Showing papers by "University of Stirling published in 1996"

Gender as a determinant of small business performance: insights from a British study

Abstract: The performance of small businesses, that is the ability of small firms to contribute to job and wealth creation through business start-up, survival and growth, has been an important area of policy and academic debate in the 1980s. Surprisingly little has been written about gender and small business performance. Our literature search revealed only a small number of studies of any substance on this subject, though over forty made some mention of it, Most studies shied away from direct examination of quantitative performance measures (such as jobs created, sales turnover, annual growth), tending to concentrate on qualitative measures of success or failure. The paper examines small business performance and gender using data obtained from a survey of 600 (300 women, 300 men) Scottish and English small business ownermanagers, part of a three year study on the impact of gender on small business management. Analyses suggest that the relationship between gender and small business performance is complex, but that gender still appears to be a significant determinant even after other key factors are controlled for.

Fatty acid metabolism in freshwater fish with particular reference to polyunsaturated fatty acids

Abstract: Fatty acids in fish can arise from two sources: synthesis de novo from non‐lipid carbon sources within the animal, or directly from dietary lipid. Acetyl‐CoA derived mainly from protein can be converted to saturated fatty acids via the combined action of acetyl‐CoA carboxylase and fatty acid synthetase. The actual rate of fatty acid synthesis de novo is inversely related to the level of lipid in the diet. Freshwater fish can de‐saturate endogenously‐synthesized fatty acids to monounsaturated fatty acids via a A9 desaturase but lack the necessary enzymes for complete de novo synthesis of polyunsaturated fatty acids which must therefore be obtained preformed from the diet. Most freshwater fish species can desaturate and elongate 18:2(n‐6) and 18:3(n‐3) to their C20 and C22 homologues but the pathways involved remain ill‐defined. Cyclooxygenase and lipoxygenase enzymes can convert C20 polyunsaturated fatty acids to a variety of eicosanoid products. The dietary ratio of (n‐3) to (n‐6) polyunsaturated fatty ac...

The Problem of Reflexivity in Organizational Research: Towards a Postmodern Science of Organization

Abstract: This paper argues that contemporary organizational research and theorizing are circumscribed by the ontological commitments of being-realism. Being-realism is a fundamental ontological posture which asserts the primacy of `things', `entities', `events', `generative mechanisms', etc., as making up our material and social world. It underwrites the dominant academic predisposition which treats relatively unproblematic notions such as `the organization', its `goals', `environment', `strategies', etc., as theoretically legitimate objects of analysis. It also underwrites the preoccupations of organizational `meta-theorists' who impute an objective existence to their self-generated typologies and paradigmatic schemas and then proceed to compare them as if the ontological status of their objects of analyses were unproblematic. More recent reflexive organization theorists who draw attention to the ideological character of theories of organization do much to undermine the epistemological status of representationali...

Cell culture isolation of piscine neuropathy nodavirus from juvenile sea bass, Dicentrarchus labrax.

Abstract: A virus causing a vacuolating encephalopathy and retinopathy in juvenile sea bass, Dicentrarchus labrax, was isolated from brain tissue in a fish cell line (SSN-1) derived from striped snakehead, Channa striatus. The isometric, non-enveloped, 30 nm diameter virus particles were resistant to pH 2–9 and heating at 56 °C for 30 min. Infectious particles had a buoyant density of approximately 1.31 g/cm3 in CsCl. Two structural polypeptides of molecular mass 40 and 42 kDa were identified and the ssRNA consisted of two fragments of molecular mass 1.10 and 0.51 × 106 Da. From these characteristics the virus was identified as a nodavirus. Due to the broad range of susceptible fish hosts and the consistent neuropathology of the disease condition, the generic term piscine neuropathy nodavirus (PNN) is proposed for this infectious agent.

Face processing : human perception and principal components analysis

Abstract: Principal components analysis (PCA) of face images is here related to subjects’ performance on the same images. In two experiments subjects were shown a set of faces and asked to rate them for distinctiveness. They were subsequently shown a superset of faces and asked to identify those that had appeared originally. Replicating previous work, we found that hits and false positives (FPs) did not correlate: Those faces easy to identify as being “seen” were unrelated to those faces easy to reject as being “unseen.” PCA was performed on three data sets: (1) face images with eye position standardized, (2) face images morphed to a standard template to remove shape information, and (3) the shape information from faces only. Analyses based on PCA of shape-free faces gave high predictions of FPs, whereas shape information itself contributed only to hits. Furthermore, whereas FPs were generally predictable from components early in the PCA, hits appeared to be accounted for by later components. We conclude that shape and “texture” (the image-based information remaining after morphing) may be used separately by the human face processing system, and that PCA of images offers a useful tool for understanding this system.

The practice and theory of automated timetabling

Abstract: This special volumecomprises revisedversions of a selectionof the papers thatwere presented at the 9th International Conference on the Practice and Theory of Automated Timetabling (PATAT) in Belfast between 10th and 13th August 2010. The PATAT conferences are held biennially and this is the second time that the Annals of Operations Research has provided the venue for such a special collection of papers. The first PATAT special volume of this journal (Volume 194) contains papers associated with the 8th conference which was held in Montreal in 2008. PATAT acts as an international forum for all aspects of timetabling, including educational timetabling, personnel rostering, sports timetabling, and transport scheduling. The conference series is particularly concerned both with closing the gap between timetabling theory and practice and with supporting multidisciplinary interactions. The collection of papers in this special volume reflect these aims. The conference in Belfast brought together approximately 100 participants from around the world. There were five plenary presentations, 74 standard talks, and 16 practitioner presentations. All the delegates were invited to submit their revised papers to this special volume. The papers have been through a rigorous and thorough review process, and we are delighted to be able to present the community with such an interesting and diverse selection of articles that reflect the latest thinking in timetabling research. We would like to take this opportunity to thank all those who were responsible for the success of the conference. We would particularly like to thank Brian Fleming and all those within the School of Electronics, Electrical Engineering andComputer Science at theQueen’s University of Belfast who worked so hard before and during the conference.

Giving to charity: questioning the donor decision process

Abstract: Notes that changes in the charity environment mean that fundraisers need to increase income from donations. Argues that to move forward donor behavior research needs to look not only at “why” people make donations but also at the process of “how” donations are made. Proposes that valuable lessons may be learnt through consideration of advances made in the field of consumer behavior where researchers have long focussed on decision‐making processes as a concept which is central to the understanding of how consumers behave. Suggests that taking account of the circumstances in which the consumer acts will give insight into donor behavior, which avoids losing sight of the reality of donation occasions.

Avian biochemistry and molecular biology

Abstract: The biology of birds is diverse and frequently differs significantly from that of other vertebrates. Many birds migrate or fly at high altitudes, while egg-laying and feather production places high demands on nutrient uptake and storage. This book is the only comprehensive and up-to-date survey of avian biochemistry and molecular biology available. It emphasises the similarities and differences between birds and other vertebrates, concentrating on new developments. The first section deals with protein, lipid and carbohydrate metabolism, its hormonal control and the adaptations that occur in birds. The second covers the avian genome, gene expression, and avian immunology. Growth and embryological development are also discussed. Avian Biochemistry and Molecular Biology will be of interest to all those working on birds, especially postgraduate students and researchers.

Analysis of aggregated parasite distributions: A comparison of methods

Abstract: 1. Empirically, parasite distributions are often best described by the negative binomial distribution; some hosts have many parasites while most have just a few. Thus identifying heterogeneities in parasite burdens using conventional parametric methods is problematical. In an attempt to conform to the assumptions of parametric analyses, parasitologists and ecologists frequently log-transform their overdispersed data prior to analysis. In this paper, we compare this method of analysis with an alternative, generalized linear modelling (GLM), approach. 2. We compare the classical linear model using log-transformed data (Model 1) with two GLMs: one with Poisson errors and an empirical scale parameter (Model 2), and one in which negative binomial errors are explicitly defined (Model 3). We use simulated datasets and empirical data from a long-term study of parasitism in Soay Sheep on St Kilda to test the efficacies of these three statistical models. 3. We conclude that Model 1 is much more likely to produce type I errors than either of the two GLMs, and that it also tends to produce more type II errors. Model 3 is only marginally more successful than Model 2, indicating that the use of an empirical scale parameter is only slightly more likely to generate errors than using an explicitly defined negative binomial distribution. Thus, while we strongly recommend the use of GLMs over conventional parametric analyses, either GLM method will serve equally well.

Effects of dietary (n-3) and (n-6) polyunsaturated fatty acid ratio on the immune response of Atlantic salmon, Salmo salar L.

Abstract: To examine the influence of the dietary ratio of (n-3) to (n-6) polyunsaturated fatty acids (PUFAs) on the immune system of Atlantic salmon, Salmo salar L., two dietary trials were carried out in which parr were maintained on diets containing either fish oil [(n-3)/(n-6) PUFA = 5.2] or sunflower oil [(n-3)/(n-6) PUFA = 0.3] and assessed for differences in immunological parameters. There were no significant differences in blood cell counts, differential leucocyte counts or haematocrit values between dietary groups, and while no apparent differences were observed in the non-specific immune parameters measured, there was a significantly higher number of B cells responding to Aeromonas salmonicida, in the kidney and spleen of vaccinated fish maintained on high (n-3)/(n-6) PUFAs diets. There was also a significant difference (P≤ 0.01) between the dietary groups in trial 1 and trial 2 when non-vaccinated fish were challenged with Aeromonas salmonicida and Vibrio anguillarum, respectively, with the (n-6) group succumbing to the bacterium before the (n-3) group. The results suggest that Atlantic salmon fed diets with a low ratio of (n-3)/(n-6) PUFA may be less resistant to infection than those fed diets containing lipid with a high (n-3)/(n-6) PUFA ratio.

Hearing the voice of people with dementia: Opportunities and obstacles

Abstract: Preface (Mary Marshall).Introduction. 1.The echoes return slow. 2.Hearing views about services. 3.Is there anyone in there? 4.Different people are affected in different ways. 5.Communication is possible. 6.Disempowerment. 7.A sense of time and pace. 8.The value of life story. 9.The effect of the environment. 10.Nonverbal communication. 11.Challenging behaviour. 12.Group work. 13.To tell or not to tell - is that the question? 14.A reflective conclusion.

System dynamics in project management: a comparative analysis with traditional methods

Abstract: Recent dramatic project failures have weaknesses in the traditional approaches to project management and in particular their failure to cope System dynamics models provide a useful tool for a more systematic management of these strategic issues. There have been a number of applications of system dynamics in project management; this experience permits a tentative comparison with the more traditional approaches and to examine the particular benefits of system dynamics. The conflicts of opinion between their supporters stress the different perspectives underlying the two approaches. The comparison of the approaches is focused on the “view” of the project management process. Although, ultimately, they both assume a system perspective, a cycle of planning, implementation and control, the level of detail in which they consider the project system is different. Traditional models . highlighted The increasing rate of change and the complexity of the new technologies and markets impose the need for quick and effective responses. As a consequence many organisations are now adopting “management by projects” as a general approach (Turner 1993) and project success is a primary factor for the survival and prosperity of organisations. However, projects are also becoming more complex and project failure is unfortunately another major trend. Over-runs of 40 to 200 per cent are common, while other projects are cancelled before completion but after considerable expenditure (Morris and Hough 1987). The important role of project management in modern life has highlighted some of the deficiencies of traditional techniques and the search for an alternative. Traditional techniques can encourage a narrow, operational view of the project, concentrating on the detailed planning and several studies (Davidson and Huot 1991; Morris and Hough 1987) have identified the need for a more strategic approach. Systems dynamics appears to offer this strategic alternative, assuming a holistic view of the organisation with an emphasis on the behavioural aspects of projects and their relation with managerial strategies. This paper addresses the need for a better understanding of the nature, differences, similarities, and purposes of traditional and system dynamics approaches. If system dynamics models are to play a core role in the future developments of project management, it is important to understand their distinctive contribution to the current body of knowledge and their place in a future methodology.

Dietary lipid affects phospholipid fatty acid compositions, eicosanoid production and immune function in Atlantic salmon (Salmo salar)

Abstract: Atlantic salmon (Salmo salar) post-smolts were fed diets containing either Fosol (FO), a North Sea fish oil, sunflower oil (SO), linseed oil (LO) or Marinol K (MO), a southern hemisphere fish oil rich in 20:5(n-3) for 12 weeks. A macrophage-enriched leucocyte preparation was obtained from head kidney and the fatty acid compositions of the individual membrane phospholipids measured. In general phospholipids from SO- and LO-fed fish had increased 18:2(n-6), 20:2(n-6) and 20:3(n-6) compared to the fish oil treatments while LO-fed fish had lower 20:4(n-6) than any other dietary treatment. Fish fed LO also had increased 18:3(n-3), 18:4(n-3), 20:3(n-3) and 20:4(n-3). The 20:5(n-3) content of kidney macrophage-enriched leucocyte phospholipids was highest in MO-fed fish followed by FO- and LO-fed fish with the lowest level in fish fed SO. The overall effect on the ratio of eicosanoid precursors, 20:420:5, showed the highest value in SO-fed fish and the lowest in fish fed LO. Production of LTB5 by kidney macrophage-enriched leucocytes stimulated with A23187 was highest in MO-fed fish and lowest in those fed SO. Production of LTB4 was greatest in SO-fed fish and lowest in fish fed LO. Serum lg levels were significantly affected by dietary treatment with highest values in fish fed FO and SO and lowest in fish fed MO and LO.

A land evaluation project in Greece using GIS and based on Boolean and fuzzy set methodologies

Abstract: In Mediterranean regions there is little experience in using GIS as an aid to land evaluation. This paper reports a project in Greece which investigated the usefulness of such technology, Particular emphasis was also given to comparing the results of land evaluation using Boolean and fuzzy set methodologies. The need was to produce the results as quickly and efficiently as possible to aid agricultural planning. By using a GIS, a series of single factor and land evaluation maps was produced for a range of crops; a land suitability map for receipt of sewage was also derived. A comparison of results from using Boolean and fuzzy set methodologies highlighted the advantages of the latter, although critical decisions are required on choice of membership functions and weights which have a major effect on the results.

Parameter extraction from population codes: a critical assessment

Abstract: In perceptual systems, a stimulus parameter can be extracted by determining the center-of-gravity of the response profile of a population of neural sensors. Likewise at the motor end of a neural system, center-of-gravity decoding, also known as vector decoding, generates a movement direction from the neural activation profile. We evaluate these schemes from a statistical perspective, by comparing their statistical variance with the minimum variance possible for an unbiased parameter extraction from the noisy neuronal ensemble activation profile. Center-of-gravity decoding can be statistically optimal. This is the case for regular arrays of sensors with gaussian tuning profiles that have an output described by Poisson statistics, and for arrays of sensors with a sinusoidal tuning profile for the (angular) parameter estimated. However, there are also many cases in which center-of-gravity decoding is highly inefficient. This includes the important case where sensor positions are very irregular. Finally, we study the robustness of center-of-gravity decoding against response nonlinearities at different stages of an information processing hierarchy. We conclude that, in neural systems, instead of representing a parameter explicitly, it is safer to leave the parameter coded implicitly in a neuronal ensemble activation profile.

Horizontalism: a critique

Abstract: This article offers a critique of the horizontalist view of money that banks are passive in the face of credit demand. It is argued that banks' liquidity preference influences their responsiveness to the demand for credit. Their liquidity preference is expressed in risk assessment (understood in terms of John Maynard Keynes's theory of uncertainty). It is argued that rationing in the sense of adverse changes in risk assessment occurs systematically in the downturn of the business cycle. Systematic rationing also occurs with respect to particular classes of borrowers; the focus here is on the case of small firms. (c) 1996 Academic Press Limited Copyright 1996 by Oxford University Press.

An outbreak of amoebic gill disease in ireland

Abstract: Ultrasonography of portosystemic shunts

The role of general practice and the primary care team in dementia diagnosis and management

Abstract: General practitioners (GPs) and the primary care team are uniquely situated to play a central role both in the diagnosis and ongoing care of dementia. Anecdotal reports and empirical work suggest that GPs face several challenges in fulfilling this role. This paper describes the various roles GPs and the primary care team could play in diagnosis and ongoing management. It then discusses the legitimate anxieties and difficulties faced in fulfilling these roles. The paper concludes with suggestions for how GPs and the primary care team might be supported to maximize their role in dementia diagnosis and management.

Schizophrenia as a membrane lipid disorder which is expressed throughout the body

Abstract: Clinical, biochemical and genetic evidence now indicates that schizophrenia is a disorder of membrane phospholipid metabolism associated with increased loss of highly polyunsaturated fatty acids from membranes owing to enhanced activity of a phospholipase A2. This changes the properties of membranes throughout the body and is responsible for such physical abnormalities as reduced vasodilator responses to niacin and histamine and altered immunological functions. A modest membrane abnormality is likely to produce its most serious consequences in the brain, which requires the co-ordinated sequential and parallel activities of millions of neurons. The concept leads to testable proposals for relatively simple and safe treatment modalities.

Polyunsaturated fatty acids in neutral lipids and phospholipids of some freshwater insects

Abstract: The fatty acid compositions of total neutral lipids and total polar lipids from eight species of freshwater insects were determined: stonefly nymphs (Plecoptera), beetle larvae (Coleoptera), Chironomidae (Diptera), water boatmen (Corixidae and Notonecta; Heteroptera) and mayfly nymphs (Ecdyonurus venosus, Caenis, Ephemerella; Ephemeroptera). In addition, the compositions of individual phosphoglycerides were deter- mined for four of the species (Plecoptera, Corixidae, Ecdyonurus venosus and Emphemerella). Saturated and monounsaturated fatty acids together represented up to 85% of the fatty acids of total neutral lipids with 16:0 (18-31%) being the most abundant saturated fatty acid and 16:ln-7 (10-28%), 18:ln-9 (6-12%) and 18: ln- 7 (3-12%) the most abundant monounsaturates. Polyunsaturated fatty acids (PUFA) accounted for between 16% and 33% of the total fatty acids of neutral lipids, with 20:5n-3 (4-12%), 18:3n-3 (3-30%) and 18:2n-6 (1-8%) all being major components. Arachidonic acid, 20:4n-6 (0.4-1.0%) and 22:6n-3 were, respectively, minor and insignificant components of total neutral lipids. PUFA were major fatty acids (34-56% of the total) in total polar lipids and in phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and phosphati- dylinositol. The major PUFA present were 20:5n-3 (14-27%) and 18:3n-3 (6-23%). The most abundant n- 6 PUFA, especially in phosphoglycerides from Corixidae, was 18:2n-6 (3-11%). Arachidonic acid, 20:4n-6, was present in all phosphoglycerides accounting for 1-4% of the total fatty acids, except in the phosphatidylinosi- tol of Corixidae where it accounted for 12% of the total. 22:6(n-3) was not present in significant amounts in any phosphoglyceride in any species. 18:ln-9 (8-20%) and 18:ln-7 (2-14%) were the most abundant monoun- saturated fatty acids, especially in phosphatidylethanolamine. 16:0 was abundant in phosphatidylcholine (11- 21%), and 18:0 (17-23%) was abundant in phosphatidylserine. The results are discussed in relation to the functions and origins of PUFA in freshwater insects. COMP BIOCHEM PHYSIOL 114B, 161-170, 1996.

Towards an Epistemology of Social Representations

Abstract: L'A. propose une analyse epistemologique de la notion de representation sociale. Il affirme que ce type de theorie incorpore certain concepts tires de la tradition post-hegelienne. Il porte plus particulierement son attention sur les oppositions entre individu et societe, entre implicite et explicite, entre conscient et inconscient. Il presente et met en relation la theorie des representations sociales et la theorie socio-culturelle de la connaissance

Membrane fatty acids, niacin flushing and clinical parameters

Abstract: Clinical definitions of schizophrenia are unreliable and difficult to use. The niacin flush test, which involves prostaglandin-induced vasodilatation, offers a method of exploring essential fatty acid metabolism in schizophrenic patients and may serve to define a subgroup of patients. In a multicentre study of schizophrenic patients with negative symptoms, we have examined the clinical accompaniments of the niacin response. Patients failing to flush with niacin showed significantly reduced levels of arachidonic and docosahexaenoic acids. Conversion from non-flushing to flushing during the 6 month supplementation period was predicted by an increase in arachidonic acid levels in red blood cell membranes irrespective of nature of supplementation. In this study, patients were selected for their negative symptoms and, therefore, it was not surprising that further measures of negative or positive symptoms did not predict flushing. However, an increased score for affective symptoms was significantly associated with a positive flush response. The stability of the niacin test needs to be examined in relation to the periodicity of symptoms in schizophrenia and manic depressive illness. New information on the anandamide system suggests that it may be associated with periodic phenomena and should be investigated in relation to the niacin test.