17 resultados para off-test age

em Aston University Research Archive


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Predicated on the assumption that employee careerist orientation resulting from organizational actions to cut costs constitutes a potential threat to their long-term profitability and success, this study proposed and tested a social exchange model of careerist orientation in the People's Republic of China. Specifically, it was hypothesized that organizational justice and career growth opportunities will be related to careerist orientation, but the relationship will be mediated by trust in employer. Structural equation modeling results provided support for the model. Trust in organization fully mediated the relationship between careerist orientation and its antecedents.

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Aim: To assess the repeatability of Eger macular stressometer (EMS) measures of photostress recovery and determine their association with other measures of visual function. Methods: EMS photostress recovery time was measured in 90 patients with bilateral exudative age related macular degeneration (AMD), 19 with bilateral atrophic AMD and 47 with both forms of the condition (mean age 79 (SD 13) years). Measurements were made on two occasions separated by 1 year. Intrasession repeatability was assessed by repeating the measures after a 10 minute recovery period at the first visit. Distance visual acuity was measured with a logMAR chart, near visual acuity with a MNRead chart at 25 cm, contrast sensitivity with a Pelli-Robson chart, and the presence of central visual disturbance assessed with an Amsler grid. A questionnaire was used to assess self reported difficulties with glare recovery. Results: The average EMS recovery time was 11.0 (SD 8.9) seconds, decreasing by 1.6 (5.2) seconds on repeated measurement (p<0.05). EMS photostress recovery was not correlated with visual function measures or subjective difficulties with lights (p>0.05). EMS photostress recovery time did not predict those whose vision decreased over the following year compared with those among whom it remained stable. Conclusions: The EMS test is not a useful tool in determining the severity or progression of AMD.

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Purpose: To assess repeatability and reproducibility, to determine normative data, and to investigate the effect of age-related macular disease, compared with normals, on photostress recovery time measured using the Eger Macular Stressometer (EMS). Method: The study population comprised 49 healthy eyes of 49 participants. Four EMS measurements were taken in two sessions separated by 1 h by two practitioners, with reversal of order in the second session. EMS readings were also taken from 17 age-related maculopathy (ARM), and 12 age-related macular degeneration (AMD), affected eyes. Results: EMS readings are repeatable to within ± 7 s. There is a statistically significant difference between controls and ARM affected eyes (t = 2.169, p = 0.045), and AMD affected eyes (t = 2.817, p = 0.016). The EMS is highly specific, and demonstrates sensitivity of 29% for ARM, and 50% for AMD. Conclusions: The EMS may be a useful screening test for ARM, however, direct illumination of the macula of greater intensity and longer duration may yield less variable results. © 2004 The College of Optometrists.

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Based on data from 2091 call centre representatives working in 85 call centres in the UK, central assumptions of affective events theory (AET) are tested. AET predicts that specific features of work (e.g. autonomy) have an impact on the arousal of emotions and moods at work that, in turn, co-determine job satisfaction of employees. AET further proposes that job satisfaction is an evaluative judgement that mainly explains cognitive-based behaviour, whereas emotions and moods better predict affective-based behaviour. The results support these assumptions. A clear separation of key constructs (job satisfaction, positive and negative emotions) was possible. Moreover, correlations between several work features (e.g. supervisory support) and job satisfaction were, in part, mediated by work emotions, even when controlling for gender, age, call centre type (in-house versus outsourced centres) and call centre size. Predictions regarding consequences of satisfaction and affect were partly corroborated as continuance commitment was more strongly related to job satisfaction than to positive emotions. In addition, affective commitment and health complaints were related to both emotions and job satisfaction to the same extent. Thus, AET is a fruitful framework for explaining why and how specific management strategies used for designing work features influence important organizational attitudes and well-being of employees. © 2006 British Academy of Management.

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Werner Sombart (1863-1941) may well have been the most famous and controversial social scientist in Germany during the early twentieth century. Highly influential, his work and reputation have been indelibly tainted by his embrace of National Socialism in the last decade of his life. Although Sombart left an enormous opus spanning disciplinary boundaries, intellectual reaction to his work inside and outside of Germany is divided and ambivalent. Sombart consistently responded to the social and political developments that have shaped the twentieth century. Economic Life in the Modern Age provides a representative sampling of those portions of Sombart's work that have stood the test of time. The volume opens with a substantial introduction reviewing Sombart's life and career, the evolution of his major intellectual concerns, his relation to Marx and Weber, and his political affiliation with the Nazis. The editors' selection of texts emphasizes areas of Sombart's economic and cultural thought that remain relevant, particularly to those intellectual trends that seek a more broadly based, cross-disciplinary approach to culture and economics. Sombart's writings on capitalism are represented by essays on the nature and origin of the market system and the diversity of motives among the bourgeoisie and the proletariat. Also included is an excerpt from Sombart's controversial The Jews and Modern Capitalism, exploring the widely perceived relation between economic life and Judaism as a religion. In essays on the economics of cultural processes, Sombart's comprehensive and expansive idea of cultural science yields prophetic insights into the nature of urbanism, luxury consumption, fashion, and the cultural secularization of love. The volume's final section consists of Sombart's reflections on the social influences of technology, the economic life of the future, and on socialism, including the influential essay "Why is there no Socialism in the United States." Encapsulating the most valuable aspects of his work, Economic Life in the Modern Age provides clear demonstration of Sombart's sense for fine cultural distinctions and broad cultural developments and the predictive power of his analyses. It will be of interest to sociologists, economists, political scientists, and specialists in cultural studies.

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Background: Age-related macular degeneration (ARMD) is the leading cause of visual disability in people over 60 years of age in the developed world. The success of treatment deteriorates with increased latency of diagnosis. The purpose of this study was to determine the reliability of the macular mapping test (MMT), and to investigate its potential as a screening tool. Methods: The study population comprised of 31 healthy eyes of 31 participants. To assess reliability, four macular mapping test (MMT) measurements were taken in two sessions separated by one hour by two practitioners, with reversal of order in the second session. MMT readings were also taken from 17 age-related maculopathy (ARM), and 12 AMD affected eyes. Results: For the normal cohort, average MMT scores ranged from 85.5 to 100.0 MMT points. Scores ranged from 79.0 to 99.0 for the ARM group and from 9.0 to 92.0 for the AMD group. MMT scores were reliable to within ± 7.0 points. The difference between AMD affected eyes and controls (z = 3.761, p = < 0.001) was significant. The difference between ARM affected eyes and controls was not significant (z = -0.216, p = 0.829). Conclusion: The reliability data shows that a change of 14 points or more is required to indicate a clinically significant change. This value is required for use of the MMT as an outcome measure in clinical trials. Although there was no difference between MMT scores from ARM affected eyes and controls, the MMT has the advantage over the Amsler grid in that it uses a letter target, has a peripheral fixation aid, and it provides a numerical score. This score could be beneficial in office and home monitoring of AMD progression, as well as an outcome measure in clinical research. © 2005 Bartlett et al; licensee BioMed Central Ltd.

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The work described represents a palynological study of Carboniferous coal seams of Upper Westphallan. A and Westphalian B age from eight off-shore boreholes sunk by the National Coal Board in Northumberland. When treated chemically the majority of the coal samples yielded well-preserved miospores which were studied by means of the optical and scanning electron microscopes. Systematic descriptions of 151 miospore species belonging to 57 genera, and including 18 new types, are given. One miospore assemblage is recognised from the coals of Upper Westphalian A age and two fUrther assemblages from those of Westphalian B age, These compare with assemblages described by earlier workers from strata of similar age elsewhere, but there are differences in the distributions of some of the more abundant taxa, and some of the stratigraphically significant species are not present. Correlations based on miospore distributions between the coal seams encountered in the eight off-shore boreholes agree fairly closely with those established by the National Coal Board on lithological criteria. Relations are discussed between palynology and palaeoecology and detailed comparisons made with the work of Smith and Butterworth 1967 from the adjacent on-shore area. It is concluded that the miospore assemblages described are restricted in that they contain very low representation of Smith's (1962) Densospore phase. This restriction, due to the relatively rapid subsidence of the depositional area, is reflected in the distributions of some of the less common spores as · well as in the abundances of species such as Densosporites sphaerotriangularis, Lycospora pusilla and Apiculatisporis irregularis.

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A critical review of previous research revealed that visual attention tests, such as the Useful Field of View (UFOV) test, provided the best means of detecting age-related changes to the visual system that could potentially increase crash risk. However, the question was raised as to whether the UFOV, which was regarded as a static visual attention test, could be improved by inclusion of kinetic targets that more closely represent the driving task. A computer program was written to provide more information about the derivation of UFOV test scores. Although this investigation succeeded in providing new information, some of the commercially protected UFOV test procedures still remain unknown. Two kinetic visual attention tests (DRTS1 and 2), developed at Aston University to investigate inclusion of kinetic targets in visual attention tests, were introduced. The UFOV was found to be more repeatable than either of the kinetic visual attention tests and learning effects or age did not influence these findings. Determinants of static and kinetic visual attention were explored. Increasing target eccentricity led to reduced performance on the UFOV and DRTS1 tests. The DRTS2 was not affected by eccentricity but this may have been due to the style of presentation of its targets. This might also have explained why only the DRTS2 showed laterality effects (i.e. better performance to targets presented on the left hand side of the road). Radial location, explored using the UFOV test, showed that subjects responded best to targets positioned to the horizontal meridian. Distraction had opposite effects on static and kinetic visual attention. While UFOV test performance declined with distraction, DRTS1 performance increased. Previous research had shown that this striking difference was to be expected. Whereas the detection of static targets is attenuated in the presence of distracting stimuli, distracting stimuli that move in a structured flow field enhances the detection of moving targets. Subjects reacted more slowly to kinetic compared to static targets, longitudinal motion compared to angular motion and to increased self-motion. However, the effects of longitudinal motion, angular motion, self-motion and even target eccentricity were caused by target edge speed variations arising because of optic flow field effects. The UFOV test was more able to detect age-related changes to the visual system than were either of the kinetic visual attention tests. The driving samples investigated were too limited to draw firm conclusions. Nevertheless, the results presented showed that neither the DRTS2 nor the UFOV tests were powerful tools for the identification of drivers prone to crashes or poor driving performance.

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Background - An evaluation of standard automated perimetry (SAP) and short wavelength automated perimetry (SWAP) for the central 10–2 visual field test procedure in patients with age-related macular degeneration (AMD) is presented in order to determine methods of quantifying the central sensitivity loss in patients at various stages of AMD. Methods - 10–2 SAP and SWAP Humphrey visual fields and stereoscopic fundus photographs were collected in 27 eyes of 27 patients with AMD and 22 eyes of 22 normal subjects. Results - Mean Deviation and Pattern Standard Deviation (PSD) varied significantly with stage of disease in SAP (both p<0.001) and SWAP (both p<0.001), but post hoc analysis revealed overlap of functional values among stages. In SWAP, indices of focal loss were more sensitive to detecting differences in AMD from normal. SWAP defects were greater in depth and area than those in SAP. Central sensitivity (within 1°) changed by -3.9 and -4.9 dB per stage in SAP and SWAP, respectively. Based on defect maps, an AMD Severity Index was derived. Conclusions - Global indices of focal loss were more sensitive to detecting early stage AMD from normal. The SWAP sensitivity decline with advancing stage of AMD was greater than in SAP. A new AMD Severity Index quantifies visual field defects on a continuous scale. Although not all patients are suitable for SWAP examinations, it is of value as a tool in research studies of visual loss in AMD.

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Purpose. We describe the profile and associations of anisometropia and aniso-astigmatism in a population-based sample of children. Methods. The Northern Ireland Childhood Errors of Refraction (NICER) study used a stratified random cluster design to recruit a representative sample of children from schools in Northern Ireland. Examinations included cycloplegic (1% cyclopentolate) autorefraction, and measures of axial length, anterior chamber depth, and corneal curvature. ?2 tests were used to assess variations in the prevalence of anisometropia and aniso-astigmatism by age group, with logistic regression used to compare odds of anisometropia and aniso-astigmatism with refractive status (myopia, emmetropia, hyperopia). The Mann-Whitney U test was used to examine interocular differences in ocular biometry. Results. Data from 661 white children aged 12 to 13 years (50.5% male) and 389 white children aged 6 to 7 years (49.6% male) are presented. The prevalence of anisometropia =1 diopters sphere (DS) did not differ statistically significantly between 6- to 7-year-old (8.5%; 95% confidence interval [CI], 3.9–13.1) and 12- to 13-year-old (9.4%; 95% CI, 5.9–12.9) children. The prevalence of aniso-astigmatism =1 diopters cylinder (DC) did not vary statistically significantly between 6- to 7-year-old (7.7%; 95% CI, 4.3–11.2) and 12- to 13-year-old (5.6%; 95% CI, 0.5–8.1) children. Anisometropia and aniso-astigmatism were more common in 12- to 13-year-old children with hyperopia =+2 DS. Anisometropic eyes had greater axial length asymmetry than nonanisometropic eyes. Aniso-astigmatic eyes were more asymmetric in axial length and corneal astigmatism than eyes without aniso-astigmatism. Conclusions. In this population, there is a high prevalence of axial anisometropia and corneal/axial aniso-astigmatism, associated with hyperopia, but whether these relations are causal is unclear. Further work is required to clarify the developmental mechanism behind these associations.

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Background: Screening for congenital heart defects (CHDs) relies on antenatal ultrasound and postnatal clinical examination; however, life-threatening defects often go undetected. Objective: To determine the accuracy, acceptability and cost-effectiveness of pulse oximetry as a screening test for CHDs in newborn infants. Design: A test accuracy study determined the accuracy of pulse oximetry. Acceptability of testing to parents was evaluated through a questionnaire, and to staff through focus groups. A decision-analytic model was constructed to assess cost-effectiveness. Setting: Six UK maternity units. Participants: These were 20,055 asymptomatic newborns at = 35 weeks’ gestation, their mothers and health-care staff. Interventions: Pulse oximetry was performed prior to discharge from hospital and the results of this index test were compared with a composite reference standard (echocardiography, clinical follow-up and follow-up through interrogation of clinical databases). Main outcome measures: Detection of major CHDs – defined as causing death or requiring invasive intervention up to 12 months of age (subdivided into critical CHDs causing death or intervention before 28 days, and serious CHDs causing death or intervention between 1 and 12 months of age); acceptability of testing to parents and staff; and the cost-effectiveness in terms of cost per timely diagnosis. Results: Fifty-three of the 20,055 babies screened had a major CHD (24 critical and 29 serious), a prevalence of 2.6 per 1000 live births. Pulse oximetry had a sensitivity of 75.0% [95% confidence interval (CI) 53.3% to 90.2%] for critical cases and 49.1% (95% CI 35.1% to 63.2%) for all major CHDs. When 23 cases were excluded, in which a CHD was already suspected following antenatal ultrasound, pulse oximetry had a sensitivity of 58.3% (95% CI 27.7% to 84.8%) for critical cases (12 babies) and 28.6% (95% CI 14.6% to 46.3%) for all major CHDs (35 babies). False-positive (FP) results occurred in 1 in 119 babies (0.84%) without major CHDs (specificity 99.2%, 95% CI 99.0% to 99.3%). However, of the 169 FPs, there were six cases of significant but not major CHDs and 40 cases of respiratory or infective illness requiring medical intervention. The prevalence of major CHDs in babies with normal pulse oximetry was 1.4 (95% CI 0.9 to 2.0) per 1000 live births, as 27 babies with major CHDs (6 critical and 21 serious) were missed. Parent and staff participants were predominantly satisfied with screening, perceiving it as an important test to detect ill babies. There was no evidence that mothers given FP results were more anxious after participating than those given true-negative results, although they were less satisfied with the test. White British/Irish mothers were more likely to participate in the study, and were less anxious and more satisfied than those of other ethnicities. The incremental cost-effectiveness ratio of pulse oximetry plus clinical examination compared with examination alone is approximately £24,900 per timely diagnosis in a population in which antenatal screening for CHDs already exists. Conclusions: Pulse oximetry is a simple, safe, feasible test that is acceptable to parents and staff and adds value to existing screening. It is likely to identify cases of critical CHDs that would otherwise go undetected. It is also likely to be cost-effective given current acceptable thresholds. The detection of other pathologies, such as significant CHDs and respiratory and infective illnesses, is an additional advantage. Other pulse oximetry techniques, such as perfusion index, may enhance detection of aortic obstructive lesions.

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Objectives - To explore the views and perspectives of children on the unlicensed/off-label use of medicines in children and on the participation of children in clinical trials. Methods - Focus-group discussions, involving school children, were carried out in a range of primary and secondary schools in Northern Ireland. A purposeful sample was chosen to facilitate representation of various socioeconomic groupings. Results - A total of 123 pupils, aged from 10 to 16 years, from six schools, participated in 16 focus groups. In general, pupils viewed the unlicensed/off-label use of medicines in children as unsafe and unethical and felt it is necessary to test medicines in children to improve the availability of licensed products. The majority felt that older children should be told, and that parents should be told, about the unlicensed/off-label use of medicines in children, yet they recognised some implications of this, such as potential medication non-adherence. Conclusions - This is the first study to explore the views of healthy children on unlicensed medicine use in children. Children were able to recognise potential risks associated with the unlicensed use of medicines and felt it is necessary to test and license more medicines in children. Practice implications - Health care professionals should consider the views of children in decisions that affect their health.

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Background: Age-related macular disease is the leading cause of blind registration in the developed world. One aetiological hypothesis involves oxidation, and the intrinsic vulnerability of the retina to damage via this process. This has prompted interest in the role of antioxidants, particularly the carotenoids lutein and zeaxanthin, in the prevention and treatment of this eye disease. Methods: The aim of this randomised controlled trial is to determine the effect of a nutritional supplement containing lutein, vitamins A, C and E, zinc, and copper on measures of visual function in people with and without age-related macular disease. Outcome measures are distance and near visual acuity, contrast sensitivity, colour vision, macular visual field, glare recovery, and fundus photography. Randomisation is achieved via a random number generator, and masking achieved by third party coding of the active and placebo containers. Data collection will take place at nine and 18 months, and statistical analysis will employ Student's t test. Discussion: A paucity of treatment modalities for age-related macular disease has prompted research into the development of prevention strategies. A positive effect on normals may be indicative of a role of nutritional supplementation in preventing or delaying onset of the condition. An observed benefit in the age-related macular disease group may indicate a potential role of supplementation in prevention of progression, or even a degree reversal of the visual effects caused by this condition.

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Purpose: To determine the effect of coloured light filter overlays on reading rates for people with age-related macular degeneration (AMD). Method: Using a prospective clinical trial design, we examined the null hypothesis that coloured light filter overlays do not improve reading rates in AMD when compared to a clear filter. Reading rates for 12 subjects with non-exudative AMD, associated with a relative scotoma and central fixation (mean age 81 years, SD 5.07 years) were determined using the Rate of Reading Test® (printed, nonsense, lower case sans serif, stationary text) with 10 different, coloured light filter overlays (Intuitive Overlays®; figures in brackets are percentage transmission values); rose (78%), pink (78%), purple (67%), aqua (81%), blue (74%), lime-green (86%), mint-green (85%), yellow (93%), orange (83%) and grey (71%). A clear overlay (Roscolene # 00) (360 cdm-2) with 100% transmittance was used as a control. Results: ANOVA indicated that there was no statistically significant difference in reading rates with the coloured light filter overlays compared to the clear filter. Furthermore, chi-squared analysis indicated that the rose, purple and blue filters had a significantly poorer overall ranking in terms of reading rates compared to the other coloured and clear light filters. Conclusion: Coloured light filter overlays are unlikely to provide a clinically significant improvement in reading rates for people with non-exudative AMD associated with a relative scotoma and central fixation. Copyright © Acta Ophthalmol Scand 2004.

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Background: The Melbourne Edge Test (MET) is a portable forced-choice edge detection contrast sensitivity (CS) test. The original externally illuminated paper test has been superseded by a backlit version. The aim of this study was to establish normative values for age and to assess change with visual impairment. Method: The MET was administered to 168 people with normal vision (18-93 years old) and 93 patients with visual impairment (39-97 years old). Distance visual acuity (VA) was measured with a log MAR chart. Results: In those eyes without disease, MET CS was stable until the age of 50 years (23.8 ± .7 dB) after which it decreased at a rate of ≈1.5 dB per decade. Compared with normative values, people with low vision were found to have significantly reduced CS, which could not be totally accounted for by reduced VA. Conclusions: The MET provides a quick and easy measure of CS, which highlights a reduction in visual function that may not be detectable using VA measurements. © 2004 The College of Optometrists.