in directing therapeutic choices.
Abstract: Of 221 patients with breast cancer of known epidermal growth factor receptor (EGFR) and oestrogen receptor (ER) status, 99 had developed recurrences during the period of follow-up (range 3-60 months, median 24 months). Of these, 72 received endocrine therapy as first-line treatment for relapse. Immunohistochemical assessment of c-erbB-2 protein product expression was made using paraffin-embedded tumour tissue from 65 of these 72 patients. Including patients whose disease remained stable for more than 6 months with those showing an objective response (CR or PR for more than 3 months), only one (7%) of 14 c-erbB-2 positive tumours responded to endocrine manipulation compared with 19 (37%) of 51 c-erbB-2 negative tumours (P less than 0.05). Coexpression of c-erbB-2 reduced the response rate of ER positive patients from 48% to 20% and of ER negative cases from 27% to 0% (P less than 0.01). EGFR and c-erbB-2 protein appeared to have additive effects in reducing the likelihood of response, and none of eight patients with EGFR positive, c-erbB-2 positive tumours derived benefit from endocrine therapy. The results of this study suggest that c-erbB-2 protein overexpression, a marker of poor prognosis in breast cancer, is associated with a lack of response to endocrine therapy on relapse, and particularly in combination with EGFR may be useful in directing therapeutic choices.
392 citations
TL;DR: The paper concludes by showing how the obtained error bounds can be used for intelligent model order selection that takes into account both measurement noise and under-model- ing.
Abstract: Previous results on estimating errors or error bounds on identified transfer functions have relied on prior assumptions about the noise and the unmodeled dynamics. This prior information took the form of parameterized bounding functions or parameterized probability density functions, in the time or frequency domain with known parameters. It is shown that the parameters that quantify this prior information can themselves be estimated from the data using a maximum likelihood technique. This significantly reduces the prior information required to estimate transfer function error bounds. The authors illustrate the usefulness of the method with a number of simulation examples. How the obtained error bounds can be used for intelligent model-order selection that takes into account both measurement noise and under-modeling is shown. Another simulation study compares the method to Akaike's well-known FPE and AIC criteria. >
370 citations
TL;DR: It is demonstrated that neonatal blood glucose concentrations should be considered in the context of availability of other metabolic fuels, and that the preterm infant has a limited ability to mobilise alternative fuels.
Abstract: There have been few comprehensive accounts of the relationships between glucose and other metabolic fuels during the first postnatal week, especially in the context of modern feeding practises. A cross sectional study was performed of 156 term infants and 62 preterm infants to establish the normal ranges and interrelationships of blood glucose and intermediary metabolites in the first postnatal week, and to compare these with those of 52 older children. Blood glucose concentrations varied more for preterm than for term infants (1.5-12.2 mmol/l v 1.5-6.2 mmol/l), and preterm infants had low ketone body concentrations, even at low blood glucose concentrations. Breast feeding of term infants and enteral feeding of preterm infants appeared to enhance ketogenic ability. Term infants had lower prefeed blood glucose concentrations than children but, like children, appeared to be capable of producing ketone bodies. This study demonstrates that neonatal blood glucose concentrations should be considered in the context of availability of other metabolic fuels, and that the preterm infant has a limited ability to mobilise alternative fuels.
TL;DR: The non-pathogenic bacterium Bacillus subtilis, since its first reported genetic transformation in 1959, has become a model system for the study of many aspects of the biochemistry, genetics and physiology of Gram-positive bacteria, and particularly of sporulation and associated metabolism.
TL;DR: A high-performance liquid chromatographic method is described for the separation and quantification of allantoin and oxypurines in plasma and urine samples, indicating a good precision of the method.
01 Feb 1992
TL;DR: An attempt is made to organize and survey recent work, and to present it in a unified and accessible form, on the need for a new approach suitable for high-speed processing and the use of difference operators in numerical analysis.
Abstract: An attempt is made to organize and survey recent work, and to present it in a unified and accessible form. The need for a new approach suitable for high-speed processing is discussed in the context of several applications in control and communications, and a historical perspective of the use of difference operators in numerical analysis is presented. The general systems calculus, based on divided-different operators is introduced to unify the continuous-time and discrete-time systems theories. This calculus is then used as a framework to treat the three problems of system state estimation; system identification and time-series modeling; and control system design. Realization aspects of algorithms based on the difference operator representation, including such issues as coefficient rounding and implementation with standard hardware, are also discussed. >
TL;DR: An 11-kilobase gene region of Streptococcus mutans has been identified which contains eight contiguous genes involved with the uptake and metabolism of multiple sugars (the msm system), and Insertional inactivation of each of these genes along with uptake data indicate that this system is responsible for the uptake of melibiose, raffinose, and isomaltotriose.
TL;DR: In this article, the authors examined the effect of selected countryside characteristics on house prices in a rural area of the United Kingdom centred around the Forest of Dean in Gloucestershire.
TL;DR: The "descending contralateral movement detector" (DCMD) neuron in the locust has been challenged with a variety of moving stimuli, including scenes from a film (Star Wars), moving disks, and images generated by computer, and the neuron responds well to any rapid movement.
Abstract: 1. The "descending contralateral movement detector" (DCMD) neuron in the locust has been challenged with a variety of moving stimuli, including scenes from a film (Star Wars), moving disks, and images generated by computer. The neuron responds well to any rapid movement. For a dark object moving along a straight path at a uniform velocity, the DCMD gives the strongest response when the object travels directly toward the eye, and the weakest when the object travels away from the eye. Instead of expressing selectivity for movements of small rather than large objects, the DCMD responds preferentially to approaching objects. 2. The neuron shows a clear selectivity for approach over recession for a variety of sizes and velocities of movement both of real objects and in simulated movements. When a disk that subtends > or = 5 degrees at the eye approaches the eye, there are two peaks in spike rate: one immediately after the start of movement; and a second that builds up during the approach. When a disk recedes from the eye, there is a single peak in response as the movement starts. There is a good correlation between spike rate and angular acceleration of the edges of the image over the eye. 3. When an object approaches from a distance sufficient for it to subtend less than one interommatidial angle at the start of its approach, there is a single peak in response. The DCMD tracks the approach, and, if the object moves at 1 m/s or faster, the spike rate increases throughout the duration of object movement. The size of the response depends on the speed of approach. 4. It is unlikely that the DCMD encodes the time to collision accurately, because the response depends on the size as well as the velocity of an approaching object. 5. Wide-field movements suppress the response to an approaching object. The suppression varies with the temporal frequency of the background pattern. 6. Over a wide range of contrasts of object against background, the DCMD gives a stronger response to approaching than to receding objects. For low contrasts, the selectivity is greater for objects that are darker than the background than for objects that are lighter.
TL;DR: In this paper, the authors extend the analysis to cover a wider spectrum of degrees and types of altruistic concern than has so far been considered in the literature, and propose a willingness-to-pay approach to the assessment of public-sector projects that have potential safety effects.
Abstract: In applying the willingness-to-pay approach to the assessment of public-sector projects that have potential safety effects, it is clearly important to know whether and how values of statistical life and safety should reflect people's altruistic concern for other people's wellbeing. Thus far this question has been answered only for a very limited number of special cases. The purpose of this paper is to extend the analysis to cover a wider spectrum of degrees and types of altruistic concern than has so far been considered in the literature. Copyright 1992 by Royal Economic Society.
TL;DR: It is argued that research methods are often flawed by using inappropriate measures and greater care is warranted in their selection, where appropriate measures do not exist and only then is the costly process of developing new assessments warranted.
Abstract: Assessing patients’ satisfaction with the care they receive is assuming greater importance and satisfaction with nursing is no exception The kinds of study in which patient satisfaction has been used as an outcome are considered and show the range of conceptualizations and the general lack of rigour in its measurement It is argued that research methods are often flawed by using inappropriate measures and greater care is warranted in their selection Where appropriate measures do not exist, only then is the costly process of developing new assessments warranted Some of the necessary steps in arriving at reliable and valid measures of patient satisfaction are discussed in the context of asking particular research questions
TL;DR: In this article, it has been shown that hydrogen peroxide interferes in chemical oxygen demand (COD) analysis, and further shows how to allow for this interference in future COD analysis.
TL;DR: All patients with hereditary haemorrhagic telangiectasia (HHT) were symptomatic by 40 years of age and 62% by 16 years, and an age of onset curve given.
Abstract: Data from 98 patients with hereditary haemorrhagic telangiectasia (HHT) are presented. All were symptomatic by 40 years of age and 62% by 16 years. Nose bleeding was the first symptom of disease in 90% of cases with mucocutaneous telangiectases appearing 5 to 20 years later. Complications of HHT are discussed and an age of onset curve given.
TL;DR: The suitability of the artificial neural network methodology for solving some process engineering problems is discussed and the technique to provide estimates of difficult to measure quality variables is demonstrated by application to industrial data.
TL;DR: In this article, a series of case studies of transitions from authoritarian to democratic regimes in the Third World is presented, and it is found that the institutions of formal democracy that have recently re-emerged in many countries of the third world have failed to broaden popular political participation in a very meaningful way.
Abstract: By evoking the US counter-insurgency catch phrase 'low intensity conflict', it is out intention to show that perhaps more than at any other time in the recent past, today the struggle to define 'democracy' has become a major ideological battle. 'Democracy' has replaced 'development' as the buzzword for the 1990s. Democracy seems to be sweeping the globe, driving before it both communist party dictatorships and rightist military regimes on every continent. Yet the paradox of this new wave of democratisation is that its 'success' is built upon the failure of 'development' both in the Third World and the former Second World. Some have tried to explain this wave of political change as the historical triumph of an idea/ideal, heralding the dawn of a grand new age of global democracy. Alternatively, there are grounds to be sceptical of both the purported causes, and the ends, of this putative democratic new world order. Whereas some regard formal democracy to be sufficient in itself, if the content of this new democracy is critically examined it may be found to be seriously flawed on many counts. This article began as a book project involving a series of case studies of transitions from authoritarian to democratic regimes in the Third World. * In these studies, the contributors to the project discovered that the institutions of formal democracy that have recently re-emerged in many countries of the Third World have failed to broaden popular political participation in a very meaningful way. They found little evidence to support the widespread assumption that formal electoral democratisation alone would bring about a lasting progressive breakthrough in these societies or that it is capable of solving their fundamental social and especially economic problems. What should more accurately be called 'elite democracies' in effect coexist with tacit military dictatorships. Social reform agendas that could have established the basis for broader popular participation and greater social justice have been abandoned. Human rights violations continue virtually unabated. The new regimes are more readily manipulated by external forces such as the International Monetary Fund or via bilateral political and economic pressures, particularly from the USA. Economic policies often mandate austerity for the majority without, in most cases, bringing about significant economic growth. Progressive movements find it virtually impossible to implement an agenda for reform when powerful domestic and international groups opposing such change, not least the military, remain in place.
TL;DR: The results of a 3-year, placebo-controlled trial of prednisolone treatment in primary biliary cirrhosis (PBC) are presented in this article, where the active and placebo groups were initially well matched for age, menopausal status and disease severity.
TL;DR: In this study the head circumference and heights of 354 adults in two British centres were measured and the centile charts constructed from these measurements show that adult head circumference is related to height.
Abstract: Reference range for head circumference on the Tanner charts do not go beyond age 16. In this study the head circumference and heights of 354 adults in two British centres were measured. The centile charts constructed from these measurements show that adult head circumference is related to height. The mean head circumference of a male of average height is above the 97th centile for a 16 year old on the Tanner charts. The paediatric charts are therefore inappropriate for use in adult males.
TL;DR: The results suggest that the ITT is a suitable method of assessing insulin sensitivity and will be particularly useful in epidemiological studies, although the requirement for arterialized blood adds a measure of complexity.
Abstract: The glucose clamp technique is currently regarded as the standard test for measuring insulin sensitivity against which other methods are compared but is unsuitable for routine screening of patients outside a hospital base There is thus a need for a simpler test to measure insulin sensitivity We have therefore compared the glucose disappearance rate KITT in the first 15 min of the insulin tolerance test (ITT) with the M and M/I values derived from the standard euglycaemic clamp in nine normal subjects and eight subjects with Type 2 (non-insulin dependent) diabetes mellitus and coexisting obesity All subjects underwent the ITT and euglycaemic clamp in random order Nine subjects later had a repeat ITT to determine the reproducibility of the test In the ITT, 01 U kg-1 body weight, human Actrapid insulin was given as an IV bolus and simultaneous arterialized and venous blood samples were obtained every minute for 15 min The first order rate constant for the disappearance of glucose KITT over the period 3-15 min was taken as a measure of insulin sensitivity The euglycaemic clamp was performed with an insulin infusion of 50 mU kg-1 h-1 for 120 min and a variable rate glucose infusion to maintain blood glucose concentration at 05 mmol l-1 below fasting level to minimize the effect of endogenous insulin secretion The ratio of the mean rate of glucose infused (M, mumol kg-1 min-1) to the plasma insulin over the last 30 min of the clamp was taken as a measure of tissue sensitivity to insulin (M/I) assuming endogenous glucose output was suppressed(ABSTRACT TRUNCATED AT 250 WORDS)
TL;DR: It is concluded that nifedipine therapy results in significant gingival changes, an effect which may be mediated by the drug's action on calcium transport.
Abstract: The gingival health of 19 patients with cardiovascular problems who were medicated with nifedipine was compared with a similar cohort treated with atenolol and a control group of healthy patients. In the nifedipine and atenolol groups, patients had been taking their respective medication for a minimum period of 6 months. Plaque scores were similar for all three groups. However, patients medicated with nifedipine had a significantly higher gingival index (P less than 0.005), gingival overgrowth scores (P less than 0.02) and probing sites greater than 3 mm (P less than 0.005) when compared with the atenolol and control groups. 4 patients in the nifedipine group experienced clinically significant gingival overgrowth which required surgical excision. Gingival changes in the nifedipine patients were not related to drug dosage or plaque scores. It is concluded that nifedipine therapy results in significant gingival changes, an effect which may be mediated by the drug's action on calcium transport.
01 Jan 1992
TL;DR: A new Petri net calculus called the calculus of Petri Boxes is described, designed to allow reasoning about the structure of a net and about the relationship between nets, and to facilitate the compositional semantic translation of high level constructs into elementary Petri nets.
Abstract: A new Petri net calculus called the calculus of Petri Boxes is described. It has been designed to allow reasoning about the structure of a net and about the relationship between nets, and to facilitate the compositional semantic translation of high level constructs such as blocks, variables and atomic actions into elementary Petri nets. The calculus is located ‘midway’ in such a translation.
TL;DR: In this article, a critique of the arguments put forward by Michael Storper and Susan Christopherson which suggest that the development of Hollywood's motion picture industry can be understood in terms of the flexible specialization perspective is presented.
Abstract: This article undertakes a critique of the arguments put forward by Michael Storper and Susan Christopherson which suggest that the development of Hollywood's motion picture industry can be understood in terms of the flexible specialization perspective. It puts forward an alternative perspective that views transformations in the film and media industries in terms, rather, of increasing globalism and corporate integration. This alternative approach is rooted in the particular properties of the media industries and media product. Copyright 1992 by Oxford University Press.
TL;DR: It is demonstrated that altered expression of the epidermal growth factor receptor and p53 protein occurs in prostate cancer, but were not associated with other features of prognostic importance such as stage or grade.