Showing papers by "University of Auckland published in 1996"

R: A Language for Data Analysis and Graphics

Abstract: In this article we discuss our experience designing and implementing a statistical computing language. In developing this new language, we sought to combine what we felt were useful features from two existing computer languages. We feel that the new language provides advantages in the areas of portability, computational efficiency, memory management, and scoping.

The illness perception questionnaire: A new method for assessing the cognitive representation of illness

Abstract: The Illness Perception Questionnaire (IPQ) is a new method for assessing cognitive representations of illness. The IPQ is a theoretically derived measure comprising five scales that provides information about the five components that have been found to underlie the cognitive representation of illness. The five scales assess identity - the symptoms the patient associates with the illness, cause - personal ideas about aetiology, time-line - the perceived duration of the illness, consequences - expected effects and outcome and cure control - how one controls or recovers from the illness. The IPQ has a specific number of core items but allows the user to add items for particular patient groups or health threats. Data is presented supporting the reliability and validity of the IPQ scales in different chronic illness populations.

Analysis of mismatch repair genes in hereditary non–polyposis colorectal cancer patients

Abstract: Hereditary non–polyposis colorectal cancer (HNPCC) is an autosomal dominant disorder characterized by the early onset of colorectal cancer and linked to germline defects in at least four mismatch repair genes. Although much has been learned about the molecular pathogenesis of this disease, questions related to effective presymptomatic diagnosis are largely unanswered because of its genetic complexity. In this study, we evaluated tumors from 74 HNPCC kindreds for genomic instability characteristic of a mismatch repair deficiency and found such instability in 92% of the kindreds. The entire coding regions of the five known human mismatch repair genes were evaluated in 48 kindreds with instability, and mutations were identified in 70%. This study demonstrates that a combination of techniques can be used to genetically diagnose tumor susceptibility in the majority of HNPCC kindreds and lays the foundation for genetic testing of this relatively common disease.

The Strategic Hrm Debate and the Resource-Based View of the Firm

Abstract: This article examines the implications of the resource-based view of the firm for the theory of strategic HRM. the resource-based view points to the sources of human resource advantage in building organisational capability. In this way, it helps us to identify the various ways in which HRM contributes to the strategic management of the firm. More work must be done, however, to relate resource-based concepts to important premises in employment relations theory. While our existing research base suggests that it will be possible to identify particular firms in any industry and economy which have built human resource advantage, the article argues that comparative research will continue to show important national differences which affect the competitiveness of firms.

Role of patients' view of their illness in predicting return to work and functioning after myocardial infarction: longitudinal study

Abstract: Objective: To examine whether patients9 initial perceptions of their myocardial infarction predict subsequent attendance at a cardiac rehabilitation course, return to work, disability, and sexual dysfunction. Design: Patients9 perceptions of their illness were measured at admission with their first myocardial infarction and at follow up three and six months later. Setting: Two large teaching hospitals in Auckland, New Zealand. Subjects: 143 consecutive patients aged under 65 with their first myocardial infarction. Main outcome measures: Attendance at rehabilitation course; time before returning to work; measures of disability with sickness impact profile questionnaire for sleep and rest, social interaction, recreational activity, and home management; and sexual dysfunction. Results: Attendance at the rehabilitation course was significantly related to a stronger belief during admission that the illness could be cured or controlled (t=2.08, P=0.04). Return to work within six weeks was significantly predicted by the perception that the illness would last a short time (t=-2.52, P=0.01) and have less grave consequences for the patient (t=-2.87, P=0.005). Patients9 belief that their heart disease would have serious consequences was significantly related to later disability in work around the house, recreational activities, and social interaction. A strong illness identity was significantly related to greater sexual dysfunction at both three and six months. Conclusions: Patients9 initial perceptions of illness are important determinants of different aspects of recovery after myocardial infarction. Specific illness perceptions need to be identified at an early stage as a basis for optimising outcomes from rehabilitation programmes. Key messages Patients9 beliefs about their illness seem to influence recovery and rehabilitation on discharge from hospital Patients9 ideas about their illness cluster around five cognitive dimensions: identity, cause, time line, consequences, and beliefs about cure or control In this study a belief that the illness could be controlled or cured was related to subsequent attendance at a cardiac rehabilitation course. Perceptions that the illness would last a long time and have serious consequences were associated with a longer delay before returning to work The early identification of illness perceptions could improve the outcome of cardiac rehabilitation programmes

Secure deletion of data from magnetic and solid-state memory

Abstract: With the use of increasingly sophisticated encryption systems, an attacker wishing to gain access to sensitive data is forced to look elsewhere for information. One avenue of attack is the recovery of supposedly erased data from magnetic media or random-access memory. This paper covers some of the methods available to recover erased data and presents schemes to make this recovery significantly more difficult.

Critical role for β7 integrins in formation of the gut-associated lymphoid tissue

Abstract: Immune defence against pathogens entering the gut is accomplished by lymphocytes in the gut-associated lymphoid tissue (GALT), a major compartment of the immune system. The GALT, comprising Peyer's patches, lamina propria lymphocytes and intra-epithelial lymphocytes of the intestine, is populated by lymphocytes that migrate there from the vasculature. Here we report that, in mice deficient for the beta7 integrin subfamily of adhesion molecules, the formation of the GALT is severely impaired. This is probably due to a failure of beta7-/- lymphocytes to arrest and adhere to the vasculature at the site of transmigration into the GALT.

Tyrosine Kinase Inhibitors. 8. An Unusually Steep Structure−Activity Relationship for Analogues of 4-(3-Bromoanilino)-6,7-dimethoxyquinazoline (PD 153035), a Potent Inhibitor of the Epidermal Growth Factor Receptor

Abstract: 4-(3-Bromoanilino)-6,7-dimethoxyquinazoline (32, PD 153035) is a very potent inhibitor (IC50 0.025 nM) of the tyrosine kinase activity of the epidermal growth factor receptor (EGFR), binding competitively at the ATP site. Structure−activity relationships for close analogues of 32 are very steep. Some derivatives have IC50s up to 80-fold better than predicted from simple additive binding energy arguments, yet analogues possessing combinations of similar phenyl and quinazoline substituents do not show this “supra-additive” effect. Because some substituents which are mildly deactivating by themselves can be strongly activating when used in the correct combinations, it is proposed that certain substituted analogues possess the ability to induce a change in the conformation of the receptor when they bind. There is some bulk tolerance for substitution in the 6- and 7-positions of the quinazoline, so that 32 is not the optimal inhibitor for the induced conformation. The diethoxy derivative 56 [4-(3-bromoanilino)...

Conventional fuzzy control and its enhancement

Abstract: Conventional fuzzy control can be considered mainly composed of fuzzy two-term control and fuzzy three-term control. In this paper, more systematic analysis and design are given for the conventional fuzzy control. A general robust rule base is proposed for fuzzy two-term control, leaving the optimum tuning to the scaling gains, which greatly reduces the difficulties of design and tuning. The digital implementation of fuzzy control is also presented for avoiding the influence of the sampling time. Based on the results of previous fuzzy two-term controllers, a simplified fuzzy three-term controller is proposed to enhance performance. A two-level tuning strategy is also planned, which first tries to set up the relationship between fuzzy proportional/integral/derivative gain and scaling gains at the high level, and optionally tunes the control resolution at low level. Simulation of different order models show the characteristics of fuzzy control, effectiveness of the new design methodologies, and advantages of the enhanced fuzzy three-term control.

Testosterone therapy in glucocorticoid-treated men.

Abstract: Background: Treatment with glucocorticoid drugs is a valuable therapy, but the use of these drugs is associated with major side effects, including osteoporosis, muscle wasting, and obesity. In men who take glucocorticoids, circulating testosterone concentrations are reduced, and this might contribute to the changes in bone and soft-tissue mass. Objective: To assess the effect of testosterone replacement on these above-mentioned parameters in glucocorticoid-treated men. Methods: Fifteen asthmatic men who were receiving long-term glucocorticoid treatment were randomly allocated to receive therapy with testosterone esters (30 mg of proprionate, 60 mg of phenylprionate, 60 mg of isocaproate, and 100 mg of decanoate [Sustanon]) (250-mg/mo intramuscular depot injection) or to act as control subjects during 12 months. After a washout period for those men who were receiving testosterone, the groups were then crossed over and studied for a further 12 months. Bone density and body composition were assessed by dual-energy, x-ray absorptiometry. Paired or unpaired 2-tailed t tested were calculated. Unless otherwise stated, all values are given as mean±SEM. Results: Bone density in the lumbar spine increased 5.0%±1.4% (mean±SEM) ( P =.005) during testosterone supplementation, but it did not change during the control period (between-groups difference, P =.05). These changes were accompanied by a decrease in the indexes of bone turnover. There was a gain in body fat mass (2.1±0.06 kg, P =.01) and a loss of lean body mass (1.4±0.5 kg, P =.02) during the control period, with both changes being reversed by testosterone treatment ( P Conclusion: Testosterone treatment reverses the deleterious effects of glucocorticoid drugs on skeletal and soft tissues in men. (Arch Intern Med. 1996;156:1173-1177)

Energy and Photoinduced Electron Transfer in Porphyrin−Fullerene Dyads

Abstract: Time-resolved fluorescence and absorption techniques have been used to investigate energy and photoinduced electron transfer in a covalently linked free-base porphyrin−fullerene dyad and its zinc analog. In toluene, the porphyrin first excited singlet states decay in about 20 ps by singlet−singlet energy transfer to the fullerene. The fullerene first excited singlet state is not quenched and undergoes intersystem crossing to the triplet, which exists in equilibrium with the porphyrin triplet state. In benzonitrile, photoinduced electron transfer from the porphyrin first excited singlet state to the fullerene competes with energy transfer. The fullerene excited singlet state is also quenched by electron transfer from the porphyrin. Overall, the charge-separated state is produced with a quantum yield approaching unity. This state lives for 290 ps in the free-base dyad and 50 ps in the zinc analog. These long lifetimes suggest that such dyads may be useful as components of more complex light-harvesting systems.

Treatment Decision Making In Women Newly Diagnosed With Breast Cancer

Abstract: The purpose of this study was to explore the hypothesis that women with breast cancer had specific preferences about the degree of control they wanted over treatment decision making. One hundred fifty women, newly diagnosed with breast cancer, were interviewed and their preferences for participation in treatment decision making were established using a measurement tool designed to elicit decision-making preferences (Degner LF, Sloan JF. Decision making during serious illness: What role do patients really want to play? J Clin Epidemiol 1992;45:944-50). Two hundred women with benign breast disease served as a descriptive comparison group. Unfolding theory (Coombs CH. A theory of data. New York: John Wiley & Sons, 1964) provided a means of analyzing the data so that the degree of control preferred by each woman could be established. The majority of the newly diagnosed women preferred to play a passive role in treatment decision making, leaving the decision-making responsibility to their physician, whereas the benign control group preferred a collaborative role in which joint decisions could be made between the patient and the physician. The implications of the results for patient participation are discussed.

The response to levodopa in Parkinson's disease: imposing pharmacological law and order.

Abstract: The seemingly unpredictable response to levodopa in patients with Parkinson's disease can be understood as an interaction between several distinct pharmacological effects of levodopa. The most important are a short-duration response with a half-life of minutes to hours and a long-duration response with a half-life of days, superimposed on diurnal motor variation. A negative response characterized by brief worsening before and after the short-duration response and dyskinesia accentuate the short-duration response. These various responses are modified by disease progression and long-term levodopa therapy. Pharmacodynamic modeling of the short-duration response indicates that with time, the response becomes less graded and small changes in levodopa concentrations can produce big changes in response. In this setting, unpredictability arises from the variation in absorption and distribution of levodopa.

Functioning in chronic fatigue syndrome: Do illness perceptions play a regulatory role?

Abstract: The relationships between illness perceptions, coping and adjustment were investigated in the context of chronic fatigue syndrome (CFS). Self-reported illness perceptions, coping, disability levels and psychological well-being were assessed in a national sample of 233 CFS sufferers. A series of regression analyses indicated that illness perceptions explained a greater percentage of the variance in levels of disability and psychological well-being than did the coping strategies used by the participants to manage their illness. The illness perception components of illness identity, emotional causes, controllability and consequences had the strongest overall association with adjustment such that participants with a strong illness identity, who believed their illness was out of their control, caused by stress and had very serious consequences were most disabled and psychologically impaired. Disengagement coping strategies and venting emotions were also associated with greater disability and poorer psychological well-being, while positive reinterpretation and seeking social support were positively related to psychological well-being. The potential role of illness perceptions in the maintenance of CFS is discussed. Chronic fatigue syndrome (CFS), otherwise known as myalgic encephalomyelitis or post-viral fatigue syndrome, is an illness characterized by persistent debilitating fatigue of uncertain origin. A multiplicity of other symptoms are associated with CFS such as muscle and joint pain, fever, sleep disruption, and impaired memory and concentration. Prevalence rates for this disorder have been quoted between 7.4 and 37 per 100,000, depending on the sampling procedures and diagnostic criteria used (Gunn, Connel & Randall, 1993; Lloyd, Hickie, Boughton, Spencer & Wakefield, 1990; Price, North, Wessely & Fraser, 1992). The average age of onset is approximately 30 years, with well-educated white women being over represented in patient samples (Gunn el al., 1993).

A comparison of question scales used for measuring customer satisfaction

Abstract: Many different scales have been used to measure customer satisfaction. These scales can be divided into three main groups, being those measuring performance, disconfirmation and satisfaction. Reports on the design and execution of a study of hotel guests in which they were asked to rate the key service attributes of their stay using all three of these measurement scales. Repurchase intention and word‐of‐mouth effects were also measured. Compares the scales on the basis of reliability, convergent and discriminant validity, predictive validity, skewness, face validity and managerial value for directing a quality improvement programme. Shows the disconfirmation scale to be superior to both the performance and satisfaction scales on all these criteria except for predictive validity. In addition, the performance scale was generally better than the satisfaction scale on a number of these criteria.

Information needs and sources of information for women with breast cancer: a follow-up study.

Abstract: This paper reports a study which examined the specific information needs and sources of information for 105 women with breast cancer at two time points, the time of diagnosis and a mean of 21 months from diagnosis. At diagnosis the priority information needs concerned survival issues. Further from diagnosis survival issues were still a concern, but information about the risk to family members of getting breast cancer showed a significant increase in importance. Information about sexual attractiveness was ranked last at both the newly diagnosed and follow-up stages. Information sources at the time of diagnosis centred around the specialist breast care service, while further from diagnosis few professional or voluntary sector sources were utilized, with women receiving most of their information from media sources such as women's magazines. The relevance of these findings for nurses and other health care professionals is discussed.

Blood pressure and risk of stroke in patients with cerebrovascular disease. The United Kingdom Transient Ischaemic Attack Collaborative Group.

Abstract: There is widespread clinical uncertainty about lowering blood pressure in patients with ischaemic cerebrovascular disease This often manifests as comparatively high thresholds for starting treatment and modest targets in reducing blood pressure Concern has arisen partly from reports of a J shaped association between blood pressure and recurrent stroke in these patients1 This relation may, however, be because severe strokes are associated both with a fall in blood pressure2 and independently with a relatively high risk of stroke recurrence, rather than from any adverse effects of low blood pressure itself If this were true, then people with a history of minor cerebrovascular disease would have direct and continuous relations between usual blood pressure and risk of stroke, as observed in people without cerebrovascular disease3 Data from …

A model of intrauterine growth retardation caused by chronic maternal undernutrition in the rat: effects on the somatotrophic axis and postnatal growth.

Abstract: While it is well established that severe maternal undernutrition during pregnancy causes intrauterine growth retardation (IUGR), there has been relatively little study of the endocrine consequences and postnatal development of growth-retarded offspring. We have developed a model in the rat of IUGR by nutritional restriction of the mother throughout gestation and have examined the effects of fetal growth retardation on the endocrine and metabolic status during the perinatal period. Timed matings were performed in Wistar rats and dams were randomly assigned to one of two dietary treatment groups. Food was available ad libitum throughout pregnancy to a control group (at libitum group) and a restricted group was fed 30% of the ad libitum intake (restricted fed group). After birth, food was available ad libitum in both groups and litter size was adjusted to eight pups per litter. Dams lost a significant amount of body weight throughout gestation due to undernutrition but were able to catch up to the ad libitum group by day 10 postnatally. Litter size was not affected by maternal undernutrition. Maternal plasma IGF-I levels were significantly reduced in the restricted fed group throughout gestation (P < 0.001) but were not different postnatally. Maternal plasma IGF-binding proteins (IGFBPs)-1, -2 and -3 were significantly (P < 0.05) increased in the restricted fed dams. The mean body weights of fetuses in late gestation from the restricted fed dams were significantly lower (P < 0.001) in comparison with fetuses from control dams. Placental weights were also significantly (P < 0.01) reduced in the restricted fed compared with control dams. Body weights were significantly lower in the offspring of restricted fed dams than control dams from birth (P < 0.01) until 90 days of age (P < 0.05). Nose-rump length was reduced in the fetuses of the restricted fed group at day 22 of gestation (P < 0.001) until weaning (P < 0.05). Plasma IGF-I levels were significantly reduced in the pups of restricted fed dams from day 22 of gestation (P < 0.01) until postnatal day 9 (P < 0.05) but were not significantly different at the later time-points. Plasma insulin levels were significantly reduced in the pups of restricted fed dams at birth (P < 0.05) but not at later time-points. Plasma IGFBP-1 and -2 levels were significantly increased in the offspring from restricted fed dams at day 22 of gestation, at birth and at day 9 postnatally (P < 0.05). 125I-Bovine GH specific binding to liver membranes was significantly lower (P < 0.05) in offspring from restricted fed dams at 21 days of age but not at 90 days of age. These data demonstrate that nutritional deprivation in the pregnant rat leads to IUGR and postnatal growth failure and to changes in allometric growth patterns and endocrine parameters of the somatotrophic axis postnatally.

Sequential changes in the metabolic response in critically injured patients during the first 25 days after blunt trauma.

Abstract: BackgroundUnderstanding the changes in energy expenditure and body composition is essential for the optimal management of the critically injured, yet these changes have not been quantified within the current context of trauma care.MethodsTen critically injured patients (median Injury Severity Score

A normal mode model for acousto‐elastic ocean environments

Abstract: A normal mode method for propagation modeling in acousto‐elastic ocean waveguides is described. The compressional (p‐) and shear (s‐) wave propagation speeds in the multilayer environment may be constant or have a gradient (1/c2 linear) in each layer. Mode eigenvalues are found by analytically computing the downward‐ and upward‐looking plane wave reflection coefficients R1 and R2 at a reference depth in the fluid and searching the complex k plane for points where the product R1R2=1. The complex k‐plane search is greatly simplified by following the path along which |R1R2|=1. Modes are found as points on the path where the phase of R1R2 is a multiple of 2π. The direction of the path is found by computing the derivatives d(R1R2)/dk analytically. Leaky modes are found, allowing the mode solution to be accurate at short ranges. Seismic interface modes such as the Scholte and Stonely modes are also found. Multiple ducts in the sound speed profile are handled by employing multiple reference depths. Use of Airy function solutions to the wave equation in each layer when computing R1 and R2 results in computation times that increase only linearly with frequency.

Gold Is Smaller than Silver. Crystal Structures of (Bis(trimesitylphosphine)gold(I)) and (Bis(trimesitylphosphine)silver(I)) Tetrafluoroborate

Abstract: Although it may have gone largely unnoticed, there is considerable confusion in handbooks of physical data as well as in chemistry textbooks and periodic tables concerning the relative sizes of silver and gold atoms. Values quoted for the ionic or covalent radii for the most common oxidation state +1 are either approximately equal for the two metals or larger for gold than for silver.1-4 The Pauling covalent radii for the two metals are essentially equal, which is due to the fact that the “metallic radius” in the close-packed cubic lattices happens to be virtually the same [the lattice constants are 4.0862 (Ag) and 4.07825 A (Au),5 and the nearest-neighbor interatomic distances are 2.889 (Ag-Ag) and 2.884 A (Au-Au) for coordination number 12].6 On the other hand, recent theoretical calculations including relativistic and correlation effects consistently predict that gold should be significantly smaller than silver, a phenomenon which is generally referred to as the “relativistic contraction”.7-9 In more qualitative terms, the concept of the “Lanthanide contraction”,7,8 employed successfully for other radius discontinuities in the periodic table, also points in the same direction.10 It appears, however, that no attempt has been made to settle this simple question by an experiment which can give unambiguous results. The most straightforward approach to this problem would be a comparison of metal-to-ligand bond lengths in a set of complexes involving (a) the same ligands and counterions, (b) the same coordination number and geometry, (c) an isomorphous crystal lattice, and (d) equal experimental conditions. More often than not these conditions are not fulfilled, since Ag(I) and Au(I) cations form compounds which differ significantly in their basic structure,11,12 such that a direct comparison is not meaningful. We have now discovered that the pair of title compounds meets all criteria on which to base the desired direct comparison, and from accurate single-crystal work we find that gold(I) is indeed much smaller than silver(I), by almost 0.1 A.12 The two reference complexes are readily prepared from AgBF4 and two equiv of Mes3P in dichloromethane (95% yield, mp 193 °C) or from equimolar quantities of (Mes3P)AuCl, Mes3P, and AgBF4 in CH2Cl2 (98% yield, mp 232 °C), respectively. The products can be obtained as large, transparent, isomorphous crystals (trigonal, space group P3121, Z ) 3), which are stable to air, moisture, and light at ambient temperature.13 Their analytical and spectroscopic data are in full agreement with the proposed compositions.14 Selected crystal data for [(Mes3P)2M]BF4 presented in Table 1 show the close crystallographic resemblance of the two unit cells, which suggest a very similar crystal field environment for the individual components. Both compounds are ionic in the crystal with no significant sub-van der Waals contacts between the ions. The cations have a crystallographically imposed 2-fold axis passing through the metal atom perpendicular to the P-M-P axis and relating the two phosphine ligand propellers, which thus have the same directionality (leftor right-handed propellers).14 The metal atoms are essentially linearly two-coordinate with bond angles which deviate from perfect collinearity by less than 0.3°. Selected distances and angles are compared in Table 2. The structure of the cation of the gold complex is shown in Figure 1, and Figure 2 offers a superposition of the structures of the gold and silver complexes. It is obvious from this diagram that there is almost perfect agreement of all details except for the M-P distance, which is smaller for M ) Au than for M ) Ag by 0.09(1) A. Assuming a covalent radius of

Naming as Norming: ‘Race’, Gender, and the Identity Politics of Naming Places in Aotearoa/New Zealand:

Abstract: The process of naming places involves a contested identity politics of people and place. Place-names are part of the social construction of space and the symbolic construction of meanings about place. Accordingly, we argue that the names applied to places in Aotearoa assist in the construction of the symbolic and material orders that legitimate the dominance of a hegemonic Pakeha masculinism. Attempts to rename (and in doing so, reclaim) places are implicated in the discursive politics of people and place. The contestation of place-names in Otago/Murihiku, one of the southernmost regions of New Zealand, is examined. We present a discursive analysis of submissions made to the New Zealand Geographic Board in 1989–90 concerning a proposed reinstatement of Maori names in the area. In interpreting objections to renaming we suggest these objections articulated with and through a number of ‘commonsense’ notions about gender, ‘race’, culture, and nation which discursively (re)produced a hegemonic Pakeha masculini...

Teachers' Maxims in Language Teaching

Abstract: In recent years, there has been a growing interest in general research on teaching as well as research on L2 teachers, in the mental images, thoughts, and processes teachers employ while they teach. These mental processes are believed to provide interpretative frames which teachers use to understand and approach their own teaching. This article focuses on the nature and role of teaching principles. Observations of teachers and conversations with them about how they conduct their lessons suggest that teachers develop personal principles which inform their approach to teaching. These principles function like rules for best behaviour, or maxims, and guide many of the teachers' instructional decisions. The nature of teachers' maxims is discussed through analysis of teachers' accounts of their teaching and lesson protocols. Teachers' maxims appear to reflect cultural factors, belief systems, experience, and training, and the understanding of which maxims teachers give priority to and how they influence teachers' practices is an important goal in teacher development. Implications for teacher education are discussed. The final source of the knowledge base [of teaching] is the least codified of all. It is the wisdom of practice itself, the maxims that guide (or provide reflective rationalization for) the practice of able teachers. (Shulman, 1987, p. 11)