Showing papers by "Cardiff University published in 1989"

Changes in asthma prevalence: two surveys 15 years apart.

Abstract: In 1973 a survey was conducted among 12 year old children living in a defined area of South Wales. In 1988 the survey was repeated in the same area, again among 12 year old children. Questionnaires were completed for all 965 children in the population sample; peak expiratory flow rates were performed on them all, and repeated (except for five children) after an exercise provocation test. The prevalence of a history of wheeze at any time had increased from 17% to 22%, while that of a history of asthma at any time had increased from 6% to 12%. Current asthma had increased from 4% to 9%, but wheezing in the past year not attributed to asthma had remained at 6%. The exercise provocation tests suggested that both mild and severe asthma had become more common. Increases had also occurred in the frequencies of a history of eczema (from 5% to 16%) and of hay fever (from 9% to 15%). It seems that the prevalence of asthma has risen, and that this cannot be wholly explained by a greater readiness to diagnose the disease.

Screening and monitoring instrument

Abstract: Apparatus for indicating a predisposition to kidney stone disease in humans, and also dehydration, and for monitoring the efficacy of hydration therapy, comprises a conductivity probe including a tip which can be inserted into urine so that a drop thereof adheres to the tip, and display means for indicating the result as a derived function of conductivity (electrolyte concentration) in terms of urine specific gravity or osmolality. Preferably the probe electrodes are small and are spaced closely together so that the streamlines between the electrode tips are such that maximum current flows substantially within the adherent drop of urine.

Repeat-Buying: Facts, Theory and Applications

Abstract: 1. Repeat‐buying: Facts, Theory and Applications. By A. S. C. Ehrenberg, ISBN 0 19 5206347. Griffin, London, 1988. 378 pp. £29.50.

Scintillation proximity assay

Abstract: Fluomicrospheres coated with antibodies or receptors eliminate the need to separate bound from free ligand in both radioimmunoassays and ligand-binding assays.

An assessment of the fit of a parabolic curve to pre- and post-treatment dental arches.

Abstract: Study casts of the teeth are routinely used for diagnosis and to assess treatment change: the crowding of the teeth or shortage of space available within the dental arch is usually assessed visually. A full cast analysis program has been developed previously, making use of the three-dimensional Reflex Plotter linked to a computer. This study examines the validity of the fit of computer generated parabolic curves to dental arches, as performed in the measurement of crowding. Using a visual analogue method it was found that the parabola appeared to fit lower post-treatment dental arches best. However, reservations regarding the fit of symmetrical curves are expressed and other solutions suggested.

Highly sensitive assays of autoantibodies to thyroglobulin and to thyroid peroxidase.

Abstract: These highly sensitive assays are based on the interaction between thyroid autoantibodies and 125I-labeled autoantigens. Serum samples are incubated with labeled thyroid peroxidase (TPO) or thyroglobulin (Tg) to allow the formation of antibody-labeled antigen complexes. The complexes are then precipitated by addition of solid-phase Protein A. In the presence of high concentrations of TPO antibody or Tg antibody, more than 50% of the respective labeled antigen was precipitated, whereas only 1-2% was precipitated in the absence of autoantibody. Interassay CVs were 3.2% and 5.7%, respectively, for the anti-TPO and anti-Tg assays. There was no cross-reactivity between Tg antibody and TPO antibody. Results correlated highly significantly with results from other assay systems based on antigen-coated cells or plastic supports, but the assays described here were considerably more sensitive. Scatchard analysis of the assay data provided information on the affinity and serum concentration of TPO autoantibodies (ka approximately 10(9) L/mol and concentrations up to 1 g/L) and Tg autoantibodies (ka approximately 4 x 10(10) L/mol and concentrations up to 1 g/L). Overall, these assays provide a sensitive, precise, and convenient system for measuring and investigating the properties of thyroid autoantibodies.

Explosive volcanism on Santorini, Greece

Abstract: Santorini volcanic field has had 12 major (1–10 km3 or more of magma), and numerous minor, explosive eruptions over the last ~ 200 ka. Deposits from these eruptions (Thera Pyroclastic Formation) are well exposed in caldera-wall successions up to 200 m thick. Each of the major eruptions began with a pumice-fall phase, and most culminated with emplacement of pyroclastic flows. Pyroclastic flows of at least six eruptions deposited proximal lag deposits exposed widely in the caldera wall. The lag deposits include coarse-grained lithic breccias (andesitic to rhyodacitic eruptions) and spatter agglomerates (andesitic eruptions only). Facies associations between lithic breccia, spatter agglomerate, and ignimbrite from the same eruption can be very complex. For some eruptions, lag deposits provide the only evidence for pyroclastic flows, because most of the ignimbrite is buried on the lower flanks of Santorini or under the sea. At least eight eruptions tapped compositionally heterogeneous magma chambers, producing deposits with a range of zoning patterns and compositional gaps. Three eruptions display a silicic–silicic + mafic–silicic zoning not previously reported. Four eruptions vented large volumes of dacitic or rhyodacitic pumice, and may account for 90% or more of all silicic magma discharged from Santorini. The Thera Pyroclastic Formation and coeval lavas record two major mafic-to-silicic cycles of Santorini volcanism. Each cycle commenced with explosive eruptions of andesite or dacite, accompanied by construction of composite shields and stratocones, and culminated in a pair of major dacitic or rhyodacitic eruptions. Sequences of scoria and ash deposits occur between most of the twelve major members and record repeated stratocone or shield construction following a large explosive eruption. Volcanism at Santorini has focussed on a deep NE–SW basement fracture, which has acted as a pathway for magma ascent. At least four major explosive eruptions began at a vent complex on this fracture. Composite volcanoes constructed north of the fracture were dissected by at least three caldera-collapse events associated with the pyroclastic eruptions. Southern Santorini consists of pryoclastic ejecta draped over a pre-volcanic island and a ridge of early- to mid-Pleistocene volcanics. The southern half of the present-day caldera basin is a long-lived, essentially non-volcanic, depression, defined by topographic highs to the south and east, but deepened by subsidence associated with the main northern caldera complex, and is probably not a separate caldera.

Lipid metabolism in algae.

Abstract: Publisher Summary The lipid composition and metabolism of algae are exceptionally varied This chapter focuses on groups of organisms (algae) that have been studied in reasonable detail To lay a basis for further discussion of metabolism, the lipid structure and occurrence in algae is discussed The metabolic sections then deal with organisms of increasing complexity, from the primitive cyanobacteria to marine macroalgae Finally, the chapter ends with a discussion on green algae, which can be regarded as the nearest in metabolic characteristics to higher plants

Adaptive modifications in membranes of halotolerant and halophilic microorganisms

Abstract: Halotolerant and halophilic microorganisms can grow in (hyper)saline environments, but only halophiles specifically require salt. Genotypic and phenotypic adaptations are displayed by halophiles; the halotolerants adapt phenotypically, but it is not established whether they show genotypic adaptation. This paper reviews the various strategies of haloadaptation of membrane proteins and lipids by halotolerant and halophilic microorganisms. Moderate halophiles and halotolerants adapt their membrane lipid composition by increasing the proportion of anionic lipids, often phosphatidylglycerol and/or glycolipids, which in the moderately halophilic bacteriumVibrio costicola appears to be part of an osmoregulatory response to minimize membrane stress at high salinities. Extreme halophiles possess typical archaebacterial ether lipids, which are genotypically adapted by having additional substitutions with negatively-charged residues such as sulfate. In contrast to the lipids, it is less clear whether membrane proteins are haloadapted, although they may be more acidic; very few depend on salt for their activity.

The effect of oxygen on denitrification in Paracoccus denitrificans and Pseudomonas aeruginosa.

Abstract: Denitrification by Paracoccus denitrificans and Pseudomonas aeruginosa was studied using quadrupole membrane-inlet mass spectrometry to measure simultaneously and continuously dissolved gases. Evidence was provided for aerobic denitrification by both species: in the presence of O2, N2O production increased in Pa. denitrificans, while that of N2 decreased; with Ps. aeruginosa, the concentrations of both N2 and N2O increased on introducing O2 into the gas phase. Disappearance of NO-3 was monitored in anaerobically and aerobically grown cells which were maintained either anaerobically or aerobically: the rate and extent of NO-3 utilization by both species depended on growth and maintenance conditions. The initial rate of disappearance was most rapid under completely anaerobic conditions, and lowest rates occurred when cells were grown anaerobically and maintained aerobically. In nitrogen balance experiments both species converted over 87% of the added NO-3 to N2 and N2O under both anaerobic and aerobic maintenance conditions.

Making SWOT Analysis Work

Abstract: The analysis of Strengths and Weaknesses, and Opportunities and Threats is probably the most common and widely‐recognised tool for conducting a strategic marketing audit The authors suggest SWOT analysis has suffered from familiarity breeding contempt and that the technique is normally used very badly and to little effect The article draws on experience of marketing planning process management in a variety of companies to propose a five‐point approach to make SWOT analysis work effectively

A Comparison of the Toxicity and Efficacy of Cisplatin and Carboplatin in Advanced Ovarian Cancer

Abstract: Eighty-eight patients with stage IIB-III epithelial ovarian cancer were randomised to receive first line single agent cisplatin (100 mg/m2) monthly or carboplatin (400 mg/m2) monthly for up to 5 cycles. Crossover to the opposite analogue occurred with progression or lack of response. All patients were premedicated with i.v. methylprednisolone (500 mg at 0 hours and 250 mg at 3 hours) and the first 20 patients in both groups received lorazepam and prochloperazine for nausea and vomiting. The median number of vomiting episodes per cycle with cisplatin was 16 and with carboplatin 2 (p less than 0.001). In the cisplatin arm 27/40 (67.5%) developed mild renal toxicity, 9/40 (22.5%) WHO grade I neurotoxicity and 18/40 (45%) evidence of ototoxicity at audiometry. To date we have seen no neuro- or ototoxicity with carboplatin and 1/40 (2.5%) have developed WHO grade I renal toxicity. Myelosuppression and anaemia was more common with carboplatin but only 1 episode of grade IV thrombocytopenia has been seen with first line carboplatin. The clinical response rate (CR+PR) for cisplatin was 19/40 and for carboplatin 27/40. Actuarial survival for cisplatin group at 24 months was 50% and for carboplatin group 58% with no significant difference. Carboplatin appears less toxic than cisplatin producing to date similar survival and response as a single agent.

Environmental factors and symptoms in infants at high risk of allergy.

Abstract: STUDY OBJECTIVE: To identify environmental determinants of six symptoms associated with allergic disease in infancy. DESIGN: Infants were participants in a prospective randomised controlled trial of feeding practices in families with a history of atopy. SETTING: Infants were recruited in two maternity hospitals in S Wales and followed up in the community for 1 year. PARTICIPANTS: Mothers of 519 infants agreed to participate, but 36 were excluded (mainly for moving home or failing to attend for follow-up), leaving 483 in the study (253 male, 230 female). Infants were followed up and examined for evidence of allergic disease at 3, 6, and 12 months. MEASUREMENTS AND MAIN RESULTS: At each examination, mothers were questioned about episodes of illness in the infant, and the data presented relate to (reported and observed) eczema and nasal discharge, and (reported) wheeze, prolonged colds, diarrhoea and vomiting. Mothers kept a diary with details of feeding for the first 6 months. All homes were visited by a nurse who took samples of dust for dust mite antigen analysis. Extensive socio-demographic data were collected. None of the factors studied showed a convincing relationship with eczema. In a multiple logistic regression analysis breast feeding appeared to protect against wheeze, nasal discharge, colds, vomiting and diarrhoea. Having more siblings increased the likelihood of prolonged colds, and (together with overcrowding) of wheeze and nasal discharge. Maternal smoking and low social class were associated with wheeze, and house dust antigen with prolonged colds. Respiratory symptoms were associated with some aspects of housing but these could not be distinguished clearly from other social factors. Babies born in Autumn were at increased risk of wheeze, vomiting and diarrhoea. CONCLUSIONS: Environmental factors play an important part in determining risk of symptoms in potentially atopic babies. These factors are in principle open to manipulation.

Ocular complications of bone marrow transplantation.

Abstract: Thirty-four patients who had undergone bone marrow transplantation (BMT) were examined; 83.3% of those who received single shot and none of those who received fractionated total body irradiation (TBI) developed cataracts. The use of steroids to treat chronic Graft Versus Host Disease (GVHD) produced more severe cataracts in those who had allogeneic transplants after single shot TBI, but follow-up has not been long enough to assess their effect following fractionated TBI. Keratoconjunctivitis sicca (KCS) was seen in 81.8% of patients with chronic GVHD and in 33.3% of patients after autologous BMT.

Palaeomagnetic estimates of emplacement temperatures of pyroclastic deposits on Santorini, Greece

Abstract: Thermal remanent magnetism provides a method of quantitatively determining the emplacement temperature of individual lithic clasts in a volcaniclastic rock. The technique is reviewed and applied to two types of Quaternary pyroclastic deposit on Santorini. Emplacement-temperature estimates for lithic clasts from two co-ignimbrite lithic breccias (Cape Riva and Middle Pumice eruptions) range from 250°C to ≥ 580°C, showing unambiguously that the breccias were emplaced hot. Good precision on temperature estimates (about ±20°C) were obtained from the Cape Riva breccias. Lithics in a Plinian airfall deposit from the Middle Pumice eruption give less precise results because the primary magnetisation has been partly overprinted by chemical (and/or viscous) remanence, and some clasts may have rotated during compaction of the deposit. Temperatures from proximal airfall are consistent with welding of the deposit within 1.5 km from vent. Temperature estimates for lithic clasts further from vent scatter, but a falloff of temperature away from vent can be recognised if an average emplacement temperature for the whole deposit is identified at each location. The study highlights some difficulties in interpreting quantitative temperature estimates for prehistoric pyroclastic deposits.

Industrial relations climate: Testing a construct

Abstract: Using the concept of organizational climate, this paper reports a study conducted to validate a measure of industrial relations climate. Industrial relations climate is defined as a subset of organizational climate that pertains to the norms and attitudes reflecting union-management relationships in an organization. Data were collected by means of extensive interviews with management and union representatives, and by distributing a questionnaire to 729 employees in two organizations in Canada. The results showed the validity and the reliability of five scales measuring industrial relations climate. Four of the climate scales also demonstrated strong within-organization and within-group agreement (based on union/non-union membership, bargaining unit and departmental affiliation). The potential theoretical and practical use of this construct for future research is discussed.

Differences between the 7-spot and 2-spot ladybird beetles (Coccinellidae) in their toxic effects on a bird predator

Abstract: Experiments with nestling blue tits Parus caeruleus L. examined the effects of feeding them 7-spot ladybird Coccinella septem- punctata (L.), 2-spot ladybird Adalia bipunctata (L.) or controls Tenebrio sp. 2. A feeding rate of 5'/i 7-spot ladybirds per day 'killed' nestlings within 2 days. Three of six nestlings fed at half this rate survived 4 days. In contrast, all experimental birds survived sixty-four 2-spot ladybirds fed over 4 days (equivalent by weight to the high 7-spot diet). 3. Nestlings fed 7-spot ladybirds also grew more slowly than birds fed 2-spot ladybirds. The latter birds showed no difference in weight gain from the controls although they begged more strongly for food. 4. Cadavers of birds fed 7-spot ladybirds showed evidence of severe liver damage. 5. The results indicate a substantial difference between the ladybird species in their toxicity to nestling blue tits. They support the hypothesis that 2-spot ladybirds are largely-edible, polymorphic Batesian mimics of well-protected, monomorphic species such as the 7-spot ladybird.

Customer Satisfaction with Bank Services: A Multidimensional Space Analysis

Abstract: The nature and direction of the satisfactions that are delivered to consumers of bank services are explored, and the criteria used to evaluate these services are highlighted. The non‐metric multidimensional scaling technique enabled respondents′ perceptions to be represented spatially. It is revealed that respondents had high levels of satisfaction with regard to the location and accessibility of branches and ATMs, and acceptance of the current levels of banking fees; but expressed some caution in their evaluation of new and improved services.