158 resultados para Vincent Ferrer


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Purpose To examine the influence of short-term miniscleral contact lens wear on corneal shape, thickness and anterior surface aberrations. Methods Scheimpflug imaging was captured before, immediately following and 3 hours after a short period (3 hours) of miniscleral contact lens wear for 10 young (mean 27 ± 5 years), healthy participants. Natural diurnal variations were considered by measuring baseline diurnal changes obtained on a separate control day without contact lens wear. Results Small but significant anterior corneal flattening was observed immediately following lens removal (overall mean 0.02 ± 0.03 mm, p < 0.001) which returned to baseline levels three hours after lens removal. During the three hour recovery period significant corneal thinning (-13.4 ± 10.5 μm) and posterior surface flattening (0.03 ± 0.02 mm) were also observed (both p < 0.01). The magnitude of posterior corneal flattening during recovery correlated with the amount of corneal thinning (r = 0.69, p = 0.03). Central corneal clearance (maximum tear reservoir depth) was not associated with corneal swelling following lens removal (r = -0.24, p > 0.05). An increase in lower-order corneal astigmatism Z(2,2) was also observed following lens wear (mean -0.144 ± 0.075 μm, p = 0.02). Conclusions Flattening of the anterior corneal surface was observed immediately following lens wear, while ‘rebound’ thinning and flattening of the posterior surface was evident following the recovery period. Modern miniscleral contact lenses that vault the cornea may slightly influence corneal shape and power but do not induce clinically significant corneal oedema during short-term wear.

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This project has extended the knowledge in the hydrothermal synthesis of copper zinc tin sulphide (CZTS) semiconductor material which is regarded as one of the most promising light absorbing material for PV technologies. The investigation of various reaction parameters on the controlled synthesis of CZTS compound has provided important insight into the formation mechanism as well as the crystal growth behaviour of the material. CZTS nanocrystals with different crystal structure and particle size were synthesised throughout this project. The growth mechanism of CZTS crystals through a high temperature annealing treatment was also explored.

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Purpose: To investigate the impact of simulated hyperopia and sustained near work on children’s ability to perform a range of academic-related tasks. Methods: Fifteen visually normal children (mean age: 10.9 ± 0.8 years; 10 males and 5 females) were recruited. Performance on a range of standardised academic-related outcome measures was assessed with and without 2.50 D of simulated bilateral hyperopia (administered in a randomised order), before and after 20 minutes of sustained near work, at two separate testing sessions. Academic-related measures included a standardised reading test (the Neale Analysis of Reading Ability), visual information processing tests (Coding and Symbol Search subtests from the Wechsler Intelligence Scale for Children) and a reading-related eye movement test (the Developmental Eye Movement test). Results: Simulated bilateral hyperopia and sustained near work each independently impaired reading, visual information processing and reading-related eye movement performance (p<0.001). A significant interaction was also demonstrated between these factors (p<0.001), with the greatest decrement in performance observed when simulated hyperopia was combined with sustained near work. This combination resulted in performance reductions of between 5% and 24% across the range of academic-related measures. A significant moderate correlation was also found between the change in horizontal near heterophoria and the change in several of the academic-related outcome measures, following the addition of simulated hyperopia. Conclusions: A relatively low level of simulated bilateral hyperopia impaired children’s performance on a range of academic–related outcome measures, with sustained near work further exacerbating this effect. Further investigations are required to determine the impact of correcting low levels of hyperopia on academic performance in children.

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Purpose: This study investigated the impact of simulated hyperopic anisometropia and sustained near work on performance of academic-related measures in children. Methods: Participants included 16 children (mean age: 11.1 ± 0.8 years) with minimal refractive error. Academic-related outcome measures included a reading test (Neale Analysis of Reading Ability), visual information processing tests (Coding and Symbol Search subtests from the Wechsler Intelligence Scale for Children) and a reading-related eye movement test (Developmental Eye Movement test). Performance was assessed with and without 0.75 D of imposed monocular hyperopic defocus (administered in a randomised order), before and after 20 minutes of sustained near work. Unilateral hyperopic defocus was systematically assigned to either the dominant or non-dominant sighting eye to evaluate the impact of ocular dominance on any performance decrements. Results: Simulated hyperopic anisometropia and sustained near work both independently reduced performance on all of the outcome measures (p<0.001). A significant interaction was also observed between simulated anisometropia and near work (p<0.05), with the greatest decrement in performance observed during simulated anisometropia in combination with sustained near work. Laterality of the refractive error simulation (ocular dominance) did not significantly influence the outcome measures (p>0.05). A reduction of up to 12% in performance was observed across the range of academic-related measures following sustained near work undertaken during the anisometropic simulation. Conclusion: Simulated hyperopic anisometropia significantly impaired academic–related performance, particularly in combination with sustained near work. The impact of uncorrected habitual anisometropia on academic-related performance in children requires further investigation.

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Purpose: Astigmatism is an important refractive condition in children. However, the functional impact of uncorrected astigmatism in this population is not well established, particularly with regard to academic performance. This study investigated the impact of simulated bilateral astigmatism on academic-related tasks before and after sustained near work in children. Methods: Twenty visually normal children (mean age: 10.8 ± 0.7 years; 6 males and 14 females) completed a range of standardised academic-related tests with and without 1.50 D of simulated bilateral astigmatism (with both academic-related tests and the visual condition administered in a randomised order). The simulated astigmatism was induced using a positive cylindrical lens while maintaining a plano spherical equivalent. Performance was assessed before and after 20 minutes of sustained near work, during two separate testing sessions. Academic-related measures included a standardised reading test (the Neale Analysis of Reading Ability), visual information processing tests (Coding and Symbol Search subtests from the Wechsler Intelligence Scale for Children) and a reading-related eye movement test (the Developmental Eye Movement test). Each participant was systematically assigned either with-the-rule (WTR, axis 180°) or against-the-rule (ATR, axis 90°) simulated astigmatism to evaluate the influence of axis orientation on any decrements in performance. Results: Reading, visual information processing and reading-related eye movement performance were all significantly impaired by both simulated bilateral astigmatism (p<0.001) and sustained near work (p<0.001), however, there was no significant interaction between these factors (p>0.05). Simulated astigmatism led to a reduction of between 5% and 12% in performance across the academic-related outcome measures, but there was no significant effect of the axis (WTR or ATR) of astigmatism (p>0.05). Conclusion: Simulated bilateral astigmatism impaired children’s performance on a range of academic–related outcome measures irrespective of the orientation of the astigmatism. These findings have implications for the clinical management of non-amblyogenic levels of astigmatism in relation to academic performance in children. Correction of low to moderate levels of astigmatism may improve the functional performance of children in the classroom.

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Purpose: To provide a comprehensive overview of research examining the impact of astigmatism on clinical and functional measures of vision, the short and longer term adaptations to astigmatism that occur in the visual system, and the currently available clinical options for the management of patients with astigmatism. Recent findings: The presence of astigmatism can lead to substantial reductions in visual performance in a variety of clinical vision measures and functional visual tasks. Recent evidence demonstrates that astigmatic blur results in short-term adaptations in the visual system that appear to reduce the perceived impact of astigmatism on vision. In the longer term, uncorrected astigmatism in childhood can also significantly impact on visual development, resulting in amblyopia. Astigmatism is also associated with the development of spherical refractive errors. Although the clinical correction of small magnitudes of astigmatism is relatively straightforward, the precise, reliable correction of astigmatism (particularly high astigmatism) can be challenging. A wide variety of refractive corrections are now available for the patient with astigmatism, including spectacle, contact lens and surgical options. Conclusion: Astigmatism is one of the most common refractive errors managed in clinical ophthalmic practice. The significant visual and functional impacts of astigmatism emphasise the importance of its reliable clinical management. With continued improvements in ocular measurement techniques and developments in a range of different refractive correction technologies, the future promises the potential for more precise and comprehensive correction options for astigmatic patients.

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Purpose To examine macular retinal thickness and retinal layer thickness with spectral domain optical coherence tomography (OCT) in a population of children with normal ocular health and minimal refractive errors. Methods High resolution macular OCT scans from 196 children aged from 4 to 12 years (mean age 8 ± 2 years) were analysed to determine total retinal thickness and the thickness of 6 different retinal layers across the central 5 mm of the posterior pole. Automated segmentation with manual correction was used to derive retinal thickness values. Results The mean total retinal thickness in the central 1 mm foveal zone was 255 ± 16 μm, and this increased significantly with age (mean increase of 1.8 microns per year) in childhood (p<0.001). Age-related increases in thickness of some retinal layers were also observed, with changes of highest statistical significance found in the outer retinal layers in the central foveal region (p<0.01). Significant topographical variations in thickness of each of the retinal layers were also observed (p<0.001). Conclusions Small magnitude, statistically significant increases in total retinal thickness and retinal layer thickness occur from early childhood to adolescence. The most prominent changes appear to occur in the outer retinal layers of the central fovea.

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Purpose – The purpose of this paper is to examine empirically, an industry development paradox, using embryonic literature in the area of strategic supply chain management, together with innovation management literature. This study seeks to understand how, forming strategic supply chain relationships, and developing strategic supply chain capability, influences beneficial supply chain outcomes expected from utilizing industry-led innovation, in the form of electronic business solutions using the internet, in the Australian beef industry. Findings should add valuable insights to both academics and practitioners in the fields of supply chain innovation management and strategic supply chain management, and expand knowledge to current literature. Design/methodology/approach – This is a quantitative study comparing innovative and non-innovative supply chain operatives in the Australian beef industry, through factor analysis and structural equation modeling using PAWS Statistical V18 and AMOS V18 to analyze survey data from 412 respondents from the Australian beef supply chain. Findings – Key findings are that both innovative and non-innovative supply chain operators attribute supply chain synchronization as only a minor indicator of strategic supply chain capability, contrary to the literature; and they also indicate strategic supply chain capability has a minor influence in achieving beneficial outcomes from utilizing industry-led innovation. These results suggest a lack of coordination between supply chain operatives in the industry. They also suggest a lack of understanding of the benefits of developing a strategic supply chain management competence, particularly in relation to innovation agendas, and provides valuable insights as to why an industry paradox exists in terms of the level of investment in industry-led innovation, vs the level of corresponding benefit achieved. Research limitations/implications – Results are not generalized due to the single agribusiness industry studied and the single research method employed. However, this provides opportunity for further agribusiness studies in this area and also studies using alternate methods, such as qualitative, in-depth analysis of these factors and their relationships, which may confirm results or produce different results. Further, this study empirically extends existing theoretical contributions and insights into the roles of strategic supply chain management and innovation management in improving supply chain and ultimately industry performance while providing practical insights to supply chain practitioners in this and other similar agribusiness industries. Practical implications – These findings confirm results from a 2007 research (Ketchen et al., 2007) which suggests supply chain practice and teachings need to take a strategic direction in the twenty-first century. To date, competence in supply chain management has built up from functional and process orientations rather than from a strategic perspective. This study confirms that there is a need for more generalists that can integrate with various disciplines, particularly those who can understand and implement strategic supply chain management. Social implications – Possible social implications accrue through the development of responsible government policy in terms of industry supply chains. Strategic supply chain management and supply chain innovation management have impacts to the social fabric of nations through the sustainability of their industries, especially agribusiness industries which deal with food safety and security. If supply chains are now the competitive weapon of nations then funding innovation and managing their supply chain competitiveness in global markets requires a strategic approach from everyone, not just the industry participants. Originality/value – This is original empirical research, seeking to add value to embryonic and important developing literature concerned with adopting a strategic approach to supply chain management. It also seeks to add to existing literature in the area of innovation management, particularly through greater understanding of the implications of nations developing industry-wide, industry-led innovation agendas, and their ramifications to industry supply chains.

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New public management (NPFM), with its hands-on, private sector-style performance measurement, output control, parsimonious use of resources, disaggreation of public sector units and greater competition in the public sector, has significantly affected charitable and nonprofit organisations delivering community services (Hood, 1991; Dunleavy, 1994; George & Wilding, 2002). The literature indicates that nonprofit organisations under NPM believe they are doing more for less: while administration is increasing, core costs are not being met; their dependence on government funding comes at the expense of other funding strategies; and there are concerns about proportionality and power asymmetries in the relationship (Kerr & Savelsberg, 2001; Powell & Dalton, 2011; Smith, 2002, p. 175; Morris, 1999, 2000a). Government agencies are under increased pressure to do more with less, demonstrate value for money, measure social outcomes, not merely outputs and minimise political risk (Grant, 2008; McGreogor-Lowndes, 2008). Government-community service organisation relationships are often viewed as 'uneasy alliances' characterised by the pressures that come with the parties' differing roles and expectations and the pressures that come with the parties' differing roles and expectations and the pressurs of funding and security (Productivity Commission, 2010, p. 308; McGregor-Lowndes, 2008, p. 45; Morris, 200a). Significant community services are now delivered to citizens through such relationships, often to the most disadvantaged in the community, and it is important for this to be achieved with equity, efficiently and effectively. On one level, the welfare state was seen as a 'risk management system' for the poor, with the state mitigating the risks of sickness, job loss and old age (Giddens, 1999) with the subsequent neoliberalist outlook shifting this risk back to households (Hacker, 2006). At the core of this risk shift are written contracts. Vincent-Jones (1999,2006) has mapped how NPM is characterised by the use of written contracts for all manner of relations; e.g., relgulation of dealings between government agencies, between individual citizens and the state, and the creation of quais-markets of service providers and infrastructure partners. We take this lens of contracts to examine where risk falls in relation to the outsourcing of community services. First we examine the concept of risk. We consider how risk might be managed and apportioned between governments and community serivce organisations (CSOs) in grant agreements, which are quasiy-market transactions at best. This is informed by insights from the law and economics literature. Then, standard grant agreements covering several years in two jurisdictions - Australia and the United Kingdom - are analysed, to establish the risk allocation between government and CSOs. This is placed in the context of the reform agenda in both jurisdictions. In Australia this context is th enonprofit reforms built around the creation of a national charities regulator, and red tape reduction. In the United Kingdom, the backdrop is the THird Way agenda with its compacts, succeed by Big Society in a climate of austerity. These 'case studies' inform a discussion about who is best placed to bear and manage the risks of community service provision on behalf of government. We conclude by identifying the lessons to be learned from our analysis and possible pathways for further scholarship.

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Echolocation calls of 119 bats belonging to 12 species in three families from Antillean islands of Puerto Rico, Dominica, and St. Vincent were recorded by using time-expansion methods. Spectrograms of calls and descriptive statistics of five temporal and frequency variables measured from calls are presented. The echolocation calls of many of these species, particularly those in the family Phyllostomidae, have not been described previously. The wing morphology of each taxon is described and related to the structure of its echolocation calls and its foraging ecology. Of slow aerial-hawking insectivores, the Mormoopidae and Natalidae Mormoops blainvillii, Pteronotus davyi davyi, P. quadridens fuliginosus, and Natalus stramineus stramineus can forage with great manoeuvrability in background-cluttered space (close to vegetation), and are able to hover. Pteronotus parnellii portoricensis is able to fly and echolocate in highly-cluttered space (dense vegetation). Among frugivores, nectarivores and omnivores in the family Phyllostomidae, Brachyphylla cavernarum intermedia is adapted to foraging in the edges of vegetation in background-cluttered space, while Erophylla bombifrons bombifrons, Glossophaga longirostris rostrata, Artibeus jamaicensis jamaicensis, A. jamaicensis schwartzi and Stenoderma rufum darioi are adapted to foraging under canopies in highly-cluttered space and do not have speed or efficiency in commuting flight. In contrast, Monophyllus plethodon luciae, Sturnira lilium angeli and S. lilium paulsoni are adapted to fly in highly-cluttered space, but can also fly fast and efficiently in open areas.

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Purpose Dermatologic adverse events (dAEs) in cancer treatment are frequent with the use of targeted therapies. These dAEs have been shown to have significant impact on health-related quality of life (HRQoL). While standardized assessment tools have been developed for physicians to assess severity of dAEs, there is a discord between objective and subjective measures. The identification of patient-reported outcome (PRO) instruments useful in the context of targeted cancer therapies is therefore important in both the clinical and research settings for the overall evaluation of dAEs and their impact on HRQoL. Methods A comprehensive, systematic literature search of published articles was conducted by two independent reviewers in order to identify PRO instruments previously utilized in patient populations with dAEs from targeted cancer therapies. The identified PRO instruments were studied to determine which HRQoL issues relevant to dAEs were addressed, as well as the process of development and validation of these instruments. Results Thirteen articles identifying six PRO instruments met the inclusion criteria. Four instruments were general dermatology (Skindex-16©, Skindex-29©, Dermatology Life Quality Index (DLQI), and DIELH-24) and two were symptom-specific (functional assessment of cancer therapy-epidermal growth factor receptor inhibitor-18 (FACT-EGFRI-18) and hand-foot syndrome-14 (HFS-14)). Conclusions While there are several PRO instruments that have been tested in the context of targeted cancer therapy, additional work is needed to develop new instruments and to further validate the instruments identified in this study in patients receiving targeted therapies.

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A new imaging methodology is described to visualise the post lens tear film (PLTF) during contact lens wear. A rotating-Scheimpflug camera in combination with sodium fluorescein allows evaluation of the PLTF for different contact lens modalities, including mini-scleral, rigid gas permeable (RGP) and soft contact lenses. This imaging technique provides an extension of the instrument’s current functionality. The potential advantages and limitations of the technique are discussed.

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The concept of ‘power’ can refer to the institutionalised and embodied capacity and right to dominate through a variety of means including ideology, politics, science, religion, class, race, gender and sexuality. Early feminist theorising within the West, for example, conceptualised the structure and nature of power as being connected to male domination and authority within society. Marxists, alternately, argue it is the ruling class that holds power and exercises it as owners of the means of production. In a general sense, we can say that as feminists have tied power to patriarchy and Marxists’ definitions of power have been connected to capitalism. The essays in this section, though, are less concerned with such totalising conceptualisations of power than they are with processes of interpellation or subject creation within dominant or dominating discursive spaces.1 Not power as such, but its many workings and apparatuses.